KR810001328B1 - Method for preparation of a plated product - Google Patents

Abstract

A method is given for the direct electroplating of plastics without a previous electroless plating procedure. In 1 example a mixture of 100 parts ABS and 15 parts c black (surface area 1000 m2/g) was blended for 12 min and then this mass of a resistance of 17Ωcm was formed into a flat plate. 70 × 140 × 2 mm. After degreasing this plate was etched in Cr O3-H2SO4 and directly electroplated with Cu. The Cu bath contained CuSO4 and H2SO4 (concentrated) 50 g/L and was used at an initial current density of 1 A/dm2, this being increased to 3.5 A/dm2.

Description

Manufacturing method of plated product

The present invention relates to a new method for the production of plated products. More specifically, the present invention relates to a manufacturing method for obtaining a plated product made of a composition of a thermoplastic resin and carbon black.

Until now, synthetic resins have been used as raw materials for plating products in various fields because of their good molding capacity and light weight.

In particular, copolymers composed of vinyl cyanide, aromatics, vinyl compounds and conjugated diene rubbers have been widely used as synthetic resin materials for plating because of their excellent appearance and performance.

However, since these resins are electrically conductive, they cannot be directly electroplated and must be made of an electrically conductive material before electroplating. Therefore, electroplating of synthetic resin molded products should be done after pretreatment. The pretreatment process is carried out through many steps as follows. Surface preparation, degreasing, corrosion, activation (or catalysis-activation) and chemical plating, that is, molded products of synthetic resins, must first be surface cleaned to remove grooves and blemishes on the surface of the molded product.

Molded products should be degreased to remove oil stains and deposits. The degreased product is then corroded and neutralized with a corrosive solution such as sulfuric acid-chromic acid.

Sensitive to the final product, for example treated with tin chloride solution and activated. For example, treatment with a palladium chloride solution.

Otherwise, this treatment may be achieved at once with a palladium chloride solution containing tin ions.

The final product is then chemically plated by conventional methods to coat copper, nickel and chromium.

As described above, electroplating of molded articles of synthetic resin according to conventional processes requires many steps for pretreatment. Many chemicals are used at these stages, and the resulting wastes cause serious pollution problems.

The inventors have found that, as a result of extensive research, at least one part of the pretreatment step can be omitted by the use of any kind of synthetic resin mixture, in particular molded articles of such components can omit the step of chemical plating in electroplating. there was.

The present invention is based on this finding.

It is therefore an object of the present invention to provide a molded article of a resin mixture which can be electroplated without prior chemical plating. Another object of the present invention is to provide a method for electroplating molded articles of the resin mixture without prior chemical plating. Another object is to provide a method for producing a molded electroplating product of a resin mixture without chemical plating.

The present invention comprises 100 parts by weight of a thermoplastic resin having at least one resin component or more, and an oil absorption amount of 200 ml / 100 g or more, and a surface area of 500 m 2 / g or more (when determined by the nitrogen absorption method) to 3 to 100 parts by weight of carbon black. The composition has a volume eigenvalue of 10 ³ Ω · cm or less.

As a thermoplastic resin, a copolymer of vinyl cyanide, an aromatic vinyl compound and a conjugated diene rubber, vinyl chloride resin, polystyrene resin, polyphenylene oxide resin, polycarbonate resin, polysulfone resin, polyester resin, polyacetal resin, poly Amide resin, polyalkylene resin (for example, polyethylene, polypropylene), methacryl resin, aromatic vinyl compound-vinyl cyanide resin, ethylene-vinyl acetate resin, etc. may be used alone or in combination of two or more.

Among these, acrylonitrile-styrene-conjugated diene rubbers (for example, polybutadiene, styrene-butadiene copolymers and acrylonitrile-butadiene copolymers) are preferable.

When using two or more kinds of thermoplastic resins, their coexistence should be considered. Examples of mixed resins showing good coexistence are as follows.

The mixed resin of polyphenylene oxite resin and polystyrene, the mixed resin of polyethylene and polypropylene may be used, and the copolymer of vinyl cyanide, aromatic vinyl and conjugated diene rubber may be mixed with other resins, but it may be used with this copolymer. One or two or more resins selected from vinyl chloride resin, polyphenylene oxad resin, polycarbonate resin, polysulfone resin, polyacetal resin, methacryl resin, aromatic vinyl-vinyl cyanide resin, etc. Mix with When two or more kinds of thermoplastic resins are used, their ratio is appropriately determined depending on the kind. For example, the ratio of the copolymer resin of vinyl cyanide-aromatic vinyl-conjugated diene rubber with other resins may be used with resins of 1:99 to 99: 1 by weight.

The carbon black used in the present invention should have an oil absorption of 200 ml / 100 g or more and a surface area of 500 m 2 / g or more.

Carbon black that does not meet the above range conditions cannot form a good quality electroplated film. The amount of the carbon black with respect to 100 parts by weight of the thermoplastic resin is 3 to 100 parts by weight, the amount of oil absorption 200ml / 100g or more and less than 3 parts by weight of the carbon black can not form the electrodeposited rupture film. Moreover, at 100 weight part or more, the physical property of a molded article falls remarkably, and it is not practical. Best is 8-25 parts by weight of carbon black.

The term used as the oil absorption amount above denotes the amount of dibutyl phthalate, measured in units of ml / 100g, measured using an abchometer by the method described in Japanese Industrial Standard K-6221-1975.

The term "surface area" is the value measured using nitrogen by the method described in American Society for Test-ing and Materials (ASTM) D 3037-73, which represents the area of 1 g of carbon black in m 2.

The resin component of this invention can be obtained by mixing a thermoplastic resin and carbon black uniformly. In addition to these essential ingredients, conventional additives such as lubricants, antioxidants, plasticizers and fillers may be added and mixed. The shape of the molded article from the resin mixture can be made by a process that creates a conventional shape. The resin composition has a volume resistivity of 10 ³ Ω · cm or less, more preferably 10 ² Ω · cm or less.

If this value exceeds the above-mentioned limit, it is difficult to achieve a satisfactory electroplating film.

As used above, "volume resistivity" is the value obtained by measurement by the method described in British Standard 2044 (Method 2). The molded article of the resin composition of the present invention can be successfully electroplated without prior chemical plating.

Therefore, chemical plating and any other pretreatment are omitted. That is, the molded product can be electroplated after the corrosion treatment. In other words, it can be corroded, activated, or increased.

Then it is electroplated. Each of these treatments, including electroplating, can be carried out essentially in conventional plating methods.

The electroplating film thus formed is strongly adhered to the molded product and thus has a good appearance and satisfactory material properties.

As described above, the present invention makes it possible to omit at least the conventional chemical plating process for electroplating plastic materials.

This method not only greatly reduces the cost of the pledge but also eliminates the cost of waste liquid treatment and is simpler than the conventional treatment process, so that the treatment liquid can be easily managed and the yield is increased.

In addition, it is possible to perform corrosion by using a corrosion solution having a low concentration of chromium ions, which is very advantageous in terms of preventing environmental pollution problems. Practical and good points of the present invention will be described in detail with reference to the following examples, where the ratio and percentage are by weight.

The term “ABS resin” means styrene-acrylonitrile-polybutadiene copolymer.

Example 1

MV가 사용된다. 이 ABS 수지(100부)와 흡유량이 350ml/100g이고 표면적 1000㎡/g인 카아본 블랙(15부)은 17Ωㆍ㎝의 체적 고유저항치를 갖도록 반부리 믹서에서 220℃로 12분간 혼련하여 조성물을 만든다. 이 조성물로부터 평판(70mm×140mm×2mm)을 성형된다.ABS resin (made by Sumidomo Nogadot Co., Ltd.)

MV is used. The ABS resin (100 parts) and carbon black (15 parts) having an oil absorption amount of 350 ml / 100 g and a surface area of 1000 m 2 / g were kneaded at 220 ° C. for 12 minutes in a half-blow mixer to have a volume resistivity of 17 Ω · cm. Make. The flat plate (70 mm x 140 mm x 2 mm) is shape | molded from this composition.

The plate was degreased with a C-15 cleaner, manufactured by Okuno Chemical Co., Ltd. and corroded with anhydrous chromium (400 g / l) solution and concentrated sulfuric acid (200 ml / l). The copper-plated electrolytic cell is strike-plated at a current density of 1 A / dm 2 and then plated at a current density of 3.5 A / dm 2.

The results are shown in Table 1.

Example 2

It is the same method as Example 1 for obtaining a flat plate except that the quantity of carbon-black is changed to 8 parts. The volume resistivity of the composition is 850 Ω · cm.

Plating was then performed in the same manner as in Example 1.

The results are shown in Table 1.

Example 3

Using 100 parts of ABS resin as in Example 1 and carbon black (40 parts) having an oil absorption of 200 ml / 100 g and a surface area of 600 m 2 / g, a flat plate was obtained in the same manner as in Example 1. The volume resistivity of the composition is 35 Ω · cm.

The plating is then carried out in the same manner as in Example 1.

The results are shown in Table 1.

Comparative Example 1

It was obtained in the same manner as in Example 1 by using the same ABS resin (100 parts) and the oil absorption amount as 95 ml / 100 g and carbon black (150 parts) having a surface area of 120 m 2 / g. The use of extremely large amounts of carbon black makes the kneading task complicated and even more difficult to break the reputation. The volume specific resistance is 720 Ω · cm.

The plating is then carried out in the same manner as in Example 1.

The results are shown in Table 1.

Comparative Example 2

Aside from changing the amount of carbon black used to 40 parts, the treatment method is carried out in the same manner as in Example 1 for obtaining a flat plate entirely.

Then plate. The volume resistivity of the composition is 1.8 × 10 ¹⁰ Ω · cm.

The results are shown in Table 1.

Comparative Example 3

The treatment method for obtaining a flat plate using ABS resin (100 parts) as in Example 1 and carbon black (40 parts) having an oil absorption of 300 ml / 100 g and a surface area of 350 m 2 / g was performed in the same manner as in Example 1. Is done.

Then plate. The volume resistivity of the composition is 3.5 × 10 ⁶ Ω · cm. The results are shown in Table 1.

Comparative Example 4

Aside from changing the amount of carbon black used in two parts, the treatment is carried out in exactly the same manner as in Example 1 for obtaining a flat plate.

Then plate. The volume resistivity of the composition is 8.9 × 10 ⁷ Ω · cm.

The results are shown in Table 1.

Reference Example 1

Using only ABS resin as in Example 1, plates plated by conventional plating methods (Surface Clearing-Degreasing-Corrosion-Neutralization-Activation-Sensitization-Chemical Plating-Electroplating) are made. The volume resistivity of the ABS resin is 5.3 × 10 ¹⁵ Ω · cm.

The results are shown in Table 1.

TABLE 1

Example 4

The thermoplastic resin and carbon black as shown in Table 2 are kneaded at 200 ° C. for 8 minutes with a half-blow mixer to make a composition. Thus, a 70 mm x 140 mm x 2 mm plate is formed from the composition and the plate is corroded with a corrosion solution containing chromium anhydrous (30 g / l) and concentrated sulfuric acid (500 ml / l) at 75 ° C. for 10 minutes. It is then strike-plated in a copper plating electrolyzer containing copper sulfate (200 g / l) and sulfuric acid (50 g / l) at a current density of 1 A / dm 2.

Then, formal plating is performed under an increase of 3.5 A / dm 2 of current density.

TABLE 2

Note: 1-3 and 8-18 are within the scope of the present invention and 4-7 are for comparison.

In the above table, the abbreviation of thermoplastic resin is as follows. PP, polypropylene; PVC, polyvinyl chloride; PS, polystyrene; PC, polycarbonate; PMMA, methacrylic resins; PSUs, polysulfones; PE, polyester; PAC, polyamides; SAN, styrene-acrylonitrile copolymers; PPO, polypanylene oxide; EVA, ethylene-vinyl acetate copolymer;

Example 5

Various kinds of thermoplastic resin mixtures and carbon blacks shown in Tables 3 and 4 were kneaded in the same manner as in Example 4 to form flat plates.

The obtained plate was corroded in the same manner as in Example 4, strike-plated and then formally plated.

TABLE 3

Note: Abbreviations for thermoplastics are shown in Table 2.

TABLE 4

Note: Abbreviations for thermoplastics are shown in Table 2.

Example 6

As shown in Table 5, the thermoplastic resin and the carbon black are kneaded at 200 ° C. for 3 minutes to obtain a mixture with a half-blow mixer. Then, the mixture was formed into a 70mm × 140mm × 2mm flat plate, and then corroded for 10 minutes at 75 ° C. with a corrosion solution containing anhydrous chromium (30g / ℓ) and concentrated sulfuric acid (500ml / ℓ). Neutralize with neutralizer D-25. Then, strike-plating is performed in a copper plating electrolyzer containing copper sulfate (200 g / l) and sulfuric acid (50 g / l) at a current density of 1 A / dm 2.

And formally plated under a current density increase of 3.5 A / dm 2.

TABLE 5

Note: Abbreviations for thermoplastics are shown in Table 2.

Example 7

The various thermoplastic resin mixtures and the carbon blacks shown in Tables 6 and 7 were kneaded in the same manner as in Example 6 to form flat plates. This plate is corroded and neutralized in the same manner as in Example 6. The strike is then plated and duly plated.

TABLE 6

Note: Abbreviations for thermoplastics are shown in Table 2.

TABLE 7

Note: Abbreviations for thermoplastics are shown in Table 2.

Example 8

MV(스미도모 노가닷그 회사제품)과 350ml/100g의 흡유량과 1000㎡/g의 표면적을 가지고 있는 카아본 블랙(10부)을 95Ωㆍ㎝의 220℃로 12분간 혼련한다. 이 혼합물로 부터 평판(70mm×140mm×2mm)을 만든다.Chlarastic as ABS resin (100 parts)

MV (manufactured by Sumidomo Nogadot Co., Ltd.) and carbon black (10 parts) having an oil absorption of 350 ml / 100 g and a surface area of 1000 m 2 / g are kneaded at 220 ° C. of 95 Ω · cm for 12 minutes. From this mixture a flat plate (70 mm x 140 mm x 2 mm) is made.

The oil thus obtained is removed from the plate obtained in this way with a C-15 washing solution manufactured by Oguno Chemical Co., Ltd.

Then, it was corroded with a corrosion solution containing 30 g / l anhydrous chromium and 500 ml / l concentrated sulfuric acid, and neutralized with D-25 neutralizer, manufactured by Oguno Chemical Co., Ltd., and then A-30 catalyst solution of Oguno Chemical Co., Ltd. The catalyst is treated with D-25, which is a product of Oguno Chemical Co., Ltd., and the accelerator is treated.

Then, strike-plating is carried out in a copper plating electrolyzer containing 200 g / l copper sulfate and 50 g / l sulfuric acid and having a current density of 1 A / dm 2, followed by formal plating at a current density of 3.5 A / dm 2.

Example 9

The treatment was carried out in the same manner as in Example 8 to obtain a flat plate, except that the amount of carbon black was changed to eight parts. The volume specific resistance of the mixture is 850 Ω · cm. Then, plating is performed in the same manner as in Example 8.

The results are shown in Table 8.

Example 10

As in Example 8, a flat plate was obtained in the same manner as in Example 8 using ABS resin (100 parts) and carbon black (40 parts) having a flow rate of 200 ml / 100 g and a surface area of 600 m 2 / g. The volume specific resistance of the mixture is 35 Ω · cm. Then, plating is performed in the same manner as in Example 8.

The results are shown in Table 8.

Comparative Example 5

A flat plate can be obtained in the same manner as in Example 8 using ABS resin (100 parts) as in Example 8 and carbon black (150 parts) having an oil absorption of 95 ml / 100 g and a surface area of 120 m 2 / g.

If you use too much carbon black, kneading is cumbersome, and even more, the plate is easily broken. The volume resistivity of the mixture is 720 Ω · cm. Then, plating is performed in the same manner as in Example 8.

The results are shown in Table 8.

Comparative Example 6

A flat plate was obtained and plated in the same manner as in Comparative Example 5 except that the amount of carbon black was changed to 40 parts. The volume resistivity of the mixture is 1.8 × 10 ¹⁰ Ω · cm.

The results are shown in Table 8.

Comparative Example 7

ABS resin (100 parts) as in Example 8 and carbon black (40 parts) having an oil absorption of 300 ml / 100 g and a surface area of 350 m 2 / g were used to obtain a flat plate in the same manner as in Example 8 do. The volume specific resistance of the mixture is 3.5 × 10 ⁶ Ω · cm. The results are shown in Table 8.

Comparative Example 8

Except for changing the usage amount of carbon black to 2 parts, the same process as in Example 8 was employed solely to obtain a flat plate, and the obtained flat plate was plated. The volume resistivity of the mixture is 8.9 × 10 ⁵ Ω · cm.

The results are shown in Table 8.

Reference Example 2

After the plate was made using only ABS resin as in Example 8, it was plated by conventional methods (surface cleanup-degreasing-corrosion-neutralization-activation-sensitization-chemical plating). The results are shown in Table 8.

TABLE 8

Example 11

As shown in Table 9, the mixture was kneaded at 200 ° C. for 8 minutes with a half-blow mixer to obtain a mixture of thermoplastic resin and carbon black. A 70 mm × 140 mm × 2 mm plate is then formed from the composition and soaked for 10 minutes at 60 ° C. for precorrosion in an aqueous acid containing 200 ml / l toluene and 100 ml / l trichloroethylene.

The mixture was then rinsed for 15 minutes at 78 ° C. in a warm aqueous solution containing terepine (60%) and surfactant (20%) and at 75 ° C. with a corrosion solution containing 500 g / l concentrated sulfuric acid, 30 g / l anhydrous chromium. It is corroded for 10 minutes and neutralized with the neutralizer D-25, which is manufactured by Oguno Chemical Co., Ltd., and then catalyzed by the catalyst A-30 of Oguno Chemical Co., Ltd.

Then, accelerated treatment was carried out with D-25 of Oguno Chemical Co., Ltd. and strike-plated in a copper plating electrolyzer containing 200 g / l copper sulfate and 50 g / l sulfuric acid at a current density of 1 A / dm 2. Then, form a plated at a current density of 3.5A / dm ² .

In run numbers 1 to 7 and 13 where polypropylene and polyester are used, instead of catalytic treatment, Tung sensitizer, manufactured by Oguno Chemical Co., Ltd. Activate using the product TMP activator.

TABLE 9

Note: Progress numbers 1 to 3 and 8 to 18 are within the scope of the present invention, and 4 to 7 are for comparison. Abbreviations for thermoplastic resins are shown in Table 2.

Example 12

As shown in Table 10 and Table 11, kneading was carried out in the same manner as in Example 11 to form a flat plate with various thermoplastic resin mixtures and carbon black. These plates are corroded, neutralized, sensitized, activated (as with the catalyst and promoter treatments in Table 11), strike-plated and duly plated.

TABLE 10

Note: Abbreviations for thermoplastics are shown in Table 2.

TABLE 11

Note: Abbreviations for thermoplastics are shown in Table 2.

Claims (1)

A molded article composed of a composition comprising 100 parts by weight of a single or two or more thermoplastic resins and 3 to 100 parts by weight of carbon black having an oil absorption amount of 200 ml / 100 g or more and a surface area of 500 m 2 / g or more and having a volume resistivity of 10 ³ Ω · cm or less. Method for producing a plated product, characterized in that the electroplating directly without chemical plating in advance.