阅读说明：本技术 基材上的可印刷涂层 (Printable coating on a substrate ) 是由 D·C·麦克尔拉思 M·L·洛霍夫 A·E·诺伊鲍尔 L·M·阿勒斯 T·G·多勒富特 于 2019-03-29 设计创作，主要内容包括：本公开涉及一种印刷吸收制品和用于制造印刷吸收制品的方法。具体地讲,在吸收制品的外覆层上的印刷可通过使用疏水基材并将包含颜料的水性油墨涂覆到吸墨涂层来实现,所述吸墨涂层的厚度为约0.1毫米或更小,并且基重为至少2gsm,其中所述涂层以零度或约零度的接触角从所述油墨吸收液体,此时所述油墨以至少500英尺/分钟的印刷速度被印刷到所述疏水基材上。(The present disclosure relates to a printed absorbent article and a method for manufacturing a printed absorbent article. In particular, printing on the outer cover of an absorbent article can be accomplished by using a hydrophobic substrate and applying an aqueous ink comprising a pigment to a blotting coating having a thickness of about 0.1 millimeters or less and a basis weight of at least 2gsm, wherein the coating absorbs liquid from the ink with a contact angle of zero degrees or about zero degrees when the ink is printed onto the hydrophobic substrate at a print speed of at least 500 feet per minute.)

1. A printed absorbent article comprising:

a hydrophobic substrate;

an ink-receptive coating, wherein the ink-receptive coating has a thickness of about 0.1 millimeters or less and a basis weight of about 2gsm to about 18 gsm; and coating with

An aqueous ink comprising a pigment, wherein the coating absorbs liquid from the ink at a contact angle of zero degrees or about zero degrees when the ink is printed through the coating onto the substrate at a print speed of at least about 500 feet per minute.

2. The printed absorbent article according to claim 1, wherein the coating has a thickness of about 0.0015 millimeters and a basis weight of about 3 gsm.

3. The printed absorbent article of claim 1, wherein the substrate is a polyolefin or a plastic film.

4. The printed absorbent article of claim 1, wherein the substrate comprises paper, wood, woven fabric, textile, plastic, glass, metal, foil, or a combination thereof.

5. The printed absorbent article of claim 1, wherein the ink receptive coating comprises talc, cellulosic fibers, superabsorbent amorphous silica, or combinations thereof.

6. The printed absorbent article of claim 1, wherein the ink-receptive coating comprises a surfactant.

7. The printed absorbent article of claim 1, wherein the printing speed is about 1400 feet per minute and up to about 2000 feet per minute.

8. The printed absorbent article of claim 1, wherein the amount of aqueous ink applied to the substrate through the coating depends on the amount of ink required to draw a graphic, pattern, or number on the substrate.

9. The printed absorbent article of claim 1, wherein the amount of aqueous ink absorbed by the coating is the same after the aqueous ink is applied to the substrate.

10. The printed absorbent article of claim 1, wherein the printed absorbent article is packaged for commercial sale.

11. A printing method for making a printed absorbent article comprising the steps of:

applying an ink-receptive coating to a substrate, wherein the coating has a thickness of about 0.1 millimeters or less and a basis weight of about 2gsm to about 18gsm, and

applying an aqueous ink comprising a pigment to a hydrophobic substrate through the ink receptive coating at a print speed of at least about 500 feet per minute, wherein the coating absorbs liquid from the ink at a contact angle of zero degrees or about zero degrees.

12. The printing method for making a printed absorbent article according to claim 11, wherein the coating has a thickness of about 0.0015 millimeters and a basis weight of about 3 gsm.

13. The printing method for making a printed absorbent article of claim 11, wherein the substrate is a polyolefin or a plastic film.

14. The printing method for making a printed absorbent article according to claim 11, wherein the substrate comprises paper, wood, woven fabric, textile, plastic, glass, metal, foil, or a combination thereof.

15. The printing method for making a printed absorbent article according to claim 11, wherein the ink receptive coating comprises talc, cellulosic fibers, superabsorbent amorphous silica, or combinations thereof.

16. The printing process for making a printed absorbent article according to claim 11, wherein the ink receptive coating comprises a surfactant.

17. The printing method for making a printed absorbent article according to claim 11, wherein the printing speed may be about 1000, about 1400, or about 2000 feet per minute.

18. The printing process for making a printed absorbent article according to claim 11, wherein the amount of aqueous ink applied to the substrate through the coating depends on the amount of ink required to draw a graphic, pattern, or number on the substrate.

19. The printing method for making a printed absorbent article according to claim 11, wherein the amount of aqueous ink absorbed by the coating is the same after the aqueous ink is coated onto the substrate.

20. The printing method for making a printed absorbent article according to claim 11, wherein the printed absorbent article is packaged for commercial sale.

Background

Polymers are widely used in the manufacture of a variety of products, including blown and cast films, extruded sheets, injection molded articles, foams, blow molded articles, extruded tubing, monofilaments, fibers and nonwoven fabrics. Many of the polymers used to form these products, such as polyolefins, are naturally hydrophobic or non-polar and chemically inert. For many applications, hydrophobicity is a disadvantage, particularly when printing with water-based inks having a relatively higher surface tension than the surface energy of the polymeric substrate. For example, the water-based ink can have a surface tension of greater than or equal to 45 dynes/cm, while the polymeric substrate can have a surface tension of about 30 dynes/cm. Surface tension is the force holding the fluids together. Surface tension directly affects whether the coating will wet and spread on or retract from the substrate (beading). While substrate hydrophobicity may not be an issue for lower surface tension inks or solvent-based inks, the non-polar nature of the polymeric substrate still does not promote good adhesion of these aqueous or solvent-based inks to the polymeric substrate, resulting in printed graphics that will be easily rubbed off when subjected to shear forces.

Generally, the polymers used to form these products are poorly polar, resulting in their inability to adhere to the most commonly used ink compositions applied to the surface of the polymeric substrate. Furthermore, these polymers are generally non-absorbent and do not form a mechanically strong network with the ink composition after it is applied to the polymeric substrate.

Hydrophobic polymers, including polyolefins such as polyethylene and polypropylene, are useful in the manufacture of polymeric fabrics used in the construction of packaging articles and disposable absorbent articles such as diapers, feminine care products, incontinence products, training pants, wipes, and the like. Such polymeric fabrics are typically nonwoven fabrics prepared by, for example, meltblowing processes, carding processes, co-forming processes, spunbonding processes, and combinations thereof.

Absorbent articles, especially personal care absorbent articles such as pantiliners, sanitary napkins, interlabial devices, adult incontinence devices, bandages, wipes, diapers, training pants, and swim pants, typically include an outer cover made of a nonwoven polymer fabric, or alternatively, the outer cover is made by printing on a plastic film and then laying a nonwoven material on top of the printed plastic film. For example, the outer covers of diapers, training pants, and swim pants are difficult to print in a quick and economical manner suitable for efficient machine production.

Therefore, there is a need to improve the adhesion of ink to the outer cover of the absorbent article by increasing the printing speed. The present disclosure meets this need by utilizing a method in which a pattern and/or graphic can be printed directly onto a small pore size or non-porous nonwoven substrate, or alternatively, a pattern/graphic is printed onto a plastic film and then a nonwoven material is placed on top of the printed film. The new methods disclosed herein can achieve fast printing speeds of at least 500 feet per minute or more without the use of a drying step, thereby reducing manufacturing process time and cost.

Disclosure of Invention

The present disclosure relates to a printed absorbent article and a method for manufacturing a printed absorbent article. In particular, printing on a hydrophobic substrate may be achieved by applying an aqueous ink comprising a pigment to a blotting coating having a thickness of about 0.1 millimeters (mm) or less, and more preferably having a thickness of about 0.0015mm, a basis weight of about 2gsm to about 4gsm and about 2gsm to about 3gsm, wherein the coating absorbs liquid from the ink at a contact angle of zero degrees or about zero degrees when the ink is printed onto the absorbent article at a print speed of at least 500 feet per minute.

In one embodiment of the present disclosure, a printed absorbent article includes

A hydrophobic substrate; an ink-receptive coating, wherein the ink-receptive coating has a thickness of about 0.1 millimeters or less and a basis weight of about 2gsm to about 18 gsm; and applying an aqueous ink comprising a pigment, wherein the coating absorbs liquid from the ink at a contact angle of zero degrees or about zero degrees when the ink is printed through the coating onto the substrate at a print speed of at least about 500 feet per minute.

In another embodiment of the present disclosure, a printing process for making a printed absorbent article comprises the steps of: applying a blotting coating to a substrate, wherein the coating has a thickness of about 0.1 millimeters or less and a basis weight of about 2gsm to about 18gsm, and applying an aqueous ink comprising a pigment to the substrate through the blotting coating at a print speed of at least about 500 feet per minute, wherein the coating absorbs liquid from the ink with a contact angle of zero degrees or about zero degrees

Drawings

The disclosure may be more completely understood in consideration of the following detailed description of various embodiments in connection with the accompanying drawings, in which:

fig. 1A-B show a comparison between two disposable absorbent articles, where the left absorbent article shows that wet ink has been transferred to the back of the print surface when wound into a roll in the absence of an ink receptive coating. And wherein the right side absorbent article is shown as a disposable absorbent article without any ink transfer to the back side due to the presence of the ink receptive coating.

Fig. 2A-B show a comparison between two disposable absorbent articles, where the left absorbent article shows that wet ink has been transferred to the back of the print surface when wound into a roll in the absence of an ink receptive coating. And wherein the right side absorbent article is shown as a disposable absorbent article without any ink transfer to the back side due to the presence of the ink receptive coating.

Detailed Description

When introducing elements of the present disclosure or the preferred embodiments thereof, the articles "a," "an," and "the" are intended to mean that there are one or more of the elements.

The terms "comprising," "including," and "having" are intended to be inclusive and mean that there may be additional elements other than the listed elements.

The term "absorbent article" refers to devices that absorb and contain body exudates and, more specifically, refers to devices that are placed against or in proximity to the body of the wearer to absorb and contain the various exudates discharged from the body. Absorbent articles may include diapers, training pants, adult incontinence undergarments, feminine hygiene products, breast pads, care pads, bibs, wound dressing products, and the like. As used herein, the term "bodily exudates" includes, but is not limited to, urine, blood, vaginal secretions, breast milk, perspiration, and feces.

The term "nonwoven" is a sheet, web or felt made of oriented or randomly oriented fibers bonded by friction and/or cohesion and/or adhesion, excluding paper and products of bonded yarns or filaments that are bonded by weaving, knitting, tufting, stitch bonding, or felted by wet milling, whether or not additionally needled. The nonwoven material may comprise a spunlace nonwoven material. The fibers may be of natural or man-made origin and may be staple or continuous filaments or formed in situ. Commercially available fibers range in diameter from less than about 0.001mm to greater than about 0.2mm, and they come in several different forms: staple fibers (referred to as cut or chopped), continuous single fibers (filaments or monofilaments), untwisted continuous filament bundles (tows), and twisted continuous filament bundles (yarns). Nonwoven fabrics can be formed by a number of processes such as, for example, meltblowing processes, spunbonding processes, solvent spinning processes, electrospinning processes, and carding processes. The basis weight of nonwoven fabrics is typically expressed in grams per square meter (gsm).

The term "substrate" includes any material on which the ink of the present invention can be printed. Thus, the substrate of the present invention includes, but is not limited to, a nonwoven material, a film, a fibrous polyolefin web, a cellulosic web, an elastomeric web, a laminate of one or more of the foregoing, or any combination of one or more of the foregoing.

Absorbent article

Referring to fig. 1A-B and 2A-B, an absorbent article is disclosed, wherein the absorbent article includes an absorbent chassis. The absorbent chassis defines a front waist region, a back waist region, a crotch region interconnecting the front waist region and the back waist region, an inner surface configured to contact a wearer, and an outer surface opposite the inner surface configured to contact a garment of the wearer. The printing disclosed herein occurs on the outer surface of the absorbent article, wherein the hydrophobic substrate is coated directly onto the outer surface. The absorbent article described in US 6,849,067 is incorporated herein.

The outer surface (or outer cover) desirably comprises a substantially liquid impermeable material, and may be elastic, stretchable or nonstretchable. The outer cover may be a single layer of liquid impermeable material but desirably comprises a multi-layer laminate structure in which at least one layer is liquid impermeable. For example, the outer surface may include a liquid permeable outer layer and a liquid impermeable inner layer that are suitably joined together by a laminating adhesive (not shown). Suitable laminating adhesives are available from findley adhesives, inc., Wauwatosa, wis., u.s.a. or from National Starch and Chemical Company, Bridgewater, n.j.u.s.a., which may be applied as beads, sprays, parallel swirls, etc., in a continuous or intermittent manner. The liquid permeable outer layer may be any suitable material and is desirably a material that provides a generally cloth-like texture. One example of such a material is a 20gsm (grams per square meter) spunbond polypropylene nonwoven web. While the outer cover need not be liquid permeable, it desirably provides the wearer with a relatively cloth-like texture.

The inner layer of the outer surface may be both liquid and vapor impermeable, or may be liquid impermeable and vapor permeable. The inner layer is desirably made of a thin plastic film, although other flexible liquid impermeable materials may also be used. The inner layer or liquid impermeable outer surface, when a single layer, prevents waste from wetting articles such as bed sheets and clothing, as well as the wearer and caregiver. A suitable liquid impermeable film for use as the liquid impermeable inner layer or the single liquid impermeable outer surface is a 1.0 mil polyethylene film commercially available from Edison Plastics Company, South Plainfield, n.j., u.s.a. If the outer surface is a single layer of material, it may be embossed and/or matte finished to provide a more cloth-like appearance. As mentioned earlier, the liquid impermeable material can allow vapors to escape from the interior of the disposable absorbent article while still preventing liquids from passing through the outer surface. Suitable "breathable" materials are composed of microporous polymeric films or nonwoven fabrics that are coated or otherwise treated to impart a desired level of liquid impermeability. Suitable microporous membranes are PMP-1 membrane materials commercially available from Mitsui Toatsu Chemicals, Inc., Tokyo, Japan, or XKO-8044 polyolefin membranes commercially available from 3M Company, Minneapolis, Minn., U.S. A.

In accordance with the present disclosure, it has been found that the quality of the printed image on the absorbent article can be maintained at a print speed of about 500 feet per minute or more, and speeds of up to about 2000 feet per minute or more can be achieved without a separate drying step. By achieving such fast printing speeds without a drying step, manufacturing overhead costs will be reduced and user efficiency will be improved.

Industry standards for aqueous ink technology require that the pigment be absorbed onto the substrate while the water is removed by evaporation in a drying oven. In order to adequately dry these aqueous inks at current processing speeds, the drying oven must be at least 40 feet or more. Most production lines do not have sufficient space to accommodate these types of large drying ovens and are not economically feasible. Moreover, even if these lines could be modified to accommodate these large drying ovens, their operating costs and potential impact on print quality would be risky and too costly to justify the expense required to implement such lines. Therefore, a solution is needed that does not require these large drying ovens.

Surprisingly and unexpectedly, the present disclosure has found a solution to the foregoing. Instead of evaporating the liquid with a large drying oven, the solution for absorbing the pigments onto the substrate is to spread and absorb the liquid (such as water and pigments) onto the substrate with a thin ink receptive coating.

Ink-absorbing coating

The ink receptive coating needs to be thick enough to absorb the liquids, such as water, contained in the aqueous ink. An optimum thickness to achieve adequate removal of liquid by the coating is about 0.1 mm or less.

Suitable ink receptive coatings include, but are not limited to, absorbent materials such as talc, cellulosic fibers, superabsorbents, for example, to aid in absorption. The coating may also contain wetting agents, such as surfactants, to ensure a near zero contact angle when the ink is in contact with the coating. The coating may include other coatings and coatings to the substrate to improve dry and wet crockfastness.

Upon absorbing liquid, the basis weight of the ink-receptive coating disclosed herein is reduced, on average, from about 25% to about 35% from its original weight. The aqueous ink contains a pigment, wherein the coating absorbs a liquid, such as water, from the ink at a contact angle of zero degrees or about zero degrees, when the ink is printed onto a substrate at a print speed of at least about 500 feet per minute. It is important to note that the ink receptive coating must have a thickness, preferably about 0.0015mm, and a basis weight, preferably 3gsm, to increase the absorption and wetting rates of the coating. The absorption rate and wetting rate of the ink receptive coating are important measures of the present disclosure. Thus, the rate of removal of liquid from the ink on the ink receptive coating may be 10 seconds or less. Or more preferably 5 seconds or less. Or even more preferably 2 seconds or less. Or most preferably 1 second or less. More specifically, during the manufacturing process, a liquefied pigmented ink is applied to the coating whereby a liquid such as water is absorbed by the coating and the ink can then be absorbed onto the substrate, thereby eliminating the need for dry equipment.

Aqueous ink composition

Embodiments of the present invention include ink compositions comprising water-based inks. The ink composition may comprise a water-based polymer, a binder component, a redissolving agent, a pigment, and optionally a wax and/or a lubricant. Examples of water-based Inks useful in the present disclosure are available from Environmental Inks and Coatings Corporation, Morganton, n.c. under the following codes: EH034677 (yellow); EH057960 (magenta); EH028676 (cyan); EH092391 (black); EH034676 (orange); and EH064447 (green) and any similar inks thereof. Other suitable coatings are inkjet coatings such as nucoatdigital 9191MIJ or Lubrizol DP 338.

The aqueous ink composition may comprise a polymer such as acrylic, acrylic latex, styrenated acrylic, ethylene vinyl acetate, ethylene vinyl chloride, and Styrene Butadiene Rubber (SBR), or any combination thereof.

The aqueous ink composition may comprise a binder component. The binder component may be about 20 wt% to about 45 wt% of the ink composition. In one embodiment of the present invention, the binder component may be a polyurethane dispersion (also referred to herein as "PUD"). The PUDs may be high elongation, high tensile strength, high hardness, water-based polymer dispersions.

The aqueous ink may comprise a wax component. The wax component may be about 8 wt% to about 18 wt% of the aqueous ink composition. Waxes or wax blends may be used in the present invention. Suitable waxes/blends include polyethylene, carnauba wax, paraffin wax, silicone oil, polypropylene, polyolefin blends, and combinations thereof.

The aqueous ink may comprise a redissolving agent. The redissolving agent can be about 5.0 wt% to about 16.0 wt% of the ink composition. Resolubilizers useful in the present invention include acrylic solutions and dispersions having high to moderate carboxyl functionality. In one embodiment, a medium acid number acrylic colloidal dispersion redissolution agent can be used in the present disclosure.

The aqueous ink composition may contain additional waxes and lubricants for detackification and CoF reduction. The additional wax/lubricant blend may consist of palm wax (wax) and silicone oil (lubricant). In one embodiment, the wax/lubricant blend is about 1% to about 4% by weight of the composition. Waxes useful in the present invention include polyethylene, polypropylene, high density polyethylene, low density polyethylene, and paraffin waxes.

Pigmented aqueous ink composition and printing technique

The aqueous ink may comprise a pigment. Examples of suitable pigments include, but are not limited to, blue 15:3, violet 23, violet 27, yellow 14, yellow 74, yellow 83, yellow 97, yellow 13, green 7, red 2, red 22, red 48:1, red 57:1, red 122, red 184, red 238, red 269, red 49:1, red 81:1, red 49:2, red 166, red 170, orange 5, orange 16, orange 46, white 7, black 7, iron oxide, and combinations thereof. In one embodiment, from about 10% to about 16% by weight of pigment is used, but this may vary depending on the particular color and desired density. In one embodiment, pigments in colloidal dispersion (collectively referred to as colorants) may be used in the present disclosure.

Printing of substrates such as woven and nonwoven fabrics and films is well known. Printing fabrics with inks and dyes is a popular and widely used method for imparting patterns and colors to base fabrics. Many current products, such as diapers and training pants, include printed graphics to improve their appearance. A problem with such printed products is that the printed graphics may be soiled or even removed during handling of the product, during manufacture, packaging and use.

Pigmented inks are beneficial for use on substrates because they tend to be more resistant to leaching and mechanical abrasion than dye-based inks and therefore tend to be more resistant to removal from the substrate surface. Pigment-based inks also have better optical density per unit weight (better "mileage") than dye-based inks, which means that less pigment-based ink is needed to produce the intensity of the color. However, the binder component must be used with the pigmented ink to prevent the pigment from being removed from the surface by mechanical abrasion or chemical leaching.

In recent years, pigment-based inks have been increasing in industrial importance. This is driven in part by the development of many new synthetic substrates that cannot be printed using conventional solvent-based or water-based inks and by consumer preferences in their goods being printed with brand identifiers, aesthetically pleasing patterns, or functional indicia. To make pigment-based inks suitable for a variety of applications, i.e., low surface tension substrates, others have employed high loadings of volatile organic compounds ("VOC's") to reduce the static and dynamic surface tension of the ink. However, volatile organic compounds such as alcohols, esters, ketones, aromatic compounds and aliphatic compounds can create environmental hazards in their production, disposal and use. They are also expensive. One example of an ink for use on a low surface tension substrate is described in U.S. Pat. No. 5,458,590 to Schleinz et al, which is incorporated herein by reference, which employs a solvent blend to impart the desired surface tension to the ink.

The aqueous ink composition may comprise a surfactant. The surfactant may be present in a range of about 1.0% to about 10.0% by weight of the ink composition. Surfactants useful in the present invention include dioctyl sulfosuccinate, phosphate esters, alkoxylated alcohols, ethoxylated glycols, and mixtures or blends thereof.

The aqueous ink composition may be applied to the substrate using an ink jet printer, a flexographic printer, a gravure printer, or a combination thereof. The aqueous ink composition may be printed on different portions of the absorbent article components, including but not limited to the front waist region, the back waist region, the crotch region interconnecting the front waist region and the back waist region, and may extend from the side panels of the absorbent article to the outer surface of the cuffs or flaps.

As previously mentioned, the substrates disclosed herein are preferably very hydrophobic, such as untreated polyethylene and polypropylene. The substrate may also be treated with other ingredients to improve the adhesion of the coating to the substrate. Corona treatment of a substrate to improve adhesion of the coating to the substrate is also used herein to improve adhesion of the coating to the substrate. The corona treatment must be carried out at an optimum time. If the corona treatment time is too long, the properties of the coating and the substrate surface will be deteriorated. For the purposes of the present disclosure, other suitable printing methods may be used, such as digital inkjet printing.

In one embodiment, the aqueous ink composition is applied to the substrate by flexographic or rotogravure printing. In another embodiment of the present disclosure, the pattern or graphic printed onto the absorbent article is accomplished by sparse printing on the absorbent article of the printed package. Sparse printing is defined as a low basis weight ink where the porosity is small enough to limit spreading of the ink and/or liquid on an ink receptive coating such as a plastic film or a micro or non-porous nonwoven. By printing on such a surface, a smoother image/graphic and/or pattern will be provided on the final printed absorbent article.

Other printing embodiments of the present disclosure involve the use of a metering roller or doctor blade system. The metering roll is a pitted metal roll used to transfer a metered ink film from an ink fountain to the surface of a flexographic printing plate. A doctor blade system is a mechanical device used to remove excess ink from a print cylinder. It allows some ink to settle on the drum as it removes some ink, thereby metering the amount of ink leaving the drum.