JPH05154975A - Manufacture of polyimide laminate - Google Patents

Abstract

PURPOSE:To improve productivity and yield of a laminate having an opening part easily at a low cost under moderate working conditions by a method wherein a polyamic acid prepreg having an opening part is thermally fixed by pressure to a conductive foil. CONSTITUTION:As conditions for superimposing a specific number of polyamic acid films to be thermally fixed by pressure to a conductive foil, 70-200 deg.C, 5-100kg/cm<2>, 5-30min for a press type laminator and 70-200 deg.C, 1-50kg/cm<2>, 0.1-10m/min for a roll type are suitable. Especially for the temperature, execution at a temperature 10-30 deg.C lower than a drying temperature of polyamic acid is preferable because of no occurrence of volatile matter. A rate of forming imide under a polyamic acid prepreg condition is 10-50%, preferably 20-40%. Metallic foils of copper, aluminum, constantan, nickel, etc., are exemplified as the conductive foil.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a polyimide laminated board.

[0002]

2. Description of the Related Art Linear polyimides are excellent in heat resistance, chemical resistance, electrical characteristics, etc., but generally have very poor moldability, and it has been difficult to form a laminated board of linear polyimides. In recent years, using a thermoplastic polyimide, a method of melt-molding at high temperature and high pressure has been proposed, but since it must be molded at 300 ° C. or higher, it is not possible to apply a conventional apparatus, and as a polyimide Since it is unavoidable to use a thermoplastic resin having inferior heat resistance, it was not possible to obtain a laminate of high heat resistant polyimide resins such as Kapton (made by DuPont) and Upilex S (made by Ube Industries).

[0003]

The object of the present invention is to obtain the folding resistance, alkali resistance, solvent resistance and heat resistance of the high heat resistant linear polyimide, which cannot be realized by the conventional melt molding method. , A polyimide laminate having electrical and mechanical properties.

[0004]

According to the present invention, a polyamic acid capable of forming a linear polyimide is applied to and impregnated in a heat-resistant fiber base material, and then the obtained prepreg is subjected to predetermined perforation as necessary. After that, it is heated and pressure-bonded with the conductor foil to imidize, and the method for producing a linear polyimide laminated plate is characterized.

That is, the polyamic acid prepreg containing the heat-resistant fiber base material is applied by coating or dipping the polyamic acid solution on the heat-resistant fiber base material made of woven or non-woven fabric such as glass fiber, carbon fiber or aramid fiber. -It can be obtained by impregnating and then drying until tack-free. Alternatively, a polyamic acid prepreg with a release film may be prepared by stacking a heat-resistant fiber base material on a release film, applying a polyamic acid solution, and drying it until a tack-free state is obtained. Furthermore, a polyamic acid prepreg is prepared by a conventional method, for example,
The holes are formed by punching, cutting or the like.

The polyamic acid prepreg, which has been subjected to the hole processing, can be made into a linear polyimide laminate having an opening by heating and press-bonding the conductor foil and then sufficiently imidizing it.

In the present invention, suitable conditions for forming the polyamic acid prepreg by drying the polyamic acid solution are 80 to 200 ° C. and 5 to 30 minutes. When the temperature is lower than this and the time is short, the volumetric shrinkage due to the evaporation and imidization of the solvent after that is severe, and when it is used as a laminated board, when it is heated and pressure-bonded to the conductor foil, the fluidity is large and the open part Bleeding and bleeding are large, the variation in film thickness is large, and the dimensional change after imidization is large.
If the temperature is higher and the time is longer than this, the fluidity is too small and the peel strength between the conductor foil and the conductor foil decreases when the conductor foil is heated and pressure-bonded, and voids increase.

The conditions for heating a predetermined number of polyamic acid films and heating and pressure-bonding with the conductor foil are: 70 to 200 ° C., 5 to 100 kg / cm ² , 5 to 30 minutes for the press type, and 5 to 30 minutes for the roll type laminator. 70-200 ℃, 1-50kg / cm, 0.1-1
The condition of 0 m / min is suitable, and it is preferable that the temperature is lower than the drying temperature of the polyamic acid by 10 to 30 ° C., since no volatile matter is generated.

The imidation ratio of the polyamic acid prepreg is preferably 10 to 50%, and preferably 20 to 40%. If the imidization ratio is less than 10%, not only does tackiness remain and workability is poor, but it also becomes difficult to isolate the films one by one by adhering them to the release film.
When imidization is performed as described above, the melting characteristics deteriorate and molding becomes difficult.

The polyamic acid in the present invention is usually obtained by reacting a diamine with an acid anhydride.
Examples of the diamine include phenylenediamine, diaminodiphenylmethane, diaminodiphenyl sulfone, and diaminodiphenyl ether, and examples of the acid anhydride include trimellitic anhydride, pyromellitic dianhydride, biphenyltetracarboxylic dianhydride, and benzophenonetetracarboxylic acid. It is possible to use dianhydride and the like, one for each
One kind or two or more kinds can be appropriately combined and used.

Materials that can be used as the conductor foil include metal foils such as copper, aluminum, constantan and nickel.

Materials usable as the heat resistant fiber base material include glass fiber, carbon fiber, aramid fiber,
Examples thereof include woven fabrics and non-woven fabrics in which any one kind or a combination of two or more kinds such as potassium titanate fibers is used.

Materials that can be used as the release film include plastic films such as polypropylene, polyester, polyether sulfone, polyimide and polyethylene.

[0014]

The present invention relates to a method for producing a linear polyimide laminate, wherein a polyamic acid prepreg having an opening portion is thermocompression-bonded to a conductor foil if necessary, so that the lamination sheet having an opening portion can be made mild. It can be easily and inexpensively obtained under processing conditions with high productivity and yield.

[0015]

【Example】

(Example 1) 108 g of purified anhydrous paraphenylenediamine was placed in a 4-neck separable flask equipped with a thermometer, a stirrer, a reflux condenser, and a dry nitrogen gas inlet, and anhydrous N-methyl- A mixed solvent of 90% by weight of 2-pyrrolidone and 10% by weight of toluene was added and dissolved in an amount such that the solid content ratio in all the charged raw materials was 20% by weight. Dry nitrogen gas was allowed to flow in all steps from the reaction preparation stage to the product removal. Then purified anhydrous 3,
Although 294 g of 3 ', 4,4'-biphenyltetracarboxylic dianhydride was added little by little while stirring, since it was an exothermic reaction, cold water of about 15 ° C was circulated in the external water tank to cool it. After the addition, the internal temperature was set to 20 ° C. and the reaction was terminated by stirring for 5 hours to obtain a polyamic acid solution.

A commercially available glass fiber woven fabric was coated and impregnated with this polyamic acid solution using a bar coater, and the temperature was kept at 110 ° C. for 15 minutes.
Minute drying was performed to obtain a polyamic acid prepreg. The prepreg was superposed on a roughened surface of a commercially available copper foil, and heated and pressure-bonded with a press at 90 ° C., 40 kg / cm ² , and 15 minutes.
After that, heating was performed at 380 ° C. for 1 hour to complete imidization to obtain a copper-clad laminate.

Example 2 200 g of purified anhydrous 4,4'-diaminodiphenyl ether was placed in a 4-neck separable flask equipped with a thermometer, a stirrer, a reflux condenser and a dry nitrogen gas inlet. Anhydrous N-methyl-2-
A mixed solvent of 90% by weight of pyrrolidone and 10% by weight of toluene,
The amount of solid content in all the charged raw materials was 20% by weight, and the amount was dissolved. Dry nitrogen gas was allowed to flow in all steps from the reaction preparation stage to the product removal. Next, 218 g of purified anhydrous pyromellitic dianhydride is added little by little with stirring, but since it is an exothermic reaction,
This was cooled by circulating cold water of about 15 ° C in an external water tank.
After the addition, the internal temperature was set to 20 ° C., the mixture was stirred for 5 hours, the reaction was terminated, and a polyamic acid solution was obtained.

A carbon fiber cloth is placed on a commercially available polyester film, and this polyamic acid solution is applied and impregnated,
It was dried at 110 ° C for 15 minutes to obtain a polyamic acid prepreg with a release film. Next, with the polyamic acid side inside, sandwich the carbon fiber cloth between two sheets of polyamic acid prepreg with this release film, and use a roll type laminator at 90 ° C, 15 kg / cm ² , 0.2 m / Min., Heating / press bonding, then punching using a mold, peeling off the release film on one side, overlaying a polyamic acid prepreg surface on a commercial copper foil roughened surface, and using a press hand
90 degreeC, 40 kg / cm < ² >, 15 minutes heating-pressing was performed. afterwards,
The release film was peeled off and heated at 380 ° C. for 1 hour to complete imidization to obtain a copper-clad laminate.

(Example 3) Example 1 between release films
Sandwich two sheets of polyamic acid prepreg of, and press and heat at 100 ℃, 25kg / cm ² for 30 minutes,
The release film was peeled off, commercialized copper foil roughened surfaces were overlapped on both sides, and heating / press bonding was performed using a press at 90 ° C., 40 kg / cm ² , and 15 minutes. After that, peel off the release film, 1 at 380 ℃
It was heated for a period of time to complete imidization to obtain a double-sided copper-clad laminate.

[0020]

By using the manufacturing method of the present invention,
It was possible to obtain a copper-clad laminate having holes in the supporting insulating layer as required, and it was possible to obtain excellent polyimide properties even after completion of imidization. Furthermore, the production method of the present invention can be formed under mild conditions, and can be easily applied to a continuous process of a polyimide copper-clad laminate using a continuous sheet. It is suitable as a method for producing a prepreg for a polyimide laminate.

Claims (2)

[Claims] 1. A wire characterized in that a polyamic acid capable of forming a linear polyimide is applied and impregnated on a heat-resistant fiber base material, and then the obtained prepreg and a conductor foil are heated and pressure-bonded, and then imidized. Of manufacturing a strip-shaped polyimide laminate. 2. After performing a predetermined hole processing on the prepreg,
The method for producing a linear polyimide laminate according to claim 1, wherein the conductor polyimide is heated and pressure-bonded.