JPH0661617A - Production of printed wiring board - Google Patents

Abstract

PURPOSE:To eliminate defective printing or missing of circuit by cleaning the printing face of a board with ozonic water of specified concentration and then drying the board. CONSTITUTION:Prior to printing with ink, silk screen, etching resist, and the like, a printed wiring board is cleaned for 0.5-180sec with ozonic water of concentration in the range of 0.2-7mg/l and then it is dried. Concentration below 0.2mg/l causes incomplete cleaning whereas concentration above 180mg/l does not enhance cleaning effect. Cleaning may be performed through spraying or immersion and treating time is preferably set at 0.5-10sec for spraying whereas 2-180sec for immersion. No specification is set for drying. This method removes organic substances adhered to the printing face while decomposing into water or carbon dioxide and suppresses missing of circuit.

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 printed wiring board used in electric equipment, electronic equipment, communication equipment, computing equipment and the like.

[0002]

2. Description of the Related Art Conventionally, in the process of manufacturing a printed wiring board, the printed surface is washed by various methods before printing with ink, etching resist, etc., but any of these methods is incomplete and results in defective printing or defective circuits. Was caused.

[0003]

As described in the prior art, the conventional printed wiring board has drawbacks such as defective printing due to poor cleaning of the printed surface and defective circuit missing. The present invention has been made in view of the above problems in the prior art, and an object of the present invention is to provide a method for manufacturing a printed wiring board free from defective printing and defective circuits.

[0004]

The present invention relates to a method for manufacturing a printed wiring board, characterized in that a printed surface of a substrate is washed and dried with ozone water having a concentration of 0.2 to 7 mg / l before pattern printing. Therefore, the organic substances attached to the printing surface can be decomposed and removed into water and carbon dioxide gas, and the above object can be achieved. The present invention will be described in detail below.

An inner layer material for a printed wiring board used in the present invention,
As the resin used for the prepreg and the outer layer material, epoxy resin, phenol resin, unsaturated polyester resin, vinyl ester resin, polyphenylene oxide resin, silicone resin, polyphenylene sulfide resin, polyethylene terephthalate resin, poly Resins such as butylene terephthalate resin type, polyimide resin type, polybutadiene resin type, fluororesin type, etc. can be used singly, modified products, and mixtures, and if necessary, talc, clay, silica, calcium carbonate, and hydroxide can be used. An inorganic powder filler such as aluminum or a fibrous filler such as glass fiber, asbestos fiber, pulp fiber, synthetic fiber or ceramic fiber may be contained. As the substrate, use woven fabric, non-woven fabric, mat, paper, etc. of inorganic fibers such as glass and asbestos, organic fibers such as polyester, polyamide, polyacrylic, polyvinyl alcohol, polyimide, fluororesin and natural fibers such as cotton. You can As the metal foil, single, alloy, or composite metal foil of copper, aluminum, brass, nickel, iron or the like can be used. As the outer layer material, a single-sided metal foil-clad laminate, a double-sided metal foil-clad laminate, the above metal foil or the like can be used. Thus, before printing the ink, silk screen, etching resist, etc. of the printed wiring board made of the above material,
It is washed with ozone water having a concentration of 2 to 7 mg / l for 0.5 to 180 seconds and then dried. That is, the concentration is 0.2 mg / l
If it is less than 180 mg / l, the cleaning will be incomplete, and the cleaning effect will not change even if it exceeds 180 mg / l. Cleaning is spray,
Any method such as dipping may be used, but in the case of spraying, it is 0.5 to 10
The treatment time is preferably 2 seconds to 180 seconds in the case of immersion. Drying is not particularly limited.

The present invention will be described below based on examples.

[0007]

[Example 1] A 1.2-mm thick 4-layer glass cloth-based epoxy resin printed wiring board was spray-washed on the printed surface with 0.8 mg / l concentration ozone water for 5 seconds, dried and then silk-screen printed. Then, a printed wiring board was obtained.

[0008]

Example 2 A printed wiring board was obtained in the same manner as in Example 1 except that the concentration of ozone water was 5 mg / l and the cleaning time was 120 seconds by immersion.

[0009]

[Comparative Example] A printed wiring board was obtained in the same manner as in Example except that distilled water was used instead of ozone water. Example 1
Table 1 shows the defective circuit loss rates of the printed wiring boards of Comparative Examples 2 and 2 and the comparative example.

[0010]

[Table 1]

[0011]

The present invention is constructed as described above.
In the method for manufacturing a printed wiring board having the configuration described in the claims, there is an effect of reducing the defective circuit.

Claims (2)

[Claims] 1. A substrate printing surface is coated with 0.2 to before pattern printing.
A method of manufacturing a printed wiring board, comprising cleaning and drying with ozone water having a concentration of 7 mg / l. 2. The method for manufacturing a printed wiring board according to claim 1, wherein the cleaning treatment time is 0.5 to 180 seconds.