JP2019168624A - Photosensitive resin composition, photoresist film using the same, and method for forming resist pattern - Google Patents

Abstract

To provide a transparent photosensitive resin composition which has good resolution and exhibits less discoloration due to exposure.SOLUTION: The photosensitive resin composition contains a binder polymer (A), a photopolymerizable compound (B), and a photopolymerization initiator (C). The binder polymer (A) has an I/O value of 0.54-0.74. The photosensitive resin composition contains, as the photopolymerization initiator (C), a hexaarylbisimidazole-based initiator (C1) and an aminobenzenesulfonamide derivative (C2) represented by general formula (1) described in claim 1. The content of a leuco dye (D) is 0-0.05 pt.wt. based on 100 pts.wt. of the total amount of the binder polymer (A) and the photopolymerizable compound (B).SELECTED DRAWING: None

Description

  The present invention relates to a photosensitive resin composition that can be developed with an alkaline aqueous solution, a photoresist film comprising a photosensitive resin composition layer comprising the photosensitive resin composition, and a resist pattern formed on a substrate using the photoresist film. In particular, the present invention relates to a photosensitive resin composition from which a photosensitive resin composition layer excellent in resolution and transparency of a cured film can be obtained.

  Element display devices such as liquid crystal displays and touch panels (touch sensors) are used for large electronic devices such as personal computers and televisions, small electronic devices such as car navigation systems, mobile phones, and electronic dictionaries, and display devices such as OA devices and FA devices. It has been. For materials used for these display devices and touch panels, a material that efficiently transmits light emitted from a light source such as a backlight is required to ensure the visibility of the display unit.

  Further, the TN type liquid crystal display has a weak point that the manufacturing cost is lower than other type liquid crystal displays and the heat resistance is excellent, while the viewing angle is narrow. As a method for improving this, a structure in which a viewing angle widening film is incorporated in a display device has been proposed.

  The photosensitive resin composition used for this viewing angle widening film is required to have excellent resolution, high transmittance, and weather resistance. For example, in Patent Document 1, an ethylenically unsaturated group is contained in the photosensitive resin composition. A transparent photosensitive resin having a resolution of L / S (line / space) 10/10 (μm) has been proposed by containing three or more compounds. However, with an increase in the number of pixels of the display, the photosensitive resin composition is required to further improve the resolution.

  Patent Document 2 discloses a photosensitive resin composition using a specific photopolymerizable monomer having an amino group, and a photoresist film obtained using this photosensitive resin composition has a resolution. It is disclosed that it is excellent. However, since this photosensitive resin composition contains many leuco dyes as color formers in addition to colored dyes, color development occurs during exposure, making it difficult to adapt to display devices.

Japanese Patent Laying-Open No. 2015-152676 JP 2012-194552 A

  In view of the above situation, an object of the present invention is to provide a photosensitive resin composition having good resolution and less discoloration by exposure, and a photo including a photosensitive resin composition layer comprising the photosensitive resin composition. A resist film and a method for forming a resist pattern on a substrate using the photoresist film are provided.

However, as a result of intensive studies by the inventor in order to solve the above problems, a binder polymer having an I / O value within a predetermined range is used, and as a photopolymerization initiator, a hexaarylbisimidazole-based initiator, and By using a specific aminobenzenesulfonamide derivative in combination, it is possible to form a pattern with a high resolution of L / S = 10/10 (μm) or less, and a photosensitive resin composition with little discoloration difference before and after exposure. The inventors have found that the present invention can be obtained and have completed the present invention.
Further, by further using a hindered phenol-based inhibitor, weather resistance is improved, whitening and discoloration can be suppressed even after long-term use, and a photosensitive resin composition excellent in transparency and long-term reliability can be obtained. I also found.

That is, the photosensitive resin composition of the present invention is a photosensitive resin composition containing A) a binder polymer, (B) a photopolymerizable compound, and (C) a photopolymerization initiator,
The (A) binder polymer has an I / O value of 0.54 to 0.74,
As the (C) photopolymerization initiator, (C1) a hexaarylbisimidazole-based initiator, and (C2) an aminobenzenesulfonamide derivative represented by the following general formula (1),
When the total amount of the (A) binder polymer and the (B) photopolymerizable compound is 100 parts by weight, the content of the (D) leuco dye is 0 to 0.05 parts by weight. .

（式中、ｍは１又は２の整数である。Ｘは、水素原子、アルキル基、アルコキシ基、ハロゲン原子のいずれかであり、ｎは０〜４の整数であり、ｎが２〜４のとき複数のＸは一部又は全部が異なっていても良い。Ｒ_１及びＲ_２は、それぞれ独立して、水素原子、炭素数１〜２０のアルキル基、アルコキシ基、又はハロゲン原子、ヒドロキシル基、シアノ基及びニトロ基からなる群から選ばれる少なくとも１の置換基で置換された炭素数１〜２０のアルキル基である。）

(In the formula, m is an integer of 1 or 2. X is any one of a hydrogen atom, an alkyl group, an alkoxy group, and a halogen atom, n is an integer of 0 to 4, and n is 2 to 4. In some cases, a plurality of X may be partially or entirely different from each other, and R ₁ and R ₂ each independently represent a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an alkoxy group, a halogen atom, a hydroxyl group, (It is a C1-C20 alkyl group substituted by the at least 1 substituent chosen from the group which consists of a cyano group and a nitro group.)

  The photosensitive resin composition of the present invention preferably further contains (E) a hindered phenol-based inhibitor.

  The photoresist film of the present invention has a structure in which a support, a photosensitive resin composition layer comprising the photosensitive resin composition of the present invention, and a cover film are sequentially laminated.

The resist pattern forming method of the present invention is characterized in that the photosensitive resin composition layer of the photoresist film of the present invention is laminated on a substrate, and a resist pattern is formed through an exposure step and a development step. .
The resist pattern forming method of the present invention preferably further includes a step of performing additional exposure and / or thermosetting treatment on the resist pattern formed through the exposure step and the development step.

According to the present invention, it is possible to form a pattern with a high resolution of L / S = 10/10 (μm) or less, and a photosensitive resin composition having a small color change difference before and after exposure can be obtained. Further, by further using a hindered phenol-based inhibitor, weather resistance is improved, whitening and discoloration are suppressed even when used for a long period of time, and a photosensitive resin composition excellent in transparency and long-term reliability can be obtained. Therefore, it can be suitably used for materials used for optical electronic devices such as display devices and touch panels, for example, photo spacers for liquid crystal display elements, viewing angle expansion films for TN liquid crystals, and the like.
Since the photoresist film of the present invention has a photosensitive resin composition layer comprising the photosensitive resin composition of the present invention, it is suitable for pattern formation on a transparent substrate such as a PET film.
Since the resist pattern forming method of the present invention uses the photoresist film of the present invention, it is possible to form a resist pattern that has high resolution and little discoloration difference before and after exposure. In particular, when a photosensitive resin composition further containing a hindered phenol-based inhibitor is used, the weather resistance is improved, whitening and discoloration are suppressed even when used for a long time, and transparency and long-term reliability are achieved. An excellent resist pattern can be formed.

  Hereinafter, each embodiment of the photosensitive resin composition of the present invention, a photoresist film, and a resist pattern forming method will be sequentially described.

[Photosensitive resin composition]
The photosensitive resin composition of the present invention contains (A) a binder polymer, (B) a photopolymerizable compound, and (C) a photopolymerization initiator. Each component will be described below.

(A) Binder polymer Examples of the (A) binder polymer used in the present invention include an acrylic polymer, a polyester polymer, a polyamide polymer, an epoxy polymer, a styrene polymer, and an amide epoxy polymer. , Alkyd polymers, phenol polymers, and the like. Among these polymers, one kind can be used alone, or two or more kinds can be used in combination.

  (A) The binder polymer is preferably a carboxyl group-containing polymer. Examples of the carboxyl group-containing polymer include acrylic polymers, polyester polymers, polyamide polymers, and epoxy polymers. These carboxyl group-containing polymers are used alone or in combination of two or more. Examples of the carboxyl group-containing polymer used in combination of two or more types include, for example, two or more types of carboxyl group-containing polymers composed of different copolymerization components, two or more types of carboxyl group-containing polymers having different weight average molecular weights, and different dispersions. And two or more kinds of carboxyl group-containing polymers.

Among the carboxyl group-containing polymers, it is preferable to use an acrylic polymer obtained by copolymerizing a (meth) acrylic acid ester and an ethylenically unsaturated carboxylic acid, and if necessary, other copolymerizable monomers.
The content of the structural unit based on the (meth) acrylic acid ester (ratio of the (meth) acrylic acid ester to the total polymerizable monomer to be used) is from the viewpoint of improving the alkali developability, resolution, and release properties. It is preferably 10 to 70% by weight, particularly preferably 20 to 60% by weight, and more preferably 30 to 50% by weight.
Further, the content of the structural unit based on the ethylenically unsaturated carboxylic acid (ratio of the ethylenically unsaturated carboxylic acid to the total polymerizable monomer used) is 12 from the viewpoints of resolution, adhesion, and peelability. It is preferably -50% by weight, particularly preferably 15-40% by weight, and more preferably 18-30% by weight. If the content of the ethylenically unsaturated carboxylic acid is too small, the alkali reactivity tends to be inferior and the development time and the peeling time tend to be long. If the content is too large, the developer resistance tends to decrease and the adhesion tends to decrease.
Furthermore, the content of structural units based on other copolymerizable monomers (ratio of other copolymerizable monomers to the total polymerizable monomers used) is preferably 10 to 78% by weight, Is preferably 20 to 70% by weight, more preferably 30 to 60% by weight.
Hereinafter, the acrylic polymer will be described. However, the acrylic polymer used in the present invention is not limited to the following.

  Examples of the (meth) acrylic acid ester include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, 2-ethylhexyl monoglycidyl (meth) acrylate, 2-ethylhexyl diglycidyl (meth) acrylate, 2-ethylhexyl triglycidyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl ( Aliphatic (meth) acrylates having an alkyl group such as (meth) acrylate having 1 to 20 carbon atoms, preferably 1 to 10; phenyl (meth) acrylate, phenoxyethyl (meth) acrylate, benzyl ( ) Aromatic (meth) acrylates such as acrylate, chlorobenzyl (meth) acrylate and methoxybenzyl (meth) acrylate; amino group-containing (meth) acrylates such as diethylaminoethyl (meth) acrylate and dimethylaminoethyl (meth) acrylate; Hydroxyl group (meth) acrylates such as hydroxyethyl (meth) acrylate and hydroxypropyl (meth) acrylate; Epoxy group-containing (meth) acrylates such as glycidyl (meth) acrylate, 2,2,2-trifluoroethyl (meth) acrylate , Tetrahydrofurfuryl (meth) acrylate, and the like, and these can be used alone or in combination of two or more.

  Examples of the ethylenically unsaturated carboxylic acid include monocarboxylic acids such as acrylic acid, methacrylic acid, and crotonic acid, and dicarboxylic acids such as maleic acid, fumaric acid, and itaconic acid, and anhydrides thereof. Half esters can also be used, and these can be used alone or in combination of two or more. Of these, acrylic acid and methacrylic acid are particularly preferable.

  Examples of the other copolymerizable monomers include (meth) acrylamide, 2,2,3,3-tetrafluoropropyl (meth) acrylate, acrylamide, diacetone acrylamide, styrene, methylstyrene, dimethylstyrene, and ethylstyrene. , Isopropyl styrene, butyl styrene, hydroxy styrene, methoxy styrene, acetoxy styrene, chloro styrene, vinyl naphthalene, vinyl cyclohexane, vinyl toluene, vinyl acetate, alkyl vinyl ether, (meth) acrylonitrile, and the like. A combination of the above can be used.

For such acrylic polymers, the weight average molecular weight is preferably from 50,000 to 200,000, particularly preferably from 10,000 to 100,000, more preferably 2.5 from the viewpoints of resolution, adhesion, and peelability. It is preferably from 10,000 to 60,000, and the acid value is preferably from 100 to 300 mgKOH / g, particularly preferably from 120 to 250 mgKOH / g, and more preferably from 140 to 190 mgKOH / g.
The weight average molecular weight (Mw) is a value obtained by measuring a THF (tetrahydrofuran) solution of a dry polymer on a polystyrene basis using a GPC (gel permeation chromatography) apparatus. The acid value is the weight of KOH (potassium hydroxide) necessary to neutralize 1 g of (A) binder polymer (for example, acrylic polymer), for example, alcohols such as methanol, acetone, It is measured by neutralization titration of ketones such as methyl ethyl ketone, or a polymer dissolved in a mixed solvent thereof.

  If the weight average molecular weight is too small, the cured photosensitive resin composition tends to be brittle, and conversely if too large, the resolution and resist peelability tend to decrease. In addition, if the acid value is too small, the effect of suppressing a decrease in resolution and resist peelability tends to be weakened. On the other hand, if the acid value is too large, the effect of suppressing a decrease in fine line adhesion of the cured resist tends to be weakened. is there.

The (A) binder polymer used in the present invention has an I / O value of 0.54 to 0.74, preferably 0.54 to 0.70, and particularly preferably 0.56 to 0.68. is there. If the I / O value is too low, developability may be reduced, resulting in generation of residue on the substrate and pattern formation may be difficult. If the I / O value is too high, the resist pattern may be formed during the development process. Swelling and resolution may be reduced. In the present invention, the I / O value is a value obtained by rounding off the third decimal place.
(A) As a method of adjusting the I / O value of the binder polymer, a method of appropriately selecting at least one of the type of monomer constituting the polymer and the polymerization ratio (content) when the monomer is polymerized Is exemplified.

The I / O value is a value obtained by organically treating the polarity of various organic compounds, also called (inorganic value) / (organic value), and is a functional group contribution method in which parameters are set for each functional group. One. As the I / O value, for example, a new organic conceptual diagram (Koda Yoshio, Sato Shiro, Honma Yoshio, Sankyo Publishing (2008)); KUMAMOTO PHARMACEUTICAL BULLETIN, No. 1, No. 1-16 (1954) Chemistry, Volume 11, No. 10, 719-725 (1957); Fragrance Journal, No. 34, 97-111 (1979); Fragrance Journal, No. 50, 79-82 (1981); organic compound separation methods (Hiroo Inoue, Satoshi Uehara, Mamoru Minamigo, Nanagobo, 1990);
The concept of the I / O value is that the properties of a compound are divided into an organic group exhibiting covalent bondability and an inorganic group exhibiting ionic bondability, and all organic compounds are named as an organic axis and an inorganic axis, respectively. It is shown by positioning each point on the orthogonal coordinates.
The inorganic value is obtained by quantifying the magnitude of the influence on the boiling point of various substituents and bonds of an organic compound with reference to a hydroxyl group. Specifically, when the difference between the boiling point of linear alcohol and the boiling point of linear paraffin is about 5 ° C., the inorganic value of one hydroxyl group is defined as 100. Based on this, the value obtained by quantifying the influence of various substituents or various bonds on the boiling point is the inorganic value of the substituent that the organic compound has. For example, the inorganic value of the carboxyl group (—COOH) is 150, and the inorganic value of the double bond is 2. Therefore, the inorganic value of a certain organic compound means the sum of inorganic values such as various substituents and bonds of the compound.
The organic value is determined based on the influence of the methylene group in the molecule as a unit and the boiling point of the carbon atom representing the methylene group. That is, since the average value of the boiling point increase due to the addition of one carbon in the vicinity of 5 to 10 carbon atoms of the linear saturated hydrocarbon compound is 20 ° C., the organic value of one carbon atom is set to 20 on the basis of this. Based on this, the value obtained by quantifying the influence of various substituents and bonds on the boiling point is the organic value. For example, the organic value of a nitro group (—NO ₂ ) is 70.
The closer the I / O value is to 0, the more non-polar (hydrophobic, organic) organic compound is shown, and the higher the I / O value is, the more polar (hydrophilic, inorganic) organic compound is. It shows that.
Hereinafter, an example of a method for calculating the I / O value will be described.

  The I / O value of the methacrylic acid / methyl methacrylate / styrene copolymer (copolymer composition (molar ratio): 2/5/3) is determined by the following method. And calculated by the following formula: (inorganic value of the copolymer) / (organic value of the copolymer).

  The inorganic value of the copolymer is the inorganic value of the methacrylic acid x the molar ratio of the methacrylic acid, the inorganic value of the methyl methacrylate x the molar ratio of the methyl methacrylate, and the inorganic value of the styrene. X Calculated by calculating the sum of the styrene molar ratio.

The methacrylic acid has one carboxyl group and one double bond, the methyl methacrylate has one ester group and one double bond, and the styrene has one aromatic ring. And having one double bond,
The inorganic value of the methacrylic acid is 150 (inorganic value of carboxyl group) × 1 (number of carboxyl groups) +2 (inorganic value of double bond) × 1 (number of double bonds) = 152,
The inorganic value of the methyl methacrylate is 60 (inorganic value of ester group) × 1 (number of ester groups) +2 (inorganic value of double bonds) × 1 (number of double bonds) = 62,
The inorganic value of the styrene is 15 (inorganic value of aromatic ring) × 1 (number of aromatic rings) +2 (inorganic value of double bonds) × 1 (number of double bonds) = 17.
Therefore, the inorganic value of the copolymer is calculated by the following formula: 152 × 2 (molar ratio of methacrylic acid) + 62 × 5 (molar ratio of methyl methacrylate) + 17 × 3 (molar ratio of styrene) Is calculated to be 665.

  The organic value of the copolymer is the organic value of the methacrylic acid x the molar ratio of the methacrylic acid, the organic value of the methyl methacrylate x the molar ratio of the methyl methacrylate, and the organic value of the styrene. X Calculated by calculating the sum of the styrene molar ratio.

Since the methacrylic acid has 4 carbon atoms, the methyl methacrylate has 5 carbon atoms, and the styrene has 8 carbon atoms,
The organic value of the methacrylic acid is 20 (organic value of carbon atoms) × 4 (number of carbon atoms) = 80,
The organic value of the methyl methacrylate is 20 (organic value of carbon atoms) × 5 (number of carbon atoms) = 100,
The organic value of styrene is 20 (organic value of carbon atoms) × 8 (number of carbon atoms) = 160.
Therefore, the organic value of the copolymer has the following formula: 80 × 2 (molar ratio of the methacrylic acid) + 100 × 5 (molar ratio of the methyl methacrylate) + 160 × 3 (molar ratio of the styrene) By calculating, it is calculated to be 1140.

  Therefore, the I / O value of the copolymer is 665 (inorganic value of the copolymer) / 1140 (organic value of the copolymer) = 0.58.

(B) Photopolymerizable compound The (B) photopolymerizable compound used in the present invention is not particularly limited, and is a monomer having one polymerizable unsaturated group or a single monomer having two polymerizable unsaturated groups. A monomer and a monomer having three or more polymerizable unsaturated groups can be used, and one of these monomers can be used alone or two or more can be used in combination.

  Examples of the monomer having one polymerizable unsaturated group include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, and 2-phenoxy-2- Hydroxypropyl (meth) acrylate, 2- (meth) acryloyloxy-2-hydroxypropyl phthalate, 3-chloro-2-hydroxypropyl (meth) acrylate, glycerin mono (meth) acrylate, 2- (meth) acryloyloxyethyl acid Examples thereof include phosphate, phthalic acid derivative half (meth) acrylate, N-methylol (meth) acrylamide, and the like. These may be used alone or in combination of two or more.

Examples of the monomer having two polymerizable unsaturated groups include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, and propylene. Glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, polyethylene glycol / polypropylene glycol di (meth) acrylate, butylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, oxyethylene group-containing bisphenol A type Di (meth) acrylate, oxypropylene group-containing bisphenol A type di (meth) acrylate, oxyethylene group / oxypropylene group-containing bisphenol A type (Meth) acrylate, 1,6-hexanediol di (meth) acrylate, glycerin di (meth) acrylate, pentaerythritol di (meth) acrylate, ethylene glycol diglycidyl ether di (meth) acrylate, diethylene glycol diglycidyl ether di (meth) ) Acrylate, phthalic acid diglycidyl ester di (meth) acrylate, hydroxypivalic acid-modified neopentyl glycol di (meth) acrylate, and the like. These may be used alone or in combination of two or more.
Among these, oxyethylene group-containing bisphenol A type di (meth) acrylate and oxypropylene group-containing neopentyl glycol di (meth) acrylate are preferable from the viewpoint that the discoloration (yellowing) of the photosensitive resin after exposure is small.

  Examples of the monomer having three or more polymerizable unsaturated groups include trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, and tri (meth) acryloyloxy. Examples thereof include ethoxytrimethylolpropane, glycerin polyglycidyl ether poly (meth) acrylate and the like, and these can be used alone or in combination of two or more.

The content of the (B) photopolymerizable compound is preferably 30 to 65 parts by weight when the total amount of the (A) binder polymer is 100 parts by weight (the content of the (A) binder polymer is 35 to 70 parts by weight. 40-60 parts by weight (content of (A) binder polymer is 40-60 parts by weight), more preferably 45-55 parts by weight (content of (A) binder polymer is 45-55). Parts by weight). (B) When there is too much content of a photopolymerizable compound, the resin viscosity when forming a photoresist film will fall, and when it stores at room temperature as a film roll, the oozing from a roll edge part may generate | occur | produce. Storage stability may be reduced. (B) When there is too little content of a photopolymerizable compound, the effect of this invention may not be acquired.
In addition, when there is too much content of (A) binder polymer, it may become inadequately cured at the time of exposure, or developability may be reduced and cause residue generation on the substrate surface. (A) Binder polymer When there is too little content of this, the effect of this invention may not be acquired.

(C) Photopolymerization initiator As the (C) photopolymerization initiator used in the present invention, at least (C1) a hexaarylbisimidazole-based initiator, and (C2) an aminobenzenesulfonamide represented by the general formula (1) Contains derivatives.

  Examples of (C1) hexaarylbisimidazole derivatives include 2,2′-bis (2,3-dichlorophenyl) -4,4 ′, 5,5′-tetrakis (3-methoxyphenyl) bisimidazole, 2,2 '-Bis (2,3-dichlorophenyl) -4,4', 5,5'-tetrakis (4-methoxyphenyl) bisimidazole, 2,2'-bis (2,4-dichlorophenyl) -4,4 ', 5,5′-tetrakis (3-methoxyphenyl) phenylbisimidazole, 2,2′-bis (2,5-dichlorophenyl) -4,4 ′, 5,5′-tetrakis (3-methoxyphenyl) bisimidazole, 2,2'-bis (2,6-dichlorophenyl) -4,4 ', 5,5'-tetrakis (3-methoxyphenyl) bisimidazole, 2,2', 4,4 -Tetrakis (2-chlorophenyl) -5,5'-bis (3-methoxyphenyl) bisimidazole, 2,2'-bis (2-chlorophenyl) -4,4 ', 5,5'-tetraphenylbisimidazole, 2,2 ', 4,4'-tetrakis (2-chlorophenyl) -5,5'-bis (4-methoxyphenyl) bisimidazole, 2,2', 4,4'-tetrakis (2-chlorophenyl) -5 , 5'-bis (2,3-dimethoxyphenyl) bisimidazole, 2,2 ', 4,4'-tetrakis (2-chlorophenyl) -5,5'-bis (3,4-dimethoxyphenyl) bisimidazole, 2,2'-bis (2-chlorophenyl) -4,4 ', 5,5'-tetrakis (4-methoxyphenyl) bisimidazole, 2,2'-bis (2-chlorophene) ) -4,4 ', 5,5'-tetrakis (3,4-dimethoxyphenyl) bisimidazole, 2,2'-bis (2-chlorophenyl) -4,4', 5,5'-tetrakis (3 , 4,5-trimethoxyphenyl) bisimidazole, 2,2'-bis (2-chlorophenyl) -4,5-bis (3-methoxyphenyl) -4 ', 5'-diphenylbisimidazole, 2,2' -Bis (2-chlorophenyl) -4,5-bis (3,4-dimethoxyphenyl) -4 ', 5'-diphenylbisimidazole, 2,2'-bis (2-chlorophenyl) -4- (3,4 -Dimethoxyphenyl) -4 ', 5,5'-triphenylbisimidazole and the like can be mentioned, and these can be used alone or in combination of two or more. Among them, 2,2 ', 4,4'-tetrakis (2-chlorophenyl) -5,5'-bis (3-methoxyphenyl) bisimidazole, 2,2', 4,4'-tetrakis (2-chlorophenyl)- 5,5'-bis (2,3-dimethoxyphenyl) bisimidazole, 2,2 ', 4,4'-tetrakis (2-chlorophenyl) -5,5'-bis (3,4-dimethoxyphenyl) bisimidazole 2,2'-bis (2-chlorophenyl) -4- (3,4-dimethoxyphenyl) -4 ', 5,5'-triphenylbisimidazole, 2,2'-bis (2-chlorophenyl) -4 , 4 ′, 5,5′-tetraphenylbisimidazole is preferred in terms of ease of use, exposure sensitivity, and resolution.

(C2) In the general formula (1) representing an aminobenzenesulfonamide derivative, m is an integer of 1 or 2.
X is any one of a hydrogen atom, an alkyl group, an alkoxy group, and a halogen atom. The alkyl group is, for example, an alkyl group having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, particularly preferably 1 to 5 carbon atoms, and examples thereof include methyl, ethyl, propyl, butyl, and isobutyl. The alkoxy group is, for example, an alkoxy group having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, particularly preferably 1 to 5 carbon atoms, and examples thereof include methoxy, ethoxy, propoxy, butoxy, and isobutoxy. As for a halogen atom, a chlorine atom, a bromine atom, and an iodine atom are mentioned, for example.
n is an integer of 0 to 4, and when n is 2 to 4, a plurality of X may be partially or entirely different.
R ₁ and R ₂ are each independently a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, or an alkoxy group having 1 to 20 carbon atoms. 1-10 are preferable and, as for carbon number of an alkyl group and an alkoxy group, 1-5 are especially preferable. The alkyl group having 1 to 20 carbon atoms may be substituted with at least one substituent selected from the group consisting of a halogen atom, a hydroxyl group, a cyano group, and a nitro group.

  (C2) Specific examples of the aminobenzenesulfonamide derivative represented by the general formula (1) include 3-amino-N, N′-dimethylaminobenzenesulfonamide and 3-amino-N, N′-diethylamino. Benzenesulfonamide, 3-amino-4-ethyl-N, N′-diethylaminobenzenesulfonamide, 3-amino-4-methoxy-N, N′-diethylaminobenzenesulfonamide, 3-amino-4-methoxy-N, N′-diethoxyaminobenzenesulfonamide, 3-amino-2,4-dimethyl-N, N′-dibutylaminobenzenesulfonamide, 3-amino-4-chloro-N, N′-diethylaminobenzenesulfonamide, 4 -Amino-N, N'-diethylaminobenzenesulfonamide, 4-amino-3-ethyl-N, N'- Diethylaminobenzenesulfonamide, 2-amino-4-methoxy-N, N′-diethylcyanoaminobenzenesulfonamide, 3,5-diamino-N, N′-diethylaminobenzenesulfonamide, 3-amino-4-methoxy-N , N′-diethylnitroaminobenzenesulfonamide, 3-amino-4-methyl-N, N′-diethylaminobenzenesulfonamide, 3-amino-4-propyl-N, N′-diethoxyaminobenzenesulfonamide, 3 -Amino-4-propyl-N, N'-dimethylaminobenzenesulfonamide, 3-amino-4-propyl-N, N'-diethylaminobenzenesulfonamide, 3-amino-4-propoxy-N, N'-dimethyl Aminobenzenesulfonamide, 3-amino-4-propoxy-N, N′-di Tylaminobenzenesulfonamide, 4-amino-2-methyl-N, N′-diethylaminobenzenesulfonamide, 3,5-diamino-4-methoxy-aminobenzenesulfonamide, 3,5-diamino-N, N′- Diethylaminobenzenesulfonamide, 2-amino-4-chloro-N, N′-diethylaminobenzenesulfonamide, 3-amino-4-chloro-N, N′-diethylaminobenzenesulfonamide, 4-amino-2,6-dimethyl -N, N'-diethylaminobenzenesulfonamide, 4-amino-2,6-dimethoxy-N, N'-diethylaminobenzenesulfonamide, 3-amino-4-ethoxy-N, N'-dipropylaminobenzenesulfonamide 3-amino-2,4-dimethyl-N, N′-diethylaminobenzene Sulfonamide, 3-amino-2,4-diethoxy-N, N′-diethylaminobenzenesulfonamide, 3-amino-4-methoxy-N, N′-dibutylaminobenzenesulfonamide, 3-amino-2,4, 6, -trimethyl-N, N′-diethylaminobenzenesulfonamide, 3-amino-2,4,6, -trimethoxy-N, N′-diethylaminobenzenesulfonamide, 3-amino-4-methoxy-N, N ′ -Dipropylaminobenzenesulfonamide and the like can be mentioned, and 3-amino-4-methoxy-N, N'-diethylaminobenzenesulfonamide is preferable from the viewpoint of pattern shape and curability.

  (C) As a photopolymerization initiator, in addition to (C1) a hexaarylbisimidazole initiator and (C2) an aminobenzenesulfonamide derivative represented by the general formula (1), for example, ( C3) N-arylglycine, (C4) alkylaminobenzophenone, (C5) acridine derivative, (C6) N, N, N ′, N′-tetraarylbenzidine derivative, anthraquinone derivative such as diaminoanthraquinone, riboflavin triacetate, benzophenone , Benzyldimethyl ketal, thioxanthone derivatives, alkylaminobenzoic acid alkyl esters, triazine derivatives, coumarin derivatives such as coumarin 6, triphenylphosphine, tolylphosphine, trixylphosphine, tribiphenylphosphine, trinaphthylphosphine, Lian-tolylphosphine, tri phenanthryl phosphine triarylphosphine such may be further used, these may be used alone or in combination of two or more.

  Examples of (C3) N-aryl glycine include N-phenyl glycine, N-phenyl glycine butyl ester, Np-methylphenyl glycine ethyl ester, N-methoxyphenyl glycine, and the like. A combination of more than one species can be used. Of these, N-phenylglycine is preferred.

  Examples of (C4) alkylaminobenzophenone include 4,4′-bis (diethylamino) benzophenone, 3,3′-dimethyl-4-methoxybenzophenone, 4,4′-bis (dimethylamino) benzophenone, These can be used alone or in combination of two or more. Of these, 4,4′-bis (diethylamino) benzophenone is particularly preferred.

  Examples of (C5) acridine derivatives include 9-phenylacridine, 9- (p-methylphenyl) acridine, 9- (p-ethylphenyl) acridine, 9- (pn-propylphenyl) acridine, 9- ( p-iso-propylphenyl) acridine, 9- (pn-butylphenyl) acridine, 9- (p-tert-butylphenyl) acridine, 9- (p-methoxyphenyl) acridine, 9- (p-ethoxy) Phenyl) acridine, 9- (p-acetylphenyl) acridine, 9- (p-dimethylaminophenyl) acridine, 9- (p-cyanophenyl) acridine, 9- (p-chlorophenyl) acridine, 9- (p- Bromophenyl) acridine, 9- (m-methylphenyl) acridine, 9- (mn-propyl) Nyl) acridine, 9- (m-iso-propylphenyl) acridine, 9- (mn-butylphenyl) acridine, 9- (m-tert-butylphenyl) acridine, 9- (m-methoxyphenyl) acridine , 9- (m-ethoxyphenyl) acridine, 9- (m-acetylphenyl) acridine, 9- (m-dimethylaminophenyl) acridine, 9- (m-diethylaminophenyl) acridine, 9- (m-cyanophenyl) Acridine, 9- (m-chlorophenyl) acridine, 9- (m-bromophenyl) acridine, 9-methylacridine, 9-ethylacridine, 9-n-propylacridine, 9-iso-propylacridine, 9-cyanoethylacridine , 9-hydroxyethyl acridine, 9-chloroethyl acetate Examples include lysine, 9-methoxyacridine, 9-ethoxyacridine, 9-n-propoxyacridine, 9-iso-propoxyacridine, 1,7-bis (9-acridinyl) heptane, phenylbenzoacridine, 9-chloroethoxyacridine and the like. These can be used alone or in combination of two or more. Of these, 9-phenylacridine and 1,7-bis (9-acridinyl) heptane are preferable.

  (C6) N, N, N ′, N′-tetraarylbenzidine derivatives include, for example, N, N′-bis [4- (2-phenylethen-1-yl) -phenyl] -N, N′- Bis (2-ethyl-6-methylphenyl) -1,1′-biphenyl-4,4′-diamine, N, N′-bis [4- (2-phenylethen-1-yl) -phenyl] -N , N′-bis (4-butylphenyl) -1,1′-biphenyl-4,4′-diamine, which can be used alone or in combination of two or more.

  The content of (C) the photopolymerization initiator is preferably 0.1 to 20 parts by weight, particularly 0, relative to 100 parts by weight of the total of (A) the binder polymer and (B) the photopolymerizable compound. It is preferably 5 to 16 parts by weight, more preferably 0.8 to 12 parts by weight. (C) When there is too little content of a photoinitiator, there exists a tendency for required sensitivity not to be acquired, and when too large, it exists in the tendency which produces an insoluble matter in the photosensitive resin composition.

  In particular, for (C1) hexaarylbisimidazole-based initiator, 0.5 to 10 parts by weight is preferable with respect to 100 parts by weight in total of (A) binder polymer and (B) photopolymerizable compound, It is preferably 8 parts by weight, more preferably 2 to 6 parts by weight. (C1) The content of the hexaarylbisimidazole-based initiator is too much, may be present as an undissolved substance in the photosensitive resin composition, causing a residue, and if the content is too little, the effect of the present invention May not be obtained.

  Moreover, about (C2) aminobenzenesulfonamide derivative, 0.3-6 weight part is preferable with respect to a total of 100 weight part of (A) binder polymer and (B) photopolymerizable compound, Especially 0.5- It is preferably 5 parts by weight, more preferably 0.8 to 3 parts by weight. (C2) If the content of the aminobenzenesulfonamide derivative is too large, not only a quantitatively appropriate effect can be obtained, but also storage stability may be lowered. Moreover, when there is too little content, the effect of this invention may not be acquired.

(D) Leuco dye In the photosensitive resin composition of the present invention, the content of (D) leuco dye is 0 to 0 with respect to 100 parts by weight in total of (A) binder polymer and (B) photopolymerizable compound. 0.05 parts by weight, preferably 0 to 0.03 parts by weight, particularly preferably 0 to 0.01 parts by weight.
(D) By using a leuco dye, the exposure sensitivity is increased, but not only the resist pattern is colored blue at the time of exposure, but also the (C2) aminobenzenesulfonamide derivative represented by the general formula (1) Since the effect may be hindered, in the present invention, when the (D) leuco dye is used, it is necessary to keep the amount used in a very small amount.

  (D) As the leuco dye, for example, tris (4-dimethylamino-2-methylphenyl) methane [leucocrystal violet], tris (4-diethylaminophenyl) methane, bis (4-diethylaminophenyl)-(4-diethylamino) -2-methylphenyl) methane, bis (4-diethylamino-2-methylphenyl)-(4-diethylaminophenyl) methane, bis (1-ethyl-2-methylindol-3-yl) -phenylmethane, (4- Dimethylamino-2-methoxyphenyl) -bis (4-dimethylaminophenyl) methane, (4-dimethylamino-2-ethoxyphenyl) -bis (4-dimethylaminophenyl) methane, (4-dimethylamino-2-butoxy Phenyl) -bis (4-dimethylaminophenyl) meta , (4-dimethylamino-2-chlorophenyl) -bis (4-dimethylaminophenyl) methane, (4-dimethylamino-2-fluorophenyl) -bis (4-dimethylaminophenyl) methane, (4-diethylamino-2) -Methoxyphenyl) -bis (4-diethylaminophenyl) methane, (4-diethylamino-2-ethoxyphenyl) -bis (4-diethylaminophenyl) methane, (4-diethylamino-2-isopropoxyphenyl) -bis (4- Diethylaminophenyl) methane, (4-diethylamino-2-butoxyphenyl) -bis (4-diethylaminophenyl) methane, (4-diethylamino-2-hexoxyphenyl) -bis (4-diethylaminophenyl) methane, (4- Diethylamino-2-octyloxy Phenyl) -bis (4-diethylaminophenyl) methane, (4-diethylamino-2-dodecyloxyphenyl) -bis (4-diethylaminophenyl) methane, (4-diethylamino-2-benzyloxyphenyl) -bis (4-diethylamino) Phenyl) methane, (4-diethylamino-2-chlorophenyl) -bis (4-diethylaminophenyl) methane, (4-diethylamino-2-fluorophenyl) -bis (4-diethylaminophenyl) methane, (4-dimethylamino-2) -Methoxyphenyl) -bis (4-diethylaminophenyl) methane, (4-dimethylamino-2-ethoxyphenyl) -bis (4-diethylaminophenyl) methane, (4-diethylamino-2-methoxyphenyl) -bis (4- Dimethylaminofe Nyl) methane, (4-diethylamino-2-ethoxyphenyl) -bis (4-dimethylaminophenyl) methane, (4-piperidylino-2-ethoxyphenyl) -bis (4-dimethylaminophenyl) methane, [4- ( 1-pyrrolidinyl) -2-ethoxyphenyl] -bis (4-diethylaminophenyl) methane, (4-morpholino-2-ethoxyphenyl) -bis (4-dimethylaminophenyl) methane, (4-piperidylino-2-ethoxyphenyl) ) -Bis (4-dimethylaminophenyl) methane, [4- (1-pyrrolidinyl) -2-ethoxyphenyl] -bis (4-diethylaminophenyl) methane, (4-morpholino-2-ethoxyphenyl) -bis (4 -Diethylaminophenyl) methane, (4-N-ethyl-Np-tolylami -2-ethoxyphenyl) -bis (4-diethylaminophenyl) methane, (4-N-ethyl-N-phenylamino-2-ethoxyphenyl) -bis (4-diethylaminophenyl) methane, (4-diphenylamino-2) -Ethoxyphenyl) -bis (4-diethylaminophenyl) methane, (4-diethylamino-2-benzyloxyphenyl) -bis (4-dimethylaminophenyl) methane and the like.

(E) Hindered phenolic inhibitor The photosensitive resin composition of this invention may contain the (E) hindered phenolic inhibitor.
Examples of (E) hindered phenol inhibitors include N, N′-hexamethylenebis (3,5-di-t-butyl-4-hydroxyhydrocinnamide), 1,1,3-tris (2 -Methyl-4-hydroxy-5-t-butylphenyl) butane, 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, tetrakis [Methylene-3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate], n-octadecyl-β- (4′-hydroxy-3 ′, 5′-di-t-butyl Phenyl) propionate, 2,2'-methylenebis (4-methyl-6-tert-butylphenol), 2,2'-methylenebis (4-ethyl-6-tert-butylphenol), 4,4'-thiobis (6 t-butyl-m-cresol), 4,4′-thiobis (3-methyl-6-tert-butylphenol), N, N′-bis {3- (3,5-di-tert-butyl-4-hydroxy) Phenyl) propionyl} hydrazine, pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] and the like, and these may be used alone or in combination of two or more. Can do. Among them, N, N′-hexamethylenebis (3,5-di-t-butyl-4-hydroxyhydrocinnamide), 1,3,5-trimethyl-2,4,6-tris (3,5-di -T-butyl-4-hydroxybenzyl) benzene, 4,4'-thiobis (3-methyl-6-t-butylphenol), N, N'-bis {3- (3,5-di-t-butyl- 4-hydroxyphenyl) propionyl} hydrazine and pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] are preferably used.

  The content of the (E) hindered phenol-based inhibitor is preferably 0.01 to 2 parts by weight, and particularly preferably 0.1 to 2 parts by weight with respect to 100 parts by weight in total of the (A) binder polymer and the (B) photopolymerizable compound. It is preferably 01 to 1 part by weight, more preferably 0.02 to 0.5 part by weight. (E) When there is too much content of a hindered phenol type inhibitor, exposure sensitivity will fall, the exposure amount required in order to obtain sufficient hardening may increase very much, and it may lead to the fall of productivity. Moreover, when there is too little content, weather resistance will be inferior and the whitening phenomenon of the photosensitive resin composition may arise.

As a suitable composition of the photosensitive resin composition of this invention, the following is illustrated, for example.
When the total amount of (A) binder polymer and (B) photopolymerizable compound is 100 parts by weight,
(A) The content of the binder polymer is 35 to 70 parts by weight,
(B) The content of the photopolymerizable compound is 30 to 65 parts by weight,
(C1) The content of the hexaarylbisimidazole initiator is 0.5 to 10 parts by weight,
(C2) The content of the aminobenzenesulfonamide derivative represented by the general formula is 0.3 to 6 parts by weight,
(E) Content of hindered phenol-based inhibitor is 0.01 to 2 parts by weight

Moreover, it is preferable that the photosensitive resin composition of this invention has the following characteristic.
A color tone (L1 ^* , a1 ^* , b1 ^* ) of a transparent base material represented by L ^* a ^* b ^* color system and a photosensitive resin composition layer having a thickness of 25 μm were formed on the transparent base material. Color tone represented by L ^* a ^* b ^* color system shown by the photosensitive resin laminate after irradiating the photosensitive resin laminate with an exposure amount of 10 steps using a stove 21-step step tablet ( L2 ^* , a2 ^* , b2 ^* ) have a color difference (ΔE) of less than 3.0, preferably less than 2.0, particularly preferably less than 1.8.
The method for forming the photosensitive resin composition layer on the transparent substrate is not particularly limited. For example, the photosensitive resin composition having a thickness of 25 μm is coated with a solution containing the photosensitive resin composition and dried. Examples thereof include a method of forming a resin composition layer and a method of bonding a photoresist film having a photosensitive resin composition layer having a thickness of 25 μm on a transparent substrate to form a photosensitive resin laminate.

  Moreover, you may make the photosensitive resin composition of this invention contain a halogen compound. Examples of the halogen compound include amyl bromide, isoamyl bromide, isobutylene bromide, ethylene bromide, diphenylmethyl bromide, benzyl bromide, methylene bromide, tribromomethylphenyl sulfone, carbon tetrabromide, tris (2 , 3-dibromopropyl) phosphate, trichloroacetamide, amyl iodide, isobutyl iodide, 1,1,1-trichloro-2,2-bis (p-chlorophenyl) ethane, chlorinated triazine compounds and the like.

  Furthermore, you may make the photosensitive resin composition of this invention contain additives, such as a plasticizer, as needed. Examples of such additives include polyethylene glycol, polypropylene glycol, polyoxypropylene polyoxyethylene ether, polyoxyethylene monomethyl ether, polyoxypropylene monomethyl ether, polyoxyethylene polyoxypropylene monomethyl ether, polyoxyethylene monoethyl Ethers, polyoxypropylene monoethyl ether, glycol esters such as polyoxyethylene polyoxypropylene monoethyl ether, phthalic acid esters such as diethyl phthalate, o-toluenesulfonic acid amide, p-toluenesulfonic acid amide, citric acid Tributyl, triethyl citrate, triethyl acetyl citrate, tri-n-propyl acetyl citrate, tri-n-butyl acetyl citrate Etc. The.

  In order to improve the thermal stability and storage stability of the photosensitive resin composition of the present invention, the photosensitive resin composition can contain other radical polymerization inhibitors other than the hindered phenol-based inhibitors. . Other radical polymerization inhibitors include, for example, p-methoxyphenol, hydroquinone, pyrogallol, naphthylamine, tert-butylcatechol, cuprous chloride, 2,6-di-tert-butyl-p-cresol, nitrosophenylhydroxyamine Examples thereof include aluminum salts and diphenylnitrosamine.

  Furthermore, the photosensitive resin composition of the present invention has an adhesion imparting agent, an antioxidant, a thermal polymerization inhibitor, a surface tension modifier, a stabilizer, a chain transfer agent, an anti-oxidant, and the like within a range not losing transparency. You may contain additives, such as a foaming agent and a flame retardant, suitably. The content in the case of containing such an additive is preferably 0.01 to 20 parts by weight with respect to 100 parts by weight of the total amount of (A) the binder polymer and (B) the photopolymerizable compound. Is preferably 0.01 to 15 parts by weight, more preferably 0.01 to 10 parts by weight.

  If necessary, the photosensitive resin composition of the present invention may be methanol, ethanol, acetone, methyl ethyl ketone, methyl cellosolve, ethyl cellosolve, toluene, N, N-dimethylformamide, propylene glycol monomethyl ether, ethyl acetate, butyl acetate or the like. It may be diluted with a solvent or a mixed solvent thereof to form a solution having a solid content concentration of about 20 to 60% by weight.

[Photoresist film]
The photoresist film of the present invention has a structure in which a support, a photosensitive resin composition layer comprising the photosensitive resin composition of the present invention, and a cover film are sequentially laminated. Typically, in the photoresist film of the present invention, the photosensitive resin composition layer of the present invention is laminated on one side of the support, and the cover film is formed on the surface opposite to the support side of the photosensitive resin composition layer. Have a laminated structure. However, other layers such as an adhesive layer and a release layer may be interposed between the support and the photosensitive resin composition layer and between the photosensitive resin composition layer and the cover film. .

  The support is preferably a transparent one that transmits light emitted from the exposure light source. Examples of such a support include polyethylene terephthalate film, polyethylene naphthalate film, polyvinyl alcohol film, polyvinyl chloride film, vinyl chloride copolymer film, polyvinylidene chloride film, vinylidene chloride copolymer film, and polymethyl methacrylate. Examples thereof include a copolymer film, a polystyrene film, a polyacrylonitrile film, a styrene copolymer film, a polyamide film, and a cellulose derivative film. Among these, a polyethylene terephthalate film is preferable. These films can be stretched if necessary.

  The haze of the support is preferably 5 or less. A thinner support is advantageous in terms of image formation and economy, but a thickness of 10 to 30 μm is preferably used in order to maintain strength. Although the thickness of the photosensitive resin composition layer in a photoresist film changes with uses, Preferably it is 5-100 micrometers, Most preferably, it is 7-50 micrometers, More preferably, it is 10-40 micrometers. If the photosensitive resin composition layer is too thin, the film strength tends to be too low, and if it is too thick, the adhesion, sensitivity, and resolution tend to decrease.

  The photoresist film of this invention has a cover film on the surface on the opposite side to the support body side of the photosensitive resin composition layer. One of the important characteristics of the cover film used for the photoresist film is that it can be easily peeled off from the photosensitive resin composition layer at the time of use. The cover film is required to be smaller than the cover film. As the cover film, for example, a polyethylene film, a polypropylene film, or a polyethylene terephthalate film can be preferably used. The film thickness of the cover film is preferably 10 to 100 μm, particularly preferably 12 to 50 μm.

  The photoresist film of the present invention is produced by coating a coating liquid containing the photosensitive resin composition of the present invention on one side of a support, drying, and further coating the coated surface with a cover film. Can do. Specifically, a coating solution containing the photosensitive resin composition of the present invention is uniformly applied to one side of the support by a roll coater method, a bar coater method, or the like, and the temperature gradually increases from 50 to 120 ° C. or sequentially. It can be manufactured by drying in an oven to form a photosensitive resin composition layer and then pressure laminating a cover film on the upper surface of the layer.

[Resist pattern formation method]
Each process for forming a resist pattern on a substrate using the photoresist film of the present invention will be described.
A resist pattern using the photoresist film of the present invention can be formed by a process including a lamination process, an exposure process, and a development process. An example of a specific method is shown below.
The substrate to be processed can be appropriately selected according to the application. Examples of the substrate to be processed include PET substrates and glass substrates when transparency is required. For the purpose of producing a plate, a copper-clad laminate may be mentioned, and for the purpose of producing an uneven substrate, a silicone wafer and a ceramic substrate may be mentioned.

  First, a lamination process is performed using a laminator. After the cover film of the photoresist film is peeled and removed, the photosensitive resin composition layer is heat-pressed and laminated on the surface of the substrate to be processed with a laminator. In this case, the photosensitive resin composition layer may be laminated only on one side of the substrate surface, or may be laminated on both sides. The treatment conditions at this time are such that the pressure is generally 0.1 to 0.5 MPa and the heating temperature of the photosensitive resin composition layer is generally 40 to 130 ° C.

Next, an exposure process is performed using an exposure machine. If necessary, the support is peeled off and exposed to active light through a photomask. The exposure amount is determined by the light source illuminance and the exposure time, but may be measured using a light meter.
In the exposure process, a direct drawing exposure method may be used. The direct drawing exposure method is a method in which exposure is performed by directly drawing on a substrate without using a photomask. As the light source, for example, a semiconductor laser having a wavelength of 350 to 410 nm or an ultrahigh pressure mercury lamp is used.

  Next, development is performed after the support is peeled and removed as necessary. Since the photosensitive resin composition of the present invention is a dilute alkali development type, 0.1 to 3 wt% sodium carbonate, 0.1 to 3 wt% potassium carbonate, 0.2 to 4 wt% water is used for development. An alkaline aqueous solution such as tetramethylammonium oxide or 0.01 to 0.4% by weight potassium hydroxide is used. The pH of the alkaline aqueous solution is preferably in the range of 9 to 11, and the temperature is adjusted according to the developability of the photosensitive resin composition layer. By this development, an unexposed portion (region excluding a desired pattern image) of the photosensitive resin composition layer is removed, and a resist pattern is formed. Note that a small amount of an organic solvent or the like may be mixed in the alkaline aqueous solution in order to promote a surfactant, an antifoaming agent or development.

Although a resist pattern is obtained by the above-described steps, it is preferable to perform additional exposure such as UV curing treatment in order to improve weather resistance and chemical resistance. Exposure dose varies depending exposure sensitivity of the photosensitive resin composition layer. For example 300mJ ^/ cm ² ~5,000mJ ^/ cm 2 is preferred.
Further, the weather resistance and chemical resistance can be improved by adding a step of heat curing treatment at 80 to 200 ° C., but the resist pattern may be yellowed by the heat curing treatment.

EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated further more concretely, this invention is not limited to a following example, unless the summary is exceeded.
In the examples, “%” means a weight basis.

1) Preparation of sample for evaluation The photoresist films in Examples, Comparative Examples, and Reference Examples were prepared as follows. A solution of the photosensitive resin composition shown in Table 1 was prepared so that the solid content was 55% by weight, stirred and mixed well, and an applicator was used on a polyethylene terephthalate (PET) film having a thickness of 16 μm as a support. Thus, the coating film thickness after drying was 25 μm. It dried for 2 minutes each in 60 degreeC and 90 degreeC oven, and also it coat | covered with the 20-micrometer-thick polyethylene film from the top of the photosensitive resin composition layer, and obtained the photoresist film. The obtained photoresist film was evaluated as follows.

The symbols in Table 1 represent the following.
(A) Binder polymer A-1: Copolymer obtained by polymerizing methacrylic acid / methyl methacrylate / styrene (weight ratio 22/38/40), weight average molecular weight 41,000, solid content acid value = 163.1 mg KOH / g, I / O value = 0.57 [resin content 40%, solvent: methyl ethyl ketone / isopropyl alcohol = 3/1 (weight ratio)].
A-2: Copolymer obtained by polymerizing methacrylic acid / methyl methacrylate / styrene / benzyl methacrylate (weight ratio 28/12/20/40), weight average molecular weight 36,000, solid acid Value: 182.5 mg KOH / g, I / O value = 0.656 [resin content 42%, solvent: methyl ethyl ketone / isopropyl alcohol = 3/1 (weight ratio)].
A-3: Copolymer obtained by polymerizing methacrylic acid / methyl methacrylate / styrene / butyl acrylate (weight ratio 23/57/15/5), weight average molecular weight 60,000, solid content acid Value: 150.0 mg KOH / g, I / O value = 0.76 [resin content 40%, solvent: methyl ethyl ketone / isopropyl alcohol = 9/1 (weight ratio)].
A-4: a copolymer obtained by polymerizing methacrylic acid / methyl methacrylate / butyl acrylate / hydroxyethyl methacrylate (weight ratio 25/50/20/5), having a weight average molecular weight of 85,000, Solid content acid value = 163.1 mg KOH / g, I / O value = 0.91 [resin content 40%, solvent: methyl ethyl ketone / isopropyl alcohol = 3/1 (weight ratio)].

(B) Photopolymerizable compound B-1: An oxyethylene group-containing bisphenol A dimethacrylate having a total of 10 moles of oxyethylene groups added to both ends of bisphenol A [manufactured by Shin-Nakamura Chemical Co., Ltd., trade name: BPE-500 ]
B-2: Oxyethylene group-containing bisphenol A dimethacrylate (trade name: BPE-900, manufactured by Shin-Nakamura Chemical Co., Ltd.) in which a total of 17 moles of oxyethylene groups were added to both ends of bisphenol A

(C) Photopolymerization initiator C-1: 2,2′-bis (2-chlorophenyl) -4,4 ′, 5,5′-tetraphenylbisimidazole C-2: 3-amino-4-methoxy-N , N'-diethylbenzenesulfonamide C-3: (1-hydroxy-cyclohexyl-phenyl-ketone) [trade name: Irgacure 184]
C-4: (2-Benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1) [trade name: Irgacure 369]
C-5: (Bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide) [trade name: Irgacure 819]

(D) leuco dye D-1: leuco crystal violet

(E) A hindered phenol inhibitor E-1: 4,4′-thiobis (3-methyl-6-tert-butyl-phenol)
E-2: N, N′-bis {3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionyl} hydrazine []

2) Evaluation method After peeling and removing the polyethylene film of the photoresist film, a laminate roll temperature of 90 was applied so that the easy-adhesion surface of the PET film [U34 (thickness: 100 μm)] manufactured by Toray and the photosensitive resin composition layer surface were in contact with each other. Lamination was carried out at a roll temperature of 0.3 MPa and a laminating speed of 0.8 m / min to obtain a photosensitive resin laminate. The structure of the completed photosensitive resin laminate is PET film [U34 (thickness 100 μm)] / photosensitive resin composition layer (thickness 25 μm) / support PET film (thickness 16 μm).
After 30 minutes of lamination, a negative film (Storer 21-step tablet) made so that the amount of light transmission decreases stepwise is adhered to the support PET film (thickness 16 μm) side of the photosensitive resin laminate. The entire surface of the stove 21-step tablet was uniformly exposed by a parallel exposure machine (trade name: EXM-1201, manufactured by Oak Manufacturing Co., Ltd.) having an ultrahigh pressure mercury lamp. After exposure, the support PET film (thickness 16 μm) after 30 minutes has been peeled off, and a 0.7 wt% aqueous sodium carbonate solution at 27 ° C. is applied at a spray pressure of 0.15 MPa (complete dissolution of the unexposed portion). The unexposed portion was dissolved and removed by spray development with a development time twice as long as a cured resist image. From each exposure amount and the number of resist steps remaining after development, the exposure amount (mJ / cm ² ) at which the number of remaining step steps after development of the stove 21-step tablet becomes 5, 6, and 10 steps was examined. The results are summarized in Table 2.

In order to evaluate the appearance, the entire surface is exposed from the support PET film (thickness: 16 μm) side of the photosensitive resin laminate with an exposure amount of 10 steps after the development of the stove 21-step tablet. After exposing and allowing to stand for 30 minutes, the support PET film (thickness 16 μm) was peeled off and used as a sample for appearance evaluation.
Further, the sample for external appearance evaluation was left for 200 hours in an environment of a temperature of 85 ° C. and a humidity of 85% RH using a thermo-hygrostat (manufactured by Enomoto Kasei Co., Ltd., trade name: TH402HA). This was used as a sample for evaluation after a weather resistance test.

[Resolution]
A chrome mask having a line / space design of 6/6 to 50/50 (μm) is brought into close contact with the support PET film (thickness 16 μm) side of the photosensitive resin laminate, and the stove 21 step tablet Exposure was performed with an exposure amount of 5 steps and 6 steps after the development, and the same development processing as described above was performed. The minimum mask width (μm) at which the cured resist pattern was resolved and formed normally was defined as the resolution value. The results are summarized in Table 2.

[Adhesion]
Using a chromium mask designed so that a line / space of cured resist = 6/400 to 50/400 (μm) can be formed on the support PET film (thickness 16 μm) side of the photosensitive resin laminate, The stove 21-step tablet was exposed with an exposure amount of 5 steps and 6 steps after development, and the same development processing as described above was performed. The minimum mask width (μm) at which the cured resist pattern was normally formed was defined as the adhesion value. The results are summarized in Table 2.

[Evaluation of color difference]
Using a color difference meter (manufactured by Nippon Denshoku Industries Co., Ltd., product name: SD3000), the color tone (L1 ^* , a1 ^* , b1 ^* ) of the PET film [U34 (thickness 100 μm)] alone is measured, and this is used as reference data. It was. Thereafter, the color tone of the appearance evaluation sample ^{(L2 *, a2 *, b2} *) was measured, the color tone ^{(L1 *, a1 *, b1} *) was calculated color difference (.DELTA.E1 ^*) with. ΔE1 ^* is summarized in Table 2. Further, the color tone of the weathering test after the evaluation sample ^{(L3 *, a3 *, b3} *) was measured, the color tone ^{(L1 *, a1 *, b1} *) was calculated color difference (.DELTA.E2 ^*) with. The measurement results are summarized in Table 2.

[Visual observation after weathering test]
When the sample for evaluation after the weather resistance test is visually observed, and when no change is seen compared to the sample for appearance evaluation, a change such as “◯” (pass), discoloration, turbidity, whitening, etc. is observed Was “x” (failed) and the results are summarized in Table 2.

The photosensitive resin composition of the present invention is capable of forming a resist pattern with a high resolution of L / S = 10/10 (μm) or less, and has an effect that there is little discoloration difference before and after exposure. Further, by further using a hindered phenol-based inhibitor, weather resistance is improved, whitening and discoloration can be suppressed even when used for a long period of time, and the effects of excellent transparency and long-term reliability are also exhibited. Therefore, it can be suitably used for materials used for optical electronic devices such as display devices and touch panels, for example, photo spacers for liquid crystal display devices, viewing angle improving resists for TN liquid crystals, and the like.

Claims (7)

A photosensitive resin composition containing (A) a binder polymer, (B) a photopolymerizable compound, and (C) a photopolymerization initiator,
The (A) binder polymer has an I / O value of 0.54 to 0.74,
As the (C) photopolymerization initiator, (C1) a hexaarylbisimidazole-based initiator, and (C2) an aminobenzenesulfonamide derivative represented by the following general formula (1),
When the total amount of the (A) binder polymer and the (B) photopolymerizable compound is 100 parts by weight, the content of the (D) leuco dye is 0 to 0.05 parts by weight. Photosensitive resin composition.

(In the formula, m is an integer of 1 or 2. X is any one of a hydrogen atom, an alkyl group, an alkoxy group, and a halogen atom, n is an integer of 0 to 4, and n is 2 to 4. In some cases, a plurality of X may be partially or entirely different from each other, and R ₁ and R ₂ each independently represent a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, an alkoxy group, a halogen atom, a hydroxyl group, (It is a C1-C20 alkyl group substituted by the at least 1 substituent chosen from the group which consists of a cyano group and a nitro group.)   The photosensitive resin composition according to claim 1, further comprising (E) a hindered phenol-based inhibitor. When the total amount of the (A) binder polymer and the (B) photopolymerizable compound is 100 parts by weight,
(A) The content of the binder polymer is 35 to 70 parts by weight,
(B) The content of the photopolymerizable compound is 30 to 65 parts by weight,
(C1) The content of the hexaarylbisimidazole initiator is 0.5 to 10 parts by weight,
(C2) The content of the aminobenzenesulfonamide derivative represented by the general formula is 0.3 to 6 parts by weight,
(E) Content of hindered phenolic inhibitor is 0.01-2 weight part, The photosensitive resin composition of Claim 1 or 2 characterized by the above-mentioned. A color tone (L1 ^* , a1 ^* , b1 ^* ) of a transparent base material represented by L ^* a ^* b ^* color system and a photosensitive resin composition layer having a thickness of 25 μm were formed on the transparent base material. Color tone represented by L ^* a ^* b ^* color system shown by the photosensitive resin laminate after irradiating the photosensitive resin laminate with an exposure amount of 10 steps using a stove 21-step step tablet ( The photosensitive resin composition according to any one of claims 1 to 3, wherein a color difference (ΔE) from L2 ^* , a2 ^* , b2 ^* ) is less than 3.0.   A photoresist having a structure in which a support, a photosensitive resin composition layer comprising the photosensitive resin composition according to claim 1, and a cover film are sequentially laminated. the film.   A method for forming a resist pattern, comprising laminating the photosensitive resin composition layer of the photoresist film according to claim 5 on a substrate, and forming a resist pattern through an exposure step and a development step.   A method for forming a resist pattern, comprising a step of further performing additional exposure and / or thermosetting treatment on a resist pattern formed through an exposure step and a development step.