JPH0776024A - Manufacture of polyimide resin film - Google Patents

Abstract

PURPOSE:To obtain a manufacture of a polyimide resin film using a polyamide resin (high-rigidity polyamide resin) to which a manufacture of a resin film using a usual 'heated rotary drum' can not be applied because of its high rigidity. CONSTITUTION:A resin film is obtained by applying a high-rigidity polyamide resin before setting on the surface of a soluble support, and this film is made a polyimide resin film by subjecting it to heat treatment together with the support. Then, the polyimide resin film is separated singly by removing the support by dissolution. By this method, the resin of high rigidity can be made the film very easily. Therefore, the resin film having more excellent electrical and mechanical characteristics than usual can be prepared by using the method of this invention.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a method for producing a polyimide resin film, which is not applicable to the conventional method for producing a resin film using a "heated rotary drum" because of its high rigidity. It is referred to as a "rigid polyamide resin").

[0002]

2. Description of the Related Art A polyimide resin film, which is widely used as an insulating material for electronic parts because of its excellent electrical insulation, thermal properties and mechanical properties, is manufactured by coating a heated rotating drum with a polyamide resin and keeping the temperature below 150 ° C. It is dried at a temperature of 30 to 90 minutes to form a self-supporting film, which is then peeled off from the rotating drum, then gradually heated from 100 ° C. to 500 ° C. Is common.

Examples of the film processed in this manner include pyromellitic dianhydride and 4,4'-diaminodiphenyl ether as raw materials (trade name, manufactured by Kapton DuPont), 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride and p-phenylenediamine as raw materials (trade name Upilex s Ube Industries, Ltd.) pyromellitic dianhydride, 4,4'-diaminodiphenyl ether and p- A product made of phenylenediamine as a raw material (trade name NPI manufactured by Kanegafuchi Chemical Industry Co., Ltd.) is known.

Such a polyimide resin film is often used as an insulating material for electronic parts such as flexible printed circuit (FPC) boards and tape automatic bonding (TAB) tapes.

In recent years, there has been an increasing demand for high integration in electronic parts, and in order to meet this demand, a polyimide resin film having higher dimensional stability and low hygroscopicity and less interaction with a metal which is a circuit material is demanded. Various attempts have been made to develop it. However, a polyimide resin satisfying such requirements is usually obtained by heating a high-rigidity polyamide resin, and the continuous film forming method as described above cannot be adopted. Also, sacrificing productivity, applying a high rigidity polyamide resin on a wide flat plate, drying,
Even if it is baked, the film is broken when it is peeled from the flat plate. Therefore, a polyimide resin film that can be used for electronic materials has not been obtained.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object thereof is to provide a means for obtaining a polyimide resin film using a high-rigidity polyamide resin which has been difficult to form into a film. And

[0007]

As a result of various investigations to solve the above problems, the present inventors have found that a polyamide resin before curing is applied on a support and completely cured, and then the support is removed. The present invention has been completed by finding that a film can be formed by dissolving and removing the body. That is, the method of the present invention for solving the above-mentioned problems is to obtain a resin film by applying a high-rigidity polyamide resin before curing onto a soluble support surface, and heat-treating this with a support to form a polyimide resin film, Then, the support is dissolved and removed to isolate the polyimide resin film, preferably a high-rigidity polyamide resin using pyromellitic dianhydride and p-phenylenediamine as raw materials, or 3, 3, 4 , 4 '
-A benzophenone tetracarboxylic acid or 4,4'-diaminodiphenyl ether is used as a raw material. The support applicable to the present invention must be such that it does not deform during heat curing and can be dissolved and removed without affecting the formed polyimide resin film. From this point, it is preferable to use a metal foil as the support.

[0008]

The gist of the present invention is that a polyamide resin obtained by mixing a polyamic acid, a curing agent and a catalyst is applied onto a soluble support to form a resin film, which is cured as it is, then heat-treated, This is intended to obtain a polyimide resin film by dissolving and removing the support, and if attention is paid only to this point, the method of the present invention can be applied to the film formation of any synthetic resin material. However, the effect of the present invention can be exhibited for the first time by applying the method of the present invention to the production of a polyimide resin film using a high-rigidity polyamide resin to which the method using the conventional "heated rotating drum" cannot be applied. is there.

The high-rigidity polyamide resin to which the present invention is applied is (1) a polyamic acid prepared from pyromellitic dianhydride and p-phenylenediamine (2) 3,3,4,4'-benzophenone It is obtained by adding a curing agent or a catalyst to a polyamic acid or the like made from tetracarboxylic acid anhydride and 4,4′-diaminodiphenyl ether as raw materials.

As the curing agent and catalyst to be mixed with the polyamic acid, those which are generally used are used under general use conditions. Examples of the curing agent include acetic anhydride, phthalic anhydride,
For example, chloroacetic acid. Examples of the catalyst include pyridine, picoline, isoquinoline, triethylamine and the like.

The polyamide resin film thus obtained is heat treated together with the support. This heat treatment changes the polyamide resin film into a polyimide resin film. After the heat treatment, the support is dissolved and the polyimide resin film is separated. Therefore, it is necessary to use, as the support, one which is not deformed during the heat treatment and can be dissolved without affecting the polyimide resin film. From this point, it is preferable to use a foil of copper, nickel, iron, aluminum, zinc, cobalt or the like as the support.

[0012]

EXAMPLES Next, examples of the present invention will be described. (Example 1) 220 mol of 1 mol of pyromellitic dianhydride
It was dissolved in 0 g of N, N′-dimethylformamide and the resulting solution was cooled to 0 ° C. 1 mol of p-phenylenediamine was added to this solution at 0 ° C with stirring to obtain a polyamic acid. Acetic anhydride as a curing agent and pyridine as a catalyst were added to this polyamic acid, and they were sufficiently stirred and mixed. This mixture was applied on a surface of a copper foil having a thickness of 18 μm, a width of 500 mm and a length of 10 m using a knife coater so as to have a uniform thickness. This is 100,150,200,25
10 at each temperature of 0, 300, 350, 400, 450
It was held for a minute, and a heat treatment pattern in which the temperature rising rate between the temperatures was 5 ° C./minute was applied, and after the treatment, the temperature was allowed to cool to room temperature.

Next, the obtained heat-treated product was dipped in a ferric chloride solution having a concentration of 200 g / liter to completely dissolve the copper foil, thus obtaining a target polyimide resin. The obtained polyimide film had high insulation, low hygroscopicity, and high dimensional stability. Further, despite the heat treatment, no copper diffusion into the polyimide resin film was observed.

(Example 2) 3,3,4,4'-benzophenone tetracarboxylic acid anhydride was used in place of pyromellitic dianhydride, and 4,4'-diaminodiphenyl ether was used in place of p-phenylenediamine. A polyimide film was obtained in the same manner as in Example 1 except that the polyimide film was used. The obtained polyimide film had high insulation, low hygroscopicity, and high dimensional stability, similar to the one obtained in Example 1. Further, no copper diffusion was observed on the surface of the polyimide resin film.

Comparative Example 1 The same curing agent and catalyst as in Example 1 were added to the polyamic acid obtained in the same manner as in Example 1 and mixed to obtain a mixture. This mixture was applied to a rotating drum according to the conventional method and dried at 110 ° C. for 2 hours,
A self-supporting polyamide resin film was obtained. When this resin film was peeled off from the rotary drum, cracks were generated everywhere in the resin film, and the resin film was broken, so it was not possible to obtain a polyimide film by heat treatment.

Comparative Example 2 To the polyamic acid obtained in the same manner as in Example 2, a curing agent and a catalyst were added and mixed in the same manner as in Example 2 to obtain a mixture. This mixture was applied to a rotating drum according to the conventional method and dried at 110 ° C. for 2 hours,
A self-supporting polyamide resin film was obtained. When this resin film was peeled off from the rotary drum, cracks were generated everywhere in the resin film as in Comparative Example 1 and the resin film was broken, so that it was not possible to obtain a polyimide film by heat treatment.

(Comparative Example 3) A conventional polyamic acid was obtained from pyromellitic dianhydride and 4,4'-diaminone diphenyl ether as raw materials. Example 1 was used except that this was used.
A polyimide resin film was obtained in the same manner as in. Although the obtained polyimide resin film had hygroscopicity and dimensional stability comparable to those of the conventional product, the insulating property was somewhat poor, and diffusion of copper into the polyimide resin film was observed.

[0018]

According to the method of the present invention, a highly rigid resin can be formed into a film very easily. Therefore, by using the method of the present invention, it is possible to prepare a resin film having more excellent electrical and mechanical properties than ever before.

Claims (4)

[Claims] 1. A resin film is obtained by applying a high-rigidity polyamide resin before curing onto a surface of a support that can be dissolved, and heat-treating the resin film together with the support to obtain a polyimide resin film,
Then, the support is dissolved and removed to isolate the polyimide resin film, which is a method for producing a polyimide resin film. 2. The method for producing a polyimide resin film according to claim 1, wherein the raw materials of the highly rigid polyamide resin are pyromellitic dianhydride and p-phenylenediamine. 3. The raw material of the high rigidity polyamide resin is 3,
A method for producing a polyimide resin film, which comprises 3,4,4'-benzophenone tetracarboxylic acid anhydride and 4,4'-diaminodiphenyl ether. 4. The substrate is one kind of foil selected from the group consisting of copper, nickel, iron, aluminum, zinc, cobalt, and alloys thereof.
3. The method for producing a polyimide resin film according to any one of 3 above.