JPH07256691A - Manufacture of double injection molded circuitry - Google Patents

Abstract

PURPOSE:To provide a manufacturing method of a new double injection molded circuitry, which facilitates the mounting of a primarily injection molded body to a mold and enhances productivity. CONSTITUTION:A plurality of positioning pins 9 having semi-circular crosssection are provided in a secondary injection mold are provided. At the same time, at the projections of primarily molded bodies 4 (A) and 4 (B), a plurality of through holes having elliptic crosssection are provided so as to fit the through holes of the primarily molded bodies 4 (A) and 4 (B) onto the positioning pins 5 of the secondary injection mold for mounting.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is a double injection composed of a primary molded body made of a resin containing a catalyst for electroless copper plating and a secondary molded body made of a resin not containing a catalyst for electroless copper plating. The present invention relates to a method for manufacturing a molded circuit component.

[0002]

2. Description of the Related Art Conventionally, among injection molded circuit parts constituting electric parts and electric circuits, there is a so-called double injection molded circuit part made of different resins.

As shown in FIG. 4, this double injection molded circuit component a is formed, for example, in the shape of a flat plate. This is shown in FIG. 5, starting with resin A containing a catalyst for electroless copper plating. After the primary molded product b in which the uneven portions g and d and the communication holes f are formed is injection-molded and the primary molded product b is placed in the mold C as shown in FIG. 6, the primary molded product b is obtained. The resin B containing no catalyst for electroless copper plating is secondarily injection-molded in the recess g, that is, the space between the primary molded product b and the mold C to form a secondary molded body c. Time injection molding a
To form. Thereafter, the surface of the convex portion d of the primary molded product b exposed on the surface of the double injection molded body a and the convex portion d thereof.
After roughening the inner surfaces of, for example, the two through-holes e formed in step 1, the electroless copper-plated film H is formed on the inner surface of the two through-holes e, thereby forming an electric conductor circuit on both sides of the double injection molded body a. In addition, these electrical conductor circuits are connected by the electroless copper plating film H formed on the inner surface of the through holes e, e.

[0004]

By the way, there are the following problems in manufacturing such a double injection molded part a.

First, in order to injection-mold a primary molded product b having a plurality of through holes e ..., The number of through holes e ... And communicating holes f ... Is provided in the primary molding die (not shown). It is necessary to provide a plurality of pins (not shown) according to the above, and the die (not shown) of the primary molded product b has a complicated structure.

Next, when the resin B is secondarily injection-molded to the primary molded product b to form the secondary molded product c, the inner surface of the through hole e of the primary molded product b is the secondary molded product c. It is necessary to fit the positioning pins h of the secondary molding die to this portion so as not to be covered by the above. However, the pins h ... Do not form a gap with the inner surface of each through hole e. Since extremely high precision is required, it takes time to fit the positioning pins h ... And the respective through holes e ... The highly accurate positioning pins h ... May be bent due to the injection pressure of the resin B loaded through the primary molded product b when B is injected.

Therefore, the present invention has been devised in order to effectively solve the above problems, and its purpose is to simplify the structure of the primary molding die and to attach the primary injection molded body. It is an object of the present invention to provide a novel method for producing a double-injection molded circuit component, which makes it easy to prevent damage to the positioning pins of the secondary molding die.

[0008]

A first aspect of the invention for solving the above-mentioned problems is a plate-shaped article having a protrusion on both sides of a resin (hereinafter referred to as resin A) containing a catalyst for electroless copper plating. After injection-molding the primary molded body, and mounting the primary molded body in the mold for secondary injection molding, electroless copper plating around the primary molded body with only the protrusions exposed. Resin without catalyst (hereinafter referred to as Resin B)
To form a secondary molded body to form a substantially flat plate-shaped double-injection molded body, and thereafter, the surface of the exposed portion of the primary molded body is roughened, and the roughened portion is electrolessly treated. In a double injection molded circuit component in which an electric conductor circuit is formed by forming a copper plating film, a plurality of positioning pins are provided in the mold for the secondary injection molding, and a plurality of positioning pins are provided on the protrusion of the primary molded body. A through hole having an elliptical cross section is formed, and when the double injection molded body is formed, the through hole of the primary molded body is fitted and attached to the positioning pin of the mold. Of the present invention, injection molding a plate-shaped primary molded body provided with a protrusion having an elliptical through hole in the periphery by using the above resin A, and positioning the primary molded body inside to fit the through hole. After fixing in the mold for secondary injection molding equipped with pins for On both sides of the following moldings, substantially flat twice injection molded and without forming a secondary molded body by injecting the resin B while exposing only the protruding portions, then,
After roughening the surface of the projection of the primary molding and the inner surface of the through hole exposed on the surface of the twice-injection molded body, an electroless copper plating film is applied to that portion to form an electric conductor circuit on both sides. Is formed to electrically connect these electric conductor circuits, and the third invention is such that the through hole has a rectangular cross section.

The base resin of the resin A containing the electroless copper plating catalyst is not particularly limited, but for example, one kind or a mixture of polyether sulfone, polyether imide, polyoxybenzoic acid, etc., Alternatively, a composite resin prepared by blending them with an inorganic filler can be used. On the other hand, as the resin B containing no catalyst for electroless copper plating, those different from the above resin A, such as polyphenylene sulfide, polyethylene terephthalate and the like are suitable, but if the combination is changed, the above polyether sulfone, polyether imide, Polyoxybenzoic acid can be used.

[0010]

The present invention makes it possible to reduce the number of pins of the die for the primary molded body by making the shape of the through-hole of the primary molded body an elliptical cross section as described above. The structure of the mold can be simplified. That is, as shown in the above problems, the conventional primary molded body has a through hole for electrically connecting the communication hole for communicating the resin B injected into the recess and the electric conductor circuit. In order to achieve this, two types of pins were required, but in the present invention,
By using a pin having an elliptical cross section, a communication hole and a through hole can be formed at the same time, and one type of pin is sufficient. In addition, by making the through hole of the primary molded body elliptical in cross section and forming the positioning pin of the secondary injection molding die in a semicircular cross section in this way, it is possible to position the secondary injection molding die. Since it is possible to easily fit the through hole of the primary molded body to the pin for easy mounting, and the gap corresponds to the conventional communication hole, the secondary molded body by injection of the resin B is formed. Is formed well as before. Further, by forming the positioning pin of the secondary injection molding die in a semicircular cross section in this way, the strength of the positioning pin is improved, and deformation due to injection pressure and damage during mounting of the primary molded body are prevented. It can be prevented.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

1 and 3 show one embodiment of a double injection molded circuit component 1 formed by the method of the present invention. As shown in the figure, in the double injection molded circuit component 1 formed into a substantially flat plate, electric conductor circuits 2 and 2 in which the electroless copper plating film H is applied to both surfaces of the double injection molded body 1a are formed. Around it, a secondary molded body 4 (B) made of a resin B containing no electroless copper plating catalyst is provided. Further, the double injection molded circuit component 1 is formed with two through holes 3 and 3 having a semicircular cross section, and the inner surface thereof has the same electroless copper plating film as the electric conductor circuits 2 and 2. H is applied to electrically connect the electric conductor circuits 2 and 2 to each other.

The electric conductor circuits 2 and 2 and the through holes 3 and 3 to which the electroless copper plating film H is applied are composed of a primary injection molded body 4 (A) as shown in FIG. As shown in the figure, this primary injection molded body 4 (A) is injection molded from a resin A containing a catalyst for electroless copper plating, and projections 6 are formed on both sides of a substrate 5 thinner than the double injection molded circuit component 1. And, two through holes 7, 7 having an elliptical cross-section are formed so as to span the protrusion 6. Then, on the protruding portion 6 side of the two through holes 7, 7, the positioning pin 9, of the secondary injection mold 8 shown in FIG.
9 is fitted, and the resin B is injected into the gap.

Next, one embodiment of the method of the present invention will be specifically described.

First, a polyether sulfone blended with 5 wt% of clay adsorbing 0.1 wt% of palladium, which is a catalyst for electroless copper plating, and 30 wt% of glass fiber was used as a resin A, and as shown in FIG. 5 and protrusion 6
And a primary molded body 4 having two through-holes 7, 7 having an elliptical cross section and straddling the substrate 5 and the protrusion 6.
(A) was injection molded. Since a primary injection mold (not shown) for injection-molding this primary molded body 4 (A) uses a pin (not shown) having an elliptical cross section, it is used for through holes and communication as in the conventional case. The structure was simplified compared to the primary injection mold using a pin for holes, and injection could be easily achieved.

Next, as shown in FIG. 3, the primary molded body 4 (A) taken out from the primary injection mold has its through holes 7,
After inserting a positioning pin 9 having a semicircular cross section provided in the secondary injection molding die 8 so as to abut the projection 6 side of 7 and fixing it in the die 8, a catalyst for electroless copper plating Polyphenylene sulfide mixed with 30 wt% of glass fiber not blended with is used as the resin B, and this is injected into the space between the primary molded product 4 (A) and the mold 8 and the positioning pin 9 to produce the secondary molded product 4 ( B) was formed to form a flat secondary injection-molded body 1a. As a result, the resin B is injected into the space between the positioning pin 9 and the through holes 7, 7 and the primary molded body 4
Secondary molded bodies 4 (B) are formed above and below (A), and through holes 3, 3 having a semicircular cross section are formed. afterwards,
When the surface of the polyether sulfone portion exposed on the surface of the double injection molded body 1a is roughened and an electroless copper plating film is applied, a good copper plating film H is formed on the surface of the polyether sulfone. I was able to. At this time,
Since the through holes 7, 7 of the primary molded body 4 (A) have an elliptical cross section, the mounting in the secondary injection molding die 8 can be easily achieved, and the injection pressure of the resin B can be used. No deformation of the positioning pin 9 was observed.

Also, as a second embodiment of the present invention, when the through holes 7, 7 are changed from elliptical to rectangular in cross section,
In addition to being able to form a good electroless copper-plated film, the same effects as those of the above-described examples were obtained.

[0018]

As described above in detail, according to the present invention, since the number of pins of the primary injection mold can be reduced, the structure of the mold can be simplified and the mold can be easily manufactured.
Further, since the shape of the through-hole of the primary molded body is elliptical in cross section, it becomes easy to mount it on the secondary injection mold,
Workability and productivity can be improved. Furthermore, by making the positioning pin of the secondary injection molding die semi-circular in cross section, the strength is improved and deformation and damage due to the mounting of the primary molding and the injection pressure are reduced. Has an excellent effect in that it can easily contribute to the improvement of productivity.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a double injection molded circuit component obtained by the method of the present invention.

FIG. 2 is a perspective view showing an example of a primary molded body according to the method of the present invention.

3 is a secondary injection molding die and a sectional view taken along the line I-I in FIG. 1. FIG.

FIG. 4 is a perspective view showing an example of a conventional double injection molded circuit component.

FIG. 5 is a perspective view showing an example of a primary molded body that constitutes a conventional double injection molded circuit component.

FIG. 6 is a sectional view taken along the line II in FIG. 4 of a conventional secondary injection molding die.

[Explanation of symbols]

 1 Double injection molded circuit component 1a Double injection molded body 3 Semi-circular cross-section through hole 4 (A) Primary molded body 4 (B) Secondary molded body 6 Projection portion 7 Elliptical cross-sectional through hole 8 For secondary injection molding Mold 9 Positioning pin

Claims (3)

[Claims] 1. A plate-shaped primary molded article having projections on both sides is injection-molded using a resin containing a catalyst for electroless copper plating (hereinafter referred to as resin A), and the primary molded article is secondary molded. After being mounted in a mold for injection molding, a resin containing no electroless copper plating catalyst (hereinafter referred to as resin B) is injected around the primary molded body while exposing only the above-mentioned protrusions. Then, a secondary molded body is formed into a substantially flat plate double injection molded body, and then the surface of the exposed portion of the primary molded product is roughened and electroless copper plating is applied to the roughened portion. In a method for manufacturing a double injection molded circuit component in which a film is formed to form an electric conductor circuit, a plurality of positioning pins having a semicircular cross section are provided in the mold for secondary injection molding, and the primary Providing multiple through-holes with an elliptical cross-section on the protrusions of the molded product, A double-injection molded circuit component, characterized in that, when forming a double-injection molded body, the through-holes of the primary molded body are fitted and attached to the positioning pins of the secondary injection molding die. Manufacturing method. 2. A plate-shaped primary molded body provided with a protrusion having a through hole having an elliptical cross section on both sides using the resin A, is injection-molded, and the primary molded body is fitted into the through hole. After fixing in a mold for secondary injection molding provided with a positioning pin having a semicircular cross section, the resin B is injected around the primary molded body with only the protruding portion exposed. A secondary molded body is formed into a substantially flat-shaped double injection molded body, and then the surface of the protrusion of the primary molded body and the inner surface of the through hole exposed on the surface of the double injection molded body are removed. After the roughening treatment, an electroless copper plating film is applied to the portion to form electric conductor circuits on both surfaces, and these electric conductor circuits are electrically connected to each other, and a method of manufacturing a double injection molded part. 3. The method of manufacturing a double injection molded part according to claim 1, wherein the through hole is formed in a rectangular cross section.