JP2008116488A - Photosensitive resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photosensitive resin composition for photospacers having good alkali developability and forming a cured product having excellent flexibility and elastic recovery characteristics. <P>SOLUTION: The alkali developable photosensitive resin composition (Q) for photospacers comprises a hydrophilic polymer (A), a polyfunctional (meth) acrylate monomer (B), a polysiloxane (C) having two or more hydrolyzable alkoxy groups and a photo-radical polymerization initiator (D), wherein the polysiloxane (C) is a condensate comprising a silane compound (c1) represented by a general formula (1) as an essential constituent monomer. R<SP>1</SP>is one or more organic groups selected from the group consisting of a (meth) acryloyloxyalkyl group, a glycidoxyalkyl group, a mercaptoalkyl group and an aminoalkyl group, each of which has a 1-6C alkyl group; R<SP>2</SP>is a 1-12C aliphatic saturated hydrocarbon group or a 6-12C aromatic hydrocarbon group; R<SP>3</SP>is a 1-4C alkyl group; and m is 0 or 1. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a photosensitive resin composition for a photospacer that is cured by a process including light irradiation and is capable of alkali development, and a photospacer provided for maintaining a gap in a liquid crystal cell formed using the composition. It is.

  In recent years, liquid crystal display devices have attracted attention, and photosensitive resins are frequently used in the manufacturing process. For example, the portion corresponding to the pixel on the color filter is a color pigment dispersion resist, and the resist is also used for the black matrix. As a resist used for such a portion, a so-called negative resist is often used in which only a portion irradiated with light is hardened when exposed through a mask and an unexposed portion is peeled off by development.

  Now, in the liquid crystal display device technology, in order to maintain the thickness of the liquid crystal layer between both the color filter side substrate and the thin film transistor (TFT) side substrate, glass or resin transparent spherical particles (beads) called spacers are used. Sprayed inside the cell. Since these spacers are transparent particles, if there is a liquid crystal and a spacer in the pixel, light leaks through the spacer particles during black display, and both substrates in which the liquid crystal is sealed The presence of the spacer particles between them disturbs the orientation of the liquid crystal molecules in the vicinity of the spacer particles, causing light leakage at this portion, resulting in a decrease in the contrast of the liquid crystal display device and adversely affecting the display quality. Yes. Also, for example, in a liquid crystal display device in which the distance between the two substrates (the thickness of the liquid crystal layer) is narrow, such as a ferroelectric liquid crystal, the distance between the two substrates can be maintained uniformly and accurately using this spacer particle. It is difficult.

  For this, for example, a photosensitive resin is used, and a columnar resin is formed on a black matrix in a lattice pattern located between pixels at a desired position by a photolithography method such as partial pattern exposure and development. There has been proposed a method of forming a spacer. Such a spacer is hereinafter referred to as a photo spacer. Since the photo spacer can be formed at a position avoiding the pixels, it does not adversely affect the display quality as described above, and the display quality can be improved.

  On the other hand, in recent years, as the mother glass for LCD (Liquid Crystal Display) production becomes larger, a dripping method (ODF method) (ODF: One Drop Fill) has been proposed instead of the conventional liquid crystal inflow method (vacuum suction method). ing. In the ODF method, after a predetermined amount of liquid crystal is dropped, the liquid crystal is injected by being sandwiched between substrates, so that the number of processes and the process time can be reduced as compared with the conventional vacuum suction method. However, in the ODF method, a predetermined amount of liquid crystal calculated from the cell gap is dropped and held, so that the flexibility of correcting the height variation and the subtle pressure applied in the plane are applied. It is desirable for photo spacers to have elastic properties that do not affect the difference.

That is, a photo spacer having a high total deformation amount and a high elastic recovery rate is required. Photo spacers that do not have such characteristics may cause bubbles in the liquid crystal when the panel is produced, and the cell gap is not uniform, and the display quality of the liquid crystal display device deteriorates. For example, color unevenness is noticeable. Inconveniences, such as becoming something, occur. As a proposal for solving these problems, for example, a photosensitive resin composition for photospacers having an alkali developability (Patent Document 1) has been proposed. This proposal proposes a photospacer with excellent mechanical strength by using a photopolymerizable monomer, a photopolymerization initiator, and an epoxy resin having alkali developability and reactivity in combination. However, in a composition in which such an epoxy resin and a carboxylic acid component necessary for alkali development coexist, a crosslinking reaction proceeds between the epoxy group and the carboxylic acid. As a result, there has been a problem that the elastic recovery characteristic becomes worse due to brittleness.
In recent years, a further new proposal (Patent Document 2) has been made as a material for forming a photospacer having such a characteristic as to solve such a problem. In this proposal, the amount of polyfunctional monomer in the total solid content is improved by 50 to 70%. However, when a large amount of polyfunctional monomer is used, there is a problem that alkali developability deteriorates.
JP 2001-226449 A JP 2002-174812 A

  The present invention has been made in order to solve the above problems, and is a photosensitive resin composition having good alkali developability, and the cured product has excellent flexibility and excellent elastic recovery characteristics. It is another object of the present invention to provide a photo spacer having excellent flexibility and excellent elastic recovery characteristics.

The inventors of the present invention have arrived at the present invention as a result of intensive studies to solve the above problems.
That is, the present invention comprises a hydrophilic polymer (A), a polyfunctional (meth) acrylate monomer (B), a polysiloxane (C) having two or more hydrolyzable alkoxy groups, and a radical photopolymerization initiator (D). A photosensitive resin composition for a photospacer that can be developed with an alkali, wherein the polysiloxane (C) is a condensate containing, as an essential constituent monomer, a silane compound (c1) represented by the following general formula (1): (Q); and a photo spacer provided for maintaining a gap in a liquid crystal cell formed by curing the same by a process including light irradiation.

In the formula, R ¹ is one or more selected from the group consisting of a (meth) acryloyloxyalkyl group, a glycidoxyalkyl group, a mercaptoalkyl group, and an aminoalkyl group having 1 to 6 carbon atoms in the alkyl group. R ² is an aliphatic saturated hydrocarbon group having 1 to 12 carbon atoms or an aromatic hydrocarbon group having 6 to 12 carbon atoms, R ³ is an alkyl group having 1 to 4 carbon atoms, and m is 0 or 1. is there.

The photosensitive resin composition of the present invention and the photospacer obtained therefrom have the following effects.
-The photosensitive resin composition is excellent in alkali developability.
-Photo spacers have excellent flexibility and elastic recovery characteristics.

The photosensitive resin composition of the present invention comprises a hydrophilic polymer (A) [hereinafter sometimes referred to simply as (A)], a polyfunctional (meth) acrylate monomer (B) [hereinafter referred to simply as (B). A polysiloxane (C) having two or more hydrolyzable alkoxy groups [hereinafter, it may be simply referred to as polysiloxane (C) or simply (C)], and light. It contains a radical polymerization initiator (D) [hereinafter sometimes simply referred to as (D)], and (C) is a specific polysiloxane, so that it has excellent alkali developability and is flexible and elastic. A photo spacer having excellent recovery characteristics is provided.
In the above and the following, for example, the expression with (meth) such as “(meth) acrylate” means “acrylate and / or methacrylate”.

  Below, (A)-(D) which is an essential structural component of the photosensitive resin composition of this invention is demonstrated in order.

The hydrophilicity index in the hydrophilic polymer (A) in the present invention is defined by HLB. Generally, the larger this value, the higher the hydrophilicity.
Although the preferable range of the HLB value of (A) varies depending on the resin skeleton of (A) (for example, vinyl resin, epoxy resin, polyester resin, etc.), it is preferably 4 to 19, more preferably 5 to 18. Especially preferably, it is 6-17. When it is 4 or more, the developing property is further improved when developing the photo spacer, and when it is 19 or less, the water resistance of the cured product is further improved. In addition, HLB in this invention is an HLB value by the Oda method, is a hydrophilicity-hydrophobicity balance value, and can be calculated from the ratio of the organic value and inorganic value of an organic compound.
HLB≈10 × Inorganic / Organic In addition, the inorganic value and the organic value are described in the document “Surfactant Synthesis and Applications” (published by Tsuji Shoten, Oda, Teramura), page 501; It is described in detail on page 198 of “Introduction to New Surfactants” (Takehiko Fujimoto, published by Sanyo Chemical Industries, Ltd.).

  Moreover, the solubility parameter (hereinafter referred to as SP value) of (A) is preferably 7 to 14, more preferably 8 to 13, and particularly preferably 11 to 13. When it is 7 or more, the developability can be further improved, and when it is 14 or less, the water resistance of the cured product is further improved.

The SP value in the present invention is calculated by the method described in the following document proposed by Fedors et al.
"POLYMER ENGINEERING AND SCIENCE, FEBRUARY, 1974, Vol. 14, No. 2, ROBERT F. FEDORS. (Pp. 147-154)"
Those with close SP values are easy to mix with each other (highly dispersible), and those with a distant numerical value are indexes indicating that they are difficult to mix.

(A) preferably has a carboxyl group from the viewpoint of developability. The carboxyl group content is indicated by an acid value.
The acid value of (A) is preferably 10 to 500 mgKOH / g. If it is 10 mgKOH / g or more, the developability is more likely to be exhibited, and if it is 500 mgKOH / g or less, the water resistance of the cured product can be further improved.

The acid value in the present invention can be measured by an indicator titration method using an alkaline titration solution.
The method is as follows.
(I) About 1 g of a sample is precisely weighed and placed in an Erlenmeyer flask, and then a neutral methanol / acetone solution (a mixture of acetone and methanol at 1: 1 (volume ratio)) is added and dissolved.
(Ii) Add several drops of phenolphthalein indicator and titrate with 0.1 mol / L potassium hydroxide titration solution. The end point of neutralization is defined as the time when the indicator is slightly red for 30 seconds.
(Iii) Determine using the following equation.
Acid value (KOHmg / g) = (A × f × 5.61) / S
However, A: The number of mL of 0.1 mol / L potassium hydroxide titration solution.
f: Potency of 0.1 mol / L potassium hydroxide titration solution
S: Sampling amount (g)

Examples of (A) include a hydrophilic vinyl polymer (A1) (hereinafter sometimes simply referred to as (A1)) and a hydrophilic epoxy polymer (A2) (hereinafter simply referred to as (A2)). ), Hydrophilic polyester resin (A3), hydrophilic polyamide resin (A4), hydrophilic polycarbonate resin (A5), and hydrophilic polyurethane resin (A6). (A) may be used by 1 type and may use 2 or more types together.
Among these, (A1) and (A2) are preferable from the viewpoint of photocuring reactivity of the photosensitive resin composition and the viewpoint of ease of production.

  Examples of (A1) include those having a hydrophilic group in the side chain and / or terminal of the vinyl polymer molecule. Examples of the hydrophilic group include a carboxyl group, a hydroxyl group, a sulfonic acid group, an amino group, an amide group, a polyether group, and a combination of two or more of these. In order to exhibit sufficient developability, those having a hydrophilic group, particularly a carboxyl group in the side chain are preferred.

  A preferred production method of (A1) is a vinyl monomer having a hydrophilic group (a) (hereinafter sometimes simply referred to as (a)) and, if necessary, a hydrophobic group-containing vinyl monomer (b) (hereinafter simply referred to as (b) ) Is sometimes vinyl-polymerized.

Examples of the vinyl monomer (a) having a hydrophilic group include the following vinyl monomers (a1) to (a7).
(A1) Carboxyl group-containing vinyl monomer:
Unsaturated monocarboxylic acids [such as (meth) acrylic acid, crotonic acid and cinnamic acid], unsaturated polyvalent (2-4 valent) carboxylic acids [such as (anhydrous) maleic acid, itaconic acid, fumaric acid and citraconic acid], Unsaturated polyvalent carboxylic acid alkyl (alkyl group having 1 to 10 carbon atoms) ester [maleic acid monoalkyl ester, fumaric acid monoalkyl ester, citraconic acid monoalkyl ester, etc.] and salts thereof [alkali metal salt (sodium salt) And potassium salts, etc.), alkaline earth metal salts (calcium salts and magnesium salts, etc.), amine salts and ammonium salts, etc.].
Of (a1), preferred is an unsaturated monocarboxylic acid from the viewpoint of hydrophilicity, and more preferred is (meth) acrylic acid.

(A2) Hydroxyl group-containing vinyl monomer:
Hydroxyalkyl (meth) acrylate [2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, etc.], polyalkylene glycol mono (meth) acrylate [polyethylene glycol mono (meta ) Acrylate etc.], alkylol (meth) acrylamide [N-methylol (meth) acrylamide etc.], hydroxystyrene and 2-hydroxyethylpropenyl ether.
Among (a2), hydroxyalkyl (meth) acrylate, particularly 2-hydroxyethyl (meth) acrylate is preferable from the viewpoint of alkali developability.
(A3) Sulphonic acid group-containing vinyl monomer:
Examples thereof include vinyl sulfonic acid, (meth) allyl sulfonic acid, styrene sulfonic acid, α-methyl styrene sulfonic acid, 2- (meth) acryloylamido-2-methylpropane sulfonic acid, and salts thereof. Examples of the salt include alkali metal (sodium and potassium) salts, alkaline earth metal (calcium and magnesium) salts, primary to tertiary amine salts, ammonium salts and quaternary ammonium salts.

(A4) Amino group-containing vinyl monomer:
Tertiary amino group-containing (meth) acrylates [dialkylaminoalkyl (meth) acrylates such as dimethylaminoethyl (meth) acrylate and diethylaminoethyl (meth) acrylate)] and the like.
(A5) Amide group-containing vinyl monomer:
(Meth) acrylamide, N-alkyl (C1-6) (meth) acrylamide, diacetone acrylamide, N, N'-methylene-bis (meth) acrylamide, N, N-dialkyl (C1-6) or Diaralkyl (7 to 15 carbon atoms) (meth) acrylamide (for example, N, N-dimethylacrylamide and N, N-dibenzylacrylamide), methacrylformamide, N-methyl-N-vinylacetamide, cinnamic amide and cyclic amide (N-vinylpyrrolidone, N-allylpyrrolidone, etc.).
(A6) a quaternary ammonium base-containing vinyl monomer;
A quaternized product of a tertiary amino group-containing vinyl monomer having 6 to 50 carbon atoms (preferably 8 to 20 carbon atoms, such as methyl chloride, dimethyl sulfate, benzyl chloride and dimethyl carbonate), for example, dimethyl Examples include quaternized products of aminoethyl (meth) acrylate, quaternized products of diethylaminoethyl (meth) acrylate, quaternized products of dimethylaminoethyl (meth) acrylamide, and quaternized products of diethylaminoethyl (meth) acrylamide.
(A7) Polyether group-containing vinyl monomer:
Alkoxy (alkoxy group having 1 to 8 carbon atoms) polyalkylene (alkylene group having 2 to 4 carbon atoms) glycol mono (meth) acrylate [methoxypolyethylene glycol (degree of polymerization 2 to 40) mono (meth) acrylate and methoxypolypropylene glycol ( Polymerization degree 2-30) mono (meth) acrylate, etc.].

  Of these, (a) is preferably (a1) and (a2), particularly (a1) from the viewpoint of imparting sufficient developability.

  Examples of the hydrophobic group-containing vinyl monomer (b) include the following nonionic monomers (b1) to (b6).

(B1) (meth) acrylic acid ester;
C1-C20 alkyl (meth) acrylate of an alkyl group [for example, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, n-hexyl (meth) acrylate and 2-ethylhexyl (meth) acrylate, etc.]; alicyclic group-containing (meth) acrylate [dicyclopentanyl (meth) acrylate, sidiclopentenyl (meth) acrylate, isobornyl (meth) acrylate, etc. ];

(B2) an aromatic hydrocarbon monomer;
And hydrocarbon monomers having a styrene skeleton [for example, styrene, α-methylstyrene, vinyltoluene, 2,4-dimethylstyrene, ethylstyrene, isopropylstyrene, butylstyrene, phenylstyrene, cyclohexylstyrene, and benzylstyrene] and vinylnaphthalene. It is done.
(B3) carboxylic acid vinyl ester;
Examples thereof include those having 4 to 50 carbon atoms, such as vinyl acetate, vinyl propionate and vinyl butyrate.
(B4) vinyl ether monomers;
Those having 3 to 50 (preferably 6 to 20) carbon atoms such as vinyl methyl ether, vinyl ethyl ether, vinyl propyl ether, vinyl butyl ether and the like can be mentioned.
(B5) vinyl ketone monomer;
Examples thereof include those having 4 to 50 carbon atoms, such as vinyl methyl ketone, vinyl ethyl ketone, and vinyl phenyl ketone.
(B6) a halogen atom-containing monomer;
Examples thereof include those having 2 to 50 (preferably 2 to 20) carbon atoms, such as vinyl chloride, vinyl bromide, vinylidene chloride, chlorostyrene and bromostyrene.

  Among (b), (b1) is preferable from the viewpoint of photocuring reactivity, and alicyclic group-containing (meth) acrylate is more preferable.

  In (A1), the charged monomer molar ratio of (a) / (b) is usually 10 to 100/0 to 90, preferably 10 to 80/20 to 90, more preferably from the viewpoint of photocuring reactivity and developability. Is 25-85 / 15-75.

(A1) may contain a (meth) acryloyl group in the side chain for the purpose of further improving photocuring reactivity in the polymer having (a) and, if necessary, (b) as a constituent monomer. Good.
Examples of the method of incorporating a (meth) acryloyl group in the side chain include the following methods (1) and (2).
(1): A polymer is produced using a monomer having a group capable of reacting with an isocyanate group (such as a hydroxyl group or a primary or secondary amino group) in at least a part of (a), and then (meth) A method of reacting a compound having an acryloyl group and an isocyanate group (such as acryloylethyl isocyanate);
(2); producing a polymer using a monomer having a group capable of reacting with an epoxy group (hydroxyl group, carboxyl group, primary or secondary amino group, etc.) in at least a part of (a); A method of reacting a compound having a (meth) acryloyl group and an epoxy group (such as glycidyl acrylate).

  The number average molecular weight of (A1) (hereinafter abbreviated as Mn. The measured value by gel permeation chromatography) is preferably 500 to 500, from the viewpoint of photocuring reactivity and developability as the photosensitive resin composition. 000, more preferably 1,000 to 100,000, and particularly preferably 3,000 to 20,000.

(A1) can be obtained by performing polymerization with a radical polymerization initiator after the monomer is diluted with a solvent (F4) (hereinafter sometimes simply referred to as (F4)) if necessary. Solvents (F4) include glycol ethers (such as ethylene glycol monoalkyl ether and propylene glycol monoalkyl ether), ketones (such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone), and esters (butyl acetate, ethylene glycol alkyl). Ether acetate and propylene glycol alkyl ether acetate). Of (F4), ketones and esters are preferred.
When (F4) is used, the amount used is not particularly limited, but is usually 1 to 400% based on the total weight of the monomers (in the following,% represents% by weight unless otherwise specified), preferably 5 to 5%. 300%, particularly preferably 10 to 200%.
Examples of the polymerization initiator include peroxides and azo compounds.
Peroxides include inorganic peroxides (eg, hydrogen peroxide, ammonium persulfate, potassium persulfate, sodium persulfate, etc.) and organic peroxides (eg, benzoyl peroxide, di-t-butyl peroxide, Cumene hydroperoxide, lauryl peroxide, etc.). Examples of the azo compound include azobis (2,4-dimethylvaleronitrile), azobisisobutyronitrile, azobis (2-methylbutyronitrile), azobiscyanovaleric acid and its salts (for example, hydrochloride), and azobis (2 -Amidinopropane) hydrochloride and the like. Preferred is an azo compound. As a usage-amount of a polymerization initiator, 0.0001-20% is preferable normally based on the total weight of a monomer, More preferably, it is 0.001-15%, Most preferably, it is 0.005-10%. The reaction temperature and reaction time are appropriately determined depending on the type of radical polymerization initiator.

  As described above, the hydrophilicity index of (A) is defined by HLB. Of these, the HLB value of (A1) is preferably 9 to 19, more preferably 10 to 18, particularly preferably 11 to 17. It is. If the HLB of (A1) is 9 or more, developability can be further improved.

In the present invention, the hydrophilic epoxy polymer (A2) (hereinafter sometimes simply referred to as (A2)) of (A) is an epoxy resin skeleton containing a functional group having hydrophilicity such as a hydroxyl group or a carboxyl group. It is a polymer having
(A2) preferably has a (meth) acryloyl group in the molecule from the viewpoint of photocuring reactivity.

A preferred process for the preparation of (A2) an epoxy resin (A2 ₀₎ to epoxy group (hereinafter sometimes referred to simply as (A2 ₀₎₎ in, by reacting (meth) acryloyl group-containing monocarboxylic acid epoxy A method of reacting a part of the hydroxyl group with a polyvalent carboxylic acid or a polyvalent carboxylic acid anhydride (e) (hereinafter sometimes simply referred to as (e)). is there.

Examples of (A2 ₀ ) include aliphatic epoxy resins [eg, Etototo YH-300, PG-202, PG-207 (all manufactured by Tohto Kasei Co., Ltd.)] and alicyclic epoxy resins [eg, CY-179, CY-177. CY-175 (all manufactured by Asahi Kasei Epoxy Co., Ltd.)] and aromatic epoxy resins [eg, phenol novolac epoxy resin, cresol novolac epoxy resin, bisphenol A epoxy resin, biphenyl type epoxy resin and glycidyl modified polyvinylphenol] Can be mentioned.
Among (A2 ₀ ), an aromatic epoxy resin is preferable from the viewpoint of curability.
Examples of the (meth) acryloyl group-containing monocarboxylic acid used for the production of (A2) include acrylic acid and methacrylic acid.
Examples of the polyvalent carboxylic acid and polyvalent carboxylic acid anhydride (e) used in the production of (A2) include the unsaturated polyvalent carboxylic acids and anhydrides of the above-mentioned (a), and saturated polyvalent carboxylic acids. (2-6 valent) carboxylic acids (eg, aliphatic saturated polyvalent carboxylic acids such as oxalic acid, succinic acid, phthalic acid, adipic acid, dodecanedioic acid, dodecenyl succinic acid, pentadecenyl succinic acid and octadecenyl succinic acid) Acids; aromatic polycarboxylic acids such as tetrahydrophthalic acid, hexahydrophthalic acid, methyltetrahydrophthalic acid, trimellitic acid, pyromellitic acid, biphenyltetracarboxylic acid and naphthalenetetracarboxylic acid) and their anhydrides (for example, Succinic anhydride, dodecenyl succinic anhydride, pentadecenyl succinic anhydride, octadecenyl succinic anhydride, etc. Aliphatic saturated polycarboxylic anhydrides; phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, biphenyltetracarboxylic anhydride and naphthalenetetracarboxylic Aromatic polyhydric carboxylic acid anhydrides such as acid anhydrides). A saturated polycarboxylic acid anhydride is preferable from the viewpoint of reactivity and developability.

In the production of (A2), the charged weight ratio of (meth) acrylic acid / (A2 ₀ ) is preferably such that the concentration of the (meth) acryloyl group in (A2) is 1.0 mmol / g or more (meta ) Acrylic acid charge weight ratio. From the above viewpoint, the weight ratio of acrylic acid / (A2 ₀ ) is preferably 0.072 or more / 1, and more preferably 0.079 to 0.72 / 1. The weight ratio of methacrylic acid is preferably 0.092 or more / 1, more preferably 0.10 to 0.92 / 1, from the above viewpoint.
The reaction temperature in the reaction between (A2 ₀ ) and (meth) acrylic acid is not particularly limited, but is preferably 70 to 110 ° C. The reaction time is not particularly limited, but is preferably 5 to 30 hours. Further, if necessary, a catalyst (for example, triphenylphosphine) and a radical polymerization inhibitor (hydroquinone, p-methoxyphenol, etc.) may be used.
The charged equivalent of the polyvalent carboxylic acid or polyvalent carboxylic acid anhydride (e) with respect to the weight of the (meth) acrylic acid adduct of (A2 ₀ ) is such that the acid value of (A2) is preferably 10 to 500 mgKOH. For example, when (e) is a divalent carboxylic acid or an anhydride thereof, (e) the charge equivalent of (e) / (A20 ₀ ) (meth) acrylic acid From the above viewpoint, the weight of the adduct is preferably 0.18 to 8.9 meq / g, and more preferably 0.53 to 7.1 meq / g.
The reaction temperature in the reaction of the (A2 ₀ ) (meth) acrylic acid adduct and (e) is not particularly limited, but is preferably 70 to 110 ° C. The reaction time is not particularly limited, but is preferably 3 to 10 hours.

  Mn of (A2) is usually 500 to 3,000, preferably 1,000 to 2,800, particularly preferably 1,500 to 2, from the viewpoint of photocuring reactivity and developability as the photosensitive resin composition. , 500.

  The HLB value of (A2) is preferably 4 to 14, more preferably 5 to 13, and particularly preferably 6 to 12. If the HLB of (A2) is 4 or more, the developability can be exhibited satisfactorily, and if it is 14 or less, compatibility with the polyfunctional (meth) acrylate monomer (B) described later can be ensured.

  In the photosensitive resin composition (Q) of the present invention, (A) is preferably 10 to 70%, more preferably 15 to 60%, particularly preferably 20 to 50% based on the solid content weight of (Q). contains. If it is 10% or more, the developability can be further improved, and if it is 70% or less, the elastic recovery property of the cured product is further improved. In the present invention, “solid content” refers to components other than the solvent.

  In the present invention, the polyfunctional (meth) acrylate monomer (B) (hereinafter sometimes simply referred to as (B)) used as one component in the photosensitive resin composition is a known polyfunctional (meta) The acrylate monomer is not particularly limited, and examples thereof include bifunctional (meth) acrylate (B1), trifunctional (meth) acrylate (B2), and 4-6 functional (meth) acrylate (B3).

  Examples of the bifunctional (meth) acrylate (B1) include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, and polyethylene glycol di (meth). Acrylate, polypropylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, glycerin di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate ( SP value of methacrylate = 12.5, SP value of acrylate = 10.3), 1,9-nonanediol di (meth) acrylate, 1,10-decandiol di (meth) acrylate, 3-methyl-1, -Pentanediol di (meth) acrylate, 2-butyl-2-ethyl-1,3-propanediol di (meth) acrylate, dimethylol-tricyclodecane di (meth) acrylate, di (ethylene oxide adduct of bisphenol A ( Examples include (meth) acrylate, di (meth) acrylate of propylene oxide adduct of bisphenol A, and neopentyl glycol di (meth) acrylate of hydroxypivalate.

  As trifunctional (meth) acrylate (B2), glycerin tri (meth) acrylate, trimethylolpropane tri (meth) acrylate (SP value of methacrylate = 12.5, SP value of acrylate = 10.3), pentaerythritol tri Examples include (meth) acrylate (SP value of methacrylate = 12.5, SP value of acrylate = 10.3), tri (meth) acrylate of ethylene oxide adduct of trimethylolpropane, and the like.

  As the 4- to 6-functional (meth) acrylate (B3), pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate (methacrylate SP value = 12.5, acrylate SP value = 10.3), Examples include dipentaerythritol hexa (meth) acrylate (SP value of methacrylate = 12.5, SP value of acrylate = 10.3).

  The SP value of (B) is preferably 8 to 13, more preferably 9 to 13, particularly from the viewpoint of easily setting the difference from the SP value of (C) described later to -2.0 to 2.0. 9-12, especially 9.5-11.

  Among (B), preferred are (B2) and (B3), and more preferred is a polymer containing a hydroxyl group from the viewpoint of compatibility with (C) described later, particularly preferably dipentaerythritol pentaacrylate, Pentaerythritol triacrylate and combinations thereof. As (B) which can be easily obtained from the market, for example, Aronix M-403 (manufactured by Toagosei Co., Ltd.), light acrylate PE-3A (manufactured by Kyoeisha Chemical Co., Ltd.), neomer DA-600 (Sanyo Chemical Industries ( Etc.).

Moreover, (B) in this invention may contain the photosensitive acrylic oligomer (B4) in the one part. Examples of (B4) include urethane acrylate, polyester acrylate, and polyether acrylate having Mn of 1,000 or less and containing no carboxyl group and having two or more acryloyl groups in one molecule.
The content of (B4) in (B) is preferably 50% or less, more preferably 30% or less.

  The content of (B) based on the weight of the solid content of (Q) is preferably 10 to 70%, more preferably 20 to 65%, and particularly preferably 25 to 60%. If it is 10% or more, the elastic recovery property of the cured product is further preferable, and if it is 70% or less, the developability is further improved.

In the present invention, the polysiloxane (C) having two or more hydrolyzable alkoxy groups contained as a component in the photosensitive resin composition (Q) is a silane compound (c1) represented by the general formula (1). It is a condensate in which a part of the alkoxy group [OR ³ in general formula (1)] is polymerized by condensation reaction as an essential constituent monomer.

In the formula, R ¹ and the alkyl group having 1 to 6 carbon atoms are one or more selected from the group consisting of a (meth) acryloyloxyalkyl group, a glycidoxyalkyl group, a mercaptoalkyl group, and an aminoalkyl group. R ² is an aliphatic saturated hydrocarbon group having 1 to 12 carbon atoms or an aromatic hydrocarbon group having 6 to 12 carbon atoms, R ³ is an alkyl group having 1 to 4 carbon atoms, and m is 0 or 1. is there.

R ¹ does not react in the condensation reaction step (c1) but remains in the polysiloxane (C) even after the condensation reaction, and contributes to the thermosetting reaction when the photosensitive resin composition of the present invention is thermoset. It is a functional group.
R ¹ is preferably a (meth) acryloyloxyalkyl group or a glycidoxyalkyl group from the viewpoint of curability.

Among R ² , examples of the aliphatic saturated hydrocarbon group include a linear alkyl group, a branched alkyl group, and an alicyclic saturated hydrocarbon group.
Examples of linear alkyl groups include methyl, ethyl, n-propyl, n-butyl, n-octyl and n-dodecyl groups and their deuterium substitutes, and examples of branched alkyl groups include isopropyl, isobutyl, sec-butyl and 2- Examples of the ethylhexyl group and the cyclic saturated hydrocarbon group include a cyclohexyl group, a cyclooctyl group, a cyclohexylmethyl group, a cyclohexylethyl group, and a methylcyclohexyl group.
Examples of the aromatic hydrocarbon group include an aryl group, an aralkyl group, and an alkylaryl group.
As aryl groups, phenyl, biphenyl, naphthyl groups and their deuterium, fluorine or chlorine substituents; As aralkyl groups, tolyl, xylyl, mesityl and their deuterium, fluorine or chloride; and as alkylaryl groups Examples include methylphenyl and ethylphenyl groups.
R ² is preferably a linear alkyl group, branched alkyl group and aryl group from the viewpoint of curing reactivity, more preferably a linear alkyl group and aryl group, particularly preferably a methyl group, an ethyl group, a phenyl group and These are combined.
Examples of R ³ include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, and a sec-butyl group, and a methyl group and an ethyl group are preferable from the viewpoint of thermosetting reactivity. .

In the general formula (1), examples of the silane compound having a (meth) acryloyloxyalkyl group as R ¹ include the following compounds.
m is 0, that is, trifunctional silane compound having three alkoxy groups: 3-methacryloyloxypropyltrimethoxysilane, 3-methacryloyloxypropyltriethoxysilane, 3-acryloyloxypropyltrimethoxysilane, 3- Acryloyloxypropyltriethoxysilane and the like m is 1, that is, a trifunctional silane compound having two alkoxy groups: 3-methacryloyloxypropylmethyldimethoxysilane, 3-methacryloyloxypropylmethyldiethoxysilane, 3-acrylic Leuoxypropylmethyldimethoxysilane, 3-acryloyloxypropylmethyldiethoxysilane, etc.

Examples of the silane compound having a glycidoxyalkyl group as R ¹ include the following compounds.
m is 0, that is, trifunctional silane compound having 3 alkoxy groups, such as 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, etc. m is 1, that is, 3 having 2 alkoxy groups Functional silane compounds: 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, etc.

Examples of the silane compound having a mercaptoalkyl group as R ¹ include the following compounds.
m is 0, that is, a trifunctional silane compound having three alkoxy groups, such as 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, etc. m is 1, that is, a trifunctional silane compound having two alkoxy groups. ..3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropylmethyldiethoxysilane, etc.

Examples of the silane compound having an aminoalkyl group as R ¹ include the following compounds.
m is 0, that is, trifunctional silane compound having three alkoxy groups: N-2 aminoethyl γ-aminopropyltrimethoxysilane, N-2 aminoethyl γ-aminopropyltriethoxysilane, 3-aminopropyltrimethoxy Silane, 3-aminopropyltriethoxysilane, etc. m is 1, that is, a trifunctional silane compound having two alkoxy groups: N-2 aminoethyl γ-aminopropylmethyldimethoxysilane, N-2 aminoethyl γ-aminopropyl Methyldiethoxysilane, 3-aminopropylmethyldimethoxysilane, 3-aminopropylmethyldiethoxysilane, etc.

Among (c1), preferred from the viewpoint of curing reactivity is a silane compound in which R ¹ in the general formula (1) has a (meth) acryloyloxyalkyl group or a glycidoxyalkyl group,
More preferred are (meth) acryloyloxyalkyl group-containing trifunctional silane compounds having 3 alkoxy groups, and glycidoxyalkyl group-containing trifunctional silane compounds having 3 alkoxy groups, and particularly preferred are 3-acryloyloxypropyltrimethoxysilane and 3-glycidoxypropyltrimethoxysilane.

Examples of (C) include a homocondensation polymer composed only of the silane compound (c1), and a cocondensate of one or more other silane compounds (c2) capable of cocondensing with (c1) and (c1). .
Examples of the other silane compound (c2) include a silane compound represented by the general formula (2).
R ² nSi (OR ³ ) 4−n (2)
In the formula, R ² is an aliphatic saturated hydrocarbon group having 1 to 12 carbon atoms or an aromatic hydrocarbon group having 6 to 12 carbon atoms, R ³ is an alkyl group having 1 to 4 carbon atoms, and n is 0 It is an integer of ~ 2.

Examples of R ² and R ³ include those exemplified above.
Among R ^2, a linear alkyl group, a branched alkyl group and an aryl group are preferable, a linear alkyl group and an aryl group are more preferable, and a methyl group, an ethyl group, a phenyl group and a combination thereof are particularly preferable.
R ³ is preferably a methyl group or an ethyl group.

In the general formula (2), examples of the tetrafunctional silane compound in which n is 0, that is, four alkoxy groups include tetramethoxysilane and tetraethoxysilane.
Examples of the trifunctional silane compound in which n is 1, that is, three alkoxy groups include phenyltrimethoxysilane, phenyltriethoxysilane, methyltrimethoxysilane, and methyltriethoxysilane.
Examples of the bifunctional silane compound in which n is 2, that is, two alkoxy groups include diphenyldimethoxysilane, diphenyldiethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, phenylmethyldimethoxysilane, and phenylmethyldiethoxysilane. .
Of these, n is preferably 1, that is, a trifunctional silane compound from the viewpoint of forming a uniform network of polysiloxane (C).

  The charging ratio of the other silane compound (c2) is preferably from the viewpoint of curing reactivity, and the total amount of the other silane compound (c2) is preferably 0.1 to 6.0 mol, more preferably 1 mol of (c1). 0.2 to 4.0 moles is good.

  The polysiloxane (C) is, for example, 20 to 100 ° C. in a dry atmosphere with stirring a predetermined amount of water and, if necessary, the catalyst in the silane compound (c1) and other silane compound (c2) used as necessary. In about 10 minutes to 60 minutes, and then aged for 1 to 12 hours at a temperature below the boiling point of the by-produced alcohol (for example, 0 to 150 ° C.) to obtain a condensation reaction.

  When the amount of water added in the condensation reaction is X mol and the number of moles of alkoxy groups in the silane compound (c1) and the other silane compound (c2) is Y, if X / Y is too small, the yield of the condensate The molecular weight decreases. On the other hand, when X / Y is too large, the molecular weight becomes too large and the storage stability tends to decrease. From this, it is preferable to carry out in the range of 0.1 <X / Y <5, preferably in the range of 0.3 <X / Y <3. As the water to be added, ion exchange water or distilled water is usually used. Moreover, the silane compound which has one alkoxy group can also be added for the purpose of molecular weight adjustment. Examples of the silane compound having one alkoxy group include phenyltrimethoxysilane and methyltrimethoxysilane.

Condensation reaction catalysts include formic acid, acetic acid, succinic acid, lactic acid, malonic acid, citric acid, tartaric acid, malic acid, succinic acid, fumaric acid, phthalic acid, pyromellitic acid, p-toluenesulfonic acid, methanesulfonic acid, trifluoro Monovalent, divalent or trivalent organic acids such as acetic acid and trifluoromethanesulfonic acid; inorganic acids such as hydrochloric acid, phosphoric acid, nitric acid, hydrofluoric acid, bromic acid, chloric acid and perchloric acid; alkali metal hydroxides; Alkaline earth hydroxides, quaternary alkylammonium hydroxides and carbonates and alkali salts such as primary to tertiary amines; quaternary alkylammonium halides; sodium hypochlorite; tin, zirconium, titanium , Alkoxides of metals other than silicon such as aluminum and boron, and their chelate complexes; Organic acid among this, an inorganic acid, a metal alkoxide, an acid catalyst is preferable, chelate compounds of a metal alkoxide, an organic acid is particularly preferred.
The added amount of the catalyst is 0.0001 to 10 parts by weight, preferably 0.001 to 1 part by weight, based on 100 parts by weight of the total of (c1) and (c2). The method for adding the catalyst is not particularly limited, but it is preferably added as an aqueous solution. Moreover, preferable reaction temperature is 20 to 100 degreeC.

(C) preferably has a difference in SP value from the polyfunctional (meth) acrylate monomer (B) of −2.0 to 2.0, more preferably 0 from the viewpoint of compatibility and the elastic recovery property of the cured product. ˜1.9, particularly preferably 0.5 to 1.9, particularly preferably 1-1.85.
The SP value of (C) is preferably 7 to 13, more preferably 8 to 12, especially from the viewpoint that the difference from the SP value of (B) described above can be easily set to -2.0 to 2.0. 8-11, especially 8-10.5.

  The content of (C) based on the weight of the solid content of the photosensitive resin composition (Q) is preferably 1 to 50%, more preferably 3 to 40%, and particularly preferably 5 to 30%. If it is 5% or more, the flexibility and the elastic recovery property can be exhibited more satisfactorily, and if it is 40% or less, the compatibility can be further improved.

  Mn of (C) is preferably from 500 to 100,000, more preferably from 1,000 to 50,000, particularly preferably from 2,000 to 50,000, from the viewpoint of flexibility and elastic recovery characteristics when it becomes a photospacer. 20,000.

  Examples of the radical photopolymerization initiator (D) used as one component in the photosensitive resin composition (Q) include benzyl dimethyl ketal, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl. Propan-1-one, benzophenone, methylbenzoyl formate, isopropylthioxanthone, 4,4-bis (dimethylamino) benzophenone, 3,3-dimethyl-4-methoxy-benzophenone, anthraquinone, 2-methylanthraquinone, 2-ethylanthraquinone , Tert-butylanthraquinone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy Cetophenone, 2-hydroxy-2-methylpropiophenone, 4-isopropyl-2-hydroxy-2-methylpropiophenone, 2-methyl-1- (4- (methylthio) phenyl) -2-morpholino-1-propanone 2-chlorothioxanthone, diethylthioxanthone, isopropylthioxanthone, diisopropylthioxanthone, Michler's ketone, benzyl-2,4,6- (trihalomethyl) triazine, 2- (o-chlorophenyl) -4,5-diphenylimidazolyl dimer, 9 -Phenylacridine, 1,7-bis (9-acridinyl) heptane, 1,5-bis (9-acridinyl) pentane, 1,3-bis (9-acridinyl) propane, dimethylbenzyl ketal, trimethylbenzoyldiphenylphosphine Sid, tribromomethylphenylsulfone and 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) - butan-1-one, and the like. (D) may be used alone or in combination of two or more.

  (D) can be easily obtained as a commercially available product. For example, as 2-methyl-1- (4- (methylthio) phenyl) -2-morpholino-1-propanone, Irgacure 907, 2-benzyl- Examples of 2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one include Irgacure 369 (manufactured by Ciba Specialty Chemicals).

  The content of (D) based on the weight of the solid content of the photosensitive resin composition (Q) is preferably 0.01 to 10%, more preferably 0.05 to 8%. If it is 0.01% or more, the photocuring reactivity can be exhibited more satisfactorily, and if it is 8% or less, the resolution can be further improved.

  In the photosensitive resin composition (Q), the content of (D) with respect to the total weight of (A) when it has (B) and (meth) acryloyl groups is 0.02 to 15% from the viewpoint of curability. It is preferable that it is 0.05 to 10%.

  The photosensitive resin composition (Q) may further contain other components (E) as necessary. (E) includes inorganic fine particles (E1), sensitizer (E2), polymerization inhibitor (E3), solvent (E4), acid generator (E5), and other additives (E6) (for example, inorganic Pigments, silane coupling agents, dyes, fluorescent brighteners, yellowing inhibitors, antioxidants, antifoaming agents, deodorants, fragrances, bactericides, antibacterial agents, and fungicides.

As the inorganic fine particles (E1), metal oxides and metal salts can be used.
Examples of the metal oxide include titanium oxide, silicon oxide, and aluminum oxide.
Examples of the metal salt include calcium carbonate and barium sulfate.
Of these, metal oxides are preferable from the viewpoint of heat-resistant transparency and chemical resistance, and silicon oxide and titanium oxide, and particularly silicon oxide are more preferable.
The inorganic fine particles have a volume average primary particle diameter of 1 to 200 nm, preferably from 1 to 150 nm, more preferably from 1 to 120 nm, and particularly preferably from 5 to 20 nm, from the viewpoint of transparency.

  The content of (E1) based on the weight of the solid content of the photosensitive resin composition (Q) is usually 0 to 50%, preferably 1 to 45%, particularly preferably 2 to 40%. If it is 50% or less, the developability can be further improved, and if it is 2 to 40%, the elastic recovery property is particularly excellent.

  As the sensitizer (E2), nitro compounds (for example, anthraquinone, 1,2-naphthoquinone, 1,4-naphthoquinone, benzanthrone, p, p'-tetramethyldiaminobenzophenone, carbonyl compounds such as chloranil, nitrobenzene, p -Dinitrobenzene and 2-nitrofluorene etc.), aromatic hydrocarbons (eg anthracene and chrysene etc.), sulfur compounds (eg diphenyl disulfide etc.) and nitrogen compounds (eg nitroaniline, 2-chloro-4-nitroaniline) , 5-nitro-2-aminotoluene, tetracyanoethylene and the like.

  The content of the sensitizer (E2) based on the weight of the photopolymerization initiator (D) is usually 0.1 to 100%, preferably 0.5 to 80%, particularly preferably 1 to 70%.

  There is no limitation in particular as a polymerization inhibitor (E3), What is used for normal reaction is used. Specifically, diphenylhydrazyl, tri-p-nitrophenylmethyl, N- (3-N-oxyanilino-1,3-dimethylbutylidene) aniline oxide, p-benzoquinone, p-tert-butylcatechol, nitrobenzene, Examples include picric acid, dithiobenzoyl disulfide, and copper (II) chloride.

  The content of the polymerization inhibitor (E3) based on the weight of the solid content of the photosensitive resin composition (Q) is preferably 0 to 1.0%, more preferably 0.01 to 0.5%, particularly preferably. 0.02 to 0.1%.

  As the solvent, the same solvents as those used in the production of the above (A) can be used. When using a solvent, the compounding amount of the solvent is not particularly limited, but is preferably 50 to 1,000%, more preferably 70 to 900, based on the weight of the solid content of the photosensitive resin composition (Q). %, Particularly preferably 80 to 800%. In addition, the solvent used for manufacture of above-mentioned (A) and (C) is also contained in the compounding quantity of a solvent.

The acid generator (E5) is a compound that generates an acid by light or heat, and is added to accelerate the condensation reaction.
Examples of (E5) include the following (i) sulfone compounds, (ii) sulfonic acid ester compounds, (iii) sulfonimide compounds, (iv) disulfonyldiazomethane (v) disulfonylmethane, and (vi) onium salts. .
(I) Sulfone compounds Phenacylphenylsulfone, 4-trisphenacylsulfone-ketosulfone, β-sulfonylsulfone, and α-diazo compounds thereof (ii) Sulfonic acid ester compounds Benzoin tosylate, pyrogallol tris-trifluoromethanesulfonate, pyrogallolmethane (Iii) sulfonimide compounds N- (trifluoromethylsulfonyloxy) succinimide, N- (p-toluenesulfonyloxy) bicyclo [2.2] sulfonic acid triester, α-methylolbenzointosylate, α-methylolbenzoindodecylsulfonate, etc. .1] Hept-5-ene-2,3-dicarboximide, N- (perfluorooctanesulfonyloxy) naphthylimide, N- (benzenesulfonyloxy) bishi [2.2.1] Hept-5-ene-2,3-dicarboximide, N- (benzenesulfonyloxy) bicyclo [2.2.1] heptane-5,6-oxy-2,3-di Carboximide and N- (benzenesulfonyloxy) naphthylimide, etc. (iv) Disulfonyldiazomethane compounds Bis (trifluoromethylsulfonyl) diazomethane, bis (phenylsulfonyl) diazomethane, bis (p-toluenesulfonyl) diazomethane, bis (2,4 -Dimethylbenzenesulfonyl) diazomethane, bis (1-methylethylsulfonyl) diazomethane and bis (1,4-dioxaspiro [4,5] decane-7-sulfonyl) diazomethane etc. (v) onium salts sulfonium salts [bis [4- ( Diphenylsulfonio) phenyl] sulfide bi Suhexafluorophosphate, allylsulfonium hexafluorophosphate salt, etc.)
Iodonium salts (such as diphenyliodonium hexafluorophosphate), phosphonium salts (such as ethyltriphenylphosphonium tetrafluoroborate), diazonium salts (such as phenyldiazonium hexafluorophosphate), ammonium salts (1-benzyl-2-cyanopyridinium hexafluorophosphate, etc.) ), And ferrocene [(2,4-cyclopentadien-1-yl) [(1-methylethyl) benzene] -Fe (II) hexafluorophosphate, etc.), etc.

  Of (E5), preferred are a sulfonimide compound and a disulfonyldiazomethane compound, and more preferred are N- (trifluoromethylsulfonyloxy) succinimide and bis (phenylsulfonyl) diazomethane.

  The content of (E5) based on the weight of the solid content of the photosensitive resin composition (Q) is preferably 10% or less, more preferably 0.01 to 7%, and particularly preferably 0.05 to 5%. . If it is 0.001% or more, the elastic recovery property can be exhibited more satisfactorily, and if it is 10% or less, the developability can be further improved.

  The total content of (E) is usually 1,000% or less, preferably 80 to 800%, based on the weight of the photosensitive resin composition (Q).

The photosensitive resin composition (Q) of the present invention can be obtained, for example, by mixing the above-described components with a known mixing device such as a planetary mixer.
The photosensitive resin composition is usually liquid at room temperature, and its viscosity is 0.1 to 10,000 mPa · s, preferably 1 to 8,000 mPa · s at 25 ° C.

  Since the photosensitive resin composition (Q) of the present invention has good alkali developability and is excellent in the elastic recovery property of the cured product, the photosensitive resin for a photospacer provided especially for maintaining a gap in the liquid crystal cell. Suitable as a conductive resin composition.

The photo spacer of the present invention will be described below.
The photospacer of the present invention is a photospacer provided for maintaining a gap in a liquid crystal cell formed by curing the photosensitive resin composition (Q) by a process including light irradiation.
The photo spacer determines the gap of the liquid crystal cell when the color filter substrate and the TFT substrate are bonded together, and plays an important role for display quality. The height of the photo spacer usually has a constant height in the range of about 2 to 5 μm, and its uniformity is required. In addition to the height, the shape, size, density, and the like required for the photo spacer are appropriately determined depending on the design of the liquid crystal display device.

The preferable formation process of the photospacer of the present invention is a process in which, after light irradiation, alkali development is performed to form a pattern, followed by post-baking.
The formation of the photo spacer is usually performed in the following steps (1) to (5).
(1) The process of apply | coating the photosensitive resin composition of this invention on the transparent common electrode provided on the colored layer of a board | substrate.
Examples of the coating method include roll coating, spin coating, spray coating, and slit coating. Examples of the coating apparatus include spin coater, air knife coater, roll coater, bar coater, curtain coater, gravure coater, and comma coater. It is done.
The film thickness is usually 0.5 to 10 μm, preferably 1 to 5 μm.

(2) A step of drying (prebaking) the applied photosensitive resin composition layer by applying heat as necessary.
The drying temperature is preferably 10 to 100 ° C, more preferably 12 to 90 ° C, particularly 15 to 60 ° C, particularly 20 to 50 ° C. The drying time is preferably 0.5 to 10 minutes, more preferably 1 to 8 minutes, and particularly preferably 2 to 5 minutes. Drying may be performed under reduced pressure or normal pressure, but reduced pressure is preferred. Moreover, although it may carry out in air or in an inert gas, it is preferably in an inert gas.

(3) A step of exposing the photosensitive resin composition layer with actinic rays through a predetermined photomask.
In the case of the photosensitive resin composition of the present invention, even a mask opening having a diameter of about 5 to 10 μm (area of about 20 to 100 μm ² ) is accurate, that is, a range of 6 to 12 μm (area of 30 to 120 μm ² ). Can form a pattern.

Examples of the active light include visible light, ultraviolet light, and laser light. Examples of the light source include sunlight, a high-pressure mercury lamp, a low-pressure mercury lamp, a metal halide lamp, and a semiconductor laser.
Although it does not specifically limit as an exposure amount, Preferably it is 20-300 mJ / cm < ² >.
In the step of performing exposure, a component having a (meth) acryloyl group in the photosensitive resin composition reacts to undergo photocuring reaction.

(4) A step of developing by removing the unexposed portion with a developer.
As the developer, an alkaline aqueous solution is usually used. Examples of the alkaline aqueous solution include aqueous solutions of alkali metal hydroxides such as sodium hydroxide and potassium hydroxide; aqueous solutions of carbonates such as sodium carbonate, potassium carbonate and sodium hydrogencarbonate; hydroxytetramethylammonium and hydroxytetraethylammonium. An aqueous solution of an organic alkali can be mentioned. These can be used alone or in combination of two or more kinds, and a surfactant such as an anionic surfactant, a cationic surfactant, an amphoteric surfactant and a nonionic surfactant can be added and used.
As a developing method, there are a dip method and a shower method, but the shower method is preferable. The temperature of the developer is preferably 25 to 40 ° C. The development time is appropriately determined according to the film thickness and the solubility of the photosensitive resin composition.

(4) Post-heating (post-baking) step The post-baking temperature is preferably 100 to 250 ° C, more preferably 150 to 240 ° C, and particularly preferably 180 to 230 ° C. The post-baking time is 5 minutes to 6 hours, preferably 15 minutes to 4 hours, particularly preferably 30 minutes to 3 hours.
The baking may be performed under reduced pressure or normal pressure, but reduced pressure is preferred. Moreover, although it may carry out in air or in an inert gas, it is preferably in an inert gas.
By performing post-baking, the elastic recovery characteristics of the photo spacer are further improved.
In the post-heating step, it is presumed that a component having a thermosetting functional group in the photosensitive resin composition reacts and is thermoset.
Examples of the thermosetting functional group include hydrolyzable alkoxy group, glycidyl group, mercapto group or amino group in (B), and (meth) acryloyl group in (A) or (B). The trace amount (meth) acryloyl group etc. which remain | survived in said exposure process are mentioned.

The photo spacer of the present invention obtained as described above is a photo spacer excellent in flexibility and elastic recovery characteristics.
The flexibility of the photo spacer can be evaluated by the “total deformation amount” when pressure is applied. The larger the total deformation, the better the flexibility.
The elastic recovery characteristic of the photo spacer can be evaluated by the “elastic recovery rate” when pressure is applied. The higher the elastic recovery rate, the better the elastic recovery rate.

In the present invention, the flexibility and elastic recovery characteristics can be evaluated by measuring the following “total deformation amount, elastic recovery rate in a pressure range of 0.2 to 0.8 mN / μm ² ”.

Measuring method of “total deformation (μm)” and “elastic recovery rate (%)”;
At 25 ° C., a predetermined pressure is applied at a constant speed, held for one second, and then the total deformation amount T ₀ (from the hysteresis curve (FIG. 1) between the load and the deformation amount when the pressure is unloaded at a constant speed. μm) is obtained, and the plastic deformation amount T ₁ (μm) is obtained, and the elastic recovery rate (%) at a predetermined pressure is calculated by the following equation.
Elastic recovery rate (%) = [(T ₀ −T ₁ ) / T ₀ ] × 100
The ^{pressure, 0.2mN / μm 2, 0.4mN /} μm 2, the hysteresis curve measured at four different pressures of 0.6mN / μm ² and 0.8mN / μm ^2, the elastic recovery rate in each Ask for.

The total deformation amount of the photo spacer of the present invention is preferably 0.2 to 2.0 μm, more preferably 0.3 to 1.8 μm, and particularly preferably 0.4 to 0.2 mN / μm ² under pressure conditions. 1.5 μm. If the total deformation amount is 0.2 μm or more, there is a high possibility that it can be used practically as a spacer for holding the liquid crystal cell gap.

The elastic recovery rate of the photospacer of the present invention is preferably 70% or more, more preferably 75% or more, and particularly preferably 80% under any pressure condition of 0.2 to 0.8 mN / μm ^2. That's it. If the elastic recovery rate is 70% or more, particularly 75% or more, there is a high possibility that it can be used practically as a spacer for holding the liquid crystal cell gap.

[Example]
EXAMPLES Hereinafter, although an Example and a manufacture example demonstrate this invention concretely, this invention is not limited to these. Hereinafter, the part means part by weight.

[Production of hydrophilic polymer (A)]
<Production Example 1>
A glass Kolben equipped with a heating / cooling / stirring measure, a reflux condenser, a dropping funnel and a nitrogen inlet tube, isobornyl methacrylate 50 parts (33 mol%), 2-hydroxyethyl methacrylate 30 parts (33 mol%), methacryl 20 parts (34 mol%) of acid and 150 parts of cyclohexanenone were charged and heated to 80 ° C. A solution in which 5 parts of azobisisobutyronitrile (V-60: Wako Pure Chemical Industries, Ltd., hereinafter referred to as AIBN) prepared in advance is dissolved in 50 parts of cyclohexanone after replacing the gas phase part in the system with nitrogen. 55 parts are dropped into Kolben at 80 ° C. over 10 minutes, and further reacted at the same temperature for 3 hours to obtain a hydrophilic polymer (A-1) having a hydroxyl group and a carboxyl group (Mn: 8,800, SP value: 11. 86, HLB value: 11.98, weak acid value: 102 mg KOH / g) (solid content 25%). In addition, Mn is GPC measurement equipment (HLC-8120GPC, manufactured by Tosoh Corp.), column (TSKgel GMHXL 2 + TSKgel Multipore HXL-M, manufactured by Toso Corp.), polystyrene conversion measured by GPC method. Obtained as a value. The SP value, HLB value, and weak acid value were determined as described above. The same measurement method is used for the following production examples and comparative examples.

<Production Example 2>
In the same Kolben as in Production Example 1, 200 parts of a cresol novolac type epoxy resin “EOCN-1020” (manufactured by Nippon Kayaku, epoxy equivalent 200) and 245 parts of propylene glycol monomethyl ether acetate are charged and heated to 110 ° C. uniformly. Dissolved. Subsequently, 76 parts (1.07 mol part) of acrylic acid, 2 parts of triphenylphosphine, and 0.2 part of p-methoxyphenol were charged and reacted at 110 ° C. for 10 hours. The reaction product was further charged with 91 parts (0.60 mol part) of tetrahydrophthalic anhydride, further reacted at 90 ° C. for 5 hours, and after cooling, propylene glycol monomethyl ether acetate was added to adjust the solid content, and carboxyl group and acryloyl A propylene glycol monomethyl ether acetate solution of a hydrophilic polymer (A-2) having a group (Mn: 2,200, SP value: 11.26, HLB value: 6.42, acid value: 91 mgKOH / g) was obtained ( Solids content is 25%).

[Production of polysiloxane (C) having two or more hydrolyzable alkoxy groups]
<Production Example C-1>
In a glass Kolben equipped with a heating / cooling / stirring measure, a reflux condenser, a dropping funnel and a nitrogen introduction pipe, 46 parts (0.2 mole part) 3-acryloyloxypropyltrimethoxysilane, 160 parts diphenyldimethoxysilane (0 .65 mol parts), 45 g (2.5 mol parts) of ion-exchanged water, and 0.1 part (0.001 mol parts) of oxalic acid, and heated and stirred at 60 ° C. for 6 hours. The methanol by-produced by hydrolysis was removed over 2 hours under reduced pressure of 50 mmHg. Thereafter, the solution is diluted with cyclohexanone so that the solid content is 25%, and a cyclohexanone solution of polysiloxane (C-1) (Mn: 2,100, viscosity: 20 mPa · s, SP value: 9.36) is obtained. (The solid content was 25%). The viscosity was measured using a BL type viscometer (manufactured by Toki Sangyo Co., Ltd.) at a constant temperature of 25 ° C. The same measurement method is used for the following production examples and comparative examples.

<Production Example C-2>
In the same Kolben as in Production Example C-1, 170 parts (0.82 mole part) of 3-glycidoxypropyltrimethoxysilane, 40 parts (0.20 mole part) of phenyltrimethoxysilane, 30 parts of diphenyldimethoxysilane ( 0.12 mol part), 40 g (2.2 mol parts) of ion-exchanged water, and 0.1 part (0.001 mol part) of oxalic acid, and heated and stirred under conditions of 60 ° C. for 6 hours, and further an evaporator. Was used to remove methanol by-produced by hydrolysis over 2 hours under reduced pressure of 50 mmHg. Thereafter, the solution is diluted with cyclohexanone so that the solid content is 25%, and a cyclohexanone solution of polysiloxane (C-2) (Mn: 7,800, viscosity: 70 mPa · s, SP value: 8.69) is obtained. (The solid content was 25%).

<Comparative Production Example C-1 ′>
In the same Kolben as in Production Example C-1, 46 parts (0.34 mole part) of methyltrimethoxysilane, 160 parts (0.80 mole part) of phenyltrimethoxysilane and 45 g (2.5 mole parts) of ion-exchanged water Then, 0.1 part (0.001 mol part) of oxalic acid was charged, heated and stirred under the conditions of 60 ° C. and 6 hours, and further by using an evaporator, methanol produced as a by-product by hydrolysis was added under reduced pressure of 50 mmHg. Removed over time. Then, it was diluted with cyclohexanone so that the solid content was 25%, and cyclohexanone of comparative polysiloxane (C-1 ′) (Mn: 9,400, viscosity: 250 mPa · s, SP value: 8.49) A solution was obtained (solid content 25%).

<Comparative Production Example C-2 ′>
In the same Kolben as in Production Example C-1, 119 parts (1.14 mole part) of trimethylmonomethoxysilane, 45 g (2.5 mole part) of ion-exchanged water, and 0.1 part (0.001 mole part) of oxalic acid ), And heated and stirred at 60 ° C. for 6 hours. Further, by using an evaporator, methanol produced as a by-product by hydrolysis was removed under reduced pressure of 50 mmHg over 2 hours. Thereafter, the solution was diluted with cyclohexanone so that the solid content was 25%, and a cyclohexanone solution of comparative polysiloxane (C-2 ′) (Mn: 350, viscosity: 4 mPa · s, SP value: 6.75) was prepared. Obtained (solid content 25%).

<Examples 1-6 and Comparative Examples 1-4>
[Production of photosensitive resin composition]
According to the formulation example of Table 1, each hydrophilic polymer solution and polysiloxane solution are charged into a glass container, and the following (B-1), (D-1), and (E-1) are further charged. Stir until uniform, and further add an additional solvent (propylene glycol monomethyl ether acetate), photosensitive resin compositions (Q1) to (Q6) of Examples, and photosensitive resin composition (Y1) of Comparative Examples -(Y4) was manufactured. In addition, () in Table 1 represents the content of each component in terms of solid content in the photosensitive resin composition.

B-1 (polyfunctional (meth) acrylate): “Neomer DA-600” (mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate: manufactured by Sanyo Chemical Industries, Ltd.) (SP value: 10.55),
C-3 ′: One-terminal glycidyl group-modified polysiloxane (“X-22-173DX”: manufactured by Shin-Etsu Chemical Co., Ltd.) (viscosity: 65 mPa · s, SP value: 6.66)
D-1 (photo radical polymerization initiator): “Irgacure 907” (2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one: manufactured by Ciba Specialty Chemicals Co., Ltd. ),
E-1 (acid generator): N- (trifluoromethylsulfonyloxy) succinimide

[Evaluation of developability]
The photosensitive resin compositions (Q1) to (Q6) and (Y1) to (Y4) were each spin-coated on a glass substrate so that the finished film thickness was 5 μm, dried at 25 ° C. for 5 minutes, and then Development was performed for 30 seconds using a 1% aqueous sodium carbonate solution to evaluate developability. The results are shown in Table 1. The evaluation criteria are as follows.
A: There is no residue visually.
○: There is a slight residue visually.
Δ: There are many residues by visual inspection.

Examples 7-12, Comparative Examples 5-8
[Production of photo spacer]
The photosensitive resin compositions (Q1) to (Q6) and (Y1) to (Y4) were each spin-coated on a glass substrate so that the final film thickness was 5 μm, and dried at 25 ° C. for 5 minutes. The light of a high pressure mercury lamp was 100 mJ / cm ² irradiation through a photomask for forming photo spacers. Note that the exposure (gap) between the photomask and the substrate was 100 μm. Thereafter, development was performed using a 1% aqueous sodium carbonate solution. After washing with water, post-baking was performed at 230 ° C. for 60 minutes to form a photo spacer on the color filter. The upper base area of the photo spacer was 150 μm ² and the lower base area was 400 μm ² .
[Measurement of total deformation and elastic recovery rate]
The total deformation amount and elastic recovery rate of the photo spacer obtained as described above were measured using a Fischer scope H-100 (Fischer Instruments) apparatus.
A flat indenter (50 μm × 50 μm) having a square cross section was used. The results are shown in Tables 2 and 3.

As can be seen from Tables 1, 2 and 3, by using the photosensitive resin composition of the present invention, a photo spacer having good developability and excellent flexibility and elastic recovery characteristics can be formed. .
In Comparative Examples 1 to 3, since the polysiloxane in the used photosensitive resin compositions (Y1) to (Y3) does not have a functional group or two or more alkoxy groups, the necessary crosslinking reaction is sufficient. Does not progress to. In such a case, since the “shear” between molecules increases, the elastic recovery rate decreases. When a liquid crystal panel is produced using such a photo spacer, the cell gap is not uniform and the display quality is deteriorated.
In Comparative Example 4, the used photosensitive resin composition (Y4) does not contain polysiloxane, has a small total deformation amount, and is inferior in flexibility. When a liquid crystal panel is produced using such a photo spacer, the cell gap is not uniform and the display quality is deteriorated.

The photosensitive resin composition of this invention can be used conveniently for photospacers.
In addition, it is also suitable as a photosensitive resin composition for uses such as various resist materials such as a photo solder resist, a photosensitive resist film, a photosensitive resin relief plate, a screen plate, a photoadhesive or a hard coat agent.
Furthermore, coating agents for various materials such as metals (for example, iron, aluminum, titanium, copper, etc.), plastics (for example, polycarbonate, polyethylene terephthalate, poly (meth) acrylate), paper, glass, rubber and wood, paints, It can also be used as a printing ink and an adhesive, and can also be applied as a molding material.

Hysteresis curve of load and deformation

Explanation of symbols

T ₀ : Total deformation amount T ₁ : Plastic deformation amount T ₂ : Elastic deformation amount

Claims (6)

Containing a hydrophilic polymer (A), a polyfunctional (meth) acrylate monomer (B), a polysiloxane (C) having two or more hydrolyzable alkoxy groups, and a photoradical polymerization initiator (D), A photosensitive resin composition (Q) for a photospacer capable of alkali development, in which siloxane (C) is a condensate containing a silane compound (c1) represented by the following general formula (1) as an essential constituent monomer.

[Wherein, R ¹ is one selected from the group consisting of a (meth) acryloyloxyalkyl group, a glycidoxyalkyl group, a mercaptoalkyl group, and an aminoalkyl group, wherein the alkyl group has 1 to 6 carbon atoms. The above organic group, R ² is an aliphatic saturated hydrocarbon group having 1 to 12 carbon atoms or an aromatic hydrocarbon group having 6 to 12 carbon atoms, R ³ is an alkyl group having 1 to 4 carbon atoms, and m is 0 or 1 It is. ] The photosensitive resin composition (Q) according to claim 1, wherein (c1) is a silane compound in which R ¹ in the general formula (1) is a (meth) acryloyloxyalkyl group. The difference in solubility parameter between the polyfunctional (meth) acrylate monomer (B) and the compound (C) having two or more hydrolyzable alkoxy groups is -2.0 to 2.0. The photosensitive resin composition (Q) described. The content of the polysiloxane (C) having two or more hydrolyzable alkoxy groups is 5 to 30% by weight based on the weight of the solid content of the photosensitive resin composition (Q). Any photosensitive resin composition (Q). The photo-spacer formed by hardening the photosensitive resin composition in any one of Claims 1-4 by the process including light irradiation. 6. The photospacer according to claim 5, wherein the step including light irradiation is a step in which after light irradiation, alkali development is performed to form a pattern, and further post baking is performed.

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