JPH0246710B2 - MUDENKAIMETSUKISENINOSEIZOHO - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a method for producing electroless plated fibers in which an electroless plated film is formed on fibers of acrylonitrile polymer. The metal-plated coated fiber material according to the present invention can be used as a conductive material, an auxiliary material, a resin, a paint, an adhesive, or a material for other composite materials. [Prior art] Due to advances in technology and the development of applications for plating products, electroless plating can now be applied to any material, organic or inorganic, and regardless of its shape or size. There is. By the way, when electroless plating is applied to a base material, it is necessary to perform a plating pretreatment because the treatment cannot be performed directly. Conventionally, not only acrylonitrile fibers but also
As a pre-plating treatment for other synthetic fibers, the following operations have generally been performed. That is, cleaning treatment of the base fiber with an alkaline degreasing solution, etc.; next, surface roughening treatment with, for example, a chromium mixed acid etching solution; sensitization treatment with an acidic solution of stannous chloride; and then activation treatment with an acidic solution of palladium chloride. Pretreatment operation or surface roughening treatment with etching solution, first chloride
Typically, pretreatment operations include catalytic treatment with a colloidal solution of tin and palladium chloride; followed by accelerated treatment with an acid or alkali solution. [Problems to be Solved by the Invention] However, the pretreatment method using each of these operations is complicated and time-consuming, considering that (1) the treatment process is long and washing with water cannot be omitted between each process; It is a very problematic operation, not only because it takes a lot of water and is unproductive, but also because it generates a large amount of wastewater and must be treated; (2) In particular, the chromic acid-sulfuric acid mixture used as a chemical etching solution Since the acid concentration is high and the aging process is rapid, it is unavoidable to take measures to treat the aged waste liquid and increase the cost; (3) Even if the fiber surface is roughened by chemical etching, the adhesion of the plating film to the acrylonitrile fiber remains. It has various drawbacks such as poor adhesiveness and peeling problems, and a reasonable method of improvement has been expected. [Means for Solving the Problems] In view of the above-mentioned problems, the present invention provides a method for electroless plating using acrylonitrile fibers as a base material, which does not require complicated pretreatment operations as in the past. The object of the present invention is to perform an electroless plating process by directly catalyzing the process without using a catalytic converter, and to produce an industrially advantageous plated fiber product with excellent adhesion. Therefore, an electroless method is proposed in which fibers made of the acrylonitrile polymer of the present invention (hereinafter referred to as PAN fibers) are catalyzed by contacting them with an aqueous noble metal salt solution, and then subjected to an electroless plating treatment. The purpose of the present invention is to provide a method for producing woven fibers. [Function] Applicable as a plating base material in the present invention
PAN fiber is a polymer of acrylonitrile or a copolymer of acrylonitrile and other monomers, and examples of other monomers include vinyl compounds such as vinyl chloride, vinylidene chloride, vinyl acetate, and styrene, acrylic acid, and methane. Examples include acrylic acid, esters thereof such as methyl and ethyl, acrylic acid and itaconic acid, and fibers made of these monopolymers or copolymers are known. Therefore, there is no particular reason to limit it as long as it is a PAN fiber product, and textile products include short fibers, short fibers,
It may be either long fiber or woven fabric. Electroless plating according to the present invention does not require a long pretreatment process as in the conventional method, and it is only necessary to carry out a catalytic treatment by directly bringing the fiber base material into contact with an aqueous noble metal salt solution. Here, the meaning of pre-treatment to perform direct catalytic treatment is that if the base fiber is not contaminated with oily components or other components due to surface treatment or other processing, it can be directly catalyzed as shown below. However, if this is not the case, cleaning treatment is performed to remove stains on the fiber surface as necessary, and then catalytic treatment is performed. The catalytic treatment varies depending on the type of substrate, subsequent plating method, and other conditions, but in most cases 0.01 to 1.0 g/, preferably
By contact treatment of an aqueous solution of one or more noble metals selected from the group consisting of gold, silver, platinum, and palladium at a concentration of 0.05 to 0.2 g/ with a substrate at a liquid temperature of 10 to 30°C. can be done.
As a contact treatment method, in many cases, immersion for several minutes to several tens of minutes, spraying, etc. can be used. Although the detailed mechanism is not clear, the reason why a plating film can be formed immediately after direct catalytic treatment on PAN fiber substrates, unlike conventional methods, is probably due to the base material. This is thought to be because the nitrile group of the material captures a noble metal, such as palladium, and also donates electrons in the nitrile group to palladium. Thus, through catalytic treatment, precious metals are
Since it is supported on the PAN fiber base material, the subsequent electroless plating operation can be carried out promptly. That is, the catalyzed PAN fiber base material is washed with water and subjected to the next electroless plating treatment. As the plating liquid used in the present invention, various conventionally known plating liquids can be employed. The metals that should form the plating film include Ni, Co,
Cu, alloys thereof, others, Pb, Ag, Au
Precious metals such as Therefore, in general, an electroless plating solution is a solution composed of the metal salt to be plated, a reducing agent, a complexing agent, a buffering agent, a stabilizer, etc. as described above.
Examples of reducing agents include alkali hypophosphite, alkali borohydride, aminoborane, hydrazine, and formalin. Examples of complexing agents include formic acid, acetic acid, succinic acid, citric acid, tartaric acid, malic acid, and lactic acid. , gluconic acid or its alkali metal salts and ammonium salts, amino acids such as glycine, amines such as ethylenediamine and alkyl amines, as well as ammonia, EDTA, pyrophosphoric acid (salt), etc., and one or more of them may be used. It may be. In performing electroless plating in the present invention, it is of course possible to use the conventional immersion plating method in which a plating solution is prepared and the plating base material is immersed in it, but it is also possible to use a method that can be dispersed in water. In addition to the method described above, the plating base material is preferably prepared by an addition method in which the plating base material is made into an aqueous suspension and a part or all of the plating liquid composition is added individually and simultaneously. The addition method is a method developed by the present inventors,
For example, Japanese Patent Application Laid-Open No. 60-59070, Japanese Patent Application No. 60-66505
The details are explained in the publication. In this way, whether the immersion method or the addition method is used is related to the shape and size of the plating base material, so it may be adopted as appropriate, but the composition of the electroless plating solution will differ depending on the method used. . For example, a typical composition of the plating solution when using the dipping method is, for example, 10 to 100 g of metal salt such as Ni or Co,
The amount ranges from 5 to 100 g of a reducing agent such as hypophosphite, 5 to 200 g of a complexing agent, and 5 to 100 g of a PH buffer, but in the case of the addition method, the concentration is generally higher than that of the immersion method. This solution can be used effectively up to saturation concentration. To explain the addition method in detail, an aqueous suspension is prepared in which a water-dispersible PAN fiber base material is sufficiently dispersed in water or an aqueous medium such as an acid, an alkali, or a complexing agent, and then an electroless plating solution is added. By gradually adding them together or individually, hydrogen is generated, a plating reaction occurs, and a metal plating film is formed on the substrate. In either method, the reaction is carried out at a temperature of room temperature to 90°C, and is preferably carried out with stirring so that a film is uniformly formed. The thickness of the plating film on the base material is not limited at all and may be determined depending on the intended use. After the generation of hydrogen gas has stopped, the plating process is completed by holding it for a while, and then separating it by a conventional method.
It can be obtained as a product by washing with water and drying. [Example] Examples 1 to 6 100g of each short fiber shown in Table 1 was heated to 0.2% at room temperature.
g/palladium chloride was added to hydrochloric acid acidic cleaning solution 1, stirred with a stirrer for about 30 minutes, filtered, and repulped once. 100 g of the short fibers pretreated in this way were added to a 20 g/aqueous sodium tartrate aqueous solution adjusted to pH 9, dispersed well using a stirrer, and then heated to 65°C to form an aqueous suspension. was prepared. Next, apply the electroless plating solution shown in Table 2.
Liquid (a) and liquid (b) were each added at a rate of 50 ml/min to the above-mentioned suspension under stirring. After the entire amount was added, stirring was continued while maintaining the temperature at 65° C. until hydrogen generation stopped. Then, after filtration, repulp washing, filtration, and drying. In this way, short fibers having a uniform and strong nickel film on the surface were obtained. Example 7 100 g of cashmilon cloth was immersed in 0.2 g of palladium chloride/hydrochloric acid acidic solution 1 at 20°C, treated for about 30 minutes while stirring the solution up and down, and the water was squeezed out through a roll squeezer. It was washed with water once and the moisture was thoroughly squeezed out through a roll squeezer. The fabric thus pretreated was immersed in electroless nickel plating solution 10 (Blue Scheumer, manufactured by Nippon Kanizen Co., Ltd.) adjusted to 85 to 90°C, and plated for about 5 minutes. After the plating-treated cloth was thoroughly washed with water, the moisture was squeezed out using a roll wringer, and the cloth was dried using a dryer. In this way, a cloth having a uniform and strong nickel film on its surface was obtained.

【table】

[Table] Example 8 Bonnel cut into 2.0 mm pieces (manufactured by Mitsubishi Bonnell,
100 g of the fiber (fiber diameter: 19.0 μm) was added to 0.1 g/silver nitrate aqueous solution 1 at 15° C., and after immersion with stirring for about 30 minutes, filtration and repulsion washing were performed once. 100g of short fibers pretreated in this way were heated to a liquid temperature of 25℃.
Then, it was added to an electroless copper plating solution (Surkap ELC-90, manufactured by Uemura Kogyo) 15 whose pH was adjusted to 12.6, and plating was performed for about 20 minutes while stirring. Next, after performing filtration, repulsion washing and filtration, it was dried. In this way, short fibers having a uniform and strong copper coating on the surface were obtained. Comparative Example 1 100 g of Cashmilon (manufactured by Asahi Kasei, fiber diameter 13.5 μm) shredded into 0.3 mm pieces was treated with an etching solution (solution temperature 60 g) consisting of 100 g of chromic anhydride and 200 ml of sulfuric acid.
C) 1 and immersed for 5 minutes while stirring, filtered and repulfed three times using a stainless steel wire mesh. Next, palladium chloride 0.1g/
, 5 g of stannous chloride and 100 ml of hydrochloric acid were immersed in a catalyzer solution 1 for 5 minutes at a temperature of 25°C. After filtration, it was immersed in 50 g/accelerator liquid 1 for 5 minutes at a liquid temperature of 25° C., filtered and repulsed once, and then filtered. The short fibers that have been pretreated in this way are
The plate was immersed in an electroless nickel plating solution (Blue Scheumer, manufactured by Nippon Kanigen) adjusted to 85°C and was plated while stirring. The short fibers that had been plated were filtered, repulsed, and dried after filtration.
In this way, short fibers having a uniform nickel film on the surface were obtained. Comparative Example 2 100g of Cashmilon cloth was mixed with 100g of chromic anhydride/
and an etching solution consisting of 200 ml of sulfuric acid (liquid temperature
(60℃) 1 and gently agitated the cloth.
After 5 minutes, remove the cloth and wash thoroughly with running water. Next, palladium chloride 0.1g/, stannous chloride 5g/
and hydrochloric acid (100ml) for 5 minutes at a temperature of 25°C. The water was squeezed out through a roll wringer, washed with running water, and the water was squeezed out again using a roll wringer.
Next, it was immersed in accelerator solution 1 containing 50 g of sulfuric acid for 5 minutes at a temperature of 25° C., and then the water was squeezed out through a roll squeezer. After washing with running water, the water was squeezed out again using a roll squeezer. The fabric thus pretreated was then plated using the same electroless copper plating solution as in Example 8 under the same working conditions.
In this way, a cloth was obtained which had a non-uniform copper coating with slight unplated areas left here and there. Measurement of adhesion between film and substrate In a mortar, weigh the calculated amount of epoxy resin main agent and curing agent [Cemedine 1500, manufactured by Cemedine Co., Ltd.] and the calculated amount of the metal-coated short fibers obtained in the example or comparative example. The mixture was taken and kneaded well for 5 minutes. Next, this was placed in a mold to create a plate-shaped sample [2 x 30 x 50 (mm)]. Next, the resistance value of the obtained molded plate was measured,
When the volume resistivity values were determined, the results shown in Table 3 were obtained.

[Table] Short fibers with poor adhesion between the plating film and the substrate cause peeling when kneaded with epoxy resin, resulting in an increase in volume resistivity. Therefore, it is possible to indirectly compare the adhesion of the films by comparing the volume resistivity values of the samples, but as the results in Table 3 show, all of the products of the present invention were better than the comparative examples. It can be seen that the adhesion of the plating film is excellent despite the simple pretreatment. [Effects of the Invention] According to the method of the present invention, electroless plating of PAN fibers can be carried out very industrially advantageously.
When comparing its specific advantages with the conventional method, the following points can be raised. (1) Significant reduction in pretreatment steps can be achieved: Conventional method (a) Cleaning treatment - Water washing - Chemical etching treatment - Water washing - Sensitization treatment - Water washing - Activation treatment - Pretreatment process by water washing Conventional method (b) Cleaning Treatment - Water washing - Chemical etching treatment - Water washing - Catalytic treatment - Acceleration treatment - Pretreatment process by washing Method of the present invention (Cleaning treatment - Washing -) Catalytic treatment - Pretreatment by washing Just go. (2) Chemical etching treatment can be omitted (a) Since the plating process proceeds without roughening the fiber surface, fiber strength does not deteriorate and a plating film with excellent appearance can be obtained. (b) Since chromic acid is not used, chromium wastewater treatment is not required. (3) By significantly shortening the pretreatment time, the amount of chemicals used is reduced, and productivity and economic efficiency are improved. (4) The adhesion between the fiber and the plating film is improved.

Claims (1)

[Claims] 1. Production of electroless plated fibers, characterized in that a fiber product of an acrylonitrile polymer is brought into contact with an aqueous noble metal salt solution to undergo desolvation treatment, and then subjected to electroless plating treatment. Law. 2. The acrylonitrile polymer is a monopolymer of acrylonitrile, or a combination of acrylonitrile and one or more monomers selected from the group consisting of vinyl monomers, acrylic monomers, and unsaturated carboxylic acids. Claim 1 which is a copolymer
A method for producing electroless plated fibers as described in . 3. The method for producing electroless plated fibers according to claim 2, wherein the vinyl monomer is selected from the group consisting of vinyl chloride, vinylidene chloride, vinyl acetate, and styrene. 4. Production of electroless plated fiber according to claim 2, wherein the acrylic monomer is selected from the group consisting of acrylic acid, methacrylic acid, methyl acrylate, ethyl acrylate, methyl methacrylate, and ethyl methacrylate. Law. 5. The method for producing electroless plating according to claim 2, wherein the unsaturated carboxylic acid is selected from acrylic acid or itaconic acid. 6. The method for producing electrolessly plated fibers according to claim 1, wherein the noble metal salt aqueous solution is an aqueous solution of one or more soluble salts selected from the group consisting of gold, silver, platinum, and palladium.