KR20170123947A - Uv-curable ink composition - Google Patents

Abstract

The present invention relates to a UV-curable ink composition which comprises a reactive acrylic resin, a reactive acrylate oligomer, a reactive acrylate monomer, a photopolymerization initiator, and a pigment, and which can be removed by a solvent such as alcohol and the like even after printing and curing; and relates to a printed article including a cured material of the composition.

Description

[0001] UV-CURABLE INK COMPOSITION [0002]

The present invention relates to an ultraviolet curable ink composition capable of being printed on a battery for power supply of an electronic product, a non-absorbing surface printing material and various printed materials, and which can be removed by a solvent even after photo-curing, and a printed article comprising the cured product.

Conventional solvent-based inks cause problems such as workability and working environment in printing the capacity, preparation method, and precautions indicated on the surfaces of batteries, household appliances, containers, and the like. In order to solve such a problem, when a photocurable ink is introduced, adhesiveness, abrasion resistance, and printing workability can be improved. Therefore, the photocurable ink is applied variously to a battery, a non-absorbent material or various containers and prints using the same to supply electric power to home appliances such as cellular phones, digital cameras, and notebooks.

UV curable inks typically include photoinitiators, reactive monomers or oligomers, pigments, and other additives. However, conventional photocurable inks using a reactive acrylate monomer and an oligomer as a photopolymerization reaction composition have a characteristic that they can not be erased once they are cured, making it impossible to reuse a product to be printed when a printing appearance defect occurs during printing, This leads to product defects and needs to be improved.

Korean Patent Publication No. 2000-0069460 Korean Patent Publication No. 2002-0000751

It is an object of the present invention to provide an ultraviolet curable ink composition which can be removed by a solvent or the like even after being cured in a printed state and a printed article containing the cured product .

The above-described object of the present invention is achieved by an ultraviolet (UV) curable ink composition comprising a reactive acrylic resin.

Accordingly, the present invention relates to an ultraviolet curable ink composition comprising a reactive acrylic resin, a reactive acrylate oligomer, a reactive acrylate monomer, a photopolymerization initiator, and a pigment.

In one embodiment of the present invention, the reactive acrylic resin includes an acrylic copolymer having repeating units derived from at least one monomer selected from among aliphatic alkyl (meth) acrylates having 1 to 6 carbon atoms.

In one embodiment of the present invention, the reactive acrylic resin is an acrylic resin having repeating units derived from a monomer selected from the group consisting of methyl (meth) acrylate, ethyl (meth) acrylate and butyl (meth) ≪ / RTI >

In one embodiment of the present invention, the acrylic copolymer may further include a repeating unit derived from (meth) acrylic acid.

In one embodiment of the present invention, the UV curable ink composition contains a reactive acrylic resin in an amount of 25 to 30 wt%, preferably 27 to 29 wt%.

In one embodiment of the present invention, the UV curable ink composition comprises 30 to 40% by weight of a reactive acrylate oligomer, 5 to 10% by weight of a reactive acrylate monomer, 8 to 10% by weight of a pigment, and 5 to 10% .

In one embodiment of the present invention, the reactive acrylate oligomer is at least one selected from the group consisting of epoxy acrylate, urethane acrylate and polyester acrylate.

In one embodiment of the present invention, the reactive acrylate monomer is at least one selected from the group consisting of 1,6-hexanediol diacrylate (HDDA) and tetrahydrofurfuryl acrylate (THFA).

In one embodiment of the present invention, the photopolymerization initiator is at least one selected from the group consisting of a phosphine oxide-based photoinitiator, a thioxanthone-based photoinitiator, and an alkylarylketone-based photoinitiator.

In one embodiment of the present invention, the photopolymerization initiator is selected from the group consisting of diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide (TPO), 2-isopropylthioxanthone (ITX) Methyl-1- [4- (methylthio) phenyl] -2- (4-morpholinyl) - 2-methyl- 1-propanol, and 1-propanol.

The present invention also relates to a printed article comprising a cured product of the ultraviolet curable ink composition described above.

In one embodiment of the present invention, the printed article may include a battery, a nonabsorbent material, or a container or print using a nonabsorbent material.

According to the present invention, there is provided an ultraviolet curable ink composition which can be printed on a battery for power supply of an electronic product, a non-absorbent cotton printing material and various printed materials, and which is removable by a solvent.

The ultraviolet curable ink composition according to the present invention has excellent printability, adhesiveness and abrasion resistance, and it has been confirmed that it can be removed by using a solvent such as alcohol after printed and photocured by the inclusion of a reactive acrylic resin.

The ultraviolet curable ink composition according to the present invention has excellent printability and reliability and can be dissolved and removed in a solvent even after being cured. Therefore, in a printing process for a battery of an electronic product, a non- It is possible to reuse the product even in the event of occurrence, and it is possible to achieve the effects of reduction in defects, reduction in manufacturing cost, improvement in quality, and improvement in productivity.

Fig. 1 is a photograph showing that a conventional UV curable ink composition is printed and UV-cured and then cleared by alcohol.
Fig. 2 is a photograph showing that the printed portion is erased when it is printed with UV curable ink composition according to the present invention and is cured by UV after UV curing.

The present invention relates to an ultraviolet (UV) curable ink composition comprising a reactive acrylic resin. In the present invention, by incorporating the reactive acrylic resin in the ultraviolet curable ink composition, unlike the conventional acrylate ultraviolet curable ink composition, even after the photo curing, a solvent such as methanol, ethanol, isopropyl alcohol (IPA) So that it can be removed by a solvent.

In one embodiment of the present invention, the reactive acrylic resin includes an acrylic copolymer having a repeating unit derived from a monomer selected from among aliphatic alkyl (meth) acrylates having 1 to 6 carbon atoms.

In one embodiment of the present invention, the reactive acrylic resin comprises a repeating unit derived from at least one monomer selected from the group consisting of methyl (meth) acrylate, ethyl (meth) acrylate and butyl (meth) ≪ / RTI >

In one embodiment of the present invention, the acrylic copolymer may further include a repeating unit derived from (meth) acrylic acid.

In the present invention, the above-mentioned reactive acrylic resin is selected from the base sheet International ELVACITE ^® series of acrylic resins (Lucite International), specifically, the group consisting of ^{ELVACITE ® 2010, 2021E, 3001,} 3007, 3008, 2009, 3010 and 4045 ≪ / RTI >

The ultraviolet curable ink composition of the present invention preferably contains 25 to 30% by weight, more preferably 27 to 29% by weight, of the reactive acrylic resin based on the total weight of the composition. The physical properties of the photocurable ink composition depend on the content of the reactive acrylic resin. If the content of the reactive acrylic resin exceeds 30% by weight, the ink properties such as viscosity, printability, and curability of the ink composition and the abrasion resistance of the printed article are lowered. If the content is less than 25% by weight, It can not be removed. In the present invention, by adding a reactive acrylic resin to the UV curable ink composition, the solvent can be removed even after curing, while maintaining properties such as adhesion, abrasion resistance and printability.

The photocurable ink composition of the present invention further includes a reactive acrylate oligomer, a reactive acrylate monomer, a pigment, and a photopolymerization initiator, which are used in a conventional photocurable ink composition, in addition to the above-mentioned reactive acrylic resin.

The reactive acrylate oligomer is at least one selected from the group consisting of epoxy acrylate, urethane acrylate and polyester acrylate. The acrylate monomers are monomers having at least one acrylic functional group, such as monofunctional acrylates such as tetrahydrofurfuryl acrylate (THFA), 1,6-hexanediol diacrylate (HDDA) Bifunctional acrylate, and the like, but are not limited thereto.

The reactive acrylate oligomer and the reactive acrylate monomer are preferably contained in an amount of 30 to 40 wt% and 5 to 10 wt%, based on the total weight of the photocurable ink composition.

The photopolymerization initiator generates an active radical when ultraviolet rays of a specific wavelength range are irradiated, and the generated radical induces a photopolymerization reaction of the reactive acrylate oligomer or monomer. The photopolymerization initiator is at least one selected from the group consisting of a phosphine oxide-based photoinitiator, a thioxanthone-based photoinitiator, and an alkylarylketone-based photoinitiator. Specific examples of the photopolymerization initiator include diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide (TPO), 2-isopropylthioxanthone (ITX), 1 -hydroxy-cyclohexyl- Methyl-1- [4- (methylthio) phenyl] -2- (4-morpholinyl) -1-propanone, But is not limited thereto.

The photopolymerization initiator is suitably used in an amount of 5 to 10% by weight based on the total weight of the photocurable ink composition. When the content is less than 5% by weight, the curing rate is low and problems such as uncured or scratch may occur. When the content exceeds 10% by weight, the radical concentration excessively increases, unreacted material increases, , And the hardness of the ink is weakened. In the present invention, the aforementioned photopolymerization initiators are used in combination of one or more, preferably two or more. When two or more kinds of photopolymerization initiators are used, the reactivity of the curing reaction can be improved, and as the reactivity is improved, the improvement of the curing performance of the printing surface, such as the improvement of the drying speed of the printed matter, may be achieved. Any of pigments known in the ink field such as black, white, blue, yellow and red pigments can be used without limitation, and the pigment is usually used in a range of 8 to 10% by weight based on the total weight of the ink composition.

 The photocurable ink composition of the present invention may further include conventional additives well known in the field of UV curable inks used for ensuring the physical properties of the UV curable ink composition, for example, leveling agents, antifoaming agents and the like. These additives maximize the pore-forming property and the leveling property of the ink composition, thereby improving the printing appearance and contributing to the improvement of the abrasion resistance. The leveling agent may comprise a reactive silicone acrylate of polyester modified polydimethylsiloxane series. Further, the ultraviolet curable ink composition of the present invention may further include other additives well known in the ink composition art. The additive may be selected from the group consisting of a filler that adjusts the viscosity of the ink composition and adjusts the viscosity of the ink composition by imparting irregularity, a component for protecting and protecting the slip property of the printing surface, Anti-foaming agents, stabilizers that improve the shelf life of the product, and the like.

The printing method of the photocurable ink composition according to the present invention is not limited. For example, it may be printed by a method such as screen printing, offset printing, flexo printing, letter press printing, pad (PAD) printing, etc., Or may be printed in a stacking manner. Is printed with a thickness of 8 to 10 mu m, and is cured using an ultraviolet curing apparatus. When printed at an ultraviolet irradiation amount (light amount) of 400 to 500 mj / cm 2, printed matter excellent in adhesiveness, abrasion resistance, removability, and printing appearance can be obtained. The light source for ultraviolet curing is not particularly limited as long as it can irradiate a wavelength in the ultraviolet region, such as an ultraviolet lamp or an LED light source.

Example

Hereinafter, preferred embodiments of the flexible dye-sensitized solar cell according to the present invention will be described in detail with reference to the accompanying drawings.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It is to be understood, however, that the embodiments are not intended to limit the invention to the specific embodiments, but include all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting of the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. It is to be understood that the terms " including, "" having ", "having ", and the like are intended to indicate that there are features, numbers, steps, operations, elements, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, parts, or combinations thereof.

Example 1

Epoxy acrylate oligomer (product name: EB 605, manufacturer: SK Cy Tech) 15g, a polyester acrylate oligomer (product name: EB 812, manufacturer: SK Cy Tech) 21g, a reactive acrylic resin (product name: ELVACITE ^® 3010, Manufacturer: Lucite Internationally, 28 g of a reactive monomer, 7 g of a photopolymerization initiator, 8 g of a photopolymerization initiator, 1 g of ITX, 1 g of 2-methyl-1- [4- (methylthio) phenyl] -2- IRGACURE ^® 907) 1g, pigment (BASF Corp.) 9.5g, anti-foaming agent (product name: N-Formax, Manufacturer: TEGO) 5g, wax (Deutron 9815, manufacturer: Deutron) 1g, silica (product name: Aerosil-200, manufacturer: BYK) and 1 g of a leveling agent (trade name: BYK 3510, manufacturer: BYK) were mixed and stirred at room temperature for 30 minutes and then dispersed three times with 3 rolls to adjust the particle size to 5 탆 or less, A composition was prepared.

Ink compositions of Examples and Comparative Examples having the compositions shown in the following Table 1 were prepared by the method described in Example 1.

ingredient Example Comparative Example One 2 3 4 5 6 7 One 2 Reactivity
acryl
Suzy ELVACITE ^® 3010 28 28 26 24 30 32 20 - -
Olly
Gomer Polyester
Acrylate (EB 812) 21 15 22 22 15 15 21 22 49 Epoxy acrylate (EB 605) 15 21 16 18 23 14 15 Urethane acrylate (EB 284) - - - - 17 19 - 28 - Monomer THFA 7 7 7 7 7 7 7 7 7  Pigment 9.5 9.5 9.5 9.5 9.5 9.5 9.5 9.5 9.5 Initiator TPO 8 8 8 8 8 8 8 8 8 ITX One One One One One One One One One IRGACURE 907 One One One One One One One One One additive Silica (Aerosil-200) 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 Wax (Deutron 9815) One One One One One One One One One Leveling agent (BYK 3510) One One One One One One One One One Defoamer (Formax-N) 5 5 5 5 5 5 5 5 5 Stabilizer (UV-1) One One One One One One One One One Total (% by weight) 100 100 100 100 100 100 100 100 100

Property evaluation and analysis

The UV curable ink compositions having the compositions shown in Table 1 were evaluated by the methods described below, and the results are shown in Table 2.

Viscosity: The viscosity of the ink composition was measured at 30 rpm at room temperature (25 캜) using a Brookfield B-type viscometer.

Adhesiveness: The ink composition was printed by a pad printing method, photocured at a light quantity of 350 mj / cm < 2 > or more by using a metal lamp, 11 lines of 1 mm in width and 1 mm length were drawn with a knife at room temperature, A tape (SCOTCH 810, manufactured by 3M Company) was rubbed five times with 500 g of acupressure and then peeled off in a direction perpendicular to the surface. The degree to which the coating film was not peeled was taken as 100, and the degree of peeling was expressed as a relative value.

Abrasion resistance: The number of times the printed portion was cleared when a 500 g load was applied to the printed portion by reciprocating the printed portion was recorded in an abrasion resistance evaluation tester (CK Esey product, Lab-QE eraser abrasion test). When the number of reciprocations is 30 or more, it is evaluated that the abrasion resistance standard is satisfied.

Removability: Ethanol was applied to the cotton pad to wipe off the printed area.

Printing Appearance: Characters of the printed specimen and print contamination were visually observed.

Evaluation items Example Comparative Example One 2 3 4 5 6 7 One 2 Viscosity (cps) 3800 4500 3850 3800 3800 3600 3600 4200 4300 Adhesiveness 100/100 40/100 70/100 60/100 100/100 80/100 80/100 50/100 40/100 Abrasion resistance (times) 50 100 50 50 50 60 60 80 70 Removability Good Good Good Bad Good Bad Bad Bad Bad Print appearance Good Good Good Good Good Good Good Good Good

As shown in Table 2, the UV curable ink composition according to the embodiment of the present invention is excellent in viscosity, adhesion, abrasion resistance, and print appearance suitable for printing, and can be removed by a solvent such as alcohol even after printing and curing Respectively.

The present invention has been described by way of examples. It will be understood by those skilled in the art that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. It is therefore to be understood that the above-described embodiments are to be considered in all respects as illustrative and not restrictive. The scope of the present invention is defined by the appended claims rather than the detailed description and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of the present invention.

Claims (11)

Reactive acrylic resin, reactive acrylate oligomer, reactive acrylate monomer, photopolymerization initiator, and pigment. The method according to claim 1,
Wherein the reactive acrylic resin comprises an acrylic copolymer having a repeating unit derived from a monomer selected from aliphatic alkyl (meth) acrylates having 1 to 6 carbon atoms. 3. The method of claim 2,
Wherein the reactive acrylic resin comprises an acrylic copolymer having a repeating unit derived from at least one monomer selected from the group consisting of methyl (meth) acrylate, ethyl (meth) acrylate and butyl (meth) UV curable ink composition. The method of claim 3,
Wherein the acrylic copolymer further comprises a repeating unit derived from (meth) acrylic acid. The method according to claim 1,
Wherein the reactive acrylate oligomer is contained in an amount of 25 to 30% by weight, the reactive acrylate oligomer is 30 to 40% by weight, the reactive acrylate monomer is 5 to 10% by weight, the pigment is 8 to 10% by weight and the photopolymerization initiator is 5 to 10% Ink composition. The method according to claim 1,
Wherein the reactive acrylate oligomer is at least one selected from the group consisting of epoxy acrylate, urethane acrylate and polyester acrylate. The method according to claim 1,
Wherein the reactive acrylate monomer is at least one selected from the group consisting of 1,6-hexanediol diacrylate and tetrahydrofurfuryl acrylate. The method according to claim 1,
Wherein the photopolymerization initiator is at least one selected from the group consisting of a phosphine oxide-based photoinitiator, a thioxanthone-based photoinitiator, and an alkylarylketone-based photoinitiator. 9. The method of claim 8,
The photopolymerization initiator may be at least one selected from the group consisting of diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide, 2-isopropylthioxanthone, 1 -hydroxy-cyclohexyl- 1-propanone and 2-methyl-1- [4- (methylthio) phenyl] -2- (4-morpholinyl) Curable ink composition. A printed article comprising a cured product of the ultraviolet-curable ink composition according to any one of claims 1 to 9. 11. The method of claim 10,
Batteries, non-absorbent materials, or printed materials that are containers or printed materials using non-absorbent materials.

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