JPH05226830A - Molded product of metal or ceramic for printed wiring and manufacture thereof - Google Patents

Abstract

PURPOSE:To make it possible to eliminate a conventional operation of securing a printed wiring board on a molded product with an adhesion or a bolting and manufacture easily and economically, by directly forming a printed wiring on the molded product of metal or ceramic through an aromatic polyamide-imide resin composition layer having an organic solvent solubility. CONSTITUTION:An aromatic polyamide-imide resin solution is applied to a predetermined part of a molded product 1 of metal or ceramic, and is dried with a far infrared dryer, etc., and a heat resistant insulating resin layer 2 is formed. Next, a printed wiring is formed on the insulating resin layer 2 by, for example, a subtractive process. That is, a copper foil 3 is placed on the resin layer 2 semidried to the degree having an adhesion and is laminated by heating and pressurizing. A wiring pattern 4 is formed on the copper foil 3 using a pattern resist. After etching, the resist is removed. Thus, the molded product 1 can be manufactured easily and economically. Further, the decrease in resistance to heat or moisture and the.limit of thinning or lightening can be overcome.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal or ceramic molded product with printed wiring, in which a printed wiring is directly provided on a metal or ceramic molded product via an aromatic polyamideimide resin layer, and a method for producing the same.

[0002]

2. Description of the Related Art With the demand for higher density and lower cost of electronic and electric devices, there is a strong demand for development of parts having a predetermined shape in which printed wiring is integrated. In response to this, molded circuit parts manufactured by injection molding engineering plastics have been developed.

However, for metal or ceramic parts, there is no suitable molding technique such as injection molding of plastics, and molded circuit parts of plastics have not been realized so far. Therefore, in the case of metal or ceramic parts, a printed wiring board obtained by forming a printed circuit on a copper clad laminate for printed circuits by a conventional method has been conventionally molded separately, and then adhered to the necessary parts of the metal or ceramic parts. The parts manufactured by the method of fixing with an agent or bolting were used.

This conventional method requires post-processing such as punching, chamfering and punching for mounting a printed wiring board, a fixing process such as application of an adhesive and bolt tightening, and a special device for alignment. In addition, there is a problem in that it takes time and labor, and there is a limit in the total thickness due to the base material and the adhesive constituting the printed wiring board, and it is difficult to further reduce the thickness and weight. It was

[0005]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the conventional metal or ceramic parts with a printed wiring, and does not require fixing work such as bonding or bolting of the printed wiring board, Simple and economical manufacturing is possible,
And heat resistance derived from the printed wiring board substrate or adhesive,
It is an object of the present invention to provide a metal or ceramic molded product with a printed wiring, which overcomes the drawback of moisture resistance and the limitation of thinning and weight reduction.

[0006]

Therefore, the inventor of the present invention, if there is a resin having heat resistance, humidity resistance, dimensional stability especially under heat and humidity, good workability and adhesiveness, and an insulating property, Based on the idea that a circuit can be directly formed on a metal or ceramic molded product as an insulating layer and an adhesive layer, as a result of diligently searching for such a resin, use of a specific organic solvent-soluble aromatic polyamideimide resin As a result, they have found that the problems of the present invention can be solved all at once, and completed the present invention.

That is, the present invention provides a molded article of metal or ceramics with printed wiring, in which printed wiring is directly provided on a molded article of metal or ceramics via a layer composed of an organic solvent-soluble aromatic polyamide-imide resin composition. In order to obtain the above, after applying an aromatic polyamide-imide resin composition dissolved in an organic solvent to a predetermined portion of a metal or ceramic molded product, a printed wiring can be directly formed thereon by a subtractive method or an additive method. The present invention provides a method for producing a molded product of a metal or a ceramic with a printed wiring characterized by the above.

The present invention will be described in detail below. The organic polar solvent-soluble aromatic polyamideimide resin used in the present invention has the general formula

[0009]

[Chemical 1] However, R is a hydrogen atom, a halogen atom, or an alkyl group, and X represents an oxygen atom, a sulfur atom, or a sulfonyl group. Among these, an aromatic polyamideimide resin having R as a hydrogen atom and X as an oxygen atom, for example, 4,4′-diaminodiphenyl ether as an aromatic diamine component is preferable.

A reduced viscosity of 0.8 to 3.5, preferably 0.1 to 3.0 is used. If the reduced viscosity is too low, there are problems in heat resistance and flexibility, and cracks tend to occur after film formation. Further, if the reduced viscosity is too high, the compatibility decreases, which is not preferable. In addition, the above-mentioned resin has a high thermal conductivity filler such as beryllia (BeO), magnesia (MgO), boron nitride (BN), alumina (Al ₂ O).
₃ ), silicon carbide (SiC), silicon nitride (Si
Even better results are obtained by adding 1 to 3% by volume of ₃ N ₄ ), mica and mixtures thereof.

The above-mentioned aromatic polyamide-imide resin used in the present invention can be produced by a known method, for example, by reacting an aromatic diamine and trimellitic anhydride chloride in an organic polar solvent, or by mixing an aromatic diisocyanate and trimellitic anhydride with an organic solvent. It can be produced by reacting in a polar solvent. Further, since SOXR (registered trademark) marketed by Nippon Koshigami Kogyo Co., Ltd. is the above-mentioned suitable aromatic polyamide-imide resin, it can also be used.

As the aromatic diamine used in the present invention, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfone, 4,4'-diaminobenzophenone,
4,4'-diaminodiphenylmethane can be mentioned. Among these, 4,4′-diaminodiphenyl ether is particularly preferable from the viewpoint of moisture resistance.

As the organic solvent for the aromatic polyamide-imide resin, N, N-dimethylformamide, N, N-
Dimethylacetamide, dimethylsulfoxide, N-methyl-2-pyrrolidone, hexamethylphosphoramide,
Examples thereof include halogenated cresol or a mixed solvent thereof, or a mixed solvent of these and another conventional solvent. Of these, N, N-dimethylacetamide and N-methyl-2-pyrrolidone are particularly preferable.

The molded article of metal or ceramics to which the present invention is applied is mainly used as a part of electronic / electrical equipment, and the material thereof is metal, such as aluminum, iron, stainless steel, silicon steel, or the like, or Ceramics such as alumina, porcelain, glass and the like.

To give some specific examples, lead parts, connectors, motor switches, and other parts with reinforcing plates, parts that require heat radiation, electromagnetic wave shielding, and electrical characteristics, or various high-density mounting parts Etc.
Especially, the floppy disk drive (FD
It is preferably used as a head component for D).

The following method may be used to produce a molded article of metal or ceramics with a printed wiring according to the present invention.
FIG. 1 shows an outline of the steps of the manufacturing method of the present invention.
That is, (1) the above-mentioned aromatic polyamide-imide resin solution, for example, SOXR (registered trademark) manufactured by Nippon Koshigami Kogyo Co., Ltd., is applied to a predetermined portion of the metal or ceramic molded article 1 and dried using a far infrared dryer or the like. Then, the heat resistant insulating resin layer 2 is provided.

As a coating method, a known screen printing method, blade coaster method, metal mask printing method, roll coater method, or the like is used. Among them, the screen printing method is simple and preferable. When the copper foil is laminated, it is preferable to dry after coating at 80 to 150 ° C., preferably about 100 ° C. for several minutes. When the conductive paste is printed on it and used, more It is advisable to dry completely, i.e. at 150 to 250 [deg.] C., preferably about 200 [deg.] C. for a few minutes.

(2) Next, a printed wiring is formed on the heat resistant insulating resin layer 2 obtained in (1) by either of the following two methods. Subtractive method (a) The above resin layer 2 semi-dried to the extent that it has adhesiveness
The copper foil 3 is placed on top of the above, and heated and pressed (laminating press) to be laminated.

(B) A printed wiring (pattern) is formed by a known subtractive (etching) method in which a wiring pattern 4 is formed on the copper foil using a pattern resist, the resist is peeled off after etching. (C) Further, an overcoat layer 5 is provided by screen printing or film laminating on a required portion of the printed wiring, and a rust preventive film (flux, solder coat, plating, etc.) 6 is applied to the exposed wiring portion.

Conductive paste printing method (a) Conductive paste 7 is formed on the completely dried resin layer.
Is screen-printed to form a predetermined wiring circuit. (B) The overcoat layer 5 is provided at a required portion of the wiring circuit by screen printing or film lamination,
Further, a rust preventive film (flux, solder coat, plating, etc.) 6 is applied to the exposed wiring portion.

[0021]

The present invention will be described in the following examples. Example 1 From a stainless plate having a thickness of 0.2 mm, a length of 17.0 mm and a width of 1
4.0mm rectangular floppy disk drive (F
It is manufactured by punching out the gimbal plate of the head part for DD).
SOX made by Nippon Koshigami Co., Ltd. on the stainless plate
A solution of R (solvent-soluble aromatic polyamide-imide resin: registered trademark) was screen-printed at a thickness of about 20 μm for 8.9.
After being applied to a rectangle of mm × 10.0 mm, it is dried at 100 ° C. for 5 minutes by a far infrared dryer or the like to form a semi-dried insulating layer.

A commercially available copper foil (35 μm) is placed on it,
20 ~ 30kg / for 20 minutes at 180 ℃ using a heat press
Laminate under pressure of cm ² . A predetermined wiring pattern is formed on the copper foil using a commercially available resist (a dry film type etching resist manufactured by Hitachi Chemical Co., Ltd.) through an exposure to development process to form a resist pattern.

Next, this is etched with an alkaline etching solution at 50 to 55 ° C. for 1 to 2 minutes, and then the pattern resist is treated with a methylene chloride solution for 1 to 2 minutes to be peeled off. Next, this is heated stepwise, and finally 200 ° C.
And heat for about 5 minutes to perform main drying. Furthermore, the above S
An overcoat is provided at a required location by screen printing using an OXR liquid, and then the exposed wiring portion is plated to obtain an intended FDD head component with printed wiring.

As a comparative example to this, the same printed wiring was formed on the copper clad laminate of copper foil 35 μm and polyimide base film 12.5 μm by the same subtractive method as described above, and overcoating and soldering were performed in the same manner. Table 1 shows the performance of the conventional component in which the produced printed wiring board was bonded to the stainless steel plate of the same FDD head component as described above with an acrylic adhesive. From the results of Table 1, it can be seen that the printed wiring part of the present invention is superior to the conventional ones in terms of inter-line insulation, solder heat resistance, adhesion, and thickness.

Example 2 In the same manner as in Example 1, a stainless steel plate gimbal plate coated with the same SOXR as in Example 1 is prepared. The drying of SOXR is different from that in Example 1, and is 200 ° C. in a far infrared dryer.
Completely dry for 5 minutes to form an insulating resin layer. A copper paste made of Tatsuta Electric Wire is screen-printed thereon to form a predetermined wiring pattern. Use this far infrared dryer for 15
Dry at 0 ° C for 5 minutes.

Next, an overcoat is provided at a required portion by screen printing using an epoxy solder resist, and then an exposed wiring portion is subjected to rust preventive flux to obtain an FDD head component. The performance of this product was superior to that of the conventional product as in Example 1.

[0027]

[Table 1]

[0028]

The metal or ceramic molded product with a printed wiring according to the present invention does not require the work of fixing the printed wiring board to the molded product by adhesion or bolting as in the prior art, and the post-processing for the printed wiring board and the related work. In addition to the effect that it can be manufactured extremely easily and economically without the need for molds, etc., it also has the effect of overcoming the limitations of heat resistance and moisture resistance due to adhesion or printed wiring boards, and thinning and weight reduction. Have.

[Brief description of drawings]

FIG. 1 is a sectional view showing an outline of steps of a manufacturing method of the present invention.

[Explanation of symbols]

 1 Part of metal or ceramic molded product 2 Heat-resistant insulating resin (aromatic polyamideimide) layer 3 Copper foil 4 Pattern resist 5 Overcoat 6 Solder 7 Conductive paste

Claims (3)

[Claims] 1. A molded article of metal or ceramics with printed wiring, wherein printed wiring is directly provided on a molded article of metal or ceramics through an organic solvent-soluble aromatic polyamideimide resin composition layer. 2. A metal or ceramic molded article is coated with an aromatic polyamideimide resin composition dissolved in an organic solvent at a predetermined position, and then a printed wiring is directly formed thereon by a subtractive method or an additive method. A method for producing a molded article of metal or ceramics with a printed wiring, comprising: 3. The printed wiring metal or ceramic according to claim 2, wherein an overcoat is provided at a predetermined position of the formed printed wiring, and a rust preventive film is provided on the exposed wiring portion. Molded article manufacturing method.