JPH0259870B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a surface treatment method as a pretreatment method for metal plating the surface of a heat-resistant resin molded article. [Prior art] Conventionally, the surface of polyphenylene sulfide resin (hereinafter referred to as PPS resin), which is a crystalline resin, is mechanically roughened as a pretreatment method when metal plating is applied to the surface of the molded product. How to
(see Japanese Patent Application Laid-open No. 183473/1983), and a method of roughening a PPS resin molded product containing an inorganic filler using a good solvent for PPS (see Japanese Patent Application Laid-Open No. 183473/1983), also by Friedel Crafts. A method of roughening with a catalyst (see JP-A-61-250175), a method of pre-treatment with a laser beam (JP-A-61-250175),
It has been proposed that pretreatment under strict conditions such as (see Publication No. 127867) is an essential condition for improving the adhesion of the plating formed by the subsequent metal plating treatment. On the other hand, as a pretreatment method for metal plating the surface of an amorphous resin molded article, it is known that pre-etching with an organic polar solvent is followed by etching with chromic acid. Furthermore, as a method to improve the adhesion of metal plating, a multi-stage pre-etching process (Japanese Unexamined Patent Application Publication No. 1986-
252691) has been proposed. [Problems to be Solved by the Invention] However, in general, in a molded article made of a resin composition in which an inorganic filler is included in a blend resin of an amorphous resin and a crystalline resin, it is difficult to plate the surface with metal. When the surface roughening treatment method described above is used as a pretreatment method, there is a tendency that the adhesion of metal plating is not sufficient. That is, even if a method for roughening the surface of a PPS resin molded product containing an inorganic filler is employed, the adhesion of metal plating cannot be satisfied. On the other hand, even if a method for roughening the surface of a resin molded article made of an amorphous resin is employed, there is almost no effect of roughening the surface and the plating adhesion is insufficient. Therefore, aromatic polythioethersulfone copolymer as an amorphous resin and crystalline resin
A resin molded product made of a resin composition containing an inorganic filler in a blended resin with PPS resin has improved heat resistance compared to the former single resin molded product, and is less brittle compared to the latter single resin molded product. It has the advantage of being improved. Therefore, it is extremely useful to apply such resin molded products to electronic components such as printed wiring boards. in general,
When a resin molded product is applied to a printed wiring board or the like, the surface of the molded product is appropriately roughened, and then a wiring pattern is formed by metal plating, for example, electroless plating. However, as mentioned above, there is no surface roughening treatment method using conventional techniques for a resin molded product made of a resin composition containing an inorganic filler in a blend resin of an aromatic polythioethersulfone copolymer and a PPS resin. There is a problem in that it cannot be an effective means and does not satisfy the adhesion of metal plating. The present invention has been made in view of these problems, and is made by molding a composition of an aromatic polythioethersulfone copolymer and a PPS resin, or a resin composition in which the composition contains an inorganic filler. The object of the present invention is to provide a new surface treatment method for metal plating the surface of a resin molded product. [Means for Solving the Problems] That is, the present invention provides a method for pre-treating the surface of a heat-resistant resin molded product for metal plating, in which the resin molded product is made of an aromatic polythioethersulfone copolymer and a polyphenylene sulfone copolymer. molded from a composition made of an ide resin or a resin composition containing 250% by weight or less of an inorganic filler based on the composition,
A heat-resistant resin molded product characterized in that the surface of the resin molded product is roughened by chemical treatment, and then treated with an acid treatment with a chromic acid mixed acid solution and with a hydrofluoric acid or ammonium hydrogen fluoride solution. The present invention provides a surface treatment method. In the present invention, the aromatic polythioethersulfone copolymer is a homopolymer of polymerized units represented by the following formula [] or a random or block-like copolymer of the same and other polymerized units, particularly the following: A copolymer (aromatic polyether sulfone/polythioether sulfone copolymer) with a polymer unit represented by formula [] is preferred. (However, Ar in the formula is

【formula】

【formula】

Selected from [Formula]; R ¹ to ^{R 7} represent hydrogen or a hydrocarbon group having 1 to 8 carbon atoms, and may be the same or different from each other; a to e are 0 to 4, f and g are 0 An integer of ~3, which may be the same or different; Y is a single bond -O
−, −S−, −SO ₂ −,

【formula】

[Formula]; R represents hydrogen or a hydrocarbon group having 1 to 6 carbon atoms). Therefore, in the aromatic polythioethersulfone copolymer represented by the above formula, the ratio of the number n of polymerized units represented by the formula [] to the number m of the polymerized units represented by the formula [] is m:n= 1:20～
A ratio of 20:1 is preferred. Furthermore, in view of the properties as a copolymer, moldability, etc., preferably m:n=1:10 to 15:1, particularly preferably m:n
= 1:4 to 10:1 copolymer. Furthermore, the degree of polymerization of the aromatic polythioethersulfone copolymer is determined at 30°C for a solution with a concentration of 0.5 g/dl using phenol/1,1,2,2-tetrachloroethane = 3/2 (weight ratio) as a solvent. Logarithmic viscosity (η _ioh ) measured at
When expressed as 0.1 to 1.5, it is usually preferable. More preferably, the logarithmic viscosity (η _ioh ) is
0.1 to 1.3, particularly preferably 0.1 to 1.0
belongs to. The method for producing the above copolymer is disclosed in Japanese Patent Application Laid-Open No. 61-72020.
No. 61-76523 and JP-A-61
It can be obtained by the method disclosed in Japanese Patent No.-168629. On the other hand, the PPS resin blended with the above polymer has the general formula

It is preferable that the structural unit represented by the formula is 70 mol% or more, and the amount thereof is 70 mol%.
If it is less than that, it is difficult to obtain a composition with excellent properties.
Polymerization methods for this polymer include a method in which p-dichlorobenzene is polymerized in the presence of sulfur and sodium carbonate, and a method in which p-dichlorobenzene is polymerized in the presence of sodium sulfide and sodium hydroxide or hydrogen sulfide and sodium hydroxide in a polar solvent. , self-condensation of p-chlorothiophenol, etc., but a suitable method is to react sodium sulfide with p-dichlorobenzene in an amide solvent such as N-methylpyrrolidone or dimethylacetamide, or a sulfonic solvent such as sulfolane. It is. At this time, in order to adjust the degree of polymerization, it is a preferable method to add an alkali metal salt of carboxylic acid or sulfonic acid, or to add an alkali hydroxide, an alkali metal carbonate, or an alkaline earth metal oxide. 30 mol% as copolymer component
If it is less than, it is a meta join (

[Formula]), or So-join (

[Formula]), ether bond (

[Formula]), sulfone bond (

[Formula]), biphenyl Join (

[Formula]), substituted Fe Nilsulfide bond (

[Formula] Here, R represents an alkyl group, a nitro group, a phenyl group, an alkoxy group, a carboxylic acid group, or a metal base of a carboxylic acid), a trifunctional bond (

[Formula]) may be contained as long as it does not significantly affect the crystallinity of the polymer, but preferably the copolymer component should be 10 mol% or less. The proportions of the above aromatic polythioethersulfone copolymer and PPS resin are 5 to 80 parts by weight of the aromatic polythioethersulfone copolymer, PPS
20 to 95 parts by weight of resin. Therefore, in view of the balance between the heat resistance of the resin molded product and the adhesion of metal plating to its surface, it is preferable that the former copolymer be in the range of 10 to 70 parts by weight and the latter resin be in the range of 30 to 90 parts by weight. It is. In the present invention, the resin composition may contain an inorganic filler in the above resin. The amount of inorganic filler contained herein is 250% by weight or less, preferably 20 to 100% by weight, based on the composition. Examples of such inorganic fillers include glass fibers, carbon fibers, potassium titanate, asbestos, silicon carbide, ceramic fibers, metal fibers, fibrous reinforcing agents such as silicon nitride, barium sulfate, calcium sulfate, kaolin, clay, pyrophyllant, and bentonite. , sericite, zeolite, mica, mica, nephelinsinite, talc, atalbazyite, wollastonite, PMF, ferrite, calcium silicate, calcium carbonate, magnesium carbonate, dolomite, antimony trioxide, zinc oxide,
Inorganic fillers such as titanium oxide, magnesium oxide, iron oxide, molybdenum dioxide, graphite, gypsum, glass beads, gallus balloons, quartz powder, etc. Considering that it is a pretreatment for metal plating, fibrous reinforcing agents, especially Preferably it is glass fiber. Moreover, a fibrous reinforcing agent and the above-mentioned inorganic filler in granular or powder form can also be used together. In such an inorganic filler, the particle size is the average particle size.
The diameter is 0.1 to 10μ, more preferably 0.5 to 5μ. The resin composition in the present invention can be prepared by employing various known methods. For example, an aromatic polythioethersulfone copolymer and a PPS resin are further mixed with a desired inorganic filler, etc., and mixed in a mixer such as a V mixer, tumbler, or Henschel mixer, and then After melt-mixing and extruding into strands using an extruder at a temperature of 290-400℃,
It is cooled and made into a pellet-like material using a pelletizer. The pellets thus obtained are molded into a desired shape, such as a film, using a commonly used thermoplastic resin molding machine, such as an injection molding machine, a compression molding machine, an injection compression molding machine, or an extrusion molding machine. It is molded into molded products such as plates. A surface treatment method as a pretreatment for metal plating the surface of the resin molded product thus obtained will be described. The resin composition of the present invention has excellent compatibility between the blended resins, so unlike resin compositions made of amorphous resin and PPS resin that exhibit general incompatibility, the chemical resistance of the molded product is Gender shows a peculiar tendency. In other words, in a molded article made of an incompatible resin composition, since the amorphous resin and PPS resin are distributed macroscopically on the surface, it is not resistant to chemicals that corrode PPS resin. The crystalline resin is too eroded and good adhesion of metal plating cannot be obtained. On the other hand, since PPS resin is hardly corroded by chemicals that corrode amorphous resins, good adhesion of metal plating cannot be obtained as well. However, the surface of the molded product made of the blend resin composition of the aromatic polythioethersulfone copolymer and PPS resin in the present invention has extremely high chemical resistance, and this is because the thin layer of PPS resin forms the surface layer. However, it is considered that the surface of the molded product is covered, and the lower layer of this thin layer has a structure similar to a microphase separation structure consisting of the aromatic polythioethersulfone copolymer and the PPS resin. It is presumed that it has become popular. Therefore, as a pretreatment method for metal plating, after removing the thin layer of PPS resin that forms on the surface of the molded product, molding is performed by etching the microscopically dispersed aromatic polythioethersulfone copolymer portion. It is possible to form a fine uneven structure on the surface of the product and improve the adhesion of metal plating. Two methods are considered for removing the thin layer of PPS resin: a physical method such as sandblasting, and a chemical method using chemicals, but when it comes to three-dimensional injection molded products, Since the latter method is more preferred, also in the surface treatment method of the present invention, chemical treatment is first performed. As a chemical treatment method, a resin molded article is immersed in a mixture of one or more selected from anhydrous aluminum chloride, ferric chloride, antimony pentachloride, and tellurium dichloride and an organic solvent. The organic solvent used is an aromatic organic solvent such as benzene, toluene, xylene, or chlorobenzene, and may be one type or a mixed solvent of two or more thereof.
The amount of the organic solvent is selected from the range of 1 part by weight to 200 parts by weight per 1 part by weight of the above-mentioned anhydrous aluminum chloride or tellurium dichloride. The solution temperature as a condition in chemical processing is 20-100
℃ is sufficient, but more preferably 30 to 90℃,
The soaking time may be 30 seconds to 10 minutes. Through such chemical treatment, the surface of the resin molded product is exposed with a micro-structured surface of the aromatic polythioethersulfone copolymer and PPS resin, and only the copolymer portion on this surface is further etched. By doing so, it is possible to obtain a surface with an extremely high density uneven structure, and therefore the adhesion of metal plating can be improved. In the present invention, the above-mentioned etching is performed by acid treatment using a chromic acid mixed acid solution, but the above-mentioned chemical treatment is followed by N-methyl -3-30% in an organic polar solvent such as 2-pyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide at 20-100℃
This is done after immersion. The chromic acid mixed acid solution used for acid treatment consists of an aqueous solution of chromic acid anhydride, sulfuric acid, and phosphoric acid.
This is done by immersion. Subsequently, a further treatment with hydrofluoric acid or ammonium hydrogen fluoride solution is performed. This hydrofluoric acid or ammonium hydrogen fluoride solution has a concentration of 5 to 50% by weight.
It is preferable that Hydrofluoric acid and ammonium hydrogen fluoride solution may be used in combination, and this is particularly suitable when the resin molded article contains glass fibers and, for example, glass beads as an inorganic filler. Metal plating is performed on the surface of a resin molded product whose surface has been roughened by the above-mentioned surface treatment method. After processing such as accelerating and accelerating, electroless plating and/or electroplating is performed. The combined use of electroless plating and electroplating can provide a surface-metallized resin molded product with excellent adhesion. In the present invention, a resin molded product is produced by using a particulate or powdery inorganic filler in addition to a fibrous material such as glass fiber as an inorganic filler in a resin composition containing an inorganic filler. Although it is possible to improve the mechanical properties of resin molded products made from resin compositions that do not contain such inorganic fillers, sufficiently excellent metal plating can be achieved by pre-treating the surface of the resin molded products. Indicates adhesion. Thus, the resin molded product treated by the surface treatment method of the present invention is metal-plated to provide a printed wiring board with excellent metal plating adhesion, hygroscopicity, and electrical properties. Next, the present invention will be explained in more detail with reference to examples, but it goes without saying that the present invention is not limited only to these examples. [Example] Example 1 Copolymer having polymer units represented by the following two formulas (ratio of the number of each polymer unit 1:1) [η _ioh = 0.55 (phenol/1,1,2,2-tetrachloroethane = 3/2 weight ratio, concentration 0.5 g/dl,
(measured at 30°C)] 20 parts of aromatic polyethersulfone/polythioethersulfone copolymer [A], (parts by weight,
(same below), PPS resin (“Ryton P-4”: manufactured by Phillips Petroleum Co., Ltd.) 80 parts, glass fiber (“03-JA-404”: manufactured by Asahi Fiberglass Co., Ltd.) 67
The mixture was uniformly mixed using a V-type mixer, and then melt-extruded using a twin-screw extruder in opposite directions at a cylinder temperature of 320°C to obtain pellets. The pellets are then molded into cylinders using an injection molding machine.
It was molded under the conditions of 320°C, injection pressure of 1000 Kg/cm ² and mold temperature of 130°C to obtain a flat test piece of 10 x 10 cm square and 3 mm thick. The thus obtained test piece was sequentially treated according to the following surface treatment method, and then copper plating was applied. Degreasing treatment: “OPC-250 Cleaner M” as a degreaser
(Manufactured by Okuno Pharmaceutical Co., Ltd.) 50g/solution is heated to 60°C, and the test piece is immersed for 4 minutes while stirring. Chemical treatment 13.6g of anhydrous aluminum chloride and 1700g of toluene
The test piece was suspended in water, heated to 80°C, and immersed for 4 minutes while stirring. Thereafter, the sample is subjected to ultrasonic cleaning using methanol, dried, and then immersed in an N-methyl-2-pyrrolidone bath at 80 DEG C. for 10 minutes with stirring, followed by thorough washing. Acid treatment Chromic anhydride 3, sulfuric acid 56, phosphoric acid 10.5, water
30.5 (each weight%) chromic acid mixed acid solution was heated to 75℃, the test piece was immersed for 10 minutes, thoroughly washed with water, and then immersed in a hydrofluoric acid solution with a concentration of 5% by weight for 10 minutes. , rinse thoroughly with water. Electroless copper plating treatment (1) Pre-dipping treatment “OPC-” is used as a pre-dipping agent.
SALM” (manufactured by Okuno Pharmaceutical Co., Ltd.) 260g/solution
After soaking the test piece at 25°C for 2 minutes, wash it with water. −(2) Catalyzing treatment “OPC-catalyst M” (manufactured by Okuno Pharmaceutical Co., Ltd.) 260g/ and “OPC-80 Catalyst M” (manufactured by Okuno Pharmaceutical Co., Ltd.) as catalysts
After soaking the test piece at 25℃ for 6 minutes,
Wash with water. −(3) Acceleration processing As an accelerator, use “OPC-555 Accelerator M” manufactured by Okuno Pharmaceutical Co., Ltd.) 28 to 100 ml/solution.
After soaking the test piece at ℃ for 8 minutes, wash it with water. -(4) Copper plating treatment As an electroless copper plating solution, mix each solution of "OPC-750 electroless copper plating solution M" A, B, and C (manufactured by Okuno Pharmaceutical Co., Ltd.) at a ratio of 100 ml, 100 ml, and 2 ml. The total volume was adjusted to 1 with ion-exchanged water, and the test piece was immersed in a plating bath at a temperature of 22°C for 10 minutes under air bubbling to perform electroless copper plating. Electrolytic copper plating treatment Prepare an electroplating bath by adjusting the total volume of 75 g of copper sulfate pentahydrate, 190 g of sulfuric acid, and 100 ml of "Totsu Pluchina H-300" (manufactured by Okuno Pharmaceutical Co., Ltd.) to 1 with ion-exchanged water. ^2. Keep the test piece at 24℃ and perform electrolytic copper plating under air bubbling for 70 minutes. A copper-plated plate with a 35-μ thick copper coating formed on the surface of the test piece was obtained by sequentially carrying out the above surface treatment ~ and plating treatment ~. The characteristics of this copper-plated board include the measurement of the 90°C peel strength of the copper coating and the heat distortion temperature (hereinafter referred to as
HDT) was measured and the results are shown in Table 1. Example 2 Aromatic polyethersulfone/polythioethersulfone copolymer [A] similar to Example 1
A test piece was obtained in the same manner as in Example 1 except that 40 parts of PPS resin and 60 parts of PPS resin were used, and a copper-plated plate was further subjected to surface treatment and copper plating treatment. The properties of this copper-plated plate were measured in the same manner as in Example 1, and the results are shown in Table 1. Example 3 The inorganic filler in Example 1 was replaced with glass fiber 50
A test piece was obtained in the same manner as in Example 1 except that 17 parts of calcium carbonate (average particle size 1 μm) was used, and a copper-plated plate was obtained by surface treatment and copper plating treatment. The properties of this copper plated plate were measured and the results are shown in Table 1. Examples 4 to 6 The aromatic polyether sulfone/polythioether sulfone copolymer [A] in Examples 1 to 3 was converted into a copolymer [B] having polymer units represented by the following two formulas (each polymer unit (number ratio 1:1) (η _ioh =0.56) Test pieces were obtained in the same manner as in Examples 1 to 3, except that the test pieces were subjected to surface treatment and copper plating treatment to obtain copper-plated plates. The properties of this copper plated plate were measured and the results are shown in Table 1. Example 7 In Example 4, aromatic polyethersulfone/polythioethersulfone copolymer [B]
A test piece was obtained in the same manner as in Example 1, except that 60 parts of PPS resin and 40 parts of PPS resin were used, and a copper-plated plate was further subjected to surface treatment and copper plating treatment. The properties of this copper plated plate were measured and the results are shown in Table 1. [Comparative Example] Comparative Example 1 In place of the aromatic polyethersulfone/polythioethersulfone copolymer [A] as the aromatic polythioethersulfone copolymer in Example 1, commercially available polyethersulfone (“VICTREX PES200P ”, η _ioh 0.55; phenol/1,1,2,2-tetrachloroethane = 3/
A test piece was obtained in the same manner as in Example 1, except that the test piece was used (measured at 30° C., 0.5 g/dl, and a weight ratio of 0.5 g/dl), and was further subjected to surface treatment and copper plating treatment to obtain a copper-plated plate.
The properties of this copper-plated plate were measured in the same manner as in Example 1, and the results are shown in Table 1. Comparative Example 2 A test piece was plated with copper in the same manner as in Example 1, except that no chemical treatment was performed in the surface treatment method of the test piece in Example 1. The properties of this copper plated plate were measured and the results are shown in Table 1. Comparative Example 3 In the surface treatment method of the test piece in Example 3, immersion in the N-methyl-2-pyrrolidone bath for chemical treatment was not performed, and 36 wt% hydrochloric acid was added instead of the chromic acid mixed acid solution for oxidation treatment. The test piece was copper plated in the same manner as in Example 3, except that it was immersed in water for 5 minutes. The properties of this copper plated plate were measured and the results are shown in Table 1. Comparative Example 4 A test piece was plated with copper in the same manner as in Example 1, except that the test piece was not immersed in a hydrofluoric acid solution for acid treatment in the method for surface treatment of the test piece in Example 1. The properties of this copper plated plate were measured and the results are shown in Table 1.

[Table] [Effects of the Invention] The surface treatment method of the present invention particularly applies to a resin composition containing a blend resin of an aromatic polythioethersulfone copolymer and a PPS resin or an inorganic filler as a heat-resistant resin. The effect of forming a metal plating having extremely excellent adhesion on the surface of a resin molded article is recognized. Therefore, in addition to the heat resistance properties of the resin, it also has the effect of providing electronic components, such as printed wiring boards, that have excellent mechanical properties, water absorption properties, electrical properties, and the like.

Claims (1)

[Scope of Claims] 1. In a method for pre-treating the surface of a heat-resistant resin molded article for metal plating, the resin molded article is made of a composition comprising an aromatic polythioether sulfone copolymer and a polyphenylene sulfide resin or a polyphenylene sulfide resin. It is molded from a resin composition containing 250% by weight or less of an inorganic filler based on the composition, and the surface of the resin molded product is roughened by chemical treatment, and then acidified with a chromic acid mixed acid solution. 1. A method for surface treatment of a heat-resistant resin molded article, which comprises treating with hydrofluoric acid or ammonium hydrogen fluoride solution. 2. A patent claim in which the ratio of the aromatic polythioethersulfone copolymer to the polyphenylene sulfide resin is 5 to 80 parts by weight of the aromatic polythioethersulfone copolymer and 95 to 20 parts by weight of the polyphenylene sulfide resin. The surface treatment method according to item 1. 3. After chemical treatment with a mixture of one or more selected from anhydrous aluminum chloride, anhydrous ferric chloride, antimony pentachloride, and tellurium dichloride and an organic solvent, the material is immersed in an organic polar solvent. A surface treatment method according to claim 1, wherein the surface treatment method is performed as described in claim 1.