JP2013184997A - Liquid photocurable resin composition, image display device using the same, and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid photocurable resin composition whose portions which no light has struck on can be cured when the composition is irradiated and cured with light, without using a metallocene complex and carrying out a light irradiation step before casting and coating, and which can provide a cured material having high transparency by curing; and to provide an image display device using the same, and to provide a method of manufacturing the same.SOLUTION: A liquid photocurable resin composition contains an ethylenically unsaturated bond-containing component (1) containing a polymer (A) having a methacryloyl group on its side chain, and a photopolymerization initiator (2), wherein the photopolymerization initiator (2) exhibits a maximum absorption wavelength in the range of 370 to 420 nm.

Description

  The present invention relates to a liquid photocurable resin composition capable of curing a portion that is not directly exposed to light when cured by irradiation with light, and capable of obtaining a highly transparent cured product by curing. The present invention also relates to an image display device using the cured product of the liquid photocurable resin composition and a method for producing the same.

In general, when a photocurable resin composition is irradiated with light (such as ultraviolet rays), an active radical or an acid is generated from a polymerization initiator, and a polymerizable compound is polymerized. However, dark parts where light does not reach, such as shadows and narrow gaps, are not cured. Therefore, when using a photocurable resin composition as an adhesive agent, there exists a problem that an adherend is restrict | limited to a transparent thing. In addition, when the photocurable resin composition is cast into a mold having a complicated shape and irradiated with light to obtain a cast product, there is a problem that a part of the cast product may not be sufficiently cured.
In order to solve these problems, a dark reaction curable resin composition is used. Here, “dark reaction curability” refers to the property that once the light is irradiated to induce the reaction curability of the composition, the polymerization reaction is maintained even when the light irradiation is stopped.

For example, Patent Document 1 discloses that an ultraviolet curable resin composition composed of an epoxy resin and a cationic polymerization catalyst is uniformly irradiated with ultraviolet rays in a state of being preliminarily accommodated in a glass tube, and then cast or applied. It is described to do.
In Patent Document 2, a dark reaction curable composition containing a polymerizable compound having an unsaturated double bond, a sulfimide compound, an amine compound, and a metallocene complex is preliminarily irradiated with light and then adhered to an adherend. It is described that the curing reaction is allowed to proceed by making an anaerobic state.

Japanese Patent Publication No. 4-26333 Japanese Patent Laid-Open No. 11-5014

If the dark reactive resin composition described in Patent Document 1 is rapidly cured while being uniformly irradiated with ultraviolet rays in a state of being accommodated in a glass capillary, a cured product is obtained. Since it cannot flow out of the narrow tube, it is necessary to slow down the curing reaction, and there is a problem that it takes a long time for curing.
Further, the dark reactive resin composition described in Patent Document 2 needs to use many components such as a metallocene complex in order to impart dark reaction curability, and if it is not anaerobic, the curing reaction is sufficient. There is also a problem that it doesn't progress.
Furthermore, the resin composition of Patent Documents 1 and 2 needs to be subjected to a process of uniformly irradiating the resin composition with light, for example, by pre-contained in a glass tube as a pre-process of casting or coating. Yes, it is complicated.
On the other hand, when a curable resin composition is interposed between a protective panel such as an image display device and the touch panel, the curable resin composition has an appropriate dielectric constant within the range of 1 to 5 from the viewpoint of the operability of the touch panel. It is required to be. If the dielectric constant is less than 1, the response of the touch panel tends to decrease. If the dielectric constant exceeds 5, the response becomes too high and may malfunction.

  The present invention has been made in view of the above, and light is directly applied when cured by irradiating light without using a metallocene complex or performing a light irradiation step before casting or coating. An object of the present invention is to provide a photocurable resin composition capable of curing a non-contact portion and having an appropriate dielectric constant, an image display device using the photocurable resin composition, and a method for producing the same. It is what.

As a result of intensive research to achieve the above object, the inventors of the present invention are liquid photocurable resin compositions containing a specific ethylenically unsaturated bond-containing component and a photopolymerization initiator, and the photopolymerization initiation If the agent has a maximum absorption wavelength in the range of 370 to 420 nm, the shadow portion, narrow gap portion (sometimes referred to as “light-shielding portion”) can be cured well, and it has an appropriate dielectric constant. I found it.
The present invention has been completed based on such findings.

That is, the present invention relates to the following [1] to [12].
[1] A liquid photocurable resin composition comprising an ethylenically unsaturated bond-containing component (1) containing a polymer (A) having a (meth) acryloyl group in the side chain, and a photopolymerization initiator (2). And
A liquid photocurable resin composition in which the photopolymerization initiator (2) has a maximum absorption wavelength in a range of 370 to 420 nm.
[2] The liquid photocurable resin composition according to [1], further including a phosphor (3).
[3] The liquid photocurable resin composition according to [2], wherein the phosphor (3) is at least one selected from the group consisting of pyrene, benzopyrene, perylene, anthracene, naphthalene, phenanthrene, and coumarin.
[4] The liquid photocurable resin composition according to any one of [1] to [3], further including a thiol compound (4).
[5] The liquid photocurable resin according to any one of [1] to [4], wherein the polymer (A) having a (meth) acryloyl group in the side chain is an acrylic polymer having a (meth) acryloyl group. Composition.
[6] For filling a gap between an image display unit having an image display unit and a protective panel having a light shielding portion along the outer peripheral edge, or a gap between the touch panel and a protective panel having a light shielding portion along the outer peripheral edge. ] The liquid photocurable resin composition of any one of [5].
[7] An image display device having a layer formed from the liquid photocurable resin composition according to any one of [1] to [5] on the viewing side.
[8] The layer formed from the liquid photocurable resin composition according to any one of [1] to [5] is provided between the viewing-side protection plate and the image display panel, and between the viewing-side protection plate and The image display device according to [7], which is formed between the touch panel and between the touch panel and the image display panel.
[9] A sheet obtained by curing the liquid photocurable resin composition according to any one of [1] to [5] into a sheet is any of polymethyl methacrylate, polyethylene terephthalate, polycarbonate, and polarizing plate. An image display device in contact with a layer containing
[10] An image display having a laminated structure including an image display unit having an image display unit, a protective panel having a light-shielding unit along an outer periphery, and a resin layer existing between the image display unit and the protective panel. It is an apparatus, Comprising: The said resin layer is an image display apparatus which is a hardened | cured material of the liquid photocurable resin composition of any one of [1]-[6].
[11] An image display having a laminated structure including an image display unit having an image display unit, a touch panel, a protective panel having a light-shielding unit along the outer periphery, and a resin layer existing between the touch panel and the protective panel. It is an apparatus, Comprising: The said resin layer is an apparatus for image displays which is a hardened | cured material of the liquid photocurable resin composition of any one of [1]-[6].
[12] An image display unit or touch panel having an image display unit and a protective panel having a light-shielding unit along the outer periphery are disposed to face each other, and the liquid photocurable resin composition is interposed between the liquid photocurable resin compositions. A method for producing an image display device for curing a curable resin composition, wherein the liquid photocurable resin composition according to any one of [1] to [6] is interposed in the gap, and at least the protective panel. A method of manufacturing an image display device that is cured by light irradiation from the surface side.

  According to the present invention, it is possible to cure a shadow part, a narrow gap part, etc. (light-shielding part) satisfactorily without using a metallocene complex or performing a light irradiation process before casting or coating. A liquid photocurable resin composition capable of obtaining a cured product having an appropriate dielectric constant upon curing can be provided, an optical member, an image display device using the liquid photocurable resin composition, and a method for producing the device Can be provided.

It is side surface sectional drawing which shows typically one Embodiment of a liquid crystal display device. It is side surface sectional drawing which shows typically embodiment of another liquid crystal display device.

Hereinafter, the present invention will be described in detail.
In this specification, “(meth) acrylate” means “acrylate” and “methacrylate” corresponding thereto. Similarly, “(meth) acryl” means “acryl” and “methacryl” corresponding thereto, and “(meth) acryloyl” means “acryloyl” and corresponding “methacryloyl”.
“Liquid” means liquid at room temperature (25 ° C.).

[Liquid photocurable resin composition]
The liquid photocurable resin composition of the present invention comprises an ethylenically unsaturated bond-containing component (1) containing a polymer (A) having a (meth) acryloyl group in the side chain, and a photopolymerization initiator (2). It is a liquid photocurable resin composition, Comprising: A photoinitiator (2) has a maximum absorption wavelength in the range of 370-420 nm.
According to the liquid photocurable resin composition of the present invention, the light-shielding part can be cured well with light scattered from the irradiation light to the light-shielding part such as a shadow part or a narrow gap part.
Therefore, the liquid photocurable resin composition of the present invention is suitably used for filling a gap between an image display unit having an image display unit and a protective panel having a light shielding unit along the outer peripheral edge.

<Ethylenically unsaturated bond-containing component (1)>
The ethylenically unsaturated bond-containing component (1) contains a polymer (A) having a (meth) acryloyl group in the side chain, but if necessary, a compound having a (meth) acryloyl group other than the component (A) ( B) may be included.
This ethylenically unsaturated bond-containing component (1) has a transmittance of 90% for the ethylenically unsaturated bond-containing component (1) at the maximum absorption wavelength existing in the range of 370 to 420 nm of the photopolymerization initiator (2). That's it.
First, each component of the ethylenically unsaturated bond-containing component (1) will be described, and then the properties of the ethylenically unsaturated bond-containing component (1) containing these components will be described.

(Polymer (A) having (meth) acryloyl group in side chain)
(A) component:
The polymer (A) having a (meth) acryloyl group in the side chain in the present invention is, for example, an acrylic polymer (a1) in which the side chain is modified with a (meth) acryloyl group, and an isoprene in which the side chain is modified with a (meth) acryloyl group. A polymer (a2) etc. are mentioned.
The acrylic polymer (a1) obtained by modifying the side chain with a (meth) acryloyl group preferably has a structural unit represented by the following general formula (1) and a structural unit represented by the following general formula (2).
As a method of modifying the side chain by (meth) acryl, for example, a structural unit having a hydroxyl group or a structural unit having a carboxyl group represented by the following general formula (3) in the component (A) is incorporated in the main chain of the polymer. There is a method of adding (meth) acrylate having an isocyanate group such as 2-isocyanatoethyl (meth) acrylate represented by the following general formula (4). Further, as another method, for example, there is a method in which a structural unit having a glycidyl group as represented by the following general formula (5) is provided in the main chain of the polymer and (meth) acrylic acid is added thereto. Can be mentioned. Furthermore, although the method of forming a (meth) acryl side chain by graft polymerization is also mentioned, it has isocyanate groups, such as 2-isocyanatoethyl (meth) acrylate, in the hydroxyl group as shown by following General formula (3) ( A method of adding (meth) acrylate or a method of adding (meth) acrylic acid to a glycidyl group as shown by the following general formula (5) is more preferable.
When a (meth) acrylate having an isocyanate group is added to a hydroxyl group represented by the following general formula (3), the (meth) acrylate having an isocyanate group is added in an amount of 0.01 to 0. It is preferable to add such that the ratio is 9 equivalents. Similarly, when (meth) acrylic acid is added to a glycidyl group as represented by the following general formula (5), a ratio of 0.01 to 0.9 equivalent of (meth) acrylic acid to 1 equivalent of glycidyl group It is preferable to add such that
According to these methods, a structure in which the side chain (meth) acryloyl group is bonded to the main chain via a urethane bond or an ester bond is obtained. These structures are preferable from the viewpoints of impact absorption, low dielectric constant and the like.

(In the general formulas (1) and (2), R represents hydrogen or a methyl group, R ¹ represents an alkyl group having 4 to 18 carbon atoms or an alicyclic alkyl group, and X represents —CH ₂ CH _2. —, — (CH ₂ CH ₂ O) _p CH ₂ CH ₂ — {p is an integer from 1 to 500}, —R ² —OCONH—R ³ — or —R ⁴ —CH (OH) CH ₂ —. , R ² , R ³ and R ⁴ each independently represents an alkylene group having 1 to 10 carbon atoms or an alicyclic alkylene group.

(In general formula (3), R represents hydrogen or a methyl group, and R ² represents an alkylene group having 1 to 10 carbon atoms or an alicyclic alkylene group.)

(In General Formula (4), R represents hydrogen or a methyl group, and R ³ represents an alkylene group having 1 to 10 carbon atoms or an alicyclic alkylene group.)

(In general formula (5), R represents hydrogen or a methyl group, and R ⁴ represents an alkylene group having 1 to 10 carbon atoms or an alicyclic alkylene group.)
In the acrylic polymer (a1) in which the side chain is modified with a (meth) acryloyl group, it is preferable that the general formula (1) is mainly included.
R ¹ is preferably an alkyl group having 8 to 12 carbon atoms, and a dodecyl group (sometimes referred to as lauryl group) is preferable from the viewpoint of reducing the dielectric constant.
On the other hand, examples of the isoprene polymer having the (a2) (meth) acryloyl group include compounds represented by the following general formula (6).

一般式（６）中、ｍは５０〜１０００の数を示し、ｎは１〜５の数を示し、Ｒ^１は水素原子またはメチル基を示す。ｍは１００〜８００が好ましく、１５０〜７００がより好ましく、２００〜６００が更に好ましい。ｎは１．５〜４が好ましく、２〜３．５がより好ましく、２〜３が更に好ましい。
前記一般式（６）で表される化合物は、ＵＣ１０２、ＵＣ２０３（株式会社クラレ製）として商業的に入手可能である。
低誘電率及び低硬化収縮率の観点からは、（ａ１）と（ａ２）を併用することが好ましい。

In the general formula (6), m is a number of 50 to 1000, n is a number of 1 to 5, ^{R 1} represents a hydrogen atom or a methyl group. m is preferably 100 to 800, more preferably 150 to 700, and still more preferably 200 to 600. n is preferably 1.5 to 4, more preferably 2 to 3.5, and still more preferably 2 to 3.
The compound represented by the general formula (6) is commercially available as UC102 and UC203 (manufactured by Kuraray Co., Ltd.).
From the viewpoint of low dielectric constant and low curing shrinkage, it is preferable to use (a1) and (a2) in combination.

  Specifically, the weight average molecular weight of the component (A) is preferably 3,000 to 300,000, more preferably 5,000 to 100,000, and still more preferably 5,000 to 50,000.

In the present specification, the weight average molecular weight can be measured by gel permeation chromatography (GPC) under the following conditions.
(GPC conditions)
Measuring instrument: HLC-8320GPC [Tosoh Corporation]
Analytical column: TSKgel SuperMultipore HZ-H (3 linked)
[Tosoh Corporation]
Guard column: TSK guard column SuperMP (HZ) -H [Tosoh Corporation]
Eluent: THF
Measurement temperature: 25 ° C
The weight average molecular weight (Mw) is defined as follows assuming that there are N _i molecules having a molecular weight M _i .
Mw = Σ (N _i M _i ² ) / ΣN _i M _i = ΣW _i M _i
(W _i = weight fraction of molecules of molecular weight M _i = N _i M _i / ΣN _i M _i )

[Content of polymer (A) having (meth) acryloyl group in side chain]
60-100 mass% is preferable with respect to the total amount of an ethylenically unsaturated bond containing component (1), and, as for content of the polymer (A) which has a (meth) acryloyl group in a side chain, 75-100 mass% is more. Preferably, 80 to 100% by mass is more preferable. When it is 60% by mass or more, the curing shrinkage becomes good (the curing shrinkage rate is reduced).

(Compound (B) having a (meth) acryloyl group other than the component (A))
The liquid photocurable resin composition of the present invention may contain a compound (B) having a (meth) acryloyl group other than the component (A) as the ethylenically unsaturated bond-containing component (1).
As the compound (B) having a (meth) acryloyl group other than the component (A), for example, a monomer (b1) having one (meth) acryloyl group in the molecule, two or more ( And a monomer (b2) having a (meth) acryloyl group.
[Monomer (b1) having one (meth) acryloyl group in the molecule]
As the monomer (b1) having one ethylenically unsaturated group in the molecule, acrylic acid, methacrylic acid, and derivatives thereof (hereinafter sometimes referred to as (meth) acrylic acid derivatives) are preferable. Can be mentioned.

Specifically, as the monomer (b1) having one ethylenically unsaturated group in the molecule (hereinafter sometimes referred to as the (b1) component), methyl (meth) acrylate, n-butyl (meta ) Acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isononyl (meth) acrylate, n-octyl (meth) acrylate, lauryl (meth) acrylate, alkyl (meth) acrylate such as stearyl (meth) acrylate, Aralkyl (meth) acrylates such as benzyl (meth) acrylate, alkoxyalkyl (meth) acrylates such as butoxyethyl (meth) acrylate, aminoalkyl (meth) acrylates such as N, N-dimethylaminoethyl (meth) acrylate, diethylene glycol ethyl A (Meth) acrylic acid esters of polyalkylene glycol alkyl ethers such as (meth) acrylic acid esters of triethylene glycol butyl ether, (meth) acrylic acid esters of dipropylene glycol methyl ether, hexaethylene Alkylphenoxy having 4 to 12 carbon atoms in the alkyl group such as (meth) acrylic acid ester of polyalkylene glycol aryl ether such as (meth) acrylic acid ester of glycol phenyl ether and (meth) acrylic acid ester of nonylphenoxypolyethylene glycol (Meth) acrylic acid ester of polyethylene glycol (average value of ethylene glycol structural unit is 1 to 20), cyclohexyl (meth) acrylate, dicyclopentanyl (meth) acrylate Rate, isobornyl (meth) acrylate, (meth) acrylic acid ester having an alicyclic group such as methoxylated cyclodecatriene (meth) acrylate, fluorinated alkyl (meth) acrylate such as heptadecafluorodecyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, (meth) acrylic acid ester having a hydroxyl group such as glycerol mono (meth) acrylate, glycidyl (meth) acrylate (Meth) acrylic acid ester having a glycidyl group such as (meth) acrylic acid, (meth) acrylamide, (meth) acryloylmorpholine and the like. From the viewpoint of further reducing the curing shrinkage rate, an alkylphenoxypolyethylene glycol (meth) acrylic acid ester having an alkyl group having 4 to 12 carbon atoms (average of ethylene glycol structural units is 1 to 20) is preferable. In addition, from the viewpoint of wet heat resistance and workability during coating, (meth) acrylic acid ester having a hydroxyl group and (meth) acryloylmorpholine are preferable.
The monomer (b1) having one ethylenically unsaturated group in these molecules can be used alone or in combination of two or more.

  In addition to or instead of the above (meth) acrylic acid derivative, use a monomer having one ethylenically unsaturated bond in the molecule such as (meth) acrylonitrile, styrene, vinyl acetate, ethylene, propylene. However, (meth) acrylic acid derivatives are preferred.

[Monomer (b2) having two or more ethylenically unsaturated groups in the molecule]
Monomer (b2) (hereinafter referred to as component (b2) having two or more ethylenically unsaturated bonds in the molecule together with the monomer (b1) having one ethylenically unsaturated group in the molecule. Can be used).

  In the case of using a monomer (b2) having two or more ethylenically unsaturated groups in the molecule, a monomer having an ethylenically unsaturated group in the molecule from the viewpoint of curability, adhesion and curing shrinkage. The content of the monomer (b2) having two or more ethylenically unsaturated groups in the molecule in the body (B) is preferably 0.1 to 20% by mass, more preferably 0.5 to 10% by mass. Preferably, 1-5 mass% is still more preferable.

  As the monomer (b2) having two or more ethylenically unsaturated groups in the molecule, as in the case of the monomer (b1) having one ethylenically unsaturated group in the molecule, acrylic acid is used. , Methacrylic acid, and derivatives thereof ((meth) acrylic acid derivatives) are preferred.

  Examples of the monomer (b2) having two or more ethylenically unsaturated bonds in the molecule include bisphenol A di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,3- Butylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, glycerol di (meth) acrylate, neopentyl glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, tetraethylene glycol Di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, tris ((meth) acryloxyethyl) isocyanurate, pentaerythritol tetra (meth) Acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta (meth) acrylate.

  Examples of the monomer (b2) having two or more ethylenically unsaturated bonds in the molecule further include the general formula (a)

(However, In the formula (a), ^{R 1} and ^{R 2} each independently represents an ethylene group or a propylene group, m and n each independently represent an integer of 1 to 5, m and n are each 2 In the above case, a plurality of R ¹ -Os may be the same or different, and a plurality of R ² -Os may be the same or different.) Diacrylate of an alkylene oxide adduct of bisphenol A, Formula (b)

(However, in general formula (b), a and b each represent 1) An epichlorohydrin modified product of bisphenol A and an acrylic ester addition product, general formula (c)

(However, in general formula (c), R < ³ > and R < ⁴ > show an ethylene group or a propylene group each independently, c and d show the integer of 1-5 each independently, and c and d are 2 respectively. In the above case, a plurality of R ³ —O may be the same or different, and a plurality of R ⁴ —O may be the same or different.) Formula (d)

(In the general formula (d), e and f each represent 1) An epichlorohydrin-modified product of phthalic acid and an addition esterified product of acrylic acid represented by the general formula (e)

(However, in general formula (e), g and h are 1) 1,6-hexanediol epichlorohydrin modified product and acrylic acid addition esterified product (having two acrylic groups in one molecule) ), General formula (f)

(However, in general formula (f), R < ⁶ > shows an ethylene group or a propylene group, 3 i shows the integer of 1-5 each independently, and when i is 2 or more, several R < ⁶ >- O may be the same or different.) Triacrylate of alkylene oxide adduct of phosphoric acid represented by general formula (g)

(However, in general formula (g), R < ⁶ >, R < ⁷ > and R < ⁸ > show an ethylene group or a propylene group each independently, j, k, and p show each independently the integer of 1-3, j , K and p are each 2 or more, a plurality of R ⁶ —O, R ⁷ —O and R ⁸ —O may be the same or different from each other.) And triacrylate of the above.
In addition to or in place of the above (meth) acrylic acid derivative, a monomer (divinylbenzene or the like) having two or more other ethylenically unsaturated bonds in the molecule can also be used. ) Acrylic acid derivatives are preferred.
The monomer (b2) having two or more ethylenically unsaturated bonds in these molecules can be used alone or in combination of two or more.
The content of the monomer (B) having an ethylenically unsaturated group in the molecule in the ethylenically unsaturated bond-containing component (1) is preferably 5 to 40% by mass relative to the total amount of the component (1). 7-25 mass% is more preferable, and 8-20 mass% is still more preferable.
In the present invention, the monomer means a monomer having a molecular weight of less than 1,000.
The molecular weight of the monomer is calculated from the atomic weight of the constituent atoms in the composition formula.
There is no restriction | limiting in particular as a monomer (B) which has an ethylenically unsaturated bond in a molecule | numerator, The monomer (b1) which has one ethylenically unsaturated group in a molecule | numerator, and two in a molecule | numerator The monomer (b2) which has the above ethylenically unsaturated group is mentioned.

(Transmittance of component containing ethylenically unsaturated bond (1))
The ethylenically unsaturated bond-containing component (1) preferably has a transmittance of 90% or more of the maximum absorption wavelength existing in the range of 370 to 420 nm of the photopolymerization initiator (2). If it is less than 90%, the light-shielding part cannot be cured well by light leaking from the irradiated light to the shadow part, narrow gap part or the like. From this viewpoint, the transmittance is more preferably 90% or more, and more preferably 95% or more. This transmittance | permeability can be suitably adjusted by changing the kind and content of each component in an ethylenically unsaturated bond containing component (1).
Here, the “transmittance” is a spectral transmittance value measured based on a method described in Japanese Industrial Standard Z8722.
Next, a method for adjusting the transmittance of the ethylenically unsaturated bond-containing component (1) will be described. A spacer having a thickness of 100 μm is arranged on the PET film, and after pouring the component (A), it is covered with the PET film, and after UV exposure, the PET film is peeled off to obtain a film having a thickness of 100 μm. Using this film as a sample, the transmittance in the range of 300 to 400 nm is measured with a spectrophotometer (manufactured by Hitachi, Ltd., U-3310 type).

(Content of ethylenically unsaturated bond-containing component (1))
Content of ethylenically unsaturated bond containing component (1) is 95-99.99 mass% with respect to the total amount of ethylenically unsaturated bond containing component (1) and photoinitiator (2). Is more preferable, it is more preferable that it is 97-99.99 mass%, and it is still more preferable that it is 98-99.9 mass%.

(Average number of functional groups of ethylenically unsaturated bond-containing component (1))
The average number of functional groups in the ethylenically unsaturated bond-containing component (1) (hereinafter sometimes referred to as the component (1)) is from the viewpoint of further reducing the viscosity and curing shrinkage of the liquid photocurable resin composition. It is preferably 5 to 2, more preferably 0.5 to 1.5, and still more preferably 0.5 to 1. “Number of functional groups” means the number of ethylenically unsaturated bonds in one molecule of component (1), and “average number of functional groups” means the number of ethylenically unsaturated bonds per molecule in the whole component (1). The average value is shown. The average number of functional groups can be calculated from the number of moles of each component when the component (1) is prepared. In addition, the average number of functional groups can be calculated from the integrated value of ¹ H-NMR of the component (1).

<Photopolymerization initiator (2)>
As a photoinitiator (2), what has a maximum absorption wavelength in the range of 370-420 nm is used. When the maximum absorption wavelength is out of the range of 370 to 420 nm, the light-shielding portion cannot be cured well by light scattered from the irradiated light to the shadow portion or narrow gap portion.
Specifically, as the photopolymerization initiator (2), bis (2,6-dimethoxybenzoyl) -2,4,4-trimethyl-pentylphosphine oxide (maximum absorption wavelength: 390 nm), 2,4,6 -Trimethylbenzoyl-diphenyl-phosphine oxide (maximum absorption wavelength: 380 nm), bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide (maximum absorption wavelength: 380 nm), and the like. You may use these by 1 type (s) or 2 or more types.

An initiator having a maximum absorption wavelength of less than 370 nm may be used in combination with the photopolymerization initiator (2). By using together, it has the effect that hardening of an exposed part fully advances.
Specifically, 1-hydroxy-cyclohexyl phenyl ketone (maximum absorption wavelength: 330 nm), 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one (Maximum absorption wavelength: 340 nm), 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) ) -Butanone-1 (maximum absorption wavelength: 320 nm), 2-dimethylamino-2- (4-methyl-benzyl) -1- (4-morpholin-4-yl-phenyl) -butan-1-one (maximum absorption) Wavelength: 330 nm), 2-hydroxy-2-methyl-1-phenylpropan-1-one (maximum absorption wavelength: 330 nm), 2,2-dimethoxy-1,2 Diphenylethane-1-one (maximum absorption wavelength: 340 nm), ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl]-, 1- (0-acetyloxime) Oxy-phenyl-acetic acid 2- [2-oxo-2-phenyl-acetoxy-ethoxy] -ethyl ester and oxy-phenyl-acetic acid 2- [2-hydroxy-ethoxy] -ethyl ester (Maximum absorption wavelength: 330 nm), phenylglyoxylic acid methyl ester (maximum absorption wavelength: 340 nm), and the like. These may be used alone or in combination of two or more.

  In this invention, 0.01-5 mass% is preferable with respect to 100 mass parts of (1) component, as for content of a photoinitiator (2), 0.05-3 mass% is more preferable, 0.1-0.1 mass%. 2% by mass is particularly preferred. When content exceeds 5 mass%, it will become a factor of coloring of hardened | cured material. Moreover, if it is less than 0.01% by mass, the light shielding part is not sufficiently cured.

<Phosphor (3)>
It is preferable that the liquid photocurable resin composition of the present invention further contains a phosphor (3). As the phosphor (3), it is preferable that the excitation wavelength is 300 to 400 nm and the fluorescence wavelength is 350 to 450 nm.
The reason is estimated as follows. That is, since the photopolymerization initiator (2) used in the present invention has a maximum absorption wavelength in the range of 370 to 420 nm, the wavelength in the range of 300 to 400 nm cannot be sufficiently absorbed. On the other hand, the phosphor (C) absorbs ultraviolet light used for such a photocuring reaction and emits fluorescence having a wavelength (350 to 450 nm) close to the maximum absorption wavelength. The existing photopolymerization initiator (B) absorbs well. Thereby, it is considered that the polymerization initiating action of the photopolymerization initiator (2) is sufficiently expressed and the light shielding part is sufficiently cured.

Specific examples of the phosphor (3) include pyrene, benzopyrene, perylene, anthracene, dimethylanthracene, naphthalene, naphthalenecarboxylic acid, phenanthrene, and coumarin. Among these, pyrene, benzopyrene, perylene, anthracene, naphthalene, phenanthrene, and coumarin without yellow coloring are preferable. Among the coumarins, hydroxymethylcoumarins such as 7-hydroxy-4-methylcoumarin and 4-hydroxy-7-methylcoumarin are preferable from the viewpoint of improving transparency.
The content in the case of using the phosphor (3) is preferably 0.001 to 2% by mass with respect to 100 parts by mass of the component (1) from the viewpoint of improving the curability and transparency of the light-shielding part. 005 to 1 mass% is more preferable, and 0.01 to 0.5 mass% is still more preferable.

<(4) Component: Thiol compound>
The liquid photocurable resin composition of the present invention preferably further contains a thiol compound (4). The component (4) used in the present invention is preferably a secondary thiol compound represented by the following general formula (7).

(In General Formula (7), A represents a p-valent organic group, and p represents an integer of 1 to 6.)
Examples of such compounds include 1,4-bis (3-mercaptobutyryloxy) butane, 1,3,5-tris (3-mercaptobutyryloxyethyl) -1,3,5-triazine-2. , 4, 6 (1H, 3H, 5H) -trione, pentaerythritol tetrakis (3-mercaptobutyrate), and the like. These compounds are available from Showa Denko KK as Karenz MT series (Karenz MT BD1, Karenz MT NR1, Karenz MT PE1, etc.). These compounds can be used individually by 1 type or in combination of 2 or more types.
The content of the thiol compound represented by the general formula (7) which is the component (4) used in the present invention is based on the total amount of all components in the resin composition from the viewpoint of the curability of the light shielding part and the wet heat resistance. 1 to 30% by mass is preferable, 2 to 20% by mass is more preferable, and 3 to 10% by mass is still more preferable.

<Other ingredients>
The liquid photocurable resin composition of the present invention may contain various additives as necessary, for example, an adhesion improver such as a silane coupling agent, a hindered amine light stabilizer, a phenolic Phosphorous antioxidants, curing accelerators, chain transfer agents such as thiol compounds, dyes, fillers, pigments, thixotropic agents, plasticizers, flame retardants, mold release agents, surfactants, lubricants, antistatic agents, Additives such as various fillers and heavy metal deactivators can be added. These may be used alone or in combination of two or more.

The curing shrinkage when the liquid photocurable resin composition of the present invention is cured is preferably less than 1.4% from the viewpoint of further highly suppressing the warpage of a substrate such as a protective panel or an image display unit. Preferably it is less than 1.0%. If the curing shrinkage is less than 1.4%, the warp that may occur in the image display unit can be sufficiently suppressed, and the occurrence of defects such as color unevenness when used in an image display device can be prevented. it can.
The light transmittance at a wavelength of 400 nm at a film thickness of 175 μm of the cured product of the liquid photocurable resin composition of the present invention is preferably 90% or more, more preferably 95% or more, and still more preferably 98% or more.
The dielectric constant at 100 kHz of the cured product of the liquid photocurable resin composition of the present invention is preferably 5 or less, more preferably 4 or less, and still more preferably 3 or less. The lower limit value of the dielectric constant is preferably 1 or more, more preferably 1.5 or more, and still more preferably 2 or more.
Moreover, in the liquid photocurable resin composition of this invention, it is preferable that an organic solvent (solvent) is not included substantially from a viewpoint of heat-and-moisture resistance reliability and suppressing the bubble generation in hardened | cured material. “Substantially” means that the liquid photocurable resin composition of the present invention does not significantly deteriorate the characteristics after photocuring, and the organic solvent is in a trace amount (1% by mass or less) in the liquid photocurable resin composition. Is preferably present, but preferably not contained.
When the liquid photocurable resin composition does not substantially contain an organic solvent, the viscosity (25 ° C.) of the liquid photocurable resin composition is preferably 10 to 50,000 mPa · s, preferably 100 to 10, 000 mPa · s is more preferable, and 500 to 5,000 mPa · s is even more preferable. The viscosity is a value measured at 0.5 revolutions / minute using an E-type viscometer (RE-80L manufactured by Toki Sangyo Co., Ltd.) using a 3 ° cone rotor.

[Optical member]
The liquid photocurable resin composition of the present invention can be applied to an optical member. The optical member is formed by curing the liquid photocurable resin composition described above by light irradiation.
Examples of the optical member include optical films, optical sheets, transparent substrates, lenses, adhesives, optical waveguides, solar cell members, light-emitting diodes (LEDs), phototransistors, photodiodes, and solid-state imaging devices. , Lighting devices, image display devices, and the like. In particular, it is suitable for use in an image display device.

[Image display device]
The image display device of the present invention includes an image display unit having an image display unit, a protective panel having a light-shielding unit along an outer peripheral edge, and a laminate including a resin layer existing between the image display unit and the protective panel. In the image display device having a structure, the resin layer is a cured product of the liquid photocurable resin composition.
The image display device of the present invention includes an image display unit having an image display unit, a touch panel, a protective panel having a light-shielding part along the outer periphery, and a resin layer present between the touch panel and the protective panel. An image display device having a laminated structure including the resin layer, wherein the resin layer is a cured product of the liquid photocurable resin composition.
In this method of manufacturing an image display device, an image display unit or touch panel having an image display unit and a protective panel having a light-shielding unit along the outer peripheral edge are arranged to face each other, and a liquid photocurable resin composition is interposed between the gaps. A liquid photocurable resin composition for curing the liquid photocurable resin composition, wherein the liquid photocurable resin composition is interposed and cured by light irradiation from at least the protective panel surface side. Is.
Next, a liquid crystal display device which is an example of an image display device will be described.

<Liquid crystal display device>
FIG. 1 is a side sectional view schematically showing an embodiment of a liquid crystal display device. The liquid crystal display device shown in FIG. 1 includes an image display unit 1 in which a backlight system 50, a polarizing plate 22, a liquid crystal display cell 10, and a polarizing plate 20 are laminated in this order, and a polarizing plate on the viewing side of the liquid crystal display device. 20 includes a resin layer 32 provided on the upper surface of 20 and a transparent protective substrate (protective panel) 40 provided on the surface thereof. The resin layer 32 is comprised from the hardening body of the liquid photocurable resin composition of this embodiment.

FIG. 2 is a side cross-sectional view schematically showing a liquid crystal display device equipped with a touch panel, which is an embodiment of the liquid crystal display device. The liquid crystal display device shown in FIG. 2 includes an image display unit 1 in which a backlight system 50, a polarizing plate 22, a liquid crystal display cell 10, and a polarizing plate 20 are laminated in this order, and a polarizing plate on the viewing side of the liquid crystal display device. 20 from the resin layer 32 provided on the upper surface, the touch panel 30 provided on the upper surface of the resin layer 32, the resin layer 31 provided on the upper surface of the touch panel 30, and the transparent protective substrate 40 provided on the surface thereof. Composed. The resin layers 31 and 32 are composed of a cured body of the liquid photocurable resin composition of the present embodiment.
In the liquid crystal display device of FIG. 2, resin layers are interposed between the image display unit 1 and the touch panel 30 and between the touch panel 30 and the transparent protective substrate 40. It suffices to intervene in at least one. When the touch panel is on-cell, the touch panel and the liquid crystal display cell are integrated. As a specific example, the liquid crystal display cell 10 of the liquid crystal display device of FIG. 1 may be replaced with an on-cell.
In FIG. 2, when using a protective panel having a light-shielding portion along the outer peripheral edge, it is particularly preferable that at least the resin layer 31 uses the liquid photocurable resin composition of the present invention.
The light transmittance of the resin layer 31 or 32 is preferably 90% or more, and more preferably 95% or more with respect to light having a wavelength of 400 nm.

  According to the liquid crystal display device shown in FIGS. 1 and 2, since the cured body of the liquid photocurable resin composition of the present embodiment is provided as the resin layer 31 or 32, it has impact resistance and is not sharp and has no double image. A high contrast image can be obtained.

The liquid crystal display cell 10 can be made of a liquid crystal material well known in the art. Further, depending on the control method of the liquid crystal material, it is classified into TN (Twisted Nematic) method, STN (Super-twisted nematic) method, VA (Virtual Alignment) method, IPS (In-Place-Switching) method, etc. It may be a liquid crystal display cell using a control method.
As the polarizing plates 20 and 22, a polarizing plate common in this technical field can be used. The surfaces of these polarizing plates may be subjected to treatments such as antireflection, antifouling, and hard coat. Such surface treatment may be performed on one side of the polarizing plate or on both sides thereof.
As the touch panel 30, what is generally used in this technical field can be used.
The resin layer 31 or 32 can be formed with a thickness of 0.02 mm to 3 mm, for example. In particular, the liquid photocurable resin composition of the present embodiment is effective for thick films, and can be suitably used when the resin layer 31 or 32 having a thickness of 0.1 mm or more is formed.
As the transparent protective substrate 40, a general optical transparent substrate can be used. Specific examples thereof include inorganic plates such as glass plates and quartz plates, resin plates such as acrylic resin plates and polycarbonate plates, and resin sheets such as thick polyester sheets. When high surface hardness is required, a plate such as glass or acrylic resin is preferable, and a glass plate is more preferable. The surface of these transparent protective substrates may be subjected to treatments such as antireflection, antifouling, and hard coating. Such surface treatment may be performed on one side of the transparent protective substrate or on both sides. A plurality of transparent protective substrates can be used in combination.
The backlight system 50 typically includes a reflecting unit such as a reflecting plate and an illuminating unit such as a lamp.

1 includes the step of interposing the liquid photocurable resin composition of the present embodiment between the image display unit 1 and the transparent protective substrate (protective panel) 40, and the surface of the protective panel 40. The liquid photocurable resin composition is cured by irradiating light from the side, and the resin layer 32 is formed.
As a method of interposing the liquid photocurable resin composition between the image display unit 1 and the protection panel 40, for example, a liquid photocurable resin composition is used on the image display unit 1 or the protection panel 40 by using a dispenser. A method in which the liquid photocurable resin composition is cast between the image display unit 1 and the protective panel 40 that are arranged with a certain interval between them. Is mentioned. When casting the liquid photocurable resin composition, a dam (a frame for preventing the liquid photocurable resin composition from flowing out) is formed around the image display unit 1 and the protection panel 40. May be.

  The liquid crystal display device of FIG. 2 described above includes the liquid photocurable resin composition of the present embodiment between the image display unit 1 and the touch panel 30 and / or between the touch panel 30 and the protective panel 40. And a process of forming the resin layers 32 and 31 by irradiating light from the surface side of the protective panel 40 to cure the liquid photocurable resin composition. . Examples of the method of interposing the liquid photocurable resin composition include the same method as in the case of the liquid crystal display device shown in FIG.

The light irradiation, for example, using an ultraviolet irradiation device can be carried out under the conditions of exposure ^{500mJ / cm 2 ~5000mJ / cm 2} . The exposure amount refers to a value obtained by multiplying the illuminance that can be measured with an ultraviolet illuminance meter UV-M02 (receiver: UV-36) manufactured by Oak Co., Ltd. by the irradiation time (seconds). The light source for ultraviolet irradiation may be a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, a metal halide lamp, an LED lamp or the like, but it is preferable to use a high pressure mercury lamp or a metal halide lamp.
In addition, in the case of light irradiation, you may use together irradiation from the protective panel 40 surface side, and irradiation from a side surface.
Moreover, hardening can also be accelerated | stimulated by heating the laminated body containing a liquid photocurable resin composition simultaneously with light irradiation.

  The liquid crystal display device that can be manufactured by using the liquid photocurable resin composition of the present embodiment has been described above. However, it can be manufactured by using the liquid photocurable resin composition of the present embodiment. The possible image display device is not limited to this, and can be applied to a plasma display (PDP), a cathode ray tube (CRT), a field emission display (FED), an organic EL display, a 3D display, an electronic paper, and the like.

EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the scope of the present invention is not limited thereto.
<Raw materials>
In addition, as a raw material etc., the following were used.
(1) Ethylenically unsaturated bond-containing component (polymer (A) having a (meth) acryloyl group in the side chain)
The acrylic polymer 1 was synthesized as follows.
9.9 g of lauryl acrylate (manufactured by Kyoeisha Chemical Co., Ltd.), 0.1 g of hydroxybutyl acrylate (manufactured by Nippon Kasei Co., Ltd.), 0.075 g of n-octyl mercaptan (manufactured by Wako Pure Chemical Industries, Ltd.) and perbutyl O ( (Nissho Co., Ltd.) 0.05 g was added, and after stirring, placed in an 80 ° C. water bath and heated for 4 hours. Subsequently, after hold | maintaining in 100 degreeC oven for 1 hour, it removed from oven and left until it became room temperature (about 25 degreeC). Next, 0.0051 g of methyl ether hydroquinone (manufactured by Wako Pure Chemical Industries, Ltd.) and 0.108 g of 2-methacryloyloxyethyl acrylate (manufactured by Showa Denko KK) were added. The screw tube was heated in a bath at 60 ° C. for 3 hours to obtain the target acrylic polymer 1 (weight average molecular weight of about 10,000).
The acrylic polymer 2 was synthesized in the same manner as the acrylic polymer 1 except that lauryl acrylate was changed to 2-ethylhexyl acrylate (manufactured by Kyoeisha Chemical Co., Ltd.).
Acrylic polymer 3 contains 10 g of lauryl acrylate (manufactured by Kyoeisha Chemical Co., Ltd.), 0.075 g of n-octyl mercaptan (manufactured by Wako Pure Chemical Industries, Ltd.) and 0.05 g of perbutyl O (manufactured by NOF Corporation) in a screw tube. After stirring, the mixture was placed in an 80 ° C. water bath and heated for 4 hours. Next, after being kept in an oven at 100 ° C. for 1 hour, it was removed from the oven and allowed to reach room temperature to obtain an acrylic polymer 3 as a target product.
UC-102: an isoprene having a methacryloyl group ((manufactured by Kuraray Co., Ltd., having the structure shown in the general formula (6), n = 2, number average molecular weight 17,000)

（（Ａ）成分以外の（メタ）アクリロイル基を有する化合物（Ｂ））
ライトアクリレートＬＡ（商品名）：ラウリルアクリレート（共栄社化学株式会社製）
ＤＣＰ−Ａ（商品名）：ジシクロペンタジエンジメタノールジアクリレート（共栄社化学株式会社製）

(Compound (B) having a (meth) acryloyl group other than the component (A))
Light acrylate LA (trade name): Lauryl acrylate (manufactured by Kyoeisha Chemical Co., Ltd.)
DCP-A (trade name): dicyclopentadiene dimethanol diacrylate (manufactured by Kyoeisha Chemical Co., Ltd.)

(2) Photopolymerization initiator The following photopolymerization initiators are all manufactured by BASF. In addition, the maximum absorption wavelength of each polymerization initiator is a value described in the catalog.
Darocur-TPO; 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide (maximum absorption wavelength 380 nm) (hereinafter sometimes referred to as D-TPO)
Irgacure-1870; a mixture of bis (2,6-dimethoxybenzoyl) -2,4,4-trimethyl-pentylphosphine oxide (maximum absorption wavelength 390 nm) and i-184 (maximum absorption wavelength 330 nm) (hereinafter i-1870) Sometimes called)
Irgacure-184 (trade name); 1-hydroxy-cyclohexyl-phenyl-ketone (maximum absorption wavelength 330 nm) (hereinafter sometimes referred to as i-184)

(3) Phosphor 7-hydroxy-4-methylcoumarin: (Wako Pure Chemical Industries, Ltd., excitation wavelength: 320 nm, fluorescence wavelength: 380 nm)
(4) Thiol compound Karenz MT PE1 (trade name): pentaerythritol tetrakis (3-mercaptobutyrate) (manufactured by Showa Denko KK)

<Example 1>
Acrylic polymer 1 (100 g) as component (A) and D-TPO (0.5 g) as photopolymerization initiator (2) are added to the screw tube and stirred with a revolving mixer to obtain a liquid photocurable resin composition. Obtained.

<Examples 2 to 10>
In Examples 2-10, the liquid photocurable resin composition was obtained by the same method as Example 1 except having changed and prepared as shown in Table 1.

<Comparative Examples 1-5>
In Comparative Examples 1 to 5, a liquid photocurable resin composition was obtained in the same manner as in Example 1 except that the amount was changed as shown in Table 2.

<Evaluation>
(Evaluation of transmittance)
A liquid photo-curable resin composition is dropped onto a PET film, and another PET film is bonded so as to have a film thickness of 175 μm, and ultraviolet light is irradiated at 1,000 mJ / cm ² using an ultraviolet irradiation device to produce liquid light. A transparent sheet in which the curable resin composition was cured was produced. The transmittance of the transparent sheet was measured using a spectrophotometer (U-3310 manufactured by Hitachi, Ltd.). The transmittance was evaluated when the transmittance was 400 nm.

(Evaluation of dielectric constant)
A release PET film (Iupilon A63 manufactured by Teijin DuPont Co., Ltd.) and a circular frame made of silicon rubber (thickness 2 mm, inner diameter 56 mm) were placed on a glass plate, and a liquid photocurable resin composition was poured into the glass plate. Further, a release PET film was placed on the frame, and UV irradiation was performed on each side (irradiation amount on one side: 1 J / cm ² ) to obtain a molded body. After measuring the thickness (d) of this molded body using a micrometer, it was attached to an aluminum plate (thickness 2 mm) having a diameter of 56 mm, a copper foil having a diameter of 36 mm, an outer diameter of 54 mm, and an inner diameter on the other surface. A 40 mm ring-shaped copper foil was attached to obtain a measurement sample. The measurement sample was measured for capacitance (C) at a frequency of 100 kHz using HP4275A and HP16451B manufactured by Hewlett-Packard Company, and the dielectric constant εr was determined by substituting it into the following equation. Here, ε ₀ is the dielectric constant of vacuum.
C = ε ₀ x εr x (π x 18 mm x 18 mm) ÷ d

(Evaluation of curing of shadow area)
The curability of the liquid photocurable resin compositions obtained in the above examples and comparative examples was evaluated by the following method. That is, a spacer having a thickness of 100 μm with a 3 cm × 3 cm hole is laid on a 10 × 10 cm glass, and after filling the liquid photocurable resin composition in the hole, the 10 cm × 10 cm glass is used from above. Covered. Next, half of the 3 cm × 3 cm hole portion was covered with a black cloth, half of the resin portion was used as a shadow portion, and the other half was used as a light irradiation portion. Next, photocuring was performed with an energy amount of 1000 mJ / cm ² using an exposure machine (High Power Metal Halide Lamp, manufactured by Eye Graphics Co., Ltd.). Thereafter, the black cloth and the cover glass were removed, and the cured sample was taken out. The length (mm) which hardened | cured to the shadow part side rather than the boundary of a shadow part and a light irradiation part among samples was measured.

(Evaluation of cure shrinkage)
The resin composition was dropped onto the PET film, and another PET film was bonded so as to have a film thickness of 175 μm, and the resin composition was cured by irradiating ultraviolet rays at 1,000 mJ / cm ² using an ultraviolet irradiation device. A transparent sheet was prepared. The specific gravity of this transparent sheet and the resin composition before curing was measured using an electronic hydrometer (Alpha Mirage SD-200L), and the curing shrinkage was calculated from the following equation.
Curing shrinkage (%) = {(specific gravity of the resin composition after curing−specific gravity of the resin composition before curing) / specific gravity of the resin composition after curing} × 100

＊表中の数値単位は全て質量部とする。

* All numerical units in the table are parts by mass.

＊表中の数値単位は全て質量部とする。
＊１：硬化しなかったため未評価

* All numerical units in the table are parts by mass.
* 1: Not evaluated because it did not cure

  Comparative Examples 1 to 5 using a photopolymerization initiator having a maximum absorption wavelength not in the range of 370 to 420 nm are cured as in Comparative Example 1 in which a polymer (A) having a (meth) acryloyl group in the side chain is not used. It was not, or the transmittance | permeability was bad like the comparative example 2, or the part which a light does not hit directly like the comparative examples 3-5 did not harden | cure. On the other hand, Example 1 using an ethylenically unsaturated bond-containing component containing a photopolymerization initiator having a maximum absorption wavelength in the range of 370 to 420 nm and a polymer (A) having a (meth) acryloyl group in the side chain. 10 to 10 can cure a portion that is not directly exposed to light, has an appropriate dielectric constant, and is excellent in light transmittance. In particular, the inclusion of the thiol compound (4) was effective.

DESCRIPTION OF SYMBOLS 1 Image display unit 10 Liquid crystal display cell 20,22 Polarizing plate 30 Touch panel 31,32 Resin layer 40 Transparent protective substrate (protection panel)
50 Backlight system

Claims (12)

A liquid photocurable resin composition comprising an ethylenically unsaturated bond-containing component (1) containing a polymer (A) having a (meth) acryloyl group in the side chain, and a photopolymerization initiator (2),
A liquid photocurable resin composition in which the photopolymerization initiator (2) has a maximum absorption wavelength in a range of 370 to 420 nm.   Furthermore, the liquid photocurable resin composition of Claim 1 containing fluorescent substance (3).   The liquid photocurable resin composition according to claim 2, wherein the phosphor (3) is at least one selected from the group consisting of pyrene, benzopyrene, perylene, anthracene, naphthalene, phenanthrene, and coumarin.   Furthermore, the liquid photocurable resin composition of any one of Claims 1-3 containing a thiol compound (4).   The liquid photocurable resin composition according to any one of claims 1 to 4, wherein the polymer (A) having a (meth) acryloyl group in a side chain is an acrylic polymer having a (meth) acryloyl group.   A gap between an image display unit having an image display unit and a protective panel having a light shielding portion along the outer peripheral edge or a gap between a touch panel and a protective panel having a light shielding portion along the outer peripheral edge is used for filling a gap. The liquid photocurable resin composition according to any one of the above.   The image display apparatus which has a layer formed from the liquid photocurable resin composition of any one of Claims 1-5 in the visual recognition side.   The layer formed from the liquid photocurable resin composition according to any one of claims 1 to 5, wherein the layer is between the viewing-side protection plate and the image display panel, between the viewing-side protection plate and the touch panel, and the touch panel. The image display device according to claim 7, wherein the image display device is formed between the image display panel and the image display panel.   A sheet obtained by curing the liquid photocurable resin composition according to any one of claims 1 to 5 into a sheet shape, and a layer containing any of polymethyl methacrylate, polyethylene terephthalate, polycarbonate, and a polarizing plate; An image display device characterized by being in contact.   An image display device having a laminated structure including an image display unit having an image display unit, a protective panel having a light-shielding unit along an outer periphery, and a resin layer existing between the image display unit and the protective panel. And the said resin layer is an image display apparatus which is a hardened | cured material of the liquid photocurable resin composition of any one of Claims 1-6.   An image display device having a laminated structure including an image display unit having an image display unit, a touch panel, a protective panel having a light shielding portion along an outer peripheral edge, and a resin layer existing between the touch panel and the protective panel. And the said resin layer is an image display apparatus which is a hardened | cured material of the liquid photocurable resin composition of any one of Claims 1-6.   An image display unit or touch panel having an image display unit and a protective panel having a light-shielding unit along the outer peripheral edge are arranged to face each other, and the liquid photocurable resin composition is interposed between the liquid photocurable resin compositions in the gaps. A method of manufacturing an image display device for curing an object, wherein the liquid photocurable resin composition according to any one of claims 1 to 6 is interposed in the gap, and light is irradiated at least from the protective panel surface side. The manufacturing method of the image display apparatus which hardens by performing.

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