JPH09188745A - Photosensitive film material for insulating circuit substrate, flexible printed wiring board and successive multilayered substrate using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a photosensitive film material suitable for a cover lay of a flexible printed wiring board, an insulating material, etc., for a successive multilayered substrate and the flexible printed wiring board or successive multilayered substrate using the photosensitive film material. SOLUTION: This photosensitive film material is formed of a composition consisting essentially of an oligomer, represented by the formula [X denotes a bivalent group or the absence; (n) denotes a number of 1-10; R1 to R8 denote each hydrogen atom, an alkyl group or a halogen atom which may respectively be same or different; R9 denotes hydrogen atom or methyl group] and obtained by reacting an epoxy acrylate with an acid anhydride and a compound having epoxy group at a weight ratio of the oligomer to the compound having the epoxy group within the range of 0.1-10. Furthermore, the flexible printed wiring board and successive multilayered substrate use the photosensitive film material. Since the photosensitive film material is capable of carrying out the patterning in an alkaline aqueous solution with a good accuracy, excellent in filling properties in a circuit, heat resistance and mechanical characteristics, the photosensitive film material is extremely useful as industrial materials such as a cover lay of the flexible printed wiring board, an insulating material, etc., for the successive multilayered substrate.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photosensitive film material suitable for a coverlay of a flexible printed wiring board or an insulating material of a sequential multilayer substrate, and a flexible print using the photosensitive film material as a coverlay material or an interlayer insulating material. The present invention relates to a wiring board or a sequential multilayer board and a method for manufacturing these.

[0002]

2. Description of the Related Art In recent years, electronic devices and computers have been required to be smaller and more sophisticated than before, and accordingly, components used at higher densities have been required. ing. For example, even in a printed wiring board, in order to improve the wiring density per unit volume,
The miniaturization and multi-layering of circuits have been promoted, and the materials used have been designed to match them. In particular, in recent years, many resist materials having photosensitivity have been proposed. Among them, it can be said that the photosensitive etching resist used for forming a conductor circuit supports a circuit miniaturization technique. Absent.

However, most of the photosensitive resins that have been proposed so far have problems in heat resistance and mechanical properties, and their applications are greatly limited, such as etching resists that are finally removed. It has the drawback of Also, except for the so-called dry film etching resist, most of it is supplied in the form of a resin solution in which a photosensitive resin is dissolved in an organic solvent.
There is a problem that a very special device is required to industrially apply such a resin solution onto a sheet-shaped printed wiring board or the like. Furthermore, in many cases, the developing solution used in the developing step, which is the patterning step of the photosensitive resin, is an organic solvent, and there are problems in the working environment and waste liquid treatment.

For example, Japanese Unexamined Patent Publication No. 6-268380 discloses a printed wiring board using a photosensitive resin, and the photosensitive resin used therein is used in the form of a resin solution. Therefore, a special device is required for coating, and the developing solution used for developing is an organic type, which causes a problem in the working environment.

In order to solve these problems, JP-A-6-
No. 148877 or the like discloses a film-formable rubber,
A photosensitive element comprising a phenolic resin, an epoxy resin, a photo-curing agent for the epoxy resin, etc. is disclosed.
However, when such a composition is used, it is said that the heat resistance of the finally obtained film is insufficient, the application to which it is applied is significantly limited, and the precision in patterning is sufficient. hard.

Further, JP-A-5-339356 and the like disclose a photosensitive resin composition in which a photopolymerizable unsaturated compound having a carboxyl group based on an epoxy acrylate compound is used together with an epoxy compound.
However, it is premised that the photosensitive resin composition is directly coated on a color liquid crystal display or a printed wiring board in a solution state by using a roll coater machine, a spinner machine or the like, and in that case, as described above. Problems with various facilities occur.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a photosensitive film material suitable for a cover lay of a flexible printed wiring board or an insulating material of a sequentially multilayered substrate and capable of forming a pattern with an alkaline aqueous solution. is there.
Another object of the present invention is to provide a flexible printed wiring board or a sequential multilayer board using a photosensitive film material capable of forming a pattern with an alkaline aqueous solution as a cover lay material or an interlayer insulating material, and a manufacturing method thereof. Especially.

[0008]

That is, the present invention contains, as an essential component, an oligomer obtained by reacting an epoxy acrylate compound represented by the following general formula (1) with an acid anhydride and a compound having an epoxy group. And the weight ratio of the oligomer to the compound having an epoxy group is 0.1 to
A photosensitive film material for insulating a circuit board, which is formed from a composition within the range of 10. The present invention also provides a flexible printed wiring board or a sequential multi-layered board using the photosensitive film material for insulating a circuit board as a cover lay material or an interlayer insulating material, and a method for manufacturing these.

[0009]

Embedded image

(In the formula, X represents a divalent group or absent,
n represents the number of 1-10. R _{1 to} R ₈ each represent a hydrogen atom, an alkyl group or a halogen atom, which may be the same or different, and R ₉ represents a hydrogen atom or a methyl group. )

Examples of X in the formula (1) include a divalent group such as a methylene group, a 2-propylidene group, a 2- (hexafluoro) propylidene group, a carbonyl group, an ether group and a sulfone group, or a direct bond. However, it is preferably a 2-propylidene group or a direct bond. Also,
R _{1 to} R ₈ are each a hydrogen atom, for example, an alkyl group such as a methyl group, an ethyl group, a propyl group or an isopropyl group,
Examples include halogen atoms such as chlorine and bromine,
Preferred is hydrogen or bromine. n represents the average number of repetitions and is a number of 1 to 10, but preferably 1 to 2
It is.

In particular, when a bisphenol A type epoxy acrylate compound in which X is a 2-propylidene group is used as a part or all of the epoxy acrylate compound, the photosensitive film material of the present invention can be subjected to patterning and subsequent heat curing. By applying the treatment, the heat resistance and mechanical properties of the finally obtained film can be improved.

Examples of the acid anhydride used for producing the oligomer of the present invention include dicarboxylic acid anhydrides such as phthalic anhydride, tetrahydrophthalic anhydride and hexahydrophthalic anhydride, and pyromellitic dianhydride. ,
Biphenyl tetracarboxylic dianhydride, benzophenone tetracarboxylic dianhydride, diphenyl sulfone tetracarboxylic dianhydride, diphenyl ether tetracarboxylic dianhydride, tetracarboxylic dianhydride such as ethylene glycol bis trimellitate dianhydride, Further examples include trimellitic anhydride. Further, these acid anhydrides may be used alone, or two or more kinds of acid anhydrides may be used in combination.
And, it is preferable to use ethylene glycol bistrimellitate dianhydride as the acid anhydride in whole or in part, whereby the mechanical properties such as flexibility of the finally obtained film are improved.

The above-mentioned epoxy acrylate compound and the above-mentioned acid anhydride can be reacted to produce an oligomer which is one of the essential components of the present invention. The weight average molecular weight of the oligomer of the present invention is 500 to 1,000,0.
00, preferably 700 to 500,000, and more preferably 1,000 to 100,000. If the weight average molecular weight is less than 500, the mechanical properties of the finally obtained film will be deteriorated, resulting in 1,000,000.
If it is larger, it becomes difficult to form a pattern with an alkaline aqueous solution.

The photosensitive film material of the present invention contains an epoxy group-containing compound as an essential component in addition to the above oligomer. Examples of the compound having an epoxy group include compounds having an epoxy group such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolac type epoxy resin, orthocresol novolac type epoxy resin and bromides thereof. Any one can be used if it exists. And
Flame retardancy can be imparted to the photosensitive film material of the present invention by using a compound having a brominated epoxy group in a part or all of the compound having an epoxy group.

The weight ratio of the oligomer to the compound having an epoxy group in the present invention, that is, the ratio of the oligomer / the compound having an epoxy group is 0.1 to 10, preferably 0.2 to 5. . This ratio is 0.
When it is less than 1, it is difficult to perform patterning with an alkaline aqueous solution, and when it exceeds 10, heat resistance and chemical resistance are deteriorated.

Next, the photosensitive film material of the present invention can be completed by forming a composition containing the above-mentioned oligomer and epoxy as essential components into a film.
The film shape here means not only a single film,
It also means a film-like film formed on a supporting base material such as a polymer film or metal foil that is finally removed by an operation such as peeling, but a film or coating film permanently formed on the base material. Is not included. Further, the photosensitive film material of the present invention formed on a supporting base material can be protected with a polymer film or the like in order to prevent foreign matter from adhering and scratches.

In order to impart various characteristics to the photosensitive film material of the present invention, other components such as amines, photopolymerization initiators, photosensitizers, monomers such as polyfunctional acrylates, plating catalysts, etc. It is also possible to add a co-oxide of indium and tin or a filler such as silica in advance. Further, in order to improve the fluidity of the photosensitive film before pattern formation, it is possible to contain a solvent.

The method for forming the above composition into a film may be a known method. For example, the composition is dissolved or dispersed in a solvent, die coater, knife coater,
After coating on the supporting substrate using an arbitrary coating device such as a reverse roll coater, the solvent can be evaporated to form a film. As the supporting substrate, a polymer film such as polyethylene terephthalate or a metal foil can be used. Further, it is also possible to use two or more kinds of compositions having different constitutions as required to form a multilayer photosensitive film material having two or more layers.

The thus-obtained photosensitive film material of the present invention can be patterned with extremely high accuracy in an alkaline aqueous solution, and also has heat resistance and mechanical properties. It can be used for various purposes.

A preferred application of the photosensitive film material of the present invention is a coverlay for a flexible printed wiring board. In other words, the photosensitive film material of the present invention can form an insulating layer called a coverlay on the flexible printed wiring board for the purpose of protecting the circuit by a simple operation of laminating, as well as accurate patterning and soldering. This is because it has sufficient heat resistance for processes such as gluing and excellent bending resistance.

A flexible printed wiring board using the photosensitive film material for insulating a circuit board of the present invention as a cover lay,
It can be manufactured through the following essential steps. (1) A step of forming a circuit on the metal-clad laminate for a flexible printed wiring board, (2) A step of laminating the photosensitive film material of the present invention on the circuit-formed metal-clad laminate for a flexible printed wiring board. And (3) exposing and developing with an alkaline aqueous solution to form openings in the laminated photosensitive film material,
(4) A step of performing heat treatment for 1 minute or more at a temperature of 100 to 300 ° C.

In addition to the above-mentioned essential steps, it is of course possible to carry out washing, drying, drilling, plating or the like, if necessary. Further, the metal-clad laminate for a flexible printed wiring board can be applied to both a single-sided metal-clad laminate and a double-sided metal-clad laminate.

Another preferable use of the photosensitive film material of the present invention is commonly obtained by repeatedly forming an insulating layer on a conductor circuit and forming a new conductor circuit layer by sputtering or plating. An insulating material between the conductors of a sequential multilayer substrate called a build-up substrate can be given. This is because the photosensitive film material of the present invention has resistance to sputtering and plating treatment steps in addition to the above heat resistance and mechanical properties.

The sequential multilayer substrate using the photosensitive film material for insulating a circuit board of the present invention as an insulating material can be manufactured through the following essential steps. (1) a step of producing a material having a conductor circuit formed on an insulating substrate, (2) a step of laminating the photosensitive film material of the present invention on a material having a conductor circuit formed thereon, (3) exposure and A step of forming an opening in the laminated photosensitive film material by performing a developing treatment with an alkaline aqueous solution, and (4) performing a heat treatment at a temperature of 100 to 300 ° C. for 1 minute or more to cure the developed film material. The process of
(5) A step of forming the next conductor circuit layer on the cured film by plating, sputtering, vapor deposition, or a combination thereof.

The material on which the conductive circuit is formed on the insulating base material used here can also be produced by an etching method using a single-sided or double-sided metal-clad laminate as a starting material, and a composite material of glass cloth and polymer. It is also possible to directly form a conductor circuit on one surface or both surfaces of the polymer film by a method such as plating, sputtering, vapor deposition, or the like. In addition, by repeating the steps (2) to (5) among the above steps, it is possible to manufacture a sequential multilayer substrate in which three or more conductor layers are formed.

[0027]

EXAMPLES The present invention will be specifically described below based on examples, but the present invention is not limited thereto.

Synthesis Example 1 Bisphenol A-type epoxy resin (manufactured by Tohto Kasei Co., Ltd., Epotote YD-8125, epoxy equivalent 172 g)
/ Eq,) 34.0 parts by weight, acrylic acid 14.4 parts by weight,
0.05 parts by weight of tetraethylammonium bromide and 5.85 parts by weight of ethyl cellosolve acetate as a solvent were charged into a flask and stirred to obtain a uniform solution. This solution was reacted at 105 ° C. for 15 hours to obtain an epoxy acrylate compound. Then, the reaction solution was added with 7.6 of 1,2,3,6-tetrahydrophthalic anhydride as an acid anhydride.
Parts by weight and 20.5 parts by weight of ethylene glycol bistrimellitate dianhydride were added and reacted at 115 ° C. for 5 hours to obtain a viscous oligomer solution. The weight average molecular weight of the obtained oligomer by GPC analysis was 2,500.

Synthesis Example 2 Instead of 7.6 parts by weight of 1,2,3,6-tetrahydrophthalic anhydride and 20.5 parts by weight of ethylene glycol bistrimellitate dianhydride in Synthesis Example 1, ethylene glycol bistrimellitate was used. Synthesis was performed in the same manner as in Synthesis Example 1 using 41.0 parts by weight of dianhydride. The weight average molecular weight of the obtained oligomer was 3,800.

Synthesis Example 3 Synthesis was carried out in the same manner as in Synthesis Example 1 using 14.7 parts by weight of biphenyltetracarboxylic acid dianhydride instead of 20.5 parts by weight of ethylene glycol bistrimellitate dianhydride in Synthesis Example 1. I went. The weight average molecular weight of the obtained oligomer was 1,800.

Synthesis Example 4 Bisphenol A having different epoxy equivalents was used instead of 34.0 parts by weight of the bisphenol A type epoxy resin (Epototo YD-8125 manufactured by Tohto Kasei Co., Ltd.) of Synthesis Example 1.
Epoxy resin (Toto Kasei Co., Ltd., Epotote YD
-128, epoxy equivalent 192 g / eq, 38.0 parts by weight was used, and ethyl cellosolve acetate was used as a solvent in the same manner as in Synthesis Example 1 using 7.50 parts by weight. The weight average molecular weight of the obtained oligomer was 6,500.
Met.

Synthesis Example 5 34.0 parts by weight of bisphenol A type epoxy resin (Epototo YD-8125 manufactured by Tohto Kasei Co., Ltd.), 14.4 parts by weight of acrylic acid, 0.05 parts by weight of tetraethylammonium bromide and ethyl cellosolve. Acetate 5.8
5 parts by weight were placed in a flask and stirred to obtain a uniform solution. Then, the mixture was reacted at 105 ° C. for 15 hours to obtain an epoxy acrylate compound. The molecular weight of the obtained compound was 484. No reaction with acid anhydride was performed on this compound.

Example 1 50 parts by weight of the oligomer solution obtained in Synthesis Example 1 was added to a photopolymerization initiator (Ciba Geigy Co., Ltd., Irgacure 65).
1) 1 part by weight and 28.7 of a bisphenol A type epoxy resin (Epototo YD-901, manufactured by Tohto Kasei Co., Ltd.)
A part by weight was added to obtain a photosensitive composition. Using an applicator, this composition was coated on a polyethylene terephthalate (PET) film having a thickness of 50 μm, the surface of which was subjected to a mold release treatment, and dried at 60 ° C. for 30 minutes to give a substantially tack-free photosensitive film having a thickness of 50 μm. A transparent film was produced. Then, use this photosensitive film with a minimum circuit width of 100μ.
Single-sided copper-clad laminate with circuit formed in a shape of m and minimum circuit distance of 100 μm (Espanex S manufactured by Nippon Steel Chemical Co., Ltd.)
C35-40-00ME (electrolytic foil 35 μm / polyimide 40 μm)), with the PET film attached,
It laminated using the hot laminator apparatus (The Taisei Laminator Co., Ltd. make, Model 8B-550, temperature 80 degreeC, feed rate: 1 m / min) so that the photosensitive film and the circuit side of the single-sided copper clad laminated board might contact. At that time, the photosensitive film was filled without gaps between the circuits.

Next, an exposure machine (H-Tech Co., Ltd., H
TE-3000NEL) and the smallest unexposed part has a diameter of 1
The photosensitive film was exposed with an exposure amount of 300 mJ through a photomask having a size of 00 μm. After that, the PET film is peeled off and the temperature is 40 ° C. using a 5% sodium carbonate aqueous solution.
After developing for 1 minute, wash with pure water and
A heat treatment was performed at 60 ° C. for 60 minutes to obtain a flexible printed wiring board in which the patterned photosensitive film was configured as a coverlay. The pattern accuracy of the cover lay of the obtained flexible printed wiring board was 102 with respect to the diameter of 100 μm of the minimum unexposed portion of the photomask.
It was as good as μm.

The obtained flexible printed wiring board is used for 2
When immersed in a solder bath at 60 ° C. for 1 minute, no abnormalities such as swelling and peeling were observed. Further, even when the flexible printed wiring board was bent by 180 degrees, no crack was observed.

Example 2 The procedure was carried out except that 50 parts by weight of the oligomer solution obtained in Synthesis Example 2 was used as the oligomer component, and the development processing conditions were changed from 5% sodium carbonate 40 ° C. 1 minute to 2% sodium carbonate 40 ° C. 1 minute. Processed as in Example 1. The circuitability of the photosensitive film is good, and the pattern accuracy is 103
It was as good as μm. Moreover, the obtained flexible printed wiring board did not show any abnormality even when immersed in a solder bath, and was excellent in bending resistance.

Example 3 The same procedure as in Example 1 was carried out using 50 parts by weight of the oligomer solution obtained in Synthesis Example 3 as an oligomer component. The circuitability of the photosensitive film was good, and the pattern accuracy was 105 μm. Moreover, the obtained flexible printed wiring board did not show any abnormality even when immersed in a solder bath, and was excellent in bending resistance.

Example 4 The composition used in Example 1 was further treated with 5 parts by weight of triethylene glycol diacrylate and treated in the same manner as in Example 1. The circuitability of the photosensitive film was good, and the pattern accuracy was 101 μm. Moreover, the obtained flexible printed wiring board did not show any abnormality even when immersed in a solder bath, and was excellent in bending resistance.

Example 5 To 50 parts by weight of the oligomer solution obtained in Synthesis Example 4, 26.5 parts by weight of a brominated bisphenol A type epoxy resin (Epototo YDB-400 manufactured by Toto Kasei Co., Ltd.) and a photopolymerization initiator ( Ciba Geigy Co., Ltd., Irgacure 65
1) 1 part by weight and 5 parts by weight of triethylene glycol diacrylate were added and stirred for 1 hour to obtain a uniform composition. Then, using an applicator, this composition was applied to a polyethylene terephthalate (PET) film having a thickness of 50 μm, the surface of which was subjected to a mold release treatment, and dried at 80 ° C. for 5 minutes to give a substantially tack-free thickness of 40 μm. A photosensitive film was produced. Separately from this, a double-sided copper-clad laminate (Espanex SB35-5, manufactured by Nippon Steel Chemical Co., Ltd.)
0-35HR (copper foil 35μm / polyimide 50μm))
A circuit was formed so that the minimum circuit width was 100 μm and the minimum circuit distance was 100 μm. Photosensitive films were laminated on both sides of the double-sided copper clad board on which this circuit was formed, using the hot laminator device used in Example 1. that time,
The filling property between the circuits was good.

Next, using the exposure machine used in Example 1,
The photosensitive films on both sides were exposed with an exposure amount of 250 mJ through a photomask having a minimum unexposed area of 100 μm in diameter. After that, the PET film was peeled off, developed with a 5% sodium carbonate aqueous solution at 40 ° C. for 1 minute, washed with pure water, and heat-treated at 200 ° C. for 30 minutes to form a pattern. A double-sided flexible printed wiring board having a photosensitive film as a cover lay was obtained. The pattern accuracy of the coverlay of the obtained flexible printed wiring board was 103 μm, which was excellent with respect to the diameter of the minimum unexposed portion of the photomask of 100 μm.

When the obtained double-sided flexible printed wiring board was immersed in a solder bath at 260 ° C., no abnormality such as swelling or peeling was observed. In addition, no crack was observed even after bending 180 degrees.

Example 6 To 50 parts by weight of the oligomer solution obtained in Synthesis Example 1, 18.5 parts by weight of brominated phenol novolac type epoxy resin (Bren-S manufactured by Nippon Kayaku Co., Ltd.) and tripropylene glycol diacrylate were added. 5 parts by weight and 1 part by weight of a photopolymerization initiator were added and stirred for 1 hour to obtain a uniform composition. Next, this composition was applied to a polyethylene terephthalate (PET) film having a thickness of 50 μm, the surface of which was subjected to mold release treatment, using an applicator, and the composition was applied at 60 ° C. for 30 minutes.
After being dried for a minute, a photosensitive film having a thickness of 50 μm and having substantially no tack was produced.

A glass epoxy single-sided copper clad plate (R17 manufactured by Matsushita Electric Works, Ltd.) on which a circuit is formed from this photosensitive film.
00, copper foil 18 μm / glass epoxy 300 μm) was laminated using the hot laminator apparatus used in Example 1. Next, using the exposure machine used in Example 1, the photosensitive film was exposed with an exposure amount of 300 mJ through a photomask having a minimum unexposed portion with a diameter of 70 μm. After that, the PET film was peeled off, subjected to a development treatment with a 5% sodium carbonate aqueous solution at 40 ° C. for 1 minute, washed with pure water, and heat-treated at 200 ° C. for 15 minutes to form an insulating layer. The precision of the opening of the obtained insulating layer was 72 μm, which was excellent with respect to the diameter of 70 μm of the minimum unexposed portion of the photomask.

Then, a second-layer circuit having a thickness of 18 μm was formed on the insulating layer obtained from the photosensitive film by electroless plating. At that time, electrical continuity was established between the first and second circuits through the openings in the insulating layer.

Furthermore, lamination of a photosensitive film, formation of an insulating layer by exposure, development, and heat treatment, and circuit formation by plating are repeated twice to form a sequential multilayer substrate having a total of four circuit layers, and then a photosensitive layer is formed. A film was used to form a protective layer on the surface. The filling property between the circuits of the insulating layers of the obtained sequential multilayer substrate was good. No abnormality was found in the solder resistance test.

Comparative Example 1 A composition was obtained by adding 1 part by weight of a photopolymerization initiator to 50 parts by weight of the compound solution prepared in Synthesis Example 5. The thickness of this composition which has been release-treated with an applicator 5
It was applied to a 0 μm polyethylene terephthalate (PET) film and dried at 60 ° C. for 30 minutes to produce a film having a thickness of 50 μm and substantially no tack. Then
This film was laminated with the hot laminator apparatus used in Example 1 while the PET film was stuck on the circuit-formed one-sided copper clad plate used in Example 1. At that time, the film was filled without gaps between the circuits.

Next, using the exposure machine used in Example 1,
The photosensitive film was exposed through a photomask having a minimum unexposed area of 100 μm in diameter so that the exposure amount was 300 mJ. After that, the PET film was peeled off, and a development treatment was performed at 40 ° C. for 1 minute using a 5% sodium carbonate aqueous solution. However, since the compound used here did not react with an acid anhydride, it was not possible to develop a pattern even if the development treatment with an aqueous sodium carbonate solution was carried out.

Comparative Example 2 The composition used in Example 2 was applied as a solution directly onto the circuit-formed single-sided copper clad plate used in Example 1 by spin coating, and the composition was applied at 60 ° C. for 30 minutes. It was dried to form a layer of the photosensitive composition. At this time, uneven coating was confirmed because it was directly coated on the copper clad plate on which the circuit was formed. Hereinafter, Example 2
In the same manner as above, exposure, development and heat treatment were performed to obtain a flexible printed wiring board. The obtained flexible printed wiring board had good soldering resistance and bending resistance, but had a large warp and was not practically usable.

[0049]

EFFECT OF THE INVENTION The photosensitive film material of the present invention enables precise patterning with an alkaline aqueous solution, is excellent in filling in a circuit, and is also excellent in heat resistance and mechanical properties. Therefore, it is extremely useful as an industrial material such as a coverlay of a flexible printed wiring board and an insulating material of a sequentially multilayered substrate. Further, a flexible printed wiring board or a sequential multilayer substrate using the photosensitive film material of the present invention as a cover lay material or an interlayer insulating material has good heat resistance and does not show any abnormality even when immersed in a solder bath, Also,
It also has excellent mechanical properties such as bending resistance.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Chiaki Asano 3-7-5 Kasumi, Narashino-shi, Chiba (72) Inventor Hideyasu Asakage 2-25 Nishimizue, Edogawa-ku, Tokyo (72) Inventor Hobun, Yoshimoto Kanagawa 2-19-20 Minamiikuta, Tama-ku, Kawasaki-shi, Japan

Claims (8)

[Claims] 1. An oligomer obtained by reacting an epoxy acrylate compound represented by the following general formula (1) with an acid anhydride and a compound having an epoxy group as essential components, and the oligomer and epoxy group A photosensitive film material for insulating a circuit board, which is formed from a composition having a weight ratio of the compound to the range of 0.1 to 10. Embedded image (In the formula, X represents a divalent group or absent, and n is 1 to 10).
Represents the number of R _{1 to} R ₈ represent a hydrogen atom, an alkyl group or a halogen atom, and each may be the same or different, and R ₉ represents a hydrogen atom or a methyl group.) 2. The photosensitive film material for insulating a circuit board according to claim 1, wherein a part or all of the epoxy acrylate compound is a compound in which X in the general formula (1) is a 2-propylidene group. 3. The photosensitive film material for insulating a circuit board according to claim 1, wherein a part or all of the compound having an epoxy group is a compound containing a bromine atom. 4. The photosensitive film material for insulating a circuit board according to claim 1, wherein a part or all of the acid anhydride is ethylene glycol bistrimellitate dianhydride. 5. A flexible printed wiring board using the photosensitive film material for insulating a circuit board according to claim 1 as a cover lay material. 6. A sequential multi-layer substrate comprising the photosensitive film material for insulating a circuit board according to claim 1 as an interlayer insulating material of the multi-layer substrate. 7. A method for manufacturing a flexible printed wiring board, which comprises the following steps as essential steps. (1) A step of forming a circuit on a metal-clad laminate for a flexible printed wiring board, (2) A metal-clad for a flexible printed wiring board on which the photosensitive film material for insulating a circuit board according to claim 1 is formed. Laminating on a laminated plate, (3) exposing and developing treatment with an alkaline aqueous solution to form an opening in the laminated photosensitive film material, (4) 1 at a temperature of 100 to 300 ° C.
A step of performing heat treatment for more than a minute. 8. A method for manufacturing a sequential multilayer substrate, which comprises the following steps as essential steps. (1) a step of producing a material having a conductor circuit formed on an insulating base material; (2) laminating the photosensitive film material for insulating a circuit board according to claim 1 on the material having a conductor circuit formed thereon. Step, (3) exposing and developing treatment with an alkaline aqueous solution to form an opening in the laminated photosensitive film material, (4) performing heat treatment for 1 minute or more at a temperature of 100 to 300 ° C., Curing the developed film material, (5) forming a next conductor circuit layer on the cured film by plating, sputtering, vapor deposition or a combination thereof.