KR20170139600A - A photocurable resin composition, a process for producing a cured film using the same, and a laminate including the cured film - Google Patents

Abstract

(Meth) acrylate having two or more functional groups, a polyrotaxane, silica particles, and a photopolymerization initiator,
(1) to (4), when the content of the polyfunctional (meth) acrylate is X parts by mass, the content of the polyrotaxane is Y parts by mass and the content of the silica particles is Z parts by mass Wherein the photo-curable resin composition satisfies the following conditions.
(1): X + Y + Z = 100
Equation (2): X? 50
(3): 3? Y? 20
Equation (4): 25? Z? 40

Description

A photocurable resin composition, a process for producing a cured film using the same, and a laminate including the cured film

The present invention relates to a photo-curing resin composition, a process for producing a cured film using the same, and a laminate including the cured film.

As a photocurable resin composition for forming a hard coating layer on a transparent base film, for example, a photocurable resin composition comprising a bifunctional or higher polyfunctional (meth) acrylate and a polyrotaxane and a photopolymerization initiator is known (Patent Document 1).

Japanese Patent Application Laid-Open No. 2009-204725

In the photo-curing resin composition described in Patent Document 1, the surface hardness (pencil hardness) of the resulting cured film is not necessarily sufficiently satisfactory.

The present invention includes the inventions described in the following [1] to [5].

(1) A photopolymerizable composition comprising a polyfunctional (meth) acrylate having at least two functional groups, a polyrotaxane, silica particles and a photopolymerization initiator, wherein the content of the polyfunctional (meth) acrylate is X parts by mass, Satisfies the following expressions (1) to (4) when the content is Y mass part and the content of the silica particles is Z mass part.

(1): X + Y + Z = 100

Equation (2): X? 50

(3): 3? Y? 20

Equation (4): 25? Z? 40

[2] The photocurable resin composition according to [1], wherein the polyrotaxane has a (meth) acryloyl group.

[3] A process for producing a cured film, comprising the step of applying the photo-curable resin composition according to [1] or [2] on a substrate to obtain a composition layer, and a step of exposing the composition layer to cure the composition layer.

[4] A laminate comprising a substrate and a cured film laminated on at least one side of the substrate, wherein the cured film comprises a cured product of the photo-curable resin composition according to [1] or [2].

[5] A laminate according to [4], wherein the substrate has a multilayer structure.

[6] A laminate according to [4] or [5], wherein the substrate comprises a (meth) acrylic resin.

[7] A display device comprising a laminate according to [5] or [6].

When the photo-curable resin composition of the present invention is used, a cured film having sufficient surface hardness and excellent appearance can be obtained.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a cross-sectional view schematically showing a layer constitution example of a laminate. FIG.
2 is a cross-sectional view schematically showing a first layer constitution example of a display device.
3 is a cross-sectional view schematically showing a second layer constitution example of the display device.

Hereinafter, a preferred embodiment of the present invention will be described in detail. In the present specification, the term "(meth) acrylate" refers to the generic name of acrylate and methacrylate, and the term "(meth) acryloyl group" refers to the generic name of acryloyl group and methacryloyl group, Resin " refers to the generic name of an acrylic resin and a methacrylic resin.

[Photocurable resin composition]

The photo-curing resin composition of the present embodiment contains a polyfunctional (meth) acrylate having two or more functional groups, a polyrotaxane, silica particles, and a photopolymerization initiator.

Examples of the bifunctional or higher polyfunctional (meth) acrylate include 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) Acrylates such as ethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, dipropylene glycol di , Diethylene glycol bis [beta] - (meth) acryloyloxypropionate, trimethylol ethane tri (meth) acrylate, trimethylol propane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (Meth) acrylate, tri (2-hydroxyethyl) isocyanate di (meth) acrylate, pentaerythritol tetra (meth) acrylate, 2,3-bis (meth) acryloyloxyethyloxymethyl [ ] (Meth) acrylates such as heptane, poly 1,2-butadiene di (meth) acrylate, 1,2-bis (meth) acryloyloxymethyl hexane, nonaethylene glycol di (meth) acrylate, tetradecane ethylene glycol di Bis (meth) acryloyloxymethyl tricyclo [5.2.10] decane, hydrogenated bisphenol A di (meth) acrylate, 2,2-bis (Meth) acryloyloxyethoxyphenyl) propane, 1,4-bis ((meth) acryloyloxymethyl) cyclohexane, hydroxypivalic acid ester neopentyl glycol di (meth) acrylate, bisphenol A Diglycidyl ether di (meth) acrylate, and epoxy-modified bisphenol A di (meth) acrylate.

≪ Polylotaxan >

The polyrotaxane is a polyrotaxane which has openings of a plurality of ring-shaped molecules skewered by linear molecules, and both ends of a similar polyrotaxane in which a plurality of cyclic molecules are enclosed in a linear molecule (Both ends of the linear molecule), a block group is arranged so that the cyclic molecule is not liberated.

(Linear molecule)

The straight chain molecule contained in the polyrotaxane is a molecule or substance which is embedded in the cyclic molecule and can be ununohydrobondically integrated, and is not particularly limited as long as it is a straight chain. In the present specification, the term " linear molecule " refers to a molecule including a polymer and all other materials that satisfy the above requirements. In the present specification, the term "linear chain" of "linear molecule" means substantially "linear chain". That is, when the cyclic molecule, which is a rotor, is rotatable, or the cyclic molecule is slidable or movable on the linear molecule, the linear molecule may have a branched chain. The length of the " linear chain " is not particularly limited as long as the cyclic molecule can slide or move on the linear molecule.

As the linear molecule, for example, Polyvinyl alcohol, polyvinyl pyrrolidone, poly (meth) acrylic acid, cellulose resin (carboxymethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose and the like), polyacrylamide, polyethylene oxide, polyethylene glycol, polyvinyl acetal Hydrophilic polymers such as resin, polyvinyl methyl ether, polyamine, polyethyleneimine, casein, gelatin, starch, and copolymers thereof; (Polystyrene, acrylonitrile-styrene copolymer resin, etc.), acrylic resin (such as polymethyl methacrylate), polyolefin resin (polyethylene, polypropylene and other copolymer resins with olefinic monomers), polyester resin, polyvinyl chloride resin, polystyrene resin (Meth) acrylate copolymer, acrylonitrile-methyl acrylate copolymer resin, etc.), hydrophobic polymers such as polycarbonate resin, polyurethane resin, vinyl chloride-vinyl acetate copolymer resin and polyvinyl butyral resin; And derivatives or modified products thereof.

Among the hydrophilic polymers, polyethylene glycol, polypropylene glycol, and copolymers of polyethylene glycol and polypropylene glycol are preferred. Among the hydrophobic polymers, polyisoprene, polyisobutylene, polybutadiene, polytetrahydrofuran, polydimethylsiloxane, polyethylene and polypropylene are preferred. As the linear molecule, a hydrophilic polymer is more preferable, and polyethylene glycol is more preferable.

The linear molecule has a molecular weight of 1,000 or more, such as 1,000 to 1,000,000, preferably 5,000 or more, such as 5,000 to 1,000,000 or 5,000 to 500,000, more preferably 10,000 or more, such as 10,000 to 1,000,000, 500,000 or 10,000 to 300,000. In addition, when the straight-chain molecule is a biodegradable molecule, the load on the environment is small, and it is preferable from the viewpoint of being "eco-logical".

It is preferable that the linear molecule has a reactor at both ends thereof. By having this reactor, it is possible to easily react with the block group. The reactor depends on a block group to be used, and examples thereof include a hydroxyl group, an amino group, a carboxyl group and a thiol group.

(Cyclic molecule)

Any cyclic molecule can be used as long as the cyclic molecule can encapsulate the linear molecule.

In the present specification, the term " cyclic molecule " refers to various cyclic molecules including cyclic molecules. In the present specification, the term " cyclic molecule " refers to a molecule or substance that is substantially cyclic. In other words, the phrase " substantially phantom " means that the word " C " is not completely closed, such as " C " It is also meant to include having. In addition, the ring to the "bicyclo molecule" to be described later can also be defined in the same way as "substantially cyclic" of "cyclic molecule". In other words, one ring or both rings of the " bicyclo molecule " may be a ring that is not completely ring closed, such as " C " Structure.

Examples of the cyclic molecule include various cyclodextrins (for example,? -Cyclodextrin,? -Cyclodextrin,? -Cyclodextrin, dimethylcyclodextrin and glucocododecyldextrin, derivatives or modified products thereof, etc.) Ethers, benzo crown, dibenzo crown and dicyclohexanone crown, and derivatives or modified products thereof.

The above-mentioned cyclodextrins, crown ethers and the like have different sizes of the opening portions of the cyclic molecules depending on their types. Therefore, when the type of the linear molecule to be used, specifically, the linear molecule used is determined to be a cylindrical shape, the cyclic molecule to be used can be selected depending on the diameter of the cross-section of the cylindrical shape, the hydrophobicity or hydrophilicity of the linear molecule, Further, in the case of using a linear molecule having a relatively large diameter and a relatively small diameter of an annular molecule having a relatively large opening, two or more linear molecules may be encapsulated in the opening of the cyclic molecule. Of these, cyclodextrins are biodegradable, and thus are preferred from the viewpoint of being environmentally friendly.

It is preferable to use alpha -cyclodextrin as the cyclic molecule.

When the cyclic molecule is cyclodextrin, the number (cyclic amount) of the cyclic molecule encapsulating the linear molecule is preferably 0.05 to 0.60, more preferably 0.10 to 0.50, and more preferably 0.20 to 0.40 Is more preferable. If it is less than 0.05, the pulley effect may not be exhibited. If it exceeds 0.60, the cyclodextrin, which is a cyclic molecule, may be arranged too tightly to lower the movability of the cyclodextrin, and the cost of the organic solvent of the cyclodextrin itself The solubility of the resulting polyrotaxane in an organic solvent may be lowered.

It is preferred that the cyclic molecule has a reactor outside the ring. When the cyclic molecules are bonded or crosslinked to each other, the reaction can be easily carried out using this reactor. The reactor is also dependent on the crosslinking agent and the like to be used, and examples thereof include a hydroxyl group, an amino group, a carboxyl group, a thiol group and an aldehyde group. It is also preferable to use a group which does not react with the block group at the time of the reaction (blocking reaction) between the linear molecule and the blocking group.

 (Block group)

The block group may be any group as far as the cyclic molecule is a group that retains a skewed shape by the linear molecule. Examples of such groups include groups having a " large volume " and / or groups having " ionic ". Here, the term " group " means various groups including a polar group and a polymer group. Further, the "ionic" of the group having "ionic" and the "ionic" possessed by the cyclic molecule mutually affect each other, for example, by repelling each other, whereby the cyclic molecule becomes a skewer- Can be seen.

The block group may be a main chain or a side chain of the polymer as long as it has a skewer shape as described above. In the case where the block group is the polymer A, the polymer A may be present as a matrix and the compound (polyrotaxane) according to the present embodiment may be contained in a part thereof. Conversely, a compound related to the present embodiment may be contained as a matrix. May be included. Thus, by combining with the polymer A having various properties, a composite material having a combination of the characteristics of the compound related to the present embodiment and the characteristics of the polymer A can be formed.

Specific examples of the block copolymer of the present invention include block copolymers of a dinitrophenyl group such as a 2,4-dinitrophenyl group and a 3,5-dinitrophenyl group, a cyclodextrin group, an adamantane group, a trityl group, Pyrenes, and derivatives or modified products thereof. More specifically, for example, as a block group in the case of using alpha -cyclodextrin as the cyclic molecule and polyethylene glycol as the linear molecule, a cyclodextrin, a 2,4-dinitrophenyl group, a 3,5-dinitrophenyl group , Adamantane gas streams, trityl gas streams, fluororesins and pyrenes, and derivatives or modified products thereof.

Next, modified polyrotaxane which can be preferably used in the photo-curable resin composition of the present embodiment will be described. In the present embodiment, polyrotaxane having a plurality of modifications described below in combination is preferably used.

≪ Crosslinked polyrotaxane >

The crosslinked polyrotaxane refers to a compound in which two or more polyrotaxanes are chemically bonded to each other and the two cyclic molecules may be the same or different. In this case, the chemical bond may be a simple bond or a bond containing various atoms or molecules.

Also, a " bicyclo molecule " having a molecule having a cyclic ring structure, that is, a first and a second ring can be used. In this case, for example, a cross-linked polyrotaxane can be obtained by mixing a "bicyclo molecule" with a straight-chain molecule and skewing the straight-chain molecule in the first and second rings of the "bicyclo molecule" .

This crosslinked polyrotaxane has viscoelasticity because the cyclic molecule penetrating the straight chain molecule in a skewered manner can move along the straight line (pulley effect), and even if the tension is applied, the tension due to the shearing effect It is possible to disperse them uniformly and to relax the internal stress.

≪ Hydrophobic formula polyrotaxane >

When the cyclic molecule of polyrotaxane is a cyclodextrin such as alpha -cyclodextrin, the hydrophobic modified polyrotaxane in which at least one of the hydroxyl groups of the cyclodextrin is replaced by another organic group (hydrophobic group) in the present embodiment, Since the solubility in a solvent contained in the solvent is improved.

Specific examples of the hydrophobic group include, for example, an alkyl group, a benzyl group, a benzene derivative-containing group, an acyl group, a silyl group, a trityl group, a nitrate ester group, a tosyl group, an alkyl-substituted ethylenic unsaturated group as a photo- Alkyl-substituted epoxy groups, and the like, but are not limited thereto. In the above hydrophobic-modified polyrotaxane, one of the above-mentioned hydrophobic groups may be used alone or two or more of them may be used in combination.

When the maximum number by which the hydroxyl group of the cyclodextrin can be modified is 1, it is preferably 0.02 or more, more preferably 0.04 or more, and still more preferably 0.06 or more.

If it is less than 0.02, solubility in an organic solvent is not sufficient, and insoluble water (protruding portion derived from foreign matter adhesion, etc.) may be produced.

Here, the maximum number of the hydroxyl groups of the cyclodextrin to which the cyclodextrin can be modified is in other words, the total number of the hydroxyl groups contained in the cyclodextrin before the modification. The formula is, in other words, the ratio of the modified number of hydroxyl groups to the total number of hydroxyl groups.

In addition, at least one of the hydrophobic groups may be present, but in this case, it is preferable that the hydrophobic group has one hydrophobic group per one cyclodextrin ring. Further, by introducing a hydrophobic group having a functional group, the reactivity with other polymers can be improved.

≪ Polyroctic acid having an unsaturated double bond >

It is possible to introduce an unsaturated bonding group into a substantial portion of the cyclic molecule. By the introduction of this group, polymerization with the polymerizable compound becomes possible.

The introduction of the unsaturated bond group can be carried out, for example, by substituting at least part of the cyclic molecule having a hydroxyl group (-OH) such as cyclodextrin with an unsaturated bond group, preferably an unsaturated double bond group.

Examples of the unsaturated bond group, such as an unsaturated double bond group, include an olefinyl group (a group having an olefinic double bond), and examples thereof include an acryl group, a (meth) acryloyl group, a vinyl ether group, But is not limited thereto.

As the introduction of the unsaturated double bond group, the following method can be used. That is, a method by carbamate bond formation by an isocyanate compound or the like; A method by formation of an ester bond with a carboxylic acid compound, an acid chloride compound or an acid anhydride; A method by formation of a silyl ether bond by a silane compound or the like; And a method of forming a carbonate bond by a chlorocarbonic acid compound or the like.

When a (meth) acryloyl group is introduced as an unsaturated double bond group via a carbamoyl bond, the polyrotaxane is dissolved in a dehydrating solvent such as DMSO or DMF, and a (meth) acryloyl reagent having an isocyanate group is added . In addition, when introduced via an ether bond or an ester bond, a (meth) acryloyl reagent having an active group such as a glycidyl group or an acid chloride may be used.

The step of replacing the hydroxyl group of the cyclic molecule with the unsaturated double bond group may be carried out before or after the step of preparing the similar polyrotaxane. Further, the polyrotaxane may be blocked before or after the step of preparing the polyrotaxane by blocking the polyrotaxane. In addition, when the polyrotaxane is a crosslinked polyrotaxane, the polyrotaxane may be crosslinked before, during or after the step of crosslinking the polyrotaxanes. Or may be provided in two or more of these periods. The substitution step is preferably carried out after the polyrotaxane is prepared by blocking the polyrotaxane to form a polyrotaxane. The conditions used in the substitution process depend on the substituted unsaturated double bond group, but are not particularly limited and various reaction methods and reaction conditions can be used.

The polyrotaxane used in the present embodiment is preferably a hydrophobic modified polyrotaxane, more preferably a polyrotaxane having an unsaturated double bond, and more preferably a polyrotaxane having a (meth) acryloyl group.

Examples of the polyrotaxane having such a (meth) acryloyl group include SeRM (registered trademark) key mixers SM3400C, SA3400C and SA2400C manufactured by Advance Soft Materials Co., Ltd.

<Silica Particle>

As the silica particles, powdery silica or organosilica sol in which silica particles are dispersed in a solvent can be used. These silica particles are commercially available.

Examples of the powdery silica include Aerosil (registered trademark) 130, Aerosil (registered trademark) 300, Aerosil (registered trademark) 380, Aerosil (registered trademark) TT600, Aerosil (Manufactured by Nippon Aerosil Co., Ltd.), SYLYSIA 470 (manufactured by Fuji Silysia Co., Ltd.) and SG Flake (manufactured by Nippon Sheet Glass Co., Ltd.).

Examples of the organosilica sol include isopropyl alcohol-dispersed silica sol (IPA-ST, IPA-ST-L, IPA-ST- ST-ZL), dimethyl acetamide-dispersed silica sol (DMAC-ST, DMAC-ST-ZL), ethylene glycol-dispersed silica sol (EG-ST, , Propylene glycol monomethyl ether dispersed silica sol (PGM-ST), ethyl acetate dispersed silica sol (EAC-ST), propylene glycol monomethyl ether acetate (NPC-ST-30), ethylene glycol mono n-propyl ether dispersion silica sol MEK-ST-L, MEK-ST-ZL, MEK-ST-UP, MEK-AC-2104Z, (MIBK-ST, MIBK-ST-L, MIBK-SD and MIBK-SD-L) (hereinafter referred to as &quot; MEK-AC-2130Y, MEK- (Manufactured by Nissan Chemical Industries, Ltd.) and OSCAL (registered trademark) series (manufactured by Nikkiso Catalysts Co., Ltd.).

The average particle size of the silica particles is preferably 100 nm or less, more preferably 30 nm or less. If the average primary particle diameter exceeds 100 nm, the transparency of the obtained coating film tends to be impaired.

In the present specification, the average primary particle diameter of the silica particles represents a value measured by the JIS Z 8828 dynamic light scattering method.

The photo-curable resin composition of the present embodiment has a structure in which the content of polyfunctional (meth) acrylate having two or more functional groups is X parts by mass, the content of polyrotaxane is Y parts by mass, and the content of silica particles is Z parts by mass, 1) to (4).

(1): X + Y + Z = 100

Equation (2): X? 50

(3): 3? Y? 20

Equation (4): 25? Z? 40

The formula (1) and the formula (2) show that the content of the polyfunctional (meth) acrylate having two or more functional groups is 50 (meth) acrylate based on the total 100 parts by mass of the bifunctional or more polyfunctional (meth) acrylate and the polyrotaxane and the silica particles. Mass part or more. As X becomes smaller than 50, the surface hardness of the resulting cured film tends to decrease. X is preferably 70 or less. It is more preferable that the formula (2) is the formula (2 '). More preferably, X is greater than 50.

(2 '): 50? X? 70

The content of the polyrotaxane is 3 parts by mass or more and 20 parts by mass or less per 100 parts by mass of the total of the polyfunctional (meth) acrylate and the polyrotaxane and the silica particles, Or less. As Y becomes smaller than 3, cracks tend to occur in the resulting cured film, and appearance tends to be damaged. As Y becomes larger than 20, the surface hardness of the resulting cured film tends to decrease. The formula (3) is preferably the formula (3 ').

Formula (3 '): 5? Y? 15

The formulas (1) and (4) show that the silica particles are contained in an amount of 25 parts by mass or more and 40 parts by mass or less based on 100 parts by mass of the total amount of the polyfunctional (meth) acrylate and the polyrotaxane and the silica particles . As Z becomes smaller than 25, the surface hardness of the resulting cured film tends to decrease. As Z becomes larger than 40, cracks tend to occur in the resulting cured film, and appearance tends to be damaged. The formula (4) is preferably the formula (4 ').

Equation (4 '): 25 < Z < 40

<Photopolymerization initiator>

As the photopolymerization initiator, a polymerization initiator capable of exhibiting photopolymerization initiating ability by light irradiation in the presence of an ultraviolet absorber is preferable, and examples thereof include acetophenone, acetophenone benzylketal, anthraquinone, 1- (4-isopropylphenyl 2-methylpropane-1-one, carbazole, xanthone, 4-chlorobenzophenone, 4,4'-diaminobenzophenone, 1,1- dimethoxydeoxybenzoin, Dimethyl-4-methoxybenzophenone, thioxanthone, 2,2-dimethoxy-2-phenylacetophenone, 1- (4-dodecylphenyl) -2-hydroxy- Methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1-one, triphenylamine, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 1- Hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, fluorene, fluorene, benzaldehyde, benzoin ethyl ether, benzoisopropyl ether, benzophenone, , 3-methylaceto Phenanone, 3,3 ', 4,4'-tetra-tert-butylperoxycarbonylbenzophenone (BTTB), 2- (dimethylamino) -1- [4- (morpholinyl) Phenylmethyl) -1-butanone, 4-benzoyl-4'-methyldiphenylsulfide, benzyl and the like.

The content of the photopolymerization initiator is preferably 1 to 15 parts by mass, more preferably 2 to 10 parts by mass, based on 100 parts by mass of the sum of the bifunctional or higher functional polyfunctional (meth) acrylate and the polyrotaxane and the silica particles . If the content of the photopolymerization initiator is larger than the above range, a photopolymerization initiator which is not used for photopolymerization initiation may remain, which may cause harmful effects such as lowering of the visible light transmittance. On the other hand, when the amount is smaller than the above range, the ability to initiate photopolymerization is not sufficiently exhibited, which may result in insufficient curing of the ultraviolet curable resin.

<Other ingredients>

The photo-curing resin composition of the present embodiment may further contain an antistatic agent. As such an antistatic agent, metal oxides and metal salts are preferable. Examples of the metal oxide include ITO (indium-tin composite oxide), ATO (antimony-tin composite oxide), tin oxide, antimony pentoxide, zinc oxide, zirconium oxide, titanium oxide and aluminum oxide. Examples of the metal salt include zinc antimonate and the like. The content of the antistatic agent is preferably 1 to 100 parts by mass per 100 parts by mass of the total amount of the bifunctional or higher functional (meth) acrylate, polyrotaxane, silica particles and photopolymerization initiator, to be. When the content of the antistatic agent is larger than the above range, the ultraviolet curing property of the photocurable resin composition is impaired or the visible light transmittance of the resulting cured film tends to be lowered. The antistatic agent preferably has a particle diameter of 0.001 to 0.1 mu m. If the particle diameter is too small, industrial production is difficult, and if the particle diameter is too large, the transparency of the resulting cured film tends to decrease.

The photo-curing resin composition of the present embodiment may contain an additive such as an ultraviolet absorber, an antioxidant, a colorant, a fluorine additive for imparting water-repellent or oil-repellent performance, and a leveling agent, if necessary. By including the leveling agent, the smoothness and scratch resistance of the cured coating can be increased.

The photo-curing resin composition of the present embodiment preferably further contains a solvent in that it is provided in a coating step to be described later. Examples of such a solvent include alcohols such as methanol, ethanol, 1-propanol, 2-propanol (isopropyl alcohol), 1-butanol, 2-butanol (sec-butyl alcohol) , 2-methyl-2-propanol (tert-butyl alcohol); Alkoxy alcohol solvents such as 2-ethoxyethanol, 2-butoxyethanol, 3-methoxy-1-propanol, 1-methoxy-2-propanol and 1-ethoxy-2-propanol; Ketol solvents such as diacetone alcohol; Ketone solvents such as acetone, methyl ethyl ketone and methyl isobutyl ketone; Aromatic hydrocarbon solvents such as toluene and xylene; And ester solvents such as ethyl acetate and butyl acetate.

The content of the solvent is preferably 20 to 10000 parts by mass based on 100 parts by mass of the total amount of the bifunctional or higher functional (meth) acrylate, polyrotaxane, silica particles and photopolymerization initiator.

&Lt; Preparation of photocurable resin composition >

The photo-curing resin composition of the present embodiment is obtained by mixing a polyfunctional (meth) acrylate having two or more functional groups, a polyrotaxane, silica particles, a photopolymerization initiator and, if necessary, a solvent, an antistatic agent and other additives , The order of mixing thereof, and the like are not particularly limited.

[Process for producing a cured film]

Next, a method for producing a cured film using the photo-curable resin composition of the present embodiment will be described. The production method of the cured film includes the following steps (1) and (2).

(1) a step of applying the above-mentioned photo-curing resin composition onto a substrate to obtain a composition layer

(2) a step of curing the composition layer by exposure to the composition layer

&Lt; Process (1) >

Examples of the resin constituting the base material include (meth) acrylic resins, polyester resins, polycarbonate resins, polycyclic olefin resins, polystyrene resins, methacryl-styrene copolymers (MS resins), acrylonitrile- Resin), polyvinylidene fluoride resin (PVDF resin), and the like. Among them, the (meth) acrylic resin is preferable because it is easy to provide a cured film having high transparency, high surface hardness and high scratch resistance. Methacrylic resin is more preferable.

The thickness of the substrate is preferably 30 to 300 mu m, more preferably 50 to 200 mu m. When the thickness is thinner than the above range, there is a possibility that the strength of the obtained laminated product of the cured film and the substrate can not be maintained. On the other hand, if it is thicker than the above-mentioned range, the transparency of the base material is lowered and the bending property is lowered. The base material may contain various additives. Such additives include, for example, stabilizers, plasticizers, lubricants, and flame retardants.

The base material may have a flat surface such as a normal sheet or film, or may have a curved surface such as a convex lens or a concave lens. Further, a fine structure such as a small unevenness may be provided on the surface.

The base material may be colored with a dye or a pigment as necessary, or may contain an antioxidant, an ultraviolet absorber, rubber particles, or the like. The thickness of the resin base material is preferably 0.1 mm or more, and more preferably 3.0 mm or less.

The base material may be a single layer or a multilayer structure. As the resin substrate having a multilayer structure, it is preferable that a (meth) acrylic resin layer is laminated on at least one surface of the main resin layer. As the base material of the multilayer structure, an optical laminate including a polarizing plate, a retarder, and the like is also preferable.

The substrate may be in the form of a sheet, a film, a multilayer structure, or the like, and the surface of the substrate may be planar or curved.

The substrate may have an adhesive layer on its surface. The adhesive layer is for adhering the cured film to the substrate and is formed according to a conventional method. The adhesive for forming the adhesive layer is appropriately selected depending on the material of the substrate and the cured film, and for example, an acrylic adhesive (pressure sensitive adhesive), a silicone adhesive (pressure sensitive adhesive), a polyester adhesive and the like are used. If the thickness of the adhesive layer is too thin, a sufficient adhesive force can not be obtained. If the thickness of the adhesive layer is too thick, the resulting laminated product of the cured film and the substrate becomes too hard and the flexibility of the film becomes insufficient.

Examples of the method of applying the photocurable resin composition on a substrate include a roll coating method, a spin coating method, a coil bar method, a dip coating method, and a die coating method. A roll coating method or the like, which can be continuously applied, is preferable in terms of productivity and production cost.

When the obtained composition layer contains a solvent, it is preferable to further include a step (1 ') of removing the solvent. Such solvent removal is carried out by evaporating the solvent from the composition layer by, for example, a heating means using a heating device such as a hot plate or a decompression means using a decompression device, or a combination of these means. The conditions of the heating means and the decompression means can be selected depending on the type of the solvent contained in the composition layer and, for example, in the case of a hot plate, the surface temperature of the hot plate is preferably set in a range of about 50 to 200 캜 . Further, in the decompression means, after the substrate having the composition layer is sealed in a suitable decompressor, the internal pressure of the decompressor may be set to about 1 to 1.0 x 10 ⁵ Pa. By removing the solvent from the composition layer in this way, a composition layer containing no solvent is formed on the substrate.

&Lt; Process (2) >

The exposure is usually performed by irradiation with ultraviolet light. At this time, the ultraviolet rays include light rays in the visible light region, and the photopolymerization initiator develops a photopolymerization initiating ability by light irradiation to cure the composition layer obtained in the step (1). The ultraviolet ray preferably has a wavelength of 200 to 450 nm, and the photopolymerization initiator preferably has an absorption region at a wavelength of 220 to 450 nm. Generally, the wavelength of the ultraviolet ray is shorter than 380 nm, and the wavelength of the visible ray is 380 to 780 nm.

When the wavelength of the ultraviolet ray is less than 200 nm, the ultraviolet ray is likely to be absorbed by the ultraviolet absorbent, the photopolymerization initiating ability of the photopolymerization initiator is not sufficiently manifested and the curability of the composition layer tends to be lowered. The function is degraded. When the wavelength of light is less than 220 nm as the absorption region of the photopolymerization initiator, ultraviolet light is easily absorbed in the ultraviolet absorber and its photopolymerization initiating ability is lowered. When the wavelength exceeds 450 nm, the corresponding photopolymerization initiator is less, There is a possibility that the expression of the function may be insufficient.

The thickness of the cured film thus formed is preferably 2 to 30 占 퐉, more preferably 5 to 25 占 퐉. When the thickness is 2 m or more, the surface hardness tends to be further improved. When the thickness is too large, cracks tend to occur immediately after curing or when exposed under high temperature and high humidity. The thickness of the cured film can be controlled by adjusting the amount per unit area or solid content of the photocurable resin composition applied to the surface of the substrate

[Laminate]

Next, the laminate of this embodiment will be described. In the laminate, a cured film obtained by the above-described method is laminated on at least one surface of the substrate. The laminate of the present embodiment may be also referred to as a laminate comprising a substrate and a cured film containing a cured product of the photo-curing resin composition laminated on at least one surface of the substrate.

It is preferable that such a laminate is a laminate in which a cured film is formed on the surface of a substrate obtained through the steps (1) and (2) of the above-mentioned production method. In addition, the steps (1) and (2) The cured film thus obtained may be peeled off from the substrate, and the other substrate may be pasted with the adhesive layer if necessary. Alternatively, the composition layer obtained in the step (1) of the above production method may be peeled off from the substrate, , And then curing the composition layer by the step (2) of the production method.

The thus obtained laminate according to the present embodiment has a cured film having excellent surface hardness on at least one side of the base material and can be suitably used as a display screen protection plate of a portable information terminal represented by a cellular phone or the like. It can also be used as various members in fields requiring surface hardness, such as a finder part such as a digital camera or a handy video camera, or a display screen protective plate of a portable game machine.

In the present embodiment, in order to manufacture the shielding plate of the display terminal of the portable information terminal with the hardened resin plate, it is necessary to perform processing such as printing and punching, if necessary, and cut to a necessary size. Then, setting it on the display window of the portable information terminal makes it possible to provide a display window with excellent surface hardness.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a cross-sectional view schematically showing the layer structure of a laminate of the present embodiment. FIG. The laminate 5 shown in Fig. 1 has a base material 1 and a cured film 3 formed on one side of the base material 1. Fig. The substrate 1 may be a resin sheet, a resin film, or a multilayer structure. The layered product 5 can be used as a hard coating film, and can be suitably used as a member constituting a display device together with, for example, a polarizing plate.

The laminate of the present embodiment may further have another layer other than the substrate and the cured film. For example, the layered product may be provided with a functional layer on a cured film. Examples of the functional layer include a hard coating layer, an antireflection layer, an antiglare layer (antiglare layer), and an inner fingerprint layer (fingerprint resistant layer). The functional layer may be laminated via an adhesive or a pressure-sensitive adhesive. As the adhesive and the pressure-sensitive adhesive, well-known ones may be appropriately selected.

Since the cured film of the laminated body of the present embodiment is excellent in hardness and bendability, sufficient flexibility and high hardness can be achieved even if a functional layer is additionally provided.

<Display device>

2 is a cross-sectional view schematically showing a first layer constitution example of the display device of the present embodiment. The liquid crystal display device 30 includes a liquid crystal panel 25 and a cured film 3 laminated on one surface of the liquid crystal panel 25. The liquid crystal panel 25 is formed by laminating a polarizing plate 10 on both sides of a liquid crystal cell 20 with an adhesive layer 15 interposed therebetween. In Fig. 2, the polarizing plates 10 disposed on both surfaces of the liquid crystal cell 20 are described as being the same, but they may be different.

The polarizing plate 10 includes a polarizing film 13 and a protective film 11 laminated on both surfaces thereof. The polarizing plate 10 may be provided with the polarizing film 13, and the protective film 11 need not necessarily be laminated on both sides thereof.

The cured film 3 is disposed on the viewing side (viewing side) of the liquid crystal panel 25 and plays a role of protecting the liquid crystal panel 25. In this embodiment, the liquid crystal panel 25 can be regarded as a substrate having a multilayer structure. Further, a part of the liquid crystal panel 25 (for example, the polarizing plate 10) may be regarded as a substrate.

3 is a cross-sectional view schematically showing a second layer configuration example of the display device of the present embodiment. The liquid crystal display device 31 shown in Fig. 3 has a liquid crystal panel 25 and a laminate 5 laminated on one surface of the liquid crystal panel 25. As shown in Fig. The liquid crystal panel 25 and the laminate 5 may be laminated via an adhesive layer 7 including an adhesive or a pressure-sensitive adhesive.

The stacked body 5 is disposed on the viewer side of the liquid crystal panel 25 and serves to protect the liquid crystal panel 25.

2 and 3 show an example of the liquid crystal display device, the display device in the present embodiment is not limited to this. For example, the display device may be a liquid crystal display (LCD), an organic EL display, or the like, and the laminate of this embodiment can be suitably used for such a display device.

(Example)

Hereinafter, the embodiments will be described in more detail with reference to examples and comparative examples, but the present invention is not limited to such examples.

In the following Examples and Comparative Examples, the physical properties were measured as follows.

<Pencil hardness>

And measured according to JIS K 5600-5-4. However, the load was 1 kg.

<Appearance>

The appearance of the laminated product of the obtained cured film and substrate was visually evaluated by the following criteria.

Appearance good that does not contain gold crack: ○

1 to 4 cracks are observed: ×

Example 1

55.2 parts by mass of tetrafunctional acrylate (A-TMMT, manufactured by Shin-Nakamura Chemical Co., Ltd.), 13.8 parts by mass of trifunctional acrylate (A-TMPT manufactured by Shin Nakamura Chemical Co., Ltd.) , 3.4 parts by mass of a silica fine particle (trade name: SA-3400C, manufactured by Soft Materials Co., Ltd.), 27.6 parts by mass of silica particles (PGM-AC-2140Y manufactured by Nissan Chemical Industries, Ltd., particle diameter: 10 to 15 nm) (Trade name: IRGACURE (registered trademark) 184, manufactured by Ciba Specialty Chemicals Co., Ltd.) in an amount of 7% by mass based on the total of the tetrafunctional acrylate and the trifunctional acrylate, 0.1% by mass of a leveling agent (BYK-307, a product of Big Chemical Japan Co., Ltd.), and propylene glycol monomethyl ether in an amount equal to the total amount of each component described above were mixed with stirring to obtain a photocurable resin composition.

A PMMA plate (Sumitomo Chemical Co., Ltd., thickness: 1 mm) was used as a transparent substrate, and the above photo-curable resin composition was coated on the base material with a bar coater so as to have a dry film thickness of 20 占 퐉 to obtain a composition layer . Thereafter, drying was carried out in an oven at 80 DEG C for 3 minutes, and the layer of the composition after drying was irradiated with ultraviolet rays at an energy of 500 mJ / cm &lt; 2 &gt; to be cured to obtain a layered product of the cured film and the substrate. The pencil hardness and appearance of the resulting laminate were measured as described above. The results are shown in Table 1.

Examples 2 to 13 and Comparative Examples 1 to 5

(A-TMPT manufactured by Shin-Nakamura Chemical Co., Ltd.), trifunctional acrylate (A-TMPT manufactured by Shin-Nakamura Chemical Co., Ltd.), polyrotaxane (Manufactured by Nissan Chemical Industries, Ltd., PGM-AC-2140Y: particle size of 10 to 15 nm) were respectively used in amounts shown in Tables 1 to 4 , A layered product of a cured film and a substrate was obtained in the same manner as in Example 1. [ The evaluation results of the pencil hardness and appearance (visual appearance) of the obtained laminate are shown in Tables 1 to 4.

(Industrial availability)

The photo-curable resin composition of the present invention, the method of producing a cured film using the same, and the laminate are used for a display device having an ultraviolet ray absorbing property, for example, provided on a display screen of an electronic image display device such as a plasma display (PD) Can be used for the production of hard coating films.

1: substrate
3:
5:
7: Adhesive layer
10: polarizer
11: Protective film
13: polarizing film
15: Pressure-sensitive adhesive layer
20: liquid crystal cell
25: liquid crystal panel
30, 31: liquid crystal display

Claims (7)

(Meth) acrylate having two or more functional groups, a polyrotaxane, silica particles, and a photopolymerization initiator,
(1) to (4), when the content of the polyfunctional (meth) acrylate is X parts by mass, the content of the polyrotaxane is Y parts by mass and the content of the silica particles is Z parts by mass Wherein the photo-curable resin composition satisfies the following conditions.
(1): X + Y + Z = 100
Equation (2): X? 50
(3): 3? Y? 20
Equation (4): 25? Z? 40 The method according to claim 1,
Wherein the polyrotaxane has a (meth) acryloyl group. A process for producing a photocurable resin composition, comprising the steps of: applying the photocurable resin composition according to any one of claims 1 to 3 on a substrate to obtain a composition layer;
And exposing the composition layer to cure the composition layer. A substrate,
And a cured film laminated on at least one surface of the substrate,
Wherein the cured film comprises a cured product of the photo-curing resin composition according to any one of claims 1 to 3. 5. The method of claim 4,
Wherein the substrate has a multilayer structure. The method according to claim 4 or 5,
Wherein the substrate comprises a (meth) acrylic resin. A display device comprising the laminate according to claim 5 or 6.

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