JP2002314217A - Manufacturing method of plastic formation circuit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a new manufacturing method of a plastic formation circuit with high productive efficiency for forming a superior and highly minute circuit pattern easily. SOLUTION: After a resin mold 6 is formed by using a resin material tending toward easy plating resin through laser irradiation, the laser beam is applied onto the surface thereof and an easy plating pattern base 8 is manufactured. The resin mold 6 is dipped into an electroless solution to form a circuit pattern 4 made of metal plating 3 at the pattern base 8. As a result, the superior circuit pattern 4 having high minuteness can be formed with high productive efficiency.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a portable telephone, a CCD, and the like.
The present invention relates to a method for producing a three-dimensional plastic molded circuit component used for electronic devices such as a camera and an automobile component.

[0002]

2. Description of the Related Art Conventionally, as a method of forming a circuit pattern on a surface of a three-dimensional plastic molded product, a general photographic method (ultraviolet light exposure method) as a method of manufacturing a printed wiring board is used.
And a two-time molding method. In addition, a method utilizing the photoresist technology and etching technology of this photographic method (Japanese Patent Laid-Open No.
286280, JP-A-8-120448, JP-A-9
No. 199838) have also been proposed.

In this photographic method, as shown in FIGS. 3 (1) to 3 (4), after an electroless copper plating layer 2 is formed on the entire surface or a part of a resin molding 1, an ultraviolet curing type A pattern is formed on the surface of the copper plating layer 2 by covering the mask 3 made of resin or the like. Thereafter, the resin molded body 1 is immersed in an etching solution to etch only the copper plating film 2 in a portion not covered with the mask 3, and then the copper plating circuit pattern 4 is formed on the surface by removing the mask 3. It is intended to be formed.

[0004] On the other hand, in the double molding method, a resin in which a catalyst is kneaded into a resin filler so that electroless plating forms a film, and a resin in which electroless plating does not form a film are molded into one molded product. After that, a circuit pattern is formed by forming a film of electroless plating on the resin into which the catalyst has been kneaded.

[0005]

However, the conventional circuit pattern forming method has the following disadvantages.

That is, first, in the photographic method as shown in FIG. 3, as described above, since there are many steps up to the production and the production efficiency is low, the photographic method is not limited to a general printed wiring board. It is difficult to apply inexpensive products such as three-dimensional molded circuit parts in terms of manufacturing cost.

Further, when the etching is performed, a part of the etching solution may reach the copper plating side of the masking portion from the etched portion, and erode the copper plating of the masked portion from the side surface. is there. As a result, as shown in FIG. 3 (4), the pattern of the masking portion becomes significantly narrower than a desired width, and in a finer portion, a part of the pattern is lost, so that it can be used as a circuit. Sometimes you can't.

On the other hand, in the double molding method, since a circuit pattern is formed by a mold, the shape and width of the pattern are limited, and it is extremely difficult to obtain a highly detailed circuit pattern.

Accordingly, the present invention has been devised in order to effectively solve such a problem, and an object of the present invention is to form a high-detailed, high-quality circuit pattern excellent in production efficiency. The present invention provides a novel method for producing a molded plastic circuit component.

[0010]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is to form a resin molded body using a resin which changes to an easily-platable resin by laser irradiation, and then apply a laser to the surface in a pattern. Irradiation processes the pattern base of easy plating, and thereafter, this resin molded body is immersed in an electroless plating solution to form a circuit pattern made of metal plating on the pattern base part. .

That is, the present invention provides a resin molded article
Resin that changes to easily-platable resin by laser irradiation,
Specifically, as described in claim 3, the resin is molded from an SPS resin, and the surface of the resin molded body is irradiated with a laser in a pattern so that only the irradiated portion is surface-modified to be easily plated. is there.

Thus, even when the entire resin molded body is immersed in an electroless plating solution, metal plating is applied only to the surface-modified portion of the resin molded body by laser irradiation. This eliminates the need for many labor-intensive steps such as etching and etching, and also allows the formation of a high-quality circuit pattern free from defects such as erosion of the masked portion. In addition, since it is not necessary to use a mold such as a two-time molding method when manufacturing this circuit pattern, a highly detailed circuit pattern can be easily obtained.

[0013] Further, as described in claim 2, the resin molded body having the metal plating applied to the pattern base portion is further immersed in an electroless Ni plating solution or an electroless Au plating solution to form the metal. In a circuit pattern in which Ni or Au plating is applied on plating, metal plating is further effectively protected by Ni or Au plating, and the durability and connectivity are further improved.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a preferred embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 1 (3) shows an embodiment of a plastic molded circuit component 5 obtained by the method of the present invention.

As shown in the figure, a circuit pattern 4 made of metal plating 7 is formed on a surface of a resin molded body 6 which is a base material (main body) of the plastic molded circuit part 5.

The circuit pattern 4 is formed along a pattern base 8 having a concave cross section from which the resin on the surface is partially removed by laser irradiation.
It is formed in a circuit shape so that the inside is filled with metal plating 7.

In order to manufacture such a plastic molded circuit component 5, first, as shown in FIG. 1A, a resin which changes to an easily plating resin by laser irradiation, for example, an SPS resin (a thin static polystyrene) ) To form a three-dimensional resin molded body 6 having a desired shape by injection molding or the like, and then irradiating the surface thereof with a laser in a pattern as shown in FIG. For example, it is removed to a depth of 10 to 20 μm to process the pattern base 8 having a concave cross section. As a result, the surface of the pattern base 8 is modified by the laser irradiation, and the plating base 8 changes to an easy plating property so that plating can be easily performed.

Next, when an arbitrary pattern base 8 is formed on the surface in this way, the entire resin molded body 6 is immersed in an electroless copper plating solution (20 ° C.). Here, the composition of the electroless copper plating solution is not particularly limited, but for example, the following composition is used.

Copper sulfate about 10 g / dm ³ Rochelle salt about 40 g / dm ³ formaldehyde about 10 g / dm ³ sodium hydroxide about 10 g / dm ³ (pH 12.5) More specifically, copper plating 7 is selectively plated only in the pattern base 8 as shown in FIG.
The desired circuit pattern 4 composed of the copper plating layer is formed by deposition. That is, since the other surface of the resin molded body 6 other than the pattern base 8 is not surface-modified by the laser, the copper plating 7 is not plated, or even if plated, Since the amount is very small, then by lightly polishing the surface,
An extra plating layer can be easily removed.

As a result, since a desired circuit pattern can be obtained in a small number of steps without requiring multiple steps as in the conventional method, excellent production efficiency can be exhibited. In addition, since there is no copper plating etching step, a favorable circuit pattern 4 can be reliably obtained without inconveniences such as thinning of the pattern and loss of the pattern due to over-etching. Further, since the pattern is formed by a laser capable of arbitrarily narrowing the irradiation range, it is possible to easily obtain a highly detailed and dense circuit pattern 4 as compared with pattern forming using a mold.

Further, since the circuit pattern 4 thus obtained is formed without protruding from the surface of the resin molded body 6, even if a stress such as an impact or friction is applied, the circuit pattern 4 can be easily cut or broken. I can't.

Further, as shown in FIG. 2, a protective layer 9 made of Ni plating, Au plating or the like is provided on the circuit pattern 4 made of copper plating to cover and cover the circuit pattern 4. In addition, reliability can be improved, and connectivity with electrical components and the like can be improved.

The surface of the resin molded body 2 on which the circuit pattern 4 is formed as described above is further plated with nickel using an electroless nickel plating bath (45 ° C.) having the following composition. As a result, nickel plating was formed only on the circuit pattern 4 (thickness: 5 μm), and no plating was formed on other portions. Similarly, similar results were obtained when an electroless gold plating solution having the following composition was used. <Electroless Ni plating solution composition> Nickel sulfate about 20 g / dm ³ sodium phosphinate about 15 g / dm ³ citrate about 30 g / dm ³ <Electroless Au plating solution composition> Gold potassium cyanide about 10 g / dm ³ potassium cyanide about 30 g / dm ³ potassium carbonate about 30 g / dm ³ dibasic potassium phosphate about 35 g / dm ^{3 Further} , as described above, the resin used in the present invention is a resin that changes to an easily-platable resin by laser irradiation. Not limited to SPS resin, but also LCP, P
Resins such as PS can be used.

[0025]

In summary, according to the present invention, since excellent production efficiency can be exhibited, the production cost is reduced, and
It can be applied to inexpensive products such as three-dimensional molded circuit parts. In addition, since problems such as thinning of the pattern and loss of the pattern due to over-etching do not occur, a high-quality circuit pattern can be reliably obtained. Further, since patterning is performed by using a laser, it is possible to exhibit an excellent effect that a highly detailed and precise circuit pattern can be easily obtained.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram showing one embodiment of the method of the present invention.

FIG. 2 is a schematic view showing an embodiment of a plastic molded circuit component obtained by the method of the present invention.

FIG. 3 is a process diagram showing an outline of a conventional method of manufacturing a plastic molded circuit component by a photographic method.

[Explanation of symbols]

 5 Plastic molded circuit parts 6 Resin molded body 7 Metal plating 8 Pattern base 9 Protective layer

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H05K 3/24 H05K 3/24 A // H05K 3/10 3/10 EB23K 101: 42 B23K 101: 42 F term (reference) 4E068 AH00 DA09 DB10 5E343 AA12 BB23 BB24 BB44 CC78 DD33 EE32 EE43 GG08

Claims (3)

[Claims] 1. A resin molded body is formed by using a resin which changes to an easily-platable resin by laser irradiation, and then the surface is irradiated with a laser in a pattern to form an easily-plateable pattern base. A method of manufacturing a molded plastic circuit part, wherein the resin molded body is immersed in an electroless plating solution to form a circuit pattern made of metal plating on the pattern base. 2. A resin molded body is formed by using a resin that changes to an easily-platable resin by laser irradiation, and then the surface is irradiated with a laser in a pattern to process an easily-platable pattern base. This resin molded body is immersed in an electroless plating solution to perform metal plating on the pattern base portion, and the metal molded resin molded body is further immersed in an electroless Ni plating solution or an electroless Au plating solution. A method for producing a plastic molded circuit component, characterized in that a circuit pattern is formed by immersing the metal plating and subjecting the metal plating to Ni or Au plating. 3. The method for producing a plastic molded circuit component according to claim 1, wherein an SPS resin is used as the resin that changes to an easily-platable resin by the laser irradiation.