TW201303502A - Photo-curable inkjet ink, cured film with surface liquid repellency, microlens and method for forming the same, optical component and image display device - Google Patents

Abstract

The disclosure provides a photo-curable inkjet ink which has excellent wetting diffusion properties for substrates such as acrylic resin substrates, and can form a cured film with surface liquid repellency which has excellent adhesion properties to the substrates. The photo-curable inkjet ink includes an organic solvent (A), a bi- or lower-functional (meth)acrylate (B) having hydroxyl groups, an urethane (meth)acrylate (C), a surfactant (D) and a photopolymerization initiator (E), and a content of the solvent (A) is 40 wt% to 98 wt% relative to 100 wt% of the photo-curable inkjet ink.

Description

Photocurable inkjet ink

The present invention relates to a photocurable inkjet ink which can be preferably used for manufacturing an optical device such as an image display device. More specifically, the present invention relates to a photocurable inkjet ink suitable for the manufacture of optical components having microlenses used in a backlight unit.

The microlens formed on the light guide plate for an image display device has been formed by injection molding using a mold. The method is a method in which a mold is required each time an article is designed, and when manufacturing a small number of types of microlenses, it is very costly.

In recent years, as a manufacturing method which is inexpensive and has a high degree of freedom in design, a method of forming a microlens on the surface of a substrate by an inkjet method has been proposed. However, the microlens formed using the previous composition has a large variation in pattern size and pattern height. problem.

In order to improve this problem, it has been proposed to perform a liquid-repellent treatment on the surface of a substrate by an inkjet method. In the liquid-repellent treatment, a negative-type photosensitive composition capable of forming a surface liquid-repellent cured film can be used (for example, see JP-A-2008-209739).

[Previous Technical Literature]

[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2008-209739

However, the negative photosensitive composition described in Patent Document 1 has poor wettability and diffusibility to a substrate such as an acrylic resin substrate, and Further, the obtained cured film may have poor adhesion to the substrate.

The present invention has been made in view of the above problems, and an object of the invention is to provide a photocurable inkjet ink which is excellent in wettability and diffusibility to a substrate such as an acrylic resin substrate, and can form an adhesion to a substrate. Excellent surface liquid-repellent hardening film.

The present inventors have found that a photocurable spray is formed by containing a specific amount of an organic solvent, a specific (meth) acrylate, a (meth) acrylate urethane, a surfactant, and a photopolymerization initiator. The ink ink can solve the above problems, and the present invention has been completed.

That is, the present invention includes the following items.

[1] A photocurable inkjet ink comprising an organic solvent (A), a difunctional or lower (meth) acrylate (B) having a hydroxyl group, and a (meth)acrylic acid urethane (C), The surfactant (D) and the photopolymerization initiator (E) are contained in an amount of from 40% by weight to 98% by weight based on 100% by weight of the photocurable inkjet ink.

[2] The photo-curable inkjet ink according to [1], wherein the (meth) acrylate (B) is a compound selected from the group consisting of the following formula (1), glycerol mono(meth)acrylate At least one compound selected from the group consisting of glycerol di(meth)acrylate and 2-hydroxy-3-propenyl-methoxypropyl (meth)acrylate.

(In the formula (1), n R ^a are each independently an alkylene group having a ring structure of 2 to 12 carbon atoms, R ^b is an alkyl group having 1 to 6 carbon atoms or hydrogen, and n is 1~ An integer of 30).

[3] The photocurable inkjet ink according to [1] or [2] wherein the (meth) acrylate (B) is selected from the group consisting of 2-hydroxyethyl (meth) acrylate, (methyl) ) 2-hydroxypropyl acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, (meth) acrylate At least one compound selected from the group consisting of -4-hydroxybutyl ester and 1,4-cyclohexanedimethanol mono(meth)acrylate.

[4] The photocurable inkjet ink according to any one of [1] to [3] wherein the (meth)acrylic acid urethane (C) is represented by the following formula (2) Compound.

(In the formula (2), R ¹ , R ² and R ³ each independently represent a divalent organic group having 1 to 20 carbon atoms, and R ⁴ and R ⁵ are each independently hydrogen or an alkyl group having 1 to 6 carbon atoms; , m and n are each independently an integer of 1 to 3).

[5] The photocurable inkjet ink according to [4], wherein R ¹ and R ³ in the above formula (2) are each independently an alkylene group having a carbon number of 1 to 10, and R ² is selected from the group consisting of One divalent group in the group (a).

[6] The photocurable inkjet ink according to any one of [1] to [5] further comprising the above (meth) acrylate (B) and (meth) acrylate urethane ( (M) acrylate (F) other than C).

[7] The photocurable inkjet ink according to any one of [1] to [6] wherein the surfactant (D) is selected from the group consisting of a fluorine-based surfactant and an anthrone-based surfactant. At least one compound in the group.

[8] The photocurable inkjet ink according to any one of [1] to [7] wherein the surfactant (D) is a compound having at least one reactive group.

[9] The photocurable inkjet ink according to [8], wherein the reactive group of the above surfactant (D) is selected from the group consisting of (meth)acrylonitrile, epoxy group and oxetanyl group. At least 1 base in the group consisting.

[10] The photocurable inkjet ink according to any one of [1] to [9] wherein the solvent (A) is an organic solvent having a boiling point of from 100 ° C to 300 ° C.

[11] The photocurable inkjet ink according to any one of [1] to [10] wherein the solvent (A) is a compound having a hydroxyl group.

[12] The photocurable inkjet ink according to any one of [1] to [11] wherein the viscosity at 25 ° C is 1.0 mPa. s~30 mPa. s.

[13] A surface liquid-repellent hardening film obtained by curing the photocurable inkjet ink according to any one of [1] to [12].

[14] A microlens formed on the surface liquid-repellent cured film according to [13] by an inkjet method.

[15] A method of forming a microlens, comprising the step of forming a microlens on the surface liquid-repellent cured film according to [13] by an inkjet method.

[16] An optical component comprising the microlens of [14].

[17] An image display device comprising the optical component according to [16].

The photocurable inkjet ink of the present invention is excellent in wettability and diffusibility of a substrate such as an acrylic resin substrate. Therefore, the photocurable inkjet ink of the present invention is applied onto a substrate such as an acrylic resin substrate by an inkjet method and cured, whereby a surface liquid-repellent hardening having a film thickness of 1 μm or less can be easily formed. membrane.

In addition, since the surface liquid-repellent cured film obtained from the photocurable inkjet ink of the present invention can be made into a film (having a film thickness of 1 μm or less), the coloring is small and the surface liquid repellency is high. When the ink method forms a microlens on the cured film, a microlens having a large pattern height to a pattern diameter ratio can be easily formed, and an optical component such as a light guide plate can be easily manufactured.

Further, since the surface liquid-repellent cured film obtained from the photocurable inkjet ink of the present invention is excellent in adhesion to a substrate such as an acrylic resin substrate, it is possible to provide peeling from the substrate and reliability even after long-term use. Excellent surface liquid-repellent hardening film.

Therefore, the photocurable inkjet ink of the present invention is useful for producing a high quality image display device.

[1. Photocurable inkjet ink]

The photocurable inkjet ink of the present invention (hereinafter also referred to as "the ink of the present invention") includes an organic solvent (A), a difunctional or lower (meth) acrylate (B) having a hydroxyl group, and (meth)acrylic acid. a urethane (C), a surfactant (D), and a photopolymerization initiator (E), and the above content is contained in an amount of 40% by weight to 98% by weight based on 100% by weight of the photocurable inkjet ink. Solvent (A).

The ink of the present invention contains the above-mentioned specific amount of the organic solvent (A), a difunctional or lower (meth)acrylate (B) having a hydroxyl group, a (meth)acrylic acid urethane (C), and a surfactant. (D) and the photopolymerization initiator (E) are excellent in wettability and diffusibility of a substrate such as an acrylic resin substrate, and the ink is applied onto a substrate such as an acrylic resin substrate by an inkjet method. Hardened, and can be easily formed to have excellent adhesion to the substrate, and the film thickness is 1 A surface liquid-repellent cured film of not more than μm. Further, when a microlens is formed on the surface liquid-repellent cured film obtained from the ink of the present invention by an inkjet method, a microlens having a large ratio of pattern height to pattern diameter (0.18 or more) can be easily formed.

The ink of the present invention may also contain (meth) acrylate (B) and (meth) acrylate other than (meth) acrylate (C), as needed within the scope of the gist of the present invention. (F), a polymerization inhibitor, a thermosetting compound other than an epoxy compound, a flame retardant, a thermal polymerization initiator, an antioxidant, a decane coupling agent, and the like.

The ink of the present invention may be colorless or colored. From the viewpoint of transmittance, it is preferably colorless, but may contain a trace amount of a colored compound insofar as it does not impair the effects of the invention. For example, when the state of the cured film is inspected, a coloring agent may be contained in order to easily distinguish it from the substrate. In these cases, it is preferred that the color of the cured film is not yellowish, and for example, a blue coloring agent can be used.

In the present specification, "(meth) acrylate" is used to mean either or both of an acrylate and a methacrylate. The "epoxy compound" means a compound having an epoxy group (ethylene oxide).

<1.1. Organic Solvent (A)>

The ink of the present invention contains 40 wt% to 98 wt% of the organic solvent (A) with respect to 100 wt% of the ink. When the content of the solvent (A) is in the above range, an ink excellent in wettability and diffusibility to a substrate can be obtained, and a surface-repellent cured film having a small film thickness (for example, 1 μm or less) can be formed by an inkjet method. . The above solvent is 100 wt% of the ink of the present invention The content of (A) is preferably from 50% by weight to 90% by weight, more preferably from 50% by weight to 70% by weight. On the other hand, when the content of the solvent (A) is less than 40% by weight, the obtained ink tends to have poor wettability with respect to the substrate, and the obtained cured film is likely to be thick and easy to be colored. (Yellow) tendency.

Further, when the solvent (A) is an organic solvent having a boiling point of 100 ° C to 300 ° C, the obtained ink is wetted and spread on the substrate when applied to a substrate such as an acrylic resin substrate by an inkjet method. In addition, it is preferable to form a surface liquid-repellent cured film having a uniform film thickness, and further, a compound having a hydroxyl group is used as the solvent (A), and an ink which is less likely to cause clogging of the ink jet head can be obtained. Therefore, it is better.

Specific examples of the organic solvent having a boiling point of 100 ° C to 300 ° C include butyl acetate, butyl propionate, ethyl lactate, methyl methoxyacetate, ethyl methoxyacetate, and methoxyacetic acid. Ester, methyl ethoxyacetate, ethyl ethoxyacetate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, 3-ethoxy Ethyl propyl propionate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, methyl acetate, ethyl acetate, dioxane, 3-methoxybutanol, 3-methoxy Butyl acetate, methyl 2-hydroxyisobutyrate, isopropyl 2-hydroxyisobutyrate, isobutyl 2-hydroxyisobutyrate, n-butyl 2-hydroxyisobutyrate, propylene glycol monomethyl ether, Propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, propylene glycol monophenyl ether, ethylene glycol monobutyl ether, ethylene glycol monophenyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethyl Glycol monopropyl ether, diethylene glycol monobutyl ether, diethylene glycol monophenyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monopropyl ether, dipropylene Glycol monobutyl ether, dipropylene glycol monophenyl ether, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, glycerin, benzyl alcohol, cyclohexanol, 1,4-butanediol, triethylene glycol, tripropylene glycol , tripropylene glycol methyl ether, tripropylene glycol monobutyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether acetate Ester, dipropylene glycol monobutyl ether acetate, ethylene glycol monomethyl ether acetate, ethylene glycol monobutyl ether acetate, cyclohexanone, cyclopentanone, diethylene glycol monomethyl ether acetate, Diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol methyl ethyl ether, dipropylene glycol Ether, toluene, xylene, anisole, γ-butyrolactone, N,N-dimethylacetamide, N-methyl-2-pyrrolidone and dimethylimidazolidinone.

Further, specific examples of the compound having a hydroxyl group include propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, propylene glycol monophenyl ether, ethylene glycol monobutyl ether, and ethylene glycol single. Phenyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, diethylene glycol monophenyl ether, dipropylene glycol monomethyl ether, dipropylene glycol Monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monobutyl ether, dipropylene glycol monophenyl ether, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, glycerin, benzyl alcohol, cyclohexanol, and 1,4-butyl Glycol.

The solvent (A) is preferably an organic solvent containing 40% by weight or more of the hydroxyl group-containing compound in the entire solvent (A).

As the solvent (A), it is preferred to use an organic solvent containing 40 wt% or more of the entire solvent (A) as a viewpoint of obtaining a surface liquid-repellent cured film having a high film thickness uniformity. The compound is selected from Propylene glycol monomethyl ether, propylene glycol monobutyl ether, propylene glycol monophenyl ether, ethylene glycol monophenyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, in the above organic solvent, A compound of diethylene glycol monophenyl ether and dipropylene glycol monomethyl ether.

The solvent (A) used in the ink of the present invention may be one type of compound or a mixture of two or more types of compounds.

<1.2. Difunctional or lower (meth) acrylate having a hydroxyl group (B)>

The ink of the present invention contains a difunctional or lower (meth) acrylate (B) having a hydroxyl group (hereinafter also referred to as "compound (B)"). When the ink of the present invention contains the compound (B), it is possible to form a surface liquid-repellent cured film having excellent adhesion to a substrate, and it is possible to obtain a surface which is less likely to be peeled off from the substrate even when used for a long period of time, and which is excellent in reliability. Liquid hardening film.

In addition, the "difunctional (meth) acrylate" means a (meth) acrylate having two or less (meth) acrylonitrile groups in one molecule.

From the viewpoint of obtaining a surface liquid-repellent cured film having excellent adhesion to a substrate, the compound (B) is preferably selected from the group consisting of the compound represented by the above formula (1) and glycerol alone (A). At least one compound of the group consisting of acrylate, glycerol di(meth)acrylate, and 2-hydroxy-3-propenyl-oxypropyl (meth)acrylate.

Further, in the above formula (1), for example, when n is 2 or more, the compound has a plurality of R ^a . In this case, any two R ^a may be the same or different. This rule also applies to other forms.

As the above compound (B), it is possible to obtain better adhesion to the substrate. From the viewpoint of a different surface liquid-repellent cured film or the like, it is preferably selected from the group consisting of 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and (meth)acrylic acid-3. -hydroxypropyl ester, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and 1,4-cyclohexanedimethanol At least one compound of the group consisting of mono(meth)acrylates.

As the compound (B), a compound produced by a known method can be used, and a commercially available product can also be used.

As a commercial item, Blemmer GMR (trade name, glycerin dimethacrylate, manufactured by Nippon Oil Co., Ltd.), 4-hydroxybutyl acrylate (manufactured by Nippon Kasei Co., Ltd.), and 1,4- Cyclohexane dimethanol monoacrylate (manufactured by Nippon Kasei Co., Ltd.).

The compound (B) used in the ink of the present invention may be one type of compound or a mixture of two or more types of compounds.

In the ink of the present invention, the compound (B) is contained in an amount of 10% by weight to 60% by weight based on the weight of the compound (B), the weight of the compound (C), and the weight of the compound (F): 100% by weight. %, a surface liquid-repellent cured film excellent in adhesion to an acrylic resin substrate can be obtained. Therefore, the content of the compound (B) is preferably from 12% by weight to 55% by weight, and more preferably 15% by weight. ~50 wt%.

<1.3. (Meth)acrylic acid urethane (C)>

The ink of the present invention contains (meth)acrylic acid urethane (C) (hereinafter also referred to as "compound (C)"). Further, the compound (C) is a compound other than the above compound (B). The surface liquid-repellent cured film obtained from the ink containing the compound (C) has a uniform film thickness uniformity for the acrylic tree It is preferable that the substrate such as a grease substrate is excellent in adhesion to each other and is hardened (high sensitivity) with a small amount of exposure, and is a surface-repellent cured film having a small thickness of 1 μm or less.

From the viewpoint of obtaining an ink excellent in photocurability and easily forming a surface liquid-repellent cured film, etc., it is preferred to use a compound represented by the above formula (2) as the compound (C).

In the above formula (2), each of R ¹ and R ^{3 is} independently a divalent organic group having a carbon number of 1 to 20, and a surface-repellent cured film having a uniform film thickness uniformity can be obtained. Preferably, each is independently an alkylene group having a carbon number of 1 to 10,

R ² is a divalent organic group having a carbon number of 1 to 20, and is preferably selected from the above group (a) from the viewpoint of obtaining a surface liquid-repellent cured film having a uniform film thickness uniformity. a divalent base,

m and n are each independently an integer of 1 to 3. From the viewpoint of the curability of the ink, etc., it is preferably 2 or 3, and more preferably 3, respectively.

It is preferable to use a component containing a compound represented by the following formula (3) from the viewpoint of obtaining an ink having a more excellent photocurability and a surface-repellent cured film having a more uniform film thickness. As the above compound (C). NK OLIGO U-6LPA (trade name, manufactured by Shin-Nakamura Chemical Industry Co., Ltd.), etc. are mentioned as a component containing the compound represented by the following formula (3).

The compound (C) used in the ink of the present invention may be one type of compound or a mixture of two or more types of compounds.

In the ink of the present invention, the compound (C) is contained in an amount of 10% by weight to 60% by weight based on the weight of the compound (B), the weight of the compound (C), and the weight of the compound (F): 100% by weight. %, an ink excellent in photocurability is obtained, and a surface liquid-repellent cured film having excellent film thickness uniformity can be obtained. Therefore, the content of the compound (C) is preferably 15 wt% to 45 wt%. More preferably, it is 20 wt% to 35 wt%.

<1.4. Surfactant (D)>

The ink of the present invention contains a surfactant (D). When the surfactant (D) is contained, the surface liquid-repellent film obtained has a high surface liquid repellency, which is preferable.

Specific examples of the surfactant (D) include Polyflow No. 45, Polyflow KL-245, Polyflow No. 75, Polyflow No. 90, and Polyflow No. 95 (trade name, Kyoeisha Chemical Industry Co., Ltd.) Manufacturing), Disperbyk161, Disperbyk162, Disperbyk163, Disperbyk164, Disperbyk166, Disperbyk170, Disperbyk180, Disperbyk181, Disperbyk182, BYK300, BYK306, BYK310, BYK320, BYK330, BYK344, BYK346 (trade name, BYK-Chemie Japan (share) manufacturing), KP- 341, KP-358, KP-368, KF-96-50CS, KF-50-100CS (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.), Surflon SC-101, Surflon KH-40 (trade name, Seimi Chemical (share) Manufacturing), Ftergent 222F, Ftergent 251, FTX-218 (trade name, manufactured by Neos), EFTOP EF-351, EFTOP EF-352, EFTOP EF-601, EFTOP EF-801, EFTOP EF-802 (trade name, Mitsubishi) Manufacture of materials (shares), Megafac F-171, Megafac F-177, Megafac F-475, Megafac R-08, Megafac R-30 (trade name, manufactured by DIC), fluoroalkylbenzenesulfonate, , fluoroalkyl carboxylate, fluoroalkyl polyoxyethylene ether, fluoroalkyl ammonium iodide, fluoroalkyl betaine, fluoroalkyl sulfonate, diglycerol tetra (fluoroalkyl polyoxygen) Vinyl ether), fluoroalkyltrimethylammonium salt, fluoroalkylaminosulfonate, polyoxyethylene nonylphenyl ether, polyoxyethylene octylphenyl ether, polyoxyethylene lauryl ether, Polyoxyethylene oleyl ether, polyoxyethylene tridecyl ether, polyoxyethylene hexadecyl ether, polyoxyethylene stearyl ether, polyoxyethylene laurate, polyoxyethylene oleate, Polyoxyethylene stearate , polyoxyethylene laurylamine, sorbitan laurate, sorbitan palmitate, sorbitan stearate, sorbitan oleate, sorbitan Fatty acid ester, polyoxyethylene sorbitan laurate, polyoxyethylene sorbitan palmitate, polyoxyethylene sorbitan stearate, polyoxyethylene sorbitan oil An acid ester, a polyoxyethylene naphthyl ether, an alkylbenzene sulfonate, and an alkyl diphenyl ether disulfonate.

In addition, when the surfactant (D) is a fluorine-based surfactant or an anthrone-based surfactant, the surface liquid-repellent cured film obtained has a higher surface liquid repellency, which is preferable. In particular, if the surfactant (D) is an anthrone In the case of a surfactant, when a microlens is formed on the obtained surface liquid-repellent cured film by an inkjet method, a microlens having a small variation in size and a large ratio of pattern height to pattern diameter can be obtained, which is preferable. .

Further, when the surfactant (D) is a compound having at least one reactive group, even an ink containing a large amount of the solvent (A) is preferred as an ink having high curability. The reactive group is preferably at least 1 selected from the group consisting of a (meth) acryl fluorenyl group, an epoxy group, and an oxetanyl group, from the viewpoint of obtaining an ink having high curability. Base.

Specific examples of the surfactant having a (meth)acryl fluorenyl group as a reactive group include RS-72K (trade name, manufactured by DIC), BYK UV 3500, and BYK UV 3570 (trade name, BYK). - manufactured by Chemie Japan (trade), TEGO Rad 2200N, TEGO Rad 2250, TEGO Rad 2300, TEGO Rad 2500 (trade name, manufactured by Evonik Degussa Japan).

In addition, examples of the surfactant having an epoxy group as a reactive group include RS-211K (trade name, manufactured by DIC).

The surfactant (D) used in the ink of the present invention may be one type of compound or a mixture of two or more types of compounds.

In the ink of the present invention, if the weight of the compound (B) and the weight of the compound (C) and the weight ratio of the surfactant (D) ((B) + (C): (D)) are 1000:1 In the range of ～1, the balance between the photocurability of the ink and the liquid repellency of the obtained cured film surface is sufficiently excellent, which is preferable. Further, the weight ratio (B) + (C): (D) is preferably in the range of 500:1 to 2:1, more preferably in the range of 200:1 to 5:1, and particularly preferably in the range of 100:1. A range of 10:1.

<1.5. Photopolymerization initiator (E)>

The ink of the present invention contains a photopolymerization initiator (E). The photopolymerization initiator (E) is not particularly limited as long as it is a compound capable of generating a radical by irradiation with ultraviolet rays (UV) or visible light, but is preferably α-hydroxyalkylphenone (α). -hydroxyalkylphenone) is a photopolymerization initiator, a mercaptophosphine oxide photopolymerization initiator, and a hydroxyphenyl acetate photopolymerization initiator, in particular, the photocurability of the ink, the obtained surface From the viewpoint of the transmittance of the liquid repellent film and the like, a hydroxyphenyl acetate photopolymerization initiator is more preferable.

Specific examples of the photopolymerization initiator (E) include diphenyl ketone, rice ketone, 4,4'-bis(diethylamino)diphenyl ketone, xanthone, and thia. Anthrone, isopropyl oxa ketone, 2,4-diethyl thioxanthone, 2-ethyl hydrazine, acetophenone, 2-hydroxy-2-methyl-4'-isopropylbenzene Acetone, isopropyl benzoin ether, isobutyl benzoin ether, 2,2-diethoxyacetophenone, 2,2-dimethoxy-1,2-diphenylethane-1-one, camphor Anthracene, benzoxanthone, ethyl 4-dimethylaminobenzoate, isoamyl 4-dimethylaminobenzoate, 4,4'-di(t-butylcarbonyl)diphenyl ketone, 3,4,4'-tris(t-butylcarbonyl peroxy)diphenyl ketone, 3,3',4,4'-tetra(perbutylbutoxycarbonyl)diphenyl ketone, 3,3 ',4,4'-tetra(peroxylated hexylcarbonyl)diphenyl ketone, 3,3'-bis(methoxycarbonyl)-4,4'-di(t-butylcarbonyl)peroxide Phenyl ketone, 3,4'-bis(methoxycarbonyl)-4,3'-di(t-butylperoxycarbonyl)diphenyl ketone, 4,4'-bis(methoxycarbonyl)- 3,3'-di(t-butylcarbonyl)diphenyl ketone, 2-(4'-methoxystyryl)-4,6-bis(trichloromethyl)-all Pyrazine, 2-(3',4'-dimethoxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 2-(2',4'-dimethoxybenzene Vinyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(2'-methoxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4'-pentyloxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 4-[p-N,N-bis(ethoxycarbonylmethyl)]-2 ,6-bis(trichloromethyl)-s-triazine, 1,3-bis(trichloromethyl)-5-(2'-chlorophenyl)-s-triazine, 1,3-bis(trichloro) Methyl)-5-(4'-methoxyphenyl)-s-triazine, 2-(p-dimethylaminostyryl)benzoxazole, 2-(p-dimethylaminostyryl) Benzothiazole, 2-mercaptobenzothiazole, 3,3'-carbonyl bis(7-diethylaminocoumarin), 2-(o-chlorophenyl)-4,4',5,5'-four Phenyl-1,2'-biimidazole, 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetrakis(4-ethoxycarbonylphenyl)-1,2 '-Biimidazole, 2,2'-bis(2,4-dichlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2,2'-double (2,4-dibromophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2,2'-bis(2,4,6-trichlorophenyl) -4,4',5,5'-tetraphenyl-1,2'-biimidazole, 3-(2-methyl-2-dimethylaminopropionyl)carbazole, 3,6-double (2-methyl-2-? Phenylpropenyl)-9-n-dodecylcarbazole, bis(η ⁵ -2,4-cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1H-pyrrole) -1-yl)-phenyl)titanium, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-1-propanone, 1-[4-(2-hydroxyethoxy) )-phenyl]-2-hydroxy-2-methyl-1-propanone, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propenyl)-benzyl]benzene -2--methyl-1-propanone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinyl-1-propanone, 2-(dimethylamino)- 1-(4-morpholinylphenyl)-2-benzyl-1-butanone, 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4 -(4-morpholinyl)phenyl]-1-butanone, 2-[2-o-oxy-2-phenyl-ethyloxy-ethoxy]-ethyl hydroxyphenylacetate, hydroxybenzene 2-[2-hydroxy-ethoxy]-ethyl acetate, 2-[2-o-oxy-2-phenyl-ethoxycarbonyl-ethoxy]-ethyl hydroxyphenylacetate and hydroxybenzene a mixture of 2-[2-hydroxy-ethoxy]-ethyl acetate, methyl benzomethionate, bis(2,4,6-trimethylbenzylidene)phenylphosphine oxide, 2, 4,6-trimethylbenzimidyldiphenylphosphine oxide, 2,4,6-trimethylbenzimidyldiphenylphosphinate, 1-[4-(phenylthio)phenyl ]-1,2-octanedione 2-(O-benzene Methyl hydrazide)], 1-[9-ethyl-6-(2-methylbenzhydryl)-9H-indazol-3-yl]-ethanone-1-(O-ethyl fluorenyl hydrazide ).

Among them, 2-hydroxy-2-methyl-1-phenyl-1-propanone, 2-hydroxy-2-methyl-4'-isopropylpropiophenone, 1-hydroxycyclohexyl phenyl ketone, 2-[2-Sideoxy-2-phenyl-ethoxycarbonyl-ethoxy]-ethyl hydroxyphenylacetate, 2-[2-hydroxy-ethoxy]-ethyl hydroxyphenylacetate, 2-[2-Sideoxy-2-phenyl-ethoxycarbonyl-ethoxy]-ethyl hydroxyphenylacetate and 2-[2-hydroxy-ethoxy]-ethyl hydroxyphenylacetate a mixture, methyl benzomethionate, bis(2,4,6-trimethylbenzylidene)phenylphosphine oxide and 2,4,6-trimethylbenzimidyldiphenylphosphine oxide,

More preferably 2-[2-o-oxy-2-phenyl-ethyloxy-ethoxy]-ethyl hydroxyphenylacetate, 2-[2-hydroxy-ethoxy]-hydroxyphenylacetate Ethyl ester, 2-[2-oxo-2-phenyl-ethoxycarbonyl-ethoxy]-ethyl ester of hydroxyphenylacetate and 2-[2-hydroxy-ethoxy]-hydroxyphenylacetate A mixture of ethyl esters, methyl benzomethionate, and 2,4,6-trimethylbenzimidyldiphenylphosphine oxide.

The commercially available product of the photopolymerization initiator (E) may, for example, be Irgacure 184, Irgacure 651, Irgacure 127, DAROCUR 1173, Irgacure 500, Irgacure 2959, Irgacure 754, DAROCUR MBF, Lucirin TPO (trade name, manufactured by BASF Japan).

Among these, Irgacure 754, DAROCUR MBF, and Lucirin TPO (trade name, manufactured by BASF Japan) are preferable.

The photopolymerization initiator (E) used in the ink of the present invention may be one type of compound or a mixture of two or more types of compounds.

In the ink of the present invention, the photopolymerization initiator (E) is contained in an amount of 1 part by weight based on the weight of the compound (B), the weight of the compound (C), and 100 parts by weight of the compound (F). When the amount is 50 parts by weight, an ink excellent in photocurability to ultraviolet light can be obtained, and a surface liquid-repellent cured film having high light transmittance can be obtained. Therefore, the content of the photopolymerization initiator (E) is preferably higher. It is 1 part by weight to 40 parts by weight, and more preferably 5 parts by weight to 30 parts by weight.

<1.6. Compound (B) and (meth) acrylate (F) other than the compound (C)>

The ink of the present invention may further contain the above compound (B) and a compound in order to appropriately adjust the relationship between the solid content concentration and the viscosity in the ink or to improve the applicability (wet diffusibility) to various substrates, particularly acrylic substrates. (Meth) acrylate (F) other than (C) (hereinafter abbreviated as "compound (F)").

Specific examples of the compound (F) include pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate, and Dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, trimethylolpropane tri (meth) acrylate, di-trimethylolpropane tetra (meth) acrylate, bisphenol F ethylene oxide modified di(meth)acrylate, bisphenol A ethylene oxide modified di(meth)acrylate, polyethylene glycol di(meth)acrylate, polypropylene glycol di(methyl) Acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1 , 4-cyclohexanedimethanol di(meth)acrylate, 2-n-butyl-2-ethyl-1,3-propanediol di(meth)acrylate, diethylene glycol di(meth)acrylic acid Ester, neopentyl glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, ethylene oxide modified trimethylolpropane tri(meth)acrylate, propylene oxide modification Trimethylolpropane tris(A) Acrylate, epichlorohydrin modified trimethylolpropane tri (meth) acrylate, glycerol tri(meth) acrylate, epichlorohydrin modified glycerol tri(meth) acrylate, diglycerol tetra (A) Acrylate, iso-cyanuric acid ethylene oxide modified tris(meth)acrylate, ε-caprolactone modified three ( Ethyl)isocyanate, tricyclodecane dimethanol di(meth)acrylate, alkoxylated cyclohexanedimethanol di(meth)acrylate, glycidyl (meth)acrylate, -3,4-epoxycyclohexyl (meth)acrylate, methyl glycidyl (meth)acrylate, 3-methyl-3-(methyl)propenyloxymethyloxetane , 3-ethyl-3-(methyl)propenyloxymethyloxetane, 3-methyl-3-(methyl)propenyloxyethyloxetane, 3-B 3-(methyl)propenyloxyethyloxetane, 2-phenyl-3-(methyl)propenyloxymethyloxetane, 2-trifluoromethyl- 3-(Methyl)acryloxymethyloxybutane, 4-trifluoromethyl-2-(methyl)propenyloxymethyloxetane, (meth)acrylic acid, ( Methyl)methyl acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, third butyl (meth) acrylate Ester, cyclohexyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, benzyl (meth)acrylate, (3-ethyl-3-oxetanyl)methyl (meth)acrylate , Isodecyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, tricyclo-(5,2,1,0 ^2.6 )-nonyl ester, tricyclo-(5,2,1,0 ^2.6 )-nonyloxyethyl (meth)acrylate, phenyl (meth)acrylate, 5-tetrahydroindenyl (meth)acrylate Oxycarbonylpentyl ester, lauryl (meth)acrylate, isodecyl (meth)acrylate, stearyl (meth)acrylate, 2-phenoxyethyl (meth)acrylate, lauryl alcohol Ethylene oxide adduct (meth) acrylate, succinic acid mono [2-(methyl) propylene oxiranyl ethyl], maleic acid mono [2-(methyl) propylene oxime Base ethyl], cyclohexene-3,4-dicarboxylic acid mono[2-(methyl)acryloxyethyl).

In the above-mentioned compound (F), it is possible to obtain an ink excellent in wettability and diffusibility to a substrate such as an acrylic resin substrate when applied by an inkjet method, and to obtain a uniform surface thinning liquid. From the viewpoint of the cured film, etc., it is preferably a polyfunctional (meth) acrylate having at least one selected from the group consisting of a cycloalkyl group and a cycloalkyl group, and more preferably a tricyclodecane. Dimethanol diacrylate.

As the compound (F), a compound produced by a known method can be used, and a commercially available product can also be used.

As a commercial item, IRR214-K (trade name, tricyclodecane dimethanol diacrylate, manufactured by Daicel Cytec (share)), Aronix M-208, Aronix M-305 (trade name, East Asia synthesis (share) ) Manufacturing) and so on.

The compound (F) which can be used in the ink of the present invention may be one type of compound or a mixture of two or more types of compounds.

In the ink of the present invention, the compound (F) is 100 parts by weight based on the total amount of the compound (B) and the weight of the compound (C). When the content is from 0 parts by weight to 200 parts by weight, a surface liquid-repellent cured film excellent in wettability and diffusibility of a substrate such as an acrylic resin substrate can be obtained. Therefore, the content of the compound (F) is preferably 35 parts by weight. 170 parts by weight, and more preferably 70 parts by weight to 140 parts by weight.

<1.7. Polymerization inhibitor>

In order to improve storage stability, the ink of the present invention may also contain a polymerization inhibitor. Specific examples of the polymerization inhibitor include 4-methoxyphenol, hydroquinone, and phenothiazine. Among these, when phenothiazine is used, an ink having a small increase in viscosity even after long-term storage can be obtained, which is preferable.

The polymerization inhibitor which can be used in the ink of the present invention may be one type of compound or a mixture of two or more types of compounds.

In the ink of the present invention, when the content of the polymerization inhibitor is from 0.01 part by weight to 1 part by weight based on 100 parts by weight of the total of the weight of the compound (B) and the weight of the compound (C), long-term storage is obtained. The viscosity of the ink is also small, so it is preferable that the concentration of the polymerization inhibitor is preferably from 0.01 part by weight to 0.5 part by weight, and more preferably 0.01 part by weight, in consideration of the balance between storage stability and photocurability. 0.1 parts by weight.

<1.8. Thermosetting compound other than epoxy compound>

The ink of the present invention may contain a thermosetting compound other than the epoxy compound. The thermosetting compound is not particularly limited as long as it is a compound having a functional group capable of thermal curing, and examples thereof include bis-methylene iodide, a phenol resin, a resin containing a phenolic hydroxyl group, and a melamine resin. And epoxy hardeners.

The thermosetting compound other than the epoxy compound which can be used in the ink of the present invention may be one type of compound or a mixture of two or more types of compounds.

In the ink of the present invention, the content of the thermosetting compound other than the epoxy compound is from 2 parts by weight to 50 parts by weight based on 100 parts by weight of the total of the weight of the compound (B) and the weight of the compound (C). Since the heat resistance of the surface liquid-repellent cured film obtained is improved, the content of the thermosetting compound other than the epoxy compound is preferably from 5 parts by weight to 30 parts by weight, and more preferably from 10 parts by weight to 20 parts by weight. Parts by weight.

1.8.1 Bis-m-butylene diimine

The compound represented by the following formula (4) is exemplified as the bis-m-butylene diimine. The bis-n-butylene diimine represented by the following formula (4) can be obtained by reacting, for example, a diamine with an acid anhydride.

In the formula (4), R ¹⁰ and R ¹² each independently represent hydrogen or a methyl group, and R ¹¹ is a divalent group represented by the following formula (5).

In the formula (5), R ¹³ and R ¹⁴ are each independently a non-contiguous (non-adjacent) any methylene group which may be substituted by an oxygen having an alkyl group having 1 to 18 carbon atoms and having an aromatic ring which may have a substituent. A divalent group or a cycloalkyl group which may have a substituent. Examples of the substituent include a carboxyl group, a hydroxyl group, an alkyl group having 1 to 5 carbon atoms, and an alkoxy group having 1 to 5 carbon atoms. From the viewpoint of obtaining a surface-repellent cured film having high heat resistance, it is preferred that R ¹³ and R ¹⁴ each independently be a divalent group selected from the group (8) below.

In the formula (5), X is one divalent group selected from the group (9) below.

The dim-butylene diimine which can be used in the ink of the present invention may be one type The compound may also be a mixture of two or more compounds.

1.8.2 phenol resin or resin containing phenolic hydroxyl group

As the phenol resin, a novolak resin obtained by a condensation reaction of an aromatic compound having a phenolic hydroxyl group and an aldehyde can be preferably used, and as the resin having a phenolic hydroxyl group, a vinylphenol can be preferably used. a polymer (including a hydride), a vinyl phenol-based copolymer (including a hydride) of a compound in which a vinyl phenol is copolymerizable, and the like.

Examples of the aromatic compound having a phenolic hydroxyl group include phenol, o-cresol, m-cresol, p-cresol, o-ethylphenol, m-ethylphenol, p-ethylphenol, o-butylphenol, and m-butyl group. Phenol, p-butylphenol, 2,3-xylenol (xylenol), 2,4-xylenol, 2,5-xylenol, 2,6-xylenol, 3,4-xylenol, 3,5-xylenol, 2,3,5-trimethylphenol, 3,4,5-trimethylphenol, p-phenylphenol, resorcinol, hydroquinone , hydroquinone monomethyl ether, pyrogallol, bisphenol A, bisphenol F, terpene containing terpene, gallic acid, gallic acid ester, α-naphthol, And β-naphthol and the like.

Examples of the aldehydes include formaldehyde, trioxane, furfural, benzaldehyde, nitrobenzaldehyde, and acetaldehyde.

Examples of the compound copolymerizable with vinylphenol include (meth)acrylic acid or a derivative thereof, styrene or a derivative thereof, maleic anhydride, vinyl acetate, and acrylonitrile.

Specific examples of the phenol resin or the phenolic hydroxyl group-containing resin include Resitop PSM-6200 (trade name, manufactured by Qunrong Chemical Industry Co., Ltd.), and Shonol BRG-555 (trade name, manufactured by Showa Denko (share)). ), Maruka Lyncur MS-2P, Maruka Lyncur CST70, Maruka Lyncur PHM-C (trade name, manufactured by Maruzen Petrochemical Co., Ltd.).

The phenol resin or the phenolic hydroxyl group-containing resin which can be used in the ink of the present invention may be one type of compound or a mixture of two or more types of compounds.

1.8.3 Melamine resin

The melamine resin is not particularly limited as long as it is a resin produced by polycondensation of melamine and formaldehyde, and examples thereof include methylol melamine, etherified methylol melamine, benzoguanamine, and methylol benzoguanamine. And a condensate such as etherified methylol benzoguanamine or the like. Among these, a condensate of etherified methylol melamine is preferred from the viewpoint that the chemical resistance of the surface liquid-repellent cured film obtained is good.

Specific examples of the melamine resin include Nikalac MW-30, MW-30HM, MW-390, MW-100LM, and MX-750LM (trade name, manufactured by Sanwa Chemical Co., Ltd.).

The melamine resin which can be used in the ink of the present invention may be one type of compound or a mixture of two or more types of compounds.

1.8.4 epoxy hardener

In order to further improve the chemical resistance of the obtained surface liquid-repellent cured film, the ink of the present invention may also contain an epoxy hardener. The epoxy curing agent is preferably an acid anhydride curing agent or a polyamine curing agent.

Examples of the acid anhydride-based curing agent include maleic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, hexahydrotrimellitic anhydride, and o-benzene. Dicarboxylic anhydride, trimellitic anhydride, and styrene-maleic anhydride copolymer, and the like.

Examples of the polyamine-based curing agent include diethylenetriamine, triethylenetetramine, tetraethylenepentamine, dicyandiamide, polyamidamine (polyamine resin), ketimine compound, and isophorone. Diamine, m-xylylenediamine, m-phenylenediamine, 1,3-bis(aminomethyl)cyclohexane, N-aminoethylpiperazine, 4,4'-diaminodiphenylmethane And 4,4'-diamino-3,3'-diethyldiphenylmethane, and diaminodiphenylanthracene.

The epoxy curing agent which can be used in the ink of the present invention may be one type of compound or a mixture of two or more types of compounds.

<1.9. Flame Retardant>

The ink of the present invention may also contain a flame retardant. When the ink of the present invention contains a flame retardant, a surface liquid-repellent cured film having high flame retardancy can be obtained, which is preferable. The flame retardant is not particularly limited as long as it is a compound capable of imparting flame retardancy, but an organic phosphorus-based flame retardant is preferably used from the viewpoint of low toxicity, low pollution, safety, and the like.

Examples of the organic phosphorus-based flame retardant include triphenyl phosphate, tricresyl phosphate, tris(xylylene) phosphate, tolylphenyl phosphate, 2-ethylhexyl diphenyl phosphate, and 9,10-di. Hydrogen-9-oxa-10-phosphaphenanthrene-10 oxide, 10-(2,5-dihydroxyphenyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide, and condensation 9,10-Dihydro-9-oxa-10-phosphaphenanthrene-10 oxide.

As a flame retardant, even when the obtained surface liquid-repellent cured film is exposed to a high temperature state, the bleeding of the flame retardant is less likely to occur, and it is preferred to use the following formula (6). ) a compound of the structure indicated. The compound having a structure represented by the following formula (6) is preferably a compound represented by the following formula (7), and the following formula (7) is used. The compound to be represented includes a condensed 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10 oxide.

The commercially available product of the compound represented by the following formula (7) includes HFA-3003 (trade name, manufactured by Showa Denko (share)).

In the formula (7), m is an integer of 0 to 2, n is an integer of 1 to 3, and m+n is 3. Preferably, m is 1 or 2, n is 1 or 2, and m+n is 3.

The flame retardant which can be used in the ink of the present invention may be one type of compound or a mixture of two or more types of compounds.

In addition, as the flame retardant, a compound produced by a known method may be used, and a commercially available product such as HFA-3003 (trade name) manufactured by the Showa Denko (share) may be used.

When the content of the flame retardant used in the ink of the present invention is from 15 parts by weight to 30 parts by weight based on 100 parts by weight of the total of the weight of the compound (B) and the weight of the compound (C), the obtained surface is obtained. The flame retardancy of the liquid repellent film is improved, so that the content of the flame retardant is more preferably from 20 parts by weight to 25 parts by weight.

<1.10. Thermal polymerization initiator>

In order to enhance the hardenability of the ink by a heating step, the ink of the present invention may further contain a thermal polymerization initiator. Specific examples of the thermal polymerization initiator include 2,2'-azobisisobutyronitrile, 2,2'-azobis(2,4-dimethylvaleronitrile), and benzammonium peroxide. , di-tert-butyl peroxide. Among these, 2,2'-azobisisobutyronitrile and 2,2'-azobis(2,4-dimethylvaleronitrile) are preferred.

The thermal polymerization initiator which can be used in the ink of the present invention may be one type of compound or a mixture of two or more types of compounds.

<1.11. Antioxidants>

The ink of the present invention may contain an antioxidant in terms of improving the transparency of the surface liquid-repellent cured film obtained and preventing yellowing when exposed to a high temperature. Specific examples of the antioxidant include a hindered amine-based antioxidant and a hindered phenol-based antioxidant. Specific examples include IRGAFOS XP40, IRGAFOS XP60, IRGANOX 1010, IRGANOX 1035, IRGANOX 1076, IRGANOX 1135, IRGANOX 1520L (trade name, manufactured by BASF Japan).

The antioxidant which can be used in the ink of the present invention may be one type of compound or a mixture of two or more types of compounds.

<1.12. Decane coupling agent>

The ink of the present invention may also contain a decane coupling agent in order to enhance the adhesion of the obtained surface liquid-repellent cured film to the substrate.

Specific examples of the decane coupling agent include 3-propenyloxypropyltrimethoxydecane, 3-methylpropenyloxypropyltrimethoxydecane, and 3-glycidoxypropyltrimethoxy. Decane, 3-glycidoxypropyltriethoxydecane, 3-aminopropyltrimethoxydecane, and 3-mercaptopropyltrimethoxydecane.

Among these, 3-propenyloxypropyltrimethoxydecane, 3-methacryloxypropyltrimethoxydecane, and 3-glycidoxypropyltrimethoxydecane have reactive groups. It is preferably copolymerized with other components.

The decane coupling agent which can be used in the ink of the present invention may be one type of compound or a mixture of two or more types of compounds.

<1.13. Viscosity of ink>

The viscosity of the ink of the present invention at 25 ° C as measured by an E-type viscometer is preferably 1.0 mPa. s~30 mPa. s. When the viscosity is in this range, when the ink of the present invention is applied by an inkjet method, the discharge property by the inkjet device becomes good. The viscosity of the ink of the present invention at 25 ° C is preferably 1.2 mPa. s~25 mPa. s, especially good for 1.5 mPa. s~20 mPa. s.

<1.14. Method for preparing ink>

The ink of the present invention can be prepared by mixing the components which are raw materials by a known method.

In particular, the ink of the present invention is preferably prepared by mixing the above components (A) to (E) and optionally other components, and then using, for example, a fluorine tree. A lipid membrane filter was prepared by filtering and degasing the obtained solution. The ink prepared in the above manner is excellent in discharge property at the time of coating by an inkjet method.

<1.15. Preservation of ink>

When the ink of the present invention is stored at -20 ° C to 25 ° C, the viscosity increase during storage is small, and the storage stability is good.

[2. Coating of ink by inkjet method]

The ink of the present invention can be applied by a known inkjet method. Examples of the inkjet method include a piezoelectric method in which mechanical energy is applied to the ink to eject the ink from the inkjet head, and a coating method in which thermal energy is applied to the ink to eject the ink (so-called thermal induction method).

By using the inkjet method, the ink of the present invention can be easily applied into a predetermined pattern to form a uniform pattern on a large substrate.

Examples of the ink jet head include an ink jet head including a heat generating portion including a metal and/or a metal oxide. Specific examples of the metal and/or metal oxide include metals such as Ta, Zr, Ti, Ni, and Al, and oxides of these metals.

As a preferable coating apparatus used for coating by the ink of the present invention, for example, an apparatus for supplying ink corresponding to a coating signal to an ink in an ink jet head having an ink containing portion for storing ink is provided. The energy is applied (painting) corresponding to the coating signal while generating ink droplets by the energy.

The inkjet coating device is not limited to a coating device in which the inkjet head is separated from the ink containing portion, and the inkjet head and the ink containing portion may not be separated. As one of the coating devices. Further, the ink accommodating portion may be integrated with the ink jet head or separated from each other and mounted on the bracket, or may be provided at a fixed portion of the device. In the latter case, the ink may be supplied to the inkjet head via an ink supply member such as a tube.

[3. Use of ink]

Since the ink of the present invention is excellent in wettability and diffusibility to a substrate, in particular, an acrylic resin substrate, it can be preferably used for production of an optical device such as an image display device, and for manufacturing an optical component having a microlens used in a backlight unit. Specifically, it can be preferably used for liquid-repelling treatment or the like on the surface of the substrate when the microlens array is manufactured. Further, the ink according to the present invention can be formed into a surface-repellent cured film which is excellent in adhesion to a substrate, in particular, an acrylic resin substrate, and which is less likely to be peeled off from the substrate even when used for a long period of time, and is excellent in reliability. Since optical components such as a light guide plate having a small amount of color are used, the ink is useful for producing a high-quality image display device.

Further, according to the ink of the present invention, it is also possible to increase the size of the optical component or the image display device.

[4. Surface liquid-repellent hardening film]

The surface liquid-repellent cured film of the present invention is obtained by curing the ink of the present invention, and it is preferred to apply the ink of the present invention to the surface of the substrate by an inkjet method, and then irradiate light such as ultraviolet rays or visible rays. A film obtained by hardening it.

The amount of light (exposure amount) to be irradiated when irradiated with ultraviolet rays or visible rays or the like may be appropriately adjusted in accordance with the composition of the ink, but is preferably 100 mJ/cm ² to 5,000 mJ/cm ² , more preferably 200 mJ. /cm ² to 4,000 mJ/cm ² , and more preferably 300 mJ/cm ² to 3,000 mJ/cm ² . Further, the wavelength of the ultraviolet ray or the visible ray to be irradiated is preferably from 200 nm to 500 nm, more preferably from 250 nm to 450 nm.

In the present invention, the exposure amount is a value measured by an integrated light meter UIT-201 (trade name) equipped with a light receiver UVD-365PD (trade name) manufactured by Ushio Electric Co., Ltd.

When irradiating light, an exposure apparatus may be used. As the exposure apparatus, a low-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high pressure mercury lamp, a metal halide lamp, a halogen lamp, or the like may be mounted, and ultraviolet rays may be irradiated in a range of 200 nm to 500 nm. The device such as visible light or the like is not particularly limited.

The substrate to be coated with the ink of the present invention is not particularly limited as long as it can be a target for ink application, and the shape thereof is not limited to a flat plate shape, and may be a curved shape.

The substrate is not particularly limited, and examples thereof include a polyester resin substrate including polyethylene terephthalate (PET) and polybutylene terephthalate (PBT). a polyolefin resin substrate comprising polyethylene, polypropylene, polystyrene or the like; an organic polymer film comprising polyvinyl chloride, fluororesin, acrylic resin, polyamine, polycarbonate, and polyimine; Cell (cellophane); metal foil; laminated film of polyimide and metal foil; using cellophane, parchment, polyethylene, clay binder, polyvinyl alcohol, starch or carboxymethyl cellulose (Carboxymethyl Cellulose) with filling effect , CMC), etc., which are filled with paper; and a glass substrate.

Among these, an acrylic resin substrate is preferably used.

As the substrate, a substrate containing an additive such as an antioxidant, an anti-deterioration agent, a filler, an ultraviolet absorber, an antistatic agent, and/or an anti-electromagnetic wave agent may be used as long as it does not adversely affect the effects of the present invention. Further, as the substrate, at least a part of the surface of the substrate may be subjected to a corona treatment, a plasma treatment, or a blast treatment, which may be easily treated, or may be provided with an easy adhesion layer or a hard coating on the surface. The substrate of the film.

The thickness of the substrate is not particularly limited, but is usually 10 μm to 10 mm, and is appropriately adjusted depending on the purpose of use.

The film thickness of the surface liquid-repellent cured film of the present invention is not particularly limited, but is preferably 1 μm or less, and more preferably 0.5 μm or less in terms of optical characteristics.

When the film thickness of the surface liquid-repellent cured film of the present invention is in the above range, it becomes a cured film which is less likely to be colored (yellow), and therefore it can be preferably used for formation of a light guide plate which is less likely to be colored (yellow).

Since the ink of the present invention is excellent in wettability and diffusibility to a substrate, in particular, an acrylic resin substrate, when a film such as a cover substrate is formed on a substrate, even if the resolution of printing is low, a uniform surface discharge of the film surface can be obtained. Sclerotherapy film. Therefore, a surface liquid-repellent cured film having a small film thickness can be formed.

On the other hand, since the previous ink has poor wettability with respect to the substrate, particularly the acrylic resin substrate, if the resolution of printing is not high, it is difficult to form a film such as a cover substrate, and therefore, in many cases, it is easy to form coloring. A thick film with a thick film.

The surface liquid-repellent cured film of the present invention is excellent in adhesion to a substrate such as an acrylic resin substrate, and can be thinned, and exhibits high light transmittance and high transmittance. In particular, it is preferably used for the production of a microlens used in a backlight unit or the like, and specifically, it is preferably used for forming a liquid-repellent film provided on the surface of the substrate when the microlens array is manufactured.

[5. Microlens]

The microlens of the present invention is formed on the surface liquid-repellent cured film of the present invention described above by an inkjet method. Therefore, a microlens having a small deviation between the pattern diameter and the height can be easily formed.

In the case of forming the microlens, the ink for forming a microlens may be used, and the ink is not particularly limited, and a conventionally known ink can be used.

Further, the method of forming the microlens is not particularly limited, and may be appropriately adjusted in accordance with the ink to be used.

The lens diameter of the above microlens is not particularly limited, but is usually preferably 10 μm to 100 μm, more preferably 15 μm to 60 μm, and particularly preferably 20 μm to 50 μm. The height of the lens is also not particularly limited, and is usually preferably 0.5 μm to 30 μm, more preferably 1 μm to 20 μm, and particularly preferably 2 μm to 15 μm.

In addition, the ratio of the lens height to the lens diameter is not particularly limited. However, from the viewpoint of producing an optical component having excellent light extraction efficiency, etc., it is preferably 0.18 or more, and more preferably 0.2 or more.

[6. Optical parts]

The optical component of the present invention has the above microlens. Therefore, it is an optical component excellent in optical characteristics. As the optical component, a light guide plate or the like can be cited.

[7. Image display device]

The image display device of the present invention includes the above optical component. Therefore, its It is an image display device with excellent characteristics.

[Example]

The invention is further illustrated by the following examples, but the invention is not limited by the examples. In addition, hereinafter, the photocurable inkjet ink obtained in the examples may be simply referred to as ink. That is, for example, the photocurable inkjet ink 1 may be referred to as the ink 1.

[Example 1]

Propylene glycol monomethyl ether (hereinafter abbreviated as "PGME") as a solvent (A) and 4-hydroxybutyl acrylate (product name, manufactured by Nippon Kasei Co., Ltd.) as a solvent (A) NK OLIGO U-6LPA (trade name, manufactured by Shin-Nakamura Chemical Co., Ltd.) as a component containing the component of the (meth)acrylic acid urethane (C) represented by the above formula (3), as an interface TEGO Rad 2200N (trade name, manufactured by Evonik Degussa Japan Co., Ltd.) of the active agent (D) and Irgacure 754 (trade name, manufactured by BASF Japan) as a photopolymerization initiator (E) were mixed to obtain uniformity. After the solution, a membrane filter (pore size: 0.2 μm) made of polytetrafluoroethylene (PTFE) was used for filtration to obtain a filtrate (photocurable inkjet ink 1).

The viscosity of the ink 1 at 25 ° C was measured using an E-type rotational viscometer (TV-22 (trade name) manufactured by Toki Sangyo Co., Ltd., the same below), and the result was 6.1 mPa. s.

[Example 2]

In Example 1, as the (meth) acrylate (B), Blemmer GMR (trade name, glycerin dimethacrylate, manufactured by Nippon Oil Co., Ltd.) was used instead of 4-hydroxybutyl acrylate, and it was used as IRR214-K (trade name, tricyclodecane dimethanol diacrylate, manufactured by Daicel Cytec Co., Ltd.) of (meth) acrylate (F), and the amount of blending is changed as follows, and The photocurable inkjet ink 2 of the following composition was prepared in the same manner.

The viscosity of the ink 2 at 25 ° C was measured and found to be 5.6 mPa. s.

[Example 3]

In Example 2, light of the following composition was prepared in the same manner as in Example 2 except that 4-methyl butyl acrylate was used as the (meth) acrylate (B) instead of Blemmer GMR (trade name). Curable inkjet ink 3.

The viscosity of the ink 3 at 25 ° C was measured and found to be 5.4 mPa. s.

[Example 4]

In the example 2, as the (meth) acrylate (B), 1,4-cyclohexane dimethanol monoacrylate (manufactured by Nippon Kasei Co., Ltd.) was used instead of Blemmer GMR (trade name), and A photocurable inkjet ink 4 of the following composition was prepared in the same manner as in Example 2.

The viscosity of the ink 4 at 25 ° C was measured and found to be 5.8 mPa. s.

[Example 5]

In Example 3, DAROCUR MBF (trade name, manufactured by BASF Japan) was used instead of Irgacure 754 (trade name) as the photopolymerization initiator (E), and the blending amount was changed as described below. A photocurable inkjet ink 5 of the following composition was prepared in the same manner as in Example 3.

The viscosity of the ink 5 at 25 ° C was measured and found to be 5.4 mPa. s.

[Example 6]

In Example 3, as (meth) acrylate (F), Aronix M-208 (trade name, bisphenol F ethylene oxide modified (n) was used. 2) The photocuring property of the following composition was prepared in the same manner as in Example 3 except that the diacrylate (manufactured by the East Asia Synthetic Co., Ltd.) was used instead of the IRR214-K (trade name), and the blending amount was changed as described below. Inkjet ink 6.

The viscosity of the ink 6 at 25 ° C was measured and found to be 5.8 mPa. s.

[Comparative Example 1]

In the example 2, the ink 7 of the following composition was prepared in the same manner as in Example 2 except that the (meth) acrylate (B) was not used and the amount of the formulation was changed as described below.

The viscosity of the ink 7 at 25 ° C was measured and found to be 5.8 mPa. s.

[Comparative Example 2]

In Example 2, Aronix M-305 (trade name, pentaerythritol triacrylate, manufactured by Toagosei Co., Ltd.) as a trifunctional acrylate having a hydroxyl group was used instead of (meth)acrylate (B), and as follows An ink 8 of the following composition was prepared in the same manner as in Example 1 except that the blending amount was changed as described above.

The viscosity of the ink 8 at 25 ° C was measured and found to be 6.0 mPa. s.

<Evaluation of Ink 1 to Ink 8>

The following evaluations were performed on the inks 1 to 8 prepared in the above manner.

(Formation of surface liquid-repellent hardening film)

A 4 cm square acrylic substrate (manufactured by Asahi Kasei Technoplus Co., Ltd., Delaglas AD 999 (trade name)) and a glass substrate were prepared. The ink 1 was injected into an ink cartridge, and then mounted on an ink jet apparatus (DMP-2831 (trade name) manufactured by FUJIFILM Dimatix Inc.) at a discharge voltage (piezoelectric voltage) of 16 V, and the head temperature was The ink 1 was applied to the entire surface of each substrate under the discharge conditions of 30 ° C, a driving frequency of 5 kHz, and a coating number of one time, and the printing resolution was set to 1250 dpi. Thereafter, the substrate was irradiated with ultraviolet rays at a UV exposure amount of 2,000 mJ/cm ² using a UV irradiation device (J-CURE 1500 (trade name) manufactured by Jatec Co., Ltd.), whereby the ink 1 was photocured, thereby obtaining An acrylic resin substrate and a glass substrate having a surface liquid-repellent cured film formed thereon. Further, a substrate on which the surface liquid-repellent cured film is formed is also obtained for the ink 2 to the ink 8 in the same manner.

Further, a microlens is formed on the acrylic resin substrate on which the surface liquid-repellent cured film is formed as follows.

(formation of microlenses)

The photo-curable composition (L1) of the microlens was injected into an ink cartridge, and then mounted on an inkjet apparatus (DMP-2831 (trade name) manufactured by FUJIFILM Dimatix Inc.) at a discharge voltage (piezoelectric voltage). The film resolution was set to 512 dpi and the photorefractive composition of the microlens was 50 μm at a discharge interval of 22 V, an ink jet head temperature of 34 ° C, a driving frequency of 5 kHz, and a coating number of one. The object (L1) is applied to the acrylic resin substrate on which the surface liquid repellent film is formed (on the surface liquid-repellent cured film) in a dot pattern. Thereafter, the substrate was irradiated with ultraviolet rays at a UV exposure amount of 1,000 mJ/cm ² using a UV irradiation device (J-CURE 1500 (trade name) manufactured by Jatec Co., Ltd.), whereby an acrylic resin substrate on which microlenses were formed was obtained. .

Further, the photocurable composition (L1) for microlenses was prepared by mixing Aronix M-305 (trade name, 3.5 g), tetrahydrofurfuryl acrylate (3.5 g), and Irgacure 754 (trade name, 0.49 g). After obtaining a uniform solution, the filtrate obtained by filtration using a membrane filter made of PTFE (pore size: 0.2 μm) has a viscosity of 16.8 mPa at 25 ° C. s.

(film thickness of surface liquid-repellent cured film)

On a glass substrate on which a surface-repellent hardening film was formed, a part of the cured film was cut off with a cutter, and then a stylus type film thickness meter P-15 (trade name, manufactured by KLA-Tencor Japan Co., Ltd.) was used. The step thickness was measured to determine the film thickness of the surface liquid-repellent cured film.

The case where the film thickness is less than 1 μm is ○, and the case where the film thickness is 1 μm or more is ×. The results are shown in Table 1.

(Transparency of surface liquid-repellent cured film)

The transmittance of the cured film at 400 nm was measured by a UV-visible near-infrared spectrophotometer V-670 (trade name, manufactured by JEOL Ltd.) on a glass substrate on which a surface liquid-repellent cured film was formed. Chromaticity (b ^* ) at 380 nm to 780 nm.

The chromaticity (b ^* ) is an index indicating a yellow hue, and if the value becomes large, it indicates that it is further colored yellow. The chromaticity (b ^* ) is preferably less than 0.1.

(evaluation of adhesion)

On a microlens-forming surface of an acrylic resin substrate on which a microlens is formed, a 18 mm wide Scotch transparent adhesive tape is used to form a transparent color _TM 600 (trade name, manufactured by 3M), and then a microlens is formed toward the substrate. The surface was pulled at a 90-degree angle to peel off the tape, and the substrate after the tape was peeled off was observed.

When the surface liquid-repellent cured film and the microlens were free from abnormalities (no peeling was observed), the case where the surface liquid-repellent cured film or a part of the microlens was peeled off was set to ×.

Further, the acrylic resin substrate on which the microlenses were formed was subjected to a high-temperature and high-humidity test (standing at a temperature of 50 ° C and a humidity of 90% for 100 hours), and the same adhesion evaluation was performed.

(Evaluation of microlens diameter (D))

The diameter (D) of the microlens formed on the acrylic resin substrate was measured using an optical microscope BX51 (trade name, manufactured by OLYMPUS Co., Ltd.). The value of the microlens diameter is the average of the measurements of the three sites.

(Evaluation of microlens height (H))

The height (H) of the microlens formed on the acrylic resin substrate was measured in a 3D mode using a stylus type film thickness meter P-15, and the average value thereof was calculated. The value of the microlens height is the average of the measurements of the three sites.

(Evaluation of H/D)

According to the diameter (D) and the height (H) of the microlens obtained in the above manner, H/D is obtained by calculation.

The results of these are shown in Table 1.

It is understood that the inks of Examples 1 to 6 are more excellent in adhesion to the acrylic resin substrate than the inks of Comparative Examples 1 and 2. Further, the surface liquid-repellent cured film obtained from the inks of Examples 1 to 6 was not easily colored (yellow), and was excellent in transparency and liquid repellency. When a microlens was formed on the cured film, the height/diameter was 0.2. the above. Therefore, the ink of the present invention can be preferably used for the manufacture of a light guide plate for a high-quality image display device or the like.

[Industrial availability]

As described above, the ink of the present invention is useful for producing high quality optical parts.

Claims (17)

A photocurable inkjet ink comprising an organic solvent (A), a difunctional or lower (meth) acrylate having a hydroxyl group (B), a (meth) acrylate (C), a surfactant (D) and the photopolymerization initiator (E), and the content of the solvent (A) is 40% by weight to 98% by weight based on 100% by weight of the photocurable inkjet ink. The photocurable inkjet ink according to the above aspect of the invention, wherein the (meth) acrylate (B) is a compound selected from the group consisting of the following formula (1), glycerol mono(meth)acrylate At least one compound selected from the group consisting of glycerol di(meth)acrylate and 2-hydroxy-3-propenyl-oxypropyl (meth)acrylate, (In the formula (1), n R ^a are each independently an alkylene group having a ring structure of 2 to 12 carbon atoms, R ^b is an alkyl group having 1 to 6 carbon atoms or hydrogen, and n is 1~ An integer of 30). The photocurable inkjet ink according to claim 1, wherein the (meth) acrylate (B) is selected from the group consisting of 2-hydroxyethyl (meth) acrylate and (meth) acrylate-2. -hydroxypropyl ester, (meth)acrylic acid-3-hydroxyl Propyl propyl ester, 2-hydroxybutyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate and 1,4-cyclohexane dimethanol At least one compound in the group consisting of (meth) acrylate. The photocurable inkjet ink according to the above aspect of the invention, wherein the (meth)acrylic acid urethane (C) is a compound represented by the following formula (2), (In the formula (2), R ¹ , R ² and R ³ each independently represent a divalent organic group having 1 to 20 carbon atoms, and R ⁴ and R ⁵ are each independently hydrogen or an alkyl group having 1 to 6 carbon atoms; , m and n are each independently an integer of 1 to 3). The photocurable inkjet ink according to claim 4, wherein R ¹ and R ³ in the above formula (2) are each independently an alkylene group having a carbon number of 1 to 10, and R ² is selected from the group consisting of a divalent group in the group (a), The photocurable inkjet ink according to claim 1, further comprising (meth) acrylate (B) and (meth) acrylate (C) other than (meth) acrylate (C) Acrylate (F). The photocurable inkjet ink according to claim 1, wherein the surfactant (D) is at least one selected from the group consisting of a fluorine-based surfactant and an anthrone-based surfactant. Compound. The photocurable inkjet ink according to claim 1, wherein the surfactant (D) is a compound having at least one reactive group. The photocurable inkjet ink according to claim 8, wherein the reactive group of the surfactant (D) is selected from the group consisting of (meth) acrylonitrile, epoxy and oxetanyl At least 1 base in the group consisting. Photocurable inkjet ink as claimed in claim 1 Water, wherein the above solvent (A) is an organic solvent having a boiling point of from 100 ° C to 300 ° C. The photocurable inkjet ink according to claim 1, wherein the solvent (A) is a compound having a hydroxyl group. The photocurable inkjet ink according to claim 1, wherein the viscosity at 25 ° C is 1.0 mPa. s~30 mPa. s. A surface liquid-repellent cured film obtained by curing the photo-curable inkjet ink according to any one of claims 1 to 12. A microlens formed on a surface liquid-repellent cured film according to claim 13 of the patent application by an inkjet method. A method of forming a microlens, comprising the step of forming a microlens on a surface liquid-repellent cured film according to claim 13 of the patent application by an inkjet method. An optical component comprising the microlens of claim 14 of the patent application. An image display device comprising the optical component of claim 16 of the patent application.