JPS6159334A - Photosensitive polyimide composition soluble to organic solvent - Google Patents

Abstract

PURPOSE:To obtain the titled composition having excellent heat-resisting and electrical characteristics by incorporating a bisazide compd. with a photosensi tive polyimide composed of a copolycondensation product of an aromatic tetracarboxylic acid and two sorts of the specific aromatic diamine. CONSTITUTION:(A) The aromatic tetracarboxylic acid component (e.g. 3,3',4,4'-biphenyl tetracarboxylic acid) and (B) a mixture of 50-90mol% of the aromatic diamine compd. shown by the formula I (wherein Ar1 is an aromatic resistance; R1 is an alkylene and a hydroxyalkylene group) and 50-10mol% of the aromatic diamine compd. shown by the formula II (wherein R2 is two valence organic group having an aromatic nucleus) (e.g. m-xylenediamine) are copolycondensated. The bisazide compd. shown by the formula III (wherein R3 is an organic base having two valences), e.g. 4,4'-diazide chalcone is incorporated with the photosensitive polyimide which is soluble to an organic solvent and is composed of the obtd. copolycondensate product to obtain the titled composition.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention provides a polymeric polymer containing a photosensitive group in its chain, which has excellent solubility in organic solvents and has sufficient storage stability when dissolved in an organic solvent. A novel highly sensitive aromatic polyimide composition that has excellent heat resistance, electrical and mechanical properties, and is used as a material for forming insulating films and passivation films on solid-state devices in the semiconductor industry, as well as semiconductor integrated circuits and multilayers. The present invention relates to an organic solvent-soluble photosensitive polyimide composition suitable as a glabellar insulating material for printed wiring boards and the like.

[Conventional technology]

BACKGROUND ART Materials for forming insulating films and passivation films on solid-state devices in the semiconductor industry, and insulating materials for semiconductor integrated circuits, multilayer printed wiring boards, etc., are required to have high heat resistance and insulation properties. From this point of view, various proposals have been made to form the above-mentioned passivation film etc. with polyimide, which has high insulation and heat resistance (Japanese Patent Laid-Open No. 49-115
541, JP 54-116216, JP 54-116217, JP 55-45747
No. 55-45748 and Japanese Patent Application Laid-Open No. 1983
(Refer to Publication No.-45915, etc.).

In addition, a heat-resistant photoresist composition is prepared by mixing a monomer having a photocurable group with an organic solvent-soluble polyimide (which does not have a photosensitive group) and photocuring it (Japanese Patent Laid-Open No. 54
-109828, etc.) have also been proposed.

It has also been proposed to react tetracarboxylic dianhydride with a diamine compound containing a photocrosslinkable unsaturated double bond, such as diaminochalcone, to obtain a polyimide with excellent photosensitivity and heat resistance ( Japanese Patent Publication No. 57-13122
(See Publication No. 7).

Furthermore, in recent years, attempts have been made to form relief patterns using solvent-soluble polyimides (see JP-A-58-29821 and JP-A-58-191747).

[Problem that the invention seeks to solve]

The above-mentioned Japanese Patent Application Publication No. 49-115541, Japanese Patent Application Publication No. 54-
1162] Publication No. 6, JP-A-54-116217, JP-A-55-45747, JP-A-55-451
Among the proposals described in Publication No. 48 and Japanese Unexamined Patent Publication No. 56-45915, those using polyimide are insoluble in solvents and do not have photosensitive groups; All of these polymers are modified forms of polyamic acid, which is a polyimide precursor, by amidation, esterification, etc., of the carboxyl group, and are either imidized to form polyimide during photocuring, or post-baked after photocuring. It needs to be made of polyimide.

In addition, the heat-resistant photoresist compositions proposed in JP-A-54-109828 etc. have poor photocurability;
Moreover, the heat resistance of polyimide after photocuring is also not sufficient.

Furthermore, aromatic polyimides, which have excellent heat resistance, generally have poor solubility in solvents, and therefore are not suitable for forming relief patterns, which include a step of dissolving unexposed areas in an organic solvent after photocuring.

Furthermore, although the polyimide proposed in JP-A-57-131227 has excellent photosensitivity, it has poor solubility in organic solvents, so it takes a long time to dissolve, making it difficult to form relief patterns. There is a practical problem.

Also, JP-A-58-29821 and JP-A-58-
When forming a relief pattern using the polyimide described in Japanese Patent No. 191747, a long exposure time is required.

[Means for solving problems]

In view of the above-mentioned current situation, the present inventors have conducted various studies with the aim of providing an aromatic polyimide that can easily form a relief pattern with excellent heat resistance, electrical and mechanical properties. A composition in which a specific bisazide compound is added to an aromatic polyimide consisting of a copolycondensate of tetracarboxylic acid or its dianhydride and two specific aromatic diamine compounds has excellent light transmittance and high It has been found that the above object can be achieved because it has photosensitivity, is soluble in organic solvents, and has sufficient storage stability when dissolved in organic solvents. - That is, the present invention was made based on the above findings, and consists of an aromatic tetracarboxylic acid component, 50 to 90 mol% of an aromatic cyamine compound represented by the following general formula (1), and the following - (IT
) consisting of a copolycondensate with 50 to 10 mol% of an aromatic diamine compound represented by t33! The present invention provides an organic solvent-soluble photosensitive polyimide composition in which a bisazide compound represented by the following general formula (m>) is blended with a solvent-soluble photosensitive polyimide.

(However, in the above formula, ^r1 represents an aromatic residue, and R1 represents alkylene or hydroxyalkylene.) 82 N
-R2-N 112 (II) (
However, in the above formula, R2 represents a divalent organic group containing an aromatic nucleus, )N3-R3-N3(m)(
However, in the above formula, R3 represents a divalent organic group. ) Below, the photosensitive polyimide constituting the photosensitive polyimide composition of the present invention will be described in detail along with its manufacturing method.

A typical structure of the photosensitive polyimide used in the present invention comprising the above copolycondensate is a copolycondensate of approximately equimolar amounts of an acid component and a diamine component, and in the diamine component, the general formula (1) The ratio of the aromatic diamine compound represented by and the aromatic diamine compound represented by the general formula (11) is 50 to 90 mol% of the former to 50 to 10 mol% of the latter, preferably 60 to 80 mol% of the former. The latter is 40 to 20 mol%.

If the amount of the aromatic diamine compound represented by the general formula (T1) is less than 10 mol % based on the total diamine components, the resulting polyimide will have poor storage stability when made into a polymer solution, and if the amount is less than 50 mol % %, the polyimide obtained will have a decrease in photosensitivity due to a decrease in aromatic diamine units represented by the general formula (N), which is not preferable.

The photosensitive polyimide used in the present invention is produced by the following method.

That is, the photosensitive polyimide used in the present invention contains an aromatic tetracarboxylic acid component and the general formulas (1) and (■).
The copolycondensate is synthesized by copolycondensing two aromatic diamine compounds represented by the formula to form a polyamic acid, and further dehydrating and ring-closing (imidizing) the polyamic acid.

Specifically, the aromatic tetracarphonic acid component used in the production of the photosensitive polyimide is 3.3°, 4°
, 4°-biphenyltetracarboxylic acid, or its dianhydride, 2.2', 3.3°-biphenyltetracarboxylic acid, or its dianhydride, 2,3.3'', 4'-
Biphenyltetracarboxylic acid or its dianhydride, 2
, 3.3".

Examples include 4'-hensiphenotetracarboxylic acid or its dianhydride and 3,3°,4,4''-hensiphenotetracarboxylic acid or its dianhydride, and esters of the above-mentioned aromatic tetracarboxylic acids. Although compounds, salts, etc. may be used, biphenyltetracarboxylic dianhydride is particularly preferred.

Further, as the aromatic diamine compound represented by the general formula (1), which is - of the diamine component, for example, 3.5
-diaminobenzoic acid ethyl methacrylate, 2,
4-diaminobenzoic acid ethyl methacrylate, 3
．． Examples include benzoic acid esters such as 5-diaminobenzoic acid propyl methacrylate ester and 3,5-diaminobenzoic acid glycidyl methacrylate ester.

In addition, the above general formula (1) which is another diamine component
Specifically, the aromatic diamine compound represented by is m-xylylene diamine, p-xylylene diamine, 4
．． 4°-diaminodiphenyl ether, 3.4”-diaminodiphenyl ether, p-phenylenediamine, 3
, 5-diaminobenzoic acid, 2,4-diaminotoluene,
Examples include 0-tolidine and m-diaminodiphenylsulfone.

The aromatic diamine compound represented by the general formula N) may be used in combination of two or more types as required, and the aromatic diamine compound represented by the general formula (11) used in combination with this may also be used. , it is possible to use two or more types in combination if necessary.

The photosensitive polyimide used in the present invention is polyimide 0
．． The logarithmic viscosity measured at 30°C as a solution with a concentration of 5 g/100 ml of N-methyl-2-pyrrolidone is 0.1.
-1.5, particularly preferably in the range of 0.2-1.0.

To explain in more detail the production of the photosensitive polyimide used in the present invention, the ratio of the aromatic tetracarboxylic acid component and the diamine component consisting of the two aromatic diamine compounds when synthesizing the copolycondensate is The ratio of the aromatic diamine compound represented by the general formula (1) and the aromatic diamine compound represented by the general formula (T1) is approximately equimolar, and the former is 50 to 90 mol%. The latter is 50 to 10 mol%. Preferably, these synthetic reactions are carried out in a two-step reaction in which a polymerization reaction is first carried out and then an imidization reaction is carried out at a relatively low temperature.

That is, first, the temperature is lower than 100°C, preferably 8°C in an organic solvent.
A polymerization reaction is carried out at a reaction temperature of 0°C or lower for 1 to 48 hours, and then, after diluting the polyamic acid solution obtained by this polymerization reaction with an organic solvent, acetic anhydride is carried out at a reaction temperature of 100°C or lower, preferably 80°C or lower. It is preferable to add an imidizing agent such as pyridine, tertiary amine, etc. and carry out the imidization reaction for 0.5 to 5 hours.As a result, the copolycondensate is synthesized and the polyimide used in the present invention is obtained.

Examples of organic solvents used in the polymerization reaction and the imidization reaction described above include N,N-dimethyl sulfoxide, N,
N-dimethylformamide, N,N-diethylformamide, N,N-dimethylacetamide, N,N-diethylacetamide, N-methyl-2-pyrrolidone, hexamethylenephosphoamide, etc. are used.

In the present invention, the copolycondensate is prepared by polymerizing and imidizing the aromatic tetracarboxylic acid component and the aromatic diamine compound component in an organic solvent at a high temperature of 100°C or higher in one step. It can also be synthesized by performing, but as mentioned above, by performing it in two steps,
Stable products can be obtained.

Further, the aromatic diamine compound represented by the general formula (T) used in the production of the photosensitive polyimide is a new compound, and its synthesis method is not limited, but a preferable synthesis method thereof is dinitrohen. sil alcohol and
A method of synthesizing the desired aromatic diamine compound by reacting with acrylic acid chloride or the like and then reducing the reactant can be mentioned.

Further, as the bisazide compound represented by the general formula (Iff) constituting the photosensitive polyimide composition of the present invention, 4,4゛-diazide chalcone, 4゜4゛-cyazidodihenzalacetone, 2 Examples include 6-di(4°-azidobenzal)cyclohexanone, 2,6-di(4°-7zidohenzal)-4-methylcyclohexanone, and 4,4′-diazidostilhene.

The amount of the bisazide compound blended is 0.2 to 30 parts by weight, particularly 1 to 30 parts by weight, based on 100 parts by weight of the photosensitive polyimide.
The amount is preferably 20 parts by weight. If the amount is less than 0.2 parts by weight, the sensitivity of the resulting composition will be low, and if it is more than 30 parts by weight, the properties of the film formed by the resulting composition will be deteriorated.

When the photosensitive polyimide composition of the present invention is used as a material for forming a relief pattern, it is used as a solution dissolved in an organic solvent. Examples of the organic solvent include N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, dimethylsulfoxide, hexamethylenephosphoamide, and xylene, ethyl cellosolve, and diglyme. A mixed solvent of the above-mentioned solvent and dioxane may also be used. The preferred concentration of the photosensitive polyimide solution is 3-30%.

When the photosensitive polyimide composition of the present invention is dissolved in an organic solvent, the photosensitive polyimide is usually dissolved in the organic solvent, and the bisazide compound is added to the photosensitive polyimide solution within the range of the blending amount. good.

In order to further enhance the sensitizing effect, 1-nitropyrene, 1
Acid compound sensitizers such as , 8-dinitropyrene, and cyanoacridine can be added.

Furthermore, a light-polymerizable compound having an ethylenically unsaturated group can be added to the organic solvent solution of the photosensitive polyimide composition, if necessary.

Examples of the photopolymerizable compound having an ethylenically unsaturated group include ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate,
trimethylolpropane tri(meth)acrylate,
tetramethylolmethanetetra(meth)acrylate,
N,N'-methylenebis(meth)acrylamide,
Diethylaminoethyl (meth)acrylate, 1,3.
5-triacryloylhexahydro-8-triazine,
Examples include tris(hydroxyethyl acryloyl) isocyanurate.

Furthermore, although the above organic solvent solution of the photosensitive polyimide composition is stable as it is, a thermal polymerization inhibitor can be added to further improve its stability.

Examples of the thermal polymerization inhibitor include hydroquinone,
Hydroquinone monomethyl ether, 2゜6-di-t-
Examples include butyl-p-cresol.

Moreover, an adhesion aid can be added to the organic solvent solution of the above photosensitive polyimide composition as appropriate in order to improve the adhesion to the support substrate.

Examples of the adhesive aids include γ-methacryloxypropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, and r-(2-aminoethyl)aminopropylmethyldimethoxysilane. etc. can be given.

According to the photosensitive polyimide composition of the present invention, a relief pattern can be formed in the following manner by adjusting the organic solvent solution of the photosensitive polyimide composition as described above.

That is, first, an organic solvent solution of the photosensitive polyimide composition described in item 1 is applied to a substrate, and this is dried to remove the organic solvent. Coating onto the substrate can be performed using, for example, a rotary coater. The coating film is dried at 150°C or lower, preferably at 10°C.
Perform at 0°C or below. At this time, the pressure may or may not be reduced.

After drying, a negative photomask chart is placed on the coated film, and active light such as ultraviolet rays, visible light, electron beams, and X-rays is irradiated. The unexposed areas are then washed away with a developer to obtain a polyimide relief pattern. The above developer includes N,N-dimethylformamide, N,N-
Solvents such as dimethylacetamide, dimethylsulfoxide, N-methyl-2-pyrrolidone, and hexamethylenephosphoamide, or a mixture of such solvents and methanol, ethanol, etc. can be used.

〔Example〕

Below, examples of synthesis of aromatic diamine compounds used in the production of photosensitive polyimide, production examples showing the production of photosensitive polyimide used in the present invention, examples of the present invention, and effects of the photosensitive polyimide composition of the present invention are shown. Various physical property tests and their results are listed together with comparative examples.

Synthesis Example 1 First Step 50 g of 3,5-dinitrobenzoic acid chloride was dissolved in 50 ml of THF I to a solution of 29.6 g of 2-hydroxyethyl methacrylate and pyridine 1 B, 1 gtl- dissolved in 200 ml of THF (tetrahydrofuraf). The f8 liquid obtained was added dropwise from the dropping funnel at 5 to 6°C over 1 hour. After the dropwise addition, the mixture was further stirred at 10 to 15°C for 1 hour. Thereafter, the precipitated pyridine hydrochloride was filtered out using a Buchner funnel, the filtrate was concentrated, and then poured into water to precipitate a white-yellow precipitate.

After washing the obtained precipitate several times by decantation,
It was dried in vacuo to obtain 60 g of 3,5-dinitrobenzoic acid ethyl methacrylate.

Second step A solution of 5 g of 3,5-dinitrobenzoic acid ethyl methacrylate obtained in the first step dissolved in 36 ml of acetic acid was added to a solution of 27 g of iron powder suspended in 151 parts of water/351 parts of acetic acid at a reaction temperature. The mixture was added in 2-4 ml portions while stirring to maintain the temperature at 25°C±3°C. The addition was completed in about 20 minutes, and the mixture was stirred for an additional 10 minutes.

Then, using a Buchner funnel, add ice to the filtrate from which excess iron was separated and bring it to about 0°C, and then purge with aqueous ammonia.
H was set to around 8, extracted using ethyl acetate, washed with water and dried, and ethyl acetate was removed to obtain 2.75 g of the crude target product (yield: 6
7.5%). This crude target product was purified by column chromatography. That is, 200 g of Wako gel (c-200) was packed into a 65 mmφ column and separated using a 1:1 mixed solvent of ethyl acetate and benzene as a developing solvent to obtain 1.8 g of the target product.

Melting point 88~89℃ Elemental analysis value (as C1011,6N2 o4)H
N Actual value (%) 59.36 6.0B 10.4
9 Calculated value (%) 59.08 6.10 10.6
0 Also, regarding the above target object, infrared absorption spectrum and H
- The NMR spectrum was measured and the target product was confirmed.

Synthesis Example 2 First step 40g of 3.5-dinitrohensyl alcohol was added to THF4
．． Add 40.0ml of triethylamine to the solution dissolved in 0.00ml of triethylamine.
Add 4 g and heat the solution to 3-4°C while stirring.
20g of acrylic acid chloride in T”HF200m1i
The liquid was added dropwise over 40 minutes. After the dropwise addition was completed, the mixture was stirred for an additional hour. Thereafter, this solution was filtered using a Buchner funnel, and the filtrate was removed from the THF under reduced pressure using an evaporator.
Pour the concentrate into 2.51 water to precipitate the product,
This was collected by filtration and dried to obtain 46 g of a crude dinitrated product.

The obtained crude dinitrated product was subjected to column chromatography (column 65 mmφ, Wakogel C-200 300 g,
Developing solvent benzene/ethyl acetate = 1 vol/1νo
1) to obtain 42.8 g (yield: 84%) of 3,5-dinitrohensyl acrylate as pale yellowish white crystals.

Second step 3.5-dinitrobenzyl acrylate (3,5-dinitrobenzyl acrylate obtained in the first step) 20
A solution of 140 g of iron powder dissolved in 140 g of acetic acid was added to a solution of 140 g of iron powder suspended in 70 g of acetic acid/70 g of water while stirring.
The mixture was added little by little and reacted at 0 to 25°C.

After the reaction, the filtrate was filtered to remove excess iron powder, and the filtrate was neutralized with aqueous ammonia, and 2.31% of ethyl acetate was added. Extracted with.

After drying the extract over anhydrous sodium sulfate overnight, the ethyl acetate layer was concentrated to 20-40 ml. The obtained concentrated solution was subjected to column chromatography (column 50III1φ
, 150g of silica gel Wakogel C-200, developing solvent benzene/ethyl acetate = 3vol/2vol)
10.5 g of the target product as white crystals (yield 68
．． 9%).

Elemental analysis value (as C+al112N202) HN Actual value (%) 62.24 6.46 14.58
Calculated value (%) 65.49 6.29 14.57
In addition, regarding the above target object, infrared absorption spectrum and H-
The NMR spectrum was measured and it was confirmed that it was the desired product.

Production Example I 31.3 ml of N-methyl-2-pyrrolidone (NMP), 6.067 g of 2.3.3'', 4'-biphenyltetracarboxylic dianhydride, and 3,5-diamino synthesized in Synthesis Example 1 Benzoate ethyl methacrylate 3.842
g and m-xylylenediamine 0.843 g, and 20
The reaction mixture was stirred at ℃ for 24 hours to obtain polyamic acid.

Next, 153.7 ml of NMP was added to this polyamic acid to dilute it, followed by 41.12 g of acetic anhydride and 1 ml of pyridine.
Add 5.93 g and 30.1 ml of benzene, and heat at 40°C.
The mixture was reacted for 4 hours to obtain a polyimide.

Methanol was added dropwise to this polyimide solution to precipitate polyimide, which was filtered to obtain white polyimide powder (polyimide used in the present invention).

Production Examples 2 to 5 The following Table 1 was carried out in the same manner as Production Example 1 except that the conditions for synthesis of polyamic acid and imidization of the polyamic acid in Production Example 1 were changed to the conditions shown in Table 1 below. A polyimide having the properties shown in was obtained.

Examples 1 to 5 and Comparative Example 1 2,6-C(4°-azidobenzal)-4-methylcyclohexanone (bisazide compound) was added to the polyimides obtained in Production Examples 1 to 5 in the amounts shown in Table 2 below. A photosensitive polyimide composition was obtained.

Physical property test example 1 Above! ! ! Regarding the polyimides obtained in Preparation Examples 1 to 5, the following (
The physical property tests No. 11 to (3) were conducted and the results shown in Table 2 below were obtained.

Further, the photosensitive polyimide compositions obtained in Examples 1 to 5 and Comparative Example 1 were subjected to physical property tests (4) and (5) below, and the results shown in Table 2 below were obtained.

(1) Viscosity of polyimide The logarithmic viscosity of a polyimide solution having a concentration of 0.5 g polyimide/100 ml NMP was measured at 30°C.

(2) Solubility of polyimide in NMP The solubility (t%) of polyimide in NMP was measured in the normal crystal.

(3) Thermal decomposition start temperature The weight loss start temperature was measured using a differential thermobalance TG-DSC manufactured by Rigaku Denki@.

(4) Storage Stability An NMP solution of a photosensitive polyimide composition (polyimide concentration: 10%) was stored in a sealed state at 5° C. for one week and its condition was observed.

(5) Photocuring characteristics A NMP solution (polyimide concentration 16%) of a photosensitive polyimide composition was applied to a glass plate using a spin coating machine (1000~2
00 Orpm) and dried at 50° C. for 30 minutes to form a thin film of several 11 ml thick (see Table 2 below), and this thin film was subjected to the following photosensitivity and resolution tests.

■Photosensitivity The above thin film is photocured by irradiating it with an ultra-high pressure mercury lamp (jet light 2kW) at an illuminance of 7.2mW/d (350mp>).The light irradiation time until photocuring (J/cJ)
was measured.

(2) Resolution Regarding the above thin film, a relief pattern was formed using a negative-type test chart manufactured by Toppan Printing@ (Trappan Test Chart N, 0.98±0.25μ in the minimum line) as a test chart, and the quality of the pattern was determined.

Physical property test example 2 Using the photosensitive polyimide compositions obtained in Examples 1 to 5, a thin film was created under the same conditions as the photocuring characteristics described above, and after pattern formation, heat treatment was performed at 400 ° C. for 30 minutes in a nitrogen atmosphere. No deformation of the pattern film was observed.

〔Effect of the invention〕

The photosensitive polyimide composition of the present invention has a photosensitive group (photopolymerizable group) in the polymer chain, and the acid component is aromatic tetracarboxylic acid, its dianhydride, etc., and the diamine component is the general A polyimide consisting of a copolycondensate of an aromatic diamine compound represented by the formula (r) and an aromatic diamine compound represented by the general formula (T1),
) is a photocurable composition containing a bisazide compound represented by It has sufficient storage stability for
Therefore, a relief pattern can be easily formed by photochemical means, and when forming a relief pattern, there is no need for a separate photocurable material for image formation, unlike conventional non-photosensitive polyimide. In addition, unlike photosensitive polyamic acid (polyimide precursor), it does not require an imidization process after image formation, which not only simplifies the process, but also prevents distortion and stress caused by thermal effects and shrinkage on the element. There are many excellent effects such as: Moreover, the relief pattern formed using the photosensitive polyimide composition of the present invention has excellent heat resistance, electrical and mechanical properties, and is not only effective as an insulator film or passivation film for solid-state devices in the semiconductor industry. Dena(,
It can be used as an insulating film or solder resist for multilayer wiring structures of hybrid circuits and printed circuits.

Further, the photosensitive polyimide composition of the present invention has excellent light transmittance and photocurability, and thus can form a thick film.

Claims (1)

[Scope of Claims] An aromatic tetracarboxylic acid component, 50 to 90 mol% of an aromatic diamine compound represented by the following general formula (1), and 50 to 90 mol% of an aromatic diamine compound represented by the following general formula (II) 1
An organic solvent-soluble photosensitive polyimide composition comprising a bisazide compound represented by the following general formula (III) mixed with an organic solvent-soluble photosensitive polyimide consisting of a copolycondensate with 0 mol %. ▲There are mathematical formulas, chemical formulas, tables, etc.▼(I) (However, in the above formula, Ar_1 represents an aromatic residue, and R_1
represents alkylene or hydroxyalkylene. )H_2
N-R_2-NH_2(II) (However, in the above formula, R_2 represents a divalent organic group containing an aromatic nucleus.) N_3-R_3-N_3(III) (However, in the above formula, R_3 is a divalent organic group containing an aromatic nucleus.) )