JPS61296174A - Production of brass coated fiber - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a method for producing brass-coated fibers.

BACKGROUND OF THE INVENTION The most common method of forming brass coatings on fibers is electroplating. This method involves passing the fiber through a plating bath consisting of copper cyanide and zinc cyanide. However, since this method handles toxic cyanide, it not only poses health and safety problems, but also has the drawback that treatment of plating waste liquid is troublesome. Also, this is a problem common to plating methods, but it is very difficult to maintain a constant composition of the plating bath, that is, the proportion of copper and zinc, and the concentration of the plating solution, making it difficult to form a brass coating with a constant composition. It also has the disadvantage of being difficult.

Other methods include thermal spraying using gas or plasma, and vacuum evaporation. However, the former method has the disadvantage that it is prone to the problem of so-called one-sided coating, in which brass adheres only to the side facing the gas or plasma source, and that it is difficult to form a uniform coating. Also, the latter method
The disadvantage is that the so-called dezincification phenomenon occurs, in which the zinc in the brass vaporizes and evaporates, making it difficult to keep the composition of the brass constant.

On the other hand, Japanese Patent Application No. 58-2194.87 proposes a method in which copper-coated fibers are passed through zinc vapor to diffuse zinc into the copper coating, thereby alloying copper and zinc to form brass. ing. This method is effective when the fiber is a monofilament. However, if the fiber is in the form of a strand (fiber bundle), it may be difficult to form a brass coating with a stable composition, or it may be difficult to form a brass coating with a stable composition.
There is a problem in that it is difficult to operate for a long time in 11.

SUMMARY OF THE INVENTION The object of the present invention is to solve the above-mentioned drawbacks of the conventional methods and to produce fibers with a brass coating of stable composition, regardless of the fiber form, without using harmful cyanide. Yes, and f1
The purpose of the present invention is to provide a method for easily manufacturing crested ζ.

Means for Solving the Problems In order to achieve the above object, this method uses fibers coated with copper and zinc in layers.
A method for producing a brass-coated fiber is provided, which comprises heating the fiber to C to diffuse zinc into the copper, alloying the copper and zinc to form brass, and forming a brass coating on the fiber. Ru.

To explain this invention in detail, in this invention, first, a fiber is coated with copper and zinc in layers.

Examples of the above-mentioned fibers include flame-resistant fibers, carbon fibers, graphite fibers, glass fibers, alumina fibers, silicon carbide fibers,
1i11, etc., which can withstand temperatures above 400°C, are usually in the form of monofilament or monofilament. However, from I, textiles and pine 1~,
Braided silk or Chibui T are all suitable.

Coating with copper or zinc 1. However, it is too difficult to form by the conventional method of λ[1.
In the case of graphite fibers (with 1, for example, a carbon fiber braid), an electroplating method can be used. Further, in the case of fibers whose conductivity is not affected, such as glass fibers and alumina fibers, the electrolytic method can be used. In addition, it is also possible to use methods such as solvent or vapor deposition.

The thickness of the copper or zinc coating may be arbitrary. In short, it can be determined according to the composition (color tone) of the brass coating. For example, brass coating that quickly turns golden is 1! ? In most cases,
The coating thickness of copper and zinc is adjusted so that the copper content is 40 to 90%, preferably 60 to 85%. However, since the zinc coating vaporizes during the heat treatment process described below and some of it leaks, the thickness must be made to allow for the leakage valve.

Generally, when using the electroplating method, it is 0.1~/1μ
m, or 0.1 to 2 in the case of electroless plating
Approximately μm is appropriate. In addition, when the fibers are in an aggregated state, the copper or zinc coating is applied to each fiber forming the aggregate.
Form into a book fiber (single fiber) so that it covers. In the case of woven fabrics, the fibers may be coated with copper and zinc before being woven.

The order of coating is preferably copper first. This is because, for example, when forming a J: coating using the electroplating method, if the zinc coating is formed first, not only will the coating formation speed be similar, but the zinc will oxidize rapidly and the formation of the copper coating will be delayed. In this invention, next, the fiber coated with copper and zinc in layers is heated to 4-00 to 1050'C to diffuse zinc into the copper. At the same time, these copper and zinc are alloyed to make brass. This yields brass-coated fibers.

This process will be explained using a drawing. In the drawing, the copper/zinc coating is wound around the bobbin 1! The LLI fiber 2 is introduced at a constant speed into a heat treatment tube 4 heated by an electric furnace 3, and while traveling inside the heat treatment tube 1, 4. OO~
Heated to 1050'C. This vaporizes the zinc, which diffuses into the copper coating and alloys with the copper to form brass. In other words, it is the twist at which the brass coating is formed. 8 tons of the obtained brass-coated fibers are wound onto a bobbin 9.

In the above, the heat treatment tube 4 is made of heat-resistant material V3+ such as quartz, and inert gas introduction tubes 5.6 such as argon gas or nitrogen gas are connected to both longitudinal ends of the heat treatment tube 4 to introduce the inert gas into the heat treatment tube. Air flow and copper/zinc coated Nl1
This prevents air from being brought in by the i-fiber 2. Further, in the heat treatment tube 4, an introduction tube 7 for introducing a reducing gas such as hydrogen gas is provided with a large number of holes in the longitudinal direction.
A reducing gas is introduced from the introduction pipe 7 to maintain the inside of the heat treatment tube 4 in a reducing atmosphere.

In the above, the temperature inside the heat treatment tube is maintained at 4-00 to 1050°C because zinc does not vaporize below 400°C, and when the temperature exceeds 1050°C, the copper coating peels off.
This is because brass-coated fibers cannot be manufactured in either case because they are easy to fabricate. Preferred ambient temperature
η is /119~800'C1 more preferable [5 no:/
150-700 °○.

Copper/zinc'4) creates a reducing atmosphere inside the heat treatment tube.
This is because when the zinc coating of the coated fiber is oxidized, it is effective in removing the oxygen in the zinc oxide by reacting with the primary gas and forming a brass coating with excellent color tone. be. In addition, the aqueous atmosphere is also effective in preventing the formed brass coating from being oxidized by oxygen leaking into the heat treatment tube.

The composition of the brass forming the coating is influenced by the running speed of the copper/zinc coated fiber, the length of the heat treatment tube, the heating temperature, etc., in addition to the thickness of the copper and zinc coating mentioned above. In other words, by changing these conditions, a brass coating of any composition can be obtained with Jz. By the way, according to experiments conducted by the Ministry of Invention and others, the above-mentioned conditions are met! 1), brass coatings with a very wide range of compositions have been obtained, ranging from a few percent to more than 50 percent zinc. Note that the traveling speed of the copper/zinc coating w11t varies depending on the length of the reaction tube, heating temperature, flow rate of atmospheric gas, etc., but is usually approximately 0.2 to 5 m/min or appropriate. Further, the flow rate of the atmospheric gas is preferably about 100 to 50,000 C/min.

The brass-coated 1” dH fiber produced by the method of this invention is
It can be used for various purposes. For example, a carbon fiber/brass composite material can be produced by arranging brass-coated carbon fibers in a die and pressing them into a hole. That is, it can be used as a molding material for fiber/brass composite materials. Such composite IJ materials, especially composites using carbon fiber or graphite fiber 1. ()l'3+ is used as a component of general machinery and equipment that requires corrosion resistance, such as bearings, vanes, brake shoes, etc. (as an A, boiler), seawater equipment, etc. It is useful as Further, it can also constitute a speaker diaphragm, a radio wave shielding material, an antistatic material, and an antenna.

According to the method of this invention, as mentioned above, the composition of the brass can be freely controlled and the color tone of the coating can be varied. For example, the coating has a small amount of zinc. When the amount of zinc is increased, it becomes golden yellow, and when the amount of zinc is further increased, it becomes yellow.Therefore, the decoration of fishing rods, golf shafts, tennis rackets, skis, etc. made of fiber/fat composite materials. If used in volumes, it can give them a design effect.

Example A carbon fiber string Patreca 300 manufactured by Toshi Co., Ltd., with an average single yarn diameter of 7 μm and 3,000 pieces of Neuramen I-1, was coated with copper by electroplating using a copper sulfate solution as a 1-solution.Copper The coating is applied to each single fiber, and its average thickness is approximately 1.1
It was μm.

Next, the copper-coated carbon fiber was coated with zinc by electroplating using zinc sulfate as a plating solution.

The thickness of the zinc coating was approximately 0.2 μm.

Next, according to the process shown in the drawings, the copper/zinc coated carbon fiber is made to run continuously at a speed of 0.5 m/min inside the heat-treated tube 4 to diffuse zinc into the copper coat and alloy it. And so. At this time, the temperature inside the heat treatment tube 4 is set to about 680'C, and about 1500 cc/g of nitrogen gas is added as an inert gas.
While flowing at a rate of 1000 C/min, hydrogen gas was introduced from the introduction pipe 7 as a reducing gas at a rate of 1000 C/min.

The obtained brass-coated carbon fiber has an average coating thickness of about 1.5 mm.
It was 3 μm thick, contained about 19% zinc in the coating, and had a golden color.

Effects of the Invention This invention utilizes fibers coated with copper and zinc in layers.
Since the method involves heating to 1050'C to diffuse zinc into the copper coating and alloying the copper and zinc to form brass, it is necessary to use a hazardous cyanide plating bath as in conventional methods. Not only does it not cause safety and health problems, it also eliminates the need to pay attention to waste liquid treatment. In addition, there are problems with so-called one-sided coating such as thermal spraying, and J:
There is no need to worry about dezincification, and manufacturing conditions can be set easily.
Since it is relatively easy to maintain over a long period of time, it has a uniform composition,
And fibers with uniform brass coating can be obtained.

[Brief explanation of drawings]

The drawings are process diagrams of the method of this invention. 1: Bobbin 2: Copper/zinc coated fiber 3: Heating furnace 4: Heat treatment tube 5: Inert gas introduction pipe 6: Inert gas introduction pipe 7: Reducing gas introduction pipe 8: Brass coated fiber 9: Bobbin

Claims (1)

[Claims] A fiber coated with copper and zinc in layers is heated to 400 to 1050°C to diffuse zinc into the copper and alloy the copper and zinc to form brass, thereby forming a brass coating on the fiber. A method for producing brass-coated fiber.