JP5935337B2 - Liquid photocurable resin composition, optical member, image display device and method for producing the same - Google Patents

Description

  The present invention is 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 the curing. Related to things. The present invention also provides an optical film, a transparent substrate, a lens, an adhesive, an adhesive, a filler, an optical waveguide, a solar cell member, a light emitting diode (LED) using the cured product of the liquid photocurable resin composition. ), An optical member such as a phototransistor, a photodiode, a solid-state imaging device, an optical display device, an image display device, an illumination device, etc., and an image display device among these optical members, and a manufacturing method thereof.

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.

  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 liquid photocurable resin composition capable of curing a non-contact portion and capable of obtaining a highly transparent cured product by the curing. Another object of the present invention is to provide an optical member, an image display device, and a manufacturing method thereof using the liquid photocurable resin composition.

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 When the agent has a maximum absorption wavelength in the range of 370 to 420 nm, and the transmittance of the ethylenically unsaturated bond-containing component (1) at the maximum absorption wavelength is 90% or more, a shadow portion or a narrow gap portion Etc. (sometimes referred to as “light-shielding part”) were found to be cured well.
The present invention has been completed based on such findings.

That is, the present invention relates to the following [1] to [10].
[1] An ethylenically unsaturated bond-containing component (1) containing a polymer (A) having an ethylenically unsaturated group in the molecule and a monomer (B) having an ethylenically unsaturated group in the molecule, and light A liquid photocurable resin composition comprising a polymerization initiator (2), wherein the photopolymerization initiator (2) has a maximum absorption wavelength in the range of 370 to 420 nm, and ethylene at the maximum absorption wavelength Liquid photocurable resin composition in which the transmittance of the polymerizable unsaturated bond-containing component (1) is 88% or more.
[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) has an excitation wavelength in the range of 300 to 400 nm and a fluorescence wavelength in the range of 350 to 450 nm.
[4] The liquid photocurable material according to [2] or [3], wherein the phosphor (3) is at least one selected from the group consisting of pyrene, benzopyrene, perylene, anthracene, naphthalene, phenanthrene, and coumarin. Resin composition.
[5] Any of [2] to [4], wherein the content of the phosphor (3) is 0.001 to 2 parts by mass with respect to 100 parts by mass of the ethylenically unsaturated bond-containing component (1). The liquid photocurable resin composition described in 1.
[6] The liquid photocurable resin according to any one of [1] to [5], wherein the polymer (A) having an ethylenically unsaturated bond in the molecule is a urethane polymer having a (meth) acryloyl group. Composition.
[7] The content of the polymer (A) having an ethylenically unsaturated bond in the molecule in the ethylenically unsaturated bond-containing component (1) is 60 to 95% by mass of [1] to [6] The liquid photocurable resin composition according to any one of the above.
[8]
[1] to [1] 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 touch panel and a protective panel having a light shielding portion along the outer peripheral edge. 7] The liquid photocurable resin composition according to any one of [7].
[9] An optical member obtained by curing the liquid photocurable resin composition according to any one of [1] to [8] by light irradiation.
[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. An image display device, wherein the resin layer is a cured product of the liquid photocurable resin composition according to any one of [1] to [8].
[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. An image display device, wherein the resin layer is a cured product of the liquid photocurable resin composition according to any one of [1] to [8].
[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 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 [1] to [8] is interposed in the gap, and light is transmitted at least from the protective panel surface side. A method for manufacturing an image display device that is cured by irradiation.

  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 high transparency by the curing, an optical member using the liquid photocurable resin composition, an image display device, 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 polymer (A) having an ethylenically unsaturated group in the molecule and a monomer (B) having an ethylenically unsaturated group in the molecule. A liquid photocurable resin composition comprising a bond-containing component (1) and a photopolymerization initiator (2), wherein the photopolymerization initiator (2) has a maximum absorption wavelength in the range of 370 to 420 nm. The transmittance of the ethylenically unsaturated bond-containing component (1) at the maximum absorption wavelength is 88% or more.
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) includes a polymer (A) having an ethylenically unsaturated bond in the molecule and a monomer (B) having an ethylenically unsaturated group in the molecule. Moreover, this ethylenically unsaturated bond containing component (1) has the transmittance | permeability of the ethylenically unsaturated bond containing component (1) in the maximum absorption wavelength which exists in the range of 370-420 nm of a photoinitiator (2). It is 88% or more.
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 having ethylenically unsaturated bond in molecule (A))
Examples of the polymer (A) having an ethylenically unsaturated bond in the molecule include a polyester oligomer having a (meth) acryloyl group, a urethane polymer having a (meth) acryloyl group, and an acrylic acrylate having a (meth) acryloyl group. A polymer etc. are mentioned.
Among these, in particular, flexibility is imparted to the liquid photocurable resin composition, it becomes easy to bond the image display unit and the protection panel, and from the viewpoint of the toughness of the cured product and the balance of various properties, A urethane polymer having a (meth) acryloyl group is preferred.
In the present invention, the polymer means a polymer having a weight average molecular weight of 1,000 or more.

[Method for producing urethane polymer having (meth) acryloyl group]
The urethane polymer having a (meth) acryloyl group is, for example, a compound obtained by reacting (i) a diol compound and (ii) a compound having an isocyanate group (hereinafter sometimes referred to as a urethane oligomer). , (Iii) monohydroxy (meth) acrylate, (iv) monocarboxylic acid having (meth) acryloyl group, or (v) monoisocyanate compound having (meth) acryloyl group.

≪ (i) Diol compound≫
(I) Examples of the diol compound include polyolefin diols such as polyethylene glycol, polypropylene glycol, polybutadiene diol, polyisoprene diol, hydrogenated polybutadiene diol, hydrogenated polyisoprene diol, polyether diol, polyester diol, polycaprolactone diol, and silicone. Diol etc. are mentioned. Among these, polyolefin diol is particularly preferable from the viewpoints of curability and adhesion.

<< (ii) Compound having an isocyanate group >>
(Ii) As a compound which has an isocyanate group, the diisocyanate compound represented by the following general formula (I) is mentioned, for example.
OCN-X-NCO (I)
[In the formula (I), X represents a divalent organic group. ]
Examples of the divalent organic group represented by X in the general formula (I) include, for example, an alkylene group having 1 to 20 carbon atoms, an unsubstituted group, or a lower alkyl group having 1 to 5 carbon atoms such as a methyl group. And arylene groups such as a phenylene group and a naphthylene group. The number of carbon atoms of the alkylene group is more preferably 1-18. The divalent organic group represented by X has an aromatic ring such as a phenylene group, a xylylene group, a naphthylene group, a diphenylmethane-4,4′-diyl group, a diphenylsulfone-4,4′-diyl group. Groups. Also included are hydrogenated diphenylmethane-4,4′-diyl groups.

  Examples of the diisocyanates represented by the general formula (I) include diphenylmethane-2,4′-diisocyanate; 3,2′-, 3,3′-, 4,2′-, 4,3 ′. -, 5,2'-, 5,3'-, 6,2'- or 6,3'-dimethyldiphenylmethane-2,4'-diisocyanate; 3,2'-, 3,3'-, 4,2 '-, 4,3'-, 5,2'-, 5,3'-, 6,2'- or 6,3'-diethyldiphenylmethane-2,4'-diisocyanate; 3,2'-, 3, 3'-, 4,2'-, 4,3'-, 5,2'-, 5,3'-, 6,2'- or 6,3'-dimethoxydiphenylmethane-2,4'-diisocyanate; diphenylmethane -4,4'-diisocyanate; diphenylmethane-3,3'-diisocyanate; diphenylmethane-3,4'-diisocyanate Phenylmethane diisocyanate compounds and hydrogenated products thereof; diphenyl ether-4,4′-diisocyanate; benzophenone-4,4′-diisocyanate; diphenylsulfone-4,4′-diisocyanate; tolylene-2,4-diisocyanate, tolylene-2 M-xylylene diisocyanate; p-xylylene diisocyanate; 1,5-naphthalene diisocyanate; 4,4 ′-[2,2-bis (4-phenoxyphenyl) propane] diisocyanate; Hexamethylene diisocyanate; 2,2,4-trimethylhexamethylene diisocyanate; isophorone diisocyanate; 4,4'-dicyclohexylmethane diisocyanate; transcyclohexane-1,4-di Isocyanate; hydrogenated m- xylylene diisocyanate, aliphatic or alicyclic isocyanates such lysine diisocyanate. Among these diisocyanates, it is preferable to use an aliphatic diisocyanate compound in which X in the formula (I) is a group having an aliphatic group. These can be used alone or in combination of two or more. In addition, as a compound which has an isocyanate group, you may use trifunctional or more polyisocyanate with the diisocyanate represented by general formula (I).

  The diisocyanates represented by the above general formula (I) may be stabilized with a blocking agent necessary to avoid changes over time. Examples of the blocking agent include hydroxy acrylate, alcohol typified by methanol, phenol, oxime and the like, but there is no particular limitation.

<< (i) Mixing ratio of diol compound and diisocyanate represented by general formula (I) >>
The blending ratio when the (i) diol compound and the diisocyanate represented by the general formula (I) are reacted is the number average molecular weight of the urethane oligomer to be produced and the terminal of the urethane oligomer to be produced is a hydroxyl group. Or an isocyanate group.

  When the end of the urethane oligomer is an isocyanate group, the ratio of the number of isocyanate groups to the number of hydroxyl groups (number of isocyanate groups / number of hydroxyl groups) is preferably adjusted to be 1.01 or more, from the viewpoint of increasing the number average molecular weight. Is preferably adjusted to less than 2. By setting such a ratio, a urethane oligomer having an isocyanate group at the end can be obtained. Examples of the compound for introducing the (meth) acryloyl skeleton include (iii) monohydroxy (meth) acrylate compounds described later.

On the other hand, when the terminal of the urethane oligomer is a hydroxyl group, it is preferable to adjust the blending ratio so that the ratio between the number of hydroxyl groups and the number of isocyanate groups (number of hydroxyl groups / isocyanate groups) is 1.01 or more. From the viewpoint of increasing, it is preferable to adjust to less than 2.
When the terminal of the urethane oligomer is a hydroxyl group, a compound capable of reacting with a hydroxyl group, such as (iv) monocarboxylic acids having a (meth) acryloyl group, (v) a monoisocyanate compound having a (meth) acryloyl group, and urethane By reacting with the terminal hydroxyl group of the oligomer, a urethane oligomer having two (meth) acryloyl groups can be obtained.

≪ (iii) Monohydroxy (meth) acrylate≫
Examples of the (iii) monohydroxy (meth) acrylate include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and 1,4-cyclohexanedimethanol mono (Meth) acrylate, caprolactone or alkylene oxide adduct of each of the above (meth) acrylates, glycerin di (meth) acrylate, trimethylolpropane di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) Examples include acrylate, ditrimethylolpropane tri (meth) acrylate, and 2-acryloxyethanol. These monohydroxy compounds can be used alone or in combination of two or more.

<< (iv) Monocarboxylic acids having a (meth) acryloyl group; (v) Monoisocyanate compounds having a (meth) acryloyl group >>
(Iv) Monocarboxylic acids having a (meth) acryloyl group include (meth) acrylic acid and the like, and (v) monoisocyanate compounds having a (meth) acryloyl group include 2-isocyanatoethyl (meth) acrylate and the like. Can be mentioned.

[Other methods for producing a urethane polymer having a (meth) acryloyl group]
Moreover, the urethane polymer which has a (meth) acryloyl group can also be manufactured by methods other than the above.
As other methods for producing a urethane polymer having a (meth) acryloyl group, for example, (i) a diol compound and (iii) a monohydroxy (meth) acrylate are mixed in a predetermined amount, and the temperature is raised to a predetermined temperature. Thereafter, (ii) a predetermined amount of the compound having an isocyanate group is added to the mixture of the component (i) and the component (iii) over a predetermined period of time and reacted.
The urethane polymer having a (meth) acryloyl group is prepared by using the above-described components in the presence of the above-described components in the presence of a conventionally known method, for example, a polymerization inhibitor such as p-methoxyphenol and a catalyst such as dibutyltin dilaurate. It can manufacture by the method of reacting.

[Weight average molecular weight of polymer (A) having an ethylenically unsaturated bond in the molecule]
The weight average molecular weight of the polymer (A) having an ethylenically unsaturated bond in the molecule may be 1,000 to 50,000 from the viewpoints of curability, flexibility, workability, and wet heat resistance. Preferably, it is 2,000 to 40,000, more preferably 3,000 to 30,000.
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), molecules with molecular weight M _i is the N _i number exists, is defined as follows.
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 an ethylenically unsaturated bond in the molecule]
The content of the polymer (A) having an ethylenically unsaturated bond in the molecule is preferably 60 to 95% by mass, and 75 to 93% by mass with respect to the total amount of the ethylenically unsaturated bond-containing component (1). More preferably, 80-92 mass% is still more preferable. When it is 60% by mass or more, the curing shrinkage becomes good (the curing shrinkage rate is reduced). When the content is 95% by mass or less, the content of the monomer (B) having an ethylenically unsaturated group in the molecule is relatively increased, and curability and adhesion are improved.

(Monomer (B) having an ethylenically unsaturated group in the molecule)
The liquid photocurable resin composition of the present invention contains a monomer (B) having an ethylenically unsaturated group in the molecule. If the monomer (B) is not included, the liquid photocurable composition is inferior in curability and adhesion. Moreover, when there is little content of a monomer (B), cure shrinkage will become favorable.
From said viewpoint, content of the monomer (B) which has an ethylenically unsaturated group in the molecule | numerator in an ethylenically unsaturated bond containing component (1) is 5-40 with respect to the total amount of (1) component. % By mass is preferable, 7 to 25% by mass is more preferable, and 8 to 20% by 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.

[Monomer (b1) having one ethylenically unsaturated 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, R ¹ and R ² each independently represent an ethylene group or a propylene group, m and n each independently represent an integer of 1 to 5, and each of m and n is 2 or more, A plurality of R ¹ —O may be the same or different, and a plurality of R ² —O may be the same or different.) Diacrylate of an alkylene oxide adduct of bisphenol A represented by the general formula (b)

(Wherein a and b are each 1), an epichlorohydrin-modified product of bisphenol A and an acrylic ester addition product, general formula (c)

(However, in the formula, R ³ and R ⁴ each independently represent an ethylene group or a propylene group, c and d each independently represent an integer of 1 to 5, and each of c and d is 2 or more, 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.) Diacrylate of an alkylene oxide adduct of phosphoric acid represented by the general formula (d)

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

(Wherein, 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 the formula, R ⁵ represents an ethylene group or a propylene group, each of three i independently represents an integer of 1 to 5, and when i is 2 or more, a plurality of R ⁵ —O may be the same. A triacrylate of an alkylene oxide adduct of phosphoric acid represented by general formula (g)

(In the formula, R ⁶ , R ⁷ and R ⁸ each independently represents an ethylene group or a propylene group, j, k and p each independently represent an integer of 1 to 3, j, k and p Are each two or more, a plurality of R ⁶ —O, R ⁷ —O and R ⁸ —O may be the same or different from each other.) Is mentioned.
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.

(Transmittance of component containing ethylenically unsaturated bond (1))
In the ethylenically unsaturated bond-containing component (1), the transmittance of the maximum absorption wavelength existing in the range of 370 to 420 nm of the photopolymerization initiator (2) is 88% or more. If it is less than 88%, 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 still more preferably 91% 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 ethylenically unsaturated bond-containing component (1) , the PET film is covered, and after UV exposure, the PET film is peeled off to form a film having a thickness of 100 μm. Got. Using this film as a sample, transmittance in the range of 300 to 400 nm was 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 97-99.99.95 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 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-di Enylethane-1-one (maximum absorption wavelength: 340 nm), ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl]-, 1- (0-acetyloxime), Mixture of 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 the concentration is 5% by mass or more, it becomes a cause of coloring of the cured product. Moreover, the light-shielding part is not fully hardened as it is 0.01 mass% or less.

<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 (B) 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 absorbed sufficiently. 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 (B) is sufficiently exhibited, and the light shielding portion 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. Of the coumarins, hydroxymethylcoumarins such as 7-hydroxy-4-methylcoumarin and 4-hydroxy-7-methylcoumarin are preferred from the viewpoint of further 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% by mass is more preferable, and 0.01 to 0.5% by mass is particularly 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.

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 particularly preferable. The viscosity is a value measured from an E-type viscometer (RE-80L manufactured by Toki Sangyo Co., Ltd.) using a 3 ° cone rotor at 0.5 rpm.

[Optical member]
The optical member of the present invention is obtained by curing the above-mentioned liquid photocurable resin composition 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]
An image display device according to 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 resin layer existing between the image display unit and the protective panel. In the image display device having a laminated 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 portion 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 for manufacturing an image display device, an image display unit or touch panel having an image display portion and a protective panel having a light shielding portion along the outer peripheral edge are arranged to face each other, and a liquid photocurable resin composition is placed in the gap between them. A method for producing an image display device, wherein the liquid photocurable resin composition is cured by interposing the liquid photocurable resin composition, wherein the liquid photocurable resin composition is interposed, and light irradiation is performed at least from the protective panel surface side. It is to be cured.
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, more preferably 95% or more with respect to light rays in the visible light region (wavelength: 380 to 780 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 by 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. Possible image display devices are 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) Polymer having ethylenically unsaturated bond in molecule (A)
(Urethane acrylate 1)
Urethane acrylate 1 was synthesized as follows.
Polypropylene glycol (molecular weight 2000) 1225.4 g (0.613 mol), unsaturated fatty acid hydroxyalkyl ester modified ε-caprolactone (Placcel FA2D: Daicel) in a reaction vessel equipped with a cooling tube, thermometer, stirring device, dropping funnel and air injection tube Chemical Industries, Ltd., molecular weight: 344) 68.8 g (0.2 mol), butanol 52.3 g (0.71 mol), p-methoxyphenol 0.5 g as a polymerization inhibitor, and dibutyltin dilaurate 0.3 g as a catalyst. I put it in. After raising the temperature to 70 ° C while flowing air, stirring at 70 to 75 ° C, TMDI (mixture of 2,2,4-trimethylhexamethylene diisocyanate and 2,4,4-trimethylhexamethylene diisocyanate, mixing ratio: 4: 6 (mass ratio)) 209.8 g (1 mol) was uniformly added dropwise over 2 hours to carry out the reaction.
When the reaction was completed for 5 hours after completion of the dropping, the reaction was terminated by confirming that the isocyanate had disappeared by IR measurement. Polyurethane acrylate having polypropylene glycol and TMDI as repeating units and having an ethylenically unsaturated bond (weight) The average molecular weight was 7,000, the average number of functional groups was 0.5 (calculated value from the charged amount)).

(Urethane acrylate 2)
Urethane acrylate 2 was synthesized as follows.
2450.8 g (0.613 mol) of polypropylene glycol (molecular weight 4000), unsaturated fatty acid hydroxyalkyl ester modified ε-caprolactone (Placcel FA2D: Daicel) in a reaction vessel equipped with a cooling tube, thermometer, stirring device, dropping funnel and air injection tube Chemical Industry Co., Ltd., molecular weight: 344) 68.8 g (0.2 mol), p-methoxyphenol 0.5 g as a polymerization inhibitor, and dibutyltin dilaurate 0.3 g as a catalyst were taken. After raising the temperature to 70 ° C while flowing air, stirring at 70 to 75 ° C, TMDI (mixture of 2,2,4-trimethylhexamethylene diisocyanate and 2,4,4-trimethylhexamethylene diisocyanate, mixing ratio: 4: 6 (mass ratio)) 209.8 g (1 mol) was uniformly added dropwise over 2 hours to carry out the reaction.
When the reaction was completed for 5 hours after completion of the dropping, the reaction was terminated by confirming that the isocyanate had disappeared by IR measurement. Polyurethane acrylate having polypropylene glycol and TMDI as repeating units and having an ethylenically unsaturated bond (weight) An average molecular weight of 12,000 and an average number of functional groups = 0.5 (calculated value)) were obtained.

(2) Monomer (b1) having one ethylenically unsaturated group in the molecule
FA-314A: manufactured by Hitachi Chemical Co., Ltd. (nonylphenoxypolyethylene glycol acrylate, molecular weight: 452 (calculated assuming the number of ethylene glycol chains as 4))
Acryloylmorpholine: manufactured by Kojin, molecular weight: 141
4-hydroxybutyl acrylate: manufactured by Hitachi Chemical Co., Ltd., molecular weight: 144

(3) Photopolymerization initiator (2)
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.
Irgacure-184 (trade name); 1-hydroxy-cyclohexyl-phenyl-ketone (maximum absorption wavelength 330 nm) (hereinafter sometimes referred to as i-184)
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-4265; mixture of 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide (maximum absorption wavelength 380 nm) and D-1173 (maximum absorption wavelength 330 nm) described later (hereinafter sometimes referred to as i-4265)
Darocur-TPO; 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide (maximum absorption wavelength 380 nm) (hereinafter sometimes referred to as D-TPO)
Irgacure-819; Bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide (maximum absorption wavelength 380 nm) (hereinafter sometimes referred to as i-819)
Irgacure-2959; 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one (maximum absorption wavelength 280 nm) (hereinafter referred to as i-2959) is there)
Irgacure-907; 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one (maximum absorption wavelength 300 nm) (hereinafter sometimes referred to as i-907)
Irgacure-369; 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1 (maximum absorption wavelength 320 nm) (hereinafter sometimes referred to as i-369)
Irgacure-379; 2-dimethylamino-2- (4-methyl-benzyl) -1- (4-morpholin-4-yl-phenyl) -butan-1-one (maximum absorption wavelength 320 nm) (hereinafter i-379) Sometimes called)
Darocur 1173; 2-hydroxy-2-methyl-1-phenylpropan-1-one (maximum absorption wavelength 320 nm) (hereinafter sometimes referred to as D-1173)
Irgacure-651; 2,2-dimethoxy-1,2-diphenylethane-1-one (maximum absorption wavelength 340 nm) (hereinafter sometimes referred to as i-651)
Irgacure-OXE02; Ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl]-, 1- (0-acetyloxime) (maximum absorption wavelength 340 nm) (hereinafter i -It may be called -OXE02)
Irgacure-754; Mixture of 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: 345 nm) (hereinafter sometimes referred to as i-754)
Darocur MBF; phenylglyoxylic acid methyl ester (maximum absorption wavelength 350 nm) (hereinafter sometimes referred to as D-MBF)

(4) Phosphor (3)
7-hydroxy-4-methylcoumarin: manufactured by Wako Pure Chemical Industries, Ltd. anthracene: manufactured by Wako Pure Chemical Industries, Ltd. The excitation wavelength and fluorescent wavelength of each phosphor (3) are as shown in Tables 1 and 2.

<Example 1>
Urethane acrylate 1 (32.24 g) and urethane acrylate 2 (57.31 g) as the polymer (A), FA-314 (3.98 g), acryloylmorpholine (2.49 g) and 4- Hydroxybutyl acrylate (3.48 g), i-1870 (0.25 g) as a photopolymerization initiator (2), and 7-hydroxy-4-methylcoumarin (0.01 g) as a phosphor (3) were added to a screw tube. The mixture was stirred with a self-revolving mixer to obtain a liquid photocurable resin composition.

<Examples 2 to 10>
In Examples 2-10, the liquid photocurable resin composition was obtained by the same method as Example 1 except having adjusted and changed photoinitiator (2) and fluorescent substance (3) as shown in Table 1.

<Comparative Examples 1-11>
In Comparative Examples 1-11, the liquid photocurable resin composition was obtained by the same method as Example 1 except having adjusted and changed the compounding quantity as shown in Table 1.

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

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

<Evaluation>
(Transmittance)
The transmittance (spectral transmittance value) of the ethylenically unsaturated bond-containing component (1) was measured based on the method described in Japanese Industrial Standard Z8722. Specifically, a spacer having a thickness of 100 μm is arranged on the PET film, and after pouring the ethylenically unsaturated bond-containing component (1) , the PET film is covered, and after UV exposure, the PET film is peeled off, A film having a thickness of 100 μm was obtained. Using this film as a sample, transmittance in the range of 300 to 400 nm was measured with a spectrophotometer (manufactured by Hitachi, Ltd., U-3310 type).

(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 hole of 3 cm × 3 cm was laid on a glass of 10 × 10 cm, and after filling the photoresin composition in the hole, the glass was covered with 10 cm × 10 cm of glass from above. Next, half of the 3 cm × 3 cm resin 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 (a vertical exposure machine manufactured by Kitamura, a high power metal halide lamp). Thereafter, the black cloth and the cover glass were removed, and the cured sample was taken out. Among the samples, the length (mm) cured to the shadow part side of the boundary between the shadow part and the light irradiation part was measured as “cured length”.
The liquid photocurable resin compositions obtained in Examples 1 to 10 were excellent in the curability of the shadow portion. Further, the total light transmittance was high and the transparency was excellent. On the other hand, the shadow part did not harden | cure the liquid photocurable resin composition obtained by Comparative Examples 1-11.

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)

Component (1) having an ethylenically unsaturated bond containing a polymer (A) having an ethylenically unsaturated group in the molecule, a monomer (B) having an ethylenically unsaturated group in the molecule, and a photopolymerization initiator (2),
A liquid photocurable resin composition comprising
Furthermore, the phosphor (3) is included,
The photopolymerization initiator (2) has a maximum absorption wavelength in the range of 370 to 420 nm,
The liquid photocurable resin composition whose transmittance | permeability of the ethylenically unsaturated bond containing component (1) in the said maximum absorption wavelength is 88% or more. The liquid photocurable resin composition according to claim 1 , wherein the phosphor (3) has an excitation wavelength in the range of 300 to 400 nm and a fluorescence wavelength in the range of 350 to 450 nm. The liquid photocurable resin composition according to claim 1 or 2 , wherein the phosphor (3) is at least one selected from the group consisting of pyrene, benzopyrene, perylene, anthracene, naphthalene, phenanthrene, and coumarin. The content of the fluorescent substance (3) is, according to any one of claims 1 to 3, which is 0.001 parts by mass with respect to the ethylenically unsaturated bond-containing component (1) 100 parts by weight Liquid photocurable resin composition. The liquid photocurable resin composition according to any one of claims 1 to 4 , wherein the polymer (A) having an ethylenically unsaturated bond in the molecule is a urethane polymer having a (meth) acryloyl group. The urethane polymer having the (meth) acryloyl group is further converted into a compound obtained by reacting (i) a diol compound with (ii) a compound having an isocyanate group, and (iii) a monohydroxy (meth) acrylate, (iv The liquid photocurable resin composition according to claim 5, which is a compound obtained by reacting a monocarboxylic acid having a (meth) acryloyl group or a (v) monoisocyanate compound having a (meth) acryloyl group.   The content of the polymer (A) having an ethylenically unsaturated bond in the molecule in the ethylenically unsaturated bond-containing component (1) is 60 to 95% by mass. The liquid photocurable resin composition as described.   8. A gap between an image display unit having an image display unit and a protective panel having a light shielding part along the outer peripheral edge or a gap between a touch panel and a protective panel having a light shielding part along the outer peripheral edge. The liquid photocurable resin composition according to any one of the above.   The optical member formed by hardening | curing the liquid photocurable resin composition of any one of Claims 1-8 by light irradiation. An image display unit having an image display unit;
A protective panel having a light shielding portion along the outer periphery;
An image display device having a laminated structure including a resin layer present between the image display unit and the protective panel,
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 Claims 1-8. An image display unit having an image display unit;
A touch panel;
A protective panel having a light shielding portion along the outer periphery;
An image display device having a laminated structure including a resin layer present between a touch panel and the protective panel,
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 Claims 1-8. 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,
A method for producing an image display device, wherein the liquid photocurable resin composition according to any one of claims 1 to 8 is interposed in the gap, and is cured by light irradiation at least from the protective panel surface side.