CN107735410B

CN107735410B - Photocurable resin composition, display element sealant, liquid crystal display panel, and method for producing liquid crystal display panel

Info

Publication number: CN107735410B
Application number: CN201680038180.XA
Authority: CN
Inventors: 河野大辅; 沟部佑司; 宫崎知也; 村田达司
Original assignee: MITSUI CHEMICAL CO Ltd
Current assignee: MITSUI CHEMICAL CO Ltd
Priority date: 2015-06-30
Filing date: 2016-06-28
Publication date: 2020-02-07
Anticipated expiration: 2036-06-28
Also published as: KR20180011224A; TWI682960B; KR101981422B1; TW201710372A; WO2017002362A1; JP6127223B1; CN107735410A; JPWO2017002362A1

Abstract

The invention aims to provide a photocurable resin composition which has high curability to visible light and can highly inhibit liquid crystal contamination when used as a liquid crystal sealant, for example. The photocurable resin composition of the present invention comprises: a curable compound A having an ethylenically unsaturated double bond in the molecule; and a compound B having an anthraquinone skeleton or a thioxanthone skeleton and 1 or more NHCO groups in a molecule, wherein the NHCO group equivalent represented by the formula (I) is 350g/eq or less. NHCO group equivalent (g/eq) ═ molecular weight/number of NHCO groups contained in 1 molecule · · formula (I).

Description

Photocurable resin composition, display element sealant, liquid crystal display panel, and method for producing liquid crystal display panel

Technical Field

The present invention relates to a photocurable resin composition, a display element sealant, a liquid crystal display panel, and a method for manufacturing a liquid crystal display panel.

Background

In recent years, display panels such as liquid crystal and organic EL have been widely used as image display panels for various electronic devices including mobile phones and personal computers. For example, the liquid crystal display panel includes: the liquid crystal display device includes two transparent substrates provided with electrodes on the surfaces thereof, a frame-shaped sealing member sandwiched between the two transparent substrates, and a liquid crystal material sealed in a region surrounded by the sealing member.

The liquid crystal display panel can be manufactured by, for example, a liquid crystal dropping process. The liquid crystal display panel using the liquid crystal dropping process is manufactured as follows: (1) a liquid crystal sealant is applied to the inner edge of the transparent substrate to form a frame for filling the liquid crystal, (2) the liquid crystal is dropped into the frame, (3) the two substrates are overlapped under high vacuum in a state where the liquid crystal sealant is not cured, and then (4) the liquid crystal sealant is cured.

Thus, in the liquid crystal dropping process, photocuring or thermal curing is performed in a state where the uncured liquid crystal sealing agent is in contact with the liquid crystal material. Therefore, the liquid crystal sealing agent is required to have not only high curability but also reduced contamination of the liquid crystal material.

As a liquid crystal sealing agent used in a liquid crystal dropping process, a photocurable resin composition containing a compound having a (meth) acryloyl group in a molecule and an anthraquinone derivative as a photopolymerization initiator has been proposed (for example, patent document 1). Further, there has been proposed a photocurable resin composition containing a photopolymerizable oligomer and a compound B obtained by reacting hydroxythioxanthone with a compound having 2 or more epoxy groups in the molecule as a photopolymerization initiator (for example, patent document 2). Further, a sealant for a liquid crystal display element, which contains a curable resin and a compound obtained by reacting an oxime ester with a polyfunctional isocyanate as a photopolymerization initiator, has been proposed (for example, patent document 3).

Documents of the prior art

Patent document

Patent document 1: international publication No. 2007/074782

Patent document 2: international publication No. 2012/077720

Patent document 3: japanese patent laid-open No. 2014-98763

Disclosure of Invention

Problems to be solved by the invention

However, the composition disclosed in patent document 3 contains a photopolymerization initiator having low absorption of light in the visible light region, and thus has low curability against light in the visible light region. The compositions disclosed in patent documents 1 and 2 contain a photopolymerization initiator having an anthraquinone skeleton or a thioxanthone skeleton, and therefore have good curability against light in the visible light region, but it is required that elution of the photopolymerization initiator into a liquid crystal material can be further reduced. Thus, it is desired to provide a photocurable resin composition which has high curability against light in the visible light region and can highly suppress liquid crystal contamination.

The present invention has been made in view of the above problems, and an object thereof is to provide a photocurable resin composition which has high curability against visible light and can highly suppress contamination of liquid crystal when used as, for example, a display element sealant, particularly a liquid crystal sealant.

Means for solving the problems

[1] A photocurable resin composition comprising: a curable compound A having an ethylenically unsaturated double bond in the molecule; and a compound B having an anthraquinone skeleton or a thioxanthone skeleton and an NHCO group in a molecule, wherein the NHCO group equivalent represented by the formula (I) is 350g/eq or less,

NHCO group equivalent (g/eq) ═ molecular weight/number of NHCO groups contained in 1 molecule · · formula (I).

[2] The photocurable resin composition according to [1], wherein the compound B has 3 or more NHCO groups in a molecule.

[3] The photocurable resin composition according to [1] or [2], wherein the compound B has a biuret skeleton or an allophanate skeleton in a molecule.

[4] The photocurable resin composition according to any one of [1] to [3], wherein the compound B is represented by the following formula (4) or formula (5),

[ solution 1]

(in the formulae (4) and (5), L₁Each independently represents a single bond, an alkylene group having 1 to 10 carbon atoms, an alkyleneoxy group having 1 to 10 carbon atoms, an alkylenethio group having 1 to 10 carbon atoms, an arylene group having 6 to 10 carbon atoms, an aryleneoxy group having 6 to 10 carbon atoms or an arylenethio group having 6 to 10 carbon atoms, X represents an organic group derived from a compound having at least p isocyanate groups in the molecule, and p represents an integer of 1 to 5).

[5] The photocurable resin composition according to any one of [1] to [4], wherein the compound B further has an ethylenically unsaturated double bond in a molecule, and the curable compound A has no anthraquinone skeleton or thioxanthone skeleton.

[6] The photocurable resin composition according to any one of [1] to [5], wherein the content of the compound B is 0.01 to 10% by mass relative to the curable compound A.

[7] The photocurable resin composition according to any one of [1] to [6], wherein the curable compound A further has an epoxy group in a molecule.

[8] The photocurable resin composition according to any one of [1] to [7], further comprising a thermosetting compound C having an epoxy group in a molecule and a thermosetting agent D, wherein the thermosetting compound C is different from the curable compound A.

[9] The photocurable resin composition according to [8], wherein the thermal curing agent D is at least one selected from the group consisting of a dihydrazide-based thermally latent curing agent, an imidazole-based thermally latent curing agent, an amine adduct-based thermally latent curing agent, and a polyamine-based thermally latent curing agent.

[10] A display element sealant comprising the photocurable resin composition according to any one of [1] to [9 ].

[11] A liquid crystal sealing agent comprising the photocurable resin composition according to any one of [1] to [9 ].

[12] The liquid crystal sealing agent according to [11], which is a liquid crystal sealing agent for a liquid crystal dropping process.

[13] A method for manufacturing a liquid crystal display panel includes: forming a seal pattern on one substrate using the liquid crystal sealant according to [11] or [12 ]; dropping a liquid crystal in a region of the seal pattern or on another substrate paired with the one substrate in a state where the seal pattern is not cured; a step of overlapping the one substrate and the other substrate with the seal pattern interposed therebetween; and curing the seal pattern.

[14] The method of manufacturing a liquid crystal display panel according to [13], wherein the step of curing the seal pattern includes a step of curing the seal pattern by irradiating the seal pattern with light.

[15] The method of manufacturing a liquid crystal display panel according to [14], wherein the light irradiated to the seal pattern includes light in a visible light region.

[16] The method for manufacturing a liquid crystal display panel according to [14] or [15], wherein the step of curing the seal pattern further includes a step of curing the seal pattern by heating the seal pattern irradiated with light.

[17] A liquid crystal display panel, comprising: a pair of substrates, a frame-shaped sealing member disposed between the pair of substrates, and a liquid crystal layer filled in a space surrounded by the sealing member between the pair of substrates, wherein the sealing member is a cured product of the liquid crystal sealing agent according to [11] or [12 ].

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, a photocurable resin composition which has high curability against visible light and can highly suppress contamination of liquid crystal when used as, for example, a display element sealant, particularly a liquid crystal sealant, can be provided.

Detailed Description

1. Photocurable resin composition

The photocurable resin composition of the present invention comprises a curable compound a and a compound B, and may further comprise a thermosetting compound C and a thermosetting agent D as required.

1-1. curable Compound A

The curable compound a contained in the photocurable resin composition of the present invention is a compound having an ethylenically unsaturated double bond in the molecule. The compound having an ethylenically unsaturated double bond in the molecule is preferably a compound having a (meth) acryloyl group in the molecule. The number of (meth) acryloyl groups per 1 molecule is 1 or 2 or more. The compound having a (meth) acryloyl group in a molecule may be any of a monomer, an oligomer, or a polymer. (meth) acryloyl means acryloyl or methacryloyl, (meth) acrylate means acrylate or methacrylate. However, the curable compound a does not have an anthraquinone skeleton or a thioxanthone skeleton.

Examples of 1 compound having 1 (meth) acryloyl group in the molecule include: alkyl (meth) acrylates such as methyl (meth) acrylate, ethyl (meth) acrylate, and 2-hydroxyethyl (meth) acrylate.

Examples of 1 compound having 2 or more (meth) acryloyl groups in the molecule include: di (meth) acrylates of polyethylene glycol, propylene glycol, polypropylene glycol, and the like; di (meth) acrylate ester of tris (2-hydroxyethyl) isocyanurate; di (meth) acrylate of diol obtained by adding 4 or more moles of ethylene oxide or propylene oxide to 1 mole of neopentyl glycol; di (meth) acrylate of diol obtained by adding 2 moles of ethylene oxide or propylene oxide to 1 mole of bisphenol a; di-or tri (meth) acrylate of triol obtained by adding 3 or more moles of ethylene oxide or propylene oxide to 1 mole of trimethylolpropane; di (meth) acrylate of diol obtained by adding 4 or more moles of ethylene oxide or propylene oxide to 1 mole of bisphenol a; tris (2-hydroxyethyl) isocyanurate tri (meth) acrylate; trimethylolpropane tri (meth) acrylate, or an oligomer thereof; pentaerythritol tri (meth) acrylate or an oligomer thereof; poly (meth) acrylates of dipentaerythritol; tris (acryloyloxyethyl) isocyanurate; caprolactone-modified tris (acryloyloxyethyl) isocyanurate; caprolactone-modified tris (methacryloyloxyethyl) isocyanurate; polyacrylates or polymethacrylates of alkyl-modified dipentaerythritol; a caprolactone-modified polyacrylate or polymethacrylate of dipentaerythritol; hydroxyl trimethyl acetic acid neopentyl glycol diacrylate or dimethacrylate; caprolactone-modified neopentylglycol di (meth) acrylate hydroxyl pivalate; ethylene oxide-modified phosphoric acid acrylate or dimethacrylate; ethylene oxide-modified alkylated phosphoric acid (meth) acrylates; neopentyl glycol, trimethylolpropane, oligomeric (meth) acrylates of pentaerythritol, and the like.

The curable compound a may further have an epoxy group in the molecule. The number of epoxy groups per 1 molecule is 1 or 2 or more. If the curable compound a has not only a (meth) acryloyl group but also an epoxy group in the molecule, it is possible to impart photocurability and thermosetting properties to the photocurable resin composition containing the curable compound a. This improves the curability of the cured product.

The compound having a (meth) acryloyl group and an epoxy group in a molecule may be, for example, glycidyl (meth) acrylate obtained by reacting an epoxy compound with (meth) acrylic acid in the presence of a basic catalyst.

The epoxy compound to be reacted may be a polyfunctional epoxy compound having 2 or more epoxy groups in the molecule, and is preferably a difunctional epoxy compound in view of suppressing the decrease in adhesiveness of a cured product of the photocurable resin composition due to an excessively high crosslinking density. Examples of difunctional epoxy compounds include: bisphenol epoxy compounds (bisphenol a, bisphenol F, 2' -diallylbisphenol a, bisphenol AD, hydrogenated bisphenol, etc.), biphenyl epoxy compounds, and naphthalene epoxy compounds. Among these, bisphenol epoxy compounds of bisphenol a type and bisphenol F type are preferable from the viewpoint of good coatability. The bisphenol epoxy compound has advantages such as excellent coatability, compared with the biphenyl ether epoxy compound.

The compound having a (meth) acryloyl group and an epoxy group in a molecule may be one kind or a combination of two or more kinds.

The compound a1 having a (meth) acryloyl group and no epoxy group in the molecule and the compound a2 having a (meth) acryloyl group and an epoxy group in the molecule may be combined. Thus, when the photocurable resin composition further contains an epoxy compound as the thermosetting compound C, the compatibility of the epoxy compound with the compound a1 having a (meth) acryloyl group and no epoxy group in the molecule can be improved. Further, since the photocurable resin composition contains the compound B having an appropriate hydrophilicity, even if the compound a1 exhibiting hydrophobicity compared with the compound a2 is contained, elution of the photocurable resin composition into a display element, particularly a liquid crystal, can be suppressed. The mass ratio of compound a2 to compound a1 may be, for example, a2/a1 of 1/0.4 to 1/0.6.

The content of the compound a2 having a (meth) acryloyl group and an epoxy group in the molecule is not particularly limited, and may be, for example, 30 mass% or more with respect to the curable compound a.

The weight average molecular weight of the curable compound A is preferably about 310 to 1000. The weight average molecular weight of the curable compound a can be measured, for example, in terms of polystyrene by Gel Permeation Chromatography (GPC).

The content of the curable compound a is preferably 40 to 80% by mass, and more preferably 50 to 75% by mass, relative to the photocurable resin composition.

1-2. Compound B

The compound B contained in the photocurable resin composition of the present invention has an anthraquinone skeleton or a thioxanthone skeleton and an NHCO group in the molecule.

The anthraquinone skeleton or thioxanthone skeleton contained in the compound B can be excited by well absorbing light in the visible light region, and a hydrogen abstraction reaction from the curable compound a occurs. Since the NHCO group contained in the compound B exhibits appropriate hydrophilicity, it is preferable to suppress elution of the compound B in the liquid crystal material. Therefore, the compound B can function preferably as a photopolymerization initiator for a photocurable resin composition used as a sealing agent for a display element, particularly a liquid crystal sealing agent.

The number of anthraquinone skeleton or thioxanthone skeleton per 1 molecule is 1 or 2 or more. From the viewpoint of obtaining sufficient curability against light in the visible light region even if the content of the compound B is small, the number of anthraquinone skeleton or thioxanthone skeleton per 1 molecule is preferably 2 or more.

The number of NHCO groups per 1 molecule is 1 or 2 or more. From the viewpoint of highly suppressing elution of the compound B in the liquid crystal material, the number of NHCO groups per 1 molecule is preferably 2 or more, more preferably 3 or more. From the viewpoint of ease of increasing the number of NHCO groups per 1 molecule, compound B preferably has a biuret skeleton (-NHCO (N-) CONH-) or an allophanate skeleton (-NHCO (N-) COO-).

The compound B may further have an ethylenically unsaturated double bond in the molecule. If the compound B further has an ethylenically unsaturated double bond in the molecule, the compound B and the curable compound A undergo a polymerization reaction during curing, for example, and elution of the compound B into the liquid crystal material is more easily suppressed.

The compound B is obtained by reacting "an anthraquinone compound B1 having a hydroxyl group in the molecule or a thioxanthone compound B2 having a hydroxyl group in the molecule" with "a compound B3 having an isocyanate group in the molecule".

"the anthraquinone compound b1 having a hydroxyl group in the molecule" is represented by the following formula (1). "the thioxanthone compound b2 having a hydroxyl group in the molecule" is represented by the following formula (2).

[ solution 2]

L of the formulae (1) and (2)₁Each independently a single bond or a divalent organic group. The divalent organic group may be: an alkylene group having 1 to 10 carbon atoms (e.g., methylene, ethylene, etc.), an alkyleneoxy group having 1 to 10 carbon atoms (e.g., methyleneoxy, ethyleneoxy, etc.), an alkylenethio group having 1 to 10 carbon atoms (e.g., methylenethio (-S-CH)₂-) ethylenethio (-S-CH)₂CH₂-) and the like), an arylene group having 6 to 10 carbon atoms (for example, a phenylene group), an arylene group having 6 to 10 carbon atomsAn oxy group (e.g., a phenyleneoxy group) or an arylenethio group having 6 to 10 carbon atoms (e.g., a phenylenesulfide group). Among them, in the anthraquinone skeleton, thioxanthone skeleton combined with sulfide (-S-), easy absorption of long wavelength side light, so preferably C1 ~ 10 alkylene sulfide or C6 ~ 10 arylene sulfide.

M in the formulae (1) and (2) is an integer of 1 or more, preferably 1. - (L)₁-OH) may be bonded to any one of carbon atoms at positions 1 to 8 of the anthraquinone skeleton or the thioxanthone skeleton, preferably to a carbon atom at position 2 or 7.

The compound represented by formula (1) is preferably represented by formula (1'); the compound represented by the formula (2) is preferably represented by the following formula (2').

[ solution 3]

-L of formula (1 ') and formula (2')₁the-OH group may be bonded to any one of carbon atoms at positions 1 to 8, preferably carbon atoms at positions 2 or 7 of the anthraquinone skeleton or the thioxanthone skeleton.

"the compound b3 having an isocyanate group in the molecule" is a compound having 1 or 2 or more isocyanate groups in the molecule. The NHCO group equivalent of the obtained compound B is preferably a compound having 2 or more isocyanate groups in the molecule, in terms of ease of adjustment to a certain value or less. The number of isocyanate groups per 1 molecule is not particularly limited, but is preferably 2 to 4, more preferably 2 to 3, in terms of ease of setting the NHCO group equivalent of the compound B to a certain value or less.

The compound having 2 or more isocyanate groups in the molecule preferably has an NHCO group in the molecule, more preferably has a biuret skeleton (-NHCO (N-) CONH-), an allophanate skeleton (-NHCO (N-) COO-) or an urethane skeleton, and still more preferably has a biuret skeleton or an allophanate skeleton. That is, the compound having 2 or more isocyanate groups in the molecule can be represented by, for example, the following formula (3a) or formula (3 b).

[ solution 4]

R of formula (3a)₁And R of formula (3b)₂Each is a linear, branched or cyclic saturated aliphatic or aromatic hydrocarbon group which may have an NHCO group. R₁And R₂The number of the NHCO group contained in (a) is 0 or 1 or more, preferably 2 or more. R₁And R₂Preferably, the compound has a structure represented by the following formula (α), formula (β) or formula (γ), more preferably, formula (α) or formula (β).

[ solution 5]

R of formula (γ)₃Represents a saturated aliphatic hydrocarbon group or an aromatic hydrocarbon group derived from a polyhydric alcohol described later, and n is an integer of 1 or more)

The compound having 2 or more isocyanate groups in the molecule may be, for example, a biuret or allophanate obtained from a diisocyanate; or a urethane prepolymer which is obtained by reacting a polyisocyanate with a polyol and has an isocyanate group at a molecular terminal.

Examples of the diisocyanate to be a raw material of the biuret or allophanate body include: aliphatic diisocyanates having 1 to 10 carbon atoms such as tetramethylene diisocyanate, 1, 6-hexamethylene diisocyanate, trimethylhexamethylene diisocyanate and the like; alicyclic diisocyanates having 6 to 15 carbon atoms such as cyclohexylene diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate and the like; and aromatic diisocyanates having 6 to 15 carbon atoms such as tolylene diisocyanate, phenylene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate, and naphthalene diisocyanate.

The polyisocyanate used as a raw material of the urethane prepolymer is a polyfunctional aliphatic, alicyclic or aromatic isocyanate, and examples thereof include the above-mentioned diisocyanate. Examples of the polyol to be a raw material of the urethane prepolymer include: aliphatic polyhydric alcohols such as ethylene glycol, 1, 3-propylene glycol, polyethylene glycol, dipropylene glycol, and pentaerythritol; alicyclic polyols such as 1, 4-cyclohexanedimethanol, 1, 4-cyclohexanediol, hydrogenated bisphenol a and hydrogenated bisphenol F; aromatic polyols such as bisphenol a and bisphenol F, and the like.

The compound B is preferably obtained by reacting a compound represented by the formula (1 ') or the formula (2') with a compound having 2 or more isocyanate groups in the molecule; more preferably, the compound represented by the formula (1 ') or the formula (2') is reacted with the compound represented by the formula (3a) or the formula (3b) (preferably, R)₁Or R₂A compound having an NHCO group) "by a reaction.

The following reaction scheme shows an example in which a compound represented by formula (1') is reacted with a compound represented by formula (3B) to obtain compound B.

[ solution 6]

In addition to the reaction of the compound represented by the formula (1 ') or the formula (2') with the compound having 2 or more isocyanate groups in the molecule, the hydroxyl group-containing compound b4 may be further reacted.

The "hydroxyl group-containing compound b 4" is a compound having a hydroxyl group in the molecule. The hydroxyl group of the compound having a hydroxyl group in the molecule may react with the isocyanate group of the "compound having 2 or more isocyanate groups in the molecule" to form further-O-CONH-. Examples of the compound having a hydroxyl group in the molecule include monohydric alcohols having 1 to 20 carbon atoms such as methanol, ethanol, propanol, butanol, pentanol, hexanol, and 1-octadecanol.

The compound having a hydroxyl group in the molecule may further have an ethylenically unsaturated double bond. Thus, an ethylenically unsaturated double bond can be introduced into the compound B. Examples of the hydroxyl group-containing compound having an ethylenically unsaturated double bond in the molecule include (meth) acrylates substituted with a hydroxyl group such as 4-hydroxybutyl acrylate.

Among them, the compound B is preferably represented by the following formula (4) or formula (5).

[ solution 7]

L of formulae (4) and (5)₁And L of formulae (1) and (2)₁Are respectively the same meaning.

X in the formulae (4) and (5) represents an organic group derived from a compound having at least p isocyanate groups in the molecule. The group derived from a compound having at least p isocyanate groups in the molecule is preferably a group derived from the above-mentioned compound having 2 or more isocyanate groups in the molecule, and more preferably a divalent group derived from a compound represented by formula (3a) or a trivalent group derived from a compound represented by formula (3 b).

P in the formulae (4) and (5) represents an integer of 1 to 5, preferably 2 or 3.

-L₁The group represented by-O-X may be bonded to any of the carbon atoms at the 1-8 positions of the anthraquinone skeleton or the thioxanthone skeleton, and is preferably bonded to the carbon atom at the 2-or 7-position.

Specific examples of compound B include: a compound obtained by reacting 2- (2-hydroxyethylthio) -9, 10-anthraquinone with a hexamethylene diisocyanate biuret modified product, a compound obtained by reacting 2-hydroxymethylanthraquinone with a hexamethylene diisocyanate biuret modified product, a compound obtained by reacting 2- (2-hydroxyethylthio) -9, 10-anthraquinone with a hexamethylene diisocyanate allophanate modified product, a compound obtained by reacting 2-hydroxythioxanthone with a hexamethylene diisocyanate biuret modified product, a compound obtained by reacting 2-hydroxythioxanthone with a hexamethylene diisocyanate allophanate modified product, a compound obtained by reacting 2- (2-hydroxyethylthio) -thioxanthen-9-one with a hexamethylene diisocyanate biuret modified product, a compound obtained by reacting a mixture of 2- (2-hydroxyethylthio) -thioxanthen-9-one and a hexamethylene diisocyanate biuret modified product, A compound obtained by reacting 2- (2-hydroxyethylthio) -thioxanthen-9-one with an allophanate modification of hexamethylene diisocyanate, a compound obtained by further reacting these compounds with stearyl alcohol or 4-hydroxybutyl acrylate, and the like.

In order to suppress contamination of the liquid crystal material by the compound B, it is also considered to increase the molecular weight of the compound B. However, when the molecular weight of the compound B is merely increased, the content ratio of the anthraquinone skeleton and the thioxanthone skeleton contributing to light absorption in 1 molecule may be relatively decreased. As a result, in order to obtain light absorption properties of a certain level or more, the content of the compound B needs to be increased, and the liquid crystal material may be contaminated. Therefore, in the present invention, it is preferable to set the ratio of the NHCO group contained per 1 molecule to be constant or more (to set the NHCO group equivalent to be constant or less).

That is, the NHCO group equivalent of the compound B is preferably 350g/eq or less. When the equivalent of the NHCO group of the compound B is 350g/eq or less, the number of NHCO groups contained in the compound B is large, and therefore the hydrophilicity is moderately improved, and when the photocurable resin composition is used as a liquid crystal sealing agent, elution of the compound B into a liquid crystal material can be suppressed. The equivalent weight of the NHCO group of the compound B is more preferably 200 to 350g/eq, still more preferably 230 to 330 g/eq. When the NHCO group equivalent of the compound B is 200g/eq or more, the moisture resistance of a cured product of the photocurable resin composition is hardly impaired. The NHCO group equivalent of compound B is defined by the following formula (I).

NHCO group equivalent (g/eq) ═ molecular weight/number of NHCO groups contained in 1 molecule · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · ·

In order to set the NHCO group equivalent of the compound B in the above range, it is preferable to react the "compound represented by the formula (1 ') or the formula (2') with the" compound having 2 or more isocyanate groups in the molecule "as described above; more preferably, the compound represented by the formula (1 ') or the formula (2') is reacted with the compound represented by the formula (3a) or the formula (3b) (preferably, R)₁Or R₂Compound having NHCO group) "is reacted.

The molecular weight of the compound B is preferably 500 or more and 5000 or less, for example. The "molecular weight" of compound B is defined as the "relative molecular mass" of the molecular structure of a main peak when the main peak is detected by High Performance Liquid Chromatography (HPLC); when the main peak is not detected, the molecular weight is defined as "weight average molecular weight".

Specifically, a sample solution was prepared by dissolving compound B in THF (tetrahydrofuran), and High Performance Liquid Chromatography (HPLC) measurement was performed under the following measurement conditions. Then, the presence or absence of a main peak (main detection peak) was confirmed among peaks detected at a detection wavelength of 400 nm. The "main peak (main detection peak)" means a peak having the highest intensity (peak having the highest height) among all peaks detected at a detection wavelength of 400 nm.

(conditions for HPLC measurement)

The device comprises the following steps: acquisty (TM) UPLC class H system manufactured by waters

Column: acquity UPLC BEH C18, 2.1mmID × 100mm, particle size: 1.7 μm

Mobile phase: a: acetonitrile

B: 5mM ammonium acetate in water

A/B60/40 (0 min. 4 min.)

95/5 (4-9 minutes)

95/5 (9-10 minutes)

Flow rate: 0.4 mL/min

A PDA detector: measuring wavelength: 190 nm-500 nm, extraction wavelength: 400nm

Then, the relative molecular mass of the detected main peak corresponding to the peak top was determined by Liquid Chromatography mass spectrometry (LC/MS).

(LC/MS measurement conditions)

The device comprises the following steps: acquisty (TM) class H system/SQ detector manufactured by waters

Column: acquisty UPLC BEH C18, 2.1mmID × 100mm

Particle size: 1.7 μm

Mobile phase: a: acetonitrile

B: 5mM ammonium acetate in water

A/B60/40 (0 min. 4 min.)

95/5 (4-9 minutes)

95/5 (9-10 minutes)

Flow rate: 0.4 mL/min

Ionization: ESI (electrospray ionization), Positive/negative ion measurement

The weight average molecular weight of compound B can be measured in terms of standard polystyrene by Gel Permeation Chromatography (GPC).

If the molecular weight of the compound B is 500 or more, it is difficult to dissolve in the liquid crystal, and thus the contamination of the liquid crystal is easily reduced. If the molecular weight of compound B is 5000 or less, the compatibility with curable compound A is hardly impaired. The molecular weight of compound B is more preferably 500 to 3000, and still more preferably 700 to 1500.

The NHCO group equivalent of compound B can be confirmed by combining High Performance Liquid Chromatography (HPLC) and liquid chromatography mass spectrometry (LC/MS), with NMR measurement or IR measurement. Specifically, the procedure can be performed in the following order.

1) The photocurable resin composition is dissolved in Tetrahydrofuran (THF) to prepare a solution, which is centrifuged by a centrifuge to precipitate particle components such as silica particles and thermoplastic resin particles. The obtained solution was filtered through a filter to remove particulate components, thereby obtaining a sample solution.

2) The sample liquid obtained in 1) above was subjected to High Performance Liquid Chromatography (HPLC) measurement. The method and conditions for the HPLC measurement are the same as those for the HPLC measurement in the measurement of the molecular weight of compound B.

Next, in the HPLC measurement, the relative molecular mass and composition formula corresponding to the peak top of the main peak detected by a detector having a characteristic wavelength of 400nm for the anthraquinone skeleton or the thioxanthone skeleton were measured by liquid chromatography mass spectrometry (LC/MS). The method and conditions for measuring LC/MS are the same as those for measuring LC/MS in the measurement of the molecular weight of Compound B.

3) On the other hand, the sample liquid obtained in 1) above was subjected to NMR measurement or IR measurement. From this, the presence or absence of a spectrum characteristic to the anthraquinone skeleton, the thioxanthone skeleton, or the NHCO group was confirmed, and the chemical structure was determined.

4) The molecular weight obtained in the above 2) and the number of NHCO groups obtained in the above 3) are substituted into the above formula (I) to find the NHCO group equivalent (g/eq).

The compound B may be one or a combination of two or more. For example, a compound having an anthraquinone skeleton in the molecule and a compound having a thioxanthone skeleton in the molecule may be combined.

The content of the compound B is preferably 0.01 to 10% by mass relative to the curable compound a. When the content of the compound B is 0.01% by mass or more, sufficient photocurability can be easily obtained. When the content of the compound B is 10% by mass or less, elution into the liquid crystal material is difficult to occur, and sufficient photocurability is easily obtained.

In particular, when the compound B is a compound having an anthraquinone skeleton in the molecule, the content of the compound B is more preferably 0.1 to 5% by mass, still more preferably 0.1 to 3% by mass, and particularly preferably 0.1 to less than 2% by mass, relative to the curable compound a.

When the compound B is a compound having a thioxanthone skeleton in a molecule, the content of the compound B is more preferably 0.1 to 6% by mass, and still more preferably 0.1 to less than 4% by mass, based on the curable compound a.

1-3.Heat-curing Compounds C

The thermosetting compound C is preferably an epoxy compound having an epoxy group in the molecule. However, the thermosetting compound C is different from the curable compound a. The thermosetting compound C is more preferably an epoxy compound having no (meth) acryloyl group in the molecule. The epoxy compound may be any of a monomer, an oligomer, or a polymer. When the photocurable resin composition is used as a liquid crystal sealing agent, for example, the epoxy compound has low solubility and diffusibility in liquid crystal, and can improve not only the display characteristics of the obtained liquid crystal panel but also the moisture resistance of the cured product.

The epoxy compound may be an aromatic epoxy compound having a weight average molecular weight of 500 to 10000, preferably 1000 to 5000. The weight average molecular weight of the epoxy compound can be measured in terms of polystyrene by Gel Permeation Chromatography (GPC).

Examples of the aromatic epoxy compound include: aromatic polyglycidyl ether compounds obtained by reacting epichlorohydrin with aromatic diols represented by bisphenol a, bisphenol S, bisphenol F, bisphenol AD, and the like, and diols obtained by modifying these with ethylene glycol, propylene glycol, or alkylene glycol; a novolak-type polyglycidyl ether compound obtained by the reaction of a polyphenol represented by a novolak resin derived from phenol or cresol and formaldehyde, a polyalkenyl phenol, a copolymer thereof, or the like, with epichlorohydrin; glycidyl ether compounds of xylylene phenol resins, and the like. Among them, preferred are: cresol novolak type epoxy compounds, phenol novolak type epoxy compounds, bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, trisphenolmethane type epoxy compounds, trisphenolethane type epoxy compounds, trisphenol type epoxy compounds, dicyclopentadiene type epoxy compounds, diphenyl ether type epoxy compounds, and biphenyl type epoxy compounds. The epoxy compound may be one kind or a combination of two or more kinds.

The epoxy compound may be in a liquid state or a solid state. In terms of easily improving the moisture resistance of the cured product, a solid epoxy compound is preferable. The softening point of the solid epoxy compound is preferably 40 ℃ or higher and 150 ℃ or lower. The softening point can be measured by the ring and ball method defined in JIS K7234.

The content of the thermosetting compound C is preferably 3 to 20% by mass relative to the photocurable resin composition. When the content of the thermosetting compound C in the photocurable resin composition is 3% by mass or more, the moisture resistance of a cured product of the photocurable resin composition can be easily and favorably improved. If the content of the thermosetting compound C is 20% by mass or less with respect to the photocurable resin composition, an excessive increase in viscosity of the photocurable resin composition can be suppressed. The content of the thermosetting compound C is more preferably 3 to 15% by mass, and still more preferably 4 to 15% by mass, relative to the photocurable resin composition.

The content of the thermosetting compound C is preferably 3.8 to 50% by mass, more preferably 5 to 30% by mass, based on the curable compound a. When the content of the thermosetting compound C is 5% by mass or more relative to the curable compound a, the moisture resistance and the adhesive strength to the glass substrate of the cured product can be further improved, and when the content is 30% by mass or less, the compatibility with the curable compound a during production can be further improved.

1-4 thermal curing agent D

The heat-curing agent D is a compound which does not cure the heat-curable compound C under ordinary storage conditions (room temperature, visible light, etc.) but cures the compound when heated. The photocurable resin composition containing the thermal curing agent D is excellent in storage stability and thermosetting properties. The heat-curing agent D is preferably an epoxy curing agent.

The epoxy curing agent is preferably an epoxy curing agent having a melting point of 50 ℃ or more and 250 ℃ or less, more preferably an epoxy curing agent having a melting point of 100 ℃ or more and 200 ℃ or less, and still more preferably an epoxy curing agent having a melting point of 150 ℃ or more and 200 ℃ or less, although it depends on the thermosetting temperature from the viewpoint of improving the viscosity stability of the photocurable resin composition and not impairing the moisture resistance of the cured product.

Examples of the epoxy curing agent include: an organic acid dihydrazide heat-latent curing agent, an imidazole heat-latent curing agent, a dicyandiamide heat-latent curing agent, an amine adduct heat-latent curing agent, and a polyamine heat-latent curing agent.

Examples of the organic acid dihydrazide based heat latent curing agent include: adipic acid dihydrazide (melting point 181 ℃ C.), 1, 3-bis (hydrazinocarbonylethyl) -5-isopropylhydantoin (melting point 120 ℃ C.), 7, 11-octadecadienyl-1, 18-dicarbonylhydrazide (melting point 160 ℃ C.), dodecanedioic acid dihydrazide (melting point 190 ℃ C.), and sebacic acid dihydrazide (melting point 189 ℃ C.), and the like. Examples of the imidazole-based heat-latent curing agent include: 2, 4-diamino-6- [2 '-ethylimidazolyl- (1') ] -ethyltriazine (melting point 215 ℃ C. to 225 ℃ C.), 2-phenylimidazole (melting point 137 ℃ C. to 147 ℃ C.), and the like. Examples of the dicyandiamide thermal latent curing agent include dicyandiamide (melting point 209 ℃ C.). The amine adduct-based heat latent curing agent is a heat latent curing agent containing an adduct compound obtained by reacting an amine compound having catalytic activity with an arbitrary compound, and examples thereof include: amicure PN-40 (melting point 110 ℃ C.) produced by Aomoto-know Fine chemistry, Amicure PN-23 (melting point 100 ℃ C.) produced by Aomoto-know fine chemistry, Amicure PN-31 (melting point 115 ℃ C.) produced by Aomoto-know fine chemistry, Amicure PN-H (melting point 115 ℃ C.) produced by Aomoto-know fine chemistry, Amicure MY-24 (melting point 120 ℃ C.) produced by Aomoto-know fine chemistry, and Amicure MY-H (melting point 131 ℃ C.) produced by Aomoto-know fine chemistry. The polyamine-based heat latent curing agent is a heat latent curing agent having a polymer structure obtained by reacting an amine with an epoxy, and examples thereof include: adeka Hardener EH4339S (softening point 120 ℃ C. to 130 ℃ C.) manufactured by ADEKA, and Adeka Hardener EH4357S (softening point 73 ℃ C. to 83 ℃ C.) manufactured by ADEKA, and the like. Among them, dihydrazide-based heat-latent curing agents, imidazole-based heat-latent curing agents, amine adduct-based heat-latent curing agents, and polyamine-based heat-latent curing agents are preferable. The epoxy curing agent may be one kind alone or two or more kinds in combination.

The content of the heat-curing agent D is preferably 3 to 30% by mass, more preferably 3 to 20% by mass, and still more preferably 5 to 20% by mass, relative to the photocurable resin composition. The photocurable resin composition containing the thermal curing agent D may be a one-pack type curable resin composition. The one-pack curable resin composition is excellent in workability because it does not require mixing of a main agent and a curing agent at the time of use.

The content of the heat-curing agent D is preferably 3.8 to 75% by mass, more preferably 3.8 to 50% by mass, and still more preferably 10 to 40% by mass, relative to the curable compound a. When the content of the heat-curing agent D in the curable compound a is 10% by mass or more, the curability of the curable compound a during heating can be easily further improved, and when the content is 40% by mass or less, contamination of the liquid crystal can be easily further suppressed.

The total content of the thermosetting compound C and the thermal curing agent D is preferably 6 to 50% by mass, more preferably 6 to 35% by mass, and still more preferably 6 to 30% by mass, relative to the photocurable resin composition.

1-5. other component E

1-5-1. thermoplastic polymer particles

The photocurable resin composition of the present invention may further contain thermoplastic polymer microparticles as necessary. The thermoplastic polymer fine particles comprise a thermoplastic polymer having a softening point temperature of 50 to 120 ℃ and preferably 70 to 100 ℃ as measured by the ring and ball method, and may have a number average particle diameter of 0.05 to 5 μm and preferably 0.1 to 3 μm. The photocurable resin composition containing such thermoplastic polymer microparticles can alleviate the shrinkage stress generated in a cured product. Further, by setting the number average particle diameter to be not more than the upper limit value, it is possible to prevent the coating stability from being lowered by the thermoplastic polymer fine particles when forming a sealing member having a small line width. The number average particle diameter can be measured by a dry particle size distribution meter.

Examples of the thermoplastic polymer fine particles include fine particles obtained by suspension polymerization of a resin containing an epoxy group and a double bond group and a monomer capable of radical polymerization. Examples of the resin containing an epoxy group and a double bond group include resins obtained by reacting a bisphenol F type epoxy resin with methacrylic acid in the presence of a tertiary amine. Examples of monomers which can be subjected to free-radical polymerization include: butyl acrylate, glycidyl methacrylate, and divinylbenzene.

The content of the thermoplastic polymer fine particles is preferably 5 to 40% by mass, more preferably 7 to 30% by mass, based on the photocurable resin composition. When the content of the thermoplastic polymer fine particles is in the above range, the thermoplastic polymer fine particles desirably relax the shrinkage stress at the time of heat curing of the photocurable resin composition, and the sealing member can be easily formed with a desired line width.

1-5-2. bulking agent

The photocurable resin composition of the present invention may further contain a filler as necessary. The photocurable resin composition containing a filler can be excellent in viscosity, strength of a cured product, linear expansibility, and the like.

Examples of the filler include: inorganic fillers such as calcium carbonate, magnesium carbonate, barium sulfate, magnesium sulfate, aluminum silicate, zirconium silicate, iron oxide, titanium nitride, alumina (alumina), zinc oxide, silica, potassium titanate, kaolin, talc, glass beads, sericite, activated clay, bentonite, aluminum nitride, and silicon nitride. Among them, silica and talc are preferable.

The shape of the filler may be a fixed shape such as a sphere, a plate, or a needle, or may be an indefinite shape. When the filler is spherical, the average primary particle diameter of the filler is preferably 1.5 μm or less, and the specific surface area is preferably 0.5m²/g～20m²(ii) in terms of/g. The average primary particle diameter of the filler can be measured by a laser diffraction method described in JIS Z8825-1. The specific surface area of the filler can be measured by the BET method described in JIS Z8830.

The content of the filler is preferably 1 to 45% by mass relative to the photocurable resin composition. If the content of the filler is 1% by mass or more, the moisture resistance of a cured product of the photocurable resin composition is easily improved, and if it is 45% by mass or less, the coating stability of the photocurable resin composition is hardly impaired. The content of the filler is more preferably 10 to 30% by mass relative to the photocurable resin composition.

The photocurable resin composition of the present invention may further comprise, as required: coupling agents such as thermal radical polymerization initiators and silane coupling agents, ion capturing agents, ion exchangers, leveling agents, pigments, dyes, sensitizers, plasticizers, antifoaming agents, and the like.

Examples of the silane coupling agent include: vinyltrimethoxysilane, gamma- (meth) acryloyloxypropyltrimethoxysilane, gamma-glycidoxypropyltrimethoxysilane, gamma-glycidoxypropyltriethoxysilane, etc. The content of the silane coupling agent may be 0.01 to 5% by mass relative to the curable compound a. When the content of the silane coupling agent is 0.01% by mass or more, the cured product of the photocurable resin composition tends to have sufficient adhesiveness.

The photocurable resin composition of the present invention may further comprise a spacer or the like for adjusting the gap of the liquid crystal display panel.

The total content of the other components E is preferably 1 to 50% by mass relative to the photocurable resin composition. If the total content of the other components E is 50% by mass or less, the viscosity of the photocurable resin composition is less likely to increase excessively, and the coating stability is less likely to be impaired.

1-6 physical Properties of Photocurable resin composition

The viscosity of the photocurable resin composition of the present invention at 25 ℃ and 2.5rpm with an E-type viscometer is preferably 200 pas to 450 pas, more preferably 300 pas to 400 pas. If the viscosity is within the above range, the coating property of the photocurable resin composition by the dispenser becomes good.

The photocurable resin composition of the present invention is useful, for example, as a sealant. The sealant is preferably a display element sealant used for sealing a display element such as a liquid crystal display element, an organic EL element, or an LED element. The photocurable resin composition of the present invention can preferably suppress liquid crystal contamination, and therefore the sealant for a display element is particularly preferably a liquid crystal sealant, and more preferably a liquid crystal sealant for a liquid crystal dropping process.

Since the compound B contained in the photocurable resin composition of the present invention exhibits good light absorption even for light of a long wavelength, it can be cured in a short time while reducing damage to a liquid crystal layer caused by light. Further, since compound B contains many NHCO groups per 1 molecule, it has appropriate hydrophilicity and can highly suppress elution in a liquid crystal material.

2. Liquid crystal display panel and method for manufacturing the same

The display element panel of the present invention includes: the liquid crystal display device includes a pair of substrates, a display element disposed between the pair of substrates, and a sealing member sealing the display element. The sealing member may be a cured product of the display element sealing agent of the present invention. The display element sealant of the present invention comprises the photocurable resin composition of the present invention.

Examples of the display element include a liquid crystal display element, an organic EL element, an LED element, and the like. Among them, the photocurable resin composition of the present invention is preferably a liquid crystal display device in terms of being able to favorably suppress liquid crystal contamination.

That is, the liquid crystal display panel of the present invention includes: the liquid crystal display device includes a display substrate, a counter substrate paired with the display substrate, a frame-shaped sealing member arranged between the display substrate and the counter substrate, and a liquid crystal layer filled in a space surrounded by the sealing member between the display substrate and the counter substrate. The sealing member may be a cured product of the liquid crystal sealing agent of the present invention. The liquid crystal sealing agent of the present invention comprises the photocurable resin composition of the present invention.

The display substrate and the counter substrate are transparent substrates. The transparent substrate may be made of glass, or plastic such as polycarbonate, polyethylene terephthalate, polyether sulfone, or PMMA.

A matrix of TFTs, color filters, black matrices, and the like may be disposed on the surface of the display substrate or the counter substrate. An alignment film may be further disposed on the surface of the display substrate or the counter substrate. The alignment film contains a known organic alignment agent and an inorganic alignment agent.

The liquid crystal display panel is manufactured by using the liquid crystal sealing agent of the present invention. The liquid crystal display panel is manufactured by a liquid crystal dropping process and a liquid crystal injecting process.

The method for manufacturing the liquid crystal display panel by using the liquid crystal dropping process comprises the following steps:

1) forming a seal pattern of the liquid crystal sealing agent of the present invention on one substrate;

2) dropping a liquid crystal in a region of the substrate surrounded by the seal pattern or in a region of the other substrate opposed to the region surrounded by the seal pattern in a state where the seal pattern is not cured;

3) a step of overlapping one substrate with another substrate with a seal pattern interposed therebetween; and

4) and curing the seal pattern.

In the step 2), the uncured state of the seal pattern means a state in which the curing reaction of the liquid crystal sealing agent does not proceed to the gel point. Therefore, in the step 2), the seal pattern may be semi-cured by light irradiation or heating in order to suppress dissolution of the liquid crystal sealing agent in the liquid crystal. One substrate and the other substrate are respectively a display substrate or a counter substrate.

In the step 4), only curing by light irradiation may be performed, but curing by heating may be performed after curing by light irradiation. By performing curing by light irradiation, the liquid crystal sealing agent can be cured in a short time, and thus dissolution in the liquid crystal can be suppressed. By combining curing by light irradiation and curing by heating, damage to the liquid crystal layer due to light can be reduced as compared with the case of curing by light irradiation alone.

The light to be irradiated is preferably light having a wavelength of 370nm to 450 nm. This is because the liquid crystal material and the driving electrode are less damaged by the light of the above wavelength. For the light irradiation, a known light source that emits ultraviolet light or visible light can be used. When visible light is irradiated, a high-pressure mercury lamp, a low-pressure mercury lamp, a metal halide lamp, a xenon lamp, a fluorescent lamp, or the like can be used.

The irradiation energy may be energy of such a degree that the curable compound a can be cured. The photocuring time depends on the composition of the liquid crystal sealing agent, but is, for example, about 10 minutes.

The heat curing temperature depends on the composition of the liquid crystal sealing agent, but is, for example, 120 ℃ and the heat curing time is about 2 hours.

The liquid crystal sealant of the present invention has reduced dissolution in liquid crystal. Therefore, the liquid crystal display panel having the cured product of the liquid crystal sealing agent of the present invention can have high-quality display performance with less contamination by liquid crystal.

Examples

The present invention will be described in more detail below with reference to examples. The scope of the present invention is not to be interpreted as being limited by these examples.

1. Synthesis and evaluation of Compound B and comparative Compound

(1) Synthesis of

(Synthesis example 1)

3.16g of a hexamethylene diisocyanate biuret modified product (manufactured by Mitsui chemical Co., Ltd., Takenate D-165N, isocyanate equivalent: 179.5g/eq) and 40g of toluene were added to a four-necked flask equipped with a stirrer, a nitrogen inlet, a reflux condenser and a thermometer, and stirred at 80 ℃. Then, 2.50g (8.80X 10) of the solution was added^-3Mol) of 2- (2-hydroxyethylthio) -9, 10-anthraquinone in 100g of toluene, 1 drop by using dibutyltin as a catalyst, and then directly stirring at 80 ℃ for 1 hour under a nitrogen atmosphere.

After confirming the disappearance of 2- (2-hydroxyethylthio) -9, 10-anthraquinone by Thin Layer Chromatography (TLC), a solution prepared by dissolving 1.27g of 4-hydroxybutyl acrylate (manufactured by Tokyo chemical industry Co., Ltd.) in 5g of toluene was added dropwise thereto, and the mixture was stirred at 80 ℃ for 1 hour under atmospheric pressure. After the reaction was completed, the four-necked flask was left to cool at room temperature, and the precipitated crystal component was separated. The obtained crystal fraction was mixed with toluene again, stirred at 100 ℃ for 1 hour, and then cooled with ice again to remove impurity components. The recovered crystalline component was sufficiently dried in an oven to obtain compound B-1.

(Synthesis example 2)

0.5g (2.1X 10) of a solution was put into a four-necked flask equipped with a stirrer, a nitrogen inlet tube, a reflux condenser and a thermometer^-3Mol) of 2-hydroxymethylanthraquinone (manufactured by Takeka chemical Co., Ltd.) and 20g of toluene were stirred at 90 ℃ and 1 drop of dibutyltin was added as a catalyst. Then, 0.45g of hexamethylene was added dropwise thereto over 20 minutesA solution of a modified biuret isocyanate (manufactured by Mitsui chemical Co., Ltd., Takenate D-165N; isocyanate equivalent: 179.5g/eq) dissolved in 10g of toluene was stirred at 80 ℃ for 2 hours under a nitrogen atmosphere. After the reaction was completed, the four-necked flask was cooled in an ice bath, and the precipitated crystal component was separated. The obtained crystal fraction was mixed with toluene again, stirred at 90 ℃ for 1 hour, and then cooled with ice again to remove impurity components. The recovered crystalline component was sufficiently dried in an oven to obtain compound B-2.

(Synthesis example 3)

5.00g (1.76X 10 g) of a flask equipped with a stirrer, a nitrogen inlet tube, a reflux condenser and a thermometer was charged into the flask^-2Mol) of 2- (2-hydroxyethylthio) -9, 10-anthraquinone and 150g of toluene were stirred at 80 ℃ and 1 drop of dibutyltin was added as a catalyst. Subsequently, a solution prepared by dissolving 3.79g of a hexamethylene diisocyanate biuret modified product (manufactured by Mitsui chemical Co., Ltd., Takenate D-165N, isocyanate equivalent weight of 179.5g/eq) in 10g of toluene was added dropwise over 30 minutes. After completion of the dropwise addition, the mixture was stirred at 80 ℃ for 3 hours under a nitrogen atmosphere, and then 10.6g of isopropyl alcohol was added thereto and the mixture was directly stirred for 2 hours. After the reaction was completed, the four-necked flask was cooled in an ice bath, and the crystal component was separated. The obtained crystal fraction was mixed with toluene again, stirred at 100 ℃ for 1 hour, and then cooled with ice again to remove impurity components. The recovered crystalline component was sufficiently dried in an oven to obtain compound B-3.

(Synthesis example 4)

3.0g (1.06X 10) of a solution was placed in a four-necked flask equipped with a stirrer, nitrogen inlet tube, reflux condenser and thermometer^-2Mol) of 2- (2-hydroxyethylthio) -9, 10-anthraquinone and 100g of toluene were stirred at 110 ℃ and 1 drop of dibutyltin was added as a catalyst. Subsequently, a solution prepared by dissolving 2.95g of a hexamethylene diisocyanate biuret modified product (manufactured by Mitsui chemical Co., Ltd., Takenate D-165N, isocyanate equivalent weight of 179.5g/eq) in 10g of toluene was added dropwise over 30 minutes.

After confirming the disappearance of 2- (2-hydroxyethylthio) -9, 10-anthraquinone by Thin Layer Chromatography (TLC), a solution prepared by dissolving 1.43g of 1-octadecanol (manufactured by Tokyo chemical industry Co., Ltd.) in 10g of toluene was further added dropwise thereto, and the mixture was stirred at 110 ℃ for 2 hours under a nitrogen atmosphere. After the reaction was completed, the four-necked flask was cooled in an ice bath, and the precipitated crystal component was separated. The obtained crystal fraction was mixed with toluene again, stirred at 100 ℃ for 1 hour, and then cooled with ice again to remove impurity components. The crystalline component recovered by filtration was sufficiently dried in an oven to obtain compound B-4.

(Synthesis example 5)

5.0g (1.76X 10 g) of a solution was placed in a four-necked flask equipped with a stirrer, nitrogen inlet tube, reflux condenser and thermometer^-2Mol) of 2- (2-hydroxyethylthio) -9, 10-anthraquinone and 150g of toluene were stirred at 80 ℃ and 1 drop of dibutyltin was added as a catalyst. Subsequently, a solution prepared by dissolving 3.98g of an allophanate-modified hexamethylene diisocyanate (manufactured by Mitsui chemical Co., Ltd., Takenate D-178NL, isocyanate equivalent: 216.1g/eq) in 10g of toluene was added dropwise over 30 minutes, and then the mixture was stirred under nitrogen atmosphere at 80 ℃ for 2 hours. After the reaction was completed, the four-necked flask was cooled in an ice bath, and the precipitated crystal component was separated. The obtained crystal fraction was mixed with toluene again, stirred at 100 ℃ for 1 hour, and then cooled with ice again to remove impurity components. The recovered crystalline component was sufficiently dried in an oven to obtain compound B-5.

(Synthesis example 6)

1.0g (3.52X 10) of a solution was placed in a four-necked flask equipped with a stirrer, nitrogen inlet, reflux condenser and thermometer^-3Mol) of 2- (2-hydroxyethylthio) -9, 10-anthraquinone and 70g of ethyl acetate were stirred at 70 ℃ and 1 drop of dibutyltin was added as a catalyst. Subsequently, a solution prepared by dissolving 0.28g of hexamethylene diisocyanate (manufactured by Tokyo chemical industry Co., Ltd.) in 10g of ethyl acetate was added dropwise over 10 minutes, and then the mixture was stirred at 70 ℃ for 1 hour under a nitrogen atmosphere. After the reaction was completed, the four-necked flask was left to cool at room temperature, and the precipitated crystal component was separated. Mixing the obtained crystal with ethyl acetate again, stirring at 80 deg.C for 1 hr, and removing impurities by ice coolingAnd (4) dividing. The recovered crystalline component was sufficiently dried in an oven to obtain compound R-1.

(Synthesis example 7)

10.0g (3.52X 10 g) of a solution was placed in a four-necked flask equipped with a stirrer, nitrogen inlet, reflux condenser and thermometer^-2Mol) of 2- (2-hydroxyethylthio) -9, 10-anthraquinone and 150g of methyl isobutyl ketone were stirred at 80 ℃ and 1 drop of dibutyltin was added as a catalyst. Subsequently, a solution prepared by dissolving 5.53g of dicyclohexylmethane 4, 4' -diisocyanate (manufactured by Tokyo chemical industry Co., Ltd.) in 25g of methyl isobutyl ketone was added dropwise over 30 minutes, and then the mixture was stirred at 80 ℃ for 3 hours under a nitrogen atmosphere. After the reaction was completed, the four-necked flask was cooled in an ice bath, and the precipitated crystal component was separated. The obtained crystal component was mixed with methyl isobutyl ketone again, stirred at 100 ℃ for 1 hour, and then cooled with ice again to remove impurity components. The recovered crystalline component was sufficiently dried in an oven to obtain compound R-2.

(Synthesis example 8)

5.0g (1.76X 10 g) of a solution was placed in a four-necked flask equipped with a stirrer, nitrogen inlet tube, reflux condenser and thermometer^-2Mol) of 2- (2-hydroxyethylthio) -9, 10-anthraquinone and 150g of toluene were stirred at 80 ℃ and 1 drop of dibutyltin was added as a catalyst. Then, 5.25g (2.20X 10) of the resulting solution was added dropwise thereto over 30 minutes^-2Mol) of 1,1- (bisacryloyloxymethyl) ethyl isocyanate (manufactured by showa electrician, Karenz BEI) was dissolved in 10g of toluene, and then the solution was stirred under nitrogen atmosphere at 80 ℃ for 2 hours. After the reaction was completed, toluene was distilled off using an evaporator. To the residue were added 70g of toluene and 20g of ethyl acetate, and the mixture was uniformly dissolved and washed 10 times with 40g of ultrapure water. After washing with water, the solvent was distilled off again using an evaporator to obtain compound R-3.

(Synthesis example 9)

3.43g (1.21X 10 g) of a solution was placed in a four-necked flask equipped with a stirrer, nitrogen inlet, reflux condenser and thermometer^-2Moles) of 2- (2-hydroxyethylthio) -9, 10-anthraquinone and 12.15g of one-part polyurethane resin (Mitsui Chemicals)Manufactured by seikanate M-631N, NCO% ═ 4.58%, weight average molecular weight 17000, solvent: ethyl acetate/methyl ethyl ketone), and after stirring at 80 ℃, 30g of methyl ethyl ketone was further added to form a uniform solution. Subsequently, dibutyl tin dissolved in toluene was added dropwise as a catalyst, and the mixture was stirred at 80 ℃ for 2 hours under a nitrogen atmosphere. After the reaction was completed, the four-necked flask was cooled in an ice bath, and the precipitated crystal component was separated. The obtained crystal fraction was mixed with toluene again, stirred at 100 ℃ for 1 hour, and then cooled with ice again to remove impurity components. The recovered crystalline component was sufficiently dried in an oven to obtain compound R-4.

(Synthesis example 10)

5.6g (0.0225 mol) of 2-chlorothioxanthone and 2.6g (0.0225 mol) of the potassium salt of 2-mercaptoethanol were stirred in 20ml of N, N-dimethylacetamide at 100 ℃ for 18 hours. Next, the obtained reaction mixture was added to 2N hydrochloric acid, and extraction was performed with ethyl acetate. After customary work-up and chromatographic purification of the extract, 3.5g of 2- (2-hydroxyethylthio) -thioxanthen-9-one are obtained.

(Synthesis example 11)

5.00g (1.74X 10 g) of a flask equipped with a stirrer, a nitrogen inlet tube, a reflux condenser and a thermometer was charged into the flask^-2Mole) of 2- (2-hydroxyethylthio) -thioxanthen-9-one synthesized in Synthesis example 10 and 50g of toluene were stirred at 80 ℃ and 1 drop of dibutyltin was added as a catalyst. Subsequently, a solution prepared by dissolving 2.08g of a hexamethylene diisocyanate biuret modified product (manufactured by Mitsui chemical Co., Ltd., Takenate D-165N, isocyanate equivalent weight of 179.5g/eq) in 10g of toluene was added dropwise over 30 minutes, and the mixture was stirred at 80 ℃ for 3 hours under a nitrogen atmosphere.

After confirming the disappearance of 2- (2-hydroxyethylthio) -thioxanthen-9-one by Thin Layer Chromatography (TLC), a solution prepared by dissolving 0.84g of 4-hydroxybutyl acrylate (manufactured by Tokyo chemical industry Co., Ltd.) in 5g of toluene was added dropwise thereto, and the mixture was stirred at 80 ℃ for 1 hour under atmospheric pressure. After the reaction was completed, the four-necked flask was left to cool at room temperature, and the precipitated solid was separated. The recovered solid component was sufficiently dried in an oven to obtain compound B-6.

(Synthesis example 12)

5.00g (1.74X 10 g) of a flask equipped with a stirrer, a nitrogen inlet tube, a reflux condenser and a thermometer was charged into the flask^-2Mole) of 2- (2-hydroxyethylthio) -thioxanthen-9-one synthesized in Synthesis example 10 and 50g of toluene were stirred at 80 ℃ and 1 drop of dibutyltin was added as a catalyst. Subsequently, a solution prepared by dissolving 3.74g of a hexamethylene diisocyanate biuret modified product (manufactured by Mitsui chemical Co., Ltd., Takenate D-165N, isocyanate equivalent weight of 179.5g/eq) in 10g of toluene was added dropwise over 30 minutes. After completion of the dropwise addition, the mixture was stirred at 80 ℃ for 3 hours under a nitrogen atmosphere, and then 1.04g of isopropyl alcohol was added thereto and the mixture was directly stirred for 2 hours. After the reaction was completed, the four-necked flask was left to cool at room temperature, and the solid content was separated. The recovered solid component was sufficiently dried in an oven to obtain compound B-7.

(Synthesis example 13)

After confirming the disappearance of 2- (2-hydroxyethylthio) -thioxanthen-9-one by Thin Layer Chromatography (TLC), a solution prepared by dissolving 1.57g of 1-octadecanol (manufactured by Tokyo chemical industry Co., Ltd.) in 5g of toluene was further added dropwise thereto, and the mixture was stirred at 80 ℃ for 1 hour under atmospheric pressure. After the reaction was completed, the four-necked flask was left to cool at room temperature, and the precipitated solid was separated. The recovered solid component was sufficiently dried in an oven to obtain compound B-8.

(Synthesis example 14)

Comprises a stirrer, a nitrogen gas inlet pipe, a reflux cooling pipe,In a four-necked flask with a thermometer, 5.00g (1.74X 10) of a solution was charged^-2Mole) of 2- (2-hydroxyethylthio) -thioxanthen-9-one synthesized in Synthesis example 10 and 50g of toluene were stirred at 80 ℃ and 1 drop of dibutyltin was added as a catalyst. Subsequently, a solution prepared by dissolving 4.51g of an allophanate-modified hexamethylene diisocyanate (manufactured by Mitsui chemical Co., Ltd., Takenate D-178NL, isocyanate equivalent: 216.1g/eq) in 10g of toluene was added dropwise over 30 minutes, and the mixture was stirred at 80 ℃ for 3 hours under a nitrogen atmosphere. After the reaction was completed, the four-necked flask was left to cool at room temperature, and the solid content was separated. The recovered solid component was sufficiently dried in an oven to obtain compound B-9.

(Synthesis example 15)

5.00g (1.74X 10 g) of a flask equipped with a stirrer, a nitrogen inlet tube, a reflux condenser and a thermometer was charged into the flask^-2Mole) of 2- (2-hydroxyethylthio) -thioxanthen-9-one synthesized in Synthesis example 10 and 50g of ethyl acetate were stirred at 80 ℃ and 1 drop of dibutyltin was added as a catalyst. Subsequently, a solution prepared by dissolving 1.46g of hexamethylene diisocyanate (manufactured by Tokyo chemical industry Co., Ltd.) in 10g of ethyl acetate was added dropwise over 10 minutes, and then the mixture was stirred at 70 ℃ for 1 hour under a nitrogen atmosphere. After the reaction was completed, the four-necked flask was left to cool at room temperature, and the precipitated solid was separated. The recovered solid component was sufficiently dried in an oven to obtain compound R-5.

(Synthesis example 16)

5.00g (1.74X 10 g) of a flask equipped with a stirrer, a nitrogen inlet tube, a reflux condenser and a thermometer was charged into the flask^-2Moles) of 2- (2-hydroxyethylthio) -thioxanthen-9-one synthesized in Synthesis example 10 and 50g of methyl isobutyl ketone were stirred at 80 ℃ and 1 drop of dibutyltin was added as a catalyst. Subsequently, a solution prepared by dissolving 2.28g of dicyclohexylmethane 4, 4' -diisocyanate (manufactured by Tokyo chemical industry Co., Ltd.) in 25g of methyl isobutyl ketone was added dropwise over 30 minutes, and then the mixture was stirred at 80 ℃ for 3 hours under a nitrogen atmosphere. After the reaction was completed, the four-necked flask was left to cool at room temperature, and the precipitated solid was separated. Recovering the solid component inAnd fully drying in an oven to obtain the compound R-6.

(Synthesis example 17)

5.00g (1.74X 10 g) of a flask equipped with a stirrer, a nitrogen inlet tube, a reflux condenser and a thermometer was charged into the flask^-2Moles) of 2- (2-hydroxyethylthio) -thioxanthen-9-one synthesized in Synthesis example 10 and 50g of methyl isobutyl ketone were stirred at 80 ℃ and 1 drop of dibutyltin was added as a catalyst. Subsequently, 4.58g (1.91X 10) of the resulting solution was added dropwise thereto over 30 minutes^-2Mol) of 1,1- (bisacryloyloxymethyl) ethyl isocyanate (manufactured by showa electrician, Karenz BEI) was dissolved in 10g of toluene, and then the solution was stirred under nitrogen atmosphere at 80 ℃ for 2 hours. After the reaction was completed, toluene was distilled off using an evaporator. To the residue were added 70g of toluene and 20g of ethyl acetate, and the mixture was uniformly dissolved and washed 10 times with 40g of ultrapure water. After washing with water, the solvent was distilled off again using an evaporator to obtain compound R-7.

Table 1 shows the constituent materials used in synthesis examples 1 to 5, table 2 shows the constituent materials used in synthesis examples 6 to 9, table 3 shows the constituent materials used in synthesis examples 11 to 14, and table 4 shows the constituent materials used in synthesis examples 10 and 15 to 17.

[ Table 1]

[ Table 2]

[ Table 3]

[ Table 4]

(2) Evaluation of

(Experimental examples 1 to 9, comparative Experimental examples 1 to 10)

The molecular weights, the voltage holding ratios of the liquid crystals, and the N-I point drops of the liquid crystals of the compounds B-1 to B-9 obtained in synthesis examples 1 to 5 and 11 to 14, the compounds R-1 to R-7, 2- (2-hydroxyethylthio) -9, 10-anthraquinone, 2-hydroxymethyl-9, 10-anthraquinone (HMAQ), and the 2- (2-hydroxyethylthio) -thioxanthen-9-one obtained in synthesis examples 6 to 9 and 15 to 17 were evaluated by the following methods.

(molecular weight)

1) High Performance Liquid Chromatography (HPLC) assay

The above-mentioned compounds were prepared as sample solutions each dissolved in Tetrahydrofuran (THF), and subjected to High Performance Liquid Chromatography (HPLC) measurement under the following measurement conditions.

(conditions for HPLC measurement)

Column: acquity UPLC BEH C18, 2.1mmID × 100mm, particle size: 1.7 μm

Mobile phase: a: acetonitrile

B: 5mM ammonium acetate in water

A/B60/40 (0 min. 4 min.)

95/5 (4-9 minutes)

95/5 (9-10 minutes)

Flow rate: 0.4 mL/min

Among all the peaks detected at a detection wavelength of 400nm, the peak having the highest intensity (peak having the highest peak height) was defined as the "main peak" and the presence or absence of the main peak was confirmed. As a result, main peaks were detected for the compounds B-1 to B-9, the compounds R-1 to R-3, the compounds R-5 to R-7, 2- (2-hydroxyethylthio) -9, 10-anthraquinone, 2-hydroxymethyl-9, 10-anthraquinone (HMAQ) and 2- (2-hydroxyethylthio) -thioxanthen-9-one. On the other hand, for compound R-4, no major peak was detected.

2) Liquid chromatography mass spectrometry (LC/MS) assay

For the compounds in which the main peak was detected, the relative molecular mass corresponding to the peak top of the detected main peak was determined by liquid chromatography mass spectrometry (LC/MS).

(LC/MS measurement conditions)

Column: acquity UPLC BEH C18, 2.1mmID × 100mm, particle size: 1.7 μm

Mobile phase: a: acetonitrile

B: 5mM ammonium acetate in water

A/B60/40 (0 min. 4 min.)

95/5 (4-9 minutes)

95/5 (9-10 minutes)

Flow rate: 0.4 mL/min

Ionization: ESI (electrospray ionization), Positive/negative ion measurement

(Voltage holding ratio of liquid Crystal)

0.1g of the above compound and 1g of a liquid crystal (MLC-7021-000, manufactured by Merck) were put in a vial (virtual bottle) and heated at 120 ℃ for 1 hour to obtain a liquid crystal mixture. Subsequently, the liquid crystal mixture was taken out, injected into a glass cell (KSSZ-10/B111M1NSS05, manufactured by EHC) on which a transparent electrode was formed in advance, applied with a voltage of 1V, and the voltage holding ratio at 60Hz was measured by a 6254 type measuring apparatus (manufactured by Toyoyang Technica).

The voltage holding ratio was ◎ when the voltage holding ratio was 95% or more, ○ when the voltage holding ratio was 90% or more and less than 95%, and x when the voltage holding ratio was less than 90%.

The higher the voltage holding ratio, the more the contamination of the liquid crystal is suppressed.

(N-I point drop of liquid Crystal)

0.1g of the above compound and 1g of a liquid crystal (MLC-7021-000 manufactured by Merck) were put in a vial, and heated at 120 ℃ for 1 hour to obtain a liquid crystal mixture. Then, 10mg of the liquid crystal mixture was put in an open aluminum pan (manufactured by Epolead Service Co., Ltd.), and the N-I point was measured by using a DTA-TG device (manufactured by Seiko instruments Co., Ltd.). The liquid crystal mixture was heated from 55 ℃ to 150 ℃ at a temperature rise rate of 2 ℃/min.

The amount of change in the N-I point with respect to the liquid crystal was ◎ when it was less than 2 ℃, ○ when it was 2 ℃ or more and less than 5 ℃, and x when it was 5 ℃ or more.

The measurement results of experimental examples 1 to 9 are shown in table 5, and the measurement results of comparative experimental examples 1 to 10 are shown in table 6. The "molecular weight" in tables 5 and 6 is the "weight average molecular weight" of compound R-4, since no main peak was detected in HPLC measurement. Since the other compounds detected a main peak in the HPLC measurement, "relative molecular mass" (molecular weight measured by LC/MS) corresponding to the peak of the main peak.

[ Table 5]

[ Table 6]

As shown in tables 5 and 6, it can be seen that: the compounds B-1 to B-5 of examples 1 to 5 having an NHCO group equivalent of 350g/eq showed higher liquid crystal voltage retention and less drop in the N-I point than the compounds R-1 to R-4 of examples 1 to 4 having an NHCO group equivalent of more than 350g/eq, the 2- (2-hydroxyethylthio) -9, 10-anthraquinone of example 5 not containing an NHCO group in the molecule, and the 2-hydroxymethyl-9, 10-anthraquinone (HMAQ) of example 6.

It is also known that: the N-I points of the compounds B-6 to B-9 of examples 6 to 9 in which the NHCO group equivalent was 350g/eq or less were less reduced than those of the compounds R-5 to R-7 of examples 7 to 9 in which the NHCO group equivalent exceeded 350 g/eq.

2. Preparation and evaluation of Photocurable resin composition

(curable Compound A)

Curable compound a-1:

methacrylic acid-modified bisphenol F type epoxy resin (95% partially methacrylate) was synthesized by the following method.

160g of a liquid bisphenol F-type epoxy resin (Epotohto YDF-8170C, made by Nisshinoki chemical Co., Ltd., epoxy equivalent of 160g/eq), 0.1g of p-methoxyphenol as a polymerization inhibitor, 0.2g of triethanolamine as a catalyst, and 81.7g of methacrylic acid were charged into a flask, and the reaction was carried out for 5 hours while introducing dry air and carrying out reflux stirring at 90 ℃. The obtained compound was washed 20 times with ultrapure water to obtain a methacrylic acid-modified bisphenol F type epoxy resin (curable resin a-1).

Light Acrylate 14EG-A, chemical Co., Ltd:

polyethylene glycol diacrylate represented by the following formula (molecular weight 600)

[ solution 8]

(Compound B)

Compounds B-1 to B-9 obtained in Synthesis examples 1 to 5 and 11 to 14

(Compound for comparison)

Compounds R-1 to R-7 obtained in Synthesis examples 6 to 9 and 15 to 17

2- (2-hydroxyethylthio) -9, 10-anthraquinones

2-hydroxymethyl-9, 10-anthraquinone (HMAQ)

Synthesis of 2- (2-hydroxyethylthio) -thioxanthen-9-one obtained in example 10

(thermosetting Compound C)

JeR resin 1004 (bisphenol A epoxy resin having an epoxy equivalent of 875g/eq to 975g/eq, a molecular weight of 1650 and a softening point of 97 ℃ C.) manufactured by Mitsubishi chemical corporation

(Heat curing agent D)

ADH (adipic acid dihydrazide, melting point 177 ℃ -184 ℃ C.) manufactured by Nippon chemical Co., Ltd

(other component E)

Silica particles S-100 (manufactured by Japan catalyst Ltd.)

Fine Polymer F351 (thermoplastic resin particles, manufactured by Ikko industries Co., Ltd., softening point of 120 ℃ C., average particle diameter of 0.3 μm)

KBM-403 (gamma-glycidoxypropyltrimethoxysilane, silane coupling agent) manufactured by shin Etsu chemical industries

(example 1)

430 parts by mass of the above-described synthesized curable compound A-1 as curable compound A, 200 parts by mass of Light Acrylate 14EG-A manufactured by Kyoeisha chemical Co., Ltd, 10 parts by mass of compound B-1 obtained in Synthesis example 1 as compound B, 50 parts by mass of JeR resin 1004 manufactured by Mitsubishi chemical company as thermosetting compound C, and 90 parts by mass of ADH manufactured by Japan chemical Co., Ltd were mixed using a three-roll mill to obtain a uniform solution, and 130 parts by mass of silica particles S-100 produced by Kagaku Kogyo Co., Ltd, 70 parts by mass of a fine particle polymer F351 produced by Ackko Co., Ltd, and 20 parts by mass of a silane coupling agent KBM-403 produced by shin-Etsu chemical industries, as the other component E, were sufficiently mixed to obtain a photocurable resin composition.

(examples 2 to 9 and comparative examples 1 to 10)

A photocurable resin composition was obtained in the same manner as in example 1, except that the composition shown in table 7 or table 8 was changed.

The obtained photocurable resin composition was evaluated for display characteristics by the following method.

(test of display characteristics of liquid Crystal display Panel)

Using a dispenser (Shotmaster, manufactured by high tech, Wucang, Ltd.), a 40mm × 45mm glass plate on which a transparent electrode and an alignment film were formed in advance was usedThe obtained photocurable resin composition was formed into a rectangular seal pattern (cross-sectional area 3500 μm) of 35mm × 40mm on a glass substrate (RT-DM88-PIN, manufactured by EHC)²) The seal pattern is a seal pattern having a rectangular shape of 38mm × 43mm and formed on the outer periphery thereof.

Next, a liquid crystal material (MLC-7021-. Next, the pair of glass substrates were bonded under reduced pressure, and then bonded by opening the atmosphere. Next, the two bonded glass substrates were held in a light-shielding box for 3 minutes, and then irradiated with 3000mJ/cm of light while the main seal was shielded by a 36mm × 41mm rectangular black matrix-coated substrate²The main seal is cured by heating the light containing visible light (light having a wavelength of 370nm to 450 nm) at 120 ℃ for 1 hour. Then, polarizing films were attached to both surfaces of the obtained liquid crystal cell to obtain a liquid crystal display panel.

The liquid crystal was aligned to the main seal edge of the obtained liquid crystal display panel and no color unevenness was observed at ○, △ was observed when color unevenness occurred in the vicinity of the main seal edge over a range of less than 1mm, and x was observed when color unevenness occurred in the vicinity of the main seal edge over a range of 1mm or more.

(test of display characteristics when liquid Crystal display Panel was energized)

In this case, ○ represents that the liquid crystal display function was sufficiently exhibited without white unevenness near the main seal, △ represents that white unevenness occurred in the vicinity of the main seal over a range of less than 1mm, △ represents that white unevenness occurred in the vicinity of the main seal over a range of 1mm or more and abnormal driving was not performed, and x represents that the liquid crystal display panel was not normally driven.

The evaluation results of examples 1 to 9 are shown in table 7; the evaluation results of comparative examples 1 to 10 are shown in table 8.

[ Table 7]

[ Table 8]

As shown in tables 7 and 8, it can be seen that: the photocurable resin compositions of examples 1 to 9 containing the compound B having a NHCO group equivalent of 350g/eq or less exhibited good display characteristics both when energized and when de-energized.

In contrast, it is known that: the photocurable resin compositions of comparative examples 1 to 4 and comparative examples 7 to 9, which contain a compound for comparison having an NHCO group equivalent of more than 350g/eq, and the photocurable resin compositions of comparative examples 5, 6 and 10, which do not contain an NHCO group, all exhibited poor display characteristics. This is considered to be because: since the comparative compound has little or no hydrophilic NHCO group, contamination of the liquid crystal cannot be sufficiently suppressed.

The present application claims priority based on Japanese patent application 2015-131160, filed on 30/6/2015, and Japanese patent application 2016-013332, filed on 27/1/2016. The contents described in the specification of this application are all incorporated in the specification of this application.

Industrial applicability

The present invention can provide a photocurable resin composition which has high curability against visible light and can highly suppress contamination of liquid crystal when used as, for example, a display element sealant, particularly a liquid crystal sealant.

Claims

1. A photocurable resin composition comprising:

a curable compound A having an ethylenically unsaturated double bond in the molecule; and

a compound B having an anthraquinone skeleton or a thioxanthone skeleton and 3 or more NHCO groups in a molecule, wherein the NHCO group equivalent represented by the formula (I) is 350g/eq or less;

2. The photocurable resin composition according to claim 1, wherein the compound B has a biuret skeleton or an allophanate skeleton in a molecule.

3. The photocurable resin composition according to claim 1, wherein the compound B is represented by the following formula (4) or formula (5),

in the formulae (4) and (5),

L₁each independently represents a single bond, an alkylene group having 1 to 10 carbon atoms, an alkyleneoxy group having 1 to 10 carbon atoms, an alkylenethio group having 1 to 10 carbon atoms, an arylene group having 6 to 10 carbon atoms, an aryleneoxy group having 6 to 10 carbon atoms or an arylenethio group having 6 to 10 carbon atoms,

x represents an organic group derived from a compound having at least p isocyanate groups in the molecule,

p represents an integer of 3 to 5.

4. The photocurable resin composition according to claim 1, wherein the compound B further has an ethylenically unsaturated double bond in the molecule, and

the curable compound A has no anthraquinone skeleton or thioxanthone skeleton.

5. The photocurable resin composition according to claim 1, wherein the content of the compound B is 0.01 to 10% by mass relative to the curable compound a.

6. The photocurable resin composition according to claim 1, wherein the curable compound a further has an epoxy group in a molecule.

7. The photocurable resin composition according to claim 1, further comprising a thermosetting compound C having an epoxy group in the molecule and a thermosetting agent D, and

the thermosetting compound C is different from the curable compound a.

8. The photocurable resin composition according to claim 7, wherein the thermal curing agent D is at least one selected from the group consisting of a dihydrazide-based thermal latent curing agent, an imidazole-based thermal latent curing agent, an amine adduct-based thermal latent curing agent, and a polyamine-based thermal latent curing agent.

9. A display element sealant comprising the photocurable resin composition according to claim 1.

10. A liquid crystal sealing agent comprising the photocurable resin composition according to claim 1.

11. The liquid crystal sealant according to claim 10, which is a liquid crystal sealant for a liquid crystal dropping process.

12. A method for manufacturing a liquid crystal display panel includes the steps of:

a step of forming a seal pattern on one substrate by using the liquid crystal sealant according to claim 10;

dropping a liquid crystal in a region of the seal pattern or on another substrate paired with the one substrate in a state where the seal pattern is not cured;

a step of overlapping the one substrate and the other substrate with the seal pattern interposed therebetween; and

and curing the seal pattern.

13. The method of manufacturing a liquid crystal display panel according to claim 12, wherein the step of curing the seal pattern includes a step of curing the seal pattern by irradiating light to the seal pattern.

14. The method of manufacturing a liquid crystal display panel according to claim 13, wherein the light irradiated to the seal pattern includes light in a visible light region.

15. The method of manufacturing a liquid crystal display panel according to claim 13, wherein the step of curing the seal pattern further comprises a step of curing the seal pattern by heating the seal pattern irradiated with light.

16. A liquid crystal display panel, comprising:

a pair of substrates, wherein the substrates are arranged in a row,

a frame-shaped sealing member disposed between the pair of substrates, and

a liquid crystal layer filled in a space surrounded by the sealing member between the pair of substrates;

the sealing member is a cured product of the liquid crystal sealing agent according to claim 10.