JPH0557802A - Manufacture of resin impregnated base material - Google Patents

Abstract

PURPOSE:To eliminate the generation of unimpregnated sections and improve resistance to heat, resistance to insulation and resistance to moisture absorption of a laminate sheet, a printed wiring board and the like by impregnating resin 9 a base material, drying, cooling a resin impregnated base material and then pressurizing and redrying the same. CONSTITUTION:Inorganic fiber such as glass, organic fiber such as polyester, polyamide or others, on a natural fiber such as cotton, paper or others is used as a base material, and said base material is impregnated in a manner of forming 50% resin amount, for example, 50% resin amount after being dried in phenol resin varnish. Then the base material is heat dried in a drying oven, and then cooled in a cool air cooling bath, and pressurized by passing through a pressurizing roll forming a couple of roll clearances. Then the base material is transferred again to the drying oven and heat dried. The base material is cut into the required dimension after being cooled to manufacture a resin impregnated base material. The generation of unimpregnated sections is eliminated by said process, and its resistance to heat, resistance to insulation and the like can be improved in the case of being used as an electric laminate, a printed wiring board and the like.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to electronic equipment, electric equipment,
The present invention relates to a method for producing a resin-impregnated base material used for electrical laminates, printed wiring boards and the like used in computing equipment, communication equipment and the like.

[0002]

2. Description of the Related Art Conventionally, a resin-impregnated base material used for electrical laminates, printed wiring boards, etc. is a long base material such as paper or glass cloth impregnated with resin, and the resin impregnation amount is set in a clearance such as a squeeze roll. However, it is difficult to evenly impregnate the base material with the resin, and if there is a non-impregnated part, it may cause a non-impregnated part. Heat resistance, insulation of wiring board,
It has been a factor that reduces the moisture absorption resistance.

[0003]

As described in the prior art, in the conventional resin-impregnated base material, unimpregnated portions are apt to occur, and the heat resistance, the insulation property of the electrical laminate and the printed wiring board,
It has been a factor that reduces the moisture absorption resistance. The present invention has been made in view of the above problems in the conventional art,
An object of the invention is to provide a method for producing a resin-impregnated base material in which no unimpregnated portion is generated.

[0004]

According to the present invention, a base material is impregnated with a resin and then sent to a drying step. During the drying step, the resin-impregnated base material is temporarily cooled, pressurized and then dried again. Since the method for producing a resin-impregnated base material is characterized in that the above-mentioned object can be achieved, the present invention will be described in detail below.

The base material of the resin-impregnated base material used in the present invention includes inorganic fibers such as glass and asbestos, organic fibers such as polyester, polyamide, polyacryl, polyvinyl alcohol, polyimide and fluororesin, and natural fibers such as cotton. Woven fabric, non-woven fabric, mat, paper, etc. Resins such as phenol, epoxy, unsaturated polyester resin, polyimide, fluororesin, and polyphenylene oxide are used as the resin with which the base material is impregnated, and if necessary, talc, clay, silica, calcium carbonate, aluminum hydroxide. Inorganic powder fillers such as can be added. The resin may be impregnated into the substrate regardless of whether it is impregnated on the entire surface or impregnated on one surface. Furthermore, the resin impregnation amount is 40 after drying.
It is preferably ˜60% by weight (hereinafter referred to simply as “%”). The amount of resin can be adjusted with a squeeze roll or the like. A heating furnace such as hot air, infrared irradiation or the like is used for the drying step, which is optional, but at least the drying step must be divided into two or more steps. Temporary cooling during the drying step is preferably performed in a cooling tank such as cold air, and is preferably cooled to 30 to 60 ° C. A roll or the like is used for pressurization at the time of temporary cooling, and a pair or a plurality of pairs are used as needed, but there is no particular limitation. Just cooling during the drying process,
It is preferable that the pressure is applied to the uncured state of the resin-impregnated base material in the first half of the entire drying process.

The present invention will be described below based on examples.

[0007]

Example: A resin amount of kraft paper of 116 g / m ² is 50%.
The phenol resin varnish of No. 1 was impregnated so that the amount of resin after drying was 50%, heated in a drying oven at 155 ° C. for 5 minutes, cooled in a cool air cooling tank at 50 ° C., and then paired with a pair of rolls. After pressing through a pressure roll having a clearance of 100 microns, it was sent to a drying furnace at 155 ° C., heated at 155 ° C. for 15 minutes, cooled, and then cut into a required size to obtain a resin-impregnated base material. Next, the thickness of 0.018 m was applied to the upper surfaces of the eight resin-impregnated base materials.
A copper foil with an adhesive of m was placed with the adhesive side inside, and a laminate was formed at a forming pressure of 100 Kg / cm ² and 160 ° C.
It was heated and pressed for 0 minutes to obtain a laminated plate having a thickness of 1.6 mm.

[0008]

[Comparative Example 1] A resin-impregnated base material was obtained in the same manner as in Example 1 except that a cooling tank and a pressure roll were not used.
A 6 mm laminated plate was obtained.

[0009]

[Comparative Example 2] A resin-impregnated base material was obtained in the same manner as in Example 1 except that a pressure roll was not used, and a laminate having a thickness of 1.6 mm was obtained.

Table 1 shows the performance of the laminates of Examples and Comparative Examples 1 and 2. The creeping insulation resistance is the value after immersion for 2 hours in boiling water at 100 ° C, the moisture absorption solder heat resistance is 60 ° C,
The value after 24 hours of treatment in air with a humidity of 95% and the water absorption rate are the values after soaking in water at 23 ° C. for 24 hours.

[0011]

[0012]

The present invention is constructed as described above.
In the method for producing a resin-impregnated base material having the structure described in the claims, it has been confirmed that there is no unimpregnated portion and the heat resistance, insulation property and moisture absorption resistance of the laminated board and the wiring board are improved.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location B32B 27/04 7717-4F Z 7717-4F C08J 5/24 7188-4F // B29K 105: 08 B29L 31:34 4F

Claims (1)

[Claims] 1. A base material is impregnated with a resin and then sent to a drying step,
A method for producing a resin-impregnated base material, which comprises temporarily cooling the resin-impregnated base material in the middle of the drying step, pressurizing, and then drying.