JP2019046790A - Photosensitive composition for display element formation, hardened film and display element - Google Patents

Abstract

To provide a photosensitive composition for display element formation, which is suitable for forming a hardened film and which enables the achievement of both of a high light-reflecting function and a fine pattern shape.SOLUTION: A photosensitive composition for display element formation comprises (A) a white pigment, (B) an alkali soluble resin, (C) a polymerizable compound, (D) a photoinitiator and (E) a solvent. Supposing that the total amount of compositions excluding the solvent (E) is 100 mass%, the content of the white pigment (A) is 30-90 mass%.SELECTED DRAWING: None

Description

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

  In the field of display panels, it is used in various applications by forming a fine pattern of resin on a substrate for display elements protected by a bezel or the like (panel edge) and giving characteristics to the pattern .

  For example, in the light emitting diode element, the above-described technique is used as a partition for partitioning to prevent color mixing of light (Patent Document 1). In addition, utilization as a partition wall for such color mixing suppression is the emission of light from organic electroluminescent devices (hereinafter abbreviated as organic EL devices), micro-sized light emitting diode devices (hereinafter abbreviated as micro LED devices), etc. With the miniaturization of the department, it has become a particularly sought after technology in recent years.

WO 2016/052025

  Although the partition which shows the outstanding characteristic is indicated in the above-mentioned patent documents 1, there is room for improvement in the taking-out function of the light radiated from a luminescence part, or the fabrication nature of a partition. That is, the partition described in Patent Document 1 is considered to suppress the color mixture of light by reflecting primary light and the like emitted from the LED chip by the white pigment contained in the partition. It is difficult to achieve both the reflection function and the formation of a fine barrier rib pattern containing a white pigment, and such a point is not described at all in Patent Document 1 above.

  The present invention has been made in view of the above, and provides a photosensitive composition for forming a display element which is suitable for forming a cured film which achieves both a high light reflection function and a fine pattern shape. is there.

  The present inventors diligently studied to solve the above problems. As a result, they have found that a composition having the following constitution is a suitable material for solving the above problems, and completed the present invention.

  That is, the embodiment of the present invention is a photosensitive device for forming a display element comprising (A) white pigment, (B) alkali soluble resin, (C) polymerizable compound, (D) photopolymerization initiator, and (E) solvent. Photosensitive composition, wherein the content of the (A) white pigment is 30 to 90 mass% when the total amount of components excluding the (E) solvent is 100 mass%. It is.

  Moreover, the aspect example of this invention is a display element which is a cured film formed using the said photosensitive composition for display element formation, and an organic EL element or micro LED element which has a partition, Comprising: The said partition is the said It is a display element which is a cured film.

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

<Photosensitive composition for forming display element>
A photosensitive composition for forming a display element according to an embodiment of the present invention (hereinafter referred to as the present composition) comprises (A) a white pigment, (B) an alkali soluble resin, (C) a polymerizable compound, (D) The photopolymerization initiator and the (E) solvent are contained, and the (A) white pigment is contained in an amount of 30 to 90% by mass when the total amount of components excluding the (E) solvent is 100% by mass.

According to such a present composition, since it contains a relatively high concentration of (A) white pigment, a cured film having a high light reflection function can be formed. Furthermore, by including (B) an alkali soluble resin, (C) a polymerizable compound, and (D) a photopolymerization initiator, a cured film having a fine pattern shape of a desired shape can be easily formed. The composition can be suitably used as a material for forming a minute component for which light reflection performance is required in a display element, in particular, as a material for forming a partition of an organic EL element or a micro LED element.
Below, each component etc. are demonstrated.

<(A) White pigment>
(A) As the white pigment, for example, alumina, magnesium oxide, antimony oxide, titanium oxide, zirconium oxide, aluminum hydroxide, magnesium hydroxide, barium sulfate, magnesium carbonate, barium carbonate, calcium carbonate, lead sulfate, lead phosphate, Zinc phosphate, silicon dioxide, zinc oxide, tin oxide, strontium sulfide, strontium titanate, barium tungstate, lead metasilicate, talc, kaolin, clay, bismuth chloride, hollow silica particles, organic hollow particles, core shell particles, etc. You can choose from

  (A) The white pigment comprises at least one 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 It is preferable to contain, and it is preferable to contain especially a titanium oxide. Since the said inorganic substance has high refractive index, it can improve the reflective characteristic of the cured film formed. Among them, titanium oxide has a particularly high refractive index, and is further preferable from the viewpoint of the dispersion property to a solvent.

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

  The content of the white pigment (A) is 30 to 90 mass%, preferably 40 to 85 mass%, when the total amount of components excluding the solvent (E) of the present composition is 100 mass%. More preferably, it is 45 to 80% by mass. The upper limit of the content of the white pigment (A) may be even more preferably 75% by mass, 70% by mass, 65% by mass, or 60% by mass. When the content of the white pigment (A) is 30% by mass or more, the formed cured film can have high light reflection properties. On the other hand, if the content of (A) white pigment is 90% by mass or less, adjustment of other components for forming a fine pattern becomes easy, and it becomes easy to form a fine pattern having a desired shape. .

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

  (B) The alkali-soluble resin preferably contains an acidic group. As an acidic group, a carboxyl group, an acid anhydride group, phenolic hydroxyl group, and a sulfo group are mentioned, for example. Among the above, as the acidic group, at least one 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 one or more acidic groups.

  As the alkali-soluble resin (B) having a carboxyl group, in particular, a monomer having one or more carboxyl groups (hereinafter, abbreviated as a "carboxyl-containing monomer") and another copolymerizable monomer Copolymers with (hereinafter abbreviated as "copolymerizable monomers") are preferred.

  As a carboxyl group-containing monomer, for example, (meth) acrylic acid, crotonic acid, α-chloroacrylic acid, unsaturated monocarboxylic acid such as cinnamic acid; maleic acid, maleic anhydride, fumaric acid, itaconic acid, itaconic anhydride Acid, citraconic acid, citraconic anhydride, unsaturated dicarboxylic acid such as mesaconic acid or anhydride thereof; succinic acid mono [2- (meth) acryloyloxyethyl], phthalic acid mono [2- (meth) acryloyloxyethyl A mono ([meth) acryloyloxyalkyl] ester of a polyvalent carboxylic acid having a valence of 2 or more; a mono ((meth) acryloyloxyalkyl) ester of a polymer having a carboxy group and a hydroxyl group at both ends such as ω-carboxypolycaprolactone mono (meth) acrylate Meta) acrylate etc. can be mentioned. The above-mentioned carboxyl group-containing monomers can be used alone or in combination of two or more.

  As the carboxyl group-containing monomer, (meth) acrylic acid, succinic acid mono [2- (meth) acryloyloxyethyl], and ω-carboxypolycaprolactone mono (meth) acrylate are preferable, and in particular (meth) acrylic acid Is preferred.

  As a monomer which gives a structural unit which has phenolic hydroxyl group, 4-vinylphenol, 4-isopropenyl phenol, 4-hydroxyphenyl (meth) acrylate etc. can be mentioned.

  The content of the structural unit having an acidic group in the (B) alkali-soluble resin is preferably 1 to 50% by mass, more preferably 3 to 40% by mass, still more preferably 100% by mass of the alkali-soluble resin (B) Is 5 to 30% by mass. By setting the content of the structural unit having an acidic group to 1% by mass or more, the solubility of the obtained present composition in an alkaline developer can be enhanced, and by setting the content to 50% by mass or less, the alkali developer It can suppress that the solubility with respect to these becomes excessive, and when developing with an alkaline developing solution, it is possible to particularly sufficiently suppress the detachment from the substrate and the film roughness on the surface.

  Moreover, it is preferable that Si (silicon) atom or F (fluorine) atom is contained in (B) alkali-soluble resin, and it is preferable that especially F atom is contained. By containing such an atom, liquid repellency is imparted to the (B) alkali-soluble resin. As a result, it becomes easy to apply a composition for forming a color filter, a composition for forming a phosphor layer, etc. between cured films formed of the present composition, and by using the above-mentioned cured film as a partition wall It becomes easy to form the display element which possesses functionality.

  When (B) alkali-soluble resin contains F atom, it is preferable that especially the group represented by following formula (1) is contained.

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, the plurality of R ^{1 s} may be the same or different, and the plurality of R ^{2 s} may be the same or different. * Represents a binding site.

  When the (B) alkali-soluble resin has a group represented by the above formula (1), the (B) alkali-soluble resin is given appropriate liquid repellency. As a result, as described above, it becomes easy to form a display device having high functionality.

  As a lower limit of n in the said Formula (1), 3 is preferable and 5 is more preferable. As the upper limit of n, 8 may be preferable.

  Here, as a group represented by the said Formula (1), Preferably the group represented by following formula (2) and following formula (3) is mentioned.

  In formulas (2) and (3), A is independently the same as the above formula (1), and in formula (2), x is an integer of 0 to 2 and y is an integer of 1 to 8 In the formula (3), z is an integer of 1 to 5.

  As a lower limit of x in the said Formula (2), 1 is preferable and 2 is more preferable. As a lower limit of y, 2 is preferable and 4 is more preferable. As the upper limit of y, 6 may be preferable.

  As A in the above formulas (1) to (3), an ester bond is preferable. In addition, an ester bond is a bivalent group represented by -C (= O) O-, The direction is not limited. However, it is preferable that the binding site (*) side is a carbonyl group (-C (= O)-).

  The alkali-soluble resin (B) preferably contains a structural unit containing Si atom or F atom, and more preferably contains a structural unit containing F atom. As a structural unit containing F atom, a structural unit having a group represented by the above formula (1) is preferable. As a monomer which gives a structural unit which has a group represented by the said Formula (1), the monomer represented by following formula (4) can be mentioned.

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

As R ³ in the above formula (4), a hydrogen atom or a methyl group is preferable.

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

  It is preferable that content of the structural unit containing Si atom or F atom in (B) alkali-soluble resin is 1-70 mass% with respect to 100 mass% of (B) alkali-soluble resin. If it is in this range, it becomes easy to give a suitable liquid-repellent property to the (B) alkali-soluble resin. Further, the content of the structural unit containing Si atom or F atom is more preferably 3% by mass to 50% by mass, and still more preferably 5% by mass to 45% with respect to 100% by mass of the (B) alkali-soluble resin. It is mass%. If the content of structural units containing Si atoms or F atoms is in this range, in addition to the above effects, the developability of the present composition can be further enhanced. From the viewpoint of liquid repellency and the like, the lower limit of the content of the structural unit containing Si atom or F atom is preferably 10% by mass, and more preferably 20% by mass.

  Further, the (B) alkali-soluble resin preferably has a polymerizable group, and more preferably has a structural unit containing a polymerizable group, for the purpose of improving the sensitivity and the like. The polymerizable group is preferably at least one selected from the group consisting of (meth) acryloyl group, vinyl group, oxiranyl group and oxetanyl group. (B) When the alkali-soluble resin has the above-mentioned specific polymerizable group, the cured film formed by the present composition has high surface curability, is excellent in deep-portion curability, and also improves heat resistance.

Among the above polymerizable groups, an oxiranyl group and an oxetanyl group are preferable, and an oxiranyl group is more preferable. As a monomer giving a structural unit containing a polymerizable group, glycidyl (meth) acrylate, 3- (meth) acryloyloxymethyl-3-ethyl oxetane, 3,4-epoxycyclohexylmethyl (meth) acrylate, 3, 4-epoxytricyclo [5.2.1.0 ^2.6 ] decyl (meth) acrylate and the like can be mentioned.

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

  Further, the (B) alkali-soluble resin may be a polymer containing a ring structure to improve heat resistance. It is preferable that the said ring structure is contained in the principal chain of (B) alkali-soluble resin. The alkali-soluble resin (B) preferably has a structural unit containing a ring structure, and more preferably has a structural unit containing a ring structure in the main chain. Moreover, as a number of ring members of this ring structure, although it may be 3-12, for example, 5-8 are preferable.

  As a monomer giving a structural unit containing a ring structure, N-substituted maleimide-based monomer, dialkyl-2,2 '-(oxydimethylene) diacrylate-based monomer, α- (unsaturated alkoxyalkyl) acrylate And tricyclodecanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, styrene, vinyl phenyl ether and the like. Moreover, the monomer which gives the structural unit which has oxiranyl group or oxetanyl group mentioned above can also be mentioned.

  Among them, a copolymer introduced from at least one selected from the group consisting of N-substituted maleimide monomers, tricyclodecanyl (meth) acrylate and dicyclopentenyl (meth) acrylate has high heat resistance. It is preferable from the viewpoint of having.

  Among these monomers, an N-substituted maleimide-based monomer is preferable from the viewpoint of being able to introduce a ring structure in the main chain and expressing better heat resistance. The N-substituted maleimide monomer is a compound in which a hydrogen atom bonded to a nitrogen atom in maleimide is substituted by a substituent. As said substituent, a hydrocarbon group is preferable, the hydrocarbon group which has ring structure is more preferable, and an aromatic hydrocarbon group is more preferable. Examples of the N-substituted maleimide monomer include N-phenyl maleimide, N-naphthyl maleimide, N-cyclohexyl maleimide, N-cyclooctyl maleimide, N-methyl maleimide and the like.

  The content of the structural unit having a ring structure in the (B) alkali-soluble resin is preferably 5 to 80% by mass, and more preferably 10 to 50% by mass with respect to 100% by mass of the (B) alkali-soluble resin In some cases, 15 to 30% by mass is more preferable.

  The alkali-soluble resin (B) can be easily obtained by polymerization using one or more monomers such as the above-mentioned carboxyl group-containing monomer. Moreover, in the case of the synthesis | combination of (B) alkali-soluble resin, you may synthesize | combine using other monomers other than each monomer mentioned above arbitrarily.

  The alkali-soluble resin (B) may be used alone or in combination of two or more. (B) As a specific example using two or more types of alkali-soluble resins, it is possible to use an alkali-soluble resin having many structural units containing an acidic group and an alkali-soluble resin containing many Si atoms or F atoms in combination. It can be mentioned. As described above, the present composition having excellent display element moldability can be obtained by properly using two or more kinds of alkali-soluble resins in accordance with the functionality.

  Further, the weight average molecular weight (Mw) in terms of polystyrene of the alkali-soluble resin (B) is preferably 2,000 to 500,000, more preferably 3, in the value measured by gel permeation chromatography (GPC). It is preferably in the range of from 00 to 100,000, more preferably from 4,000 to 50,000.

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

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

<(C) polymerizable compound>
The (C) polymerizable compound refers to a compound having two or more polymerizable groups. However, (B) alkali-soluble resin is excluded. Examples of the polymerizable group include an ethylenically unsaturated group, an oxiranyl group, an oxetanyl group, and an N-alkoxymethylamino group. The polymerizable compound is preferably a compound having two or more (meth) acryloyl groups or a compound having two or more N-alkoxymethylamino groups.

  Specific examples of the compound having two or more (meth) acryloyl groups include polyfunctional (meth) acrylates obtained by reacting an aliphatic polyhydroxy compound with (meth) acrylic acid, and caprolactone-modified polyfunctional ( (Meth) acrylate, alkylene oxide modified polyfunctional (meth) acrylate, polyfunctional urethane (meth) acrylate obtained by reacting (meth) acrylate having hydroxyl group with polyfunctional isocyanate, (meth) acrylate having hydroxyl group The polyfunctional (meth) acrylate etc. which have a carboxyl group obtained by making it react with an acid anhydride can be mentioned.

  Here, examples of the aliphatic polyhydroxy compounds include divalent aliphatic polyhydroxy compounds such as ethylene glycol, propylene glycol, polyethylene glycol and polypropylene glycol; trivalent compounds such as glycerin, trimethylolpropane, pentaerythritol and dipentaerythritol The above-mentioned aliphatic polyhydroxy compounds can be mentioned. As the (meth) acrylate having a hydroxyl group, for example, 2-hydroxyethyl (meth) acrylate, trimethylolpropane di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, glycerol di Methacrylate etc. can be mentioned. Examples of the polyfunctional isocyanate include tolylene diisocyanate, hexamethylene diisocyanate, diphenylmethylene diisocyanate, isophorone diisocyanate and the like. Examples of the acid anhydride include, for example, succinic anhydride, maleic anhydride, glutaric anhydride, itaconic anhydride, phthalic anhydride, phthalic anhydride, dibasic acid anhydride such as hexahydrophthalic anhydride, pyromellitic anhydride, biphenyl tetracarboxylic acid Anhydrides and tetrabasic acid dianhydrides such as benzophenone tetracarboxylic acid dianhydride can be mentioned.

  Moreover, as a caprolactone modified polyfunctional (meth) acrylate, the compound described in stage-of Unexamined-Japanese-Patent No. 11-44955 can be mentioned, for example. The alkylene oxide-modified polyfunctional (meth) acrylate is at least one selected from bisphenol A di (meth) acrylate modified with at least one selected from ethylene oxide and propylene oxide, ethylene oxide and propylene oxide Modified isocyanurate tri (meth) acrylate, modified with at least one selected from trimethylolpropane tri (meth) acrylate modified with at least one selected from ethylene oxide and propylene oxide, ethylene oxide and propylene oxide At least one selected from pentaerythritol tri (meth) acrylate, ethylene oxide and propylene oxide Modified with at least one selected from pentaerythritol tetra (meth) acrylate, ethylene oxide and propylene oxide, dipentaerythritol penta (meth) acrylate modified with at least one selected from ethylene oxide and propylene oxide Pentaerythritol hexa (meth) acrylate etc. can be mentioned.

  Moreover, as a compound which has a 2 or more N- alkoxy methylamino group, the compound etc. which have a melamine structure, a benzoguanamine structure, or a urea structure can be mentioned, for example. The melamine structure or benzoguanamine structure is a chemical structure having one or more triazine rings or phenyl-substituted triazine rings as a basic skeleton, and is a concept including also melamine, benzoguanamine or their condensates. Specific examples of the compound having two or more N-alkoxymethylamino groups include N, N, N ′, N ′, N ′ ′, N ′ ′, N ′ ′-hexa (alkoxymethyl) melamine, N, N, N ′. , N′-tetra (alkoxymethyl) benzoguanamine, N, N, N ′, N′-tetra (alkoxymethyl) glycoluril, and the like.

  (C) Among the polymerizable compounds, polyfunctional (meth) acrylates, caprolactone-modified polyfunctional (meth) acrylates, and polyfunctional (meth) acrylates obtained by reacting trivalent or higher aliphatic polyhydroxy compounds with (meth) acrylic acid Functional urethane (meth) acrylates, N, N, N ', N', N '', N ''-hexa (alkoxymethyl) melamine, and N, N, N ', N'-tetra (alkoxymethyl) benzoguanamine preferable. Among the polyfunctional (meth) acrylates obtained by reacting a trivalent or higher aliphatic polyhydroxy compound with (meth) acrylic acid, trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentadiene Erythritol pentaacrylate and dipentaerythritol hexaacrylate have high strength of the cured film, excellent surface smoothness of the cured film, and are less likely to generate ground stains, film residue, etc. on the substrate and light shielding layer of the unexposed area It is particularly preferable in point.

  The polymerizable compound (C) may contain an Si atom or an F atom, and in particular, preferably contains an F atom. By containing such an atom, the liquid repellent property is imparted to the (C) polymerizable compound. As a result, it becomes easy to apply a composition for forming a color filter, a composition for forming a phosphor layer, etc. between cured films formed of the present composition, and by using the above-mentioned cured film as a partition wall It becomes easy to form the display element which possesses functionality.

  As the (C) polymerizable compound containing an F atom, for example, those in which part or all of the hydrogen atoms of the hydrocarbon group possessed by the polyfunctional (meth) acrylate are substituted with an F atom, a polyfunctional containing a perfluoroalkyl group Examples include (meth) acrylates and the like. Moreover, as a (C) polymeric compound containing Si atom, the polyfunctional (meth) acrylate etc. which have structures, such as a silyl group, a polyalkyl siloxane, silsesquioxane, etc. can be mentioned, for example. In addition, polysiloxane having a plurality of polymerizable groups such as oxiranyl group and oxetanyl group can also 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 in total of the white pigment (A). . In addition, the content of the polymerizable compound (C) is usually 20 to 300 parts by mass, preferably 30 to 250 parts by mass, more preferably 50 to 200 parts by mass with respect to 100 parts by mass of the (B) alkali-soluble resin. is there. By setting it as such an aspect, the cured film which is excellent in heat resistance and chemical resistance can be formed.

<(D) Photopolymerization initiator>
The photopolymerization initiator (D) is a compound which generates an active species capable of initiating polymerization of the polymerizable compound (C) upon exposure to radiation such as visible light, ultraviolet light, far ultraviolet light, electron beam, X-ray and the like. A photoinitiator can be used 1 type or in mixture of 2 or more types.

  Examples of such (D) photopolymerization initiators include thioxanthone compounds, acetophenone compounds, biimidazole compounds, triazine compounds, O-acyloxime compounds, onium salt compounds, benzoin compounds and benzophenone compounds Acyl phosphine oxide compounds, titanocene compounds, α-diketone compounds, polynuclear quinone compounds, diazo compounds, imidosulfonate compounds, onium salt compounds and the like can be mentioned. Among them, at least one selected from O-acyloxime compounds, acetophenone compounds, acyl phosphine oxide compounds and titanocene compounds is preferable.

  Examples of O-acyloxime compounds include 1,2-octanedione, 1- [4- (phenylthio) phenyl]-, 2- (O-benzoyloxime), ethanone, 1- [9-ethyl-6- ( 2-Methylbenzoyl) -9H-carbazol-3-yl]-, 1- (O-acetyloxime), ethanone, 1- [9-ethyl-6- (2-methyl-4-tetrahydrofuranylmethoxybenzoyl) -9H -Carbazol-3-yl]-, 1- (O-acetyloxime), ethanone, 1- [9-ethyl-6- {2-methyl-4- (2,2-dimethyl-1,3-dioxolanyl) methoxy] Benzoyl} -9H-carbazol-3-yl]-, 1- (O-acetyloxime), 1-octanone, 1- [4- [3- [4-[[2- (acetyloxy) ethyl] Sulfonyl] -2-methylbenzoyl] -6- [1 - [(acetyloxy) imino] ethyl]-9H-carbazol] -9-yl] phenyl, 1-(O-acetyl oxime), and the like. Commercially available products of O-acyloxime compounds include NCI-831, NCI-930 (above, made by ADEKA Co., Ltd.), DFI-020, DFI-091 (above, made by Daitoke Mix Co., Ltd.), IrgacureOXE-03, IrgacureOXE -04 (above, BASF Corporation make) etc. can also be used.

  Among these O-acyloxime compounds, ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl]-, 1- (O-acetyloxime), 1- Octanone, 1- [4- [3- [4-[[2- (acetyloxy) ethyl] sulfonyl] -2-methylbenzoyl] -6- [1-[(acetyloxy) imino] ethyl] -9H-carbazole ] -9-yl] phenyl, 1- (O-acetyloxime) is preferred.

  The acetophenone compound is more preferably an α-aminoalkylphenone compound, for example, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino -1- (4-morpholinophenyl) butan-1-one, 2- (4-methylbenzyl) -2- (dimethylamino) -1- (4-morpholinophenyl) butan-1-one and the like Can.

  Among these acetophenone compounds, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one, and 2-benzyl-2-dimethylamino-1- (4-morpholino) Phenyl) butan-1-one is preferred.

  Examples of the acyl phosphine oxide compounds include isobutyryl methyl phosphinic acid methyl ester, iso butyryl phenyl phosphinic acid methyl ester, pivaloyl phenyl phosphinic acid methyl ester, 2-ethylhexanoyl phenyl phosphinic acid methyl ester, pivaloyl Phenyl phosphinic acid isopropyl ester, p-toluylphenyl phosphinic acid methyl ester, o-toluylphenyl phosphinic acid methyl ester, 2,4-dimethyl benzoyl phenyl phosphinic acid methyl ester, p-t-butyl benzoyl phenyl phosphinic acid isopropyl ester, acryloyl phenyl Phosphinic acid methyl ester, isobutyryl diphenyl phosphine oxide, 2-ethylhexanoyl diphenyl phosphine oxide O-toluyl diphenyl phosphine oxide, p-t-butyl benzoyl diphenyl phosphine oxide, 3-pyridylcarbonyl diphenyl phosphine oxide, acryloyl-diphenyl phosphine oxide, benzoyl diphenyl phosphine oxide, pivaloyl phenyl phosphinic acid vinyl ester, adipoyl bis diphenyl Phosphine oxide, pivaloyl diphenyl phosphine oxide, p-toluyl diphenyl phosphine oxide, 4- (t-butyl) benzoyl diphenyl phosphine oxide, terephthaloyl bis diphenyl phosphine oxide, 2-methyl benzoyl diphenyl phosphine oxide, versatoyl diphenyl phosphine oxide , 2-methyl-2-ethylhexanoyldi Monoacyl phosphine oxides such as phenenyl phosphine oxide, 1-methyl-cyclohexanoyl diphenyl phosphine oxide, pivaloyl phenyl phosphinic acid methyl ester, pivaloyl phenyl phosphinic acid isopropyl ester, 2,4,6-trimethyl benzoyl diphenyl phosphine oxide Bis (2,6-dichlorobenzoyl) phenyl phosphine oxide, bis (2,6-dichlorobenzoyl) -2,5-dimethylphenyl phosphine oxide, bis (2,6-dichlorobenzoyl) -4-ethoxyphenyl phosphine oxide, Bis (2,6-dichlorobenzoyl) -4-propylphenyl phosphine oxide, bis (2,6-dichlorobenzoyl) -2-naphthyl phosphine oxide, bis (2 , 6-Dichlorobenzoyl) -1-naphthyl phosphine oxide, bis (2,6-dichlorobenzoyl) -4-chlorophenyl phosphine oxide, bis (2,6-dichlorobenzoyl) -2,4-dimethoxyphenyl phosphine oxide, bis ( 2,6-Dichlorobenzoyl) decyl phosphine oxide, bis (2,6-dichlorobenzoyl) -4-octylphenyl phosphine oxide, bis (2,4,6-trimethyl benzoyl) phenyl phosphine oxide, bis (2,4,6 -Trimethylbenzoyl) -2,5-dimethylphenyl phosphine oxide, bis (2,6-dichloro 3,4,5-trimethoxybenzoyl) -2,5-dimethylphenyl phosphine oxide, bis (2,6-dichloro-3 , 4, 5-tri (Toxybenzoyl) -4-ethoxyphenyl phosphine oxide, bis (2-methyl-1-naphthoyl) -2,5-dimethylphenyl phosphine oxide, bis (2-methyl-1-naphthoyl) -4-ethoxyphenyl phosphine oxide, bis (2-Methyl-1-naphthoyl) -2-naphthyl phosphine oxide, bis (2-methyl-1-naphthoyl) -4-propylphenyl phosphine oxide, bis (2-methyl-1-naphthoyl) -2,5-dimethyl Phenyl phosphine oxide, bis (2-methoxy-1-naphthoyl) -4-ethoxyphenyl phosphine oxide, bis (2-chloro-1-naphthoyl) -2,5-dimethylphenyl phosphine oxide, bis (2,6-dimethoxybenzoyl) ) -2,4,4- Bisacylphosphine oxides such as trimethyl pentyl phosphine oxide; and the like. In addition, the acyl phosphine compounds described in JP-A-3-101686, JP-A-5-345790, and JP-A-6-298818 can also be used.

  Among these acyl phosphine oxide compounds, as the monoacyl phosphine oxide, 2,4,6-trimethyl benzoyl diphenyl phosphine oxide (for example, Darocur TPO manufactured by BASF Corp.) is preferable, and as the bisacyl phosphine oxide, bis (2,4,6 , 6-trimethyl benzoyl) phenyl phosphine oxide (for example, BASF Corporation Irgacure 819), and bis (2, 6-dimethoxy benzoyl)-2, 4, 4- trimethyl pentyl phenyl phosphine oxide (for example BASF Corporation Irgacure 1700) are preferable. And bis (2,4,6-trimethylbenzoyl) phenyl phosphine oxide is more preferable.

  Examples of titanocene photo compounds include bis (cyclopentadienyl) -Ti-dichloride, bis (cyclopentadienyl) -Ti-bis-phenyl and bis (cyclopentadienyl) -Ti-bis-2, 3,4,5,6-pentafluorophenyl, bis (cyclopentadienyl) -Ti-bis-2,3,5,6-tetrafluorophenyl, bis (cyclopentadienyl) -Ti-bis-2, 4,6-trifluorophenyl, bis (cyclopentadienyl) -Ti-bis-2,6-difluorophenyl, bis (cyclopentadienyl) -Ti-bis-2,4-difluorophenyl, bis (methylcyclo) Pentadienyl) -Ti-bis-2,3,4,5,6-pentafluorophenyl, bis (methylcyclopentadienyl) -Ti-bis-2 3,5,6-Tetrafluorophenyl, bis (methylcyclopentadienyl) -Ti-bis-2,6-difluorophenyl (for example, Irgacure 727L manufactured by BASF Corp.), bis (cyclopentadienyl) -bis (2,2, 6-difluoro-3- (pyr-1-yl) phenyl) titanium (eg, manufactured by BASF, Irgacure 784), bis (cyclopentadienyl) -bis (2,4,6-trifluoro-3- (pyr-1) -Yl) phenyl) titanium bis (cyclopentadienyl) -bis (2,4,6-trifluoro-3- (2-5-dimethylpyri-1-yl) phenyl) titanium etc. and the like. .

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

  As (D) photoinitiators other than the above, what is illustrated, for example to stage-of Unexamined-Japanese-Patent No. 2010-134419 can be mentioned.

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

  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, with respect to 100 parts by mass of the polymerizable compound (C). . By setting it as such an aspect, the cured film which is excellent in heat resistance, chemical resistance, hardenability, etc. can be formed.

<(E) Solvent>
The present composition contains the above-mentioned components (A) to (D) and optionally added other components, but usually, it is mixed with (E) a solvent such as an organic solvent to obtain a liquid composition. Be prepared.
(E) As a solvent, as long as the components (A) to (D) and other components constituting the composition are dispersed or dissolved and do not react with these components and have appropriate volatility. And can be appropriately selected and used.

  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-n-propyl ether, propylene glycol mono-n-butyl ether Propylene glycol monomethyl ether, di (Poly) alkylene glycol monoalkyl ethers such as ropylene glycol monoethyl ether, dipropylene glycol mono-n-propyl ether, dipropylene glycol mono-n-butyl ether, tripropylene glycol monomethyl ether, tripropylene glycol monoethyl ether, etc .; methyl lactate Lactic acid alkyl esters such as ethyl lactate; (cyclo) alkyl alcohols such as methanol, ethanol, propanol, butanol, isopropanol, isobutanol, t-butanol, octanol, 2-ethylhexanol, cyclohexanol; keto alcohols such as diacetone alcohol 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 acetate, dipropylene glycol monomethyl ether acetate, 3-methoxybutyl acetate, 3-methyl-3 (Poly) alkylene glycol monoalkyl ether acetates such as methoxybutyl acetate; glycol ethers such as diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol diethyl ether, tetrahydrofuran and the like; ketones such as methyl ethyl ketone, cyclohexanone, 2-heptanone and 3-heptanone; Glycol diacetate Di-acetates such as 1,3-butylene glycol diacetate and 1,6-hexanediol diacetate; methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, 3-ethoxypropionic acid Ethyl, ethoxyethyl carbonate, alkoxycarboxylic acid esters such as 3-methyl-3-methoxybutyl propionate; ethyl acetate, n-propyl acetate, i-propyl acetate, n-butyl acetate, i-butyl acetate, n-formic acid -Amyl, i-amyl acetate, n-butyl propionate, ethyl butyrate, n-propyl butyrate, i-propyl butyrate, n-butyl butyrate, methyl pyruvate, ethyl pyruvate, n-propyl pyruvate, methyl acetoacetate, Fatty acid alkyl esters such as ethyl acetoacetate and ethyl 2-oxobutanoate Le: toluene, xylene and like aromatic hydrocarbons; N, N- dimethylformamide, N, N- dimethylacetamide may be mentioned N- amides such as methylpyrrolidone, or lactam.

  Among these organic solvents, (poly) alkylene glycol monoalkyl ether, lactic acid alkyl ester, (poly) alkylene glycol monoalkyl ether acetate, glycol from the viewpoint of solubility, (A) dispersibility of white pigment, coatability, etc. Ethers, ketones, diacetates, alkoxycarboxylic acid esters, fatty acid alkyl esters are preferred, and particularly propylene glycol monomethyl ether, propylene glycol monoethyl ether, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, -Methoxybutyl acetate, diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, cyclohexene Non-, 2-heptanone, 3-heptanone, 1,3-butylene glycol diacetate, 1,6-hexanediol diacetate, ethyl lactate, ethyl 3-methoxypropionate, 3-ethoxy propionate, n-butyl acetate, acetic acid Preferred are i-butyl, n-amyl formate, i-amyl acetate, n-butyl propionate, ethyl butyrate, i-propyl butyrate, n-butyl butyrate, ethyl pyruvate and the like.

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

  In the present composition, the (E) solvent may be used alone or in combination of two or more. The content of the solvent (E) is not particularly limited, but an amount such that the total concentration of all components excluding the solvent (E) of the present composition is 5 to 70 mass% is preferable, and 10 to 60. More preferably, the amount is to be% by mass. By adopting such an embodiment, the present composition having good coatability and storage stability can be obtained.

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

  Examples of known dispersants include urethane dispersants, polyethyleneimine dispersants, polyoxyethylene alkyl ether dispersants, polyoxyethylene alkylphenyl ether dispersants, polyethylene glycol diester dispersants, sorbitan fatty acid ester dispersants Agents, polyester dispersants, (meth) acrylic dispersants, phosphate ester dispersants and the like. Examples of commercially available products include (meth) acrylic dispersants such as Disperbyk-2000, Disperbyk-2001, Disperbyk-182, Disperbyk-184, BYK-LPN 6919, BYK-LPN 21116 (above, manufactured by BYK Chemie), Disperbyk -161, Disperbyk-162, Disperbyk-165, Disperbyk-167, Disperbyk-170, Disperbyk-182 (above, made by BIC Chemie (BYK) company), urethane type dispersing agents, such as Sols spars 76500 (made by Lubrizol Corporation), Sols spars Polyethyleneimine-based dispersants such as 24000 (manufactured by Lublisol Co., Ltd.), ADISPAR PB 821, ADISPAR PB 822, ADISPAR P In addition to polyester dispersants such as 880 and ADISPAR PB 881 (all manufactured by Ajinomoto Fine Techno Co., Ltd.), and phosphate ester dispersants such as Disperbyk-110 and Disperbyk-180, BYK-LPN 21324 (Bick Chemie (BYK) Co., Ltd.) ) Can be used.

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

  The dispersant preferably has an acid value of 30 to 200 mg KOH / g or an amine value of 10 to 200 mg KOH / g from the viewpoint of improving the storage stability. From the viewpoint of the dispersibility of the (A) white pigment, the acid value is more preferably 40 to 100 mg KOH / g, and the amine value is more preferably 20 to 180 mg KOH / g. Here, "amine value" represents the number of milligrams of KOH and an equivalent of HCl necessary to neutralize 1 g of solid content.

  The dispersants can be used alone or in combination of two or more. When two or more kinds are mixed and used, it is preferable to include at least a (meth) acrylic dispersant, and the content ratio of the (meth) acrylic dispersant is preferably 50% by mass or more with respect to the entire dispersant, 70 mass% or more is more preferable. By adopting such an embodiment, it becomes easy to obtain the present composition with even better storage stability.

  The content of the dispersant is usually 0.5 to 50 parts by mass, preferably 2 to 30 parts by mass with respect to 100 parts by mass of the (A) white pigment. By setting it as such an aspect, this composition which is excellent in storage stability can be formed.

  It is preferable that this composition contains (B) alkali-soluble resin and a dispersing agent as an ingredient which plays a role as a binder. The total content of the (B) alkali-soluble resin and the dispersant is preferably 2 to 150 parts by mass, more preferably 10 to 70 parts by mass with respect to 100 parts by mass of the total of the (A) white pigment.

<(F) surfactant>
The composition can further include (F) a surfactant. By using the surfactant (F), the coating film formability of the present composition can be enhanced, and the surface smoothness of the resulting coating film can be enhanced. As a result, the film thickness uniformity of the obtained cured film can be further improved.

  In addition, the (F) surfactant may contain a Si atom or an F atom, and specifically includes compounds described in JP 2003-015278 and JP 2013-231869. It may be done. By containing such an atom, liquid repellency is imparted to the (F) surfactant. As a result, it becomes easy to apply a composition for forming a color filter, a composition for forming a phosphor layer, etc. between cured films formed of the present composition, and by using the above-mentioned cured film as a partition wall It becomes easy to form the display element which possesses functionality.

  The content thereof in the present composition when (F) a surfactant is used is preferably 20 parts by mass or less, more preferably 0.01 to 15 parts by mass with respect to 100 parts by mass of (B) the alkali-soluble resin More preferably, it is 0.05-10 mass parts. By making content of surfactant (F) into the said range, the film thickness uniformity of the coating film formed can be improved more.

  The composition further comprises (F) a surfactant, as described above, and at least one selected from the group consisting of (B) an alkali-soluble resin, (C) a polymerizable compound and (F) a surfactant. The species preferably contains Si atoms or F atoms.

<Additives>
The composition can also contain various additives, as needed. Examples of the additive include fillers such as glass and alumina; polymer compounds such as polyvinyl alcohol and poly (fluoroalkyl acrylate); vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (2-methoxyethoxy) silane N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-glycidoxypropyltriol Methoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropyltrimethoxysilane, 3-methacryloyloxypropyl bird Adhesion promoters such as silane coupling agents such as toxisilane and 3-mercaptopropyltrimethoxysilane; 2,2-thiobis (4-methyl-6-t-butylphenol), 2,6-di-t-butylphenol, pentaerythritol Tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 3,9-bis [2- [3- (3-t-butyl-4-hydroxy-5-methylphenyl), -Propionyloxy] -1,1-dimethylethyl] -2,4,8,10-tetraoxa-spiro [5.5] undecane, thiodiethylene bis [3- (3,5-di-t-butyl-4-4 Hydroxyphenyl) propionate], an antioxidant such as tris (2,4-di-t-butylphenyl) phosphite, and the like; 2- (3-t-butyl-5-) UV absorbers such as ethyl 2-hydroxyphenyl) -5-chlorobenzotriazole and alkoxybenzophenones; anticoagulation agents such as sodium polyacrylate; malonic acid, adipic acid, itaconic acid, citraconic acid, fumaric acid, mesaconic acid , 2-aminoethanol, 3-amino-1-propanol, 5-amino-1-pentanol, 3-amino-1,2-propanediol, 2-amino-1,3-propanediol, 4-amino-1 Residue improving agents such as 2-butanediol; succinic acid mono [2- (meth) acryloyloxyethyl], phthalic acid mono [2- (meth) acryloyloxyethyl], ω-carboxypolycaprolactone mono (meth) Examples thereof include developability improvers such as acrylates. The adhesion promoter does not correspond to the (C) polymerizable compound.

  Among the above additives, the content of the adhesion promoter such as a silane coupling agent is preferably 1 to 20 parts by mass, and more preferably 3 to 15 parts by mass with respect to 100 parts by mass of the (B) alkali-soluble resin. . Moreover, as content of antioxidant, 0.1-10 mass parts is preferable with respect to 100 mass parts of (B) alkali-soluble resin, and 1-5 mass parts is more preferable. The content of the total of the additives (components other than the components (A) to (F) and the dispersant) in the present composition is preferably 1 to 20 parts by mass with respect to 100 parts by mass of the (B) alkali-soluble resin And 5 to 15 parts by weight may be more preferable. By making content of an additive into the said range, the effect of adding an additive can fully be exhibited with the effect of this invention.

  The present composition can be prepared by any appropriate method, and for example, the components (A) to (D) are mixed with the component (E) and other components optionally added. Can be prepared by Among them, (A) white pigment is mixed and dispersed while being crushed in (E) solvent, in the presence of dispersant, and optionally with (B) a part of alkali-soluble resin, for example, using a bead mill, roll mill or the like. To a white pigment dispersion, then (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. The method of preparation by mixing (hereinafter also referred to as preparation method I) is preferable.

  In addition, a colorant different from (A) white pigment and (A) white pigment in (E) solvent, in the presence of dispersant, optionally together with (B) a part of alkali-soluble resin, for example, bead mill, roll mill, etc. The mixture is pulverized and mixed / dispersed into a white pigment dispersion, and the white pigment dispersion is then mixed with (C) a polymerizable compound and, if necessary, (B) an alkali soluble resin (D). It is also possible to adopt a method of preparing by adding and mixing a photopolymerization initiator, (E) solvent and other components (hereinafter also referred to as preparation method II). The white pigment dispersion in Preparation Method II can undergo the step of simultaneously and uniformly dispersing the (A) white pigment and the (A) colorant different from the white pigment in the (E) solvent. The white pigment dispersion in Preparation Method II contains at least (A) a white pigment and a colorant different from (A) a white pigment, (B) an alkali soluble resin and (E) a solvent, but (B) an alkali soluble resin The content ratio of (A) is 80 parts by mass or less, in particular 60 parts by mass or less, and further 45 parts by mass or less with respect to 100 parts by mass of (A) white pigment. Different coloring agents are uniformly dispersed, and a white pigment dispersion liquid excellent in storage stability can be obtained. Preparation method II is useful when the colorant different from (A) the white pigment is a compound which is poorly soluble or insoluble in the solvent (E) such as pigment.

  The preparation method II can also be performed, for example, with reference to the methods described in JP-A-2001-108817, JP-A-2013-205832, and the like.

Cured Film, Display Element, and Method of Manufacturing the Same
The cured film according to an embodiment of the present invention includes (A) a white pigment, and the (A) white pigment has a total solid content of 100% by mass, 30 to 90% by mass. Specifically, a cured film according to an embodiment of the present invention can be formed using the present composition. Moreover, the display element which concerns on one Embodiment of this invention comprises the cured film of this invention as a partition. The partition provided in the display element may be referred to as a bank, a matrix, or the like.

  Hereinafter, the formation method of the cured film used for the partition which comprises a display element is demonstrated. First, after applying the liquid composition of the present composition on the surface of a substrate, prebaking is performed to evaporate the solvent and form a coating film. Then, the coating film is exposed to light through a photomask, and then developed using an alkaline developer to dissolve and remove the unexposed part of the coating film. Thereafter, the cured film is formed in a predetermined arrangement by post-baking.

  As a board | substrate used when forming a cured film, glass, silicon | silicone, a polycarbonate, polyester, an aromatic polyamide, a polyamide imide, a polyimide etc. can be mentioned, for example.

  In addition, these substrates can be subjected to appropriate pretreatment such as chemical treatment with a silane coupling agent, plasma treatment, ion plating, sputtering, gas phase reaction method, vacuum deposition, etc., if desired.

  When the present composition is applied to a substrate, an appropriate application method such as a spray method, roll coating method, spin coating method (spin coating method), slit die coating method (slit coating method), bar coating method, etc. is employed. In particular, spin coating or slit die coating is preferably employed.

  Pre-baking is usually performed by combining vacuum drying and heat drying. Drying under reduced pressure is usually performed until reaching 50 to 200 Pa. Moreover, the conditions of heat-drying are about 1 to 10 minutes normally at 70-110 degreeC.

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

  As a light source of radiation used when forming a cured film, for example, lamp light sources such as xenon lamp, halogen lamp, tungsten lamp, high pressure mercury lamp, ultra high pressure mercury lamp, metal halide lamp, medium pressure mercury lamp, low pressure mercury lamp, argon ion laser And laser light sources such as YAG laser, XeCl excimer laser, nitrogen laser and the like. An ultraviolet LED can also be used as an exposure light source. The wavelength is preferably radiation in the range of 190-450 nm.

  When the cured film formed by the above method is used as a partition of a display element, a pigment or the like such as a composition for forming a color filter or a composition for forming a phosphor layer for forming a color filter or a phosphor layer between the partitions It is preferable to be liquid repellent from the viewpoint of making it easy to apply the composition in which the organic solvent is dispersed in the organic solvent.

  Here, the liquid repellency is measured by measuring the static contact angle of the surface of the cured film to PGMEA using a contact angle meter (automatic contact angle meter CA-V150, manufactured by Kyowa Interface Chemicals Co., Ltd.). The determined result indicates that it is 5 ° or more, 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 °.

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

  Moreover, as the above-mentioned alkali developing solution, for example, sodium carbonate, sodium hydrogen carbonate, sodium hydroxide, sodium hydroxide, potassium hydroxide, tetramethyl ammonium hydroxide, choline, 1,8-diazabicyclo- [5.4.0] -7-undecene An aqueous solution such as 1,5-diazabicyclo- [4.3.0] -5-nonene is preferred.

  An appropriate amount of a water-soluble organic solvent such as methanol or ethanol, a surfactant or the like can be added to the alkali developer. After alkali development, washing is usually carried out.

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

  Post-baking conditions are usually about 10 to 90 minutes at 120 to 300 ° C. The present composition can form a cured film with little yellowing even when the post-baking temperature is 180 to 300 ° C., further 230 to 290 ° C., and further 250 to 280 ° C.

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

  Further, the shape of the cured film can be a shape having a forward taper, a shape having a vertical taper, a shape having an inverse taper, or a substantially circular shape. Here, a shape having a forward taper refers to a shape in which the cured film decreases upward with respect to the substrate, and a shape having a vertical taper refers to a shape in which the cured film extends upward with respect to the substrate. The shape having a constant shape is referred to, and the shape having a reverse taper refers to a shape in which the cured film increases upward with respect to the substrate. When the cured film has a shape having the above-described taper, the taper angle is preferably 50 to 130 °, and more preferably 60 to 120 °.

  The cured film formed from the present composition has a low content of light, since the content of the white pigment is high. The lower limit of the optical density (OD) of the cured film is preferably 0.05 / μm, more preferably 0.1 / μm, and still more preferably 0.2 / μm. On the other hand, the upper limit of the optical density (OD) is preferably 5.0 / μm.

  If necessary, a transparent conductive film can be formed by sputtering or a protective film can be formed on the cured film thus obtained. This composition is useful from the viewpoint of reliability as a partition used for a display element, when yellowing is small even if it passes through heat processing 250 degreeC or more at the time of transparent electrode formation.

  Further, in recent years, there are cases where a color filter or a phosphor layer is provided between the above-mentioned partition walls in response to a demand for high functionality of a 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 the micro LED device, usually, the micro LED is further disposed between the partition walls. Here, when a cured film having high liquid repellency, which is an embodiment of the present invention, is used as a partition of the display element, a composition for forming a color filter or a phosphor layer for forming a color filter, a phosphor layer or the like is formed. As a result of making it easy to apply the composition etc. between the partition walls, a display device having high functionality can be easily manufactured.

  A method of applying the composition for forming a color filter, the composition for forming a phosphor layer, or the like between the partition walls having high liquid repellency can be performed by a known method. Specifically, coating method using a brush or brush, dipping method, spraying method, roll coating method, spin coating method (spin coating method), slit die coating method, bar coating method, flexographic printing, offset printing, screen Examples thereof include known methods such as printing method, ink jet printing, and dispensing method. Among these, a dipping method, a spray method, a spin coating method, a slit die coating method, an offset printing method, a screen printing method, an inkjet method and a dispensing method are preferable, and the inkjet method is particularly preferable.

  In the ink jet method, the defective discharge amount of the composition to be applied is extremely small and has industrially excellent characteristics, but there is also a possibility that ink droplets may land other than the desired point. However, when the partition having high liquid repellency is used, it is difficult for ink droplets to remain on the top of the partition, and the coated ink droplet is likely to enter the inside of the partition, resulting in a good pattern of the coated material. Therefore, when a highly liquid-repellent cured film, which is an embodiment of the present invention, is used as a partition of a display element, a composition for forming a color filter, a composition for forming a phosphor layer, or the like is applied by an inkjet method. By doing this, it is possible to suppress the adhesion of the ink to the portion that does not require application, and to form a desired pattern of a color filter, a phosphor layer, or the like.

  The display element which used the cured film of this invention for the partition of a display element is equipped with the high light extraction function by high reflective characteristic, and the formation easiness of the functional layer between partitions. 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.

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

<Synthesis of Alkali-Soluble Resin>
Synthesis Example 1 (B-1) Synthesis of Alkali-Soluble Resin 250 parts by mass of PGMEA solution in which 8 parts by mass of 2,2′-azobis (2,4-dimethylvaleronitrile) was dissolved after nitrogen substitution in a flask I was charged. Subsequently, 20 parts by mass of methacrylic acid (hereinafter, abbreviated as MA) and 80 parts by mass of methyl methacrylate (hereinafter, abbreviated as MMA) were charged as monomers, and then stirring was gradually started. The temperature of the solution was raised to 70 ° C. and held at this temperature for 5 hours. Thereafter, the reaction product solution was dropped into a large amount of methanol to coagulate the reaction product. The coagulated product was washed with water, redissolved in 200 g of tetrahydrofuran, and coagulated again with a large amount of methanol to obtain (B-1) an alkali-soluble resin. Mw of the obtained (B-1) alkali-soluble resin was 9,500.

Synthesis Example 2 (B-2) Synthesis of Alkali-Soluble Resin As a monomer, 10 parts by mass of 1H, 1H, 2H, 2H-tridecafluorooctyl methacrylate (hereinafter abbreviated as F-containing acrylate), 10 parts by mass of MA, And (B-2) an alkali-soluble resin was synthesized in the same manner as in Synthesis Example 1 except that 80 parts by mass of MMA was used. Mw of obtained (B-2) alkali-soluble resin was 8,900.

Synthesis Example 3 Synthesis of Alkali-Soluble Resin 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 (B-3) Alkali-soluble resin Was synthesized. Mw of the obtained (B-3) alkali-soluble resin was 8,200.

Synthesis Example 4 Synthesis of (B-4) Alkali-Soluble Resin Synthesis Example 1 and 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. Similarly, (B-4) an alkali-soluble resin was synthesized. Mw of obtained (B-4) alkali-soluble resin was 9,800.

Synthesis Example 5 (B-5) Synthesis of Alkali-Soluble Resin As monomers, 40 parts by mass of GMA, 20 parts by mass of MA, 22 parts by mass of N-phenylmaleimide (hereinafter referred to as PMI), and styrene (hereinafter referred to as St and An alkali-soluble resin (B-5) was synthesized in the same manner as in Synthesis Example 1 except that 18 parts by mass was used. Mw of the obtained (B-5) alkali-soluble resin was 8,800.

Synthesis Example 6 (B-6) Synthesis of Alkali-Soluble Resin 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. (B-6) An alkali-soluble resin was synthesized. Mw of the obtained (B-6) alkali-soluble resin was 7,800.

Synthesis Example 7 Synthesis of (B-7) Alkali-Soluble Resin As monomers, 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 4-isopropenylphenol (hereinafter referred to as Hs and An alkali-soluble resin (B-7) was synthesized in the same manner as in Synthesis Example 1 except that 12 parts by mass was used. Mw of the obtained (B-7) alkali-soluble resin was 8,100.

Synthesis Example 8 (B-8) Synthesis of Non-Alkali Soluble Resin 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 (B-8) An alkali soluble resin was synthesized. Mw of the obtained (B-8) non-alkali soluble resin was 9,800.

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

Preparation of White Pigment Dispersion
Preparation Example 1
A. Surface modified with alumina and siloxane C.I. I. Pigment white 6: 1 (titanium oxide) 90 parts by mass, BYK-LPN 21116 (by BIC Chemie (BYK), a (meth) acrylic dispersant, amine value 29 mg KOH / g solids concentration 40 mass%) as a dispersant 25 A mass part and PGMEA as a dispersion medium were used so that solid content concentration might be 50 mass%, and it mixed and disperse | distributed for 12 hours with the bead mill, and prepared (A-1) white pigment dispersion liquid. The average particle diameter of the white pigment in the obtained (A-1) white pigment dispersion was 280 nm.

<Preparation and Evaluation of Curable Composition>
Example 1
(A) 220 parts by mass of (A-1) white pigment dispersion as a dispersion containing white pigment, (B) 100 parts by mass of (B-1) alkali soluble resin as an alkali soluble resin, and (C) KAYARAD as a polymerizable compound 100 parts by mass of DPHA (a mixture of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate manufactured by Nippon Kayaku Co., Ltd.), (D) 10 parts by mass of NCI-930 (manufactured by ADEKA Corporation) as a photopolymerization initiator, (F) 0.5 parts by mass of F-554 (made by DIC Corporation) as a surfactant, 3-glycidoxypropyltrimethoxysilane (made by Shin-Etsu Chemical Co., Ltd.) as a silane coupling agent (adhesion promoter) as an additive 7) parts by weight of pentaerythritol tetrakis [3- (3,5-di-) as an additive antioxidant 3 parts by mass of -butyl-4-hydroxyphenyl) propionate (Irganox 1010 manufactured by BASF), and PGMEA as a solvent (E) are mixed so as to have a solid content concentration of 50% by mass, to form an (S-1) display element A photosensitive composition was prepared.

<Curing film formation for optical density (OD), reflectance, and liquid repellency evaluation>
(S-1) A photosensitive composition for display element formation is coated on a soda glass substrate using a spin coater, and then prebaked at 90 ° C. for 2 minutes on a hot plate to form a coating film having a thickness of 12 μm. did. Next, using a high pressure mercury lamp, the coating film was exposed to radiation containing each wavelength of 365 nm, 405 nm and 436 nm at an exposure dose of 200 J / m ² without using a photomask. After that, shower development is performed by discharging an aqueous solution of 0.04% potassium hydroxide at 23 ° C. at a developing pressure of 1 kgf / cm ² (nozzle diameter 1 mm), and post-baking is further performed at 230 ° C. for 1 hour. Then, a cured film having a thickness of 10 μm was formed on the substrate.

<Formation of cured film for pattern formability and heat resistance evaluation>
(S-1) A photosensitive composition for display element formation is coated on a soda glass substrate using a spin coater, and then prebaked at 90 ° C. for 2 minutes on a hot plate to form a coating film having a thickness of 12 μm. did. Then, using a high pressure mercury lamp, the coating film was exposed to radiation containing each wavelength of 365 nm, 405 nm and 436 nm at an exposure of 50 J / m ² using a photomask of L / S = 10 μm / 30 μm. After that, shower development is performed by discharging an aqueous solution of 0.04% potassium hydroxide at 23 ° C. at a developing pressure of 1 kgf / cm ² (nozzle diameter 1 mm), and post-baking is further performed at 230 ° C. for 1 hour. Then, a cured film having a film thickness of 10 μm and an aspect ratio of 0.8 (film thickness / line width) was formed on the substrate.

[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 types and mixing amounts of the respective components were as described in Table 1. Moreover, the cured film was formed by the method similar to the photosensitive composition for (S-1) display element formations of Example 1. FIG.

<Evaluation>
[Optical density (OD)]
The optical density (OD) of the cured film for evaluation was measured using an optical densitometer (LCF 1100A manufactured by Otsuka Electronics Co., Ltd.). If the OD is 0.2 / μm or more and 5.0 / μm or less, "A +", if 0.1 / μm or more and 0.2 / μm or less, "A", 0.05 / μm or more and 0.1 / or less The case of less than μm was evaluated as “B”, and the case of less than 0.05 / μm was evaluated as “C”. The evaluation results are shown in Table 1.

[Reflectance]
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 measurement apparatus (CM-700D manufactured by Konica Minolta). If the reflectance is 60% or more, it is evaluated as “A +”, if 40% or more and less than 60%, as “A”, if 20% or more and less than 40% as “B”, and if less than 20% as “C” did. The evaluation results are shown in Table 1.

[Pattern formability]
It was visually confirmed whether the unexposed part of the cured film for the said evaluation melt | dissolved completely. When dissolution was confirmed, it was evaluated as "A", and when not confirmed, it was evaluated as "C". The evaluation results are shown in Table 1.

[Liquid repellence]
Using a contact angle meter (manufactured by Kyowa Interface Science Co., Ltd., automatic contact angle meter CA-V150), the static contact angle of PGMEA on the cured film for evaluation was measured to evaluate the liquid repellency. "A +" for contact angles of 30 ° or more and 90 ° or less, "A" for 15 ° or more and less than 30 °, "B" for 10 ° or more and less than 15 and "B" for 5 ° or more and less than 10 The case of "B-" and less than 5 ° was evaluated as "C". The evaluation results are shown in Table 1.

[Heat evaluation]
The cured film for evaluation was baked at 270 ° C. for 1 hour, and the shape change was visually confirmed. The case where the shape change was not substantially confirmed was evaluated as “A”, the case where the shape change was confirmed as “B”, and the case where the shape change was largely confirmed as “C”. The evaluation results are shown in Table 1.

  As shown in Table 1, when each composition of Examples 1 to 13 was used, a cured film having high optical density (OD) and reflectance was obtained, and the pattern formability was also good. That is, according to each composition of Examples 1-12, it turns out that the cured film which makes a high light reflection function and a fine pattern shape compatible can be formed.

  The photosensitive composition for display element formation can be used as a formation material of the structural member of a display element, and can be used suitably as a formation material of the partition of an organic EL element or a micro LED element especially.

Claims (13)

(A) White pigment,
(B) Alkali-soluble resin,
(C) polymerizable compounds,
A photosensitive composition for forming a display element, which comprises (D) a photopolymerization initiator, and (E) a solvent,
The photosensitive composition for display element formation whose content of said (A) white pigment is 30-90 mass%, when the component whole quantity except the (E) solvent is 100 mass%. (F) further containing a surfactant,
The display according to claim 1, wherein at least one selected from the group consisting of (B) an alkali soluble resin, (C) a polymerizable compound, and (F) a surfactant contains a Si atom or a F atom. Photosensitive composition for element formation.   The photosensitive composition for display element formation of Claim 1 or Claim 2 in which (B) alkali-soluble resin contains Si atom or F atom. The photosensitive composition for display element formation of Claim 3 in which (B) alkali-soluble resin contains group represented by 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, n is an integer of 1 to 10. n is 2 or more. In some cases, a plurality of R ¹ may be the same or different, and a plurality of R ² may be the same or different. * Represents a binding site.) (B) The alkali-soluble resin contains a structural unit having a group represented by the above formula (1),
The photosensitive composition for display element formation of Claim 4 whose content of the said structural unit is 1-70 mass% with respect to 100 mass% of (B) alkali-soluble resin.   The photosensitivity for forming a display element according to any one of claims 1 to 5, wherein the (B) alkali-soluble resin contains at least one selected from the group consisting of a carboxyl group and a phenolic hydroxyl group. Composition.   The alkali-soluble resin (B) according to any one of claims 1 to 6, wherein at least one selected from the group consisting of (meth) acryloyl, vinyl, oxiranyl and oxetanyl is included. The photosensitive composition for display element formation as described.   The photosensitive composition for display element formation of any one of Claim 1 thru | or 7 whose ring structure is contained in (B) alkali-soluble resin.   (A) The white pigment is at least one 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 The photosensitive composition for display element formation of any one of Claims 1 thru | or 8 containing.   The cured film formed using the photosensitive composition for display element formation of any one of Claims 1 thru | or 9.   The cured film according to claim 10, wherein the optical density (OD) is 0.2 to 5.0 / μm.   The cured film according to claim 10 or 11, wherein the contact angle of the surface to propylene glycol monomethyl ether acetate is 15 ° or more. A display element which is an organic EL element or a micro LED element having a partition,
The display element whose said partition is a cured film of any one of Claims 10 thru | or 12.