JP2024039205A - Resin composition and display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin composition which can prevent oxidation of a copper wire in manufacturing a display device with a light-emitting diode and a substrate connected together by a copper wire.

SOLUTION: In the display device with a light-emitting diode and a substrate connected together by a copper wire, the resin composition is used to provide an insulation layer between the light-emitting diode and the substrate. The oxygen transmittance of a cured film with a thickness of 10 μm obtained by curing the resin composition, measured by an electrolyte sensor technique of JIS K 7126-2, is 0.5-20 cc.mm/(m².day).

SELECTED DRAWING: Figure 1

COPYRIGHT: (C)2024,JPO&INPIT

Description

The present invention relates to a resin composition and a display device. More specifically, the present invention relates to a resin composition preferably used for manufacturing display devices such as liquid crystal displays, and a display device including a cured product of this resin composition.

Various techniques have been developed for resin compositions such as photosensitive resin compositions due to their industrial importance. For example, it is known to use a resin composition that has the property of being cured by light irradiation to form an insulating layer in an electronic device or a display device.

Examples of prior art for resin compositions include the following.
Patent Document 1 describes a photosensitive resin composition that includes a phenol resin having a biphenol structure and is used for forming a surface protective film or an interlayer insulating film of a semiconductor device.
Patent Document 2 describes a rewiring layer provided on the surface of a semiconductor chip using a negative photosensitive resin composition containing an epoxy resin, a phenoxy resin, and a photoacid generator, but not containing a phenol resin. It is described that an insulating layer is provided inside.

International Publication No. 2018/088469 International Publication No. 2020/045311

The present inventors discovered that in order to provide an insulating layer between a light emitting diode and a substrate in manufacturing a display device (such as a liquid crystal display) having a structure in which the light emitting diode and the substrate are connected by copper wiring, A resin composition was applied.
However, it has been found that when an insulating layer is provided using a conventional resin composition, there is a problem in that the copper wiring is oxidized.

The present invention has been made in view of these circumstances. One of the objects of the present invention is to provide a resin composition that can suppress oxidation of copper wiring in manufacturing a display device having a structure in which a light emitting diode and a substrate are connected by copper wiring. be.

The present inventors completed the invention provided below and solved the above problems.

1.
A resin composition used for providing an insulating layer between the light emitting diode and the substrate in a display device having a structure in which a light emitting diode and a substrate are connected by copper wiring, the resin composition comprising:
The oxygen permeability of a cured film with a thickness of 10 μm obtained by curing the resin composition as measured by the electrolytic sensor method of JIS K 7126-2 is 0.5 to 20 cc・mm/(m ²・day). A resin composition.
2.
1. The resin composition described in
A resin composition that is photosensitive.
3.
1. or 2. The resin composition described in
A resin composition containing any resin selected from the group consisting of polyimide, polyimide precursor, polybenzoxazole, and polybenzoxazole precursor.
4.
1. or 2. The resin composition described in
A resin composition containing an epoxy resin.
5.
1. or 2. The resin composition described in
A resin composition containing a phenolic resin.
6.
1. ~5. The resin composition according to any one of
The resin composition, wherein the cured film has a water vapor permeability of 0.1 to 5 g·mm/(m ² ·day) as measured by an infrared sensor method.
7.
A display device having a structure in which a light emitting diode and a substrate are connected by copper wiring,
Between the light emitting diode and the substrate, 1. ~6. A display device provided with an insulating layer that is a cured product of the resin composition according to any one of the above.

According to the present invention, in manufacturing a display device having a structure in which a light emitting diode and a substrate are connected by a copper wiring, it is possible to suppress oxidation of the copper wiring.

FIG. 3 is a diagram for explaining a method of manufacturing a display device. FIG. 3 is a diagram for explaining a method of manufacturing a display device. FIG. 3 is a diagram for explaining a method of manufacturing a display device.

Embodiments of the present invention will be described in detail below with reference to the drawings.
In all the drawings, similar components are denoted by the same reference numerals, and description thereof will be omitted as appropriate.
To avoid complication, (i) if there are multiple identical components in the same drawing, only one of them will be given a reference numeral and not all of them, or (ii) especially 2 and subsequent parts, components similar to those in FIG. 1 may not be labeled again.
All drawings are for illustrative purposes only. The shapes and dimensional ratios of each member in the drawings do not necessarily correspond to the actual product.

In the present specification, the notation "X to Y" in the description of numerical ranges refers to not less than X and not more than Y, unless otherwise specified. For example, "1 to 5% by mass" means "1 to 5% by mass".

In the description of a group (atomic group) in this specification, a description that does not indicate whether it is substituted or unsubstituted includes both those without a substituent and those with a substituent. For example, the term "alkyl group" includes not only an alkyl group without a substituent (unsubstituted alkyl group) but also an alkyl group having a substituent (substituted alkyl group).
In this specification, the expression "(meth)acrylic" represents a concept that includes both acrylic and methacrylic. The same applies to similar expressions such as "(meth)acrylate".
The term "organic group" as used herein means an atomic group obtained by removing one or more hydrogen atoms from an organic compound, unless otherwise specified. For example, a "monovalent organic group" refers to an atomic group obtained by removing one hydrogen atom from an arbitrary organic compound.

<Resin composition>
The resin composition of this embodiment is used to provide an insulating layer between the light emitting diode and the substrate in a display device having a structure in which the light emitting diode and the substrate are connected by copper wiring.
The oxygen permeability of the cured film with a thickness of 10 μm obtained by curing the resin composition of the present embodiment is 0.5 to 20 cc·mm/(m ²・day).
Incidentally, the oxygen permeability is preferably 0.5 to 15 cc·mm/(m ² ·day), more preferably 0.5 to 10 cc·mm/(m ² ·day). The "electrolytic sensor method" is described in detail in "Annex A" of JIS K 7126-2.
The resin composition of this embodiment is preferably photosensitive. In other words, the resin composition of this embodiment is preferably one that can be patterned by changing its solubility in a developer upon exposure to light.

As mentioned above, the oxygen permeability of the cured film of the resin composition of this embodiment is relatively small, 20 cc·mm/(m ² ·day) or less. In a display device, oxidation of the copper wiring is suppressed by covering the copper wiring with such a cured film with low oxygen permeability (the copper wiring no longer comes into direct contact with air). This also leads to longer lifespan and improved reliability of the display device.

The resin composition of this embodiment is particularly preferably used when manufacturing a display device using a light emitting diode called mini LED or micro LED, which is smaller in size than conventional ones. When using small-sized light emitting diodes, the copper wiring inevitably becomes thinner. In conventional display devices, oxidation of copper wiring was not a big problem because the copper wiring was thick enough, but even a small amount of oxidation can become a big problem in thin copper wiring to which mini LEDs and micro LEDs are connected. . Since the resin composition of the present embodiment can well suppress oxidation of copper wiring, it is preferably used for manufacturing display devices (typically liquid crystal displays) using mini LEDs and micro LEDs.

The resin composition of this embodiment can be manufactured by selecting appropriate materials and selecting appropriate manufacturing conditions. If appropriate materials and manufacturing conditions are not selected, the resin composition of this embodiment (which has a relatively low oxygen permeability when formed into a cured film) may not be manufactured.
Regarding the "appropriate material", it is possible to mention preferably the use of any one of several resins described below. Further, regarding "appropriate manufacturing conditions", it is preferable to prepare the resin composition under a nitrogen atmosphere.

Hereinafter, the resin composition of this embodiment will be explained in more detail.

(Example 1 of resin composition: Embodiment containing any resin selected from the group consisting of polyimide, polyimide precursor, polybenzoxazole, and polybenzoxazole precursor)
The resin composition of this embodiment can contain any resin selected from the group consisting of polyimide, polyimide precursor, polybenzoxazole, and polybenzoxazole precursor. Hereinafter, aspects of such a resin composition will be explained.
Here, "any resin selected from the group consisting of polyimide, polyimide precursor, polybenzoxazole, and polybenzoxazole precursor" may be referred to as "polyimide, etc." Further, the polyimide precursor and the polybenzoxazole precursor are sometimes referred to as "polyamide resin."

The resin composition containing polyimide etc. contains at least polyimide etc., and preferably has a photoinitiator, a urea derivative, an azole compound, a hindered phenol compound, an organic titanium compound, a sensitizer, and a photopolymerizable unsaturated bond. Contains one or more of monomers, adhesion aids, thermal polymerization inhibitors, crosslinking agents, solvents, etc.

- Polyimide etc. The polyimide preferably contains a structural unit represented by the following general formula (PI-1).

In general formula (PI-1),
X is a divalent organic group,
Y is a tetravalent organic group.

The divalent organic group of X and/or the tetravalent organic group of Y preferably contains an alicyclic structure or an aromatic ring structure, and more preferably contains a benzene ring structure. This tends to further improve heat resistance.
From the viewpoint of organic solvent solubility, one or both of X and Y may be a fluorine atom-containing group. On the other hand, from the viewpoint of reducing oxygen permeability, it is preferable that X and Y do not contain fluorine atoms.
The divalent organic group of X and/or the tetravalent organic group of Y preferably has a structure in which 2 to 6 alicyclic or aromatic rings are bonded via a single bond or a divalent linking group. . Examples of the divalent linking group here include an alkylene group, a fluorinated alkylene group, and an ether group. The alkylene group and fluorinated alkylene group may be linear or branched.
The divalent organic group of X has, for example, 6 to 30 carbon atoms.
The number of carbon atoms in the tetravalent organic group of Y is, for example, 6 to 20.
Each of the two imide rings in general formula (PI-1) is preferably a 5-membered ring.

More preferably, the polyimide contains a structural unit represented by the following general formula (PI-2).

In general formula (PI-2),
X has the same meaning as X in general formula (PI-1),
Y' represents a single bond or an alkylene group.

Specific embodiments of X are the same as those explained in general formula (PI-1).
The alkylene group of Y' may be linear or branched. The alkylene group of Y' has, for example, 1 to 6 carbon atoms, preferably 1 to 4 carbon atoms, and more preferably 1 to 3 carbon atoms.

Polyimide can be obtained by subjecting a polyimide precursor to a ring-closing reaction. As the polyimide precursor, a polyamide resin (specifically described below) can be used.

The weight average molecular weight of the polyimide and/or polyimide precursor is, for example, 5,000 to 100,000, preferably 7,000 to 75,000, more preferably 10,000 to 50,000. When the weight average molecular weight of the polyimide and/or the polyimide precursor is relatively high, for example, sufficient heat resistance of the cured film can be obtained. Furthermore, since the weight average molecular weight of the polyimide and/or polyimide precursor is not too large, it becomes easy to dissolve the polyimide and/or the polyimide precursor in an organic solvent.
The weight average molecular weight can usually be determined by gel permeation chromatography (GPC) using polystyrene as a standard substance.

It is preferable that the polybenzoxazole contains a structural unit represented by the following general formula (PB01). When using polybenzoxazole, only one benzoxazole resin may be used, or two or more polybenzoxazole resins may be used in combination.

Polybenzoxazole can be obtained by subjecting a polybenzoxazole precursor to a ring-closing reaction. A polyamide resin can be used as the polybenzoxazole precursor.

The polyamide resin preferably contains a structural unit represented by the following general formula (PA-1). When using a polyamide resin, only one polyamide resin may be used, or two or more polyamide resins may be used in combination.

In general formula (PA-1), the definitions and specific embodiments of X and Y are the same as in general formula (PI-1).

More preferably, the polyamide resin contains a structural unit represented by the following general formula (PA-2).

In general formula (PA-2),
X has the same meaning as X in general formula (PA-1),
Y' represents a single bond or an alkylene group.

- Photoinitiator When making the resin composition photosensitive, the resin composition can contain a photoinitiator.
Examples of photoinitiators include benzophenone, methyl o-benzoylbenzoate, 4-benzoyl-4'-methyldiphenylketone, dibenzylketone, benzophenone derivatives such as fluorenone, 2,2'-diethoxyacetophenone, 2-hydroxy -2-Methylpropiophenone, acetophenone derivatives such as 1-hydroxycyclohexylphenyl ketone, thioxanthone, thioxanthone derivatives such as 2-methylthioxanthone, 2-isopropylthioxanthone, diethylthioxanthone, benzyl, benzyl dimethyl ketal, benzyl-β-methoxyethyl Benzyl derivatives such as acetal, benzoin, benzoin derivatives such as benzoin methyl ether, 1-phenyl-1,2-butanedione-2-(o-methoxycarbonyl)oxime, 1-phenyl-1,2-propanedione-2-( o-methoxycarbonyl)oxime, 1-phenyl-1,2-propanedione-2-(o-ethoxycarbonyl)oxime, 1-phenyl-1,2-propanedione-2-(o-benzoyl)oxime, 1, Oximes such as 3-diphenylpropanetrione-2-(o-ethoxycarbonyl)oxime and 1-phenyl-3-ethoxypropanetrione-2-(o-benzoyl)oxime, N-arylglycines such as N-phenylglycine , peroxides such as benzoyl perchloride, and aromatic biimidazoles. Of course, usable photoinitiators are not limited to these. Only one photoinitiator may be used or two or more photoinitiators may be used in combination. From the viewpoint of photosensitivity, oximes are preferred as photoinitiators.

When a photoinitiator is used, the amount thereof is usually 1 to 20 parts by weight, and preferably 2 to 15 parts by weight from the viewpoint of photosensitivity characteristics, based on 100 parts by weight of polyimide or the like.

-Urea derivatives By using urea derivatives, it may be possible to obtain effects such as improving the sensitivity and stability of the composition and suppressing discoloration of copper.
Examples of urea derivatives include 1,3-dimethylurea, 1,3-dimethylthiourea, 1,3-dimethylolurea, 1,3-dimethylolthiourea, 1,3-dimethoxymethylurea, 1,3-dimethoxy Methylthiourea, 1,3-diethylurea, 1,3-diethylthiourea, 1,3-diisopropylurea, 1,3-diisopropylthiourea, 1,3-di-n-propylurea, 1,3-di-n -Propylthiourea, 1,3-dibutylurea, 1,3-dibutylthiourea, 1,3-bis(2-methylpropyl)urea, 1,3-bis(2-methylpropyl)thiourea, 1,3-bis (1-methylpropyl)urea, 1,3-bis(1-methylpropyl)thiourea, 1,3-dicyclopentylurea, 1,3-dicyclopentylthiourea, 1,3-di-n-pentylurea, 1,3-di-n-pentylthiourea, 1,3-bis(1-methylbutyl)urea, 1,3-bis(1-methylbutyl)thiourea, 1,3-bis(2-methylbutyl)urea, 1, 3-bis(2-methylbutyl)thiourea, 1,3-bis(3-methylbutyl)urea, 1,3-bis(3-methylbutyl)thiourea, 1,3-bis(1-ethylpropyl)urea, 1 ,3-bis(1-ethylpropyl)thiourea, 1,3-dicyclohexylurea, 1,3-dicyclohexylthiourea, 1,3-diphenylurea, 1,3-diphenylthiourea, 1,3-dihydroxyethylurea , 1,3-dihydroxyethylthiourea, 1,3-di(4-pyridyl)urea, 1,3-di(4-pyridyl)thiourea, 1,3-di(3-pyridyl)urea, 1,3 -di(3-pyridyl)thiourea, 1,3-di(2-pyridyl)urea, 1,3-di(2-pyridyl)thiourea, 1-adamantyl-3-phenylurea, 1-adamantyl-3- Phenylthiourea, 1,3-di(o-tolyl)urea, 1,3-di(o-tolyl)thiourea, 1,3-di(p-tolyl)urea, 1,3-di(p-tolyl) Thiourea, 1-methyl-3-ethylurea, 1-methyl-3-ethylthiourea, 1-methyl-3-n-propylurea, 1-methyl-3-n-propylthiourea, 1-methyl-3-isopropyl Urea, 1-methyl-3-isopropylthiourea, 1-methyl-3-(2-methylbutyl)urea, 1-methyl-3-(2-methylbutyl)thiourea, 1-methyl-3-(1-methylbutyl) Urea, 1-methyl-3-(1-methylbutyl)thiourea, 1-methyl-3-n-pentylurea, 1-methyl-3-n-pentylthiourea, 1-methyl-3-n-butylurea, 1 -Methyl-3-n-butylthiourea, 1-methyl-3-n-hexylurea, 1-methyl-3-n-hexylthiourea, 1-methyl-3-cyclohexylurea, 1-methyl-3-cyclohexylthiourea , 1,3-bis(3,5-dimethylphenyl)urea, 1,3-bis(3,5-dimethylphenyl)thiourea, 1,3-bis(3-methoxypropyl)urea, 1,3-bis (3-methoxypropyl)thiourea, 1-methyl-3-benzylurea, 1-methyl-3-benzylthiourea, 1,3-dibenzylurea, 1,3-dibenzylthiourea, 1-ethyl-3-n-propyl Urea, 1-ethyl-3-n-propylthiourea, 1-ethyl-3-isopropylurea, 1-ethyl-3-isopropylthiourea, 1-ethyl-3-(2-methylbutyl)urea, 1-ethyl-3 -(2-methylbutyl)thiourea, 1-ethyl-3-(1-methylbutyl)urea, 1-ethyl-3-(1-methylbutyl)thiourea, 1-ethyl-3-n-pentylurea, 1-ethyl -3-n-pentylthiourea, 1-ethyl-3-n-butylurea, 1-ethyl-3-n-butylthiourea, 1-ethyl-3-n-hexylurea, 1-ethyl-3-n-hexylthio Urea, 1-ethyl-3-cyclohexylurea, 1-ethyl-3-cyclohexylthiourea, 1-methyl-3-(3,5-dimethylphenyl)urea, 1-methyl-3-(3,5-dimethylphenyl) ) Thiourea, 1-ethyl-3-(3,5-dimethylphenyl)urea, 1-ethyl-3-(3,5-dimethylphenyl)thiourea, 1-methyl-3-acetylurea, 1-methyl- Examples include 3-acetylthiourea.

Considering the balance of various performances, the amount when using a urea derivative is usually 0.1 to 30 parts by weight, preferably 0.1 to 20 parts by weight, based on 100 parts by weight of polyimide or the like.

・Azole compounds By using azole compounds, it may be possible to further suppress copper oxidation and discoloration. As the azole compound, a compound having a triazole structure or a compound having a tetrazole structure is preferable, and a compound having a triazole structure is more preferable.

Specific examples of azole compounds include 1H-triazole, 5-methyl-1H-triazole, 5-ethyl-1H-triazole, 4,5-dimethyl-1H-triazole, 5-phenyl-1H-triazole, 4-t- Butyl-5-phenyl-1H-triazole, 5-hydroxyphenyl-1H-triazole, phenyltriazole, p-ethoxyphenyltriazole, 5-phenyl-1-(2-dimethylaminoethyl)triazole, 5-benzyl-1H-triazole , hydroxyphenyltriazole, 1,5-dimethyltriazole, 4,5-diethyl-1H-triazole, 1H-benzotriazole, 2-(5-methyl-2-hydroxyphenyl)benzotriazole, 2-[2-hydroxy-3 ,5-bis(α,α-dimethylbenzyl)phenyl]-benzotriazole, 2-(3,5-di-t-butyl-2-hydroxyphenyl)benzotriazole, 2-(3-t-butyl-5- Methyl-2-hydroxyphenyl)-benzotriazole, 2-(3,5-di-t-amyl-2-hydroxyphenyl)benzotriazole, 2-(2'-hydroxy-5'-t-octylphenyl)benzotriazole , hydroxyphenylbenzotriazole, tolyltriazole, 5-methyl-1H-benzotriazole, 4-methyl-1H-benzotriazole, 4-carboxy-1H-benzotriazole, 5-carboxy-1H-benzotriazole, 1H-tetrazole, 5 -Methyl-1H-tetrazole, 5-phenyl-1H-tetrazole, 5-amino-1H-tetrazole, 1-methyl-1H-tetrazole and the like.

The amount of the azole compound added is usually 0.1 to 20 parts by weight, and preferably 0.5 to 5 parts by weight from the viewpoint of photosensitivity characteristics, per 100 parts by weight of polyimide or the like.

・Hindered phenol compound By using a hindered phenol compound, discoloration and oxidation of copper may be further suppressed. Hindered phenol compound refers to a compound in which the carbon atom adjacent to the carbon atom to which the oxygen atom of the hydroxyl group is bonded in the aromatic ring of the phenol compound has a bulky substituent such as a t-butyl group. .

Examples of hindered phenol compounds include 2,6-di-t-butyl-4-methylphenol, 2,5-di-t-butyl-hydroquinone, octadecyl-3-(3,5-di-t-butyl -4-hydroxyphenyl)propionate, isooctyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, 4,4'-methylenebis(2,6-di-t-butylphenol), 4,4'-thio-bis(3-methyl-6-t-butylphenol), 4,4'-butylidene-bis(3-methyl-6-t-butylphenol), triethylene glycol-bis[3-(3 -t-butyl-5-methyl-4-hydroxyphenyl)propionate], 1,6-hexanediol-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 2,2 -thio-diethylenebis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], N,N'hexamethylenebis(3,5-di-t-butyl-4-hydroxy-hydro) cinnamamide), 2,2'-methylene-bis(4-methyl-6-t-butylphenol), 2,2'-methylene-bis(4-ethyl-6-t-butylphenol), pentaerythrityl-tetrakis [3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], tris-(3,5-di-t-butyl-4-hydroxybenzyl)-isocyanurate, 1,3,5 -trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene, 1,3,5-tris(3-hydroxy-2,6-dimethyl-4-isopropylbenzyl) )-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl )-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-s-butyl-3-hydroxy-2,6-dimethylbenzyl )-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris[4-(1-ethylpropyl)-3-hydroxy-2,6 -dimethylbenzyl]-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris[4-triethylmethyl-3-hydroxy-2,6- dimethylbenzyl]-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(3-hydroxy-2,6-dimethyl-4-phenylbenzyl )-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-3-hydroxy-2,5,6- trimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-5-ethyl-3-hydroxy- 2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-6-ethyl- 3-Hydroxy-2-methylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-6- Ethyl-3-hydroxy-2,5-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t- Butyl-5,6-diethyl-3-hydroxy-2-methylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris( 4-t-butyl-3-hydroxy-2-methylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4- t-Butyl-3-hydroxy-2,5-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4- Examples include t-butyl-5-ethyl-3-hydroxy-2-methylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione. Of course, the hindered phenol compounds that can be used are not limited to these.
Among them, 1,3,5-tris(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)- Trion and the like are particularly preferred.

When using a hindered phenol compound, the amount is usually 0.1 to 20 parts by weight, and preferably 0.5 to 10 parts by weight from the viewpoint of photosensitivity characteristics, based on 100 parts by weight of polyimide or the like.

- Organic titanium compounds The use of organic titanium compounds may improve chemical resistance, etc.
The organic titanium compound is not particularly limited as long as it has an organic chemical substance bonded to a titanium atom via a covalent bond or an ionic bond.

Specific examples of organic titanium compounds are shown in I) to VII) below.

I) Titanium chelate compound: Among them, titanium chelate having two or more alkoxy groups is more preferable because it provides stability of the composition and a good pattern. Specifically, titanium bis(triethanolamine) diisopropylene Poxide, titanium di(n-butoxide) bis(2,4-pentanedionate), titanium diisopropoxide bis(2,4-pentanedionate), titanium diisopropoxide bis(tetramethylheptanedioate), Titanium diisopropoxide bis(ethyl acetoacetate), etc.

II) Tetraalkoxytitanium compounds: for example, titanium tetra(n-butoxide), titanium tetraethoxide, titanium tetra(2-ethylhexoxide), titanium tetraisobutoxide, titanium tetraisopropoxide, titanium tetramethoxide , titanium tetramethoxypropoxide, titanium tetramethyl phenoxide, titanium tetra(n-nonyloxide), titanium tetra(n-propoxide), titanium tetrastearyloxide, titanium tetrakis[bis{2,2-(allyloxymethyl)] butoxide}], etc.

III) Titanocene compounds: for example, pentamethylcyclopentadienyl titanium trimethoxide, bis(η ⁵ -2,4-cyclopentadien-1-yl)bis(2,6-difluorophenyl)titanium, bis(η ⁵ - 2,4-cyclopentadien-1-yl)bis(2,6-difluoro-3-(1H-pyrrol-1-yl)phenyl)titanium and the like.

IV) Monoalkoxytitanium compounds: For example, titanium tris(dioctyl phosphate) isopropoxide, titanium tris(dodecylbenzenesulfonate) isopropoxide, and the like.

V) Titanium oxide compound: For example, titanium oxide bis(pentanedionate), titanium oxide bis(tetramethylheptanedionate), phthalocyanine titanium oxide, etc.

VI) Titanium tetraacetylacetonate compound: For example, titanium tetraacetylacetonate.

VII) Titanate coupling agent: for example, isopropyl tridodecyl benzenesulfonyl titanate.
Among these, at least one compound selected from the group consisting of I) titanium chelate compounds, II) tetraalkoxytitanium compounds, and III) titanocene compounds is preferred from the viewpoint of better chemical resistance.

When using an organic titanium compound, the amount is preferably 0.05 to 10 parts by weight, more preferably 0.1 to 2 parts by weight, based on 100 parts by weight of polyimide or the like.

- Sensitizer A sensitizer can be optionally added to improve photosensitivity. Examples of the sensitizer include Michler's ketone, 4,4'-bis(diethylamino)benzophenone, 2,5-bis(4'-diethylaminobenzal)cyclopentane, 2,6-bis(4'-diethylaminobenzal) Cyclohexanone, 2,6-bis(4'-diethylaminobenzal)-4-methylcyclohexanone, 4,4'-bis(dimethylamino)chalcone, 4,4'-bis(diethylamino)chalcone, p-dimethylaminocinnamyl Denindanone, p-dimethylaminobenzylideneindanone, 2-(p-dimethylaminophenylbiphenylene)-benzothiazole, 2-(p-dimethylaminophenylvinylene)benzothiazole, 2-(p-dimethylaminophenylvinylene)iso Naphthothiazole, 1,3-bis(4'-dimethylaminobenzal)acetone, 1,3-bis(4'-diethylaminobenzal)acetone, 3,3'-carbonyl-bis(7-diethylaminocoumarin), 3 -Acetyl-7-dimethylaminocoumarin, 3-ethoxycarbonyl-7-dimethylaminocoumarin, 3-benzyloxycarbonyl-7-dimethylaminocoumarin, 3-methoxycarbonyl-7-diethylaminocoumarin, 3-ethoxycarbonyl-7-diethylaminocoumarin Coumarin, N-phenyl-N'-ethylethanolamine, N-phenyldiethanolamine, N-p-tolyldiethanolamine, N-phenylethanolamine, 4-morpholinobenzophenone, isoamyl dimethylaminobenzoate, isoamyl diethylaminobenzoate, 2-mercapto Benzimidazole, 1-phenyl-5-mercaptotetrazole, 2-mercaptobenzothiazole, 2-(p-dimethylaminostyryl)benzoxazole, 2-(p-dimethylaminostyryl)benzthiazole, 2-(p-dimethylaminostyryl) ) naphtho(1,2-d)thiazole, 2-(p-dimethylaminobenzoyl)styrene, and the like. These may be used alone or in combination of two or more.

When using a sensitizer, the amount thereof is preferably 0.1 to 25 parts by weight per 100 parts by weight of polyimide or the like.

- Monomer having a photopolymerizable unsaturated bond In order to improve the resolution of the pattern, a monomer having a photopolymerizable unsaturated bond can be optionally added. As such a monomer, a (meth)acrylic compound that undergoes a radical polymerization reaction with a photopolymerization initiator is preferable, and examples include, but are not limited to, ethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, etc. or mono- or di-acrylates and methacrylates of polyethylene glycol, mono- or di-acrylates and methacrylates of propylene glycol or polypropylene glycol, mono-, di- or triacrylates and methacrylates of glycerol, cyclohexane diacrylates and dimethacrylates, di-methacrylates of 1,4-butanediol. Acrylates and dimethacrylates, diacrylates and dimethacrylates of 1,6-hexanediol, diacrylates and dimethacrylates of neopentyl glycol, mono- or diacrylates and methacrylates of bisphenol A, benzene trimethacrylate, isobornyl acrylate and methacrylate, acrylamide and derivatives thereof, methacrylamide and derivatives thereof, trimethylolpropane triacrylate and methacrylate, di- or triacrylate and methacrylate of glycerol, di-, tri-, or tetraacrylate and methacrylate of pentaerythritol, and ethylene oxide or propylene oxide addition of these compounds. Examples include compounds such as . These may be used alone or in combination of two or more.

When using a monomer having a photopolymerizable unsaturated bond, the amount thereof is preferably 1 to 50 parts by weight based on 100 parts by weight of polyimide or the like.

・Adhesion aid An adhesion aid can be optionally added to improve adhesion with the substrate. Specifically, γ-aminopropyldimethoxysilane, N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-mercaptopropylmethyldimethoxysilane, 3-methacrylate Roxypropyldimethoxymethylsilane, 3-methacryloxypropyltrimethoxysilane, dimethoxymethyl-3-piperidinopropylsilane, diethoxy-3-glycidoxypropylmethylsilane, N-(3-diethoxymethylsilylpropyl)succinimide, N-[3-(triethoxysilyl)propyl]phthalamic acid, benzophenone-3,3'-bis(N-[3-triethoxysilyl]propylamide)-4,4'-dicarboxylic acid, benzene-1,4 - Silane coupling agents such as bis(N-[3-triethoxysilyl]propylamide)-2,5-dicarboxylic acid, 3-(triethoxysilyl)propyl succinic anhydride, N-phenylaminopropyltrimethoxysilane, etc. , aluminum tris (ethyl acetoacetate), and aluminum tris (acetylacetonate).
Also included are aluminum-based adhesion aids such as ethyl acetoacetate aluminum diisopropylate.
When using adhesion aids, only one adhesion aid or two or more adhesion aids may be used.

From the viewpoint of good adhesion, it is more preferable to use a silane coupling agent as the adhesion aid.
When using an adhesion aid, the amount thereof is preferably 0.5 to 25 parts by weight per 100 parts by weight of polyimide or the like.

- Thermal polymerization inhibitor By using a thermal polymerization inhibitor, it may be possible to improve the stability of the viscosity and photosensitivity of the resin composition solution during storage.
Thermal polymerization inhibitors include hydroquinone, N-nitrosodiphenylamine, p-tert-butylcatechol, phenothiazine, N-phenylnaphthylamine, ethylenediaminetetraacetic acid, 1,2-cyclohexanediaminetetraacetic acid, glycol etherdiaminetetraacetic acid, 2,6 -di-tert-butyl-p-methylphenol, 5-nitroso-8-hydroxyquinoline, 1-nitroso-2-naphthol, 2-nitroso-1-naphthol, 2-nitroso-5-(N-ethyl-N- Sulfopropylamino)phenol, N-nitroso-N-phenylhydroxylamine ammonium salt, N-nitroso-N(1-naphthyl)hydroxylamine ammonium salt, etc. are used. When using a thermal polymerization inhibitor, only one thermal polymerization inhibitor may be used, or two or more thermal polymerization inhibitors may be used.
When a thermal polymerization inhibitor is used, the amount thereof is preferably 0.005 to 12 parts by mass per 100 parts by mass of polyimide or the like.

・Crosslinking agent When heat curing the pattern, a crosslinking agent that can crosslink polyimide or the like or itself can form a crosslinked network can be added to further strengthen the heat resistance and chemical resistance of the cured film. .
As the crosslinking agent, amino resins or derivatives thereof are preferably used. Among them, glycol urea resin, hydroxyethylene urea resin, melamine resin, benzoguanamine resin, or derivatives thereof are preferably used. Particularly preferred are alkoxymethylated melamine compounds, such as hexamethoxymethylmelamine.
When a crosslinking agent is used, the amount thereof is preferably 2 to 40 parts by weight, more preferably 5 to 30 parts by weight, based on 100 parts by weight of polyimide or the like.

-Solvent The resin composition is usually one in which the above-mentioned polyimide or the like is dissolved or dispersed in a solvent. As the solvent, an organic solvent is usually used.
From the viewpoint of solubility in polyimide and the like, it is preferable to use a polar organic solvent as the solvent. Specifically, N,N-dimethylformamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N,N-dimethylacetamide, dimethyl sulfoxide, diethylene glycol dimethyl ether, cyclopentanone, γ-butyrolactone, α -acetyl-γ-butyrolactone, tetramethylurea, 1,3-dimethyl-2-imidazolinone, N-cyclohexyl-2-pyrrolidone and the like.
Only one type of solvent may be used, or two or more types may be used in combination.

The amount of solvent used may be adjusted as appropriate depending on the desired coating film thickness and viscosity of the resin composition. As an example, the solvent can be used in an amount of, for example, 30 to 1,500 parts by mass based on 100 parts by mass of polyimide or the like.

(Example 2 of resin composition: Embodiment containing epoxy resin)
As a different aspect from Example 1 above, the resin composition of this embodiment can preferably contain an epoxy resin. Hereinafter, an embodiment in which the resin composition contains an epoxy resin will be described.

A resin composition containing an epoxy resin contains at least an epoxy resin, and preferably also contains a phenoxy resin, a photoacid generator, a surfactant, other additives, a solvent, and the like.

-Epoxy resin As the epoxy resin, for example, an epoxy resin having two or more epoxy groups in one molecule can be used. As the epoxy resin, monomers, oligomers, and polymers in general can be used, and the molecular weight and molecular structure thereof are not particularly limited.
Examples of the epoxy resin include phenol novolac type epoxy resin, cresol novolac type epoxy resin, cresol naphthol type epoxy resin, biphenyl type epoxy resin, biphenylaralkyl type epoxy resin, naphthalene skeleton type epoxy resin, bisphenol A type epoxy resin, and bisphenol A type epoxy resin. diglycidyl ether type epoxy resin, bisphenol F type epoxy resin, bisphenol F diglycidyl ether type epoxy resin, bisphenol S diglycidyl ether type epoxy resin, glycidyl ether type epoxy resin, cresol novolak type epoxy resin, aromatic polyfunctional epoxy resin, Examples include aliphatic epoxy resins, aliphatic polyfunctional epoxy resins, alicyclic epoxy resins, and polyfunctional alicyclic epoxy resins. Epoxy resins may be used alone or in combination.

Epoxy resins can include solid epoxy resins having two or more epoxy groups in the molecule. As the solid epoxy resin, one that has two or more epoxy groups and is solid at 25° C. (room temperature) can be used. Thereby, the mechanical properties of the resin film of the resin composition can be improved.

Further, the epoxy resin can include a polyfunctional epoxy resin having three or more functionalities in its molecule (that is, a polyfunctional epoxy resin having three or more epoxy groups in one molecule).

Examples of trifunctional or higher polyfunctional epoxy resins include phenol novolac epoxy resins, cresol novolak epoxy resins, triphenylmethane epoxy resins, dicyclopentadiene epoxy resins, bisphenol A epoxy resins, and tetramethylbisphenol F. It is preferable to include one or more epoxy resins selected from the group consisting of type epoxy resins, and more preferably a novolac type epoxy resin. This makes it possible to achieve an appropriate coefficient of thermal expansion while increasing the heat resistance of the resin film.

Further, the epoxy resin can include a liquid epoxy resin having two or more epoxy groups in the molecule. The liquid epoxy resin functions as a film-forming agent and can improve the brittleness of the resin film of the resin composition.

As the liquid epoxy resin, it is possible to use an epoxy compound that has two or more epoxy groups and is liquid at room temperature of 25°C. The viscosity of this liquid epoxy resin at 25°C is, for example, 1 mPa·s to 8000 mPa·s, preferably 5 mPa·s to 1500 mPa·s, and more preferably 10 mPa·s to 1400 mPa·s. .

The liquid epoxy resin may include, for example, one or more selected from the group consisting of bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, alkyl diglycidyl ether, and alicyclic epoxy. These may be used alone or in combination of two or more. Among these, alkyl diglycidyl ethers can be used from the viewpoint of reducing cracks after development.

The epoxy equivalent of the liquid epoxy resin is, for example, 100 g/eq or more and 200 g/eq or less, preferably 105 g/eq or more and 180 g/eq or less, and more preferably 110 g/eq or more and 170 g/eq or less. Thereby, the brittleness of the resin film can be improved.

The lower limit of the content of the liquid epoxy resin is, for example, 5% by mass or more, preferably 10% by mass or more, and more preferably 15% by mass or more, based on the total nonvolatile components of the resin composition. Thereby, the brittleness of the cured film finally obtained can be improved. On the other hand, the upper limit of the content of the liquid epoxy resin is, for example, 40% by mass or less, preferably 35% by mass or less, and more preferably 30% by mass or less, based on the total nonvolatile components of the resin composition. Thereby, the film properties of the cured film can be balanced.

The lower limit of the content of the epoxy resin is, for example, 40% by mass or more, preferably 45% by mass or more, and more preferably 50% by mass or more, based on the total nonvolatile components of the resin composition. Thereby, the heat resistance and mechanical strength of the cured film finally obtained can be improved. On the other hand, the upper limit of the content of the epoxy resin is, for example, 90% by mass or less, preferably 85% by mass or less, and more preferably 82% by mass or less, based on the total nonvolatile components of the resin composition. Thereby, patterning properties can be improved.

The weight average molecular weight (Mw) of the epoxy resin is not particularly limited, but is preferably from 300 to 9,000, more preferably from 500 to 8,000. By using an epoxy resin with a relatively low molecular weight, reactivity during exposure can be increased.

- Phenoxy resin When the resin composition contains a phenoxy resin, the flexibility of the resin film of the resin composition can be increased.

The weight average molecular weight (Mw) of the phenoxy resin is not particularly limited, but is preferably from 10,000 to 100,000, more preferably from 20,000 to 80,000. By using such a phenoxy resin having a relatively high molecular weight, it is possible to impart good flexibility to the resin film as well as sufficient solubility in a solvent. The weight average molecular weight is measured as a polystyrene equivalent value using gel permeation chromatography (GPC), for example.

Further, the phenoxy resin may have a reactive group such as an epoxy group at both ends of the molecular chain or within the molecular chain. The reactive group in the phenoxy resin is capable of crosslinking with the epoxy group in the epoxy resin. By using such a phenoxy resin, the solvent resistance and heat resistance in the resin film can be improved.

Moreover, as the phenoxy resin, one that is solid at 25° C. is preferably used. Specifically, a phenoxy resin having a nonvolatile content of 90% by mass or more is preferably used. By using such a phenoxy resin, the mechanical properties of the cured product can be improved.

Examples of the phenoxy resin include bisphenol A type phenoxy resin, bisphenol F type phenoxy resin, copolymerized phenoxy resin of bisphenol A type and bisphenol F type, biphenyl type phenoxy resin, bisphenol S type phenoxy resin, biphenyl type phenoxy resin and bisphenol. Examples include copolymerized phenoxy resins with S-type phenoxy resins, and one or a mixture of two or more of these may be used. Among these, bisphenol A type phenoxy resin or copolymerized phenoxy resin of bisphenol A type and bisphenol F type is preferably used.

The lower limit of the content of the phenoxy resin is, for example, 10 parts by mass or more, preferably 13 parts by mass or more, and more preferably 15 parts by mass or more, based on 100 parts by mass of the epoxy resin. Thereby, patterning properties can be improved. Furthermore, flexibility can be increased. On the other hand, the upper limit of the content of the phenoxy resin is, for example, 60 parts by mass or less, preferably 50 parts by mass or less, more preferably 40 parts by mass or less, based on 100 parts by mass of the epoxy resin content. Thereby, an increase in moisture absorption rate can be suppressed and heat resistance reliability can be improved. Moreover, the solubility of the phenoxy resin is increased, and a resin composition with excellent coating properties can be realized. Note that the reference epoxy resin may be a trifunctional or higher polyfunctional epoxy resin.

- Photoacid generator The resin composition can contain a photoacid generator. When the resin composition contains a photoacid generator, the resin composition becomes photosensitive. Then, patterning becomes possible through selective exposure and subsequent development processing. The resin composition is preferably a chemically amplified photosensitive resin composition that uses an acid generated from a photoacid generator as a catalyst, and can be a negative photosensitive resin composition.

Examples of photoacid generators include onium salt compounds. More specifically, iodonium salts such as diazonium salts and diaryliodonium salts, sulfonium salts such as triarylsulfonium salts, triarylbyrylium salts, benzylpyridinium thiocyanate, dialkylphenacylsulfonium salts, and dialkylhydroxyphenylphosphonium salts. Examples include cationic photopolymerization initiators. Among these, triarylsulfonium salts can be used from the viewpoint of patterning properties.

As the counter anion of the onium salt compound, a borate anion, a sulfonate anion, a gallate anion, a phosphorus anion, an antimony anion, etc. are used.

When using a photoacid generator, the amount thereof is, for example, 0.3 to 5.0% by mass, preferably 0.5 to 4.5% by mass, more preferably 1.5% by mass, based on the total solid content of the resin composition. It is 0 to 4.0% by mass. By setting it to the above lower limit or more, patterning properties can be improved. On the other hand, by setting it below the above-mentioned lower limit, insulation reliability can be improved.

-Surfactant When the resin composition contains a surfactant, wettability during coating can be improved and a uniform resin film and cured film can be obtained. Examples of the surfactant include fluorine surfactants, silicone surfactants, alkyl surfactants, and acrylic surfactants.

The surfactant preferably contains a surfactant containing at least one of a fluorine atom and a silicon atom. This contributes to obtaining a uniform resin film (improving coating properties), improving developability, and improving adhesive strength. As such a surfactant, for example, a nonionic surfactant containing at least one of a fluorine atom and a silicon atom is preferable. Commercially available products that can be used as surfactants include, for example, F-251, F-253, F-281, F-430, F-477, F-551 of the "Megafac" series manufactured by DIC Corporation. F-552, F-553, F-554, F-555, F-556, F-557, F-558, F-559, F-560, F-561, F-562, F-563, F- 565, F-568, F-569, F-570, F-572, F-574, F-575, F-576, R-40, R-40-LM, R-41, R-94, etc. Fluorine-containing surfactants with oligomer structure, fluorine-containing nonionic surfactants such as Ftergent 250 and Ftergent 251 manufactured by Neos Co., Ltd., SILFOAM (registered trademark) series manufactured by Wacker Chemie (for example, SD 100 TS) , SD 670, SD 850, SD 860, SD 882) and the like.

The content of the surfactant can be, for example, 0.001 to 1% by mass, preferably 0.005 to 0.5% by mass, based on the total amount of nonvolatile components of the resin composition.

-Adhesion aid When the resin composition contains an adhesion aid, the adhesion to an inorganic material such as a substrate can be further improved.

The adhesion aid is not particularly limited, but for example, silane coupling agents such as aminosilane, epoxysilane, acrylicsilane, mercaptosilane, vinylsilane, ureidosilane, sulfidesilane, and acid anhydride-containing silane can be used. One type of silane coupling agent may be used alone, or two or more types may be used in combination. Among these, it is more preferable to use epoxysilane (that is, a compound containing both an epoxy moiety and a group that generates a silanol group by hydrolysis in one molecule).

Examples of amino group-containing coupling agents include bis(2-hydroxyethyl)-3-aminopropyltriethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, and γ-aminopropylmethyldiethoxysilane. , γ-aminopropylmethyldimethoxysilane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane, N-β (aminoethyl) γ-aminopropyltriethoxysilane, N-β (aminoethyl) γ-aminopropyl Examples include methyldimethoxysilane, N-β(aminoethyl)γ-aminopropylmethyldiethoxysilane, and N-phenyl-γ-amino-propyltrimethoxysilane.
Examples of the epoxy group-containing coupling agent include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidylpropyl Examples include trimethoxysilane.
Examples of the acrylic group-containing coupling agent or the methacrylic group-containing coupling agent include γ-(methacryloxypropyl)trimethoxysilane, γ-(methacryloxypropyl)methyldimethoxysilane, and γ-(methacryloxypropyl)methyldiethoxysilane. etc.
Examples of the mercapto group-containing coupling agent include 3-mercaptopropyltrimethoxysilane.
Examples of the vinyl group-containing coupling agent include vinyltris(β-methoxyethoxy)silane, vinyltriethoxysilane, and vinyltrimethoxysilane.
Examples of the ureido group-containing coupling agent include 3-ureidopropyltriethoxysilane.
Examples of the sulfide group-containing coupling agent include bis(3-(triethoxysilyl)propyl)disulfide, bis(3-(triethoxysilyl)propyl)tetrasulfide, and the like.
Examples of the acid anhydride-containing coupling agent include 3-trimethoxysilylpropylsuccinic anhydride, 3-triethoxysilylpropylsuccinic anhydride, 3-dimethylmethoxysilylpropylsuccinic anhydride, and the like.

Although silane coupling agents are listed here, titanium coupling agents, zirconium coupling agents, etc. may also be used.

The content of the adhesion aid is preferably 0.3 to 5% by mass, more preferably 0.4 to 4%, and 0.5 to 3% by mass based on the total amount of nonvolatile components of the resin composition. Mass % is more preferred.

- Additives In addition to the above-mentioned components, other additives may be added to the resin composition as necessary. Other additives include, for example, antioxidants, fillers such as silica, sensitizers, film-forming agents, and the like.

-Solvent The resin composition can contain a solvent. An organic solvent can be included as the solvent. The organic solvent can be used without particular limitation as long as it can dissolve each component of the resin composition and does not chemically react with each component.

Examples of organic solvents include acetone, methyl ethyl ketone, toluene, propylene glycol methyl ethyl ether, propylene glycol dimethyl ether, propylene glycol 1-monomethyl ether 2-acetate, diethylene glycol ethyl methyl ether, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, and benzyl. Examples include alcohol, propylene carbonate, ethylene glycol diacetate, propylene glycol diacetate, propylene glycol monomethyl ether acetate, dipropylene glycol methyl-n-propyl ether, butyl acetate, and γ-butyrolactone. These may be used alone or in combination.

The solvent is preferably used so that the total concentration of nonvolatile components in the resin composition is, for example, 30 to 75% by mass. By setting it as this range, each component can be fully dissolved and good applicability can be ensured. Furthermore, by adjusting the content of nonvolatile components, the viscosity of the resin composition can be appropriately controlled.

The viscosity of the resin composition at 25° C. is, for example, 10 to 6000 cP, preferably 20 to 5000 cP, and more preferably 30 to 4000 cP. By controlling the viscosity within the above numerical range, the thickness of the coating film can be appropriately controlled.

(Example 3 of resin composition: Embodiment containing phenolic resin)
As an aspect different from Examples 1 and 2 above, the resin composition of this embodiment can preferably contain a phenol resin. Hereinafter, an embodiment in which the resin composition contains a phenol resin will be described.

A resin composition containing a phenol resin contains at least a phenol resin, and preferably contains a photoacid generator, a solvent, a crosslinking agent, a silane coupling agent, a surfactant, a reaction accelerator, and the like.

- Phenol resin Phenol resin usually has a structural unit derived from a phenol compound and at least one compound selected from the group consisting of aldehyde compounds, dimethylol compounds, dimethoxymethyl compounds, and dihaloalkyl compounds. In other words, the phenolic resin is obtained by reacting a phenol compound with at least one compound selected from the group consisting of aldehyde compounds, dimethylol compounds, dimethoxymethyl compounds, and dihaloalkyl compounds.

In the resin composition of this embodiment, it is preferable to use a biphenol compound as the phenol compound. Thereby, the phenol resin will have a biphenol structure. Biphenol compounds include 2,2'-biphenol and 4,4'-biphenol, and isomers thereof. These biphenol compounds may have a substituent, and examples of the substituent include a hydroxyl group, a halogen, a carboxyl group, a saturated or unsaturated alkyl group having 1 to 20 carbon atoms, and an alkyl ether having 1 to 20 carbon atoms. group, a saturated or unsaturated alicyclic group having 3 to 20 carbon atoms, or an organic group having an aromatic structure having 6 to 20 carbon atoms.

Phenolic resins can be manufactured by any known method. Examples of the production method include a condensation reaction between a phenol compound and an aldehyde compound, dimethylol compound, dimethoxymethyl compound, or dihaloalkyl compound.

The weight average molecular weight (in terms of polystyrene) of the phenol resin is, for example, in the range of 1,000 to 100,000, preferably in the range of 2,000 to 50,000, and more preferably in the range of 3,000 to 30,000. A phenol resin having a weight average molecular weight within the above range has excellent solubility in a solvent and the resulting resin film has excellent mechanical properties.

- Photoacid generator When making the resin composition photosensitive, a photoacid generator can be used.
A photoacid generator is a compound that generates acid in response to irradiated radiation. The photoacid generator is preferably a compound that generates an acid upon irradiation with radiation having a wavelength of 200 to 500 nm, particularly preferably 350 to 450 nm. Specific examples include photosensitive diazoquinone compounds, photosensitive diazonaphthoquinone compounds, onium salts such as diaryliodonium salts, triarylsulfonium salts or sulfonium borate salts, 2-nitrobenzyl ester compounds, N-iminosulfonate compounds, imidosulfonate compounds. , 2,6-bis(trichloromethyl)-1,3,5-triazine compound, dihydropyridine compound and the like. These may be used alone or in combination of two or more. Among these, photosensitive diazoquinone compounds and photosensitive diazonaphthoquinone compounds, which are excellent in sensitivity and solvent solubility, are preferred. Specific examples of these include phenol compounds such as 1,2-benzoquinonediazide-4-sulfonic acid ester, 1,2-naphthoquinonediazide-4-sulfonic acid ester, and 1,2-naphthoquinonediazide-5-sulfonic acid ester. Can be mentioned.

When a photoacid generator is used, it is used in an amount of, for example, 1 to 100 parts by weight, preferably 3 to 50 parts by weight, based on 100 parts by weight of the phenolic resin.

-Solvent The resin composition of this embodiment is used in the form of a varnish obtained by dissolving the above components in a solvent. The solvents used include N-methyl-2-pyrrolidone, γ-butyrolactone, N,N-dimethylacetamide, dimethyl sulfoxide, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, Propylene glycol monomethyl ether acetate, methyl lactate, ethyl lactate, butyl lactate, methyl-1,3-butylene glycol acetate, 1,3-butylene glycol-3-monomethyl ether, methyl pyruvate, ethyl pyruvate and methyl-3-methoxy Examples include organic solvents such as propionate.
The solvent may be used alone or in combination of two or more solvents.

The amount of the solvent used is usually 50 to 1000 parts by weight, preferably 100 to 500 parts by weight, per 1000 parts by weight of the phenolic resin. By using a solvent within the above range, it is possible to produce a varnish with excellent handling properties in which the resin is sufficiently dissolved.

-Crosslinking agent The crosslinking agent has a group that can react with the phenol resin. When a resin film is prepared using a resin composition containing a crosslinking agent, patterned by exposure and development, and then heated and cured, the crosslinking agent is phenol-generated by the acid generated from the photoacid generator or by the action of heat. Crosslinks with resin.

As the crosslinking agent, it is preferable to use a compound that can be thermally crosslinked with a phenol resin. Crosslinking agents that can be used include the following compounds:
(1) A compound containing one or more crosslinkable groups selected from the group consisting of a methylol group and an alkoxymethyl group.
(2) A compound having an epoxy group.
(3) A compound having an isocyanate group.
(4) Compounds having a bismaleimide group.

When a crosslinking agent is used, the amount thereof is usually 1 to 100 parts by weight, preferably 5 to 50 parts by weight, based on 100 parts by weight of the phenolic resin.

- Silane coupling agent When the resin composition contains a silane coupling agent, the adhesion of the resin film to the substrate is improved. Examples of the silane coupling agent include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropyl Methyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, N-2-(aminoethyl)- 3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, bis(triethoxypropyl)tetrasulfide, 3-isocyanatepropyltri Examples include ethoxysilane and silicon compounds obtained by reacting a silicon compound having an amino group with an acid dianhydride or an acid anhydride. Of course, the silane coupling agent is not limited to these. Silane coupling agents can be used alone or in combination of two or more.

When using a silane coupling agent, the amount thereof is usually 0.1 to 30 parts by weight, preferably 1 to 20 parts by weight, based on 100 parts by weight of the phenolic resin. By using the silane coupling agent within the above range, it is possible to achieve both adhesion to the substrate and storage stability of the resin composition.

-Surfactant By using a surfactant, the coating property when applying the resin composition onto a base material to obtain a resin film becomes good.
As the surfactant, nonionic surfactants are preferred. In particular, as the nonionic surfactant, fluorine-based surfactants or silicone-based surfactants are more preferred, and fluorine-based surfactants are even more preferred. Examples of fluorine-based surfactants include Megafac F-171, F-173, F-444, F-470, F-471, F-475, F-482, F-477, and F-554 manufactured by DIC Corporation. , F-556, and F-557, and Novec FC4430 and FC4432 manufactured by 3M. Of course, usable surfactants are not limited to these.

When a surfactant is used, the amount of the surfactant blended is preferably 0.01 to 10 parts by mass based on 100 parts by mass of the phenol resin.

-Reaction accelerator By using a reaction accelerator, thermal crosslinking between the phenol resin and the crosslinking agent contained in the resin composition can be promoted. As the reaction accelerator, for example, a nitrogen-containing five-membered heterocyclic compound or a compound that generates an acid when heated can be used. These may be used alone or in combination. Examples of the nitrogen-containing five-membered heterocyclic compound used as a reaction accelerator include pyrrole, pyrazole, imidazole, 1,2,3-triazole, and 1,2,4-triazole. Further, examples of compounds that generate an acid by heat and are used as reaction accelerators include sulfonium salts, iodonium salts, sulfonates, phosphates, borates, and salicylates. From the viewpoint of more effectively improving the curability at low temperatures, it is more preferable to include one or both of sulfonates and borates among compounds that generate acids when heated, to improve the heat resistance of the cured film properties. In view of this, it is particularly preferred to include borates.

・Other additives In addition to the above ingredients, additives such as solubility promoters, antioxidants, fillers, photopolymerization initiators, terminal capping agents, sensitizers, etc. may be added as necessary to impair the effects of the present invention. It may be further used within the range.

(About water vapor permeability)
By designing the resin composition so that the water vapor permeability of the cured film is low, oxidation of the copper wiring can be further suppressed.
Specifically, the water vapor permeability of a 10 μm thick cured film obtained by curing the resin composition as measured by an infrared sensor method is preferably 0.1 to 5 g·mm/(m ² ·day). , more preferably 0.1 to 4 g·mm/(m ² ·day), still more preferably 0.1 to 3 g·mm/(m ² ·day).

(Supplementary information regarding oxygen permeability and water vapor permeability)
As already mentioned, in this embodiment, since the cured film with a thickness of 10 μm obtained by curing the resin composition has appropriate oxygen permeability and water vapor permeability, copper wiring can be used in the manufacture of display devices. It is possible to suppress the oxidation of
Here, the method of curing the resin composition to obtain a "cured film with a thickness of 10 μm" is not particularly limited. Based on past knowledge and taking into account the reactivity of the resin composition to heat and light, the curing conditions (heating temperature and time, temperature and time of heating, whether the composition is photosensitive, In some cases, the exposure conditions may be set. Then, the resin composition may be cured based on the set curing conditions to obtain a cured film having a thickness of 10 μm. As far as the present inventors have found, as long as the resin composition is sufficiently cured (not in a semi-cured state) within the range of normally employable curing conditions, the cured product of the resin composition may be affected by differences in curing conditions. The oxygen permeability and water vapor permeability of the material remain virtually unchanged.
For examples of curing conditions that may be employed, see the Examples below.

(About the manufacturing method of resin composition)
The resin composition of this embodiment is preferably prepared under a nitrogen atmosphere. Specifically, it is preferable to perform the step of dissolving or dispersing each component such as a resin and a photosensitizer in an organic solvent under a nitrogen atmosphere. Although the details are unknown, by preparing the resin composition under a nitrogen atmosphere, the amount of nitrogen in the composition becomes relatively large, and the amount of oxygen in the composition becomes relatively small. By reducing the amount of oxygen in the composition, oxidation and decomposition of the components in the composition when heating and curing the composition is suppressed, resulting in an oxygen permeability of 0.5 to 20 cc/mm. /(m ² ·day) It is thought that it becomes easier to obtain a cured film.

<Display device and its manufacturing method>
As described above, the resin composition of the present embodiment is used to provide an insulating layer between the light emitting diode and the substrate in a display device having a structure in which the light emitting diode and the substrate are connected by copper wiring. .
Hereinafter, an example of a method for manufacturing a display device and a structure of the display device when the resin composition is photosensitive will be described with reference to the drawings.

(Figure 1(a))
First, a substrate 1 is prepared. Substrate 1 is usually a transparent substrate such as glass. Structures such as circuits may be formed on the substrate 1 as necessary. That is, the board 1 may be a circuit board.

(Figure 1(b))
A photosensitive resin film 3A is formed on the substrate 1 using a resin composition.
The method of film formation is not particularly limited. In terms of efficiently coating a large area, film formation by an inkjet method is preferable. In addition to the inkjet method, various coating methods such as spin coating, bar coating, and curtain coating can be used. Various printing methods other than the inkjet method can also be employed.
After applying the resin composition onto the substrate 1, heat treatment (prebaking) may be performed. The conditions for this can be, for example, 60 to 140° C. and about 30 to 600 seconds.
The thickness of the photosensitive resin film 3A is usually 1 to 20 μm, specifically 3 to 15 μm. It is preferable to adjust the coating conditions and the viscosity of the resin composition so as to achieve this thickness.

(Figure 1(c))
The pattern 3B is formed by selectively applying light to the photosensitive resin film 3A (exposure) and then performing a development process using a developer.
For selective exposure, exposure is typically performed using a photomask (not shown).
As the active light for exposure, for example, X-rays, electron beams, ultraviolet rays, visible light, etc. can be used, and those having a wavelength of 200 to 500 nm are preferable. In terms of pattern resolution and ease of handling, the light source wavelength is preferably in the g-line, h-line, or i-line region of a mercury lamp.
The amount of light irradiation may be adjusted as appropriate based on the sensitivity of the resin composition.

The photosensitive resin film 3A may be heated after exposure and before development (post-exposure heating). The heating conditions can be, for example, 80 to 140° C. for about 10 to 300 seconds.

The development process can be carried out, for example, by a dipping method, a paddle method, a rotary spray method, or the like. By development, the exposed portion (in the case of positive type) or the unexposed portion (in the case of negative type) is eluted and removed from the photosensitive resin film 3A, and pattern 3B can be obtained.

The developer is typically (i) an aqueous alkaline solution or (ii) an organic solvent. The developer can be appropriately selected depending on the design of the resin composition.
Examples of (i) include inorganic alkalis such as sodium hydroxide, sodium carbonate, sodium silicate, and ammonia; organic amines such as ethylamine, diethylamine, triethylamine, and triethanolamine; tetramethylammonium hydroxide, and tetrabutylammonium hydroxide. Examples include aqueous solutions of quaternary ammonium salts such as
Examples of (ii) include cyclopentanone, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, butyl acetate, and methyl amyl ketone.
Naturally, developers not listed here can also be used as long as they can pattern the photosensitive resin film 3A.

After the development process, a rinsing process may be performed to remove fine residues and residual developer. Regarding the rinsing process, known techniques can be appropriately referred to.

From the viewpoint of resistance to sputtering, which will be described later, it is preferable to heat-cure the pattern 3B. The heating temperature at this time is preferably 150°C to 500°C, more preferably 150°C to 400°C. The heating time can be 15 to 300 minutes. This heat treatment can be performed using a hot plate, an oven, a heating oven in which a temperature program can be set, or the like. The atmospheric gas during the heat treatment may be air or an inert gas such as nitrogen or argon. If it is necessary to perform heat treatment at a low temperature, heating may be performed under reduced pressure using a vacuum pump or the like.

(Figure 1(d))
Preferably, the metal-containing layer 5 is formed on the thermoset pattern 3B by a suitable means such as sputtering. The metal-containing layer 5 can be, for example, a metal, a metal oxide, a metal nitride, or the like. The metal-containing layer 5 serves as a "base" and "foundation" to which copper adheres in a copper plating process to be described later.
The thickness of the metal-containing layer 5 is, for example, 50 to 1000 nm, preferably 100 to 500 nm.

(Figure 1(e))
A pattern 7 is further provided on the pattern 3B provided with the metal-containing layer 5. Pattern 7, like pattern 3B, can be provided through processes such as coating, exposing, developing, and thermosetting a resin composition. As the resin composition for providing the pattern 7, a known resin composition (such as a resist composition) can be used as appropriate. Since the pattern 7 is peeled off and removed in a process described later, it is preferable to use a resin composition that has a property of being easily removed after patterning.
By appropriately controlling the shapes and positions of the patterns 3B and 7, desired copper wiring can be obtained in the steps described below.

(Figure 2(f))
Copper plating is performed on the structure in which pattern 3B, metal-containing layer 5, and pattern 7 are formed. As a result, copper wiring 9 is provided.
Copper plating may be wet plating or dry plating. In this embodiment, wet plating is preferred, and more specifically electrolytic plating is preferred.

(Figure 2(g))
Remove pattern 7. For example, the pattern 7 is removed by using a stripping liquid capable of stripping the pattern 7.
Further, after removing the pattern 7, the portion of the metal-containing layer 5 where the pattern 7 was formed is removed. This exposes a portion of pattern 3B. For removing the metal-containing layer 5, for example, a dry etching method using a gas that can selectively etch the metal-containing layer 5 can be applied.

(Figure 2(h))
Again, using the resin composition, a pattern is formed by coating, exposure, development, and other treatments. As a result, a further pattern is formed on the pattern 3B formed in FIG. 1(c), resulting in a new pattern 3B.
At this time, a pattern 3B is formed so as to expose a part of the copper wiring 9. In other words, the opening of the pattern 3B is provided above the copper wiring 9. This is for electrically connecting the copper wiring 9 and the LED element in a process described later.

The resin composition used here is the resin composition of this embodiment described above. The resin composition of this embodiment used here may be the same as or different from the resin composition used in FIG. 1(b) as long as the oxygen permeability when formed into a cured film is low. However, from the viewpoint of making the physical properties of the newly formed pattern as a whole uniform, it is preferable that the resin composition used here and the resin composition used in FIG. 1(b) are the same.

A specific method for pattern formation here can be performed as described with reference to FIG. 1(c). Therefore, explanation regarding the specific method of pattern formation will be omitted.

(Figure 2(i))
Copper wiring 9 is provided at least in the opening of pattern 3B. Specifically, a copper wiring 9 is further provided on the copper wiring 9 provided in FIG. 2(f) to form a new copper wiring 9.
The method of providing the copper wiring 9 here can refer to the method explained in FIG. 1(d) to FIG. 2(g). That is, the copper wiring 9 can be provided by steps such as forming a metal-containing layer by appropriate means such as sputtering, forming a pattern using a peelable and removable resin composition, copper plating, and removing the pattern.

(Figure 2(j))
An LED element 11 is mounted on the copper wiring 9. For example, the LED element 11 is electrically connected to the copper wiring 9 by soldering.
The LED element 11 is not particularly limited as long as it can be used in a display device. Depending on the configuration of the display device, the LED element 11 may be a white LED, or may be an LED that emits red, green, or blue light.

The LED element 11 may be a micro LED or a mini LED. Micro LED refers to an LED whose chip size is less than 100 μm square. A mini LED refers to an LED with a chip size of 100 μm or more (more specifically, 100 μm or more and 200 μm or less). Micro LEDs and mini LEDs are LEDs that typically emit red, green, or blue light, and display devices using these LED elements are classified as so-called "self-luminous" types.

Please refer to the following documents for information on what micro LEDs and mini LEDs are.
2019 Latest trend survey of next-generation display technology and related materials/processes (Fuji Chimera Research Institute)
Journal of the Institute of Image Information and Media Studies Vol. 73, No. 5, pp. 939-942 (2019)

As mentioned above, even if a small LED element such as a micro LED or mini LED is used as the LED element 11 and the copper wiring 9 is thinned for that purpose, the composition for forming the pattern 3B may be used. By using the resin composition of this embodiment, oxidation of the copper wiring 9 can be suppressed.

(Figure 3(k), Figure 3(l) and Figure 3(m))
A display device is manufactured by sequentially providing the protective layer 13, the adhesive layer 15, and the cover layer 17. Regarding materials for providing these layers and specific methods for providing these layers, known techniques can be appropriately referred to.

As described above, a structure is provided in which the light emitting diode (LED element 11) and the substrate (substrate 1) are electrically connected by the copper wiring (copper wiring 9), and the light emitting diode and the substrate are connected electrically. A display device with an insulating layer (pattern 3B) provided therebetween can be manufactured.

(Supplementary information when the resin is non-photosensitive)
In FIGS. 1 to 3, the case where the resin composition is photosensitive and can be patterned by exposure and development has been described.
If the resin composition is non-photosensitive and patterning cannot be performed with the resin composition alone, the process shown in Figures 1 to 3 can be achieved by supplementarily using another photosensitive resin composition (photoresist). It is possible to implement a similar process. Specifically, a process similar to the above process is carried out by "patterning" a resin film formed from a non-photosensitive resin composition through the steps (i) to (v) below. be able to.
(i) Forming a resin film using a resin composition (ii) Forming a photoresist film on the resin film (iii) Forming a pattern by exposing and developing the photoresist (iv) Using the formed pattern as a mask Pattern the resin film by etching it (v) Peel off the photoresist

Although the embodiments of the present invention have been described above, these are merely examples of the present invention, and various configurations other than those described above can be adopted. Furthermore, the present invention is not limited to the above-described embodiments, and the present invention includes modifications, improvements, etc. within a range that can achieve the purpose of the present invention.

Embodiments of the present invention will be described in detail based on Examples and Comparative Examples. It should be noted that the present invention is not limited only to the embodiments.

<Example 1: Preparation of resin composition (non-photosensitive) containing polyimide precursor>
A resin composition (non-photosensitive) containing a polyimide precursor was prepared by the following procedure. All of the following procedures were performed under a nitrogen atmosphere.
(1) 0.93 mol of 4,4'-diaminodiphenyl ether and 0.07 mol of APDS (3-aminopyridyl-N-hydroxysuccinimidyl carbamate) were dissolved in 3310 g of N-methyl-2-pyrrolidone with stirring. A solution was prepared.
(2) After adding 0.71 mol of pyromellitic dianhydride and 0.31 mol of benzophenonetetracarboxylic acid to the above solution, the mixture was reacted at 80° C. for 3 hours.
(3) The viscosity was adjusted by appropriately adjusting the amount of solvent based on the evaluation described below (forming a film with a thickness of 10 μm).

<Example 2: Preparation of photosensitive resin composition containing phenolic resin>
(resin synthesis)
186.2 g (1.00 mol) of 4,4'-biphenol and 2,6-bis were placed in a four-neck glass round-bottomed flask equipped with a thermometer, stirrer, raw material inlet, and dry nitrogen gas inlet. 134.6 g (0.8 mol) of (hydroxymethyl)-p-cresol, 6.3 g (0.05 mol) of oxalic acid dihydrate, and 327 g of γ-butyrolactone were charged.
Thereafter, a polycondensation reaction was carried out at 100° C. for 6 hours while refluxing the reaction solution in the round bottom flask in an oil bath while flowing nitrogen.
Next, the obtained reaction solution was cooled to room temperature.
Thereafter, 436 g of acetone was added and mixed with stirring until uniform.
Thereafter, the reaction solution in the round bottom flask was added dropwise to 10 L of water to precipitate the resin component.
Next, the precipitated resin component was collected by filtration.
Thereafter, vacuum drying was performed at 60° C. to obtain a phenol resin represented by the following formula (A-1). In formula (A-1), the bond bonded to the biphenol structure is bonded to one of the two benzene rings. The weight average molecular weight of the obtained phenol resin (A-1) was 9,800.

(Preparation of photosensitive resin composition)
A photosensitive resin composition was prepared by uniformly mixing the following components under a nitrogen atmosphere.
- The above phenolic resin: 100 parts by mass - Additive Crolin-318 (manufactured by Daito Chemix): 15 parts by mass - Additive YX7105 (manufactured by Mitsubishi Chemical): 15 parts by mass - Photosensitizer DS-427 (manufactured by Daito Chemix): 27 Parts by mass / Thermal acid generator SI-B5 (manufactured by Sanshin Kagakusha): 5 parts by mass / Solvent γ-butyrolactone: 205 parts by mass / Surfactant Fluorine surfactant manufactured by 3M Corporation FC4432: Based on the entire composition 200ppm

<Example 3: Preparation of photosensitive resin composition containing polyimide precursor>
(resin synthesis)
Put 428 g of γ-butyrolactone, 155.11 g of 4,4'-oxydiphthalic dianhydride, and 130.14 g of 2-hydroxyethyl methacrylate into a 2 L separable flask, and stir the components in the flask at room temperature to completely dissolve them. Ta. Subsequently, 79.1 g of pyridine was added while stirring at room temperature, and the mixture was further stirred at room temperature for 16 hours.

While cooling and stirring the solution obtained above under ice cooling, a solution of 206.3 g of dicyclohexylcarbodiimide dissolved in 206 g of γ-butyrolactone was added to the solution over 30 minutes. Subsequently, 120.1 g of 4,4'-diaminodiphenyl ether and 240 g of γ-butyrolactone were added, and stirring was continued for an additional 2 hours at room temperature.
After the reaction was completed, 30 g of ethanol was added and stirred for 1 hour. Thereafter, 400 g of γ-butyrolactone was added and further stirred, and the resulting precipitate was removed by filtration. As a result, a polyamic acid ester reaction solution was obtained.
The obtained reaction solution was added dropwise to a large amount of 30% by mass methanol aqueous solution with stirring at room temperature to precipitate the resin. The obtained precipitate was collected by filtration and vacuum-dried to obtain a polyimide precursor.

(Preparation of photosensitive resin composition)
A photosensitive resin composition was prepared by uniformly mixing the following components under a nitrogen atmosphere.
- 100 parts by mass of the above polyimide precursor - 1-phenyl-1,2-propanedione-2-(O-ethoxycarbonyl)-oxime (photoinitiator)
6 parts by mass・1,3-dimethylolurea 1 part by mass・1 part by mass of benzotriazole・1,3,5-tris(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3, 5-triazine-2,4,6-(1H,3H,5H)-trione (hindered phenol compound) 1 part by mass / N-phenyldiethanolamine 10 parts by mass / Tetraethylene glycol dimethacrylate 8 parts by mass / N-[3 A mixed solvent consisting of 1.5 parts by mass of -(triethoxysilyl)propyl]phthalamic acid, 80 parts by mass of N-methyl-2-pyrrolidone (NMP), and 20 parts by mass of ethyl lactate.

The viscosity of the composition obtained by mixing the above was adjusted to about 35 poise by further adding a small amount of the above mixed solvent.

<Example 4: Preparation of photosensitive resin composition containing epoxy resin>
(Preparation of photosensitive resin composition)
A photosensitive resin composition was prepared by uniformly mixing the following components under a nitrogen atmosphere.
・Epoxy resin: Multifunctional epoxy resin represented by the following structure (EPPN201 manufactured by Nippon Kayaku Co., Ltd., phenol novolac type epoxy resin, solid at 25°C, n is approximately 5) 80.8 parts by mass

・Phenoxy resin: Bisphenol A type phenoxy resin (jER1256, manufactured by Mitsubishi Chemical Corporation, Mw: approximately 50,000)) 16.0 parts by mass ・Photoacid generator triarylsulfonium borate salt (manufactured by San-Apro, CPI-310B): 2.2 parts by mass・Surfactant Fluorinated group/lipophilic group-containing oligomer (R-41, manufactured by DIC Corporation): 0.2 parts by mass・Silane coupling agent 3-glycidoxypropyltrimethoxysilane (KBM- 403, manufactured by Shin-Etsu Chemical Co., Ltd.): 0.8 parts by mass

<Comparative Example 1: Preparation of photosensitive resin composition>
The photosensitive resin composition of Example 1 of JP-A-2021-162834 was prepared. Note that this preparation was performed under an air atmosphere.

<Comparative Example 2: Preparation of photosensitive resin composition>
(resin synthesis)
A resin was synthesized according to the description in paragraph 0157 [Synthesis Example 1] of JP-A-2021-152634. However, as the aminophenol, 2,2-bis(3-amino-4-hydroxyphenyl) described in paragraph 0129 of the same publication can be used instead of 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane. 32.25 g (125 mmol) of -hydroxyphenyl)propane was used.

(Preparation of photosensitive resin composition)
A photosensitive resin composition was prepared by uniformly mixing the following components. Note that this preparation was performed under an air atmosphere.
・Above resin: 100 parts by mass ・Crosslinking agent A-9550 (manufactured by Shin Nakamura Chemical Co., Ltd., mixture of compounds having 5 to 6 acryloyl groups: 10 parts by mass ・Sensitizer ADEKA Arkles NCI-730 (manufactured by ADEKA Corporation) , oxime ester type photoradical generator): 10 parts by mass, thermal radical generator Perkadox BC (manufactured by Kayaku Nourion Co., Ltd., organic peroxide, cumyl peroxide): 5 parts by mass, silane coupling agent X-12 -967C (manufactured by Shin-Etsu Chemical Co., Ltd.): 2 parts by mass / Surfactant FC4432 (manufactured by 3M, fluorine-based): 0.05 parts by mass / Solvent γ-butyrolactone: 550 parts by mass

<Measurement of oxygen permeability and water vapor permeability of cured film>
The oxygen permeability was measured according to the following procedure. Here, the curing conditions shown below and in Table 1 below are within the range of curing conditions that can be normally adopted depending on the characteristics of each composition (corresponding to any of Examples 1 to 3 above). This was determined by the inventors.

1. A resin composition was applied to a silicon wafer so that the thickness after drying was 10 μm to form a resin film. Application was performed by spin coating, and the film thickness was adjusted by appropriately changing the rotation speed.
2. When a negative photosensitive resin composition is used as the resin composition, the above 1. The resin film obtained was exposed using an i-ray stepper as described in "Exposure amount" in the table below (intended to be an exposure amount that causes the photosensitizer in the photosensitive resin composition to sufficiently react). Ta. In Example 4, heating was then further performed at the temperature and time described in "Post-exposure heating" in the table below.
3. Above 1. or 2. The resin film was heated at the temperature and for the time described in "Curing Conditions" in the table below, and then allowed to cool to room temperature. Heating was performed under a nitrogen atmosphere. In addition, in the table below, "150/30+320/30" in Example 1 means that after heating at 150°C for 30 minutes, heating was continued at 320°C for 30 minutes.
4. Above 3. The cured film obtained was immersed in hydrofluoric acid and peeled off. The peeled cured film was thoroughly washed with pure water and then air-dried.
5. Above 4. The oxygen permeability of the cured film obtained was measured under the following conditions.
Test standard: JIS K 7126-2 electrolytic sensor method Test equipment: MOCON oxygen permeation tester OX-TRAN 2/21
Temperature and humidity conditions: 23℃, 60%RH
Test room environment: 23±2℃, 50±5%RH
Transmission area: 5cm ² (using mask)
Permeation direction: Any Test gas: Air containing 21% oxygen

Water vapor permeability was measured using the following procedure.
Test standard: JIS K 7129-2 infrared sensor method Test equipment: MOCON water vapor permeation tester PERMATRAN W3/33
Temperature and humidity conditions: 40℃, 90%RH
Test room environment: 22±1℃, 55±5%RH
Transmission area: 5cm ² (using mask)
Transmission direction: Any

<Evaluation: Oxidation inhibiting ability of copper>
Instead of actually manufacturing a display device, a sample was created by coating a copper-plated wafer with a resin composition and providing a cured film. Then, by heating this sample, the extent to which the copper plating was oxidized was evaluated. Specifically, the evaluation was performed using the following procedure.

1. A copper plated wafer with a plating thickness of 2 μm was prepared.
2. A photosensitive resin composition was applied onto the wafer so as to have a predetermined thickness after drying to form a resin film. Application was performed by spin coating, and the film thickness was adjusted by appropriately changing the rotation speed.
3. When a negative photosensitive resin composition is used as the resin composition, the above 2. The resin film obtained was exposed using an i-ray stepper as described in "Exposure amount" in the table below (intended to be an exposure amount that causes the photosensitizer in the photosensitive resin composition to sufficiently react). Ta. In Example 4, heating was then further performed at the temperature and time described in "Post-exposure heating" in the table below.
4. Above 2. or 3. The resin film was heated at the temperature and time listed in the table below, and then allowed to cool to room temperature. Heating was performed under a nitrogen atmosphere. A sample for evaluation was thus obtained.
5. Above 4. The evaluation sample obtained in the above was placed in an oven set at 150° C. and heated in an air atmosphere for 500 hours. Thereafter, the sample was allowed to cool to room temperature.
6. Above 5. The cross section of the obtained sample was processed using a focused ion beam (FIB) to expose the cross section.
7. The cross section was observed using a field emission scanning electron microscope. Then, the thickness of the formed copper oxide film was measured. The smaller the thickness of the copper oxide film, the more suppressed is the oxidation of copper, that is, the more suppressed is the oxidation of the copper wiring in the display device.

Various information is summarized in the table below. Note that the water vapor permeability of Example 4 has not been measured.

As shown in the above table, copper oxidation could be suppressed by providing a cured film on a copper-plated wafer using a resin composition that had a low oxygen permeability when formed into a cured film. From this result, it was found that when the resin composition of this embodiment is used to provide an insulating layer between the light emitting diode and the substrate in a display device having a structure in which the light emitting diode and the substrate are connected by copper wiring. It is understood that oxidation of copper wiring can be suppressed.

1 Substrate 3A Photosensitive resin film 3B Pattern 5 Metal-containing layer 7 Pattern 9 Copper wiring 11 LED element 13 Protective layer 15 Adhesive layer 17 Cover layer

Claims (7)

A resin composition used for providing an insulating layer between the light emitting diode and the substrate in a display device having a structure in which a light emitting diode and a substrate are connected by copper wiring, the resin composition comprising:
The oxygen permeability of a cured film with a thickness of 10 μm obtained by curing the resin composition as measured by the electrolytic sensor method of JIS K 7126-2 is 0.5 to 20 cc・mm/(m ²・day). A resin composition. The resin composition according to claim 1,
A resin composition that is photosensitive. The resin composition according to claim 1 or 2,
A resin composition containing any resin selected from the group consisting of polyimide, polyimide precursor, polybenzoxazole, and polybenzoxazole precursor. The resin composition according to claim 1 or 2,
A resin composition containing an epoxy resin. The resin composition according to claim 1 or 2,
A resin composition containing a phenolic resin. The resin composition according to claim 1 or 2,
The resin composition, wherein the cured film has a water vapor permeability of 0.1 to 5 g·mm/(m ² ·day) as measured by an infrared sensor method. A display device having a structure in which a light emitting diode and a substrate are connected by copper wiring,
A display device, wherein an insulating layer that is a cured product of the resin composition according to claim 1 or 2 is provided between the light emitting diode and the substrate.

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