JPS5821038B2 - Manufacturing method of plated products - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a novel method for producing plated products from a composition of a copolymer (A) consisting of vinyl cyanide, an aromatic vinyl, and a conjugated diene rubber, and carbon black (g). It is related to.

Plastic has traditionally been used as a material for plated products in various fields.

This is because plastics have advantages over metals, such as greater freedom in design due to ease of molding and the ability to produce lightweight products.

In particular, copolymers consisting of vinyl cyanide, aromatic vinyl, and conjugated diene rubber (generally called ABS resin)
is widely used as a plating plastic because the resulting plastic products have superior appearance and performance compared to other plastics.

However, these plastics are nonconductors and cannot be electroplated directly, requiring complicated pretreatment steps as described below.

To explain the contents of each process, there is a surface treatment process to remove scratches, debris, etc. from the surface of the plastic molded product, a degreasing process to remove oil stains, etc. attached to the surface of the molded product, and a high concentration treatment process to make the plastic surface hydrophilic. an etching process using a chromium-containing treatment solution; a neutralization process for removing chromium by pumping it from the etching bath;
A catalyst treatment process in which palladium, etc. is attached to a hydrophilized surface, an accelerator treatment process in which the attached palladium, etc. is activated, and an electroless process in which a thin metal film of nickel or copper is deposited on a plastic surface using palladium metal etc. as a catalyst. This is a plating process, an electroplating process for copper, nickel, chrome, etc.

Compared to metal plating, plastic plating, which requires many, complex, and difficult-to-manage chemical processing steps, is more susceptible to pollution due to waste liquid from each processing step, and products due to the complexity of the steps. There are many problems such as variations in quality and rising costs.

In addition, in the etching process, usually - chromic anhydride 40
0 g/! 11 Concentrated sulfuric acid, about 200d/7.

A treatment solution with a high chromium concentration is used.

Therefore, wastewater treatment is accompanied by the problem of chromium pollution.

In the current plating process, there are various problems when using a treatment solution with a low chromium concentration, and it is difficult to reduce the chromium concentration.

The present inventors wish to reduce the number of steps described above.

The present invention was arrived at as a result of intensive research into methods that are advantageous from an economic and pollution prevention perspective.

That is, the present invention uses 100 parts by weight of a copolymer (A) consisting of vinyl cyanide, aromatic vinyl, and conjugated diene rubber, and an oil absorption amount of 200-(DBP)/10 ON.

or more, and the surface area is 500 m2/g by nitrogen adsorption method.
A molded article made of a composition consisting of 3 to 100 parts by weight of the above carbon black (B) and having a volume resistivity of about 10 3 Ω・or less is subjected to etching, neutralization, catalyst and accelerator treatment; This is a method for manufacturing plated products characterized by applying electroplating.

To explain the present invention in more detail, the copolymer diagram used in the present invention is not limited in its manufacturing method, composition, etc., but vinyl cyanide and aromatic vinyl are acrylonitrile and styrene, respectively. Copolymer (A) 65, in which the conjugated diene rubber is polybutadiene, styrene-butadiene copolymer, or acrylonitrile-butadiene copolymer, is preferred.

It is generally called ABS resin.

Furthermore, the addition of ordinary auxiliary agents such as lubricants, antioxidants, and plasticizers will not have any adverse effect on the present invention.

The carbon black (B) used in the present invention has an oil absorption of 200 yd/1005+ or more and a surface area of 5
00m2/g or more, and if carbon black is outside this range, an electrodeposited film may not be formed even if electroplated directly after accelerator treatment, or a good plated product may not be obtained even if it is formed. .

In addition, the amount of carbon black (B) relative to 100 parts by weight of the copolymer (A) is 3 to 100 parts by weight, and if it is 3 parts by weight or less, the oil absorption is 200d/10M or more and the surface area is 500m27i or more. Even with carbon black, an electrodeposited film cannot be formed.

Moreover, if it exceeds 100 parts by weight, the physical properties of the molded product will be significantly inferior.
It cannot be put to practical use.

More preferably, it is 5 to 70 parts by weight, and most preferably 8 to 25 parts by weight.

Note that oil absorption is defined in JIS K-6221-197.
It means the value measured according to 5, and the amount of DBP (dibutyl phthalate) measured by an abutometer is nt7! /100 It is expressed in units of El.

The surface area is a value measured according to ASTM D 3037-73, and is expressed in units of m2/&.

Oil absorption amount of carbon black (B) is 200rn1710
Less than 0g or surface area 5007712/,! If it is less than i', a product with a satisfactory electrodeposited film cannot be obtained.

In the present invention, the volume resistivity value of the composition must be 10 3 Ω·α or less.

If 103Ω·5 is obtained, a product with a satisfactory electrodeposited film cannot be obtained.

More preferably, it is 102 Ω-m or less.

In addition, the volume resistivity value is Br itish S
Means a value measured according to standard 2044 (Metbod 2).

According to the present invention, since electroplating can be performed directly after the accelerator treatment, it is possible to omit the electroless plating step, which is not necessary in conventional methods of manufacturing plated products.

Although electroplating can be applied directly to the composition of the present invention after etching, if the composition is further subjected to neutralization, catalyst and accelerator treatment after etching as in the present invention, it will be easier during electroplating (especially strike plating). metal deposition time can be shortened.

Therefore, the electroless plating solution required in the electroless plating process is not required at all, and not only the cost of reagents can be greatly reduced, but also the cost of waste liquid treatment is not required at all.

Since it is simpler than conventional treatment processes, it is easier to manage the treatment liquid and increase production.

Furthermore, etching can be carried out satisfactorily with an etching solution with a low chromium concentration, which is advantageous in terms of pollution control.

Examples will be described below, but the present invention is not limited thereto.

Note that all parts by weight are abbreviated as parts.

Example I Using Clarastic@MV (manufactured by Sumitomo Naugatac) as the ABS resin, 100 parts of this ABS resin and 10 parts of carbon black with an oil absorption of 350d7100g and a surface area of 1000m2/g were heated at 220° in a Banbury mixer.
C91 Mix for 2 minutes, volume specific.

A composition having a resistance value of 95Ω/sieve was obtained.

A flat plate (70 m x 140 m x 2 m) was molded from this composition.

This flat plate was degreased with C-15 cleaner liquid manufactured by Jitsukei Pharmaceutical Co., Ltd., chromic anhydride 30fi/111 concentrated sulfuric acid 500rnl/
Etching treatment with etching solution II, neutralization treatment with D-25 neutralizing agent manufactured by Jitsukei Pharmaceutical Co., Ltd., A-3 manufactured by Jitsukei Pharmaceutical Co., Ltd.
Immediately after catalyst treatment with 0 Catalyst A and accelerator treatment with Jitskei Pharmaceutical Co., Ltd. D-25 accelerator liquid.

Acid silver 200 El/111 sulfuric acid 50. ! Strike plating was performed at a current density of IA/dTrL2 in an electrolytic copper plating bath of iI/l, and then main plating was performed at a current density of 3.5 A/d7712.

During strike plating, the metal is folded over the entire surface of the flat plate.

It took 3 minutes to serve.

Example 2 A flat plate was obtained in the same manner as in Example 1 except that the amount of carbon black was changed to 8 parts.

Note that the volume resistivity value of the composition was 850Ω·sieve.

Thereafter, plating was performed in the same manner as in Example 1.

It took 5 minutes for the metal to deposit on the entire surface of the flat plate during strike plating.

The results are shown in Table 1.

Example 3 100 parts of ABS resin same as Example 1 and oil absorption amount 200d/
A flat plate was obtained in the same manner as in Example 1 from 40 parts of carbon black having a surface area of 10 (1, 600,772,2/,!i').

The volume resistivity value of the composition was 35Ω·sieve.

Thereafter, plating was performed in the same manner as in Example 1.

In strike plating, it took 1 minute for metal to be deposited over the entire surface of the flat plate.

The results are shown in Table 1.

Comparative Example 1 100 parts of ABS resin same as Example 1 and oil absorption 95yd
/100. ! A flat plate was obtained in the same manner as in Example 1 from 150 parts of carbon black having a volume of 1207712/.9.

In addition, since the amount of carbon black was extremely large, the kneading process was complicated, and the flat plate was also extremely brittle.

Further, the volume resistivity value of the composition was 720Ω·sieve.

Thereafter, plating was performed in the same manner as in Example 1.

The results are shown in Table 1.

Comparative Example 2 A flat plate was obtained and plated in the same manner as in Comparative Example 1, except that the amount of carbon black was changed to 40 parts.

In addition, the volume resistivity value of the composition is 1.8 x 101O
Ω It was a hard job.

The results are shown in Table 1.

Comparative example 3 100 parts of ABS resin same as Example 1 and oil absorption amount 300y
d/100. ! EXAMPLE 1 A flat plate was obtained in the same manner as in Example 1 using 40 parts of carbon black having a surface area of 350 m2/E/, and plated.

In addition, the volume resistivity value of the composition was 3.5×10 6 Ωq dish.

The results are shown in Table 1.

Comparative Example 4 A flat plate was obtained and plated in the same manner as in Example 1, except that the amount of carbon black was changed to 2 parts.

Incidentally, the volume resistivity value of the composition was 8.9×10 5 Ω·.

The results are shown in Table 1.

Reference Example 1 A flat plate was created using only the ABS resin used in Example 1,
Plating was carried out using the usual plating method (surface preparation - degreasing - etching - neutralization - catalytic accelerator - electroless plating).

The results are shown in Table 1.

Reference Example 2 Using the flat plate used in Example 1, the surface was leveled in the same manner as in Example 1.
After degreasing and etching treatment, copper sulfate 200% is applied directly.
j9/11. IA in a sulfuric acid 509/11 electrolytic copper plating bath
Strike plating was performed at a current density of /drrL2, and then main plating was performed at a current density of 3.5 A/d7712.

In the strike plating, it took 6 minutes for the metal to be deposited on the entire surface of the flat plate.

The adhesion strength of the electrodeposited film was 1.5 Kp/crIL.

Claims (1)

[Claims] 1. 100 parts by weight of a copolymer (A) consisting of vinyl cyanide, aromatic vinyl, and conjugated diene rubber, and an oil absorption of 20 parts by weight.
0-(DBP)/10i or more and a surface area of 500@2/& or more by nitrogen adsorption method B) Carbon black consisting of 3 to 100 parts by weight and a volume resistivity of 103
A molded product made of a composition that is Ω/Meio is etched,
A method for producing a plated product, characterized by applying electroplating directly after neutralization, cathode, list and accelerator treatments. 2. The method for producing a plated product according to item 1 above, wherein the vinyl cyanide and the aromatic vinyl are acrylonitrile and styrene, respectively. 3. The method for producing a plated product according to item 1 above, wherein the conjugated diene rubber is polybutadiene, styrene-butadiene copolymer, or acrylonitrile-butadiene copolymer. 4. The method for producing a plated product according to item 1 above, wherein the carbon black (B) is 5 to 70 parts by weight. 5. The first material having a volume resistivity value of 102Ω・sieve or less
Method for manufacturing plated products described in Section 1.