JP2516650B2 - Molded circuit board manufacturing method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for manufacturing a molded circuit board in which a circuit pattern and a resin molded body are integrally formed.

[Prior Art] Conventionally, there is known a method of molding a circuit pattern on a resin molded body using an injection molding method. In this method, a conductive paste circuit pattern is first printed on a flexible base sheet. In the case of multiple layers, after forming an insulating layer with an insulating paste on it, a circuit pattern is further printed with a conductive paste and laminated. In this way, a transfer sheet having a circuit pattern layer formed in a peelable state on the surface by a known technique is prepared, and the transfer sheet is set in the cavity of a molding die with the circuit pattern side facing up. After that, a molten resin is injected into the mold cavity to perform molding to mold a circuit pattern on the surface of the resin molded body. Of course, there is also a method of directly setting a circuit film without a base sheet such as a transfer sheet in a mold.

However, in these methods, the circuit film set in the mold is misaligned during resin injection into the mold, and the circuit film to be molded during the injection molding may be deformed or damaged. was there. This problem is large in the case of a large resin molded body that requires a particularly high injection pressure, in the case where there are many irregularities such as ribs, and when a resin having poor fluidity is used.

[Object of the Invention]

In view of the above problems, an object of the present invention is to provide a method for manufacturing a molded circuit board, which can prevent the circuit film from being displaced in the molding die and can be set accurately at a desired position.

[Structure of Invention]

In order to achieve the above object, the present invention provides a method for producing a molded circuit board in which a resin film and a circuit pattern are integrated by setting a circuit film having a circuit pattern in a molding die and molding the resin. In, in the cavity of the molding die, the circuit film set surface is provided with a fitting protrusion for positioning corresponding to the reference hole of the circuit film, and the reference hole of the circuit film is fitted into the fitting protrusion. It is characterized in that the resin is molded in the state.

Example of Invention

Embodiments of the present invention will be described below in detail with reference to the drawings. 1 and 2 show an embodiment of the present invention. First, in the method for manufacturing a molded circuit board according to the present invention, first, the fitting projection 3 is provided on the circuit film setting surface of the mold, specifically, on the circuit film setting surface of the movable mold 2 shown in FIG. On the other hand, the circuit film 1 having the circuit pattern is also provided with the reference holes 4 at positions corresponding to the fitting protrusions 3 in advance. And this circuit film 1
When the is set on the circuit film setting surface of the movable mold 2, the reference hole 4 of the circuit film 1 is fitted into the fitting protrusion 3 of the mold and set, and then the mold is closed. In this state, molten resin is injected into the cavity 7 from the sprue 6 provided on the fixed mold 5 through the gate 8 to manufacture a molded circuit board in which the resin molded body and the circuit pattern are integrated. is there.

The number and shape of the reference holes 4 provided in the circuit film 1 and the fitting protrusions 3 provided on the mold side are appropriately determined depending on the size of the circuit film 1 and the circuit pattern of the circuit film 1. It is not limited to those shown in FIGS. The circuit film 1 referred to herein means a circuit film in a broad sense, and includes, for example, a film having a circuit pattern layer on a base sheet, a so-called transfer film, and also includes a circuit film in which the base sheet is omitted. . Further, in the above-described embodiment, the fitting protrusion 3 is provided on the movable mold 2 side in the cavity 7, but depending on the shape of the mold circuit board to be obtained, the fixed mold 5 may be provided.
It may be provided on the side.

In this way, the fitting projection 3 for positioning is provided on the mold side, and the reference hole 4 corresponding to this fitting projection 3 is also provided on the circuit film 1 side, and both are fitted together. By molding with, it is possible not only to prevent the displacement of the circuit film 1 when injecting the resin, but also to position the circuit film 1 with higher accuracy, and thus to obtain a molded circuit board with high accuracy efficiently. You can

〔The invention's effect〕

As described above, according to the present invention, the accuracy of the set position of the circuit film is remarkably improved, and the position shift of the circuit film in the cavity during the injection molding can be prevented, and thus the efficiency and the position accuracy can be improved. A high molded circuit board can be obtained.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a molding die according to an embodiment of the present invention, and FIG. 2 is an enlarged perspective view of the cavity portion shown in FIG. 1 ... Channel film, 2 ... Movable mold, 3 ... Fitting protrusion, 4 ... Reference hole, 5 ... Fixed mold

Claims (1)

(57) [Claims] 1. A method for producing a molded circuit board in which a resin film and a circuit pattern are integrated by setting a circuit film having a circuit pattern in a molding die and molding the resin. A positioning fitting protrusion is provided on the surface of the circuit film set inside the mold cavity so as to correspond to the reference hole of the circuit film, and the resin molding is performed with the reference hole of the circuit film fitted to the fitting protrusion. A method for manufacturing a molded circuit board, which comprises molding.