JPS61124577A - Method for forming chemical plating on insulator - Google Patents

Abstract

PURPOSE:To form a chemical plating layer having high adhesive power on an insulator by roughening chemically the surface of the adhesive agent layer deposited on the surface of an insulator and grinding the surface to the surface of an insulator and grinding the surface to the extent of not occluding gas then executing chemical plating. CONSTITUTION:The adhesive agent layer 12 such as phenolic 'sumilite(R)' resin is deposited on the surface of the insulator 11 provided on a metallic plate 10. The surface of the layer 12 is then chemically roughened by using chromic acid mixture, etc. The chemically roughened surface is then ground by brushing to the surface condition to the extent of not occluding the gas such as hydrogen generated in the stage of chemical plating in the surface, more particularly the recessed part of the layer 12. The chemical plating layer 13 having the high adhesive strength to obviate blistering is formed on the insulator 11.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a method of forming chemical plating on an insulator, and more specifically, a method of forming an adhesive layer on an insulator and chemically roughening the surface. After that, it relates to a method of forming chemical plating.

(Prior art) The technology of depositing a metal layer on the surface of an insulator such as plastic or glass is used for electrical appliance parts, automobile parts, decorations,
There are too many examples of its applications, including electronic components. The method of depositing a metal layer on the surface of such an insulator is carried out by chemical plating, and is well known as an additive method. In both the fully additive method, in which metal is deposited on the surface of a nonconductor by chemical plating alone, and the semi-additive method, in which chemical plating and electroplating are combined, the adhesion of the metal layer by chemical plating is insufficient, and the metal layer often separates from the substrate. Encounter peeling problems.

In order to improve this weak adhesion, there is a method of applying an adhesive, for example, as seen in Japanese Patent Publication No. 57-16495, a mixture of acrylonitrile rubber, phenol resin and epoxy resin in specified amounts is used. As shown in Japanese Patent Publication No. 5 "7-18'358," a method of forming a geological layer and making the surface uneven with a chromium sulfuric acid solution is made using thermosetting resin nitrile rubber, phenol-modified epoxy resin, and P.
An adhesive thermosetting resin composition containing a mixture of one or more types of nitro 7eni AJ [, loin bengal, sodium copper chlorophyllin, and one or more types of zinc oxide and zinc hydroxide in a predetermined amount] is applied, and the surface is coated. There are methods of roughening. For all of these adhesives, measures are taken to roughen the surface by chemical or mechanical means. Specific methods for this roughening are also described in the above-mentioned publications, but chemical roughening using chromic acid or the like encounters inconvenient events as shown in FIG.

That is 8! Figure g2 is a model diagram of a microscopic photograph of a process cross section immediately after the surface of the adhesive was roughened with chromium sulfuric acid as chemical roughening. The advantage of chemical roughening such as chromium sulfate over mechanical roughening such as sandblasting is that, as can be understood from the model diagram shown in Figure 2, the surface condition of the surface is extremely complex. It is to be. Therefore, the chemically plated layer deposited on this surface will not be easily peeled off.

(Problems to be Solved by the Invention) However, the only drawback is that gases generated during chemical plating, such as hydrogen gas, are occluded inside the dendritic, uneven surface. The hydrogen gas 2 trapped deep within the uneven adhesive 1 eventually pushes up the chemical plating layer (not shown) and appears as a blistering phenomenon.

Such a phenomenon leads to disconnection and poor adhesion. still,
3 is an insulating substrate.

Therefore, this invention is a process of applying chemical plating to an insulating plate by applying an adhesive, and in particular, even if the surface layer of this adhesive is chemically roughened, the chemical plating layer does not blister and has high heat resistance. The object of the present invention is to obtain a method that exhibits adhesion.

(Means for Solving the Problem) This invention involves chemically roughening the surface of an adhesive, and then applying a chemical plating process to the surface layer to the extent that air bubbles generated during the chemical plating process are not introduced into the adhesive. Grinding is performed prior to grinding.

(Function) The characteristic effect of this invention is that although it is a chemically roughened adhesive, it has a rough surface that does not absorb air bubbles during the chemical plating process, so it is particularly effective in improving the adhesion of chemical plating. It works.

(Example) A preferred embodiment of this invention will be described with reference to the drawings.

FIG. 1 is a cross-sectional view showing the manufacturing process of a printed circuit board with a metal core based on the method of the present invention. The surface is coated with an insulator 1 by a method or the like, and an adhesive layer 12 is formed to provide adhesion between the insulator 11 and the conductor circuit 13 formed thereon.

The adhesive 12 may be the composition shown in the above-mentioned publication, but in this example, phenolic Sumilite resin was used. Next, as shown in (b), the adhesive layer 12 was roughened with chromium sulfuric acid. Next, as shown in (C), the roughened surface layer of the adhesive layer 12 was ground. The amount of this grinding varies depending on the roughening time in the step (b), the adhesive used, or the solvent used during grinding, so it is difficult to describe it quantitatively, but the roughened adhesive layer 120 Approximately half of the surface layer is ground 0, that is, appropriately ground so that bubbles such as hydrogen gas generated during chemical plating in the next step are not occluded deep into the roughened adhesive layer 12. Please note that if this grinding is performed excessively, the adhesion of the chemical plating layer 13 shown in step (d) will be significantly reduced.

For grinding, a method using brushing was tried. Brushing materials were nylon, hair, and wire brushes, but nylon bran was better in terms of hardness. The incidence of blisters was lower when brushing was done in multiple directions, that is, in a random manner, than when brushing in a single direction. This is because the roughening by chromium sulfate in step (b) does not show any directionality.

That is, with unidirectional brushing, it is possible that uneven portions smaller than the thickness of the brush may not be ground at all.

Therefore, it is preferable to rub randomly from multiple directions. More specifically, it is wise to perform brushing while applying appropriate rotation and reciprocating motion.

The surface of the adhesive layer 12 has been scraped by mechanical grinding means such as brushing, and the adhesive layer 12 has an uneven state that does not contain bubbles such as hydrogen gas generated in the next process. A chemical plating layer 13 is deposited on the surface as shown.

From now on, in the semi-alloy tip method, this chemical plating layer 1
An electroplated layer is formed on the printed circuit board.
Further, setering is performed, but detailed explanation of each of these steps will be omitted.

(Effects of the Invention) According to the method of this invention, by chemically roughening the surface of the adhesive layer and further grinding the surface layer by mechanical means, gas generated during chemical plating is not absorbed, but complex unevenness is formed. Since the surface layer of the adhesive can be formed with a certain amount of moisture, a chemical plating layer with high adhesion that does not cause blistering can be applied thereon, which is a great advantage.

[Brief explanation of the drawing]

FIGS. 1(a) to 1(d) are process cross-sectional model diagrams showing a preferred embodiment of the present invention. FIG. 2 is a model diagram of a microscopic photograph of a cross-sectional view of the process immediately after the surface of the adhesive has been chemically roughened. DESCRIPTION OF SYMBOLS 10... Metal plate, 1... Insulator, 12... Adhesive layer, 13... Chemical plating layer. Patent Applicant: Oki Electric Industry Co., Ltd. Figure 1 (a) (b) (c) (d) Procedural amendment (restraint 1) Indication of case 1982 Patent Application No. 243196 2, title of invention on insulator Method of forming chemical plating 3, relationship with the case of the person making the amendment Patent application Seisakusho (〒105) 1-7-12-4 Toranomon, Minato-ku, Tokyo
, agent

Claims (1)

[Claims] (1) In the method of depositing an adhesive layer on the surface of an insulator and chemically roughening the surface of this layer to form a chemical plating layer,
Prior to forming the chemical plating layer, it includes a step of grinding the chemically roughened surface layer of the adhesive layer by brushing, and the amount of grinding is determined so that the amount of grinding is determined by the amount of gas generated during the formation of the chemical plating layer on the surface of the adhesive layer. A method of forming chemical plating on an insulator, which is characterized in that the process is carried out until the surface has a state in which no occlusion occurs in recesses.