WO2002100139A1

WO2002100139A1 - A method of forming flexible insulation protection film of flexible circuit board and flexible circuit board formed with flexible insulation protection film and production method therefor

Info

Publication number: WO2002100139A1
Application number: PCT/JP2002/005415
Authority: WO
Inventors: Hiroshi Orikabe; Kouichirou Sagawa
Original assignee: Ajinomoto Co., Inc.
Priority date: 2001-06-01
Filing date: 2002-06-03
Publication date: 2002-12-12

Abstract

A method of forming a flexible insulation protection film of a flexible circuit board, which satisfies various characteristics required for the coating materials of a flexible circuit board, and which is characterized by comprising the steps of forming, into a thermosetting resin composition film via thermosetting resin composition varnish, a thermosetting resin composition that contains an A component compound having a specified number average molecular weight and a specified functional group equivalent weight, and a B component compound having a specified number average molecular weight and a specified functional group equivalent weight, and that has an average of combined functional group equivalent weights of the A component compound and the B component compound of 300-1200 g/eq., and of pasting the thermosetting resin composition film to the flexible circuit board.

Description

Method of forming flexible insulating protective film of flexible circuit fiber and

Flexipole circuit scythe with flexible insulating protective film

(Technical field)

The present invention relates to a method for forming a flexible insulating protective film of a flexible circuit having a fine pitch, comprising forming an insulating protective film using a flexible thermosetting resin material film (described later). The present invention relates to a flexible circuit having a flexible insulating protective film formed by this method.

(Background technology)

The flexible circuit board that can be implemented by bending in tight spaces, reel • toe -. Reel due _{_(ree} i _to _ree i) by that it is capable of continuous production, high density of the printed wiring board, thickness, production It is suitable for improving the efficiency of the system. For this reason, in recent years, this flexible circuit countermeasure has begun to be applied to IC package design in the form of TAB, COF, T-BGA, and the like.

As the insulating protective film used for TAB, COF, T-BGA, etc., a thermosetting type or a photocuring / developing type liquid solder resist is used. As such a liquid solder resist, a thermosetting or photocurable resin composition mainly containing an epoxy resin, a acryl resin, or the like is generally used. Recently, urethane-based thermosetting resin compositions having excellent flexibility as disclosed in JP-A-11-61037, JP-A-11-61038 and JP-A-11-71551 have also been proposed.

However, such as IC packages such as TAB, COF, and T-BGA, If liquid solder-resist is used as an insulating protective film for the fine pitch circuit, the ink tends to flow out due to the capillary phenomenon between the wirings during coating and curing.

For example, in the case of a flexible circuit board having a fine pitch between conductors of 30 m or less, it is no longer possible to suppress the flow amount to 50 m or less, which hinders the design of a high-density circuit board. Become.

In addition, when a development type photosensitive resin (photocurable resin composition) is used for the liquid solder resist, a bleeding portion (flow-out) can be removed by development, but the development type photosensitive resin (photocuring resin) can be removed. However, the curable resin composition) becomes a relatively hard coating film after curing, and exhibits a large warpage due to curing shrinkage, so that it cannot be applied to the application for bending and mounting.

On the other hand, as a method of forming an insulating protective film of a flexible circuit fiber, a method of using a film-like coverlay obtained by applying an adhesive to a polyimide film is also known.

However, such a method using a coverlay is not suitable for thinning because the polyimide film used for the force laylay film is hard, cannot obtain sufficient bending properties, and has an adhesive layer. Was difficult. Therefore, in a method of forming an insulating protective film of a flexible circuit having a fine pitch, such as an IC package such as a TAB, a COF, or a T-BGA, a method using such a coverlay has been used. There is no example.

In the future, IC packages such as TAB, COF, and T-BGA are expected to become more fine-pitch, and a flexible circuit capable of responding to such advanced fine-pitch formation of a flexible insulating protective film There is a need for method development.

(Disclosure of the Invention) An object of the present invention is to provide a method for forming an insulating protective film on a flexible circuit board, wherein the insulating protective film has excellent flexibility and can highly suppress the amount of resin flowing out when forming the insulating protective film. The aim is to develop a method that excels in forming an insulating protective film on a fine pitch circuit board such as an IC package such as TAB, COF, or T-BGA. The present inventor has conducted intensive studies to achieve the above object, and as a result, a specific thermosetting resin composition was converted into a flexible thermosetting resin composition film through a thermosetting resin composition varnish. It has been found that the above object is achieved by curing the film after laminating the film to the flexible circuit board, and the present invention has been completed based on such knowledge.

That is, the present invention relates to at least one compound selected from the group consisting of the following Al, A2 and A3 (component A) and at least one compound selected from the group consisting of the following Bl, B2 and B3 A thermosetting resin composition containing (B component) and having an average functional group equivalent of 300 to 1,200 g / eq. Of the combined A component compound and B component conjugate. A flexible thermosetting resin composition film is formed through a flexible resin composition varnish, and the flexible thermosetting resin composition film is bonded to a flexible circuit board. The present invention relates to a method for forming a film.

A1: a compound having a number average molecular weight of 1,000 to 8,000 and a functional group equivalent in the range of 100 to 4,000 g / eq.

A2: a compound having a number average molecular weight of 13,000 to 30,000 and a functional group equivalent of 1,300 to 15,000 g / eq.

A3: Compound having a number average molecular weight of 200 to 1,200 and a functional group equivalent in the range of 20 to 400 / eq. B 1: The number average molecular weight is 1,000 to 8,000, and it has a Kanakura group that can react with any of A 1 to A 3, and its g is equivalent to 100 to 4,000 g / eq. Is a compound,

B2: having a number average molecular weight of 13,000 to 30,000, having a functional group capable of reacting with any of A1 to A3, and having a functional group equivalent of 1,300 to: L 5,000 g / eq. The compound which becomes.

B3: a compound having a number average molecular weight of 200 to 1,200, a functional group capable of reacting with any of A1 to A3, and a functional group equivalent of 20 to 400 da6 (1. The present invention will be described in detail below with reference to a flexible circuit in which a flexible insulating protective film is formed by a simple method.

It is important that the flexible thermosetting resin composition film used in the present invention has a small shrinkage upon curing and imparts sufficient flexibility to the cured product. Therefore, as a method for imparting these properties, the present invention specifies the molecular weight and the functional group equivalent of the compound that is a component of the film. Hereinafter, first, the resin composition as a raw material of such a film will be described in detail. In the present invention, a compound Al having a number average molecular weight of 1,000 to 8,000 and a functional group equivalent in the range of 100 to 4,000 g / eq., And a number average molecular weight of 1,000 to 8,000. The compound B1, which has a functional group capable of reacting with any of the compounds A1 to A3 and has a functional group equivalent in the range of 100 to 4,000 g / eq., Is a characteristic of a densely cured resin. Heat resistance and chemical resistance, as well as flexibility and low shrinkage, which are characteristics of sparsely cured resins, are important for imparting a good balance to the formed insulating protective film. If the molecular weight or functional group equivalent is smaller than this range However, since the crosslink density at the time of curing becomes high, it becomes a harder cured product, which causes problems such as impairing the flexibility of the formed coating film (insulating protective film) and increasing shrinkage at the time of curing. On the other hand, if the molecular weight or the functional group equivalent is larger than this range, the crosslink density at the time of curing becomes low, so that a more flexible cured product is obtained, but the heat resistance and chemical resistance of the obtained coating film are significantly reduced. I do.

In the present invention, compound A2 having a number average molecular weight of 13,000 to 30,000 and a functional group equivalent in the range of 1,300 to 15,000 g / eq., And a number average molecular weight of 13,000 to 30 The compound B2, which has a functional group capable of reacting with any of the compounds A1 to A3 and has a functional group equivalent in the range of 1,300 to: L 5,000 g / eq. It is useful for improving the flexibility of the cured product as a protective film and for reducing shrinkage during curing.

In the present invention, a compound A3 having a number average molecular weight of 200 to 1,200 and a functional group equivalent in the range of 20 to 400 g / eq., And a compound A1 to 200 having a number average molecular weight of 200 to 1,200. Compound B3, which has a functional group capable of reacting with any of A3 and has a functional group equivalent in the range of 20 to 400 g / eq., Increases the crosslink density of the cured product, so that it has heat resistance and chemical resistance. It has the effect of imparting properties such as properties.

When an insulating protective film is formed by reacting and curing only compound A 3 and compound B 3, the crosslink density increases, the flexibility of the resulting coating film is impaired, and the shrinkage during curing increases, resulting in a flexible circuit. Sufficient characteristics cannot be obtained as an insulating protective film for a substrate. On the other hand, when the reaction is cured only with the compound A 2 and the compound B 2, on the other hand, the cross-linking density is remarkably reduced, and the resulting coating film has poor properties as an insulating protective film, such as properties and chemical resistance.

In order to satisfy all of the flexibility, shrinkage reduction, heat resistance, and chemical resistance of the coating film, two kinds of compounds having such different properties are used by mixing in an appropriate range. It is necessary. The same applies to combinations of other innumerable compounds. In order to obtain a balance between properties that can be satisfied with the cured product, the A component compounds A1 to A3 and the B component For example, from the two types of compounds B 1 to B 3, it is necessary to select, for example, two or more types, and to use them together in an appropriate mixing ratio to effect a curing reaction. The properties of the cured product are attributed to the crosslink density of the cured product, and the crosslink density is determined by the functional group equivalent of the compound before the reaction. It is necessary to pay attention to the average value of the equivalent. Specifically, for a curable resin composition composed of a plurality of optional component A compounds and a plurality of optional component B compounds, the average of the functional group equivalents of the two component compounds is set to 300 to It is important to be in the range of 1,200 g / eq., And more preferably, in the range of 500 to 1,000,000 g / eq.

If the average value of the functional group equivalents is larger than this range, the cross-linking density of the resulting coating film (insulating protective film) will be too low, and the heat resistance and chemical resistance will be impaired. Too much flexibility will be impaired and shrinkage during curing will increase. Conversely, even when a plurality of compounds are not used for each of the A component compound and the B component compound, such as a combination of any one of the compound A 1 and any one of the compounds B 1, If it falls within the above-mentioned equivalent range, it is not necessary to dare to make a multi-component composition.

In short, a thermosetting resin composition in which at least one of the component A compounds is used in combination with at least one of the component B compounds, and the average value of the functional group equivalents of the two component compounds combined Is within the above range.

In the present invention, since the thermosetting of the thermosetting resin composition is caused by the heat curing reaction of the component A and the component B, both component compounds are mutually equivalent in the same functional equivalent weight. However, it is not necessary that the number of equivalents be exactly the same, and in terms of the number of functional group equivalents, the component A compound to the component B compound-1/3 to 3, preferably 1/2 To 2, more preferably 2/3 to 3/2. Here, the functional group equivalent number can be represented by (weight of component A compound (g)) / (functional group equivalent of component A compound (g / eq.)) In the case of the component A compound.

When a resin having any of a polybutadiene skeleton, a hydrogenated polybutylene skeleton, a polysiloxane skeleton, a polyethylene glycol skeleton, a polypropylene skeleton, and a polyisoprene skeleton is used as the A component compound or the B component compound, Flexibility can be imparted to the obtained coating film (insulating protective film), which is more preferable. On the other hand, it is more preferable to use a resin having a polyester skeleton for the A component compound or the B component compound, since the adhesion to the sealing resin on the underlying wiring board or insulating protective film is improved. However, polyester resins have a drawback that they are easily susceptible to hydrolysis.Therefore, polyester resins have a polybutadiene skeleton, a hydrogenated polybutadiene skeleton, a polysiloxane skeleton, a polypropylene skeleton, or a polyisoprene skeleton having high j properties. It is preferable to use the resin in combination to prepare the thermosetting resin composition. Further, usually, many polyester resins are bifunctional. Therefore, it is more preferable that a resin used in combination with the polyester resin has at least trifunctionality or more.

In addition, the following three kinds of compounds: (a) a bifunctional hydroxyl-terminated polybutadiene having a number average molecular weight of 800 to 50,000, (b) a tetrabasic acid represented by the following general formula (1) An anhydride, and (c) a modified polyimide resin represented by the following general formula (3) obtained by reacting a diisocyanate compound represented by the following general formula (2), and a thermosetting material for forming an insulating protective film. When used in any of the components of the resin composition, the imide skeleton exhibits heat resistance, and the butadiene skeleton exhibits flexibility, so that both properties can be imparted to the insulating protective film in a well-balanced manner. preferable. Further, since the modified polyimide resin is a linear polymer and has a reaction point only at both ends, it is more preferable that the resin used in combination with the resin has at least trifunctionality or more. (1)

(R1 represents a residue obtained by removing a carboxyl group from an organic compound having four carboxyl groups.)

0CN R2—— NC0 (2)

(R2 represents a residue obtained by removing the isocyanate group from an organic compound having two isocyanate groups.)

(3)

(R1 is a residue obtained by removing the carboxyl group from an organic compound having four carboxyl groups, R2 is

The residue obtained by removing the isocyanate group from an organic compound having two CO isocyanate groups, and R3

Represents a residue obtained by removing the hydroxyl group from hydroxyl-terminated polybutadiene. _X and y each represent the composition ratio of the polybutadiene unit and the polyimide unit, and π represents the degree of polymerization. At this time, x + y = K0 <x <1 _H 0 <y <1 \ ^, 1≤n≤10,000. )

On the other hand, the functional groups possessed by the A component compound and the B component conjugate include a 7_K acid group, a block isocyanate group, a propyloxyl group, an epoxy group, an acid anhydride group, a mercapto group, a hydrazide group, and an amino group. And a blocking lipoxyl group. In addition, any combination of the functional groups possessed by the 化合物 -component compound and the Β-component compound can be used as long as they can react with each other, but among them, the combination of the hydroxyl group and the proxocyanate group is flexible. It is more preferable for imparting properties.

Compound A1 and Compound B1 have a number average molecular weight of 1,000 to 8,000 and a functional group equivalent of 100 to 4,000 g / eq. Any functional group can be used as long as the functional group is reactive, such as a hydroxyl group, a broxocyanate group, a propyloxyl group, an epoxy group, an acid anhydride group, a mercapto group, a hydrazide group, an amino group, or a carboxyl group. Anything is fine.

Examples of such a compound having a hydroxyl group include acryl polyol obtained by copolymerizing an olefin having a hydroxyl group such as vinyl alcohol and aryl alcohol with another olefin, a polyether diol, and a molar ratio during polymerization. The above molecular weight and the number of hydroxyl groups in the column such as polyester polyols with hydroxyl groups remaining at the ends by shifting the polyolefin resin, and polybutadiene, hydrogenated polybutadiene, polyolefin, polysiloxane, polyisoprene, etc. Everything that satisfies is listed. Acrylic polyols include “Desmophen A665” (manufactured by Sumitomo Bayer Urethane Co., Ltd.) and polyester polyols include “HM-1” (manufactured by Arakawa Chemical Industries, Ltd.) and "Elitel UE 3320" (manufactured by Unitika Ltd.), and hydroxyl group-containing polybutadienes include "G100" and "GQ100" (both manufactured by Nippon Soda Co., Ltd.), hydroxyl group Examples of hydrogenated polybutadiene include “GI100” (manufactured by Nippon Soda Co., Ltd.), and examples of hydroxyl-containing polyolefins include Polyter H (manufactured by Mitsubishi Iridaku Co., Ltd.). I can do it. Above all, in order to impart more flexibility, hydroxyl group-containing polybutene, hydroxyl group-containing hydrogenated polybutadiene, hydroxyl group-containing polysiloxane, polyethylene glycol, hydroxyl group-containing polyisoprene, and the like are preferable.

In addition, as such a compound having a block isocyanate group, among the above-mentioned resins belonging to the polyol, a bifunctional resin is reacted with polyisocyanate to obtain an isocyanate group-containing resin. After that, a product obtained by blocking the isocyanate group with a blocking agent, or an isocyanate-containing acrylate such as 2-methacryloyloxyshethyl isocyanate and another monomer having a double bond are added thereto. Examples include those obtained by appropriately polymerizing and adjusting the molecular weight and the number of functional groups to a specified value, and then blocking an isocyanate group with a blocking agent. Above all, in order to impart more Qin flexibility, it is preferable to contain a molecular skeleton such as polybutadiene, hydrogenated polybutadiene, polysiloxane, polyethylene glycol, and polyisoprene. (Manufactured by Nippon Soda Co., Ltd.) and "Η-Τ-9" (manufactured by Idemitsu Petrochemical Co., Ltd.), and the like, obtained by blocking an isocyanate group-containing resin with a blocking agent. The blocking agent used here is a compound having only one active hydrogen in one molecule capable of reacting with the isocyanate group, and is 170 even after reacting with the isocyanate group. It is preferable to dissociate again at a temperature of C or lower, and examples thereof include prolactam, getyl malonate, acetyl acetate, acetoxime, methylethylketoxime, phenol, and cresol.

Examples of such a compound having a carboxyl group include, for example, polyacrylic acid obtained by copolymerizing acrylic acid and other olefins, and alcohol and the like to an acid anhydride group of maleic anhydride-modified polybutane. Examples thereof include those in which a hydroxyl group is formed by addition, and a carboxyl group-terminated butadiene acrylonitrile copolymer. Examples of polyacrylic acid include “John Krill J 6 82 j and “John Krill J 586” (both manufactured by Johnson Polymer Co., Ltd.). A carboxyl group is formed by adding an alcohol or the like to an acid anhydride group of a modified maleic anhydride polybutadiene. The carboxyl group was formed by adding an alcohol or the like to the acid anhydride group of maleic anhydride-modified polybutadiene such as “Laicon 130MA13” and “Laicon 131MA17” (both manufactured by Raicon Resin Co., Ltd.). Examples of such a copolymer include a “hiker CTB N 1300 X8” (manufactured by Ube Industries, Ltd.) and the like.

Examples of such a compound having an epoxy group include "BF100" (manufactured by Nippon Soda Co., Ltd.). Further, "B-100" (Nippon Soda Co., Ltd.) Epoxidized hydrogenated polybutadiene obtained by partially ice-adding double bonds in a polybutene homopolymer having an average molecular weight of about 1,000, such as the product manufactured by Sharp Corporation, and then epoxidizing the remaining double bonds. And hydrogenated polybutadiene polyol with an average molecular weight of about 1,000, such as GI-1000 (manufactured by Nippon Soda Co., Ltd.), and diisocyanate such as 2,4-tolylene diisocyanate The compound was charged in an amount equivalent to twice the equivalent of the hydroxyl group and reacted so that an isocyanate group was left at the terminal. Further, "Eviol G-100" (manufactured by NOF Corporation) was added to the product. ) One hydroxyl group in one molecule such as One epoxidized hydrogenated polybutadiene obtained by the epoxy compound is added can be mentioned.

Examples of such a compound having an acid anhydride group include modified maleic anhydride polybutene, such as "Laicon 130MA13" and "Laicon 131MA17" (both manufactured by Laicon Resin Co., Ltd.).

Compound A 2 and Compound B 2 may have any number as long as the number average molecular weight is 13,000 to 30,000 and the functional group equivalent is 1,300 to 15,000 g / eq. Hydroxyl, block isocyanate, carboxyl, epoxy Any reactive group such as a xy group, an acid anhydride, a mercapto group, a hydrazide group, an amino group, and a carboxylic group may be used.

For example, such a compound having a hydroxyl group includes acryl polyol, a polyether polyol obtained by copolymerizing an olefin having a hydroxyl group such as vinyl alcohol and aryl alcohol with another olefin, a polyether polyol, and the molar ratio at the time of polymerization is shifted. The above molecular weight and number of hydroxyl groups are satisfied with polyester polyols with hydroxyl groups remaining at the terminals, and resins such as polybutadiene, hydrogenated polybutadiene, polyolefin, polysiloxane, polyisoprene, etc., which are denatured to introduce hydroxyl groups. Everything can be mentioned. As acrylic polyol, “Desmophen A450_ | (manufactured by Sumitomo Bayer Urethane Co., Ltd.)”, and as polyester polyester, “Pylon—200” (manufactured by Toyobo Co., Ltd.) ) And “Elitel UE 360” (manufactured by Unitika Ltd.), and as the hydroxyl group-containing polyisoprene, “LIR506” (manufactured by Kuraray Co., Ltd.) and the like can be mentioned. In addition, for example, a part of the hydroxyl group of the compound A1 or the compound B1 described above is cross-linked with polyisocyanate, polycarboxylic acid, or polyanhydride to obtain a bush average molecular weight of 13, Included are those that have been increased to 0 0 0-3 0, 0 0 0. Above all, in order to provide more flexibility, a hydroxyl group-containing polybutene having a number average molecular weight of 1,000 to 8,000, a hydroxyl group-containing hydrogenated polybutene, a hydroxyl group-containing polysiloxane, and polyethylene glycol Some of the hydroxyl groups such as hydroxyl group-containing polyisoprene are cross-linked with polyisocyanate, polycarboxylic acid, polyanhydride, etc., and the number average molecular weight is 13, 00 00 to 30, 00 0 0 It is preferable to increase the number up.

Examples of such a compound having a block isocyanate group include compounds having an average molecular weight of 3.0000, such as "G-30000_j" (manufactured by Nippon Soda Co., Ltd.).

Diisocyanate compound such as 2,4-tolylene diisocyanate is charged to polybutadiene polyol of about 0 in the range of 1 to 2 equivalents to hydroxyl equivalents. The molecular weight is about 13, 000 to 30, 000, the molecular weight is increased so that the isocyanate group remains at the terminal, and then the remaining isocyanate group is blocked with a blocking agent. be able to. The blocking agent used here is a compound that has only one active hydrogen in one molecule that can react with the isocyanate group, and dissociates again at a temperature of 100 ° C or less even after reacting with the isocyanate group. And e-caprolactam, getyl malonate, ethyl acetoacetate, acetoxime, methylethyl ketoxime, phenol, cresol, and the like.

Examples of such a compound having a carboxyl group include a polybutadiene polyol having an average molecular weight of about 3,000, such as “G-300j (manufactured by Nippon Soda Co., Ltd.). Then, a diisocyanate compound such as 2,4-tolylene diisocyanate is charged in a range of 0.5 to 1 equivalent to the hydroxyl equivalent, and the molecular weight is 13, 000 to 30, After increasing the molecular weight so that the hydroxyl group remains at the terminal at about 0.00, further add an acid anhydride compound such as trimellitic anhydride to the product in an amount equivalent to 7 acid group equivalents. Polybutadiene polycarboxylic acid obtained by reaction so that a carboxyl group remains at the terminal, or an average molecular weight of about 3,000, such as “GI300” (manufactured by Nippon Soda Co., Ltd.). Hydrogenated polybutene, 2,4-tolylenediamine A diisocyanate compound such as a nitrate is charged within the range of 0.5 to 1 equivalent to the hydroxyl equivalent so that the molecular weight is about 13,000 to 30,000 and the hydroxyl group remains at the terminal. Then, an acid anhydride compound such as trimellitate anhydride is charged to the product in the same equivalent amount as the hydroxyl group equivalent and reacted so that a carboxyl group remains at the terminal. And hydrogenated polybutene polycarboxylic acid.

Examples of such a compound having an epoxy group include polybutadiene having an average molecular weight of about 3,000 such as "G-300" (manufactured by Nippon Soda Co., Ltd.). A diisocyanate compound such as 2,4-tolylene diisocyanate is charged to the diene polyol in an amount of 1 to 2 equivalents to the equivalent of the hydroxyl group, and the molecular weight is about 13,000 to 30,000. After increasing the molecular weight so that the isocyanate group remains at the end, an epoxy compound having one hydroxyl group in one molecule such as “Eviol G-100” (manufactured by NOF CORPORATION) is added to the product. The hydrogenated polybutadiene polyol having an average molecular weight of about 3,000 o: 0, such as epoxidized boributadiene o: obtained by the reaction and “GI-3000” (manufactured by Nippon Soda Co., Ltd.) (4) A diisocyanate compound such as tolylene diisocyanate is charged in a range of 1 to 2 equivalents to a hydroxyl equivalent, and the molecular weight is about 7,000 to 35,000, and an isocyanate group remains at a terminal. After high molecular weight Furthermore, an epoxidized hydrogenated polybutadiene obtained by adding an epoxy compound having one hydroxyl group in one molecule such as “Epiol G-100” (manufactured by NOF Corporation) to this product. Can be mentioned.

Examples of such a compound having an acid anhydride group include, as described above, a bifunctional hydroxyl-terminated polybutadiene having a number average molecular weight of 800 to 5,000, and the following general formula (1): A modified polyimide resin represented by the following general formula (3) obtained by reacting a tetrabasic acid anhydride with three compounds of a diisocyanate compound represented by the following general formula (2) can be exemplified.

0,, R1 0 (1)

0 0

(R1 represents a residue obtained by removing the carboxyl group from an organic compound having four carboxyl groups.) OCN R2—— NCO (2)

(3)

(R1 is a residue obtained by removing the carboxyl group from an organic compound having four carboxyl groups, R2 is a residue obtained by removing the isocyanate group from an organic compound having two isocyanate groups, and R3 is a hydroxyl-terminated polybutadiene. Represents a residue excluding the hydroxyl group thereof, and X and y each represent a ratio of a polybutadiene unit to a polyimide unit, and n represents a degree of polymerization, where x + y-1, 0 <x < 1, 0 <y <1, and 1≤n≤10,000.)

Examples of the acid anhydride represented by the general formula (1) used in the production of the modified polyimide resin include pyromellitic dianhydride, benzophenonetetracarboxylic dianhydride, and biphenyltetracarboxylic acid. Examples thereof include, but are not limited to, dianhydride and naphthylenetetracarbonate dianhydride. Examples of the diisocyanate compound represented by the general formula (2) include toluene-12,4-diisocyanate, toluene-12,6-diasocyanate, hexamethylenediisocyanate, xylylenediisocyanate, and diphenylmethanedienyl. Examples thereof include, but are not limited to, succinates and isophorone diisocyanate. As such a modified polyimide resin, specifically, for example, polybutadiene polyol having an average molecular weight of about 3,000 such as “G-300” (manufactured by Nippon Soda Co., Ltd.) Then, a diisocyanate compound such as 2,4-tolylene diisocyanate is charged within a range of 1 to 2 equivalents to a hydroxyl equivalent, to give a molecular weight of 13,000 to 30,000. After increasing the molecular weight to leave an isocyanate group at the end of the product, a difunctional acid anhydride compound such as benzophenonetetracarboxylic dianhydride is further added to the product by 2 equivalents to the hydroxyl equivalent. It includes those obtained by reacting so that an acid anhydride group remains at the terminal by charging double equivalents, and further having an average molecular weight of 3,000, such as "G1-300000". 2,4-tolylenedioxide to moderately hydrogenated polybutene gen polyol A diisocyanate compound such as a monovalent compound is charged within a range of 1 to 2 equivalents to a hydroxyl equivalent, so that the molecular weight is about 13,000 to 30,000 and an isocyanate group is left at a terminal. after molecular weight, the more the product, a difunctional acid anhydride compound such as benzophenone tetracarboxylic acid dianhydride, ² equivalents amount corresponding charged at terminal acid anhydride group relative to the hydroxyl group equivalent of Examples thereof include hydrogenated polybutyric acid polyanhydride and the like obtained by allowing the reaction to remain.

Furthermore, the compound A3 and the compound B3 have a number average molecular weight of 200 to Any number is acceptable as long as the number of functional groups is 1,200 and the functional group equivalent number is 20 to 400/6/6. The functional groups are also hydroxyl groups, bromoisocyanate groups, carboxyl groups, epoxy groups, and acid anhydrides. Any group having reactivity, such as a group, a mercapto group, a hydrazide group, an amino group, and a carboxyl group, may be used.

For example, examples of such a compound having a hydroxyl group include “PE555” (manufactured by Toho Chemical Co., Ltd.), an EO-modified pennin erythritol, and “TP88Oj (manufactured by Toho Chemical Co., Ltd.). And “Placcel 303” and “Placcel 300” (both manufactured by Daicel Chemical Industries, Ltd.), which are polyprolactone riol, respectively.

Such a compound having a block isocyanate group is obtained by blocking a polyisocyanate having two or more functionalities with a blocking agent, and the isocyanate compound used herein is toluene. Diisocyanates such as 2,4-diisocyanate, toluene-1,2,6-diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, and isophorone diisocyanate.ゃ, those obtained by making the above-mentioned disocyanate trifunctional or more by using the diisocyanate reaction of the isocyanate group, or those obtained by reacting a part of the isocyanate group with various polyols to make it more than trifunctional Active hydrogen that can react with the isocyanate group in one molecule is used as a blocking agent. It is preferable that the compound has only one of the following groups, and that it dissociates again at a temperature of 100 ° C or less even after reacting with the isocyanate group. —Caprolactam, dimethyl ethyl malonate, ethyl acetyl acetate, acetoxime, methylethyl Ketoxime, phenol, cresol and the like can be mentioned.

Examples of such a compound having a carboxyl grave include “Rikasid: BT-I-W” (manufactured by Shin Nihon Ridani Co., Ltd.) and “Rikasid TMT A—C” (Shin Nihon Rika

Products produced by adding alcohol, etc. to carboxyl groups Can be mentioned.

For example, epoxy resins having an epoxy group include bisphenol A type epoxy resins “Epicoat 828” and “Epicoat 157” (both manufactured by Japan Epoxy Resin Co., Ltd.), and “Denacol EX 611” (Nagase Kasei Kogyo ( Co., Ltd.).

For example, examples of such a compound having an acid anhydride group include “Rikasid TMT A-C” (manufactured by Shinnihon Ridani Co., Ltd.). In addition, such resins as “IPU — 22ΑΉ” (manufactured by Okamura Oil Co., Ltd.) that have been polymerized to a high molecular weight through acid anhydride bonds repeatedly dissociate and react with each other during curing. Resins that have a number average molecular weight of 200 to 700 repeating units and a functional group equivalent within the range of 20 to 400 g / eq. In addition, in addition to the above essential components, the thermosetting resin composition for forming the insulating protective film used in the present invention may further include a curing accelerator, a filler, and an additive, if necessary and desired. A thixotropic agent may be added. In particular, it is preferable to add fine rubber particles in order to further improve the bending resistance, and to further improve the adhesion to the base S such as an underlying copper circuit, polyimide, or polyester film, and the adhesive layer. For this purpose, it is preferable to add polyamide fine particles.

As the rubber fine particles, any resin particles having rubber properties such as acrylonitrile butadiene rubber, butadiene rubber, and acrylic rubber are subjected to a chemical cross-linking treatment so as to be insoluble and infusible in an organic solvent. For example, "XER-91" (manufactured by Nippon Synthetic Rubber Co., Ltd.), "Staphyloid AC3355", "Staphyloid AC3832" and "IM10 lj (taken by Takeda Pharmaceutical Co., Ltd.)," Paraloid EXL 2655 "and" Paraloid EXL2 602 "(all manufactured by Kureha Chemical Industry Co., Ltd.). The polyamide fine particles may be any of B-aliphatic polyamides such as nylon, aromatic polyamides such as “Kepler”, and fine particles of an amide-bonded resin such as polyamideimide having a particle size of 5 O ^ m or less. For example, "VENTOSINT 2700" (manufactured by Daicel Huls Co., Ltd.) or "SP500" (manufactured by Toray Industries, Inc.) can be used. A method for preparing a thermosetting resin composition or a thermosetting resin composition varnish by mixing the above resin components is as follows, for example.

First, to make it easier to mix each component, for example, when using a solid resin, make it dissolved in an organic solvent at an appropriate concentration of 2 Ow% or more, and in the case of a liquid resin, use it as it is. Alternatively, dilute it appropriately to make it easy to handle. Subsequently, these liquid materials are mixed, and further, rubber fine particles, polyamide »stalks, other inorganic and organic fillers, thixotropic agents, additives and the like are added, and roll kneading is performed. When the dispersion is sufficiently completed, the kneading is terminated, and a thermosetting resin composition is obtained. At this time, the powder components such as inorganic and organic fillers and thixotropic agents preferably have a particle size (including a secondary particle size) of 15111 or less when dispersed.

The flexible thermosetting resin composition film used in the present invention is obtained by forming a varnish of the thermosetting resin product obtained as described above into a film. The flexible thermosetting resin composition film used in the present invention has no tackiness at room temperature, is so-called tack-free, softens as the temperature rises, and cures when the temperature further rises. , Which exhibits a behavior of solidification. As long as it has such properties, even if it is formed into a film by volatilizing only the solvent of the varnish of the thermosetting resin composition, it is heated to some extent and reacted to a B stage.

(Semi-cured) A film may be used. Production of such films Those skilled in the art can easily set appropriate conditions for each type of composition. For example, a resin obtained by blocking “TP1002” (NCO-terminated polybutadiene, manufactured by Nippon Soda Co., Ltd.) with methylethylketoxime and “GQ100” (OH-terminated polybutadiene, Nippon Soda Co., Ltd.) A thermosetting resin composition consisting of: (a) a varnish using an appropriate solvent; applying this varnish to a release film (described later); Within a temperature range from 5 to: L: dried for about 0 minutes to form a film, which can be a film suitable for use in the present invention. In the case of the above thermosetting resin composition, if the film forming conditions are higher in temperature or longer than this range, the curing reaction of the thermosetting resin composition proceeds to some extent, so that Adhesion to wire plate (flexible circuit board) is poor. On the other hand, when the temperature is lower than this condition or for a shorter time, tack remains on the film surface, which impairs workability.

On the other hand, the normal product form of the flexible thermosetting resin composition film is usually a three-layer laminate in which a release film is laminated on both sides of the flexible thermosetting resin composition film. Is done. This release film mainly plays a role in preventing mechanical damage to the surface of the flexible thermosetting resin composition film, preventing foreign matter from being mixed in, and preventing deterioration in storage stability due to the influence of moisture, etc. A flexible thermosetting resin composition film is necessary to store the film, but it is also a film that can be used for punching and laser processing, and for filling the conductor steps at the time of lamination without gaps. The selection is also important because it affects the ability to follow the conductor steps.

Examples of the material of the release film include those obtained by applying a release agent such as a silicon-based resin to the surface of a plastic film such as a polyethylene terephthalate film, a polyethylene naphthalate film, or a polypropylene film. It is not limited to these. In addition, the thickness of these release films should be about 5 to 150〃m to reduce the workability of the film and conductor loss. Although it is preferable from the viewpoint of followability, a release film having a different material and a different thickness may be combined on each side of the three-layer laminate. However, the thickness of the release film is preferably in the range of 20 to 100 m. When a release film thinner than this thickness range is used, the elasticity of the entire film laminate when punching is used. Insufficiently, there is a problem that machining cannot be performed with high accuracy.Furthermore, too much pressure is applied to every corner of the circuit gap because the followability of the difference is too good. From the target size of the insulating protective film, a problem that the resin of the insulating protective film protrudes from the side easily occurs. On the other hand, when a release film thicker than this thickness range is used, it is less preferable because the followability of the difference between the leads is reduced and a problem that the resin of the insulating protective film is not embedded between the conductors easily occurs. Not specifically, such release films as "PET50X" (manufactured by Lintec Corporation), "38E-010KA" (manufactured by Fujimori Industries Co., Ltd.), Examples include, but are not limited to, “EMB LETPTH-50” (manufactured by Unitika Ltd.).

The film formation of the flexible thermosetting resin composition and the production of the three-layer laminate are specifically performed by uniformly applying a varnish of the thermosetting resin composition on the release film described above, It can be obtained by drying under appropriate conditions according to the type of the resin, and finally putting a release film on the dried resin film surface. Regarding the coating method, ヮ Any method can be used as long as it can apply the varnish to a uniform film thickness. For example, the method can be achieved by a method such as a bar coat. It is more preferable to use the production machine.

More specifically, the flexible thermosetting resin composition film used in the present invention is produced by the following method. That is, after preparing a varnish of a thermosetting resin composition in which a compound having an appropriate molecular weight and a functional group equivalent is combined as described above, this is released from the mold. The film is applied to a thickness of 100 to 100 ^ m, and then the solvent is dried and removed under a temperature condition that does not cause a curing reaction of the resin composition to tack-free. Obtained by covering. The thickness of the flexible thermosetting resin composition film thus obtained is adjusted in the range of 5 to 150 m, depending on the solid concentration of the varnish and the coating thickness, and further in the range of 100 to 100 m. It is preferably adjusted to. If the thickness is smaller than this range, the function as a protective film of the flexible circuit is not sufficient, and if the thickness is thicker, the flexibility is impaired. Causes a problem. The method for laminating the flexible thermosetting resin composition film obtained by the above method to a flexible wiring board (flexible circuit board) to form a flexible insulating protective film is based on a laminating condition using a vacuum laminator. Although it is suitable in terms of control, it can be performed by other bonding means such as a vacuum press. Examples of the vacuum laminator include those manufactured by Morton Co., Ltd. and Meiki Seisakusho

Co., Ltd. can be mentioned. The bonding conditions need to be performed at a temperature at which the film of the flexible thermosetting resin composition melts. After lamination, it is completely cured under appropriate conditions to complete the insulating protective film. Those skilled in the art can easily set the conditions for laminating by vacuum lamination overnight, etc., but the laminating temperature is usually 70 to 1 in the case of vacuum lamination overnight. 5 0 ^e C, it is possible to perform the bonding under pressure by a roll if necessary pneumatically 2 0 mmH g the following conditions. After the lamination, the resin composition can be cured at a temperature in the range of, for example, 120 to 170 ° C., for example, in the range of 10 minutes to 3 hours to form a flexible insulating protective film on the flexible circuit board. . For example, “TP100_2_i (OH-terminated polybutadiene, manufactured by Nippon Soda Co., Ltd.)) was blocked with methylethylketoxime, and“ GQ100 ”(OH-terminated polybutadiene) was used. Chen, Nippon Soda (Shares ) Manufactured by the company) is preferably bonded in a temperature range of 70 to 120 ° C, preferably in a range of 30 to 120 seconds. Become. After the lamination, curing is completed preferably in the range of 120 to 170 ° 0, preferably in the range of 10 minutes to 3 hours, whereby a flexible insulating protective film is formed on the flexible circuit board.

The film can be patterned before the flexible thermosetting resin composition film of the present invention is bonded to a flexible circuit board. For example, before laminating to a circuit board, laminating by a punching process or laser beam in a state of a three-layer laminate or with one of the release films peeled off according to the design pattern of the insulating protective film Flexible circuit A desired pattern can be formed according to the circuit.

In the case of the conventional Karay-ray film, a film is punched into a mold corresponding to the corresponding TAB or COF by punching, and the insulating protective film of the flexible circuit is formed by the process of laminating the films one by one. I was However, as a result of diligent studies by the present inventors, the half-cat process used in the production of seals for lapels and the like was used for processing resin composition films for flexible circuit boards, and punching was performed as necessary. By combining them, the resin composition film is processed into a desired shape, and a flexible circuit that includes the process of forming an insulating protective film using a resin film. Continuous production by real-real reels. I found that it would be possible.

This will be described with reference to a schematic diagram.When processing the film used for coating the flexible circuit board shown in FIG. 1, the inner pattern of the three-layer laminated film is processed as shown in FIGS. 2A and 2B. Is completely punched out by punching. The punched portion is a portion corresponding to a device hole of a TAB tape or a land for mounting a chip component of C0F, for example, in a flexible circuit. You. 3b, which is the outer pattern of the three-layer laminated film shown in FIGS. 3A and 3B, is obtained by half-cut processing without processing the lower layer release film and the upper layer release film and the middle layer shelf. A cut is made only in the composition layer. In addition, a Thomson blade, a die blade with a controlled punching depth, a rotary blade, and the like are used for the half-cart processing. Next, by peeling off the unnecessary film part c consisting of two layers, the release film and the resin composition layer, as shown in FIGS. 4A and 4B, the resin composition corresponding to the shape of the flexible circuit board is removed. You can create a film.

Further, as shown in FIG. 5, the resin film can be subjected to pattern processing according to the shape of the flexible circuit board as described above, and unnecessary edge portions can be continuously peeled off. The reason why the inner pattern is completely punched out by punching is that this portion cannot be continuously peeled because it does not connect to the outer portion.

Next, after releasing the release film remaining as the upper layer, the resin composition layer formed on the release film and processed according to the shape of the flexible circuit board is integrated with the flexible circuit Si board on the tape. Can be attached to When the release film remaining as the upper layer is peeled off, the release film is continuously peeled off by using a sticky roll or the like to continuously absorb the release film to the roll or the like. It is possible to

The insulating protective film can be formed on the flexible circuit by peeling off the release film from the bonded resin composition layer and then thermosetting. If the release film has a surface treatment or the like and can be peeled off after curing, it can be peeled off after thermal curing.

As described above, the introduction of a half-cart process for film processing enables continuous production of flexible circuits ai-reel by reel-to-reel, and is extremely excellent in production on an industrial scale. How to form an insulating protective film on a substrate A method or method of manufacture is provided.

The flexible thermosetting resin composition of the present invention described above is formed into a film, and the film is subjected to a film processing step including the above-described half-cutting step. As a result, the above-mentioned resin is prevented from flowing out, and a flexible insulating protective film excellent in various characteristics such as flexibility is continuously formed on the flexible circuit, thereby providing a flexible circuit excellent in various characteristics. Provided with high productivity on an industrial scale.

The tape-shaped flexible circuit board on which the insulating protective film is formed as described above is cut into individual circuits and used for various electronic devices.

(Brief description of drawings)

Figure 1 shows an example of a design pattern for film processing used for the coating of a flexible circuit.

FIG. 2A is a diagram showing an inner pattern a for punching the upper portion of the film. FIG. 2B is a diagram showing a cross section of the film of FIG. 2A as viewed from the side.

FIG. 3A is a diagram showing an outer pattern b for performing half-cut processing on the upper part of the film.

FIG. 3A is a cross-sectional view of the film of FIG.

FIG. 4 (d) is a view showing a film processed into the shape of a flexible circuit board after the film edge side c is peeled off.

FIG. 4B is a cross-sectional view of the film of FIG. 4A as viewed from the side.

FIG. 5 is a conceptual diagram of a process of continuously removing unnecessary film on the edge side after the half-cut processing.

FIG. 6 is a diagram showing a design pattern for film processing of Example 8. (Best mode for carrying out the invention)

Hereinafter, a production example of a compound that is a component of the flexible thermosetting resin composition film used in the present invention, and a production example of a flexible thermosetting resin composition film, and a comparison of examples of the present invention The present invention will be described more specifically with examples.

1. <Production example of component compounds>

Production Example 1: Preparation of resin varnish D

In the reaction vessel, "Byron 200" (OH-terminated polyester, Mn = about 15, 000, OH equivalent = 7, 01 g / eq., And solid content = 100w%: manufactured by Toyobo Co., Ltd.) 2,250 g and Ethyldiglycol Acetate (manufactured by Daicel Chemical Industries, Ltd.) 1,833 g, and “Ivsol 150” (manufactured by Idemitsu Petrochemical Co., Ltd.) 917 g, and 130. The mixture was stirred while being heated to C and dissolved to prepare a resin varnish (hereinafter referred to as a resin varnish D).

Properties of resin varnish D: Mn = about 15,000, OH equivalent (including solvent) = 15, 586 g / eq., And solids content = 45 w%.

Production Example 2: Preparation of tree B varnish E

50 g of “G-3000” (OH-terminated polybutadiene, Mn = about 3,000, OH equivalent = 1, 798 g / eq., And solid content = 100 w%: manufactured by Nippon Soda Co., Ltd.) 23.5 g of "Ivuzol 150" (manufactured by Idemitsu Petrochemical Co., Ltd.) and 0.007 g of dibutyltin laurate were added and mixed, and uniformly dissolved. 50 when uniform. The temperature was raised to C, and while stirring, 4.8 g of toluene-1,2,4-diisocyanate (NCO equivalent = 87.08 g / eq.) Was added, and the mixture was reacted for 2 to 4 hours. The reaction was then cooled to room temperature and 8.83 g of benzophenonetetracarboxylic dianhydride (acid anhydride equivalent 161.1) was added thereto. Then, 0.07 g of triethylenediamine and 74.09 g of triglyme were added, and the mixture was heated to 130 ° C. with stirring and reacted for 2 to 6 hours. When FT-IR (Fourier transform infrared spectroscopy) confirmed the disappearance of the 2,250 cm— ¹ NCO beak, toluene-1,2,4-diisocyanate (1 ^ €! 0 equivalent = 87.08 g) / eq.) 1.43 g was added, and again stirring was carried out at 130 ° C. for 2 to 6 hours, and the disappearance of NCO was confirmed by FT-IR. When the disappearance of NC0 was confirmed, it was regarded as the end point of the reaction, and the reaction mixture was cooled to room temperature and filtered with a 100-mesh filter cloth to obtain a modified polyimide resin varnish as a filtrate (hereinafter referred to as resin varnish E).

Properties of resin varnish E: Mn = about 25,000, acid anhydride equivalent (including solvent) = 14,708 g / eq., And solids content = 40 w%.

Production Example 3: Preparation of resin varnish F

In the reaction vessel, add “HTP-9” (NCO-terminated polybutadiene, NCO equivalent = 467 g / eq., And solids content = 100w%: manufactured by Idemitsu Petrochemical Co., Ltd.) 1,000, and ethyl diglycol acetate ( 216 g of Daicel Chemical Industries, Ltd.) and 0.1 g of dibutyltin dilaurate were added and mixed, and uniformly dissolved. When the temperature became uniform, the temperature was raised to 70 ° C, and with further stirring, 224 g of methylethylketoxime (molecular weight 87.12) was added dropwise over 2 hours. When the disappearance of the NC0 beak of 2,250 cnT ¹ was confirmed, the temperature was lowered to obtain a resin varnish (hereinafter, referred to as resin varnish F).

Properties of resin varnish F: Mn = about 12,000, NCO equivalent (including solvent) = 672.5 g / eq., And solids content = 85 w%.

Production Example 4: Preparation of resin varnish G

Reaction "G-3000" (OH-terminated polybutadiene, Mn = about 3,000, OH equivalent = 1,798 g / eq., And solid content-100w: Nippon Soda Co., Ltd. 50 g), 65.6 g of "Ivuzol 150" (manufactured by Idemitsu Petrochemical Co., Ltd.) and 0.007 g of dibutyltin laurate were mixed and uniformly dissolved. 50 when uniform. The temperature was raised to C, and while stirring, toluene-1,2,4-diisocyanate (] ^ (0 equivalent = 87.08 g / eq.) 3.0 § was added, and the reaction was carried out for 2 to 4 hours. When the temperature became uniform, 0.67 g of methylethyl ketoxime (molecular weight 87.12) was added dropwise over 2 hours with further stirring, and the mixture was kept for 1 hour. When the disappearance of the NCO peak at 2,250 cu ¹ was confirmed, the temperature was lowered to obtain a resin varnish (hereinafter referred to as “resin varnish G”) Properties of resin varnish G: Mn = about 15,000, NCO equivalent ( Solvent included) = 17,043 g / eq., And solids content = 45 w%.

2. Preparation of resin composition>

Resin component compounds Al, A2, A3, Bl, B2, and B3 are used as sales resins and varnishes prepared in Production Examples 1 to 3 above, as well as rubber fine particles and polyamide fine particles. A resin composition having the composition was prepared. In preparing these resin compositions, in addition to these resin components, dibutyltin dilaurate as a curing accelerator, "Aerosil 200" (manufactured by Nippon Aerosil Co., Ltd.) as an anti-sagging agent, and a viscosity modifier Carbitol acetate was added in an appropriate amount for each formulation, mixed, and kneaded with three rolls. The liquid ink fried as a comparative example was one using this resin composition (varnish) as it was, and the film was prepared using this resin composition by a method described later.

Specific compounding contents (compositions) are shown in Table 1 below as examples of the present invention, and in Table 2 below as comparative examples. Comparative Example 8 in Table 2 shows a 37.5〃m-thick sales Kanoi Ray Film “CVK0525KA” (manufactured by Arisawa Seisakusho Co., Ltd.). With these resin compositions, the basic properties as a general flexible circuit insulation protective film Characteristics, performed

Table 1

Lol Example 1 Example 2 Example 3 Example 4

GQ1000 20 8.9 20 20 13.3

A1 compound

A665 20

Resin varnish D 13.3 17.8 8.9 Compound

Resin varnish E 2.5

A3 compound! ^ PE555 2

B1 compound Resin varnish F I ^, £. O. 1 Π

B2 compound Resin varnish G

B3 compound S4265

Rubber particles 1 1

CO

C Polyamide fine particles. 1 1 Form Film Film Film Film Film Film

Average value of functional group equivalent of component A and component B 539g eq 484g eq 866g eq 568geq 570g eq 539geq 594g eq

Table 2

l

Comparative Example 1 Comparative 1> ¾ AAdJSn! L2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 ■ K School W, 8

GQ1000 2.2 20 20 13.3 CVK0525 A

A1 compound

A665

Resin varnish D 20 20 8 9 17.8 8.9

A2 compound

Resin varnish E 2.5

A3 compound PE555 1 ο 2

B1 compound Resin varnish F 1.Π Q 1

I U. Ό 1 O Q. * r

B2 compound Resin varnish G 56.2 56.2

B3 compound LS4265 30.3

Rubber particles 1 1

CO Polyamide fine particles 1 1

Form Film Film Film Liquid ink Liquid ink Liquid ink Liquid ink film

Average of functional group equivalents of A and B components 4232g eq 2253geq 254geq 563geq 597geq 539geq 687g eq

Notes on Tables 1 and 2

(a) GQ1000j (manufactured by Nippon Soda Co., Ltd.): OH-terminated polybutadiene, Mn = about 3.100, OH equivalent

S (including solvent) = 1, 122.2 g / eq., Solid content = 45 w%.

(b A665j (Sumitomo Bayer Urethane Co., Ltd.): acrylic polyol,

Μπ = about 1, 000, equivalent (including solvent) = 607 _g / _eq ., Solid content = 65 w% ₀

(c) Resin varnish D: Mn = about 15,000, OH equivalent (including solvent) = 15,586 g / eq.,

Solids = 45w%.

(d) Resin varnish E: Mn = about 25,000,

Acid anhydride equivalent (including solvent) -14, 708g / eq.

(θ) rpE555j (manufactured by Toho Chemical Co., Ltd.): EO-modified pentaerythritol,

Mn = 550, OH exposure-138 g eq., Solids content = 100 w%.

Oil varnish F: Mn = about 12,000, NCO equivalent (including solvent) = 672.5g / eq.,

Solids = 85w. .

(g) Resin varnish G: Mn = about 15,000, NCO equivalent (including solvent) = 17, 043 gZeq., solid content

= 45w%.

(h) l "LS4265 J (manufactured by Sumitomo Nouriel Perethane Co., Ltd.): oxime block of isophorone disocyanate trimer, Mn = about 1,000, NCO equivalent (including solvent) = 519 g eq.,

Solids = 65w%.

(i) rXER-91 "(manufactured by Nippon Synthetic Rubber Co., Ltd.): fine rubber particles.

(j) rVENTOSINT2070j (manufactured by Daicel Huels Co., Ltd.): Polyamide fine particles.

(k) The numerical values in the table indicate parts by weight including the solvent component in the raw materials.

(1) The average value of the functional group equivalents of the component A and the component B in the composition can be determined by the following equation.

That is, (average value of functional group equivalents of component A and component B) = ∑ ((parts by weight including solvent) X (ratio of solids)) ∑ ((parts by weight including solvent) Base equivalent)). Here, Γparts by weight J including the solvent, “the proportion of the solid content”, and “functional group equivalent including the solvent” refer to each compound of the component A and the component B in the composition.

(m) Regarding the molecular weight of each component specified in the present invention and the functional group equivalent of each component, in the case of this example and comparative example, the molecular weight is shown in the remarks column of Tables 1 and 2 (this remarks column). The corresponding functional group equivalent is described, and the functional group equivalent is obtained from the functional group equivalent including the solvent in this remarks column by the following formula: (functional group equivalent) = (functional group equivalent including solvent) ( Solids). 3. Making test specimens>

(a) Film production method:

“# 50X” (manufactured by Lintec Corporation, thickness 50 zm) was used as the release film. First, each of the various resin compositions shown in Tables 1 and 2 was coated on the release-treated surface of the release film so that the thickness of the coating film after drying was approximately 40 μm, and hot air was applied. It was dried at 70 ° C for 10 minutes in a drying oven. Subsequently, “PET 50X” was superimposed on the dried resin composition surface so that the release-treated surface was in contact therewith to form a three-layer film laminate. The first “: PET50X” was used as a support film (lower release film), and the last laminated “PET50X” was used as a cover film (upper release film).

(b) Preparation of test piece for evaluation of insulating protective film using film:

The cover film of the film laminate prepared by the above method is peeled off, and the test substrate specified for each evaluation item is laminated with a vacuum laminating device (batch type) (Morton Co., Ltd.). After the film was peeled off, it was cured in a hot-air drying oven at 150 ° C for 30 minutes to form a protective film. Bonding was performed at a temperature of 70 to 120 ° C; air pressure of 4 mmHg for 60 seconds. The temperature was set at the temperature at which the flow of the insulating protective film was smallest for each film, and each test piece was prepared.

(c) Preparation of test piece for evaluation of insulating protective film using liquid ink:

Coating is performed on the test substrate specified for each evaluation item so that the thickness of the coating film at the time of hardening becomes approximately 40 m, and 150 is applied in a hot air drying oven. C was cured for 30 minutes to form a protective film.

4. Method for evaluating coating film characteristics>

① Warp test

35 mm X 6 Ommx 7 polyimide film ("UPILEX S" )) Form a cured film using each film and liquid ink according to the preparation of the test piece above, so that the cured film has a size of 25 mm x 35 mm x 40 / m. The amount of warpage was measured. The measurement was made based on the floating amount at the center of the polyimide film in the arch shape seen when the protective film was placed down. 〇: The amount of warpage is 1 mm or less, and X: The amount of warpage is 1 mm or more.

②Bending resistance evaluation (spring back test)

A cured film using each film and liquid ink was formed on the Teflon plate according to the above-described test piece preparation method, and then the cured film was peeled off from the Teflon plate, and then 5 mmx4 Ommx40 m Cut to size. On the other hand, a scale was prepared, a flat plate was placed over a place 3 mm above the plate surface of the scale, and the flat plate was fixed so as not to move at this height. Furthermore, the test piece prepared in advance was sandwiched between the surface of the weighing dish and the flat plate while maintaining a state of being bent 180 degrees in a U-shape at the center. The weight indicated by the balance at this time was measured as a spring park value. 〇: less than 0.3 g, Δ: 0.3 or more to less than 1 and X: 1 g or more.

③Empi ヅ Hardness test

A protective film using each film and the liquid ink was formed on a copper plate, and the surface was evaluated by a pencil pull test. A protective film using each film and the liquid ink was formed on a comb having a conductor width of 0.318 mm, and the electric resistance one hour after boiling was measured.

薬品 Chemical resistance test

Each film and a protective film using a liquid ink were formed on a copper plate, and the surface was rubbed with a cloth impregnated with isopropanol to observe the appearance. 〇: No abnormality, and X paint film deterioration.

⑥Solder heat resistance test Form a protective film using each film and liquid ink on a copper plate, apply “Flux JS-64MS-S” on it, immerse it in a 260 ° C solder bath for 10 seconds, Observed. 〇 ··· No abnormality, △: Slight swelling occurred, and X: Remarkably deteriorated coating film.

⑦Adhesion test

A protective film using each film and liquid ink is formed on a copper plate and a polyimide film ("UPILEX Sj"), and the surface of this film is formed with 100 lmm squares along the cartridge guide.状態: 100/100, Δ: 90/100 or more, and X: 90/100 or less.

試験 Line flow rate test

Line / space = 25 m / 25 m Conductor wiring, copper foil / polyimide tape ¾ ^ (flexible circuit board), 0.9mx2 Ommx 40 m A protective film using a liquid ink was formed, and the amount of the flow of the protective film at the end due to capillary action was measured. The formation of the protective film followed the test piece preparation method before curing. In addition, curing was carried out with a gap of 3 mm provided and wound on a reel. 〇: less than 50 zm, △: more than 50 Aim and less than 100 ίπι, and X: more than 100 ^ m.

5. Results of coating film test>

The measurement results are shown in Tables 4 and 5 below.

Table 4

Lol SS example 1 Λ¾ example 2 example 3 example 5 SS example 6 Reversal o ο o ο 0 ο ο Flexural resistance o ο o ο ο ο ο umpty hardness 2H 3Η 3H 2Η Η 2Η 3Η

S stunning greenness (Ω) f 衆荣 1ϋ 荣 1ϋ 荣 ϋ 荣 Heat resistance Isopropanol o ο o ο. 0Ο ο Solderability o ο o ο ο ο ο

On polyimide o ο o ο ο ο ο Adhesion

鋇 Top o ο o ο ο ο ο Flow between lines (jum) o ο o ο 0 ο ο

Table 5

CO

CO

From the results of the above-mentioned coating film tests, it was found that the use of the flexible thermosetting resin composition film laminate of the present invention allows bleeding (flowing out) between conductors and wirings while maintaining the characteristics of the conventional liquid urethane resin composition. Volume) can be significantly reduced. In addition, it was confirmed that the film was more flexible than the current cover film. Example 8

The same resin composition film (three-layer laminate) as in Example 7, which was manufactured by the above-described pattern preparation of the shape shown in FIG. Using a punching machine for labels, the outer pattern was cut into two layers by half-cutting, and the inner pattern was punched out by punching. The half-cut edge portion was peeled off to produce a resin composition film tape in which the shape shown in FIG. 6 was continuously repeated.

Line / space = 25 / uL m / 25 Laminate the resin composition film tape on lmx 35 mm copper foil / polyimide tape (flexible circuit board tape) with 25 m conductor wiring using a vacuum laminator Was. The laminating conditions were a vacuum laminator (roll type) manufactured by Hitachi Industries, Ltd. at a temperature of 100 ° C, an air pressure of ImmHg or less, and a transfer speed of lmZ minutes. Subsequently, after the release film was peeled off, the film was cured in a hot air drying oven at 150 ° C. for 30 minutes to form an insulating protective film.

As a result of performing various tests in the above (1) to (4) on the flexible circuit having the insulating protective film formed in this way, the same results as shown in Table 4 were obtained.

⁽ Industrial applicability) According to the method of forming a thermosetting resin composition as defined in the present invention into a film and bonding the same under appropriate conditions to form an insulating protective film of a flexible circuit fiber, it cannot be achieved with the liquid resin composition ink. The flow rate of the resin composition can be suppressed to a level. That is, a thermosetting resin composition composed of components defined by the molecular weight and the functional group equivalent is formed into a film under the condition that the stiffening is not completed, and the film is laminated to a circuit board, so that the width between conductors is 30 mm. m, the flow of the resin composition is suppressed to 50 m or less, and a highly flexible insulating protective film can be formed. In addition, since the flexible insulating protective film is excellent in chemical resistance, flexibility, impact resistance, adhesion, electrical insulation, and the like, the present invention provides a fine pitch that requires a finer circuit design. It is particularly useful as a method for forming a flexible insulating protective film opposite to a flexible circuit.

Claims

The scope of the claims

1. At least one compound (component A) selected from the group consisting of Al, A2 and A3 below and at least one compound (component B) selected from the group consisting of Bl, B2 and B3 below A thermosetting resin composition containing the component A compound and the component B compound and having an average functional group equivalent 嫜 of 300 to: I, 200 g / eq. Forming a flexible thermosetting resin composition film through a varnish, and laminating the flexible thermosetting resin composition film to a flexible circuit board.

A 2: a compound having a number average molecular weight of 13,000 to 30,000 and a functional group equivalent of 1,300 to 1,500 Og / eq.

A3: a compound having a number average molecular weight of 200 to: L, 200 and a functional group equivalent in the range of 20 to 400 g / eq.

B 1: Compound having a number-average molecular weight of 1,000 to 8,000, a functional group capable of reacting with any of Compounds A1 to A3, and a functional group equivalent of 100 to 4,000 g / eq. ,

B 2: having a number average molecular weight of 13,000 to 30,000 and having a functional group capable of reacting with any of the compounds A1 to A3, and having a functional group equivalent of 1,300 to 15,000 g / eq.

B3: A compound having a number average molecular weight of 200 to 1,200, a functional group capable of reacting with any of Compounds A1 to A3, and a functional group equivalent of 20 to 400 g / eq.

2. The flexible insulation of flexible circuit fibers according to claim 1, characterized in that the average of the functional group equivalents of the A component compound and the B component compound is 500 to 1, OOO gZe q. Film formation method.

3. The thermosetting resin composition comprises at least one compound selected from A1 as the A component compound, and at least one compound D selected from B1 as the B component compound. 3. The method for forming a flexible insulating protective film of a flexible circuit board according to 1 or 2.

4. The thermosetting resin composition contains at least one compound selected from A1 and at least one compound selected from A2 as the A component compound, and at least one compound selected from B1 as the B component compound. The method for forming a flexible insulating protective film on a flexible circuit board according to claim 1 or 2, wherein the method comprises:

5. The thermosetting resin composition contains at least one compound selected from A2 and at least one compound selected from A3 as the A component compound, and at least one compound selected from B1 as the B component compound The method for forming a flexible insulating protective film of a flexible circuit according to claim 1 or 2, wherein:

6. All or at least one of the A component compound and the B component compound contained in the thermosetting resin composition has a polybutadiene skeleton, a hydrogenated polybutadiene skeleton, a polysiloxane skeleton, a polyethylene glycol skeleton, a polypropylene skeleton, and a polyisoprene skeleton. The flexible circuit according to any one of claims 1 to 5, wherein the compound has at least one skeleton selected from the group consisting of:

7. In the functional group of the component A compound and the component B contained in the thermosetting resin composition, one of the component A and the component B is hydroxyl. The method for forming a flexible insulating protective film of a flexible circuit board according to any one of claims 1 to 6, wherein the compound has a group and the other is a compound having a procysocyanate group.

8. The flexible circuit according to any one of claims 1 to 7, wherein the A component compound and the Z or B component compound contained in the thermosetting resin composition include at least a polyester resin. Method for forming protective film.

9. As a component A compound and / or a component B compound contained in the thermosetting resin composition, a bifunctional hydroxyl group-terminated polybutene having a number average molecular weight of 800 to 5,000, the following general formula (1) )) And a modified polyimide resin represented by the following general formula (3) obtained by reacting three kinds of compounds of a diisocyanate compound represented by the following general formula (2): 6. The method for forming a flexible insulating protective film of a flexible circuit according to any one of claims 1 to 5, wherein the method comprises:

(1)

(R1 represents a residue obtained by removing the carboxyl group from an organic compound having four carboxyl groups.)

0CN 2—— NC0)

(3)

(R1 is a residue obtained by removing the carboxyl group from an organic compound having four carboxyl groups, R2 is a residue obtained by removing the isocyanate group from an organic compound having two isocyanate groups, and R3 is a hydroxyl-terminated polybutadiene. X and y represent the constituent ratios of polybutadiene units and polyimide units, respectively, and η represents the degree of polymerization, where x + y = 1, 0 x 1, 0 and 1 and 1≤n≤10,000.)

10. The ratio of the component A compound to the component B compound in the thermosetting resin composition in terms of the number of functional group equivalents is from 1/3 to 3-1/3 to 3. 10. The method for forming a flexible insulating protective film for a flexible circuit according to any one of 9.

11. The flexible insulating protective film formation of the flexible circuit according to any one of claims 1 to 10, wherein the thermosetting resin composition also contains rubber-like fine particles and Z or polyamide fine particles. Method.

12 2. After the thermosetting resin composition is formed into a film, the desired pattern is created by punching or laser processing the film according to the design pattern of the insulating protective film, and then applied to the flexible circuit board. The flexible circuit according to any one of claims 1 to 3, characterized in that the flexible insulating protective film is formed opposite to the flexible circuit.

13. The flexible thermosetting resin composition film having a three-layer structure of a release film / flexible curable resin composition layer Z release film, according to any one of claims 1 to 12, wherein Flexible circuit described ¾ Flexible insulation protection MB formation method.

14. A method for manufacturing a flexible circuit board having a flexible insulating protective film formed thereon, the method comprising forming a flexible insulating protective film by the method according to any one of claims 1 to 13.

15. A flexible circuit having a flexible insulating protective film formed by the method according to any one of claims 1 to 13. »¾

16. A flexible circuit fiber having a flexible insulating protective film formed by the method according to claim 14.

17. A flexible thermosetting resin composition film having a three-layer structure of release film / flexible curable resin composition layer / release film

(1) A half-cut that cuts into the release curable resin composition layer Process, and

② Punching process for punching 3 layers if necessary, and

(3) A step of peeling the edge of the flexible thermosetting resin composition film according to the cut in the half-cart process

Forming a desired pattern on a flexible curable resin composition film by using the method described above, and attaching the desired pattern to a flexible circuit board.

18. A method of manufacturing a flexible circuit board having a flexible insulating protective film formed thereon, wherein the flexible insulating protective film is formed by the method according to claim 17.

19. A flexible circuit, wherein a flexible insulating protective film is formed by the method according to claim 17.

20. A flexible circuit scythe on which a flexible insulating protective film is formed, which is manufactured by the manufacturing method according to claim 18.

21. The method according to claim 13, wherein the flexible thermosetting resin composition film is

(1) a half-cut process for making a cut in the release film / flexible curable resin composition layer, and

② Punching process for punching 3 layers if necessary, and

Forming a desired pattern on a flexible curable resin composition film by using the above method, and laminating the desired pattern on a flexible circuit fiber.

22. Forming a flexible insulating protective film by the method described in claim 21. Method for manufacturing flexible circuit scythe having flexible insulating protective film formed thereon

23. A flexible circuit in which a flexible insulating protective film is formed by the method according to claim 21.

23. A flexible circuit board, comprising a flexible insulating protective film produced by the production method according to claim 22.