JP2007027296A - Method of manufacturing molded circuit component - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To save resources by making a catalyst adhere only to the surface of plating deposit. <P>SOLUTION: (A) When a primary molded substrate 1 as a circuit forming body is molded by using a thermoplastic crystal material at a low mold temperature, it is quenched and crystallized at a low temperature. (B) The surfaces 1a and 1b are exposed on which a conductive layer of the primary molded substrate 1 is to be formed, and the other parts than them are covered with a circuit non-forming body 2 made of the same material as the material of the primary molded substrate 1, so as to form a secondary molded substrate 3. Molding temperature for injection-molding the circuit non-forming body 2 is sufficiently high to cause the circuit non-forming body to crystallize at high temperatures. (C) When the secondary molded body 3 is etched, its surface is roughened, and the surface of the circuit non-forming body 2 is not roughened. (D) A catalyst C is applied to the surface of the secondary molded substrate 3, and (E) conductive layers 4a and 4b are formed by electroless plating. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a molded circuit component in which a conductive layer having a predetermined circuit pattern made of a conductive material is formed on an electrically insulating primary molded substrate or a secondary molded substrate made of a thermoplastic crystal material.

Conventionally, a method for manufacturing a molded circuit component having a circuit pattern formed on its surface uses two thermoplastic resins consisting of a material mixed with an electroless plating catalyst and a material not mixed. Yes. The first example is that an amorphous thermoplastic compound containing a non-insulating catalyst for electroless metal plating is used to form one first insulating shape, and a crystalline thermoplastic resin compound is used. A second insulating shape is formed around the first insulating shape, and an integrated article having a predetermined region exposed from the first insulating shape surrounded by the second insulating shape on the surface is formed. There is one in which an electroless metal plating is performed on the exposed portion of (Patent Document 1). As a second example, there are a first material that is easily attached with metal plating made of plastic mixed with an electroless plating catalyst, and a second material that is hard to make metal plating made of plastic without mixing an electroless plating catalyst. Among the formed basic molded articles, there is one in which the surface of the first material is subjected to metal plating (Patent Document 2).
Japanese Patent No. 2592243 Japanese Patent No. 3004689

  The problem to be solved is that both of the above two conventional examples use a material in which a plating catalyst is mixed as a material on which electroless plating is performed. However, this catalyst is a rare metal such as palladium or gold, and mixing such an expensive catalyst is expensive in terms of cost. The catalyst deposits the plating and does not need to exist in the interior of the product. If it is on the surface to be plated, it is sufficient if necessary.

  Accordingly, an object of the present invention is to provide a method of manufacturing a molded circuit component that can save resources by attaching a catalyst only to a plating deposition surface.

  As a background of the development of the present invention, a thermoplastic crystal material, such as syndiotactic polystyrene resin (SPS), is injected into a molding die in a molten state at the time of injection molding, and in the process of cooling and solidifying, a low temperature die It begins with paying attention to the large difference in crystallinity rate between the case of solidification by rapid cooling and the case of low-speed solidification with a high-temperature mold. The higher the crystallinity of the thermoplastic crystal material, that is, the higher the chemical resistance in the highly crystallized (completely crystallized) region, and the stronger the chemical attack property. On the contrary, in the non-crystallized region to the low crystallized region, the chemical resistance is low and the chemical attack property is weak.

  The greatest feature of the present invention is that the above-mentioned properties of the thermoplastic crystal material are utilized to form a circuit when molding by twice molding while changing the mold temperature of the injection molding while using a similar material. The substrate on the body side is molded at a low temperature necessary for low crystallization, and the substrate on the non-circuit-formed body side is molded at a high temperature necessary for high crystallization. Therefore, the skin layer of the low-crystallized member is roughened by the etching process, but the skin layer of the highly crystallized member is not roughened. A circuit pattern is formed on the roughened surface by plating using a plastic electroless process. Since the same thermoplastic crystal material is used as described above, the interface between the circuit formed body and the circuit non-formed body is compatible, and the etching solution in the plating process does not enter the interface. Therefore, a highly reliable molded circuit component can be manufactured.

  A first feature of the method for producing a molded circuit component according to the present invention is that a thermoplastic crystal material is formed by injection molding to form a primary molded substrate (1) which is an electrically insulating and predetermined circuit formed body, Of the surface of the primary molded substrate, the surface portions (1a, 1b) on which the conductive layer of the predetermined circuit pattern is to be formed are exposed, and the other portions are covered with the electrically insulating circuit non-former (2). The circuit non-formed body is made of a thermoplastic crystal material similar to the material of the primary molded base, and the circuit non-formed body is integrated with the primary molded base by injection molding. A plastic including an etching step on a surface portion of the primary molding substrate (1) on which the conductive layers (4a, 4b) of the circuit pattern are formed; Conductive layer is formed of conductive material by electroless plating process The molding temperature of the primary molding substrate (1) is set as a molding temperature of the limit necessary for low crystallization of the skin layer of the primary molding substrate. The molding condition of the non-circuit formed body (2) is that the mold temperature is set to a high enough temperature to cause the skin layer of the non-circuit formed body to be highly crystallized.

  The thermoplastic crystal material includes polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyamide (PA), polyetherimide (PI), syndiotactic polystyrene (SPS), poniphenylene sulfide (PPS), It consists of at least one material selected from polypropylene (PP), polyethylene (PE), polyetheretherketone (PEEK), and polyoxymethylene (POM).

  The circuit non-former described above is made of a thermoplastic crystal material similar to the material of the primary molding substrate, and this same system is the compatibility between the circuit molded body and the primary molding substrate, It is for stronger integration.

  The second feature of the present invention is that a thermoplastic crystalline material is formed by injection molding to form a primary molded substrate (20) which is an electrically insulating and non-formed circuit having a predetermined shape, and among the surfaces of the primary molded substrate, An electrically insulating circuit forming body integrally formed with the primary molding substrate by injection-molding a thermoplastic crystal material similar to the material of the primary molding substrate in a portion where a conductive layer having a predetermined circuit pattern is to be formed (10) forming a secondary molded substrate (30), and etching the surface portion of the circuit formed body on which the conductive layer of the circuit pattern of the secondary molded substrate (30) is formed. Forming a conductive layer (40a, 40b, 40c) with a conductive material by a plastic electroless plating process including a step, and forming conditions of the primary molded substrate (20) that is the circuit non-former As the mold temperature of this primary molding substrate The quin layer is set at a sufficiently high temperature for high crystallization, and as a molding condition of the circuit forming body (10) of the secondary forming substrate (30), the mold temperature is set to be low for the skin layer of the circuit forming body. The temperature is set to the low temperature necessary for crystallization.

  A third feature is that, in the second feature, a through hole (20a) is formed in the primary molded substrate (20), and a conductive layer (40b) is formed on at least the upper and lower surfaces of the secondary molded substrate (30). 40c) is formed.

  As an effect of the present invention, it is possible to save resources because the catalyst is imparted only to the plating deposition surface, and the circuit formed body and the circuit non-formed body are integrally injection-molded with a similar thermoplastic crystal material, The interface has good compatibility, and the etching solution and the plating solution do not enter between each other, so that reliable quality can be obtained. Further, since no catalyst is present at the interface between the circuit forming body and the circuit non-forming body, and no catalyst is mixed inside the circuit forming body or the circuit non-forming body, high electrical insulation is ensured. A circuit pattern is formed on the circuit formed body roughened by the etching process by metal plating, and this metal plating strongly adheres to the roughened surface by an anchor effect (throwing effect). Further, since the skin layer on the non-circuit surface is highly crystallized, it is not roughened in the etching process, and is hydrophobic and moisture hardly adheres, so that high reliability can be ensured.

Hereinafter, a first embodiment of the present invention will be described with reference to FIG.
As shown in FIG. 1A, a primary molded substrate 1 which is a circuit forming body having a predetermined shape and an electric insulation is formed by injection molding of a thermoplastic crystal material. Examples of the thermoplastic crystal material include polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyamide (PA), polyetherimide (PI), syndiotactic polystyrene (SPS), poniphenylene sulfide (PPS), polypropylene ( It is made of at least one material appropriately selected from PP), polyethylene (PE), polyetheretherketone (PEEK), and polyoxymethylene (POM). In order to increase the rigidity of the thermoplastic crystal material, a filler such as glass fiber, potassium titanate whisker, strontium titanate whisker, or barium titanate whisker may be included. Further, butadiene and various elastomer components may be filled in order to improve impact resistance.

  As a molding condition in the case of injection molding the primary molding substrate 1, it is necessary to set the mold temperature to a low temperature necessary for low crystallization of the skin layer of the primary molding substrate.

As thermoplastic crystal resin, for example, syndiotactic polystyrene (SPS) resin, and as a specific example, “XAREC # S131” (product of Idemitsu Kosan Co., Ltd.) is used as a material for primary molding substrate 1. Particularly, the low temperature necessary for low crystallization of the skin layer of the primary molded substrate is as follows.
Mold temperature 40 ℃ ~ 60 ℃
Cylinder temperature 280 ° C ~ 290 ° C
Injection pressure 1000kg / cm ²
Therefore, the material “XAREC # S131” of the primary molded body 1 is rapidly cooled because the mold temperature is as low as 40 ° C. to 60 ° C. from the melted state, and the crystallization of the skin layer of the primary molded body is delayed. Low crystallization. This low crystallization includes those that are hardly crystallized, that is, those that are nearly non-crystallized.

  Next, as shown in FIG. 1B, among the surface of the primary molded substrate 1, a surface portion 1a on which a conductive layer having a predetermined circuit pattern (see 4a and 4b in FIG. 1E) is to be formed. The circuit non-formed body is made of the thermoplastic crystal material similar to the material of the primary molding substrate 1 by injection molding so that 1b is exposed and the other part is covered with the electrically insulating circuit non-formed body 2. The secondary molded base 3 is formed integrally with the primary molded base. The material of the circuit non-formed body 2 is the same as the material of the primary molded base 1. The material of the circuit non-formed body has compatibility with the primary molded base, and therefore, the primary molded body that is the circuit formed body and This means that the non-circuit-formed body 2 is integrated and the secondary molded base 3 as a whole is easily integrated.

  The molding conditions in the case of injection molding of the non-circuit formed body 2 of the constituent parts of the secondary molded base 3, especially the mold temperature, are set to a high enough temperature to make the skin layer of the non-circuit formed body highly crystallized. It is necessary.

Molding in the case of using, for example, syndiotactic polystyrene (SPS) resin as the thermoplastic crystal resin, and “XAREC # S120” (product of Idemitsu Kosan Co., Ltd.) as a material of the circuit non-former 2 as a specific example. Regarding the conditions, particularly the temperature of the mold, the high temperature sufficient to highly crystallize the skin layer of the non-circuit-formed body 2 is as follows.
Mold temperature 140 ℃ ~ 160 ℃
Cylinder temperature 280 ° C ~ 290 ° C
Injection pressure 800kg / cm ²
As described above, since the mold temperature at the time of injection molding of the non-circuit-formed body 2 is as high as 140 ° C. to 160 ° C., it takes time to cool the melted “XAREC # S120”. Is promoted, and the skin layer of the non-circuit formed body is highly crystallized.

  Next, a process of forming a conductive layer with a conductive material by a plastic electroless plating process on the surface portions 1a and 1b where the conductive layer of the circuit pattern of the primary molded substrate 1 is formed will be described.

First, as shown in FIG. 1C, the secondary molded body 3 is degreased and its surface is roughened, that is, etched. As an example of this etching process, a chromium sulfuric acid solution is set to a predetermined concentration, for example, hexavalent chromium CrO ₃ is 430 g / l, sulfuric acid H ₂ SO ₄ (98%) is 320 cc / l, and heated to a predetermined temperature, for example, 65 ° C. The secondary molded body 3 is immersed for a predetermined time, for example, 30 minutes. By this etching process, the surface portions 1a and 1b of the primary molded body 1 exposed from the circuit non-formed body 2 are low-crystallized and etched to roughen the surface, but the surface of the circuit non-formed body 2 is high. Since it is crystallized, it does not roughen.

  Next, as shown in FIG. 1D, a catalyst C made of palladium, gold, or the like is applied to the surface of the secondary molded base 3 including the surface portions 1a and 1b of the primary molded base 1. This catalyst application treatment is a known one. For example, after the secondary molded substrate 3 is immersed in a mixed catalyst solution of tin and palladium, it is activated with an acid such as hydrochloric acid or sulfuric acid to deposit palladium on the surface. . Alternatively, a relatively strong reducing agent such as stannous chloride is adsorbed on the surface and immersed in a catalyst solution containing a noble metal ion such as gold to deposit gold on the surface. What is necessary is just to immerse the temperature of this catalyst solution at 15-23 degreeC for 5 minutes.

  Through the plastic electroless plating pretreatment process as described above, as shown in FIG. 1 (E), the conductive layers 4a and 4b of the circuit pattern are formed on the surface portions 1a and 1b of the primary molded base 1 by electroless plating. Is formed.

Next, a second embodiment will be described with reference to FIG.
As shown in FIG. 2A, first, a primary molded substrate 20 which is an electrically insulating and non-circuit shaped body having a predetermined shape is formed by injection molding of a thermoplastic crystal material. The primary molded base 20 is formed with a through hole 20a penetrating vertically. This thermoplastic crystal material has already been described in the first embodiment.
As a molding condition of the primary molded substrate 20 which is a non-circuited body, it is necessary that the mold temperature is set to a high enough temperature to cause the skin layer of the primary molded substrate to be highly crystallized.

As a thermoplastic crystal resin, for example, syndiotactic polystyrene (SPS) resin, and as a specific example, “XAREC # S120” (product of Idemitsu Kosan Co., Ltd.) is used as a material for the primary molded substrate 20 which is a circuit non-former. Regarding the molding conditions when used, particularly the temperature of the mold, the high temperature sufficient to highly crystallize the skin layer of the primary molding substrate 20 is as follows.
Mold temperature 140 ℃ ~ 160 ℃
Cylinder temperature 280 ° C ~ 290 ° C
Injection pressure 800kg / cm ²
As described above, since the mold temperature at the time of injection molding the primary molded base body 20 which is a non-circuited body is as high as 140 ° C. to 160 ° C., it takes time to cool the molten “XAREC # S120”. Therefore, crystallization is promoted, and the skin layer of the non-circuit formed body is highly crystallized.

  Next, as shown in FIG. 2B, a portion of the surface of the primary molded base 20 where a conductive layer having a predetermined circuit pattern (see 40a, 40b, and 40c in FIG. 2E) is to be formed. Then, a thermoplastic crystal material similar to the material of the primary molding substrate 20 is injection-molded to form a secondary molding substrate 30 including the electrically insulating circuit forming body 10 integrally with the primary molding substrate. Further, when the circuit formed body 10 is injection-molded, the thermoplastic crystal material is distributed to the upper and lower surfaces through the through-holes 20a, and the circuit formed body 10 is exposed at two locations on the upper surface of the secondary molded substrate 30 and at one location on the lower surface. ing.

  As a molding condition of the circuit-formed body 10 of the secondary molded body 30, the mold temperature is set to a low temperature necessary for low crystallization of the skin layer of the circuit-formed body.

As thermoplastic crystal resin, for example, syndiotactic polystyrene (SPS) resin, and as a specific example, “XAREC # S131” (product of Idemitsu Kosan Co., Ltd.) is used as a material for circuit forming body 10. Particularly, the low temperature necessary for low crystallization of the skin layer of this circuit formed body is as follows.
Mold temperature 40 ℃ ~ 60 ℃
Cylinder temperature 280 ° C ~ 290 ° C
Injection pressure 1000kg / cm ²
Therefore, “XAREC # S131” in the molten state of the material of the circuit formed body 10 is rapidly cooled because the mold temperature is as low as 40 ° C. to 60 ° C., and the crystallization of the skin layer of this primary molded body is delayed. Low crystallization. This low crystallization includes those that are hardly crystallized, that is, those that are nearly non-crystallized.

  Next, a conductive layer is formed of a conductive material by a plastic electroless plating process including an etching step on the surface portions 10a, 10b, and 10c of the circuit forming body 10 on which the conductive layer of the circuit pattern of the secondary molded body 30 is formed. The process will be described. The surface portions 10b and 10c are connected by “XAREC # S131” filled in the through hole 20a.

First, as shown in FIG. 2C, the secondary molded substrate 30 is degreased and its surface is roughened, that is, etched. As an example of this etching process, a chromium sulfuric acid solution is set to a predetermined concentration, for example, hexavalent chromium CrO ₃ is 430 g / l, sulfuric acid H ₂ SO ₄ (98%) is 320 cc / l, and heated to a predetermined temperature, for example, 65 ° C. The secondary molding substrate 30 is immersed for a predetermined time, for example, 30 minutes. By this etching process, the surface portions 10a, 10b, and 10c of the circuit formed body 10 that are exposed from the primary molded base body 20 that is a circuit non-formed body are low crystallized, so that they are etched and roughened. Since the surface of the primary molded substrate 20 as a formed body is highly crystallized, it is not roughened.

  Next, as shown in FIG. 2D, a catalyst Ca made of palladium, gold, or the like is applied to the surface of the secondary molded substrate 30 including the surface portions 10a, 10b, and 10c of the circuit formed body 10. This catalyst application treatment is a known one. For example, after the secondary molding substrate 30 is immersed in a mixed catalyst solution of tin and palladium, the catalyst is activated with an acid such as hydrochloric acid or sulfuric acid to deposit palladium on the surface. . Alternatively, a relatively strong reducing agent such as stannous chloride is adsorbed on the surface and immersed in a catalyst solution containing a noble metal ion such as gold to deposit gold on the surface. What is necessary is just to immerse the temperature of this catalyst solution at 15-23 degreeC for 5 minutes.

  After the plastic electroless plating pretreatment process as described above, as shown in FIG. 2E, the surface portions 10a, 10b, and 10c of the circuit formed body 10 are formed on the surface portions 10a, 10b, and 10c of the circuit pattern 10 by electroless plating. , 40b, 40c are formed.

  In this embodiment, two or more conductive layers 40 a, 40 b, 40 c, that is, conductive layers having a circuit pattern are formed on the surface of the secondary molded substrate 30, and the flow path connecting the conductive layers is formed on the primary molded substrate 20. It can be provided inside. Even if the conductive layers 40b and 40c are connected by the circuit forming body 10, since the circuit forming body is electrically insulating, there is no short circuit. Therefore, the thermoplastic crystal material can be distributed through the through-holes 20a to form circuit patterns not only on the surface of the secondary molded substrate 30, but also on the back surface and side surfaces.

  As an application example of the invention, the present invention can be used for three-dimensional electronic circuit or technology development for element formation of a built-in antenna of a mobile phone.

The manufacturing process of 1st Embodiment is shown, (A) is the shaping | molding process of the primary shaping | molding base | substrate which is a circuit formation body, (B) is a shaping | molding process of a secondary shaping | molding base | substrate, (C) is an etching process, (D) is a catalyst providing step, and (E) is a conductive layer forming step. The manufacturing process of 2nd Embodiment is shown, (A) is the shaping | molding process of the primary shaping | molding base | substrate which is a circuit non-formation body, (B) is a shaping | molding process of a secondary shaping | molding base | substrate, (C) is an etching process. , (D) is a catalyst application step, and (E) is a conductive layer forming step.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Primary shaping | molding base | substrate 1a, 1b surface part 2 Circuit non-formation body 3 Secondary shaping | molding base | substrate 4a, 4b Conductive layer 20 Primary shaping | molding base | substrate 20a through-hole 10 Circuit formation body 30 Secondary shaping | molding which is a circuit non-formation body Base 40a, 40b, 40c Conductive layer

Claims (3)

Forming a primary molded substrate (1), which is an electrically insulating and predetermined-shaped circuit formed body by injection molding of a thermoplastic crystal material; and
Of the surface of the primary molding substrate, the surface portions (1a, 1b) on which the conductive layer having a predetermined circuit pattern is to be formed are exposed, and the other portions are covered with an electrically insulating circuit non-former (2). The non-circuit formed body is made of a thermoplastic crystal material similar to the material of the primary molded base, and the non-circuit formed body is integrated with the primary molded base by injection molding. Forming a secondary molded substrate (3) formed by
Forming a conductive layer with a conductive material by a plastic electroless plating process including an etching step on a surface portion of the primary molded substrate (1) where the conductive layer (4a, 4b) of the circuit pattern is formed. And
As a molding condition of the primary molded substrate (1), the mold temperature is set to a low temperature necessary for low crystallization of the skin layer of the primary molded substrate,
A method for producing a molded circuit component, characterized in that, as a molding condition of the non-circuit-formed body (2), the mold temperature is set to a high enough temperature to cause the skin layer of the non-circuit-formed body to be highly crystallized. . Forming a primary molded substrate (20), which is an electrically insulating and non-circuit formed body having a predetermined shape, by injection molding a thermoplastic crystal material;
A thermoplastic crystal material similar to the material of the primary molding substrate is injection-molded on a portion of the surface of the primary molding substrate where a conductive layer having a predetermined circuit pattern is to be formed. Forming a secondary molded substrate (30) formed by forming an electrically insulating circuit forming body (10) on
A conductive layer (40a, 40b, 40c) is formed of a conductive material on a surface portion of the circuit-formed body on which the conductive layer of the circuit pattern of the secondary molded substrate (30) is formed by a plastic electroless plating process including an etching process. Forming a step),
As a molding condition of the primary molded substrate (20) that is the non-circuit-formed body, the mold temperature is set to a high enough temperature to highly crystallize the skin layer of the primary molded substrate,
The molding temperature of the circuit molded body (10) of the secondary molded substrate (30) is characterized in that the mold temperature is set to a low temperature necessary for low crystallization of the skin layer of the circuit molded body. A method of manufacturing a molded circuit component.   In Claim 2, the said primary shaping | molding base | substrate (20) has the through-hole (20a), and the electroconductive layer (40b, 40c) is formed in at least the upper and lower surfaces of the said secondary shaping | molding base | substrate (30). A method for producing a molded circuit component, comprising:

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