JPWO2016171187A1 - Photocurable resin composition, method for producing cured film using the same, and laminate comprising the cured film - Google Patents

Abstract

Bifunctional or higher polyfunctional (meth) acrylate, polyrotaxane, silica particles, and photopolymerization initiator are contained, the polyfunctional (meth) acrylate content is X parts by mass, and the polyrotaxane content is Y. The photocurable resin composition which satisfy | fills all the relationship of following formula (1)-(4) when content of the said silica particle is made into Z mass part with a mass part. Formula (1): X + Y + Z = 100 Formula (2): X ≧ 50 Formula (3): 3 ≦ Y ≦ 20 Formula (4): 25 ≦ Z ≦ 40

Description

  The present invention relates to a photocurable resin composition, a method for producing a cured film using the same, and a laminate including the cured film.

  As a photocurable resin composition for forming a hard coat layer on a transparent substrate film, for example, a photocurable resin composition containing a bifunctional or higher polyfunctional (meth) acrylate, a polyrotaxane, and a photopolymerization initiator. (Patent Document 1).

JP 2009-204725 A

  In the photocurable resin composition described in Patent Document 1, the surface hardness (pencil hardness) of the obtained cured film is not always satisfactory.

The present invention includes the following inventions [1] to [5].
[1] A bifunctional or higher polyfunctional (meth) acrylate, polyrotaxane, silica particles, and a photopolymerization initiator are contained, the content of the polyfunctional (meth) acrylate is X parts by mass, and the polyrotaxane is contained. A photocurable resin composition that satisfies all of the following formulas (1) to (4) when the amount is Y parts by mass and the content of the silica particles is Z parts by mass.
Formula (1): X + Y + Z = 100
Formula (2): X ≧ 50
Formula (3): 3 ≦ Y ≦ 20
Formula (4): 25 ≦ Z ≦ 40
[2] The photocurable resin composition according to [1], wherein the polyrotaxane has a (meth) acryloyl group.
[3] A step of applying a photocurable 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 And a method for producing a cured film.
[4] A substrate and a cured film laminated on at least one surface of the substrate, and the cured film includes a cured product of the photocurable resin composition according to [1] or [2]. , Laminate.
[5] The laminate according to [4], wherein the base material has a multilayer structure.
[6] The laminate according to [4] or [5], wherein the base material contains a (meth) acrylic resin.
[7] A display device comprising the laminate according to [5] or [6].

  If the photocurable resin composition of the present invention is used, a cured film having sufficient surface hardness and good appearance can be obtained.

It is sectional drawing which shows the layer structural example of a laminated body typically. It is sectional drawing which shows typically the 1st layer structural example of a display apparatus. It is sectional drawing which shows the 2nd example of a layer structure of a display apparatus typically.

  Hereinafter, preferred embodiments of the present invention will be described in detail. In the present specification, “(meth) acrylate” represents a generic name of acrylate and methacrylate, “(meth) acryloyl group” represents a generic name of acryloyl group and methacryloyl group, and “(meth) acrylic resin” Represents a general term for acrylic resin and methacrylic resin.

[Photocurable resin composition]
The photocurable resin composition of this embodiment contains bifunctional or higher polyfunctional (meth) acrylate, 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) acrylate, ethylene glycol di (Meth) acrylate, triethylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, 3-methylpentanediol di (meth) acrylate, diethylene glycol bis β- (meth) Acryloyloxypropionate, trimethylolethane tri (meth) acrylate, trimethylolpropane 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 [2.2.1] heptane, poly 1, 2-butadiene di (meth) acrylate, 1,2-bis (meth) acryloyloxymethylhexane, nonaethylene glycol di (meth) acrylate, tetradecane ethylene glycol di (meth) acrylate, 10-decanediol (meth) acrylate, 3 , 8-bis (meth) acryloyloxymethyltricyclo [5.2.10] decane, hydrogenated bisphenol A di (meth) acrylate, 2,2-bis (4- (meth) acryloyloxydiethoxyphenyl) propane, 1,4-bis ( (Meth) acryloyloxymethyl) cyclohexane, hydroxypivalate ester neopentyl glycol di (meth) acrylate, bisphenol A diglycidyl ether di (meth) acrylate, epoxy-modified bisphenol A di (meth) acrylate and the like.

<Polyrotaxane>
Polyrotaxane is a pseudopolyrotaxane in which the openings of multiple cyclic molecules are skewered by linear molecules, and the multiple cyclic molecules include the linear molecules (both ends of the linear molecules). Further, a blocking group is arranged so that the cyclic molecule is not released.
(Linear molecule)
The linear molecule contained in the polyrotaxane is not particularly limited as long as it is a molecule or substance that is included in a cyclic molecule and can be integrated non-covalently and is linear. In the present specification, the “linear molecule” means a molecule including a polymer and all other substances satisfying the above requirements. Further, in the present specification, “linear” of “linear molecule” means substantially “linear”. That is, the linear molecule may have a branched chain as long as the cyclic molecule as a rotor is rotatable or the cyclic molecule is slidable or movable on the linear molecule. Further, the length of the “straight chain” is not particularly limited as long as the cyclic molecule can slide or move on the linear molecule.

  Examples of linear molecules include polyvinyl alcohol, polyvinyl pyrrolidone, poly (meth) acrylic acid, cellulose resins (carboxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, etc.), polyacrylamide, polyethylene oxide, polyethylene glycol, polyvinyl acetal type. Hydrophilic polymers such as resin, polyvinyl methyl ether, polyamine, polyethyleneimine, casein, gelatin, starch, or copolymers thereof; polyolefin resins (polyethylene, polypropylene, copolymer resins with other olefin monomers, etc.) , Polyester resin, polyvinyl chloride resin, polystyrene resin (polystyrene, acrylonitrile-styrene copolymer resin, etc.), acrylic resin (polymethylmethacrylate) Acrylate, (meth) acrylic acid ester copolymer, acrylonitrile-methyl acrylate copolymer resin, etc.), polycarbonate resin, polyurethane resin, vinyl chloride-vinyl acetate copolymer resin, polyvinyl butyral resin, etc .; and their derivatives Or a modified body can be mentioned.

  Among the hydrophilic polymers, polyethylene glycol, polypropylene glycol, and a copolymer of polyethylene glycol and polypropylene glycol are preferable. Among the hydrophobic polymers, polyisoprene, polyisobutylene, polybutadiene, polytetrahydrofuran, polydimethylsiloxane, polyethylene and polypropylene are preferable. 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, it is 10,000 or more, for example, 10,000 to 1,000,000, 10,000 to 500,000, or 10,000 to 300,000. In addition, it is preferable that the linear molecule is a biodegradable molecule in terms of “environmentally friendly (ecological)” because the load on the environment is small.

  The linear molecule preferably has reactive groups at both ends. By having this reactive group, it can react easily with a blocking group. The reactive group depends on the 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 it is a cyclic molecule that can include the linear molecule.
In this specification, “cyclic molecule” refers to various cyclic substances including cyclic molecules. In the present specification, “cyclic molecule” refers to a molecule or substance that is substantially cyclic. That is, “substantially ring-shaped” means that the letter “C” is not completely closed, such as the letter “C”, and one end and the other end of the letter “C” are not joined. It is intended to include those having overlapping spiral structures. Furthermore, a ring for a “bicyclo molecule” to be described later can be defined in the same manner as “substantially cyclic” in “cyclic molecule”. That is, one or both rings of the “bicyclo molecule” may not be completely closed like the letter “C”, and one end and the other end of the letter “C” are connected to each other. It may have a spiral structure that is not overlapped.

  Examples of the cyclic molecule include various cyclodextrins (for example, α-cyclodextrin, β-cyclodextrin, γ-cyclodextrin, dimethylcyclodextrin and glucosylcyclodextrin, derivatives or modified products thereof), crown ethers, benzo Examples include crowns, dibenzocrowns, and dicyclohexanocrowns, and derivatives or modified products thereof.

  The above-mentioned cyclodextrins and crown ethers differ in the size of the opening of the cyclic molecule depending on the type. Therefore, the type of linear molecule to be used, specifically, when the linear molecule to be used is assumed to be cylindrical, the cyclic molecule to be used depends on the diameter of the cross section of the cylinder, the hydrophobicity or hydrophilicity of the linear molecule, etc. Can be selected. When a cyclic molecule having a relatively large opening and a cylindrical linear molecule having a relatively small diameter are used, two or more linear molecules can be included in the opening of the cyclic molecule. . Among these, cyclodextrins are preferable from the above-mentioned “environmentally friendly” point because they have biodegradability.

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

  When the cyclic molecule is cyclodextrin, the number of cyclic molecules that include the linear molecule is preferably 0.05 to 0.60, with the maximum inclusion amount being 1, 0.10 to 0.10. 0.50 is more preferable, and 0.20 to 0.40 is still more preferable. If it is less than 0.05, the pulley effect may not be exhibited. If it exceeds 0.60, cyclodextrin, which is a cyclic molecule, may be arranged too densely, and the mobility of cyclodextrin may be reduced. Insolubility in the organic solvent may be strengthened, and the solubility of the resulting polyrotaxane in the organic solvent may be reduced.

  The cyclic molecule preferably has a reactive group outside the ring. When the cyclic molecules are bonded or cross-linked, the reaction can be easily performed using this reactive group. The reactive group depends on the crosslinking agent used, and examples thereof include a hydroxyl group, an amino group, a carboxyl group, a thiol group, and an aldehyde group. Moreover, it is good to use the group which does not react with a block group in the case of reaction (blocking reaction) with a linear molecule.

(Block base)
As the blocking group, any group may be used as long as the cyclic molecule maintains a form in which the cyclic molecule is skewered with a linear molecule. Examples of such a group include a group having “bulkiness” and / or a group having “ionicity”. Here, the “group” means various groups including a molecular group and a polymer group. In addition, the “ionicity” of the group having “ionicity” and the “ionicity” of the cyclic molecule influence each other, for example, by repulsion, the cyclic molecule is skewered by linear molecules. It is possible to retain the form.

  The blocking group may be a polymer main chain or a side chain as long as it retains a skewered shape as described above. When the blocking group is the polymer A, the compound according to the present embodiment is used as a matrix on the contrary, even if the polymer A is used as a matrix and the compound according to the present embodiment (polyrotaxane) is included in a part of the block group. There may be a form in which the polymer A is included in a part thereof. Thus, by combining with the polymer A having various properties, a composite material having a combination of the properties of the compound according to the present embodiment and the properties of the polymer A can be formed.

  Specifically, as a blocking group of the molecular group, dinitrophenyl groups such as 2,4-dinitrophenyl group and 3,5-dinitrophenyl group, cyclodextrins, adamantane groups, trityl groups, fluoresceins and pyrene And derivatives or modified products thereof. More specifically, for example, as a blocking group in the case of using α-cyclodextrin as a cyclic molecule and polyethylene glycol as a linear molecule, cyclodextrins, 2,4-dinitrophenyl group, 3,5-dinitrophenyl And dinitrophenyl groups such as a group, adamantane groups, trityl groups, fluoresceins and pyrenes, and derivatives or modified products thereof.

  Next, the modified polyrotaxane that can be preferably used in the photocurable resin composition of the present embodiment will be described. In this embodiment, a polyrotaxane in which a plurality of modifications described below are used in combination can be preferably used.

<Cross-linked polyrotaxane>
A 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. At this time, the chemical bond may be a simple bond or a bond via various atoms or molecules.
In addition, a molecule in which a cyclic molecule has a bridged ring structure, that is, a “bicyclo molecule” having first and second rings can be used. In this case, for example, a “bicyclo molecule” and a linear molecule can be mixed, and the crosslinked polyrotaxane can be obtained by including the linear molecule in a skewered manner in the first and second rings of the “bicyclo molecule”.
This crosslinked polyrotaxane has viscoelasticity because the cyclic molecules penetrating the linear molecule in a skewered manner can move along the linear shape (pulley effect). The tension can be uniformly dispersed by the effect, and the internal stress can be relaxed.

<Hydrophobic modified polyrotaxane>
When the cyclic molecule of polyrotaxane is a cyclodextrin such as α-cyclodextrin, in this embodiment, at least one hydroxyl group of cyclodextrin is substituted with another organic group (hydrophobic group). Since solubility in the solvent contained in the forming composition is improved, it is more preferably used.

  Specific examples of hydrophobic groups include, for example, alkyl groups, benzyl groups, benzene derivative-containing groups, acyl groups, silyl groups, trityl groups, nitrate ester groups, tosyl groups, alkyl-substituted ethylenically unsaturated groups as photocuring sites, and thermosetting sites. Examples thereof include, but are not limited to, an alkyl-substituted epoxy group. Moreover, in said hydrophobic modification polyrotaxane, you may have 1 type of the above-mentioned hydrophobic group individually or in combination of 2 or more types.

The degree of modification with the hydrophobic group is preferably 0.02 or more, more preferably 0.04 or more, and more preferably 0.06 or more, assuming that the maximum number of cyclodextrin hydroxyl groups that can be modified is 1. More preferably.
If it is less than 0.02, the solubility in an organic solvent will not be sufficient, and insoluble bumps (protrusions derived from adhesion of foreign matter, etc.) may be generated.
Here, the maximum number that the hydroxyl groups of cyclodextrin can be modified is, in other words, the total number of hydroxyl groups that cyclodextrin had before modification. In other words, the degree of modification is the ratio of the number of modified hydroxyl groups to the total number of hydroxyl groups.
Although at least one hydrophobic group may be used, in that case, it is preferable to have one hydrophobic group for each cyclodextrin ring. Further, by introducing a hydrophobic group having a functional group, the reactivity with other polymers can be improved.

<Polyrotaxane having an unsaturated double bond>
An unsaturated bond group can be introduced into the portion corresponding to the cyclic molecule. By introducing this group, polymerization with a polymerizable compound becomes possible.
Introduction of an unsaturated bond group can be carried out, for example, by substituting at least a part of a cyclic molecule having a hydroxyl group (—OH) such as cyclodextrin with an unsaturated bond group, preferably an unsaturated double bond group. .
Examples of unsaturated bond groups such as unsaturated double bond groups include olefinyl groups (groups having olefinic double bonds), such as acrylic groups, (meth) acryloyl groups, vinyl ether groups, and styryl groups. Although it can mention, it is not limited to this.

  The unsaturated double bond group can be introduced by the following method. That is, a method by carbamate bond formation with an isocyanate compound or the like; a method by ester bond formation by a carboxylic acid compound, an acid chloride compound or an acid anhydride; a method by silyl ether bond formation by a silane compound or the like; a carbonate bond formation by a chlorocarbonic acid compound And 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 it introduce | transduces via an ether bond or an ester bond, the (meth) acryloyl reagent which has active groups, such as a glycidyl group and an acid chloride, can also be used.

  The step of substituting the hydroxyl group of the cyclic molecule with an unsaturated double bond group may be before the step of preparing the pseudopolyrotaxane, between the steps, or after the step. Further, it may be before the step of preparing the polyrotaxane by blocking the pseudopolyrotaxane, between the steps, or after the step. Furthermore, when the polyrotaxane is a crosslinked polyrotaxane, it may be before the step of crosslinking the polyrotaxanes, between the steps, or after the step. It can also be provided at these two or more times. The substitution step is preferably performed after the polyrotaxane is prepared by blocking the pseudopolyrotaxane and before the crosslinking of the polyrotaxane. The conditions used in the substitution step depend on the unsaturated double bond group to be substituted, 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 hydrophobized modified polyrotaxane, more preferably a polyrotaxane having an unsaturated double bond, and further preferably a polyrotaxane having a (meth) acryloyl group.

  Examples of the polyrotaxane having such a (meth) acryloyl group include Celum (registered trademark) Key Mixture SM3400C, SA3400C, SA2400C manufactured by Advanced Soft Materials Co., Ltd.

<Silica particles>
As silica particles, powder silica, organosilica sol in which silica particles are dispersed in a solvent, or the like can be used. These silica particles are generally commercially available.
As the powder silica, Aerosil (registered trademark) 130, Aerosil (registered trademark) 300, Aerosil (registered trademark) 380, Aerosil (registered trademark) TT600, Aerosil (registered trademark) OX50, etc. (above, manufactured by Nippon Aerosil Co., Ltd.) ), SYLYSIA 470 (manufactured by Fuji Silysia Co., Ltd.), SG flake (manufactured by Nippon Sheet Glass Co., Ltd.), and the like.
As the organosilica sol, isopropyl alcohol-dispersed silica sol (IPA-ST, IPA-ST-L, IPA-ST-UP, IPA-ST-ZL), methanol-dispersed silica sol (MA-ST-M, MA-ST-L, MA) -ST-ZL, MA-ST-UP), dimethylacetamide-dispersed silica sol (DMAC-ST, DMAC-ST-ZL), ethylene glycol-dispersed silica sol (EG-ST, EG-ST-ZL), ethylene glycol mono-n-propyl Ether dispersed silica sol (NPC-ST-30), propylene glycol monomethyl ether dispersed silica sol (PGM-ST), ethyl acetate dispersed silica sol (EAC-ST), propylene glycol monomethyl ether acetate dispersed silica sol (PMA-ST), methyl ethyl keto Dispersed silica sol (MEK-ST, MEK-ST-40, MEK-ST-L, MEK-ST-ZL, MEK-ST-UP, MEK-AC-2104Z, MEK-AC-2130Y, MEK-AC-4130Y, MEK -AC-5140Z), methyl isobutyl ketone-dispersed silica sol (MIBK-ST, MIBK-ST-L, MIBK-SD, MIBK-SD-L) (manufactured by Nissan Chemical Industries, Ltd.), OSCAL (registered trademark) series (JGC Catalysts & Chemicals Co., Ltd.).

As for the particle diameter of the silica particles, the average primary particle diameter is preferably 100 nm or less, more preferably 30 nm or less. When the average primary particle diameter exceeds 100 nm, the transparency of the resulting coating film tends to be impaired.
In addition, in this specification, the average primary particle diameter of a silica particle shows the value measured by JISZ8828 dynamic light scattering method.

In the photocurable resin composition of the present embodiment, the content of bifunctional or higher polyfunctional (meth) acrylate 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. Sometimes all of the relationships of the following formulas (1) to (4) are satisfied.
Formula (1): X + Y + Z = 100
Formula (2): X ≧ 50
Formula (3): 3 ≦ Y ≦ 20
Formula (4): 25 ≦ Z ≦ 40

In formula (1) and formula (2), the bifunctional or higher polyfunctional (meth) acrylate content is 50 with respect to a total of 100 parts by mass of the bifunctional or higher polyfunctional (meth) acrylate, polyrotaxane and silica particles. It represents that it is at least part by mass. As X becomes smaller than 50, the surface hardness of the obtained cured film tends to decrease. X is preferably 70 or less. The formula (2) is more preferably the formula (2 ′). More preferably, X is greater than 50.
Formula (2 ′): 50 ≦ X ≦ 70

In formula (1) and formula (3), the content of the polyrotaxane is 3 parts by mass or more and 20 parts by mass or less with respect to a total of 100 parts by mass of the bifunctional or higher polyfunctional (meth) acrylate, polyrotaxane and silica particles. Represents something. As Y becomes smaller than 3, cracks tend to occur in the resulting cured film and the appearance tends to be impaired. As Y is 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

In formula (1) and formula (4), the silica particles are 25 parts by mass or more and 40 parts by mass or less with respect to a total of 100 parts by mass of the bifunctional or higher polyfunctional (meth) acrylate, polyrotaxane and silica particles. Represents. As Z becomes smaller than 25, the surface hardness of the resulting cured film tends to decrease. As Z is larger than 40, cracks are likely to occur in the resulting cured film and the appearance tends to be impaired. The formula (4) is preferably the formula (4 ′).
Formula (4 ′): 25 <Z <40

<Photopolymerization initiator>
As the photopolymerization initiator, a polymerization initiator that can exhibit photopolymerization initiating ability by light irradiation in the presence of an ultraviolet absorber is preferable. For example, acetophenone, acetophenone benzyl ketal, anthraquinone, 1- (4-isopropylphenyl-2-hydroxy) 2-methylpropan-1-one, carbazole, xanthone, 4-chlorobenzophenone, 4,4′-diaminobenzophenone, 1,1-dimethoxydeoxybenzoin, 3,3′-dimethyl-4-methoxybenzophenone, thioxanthone, 2 , 2-dimethoxy-2-phenylacetophenone, 1- (4-dodecylphenyl) -2-hydroxy-2-methylpropan-1-one, 2-methyl-1- [4- (methylthio) phenyl] -2-morpho Linopropan-1-one, triphenylamino 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, fluorenone, fluorene, benzaldehyde, benzoin ethyl ether, benzoisopropyl ether , Benzophenone, Michler ketone, 3-methylacetophenone, 3,3 ′, 4,4′-tetra-tert-butylperoxycarbonylbenzophenone (BTTB), 2- (dimethylamino) -1- [4- (morpholinyl) phenyl] -2- (phenylmethyl) -1-butanone, 4-benzoyl-4′-methyldiphenyl sulfide, 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 with respect to a total of 100 parts by mass of the bifunctional or higher polyfunctional (meth) acrylate, polyrotaxane and silica particles. It is. When the content of the photopolymerization initiator is more than the above range, the photopolymerization initiator that has not been used for initiating the photopolymerization may remain, which may cause a problem such as a decrease in visible light transmittance. On the other hand, when the amount is less than the above range, the photopolymerization initiating ability is not sufficiently exhibited, and the curing of the ultraviolet curable resin may be insufficient.

<Other ingredients>
The photocurable resin composition of the present embodiment may further contain an antistatic agent. As such an antistatic agent, metal oxides and metal salts are preferred. 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. Although the content of this antistatic agent depends on the antistatic performance to be obtained, it is preferably 1 to 100 parts by mass in total of bifunctional or higher polyfunctional (meth) acrylate, polyrotaxane, silica particles and photopolymerization initiator. 100 parts by mass. When the content of the antistatic agent is larger than the above range, there is a tendency that the ultraviolet curable property of the photocurable resin composition is hindered or the visible light transmittance of the obtained cured film is lowered. The particle size of the antistatic agent is preferably 0.001 to 0.1 μm. When the particle size is too small, industrial production is difficult, and when the particle size is too large, the transparency of the resulting cured film tends to decrease.

  Furthermore, in the photocurable resin composition of the present embodiment, additives such as an ultraviolet absorber, an antioxidant, a colorant, a fluorine additive that imparts water and oil repellency, and a leveling agent are added as necessary. It may be included. By containing the leveling agent, the smoothness and scratch resistance of the cured film can be improved.

  It is preferable that the photocurable resin composition of the present embodiment further contains a solvent in that it is subjected to a coating step described later. Examples of the solvent include methanol, ethanol, 1-propanol, 2-propanol (isopropyl alcohol), 1-butanol, 2-butanol (sec-butyl alcohol), 2-methyl-1-propanol (isobutyl alcohol), 2 Alcohol solvents such as methyl-2-propanol (tert-butyl alcohol); 2-ethoxyethanol, 2-butoxyethanol, 3-methoxy-1-propanol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol Alkoxy alcohol 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; ester solvents such as ethyl acetate and butyl acetate; And the like.

  The content of the solvent is preferably 20 to 10,000 parts by mass with respect to 100 parts by mass in total of the polyfunctional (meth) acrylate having two or more functions, polyrotaxane, silica particles, and photopolymerization initiator.

<Manufacture of a photocurable resin composition>
The photocurable resin composition of the present embodiment includes a bifunctional or higher polyfunctional (meth) acrylate, a polyrotaxane, silica particles, a photopolymerization initiator, and optionally a solvent, an antistatic agent, and other additives. And the order of mixing is not particularly limited.

[Method for producing cured film]
Next, the manufacturing method of the cured film using the photocurable resin composition of this embodiment is demonstrated. The method for producing the cured film includes the following steps (1) and (2).
(1) A step of obtaining the composition layer by applying the above-mentioned photocurable resin composition on a substrate (2) A step of exposing the composition layer to cure the composition layer

<Step (1)>
As the resin constituting the substrate, (meth) acrylic resin, polyester resin, polycarbonate resin, polycyclic olefin resin, polystyrene resin, methacryl-styrene copolymer (MS resin), acrylonitrile-styrene copolymer (AS resin) ), Polyvinylidene fluoride resin (PVDF resin), and the like. Among these, a (meth) acrylic resin is preferable because it has a high transparency, a high surface hardness, and a cured film having high scratch resistance. A methacrylic resin is more preferable.

  The thickness of the substrate is preferably 30 to 300 μm, more preferably 50 to 200 μm. When this thickness is thinner than the above range, the strength of the resulting laminate of the cured film and the substrate may not be maintained. On the other hand, when it is thicker than the above range, the transparency of the substrate is lowered or the flexibility is lowered, which is not preferable. Various additives may be contained in the base material. Examples of such additives include stabilizers, plasticizers, lubricants, flame retardants, and the like.

  The substrate may have a flat surface like a normal plate (sheet) or film, or may have a curved surface like a convex lens or a concave lens. Further, a fine structure such as fine irregularities may be provided on the surface.

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

The substrate may be a single layer or a multilayer structure. As the resin base material having a multilayer structure, one in which a (meth) acrylic resin layer is laminated on at least one surface of the main resin layer is preferable. Moreover, as a base material of a multilayer structure, the optical laminated body containing a polarizing plate, a phase difference plate, etc. is preferable.
The substrate may be in the form of a plate (sheet), a film, a multilayer structure or the like, and the substrate surface may be flat or curved.

  The base material 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 according to the material of the substrate or the cured film. For example, an acrylic adhesive (adhesive), a silicone adhesive (adhesive), a polyester adhesive, etc. Is used. If the thickness of the adhesive layer is too thin, sufficient adhesive force cannot be obtained, and if it is too thick, the resulting laminate of the cured film and the substrate becomes too hard and lacks flexibility as a film. A range of 1-1 μm is preferred.

  Examples of the method for applying the above-mentioned 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 method that can be applied continuously, such as a roll coating method, is preferred in terms of productivity and production cost.

When the obtained composition layer contains a solvent, it is preferable to further include a step (1 ′) for removing the solvent. Such solvent removal is performed, for example, by evaporating the solvent from the composition layer by a heating means using a heating device such as a hot plate or a decompression means using a decompression device, or by combining these means. Is called. The conditions for the heating means and the decompression means can be selected according to the type of the solvent contained in the composition layer. For example, in the case of a hot plate, the surface temperature of the hot plate is preferably in the range of about 50 to 200 ° C. . In the decompression means, after the base material having the composition layer is sealed in an appropriate decompressor, the internal pressure of the decompressor may be set to about 1 to 1.0 × 10 ⁵ Pa. Thus, by removing the solvent from the composition layer, a composition layer containing no solvent is formed on the substrate.

<Step (2)>
The exposure is usually performed by irradiation with ultraviolet rays. At this time, ultraviolet rays include light in the visible light region, and the photopolymerization initiator develops photopolymerization initiating ability by light irradiation and cures the composition layer obtained in the step (1). The ultraviolet light preferably has a wavelength of 200 to 450 nm, and the photopolymerization initiator preferably has an absorption region at a light wavelength of 220 to 450 nm. In general, the wavelength of ultraviolet light is shorter than 380 nm, and the wavelength of visible light is 380 to 780 nm.

  When the wavelength of the ultraviolet light is less than 200 nm, the ultraviolet light is easily absorbed by the ultraviolet absorber, and the photopolymerization initiating ability of the photopolymerization initiator is not sufficiently expressed, and the curability of the composition layer tends to be lowered, When it exceeds 450 nm, the function as ultraviolet rays is reduced. When the wavelength of light is less than 220 nm as the absorption region of the photopolymerization initiator, the ultraviolet absorber is easily absorbed by ultraviolet rays, and the photopolymerization initiation ability is reduced. When the wavelength exceeds 450 nm, the corresponding photopolymerization initiator is used. And there is a possibility that the photopolymerization initiating ability due to ultraviolet rays is insufficient.

  The thickness of the cured film thus formed is preferably 2 to 30 μm, more preferably 5 to 25 μm. If the thickness is 2 μm or more, the surface hardness tends to be further improved. If the thickness is too large, cracks are likely to occur immediately after curing or when exposed to high temperature and high humidity. The thickness of the cured film can be adjusted by adjusting the amount per area and solid content concentration of the photocurable resin composition applied to the surface of the substrate.

[Laminate]
Next, the laminated body of this embodiment is demonstrated. In the laminate, a cured film obtained by the production method is laminated on at least one surface of the substrate. The laminated body of this embodiment can also be called a laminated body provided with a base material and the cured film containing the hardened | cured material of the photocurable resin composition laminated | stacked on the at least one surface of the base material.

  Such a laminate is preferably a laminate in a state where a cured film is formed on the surface of the base material obtained through the steps (1) and (2) of the above production method. It may be a laminate obtained by peeling the cured film obtained through the steps (1) and (2) from the base material and sticking to another base material through the adhesive layer as necessary, The composition layer obtained in the step (1) of the production method is peeled off from the substrate, and is attached to another substrate via the adhesive layer as necessary, and then the step (2) of the production method is used. It may be a laminate obtained by curing the composition layer.

  The laminate of the present embodiment thus obtained has a cured film having excellent surface hardness formed on at least one surface of the substrate, and is suitable as a display window protection plate for portable information terminals typified by mobile phones. Can be used. It can also be used as various members in fields requiring surface hardness, such as viewfinders for digital cameras and handy video cameras, and display window protection plates for portable game machines.

  In this embodiment, in order to produce a display window protection plate for a portable information terminal from a high-hardness resin plate, first, if necessary, processing such as printing, drilling, and the like may be performed. . After that, if it is set on the display window of the portable information terminal, it can be made a display window with excellent surface hardness.

  FIG. 1 is a cross-sectional view schematically showing the layer configuration of the laminate of this embodiment. A laminate 5 shown in FIG. 1 has a base material 1 and a cured film 3 formed on one surface of the base material 1. The substrate 1 may be a resin sheet, a resin film, or a multilayer structure. The laminate 5 can be used as a hard coat film, and can be suitably used as a member constituting a display device together with a polarizing plate, for example.

  The laminated body of this embodiment may further have other layers other than a base material and a cured film. For example, the laminated body may be provided with a functional layer on the cured film. Examples of the functional layer include a hard coat layer, an antireflection layer, an antiglare layer, and an anti-fingerprint layer. The functional layer may be laminated via an adhesive or a pressure-sensitive adhesive. What is necessary is just to select a well-known thing suitably as an adhesive agent and an adhesive.

  In the laminate of the present embodiment, since the cured film is excellent in hardness and flexibility, even if a functional layer is further provided, sufficient flexibility and high hardness can be achieved.

<Display device>
FIG. 2 is a cross-sectional view schematically showing a first layer configuration 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 obtained by laminating the polarizing plate 10 on both surfaces of the liquid crystal cell 20 with the adhesive layer 15 interposed therebetween. In FIG. 2, the polarizing plates 10 arranged 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. In addition, the polarizing plate 10 should just be provided with the polarizing film 13, and the protective film 11 does not necessarily need to be laminated | stacked on the both surfaces.

  The cured film 3 is disposed on the 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 base material having a multilayer structure. Further, a part of the liquid crystal panel 25 (for example, the polarizing plate 10) can be regarded as a base material.

  FIG. 3 is a cross-sectional view schematically showing a second layer configuration example of the display device of the present embodiment. A liquid crystal display device 31 shown in FIG. 3 includes a liquid crystal panel 25 and a stacked body 5 stacked on one surface of the liquid crystal panel 25. The liquid crystal panel 25 and the laminated body 5 can be laminated | stacked through the contact bonding layer 7 containing an adhesive agent or an adhesive.

  The stacked body 5 is disposed on the viewing side of the liquid crystal panel 25 and plays a role of protecting the liquid crystal panel 25.

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

  Hereinafter, although the said embodiment is described further more concretely by giving an Example and a comparative example, this invention is not limited to the range of these Examples.

In each of the following Examples and Comparative Examples, each physical property was measured as follows.
<Pencil hardness>
It measured based on JISK5600-5-4. However, the load was 1 kg.
<Appearance>
The appearance of the obtained laminate of the cured film and the substrate was visually observed and evaluated according to the following criteria.
Good appearance with no cracks: ○
One to four cracks: x

Example 1
4-functional acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., A-TMMT) 55.2 parts by mass, trifunctional acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., A-TMPT) 13.8 parts by mass, reactive polyrotaxane (Advanced 3.4 parts by mass of Soft Materials Co., Ltd., SA-3400C), 27.6 parts by mass of silica particles (manufactured by Nissan Chemical Co., Ltd., PGM-AC-2140Y: particle size 10 to 15 nm), the above tetrafunctional acrylate And 7% by mass of a photopolymerization initiator (manufactured by Ciba Specialty Chemicals Co., Ltd., IRGACURE (registered trademark) 184) based on the total of the trifunctional acrylate and 0.1% of the total of the tetrafunctional acrylate and the trifunctional acrylate. A mass% leveling agent (BYK-307, manufactured by Big Chemie Japan Co., Ltd.) and the same amount of propire as the total amount of the above components. It was mixed by stirring glycol monomethyl ether, to obtain a photocurable resin composition.

A PMMA plate (Sumitomo Chemical Co., Ltd., thickness: 1 mm) was used as the transparent substrate, and the photocurable resin composition was applied onto the substrate with a bar coater so as to have a dry film thickness of 20 μm. A composition layer was obtained. Then, it dried for 3 minutes in 80 degreeC oven, and irradiated the ultraviolet-ray with the energy of 500 mJ / cm < ² > to the composition layer after drying, and obtained the laminated body of the cured film and the base material. 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
In Example 1, tetrafunctional acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., A-TMMT), trifunctional acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., A-TMPT), polyrotaxane (manufactured by Advanced Soft Materials Co., Ltd.) SA-3400C) and silica particles (manufactured by Nissan Chemical Co., Ltd., PGM-AC-2140Y: particle diameter of 10 to 15 nm) are the same as in Example 1 except that the amounts are respectively shown in Tables 1 to 4. Thus, a laminate of the cured film and the substrate was obtained. The result of having evaluated the pencil hardness and external appearance (visual observation) of the obtained laminated body is shown to Tables 1-4.

  A photocurable resin composition of the present invention, a method for producing a cured film using the same, and a laminate are, for example, ultraviolet absorption provided on a display screen of an electronic image display device such as a plasma display (PD) or a liquid crystal display (LCD). It can use for manufacture of the hard coat film which has property.

DESCRIPTION OF SYMBOLS 1 ... Base material, 3 ... Cured film, 5 ... Laminated body, 7 ... Adhesive layer, 10 ... Polarizing plate, 11 ... Protective film, 13 ... Polarizing film, 15 ... Adhesive layer, 20 ... Liquid crystal cell, 25 ... Liquid crystal panel , 30, 31 ... Liquid crystal display device.

Claims (7)

Containing a bifunctional or higher polyfunctional (meth) acrylate, a polyrotaxane, silica particles, and a photopolymerization initiator;
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, the following formulas (1) to (4) A photocurable resin composition satisfying all of the above.
Formula (1): X + Y + Z = 100
Formula (2): X ≧ 50
Formula (3): 3 ≦ Y ≦ 20
Formula (4): 25 ≦ Z ≦ 40   The photocurable resin composition according to claim 1, wherein the polyrotaxane has a (meth) acryloyl group. Applying the photocurable resin composition according to claim 1 or 2 onto a substrate to obtain a composition layer;
Exposing the composition layer to cure the composition layer;
The manufacturing method of the cured film containing this. A substrate;
A cured film laminated on at least one surface of the substrate;
With
The laminated body in which the said cured film contains the hardened | cured material of the photocurable resin composition of Claim 1 or 2.   The laminate according to claim 4, wherein the substrate has a multilayer structure.   The laminate according to claim 4 or 5, wherein the substrate contains a (meth) acrylic resin.   A display device comprising the laminate according to claim 5.

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