JPH08292573A - Production of photo-initiator, photosensitive composition, photosensitive material and relief pattern - Google Patents

Abstract

PURPOSE: To produce a photo-initiator having superior photosensitive characteristics and to produce a photosensitive compsn., a photosensitive material and a relief pattern using the photo-initiator. CONSTITUTION: An arom. hexaarylbisimidazole compd. represented by the formula (where each of R<1> -R<15> is H, 1-5C alkyl, halogen, trihalomethyl or 1-5C alkoxy) is combined with an arom. mercapto compd. to Produce the objective photo- initiator.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a photoinitiator, a photosensitive composition, a photosensitive material and a method for producing a relief pattern.

[0002]

2. Description of the Related Art A polyimide or its precursor, which itself has a photo-patterning property, is called a photosensitive polyimide and is used as a surface protective film of a semiconductor. For the photosensitive polyimide, several methods of imparting photosensitivity have been proposed, and typical examples thereof include those obtained by forming an ester of polyamic acid with hydroxyacrylate (Japanese Patent Publication No. 55-41422), polyamide. A compound in which an acid such as amino acrylate is mixed with an acid and a photosensitive group is introduced by a salt bond (JP-A-54-145).
No. 794) is known. Since polyamic acid itself is rigid, these materials have a disadvantage that they have low sensitivity in a film state prepared by spin coating, etc., as compared with conventional UV-curable paints and dry film resists. The photosensitive polyimide for thick film having a film thickness of 5 μm or more has a problem that good patterning property cannot be obtained.

[0003]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems of the prior art and shows a photoinitiator having excellent photosensitivity, a photosensitive composition using the same, a photosensitive material and a relief pattern. The present invention provides a manufacturing method of.

[0004]

The present invention includes (a) the following general formula (I):

[Chemical 4] (In the formula, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ and R
⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ and R ¹⁵ are each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, a halogen atom, a trihalomethyl group or an alkoxy group having 1 to 5 carbon atoms. Group) and an aromatic hexaarylbisimidazole compound (b) and an aromatic mercapto compound (b).

The present invention also provides (a) the above general formula (I).
The present invention relates to a photosensitive composition containing an aromatic hexaarylbisimidazole compound represented by, (b) an aromatic mercapto compound, and (c) an addition-polymerizable compound having a boiling point of 100 ° C. or higher at normal pressure. Also, the present invention
(A) an aromatic hexaarylbisimidazole compound represented by the general formula (I), (b) an aromatic mercapto compound, (d) a polyamic acid and (e) a carbon-carbon dimer which is dimerizable or polymerizable by actinic radiation. The present invention relates to a light-sensitive material containing a compound having a heavy bond and an amino group or a quaternized salt thereof. Further, the present invention is a method for producing a relief pattern, which comprises irradiating an actinic ray imagewise on the coating film of the photosensitive composition or the photosensitive material, developing and removing an unirradiated portion, and heating. Regarding

The photoinitiator of the present invention contains (a) an aromatic hexaarylbisimidazole compound represented by the general formula (I) and (b) an aromatic mercapto compound as essential components. In the above general formula (I), R ¹ , R ² , R ³ , R ⁴ and R
⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R
¹⁴ and R ¹⁵ are each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, a halogen atom, a trihalomethyl group or an alkoxy group having 1 to 5 carbon atoms. As a halogen atom,
Fluorine atom, chlorine atom, bromine atom, etc. are mentioned, and when the composition of the present invention is used for an interlayer insulating film, a protective film, etc. of a semiconductor, a multi-chip module, etc., it has an adverse effect on the chip (for example, contamination by becoming an ion, etc. Fluorine atom is preferable from the viewpoint of not affecting the above. Examples of the trihalomethyl group include a trifluoromethyl group, a trichloromethyl group, a tribromomethyl group, and the like, and the trifluoromethyl group is preferable for the same reason as above.

Examples of the aromatic hexaarylbisimidazole compound (a) represented by the above general formula (I) in the photoinitiator of the present invention include, for example, 2,2 ', 4,4',
5,5'-hexaallyl bisimidazole, 2,2'-
Bis (o-chlorophenyl) -4,4 ', 5,5'-tetraphenylbisimidazole, 2,2'-bis (o-
Fluorophenyl) -4,4 ', 5,5'-tetraphenylbisimidazole, 2,2'-bis (o-trifluoromethylphenyl) -4,4', 5,5'-tetraphenylbisimidazole, 2 , 2'-bis (o-chlorophenyl) -4,4 ', 5,5'-tetra- (p-methoxyphenyl) bisimidazole, 2,2'-bis (o
-Chlorophenyl) -4,4 ', 5,5'-tetra-
(M-Methoxyphenyl) bisimidazole, 2,2 '
-Bis (o-chlorophenyl) -4,4 ', 5,5'-
Examples include tetra- (3,4-dimethoxyphenyl) bisimidazole and the like. These are used alone or in combination of two or more.

Examples of the aromatic mercapto compound (b) in the photoinitiator of the present invention include those having benzene or a heterocycle as a mother nucleus and having one or two mercapto groups, and two mercapto groups. In the case of having one, one of the mercapto groups may be substituted with alkyl, aralkyl or phenyl, and may be a dimer having an alkylene group interposed or a dimer in the form of disulfide. Examples of such (b) aromatic mercapto compound include:
2-Mercaptobenzothiazole, 2-mercaptobenzoxazole, 2-mercaptobenzimidazole and the like can be mentioned as preferable ones. These are used alone or in combination of two or more.

The amount of the component (a) in the photoinitiator of the present invention is not particularly limited, and should be 5 to 95 parts by weight based on 100 parts by weight of the total amount of the components (a) and (b). Is preferred. If the amount is less than 5 parts by weight, the sensitivity tends to be poor, and if it exceeds 95 parts by weight, the compound tends to be insoluble in the developing solution. In addition, the amount of the component (b) in the photoinitiator of the present invention is not particularly limited, and (a)
5 to 100 parts by weight of the total amount of the component and the component (b)
It is preferably 95 parts by weight. If the amount is less than 5 parts by weight, the unexposed portion tends to be insoluble in the developing solution, and if it exceeds 95 parts by weight, the sensitivity tends to be poor.

The photosensitive composition of the present invention contains the photoinitiator of the present invention and (c) an addition-polymerizable compound having a boiling point of 100 ° C. or higher at atmospheric pressure as essential components.

The (c) addition-polymerizable compound in the photosensitive composition of the present invention must have a boiling point of 100 ° C. or higher at normal pressure. Boiling point is 10 at normal pressure
If it is less than 0 ° C., the addition-polymerizable compound will be volatilized when the solvent contained in the system is removed by drying or the like or when it is irradiated with an actinic ray.

In the photosensitive composition of the present invention, (c) the addition-polymerizable compound having a boiling point of 100 ° C. or higher at normal pressure is, for example, polycondensed alcohol with α, β-unsaturated carboxylic acid. And the like. Examples of such a compound include ethylene glycol di (meth) acrylate (meaning diacrylate or dimethacrylate, the same applies hereinafter), triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, trimethylolpropane. Di (meth) acrylate, trimethylolpropane tri (meth) acrylate, 1,2-propylene glycol di (meth) acrylate, di (1,2-propylene glycol) di (meth) acrylate, tri (1,2-propylene glycol) ) Di (meth) acrylate, tetra (1,2-propylene glycol) di (meth) acrylate, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylate Relate, diethylaminopropyl (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, styrene , Divinylbenzene, 4-
Vinyltoluene, 4-vinylpyridine, N-vinylpyrrolidone, 2-hydroxyethyl (meth) acrylate,
Examples thereof include 1,3- (meth) acryloyloxy-2-hydroxypropane, methylenebisacrylamide, N, N-dimethylacrylamide and N-methylolacrylamide, which may be used alone or in combination of two or more.

Further, (c) the addition-polymerizable compound having a boiling point of 100 ° C. or higher at normal pressure is soluble in a commonly used organic solvent in order to form a uniform composition with the photoinitiator and the like. It is preferable. Examples of the organic solvent include acetone, methyl ethyl ketone, toluene, chloroform, methanol, ethanol, 1-propanol,
2-propanol, 1-butanol, 2-butanol,
t-butanol, ethylene glycol monomethyl ether, xylene, tetrahydrofuran, dioxane, N,
Examples thereof include N-dimethylacetamide, N, N-dimethylformamide, N-methyl-2-pyrrolidone, γ-butyrolactone, dimethylsulfoxide, ethylene carbonate, propylene carbonate, sulfolane, and the like, which may be used alone or in combination of two or more kinds. used.

The blending amount of the photoinitiator of the present invention in the photosensitive composition of the present invention is not particularly limited, and is based on 100 parts by weight of the total amount of the photoinitiator of the present invention and the component (c).
It is preferably 1 to 15 parts by weight. This blend amount is
If it is less than 1 part by weight, the sensitivity tends to be poor, and if it exceeds 15 parts by weight, the sensitivity tends to be poor and the developability tends to be poor. In addition, the compounding amount of the component (c) in the photosensitive composition of the present invention is not particularly limited, and is 85 to 9 with respect to 100 parts by weight of the total amount of the photoinitiator of the present invention and the component (c).
It is preferably 9 parts by weight. If the amount is less than 85 parts by weight, the sensitivity tends to be poor and the developability tends to be poor. If it exceeds 99 parts by weight, the sensitivity tends to be poor.

In the photosensitive composition of the present invention, the components (a) and (b) of the photoinitiator of the present invention may be compounded in the following order after the components (a) and (b) are mixed in advance. , (C) component, and can be blended,
The component (a) may be added to the component (c), and then the component (b) may be separately added and mixed, or the component (b) may be added to the component (c) and then the component (a) may be separately added. Can also be added and blended.

The photosensitive composition of the present invention may contain other photoinitiator, if necessary. Other photoinitiators include, for example, Michler's ketone, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, 2-t-butylanthraquinone, 2-ethylanthraquinone, 4,4'-bis (diethylamino) benzophenone, acetophenone, benzophenone. , Thioxanthone, 2,2-dimethoxy-2-
Phenylacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl- [4- (methylthio)
Phenyl] -2-morpholino-1-propanone, benzyl, diphenyl disulfide, phenanthrenequinone, 2-isopropylthioxanthone, riboflavin tetrabutyrate, N-phenyldiethanolamine, 2
-(O-Ethoxycarbonyl) oxyimino-1,3-
Diphenylpropanedione, 1-phenyl-2- (o-
(Ethoxycarbonyl) oxyiminopropan-1-one, 3,3 ′, 4,4′-tetra (t-butylperoxycarbonyl) benzophenone, N- (p-cyanophenyl) glycine, N- (p-methylsulfonylphenyl) ) Glycine and the like can be mentioned, and these can be used alone or in combination of two or more kinds.

The amount of the other photoinitiator compounded is not particularly limited, and the total amount of the photoinitiator of the present invention and the component (c) is 100
It is preferably 1 to 10 parts by weight with respect to parts by weight.

The photosensitive composition of the present invention may contain a high molecular weight organic polymer, if necessary, in order to improve properties such as adhesion to a substrate, chemical resistance and film property. You can As the high molecular weight organic polymer, for example,
(B) Manufactured from copolyester (polyhydric alcohol (diethylene glycol, triethylene glycol, tetraethylene glycol, trimethylolpropane, neopentyl glycol, etc.)) and polyhydric carboxylic acid (terephthalic acid, isophthalic acid, sebacic acid, adipic acid, etc.) Copolyester), (b) vinyl polymer (methacrylic acid, acrylic acid, methacrylic acid or alkyl ester of acrylic acid (methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-hydroxyethyl (meth)) A homopolymer or copolymer of vinyl monomers such as acrylate, phenyl (meth) acrylate, benzyl (meth) acrylate, 2-dimethylaminoethyl (meth) acrylate, and 2-ethylhexyl (meth) acrylate) , (C) poly formaldehyde,
(D) Polyurethane, (e) Polycarbonate (f) Polyamic acid (to) Cellulose ester (methyl cellulose, ethyl cellulose, etc.) and the like can be mentioned, and these can be used alone or in combination of two or more kinds.

The weight average molecular weight (for example, measured by GPC and converted into polystyrene) of the high molecular weight organic polymer is
It is preferably 10,000 to 700,000.
When the weight average molecular weight is less than 10,000, the strength and heat resistance of the film tend to decrease, and when it exceeds 700,000, the developability and workability tend to decrease.

The blending amount of the high molecular weight organic polymer is preferably 20 to 80% by weight based on the total amount of the photosensitive composition of the present invention. If the blending amount is less than 20% by weight,
Developability, coating property, etc. tend to be poor, and if it exceeds 80% by weight, sensitivity, heat resistance, etc. tend to be poor.

Further, the photosensitive composition of the present invention may contain coloring substances such as dyes and pigments, if necessary. Examples of the coloring substance include fuchsin, crystal violet, methyl orange, Nile blue 2B, Victoria pure blue, malachite green, night green B, and spirone blue. These are used alone or in combination of two or more. It

Further, the photosensitive composition of the present invention may contain a sensitizing dye, if necessary. Examples of the sensitizing dye include 7-diethylaminocoumarin, 3,
3'-carbonylbis (7-diethylamino) coumarin, 3,3'-carbonylbis (7-dimethoxy) coumarin, 3-thienylcarbonyl-7-diethylaminocoumarin, 3-benzoylcoumarin, 3-benzoyl-7
-Methoxycoumarin, 3- (4'-methoxybenzoyl) coumarin, 3,3'-carbonylbis-5,7-
(Dimethoxy) coumarin, benzalacetophenone,
4'-dimethylaminobenzalacetophenone, 4'-
Examples thereof include acetaminobenzal-4-methoxyacetophenone, and these are used alone or in combination of two or more kinds.

The photosensitive composition of the present invention is known to be used in a photosensitive resin composition such as an organic solvent (as described above), a plasticizer, an adhesion promoter, a polymerization inhibitor, etc., if necessary. Other additives can be included.

The light-sensitive material of the present invention comprises the photoinitiator of the present invention, (d) a polyamic acid, and (e) a carbon-carbon double bond dimerizable or polymerizable by actinic radiation and an amino group or a quaternized salt thereof. A compound having and is an essential component.

The polyamic acid (d) in the light-sensitive material of the present invention can be obtained, for example, by addition polymerization using a tetracarboxylic dianhydride and a diamine compound as materials.

Examples of the tetracarboxylic dianhydride include pyromellitic dianhydride, 3,3 ', 4,4'-benzophenone tetracarboxylic dianhydride, 3,3',
4,4'-biphenyltetracarboxylic dianhydride, 1,
2,5,6-naphthalenetetracarboxylic dianhydride,
2,3,6,7-naphthalenetetracarboxylic dianhydride, 2,3,5,6-pyridinetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 3, 4,9,10-Perylenetetracarboxylic acid dianhydride, 4,4'-sulfonyldiphthalic acid dianhydride, m
-Terphenyl-3,3 ", 4,4" -tetracarboxylic dianhydride, p-terphenyl-3,3 ", 4,4"-
Tetracarboxylic acid dianhydride, 4,4'-oxydiphthalic acid dianhydride, 1,1,1,3,3,3-hexafluoro-2,2-bis (2,3-dicarboxyphenyl) propane dianhydride Substance, 2,2-bis (2,3-dicarboxyphenyl) propane dianhydride, 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, 1,1,1,
3,3,3-Hexafluoro-2,2'-bis [4-
(2,3-Dicarboxyphenoxy) phenyl] propane dianhydride, 1,1,1,3,3,3-hexafluoro-2,2'-bis [4- (3,4-dicarboxyphenoxy) phenyl ] Propane dianhydride and the like can be mentioned, and these can be used alone or in combination of two or more kinds.

As the diamine compound, for example, aromatic diamine [p-phenylenediamine, m-phenylenediamine, p-xylylenediamine, m-xylylenediamine, 1,5-diaminonaphthalene, benzidine, 3,
3'-dimethylbenzidine, 3,3'-dimethoxybenzidine, 4,4 '(or 3,4'-, 3,3'-, 2,
4 '-)-diaminodiphenylmethane, 4,4' (or 3,4'-, 3,3'-, 2,4 '-)-diaminodiphenyl ether, 4,4' (or 3,4'-, 3, 3 '
-, 2,4 '-)-diaminodiphenyl sulfone,
4,4 '(or 3,4'-, 3,3'-, 2,4'-)
-Diaminodiphenyl sulfide, 4,4'-benzophenone diamine, 3,3'-benzophenone diamine,
4,4'-di (4-aminophenoxy) phenyl sulfone, 4,4'-bis (4-aminophenoxy) biphenyl, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4- Aminophenoxy) benzene,
1,1,1,3,3,3-hexafluoro-2,2-bis (4-aminophenyl) propane, 2,2-bis [4
-(4-aminophenoxy) phenyl] propane, 3,
3-dimethyl-4,4'-diaminodiphenylmethane,
3,3 ', 5,5'-Tetramethyl-4,4'-diaminodiphenylmethane, 4,4'-di (3-aminophenoxy) phenyl sulfone, 3,3'-diaminodiphenyl sulfone, 2,2'- Bis (4-aminophenyl) propane, etc.], heterocyclic diamine [2,6-diaminopyridine, 2,4-diaminopyrimidine, 2,4-diamino-s-triazine, 2,7-diaminobenzofuran,
2,7-diaminocarbazole, 3,7-diaminophenothiazine, 2,5-diamino-1,3,4-thiadiazole, 2,4-diamino-6-phenyl-s-triazine, etc.], aliphatic diamine [trimethylene Diamine, tetramethylenediamine, hexamethylenediamine, 2,
2-dimethylpropylenediamine, diaminopolysiloxane shown below, etc., and these are used alone or in combination of two or more kinds.

Embedded image (In the formula, m and n are each independently an integer of 1 to 10)

Examples of the compound (e) having a carbon-carbon double bond dimerizable or polymerizable by actinic radiation and an amino group or a quaternized salt thereof in the light-sensitive material of the present invention include:

[Chemical 6] And the like, and these are used alone or in combination of two or more kinds.

In the light-sensitive material of the present invention, (d) 1 mol of a carboxyl group of a polyamic acid, (e) a carbon-carbon double bond dimerizable or polymerizable by actinic radiation and an amino group or a quaternary thereof. It is preferable to use it in an amount of 1 mol of the compound having a cation salt.

The compounding amount of the photoinitiator of the present invention in the light-sensitive material of the present invention is not particularly limited, and is preferably 1 to 300 parts by weight with respect to 100 parts by weight of (d) polyamic acid. It is more preferable that the amount is ˜20 parts by weight. If the amount is less than 1 part by weight, the photoreactivity tends to be low and the sensitivity tends to be poor, and if it exceeds 300 parts by weight,
Storage stability tends to be poor.

In the light-sensitive material of the present invention, the component (a)
The components (b), (d) and (e) may be mixed in any order by adding the other components (a), (b) and (e) to the component (d). Well, again
In addition to the component (e), other components (a), (b) and (d)
The components may be combined in any order.

The light-sensitive material of the present invention preferably contains (f) a bisazide compound. Examples of the (f) bisazide compound include:

[Chemical 7]

Embedded image Etc.

The blending amount of the component (f) is not particularly limited, and is 0.01 to 100 parts by weight of the polyamic acid.
It is preferably 10 parts by weight. This blending amount is 0.
If it is less than 01 parts by weight, the sensitivity tends to be poor, and if it exceeds 10 parts by weight, the storage stability tends to be poor.

The photosensitive material of the present invention may contain, if necessary, other photoinitiators which can be used in the photosensitive composition of the present invention.

The relief pattern in the present invention is obtained by irradiating actinic rays or actinic rays imagewise on a coating film obtained by using the photosensitive composition of the present invention or the photosensitive material of the present invention,
It can be manufactured by developing and removing the unirradiated portion.

The coating film is applied onto a substrate such as a silicon wafer, a metal substrate, a glass substrate or a ceramic substrate by a method such as a dipping method, a spray method, a screen printing method or a spin coating method, and most of the solvent is applied. Obtained by heating and drying. Examples of the actinic rays or actinic rays to be applied include
Examples thereof include ultraviolet rays, far ultraviolet rays, visible light, electron beams, and X-rays. As a developer for developing and removing the unirradiated portion, N, N-
A good solvent such as dimethylformamide, N, N-dimethylacetamide or N-methyl-2-pyrrolidone, or a mixed solvent thereof with a poor solvent such as lower alcohol, water or aromatic hydrocarbon can be used. Also, after development, if necessary,
Rinsing with a poor solvent or the like and drying at around 100 ° C. can stabilize the pattern.

[0037]

The present invention will be described below with reference to examples. Examples 1 to 6 and Comparative Examples 1 to 3, 4,4′-diaminodiphenyl ether and pyromellitic dianhydride were reacted in an equimolar amount by an ordinary method to obtain N-methyl-2-pyrrolidone of polyamic acid. Solution 1
After blending 0 g (solid content 20% by weight), dimethylaminoethyl methacrylate 1.8 g, the aromatic bisimidazole compound shown in Table 1, the aromatic mercapto compound shown in Table 1 and the bisazide compound shown in Table 1, The mixture was stirred and mixed to obtain a light-sensitive material.

The obtained light-sensitive material was filtered with a filter, spin-coated on a silicon wafer, and then heated on a hot plate at 100 ° C. for 200 seconds to dry the solvent, thereby forming a film having a thickness of 20 μm. A photosensitive coating film was obtained. Pattern exposure was performed on the obtained photosensitive coating film through a photomask by a mirror projection exposure device using an ultra-high pressure mercury lamp as a light source. The exposure dose at this time was 100 mJ / cm ² .

After exposure, immersion development was carried out with a mixed solution of N-methyl-2-pyrrolidone and methyl alcohol (volume ratio 4/1), and further rinsed with ethanol. The pattern shape after development was observed with a magnifying glass, and the results are shown in Table 1.
Also, the obtained residual film rate (value obtained by dividing the film thickness by the initial film thickness)
The minimum opening through hole diameter (opening diameter) is also shown in Table 1. The larger the residual film rate, the better the characteristics such as effect, and the smaller the minimum opening through-hole diameter, the better the characteristics such as the resolution.

[0040]

[Table 1]

From the results shown in Table 1, the photosensitive compositions of the present invention shown in Examples are compared with the photosensitive compositions of Comparative Examples.
It has excellent photosensitivity.

Example 7 The developed pattern obtained in Example 4 was subjected to a nitrogen atmosphere at 100 ° C. for 15 minutes, 200 ° C. for 20 minutes, and 350 ° C.
After heating for 60 minutes, a good polyimide relief pattern having a film thickness of 10 μm was obtained.

[0043]

The photoinitiator according to claim 1 exhibits photosensitivity based on excellent photoinitiating ability, and is suitable for a photosensitive composition and a photosensitive material. The photosensitive composition according to claim 2 exhibits excellent photosensitive characteristics. With the light-sensitive material according to the third aspect, a relief pattern having excellent characteristics such as heat resistance and shape can be obtained. The light-sensitive material according to the fourth aspect has the effects of the light-sensitive material according to the third aspect, and can obtain a relief pattern having higher sensitivity and excellent mechanical characteristics. The method for producing a relief pattern according to claim 5 can produce a relief pattern having excellent characteristics such as heat resistance and shape.

Claims (5)

[Claims] 1. (a) The following general formula (I): (In the formula, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ and R
⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ and R ¹⁵ are each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, a halogen atom, a trihalomethyl group or an alkoxy group having 1 to 5 carbon atoms. A photoinitiator comprising a combination of an aromatic hexaarylbisimidazole compound represented by the formula (1) and an aromatic mercapto compound (b). 2. (a) The following general formula (I): (In the formula, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ and R
⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ and R ¹⁵ are each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, a halogen atom, a trihalomethyl group or an alkoxy group having 1 to 5 carbon atoms. Group), an aromatic hexaarylbisimidazole compound, (b) an aromatic mercapto compound, and (c)
A photosensitive composition containing an addition-polymerizable compound having a boiling point of 100 ° C. or higher at normal pressure. (A) The following general formula (I): (In the formula, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ and R
⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ and R ¹⁵ are each independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, a halogen atom, a trihalomethyl group or an alkoxy group having 1 to 5 carbon atoms. Group)), an aromatic hexaarylbisimidazole compound, (b) an aromatic mercapto compound, (d) a polyamic acid, and (e) a carbon-carbon double bond dimerizable or polymerizable by actinic radiation and an amino group. Alternatively, a light-sensitive material containing a compound having a quaternized salt thereof. 4. The photosensitive material according to claim 3, further comprising (f) a bisazide compound. 5. Irradiating imagewise with actinic rays from the coating of the photosensitive composition according to claim 2 or the photosensitive material according to claim 3 or 4, developing-removing the unirradiated portion, and heating. A method for producing a relief pattern characterized by: