KR20190026569A - Photosensitive composition for forming display device, cured film and display device - Google Patents

Abstract

The present invention relates to a photosensitive composition for forming a display device, which is suitable for forming a cured film having both a high light reflection function and a fine pattern shape, a cured film and a display device. The photosensitive composition for forming the display device comprises: (A) a white pigment; (B) an alkali-soluble resin; (C) a polymerizable compound; (D) a photopolymerization initiator; and (E) a solvent, wherein the content of (A) the white pigment is 30 to 90 wt% with respect to 100 wt% by mass of all components excluding (E) the solvent.

Description

TECHNICAL FIELD [0001] The present invention relates to a photosensitive composition for forming a display element, a cured film,

The present invention relates to a photosensitive composition for forming a display element, a cured film and a display element.

BACKGROUND ART In the field of display panels, fine patterns of resin are formed on a substrate for a display element protected by a bezel or the like (panel edge portion), and characteristics are given to these patterns to be used in various applications.

For example, in the light-emitting diode device, the above-described technique is used as a partition for partitioning the light to prevent color mixture (Patent Document 1). The use of such a barrier rib for suppressing the color mixture is not limited to the use of a light emitting portion such as an organic electroluminescence element (hereinafter abbreviated as an organic EL element) or a microsize light emitting diode element (hereinafter abbreviated as a micro LED element) Due to its miniaturization, it has become a particularly demanding technology in recent years.

WO2016 / 052025

Although Patent Document 1 discloses a barrier wall exhibiting excellent characteristics, there is room for improvement in the function of taking out the light emitted from the light-emitting portion and the formability of the barrier rib. That is, it is considered that the barrier described in Patent Document 1 suppresses the color mixture of light by reflecting the primary light emitted from the LED chip by the white pigment contained in the barrier rib, It is difficult to make it compatible with formation of a fine barrier rib pattern, and this point is not described at all in Patent Document 1.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and it is an object of the present invention to provide a photosensitive composition for forming a display element which is suitable for formation of a cured film that combines a high light reflection function and a fine pattern shape.

Means for Solving the Problems The present inventors have conducted intensive studies in order to solve the above problems. As a result, it has been found that a composition having the following composition is a suitable material for solving the above problems, and the present invention has been completed.

That is, an embodiment of the present invention is a photosensitive composition for forming a display element containing (A) a white pigment, (B) an alkali-soluble resin, (C) a polymerizable compound, (D) a photopolymerization initiator, and , And the content of the white pigment (A) is 30 to 90% by mass based on 100% by mass of all components excluding the solvent (E).

An embodiment of the present invention is a display element which is a cured film formed by using the photosensitive composition for forming a display element and a display element which is an organic EL element or a micro LED element having a partition and the partition is the cured film.

According to the photosensitive composition for forming a display element of the present invention, a cured film having a fine pattern shape can be formed. Further, the cured film formed has a high light reflection function. Therefore, by using a cured film formed of the photosensitive composition for forming a display element as the partition wall, it can be suitably used for forming a display element including a micro LED element, an organic EL element, and the like.

≪ Photosensitive composition for forming display element >

(A) a white pigment, (B) an alkali-soluble resin, (C) a polymerizable compound, (D) a photopolymerization initiator And (E) a solvent, wherein (A) the white pigment is contained in an amount of 30 to 90% by mass based on 100% by mass of all components excluding the solvent (E).

According to this composition, a cured film having a high light reflection function can be formed because it contains a relatively high concentration of (A) white pigment. Further, a cured film having a fine pattern shape of a desired shape can be easily formed by including the alkali-soluble resin (B), the polymerizable compound (C), and the photopolymerization initiator (D). This composition can be suitably used as a material for forming a fine structural member requiring a light reflection performance in a display element, and particularly as a material for forming a partition wall of an organic EL element or a micro LED element.

Each component will be described below.

≪ (A) White pigment >

Examples of the white pigment (A) include alumina, magnesium oxide, antimony oxide, titanium oxide, zirconium oxide, aluminum hydroxide, magnesium hydroxide, barium sulfate, magnesium carbonate, barium carbonate, calcium carbonate, lead sulfate, , Silicon dioxide, zinc oxide, tin oxide, strontium strontium, strontium titanate, barium tungstate, lead metasilicate, talc, kaolin, clay, bismuth chloride, hollow silica particles, organic hollow particles, core shell particles and the like have.

(A) the white pigment includes at least one kind of inorganic substance selected from the group consisting of alumina, magnesium oxide, antimony oxide, titanium oxide, zirconium oxide, aluminum hydroxide, magnesium hydroxide, barium sulfate, magnesium carbonate and barium carbonate And it is particularly preferable to include titanium oxide. Since the inorganic material has a high refractive index, the reflection characteristic of the formed cured film can be improved. Among them, titanium oxide has a particularly high refractive index and is also preferable from the viewpoint of dispersibility in a solvent.

The lower limit of the average particle diameter of the white pigment (A) is preferably 50 nm, more preferably 100 nm, and even more preferably 200 nm. On the other hand, the upper limit is preferably 700 nm, more preferably 500 nm, and further preferably 400 nm. When the average particle diameter of the white pigment (A) is in the above range, it is possible to exhibit good dispersibility and light scattering property, and as a result, the light reflectivity and light shielding property can be enhanced.

The content of the white pigment (A) in the composition is 30 to 90 mass%, preferably 40 to 85 mass%, more preferably 45 to 80 mass%, based on 100 mass% Is more preferable. The upper limit of the content of the white pigment (A) may be more preferably 75% by mass, 70% by mass, 65% by mass or 60% by mass. (A) When the content of the white pigment is 30 mass% or more, a cured film to be formed has high light reflection characteristics. On the other hand, when the content of the white pigment (A) is 90 mass% or less, adjustment of other components for forming a fine pattern is facilitated, and a fine pattern having a desired shape can be easily formed.

<(B) Alkali-soluble resin>

The alkali-soluble resin (B) is a resin that is soluble in an alkaline solvent and has alkali developability. The alkali-soluble resin (B) is not particularly limited as long as it is a resin having alkali developability. This composition can easily form a fine cured film having a desired pattern shape by containing (B) an alkali-soluble resin.

The alkali-soluble resin (B) preferably contains an acidic group. Examples of the acidic group include a carboxyl group, an acid anhydride group, a phenolic hydroxyl group and a sulfo group. Among the above, at least one acid group selected from the group consisting of a carboxyl group and a phenolic hydroxyl group is preferable, and a carboxyl group is more preferable. The alkali-soluble resin (B) is preferably a resin containing a structural unit having at least one acidic group.

As the alkali-soluble resin (B) having a carboxyl group, in particular, a copolymer of a monomer having at least one carboxyl group (hereinafter abbreviated as "carboxyl group-containing monomer") with another copolymerizable monomer (hereinafter abbreviated as "copolymerizable monomer" Coalescence is preferred.

Examples of the carboxyl group-containing monomer include unsaturated monocarboxylic acids such as (meth) acrylic acid, crotonic acid,? -Chloracrylic acid and cinnamic acid; Unsaturated dicarboxylic acids such as maleic acid, maleic anhydride, fumaric acid, itaconic acid, itaconic anhydride, citraconic acid, citraconic anhydride, and mesaconic acid, or anhydrides thereof; (Meth) acryloyloxyalkyl of a divalent or higher polyvalent carboxylic acid such as succinic acid mono [2- (meth) acryloyloxyethyl], phthalic acid mono [2- (meth) acryloyloxyethyl] ester; (meth) acrylate of a polymer having a carboxyl group and a hydroxyl group at both terminals, such as? -carboxypolycaprolactone mono (meth) acrylate. The carboxyl group-containing monomers may be used singly or in combination of two or more.

As the carboxyl group-containing monomer, (meth) acrylic acid, mono [2- (meth) acryloyloxyethyl] and ω-carboxypolycaprolactone mono (meth) acrylate are preferable, and (meth) acrylic acid is particularly preferable .

Examples of the monomer giving a structural unit having a phenolic hydroxyl group include 4-vinylphenol, 4-isopropenylphenol, 4-hydroxyphenyl (meth) acrylate and the like.

The content of the structural unit having an acidic group in the alkali-soluble resin (B) is preferably from 1 to 50 mass%, more preferably from 3 to 40 mass%, and even more preferably from 3 to 40 mass%, based on 100 mass% of the alkali- By mass to 5% by mass to 30% by mass. When the content of the structural unit having an acidic group is 1% by mass or more, the solubility of the present composition in an alkaline developer can be increased. On the other hand, when the content is 50% by mass or less, the solubility in an alkaline developer is prevented from becoming excessive, It is possible to sufficiently suppress the drop off from the substrate and the film roughness on the surface.

The alkali-soluble resin (B) preferably contains a Si (silicon) atom or an F (fluorine) atom, and particularly preferably contains an F atom. By including such an atom, the liquid-repelling property is imparted to the alkali-soluble resin (B). As a result, it becomes easy to apply a composition for forming a color filter or a composition for forming a phosphor layer or the like between the cured films formed by the present composition, and it becomes easy to form a display device having high functionality by using the cured film as a partition wall.

When the alkali-soluble resin (B) contains an F atom, it preferably contains a group represented by the following formula (1).

In formula (1), R ¹ and R ² are each independently a hydrogen atom or a fluorine atom, A is an ester bond or an ether bond, and n is an integer of 1 to 10. When n is 2 or more, a plurality of R ^{1 s} may be the same or different, and a plurality of R ^{2 s} may be the same or different. * Represents the binding site.

(B) The alkali-soluble resin has the group represented by the formula (1), so that the alkali-soluble resin (B) has appropriate liquid-repelling properties. As a result, it becomes easy to form a display device having high functionality as described above.

The lower limit of n in the formula (1) is preferably 3, more preferably 5. As the upper limit of n, 8 may be preferable.

The group represented by the formula (1) is preferably a group represented by the following formula (2) and the following formula (3).

In the formula (2), x is an integer of 0 to 2, y is an integer of 1 to 8, and the formula (3), z is an integer of 1 to 5.

The lower limit of x in the formula (2) is preferably 1, more preferably 2. The lower limit of y is preferably 2 and more preferably 4. As the upper limit of y, 6 may be preferable.

The A in the formulas (1) to (3) is preferably an ester bond. The ester bond is a divalent group represented by -C (= O) O-, and its direction is not limited. However, it is preferable that the bonding site (*) side is a carbonyl group (-C (= O) -).

The alkali-soluble resin (B) preferably contains a structural unit containing Si atom or F atom, more preferably a structural unit containing F atom. As the structural unit containing an F atom, a structural unit having a group represented by the above formula (1) is preferable. Examples of the monomer giving the structural unit having a group represented by the formula (1) include a monomer represented by the following formula (4).

In the formula (4), R ³ is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a fluorinated alkyl group having 1 to 4 carbon atoms. R ^f is a group represented by the above formula (1).

R ³ in the formula (4) is preferably a hydrogen atom or a methyl group.

Examples of the monomer giving a structural unit containing an Si atom include (meth) acrylate having a silyl group such as trimethylsilyl (meth) acrylate and triethylsilyl (meth) acrylate.

The content of the structural unit containing Si atom or F atom in the alkali-soluble resin (B) is preferably 1 to 70 mass% with respect to 100 mass% of the alkali-soluble resin (B). Within this range, it is easy to impart appropriate liquid-repelling properties to the alkali-soluble resin (B). The content of the structural unit containing Si atom or F atom is more preferably 3% by mass to 50% by mass, further preferably 5% by mass to 45% by mass based on 100% by mass of the alkali soluble resin (B) %to be. When the content of the structural unit containing Si atom or F atom is within this range, it is possible to further improve the developability of the composition in addition to the above effect. From the viewpoint of lyophobicity, the lower limit of the content of the structural unit containing Si atom or F atom is preferably 10% by mass, more preferably 20% by mass.

The alkali-soluble resin (B) preferably has a polymerizable group for improving sensitivity and the like, more preferably a structural unit containing a polymerizable group. As the polymerizable group, at least one member selected from the group consisting of a (meth) acryloyl group, a vinyl group, an oxiranyl group and an oxetanyl group is preferable. (B) Since the alkali-soluble resin has the above specific polymerizable group, the cured film formed by the composition of the present invention has a high surface hardening property, an excellent curing property, and an improved heat resistance.

Among these polymerizable groups, an oxiranyl group and an oxetanyl group are preferable, and an oxiranyl group is more preferable. Examples of the monomer giving the structural unit containing a polymerizable group include glycidyl (meth) acrylate, 3- (meth) acryloyloxymethyl-3-ethyloxetane, 3,4-epoxycyclohexylmethyl Acrylate, 3,4-epoxytricyclo [5.2.1.0 ^2.6 ] decyl (meth) acrylate, and the like.

The content of the structural unit having a polymerizable group in the alkali-soluble resin (B) is preferably 5% by mass to 60% by mass, more preferably 10% by mass to 55% by mass, relative to 100% by mass of the alkali- By mass, more preferably 20% by mass to 50% by mass.

The alkali-soluble resin (B) may also be a polymer containing a ring structure for improving heat resistance. The cyclic structure is preferably contained in the main chain of the alkali-soluble resin (B). The alkali-soluble resin (B) preferably has a structural unit containing a cyclic structure, more preferably a structural unit containing a cyclic structure in its main chain. The reduced water of the ring structure may be, for example, 3 to 12 or more, preferably 5 to 8.

Examples of the monomer giving a structural unit containing a cyclic structure include N-substituted maleimide monomer, dialkyl-2,2 '- (oxydimethylene) diacrylate monomer,? - (unsaturated alkoxyalkyl) acrylate, (Meth) acrylate, dicyclopentenyl (meth) acrylate, styrene, vinylphenyl ether, and the like. Also included are the monomers conferring the aforementioned structural unit having an oxiranyl group or oxetanyl group.

Among them, a copolymer introduced from at least one selected from the group consisting of N-substituted maleimide-based monomer, tricyclodecanyl (meth) acrylate and dicyclopentenyl (meth) acrylate has a high heat resistance .

Among these monomers, the N-substituted maleimide-based monomer is preferable because it can introduce a ring structure into the main chain and can exhibit better heat resistance. The N-substituted maleimide-based monomer is a compound in which a hydrogen atom bonded to the nitrogen atom in the maleimide is substituted by a substituent. The substituent is preferably a hydrocarbon group, more preferably a hydrocarbon group having a ring structure, and more preferably an aromatic hydrocarbon group. Examples of the N-substituted maleimide-based monomer include N-phenylmaleimide, N-naphthylmaleimide, N-cyclohexylmaleimide, N-cyclooctylmaleimide and N-methylmaleimide.

The content of the structural unit having a cyclic structure in the alkali-soluble resin (B) is preferably 5 to 80 mass%, more preferably 10 to 50 mass%, relative to 100 mass% of the alkali-soluble resin (B) , And more preferably 15 to 30 mass%.

The alkali-soluble resin (B) can be easily obtained by polymerization using one kind or two or more kinds of monomers among the above-mentioned carboxyl group-containing monomers and the like. In the synthesis of the alkali-soluble resin (B), other monomers other than the above-mentioned monomers may be arbitrarily used.

The alkali-soluble resin (B) may be used alone or in combination of two or more. Specific examples of the use of two or more (B) alkali-soluble resins include those in which an alkali-soluble resin having a large number of structural units containing an acidic group and an alkali-soluble resin containing a large amount of Si atoms or F atoms are used in combination . As described above, two or more kinds of alkali-soluble resins are classified and used in accordance with their functionalities, whereby the present composition having excellent display device formability can be obtained.

The weight average molecular weight (Mw) of the alkali-soluble resin (B) in terms of polystyrene is preferably 2,000 to 500,000, more preferably 3,000 to 100,000, more preferably 3,000 to 100,000, as measured by a gel permeation chromatography (GPC) More preferably 4,000 to 50,000.

When the Mw is in the above range, (B) an alkali-soluble resin having excellent solubility in a solvent or a developer can be obtained, and (B) an alkali-soluble resin having sufficient mechanical properties can be obtained.

The content of the alkali-soluble resin (B) is preferably from 10 to 150 parts by mass, more preferably from 20 to 70 parts by mass, and still more preferably from 25 to 50 parts by mass with respect to 100 parts by mass of the total amount of the (A) white pigment .

&Lt; (C) Polymerizable compound >

(C) a polymerizable compound means a compound having two or more polymerizable groups. However, the alkali-soluble resin (B) is excluded. Examples of the polymerizable group include an ethylenic unsaturated group, an oxiranyl group, an oxetanyl group and an N-alkoxymethylamino group. As the polymerizable compound, a compound having two or more (meth) acryloyl groups or a compound having two or more N-alkoxymethyl amino groups is preferable.

Specific examples of the compound having two or more (meth) acryloyl groups include a polyfunctional (meth) acrylate obtained by reacting an aliphatic polyhydroxy compound with (meth) acrylic acid, a caprolactone-modified polyfunctional (meth) acrylate , A polyfunctional urethane (meth) acrylate obtained by reacting a (meth) acrylate having a hydroxyl group with a polyfunctional isocyanate, a (meth) acrylate having a hydroxyl group and an acid anhydride (Meth) acrylate having a carboxyl group which is obtained by reacting a polyfunctional (meth) acrylate.

Examples of the aliphatic polyhydroxy compound include divalent aliphatic polyhydroxy compounds such as ethylene glycol, propylene glycol, polyethylene glycol and polypropylene glycol; And tri- or higher aliphatic polyhydroxy compounds such as glycerin, trimethylol propane, pentaerythritol and dipentaerythritol. Examples of the (meth) acrylate having a hydroxyl group include 2-hydroxyethyl (meth) acrylate, trimethylolpropane di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol penta (Meth) acrylate, and glycerol dimethacrylate. Examples of the polyfunctional isocyanate include tolylene diisocyanate, hexamethylene diisocyanate, diphenylmethylene diisocyanate, and isophorone diisocyanate. Examples of the acid anhydride include anhydrides of dibasic acids such as succinic anhydride, maleic anhydride, anhydrous glutaric acid, itaconic anhydride, phthalic anhydride, and hexahydrophthalic anhydride, anhydrous pyromellitic acid, biphenyltetracarboxylic acid dianhydride , And benzophenone tetracarboxylic acid dianhydride.

Examples of the caprolactone-modified polyfunctional (meth) acrylate include compounds described in paragraphs [0015] to [0018] of JP-A-11-44955. Examples of the alkylene oxide-modified polyfunctional (meth) acrylate include bisphenol A di (meth) acrylate modified with at least one member selected from ethylene oxide and propylene oxide, at least one member selected from ethylene oxide and propylene oxide Trimethylolpropane tri (meth) acrylate modified with at least one member selected from isocyanuric acid tri (meth) acrylate, ethylene oxide and propylene oxide modified by at least one of ethylene oxide, propylene oxide, (Meth) acrylate modified with at least one member selected from pentaerythritol tri (meth) acrylate, ethylene oxide and propylene oxide modified by a species selected from the group consisting of pentaerythritol tetra (meth) acrylate, ethylene oxide and propylene oxide Varied by species The dipentaerythritol, and the like erythritol penta (meth) acrylate, and ethylene oxide-modified by means of at least one member selected from propylene oxide, dipentaerythritol hexa (meth) acrylate.

Examples of the compound having two or more N-alkoxymethylamino groups include compounds having a melamine structure, a benzoguanamine structure or a urea structure. Further, the melamine structure or benzoguanamine structure refers to a chemical structure having at least one triazine ring or phenyl-substituted triazine ring as a basic skeleton, and also includes melamine, benzoguanamine or a condensate thereof. Specific examples of the compound having two or more N-alkoxymethylamino groups include N, N, N ', N', N '', N '' - hexa (alkoxymethyl) Tetra (alkoxymethyl) benzoguanamine, N, N, N ', N'-tetra (alkoxymethyl) glycoluril and the like.

(Meth) acrylate, caprolactone-modified polyfunctional (meth) acrylate, and polyfunctional urethane obtained by reacting (C) a polymerizable compound with an aliphatic polyhydroxy compound having three or more valences with (meth) (Alkoxymethyl) melamine and N, N, N ', N'-tetra (alkoxymethyl) benzoguanamine are preferable Do. Among the multifunctional (meth) acrylates obtained by reacting a trivalent or higher aliphatic polyhydroxy compound with (meth) acrylic acid, trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, Erythritol pentaacrylate and dipentaerythritol hexaacrylate are excellent in the strength of the cured film and excellent in surface smoothness of the cured film and in that it is difficult to generate scum and residual film on the substrate of the unexposed portion and on the light shielding layer Particularly preferred.

The polymerizable compound (C) may contain a Si atom or a F atom, particularly preferably an F atom. By including such an atom, the polymerizable compound (C) is provided with a liquid repellency property. As a result, it becomes easy to apply a composition for forming a color filter or a composition for forming a phosphor layer or the like between the cured films formed by the present composition, and it becomes easy to form a display device having high functionality by using the cured film as a partition wall.

As the (C) polymerizable compound containing F atom, for example, there may be mentioned a compound in which part or all of the hydrogen atoms of the hydrocarbon group of the polyfunctional (meth) acrylate are substituted with F atoms, polyfunctional (Meth) acrylate, and the like. Examples of the (C) polymerizable compound containing Si atom include polyfunctional (meth) acrylates having a structure such as silyl group, polyalkylsiloxane, silsesquioxane and the like. In addition, a polysiloxane having a plurality of polymerizable groups such as an oxiranyl group and an oxetanyl group may be used.

The content of the polymerizable compound (C) is usually 3 to 200 parts by mass, preferably 5 to 100 parts by mass, and more preferably 10 to 50 parts by mass based on 100 parts by mass of the total of (A) the white pigment. The content of the polymerizable compound (C) is usually 20 to 300 parts by mass, preferably 30 to 250 parts by mass, and more preferably 50 to 200 parts by mass based on 100 parts by mass of the (B) alkali-soluble resin. By adopting this form, a cured film having excellent heat resistance and chemical resistance can be formed.

<(D) Photopolymerization initiator>

(D) The photopolymerization initiator is a compound which generates active species capable of initiating polymerization of the polymerizable compound (C) by exposure to radiation such as visible light, ultraviolet light, deep ultraviolet light, electron beam, and X-ray. The photopolymerization initiator may be used alone or in combination of two or more.

Examples of such a photopolymerization initiator (D) include a thioxanone compound, an acetophenone compound, a nonimidazole compound, a triazine compound, an O-acyloxime compound, an onium salt compound, a benzoin compound, Compounds, acylphosphine oxide compounds, titanocene compounds,? -Diketone compounds, polynuclear quinone compounds, diazo compounds, imidosulfonate compounds, and onium salt compounds. Among them, at least one member selected from an O-acyloxime compound, an acetophenone compound, an acylphosphine oxide compound and a titanocene compound is preferable.

Examples of the O-acyloxime compound include 1,2-octanedione, 1- [4- (phenylthio) phenyl] -, 2- (O-benzoyloxime), ethanone, 1- [ 1- (9-ethyl-6- (2-methyl-4-tetrahydro-naphthalen- Yl) -, 1- (O-acetyloxime), ethanone, 1- [9-ethyl-6- { Dimethyl-1,3-dioxolanyl) methoxybenzoyl} -9H-carbazol-3-yl] -, 1- (O- acetyloxime) Ethyl] -9H-carbazol-9-yl] phenyl, 1 - [(acetyloxy) - (O-acetyloxime), and the like. DFI-020, DFI-091 (manufactured by Daito Kikusui K. K.), IrgacureOXE-03, NCI-930 (commercially available from ADEKA) IrgacureOXE-04 (manufactured by BASF Co., Ltd.) or the like may be used.

Among these O-acyloxime compounds, ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol- Methylbenzoyl] -6- [1 - [(acetyloxy) imino] ethyl] - [4- 9H-carbazol] -9-yl] phenyl, 1- (O-acetyloxime).

As the acetophenone compound, an? -Aminoalkylphenone compound is more preferable, and for example, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane- 2- (dimethylamino) -1- (4-morpholinophenyl) butane-1-one, 2- 1-on.

Among these acetophenone compounds, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1-one and 2-benzyl- Naphthyl) butan-1-one is preferred.

Examples of the acylphosphine oxide-based compound include isobutyrylmethylphosphinic acid methyl ester, isobutyrylphenylphosphinic acid methyl ester, pivaloylphenylphosphinic acid methyl ester, 2-ethylhexanoylphenylphosphinic acid methyl ester, P-toluylphenylphosphinic acid methyl ester, o-toluylphenylphosphinic acid methyl ester, 2,4-dimethylbenzoylphenylphosphinic acid methyl ester, pt-butylbenzoylphenylphosphinic acid Isopropylidene diphenylphosphine oxide, o-toluyldiphenylphosphine oxide, pt-butylbenzoyldiphenylphosphine oxide, isobutyryldiphenylphosphine oxide, 2-ethylhexanoyldiphenylphosphine oxide, , 3-pyridylcarbonyldiphenylphosphine oxide, acryloyl-diphenylphosphine oxide, benzoyldiphenylphosphine oxide, pivaloylphenylphosphinic acid vinyl ester , Adipoylbis diphenylphosphine oxide, pivaloyldiphenylphosphine oxide, p-toluyldiphenylphosphine oxide, 4- (t-butyl) benzoyldiphenylphosphine oxide, terephthaloylbisdiphenylphosphine oxide , 2-methylbenzoyldiphenylphosphine oxide, versatoyldiphenylphosphine oxide, 2-methyl-2-ethylhexanoyldiphenylphosphine oxide, 1-methyl-cyclohexanoyldiphenylphosphine oxide, pivaloyl Monoacylphosphine oxides such as phenylphosphinic acid methyl ester, pivaloylphenylphosphinic acid isopropyl ester, and 2,4,6-trimethylbenzoyldiphenylphosphine oxide; Bis (2,6-dichlorobenzoyl) phenylphosphine oxide, bis (2,6-dichlorobenzoyl) -2,5-dimethylphenylphosphine oxide, bis (2,6- (2,6-dichlorobenzoyl) -4-propylphenylphosphine oxide, bis (2,6-dichlorobenzoyl) -2-naphthylphosphine oxide, bis (2,6- Bis (2,6-dichlorobenzoyl) -4-chlorophenylphosphine oxide, bis (2,6-dichlorobenzoyl) -2,4-dimethoxyphenylphosphine oxide, bis (2,6-dichlorobenzoyl) -4-octylphenylphosphine oxide, bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, bis (2,4,6- Dimethylphenylphosphine oxide, bis (2,6-dichloro-3,4,5-trimethoxybenzoyl) -2,5-dimethylphenylphosphine oxide, bis - Dichloro-3,4,5-trimethoxybenzo ) -4-ethoxyphenylphosphine oxide, bis (2-methyl-1-naphthoyl) -2,5-dimethylphenylphosphine oxide, bis Bis (2-methyl-1-naphthoyl) -4-propylphenylphosphine oxide, bis (2- (1-naphthoyl) -2,5-dimethylphenylphosphine oxide, bis (2-methoxy-1-naphthoyl) -4-ethoxyphenylphosphine oxide, bis Bisacylphosphine oxides such as 2,5-dimethylphenylphosphine oxide and bis (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide; And the like. In addition, acylphosphine compounds described in JP-A-3-101686, JP-A-5-345790 and JP-A-6-298818 may be used.

Among these acylphosphine oxide-based compounds, 2,4,6-trimethylbenzoyldiphenylphosphine oxide (for example, Darocur TPO, manufactured by BASF) is preferred as the monoacylphosphine oxide, and bis , 4,6-trimethylbenzoyl) phenylphosphine oxide (for example, BASF, Irgacure 819) and bis (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphenylphosphine oxide Irgacure 1700), and bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide is more preferable.

Examples of the titanocene-based optical compound include bis (cyclopentadienyl) -Ti-di-chloride, bis (cyclopentadienyl) -Ti-bis-phenyl, bis (cyclopentadienyl) , 3,4,5,6-pentafluorophenyl, bis (cyclopentadienyl) -Ti-bis-2,3,5,6-tetrafluorophenyl, bis (cyclopentadienyl) Bis (cyclopentadienyl) -Ti-bis-2,6-difluorophenyl, bis (cyclopentadienyl) -Ti-bis-2,4-di Bis (methylcyclopentadienyl) -Ti-bis-2,3,4,5,6-pentafluorophenyl, bis (methylcyclopentadienyl) -Ti-bis-2,3,5 Bis (cyclopentadienyl) -bis (methylcyclopentadienyl) -Ti-bis-2,6-difluorophenyl (for example, manufactured by BASF, Irgacure 727L) (2,4,6-trichlorophenyl) titanium (for example, Irgacure 784 manufactured by BASF), bis (cyclopentadienyl) -bis (2,4,6- (Cyclopentadienyl) -bis (2,4,6-trifluoro-3- (2-5-dimethylpyr-l- Yl) phenyl) titanium, and the like.

Among these titanocene compounds, bis (cyclopentadienyl) -bis (2,6-difluoro-3- (pyr-1-yl) phenyl) titanium is preferable.

Examples of the photopolymerization initiator (D) other than the above include those exemplified in, for example, paragraphs [0079] to [0095] of JP-A No. 2010-134419.

Among them, the photopolymerization initiator (D) preferably contains at least one selected from an O-acyloxime compound, an acylphosphine oxide compound and a titanocene compound. O-acyloxime compound, acylphosphine oxide compound and titanocene compound, the content thereof is preferably 90% by mass or more, particularly preferably 96% by mass or more, of the total photopolymerization initiator.

The content of the photopolymerization initiator (D) is usually 1 to 100 parts by mass, preferably 3 to 70 parts by mass, and more preferably 5 to 50 parts by mass based on 100 parts by mass of the (C) polymerizable compound. By adopting this form, it is possible to form a cured film excellent in heat resistance, chemical resistance, curability and the like.

<(E) Solvent>

The composition contains the above components (A) to (D) and optionally other components, but is usually prepared as a liquid composition by blending (E) a solvent such as an organic solvent.

The solvent (E) may be appropriately selected and used as long as it dissolves or dissolves the components (A) to (D) and other components constituting the composition and does not react with these components and has appropriate volatility.

Examples of the organic solvent include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n-propyl ether, ethylene glycol mono-n-butyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether Diethylene glycol mono-n-propyl ether, diethylene glycol mono-n-butyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono propyl ether, dipropylene glycol mono-n-butyl ether, dipropylene glycol mono-n-butyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol mono- Propylene glycol monomethyl ether, and tripropylene glycol monoethyl ether; Call monoalkyl ether; Lactic acid alkyl esters such as methyl lactate and ethyl lactate; (Cyclo) alkyl alcohols such as methanol, ethanol, propanol, butanol, isopropanol, isobutanol, t-butanol, octanol, 2-ethylhexanol and cyclohexanol; Ketoalcohols such as diacetone alcohol; Ethylene glycol monomethyl ether acetate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate (hereinafter abbreviated as PGMEA), propylene glycol monoethyl ether (Poly) alkylene glycol monoalkyl ether acetates such as acetate, dipropylene glycol monomethyl ether acetate, 3-methoxybutyl acetate and 3-methyl-3-methoxybutyl acetate; Glycol ethers such as diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol diethyl ether, and tetrahydrofuran; Ketones such as methyl ethyl ketone, cyclohexanone, 2-heptanone and 3-heptanone; Diacetates such as propylene glycol diacetate, 1,3-butylene glycol diacetate and 1,6-hexanediol diacetate; Alkoxycarboxylates such as methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, ethyl ethoxyacetate and 3-methyl- Acid esters; Amyl acetate, n-butyl acetate, ethyl butyrate, n-propyl butyrate, i-propyl butyrate, propyl acetate, isopropyl acetate, n- , Fatty acid alkyl esters such as n-butyl butyrate, methyl pyruvate, ethyl pyruvate, n-propyl pyruvate, methyl acetoacetate, ethyl acetoacetate, and ethyl 2-oxobutanoate; Aromatic hydrocarbons such as toluene and xylene; Amides such as N, N-dimethylformamide, N, N-dimethylacetamide and N-methylpyrrolidone, and lactam.

Among these organic solvents, (poly) alkylene glycol monoalkyl ether, lactic acid alkyl ester, (poly) alkylene glycol monoalkyl ether acetate, glycol ether, Ketones, diacetates, alkoxycarboxylic acid esters and fatty acid alkyl esters are preferable, and propylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether Acetate, 3-methoxybutyl acetate, diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, cyclohexanone, 2-heptanone, 3-heptanone, 1,3-butylene glycol diacetate, Hexanediol diacetate, ethyl lactate, ethyl 3-methoxypropionate, 3-ethoxypropionate, n-butyl acetate, It includes acid i- butyl, n- amyl formate, ethyl i- amyl propionate, n- butyl butyrate, ethyl butyrate, i- propyl butyrate, n- butyl, ethyl pyruvate, is preferred.

As the solvent (E), an inorganic solvent such as water may be used.

In the present composition, the (E) solvent may be used alone or as a mixture of two or more kinds thereof. The content of the solvent (E) is not particularly limited, but it is preferably such that the total concentration of all components except for the (E) solvent in the composition is 5 to 70 mass%, more preferably 10 to 60 mass% desirable. By using this form, the present composition having good coating properties and storage stability can be obtained.

<Dispersant>

The present composition may further comprise a dispersant. The dispersing agent is not particularly limited as far as it is a compound (A) that is capable of dispersing the white pigment well in the solvent (E).

Examples of the known dispersant include urethane-based dispersants, polyethyleneimine-based dispersants, polyoxyethylene alkyl ether-based dispersants, polyoxyethylene alkyl phenyl ether-based dispersants, polyethylene glycol diester dispersants, sorbitan fatty acid ester- Dispersants, (meth) acrylic dispersants, phosphoric acid ester dispersants and the like. (Meth) acrylic dispersant such as Disperbyk-2000, Disperbyk-2001, Disperbyk-182, Disperbyk-184, BYK-LPN6919 and BYK-LPN21116 (manufactured by BYK) Urethane dispersants such as Disperbyk-162, Disperbyk-165, Disperbyk-167, Disperbyk-170 and Disperbyk-182 (manufactured by BYK), Solpus 76500 (manufactured by Lubrizol Corporation) (Trade name, manufactured by Ajinomoto Fine Techno Co., Ltd.) such as AJISPER PB821, Ajisper PB822, Ajisper PB880 and Ajisper PB881 (manufactured by Ajinomoto Fine Techno Co., Ltd.) BYK-LPN21324 (manufactured by BYK) may be used in addition to a dispersant, a phosphate ester dispersant such as Disperbyk-110 and Disperbyk-180.

Among them, at least one kind selected from the group consisting of a (meth) acrylic dispersant, a phosphoric acid ester dispersant, a urethane dispersant and a polyester dispersant is preferable as the dispersant from the viewpoint of improvement of the storage stability, and a (meth) acrylic dispersant and a phosphate ester Based dispersing agent is more preferable.

The dispersant preferably has an acid value of 30 to 200 mgKOH / g or an amine value of 10 to 200 mgKOH / g from the viewpoint of improvement of storage stability. From the viewpoint of dispersibility of the (A) white pigment, the acid value is more preferably from 40 to 100 mg KOH / g, and the amine value is more preferably from 20 to 180 mg KOH / g. Here, &quot; amine value &quot; means the number of mg of KOH equivalent to HCl required to neutralize 1 g of solid content.

The dispersants may be used alone or in combination of two or more. (Meth) acrylic dispersant is preferably contained in an amount of not less than 50% by mass, more preferably not less than 70% by mass based on the total amount of the dispersing agent, desirable. By using this form, it becomes easy to obtain the present composition which is more excellent in storage stability.

The content of the dispersant is usually 0.5 to 50 parts by mass, preferably 2 to 30 parts by mass, per 100 parts by mass of the (A) white pigment. By using this form, the present composition having excellent storage stability can be formed.

The present composition preferably contains (B) an alkali-soluble resin and a dispersant as a component serving as a binder. The total content of the alkali-soluble resin (B) and the dispersant is preferably 2 to 150 parts by mass, more preferably 10 to 70 parts by mass, per 100 parts by mass of the total amount of (A) the white pigment.

&Lt; (F) Surfactant >

The composition may further comprise (F) a surfactant. (F) a surfactant can be used to increase the film formability of the composition and to improve the surface smoothness of the resulting coating film. As a result, the uniformity of the film thickness of the resulting cured film can be further improved.

The surfactant (F) may contain a Si atom or a F atom. Specifically, the surfactant may include a compound described in JP-A-2003-015278 and JP-A-2013-231869. By including such an atom, (F) the surfactant is imparted with lyophobicity. As a result, it becomes easy to apply a composition for forming a color filter or a composition for forming a phosphor layer, etc. between the cured film formed by the composition, and it becomes easy to form a display device having high functionality by using the cured film as a partition .

When the surfactant (F) is used, the content thereof in the present composition is preferably 20 parts by mass or less, more preferably 0.01 to 15 parts by mass, and still more preferably 0.01 parts by mass or less, per 100 parts by mass of the alkali-soluble resin (B) 0.05 to 10 parts by mass. When the content of the (F) surfactant is within the above range, the uniformity of the film thickness of the formed coating film can be further improved.

The present composition further contains (F) a surfactant, and at least one member selected from the group consisting of (B) an alkali-soluble resin, (C) a polymerizable compound and (F) It is preferred that F atoms are included.

<Additives>

The present composition may contain various additives as required. Examples of the additive include fillers such as glass and alumina; High molecular compounds such as polyvinyl alcohol and poly (fluoroalkyl acrylate); Vinyltriethoxysilane, vinyltris (2-methoxyethoxy) silane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, N- (2-aminoethyl) Aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3,4-epoxycyclo Hexyl) ethyltrimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropyltrimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane and the like Adhesion promoters such as silane coupling agents; Di-t-butylphenol, pentaerythritol tetrakis [3- (3,5-di-t-butyl-4 (3-t-butyl-4-hydroxy-5-methylphenyl) propionyl] -1,1-dimethylethyl] (4,5-di-t-butyl-4-hydroxyphenyl) propionate], tris 2,4-di-t-butylphenyl) phosphite; Ultraviolet absorbers such as 2- (3-t-butyl-5-methyl-2-hydroxyphenyl) -5-chlorobenzotriazole and alkoxybenzophenones; An anti-aggregation agent such as sodium polyacrylate; Amino-1-pentanol, 3-amino-1,2-propane, 3-amino-1-pentanol, Diol, 2-amino-1,3-propanediol, 4-amino-1,2-butanediol and the like; A developing agent such as succinic acid mono [2- (meth) acryloyloxyethyl] phthalate mono [2- (meth) acryloyloxyethyl], omega -carboxylic polycaprolactone mono (meth) . Further, it is assumed that the adhesion promoter does not correspond to the polymerizable compound (C).

Among these additives, the content of the adhesion promoter such as a silane coupling agent is preferably 1 to 20 parts by mass, more preferably 3 to 15 parts by mass, per 100 parts by mass of the (B) alkali-soluble resin. The content of the antioxidant is preferably 0.1 to 10 parts by mass, more preferably 1 to 5 parts by mass, per 100 parts by mass of the alkali-soluble resin (B). The content of the total of the additives (components (A) to (F) and components other than the dispersant) in the composition is preferably 1 to 20 parts by mass relative to 100 parts by mass of the alkali-soluble resin (B) 15 parts by mass may be more preferable. When the content of the additive is within the above range, the effect of adding the additive together with the effect of the present invention can be sufficiently exhibited.

The present composition can be produced by a suitable method, and the preparation method thereof can be produced, for example, by mixing the components (A) to (D) together with (E) a solvent or other components to be optionally added. Among them, (A) a white pigment is mixed and dispersed in a solvent (E) in the presence of a dispersing agent, optionally by grinding with a part of the alkali-soluble resin (B) using, for example, a bead mill or a roll mill (C) a polymerizable compound, (B) an alkali-soluble resin, (D) a photopolymerization initiator, (E) a solvent and other components are added to the white pigment dispersion, Hereinafter also referred to as production method I).

The colorant different from (A) the white pigment and (A) the white pigment is dissolved in the solvent (E) in the presence of a dispersing agent, if necessary together with part of the alkali-soluble resin (B) (B) an alkali-soluble resin, (D) a photopolymerization initiator, (E) a solvent, and (B) an alkali-soluble resin. The white pigment dispersion is prepared by mixing and dispersing the above- (Hereinafter, also referred to as &quot; production method II &quot;) may be employed. The white pigment dispersion in Production Method II can be subjected to a step of uniformly dispersing the coloring agent different from (A) the white pigment and (A) the white pigment simultaneously in the (E) solvent. The white pigment dispersion in Production Method II contains at least a colorant different from (A) a white pigment and (A) a white pigment, (B) an alkali-soluble resin and (E) (A) a colorant different from (A) the white pigment and (A) the white pigment is uniformly dispersed even when the content of (A) is 80 parts by mass or less, particularly 60 parts by mass or less and furthermore 45 parts by mass or less based on 100 parts by mass of the white pigment. And a white pigment dispersion having excellent storage stability can be obtained. Production method II is useful when (A) the coloring agent different from the white pigment is a poorly soluble or insoluble compound in the (E) solvent such as a pigment.

The production method II can also be carried out with reference to the methods described in, for example, Japanese Patent Application Laid-Open No. 2001-108817 and Japanese Patent Laid-Open Publication No. 2013-205832.

&Lt; Cured film and display element, and method for manufacturing the same &

The cured film according to one embodiment of the present invention comprises (A) a white pigment, wherein (A) the white pigment is contained in an amount of 30 to 90% by mass based on 100% by mass of the total solid content. The cured film according to one embodiment of the present invention can be specifically formed by using the present composition. Further, the display element according to one embodiment of the present invention includes the cured film of the present invention as a partition wall. The barrier ribs provided in the display element may be referred to as a bank, a matrix, or the like.

Hereinafter, a method of forming a cured film used for a partition wall constituting a display element will be described. First, after the liquid composition of the present composition is applied on the surface of the substrate, pre-baking is performed and the solvent is evaporated to form a coating film. Subsequently, this coating film is exposed through a photomask, and then developed with an alkali developing solution to dissolve and remove the unexposed portion of the coating film. Thereafter, the cured film is formed in a predetermined arrangement by post-baking.

Examples of the substrate used for forming the cured film include glass, silicon, polycarbonate, polyester, aromatic polyamide, polyamideimide, and polyimide.

These substrates may be subjected to appropriate pretreatment such as chemical treatment with a silane coupling agent or the like, plasma treatment, ion plating, sputtering, vapor phase reaction, vacuum deposition or the like depending on the purpose.

When the composition is applied to a substrate, a suitable coating method such as a spraying method, a roll coating method, a spin coating method (spin coating method), a slit die coating method (slit coating method), or a bar coating method can be employed, A spin coating method, and a slit die coating method.

The pre-baking is usually carried out in combination with reduced-pressure drying and heat drying. The reduced-pressure drying is usually carried out until 50 to 200 Pa is reached. The conditions for heating and drying are usually about 70 to 110 DEG C for about 1 to 10 minutes.

The coating thickness is usually from 1 to 100 μm, preferably from 2 to 30 μm, more preferably from 5 to 20 μm, as a film thickness after drying.

Examples of the light source of radiation used when forming the cured film include a lamp light source such as a xenon lamp, a halogen lamp, a tungsten lamp, a high pressure mercury lamp, an ultra high pressure mercury lamp, a metal halide lamp, a medium pressure mercury lamp or a low pressure mercury lamp, , A XeCl excimer laser, a nitrogen laser, and the like. As an exposure light source, an ultraviolet LED may be used. The wavelength is preferably in the range of 190 to 450 nm.

When the cured film formed by the above method is used as a partition wall of a display device, it is preferable that a cured film formed by dispersing a pigment or the like in an organic solvent, such as a composition for forming a color filter or a phosphor layer between partition walls or a composition for forming a phosphor layer And is preferably lyophobic in view of easy application of the composition.

Here, the liquid repellency refers to the liquid repellency, which is determined by measuring the static contact angle with respect to the PGMEA on the surface of the cured film using a contact angle meter (automatic contact angle meter CA-V150 manufactured by Kyowa Kaimen Kagaku Kabushiki Kaisha) °, more preferably 15 ° or more, and still more preferably 30 ° or more. On the other hand, the upper limit of the static contact angle is, for example, 90 degrees.

The exposure dose of the radiation is generally preferably from 10 to 10,000 J / m ² .

Examples of the alkali developer include sodium carbonate, sodium hydrogencarbonate, sodium hydroxide, potassium hydroxide, tetramethylammonium hydroxide, choline, 1,8-diazabicyclo- [5.4.0] 1,5-diazabicyclo- [4.3.0] -5-nonene and the like are preferable.

A water-soluble organic solvent such as methanol or ethanol, a surfactant, etc. may be added in an appropriate amount to the alkali developing solution. After the alkali development, it is usually washed with water.

As the development processing method, a shower development method, a spray development method, a dip (immersion) development method, a puddle (liquid immersion) development method, or the like can be applied. The developing conditions are preferably 5 to 300 seconds at room temperature.

The post-baking conditions are usually about 120 to 300 DEG C for about 10 to 90 minutes. The composition of the present invention can form a cured film having a low yellowing even when the post-baking temperature is 180 to 300 占 폚, 230 to 290 占 폚, and 250 to 280 占 폚.

The thickness of the cured film thus formed is usually 1 to 100 占 퐉, preferably 2 to 30 占 퐉, and more preferably 5 to 20 占 퐉.

The shape of the cured film may be a shape having a net taper, a shape having a vertical taper, a shape having a reverse taper, or a shape having a substantially circular shape. Here, the shape having a net taper refers to a shape in which the cured film becomes smaller toward the substrate with respect to the substrate, and the shape having a vertical taper refers to a shape in which the cured film is substantially constant upward with respect to the substrate, Refers to a shape in which the cured film grows upward toward the substrate. In the case where the cured film has the above-described tapered shape, the taper angle is preferably 50 to 130 DEG, more preferably 60 to 120 DEG.

The cured film formed from this composition has a low percentage of light transmittance because of a high content of white pigment. The lower limit of the optical density (OD) of the cured film is preferably 0.05 / 占 퐉, more preferably 0.1 / 占 퐉, and further preferably 0.2 / 占 퐉. On the other hand, the upper limit of the optical density (OD) is preferably 5.0 / 占 퐉.

A transparent conductive film can be formed on the cured film thus obtained by sputtering or a protective film can be formed if necessary. This composition is useful from the viewpoint of reliability as a partition wall used in a display element when the yellowing is small even if the composition is subjected to heat treatment at 250 占 폚 or more at the time of forming transparent electrodes.

Further, in recent years, there has been a case where a color filter or a phosphor layer is provided between the barrier ribs from the request of high functionality of the display element. For example, in an organic EL element or a micro LED element which is an example of a display element, a color filter or a phosphor layer is provided between partition walls. In a micro LED device, a micro LED is usually disposed between the partition walls. Here, when a cured film having high liquid repellency, which is a form of the present invention, is used as the barrier rib of the display element, a composition for forming a color filter or a phosphor layer, a composition for forming a phosphor layer, As a result, a display device having high functionality can be easily manufactured.

The method of applying the composition for forming a color filter or the composition for forming a phosphor layer between the partition walls having high lyophobicity can be carried out by a known method. Specific examples of the method include a coating method using a brush or a brush, a dipping method, a spraying method, a roll coating method, a rotary coating method (spin coating method), a slit die coating method, a bar coating method, a flexographic printing, , Inkjet printing, and dispensing method. Of these, the dipping method, the spraying method, the spin coating method, the slit die coating method, the offset printing method, the screen printing method, the ink jet method and the dispensing method are preferable, and the ink jet method is particularly preferable.

The inkjet method has a small amount of defective discharge of the composition to be applied and has industrially excellent properties, but there is also a possibility that an ink droplet may be deposited at a desired point. However, when the partition wall having a high lyophobicity is used, the ink droplet is hardly left on the top of the partition wall head, and the ink droplet that has been coated easily enters the inside of the partition wall, resulting in a good pattern of the coating. Therefore, when a cured film having high lyophobicity, which is a form of the present invention, is used for a partition wall of a display element, by applying a composition for forming a color filter or a composition for forming a phosphor layer, etc. by an inkjet method, It is possible to suppress the ink adhesion and to form a desired color filter, a pattern of a phosphor layer, or the like.

The display element in which the cured film of the present invention is used for the partition of the display element has a high light extraction function due to high reflection characteristics and ease of forming a functional layer between the partition walls. Such a display element is suitably used in an organic EL element or a micro LED element in which miniaturization between partition walls is particularly required.

[Example]

Hereinafter, the present invention will be described more specifically by way of examples. However, the present invention is not limited to the following examples. Further, in the following synthesis examples, it can be considered that the charging ratio (mass ratio) of each monomer and the content ratio (mass ratio) of the structural units corresponding to each monomer in the obtained resin are substantially the same.

<Synthesis of alkali-soluble resin>

[Synthesis Example 1] (B-1) Synthesis of alkali-soluble resin

After the inside of the flask was purged with nitrogen, 250 parts by mass of a PGMEA solution obtained by dissolving 8 parts by mass of 2,2'-azobis (2,4-dimethylvaleronitrile) was added thereto. Subsequently, 20 parts by mass of methacrylic acid (hereinafter abbreviated as MA) as a monomer and 80 parts by mass of methyl methacrylate (hereinafter abbreviated as MMA) were added, and stirring was started slowly. The temperature of the solution was raised to 70 캜 and maintained at this temperature for 5 hours. Thereafter, the reaction product solution was added dropwise to a large amount of methanol to solidify the reaction product. After washing the solidified product with water, the residue was redissolved in 200 g of tetrahydrofuran and solidified again with a large amount of methanol to obtain an alkali-soluble resin (B-1). The Mw of the obtained alkali-soluble resin (B-1) was 9,500.

[Synthesis Example 2] (B-2) Synthesis of alkali-soluble resin

Except that 10 mass parts of 1H, 1H, 2H, 2H-tridecafluorooctyl methacrylate (hereinafter abbreviated as F-containing acrylate), 10 mass parts of MA and 80 mass parts of MMA were used as monomers, Similarly, (B-2) an alkali-soluble resin was synthesized. The Mw of the obtained alkali-soluble resin (B-2) was 8,900.

[Synthesis Example 3] (B-3) Synthesis of alkali-soluble resin

An alkali-soluble resin (B-3) was synthesized in the same manner as in Synthesis Example 1 except that 30 parts by mass of F-containing acrylate, 10 parts by mass of MA and 60 parts by mass of MMA were used as monomers. The Mw of the obtained (B-3) alkali-soluble resin was 8,200.

[Synthesis Example 4] (B-4) Synthesis of alkali-soluble resin

An alkali-soluble resin (B-4) was synthesized in the same manner as in Synthesis Example 1 except that 40 parts by mass of glycidyl methacrylate (hereinafter abbreviated as GMA), 20 parts by mass of MA and 40 parts by mass of MMA were used as monomers . The Mw of the obtained (B-4) alkali-soluble resin was 9,800.

[Synthetic Example 5] (B-5) Synthesis of alkali-soluble resin

As in Synthesis Example 1, except that 40 parts by mass of GMA, 20 parts by mass of MA, 22 parts by mass of N-phenylmaleimide (hereinafter abbreviated as PMI) and 18 parts by mass of styrene (hereinafter abbreviated as St) (B-5), an alkali-soluble resin was synthesized. The Mw of the obtained alkali-soluble resin (B-5) was 8,800.

[Synthesis Example 6] (B-6) Synthesis of alkali-soluble resin

An alkali-soluble resin (B-6) was synthesized in the same manner as in Synthesis Example 1, except that 30 parts by mass of F-containing acrylate, 35 parts by mass of GMA, 7 parts by mass of MA and 28 parts by mass of MMA were used as monomers. The Mw of the obtained alkali-soluble resin (B-6) was 7,800.

[Synthesis Example 7] (B-7) Synthesis of alkali-soluble resin

Except that 30 parts by mass of F-containing acrylate, 35 parts by mass of GMA, 7 parts by mass of MA, 16 parts by mass of PMI and 12 parts by mass of 4-isopropenylphenol (hereinafter abbreviated as Hs) Similarly, (B-7) an alkali-soluble resin was synthesized. The Mw of the obtained (B-7) alkali-soluble resin was 8,100.

[Synthesis Example 8] (B-8) Synthesis of a non-alkali-soluble resin

An alkali-soluble resin (B-8) was synthesized in the same manner as in Synthesis Example 1 except that 60 parts by mass of GMA, 22 parts by mass of PMI and 18 parts by mass of St were used as monomers. The Mw of the obtained (B-8) non-alkali soluble resin was 9,800.

&Lt; Evaluation of particle size distribution diameter &

The white pigment dispersion prepared below was diluted 10-fold with PGMEA and the average particle diameter of the white pigment (A) was determined using a particle size analyzer (L-500, manufactured by HORIBA).

&Lt; Preparation of white pigment dispersion >

[Production Example 1]

90 parts by mass of CI Pigment White 6: 1 (titanium oxide) surface modified with alumina and siloxane, BYK-LPN21116 (trade name, BYK), acrylic dispersion agent with an amine value of 29 mgKOH / g, (A-1) white pigment dispersion was prepared by mixing 25 parts by mass of polyvinyl alcohol and 25 parts by mass of PGMEA as a dispersion medium so as to have a solid content concentration of 50 mass% for 12 hours using a bead mill. The average particle diameter of the white pigment in the obtained white pigment dispersion (A-1) was 280 nm.

&Lt; Preparation and evaluation of curable composition >

[Example 1]

(B) an alkali-soluble resin (B-1) as an alkali-soluble resin, (C) 100 parts by mass of an alkali-soluble resin (C) as a polymerizable compound, KAYARAD DPHA (A mixture of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate, manufactured by Nippon Kayaku Co., Ltd.), 10 parts by mass of (D) NCI-930 (manufactured by ADEKA K.K.) as a photopolymerization initiator, 0.5 parts by mass of F-554 (manufactured by DIC Corporation) as the surfactant (F), 3 parts by mass of 3-glycidoxypropyltrimethoxysilane (KBM (trade name) manufactured by Shinetsu Kagaku K. K.) as a silane coupling agent , 3 parts by mass of pentaerythritol tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate (Irganox1010 manufactured by BASF) as an antioxidant, (E) PGMEA as a solvent was mixed so as to have a solid content concentration of 50 mass%, and (S-1) Here a photosensitive composition was prepared for forming.

&Lt; Preparation of cured film for evaluation of optical density (OD), reflectance and lyophobicity >

(S-1) The photosensitive composition for forming a display element was coated on a soda glass substrate using a spin coater and then pre-baked at 90 占 폚 for 2 minutes on a hot plate to form a coating film having a thickness of 12 占 퐉. Subsequently, using a high-pressure mercury lamp, the coating film was exposed to radiation including wavelengths of 365 nm, 405 nm, and 436 nm at an exposure dose of ²⁰⁰ J / m ² without passing through the photomask. Thereafter, a shower phenomenon was carried out by discharging a 0.04% aqueous solution of potassium hydroxide at 23 DEG C at a developing pressure of 1 kgf / cm &lt; ² &gt; (nozzle diameter of 1 mm), and then subjected to post-baking at 230 DEG C for one hour to form a film thickness Thereby forming a 10 탆 cured film.

&Lt; Preparation of a cured film for evaluation of pattern formability and heat resistance &

(S-1) The photosensitive composition for forming a display element was coated on a soda glass substrate using a spin coater and then pre-baked at 90 占 폚 for 2 minutes on a hot plate to form a coating film having a thickness of 12 占 퐉. Subsequently, using a high-pressure mercury lamp, the coating film was exposed to radiation including wavelengths of 365 nm, 405 nm, and 436 nm at an exposure dose of 50 J / m ² using a photomask of L / S = 10 탆 / 30 탆. Thereafter, a shower phenomenon was carried out by discharging a 0.04% aqueous solution of potassium hydroxide at 23 DEG C at a developing pressure of 1 kgf / cm &lt; ² &gt; (nozzle diameter of 1 mm), and then subjected to post-baking at 230 DEG C for one hour to form a film thickness And a cured film having an aspect ratio of 0.8 (film thickness / line width) was formed.

[Examples 2 to 13 and Comparative Examples 1 to 3]

Each composition was prepared in the same manner as in Example 1, except that the kinds and mixing amounts of the respective components were changed as shown in Table 1. Further, a cured film was formed in the same manner as in (S-1) the photosensitive element for forming a display element of Example 1.

<Evaluation>

[Optical density (OD)]

Optical density (OD) of the cured film for evaluation was measured using an optical densitometer (LCF1100A, manufactured by Otsuka Denshi Co., Ltd.). A &quot;, a case where OD is less than 0.1 / 占 퐉 and a case where OD is less than 0.05 / 占 퐉 is defined as &quot;Quot; C &quot;. The evaluation results are shown in Table 1.

[reflectivity]

The reflectance (light reflectance) in the wavelength range of 340 to 700 nm of the cured film for evaluation was measured from the substrate side using a spectral reflectance measuring apparatus (CM-700D, manufactured by Konica Minolta). "A" represents the case where the reflectance is 60% or more, "A" represents the case where the reflectance is less than 60%, "B" when the reflectance is less than 40%, and "C" when the reflectance is less than 20%. The evaluation results are shown in Table 1.

[Pattern Formability]

Whether or not the unexposed portion of the cured film for evaluation was completely dissolved was visually confirmed. A &quot; when dissolution was confirmed, and &quot; C &quot; when no dissolution was confirmed. The evaluation results are shown in Table 1.

[Repellency]

The static contact angle of the PGMEA on the cured film for evaluation was measured using a contact angle meter (automatic contact angle meter CA-V150, manufactured by Kyowa Chemical Industry Co., Ltd.), and the liquid repellency was evaluated. A "when the contact angle is 30 ° or more and 90 ° or less is defined as" A ", 15 ° or more and less than 30 ° are referred to as" A " Deg.] Was evaluated as &quot; C &quot;. The evaluation results are shown in Table 1.

[Heat resistance evaluation]

The cured film for evaluation was baked at 270 캜 for one hour, and the shape change was visually confirmed. Quot; A &quot; when the shape change was hardly confirmed, &quot; B &quot; when the shape change was confirmed, and &quot; C &quot; when the shape change was largely confirmed. The evaluation results are shown in Table 1.

As shown in Table 1, when the respective compositions of Examples 1 to 13 were used, a cured film having a high optical density (OD) and high reflectance was obtained, and pattern formation was good. That is, according to each of the compositions of Examples 1 to 12, it was found that a cured film compatible with a high light reflection function and a fine pattern shape could be formed.

The photosensitive composition for forming a display element can be used as a material for forming constituent members of a display element and can be particularly suitably used as a material for forming barrier ribs for organic EL elements and micro LED elements.

Claims (13)

(A) a white pigment,
(B) an alkali-soluble resin,
(C) a polymerizable compound,
(D) a photopolymerization initiator, and
(E) Solvent
Wherein the photosensitive composition is a photosensitive composition for forming a display element,
Wherein the content of the white pigment (A) is 30 to 90% by mass based on 100% by mass of all components excluding the solvent (E). The composition according to claim 1, further comprising (F) a surfactant,
(B) an alkali-soluble resin, (C) a polymerizable compound, and (F) a surfactant includes Si atoms or F atoms. The photosensitive composition for forming a display element according to claim 1 or 2, wherein the alkali-soluble resin (B) contains Si atoms or F atoms. The photosensitive composition for forming a display element according to claim 3, wherein the alkali-soluble resin (B) contains a group represented by the following formula (1).

(In the formula (1), R ¹ and R ² are each independently a hydrogen atom or a fluorine atom, A is an ester bond or an ether bond, and n is an integer of 1 to 10. When n is 2 or more, ¹ may be the same or different and a plurality of R ² may be the same or different. The positive resist composition according to claim 4, wherein the alkali-soluble resin (B) contains a structural unit having a group represented by the formula (1)
Wherein the content of the structural unit is 1 to 70% by mass with respect to 100% by mass of the alkali-soluble resin (B). The photosensitive composition for forming a display element according to any one of claims 1 to 5, wherein the alkali-soluble resin (B) comprises at least one member selected from the group consisting of a carboxyl group and a phenolic hydroxyl group. The positive resist composition according to any one of claims 1 to 6, wherein the alkali-soluble resin (B) contains at least one member selected from the group consisting of (meth) acryloyl groups, vinyl groups, oxiranyl groups and oxetanyl groups A photosensitive composition for forming a display element. The photosensitive composition for forming a display element according to any one of claims 1 to 7, wherein the alkali-soluble resin (B) contains a cyclic structure. 9. The process according to any one of claims 1 to 8, wherein (A) the white pigment is selected from the group consisting of alumina, magnesium oxide, antimony oxide, titanium oxide, zirconium oxide, aluminum hydroxide, magnesium hydroxide, barium sulfate, magnesium carbonate and barium carbonate And at least one kind of inorganic substance selected from the group consisting of the following. A cured film formed by using the photosensitive composition for forming a display element according to any one of claims 1 to 9. The cured film according to claim 10, wherein the optical density (OD) is 0.2 to 5.0 / 탆. The cured film according to claim 10 or 11, wherein the contact angle of the surface with respect to propylene glycol monomethyl ether acetate is 15 ° or more. An organic EL element having a partition or a display element which is a micro LED element,
Wherein the partition wall is the cured film according to any one of claims 10 to 12.