阅读说明：本技术 印刷uv墨水及其制备方法、应用 (Printing UV ink and preparation method and application thereof ) 是由 时文强 周炜城 于 2020-12-31 设计创作，主要内容包括：本发明提供一种印刷UV墨水及其制备方法、应用,其中印刷UV墨水包括颜料色浆、第一单体、第二单体、低聚物、光引发剂和助剂,其中第一单体为烷氧基改性丙烯酸酯或聚乙二醇类丙烯酸酯中的至少一种,第二单体为烷氧基改性三官丙烯酸酯；低聚物的分子量为1500～6000,低聚物的黏度小于等于13000cps；颜料色浆包括颜料、分散剂和第一单体；采用以上方案,使得墨水中的单体的分子量增大,其挥发性降低,使得气味相对应地降低；且改性后的丙烯酸酯单体的结构中含有柔性烷氧链段,提高墨水打印后的柔韧性,可避免打印后的墨层弯折后开裂。(The invention provides printing UV ink and a preparation method and application thereof, wherein the printing UV ink comprises pigment color paste, a first monomer, a second monomer, an oligomer, a photoinitiator and an auxiliary agent, wherein the first monomer is at least one of alkoxy modified acrylate or polyethylene glycol acrylate, and the second monomer is alkoxy modified trifunctional acrylate; the molecular weight of the oligomer is 1500-6000, and the viscosity of the oligomer is not more than 13000 cps; the pigment color paste comprises a pigment, a dispersing agent and a first monomer; by adopting the scheme, the molecular weight of the monomer in the ink is increased, the volatility of the monomer is reduced, and the odor is correspondingly reduced; and the structure of the modified acrylate monomer contains a flexible alkoxy chain segment, so that the flexibility of the ink after printing is improved, and the printed ink layer can be prevented from cracking after being bent.)

1. Printing UV ink, characterized in that: the color paste comprises pigment color paste, a first monomer, a second monomer, an oligomer, a photoinitiator and an auxiliary agent, wherein the molecular weight of the oligomer is 1500-6000, and the viscosity of the oligomer is less than or equal to 13000 cps; the first monomer is at least one of alkoxy modified acrylate or polyethylene glycol acrylate; the second monomer is alkoxy modified trifunctional acrylate; the pigment color paste comprises a pigment, a dispersing agent and the first monomer.

2. The printed UV ink of claim 1, wherein:

the sum of the number of the alkoxy groups in the second monomer and the first monomer is 2 to 15.

3. The printed UV ink of claim 1, wherein:

according to the mass percentage, the ink comprises 5 to 15 percent of the pigment color paste, 55 to 75 percent of the first monomer, 1 to 5 percent of the second monomer, 1 to 15 percent of the oligomer, 6 to 10 percent of the photoinitiator and 0.1 to 1 percent of the auxiliary agent;

the pigment color paste comprises 18-22% of the pigment, 5-15% of the dispersant and 65-75% of the first monomer by mass percent.

4. The printed UV ink of claim 1, wherein:

the alkoxy modified acrylate is at least one of ethoxylated tetrahydrofurfuryl acrylate, ethoxylated 1, 6-hexanediol acrylate, propoxylated neopentyl glycol acrylate, propoxylated trimethylolpropane acrylate, ethoxylated trimethylolpropane acrylate, methoxylated polyethylene glycol monoacrylate or ethoxylated polyethylene glycol monoacrylate, the methoxylated polyethylene glycol monoacrylate can be methoxylated polyethylene glycol monoacrylate with the polymerization degree of 350, and the ethoxylated polyethylene glycol monoacrylate can be ethoxylated polyethylene glycol monoacrylate with the polymerization degree of 550.

5. The printed UV ink of claim 1, wherein:

the polyvinyl alcohol acrylate is polyethylene glycol diacrylate, and the polyethylene glycol diacrylate can be polyethylene glycol diacrylate with the polymerization degree of 400 and/or 200.

6. The printed UV ink of claim 1, wherein:

the alkoxy modified trifunctional acrylate is at least one of propoxylated trimethylolpropane triacrylate and propoxylated trimethylolpropane triacrylate.

7. The printed UV ink of claim 1, wherein:

the photoinitiator is a hydrogen abstraction photoinitiator.

8. The printing UV ink according to any one of claims 1 to 7, characterized in that:

the viscosity of the ink at 25 ℃ is 7.0cps to 30cps, and the surface tension is 20mN/m to 30 mN/m.

9. Printing UV ink preparation method for preparing a printing UV ink according to any one of claims 1 to 8, characterized in that: the preparation method comprises the following steps:

s1, mixing the pigment, the dispersing agent and the first monomer in proportion, and adding the mixture into a sand mill to obtain pigment color paste;

s2, uniformly mixing the first monomer and the second monomer, adding the photoinitiator for complete dissolution, adding the oligomer and the auxiliary agent, and stirring for 1-2 hours to obtain a mixed solution;

and S3, adding the pigment color paste into the mixed solution in the S2, and filtering after dispersion treatment.

10. Use of a printing UV ink, characterized in that: the ink of any one of claims 1 to 8 for printing on packaging material.

Technical Field

The invention relates to the field of ink, in particular to printing UV ink and a preparation method and application thereof.

Background

The packaging printing materials are various, including various materials such as cardboard paper, corrugated paper, PVC and PMMA, and water-based ink or solvent-based ink is mostly adopted to print in the materials in the market at present. However, the water-based ink has a slow drying speed, poor glossiness and a relatively dark printing color effect. The solvent-based ink can adapt to various printing materials, but the evaporation of the solvent in the ink can discharge harmful substances into the air, and the development trend of environmental protection is not met. The UV ink has applicability to various base materials, can provide bright and bright colors, has high drying speed, and can meet the strict requirements of packaging printed matters on color expression and curing speed. However, as the components in the UV ink volatilize small molecules which have certain irritation, the smell of the UV ink is relatively irritating and unpleasant, and the use of users is affected.

Disclosure of Invention

It is a first object of the present invention to provide a printed UV ink with reduced evaporation.

The second purpose of the invention is to provide a preparation method of the printing UV ink.

A third object of the present invention is to provide a use of the above-mentioned printing UV ink.

In order to achieve the first purpose, the printing UV ink provided by the invention comprises pigment color paste, a first monomer, a second monomer, an oligomer, a photoinitiator and an auxiliary agent according to mass percentage, wherein the molecular weight of the oligomer is 1500-6000, the viscosity of the oligomer is less than or equal to 13000cps, the first monomer is at least one of alkoxy modified acrylate or polyethylene glycol acrylate, and the second monomer is alkoxy modified trifunctional acrylate; the pigment color paste comprises a pigment, a dispersing agent and a first monomer.

According to the scheme, the first monomer and the second monomer used in the ink are both modified acrylate, so that the molecular weight of the monomers in the ink is increased, the volatility of the monomers is reduced, and the odor is correspondingly reduced; the structure of the acrylate monomer modified by alkoxy contains a flexible alkoxy chain segment, so that the flexibility of the ink after printing is improved, the printed ink layer can be prevented from cracking after being bent, and the acrylate monomer has good adhesion to paper, plastic, metal and other substrates, so that the ink layer has certain mechanical strength and bending resistance and good adhesion; the second monomer and the first monomer exist in the ink at the same time, so that the photocuring degree of the ink can be improved, and the phenomenon that the ink layer is incompletely cured to cause hand sticking is avoided; and because the alpha-H on the ether structure-O-CH 2-in the alkoxy group is easily substituted by oxygen, on one hand, partial oxygen in the ink can be consumed, on the other hand, peroxide free radicals ROO generated by free radicals and oxygen can be generated, the consumption of active free radicals is reduced, and the initiating activity is transferred to a chain segment with the initiating activity again, so that the polymerization resistance of oxygen to the photocuring process is reduced, and the curing degree of a curing system is improved.

In a further embodiment, the sum of the number of alkoxy groups in the second monomer and the first monomer is 2 to 15.

It can be seen that the molecular weights of the second monomer and the first monomer are controlled by controlling the number of alkoxy groups in the monomers in the ink, so that the ink odor is reduced and the viscosity of the ink is prevented from increasing.

The further proposal is that the ink comprises 5 to 15 percent of pigment color paste, 55 to 75 percent of first monomer, 1 to 5 percent of second monomer, 1 to 15 percent of oligomer, 6 to 10 percent of photoinitiator and 0.1 to 1 percent of auxiliary agent according to the mass percentage; the pigment color paste comprises 18 to 22 percent of pigment, 5 to 15 percent of dispersant and 65 to 75 percent of first monomer according to the mass percentage.

The further scheme is that the alkoxy modified acrylate is at least one of ethoxylated tetrahydrofurfuryl acrylate, ethoxylated 1, 6-hexanediol acrylate, propoxylated neopentyl glycol acrylate, propoxylated trimethylolpropane acrylate, ethoxylated trimethylolpropane acrylate, methoxylated polyethylene glycol monoacrylate or ethoxylated polyethylene glycol monoacrylate, the methoxylated polyethylene glycol monoacrylate can be a methoxylated polyethylene glycol monoacrylate with a polymerization degree of 350, and the ethoxylated polyethylene glycol monoacrylate can be an ethoxylated polyethylene glycol monoacrylate with a polymerization degree of 550.

In a further embodiment, the polyvinyl alcohol acrylate is polyethylene glycol diacrylate, and the polyethylene glycol diacrylate may be polyethylene glycol diacrylate with a degree of polymerization of 400 and/or 200.

In a further embodiment, the alkoxy-modified trifunctional acrylate is at least one of propoxylated trimethylolpropane triacrylate and propoxylated trimethylolpropane triacrylate.

In a further embodiment, the photoinitiator is a hydrogen abstraction photoinitiator.

It can be seen that the alkoxy group can release hydrogen during curing, and in the process of being used in combination with the hydrogen abstraction type photoinitiator, the initiation efficiency of the photoinitiator can be improved, thereby improving the photocuring speed of the curing system.

Further, the viscosity of the ink at 25 ℃ is 7.0 to 30cps, and the surface tension is 20 to 30 mN/m. Preferably, the ink has a viscosity of 14 to 24cps at 25 ℃ and a surface tension of 21 to 25 mN/m.

It can be seen that the inks printed on the substrate in this viscosity range and surface tension range at 25 c cure rapidly and have good adhesion.

In order to achieve the second object, the present invention provides a method for preparing printing UV ink, which is used for preparing the printing UV ink, and comprises the following steps:

s1, mixing the pigment, the dispersing agent and the first monomer in proportion, and adding the mixture into a sand mill to obtain pigment color paste;

s2, uniformly mixing the first monomer and the second monomer, adding the photoinitiator for complete dissolution, adding the oligomer and the auxiliary agent, and stirring for 1-2 hours to obtain a mixed solution;

and S3, adding the pigment color paste into the mixed solution in the S2, and filtering after dispersion treatment.

Therefore, in the process of preparing the ink, the first monomer is divided into two parts, and firstly, in the process of preparing the pigment color paste, the first monomer is used as a grinding medium, and the pigment is ground to a nanometer level, so that the pigment can be applied to ink printing; and continuously mixing the oligomer and the auxiliary agent after the first monomer, the second monomer and the photoinitiator are completely dissolved, so that the photoinitiation effect is better, then adding the pigment color paste, and processing to obtain the UV ink.

In order to achieve the second object, the invention provides a method for printing UV ink on a packaging material.

Detailed Description

The printing UV ink is applied to a packaging material, the packaging material can comprise packaging paper, a packaging box and the like, and the packaging material can be made of PVC, PET, PMMA, corrugated paper and the like. The UV ink comprises 5 to 15 percent of pigment color paste, 55 to 75 percent of first monomer, 1 to 5 percent of second monomer, 1 to 15 percent of oligomer, 6 to 10 percent of photoinitiator and 0.1 to 1 percent of auxiliary agent, wherein the pigment color paste comprises 18 to 22 percent of pigment, 5 to 15 percent of dispersant and 65 to 75 percent of first monomer, wherein the second monomer and the first monomer are respectively alkoxy-modified acrylate and derivatives thereof, after the modification, the molecular weight of the second monomer and the first monomer is increased, so that the volatility is reduced, so that the odor of the ink is correspondingly reduced, and the first monomer modified by the alkoxy can improve the flexibility of the ink, and the second monomer exists simultaneously, so that the photocuring degree of the ink can be improved, and the printed ink layer has certain mechanical strength and bending resistance and good adhesion.

The printing UV ink comprises, by mass, 5-15% of pigment color paste, 55-75% of a first monomer, 1-5% of a second monomer, 1-15% of an oligomer, 6-10% of a photoinitiator and 0.1-1% of an auxiliary agent.

The pigment color paste comprises 18-22% of pigment, 5-15% of dispersant and 65-75% of first monomer by mass percent, and preferably comprises 20% of pigment, 10% of dispersant and 70% of first monomer. The dispersant can be Solsperse from Lubrizol^TM32000。

The first monomer is at least one of alkoxy modified acrylate or polyethylene glycol acrylate, wherein the alkoxy modified acrylate can be at least one of ethoxylated tetrahydrofurfuryl acrylate, ethoxylated 1, 6-hexanediol acrylate, propoxylated neopentyl glycol acrylate, propoxylated trimethylolpropane acrylate, ethoxylated trimethylolpropane acrylate, methoxylated polyethylene glycol monoacrylate and ethoxylated polyethylene glycol monoacrylate, and the methoxylated polyethylene glycol monoacrylate can be methoxylated polyethylene glycol monoacrylate with the degree of polymerization of 350; the ethoxylated polyethylene glycol monoacrylate is an ethoxylated polyethylene glycol monoacrylate with the polymerization degree of 550. Preferably, the alkoxy-modified acrylate in the first monomer can be alkoxy-modified mono-functional acrylate or alkoxy-modified bi-functional acrylate, that is, the number of the acrylate is one or two, and the number of the acrylate is controlled to enable the printed ink layer to have certain flexibility and avoid cracking of the ink layer. The polyethylene glycol acrylate may be polyethylene glycol diacrylate, wherein the polyethylene glycol diacrylate may be polyethylene glycol diacrylate having a degree of polymerization of 400 and/or 200. The first monomer in the pigment paste can also be DPGDA2(PO) (SR 9003 from Sartomer company)

The second monomer is alkoxy-modified tri-functional acrylate and is at least one of propoxylated trimethylolpropane triacrylate and propoxylated trimethylolpropane triacrylate, wherein tri-functionality refers to functionality, i.e., the number of acrylates. The sum of the alkoxy groups in the second monomer and the alkoxy groups of the first monomer is 2 to 15 to control the total molecular weight of the monomers in the ink.

The oligomer is a polymer with a molecular weight of 1500-6000 and a viscosity of 13000cps or less, and can be selected from one or more of CN9009, CN990 and CN991 of Sartomer company, Miramon PU2100 and Miramer PU2200 of MIWON company.

The photoinitiator is one or more of TPO, DETX, Omnirad 819, Esacure KTO 46 and Omnipol ASA. Preferably, the photoinitiator may be a hydrogen abstraction type photoinitiator, which may be DETX, Omnirad 819, Esacure KTO 46.

The auxiliary agent can be one or two of a surfactant and an inhibitor, and the surfactant can be at least one selected from Tegorad 2200N, Tegorad 2100 and Tegorad 2300 of Evonik company, BYK 377, BYK 3510, BYK 307 and BYK 330 of BYK company. The inhibitor may be at least one of Genorad 16, Genorad 18 and Genorad20 from Rahn AG, Irgastab UV10 and Irgastab UV22, Tinuvin 460 and CGS20 from Ciba specialty Chemicals, Floorsttab UV-1, Floorsttab UV-2, Floorsttab UV-5 and Floorsttab UV-8 from Kromache, Additol S100, Additol S110, Additol S120 and Additol S130 from Cytec.

The preparation method of the printing UV ink provided by the invention is used for preparing the printing UV ink, and comprises the following steps:

s1, mixing the pigment, the dispersing agent and the first monomer in proportion, adding the mixture into a sand mill, and grinding the mixture for 6 to 8 hours at the rotating speed of 800 to 1200rpm by using zirconium beads with the diameter of 0.3mm up to now to obtain pigment color paste;

s2, uniformly mixing the first monomer and the second monomer, adding the photoinitiator for complete dissolution, adding the oligomer and the auxiliary agent, and stirring for 1-2 hours to obtain a mixed solution;

and S3, adding the pigment color paste into the mixed liquid in the S2, dispersing for 1-2 h at the rotating speed of 400-600 rpm, and filtering by using a 1-micron filter element to obtain the UV ink.

The present invention will be better understood by further describing the present invention with reference to specific examples, and specific components and values thereof of each example and comparative example are shown in Table 1.

TABLE 1

The inks of the examples and comparative examples were subjected to performance tests including adhesion test, bending performance test, tack-back performance test and odor test.

The ink prepared above was jet printed on PVC, PET and PMMA materials using a tokyo texture G5 printer to make test coupons and tested as follows.

Test 1: adhesion test

A hundred-grid knife is used for marking 10mmx10mm grids (every 1mm) on a test sample sheet every 1mm, a 3M company 610 adhesive tape is used for tightly adhering the grid positions, the adhesive tape is quickly pulled away in a mode of inclining at an angle of 45 degrees, the peeling area is checked, the adhesive force grade is judged according to the adhesive force grade, the grade 5 is the worst, the grade 0 is the best, namely the peeling area is less than 5%, and the test result is shown in the following table 2.

TABLE 2

Note: and (3) adhesive force grade: level 0-the scribed edge is smooth, and no print drops at the scribed edge and the cross point; level 1-small patches of print drop off at the cross points of the scribe lines, and the total drop area is less than 5%; 2, small pieces of print fall off at the edge and the cross point of the scribing line, and the total fall-off area is between 5 and 15 percent; grade 3-pieces of print drop at the edge and the intersection of the scribing line, and the total drop area is between 15 and 35 percent; 4-in the scribed edge and the cross point, a piece of print falls off, and the total area of the fall off is between 35 and 65 percent; grade 5-there is a patch of print missing at the edge and intersection of the scribe, and the total area missing is greater than 65%.

And (3) testing 2: bending property test

And folding the PMMA test sample sheet in half, and folding the folded edge vertically into a zigzag shape, wherein the sample sheet is qualified if the film layer is not cracked or cracks are not generated after being bent, and the sample sheet is unqualified if the film layer is cracked or cracks are generated.

And (3) testing: return adhesion Performance test

The picture of the PMMA test sample is attached to the picture, the picture is attached to the material, the PMMA test sample is placed on a platform and is pressed by a weight of more than 1 kilogram for 24 hours, and whether the ink layer fades or not is checked, and the ink layer drops and transfers. Judging the adhesive force grade according to the surface falling condition, and classifying into 4 grades, 1 grade: the picture is unfolded without adhesion, the ink layer does not fall off after the picture is unfolded, and the color is not transferred completely; and 2, stage: the picture is separated and unfolded, sticky and sticky, can be separated only by tearing, has no color transfer after being unfolded, and is complete; and 3, level: the pictures are obviously stuck together after being unfolded, but the colors are slightly transferred to the corresponding binding surfaces after being unfolded, or slightly fall off, and the total falling area is less than 5 percent of the test area; 4, level: the pictures are unfolded and obviously adhered together, after being torn and separated, the color is transferred to the corresponding binding surface in a large area or falls off, and the total falling area is more than 5 percent of the test area.

And (4) testing: odor test

The ink of examples 1 to 4 was poured into a disposable cup with an ink volume of 50ml, left for 2min, and 12 judges were asked to rate and record the ink samples to be tested, respectively. According to the odor size, the odor is divided into 6 grades, and 1 is no odor; 2-slightly odorous; 3-tasted but not irritating; 4, pungent smell; 5 ═ strong pungent odor; 6-intolerable taste. The average value of the evaluation staff grading grade is taken as the final detection result, which is shown in table 3.

TABLE 3

In summary, the ink layers printed in examples 1 to 4 have good adhesion and high flexibility on the material, and have less peeling phenomenon and no cracking phenomenon. In the tack-back test, the examples 1 to 4 and comparative example 1 did not exhibit the tack phenomenon; since the second monomer is not present in comparative examples 2 and 3, the inks in comparative examples 2 and 3 were not completely cured after printing, resulting in the occurrence of a sticking phenomenon. In the odor test, different acrylate derivatives which are not modified by alkoxy groups are relatively used in comparative examples 1 to 3, the inks in comparative examples 1 to 3 all have strong pungent odor, and the monomers in examples 1 to 4 adopt the acrylate derivatives modified by alkoxy groups, so that the final ink has no odor.

Finally, it should be emphasized that the above-described preferred embodiments of the present invention are merely examples of implementations, rather than limitations, and that many variations and modifications of the invention are possible to those skilled in the art, without departing from the spirit and scope of the invention.