阅读说明：本技术 标签 (Label (R) ) 是由 I·措米克 F·科甘 L·布劳恩 D·斯克维尔斯基 于 2019-07-24 设计创作，主要内容包括：在本文中描述了一种提供印刷标签的方法。所述方法包括将可辐射固化罩面漆组合物施加到布置在标签基底上的液体静电印刷的墨水上；其中所述可辐射固化罩面漆组合物包含可辐射固化单体和/或低聚物；光引发剂；含有至少两个反应性官能团的聚烷基硅氧烷,其中所述反应性官能团选自氢、羟基、氨基和双键；和含有至少两个环氧基的交联剂。在本文中也描述了印刷标签和可辐射固化罩面漆组合物。(A method of providing a printed label is described herein. The method comprises applying a radiation curable finish composition to a liquid electrostatically printed ink disposed on a label substrate; wherein the radiation curable finish composition comprises radiation curable monomers and/or oligomers; a photoinitiator; a polyalkylsiloxane containing at least two reactive functional groups, wherein the reactive functional groups are selected from the group consisting of hydrogen, hydroxyl, amino, and double bonds; and a crosslinking agent containing at least two epoxy groups. Printed labels and radiation curable finish compositions are also described herein.)

1. A method of providing a printed label, the method comprising:

applying a radiation curable finish composition to a liquid electrostatically printed ink disposed on the label substrate; wherein the radiation curable finish composition comprises:

radiation curable monomers and/or oligomers;

a photoinitiator;

a polyalkylsiloxane containing at least two reactive functional groups, wherein the reactive functional groups are selected from the group consisting of hydrogen, hydroxyl, amino, and double bonds; and

a crosslinking agent containing at least two epoxy groups.

2. The method according to claim 1, wherein the crosslinker containing at least two epoxy groups is present in an amount of 20 wt.% or less of the solids of the radiation curable finish composition.

3. The method according to claim 1, wherein the polyalkylsiloxane containing at least two reactive functional groups is present in an amount of 20 wt.% or less of the solids of the radiation curable finish composition.

4. The method according to claim 1, wherein the polyalkylsiloxane containing at least two reactive functional groups has the formula:

wherein

Each R is independently selected from C1 to C6 alkyl;

each X ', X ", and X'" is independently selected from C1 to C6 alkyl, hydrogen, hydroxy, amino, C2 to C6 alkenyl, C1 to C6 carboxylic acid, C2 to C6 ester, and mixtures thereof;

sis 0 or greater; and

tis 1 or greater;

wherein

If s is 0:

x' and X ″ are each independently selected from hydrogen, hydroxy, amino, C2 to C6 alkenyl, C1 to C6 carboxylic acid, C1 to C6 ester, and mixtures thereof; and

if it is notsIs 1:

at least one of X' and X "is selected from hydrogen, hydroxy, amino, C2 to C6 alkenyl, C1 to C6 carboxylic acid, C1 to C6 ester, and mixtures thereof.

5. The process according to claim 1, wherein the crosslinking agent containing at least two epoxy groups is a diglycidyl ether.

6. The process of claim 1 wherein the crosslinking agent containing at least two epoxy groups is formed by the reaction of an epihalohydrin with a diol.

7. The process according to claim 6, wherein the diol is an alkyl diol.

8. The method according to claim 1, wherein the crosslinking agent is selected from the group consisting of methylene glycol diglycidyl ether, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, butanediol diglycidyl ether, pentanediol diglycidyl ether, hexanediol diglycidyl ether, heptanediol diglycidyl ether, and octanediol diglycidyl ether, neopentyl glycol diglycidyl ether, cyclohexanedimethanol diglycidyl ether, resorcinol diglycidyl ether, trimethylolethane triglycidyl ether, trimethylolpropane triglycidyl ether, propoxylated diol triglycidyl ether, pentaerythritol polyglycidyl ether, and sorbitol polyglycidyl ether.

9. The method according to claim 1, wherein the radiation curable monomers and/or oligomers are selected from the group consisting of molecules comprising multiple epoxy groups, molecules comprising multiple olefin groups, molecules comprising multiple acrylate groups, and combinations thereof.

10. The method according to claim 1, wherein the crosslinking agent contains two epoxy groups.

11. The method according to claim 1, wherein the polyalkylsiloxane contains two reactive functional groups.

12. The method of claim 1, wherein the polyalkylsiloxane containing at least two functional groups comprises a polyalkylsiloxane having the formula I:

formula I

Wherein:

each R is independently selected from C1 to C6 alkyl;

each X is independently selected from hydrogen, hydroxy, amino, C2 to C6 alkenyl, C1 to C6 carboxylic acid, C2 to C6 ester, C1 to C6 imine, and mixtures thereof; and

pis 1 or greater.

13. The method of claim 1, wherein a primer is disposed between the liquid electrostatically printed ink and the label substrate.

14. A printed label, comprising:

a label substrate;

a liquid electrostatically printed ink disposed on the label substrate; and

a finish composition disposed on the liquid electrostatically printed ink that has been cured under irradiation;

wherein the finish composition comprises a radiation cured product of a radiation curable finish composition comprising:

radiation curable monomers and/or oligomers;

a photoinitiator;

a polyalkylsiloxane containing at least two reactive functional groups, wherein the reactive functional groups are selected from the group consisting of hydrogen, hydroxyl, amino, and double bonds; and

a crosslinking agent containing at least two epoxy groups.

15. A radiation curable finish composition comprising:

radiation curable monomers and/or oligomers;

a photoinitiator;

a polyalkylsiloxane containing at least two reactive functional groups, wherein the reactive functional groups are selected from the group consisting of hydrogen, hydroxyl, amino, and double bonds; and

a crosslinking agent containing at least two epoxy groups.

Background

Printed labels are used on or in many types of products to display information, differentiate products, and comply with regulatory requirements, such as ingredient lists, safety warnings, and the like.

Brief Description of Drawings

Figure 1 schematically shows an example of a method of providing a printed label.

Figure 2 schematically shows another example of a method of providing a printed label.

Fig. 3 schematically shows a further example of a method of providing a printed label.

Fig. 4 shows the results of the mechanical resistance test.

Fig. 5 shows the results of the wet scratch resistance test.

Detailed description of the invention

Before the present disclosure is disclosed and described, it is to be understood that this disclosure is not limited to the particular process features and materials disclosed herein as such process features and materials may vary. It is also to be understood that the terminology used herein is used for the purpose of describing particular examples.

It is noted that, as used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise.

As used herein, "carrier fluid", "carrier liquid" or "carrier vehicle" in the context of an electrostatic ink composition refers to a fluid in which pigment particles, colorants, charge directors, and other additives may be dispersed to form a liquid electrostatic or electrophotographic composition. The carrier liquid may contain a mixture of various different agents, such as surfactants, co-solvents, viscosity modifiers, and/or other possible ingredients.

As used herein, an "electrostatic ink composition", "liquid electrophotographic composition", or "liquid electrostatic ink composition" generally refers to an ink composition that is generally suitable for use in an electrostatic printing process (sometimes referred to as an electrophotographic printing process). It may comprise pigment particles, which may comprise a thermoplastic resin.

As used herein, "pigment" generally includes pigment colorants, magnetic particles, alumina, silica, and/or other ceramic or organometallic, whether or not such particulates impart color. Thus, although the present specification primarily exemplifies the use of pigment colorants, the term "pigment" may be used more generally to describe not only pigment colorants, but also other pigments, such as organometallics, ferrites, ceramics, and the like.

As used herein, "copolymer" refers to a polymer polymerized from at least two monomers.

As used herein, "melt flow rate" generally refers to the extrusion rate at which a resin is extruded through an orifice of a specified size at a specified temperature and load (typically reported as temperature/load, e.g., 190 ℃/2.16 kg). The flow rate can be used to grade or provide a measure of material degradation caused by molding. In the present disclosure, "Melt Flow rate" is measured according to ASTM D1238-04c Standard Test Method for Melt Flow Rates of Thermoplastics by Extrusion Plastometer. If the melt flow rate of a particular polymer is specified, it is the melt flow rate of the polymer itself in the absence of any other component of the electrostatic composition, unless otherwise specified.

As used herein, "acidity", "acid number" or "acid value" refers to the mass of potassium hydroxide (KOH) in milligrams that neutralizes 1 gram of material. The acidity of the polymer can be measured according to standard techniques such as those described in ASTM D1386. If the acidity of a particular polymer is specified, it is the acidity of the polymer itself in the absence of any other component of the liquid toner composition, unless otherwise specified.

As used herein, "melt viscosity" generally refers to the ratio of shear stress to shear rate at a given shear stress or shear rate. Testing is typically performed using a capillary rheometer. The plastic charge was heated in the rheometer barrel and pushed through the die with a plunger. Depending on the equipment, the plunger is pushed with a constant force or at a constant rate. Once the system reaches steady state operation, measurements are taken. One method used is to measure the Brookfield viscosity at 140 ℃ in mPa ∙ s or cPoise. In some examples, melt viscosity can be measured using a rheometer, such as a commercially available AR-2000 rheometer from Thermal Analysis Instruments, using a 25 mm steel plate-standard steel parallel plate geometry and deriving a plate-to-plate (plate over plate) rheological isotherm at 120 ℃ at a shear rate of 0.01 hz. If the melt viscosity of a particular polymer is specified, it is the melt viscosity of the polymer itself in the absence of any other component of the electrostatic ink composition, unless otherwise specified.

A certain monomer may be described herein as a particular weight percentage of the constituent polymer. This means that the repeating units formed from the monomers in the polymer constitute said weight percentage of the polymer.

If reference is made herein to a standard test, unless otherwise indicated, the test version to be referred to is the most recent version at the time of filing the present patent application.

As used herein, "electrostatic printing" or "electrophotographic printing" generally refers to a process that provides an image that is transferred from a photoimageable substrate to a substrate, such as a label substrate, either directly or indirectly via an intermediate transfer member. Thus, the image is not substantially absorbed into the photoimageable substrate to which it is applied. In addition, "electrophotographic printer" or "electrostatic printer" generally refers to a printer capable of performing electrophotographic printing or electrostatic printing as described above. "liquid electrophotographic printing" is a particular type of electrophotographic printing in which a liquid composition is used in the electrophotographic process rather than a toner. The electrostatic printing method may involve applying an electric field to the electrostatic composition, for example, an electric field having a field gradient of 50-400V/μm or greater, in some examples 600-900V/μm or greater.

As used herein, "substituted" may mean that a hydrogen atom of a compound or group is replaced with another atom, such as a carbon atom or a heteroatom, that is part of the group referred to as a substituent. Substituents include, for example, alkyl, alkoxy, aryl, aryloxy, alkenyl, alkenyloxy, alkynyl, alkynyloxy, sulfanyl, thioalkenyl, thioalkynyl, thioaryl, and the like.

As used herein, "heteroatom" may refer to nitrogen, oxygen, halogen, phosphorus or sulfur.

As used herein, "alkyl" or a similar expression, such as "alkane" in an alkoxy group, may refer to a branched, straight chain or cyclic saturated hydrocarbon group that may contain, in some instances, from 1 to about 50 carbon atoms, or from 1 to about 40 carbon atoms, or from 1 to about 30 carbon atoms, or from 1 to about 10 carbon atoms, or from 1 to about 5 carbon atoms.

The term "alkenyl" may refer to a branched, straight-chain, or cyclic unsaturated hydrocarbon group that may or may not be conjugated and in some instances is not aromatic, that may contain one or more double bonds, one or more triple bonds, or any combination thereof. Alkenyl groups described herein can contain, but are not limited to, 2 to about 50 carbon atoms, or 2 to about 40 carbon atoms, or 2 to about 30 carbon atoms, or 2 to about 20 carbon atoms, or 2 to about 10 carbon atoms, or 2 to about 5 carbon atoms.

The term "aryl" may refer to a group containing a single aromatic ring or multiple aromatic rings fused together, directly linked, or indirectly linked (such that the different aromatic rings are bonded to a common group such as a methylene or ethylene group). The aryl groups described herein may contain, but are not limited to, 5 to about 50 carbon atoms, or 5 to about 40 carbon atoms, or 5 to about 30 carbon atoms or more, and may be selected from phenyl and naphthyl.

The term "about" is used herein to provide flexibility to the end points of a numerical range, where a given value may be slightly above or below the end point to account for variations in the test method or apparatus. As understood in the art, the degree of flexibility of this term may depend on the particular variable.

As used herein, a plurality of items, structural elements, compositional elements, and/or materials may be presented in a general list for convenience. However, these lists should be construed as if each member of the list is individually identified as a separate and unique member. Thus, any member of such a list should not be construed as a de facto equivalent of any other member of the same list solely based on their presence in the same group if not otherwise indicated.

Concentrations, amounts, and other numerical data may be expressed or presented herein in a range format. It is to be understood that such a range format is used merely for convenience and brevity and thus should be interpreted flexibly to include not only the numerical values explicitly recited as the limits of the range, but also to include all the individual numerical values or sub-ranges encompassed within that range as if each numerical value and sub-range is explicitly recited. For example, a numerical range of "about 1 wt% to about 5 wt%" should be interpreted to include not only the explicitly recited values of about 1 wt% to about 5 wt%, but also include individual values and sub-ranges within the indicated range. Accordingly, included in this numerical range are individual values, e.g., 2, 3.5, and 4, and sub-ranges, e.g., 1-3, 2-4, and 3-5, etc. This principle applies equally to ranges reciting a single numerical value. Moreover, such an interpretation applies regardless of the breadth of the range or the characteristics being described.

As used herein, in the case of an electrostatic ink composition, unless the context indicates otherwise, a wt% value should be considered to refer to the weight-weight (w/w) percentage of solids in the ink composition, and not to include the weight of any carrier fluid present.

Any feature described herein may be combined with any aspect or any other feature described herein, unless otherwise specified.

In one aspect, a method of providing a printed label is provided. The method may comprise:

applying a radiation curable finish (overprat) composition to a liquid electrostatically printed ink disposed on a label substrate; wherein the radiation curable finish composition comprises:

radiation curable monomers and/or oligomers;

a photoinitiator;

a polyalkylsiloxane containing at least two reactive functional groups, wherein the reactive functional groups are selected from the group consisting of hydrogen, hydroxyl, amino, and double bonds; and

a crosslinking agent containing at least two epoxy groups.

In another aspect, a printed label is provided. The printed label may include:

a label substrate;

a liquid electrostatically printed ink disposed on the label substrate; and

a finish composition disposed on the liquid electrostatically printed ink that has been cured under irradiation;

wherein the finish composition comprises a radiation cured product of a radiation curable finish composition comprising:

radiation curable monomers and/or oligomers;

a photoinitiator;

a polyalkylsiloxane containing at least two reactive functional groups, wherein the reactive functional groups are selected from the group consisting of hydrogen, hydroxyl, amino, and double bonds; and

a crosslinking agent containing at least two epoxy groups.

In yet another aspect, a radiation curable finish composition is provided comprising:

radiation curable monomers and/or oligomers;

a photoinitiator;

a polyalkylsiloxane containing at least two reactive functional groups, wherein the reactive functional groups are selected from the group consisting of hydrogen, hydroxyl, amino, and double bonds; and

a crosslinking agent containing at least two epoxy groups.

An ink and finish set is also provided. The ink and finish set may comprise:

a liquid electrostatic printing ink composition; and

a radiation curable finish composition comprising:

radiation curable monomers and/or oligomers;

a photoinitiator;

a polyalkylsiloxane containing at least two reactive functional groups, wherein the reactive functional groups are selected from the group consisting of hydrogen, hydroxyl, amino, and double bonds; and

a crosslinking agent containing at least two epoxy groups.

Labels, such as pressure sensitive labels, are used on a variety of products, many of which are stored under humid conditions and/or are used to store aqueous compositions (e.g., shampoo bottles and wine bottles). It is therefore desirable that the printed labels resist mechanical action and damage from water and chemicals so that the information printed thereon remains visible under conditions of storage, transport, display and use of the printed labels. The present inventors have found that many labels printed with xerographic inks are susceptible to damage by water and mechanical action during their lifetime. It has been found that the examples of the methods and products described herein avoid or at least mitigate at least one of these difficulties. It has been found that examples of these methods and products have increased durability in aqueous environments and under mechanical action to provide increased wet scratch and rub resistance to printed labels.

Printed label

In some examples, printed labels are described. The printed label may be produced by any of the methods described herein. The components of the printed label are discussed in the following sections.

In some examples, the printed label includes a label substrate; a liquid electrostatically printed ink disposed on the label substrate; and a finish composition disposed on the liquid electrostatically printed ink that has been cured under irradiation. In some examples, the printed label includes a label substrate; a liquid electrostatically printed ink disposed on the label substrate; and a finish composition disposed on the liquid electrostatically printed ink that has been cured under irradiation; wherein the finish composition comprises a radiation cured product of a radiation curable finish composition comprising: radiation curable monomers and/or oligomers; a photoinitiator; a polyalkylsiloxane containing at least two reactive functional groups, wherein the reactive functional groups are selected from the group consisting of hydrogen, hydroxyl, amino, and double bonds; and a crosslinking agent containing at least two epoxy groups.

In some examples, the printed label includes a label substrate; a primer disposed on the label substrate; a liquid electrostatically printed ink disposed on the primer; and a finish composition disposed on the liquid electrostatically printed ink that has been cured under irradiation. In some examples, the printed label includes a label substrate; a primer disposed on the label substrate; a liquid electrostatically printed ink disposed on the primer; and a finish composition disposed on the liquid electrostatically printed ink that has been cured under irradiation; wherein the finish composition comprises a radiation cured product of a radiation curable finish composition comprising: radiation curable monomers and/or oligomers; a photoinitiator; a polyalkylsiloxane containing at least two reactive functional groups, wherein the reactive functional groups are selected from the group consisting of hydrogen, hydroxyl, amino, and double bonds; and a crosslinking agent containing at least two epoxy groups.

Radiation curable finish composition

The radiation curable overcoat composition can be applied to a liquid xerographic ink. In some examples, a printed label may include a printed label substrate and a finish composition disposed on a printed ink that has been cured under irradiation. In some examples, a printed label may include a label substrate; an electrostatically printed ink disposed on the label substrate and a finish composition disposed on the printed ink that has been cured under irradiation. In some examples, a printed label may include a label substrate; a primer disposed on the label substrate; an electrostatically printed ink disposed on the primer and a finish composition disposed on the printed ink that has been cured under irradiation.

The radiation curable finish composition may comprise (i) a component selected from the group consisting of radiation curable monomers and radiation curable oligomers or mixtures thereof; (ii) a photoinitiator; (iii) a polyalkylsiloxane containing at least two reactive functional groups; and (iv) a crosslinking agent containing at least two epoxy groups. The radiation curable finish composition may comprise (i) a component selected from the group consisting of radiation curable monomers and radiation curable oligomers or mixtures thereof; (ii) a photoinitiator; (iii) a polyalkylsiloxane containing at least two reactive functional groups, wherein the reactive functional groups are selected from the group consisting of hydrogen, hydroxyl, amino, and double bonds; and (iv) a crosslinking agent containing at least two epoxy groups.

In some examples, the radiation curable finish composition may comprise (i) a component selected from the group consisting of radiation curable monomers and radiation curable oligomers, or mixtures thereof; (ii) a photoinitiator; (iii) a polyalkylsiloxane containing at least two reactive functional groups; and (iv) a crosslinker containing at least two epoxy groups and a finish composition solvent. In some examples, the finish composition solvent can be a carrier liquid as described below. The finish composition solvent may be a solvent selected from the group consisting of water, alcohols, e.g., C1 to C3 alkanols (e.g., methanol or ethanol), esters, and glycol ethers.

In some examples, the radiation curable finish composition can be substantially free of solvent. By substantially solvent-free, it can be meant that the radiation curable finish composition contains 5 wt.% or less solvent, such as 2 wt.% or less, 1 wt.% or less, or 0.5 wt.% or less solvent. In some examples, the radiation curable finish composition is solvent free.

As used herein, an oligomer is a short polymer that may contain no more than 100 monomers. In some examples, the oligomer is a polymer having a chain length of 100 monomers or less, such as 50 monomers or less, such as 40 monomers or less, such as 30 monomers or less, such as 20 monomers or less, such as 15 monomers or less, or such as 10 monomers or less.

In some examples, the radiation curable finish composition is a photocurable finish composition (e.g., a cocoa-light curable composition or a uv-curable finish composition), a thermally curable finish composition, an electron beam curable finish composition, an ionizing radiation curable finish composition (e.g., a gamma radiation curable finish composition), a non-ionizing radiation curable finish composition (e.g., a microwave radiation curable finish composition). In some examples, the photocurable finish composition is an ultraviolet curable finish composition.

In some examples, the radiation-curable monomers are photocurable monomers (e.g., cocoa-visible-light-curable monomers or ultraviolet-curable monomers), thermally-curable monomers, electron-beam-curable monomers, ionizing radiation-curable monomers (e.g., gamma-radiation-curable monomers), non-ionizing radiation-curable monomers (e.g., microwave radiation-curable monomers). In some examples, the photocurable monomer is an ultraviolet curable monomer.

In some examples, the radiation curable oligomer is a photocurable oligomer (e.g., a cocoa-visible curable oligomer or a uv-curable oligomer), a thermally curable oligomer, an electron beam curable oligomer, an ionizable radiation curable oligomer (e.g., a gamma radiation curable oligomer), a non-ionizable radiation curable oligomer (e.g., a microwave radiation curable oligomer). In some examples, the photocurable oligomer is a uv curable oligomer.

In some examples, the radiation curable monomers and/or oligomers are selected from mono-epoxy group-containing molecules and olefin group-containing molecules. In some examples, the radiation curable monomers and/or oligomers are molecules comprising multiple olefinic groups. As used herein, a molecule comprising a plurality of groups of a particular type may comprise 2 or more, in some examples 3 or more, in some examples 4 or more groups of that type.

In some examples, the olefin group-containing molecule can be selected from the group consisting of styrenes, acrylates, methacrylates, allyl-containing compounds, alkenyl carboxylic acids, alkenyl esters, alkenyl amides, dienes, alkenyl cyanides, alkenyl ethers, carbamates, alkenyl alcohols, alkenyl thiols, halogenated alkenes, and combinations thereof. In some examples, the molecule comprising multiple alkene groups may include styrenes, acrylates, methacrylates, allyl-containing compounds, alkenyl carboxylic acids, alkenyl esters, alkenyl amides, dienes, alkenyl cyanides, alkenyl ethers, carbamates, alkenyl alcohols, alkenyl thiols, halogenated alkenes, and combinations thereof. In some examples, the olefin group-containing molecule or multiple olefin group-containing molecules can be acrylates, methacrylates, or urethanes. In some examples, the olefin group-containing molecule or multiple olefin group-containing molecules can be an acrylate.

In some examples, the radiation curable finish composition comprises a radiation curable monomer. In some examples, the radiation curable monomer is selected from monofunctional monomers (such as isobornyl acrylate or hydroxypropyl acrylate), difunctional monomers (such as tripropylene glycol diacrylate or dipropylene glycol diacrylate), and trifunctional monomers (such as trimethylolpropane triacrylate or ethoxylated trimethylolpropane triacrylate). The type of monomer included in the radiation curable finish composition can affect the cure and/or coating properties, such as flexibility, adhesion, and viscosity.

In some examples, the radiation curable finish composition comprises a radiation curable oligomer. In some examples, the radiation curable oligomer is selected from the group consisting of urethane acrylates, urethane methacrylates, polyester acrylates, polyester methacrylates, acrylic methacrylates, and methacrylic acrylates.

In some examples, the radiation curable finish composition comprises an acrylate selected from the group consisting of mono-, di-, tri-, and tetra-acrylates and combinations thereof. In some examples, the radiation curable finish composition comprises an acrylate selected from the group consisting of di-, tri-, and tetra-acrylates and combinations thereof. In some examples, the radiation curable finish composition comprises an acrylate selected from the group consisting of mono-, di-, and tri-acrylates and combinations thereof. In some examples, the radiation curable finish composition comprises an acrylate selected from the group consisting of di-and tri-acrylates and combinations thereof.

In some examples, the radiation curable finish composition comprises a compound selected from the group consisting of ethoxylated trimethylolpropane triacrylate, dipropylene glycol diacrylate, hydroxypropyl acrylate, polysiloxane acrylate hexamethylene diacrylate, acrylates of ethoxylated pentaerythritol, acrylates of ethoxylated tripropylene glycol, glycerol acrylates, acrylates (propenoic acid esters), and combinations thereof. In some examples, the radiation curable finish composition comprises a compound selected from the group consisting of ethoxylated trimethylolpropane triacrylate, dipropylene glycol diacrylate, hydroxypropyl acrylate, polysiloxane acrylate hexamethylene diacrylate, and combinations thereof. In some examples, the radiation curable finish composition comprises ethoxylated trimethylolpropane triacrylate, dipropylene glycol diacrylate, hydroxypropyl acrylate, and polysiloxane acrylate hexamethylene diacrylate.

Polyalkylsiloxane

In some examples, the radiation curable finish composition comprises a polyalkylsiloxane. In some examples, the polyalkylsiloxane includes a polyalkylsiloxane containing at least two reactive functional groups. In some examples, the reactive functional group may be reactive with the radiation curable monomer and/or oligomer, the crosslinker, or both. In some examples, the reactive functional group can be reactive to a liquid electrostatically printed ink disposed on the label substrate. In some examples, the reactive functional group may be reactive with a primer disposed between the liquid electrostatically printed ink and the label substrate. In some examples, the reactive functional group may be reactive with a primer disposed between the liquid electrostatically printed ink and the label substrate.

In some examples, the reactive functional group can be reactive with a carboxyl functional group, an amine functional group (e.g., an imine functional group), a polyol functional group, or a combination thereof. In some examples, the reactive functional group can be reactive with a carboxyl functional group and/or an amine functional group. In some examples, the reactive functional group can be reactive with the carboxyl functional group.

In some examples, the polyalkylsiloxane comprises at least two reactive functional groups selected from hydrogen, hydroxyl, amino, and double bonds. In some examples, the double bond may be a carbon-carbon double bond (e.g., an alkene), a carbon-oxygen double bond (e.g., a carboxylic acid, an ester, a carbon-nitrogen double bond (e.g., an imine or an oxime), or a combination thereof (e.g., an acrylic acid, a methacrylic acid, an acrylate, a methacrylate, or an isocyanate).

The polyalkylsiloxane may comprise at least two reactive functional groups. In some examples, the polyalkylsiloxane comprises 2 to 10 reactive functional groups, e.g., 2 to 5, 2 to 4, 2 to 3 reactive functional groups. In some examples, the polyalkylsiloxane may include 2 reactive functional groups.

In some examples, the polyalkylsiloxane containing at least two reactive functional groups is selected from the group consisting of a linear polyalkylsiloxane containing at least two reactive functional groups, a branched polyalkylsiloxane containing at least two reactive functional groups, a cyclic polyalkylsiloxane containing at least two reactive functional groups, and mixtures thereof. In some examples, the polyalkylsiloxane is a linear polyalkylsiloxane containing at least two reactive functional groups.

In some examples, the at least two reactive functional groups may be terminal reactive functional groups, pendant reactive functional groups, or a combination thereof. In some examples, the polyalkylsiloxane may include terminal reactive functional groups.

In some examples, the polyalkylsiloxane containing at least two functional groups includes a polyalkylsiloxane having the formula I, II or III:

formula I

Formula II

Formula III

Wherein:

each R is independently selected from C1 to C6 alkyl;

each X is independently selected from hydrogen, hydroxy, amino, C2 to C6 alkenyl, C1 to C6 carboxylic acid, C2 to C6 ester, C1 to C6 imine, and mixtures thereof;

pis 1 or greater;

qis 2 or greater; and

ris 1 or greater.

In some examples, each R is independently selected from C1, C2, C3, C4, C5, and C6 alkyl. In some examples, each R is independently selected from methyl, ethyl, propyl, isopropyl, isobutyl, and substituted aryl,N-propyl radicalAn isopropyl group,Is justButyl, isobutyl, or isobutyl,Sec-butylIsobutyl, and,Tert-butyl radicalPentyl, 2-methylbut-2-yl, 2-dimethylpropyl, 3-methylbutyl, pent-2-yl and pent-3-yl. In some examples, each R is independently selected from methyl, ethyl, propyl, isopropyl, isobutyl, and substituted aryl,N-propyl radicalAn isopropyl group,Is justButyl, isobutyl, or isobutyl,Sec-butylIsobutyl andtert-butyl radical. In some examples, each R is independently selected from methyl, ethyl, propyl, isopropyl, isobutyl, and substituted aryl,N-propyl radicalAnd an isopropyl group. In some examples, each R is the same. In some examples, each R is methyl.

In some examples, each X is independently selected from hydrogen, hydroxy, amino, C2 to C6 alkenyl, C1 to C6 carboxylic acid, C2 to C6 ester, C1 to C6 imine, and mixtures thereof. In some examples, each X is independently selected from hydrogen, hydroxy, amino, C2 to C6 alkenyl, C1 to C6 carboxylic acid, C2 to C6 ester, and mixtures thereof. In some examples, each X is independently selected from hydrogen, hydroxy, amino, vinyl, C3 to C6 alkenyl, C1 to C6 carboxylic acid, C3 to C6 acrylate, C4 to C6 methacrylate, C2 to C6 ester, C1 to C6 imine, C1 to C6 oxime, and mixtures thereof. In some examples, each X is independently selected from hydrogen, hydroxy, amino, vinyl, C3 to C6 alkenyl, C1 to C6 carboxylic acid, C3 to C6 acrylate, C4 to C6 methacrylate, C2 to C6 ester, and mixtures thereof.

In some examples, C1 to C6 esters can be selected from-O-C (= O) -R ', -C (= O) -O-R ', -R "-O-C (= O) -R '"), and-R "-C (= O) -O-R '", where R ' is selected from C1 to C5 alkyl or C2 to C5 alkenyl; r' is selected from C1 to C4 alkyl or C2 to C4 alkenyl; and R ' ' ' is selected from C1 to C4 alkyl or C2 to C4 alkenyl.

In some examples, each X is independently selected from the group consisting of hydroxyl, vinyl, acrylate, and methacrylate. In some examples, each X is hydroxy.

In some examples, each X is the same.

In some instances, it is desirable to have,qis 2 or greater. In some instances, it is desirable to have,qis 2 to 10, such as 2 to 5, 2 to 4, 2 to 3. In some instances, it is desirable to have,qis 2. In some examples, the X-containing polyalkylsiloxane moieties of the polyalkylsiloxane are randomly arranged within the polyalkylsiloxane chain.

In some instances, it is desirable to have,ris 1 or greater. In some instances, it is desirable to have,ris 1 to 10, such as 1 to 5, 1 to 4, 2 to 3. In some instances, it is desirable to have,ris 1. In some examples, the X-containing polyalkylsiloxane moieties of the polyalkylsiloxane are randomly arranged within the polyalkylsiloxane chain.

In some instances, it is desirable to have,pis 1 or greater. In some instances, it is desirable to have,pis 10,000 or less, such as 5,000 or less, 1,000 or less, 900 or less, 800 or less, 700 or less, 600 or less, 500 or less, 400 or less, 300 or less. In some instances, it is desirable to have,pis 1 or greater, e.g., 2 or greater, 10 or greater, 50 or greater, 100 or greater, 150 or greater, 200 or greater, 250 or greater, 300 or greater, 350 or greater, 400 or greater, 450 or greater, 500 or greater, 550 or greater, 600 or greater, 650 or greater, 700 or greater, 750 or greater, 800 or greater, 850 or greater, 900 or greater, 950 or greater, 1,000 or greater, 5,000 or greater, or 10,000 or greater. In some instances, it is desirable to have,pis 1 to 10,000, e.g., 10 to 5,000, 50 to 1,000, 100 to 900, 150 to 800, 200 to 700, 250 to 700, 300 to 650, 350 to 600, 400 to 1,000, 450 to 850, 500 to 750, 550 to 600.

In some examples, each R is methyl and each X is hydroxy.

In some examples, the polyalkylsiloxane containing at least two functional groups includes a polyalkylsiloxane having formula I:

formula I

Wherein R, X andpas described herein.

In some examples, the polyalkylsiloxane containing at least two functional groups includes a polymethylsiloxane having the formula:

wherein X andpas described herein.

In some examples, the polyalkylsiloxane containing at least two functional groups includes a polymethylsiloxane having the formula:

wherein X andpas described herein.

In some examples, the polyalkylsiloxane containing at least two functional groups includes

Wherein p isAs defined above.

In some examples, the polyalkylsiloxane containing at least two reactive functional groups has the formula:

wherein

Each R is as defined herein;

each X ', X' 'and X' '' is independently selected from R or X, wherein X is as defined herein;

sis 0 or greater; and

tis 1 or greater, or 1 or greater;

wherein

If s is 0:

x ' and X ' ' are each independently X; and

if s isIs 1:

at least one of X ' and X ' ' is X.

In some instances, it is desirable to have,sas herein describedTo pairqOrrAs defined. In some instances, it is desirable to have,tas herein onpAs defined.

In some examples, the polyalkylsiloxane containing at least two reactive functional groups has the formula:

wherein

Each R is independently selected from C1 to C6 alkyl;

each X ', X ", and X'" is independently selected from C1 to C6 alkyl, hydrogen, hydroxy, amino, C2 to C6 alkenyl, C1 to C6 carboxylic acid, C2 to C6 ester, and mixtures thereof;

sis 0 or greater; and

tis 1 or greater, or 1 or greater;

wherein

If s is 0:

x' and X ″ are each independently selected from hydrogen, hydroxy, amino, C2 to C6 alkenyl, C1 to C6 carboxylic acid, C1 to C6 ester, and mixtures thereof; and

if it is notsIs 1:

at least one of X' and X "is selected from hydrogen, hydroxy, amino, C2 to C6 alkenyl, C1 to C6 carboxylic acid, C1 to C6 ester, and mixtures thereof.

In some examples, the polyalkylsiloxane containing at least two reactive functional groups is present in an amount of 20 wt% or less of the solids of the radiation curable finish composition, such as 19 wt% or less, 18 wt% or less, 17 wt% or less, 16 wt% or less, 15 wt% or less, 14 wt% or less, 13 wt% or less, 12 wt% or less, 11 wt% or less, or 10 wt% or less of the solids of the radiation curable finish composition. In some examples, the polyalkylsiloxane containing at least two reactive functional groups is present in an amount of 0.5 wt% or greater of the solids of the radiation curable finish composition, e.g., 1 wt% or greater, 2 wt% or greater, 3 wt% or greater, 4 wt% or greater, 5 wt% or greater, 6 wt% or greater, 7 wt% or greater, 8 wt% or greater, 9 wt% or greater, or 10 wt% or greater of the solids of the radiation curable finish composition. In some examples, the polyalkylsiloxane containing at least two reactive functional groups is present in an amount of 0.5 to 20 weight percent of the total solids of the radiation curable finish composition, such as 1 to 20 weight percent, 2 to 19 weight percent, 3 to 18 weight percent, 4 to 17 weight percent, 5 to 16 weight percent, 6 to 15 weight percent, 7 to 14 weight percent, 8 to 13 weight percent, 9 to 12 weight percent, or 10 to 11 weight percent of the solids of the radiation curable finish composition.

Crosslinking agent

In some examples, the radiation curable finish composition comprises a crosslinker for crosslinking the radiation curable monomers and/or oligomers of the radiation curable finish composition. In some examples, the radiation curable finish composition comprises a crosslinker for crosslinking the thermoplastic resin of the liquid xerographic ink. In some examples, the radiation curable finish composition includes a crosslinker for crosslinking the primer resin of the primer. In some examples, the radiation curable finish composition includes a crosslinker, such as a primer resin for crosslinking the radiation curable monomers and/or oligomers of the radiation curable finish composition, the thermoplastic resin of the liquid electrostatically printed ink, and/or the primer.

In some examples, the radiation curable finish composition includes a crosslinker for crosslinking the radiation curable monomers and/or oligomers of the radiation curable finish composition to the thermoplastic resin of the liquid electrostatically printed ink. In some examples, the radiation curable finish composition includes a crosslinker for crosslinking the radiation curable monomers and/or oligomers of the radiation curable finish composition to the primer resin of the primer. In some examples, the radiation curable finish composition comprises a crosslinker for crosslinking the thermoplastic resin of the liquid electrostatically printed ink to the primer resin of the primer. In some examples, the radiation curable finish composition comprises a thermoplastic resin for crosslinking the radiation curable monomers and/or oligomers of the radiation curable finish composition to the liquid electrostatically printed ink and a crosslinker for crosslinking the thermoplastic resin of the liquid electrostatically printed ink to the primer resin of the primer.

In some examples, the crosslinking agent comprises at least two epoxy groups. In some examples, the crosslinking agent can crosslink any of the following: the radiation curable monomer and/or oligomer in the radiation curable overcoat composition, the thermoplastic resin in the liquid electrostatically printed ink composition, the primer resin in the primer, the monomer and/or oligomer of the radiation curable overcoat composition with the thermoplastic resin in the liquid electrostatically printed ink composition, the monomer and/or oligomer of the radiation curable overcoat composition with the primer resin in the primer, or the thermoplastic resin in the liquid electrostatically printed ink composition with the primer resin in the primer.

In some examples, the crosslinking agent comprises 2 to 10 epoxy groups, such as 2 to 5 epoxy groups, 2 to 4 epoxy groups, 2 to 3 epoxy groups. In some examples, the crosslinker comprises 2 epoxy groups.

In some examples, the crosslinking agent containing at least two epoxy groups has the formula:

(X)-(Y[Z-F] _m ) _n

formula IV

Wherein, in each (Y- [ Z-F)]_m) Y, Z and F are each independently selected such that

F is, for example, of the formula-CH (O) CR¹Epoxy groups of H, wherein R¹Selected from H and alkyl;

z is an alkylene group, and Z is an alkylene group,

y is selected from (i) a single bond, -O-, -C (= O) -O-, -O-C (= O) -, whereinmIs 1, or (ii) Y is NH _m2-WhereinmIs a number of 1 or 2, and,

nis at least 1, in some examples at least 2, in some examples 2 to 4,

and X is an organic group.

In some examples, the crosslinker of formula IV has at least two F groups.

In some examples, F is of the formula-CH (O) CR¹The epoxy group of H, and the epoxy group of H,wherein R is¹Is H.

X may comprise or be an organic group selected from optionally substituted alkylene, optionally substituted alkyl, optionally substituted aryl, optionally substituted arylalkyl, optionally substituted alkylaryl, isocyanurate and polysiloxane. X may comprise a polymeric component; in some examples, the polymeric component can be selected from the group consisting of polysiloxanes (e.g., poly (dimethylsiloxane)), polyalkenes (e.g., polyethylene or polypropylene), acrylates (e.g., methyl acrylate), and poly (alkylene glycols) (e.g., poly (ethylene glycol) and poly (propylene glycol)), and combinations thereof. In some examples, X comprises a polymeric backbone comprising a plurality of repeat units, each repeat unit covalently bonded to (Y- [ Z-F)]_m) Wherein Y, Z, F and m are as described herein. X may be a group selected from branched or straight chain C1-10 alkyl (e.g., methyl, ethyl, propyl, butyl, pentyl, hexyl), phenyl, methylene biphenyl, triphenylmethane, cyclohexane, and isocyanurate.

In some examples, Y is selected from the group consisting of a single bond, -O-, -C (= O) -O-, -O-C (= O) -,mis 1, and X is an organic group selected from alkylene (e.g., C1-10 alkylene), optionally substituted alkylene (e.g., C1-10 alkylene), aryl (e.g., C5-12 aryl), optionally substituted aryl (e.g., C5-12 aryl), arylalkyl (e.g., C6-20 arylalkyl), optionally substituted arylalkyl (e.g., C6-20 arylalkyl), alkylaryl (e.g., C6-20 alkylaryl), and optionally substituted alkylaryl (e.g., C6-20 alkylaryl). In some examples, Y is selected from the group consisting of a single bond, -O-, -C (= O) -O-, -O-C (= O) -,mis 1, and X is an organic group selected from the group consisting of alkylene, aryl, arylalkyl, and alkylaryl. In some examples, Y is selected from the group consisting of a single bond, -O-, -C (= O) -O-, -O-C (= O) -, and,mIs 1 and X is an organic group selected from C1-10 alkylene, C5-12 aryl, C6-20 arylalkyl and C6-20 alkylaryl. In some examples, Y is selected from a single bond, -O-, -C (= O) -O-, -O-C (= O) -, m is 1, and X is an organic group selected from C1-10 alkylene (e.g., methylene, ethylene, propylene, butylene, pentylene, hexylene, heptylene), phenyl, methylenebiphenyl, triphenylmethane, cyclohexane.

In some examples, X is selected from (i) an alkane, which may be an optionally substituted straight, branched or cyclic alkane, (ii) a C-substituted alkyl group having at least two substituents Y- [ Z-F]_m(ii) cycloalkane, and (iii) aryl (e.g., phenyl). In some examples, X is selected from (i) branched alkanes in which at least two alkyl branches are covalently bonded to (Y- [ Z-F)]_m) And (ii) has at least two substituents Y- [ Z-F]_m(ii) cycloalkane of (ii), and (iii) has at least two substituents Y- [ Z-F]_mAryl (e.g., phenyl); y is selected from (i) -O-, -C (= O) -O-, -O-C (= O) -, andmis 1, or (ii) Y is-NH_2-mWhereinmIs 1 or 2; z is C1-4 alkylene; f is a group of the formula-CH (O) CR¹Epoxy groups of H, wherein R¹Selected from H and methyl, and in some examples, F is of the formula-CH (O) CR¹Epoxy groups of H, wherein R¹Is H.

In some examples, X is Y- [ Z-F ] having at least two substituents] _m (i.e. thenIs at least 2) a linear alkane (e.g., hexylene); y is-O-andmis 1; z is C1-4 alkylene (e.g., methylene); and F is of the formula-CH (O) CR¹Epoxy groups of H, wherein R¹Selected from H and methyl, and in some examples, R¹Is H.

In some examples, Z-F is a glycidyl group. In some examples, the crosslinker comprises two glycidyl groups. In some examples, the crosslinker comprises two glycidyl ether groups bonded to each other via a linker, and the linker can be selected from the group consisting of an alkyl group, an optionally substituted alkyl group, an aryl group, and an optionally substituted aryl group.

In some examples, Z-F is epoxycycloalkyl. In some examples, Z-F is epoxycyclohexyl. In some examples, Z-F is epoxycyclohexyl, in some examples 3, 4-epoxycyclohexyl. In some examples, the crosslinker comprises two epoxycycloalkyl groups, in some examples two epoxycyclohexyl groups.

In some examples, the crosslinker comprises two epoxycycloalkyl groups bonded to each other via a linking group; and the linking group can be selected from the group consisting of a single bond, an optionally substituted alkyl group, an optionally substituted aryl group, an optionally substituted arylalkyl group, an optionally substituted alkylaryl group, an isocyanurate, a polysiloxane, -O-, -C (= O) -O-, -O-C (= O) -and an amino group, and combinations thereof. In some examples, the linker can be selected from the group consisting of alkylene, -O-, -C (= O) -O-, and-O-C (= O) -. In some examples, the linker can be selected from-C (= O) -O-and-O-C (= O) -.

In some examples, the epoxy-based crosslinker is selected from the DECH series of epoxy-based crosslinkers (including 3, 4-epoxycyclohexylmethyl 3, 4-epoxycyclohexanecarboxylate and 7-oxabicyclo [4.1.0] heptane-3-carboxylate 7-oxabicyclo [4.1.0] hept-3-ylmethyl ester) and tris (4-hydroxyphenyl) methane triglycidyl ether. In some examples, the epoxy-based crosslinking agent is selected from 3, 4-epoxycyclohexylmethyl 3, 4-epoxycyclohexanecarboxylate and 7-oxabicyclo [4.1.0] heptane-3-carboxylic acid 7-oxabicyclo [4.1.0] hept-3-ylmethyl ester, in some examples 7-oxabicyclo [4.1.0] heptane-3-carboxylic acid 7-oxabicyclo [4.1.0] hept-3-ylmethyl ester.

In some examples, the crosslinking agent containing at least two epoxy groups can be a diglycidyl ether. In some examples, a crosslinking agent containing at least two epoxy groups can be formed by the reaction of an epihalohydrin (e.g., epichlorohydrin) with a diol. In some examples, the diol is an alkyl diol.

In some examples, the crosslinker can be an alkyl polyol polyglycidyl ether, such as an alkyl diol diglycidyl ether or an alkyl triol triglycidyl ether. In some examples, the crosslinker can be selected from the group consisting of methylene glycol diglycidyl ether, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, butanediol diglycidyl ether, pentanediol diglycidyl ether, hexanediol diglycidyl ether (e.g., 1, 6-hexanediol diglycidyl ether), heptanediol glycidyl ether, octanediol diglycidyl ether, neopentyl glycol diglycidyl ether, cyclohexanedimethanol diglycidyl ether (e.g., 1, 4-cyclohexanedimethanol diglycidyl ether), resorcinol diglycidyl ether, trimethylolethane triglycidyl ether, trimethylolpropane triglycidyl ether, propoxylated glycol triglycidyl ether. In some examples, the crosslinking agent can be a hexanediol diglycidyl ether, such as 1, 6-hexanediol diglycidyl ether.

In some examples, the crosslinking agent may be selected from pentaerythritol polyglycidyl ether and sorbitol polyglycidyl ether.

In some examples, the crosslinker containing at least two epoxy groups is present in an amount of 20 wt.% or less of the solids of the radiation curable finish composition, for example 19 wt.% or less, 18 wt.% or less, 17 wt.% or less, 16 wt.% or less, 15 wt.% or less, 14 wt.% or less, 13 wt.% or less, 12 wt.% or less, 11 wt.% or less, or 10 wt.% or less of the solids of the radiation curable finish composition. In some examples, the crosslinker containing at least two epoxy groups is present in an amount of 0.5 wt.% or more of the solids of the radiation curable finish composition, such as 1 wt.% or more, 2 wt.% or more, 3 wt.% or more, 4 wt.% or more, 5 wt.% or more, 6 wt.% or more, 7 wt.% or more, 8 wt.% or more, 9 wt.% or more, or 10 wt.% or more of the solids of the radiation curable finish composition. In some examples, the crosslinker containing at least two epoxy groups is present in an amount of 0.5 to 20 weight percent of the total solids of the radiation curable finish composition, such as 1 to 20 weight percent, 2 to 19 weight percent, 3 to 18 weight percent, 4 to 17 weight percent, 5 to 16 weight percent, 6 to 15 weight percent, 7 to 14 weight percent, 8 to 13 weight percent, 9 to 12 weight percent, or 10 to 11 weight percent of the solids of the radiation curable finish composition.

Photoinitiator

The radiation curable finish composition may comprise a photoinitiator. The photoinitiator may be any suitable photoinitiator. The photoinitiator can be any photoinitiator conventionally used in radiation curable finish compositions. In some examples, the photoinitiator may be a type I photoinitiator, i.e., a photoinitiator that undergoes a unimolecular bond cleavage upon irradiation to generate a free radical, or a type II photoinitiator, i.e., a photoinitiator that undergoes a bimolecular reaction in which the excited state of the photoinitiator interacts with a second molecule (co-initiator) to generate a free radical. In some examples, the type I photoinitiator may be selected from benzoin esters, benzyl ketals, α -dialkoxyacetophenones, hydroxyalkylphenones, α -aminoalkylphenones, and acylphosphine oxides. In some examples, the type II photoinitiator may be selected from benzophenones/amines and thioxanthones/amines. In some examples, the photoinitiator may be benzophenone.

In some examples, the radiation curable finish composition comprises photoinitiator in an amount of 15 wt% or less, in some examples 12 wt% or less, in some examples 10 wt% or less, in some examples 7 wt% or less, in some examples 5 wt% or less, in some examples 4 wt% or less, in some examples 3 wt% or less, in some examples 2 wt% or less, in some examples 1 wt% or less, in some examples 0.5 wt% or less. In some examples, the radiation curable overcoat composition comprises photoinitiator in an amount of 0.001 wt% or greater, in some examples 0.01 wt% or greater, in some examples 0.1 wt% or greater, in some examples 0.2 wt% or greater, in some examples 0.5 wt% or greater, in some examples 1 wt% or greater, in some examples 2 wt% or greater, in some examples 3 wt% or greater, in some examples 4 wt% or greater, in some examples 5 wt% or greater. In some examples, the radiation curable finish composition comprises photoinitiator in an amount of 0.001 to 15 wt%, in some examples 0.01 to 10 wt%, in some examples 0.1 to 12 wt%, in some examples 3 to 12 wt%, in some examples 5 to 10 wt%.

Printed label substrate

In some examples, the radiation curable finish composition is applied to a printed label substrate. In some examples, the radiation curable finish composition is applied to a liquid electrostatically printed ink, i.e., a printed label substrate, disposed on the label substrate.

In some examples, the printed label substrate includes a label substrate and a liquid electrostatically printed ink disposed on the label substrate. In some examples, the printed label substrate may include a primer disposed between the label substrate and the liquid electrostatically printed ink. In some examples, a printed label substrate may include a label substrate, a primer disposed on the label substrate, and an electrostatically printed ink disposed on the primer.

In some examples, the printed label substrate may include an adhesive layer disposed on a surface of the label substrate opposite the electrostatically printed ink. In some examples, the label substrate may include an adhesive layer disposed on a surface of the label substrate opposite a surface on which the electrostatically printed ink will be disposed.

Label base

The label substrate may be any substrate suitable for use in a label. The label substrate may be any suitable substrate on which liquid xerographic ink can be printed. The label substrate may be any suitable substrate on which a primer (onto which a liquid xerographic ink may be printed) may be applied.

The label substrate may comprise a material selected from organic or inorganic materials. The label substrate may comprise a natural polymeric material, such as cellulose. The label substrate may comprise synthetic polymeric materials such as polymers formed from olefin monomers including, for example, polyethylene and polypropylene, and copolymers such as styrene-polybutadiene. In some examples, the polypropylene may be a biaxially oriented polypropylene.

In some examples, the label substrate may be or comprise a cellulosic substrate, such as a cellulosic paper. In some examples, the cellulosic substrate may be or comprise an uncoated cellulosic substrate, i.e., no coating of polymeric material is present. In some examples, a cellulosic substrate (which may be a cellulosic paper) is coated with a polymeric material, such as a polymer formed from a styrene-butadiene resin. In some examples, the cellulose paper has an inorganic material (prior to application of any primer layer) bonded to its surface with a polymeric material, wherein the inorganic material may be selected from, for example, kaolinite or calcium carbonate.

The label substrate may be or comprise an acrylic substrate, and in some examples, a coated acrylic substrate, for example coated with a styrene-butadiene copolymer.

In some examples, the label substrate may be a transparent label substrate. In some examples, the label substrate and the adhesive layer (which once affixed to the second substrate) may be transparent.

In some examples, the label substrate may comprise a polymeric material. In some examples, the polymeric material may comprise a transparent polymeric material. In some examples, the label substrate may comprise a film, such as a film, of polymeric material. In some examples, the polymeric material may comprise polymers formed from olefin monomers, including, for example, polyethylene and polypropylene, and copolymers, such as styrene-polybutadiene. In some examples, the polymeric material may comprise Polyethylene (PE), Linear Low Density Polyethylene (LLDPE), Low Density Polyethylene (LDPE), Medium Density Polyethylene (MDPE), High Density Polyethylene (HDPE), polypropylene (PP), cast (cPP) polypropylene or biaxially oriented polypropylene (BOPP), Oriented Polyamide (OPA), or polyethylene terephthalate (PET).

In some examples, the label substrate may comprise a polymeric material having a primer disposed thereon. In some examples, the printed label substrate may include a polymeric material having a primer disposed thereon, wherein the primer is disposed between the polymeric material and the liquid electrostatically printed ink.

In some examples, the label substrate may be or comprise a metal, which may be in the form of a sheet. In some examples, the label substrate may comprise a metal foil or a metallized substrate. In some examples, the label substrate may comprise metallized paper (i.e., paper having a metal layer thereon) or metallized plastic film (i.e., plastic film having a metal layer thereon). In some examples, the metal may be selected from or made of, for example, aluminum (Al), silver (Ag), tin (Sn), copper (Cu), or mixtures thereof. In some examples, the label substrate may comprise aluminum foil.

In some examples, the label substrate may include multiple layers of material, in some examples, multiple layers of film material laminated together. In some examples, the label substrate may comprise multiple layers of material selected from polymeric materials (e.g. polymeric materials selected from PE, LLDPE, MDPE, PP, BOPP, PET and OPA), metallic materials (e.g. metallic foils such as aluminium foil, or metallized films such as metallized PET (met-PET) or metallized BOPP (met-BOPP) or metallized paper (met-paper) or any other metallized substrate), paper and combinations thereof. In some examples, the label substrate comprises multiple film layers of polymeric material, such as a combination of films selected from PE, LLDPE, MDPE, PP, BOPP, PET and OPA, laminated together to form a pre-laminated label substrate. In some examples, the pre-laminated label substrate may include a metal layer, such as an aluminum layer. In some examples, the pre-laminated label substrate may comprise a paper-Al-PE, PET-Al-PE, BOPP-met-BOPP, or PET-PE laminate.

In some examples, the label substrate may comprise a metallized paper in the form of a paper substrate coated on at least one surface with a metal layer, for example an aluminium layer. In some examples, the label substrate may comprise a metallized polymeric film in the form of a polymeric substrate coated on at least one surface with a metal layer, such as an aluminum layer. In some examples, the label substrate comprises a metallized polymer film in the form of a metallized BOPP film or a metallized ET film.

In some examples, the label substrate may comprise a film of material, wherein the film has a thickness of 600 μm or less, in some examples 250 μm or less, in some examples 200 μm or less, in some examples 150 μm or less, in some examples 100 μm or less, in some examples 95 μm or less, in some examples 90 μm or less, in some examples 85 μm or less, in some examples 80 μm or less. In some examples, the film of material has a thickness of about 80 μm.

In some examples, the label substrate may comprise a film of material, wherein the film has a thickness of 5 μm or greater, in some examples, 10 μm or more, in some examples, 15 μm or more, in some examples 20 μm or more, in some examples 25 μm or more, in some examples 30 μm or more, in some examples 35 μm or more, in some examples 40 μm or more, in some examples 45 μm or more, in some examples, 50 μm or more, in some examples, 55 μm or more, in some examples 60 μm or more, in some examples 65 μm or more, in some examples, 70 μm or more, in some examples 75 μm or more, and in some examples 80 μm or more.

Adhesive layer

In some examples, the printed label may include an adhesive layer disposed on a surface of the printed label substrate opposite the electrostatically printed ink. In some examples, the printed label substrate may include an adhesive layer disposed on a surface of the label substrate opposite the electrostatically printed ink. In some examples, the label substrate may include an adhesive layer disposed on a surface of the label substrate opposite a surface on which the electrostatically printed ink will be disposed.

In some examples, the adhesive layer is applied to the surface of the label substrate prior to providing the printed label substrate to the method of providing a printed label. In some examples, the adhesive layer is applied to the surface of the label substrate before, during, or after the radiation curable finish composition is applied. In some examples, the adhesive layer is applied to the surface of the label substrate before, during, or after the application (i.e., printing) of the electrostatically printed ink. In some examples, the adhesive layer is applied to the surface of the label substrate before, during, or after the primer layer is applied to the surface of the label substrate.

In some examples, a removable release layer is applied to the adhesive layer. In some examples, the removable release layer is applied at the same time as the adhesive layer is applied. In some examples, the removable release layer is applied immediately after the adhesive layer is applied. In some examples, a removable release layer is applied after the adhesive layer is applied but before the next layer is applied to the opposite surface of the label substrate.

In some examples, the adhesive layer is a pressure sensitive adhesive layer, a heat sensitive adhesive layer, a contact adhesive layer, a dry adhesive layer (i.e., an adhesive that adheres upon drying), a radiation cured adhesive layer (e.g., a UV cured adhesive layer), or a moisture cured adhesive layer (e.g., an adhesive that cures by reaction with, for example, moisture present on a second surface to which the label is applied or adhered in use or in air). The pressure sensitive adhesive may be a hot melt pressure sensitive adhesive, for example a rubber based or acrylic based pressure sensitive adhesive. The adhesive may be based on a rubber-based hot melt composition, a solvent-based rubber adhesive, a solvent-based acrylic adhesive, or a solvent-based polyurethane adhesive. The adhesive may be emulsion type, such as emulsion acrylic adhesives.

In some examples, the adhesive layer is 100 μm or less in thickness, such as 90 μm or less in thickness, 80 μm or less in thickness, 70 μm or less in thickness, 60 μm or less in thickness, 50 μm or less in thickness, 40 μm or less in thickness, 30 μm or less in thickness, 20 μm or less in thickness, or 15 μm or less in thickness.

In some examples, the adhesive layer is 15 μm or more thick, 20 μm or more thick, 30 μm or more thick, 40 μm or more thick, 50 μm or more thick, 60 μm or more thick, 70 μm or more thick, 80 μm or more thick, 90 μm or more thick, and in some examples, 100 μm or more thick.

Primer coating

In some examples, the printed label substrate may include a primer disposed between the label substrate and the liquid electrostatically printed ink.

In some examples, the printed label substrate is provided by applying a primer to the label substrate, for example, to a surface of the label substrate, and then applying (i.e., printing) an electrostatic printing ink over the primer. A printed label substrate having an electrostatically printed ink disposed thereon and a primer disposed between the label substrate and the electrostatically printed ink is thus formed.

The primer may comprise a primer resin. When applied, the primer resin may comprise a crosslinkable primer resin. The primer resin in the printed label may comprise a crosslinked primer resin.

In the printed label, the primer resin may be a cross-linked primer resin. In the method of providing a printed label substrate, the primer resin may be a crosslinkable primer resin until after application of the primer resin. In the method of providing a printed label substrate, the primer resin may be a crosslinkable primer resin until after application of the radiation curable finish composition.

In some examples, the primer resin may be selected from hydroxyl-containing resins, carboxyl-containing resins, amine-based polymer formulations, and combinations thereof. In some examples, the hydroxyl containing resin may be selected from polyvinyl alcohol resins such as polyvinyl alcohol based polyvinyl butyral formulations (e.g., Butvar resin from Eastman), Vinnol (from Wacker polymers), cellulose derivative additives (from Eastman), polyester resins (e.g., Dynapol from Evonic), and hydroxyl containing polyurethane based formulations. In some examples, the carboxyl group-containing resin may be selected from olefin-based copolymerized acrylic or methacrylic acid copolymers, polyacrylic acid-based polymers, and polylactic acid-based polymers. In some examples, the copolymer is a copolymer of ethylene and an acid selected from acrylic acid or methacrylic acid, and in some examples, the acid selected from acrylic acid or methacrylic acid is present in the resin in an amount of 10 to 50 weight percent, in some examples 20 to 40 weight percent. In some examples, the amine-based polymer formulation may be selected from polyamines and polyethyleneimines (which are also known as polyethylenimines). The primer resin may be selected from polyvinyl alcohol resins, cellulose-based resins, polyesters, polyamines, polyethyleneimine resins, polyamide resins, polyurethanes, copolymers of olefin monomers with acrylic or methacrylic acid monomers, and polyacrylic polymers. In some examples, the amine-based polymer formulation may include polyethyleneimine (also known as polyethylenimine). In some examples, the primer may include polyethyleneimine in an amount from 1 wt% to 20 wt%, in some examples, from 2 wt% to 15 wt%, in some examples, from 3 wt% to 10 wt%. In some examples, the primer may include polyethyleneimine in an amount of up to 10 wt%.

In some examples, the primer resin comprises a carboxyl functional group, an amine functional group, or a polyol functional group, or a combination thereof. In some examples, the primer resin comprises amine functional groups or carboxyl functional groups.

In some examples, the primer resin comprises an amine functional group. In some examples, the primer resin comprises or consists of a polyethyleneimine resin.

The resin may be crosslinked with a crosslinking agent, for example a crosslinking agent selected from the group consisting of melamine formaldehyde resins, phenolic resins, polyethyleneimines and Zn and Zr complexes.

Examples of materials suitable as primers include Michelman DigiPrime @orMichelman DigiPrime @ 030.

In some examples, the primer on the printed label substrate of the printed label comprises a crosslinked primer resin.

In some examples, such that the coat weight of the primer on the label substrate is 0.01 g/m²Or higher, in some examples, 0.05 g/m²Or higher, in some examples, 0.1 g/m²Or higher, and in some examples, 0.14 g/m²Or higher, and in some examples, 0.15 g/m²Or higher, and in some examples, about 0.18 g/m²The amount of primer applied or applied. In some examples, such that the coat weight of the primer resin on the label substrate is at most about 0.2 g/m²And, in some examples, up to about 0.5 g/m²In some examples, up to about 1 g/m²In some examples, up to about 1.5 g/m²The amount of primer applied or applied.

Electrostatically printed inks

In some examples, the printed label substrate has an electrostatically printed ink disposed thereon. In some examples, the printed label substrate has printed ink disposed thereon, which may be electrostatically printed ink.

In some examples, the printed label substrate is provided by applying (i.e., printing) an electrostatically printed ink on the label substrate, for example, on a surface of the label substrate. Thereby forming a printed label substrate having the electrostatically printed ink disposed thereon.

In some examples, the electrostatically printed ink may be such that the coat weight of the electrostatically printed ink measured on the surface of the label substrate is at least 0.01 g/m²In some examples, at least 0.05 g/m²In some examples, at least 0.1 g/m²In some examples, at least 0.5 g/m²In some examples, at least about 1 g/m²Is present in an amount. In some examples, the electrostatically printed ink may be such that the coat weight of the electrostatically printed ink measured on the surface of the label substrate is at most about 16 g/m²In some examples, up to about 10 g/m²In some examples, up to about 5 g/m²In some examples, up to about 4 g/m²Is present in an amount.

Electrostatic printing ink

Electrostatic printing, such as liquid electrostatic printing, is one method that can be used to print images or information onto a substrate, such as a label substrate. The electrostatic printing process generally involves making an image on a photoconductive surface, applying a liquid electrostatic ink or dry toner having charged particles to the photoconductive surface to selectively bind them to the image, and then transferring the charged particles in the form of the image to a substrate, such as a label substrate.

The xerographic ink may be electrostatically printed onto the label substrate. In some examples, the electrostatically printed ink may be electrostatically printed onto the label substrate, thereby forming an electrostatically printed ink. In some examples, the xerographic ink may be electrostatically printed onto a primer that has been applied to the label substrate.

The electrostatic printing ink may comprise a thermoplastic resin. The xerographic ink may comprise a crosslinkable thermoplastic resin. The electrostatically printed ink (i.e. the electrostatically printed ink after having been electrostatically printed) may comprise a crosslinked thermoplastic resin. In printed labels, the electrostatically printed ink may comprise a crosslinked thermoplastic resin.

In some examples, the electrostatic printing ink may be a liquid electrostatic printing ink. In some examples, the electrostatically printed ink may once be a liquid electrostatically printed ink.

The electrostatically printed ink disposed on the surface of the label substrate may have been printed using a liquid electrostatic printing process. In some examples, the xerographic ink may comprise a colorant or pigment and a thermoplastic resin. In some examples, the electrostatic printing ink may be a liquid electrostatic printing ink that may include a colorant or pigment, a thermoplastic resin, and a carrier liquid. The liquid electrostatic printing ink may further comprise additives such as charge directors, charge adjuvants, surfactants, viscosity modifiers, emulsifiers and the like.

In some examples, the colorant is a pigment. In some examples, the liquid xerographic ink may be free of any pigment, or may comprise a substantially zero pigment and thus be a pigment-free composition, which may be used to provide a particular transparent gloss or sheen to the label substrate.

In some examples, after printing, the liquid electrostatic printing ink (i.e., the liquid electrostatically printed ink) may comprise a reduced amount of carrier liquid as compared to the liquid electrostatic printing ink before printing. In some examples, the liquid electrostatically printed ink may be substantially free of a carrier liquid. Substantially free of carrier liquid may mean that the printed ink contains 5 wt% or less, in some examples 2 wt% or less, in some examples 1 wt% or less, in some examples 0.5 wt% or less of carrier liquid. In some examples, the electrostatically printed ink is free of a carrier liquid. Each of these components of an electrostatic printing ink is described separately in the following subsection.

Thermoplastic resin the thermoplastic resin may be referred to as a polymer resin or a thermoplastic polymer. In some examples, the thermoplastic resin of the xerographic ink comprises a carboxyl functional group, an amine functional group, a polyol functional group, or a combination thereof. In some examples, the thermoplastic resin of the xerographic ink comprises carboxyl functional groups. In some examples, the thermoplastic resin of the xerographic ink comprises amine functionality. In some examples, the thermoplastic resin of the xerographic ink comprises a polyol functional group.

In some examples, the thermoplastic resin comprises or consists of a polymer having acidic side groups. In some examples, the acidic side groups may be in the free acid form or may be in the anionic form and associate with a counterion, typically a metal counterion, for example a metal selected from alkali metals such as lithium, sodium and potassium, alkaline earth metals such as magnesium or calcium, and transition metals such as zinc.

In some examples, the thermoplastic resin may be a copolymer of an olefin monomer and a monomer selected from acrylic acid and methacrylic acid. The thermoplastic resin having acidic side groups may be selected from resins such as copolymers of ethylene and ethylenically unsaturated acrylic or methacrylic acid; and ionomers thereof, such as methacrylic acid and ethylene-acrylic acid or methacrylic acid copolymers at least partially neutralized with metal ions (e.g., Zn, Na, Li), such as SURLYN ionomers. The thermoplastic resin comprising acidic side groups can be a copolymer of ethylene and ethylenically unsaturated acrylic or methacrylic acid, wherein the ethylenically unsaturated acrylic or methacrylic acid can comprise from 5 to about 25 weight percent of the copolymer, and in some examples from 10 to about 20 weight percent of the copolymer.

In some examples, the thermoplastic resin of the electrostatic printing ink comprises a polyolefin copolymer, a polyethylene co-acrylic copolymer, a polyethylene co-methacrylic copolymer, a polyethylene co-vinyl acetate copolymer, an ionomer, or a combination thereof. In some examples, the thermoplastic resin of the electrostatic printing ink comprises or consists of an olefin acrylic or methacrylic resin, a polyurethane resin, a polyethyleneimine resin, a polyamide resin, a polyvinyl alcohol resin, and combinations thereof.

In some examples, the thermoplastic resin may comprise an ethylene or propylene acrylic acid copolymer; ethylene or propylene methacrylic acid copolymers; ethylene vinyl acetate copolymers; copolymers of ethylene or propylene (e.g., 80 to 99.9 wt.%) and alkyl (e.g., C1 to C5) esters of methacrylic or acrylic acid (e.g., 0.1 to 20 wt.%); copolymers of ethylene (e.g., 80 to 99.9 wt%), acrylic acid or methacrylic acid (e.g., 0.1 to 20.0 wt%), and alkyl (e.g., C1 to C5) esters of methacrylic acid or acrylic acid (e.g., 0.1 to 20 wt%); copolymers of ethylene or propylene (e.g., 70 to 99.9 wt.%) and maleic anhydride (e.g., 0.1 to 30 wt.%); polyethylene; polystyrene; isotactic polypropylene (crystalline); copolymers of ethylene ethyl acrylate; a polyester; polyvinyl toluene; a polyamide; styrene/butadiene copolymers; an epoxy resin; acrylic resins (e.g., copolymers of acrylic or methacrylic acid and at least one alkyl acrylate or methacrylate, wherein the alkyl group can have from 1 to about 20 carbon atoms), such as methyl methacrylate (e.g., from 50 to 90 wt%)/methacrylic acid (e.g., from 0 to 20 wt%)/ethylhexyl acrylate (e.g., from 10 to 50 wt%); ethylene-acrylate terpolymer: ethylene-acrylate-Maleic Anhydride (MAH) or Glycidyl Methacrylate (GMA) terpolymers; an ethylene-acrylic acid ionomer, or a combination thereof.

The thermoplastic resin may comprise a polymer having acidic side groups. The polymer having acidic side groups can have an acidity of 50 mg KOH/g or greater, in some examples 60 mg KOH/g or greater, in some examples 70 mg KOH/g or greater, in some examples 80 mg KOH/g or greater, in some examples 90 mg KOH/g or greater, in some examples 100 mg KOH/g or greater, in some examples 105 mg KOH/g or greater, in some examples 110 mg KOH/g or greater, in some examples 115 mg KOH/g or greater. The polymer having acidic side groups can have an acidity of 200 mg KOH/g or less, in some examples 190 mg KOH/g or less, in some examples 180 mg KOH/g or less, in some examples 130 mg KOH/g or less, in some examples 120 mg KOH/g or less. Polymer acidity in mg KOH/g can be measured using standard procedures, for example using the procedure described in ASTM D1386.

The thermoplastic resin may comprise a polymer having acidic side groups that has a melt flow rate of about 70 g/10 minutes or less, in some examples about 60 g/10 minutes or less, in some examples about 50 g/10 minutes or less, in some examples about 40 g/10 minutes or less, in some examples 30 g/10 minutes or less, in some examples 20 g/10 minutes or less, in some examples 10 g/10 minutes or less. In some examples, all polymers having acidic side groups and/or ester groups in the particles each independently have a melt flow rate of 90 g/10 min or less, in some examples 80 g/10 min or less, in some examples 70 g/10 min or less, in some examples 60 g/10 min or less.

The polymer having acidic side groups can have a melt flow rate of from about 10 g/10 min to about 120 g/10 min, in some examples from about 10 g/10 min to about 70 g/10 min, in some examples from about 10 g/10 min to about 40 g/10 min, in some examples from about 20 g/10 min to about 30 g/10 min. The polymer having acidic side groups may have a melt flow rate of, in some examples, about 50 g/10 min to about 120 g/10 min, in some examples, about 60 g/10 min to about 100 g/10 min. Melt flow rate can be measured using, for example, standard procedures as described in ASTM D1238.

The acidic side groups may be in the free acid form or may be in the anionic form and are associated with a counterion, typically a metal counterion, for example selected from alkali metals such as lithium, sodium and potassium, alkaline earth metals such as magnesium or calcium, and transition metals such as zinc. The thermoplastic resin having acidic side groups may be selected from resins such as copolymers of ethylene and ethylenically unsaturated acrylic or methacrylic acid; and ionomers thereof, such as methacrylic acid and ethylene-acrylic acid or methacrylic acid copolymers at least partially neutralized with metal ions (e.g., Zn, Na, Li), such as SURLYN ionomers. The polymer comprising acidic side groups can be a copolymer of ethylene and ethylenically unsaturated acrylic or methacrylic acid, wherein the ethylenically unsaturated acrylic or methacrylic acid comprises from 5% to about 25% by weight of the copolymer, and in some examples from 10% to about 20% by weight of the copolymer.

The thermoplastic resin may comprise two different polymers having acidic side groups. The two polymers having acidic side groups may have different acidity which may fall within the ranges mentioned above. The thermoplastic resin can comprise a first polymer having acidic side groups having an acidity of from 10 to 110 mg KOH/g, in some examples, from 20 to 110 mg KOH/g, in some examples, from 30 to 110 mg KOH/g, in some examples, from 50 to 110 mg KOH/g, and a second polymer having acidic side groups having an acidity of from 110 to 130 mg KOH/g.

The thermoplastic resin may comprise two different polymers having acidic side groups: a first polymer having acidic side groups having a melt flow rate of from about 10 g/10 min to about 50 g/10 min and an acidity of from 10 mg KOH/g to 110 mg KOH/g, in some examples, from 20 mg KOH/g to 110 mg KOH/g, in some examples, from 30 mg KOH/g to 110 mg KOH/g, in some examples, from 50 mg KOH/g to 110 mg KOH/g, and a second polymer having acidic side groups having a melt flow rate of from about 50 g/10 min to about 120 g/10 min and an acidity of from 110 mg KOH/g to 130 mg KOH/g. The first and second polymers may be free of ester groups.

In some examples, the ratio of the first polymer having acidic side groups to the second polymer having acidic side groups can be about 10:1 to about 2: 1. In some examples, the ratio can be about 6:1 to about 3:1, and in some examples, about 4: 1.

The thermoplastic resin may comprise a polymer having a melt viscosity of 15000 poise or less, in some examples, 10000 poise or less, in some examples, 1000 poise or less, in some examples, 100 poise or less, in some examples, 50 poise or less, in some examples, 10 poise or less; the polymer may be a polymer having acidic side groups as described herein. The thermoplastic resin may comprise a first polymer having a melt viscosity of 15000 poise or more, in some examples 20000 poise or more, in some examples 50000 poise or more, in some examples 70000 poise or more; and in some examples, the polymer resin may comprise a second polymer having a melt viscosity that is lower than the melt viscosity of the first polymer, in some examples, 15000 poise or less, in some examples, 10000 poise or less, in some examples, 1000 poise or less, in some examples, 100 poise or less, in some examples, 50 poise or less, and in some examples, 10 poise or less. The thermoplastic resin may comprise a first polymer having a melt viscosity of greater than 60000 poise, in some examples, 60000 poise to 100000 poise, in some examples, 65000 poise to 85000 poise; a second polymer having a melt viscosity of 15000 poise to 40000 poise, in some examples 20000 poise to 30000 poise, and a third polymer having a melt viscosity of 15000 poise or less, in some examples 10000 poise or less, in some examples 1000 poise or less, in some examples 100 poise or less, in some examples 50 poise or less, in some examples 10 poise or less; an example of a first polymer is Nucrel 960 (from DuPont), an example of a second polymer is Nucrel 699 (from DuPont), and an example of a third polymer is AC-5120 or AC-5180 (from Honeywell). The first, second and third polymers may be polymers having acidic side groups as described herein. A rheometer, such as the commercially available AR-2000 rheometer from Thermal Analysis Instruments, can be used, using geometry: melt viscosity was measured by taking a plate-to-plate rheology isotherm at 120 ℃ at a shear rate of 0.01 hz for a 25 mm steel plate-standard steel parallel plate.

If the thermoplastic resin comprises a single type of polymer, the polymer (excluding any other components of the electrostatic ink composition) may have a melt viscosity of 6000 poise or more, in some examples, 8000 poise or more, in some examples, 10000 poise or more, and in some examples, 12000 poise or more. If the thermoplastic resin comprises multiple polymers, all of the polymers of the thermoplastic resin may together form a mixture (excluding any other components of the electrostatic ink composition) having a melt viscosity of 6000 poise or more, in some examples, 8000 poise or more, in some examples, 10000 poise or more, and in some examples, 12000 poise or more. Melt viscosity can be measured using standard techniques. A rheometer, such as the commercially available AR-2000 rheometer from Thermal Analysis Instruments, can be used, using geometry: melt viscosity was measured by taking a plate-to-plate rheology isotherm at 120 ℃ at a shear rate of 0.01 hz for a 25 mm steel plate-standard steel parallel plate.

The thermoplastic resin may comprise two different polymers having acidic side groups selected from copolymers of ethylene and ethylenically unsaturated acrylic or methacrylic acid; or ionomers thereof, such as methacrylic acid and ethylene-acrylic acid or methacrylic acid copolymers at least partially neutralized with metal ions (e.g., Zn, Na, Li), such as SURLYN ionomers. The thermoplastic resin can comprise (i) a first polymer that is a copolymer of ethylene and an ethylenically unsaturated acrylic or methacrylic acid, wherein the ethylenically unsaturated acrylic or methacrylic acid comprises from 8 to about 16 weight percent of the copolymer, in some examples from 10 to 16 weight percent of the copolymer; and (ii) a second polymer that is a copolymer of ethylene and an ethylenically unsaturated acrylic or methacrylic acid, wherein the ethylenically unsaturated acrylic or methacrylic acid comprises from 12% to about 30% by weight of the copolymer, in some examples from 14% to about 20% by weight of the copolymer, in some examples from 16% to about 20% by weight of the copolymer, and in some examples from 17% to 19% by weight of the copolymer.

The thermoplastic resin may comprise a polymer having acidic side groups (which may be free of ester side groups) and a polymer having ester side groups, as described above. The polymer having ester side groups may be a thermoplastic polymer. The polymer having ester side groups may further comprise acidic side groups. The polymer having ester side groups may be a copolymer of a monomer having ester side groups and a monomer having acidic side groups. The polymer may be a copolymer of a monomer having an ester side group, a monomer having an acidic side group, and a monomer without any acidic side group and ester side group. The monomer having an ester side group may be a monomer selected from esterified acrylic acid or esterified methacrylic acid. The monomer having acidic side groups may be a monomer selected from acrylic acid or methacrylic acid. The monomer without any acidic and ester side groups may be an olefin monomer including, for example, ethylene or propylene. The esterified acrylic acid or esterified methacrylic acid may be an alkyl ester of acrylic acid or an alkyl ester of methacrylic acid, respectively. The alkyl group in the alkyl ester of acrylic or methacrylic acid may be an alkyl group having 1 to 30 carbon atoms, in some examples 1 to 20 carbon atoms, in some examples 1 to 10 carbon atoms; in some examples, selected from methyl, ethyl, isopropyl, n-propyl, tert-butyl, isobutyl, n-butyl, and pentyl.

The polymer having ester side groups can be a copolymer of a first monomer having ester side groups, a second monomer having acidic side groups, and a third monomer that is an olefin monomer without any acidic and ester side groups. The polymer having ester side groups can be a copolymer of (i) a first monomer having ester side groups selected from esterified acrylic or methacrylic acids, in some examples alkyl esters of acrylic or methacrylic acid, (ii) a second monomer having acidic side groups selected from acrylic or methacrylic acid, and (iii) a third monomer that is an olefin monomer selected from ethylene and propylene. The first monomer may constitute 1 to 50 weight percent, in some examples 5 to 40 weight percent, in some examples 5 to 20 weight percent, and in some examples 5 to 15 weight percent of the copolymer. The second monomer may constitute 1 to 50 weight percent of the copolymer, in some examples 5 to 40 weight percent of the copolymer, in some examples 5 to 20 weight percent of the copolymer, and in some examples 5 to 15 weight percent of the copolymer. In some examples, the first monomer comprises 5 to 40 weight percent of the copolymer, the second monomer comprises 5 to 40 weight percent of the copolymer, and the third monomer comprises the remaining weight of the copolymer. In some examples, the first monomer comprises 5 to 15 weight percent of the copolymer, the second monomer comprises 5 to 15 weight percent of the copolymer, and the third monomer comprises the remaining weight of the copolymer. In some examples, the first monomer comprises 8 to 12 weight percent of the copolymer, the second monomer comprises 8 to 12 weight percent of the copolymer, and the third monomer comprises the remaining weight of the copolymer. In some examples, the first monomer comprises about 10% by weight of the copolymer, the second monomer comprises about 10% by weight of the copolymer, and the third monomer comprises the remaining weight of the copolymer. The polymer may be selected from the group consisting of Bynel ® type polymers, including Bynel 2022 and Bynel 2002, available from DuPont @.

The polymer having ester side groups may constitute 1 wt% or more of the total amount of resin polymers, e.g., thermoplastic resins, in the liquid electrostatic ink composition and/or the electrostatic ink printed on the primer layer, e.g., the total amount of the polymer having acidic side groups and the polymer having ester side groups. In the liquid electrostatic ink composition and/or the electrostatic ink printed on the primer layer, the polymer having ester side groups may constitute 5% by weight or more of the total amount of the resin polymer, i.e., the thermoplastic resin polymer, in some examples, 8% by weight or more of the total amount of the resin polymer, e.g., the thermoplastic resin polymer, in some examples, 10% by weight or more of the total amount of the resin polymer, e.g., the thermoplastic resin polymer, in some examples, 15% by weight or more of the total amount of the resin polymer, e.g., the thermoplastic resin polymer, in some examples, 20% by weight or more of the total amount of the resin polymer, e.g., the thermoplastic resin polymer, in some examples, 25% by weight or more of the total amount of the resin polymer, e.g., the thermoplastic resin polymer, in some examples, 30% by weight or more of the total amount of the resin polymer, in some examples, the resin polymer, e.g., thermoplastic resin polymer, is 35 wt% or more of the total amount. The polymer having ester side groups may constitute from 5 wt% to 50 wt% of the total amount of the resin polymer, e.g., thermoplastic resin polymer, in the liquid electrostatic ink composition and/or the electrostatic ink composition printed on the primer layer, in some examples from 10 wt% to 40 wt% of the total amount of the thermoplastic resin polymer, in some examples from 5 wt% to 30 wt% of the total amount of the resin polymer, e.g., thermoplastic resin polymer, in the liquid electrostatic ink composition and/or the ink composition printed on the primer layer, in some examples from 5 wt% to 15 wt% of the total amount of the resin polymer, in the liquid electrostatic ink composition and/or the ink composition printed on the primer layer, in some examples, the resin polymer, e.g., thermoplastic resin polymer, in the liquid electrostatic ink composition and/or the ink composition printed on the primer layer is 15 wt% to 30 wt% of the total amount.

The polymer having ester side groups can have an acidity of 50 mg KOH/g or greater, in some examples, 60 mg KOH/g or greater, in some examples, 70 mg KOH/g or greater, in some examples, 80 mg KOH/g or greater. The polymer having ester side groups can have an acidity of 100 mg KOH/g or less, and in some examples, 90 mg KOH/g or less. The polymer having ester side groups can have an acidity of 60 to 90 mg KOH/g, and in some examples, 70 to 80 mg KOH/g.

The polymer having ester side groups can have a melt flow rate of about 10 g/10 min to about 120 g/10 min, in some examples about 10 g/10 min to about 50 g/10 min, in some examples about 20 g/10 min to about 40 g/10 min, in some examples about 25 g/10 min to about 35 g/10 min.

One or more polymers, one or more copolymers of thermoplastic resins may be selected, in some examples, from the group consisting of resins of the Nucrel series (e.g., Nucrel 403. sup.,. Nucrel 407. sup.,. Nucrel 609 HS. sup.,. Nucrel 908 HS. sup.,. Nucrel 1202 HC. sup.,. Nucrel 30707. sup.,. Nucrel 1214. sup.,. Nucrel 903. sup.,. Nucrel # Nucrel # and/or. ES, Nucrel # Nucrel # LR.,. sup.,. 5H, Nucrel # Nucrel # nu.,. sup.,.

The polymeric resin may constitute from about 5 to 90 weight percent, in some examples, from about 50 to 80 weight percent of the solid body of the liquid electrostatic ink composition and/or the ink composition printed on the label substrate. The resin may constitute about 60 to 95% by weight, in some examples about 70 to 95% by weight, of the solid body of the liquid electrostatic ink composition and/or the ink composition printed on the primer layer.

Colorants the electrostatically printed ink may comprise a colorant. The electrostatic printing ink may comprise a colorant. The colorant may be a dye or a pigment. The colorant can be any colorant that is compatible with the liquid carrier and is useful for electrostatic printing. For example, the colorant may be present as pigment particles, or may comprise a resin (other than the resins described herein) and a pigment. The resins and pigments may be any resins and pigments that are used in standard practice. In some examples, the colorant is selected from a cyan pigment, a magenta pigment, a yellow pigment, and a black pigment. For example, pigments produced by Hoechst, including Yoghuang DHG, Yoghuang GR, Yoghuang G, Yoghuang NCG-71, Yoghuang GG, Hansa Yellow RA, Hansa Brilliant Yellow 5GX-02, Hansa Yellow X, NOVAPERM YELLOW HR, NOVAPERM YELLOW FGL, Hansa Brilliant Yellow 10GX, Yoghuang G3R-01, HOSTAPERM YELLOW H4G, HOSTAPERM YELLOW H3G, HOSTAPERM ORANGE GR, HOSTAPERM SCARLET, Permanent Rubin F6B; pigments manufactured by Sun Chemical, including L74-1357 Yellow, L75-1331 Yellow, L75-2337 Yellow; pigments produced by Heubach, comprising DALAMAR YELLOW YT-858-D; pigment produced by Ciba-Geigy, comprising CromopHAL YELLOW 3G, CROMOPHTHAL YELLOW GR, CROMOPHTHAL YELLOW 8G, IRGAZINE YELLOW 5GT, IRGALITE RUBINE 4BL, MONASTRAL MAGE NTA, MONASTRAL SCARLET, MONASTRAL VIOLET, MONASTRAL RED, MONASTRAL VIOLET; BASF produced pigment, including LUMOGEN LIGHT YELLOW, PALIOGEN ORANGE, HELIOGEN BLUE L690 IF, HELIOGEN BLUE TBD 7010, HELIOGEN BLUE K7090, HELIOGEN BLUE L710 IF, HELIOGEN BLUE L6470, HELIOGEN GREEN K8683, HELIOGEN GREEN L9140; mobay produced pigments comprising QUINDO MAGENTA, INDOAST BRILLIANT SCARLET, QUINDO RE ® granulesD6700, QUINDO RED 6713, INDOAST VIOLET; the pigment produced by Cabot comprises Maroon B STERLING NS BLACK, STERLING NSX 76 and MOGUL L; the pigment produced by DuPont comprises TIPURE R-101; and pigments produced by Paul Uhlich, comprising UHLICH BK 8200. In some examples, the pigment may be a white pigment. If the pigment is a white pigment particle, the pigment particle may be selected from TiO₂Calcium carbonate, zinc oxide and mixtures thereof. In some examples, the white pigment particles may comprise alumina-TiO₂A pigment.

In some examples, the colorant or pigment particles may have a median particle size or d of 20 μm or less, such as 15 μm or less, such as 10 μm or less, such as 5 μm or less, such as 4 μm or less, such as 3 μm or less, such as 2 μm or less, such as 1 μm or less, such as 0.9 μm or less, such as 0.8 μm or less, such as 0.7 μm or less, such as 0.6 μm or less, such as 0.5 μm or less, or d₅₀. Unless otherwise indicated, the particle sizes of the colorant or pigment particles and the resin-coated pigment particles were determined by using laser diffraction on a Malvern Mastersizer 2000 according to standard procedures as described in the operating manual.

The colorant or pigment particles may be present in the electrostatic ink composition in an amount of 10 to 80 weight percent, in some examples 15 to 60 weight percent, in some examples 15 to 50 weight percent, in some examples 15 to 40 weight percent, in some examples 15 to 30 weight percent of the total amount of resin and colorant. In some examples, the colorant or pigment particles may be present in the electrostatic ink composition in an amount of at least 50% by weight of the total amount of resin and colorant or pigment, such as at least 55% by weight of the total amount of resin and colorant or pigment.

Carrier liquid the xerographic ink may comprise a carrier liquid before and during printing of the xerographic ink. In general, the carrier liquid can serve as a dispersion medium for other components in the xerographic ink. For example, the carrier liquid may comprise or be a hydrocarbon, silicone oil, vegetable oil, or the like. The carrier liquid may be containedIncluding, but not limited to, insulating non-polar non-aqueous liquids that can be used as a medium for toner particles. The carrier liquid may comprise a liquid having a viscosity of greater than about 10⁹A resistivity of about ohm ∙ cm. The carrier liquid may have a dielectric constant of less than about 5, and in some examples less than about 3. The carrier liquid may include, but is not limited to, hydrocarbons. The hydrocarbons may include, but are not limited to, aliphatic hydrocarbons, isomerized aliphatic hydrocarbons, branched chain aliphatic hydrocarbons, aromatic hydrocarbons, and combinations thereof. Examples of carrier liquids include, but are not limited to, aliphatic hydrocarbons, isoparaffins, paraffin compounds, dearomatized hydrocarbon compounds, and the like. In particular, carrier fluids may include, but are not limited to, Isopar-G, Isopar-H, Isopar-L, Isopar-M, Isopar-K, Isopar-V, Norpar 12, Norpar 13, Norpar 15, Exxol D40, Exxol D80, Exxol D100, Exxol D130 and Exxol D140 (each sold by EXXON CORATION); a Telen N-16, a Telen N-20, a Telen N-22, a Nisseki Naphthol L-tract, a Nisseki Naphthol M-tract, a Nisseki Naphthol H-tract, #0 Solvent L-tract, #0 Solvent M-tract, #0 Solvent H-tract, a Nisseki lsosol 300-tract, a Nisseki lsosol 400-tract, an AF-4-tract, an AF-5-tract, an AF-6-tract and an AF-7-tract (each sold by NIPPON OIL CORPORATION); an IP Solvent 1620 and an IP Solvent 2028 (each sold by IDEMITSU PETROCHEMICAL CO., LTD.); amsco OMS and Amsco 460 (each sold by AMERICAN MINERAL SPIRITS CORP.); and Electron, Positron, New II, Purogen HF (100% synthetic terpenes) (sold by ECOLINK ™).

Prior to electrostatic printing, the carrier liquid may constitute about 20 wt% to 99.5 wt% of the electrostatic printing ink, in some examples 60 wt% to 99.5 wt% of the electrostatic printing ink. The carrier liquid may constitute about 40% to 90% by weight of the electrostatic printing ink prior to printing. The carrier liquid may constitute about 60% to 80% by weight of the electrostatic printing ink prior to printing. The carrier liquid may comprise about 90 wt% to 99.5 wt% of the electrostatic printing ink prior to printing, in some examples 95 wt% to 99 wt% of the electrostatic printing ink.

The electrostatically printed ink, when electrostatically printed (i.e. electrostatically printed ink), may be substantially free of carrier liquid. During and/or after the electrostatic printing process, the carrier liquid may be removed, for example by electrophoresis and/or evaporation during the printing process, to transfer substantially only the solid to the label substrate. Substantially free of carrier liquid may mean that the ink printed on the label substrate contains 5 wt% or less, in some examples 2 wt% or less, in some examples 1 wt% or less, in some examples 0.5 wt% or less of carrier liquid. In some examples, the electrostatically printed ink on the label substrate is free of a carrier liquid.

Charge director liquid electrostatic printing inks and/or electrostatically printed inks may comprise a charge director. Charge directors can be added to the electrostatic printing ink to provide a charge of a desired polarity and/or to maintain a sufficient electrostatic charge on the particles of the electrostatic printing ink. The charge director may comprise ionic compounds including, for example, metal salts of fatty acids, metal salts of sulfosuccinates, metal salts of oxyphosphoric acids, metal salts of alkyl-benzenesulfonic acids, metal salts of aromatic carboxylic or sulfonic acids, as well as zwitterionic and nonionic compounds such as polyoxyethylated alkylamines, lecithin, polyvinylpyrrolidone, organic acid esters of polyhydric alcohols, and the like. The charge director may be selected from the group consisting of oil soluble petroleum sulfonates (e.g., neutral Calcium Petronate, neutral Barium Petronate, and basic Barium Petronate), polybutylene succinimides (e.g., OLOA 1200 and Amoco 575) and glyceryl ester salts (e.g., sodium salts of phosphorylated mono-and diglycerides having unsaturated and saturated acid substituents), sulfonates, including, for example, Barium, sodium, Calcium, and aluminum salts of sulfonic acids. The sulfonic acids may include, for example, alkyl sulfonic acids, aryl sulfonic acids, and alkyl succinic acid esters. The charge director can impart a negative or positive charge to the resin-containing particles of the xerographic ink.

The charge director may comprise the general formula [ R ]_a-O-C(O)CH₂CH(SO₃ ⁻)C(O)-O-R_b]The sulfosuccinate moiety of (a), wherein R_aAnd R_bEach is an alkyl group. In some examples, the charge director comprises a simple salt and formula MA_nSodium salt of sulfosuccinic acid ester salt of (1)Rice grains, wherein M is a metal, n is the valence of M, and A is of the formula [ R_a-O-C(O)CH₂CH(SO₃ ⁻)C(O)-O-R_b]Wherein R is_aAnd R_bEach is an alkyl group, or other charge director. General formula MA_nThe sulfosuccinate salt of (a) is an example of a micelle-forming salt. The charge director may be substantially free or free of an acid of the general formula HA, wherein a is as described above. The charge director may comprise micelles of said sulfosuccinate salt encapsulating at least some of the nanoparticles. The charge director may comprise at least some nanoparticles having a size of 200 nanometers or less, and in some examples 2 nanometers or more. Simple salts are salts that do not form micelles by themselves, although they may form the core of a micelle with a micelle-forming salt. The ions that make up the simple salts are completely hydrophilic. The simple salt may comprise a metal selected from Mg, Ca, Ba, NH₄Tert-butylammonium, Li⁺And Al⁺³Or a cation selected from any subgroup thereof. The simple salt may comprise a salt selected from SO₄ ^2-、PO^3-、NO^3-、HPO₄ ^2-、CO₃ ^2-Acetate, Trifluoroacetate (TFA), Cl^-、Br^-、BF₄ ^-、F^-、ClO₄ ^-And TiO₃ ^4-Or an anion selected from any subgroup thereof. The simple salt may be selected from CaCO₃、Ba₂TiO₃、Al₂(SO₄)、Al(NO₃)₃、Ca₃(PO₄)₂、BaSO₄、BaHPO₄、Ba₂(PO₄)₃、CaSO₄、(NH₄)₂CO₃、(NH₄)₂SO₄、NH₄OAc, tert-butyl ammonium bromide, NH₄NO₃、LiTFA、Al₂(SO₄)₃、LiClO₄And LiBF₄Or any subgroup thereof. The charge director may further comprise basic barium petroleum sulfonate (BBP).

In the formula [ R_a-O-C(O)CH₂CH(SO₃ ⁻)C(O)-O-R_b]In some examples, R_aAnd R_bEach is an aliphatic alkyl group. In some examples, R_aAnd R_bEach independently is C_6-25An alkyl group. In some examples, the aliphatic alkyl group is linear. In some examples, the aliphatic alkyl group is branched. In some examples, the aliphatic alkyl group comprises a straight chain having 6 or more carbon atoms. In some examples, R_aAnd R_bThe same is true. In some examples, R_aAnd R_bAt least one of is C₁₃H₂₇. In some examples, M is Na, K, Cs, Ca, or Ba.

The charge director may comprise (i) soy lecithin, (ii) a barium sulfonate salt, such as basic barium petroleum sulfonate (BPP), and (iii) isopropylamine sulfonate. Basic barium petroleum sulfonate is a barium sulfonate salt having hydrocarbon alkyl chains of 21-26 carbon atoms and is available, for example, from Chemtura. An exemplary isopropylamine sulfonate is isopropylamine dodecylbenzene sulfonate available from Croda.

In an electrostatic printing ink, the charge director may constitute from about 0.001% to 20%, in some examples, from 0.01 to 10%, in some examples, from 0.01 to 1% by weight of the solid bodies of the electrostatic printing ink and/or the electrostatic printing ink. The charge director may constitute about 0.001 to 0.15% by weight, in some examples 0.001 to 0.15% by weight, of the solid bodies of the liquid electrostatic printing ink and/or the electrostatically printed ink, in some examples 0.001 to 0.02% by weight of the solid bodies of the liquid electrostatic printing ink and/or the electrostatically printed ink. In some examples, the charge director imparts a negative charge to the xerographic ink. The particle conductivity can be 50 to 500 pmho/cm, in some examples 200-350 pmho/cm.

Charge adjuvant liquid electrostatic printing inks and/or electrostatically printed inks may comprise a charge adjuvant. The charge adjuvant may be present with and may be different from the charge director and is used to increase and/or stabilize the charge on particles, such as resin-containing particles of an electrostatic printing ink. The charge adjuvant may include barium petroleum sulfonate, calcium petroleum sulfonate, Co salt of naphthenic acid, Ca salt of naphthenic acid, Cu salt of naphthenic acid, Mn salt of naphthenic acid, Ni salt of naphthenic acid, Zn salt of naphthenic acid, Fe salt of naphthenic acid, Ba salt of stearic acid, Co salt of stearic acid, Pb salt of stearic acid, Zn salt of stearic acid, Al salt of stearic acid, Cu salt of stearic acid, Fe salt of stearic acid, metal carboxylate (e.g., aluminum tristearate, aluminum octoate, lithium heptylate, ferric stearate, ferric distearate, barium stearate, chromium stearate, magnesium octoate, calcium stearate, ferric naphthenate, zinc naphthenate, manganese heptylate, zinc heptanoate, barium octoate, aluminum octoate, cobalt octoate, manganese octoate, and zinc octoate), cobalt linoleate, manganese linoleate, lead linoleate, zinc linoleate, calcium oleate, cobalt oleate, zinc palmitate, calcium resinate, cobalt resinate, manganese resinate, calcium naphthenate, zinc, Lead resinate, zinc resinate, AB diblock copolymers of 2-ethylhexyl methacrylate-co-calcium methacrylate and ammonium salts, copolymers of alkyl acrylamidoglycolate alkyl ethers (e.g., methyl acrylamidoglycolate methyl ether-co-vinyl acetate), and hydroxy bis (3, 5-di-tert-butylsalicylic acid) aluminate monohydrate (hydroxy bis (3,5-di-tert-butyl salicylic acid) aluminate. In some examples, the charge adjuvant is aluminum di-or tristearate and/or aluminum di-and/or tripalmitate.

The charge adjuvant may constitute about 0.1 to 5% by weight of the solid body of the liquid electrostatic printing ink and/or the electrostatically printed ink. The charge adjuvant may constitute about 0.5 to 4% by weight of the solid body of the liquid electrostatic printing ink and/or the electrostatically printed ink. The charge adjuvant may constitute about 1 to 3% by weight of the solid body of the liquid electrostatic printing ink and/or the electrostatically printed ink.

Other additives in some examples, the xerographic ink and/or the xerographic ink may comprise one or more additives. The one or more additives may be added at any stage of the production of the xerographic ink. The one or more additives may be selected from waxes, surfactants, biocides, organic solvents, viscosity modifiers, pH adjusting materials, chelating agents, preservatives, compatibility additives, emulsifiers, and the like. The wax may be an incompatible wax. As used herein, "incompatible wax" may refer to a wax that is incompatible with the resin. Specifically, after transferring the ink film (e.g., from an intermediate transfer member, which may be a heated blanket) onto the label substrate, the wax phase separates from the resin phase as the resin frit mixture cools.

Method for producing printed labels

Described herein is a method of providing a printed label comprising: applying a radiation curable finish composition to a liquid electrostatically printed ink disposed on the label substrate; wherein the radiation curable finish composition comprises: radiation curable monomers and/or oligomers; a photoinitiator; a polyalkylsiloxane containing at least two reactive functional groups, wherein the reactive functional groups are selected from the group consisting of hydrogen, hydroxyl, amino, and double bonds; and a crosslinking agent containing at least two epoxy groups.

Examples of the methods described herein are schematically depicted in fig. 1,2 and 3, where the features shown are designated using the following reference numerals: the reference numeral "1" refers to a printed label; reference numeral "2" refers to the label substrate; reference numeral "3" refers to an electrostatically printed ink or an electrostatically printed ink; reference numeral "5" refers to a printed label substrate; the reference numeral "4" refers to a radiation curable finish composition or a radiation curable finish composition; reference numeral "6" denotes a primer; and reference numeral "10" refers to an adhesive that may be applied (at any stage of the process) to the surface of the label substrate opposite the surface to which the xerographic ink is applied or will be applied, or may have been applied to the label substrate prior to the commencement of the process.

Fig. 1 depicts a method of providing a printed label substrate (5) having an electrostatically printed ink (3) disposed thereon. Applying a radiation curable finish composition (4) onto the printed ink (3) disposed on the label substrate, wherein the radiation curable finish composition comprises radiation curable monomers and/or oligomers; a photoinitiator; a polyalkylsiloxane containing at least two reactive functional groups, wherein the reactive functional groups are selected from the group consisting of hydrogen, hydroxyl, amino, and double bonds; and a crosslinking agent containing at least two epoxy groups. In some examples, the radiation curable finish composition is then cured using radiation. In some examples, curing of the radiation curable finish composition results in polymerization of the radiation curable monomers and/or oligomers. In some examples, curing of the radiation curable overcoat composition causes polymerization of the radiation curable monomers and/or oligomers and a crosslinking reaction with any unreacted functional groups within the electrostatically printed ink.

In some examples, the radiation curable finish composition can be applied by any suitable technique. In some examples, the radiation curable finish composition is applied by gravure coating, flexographic coating, screen coating, or xerography. In some examples, the radiation curable finish composition can be applied using an in-line (in-line) method of electrostatic printing with an electrostatic printing ink.

In some examples, the method comprises applying a corona treatment to the surface of the printed label substrate (5) prior to applying the radiation curable finish composition.

In some examples, the light is generated by light (photoinitiation), such as visible light or ultraviolet light; heat (heat-induced); electron beam (electron beam initiated); ionizing radiation, such as gamma radiation (gamma initiation); non-ionizing radiation, such as microwave radiation (microwave initiation); or any combination thereof, initiates and/or promotes the curing of the radiation curable finish composition. In some examples, curing of the radiation curable finish composition is initiated by light. In some examples, curing of the radiation curable finish composition is initiated by ultraviolet light. In some examples, the radiation is emitted by a radiation source, such as an ultraviolet light source. In some examples, the ultraviolet light source may be a UV lamp or a UV bulb.

In some examples, the ultraviolet light has an output power of 10,000W or less, in some examples 9000W or less, in some examples 8000W or less, in some examples 7000W or less, in some examples 6000W or less, in some examples 5000W or less, in some examples 4000W or less, in some examples 3000W or less, in some examples 2500W or less, in some examples 2000W or less, in some examples 1500W or less. In some examples, the ultraviolet light has an output power of 500W or greater, optionally 600W or greater, optionally 700W or greater, optionally 800W or greater, optionally 900W or greater, optionally 1000W or greater, optionally 2000W or greater, optionally 3000W or greater, optionally 4000W or greater, optionally 5000W or greater. In some examples, the ultraviolet light has an output power of 500 to 10,000W, in some examples 600 to 9000W, in some examples 700 to 8000W, in some examples 800 to 7000W, in some examples 900 to 6000W, in some examples 1000 to 5000W. In some instances, UV output power may refer to power received by a UV source, such as a UV lamp or UV bulb, and/or power consumed by the UV source in emitting UV radiation, and may also be referred to as input intensity.

In some examples, the ultraviolet light has a density of 70 mJ/cm²Or less, and in some examples, 60 mJ/cm²Or less, and in some examples, 50 mJ/cm²Or less, and in some examples, 40 mJ/cm²Or less, and in some examples, 30 mJ/cm²Or less, and in some examples, 20 mJ/cm²Or, in some examples, 15 mJ/cm²The output intensity at the surface of the substrate, i.e., the effective energy at the surface (sometimes referred to as dose). In some examples, the finish composition cures at 1 mJ/cm under UV irradiation²Or greater, and in some examples, 2 mJ/cm²Or greater, and in some examples, 3 mJ/cm²Or greater, and in some examples, 4 mJ/cm²Or greater, or in some examples, 5 mJ/cm²Or greater UV output intensity at the substrate surface. In some examples, the finish composition cures at 1 mJ/cm under UV irradiation²To 70 mJ/cm²In some examples, 2 mJ/cm²To 60 mJ/cm²In some examples, 3 mJ/cm²To 50 mJ/cm²In some examples, 4 mJ/cm²To 40 mJ/cm²In some examples, 5 mJ/cm²To 30 mJ/cm²In some examples, 5 mJ/cm²To 20 mJ/cm²Or, in some examples, 5 mJ/cm²To 15 mJ/cm²UV output intensity of (a).

In some examples, the method comprises applying a corona treatment to the printed label substrate prior to applying the radiation curable finish composition. In some examples, corona treatment may improve the surface polarity of a substrate, such as a printed label substrate. During corona treatment, polar groups, such as hydroxyl, ketone, and carboxyl groups, may be grafted onto the surface of a substrate, such as the surface of a printed label substrate. The corona treatment may be performed in a corona chamber at room temperature and atmospheric pressure. In some examples, the corona density may be 500W or greater, such as 600W or greater, 700W or greater, 800W or greater, 900W or greater, 1000W or greater. In some examples, the corona density may be 1500W or less, such as 1400W or less, 1300W or less, 1200W or less, 1100W or less, 1000W or less. In some examples, the corona density may be 500W to 1500W, such as 600W to 1400W, 700W to 1300W, 800W to 1200W, 900W to 1100W, 500W to 1000W, 1000W to 1500W.

Fig. 2 depicts a method of providing a label substrate (2). Electrostatically printing an electrostatically printed ink (3) onto a label substrate (2) to form a printed label substrate (5) having the electrostatically printed ink (3) disposed thereon. A radiation curable overcoat composition (4) is then applied to the printed ink (3), wherein the radiation curable overcoat composition is as described herein. In some examples, the radiation curable finish composition is then cured using radiation. In some examples, curing of the radiation curable finish composition results in polymerization of the radiation curable monomers and/or oligomers of the radiation curable finish composition.

In some examples, electrostatically printing the electrostatically printing ink onto the label substrate may comprise printing any of the electrostatically printing inks described herein by any suitable electrostatic printing process. In some examples, electrostatically printing the electrostatic printing ink onto the label substrate may comprise liquid electrostatically printing a liquid electrostatic printing ink onto the label substrate. In some examples, electrostatically printing the electrostatic printing ink onto the label substrate may comprise electrostatically printing a liquid electrostatic printing ink liquid onto the label substrate using a liquid electrostatic printing device. An example of a suitable liquid electrostatic printing device is an HP Indigo digital printer.

Fig. 3 depicts a method of providing a label substrate (2). A primer (6) is applied to the label substrate. The electrostatically printed ink (3) is then electrostatically printed onto the label substrate (2) to form a printed label substrate (5) having the electrostatically printed ink (3) disposed thereon. A radiation curable overcoat composition (4) is then applied to the printed ink (3), wherein the radiation curable overcoat composition is as described herein. In some examples, the radiation curable finish composition is then cured using radiation. In some examples, curing of the radiation curable finish composition results in polymerization of the radiation curable monomers and/or oligomers of the radiation curable finish composition.

In some examples, the primer may be applied by any suitable technique. In some examples, the primer is applied by gravure coating, flexographic coating, screen coating, or xerography. In some examples, the primer may be applied using an in-line process of electrostatic printing with an electrostatic printing ink.

Radiation curable finish composition

The radiation curable finish composition may comprise radiation curable monomers and/or oligomers; a photoinitiator; a polyalkylsiloxane containing at least two reactive functional groups, wherein the reactive functional groups are selected from the group consisting of hydrogen, hydroxyl, amino, and double bonds; and a crosslinking agent containing at least two epoxy groups. The components of the radiation curable finish composition can be as described herein.

Ink and finish paint set

An ink and finish set is also provided. The ink and finish set can comprise a liquid electrostatic printing ink composition; and a radiation curable finish composition. The ink and finish set can comprise a liquid electrostatic printing ink composition; and a radiation curable finish composition comprising radiation curable monomers and/or oligomers; a photoinitiator; a polyalkylsiloxane containing at least two reactive functional groups, wherein the reactive functional groups are selected from the group consisting of hydrogen, hydroxyl, amino, and double bonds; and a crosslinking agent containing at least two epoxy groups.

Examples

The following illustrates embodiments of the materials, methods, and related aspects described herein. Thus, these examples should not be construed as limiting the disclosure, but are merely examples of how the compositions of the disclosure can be practiced. Accordingly, a number of representative compositions and methods of making the same are disclosed herein.

Material

Primer coating

DigiPrime @ (available from Michelman) comprises a cross-linkable branched polyethyleneimine resin (10 wt%) having a molecular weight of about 50000 in water.

Liquid electrostatic ink composition

ElectroInk 4.5 (available from HP Indigo) comprises a 4:1 ratio of Nucrel 699 (a copolymer of ethylene and methacrylic acid with a nominal 11 wt% methacrylic acid) and A-C5120 (a copolymer of ethylene and acrylic acid with an acrylic acid content of 15 wt%), a pigment, a charge adjuvant (VCA ™), and a charge director (NCD) in Isopar. L.

Finishing paint composition

DIGICOAT, matte high abrasion (scuff) varnish (UXH 00090405N; available from the Flint Group) comprises ethoxylated trimethylolpropane triacrylate; dipropylene glycol diacrylate; polysiloxane acrylate hexamethylene diacrylate; a monoester of acrylic acid with propane-1, 2-diol and a photoinitiator.

DMS-S33 (available from ABCR) comprises silanol-terminated polydimethylsiloxane, has a molecular weight of 43,500 g/mol, a kinematic viscosity of 3500 cSt and 0.8 wt% OH groups.

Erisys. TM. GE-25 contains 1, 6-hexanediol diglycidyl ether.

EXAMPLE 1 (REFERENCE)

A label substrate comprising a primer disposed on a surface of the label substrate and a liquid electrostatically printed ink disposed on the primer was prepared by providing a label substrate comprising Polypropylene (Polypropylene White available from Nirotech; 80 μm thick) primed with DigiPrime 050 using an HP Indigo WE6600 liquid electrostatic printer comprising an in-line priming system, followed by liquid electrostatic printing with ElectroInk 4.5.

A UV curable overcoat composition (DIGICOAT @, matte high abrasion varnish) was applied to the printed ink and cured using an ABG coating system containing an anilox roller (from SANDON) having 200 lines/inch (78.74 lines/cm) using a coating speed of 25 m/min, a UV lamp (from GEW) output of 5000W, and a corona density of 1000W. The coating weight, measured gravimetrically, was about 4 g/m². The resulting printed labels were tested as follows.

Example 2 (reference; silanol-terminated polyalkylsiloxane)

Printed labels were prepared as described in example 1, except that the UV-curable finish composition was prepared by mixing DMS-S33 (12.5 g) with DIGICOAT ™ varnish (587.5 g).

Example 3 (reference; crosslinking agent containing a Diepoxy group)

Printed labels were prepared as described in example 1, except that the UV-curable finish composition was prepared by mixing Erysis GE-25 (60 g) with DIGICOAT ™ varnish (540 g).

Example 4

Printed labels were prepared as described in example 1, except that a UV curable finish composition was prepared by mixing DMS-S33 (12.5 g; containing silanol-terminated polydimethylsiloxane) and Erysis GE-25 (60 g; containing 1, 6-hexanediol diglycidyl ether) with DIGICOAT ™ varnish (527.5 g).

Example 5 (reference)

A printed label was prepared as described in example 1, except that the label substrate was Polypropylene Clear (available from Nirotech; 80 μm thick).

Example 6 (reference; silanol-terminated polyalkylsiloxane)

A printed label was prepared as described in example 2, except that the label substrate was Polypropylene Clear (available from Nirotech; 80 μm thick).

Example 7 (reference; crosslinking agent containing di-epoxy groups)

A printed label was prepared as described in example 3, except that the label substrate was Polypropylene Clear (available from Nirotech; 80 μm thick).

Example 8

A printed label was prepared as described in example 4, except that the label substrate was Polypropylene Clear (available from Nirotech; 80 μm thick).

Test of

Mechanical resistance

An unprinted label is applied to the bottle. A printed label is applied to a second bottle. The two bottles are slid against each other with the label against the label, under a pressure of 6 to 8 kg, up to 10 times.

After each repetition, the printed labels were inspected for visible wear marks. The results were ranked to classify the visible wear scar after 1 to 5 replicates as poor, the visible wear scar after 6 to 10 replicates as medium, and the no damage after 10 replicates as good.

Water scratch resistance test

The printed label was immersed in water at room temperature for 20 hours. The printed label was then removed from the water and wiped dry before the scratch test was performed. The labels are scored using coins under a load of approximately 2 to 5 kg.

The labels were visually inspected for damage and rated as poor (total area scratched), medium (up to 50% of the area scratched) or good (no scratch).

Peeling test

The peel test was considered inadequate because the tape did not stick to the label surface to which the polyalkylsiloxane had been applied.

Results table

	Amount of Polyalkylsiloxane [ wt.%]	Amount of crosslinking agent [ wt.%]	Mechanical resistance	Wet scratch resistance
					Ex.1 (reference)	–	–	Difference (D)	Difference (D)
Ex.2 (reference)	2.5	–	Good effect	Medium and high grade
					Ex.3 (reference)	–	10	Difference (D)	Good effect
Ex.4	2.5	10	Good effect	Good effect
					Ex.5 (reference)	–	–	Difference (D)	Difference (D)
Ex.6 (reference)	2.5	–	Good effect	Difference (D)
					Ex.7 (reference)	–	10	Difference (D)	Medium and high grade
Ex.8	2.5	10	Good effect	Good effect

As can be seen from the results table, the printed labels made according to examples 4 and 8 (comprising a finish composition comprising a diepoxide crosslinker and a silanol-terminated polyalkylsiloxane) exhibited the best water resistance and mechanical resistance.

Fig. 4 shows the effect of a mechanical resistance test on printed labels made according to a) example 1 and b) example 4, the left hand bottle in each figure showing a wear mark on a green liquid electrostatic ink (printed at 350% coverage, formed from 100% cyan, 100% yellow, 50% black and 100% white) and the right hand bottle in each figure showing a wear mark on a magenta liquid electrostatic ink.

Fig. 5 shows the effect of a wet scratch resistance test on printed labels made according to a) example 4, b) example 3 and c) example 1. Each patch of the label substrate is printed with a different color of liquid electrostatic ink composition (from top to bottom: black, magenta, cyan, green, and yellow).

While the method, printed label, and related aspects have been described with reference to certain embodiments, those skilled in the art will recognize that various modifications, changes, omissions, and substitutions can be made without departing from the spirit of the disclosure. It is intended, therefore, that the method, printed label, and related aspects be limited by the scope of the following claims. Features of any dependent claim may be combined with features of any other dependent claim and any other independent claim, unless stated otherwise.