JP2019164294A - Image display device, light curable resin composition, and film material - Google Patents

Abstract

To provide an image display device that includes a shock absorption layer excellent in shock resistance, and a light curable resin composition and a film material that can form such a shock absorption layer.SOLUTION: An image display device 10 comprises: an image display member 13; and a shock absorption layer 11 that is arranged on one side or both sides of the image display member 13. The shock absorption layer 11 is a cured product of a light curable resin composition containing a copolymer containing a monomer unit derived from a first (meth)acryloyl compound and a monomer unit derived from a siloxane compound having an ethylenically unsaturated group, a second (meth)acryloyl compound, and a photopolymerization initiator.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an image display device, a photocurable resin composition, and a film material.

  Image display devices such as organic electroluminescence (organic EL) and liquid crystal are used for protecting an image display member, a function improving member that improves the characteristics of light emitted from the image display member, and protecting the image display member from oxygen, moisture, and the like. It is constituted by laminating a plurality of members such as a barrier member and a fixing member for fixing these members (for example, see Patent Document 1).

JP 2017-120758 A

  In recent years, reduction in weight, thickness, or flexibility of image display devices has been studied. However, with such a study, the strength of each member tends to decrease. For example, when an impact such as external stress or pressure during assembly of the image display device is applied to the image display device, the image display member, the barrier member, or the like may be damaged. Therefore, it has been studied to introduce an impact absorbing layer that can also act as a fixing member in the image display device.

  The present invention has been made in view of such a situation, and an image display device provided with an impact absorbing layer excellent in impact resistance, and a photocurable resin composition capable of forming such an impact absorbing layer. It aims at providing a thing and a film material.

  One aspect of the present invention includes an image display member and a shock absorbing layer disposed on one side or both sides of the image display member, and the shock absorbing layer is a monomer derived from the first (meth) acryloyl compound. A photocurable resin composition comprising a copolymer containing a monomer unit derived from a siloxane compound having a unit and an ethylenically unsaturated group, a second (meth) acryloyl compound, and a photopolymerization initiator An image display device that is a cured product of the above is provided.

  The 1st (meth) acryloyl compound may contain the alkyl (meth) acrylate which has a C1-C18 alkyl group, and the (meth) acrylate which has a hydroxyl group. The copolymer is 50 to 90 parts by mass of a monomer unit derived from an alkyl (meth) acrylate having an alkyl group having 1 to 18 carbon atoms, and 5 to 30 monomer units derived from a (meth) acrylate having a hydroxyl group. 5-30 mass parts of monomer units derived from the mass part and the siloxane compound which has an ethylenically unsaturated group may be included.

  In another aspect, the present invention provides a copolymer comprising a monomer unit derived from a first (meth) acryloyl compound and a monomer unit derived from a siloxane compound having an ethylenically unsaturated group; And a photopolymerization initiator, and a photocurable resin composition used for forming a shock absorbing layer of an image display device.

  The 1st (meth) acryloyl compound may contain the alkyl (meth) acrylate which has a C1-C18 alkyl group, and the (meth) acrylate which has a hydroxyl group. The copolymer is 50 to 90 parts by mass of a monomer unit derived from an alkyl (meth) acrylate having an alkyl group having 1 to 18 carbon atoms, and 5 to 30 monomer units derived from a (meth) acrylate having a hydroxyl group. 5-30 mass parts of monomer units derived from the mass part and the siloxane compound which has an ethylenically unsaturated group may be included.

  In another aspect, the present invention includes a resin layer and a pair of base material layers laminated so as to sandwich the resin layer, and the resin layer is used to form an impact absorption layer of the image display device. A film material, wherein the resin layer comprises a monomer unit derived from the first (meth) acryloyl compound and a monomer unit derived from a siloxane compound having an ethylenically unsaturated group; The film material which is a hardened | cured material of the photocurable resin composition containing 2 (meth) acryloyl compounds of 2 and a photoinitiator is provided.

  The 1st (meth) acryloyl compound may contain the alkyl (meth) acrylate which has a C1-C18 alkyl group, and the (meth) acrylate which has a hydroxyl group. The copolymer is 50 to 90 parts by mass of a monomer unit derived from an alkyl (meth) acrylate having an alkyl group having 1 to 18 carbon atoms, and 5 to 30 monomer units derived from a (meth) acrylate having a hydroxyl group. 5-30 mass parts of monomer units derived from the mass part and the siloxane compound which has an ethylenically unsaturated group may be included. The haze of the resin layer may be 5% or less.

  ADVANTAGE OF THE INVENTION According to this invention, an image display apparatus provided with the impact-absorbing layer excellent in impact resistance, and the photocurable resin composition and film material which can form such an impact-absorbing layer are provided.

It is sectional drawing which shows typically one Embodiment of an image display apparatus. It is sectional drawing which shows typically one Embodiment of a film material. It is the schematic which shows an example of the measuring apparatus of an acceleration decay rate typically.

  Embodiments of the present invention will be described below with reference to the drawings as appropriate. However, the present invention is not limited to the following embodiments.

  In the present specification, the (meth) acryloyl compound means an acryloyl compound or a methacryloyl compound corresponding thereto. The same applies to other similar expressions such as (meth) acrylate and (meth) acryloyl groups.

<Image display device>
An image display device according to an embodiment includes an image display member and a shock absorbing layer disposed on one side or both sides of the image display member. FIG. 1 is a cross-sectional view schematically showing an embodiment of an image display device. The image display device 10 illustrated in FIG. 1 includes a substrate 12, a shock absorbing layer 11, an image display member 13, a function improving member 14, and a barrier member 15 in this order. The shock absorbing layer 11 may be disposed between the image display member 13 and the function improving member 14. Further, the shock absorbing layer 11 is further disposed on the opposite side of the substrate 12 from the image display member 13, between the function improving member 14 and the barrier member 15, or on the opposite side of the barrier member 15 from the function improving member 14. May be.

  The image display device 10 is not particularly limited, but may be a liquid crystal device, an organic electroluminescence (organic EL) device, or the like. The image display device 10 is preferably an organic EL device.

  The substrate 12 may be a glass substrate, a metal substrate, a resin substrate, or the like. The substrate 12 may be a flexible substrate or a thin glass substrate.

  In one embodiment, the image display member 13 may be an organic EL light emitting element including a pixel electrode, an intermediate layer including an organic light emitting layer, and a counter electrode in this order. The pixel electrode may be a reflective electrode. The counter electrode may be a transparent electrode. The intermediate layer includes an organic light emitting layer. In addition to the organic light emitting layer, the intermediate layer includes a hole injection layer (HIL), a hole transport layer (HTL), an electron transport layer (ETL), an electron injection layer (EIL), and the like. Also good.

  The function improving member 14 is a layer having a function of improving the characteristics of the light emitted from the image display member 13, and those generally used in the organic EL field can be used.

  The barrier member 15 is a sealing layer for protecting from oxygen, moisture, and the like, and those generally used in the organic EL field can be used.

  The shock absorbing layer 11 is a cured product of a photopolymerizable resin composition described later. When the shock absorbing layer 11 is a cured product of the photopolymerizable resin composition, flexibility and toughness can be imparted, and high impact resistance can be obtained. The shock absorbing layer 11 can be formed from a photocurable resin composition or a film material described later.

<Photocurable resin composition>
The photocurable resin composition according to one embodiment includes a specific copolymer (hereinafter sometimes referred to as “component (A)”) and a second (meth) acryloyl compound (hereinafter referred to as “(B)”. And a photopolymerization initiator (hereinafter also referred to as “component (C)”), and is used to form a shock absorbing layer of an image display device.

(A) Component: Copolymer The (A) component includes a monomer unit derived from the first (meth) acryloyl compound and a monomer unit derived from a siloxane compound having an ethylenically unsaturated group.

  The first (meth) acryloyl compound is a compound having one (meth) acryloyl group. Examples of the first (meth) acryloyl compound include (meth) acrylic acid, (meth) acrylamide, alkyl (meth) acrylate, (meth) acrylate having a hydroxyl group, (meth) acrylate having an alkylene glycol chain, and an aromatic ring. (Meth) acrylate having alicyclic group, (meth) acrylate having alicyclic group, (meth) acrylamide derivative, (meth) acryloylmorpholine, tetrahydrofurfuryl (meth) acrylate, and (meth) acrylate having isocyanate group. You may use these individually by 1 type or in combination of 2 or more types. Among these, the first (meth) acryloyl compound preferably includes an alkyl (meth) acrylate and a (meth) acrylate having a hydroxyl group.

  An alkyl (meth) acrylate is a compound having an alkyl group and one (meth) acryloyl group. Examples of the alkyl (meth) acrylate include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, tert-butyl (meth) acrylate, and n-pentyl (meth). Acrylate, n-hexyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isodecyl (meth) acrylate, dodecyl (meth) acrylate, stearyl (meth) acrylate, Examples include isostearyl (meth) acrylate. The alkyl (meth) acrylate preferably includes an alkyl (meth) acrylate having a linear or branched alkyl group having 1 to 18 carbon atoms, and includes n-butyl (meth) acrylate, isooctyl (meth) acrylate, More preferably, it includes stearyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, or n-octyl (meth) acrylate, and more preferably includes n-butyl (meth) acrylate or 2-ethylhexyl (meth) acrylate. . The alkyl (meth) acrylate is preferably an alkyl acrylate rather than an alkyl methacrylate.

  A (meth) acrylate having a hydroxyl group is a compound having a hydroxyl group and one (meth) acryloyl group. Examples of the (meth) acrylate having a hydroxyl group include 2-hydroxyethyl (meth) acrylate, 1-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 1- Hydroxyalkyl (meth) acrylates such as hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 3-hydroxybutyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 1-hydroxybutyl (meth) acrylate, etc. Etc. The (meth) acrylate having a hydroxyl group preferably contains hydroxyalkyl (meth) acrylate, more preferably 2-hydroxyethyl (meth) acrylate.

  Examples of the (meth) acrylate having an alkylene glycol chain include polyethylene such as diethylene glycol mono (meth) acrylate, triethylene glycol mono (meth) acrylate, tetraethylene glycol mono (meth) acrylate, and hexaethylene glycol mono (meth) acrylate. Glycol mono (meth) acrylate; Polypropylene glycol mono (meth) acrylate such as dipropylene glycol mono (meth) acrylate, tripropylene glycol mono (meth) acrylate, octapropylene glycol mono (meth) acrylate; Dibutylene glycol mono (meth) Polybutylene glycol mono (meth) acrylates such as acrylate and tributylene glycol mono (meth) acrylate; methoxy Liethylene glycol (meth) acrylate, methoxytetraethylene glycol (meth) acrylate, methoxyhexaethylene glycol (meth) acrylate, methoxyoctaethylene glycol (meth) acrylate, methoxynonaethylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate And alkoxy polyalkylene glycol (meth) acrylates such as methoxyheptapropylene glycol (meth) acrylate, ethoxytetraethylene glycol (meth) acrylate, butoxyethylene glycol (meth) acrylate, and butoxydiethylene glycol (meth) acrylate.

  Examples of the (meth) acrylate having an aromatic ring include benzyl (meth) acrylate and phenoxyethyl (meth) acrylate. Examples of the (meth) acrylate having an alicyclic group include cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, and dicyclopentanyl (meth) acrylate. Examples of (meth) acrylamide derivatives include N, N-dimethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, and N-isopropyl (meth). Examples include acrylamide, N, N-diethyl (meth) acrylamide, and N-hydroxyethyl (meth) acrylamide. Examples of the (meth) acrylate having an isocyanate group include 2- (2-methacryloyloxyethyloxy) ethyl isocyanate and 2- (meth) acryloyloxyethyl isocyanate.

  Examples of the siloxane compound having an ethylenically unsaturated group are compounds having an unsaturated group such as a (meth) acryloyl group, a styryl group, a cinnamic acid ester group, a vinyl group, and an allyl group, and a siloxane structure. . Examples of the siloxane compound having an ethylenically unsaturated group include compounds represented by the following general formula (a) or (b). A siloxane compound having an ethylenically unsaturated group may be used singly or in combination of two or more.

In formula (a), R ¹ represents a hydrogen atom or a methyl group, R ² , R ³ , R ⁴ , R ⁵ , R ⁶ and R ⁷ each independently represent a hydrogen atom or a methyl group, and R ⁸ represents 1 Represents a divalent hydrocarbon group, L ¹ represents a divalent hydrocarbon group or a single bond in which an oxygen atom may be interposed, and m represents an integer of 1 or more.

In formula (b), R ¹ represents a hydrogen atom or a methyl group, R ² , R ³ , R ⁴ , R ⁵ , R ⁶ and R ⁷ each independently represent a hydrogen atom or a methyl group, and L ¹ and L ² independently represents a divalent hydrocarbon group or a single bond in which an oxygen atom may intervene, and n represents an integer of 1 or more.

  Examples of the monovalent hydrocarbon group include an alkyl group having 1 to 6 carbon atoms or a phenyl group. As a bivalent hydrocarbon group, a C1-C20 alkylene group is mentioned, for example.

  Component (A) is composed of 50 to 90 parts by mass of a monomer unit derived from an alkyl (meth) acrylate having an alkyl group having 1 to 18 carbon atoms, 5 to a monomer unit derived from a (meth) acrylate having a hydroxyl group. It is preferable that 5-30 mass parts of monomer units derived from 30 mass parts and the siloxane compound which has an ethylenically unsaturated group are included.

  The content of the monomer unit derived from the alkyl (meth) acrylate having an alkyl group having 1 to 18 carbon atoms is preferably 50 to 90 mass with respect to 100 mass parts of all monomer units of the component (A). Parts, more preferably 60 to 90 parts by mass, and still more preferably 65 to 85 parts by mass. When the content of the monomer unit derived from the alkyl (meth) acrylate having an alkyl group having 1 to 18 carbon atoms is in such a range, when the resin layer is formed, the resin layer (impact absorbing layer) and It exists in the tendency which can improve adhesiveness with a base material more.

  The content of the monomer unit derived from the (meth) acrylate having a hydroxyl group is preferably 5 to 30 parts by mass, more preferably 10 to 30 parts per 100 parts by mass of the total monomer units of the component (A). Part by mass, more preferably 15 to 30 parts by mass. When the content of the monomer unit derived from the (meth) acrylate having a hydroxyl group is in such a range, the formed resin layer (impact absorbing layer) has high transparency (for example, haze of 5.0%). The following).

  The content of the monomer unit derived from the siloxane compound having an ethylenically unsaturated group is preferably 5 to 30 parts by mass, more preferably 5 to 100 parts by mass of the total monomer units of the component (A). -20 mass parts, More preferably, it is 5-15 mass parts. When the content of the monomer unit derived from the siloxane compound having an ethylenically unsaturated group is in such a range, the flexibility and toughness of the resulting resin layer can be improved, and higher impact resistance Tend to be able to get.

  Component (A) is a monomer unit derived from a (meth) acryloyl compound and a monomer unit derived from a siloxane compound having an ethylenically unsaturated group, as long as the effects of the present invention are not significantly impaired. A monomer unit derived from the other monomer may be further included. Examples of other monomers include acrylonitrile, styrene, vinyl acetate, ethylene, propylene, divinylbenzene, and the like.

  The weight average molecular weight (Mw) of the component (A) is preferably 300,000 to 1,500,000, more preferably 350,000 to 1,200,000, still more preferably 400,000 to 1,000,000. It is. When the weight average molecular weight (Mw) of the component (A) is 300,000 or more, the cohesiveness is increased and heat resistance tends to be easily obtained. When the weight average molecular weight (Mw) of the component (A) is 1,500,000 or less, a resin layer (impact absorbing layer) having a uniform thickness tends to be easily obtained when forming a film material. In addition, a weight average molecular weight (Mw) can be calculated | required from the value converted using the calibration curve of a standard polystyrene using gel permeation chromatography (GPC).

  The glass transition point (Tg) of the copolymer is preferably −75 to −30 ° C., more preferably −75 to −45 ° C., and further preferably −70 to −50 ° C. When the glass transition point (Tg) of the copolymer is −75 ° C. or higher, the cohesiveness is increased and good handling properties tend to be easily obtained. When the glass transition point (Tg) of the copolymer is −45 ° C. or lower, the flexibility of the resulting resin layer tends to be improved and high impact resistance tends to be imparted.

In addition, the glass transition point (Tg) of a copolymer means what was computed by the following relational expressions (FOX formula).
1 / Tg = Σ (X _i / Tg _i )
[In the above formula, Tg represents the glass transition point (K) of the copolymer. X _i represents a mass fraction of each monomer, and X ₁ + X ₂ +... + X _i +... + X _n = 1. Tg _i indicates the glass transition temperature (K) of a homopolymer of each monomer. ]

  The component (A) can be synthesized using a known polymerization method such as solution polymerization, emulsion polymerization, suspension polymerization, bulk polymerization, etc., but the component (A) can be synthesized by solution polymerization using an organic solvent. It is preferable to synthesize. A (meth) acrylate having a highly hydrophilic hydroxyl group and a siloxane compound having a highly hydrophobic ethylenically unsaturated group can be uniformly copolymerized by the effect of solvation, and in the resin layer (shock absorbing layer), High transparency (for example, haze of 5.0% or less) can be imparted.

  The organic solvent is not particularly limited, but an organic solvent that can dissolve each monomer is preferable. Examples of such organic solvents include aromatic hydrocarbons such as toluene and xylene, esters such as ethyl acetate and butyl acetate, aliphatic alcohols such as n-propyl alcohol and isopropyl alcohol, acetone, methyl ethyl ketone, and methyl. Examples thereof include ketones such as isobutyl ketone and cyclohexanone. Among these, the organic solvent is preferably ethyl acetate, methyl ethyl ketone, or toluene from the viewpoint of controlling the molecular weight of the copolymer.

  As the polymerization initiator for synthesizing the copolymer, a compound that generates a radical by heat can be used. Examples of the polymerization initiator include organic peroxides such as benzoyl peroxide and lauroyl peroxide; 2,2′-azobisisobutyronitrile, 2,2′-azobis (2-methylbutyronitrile), and the like. An azo compound is mentioned.

  The content of the component (A) is preferably 15 to 60% by mass, more preferably 15 to 55% by mass, and further preferably 15 to 50% by mass based on the total amount of the photocurable resin composition. When the content of the component (A) is 15% by mass or more based on the total amount of the photocurable resin composition, the toughness of the resulting resin layer tends to be improved. When the content of the component (A) is 60% by mass or less based on the total amount of the photocurable resin composition, the viscosity of the photocurable resin composition enters an appropriate viscosity range when producing the resin layer, Workability tends to be better.

(B) component: 2nd (meth) acryloyl compound The 2nd (meth) acryloyl compound which is (B) component is a compound which has one (meth) acryloyl group. Examples of the second (meth) acryloyl compound include the same compounds as those exemplified for the first (meth) acryloyl compound. The second (meth) acryloyl compound preferably includes an alkyl (meth) acrylate and a (meth) acrylate having a hydroxyl group.

  The content of the component (B) is preferably 40 to 85% by mass, more preferably 45 to 85% by mass, and further preferably 50 to 85% by mass based on the total amount of the photocurable resin composition. When the content of the component (B) is 40% by mass or more based on the total amount of the photocurable resin composition, the viscosity of the photocurable resin composition enters an appropriate viscosity range when the resin layer is produced, Workability tends to be better. When the content of the component (B) is 85% by mass or less based on the total amount of the photocurable resin composition, the toughness of the resulting resin layer tends to be improved.

Component (C): Photopolymerization initiator Component (C) promotes the curing reaction by irradiation with active energy rays. Active energy rays refer to ultraviolet rays, electron beams, α rays, β rays, γ rays and the like.

  Examples of the component (C) include benzophenone, N, N, N ′, N′-tetramethyl-4,4′-diaminobenzophenone (Michler ketone), N, N, N ′, N′-tetraethyl-4,4. '-Diaminobenzophenone, 4-methoxy-4'-dimethylaminobenzophenone, α-hydroxyisobutylphenone, 2-ethylanthraquinone, t-butylanthraquinone, 1,4-dimethylanthraquinone, 1-chloroanthraquinone, 2,3-dichloroanthraquinone , 3-chloro-2-methylanthraquinone, 1,2-benzoanthraquinone, 2-phenylanthraquinone, 1,4-naphthoquinone, 9,10-phenanthraquinone, thioxanthone, 2-chlorothioxanthone, 1-hydroxycyclohexyl phenyl ketone , 2,2- Aromatic ketone compounds such as methoxy-1,2-diphenylethane-1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 2,2-diethoxyacetophenone; benzoin, methylbenzoin, ethyl Benzoin compounds such as benzoin; benzoin ether compounds such as benzoin methyl ether, benzoin ethyl ether, benzoin isobutyl ether and benzoin phenyl ether; benzyl compounds such as benzyl and benzyldimethyl ketal; β- (acridin-9-yl) (meth) acryl Ester compounds such as acids; acridine compounds such as 9-phenylacridine, 9-pyridylacridine, 1,7-diacridinoheptane; 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, 2- ( o-black Phenyl) -4,5-di (m-methoxyphenyl) imidazole dimer, 2- (o-fluorophenyl) -4,5-diphenylimidazole dimer, 2- (o-methoxyphenyl) -4,5 -Diphenylimidazole dimer, 2- (p-methoxyphenyl) -4,5-diphenylimidazole dimer, 2,4-di (p-methoxyphenyl) 5-phenylimidazole dimer, 2- (2, 2,4,5-triarylimidazole dimers such as 4-dimethoxyphenyl) -4,5-diphenylimidazole dimer, 2- (p-methylmercaptophenyl) -4,5-diphenylimidazole dimer; 2-Benzyl-2-dimethylamino-1- (4-morpholinophenyl) -1-butanone; 2-methyl-1- [4- (methylthio) phenyl] -2- Ruphorino-1-propane; bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide; oligo (2-hydroxy-2-methyl-1- (4- (1-methylvinyl) phenyl) propanone) . These components (C) may be used alone or in combination of two or more.

  Examples of the component (C) that does not color the photocurable resin composition solution include 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, and 1- [4- ( Α-hydroxyalkylphenone compounds such as 2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one; bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, bis Acylphosphine oxide compounds such as (2,6-dimethoxybenzoyl) -2,4,4-trimethyl-pentylphosphine oxide, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide; oligo (2-hydroxy-2-methyl- 1- (4- (1-methylvinyl) phenyl) propanone) And the like.

  In order to form a particularly thick resin layer (shock absorbing layer), the component (C) includes, for example, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, bis (2,6-dimethoxybenzoyl)- Acylphosphine oxide compounds such as 2,4,4-trimethyl-pentylphosphine oxide and 2,4,6-trimethylbenzoyl-diphenylphosphine oxide may also be included.

  The content of the component (C) is preferably 0.05 to 5% by mass, more preferably 0.1 to 3% by mass, and still more preferably 0.1 to 1.% by mass, based on the total amount of the photocurable resin composition. 5% by mass. When the content of the photopolymerization initiator is 5% by mass or less, the transmittance is high, the hue is not yellowish, and a resin layer (impact absorbing layer) excellent in transparency tends to be obtained. It is in.

Other Components The photocurable resin composition may contain components other than the (A) component, the (B) component, and the (C) component as other components.

  Examples of other components include a photocrosslinking agent from the viewpoint of increasing the cohesive strength of the photocurable resin composition.

  Examples of the photocrosslinking agent include alkylene diol di (meth) acrylate having an alkylene group having 1 to 20 carbon atoms; alkylene glycol di (meth) acrylate such as polyethylene glycol di (meth) acrylate and polypropylene glycol di (meth) acrylate. Bisphenol type di (meth) acrylates such as ethoxylated bisphenol A di (meth) acrylate, ethoxylated bisphenol F di (meth) acrylate and bisphenol A type epoxy (meth) acrylate; urethane di (meth) acrylate having a urethane bond, etc. Can be mentioned.

  The urethane di (meth) acrylate having a urethane bond may have a polyalkylene glycol chain from the viewpoint of good compatibility with other components, and from the viewpoint of ensuring transparency, an alicyclic structure. You may have. When the compatibility between the photocrosslinking agent and the component (A) is low, the resin layer (shock absorbing layer) formed from the photocurable resin composition may become cloudy.

  From the viewpoint of further suppressing the occurrence of bubbles and peeling under high temperature or high temperature and high humidity, the weight average molecular weight of the photocrosslinking agent is preferably 100,000 or less, more preferably 300 to 100,000, and even more preferably 500 to 80. , 000.

  The content in the case of using the photocrosslinking agent is preferably 15% by mass or less, more preferably 10% by mass or less, and further preferably 7% by mass or less, based on the total mass of the component (A). Within such a range, a resin layer (shock absorbing layer) having sufficient adhesion tends to be obtained. The lower limit of the content of the photocrosslinking agent is not particularly limited, but is preferably 0.1% by mass or more, more preferably 2% by mass or more, and still more preferably 3% by mass from the viewpoint of improving film formability. That's it.

  As other components other than the photocrosslinking agent, for example, a polymerization inhibitor such as paramethoxyphenol added for the purpose of enhancing the storage stability of the photocurable resin composition, a photocurable resin composition is obtained by photocuring. Antioxidants such as triphenyl phosphite added for the purpose of increasing the heat resistance of the resin layer (shock absorbing layer), and HALS (Hindered Amine) for the purpose of increasing the resistance of the photocurable resin composition to light such as ultraviolet rays Light stabilizers such as Light Stabilizer), and silane coupling agents added to increase the adhesion of the photocurable resin composition to glass.

<Film material>
A film material according to an embodiment includes a resin layer and a pair of base material layers laminated so as to sandwich the resin layer, and the resin layer is used to form an impact absorption layer of an image display device. The said resin layer can be formed from the photocurable resin composition mentioned above.

  FIG. 2 is a cross-sectional view schematically showing an embodiment of the film material. As shown in FIG. 2, the film material 20 may include a resin layer 21, and one base material 22 and the other base material 23 stacked so as to sandwich the resin layer 21.

  The base material 22 is preferably a material that is more peelable than the base material 23. Examples of the base material 22 include polymer films such as polyethylene terephthalate (PET), polypropylene, and polyethylene. Among these, it is preferable that the base material 22 is a PET film. From the viewpoint of workability, the thickness of the base material 22 is preferably 50 to 200 μm, more preferably 60 to 150 μm, and still more preferably 70 to 130 μm.

  The planar shape of the base material 22 is larger than the planar shape of the resin layer 21, and the outer edge of the base material 22 preferably projects outward from the outer edge of the resin layer 21. The width at which the outer edge of the substrate 22 protrudes from the outer edge of the resin layer 21 is preferably 2 to 20 mm, more preferably 4 to 10 mm, from the viewpoint of ease of handling, ease of peeling, and reduction of adhesion of dust and the like. is there. When the planar shape of the resin layer 21 and the base material 22 is a substantially rectangular shape such as a substantially rectangular shape, the width at which the outer edge of the base material 22 protrudes from the outer edge of the resin layer 21 is preferably 2 on at least one side. -20 mm, more preferably 4 to 10 mm on at least one side, further preferably 2 to 20 mm on all sides, particularly preferably 4 to 10 mm on all sides.

  The base material 23 is preferably a light-peeling base material than the base material 22. Examples of the base material 23 include polymer films such as polyethylene terephthalate (PET), polypropylene, and polyethylene. Among these, it is preferable that the base material 23 is a PET film. From the viewpoint of workability, the thickness of the base material 23 is preferably 25 to 150 μm, more preferably 30 to 100 μm, and still more preferably 40 to 80 μm.

  The planar shape of the base material 23 is larger than the planar shape of the resin layer 21, and it is preferable that the outer edge of the base material 23 projects outward from the outer edge of the resin layer 21. The width at which the outer edge of the base material 23 protrudes from the outer edge of the resin layer 21 is preferably 2 to 20 mm, more preferably 4 to 10 mm, from the viewpoint of ease of handling, ease of peeling, and reduction of adhesion of dust and the like. is there. In the case where the planar shape of the resin layer 21 and the base material 23 is a substantially rectangular shape such as a substantially rectangular shape, the width at which the outer edge of the base material 23 protrudes from the outer edge of the resin layer 21 is preferably 2 on at least one side. -20 mm, more preferably 4 to 10 mm on at least one side, further preferably 2 to 20 mm on all sides, particularly preferably 4 to 10 mm on all sides.

  The peel strength between the base material 23 and the resin layer 21 is preferably lower than the peel strength between the base material 22 and the resin layer 21. As a result, the base material 22 is less likely to peel from the resin layer 21 than the base material 23. The peel strength can be adjusted, for example, by applying a surface treatment to the base material 22 and the base material 23. As the surface treatment method, for example, a release treatment of the base material with a silicone compound or a fluorine compound may be mentioned.

  A known technique can be used for forming the resin layer 21. For example, first, the viscosity of the above-mentioned photocurable resin composition is prepared depending on the content of the component (C) or the photocrosslinking agent. Next, the resin layer 21 having an arbitrary thickness is formed by applying the photocurable resin composition onto the base material 22 and irradiating the photocurable resin composition with active energy rays and curing the composition. be able to. As a coating method, for example, a known method such as a flow coating method, a roll coating method, a gravure coating method, a wire bar coating method, or a lip die coating method can be used.

  After forming the resin layer 21 on the base material 22, the base material 23 is laminated | stacked on the resin layer 21, and a film material is produced. The resin layer 21 is sandwiched between the base material 23 and the base material 22. In order to control the peelability between the resin layer 21 and the base material 23 and the base material 22, the copolymer solution is allowed to contain a surfactant such as a polydimethylsiloxane-based surfactant or a fluorine-based surfactant. Also good.

  The thickness of the resin layer 21 is not particularly limited because it is appropriately adjusted depending on the intended use and method, but may be 10 to 5000 μm, 25 to 200 μm, 25 to 180 μm, or 25 to 150 μm. When the thickness of the resin layer 21 is in such a range, the impact absorbing layer can be more resistant to an externally applied impact.

  The light transmittance of the resin layer 21 to light in the visible light region (wavelength: 380 nm to 780 nm) is preferably 80% or more, more preferably 90% or more, and still more preferably 95% or more.

The haze of the resin layer 21 is preferably 5% or less, more preferably 3% or less, and still more preferably 1% or less. Haze is a value (%) representing turbidity, and is a total transmittance T _{t of} light irradiated through a lamp and transmitted through a sample, and a transmittance of light diffused and scattered in the sample. From _Td, it is obtained as ( _Td / _Tt ) × 100. These are defined by JIS K 7136, and can be easily measured by a commercially available turbidimeter (for example, product name “NDH-5000” manufactured by Nippon Denshoku Industries Co., Ltd.).

  According to the film material which concerns on this embodiment, storage and conveyance can be made easy, without damaging the resin layer 21. FIG.

  The resin layer 21 can be used, for example, as an impact absorbing layer of an image display device by being disposed on one side or both sides of the image display member.

  Hereinafter, the present invention will be specifically described based on examples, but the present invention is not limited thereto.

<Synthesis of copolymer>
Production Example 1
In a reaction vessel equipped with a condenser, a thermometer, a stirrer, a dropping funnel, and a nitrogen introducing tube, 70.0 g of 2-ethylhexyl acrylate, 20.0 g of 2-hydroxyethyl acrylate, one-end methacryloyl-modified polysiloxane compound (Shin-Etsu Chemical) Kogyo Co., Ltd., product name “X-22-2426”, ethylenically unsaturated group equivalent: 12000 g / mol) 10.0 g, ethyl acetate 72.5 g, and methyl ethyl ketone 72.5 g are added, and the air volume is 100 mL / min. While replacing with nitrogen, the mixture was heated from room temperature (25 ° C.) to 65 ° C. in 30 minutes. Next, while maintaining the temperature at 65 ° C., a solution in which 0.1 g of lauroyl peroxide was dissolved in 5.0 g of ethyl acetate was added and reacted for 8 hours. Subsequently, ethyl acetate and methyl ethyl ketone were distilled off to obtain a copolymer A-1 (weight average molecular weight: 500,000, glass transition point: -68.5 ° C.).

Production Example 2
To the reaction vessel, add 70.0 g of n-butyl acrylate, 20.0 g of 2-hydroxyethyl acrylate, 10.0 g of the terminal methacryloyl-modified polysiloxane compound used in Production Example 1, 72.5 g of ethyl acetate, and 72.5 g of methyl ethyl ketone. Except that, copolymer A-2 (weight average molecular weight: 500,000, glass transition point: -57.4 ° C.) was obtained in the same manner as in Production Example 1.

Production Example 3
In a reaction vessel, 70.0 g of n-butyl acrylate, 25.0 g of 2-hydroxyethyl acrylate, 5.0 g of one-end methacryloyl-modified polysiloxane compound used in Production Example 1, 72.5 g of ethyl acetate, and 72.5 g of methyl ethyl ketone. A copolymer A-3 (weight average molecular weight: 500,000, glass transition point: −50.7 ° C.) was obtained in the same manner as in Production Example 1 except for the addition.

Production Example 4
To the reaction vessel, add 70.0 g of isostearyl acrylate, 20.0 g of 2-hydroxyethyl acrylate, 10.0 g of one-end methacryloyl-modified polysiloxane compound used in Production Example 1, 72.5 g of ethyl acetate, and 72.5 g of methyl ethyl ketone. Except that, copolymer A-4 (weight average molecular weight: 500,000, glass transition point: −32.3 ° C.) was obtained in the same manner as in Production Example 1.

Production Example 5
A copolymer was prepared in the same manner as in Production Example 1 except that 80.0 g of 2-ethylhexyl acrylate, 20.0 g of 2-hydroxyethyl acrylate, 72.5 g of ethyl acetate, and 72.5 g of methyl ethyl ketone were added to the reaction vessel. A-5 (weight average molecular weight: 500,000, glass transition point: -61.0 ° C.) was obtained.

Production Example 6
A copolymer was prepared in the same manner as in Production Example 1 except that 80.0 g of n-butyl acrylate, 20.0 g of 2-hydroxyethyl acrylate, 72.5 g of ethyl acetate, and 72.5 g of methyl ethyl ketone were added to the reaction vessel. A-6 (weight average molecular weight: 500,000, glass transition point: −47.2 ° C.) was obtained.

  The weight average molecular weight is determined by conversion using a standard polystyrene calibration curve using gel permeation chromatography (GPC) using tetrahydrofuran (THF) as a solvent and the following apparatus and measurement conditions. It was. In preparing the calibration curve, 5 sample sets (PStQuick MP-H, PStQuick B (manufactured by Tosoh Corporation, product name)) were used as standard polystyrene.

Device: High-speed GPC device HLC-8320GPC (detector: differential refractometer)
(Product name, manufactured by Tosoh Corporation)
Solvent: Tetrahydrofuran (THF)
Column: Column TSKgel SuperMultipore HZ-H
(Product name, manufactured by Tosoh Corporation)
Column size: Column length is 15 cm, column inner diameter is 4.6 mm
Measurement temperature: 40 ° C
Flow rate: 0.35 mL / min
Sample concentration: 10 mg / THF 5 mL
Injection volume: 20 μL

<Preparation of photocurable resin composition and production of film material>
The following components were prepared for the preparation of the photocurable resin composition.
Component (A): Copolymers A-1 to A-6
Component (B): 2-ethylhexyl acrylate (2EHA)
: Hydroxyethyl acrylate (HEA)
Component (C): 1-hydroxycyclohexyl phenyl ketone (I-184)
(Product name “Irgacure-184” manufactured by BASF)
: 4-methylbenzophenone (4MBP)
(Product name "SB-PI712" manufactured by Sort Corporation)

Example 1
Copolymer A-1 obtained in Production Example 1 25.0 parts by mass, 2-ethylhexyl acrylate (2EHA) 63.8 parts by mass, hydroxyethyl acrylate (HEA) 11.3 parts by mass, 1-hydroxycyclohexyl phenyl ketone (I-184) 0.5 parts by mass and 4-methylbenzophenone (4MBP) 0.3 parts by mass, and stirring and mixing them, the photocuring of Example 1 which is liquid at room temperature (25 ° C.) A functional resin composition was obtained.

Next, an applicator is used on a 75 μm-thick polyethylene terephthalate (PET) film (base film A) having a release treatment on the surface so that the thickness of the resin composition after the ultraviolet irradiation is 100 μm. A coating film is formed by coating, and a 50 μm-thick polyethylene terephthalate (PET) film (base film B) having a release treatment is placed on the formed coating film, and an ultraviolet irradiation device (manufactured by Eye Graphics Co., Ltd.). ) Was used for ultraviolet irradiation (2,000 mJ / cm ² ) to produce the film material of Example 1.

Examples 2 to 4 and Comparative Examples 1 and 2
Except having changed the compounding quantity of each component into what is shown in Table 1, it carried out similarly to Example 1, and produced the film material of Examples 2-4 and Comparative Examples 1 and 2. FIG. In Table 1, the unit of the numerical value of the amount is mass parts.

<Evaluation>
About the film material obtained by each Example and the comparative example, it evaluated by the following method. The results are shown in Table 1.

1. Measurement of Acceleration Decay Rate FIG. 3 is a schematic diagram schematically showing an example of an acceleration decay rate measurement device. The acceleration attenuation rate measuring device 30 shown in FIG. 3 mainly supports the resin layer 31 provided in the film material, a fixing plate 32 (polymethyl methacrylate plate) for attaching the resin layer 31, and the fixing plate 32. The metal plate 33, a hammer 35 having an iron ball 34, and an acceleration sensor 36 disposed at the tip of the hammer 35 opposite to the iron ball 34 are configured.

The film materials of Examples 1 to 4 and Comparative Examples 1 and 2 were cut into a size of 50 mm × 50 mm, and the base film B of the cut film material was peeled off to expose the surface of the resin layer 31. Thereafter, the exposed surface of the resin layer 31 was attached to a fixing plate 32 (length 100 mm × width 100 mm × thickness 3.0 mm) and pressed with a roller. Next, the base film A is peeled off from the resin layer 31 attached to the fixing plate 32, the surface of the resin layer 31 is exposed, and the fixing plate 32 and the metal plate 33 (length 150 mm × width 150 mm × thickness 10 mm) are in contact with each other. A measurement sample was obtained by placing in Next, a hammer 35 (mass 280 g) to which an iron ball 34 having a diameter of 11 mm is fixed is dropped from a position 20 mm in height in the vertical direction from the resin layer 31 of the measurement sample, and the acceleration sensor 36 (product of Showa Keiki Co., Ltd., product) The peak acceleration was measured using the name “MODEL-1340B”). The peak acceleration is obtained by reading the peak value (impact acceleration) from the waveform in which the absolute value is detected when the peak hold function built in the acceleration sensor is used. The measurement was performed in an environment of 23 ° C. The acceleration decay rate was calculated based on the following formula (A). The “peak acceleration when no resin layer is provided” in the formula (A) means a peak acceleration when measured only by the fixed plate 32 without providing the resin layer 31.
Acceleration decay rate (%)
= (Peak acceleration when not provided a resin layer [m / s 2] ^- peak acceleration when the resin layer is provided [m / s ^{2]) /} a If no resin layer provided peak acceleration [m / s ² ] × 100 (A)

2. Measurement of Haze The film materials of Examples 1 to 4 and Comparative Examples 1 and 2 were cut into a size of 50 mm × 50 mm, and the base film B of the cut film material was peeled to expose the surface of the resin layer. Thereafter, the surface of the exposed resin layer of the film material was attached to float glass (length 50 mm × width 50 mm × thickness 2.7 mm) and pressed with a roller. Next, the base film A is peeled off from the resin layer attached to the float glass, and the surface of the resin layer is float glass (length 50 mm × width 50 mm × thickness 2.7 mm) in a vacuum state using a vacuum laminator. The laminated body was produced by pasting. Then, the produced laminated body was heat-pressed (autoclave process) on the conditions hold | maintained for 30 minutes with the temperature of 50 degreeC, the pressure of 0.5 MPa, and the measurement sample was obtained. About the obtained sample, haze was measured based on the following formula (B) according to JIS K7361 using a turbidimeter (Nippon Denshoku Industries Co., Ltd., product name "NDH-5000").
Haze (%) = (Td / Tt) × 100 (B)
Td: diffuse transmittance, Tt: total light transmittance

  The resin layer of the film material of Examples 1-4 produced using the photocurable resin composition of Examples 1-4 is Comparative Example 1 produced using the photocurable resin composition of Comparative Examples 1 and 2. Compared with the resin layer of 2 film material, it was excellent in impact resistance. From this, it was suggested that when the resin layer of the film material of Examples 1 to 4 is applied to an image display device, it can act as an impact absorbing layer.

  DESCRIPTION OF SYMBOLS 10 ... Image display apparatus, 11 ... Shock absorption layer, 12 ... Board | substrate, 13 ... Image display member, 14 ... Function improvement member, 15 ... Barrier member, 20 ... Film material, 21 ... Resin layer, 22, 23 ... Base material DESCRIPTION OF SYMBOLS 30 ... Acceleration decay rate measuring apparatus, 31 ... Resin layer, 32 ... Fixed plate, 33 ... Metal plate, 34 ... Iron ball, 35 ... Hammer, 36 ... Acceleration sensor

Claims (10)

An image display member, and a shock absorbing layer disposed on one or both sides of the image display member,
The shock absorbing layer is
A copolymer comprising a monomer unit derived from a first (meth) acryloyl compound and a monomer unit derived from a siloxane compound having an ethylenically unsaturated group;
A second (meth) acryloyl compound;
A photopolymerization initiator;
The image display apparatus which is a hardened | cured material of the photocurable resin composition containing this.   The image display apparatus according to claim 1, wherein the first (meth) acryloyl compound includes an alkyl (meth) acrylate having an alkyl group having 1 to 18 carbon atoms and a (meth) acrylate having a hydroxyl group.   50 to 90 parts by mass of monomer units derived from an alkyl (meth) acrylate having an alkyl group having 1 to 18 carbon atoms, and 5 to monomer units derived from a (meth) acrylate having a hydroxyl group. The image display apparatus according to claim 2, comprising 30 to 30 parts by mass and 5 to 30 parts by mass of a monomer unit derived from a siloxane compound having an ethylenically unsaturated group. A copolymer comprising a monomer unit derived from a first (meth) acryloyl compound and a monomer unit derived from a siloxane compound having an ethylenically unsaturated group;
A second (meth) acryloyl compound;
A photopolymerization initiator,
A photocurable resin composition used for forming a shock absorbing layer of an image display device.   The photocurable resin composition according to claim 4, wherein the first (meth) acryloyl compound includes a (meth) acryloyl compound having a C 1-18 alkyl group and a (meth) acryloyl compound having a hydroxyl group. .   50 to 90 parts by mass of monomer units derived from an alkyl (meth) acrylate having an alkyl group having 1 to 18 carbon atoms, and 5 to monomer units derived from a (meth) acrylate having a hydroxyl group. The photocurable resin composition of Claim 5 containing 30-30 mass parts and 5-30 mass parts of monomer units derived from the siloxane compound which has an ethylenically unsaturated group. A film material comprising a resin layer and a pair of base material layers laminated so as to sandwich the resin layer, wherein the resin layer is used to form a shock absorbing layer of an image display device,
The resin layer is
A copolymer comprising a monomer unit derived from a first (meth) acryloyl compound and a monomer unit derived from a siloxane compound having an ethylenically unsaturated group;
A second (meth) acryloyl compound;
A photopolymerization initiator;
A film material which is a cured product of a photocurable resin composition containing   The film material according to claim 7, wherein the first (meth) acryloyl compound includes an alkyl (meth) acrylate having an alkyl group having 1 to 18 carbon atoms and a (meth) acrylate having a hydroxyl group.   50 to 90 parts by mass of monomer units derived from an alkyl (meth) acrylate having an alkyl group having 1 to 18 carbon atoms, and 5 to monomer units derived from a (meth) acrylate having a hydroxyl group. The film material according to claim 8, comprising 5 to 30 parts by mass of monomer units derived from 30 parts by mass and a siloxane compound having an ethylenically unsaturated group.   The film material as described in any one of Claims 7-9 whose haze of the said resin layer is 5% or less.

Images