JPH0474868A - Method for plating fiber reinforced plastic structure - Google Patents

Abstract

PURPOSE:To obtain a roll excellent in smoothness and durability by applying Cu striking and Cu or Ni electroplating to the surface of a roll and finally applying hard Cr plating to the above at the time of producing a rolling roll made of fiber reinforced plastics for synthetic resin film production. CONSTITUTION:As a lightweight rolling roll for producing a film made of synthetic resin, a cylindrical body made of epoxy resin in which conductive carbon fibers are used as reinforcement and wound into plural layers is subjected to surface roughening by means of sand blasting and, simultaneously, the wound carbon fibers are allowed to appear. Subsequently, this surface is degreased and cleaned, and then, Cu striking is applied to the above surface to 1-10 mum thickness and further Cu or Ni electroplating is applied to the above. After the plated surface is polished, this surface is electroplated with hard Cr plating layer, followed by surface polishing, if necessary. By this method, the rolling roll made of fiber reinforced plastics having smooth surface, free from scratching at the surface of synthetic resin film, and excellent in durability can be produced.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention This invention relates generally to a method for plating fiber reinforced plastic/plastic structures, and more particularly to a method for plating fiber reinforced plastic rolls.

Problems with the Prior Art Metal rolls have been used interchangeably for many years in the manufacture of synthetic resin films and the like. Various characteristics are required of such rolls. For example, the film should have good followability as it travels, and the roll should have little deflection or wear.
In addition, the roll surface has excellent smoothness and the coefficient of thermal expansion is low.

This includes preventing the roll from being charged or discharging electricity that occurs as the film runs.

In response to such demands, lightweight rolls made of aluminum have been used to reduce the weight of the roll material, and attempts have been made to develop rolls using fiber-reinforced plastic to further reduce the weight.

For example, JP-A-50-56331 discloses that a film of a conductive composition is coated on the surface of a fiber-reinforced plastic structure (5 to 100 parts of a conjugated diene elastomer composition, carbon Black (a) 5-1
25 parts, metal powder (b) 0 to 110 parts, where a+b=
forming a film of a composition consisting of 20-150 parts of
A method is disclosed in which the film is cured at a temperature of 0° C. or lower to become conductive, the surface of the film is roughened by polishing, and then electroplated directly.

Furthermore, in JP-A No. 61-194197, the surface of a cylindrical object made of a composite material containing carbon fiber tow is coated from the inner layer with a conductive treatment material layer, a copper or nickel layer, and a hard chromium layer. I will reveal Laura who is there.

In these known documents, although carbon fiber reinforced resin is used, a conductive film is formed by applying a resin composition containing conductive powder such as carbon powder, metal powder, or silver powder to the surface of the structure. is formed, and plating is performed on it. The second point shows the technical difficulty of directly plating the surface of the carbon fiber reinforced resin.

Although the above-mentioned plating method has brought about some results in reducing the weight of the roll, there are the following problems regarding plating on the conductive layer.

1. When polishing the surface of a fiber-reinforced resin structure in pretreatment for forming a conductive film, the brittleness of the resin tends to cause partial destruction of the surface, falling off, and partial breakage of the carbon fibers.

2. When forming a 30 μm conductive film on a surface roughened by polishing, it is difficult to form the conductive film with a uniform thickness. : It is difficult to homogenize the conductive material in the shaded conductive film.

3. Regarding the amount of conductive material added in the cloth material for forming the conductive layer, the larger the ratio of the conductive material, the more the conductivity increases or the strength of the coating film decreases.

become brittle. Therefore, the addition of conductive material is usually 10 to 30%.
Generally speaking, it is considered as a degree. In this case, carbon fiber is 50~
The conductivity is inferior to that of reinforcing fibers, which account for 55%, and high-density plating cannot be obtained.

4. It takes a long time to dry the conductive film.

5. It is difficult to homogenize the distribution of conductive powder in the conductive film.

6. As a result of 1 to 3 above, durable and good plating cannot be obtained.

All of these problems lead to high costs, and the strength of the final plating layer and the finish of the plating surface do not reach a satisfactory level compared to conventional aluminum roll plating products. child .

Means for Solving the Problems The present applicant has completed the present invention as a result of intensive research to solve the above problems.

According to the present invention, the surface of a structure formed from a resin composite material reinforced with high-density conductive fibers is exposed by sandblasting, and the surface is roughened.
After that, the surface is degreased and washed, and a copper plating layer of 1-10 μm is applied directly to the surface by strike plating using a plating bath with a special composition and plating conditions, and then plated to a desired thickness by electrolytic copper plating or electrolytic nickel plating. A layer is formed and the surface is polished as necessary, for example, to a surface roughness of 0°2.
~0.85), a hard chrome plating layer of a desired thickness is formed by post-electrolytic hard chrome plating, and the surface is polished as necessary to obtain a desired surface roughness.

Function The sandblasting process allows the roughness of the base material surface to be adjusted appropriately, and the conductive fibers are fully exposed without being destroyed to an extreme extent, increasing the electrodeposition area, and the strike plating achieves high adhesion to the base material. After securing the strength, apply copper or nickel plating and polish as necessary to achieve the desired smoothness (roughness), then apply hard chrome plating and polish as necessary. Provides sufficient surface hardness.

It has smoothness and can form a durable layer.

The present invention has been outlined above, and in order to better understand the present invention, the present invention will be further described in detail through examples of the present invention.

Example A commercially available roll made of ebony/resin reinforced with a cylindrical structure made of multiple layers of highly densely wound carbon fiber (manufactured by Takunen Co., Ltd., outer diameter 100 mm, length 1800 mm) was prepared. ,
The roll surface is roughened by sandblasting. The blasting material, the air pressure for spraying, the diameter of the injection nozzle, etc. are appropriately selected within the conventional range (for example, blasting materials: emery, silica sand, grisotho, etc.).
Air pressure crab 3Kg/cm"-
3K g/cm”, injection nozzle diameter: 5mm-1
0 mm, particle size: 100-250 mm). I tried various methods of sandblasting by changing the sandblasting conditions, and found that even if the sandblasting was insufficient, it was too much, and it greatly affected the results of the subsequent strike plating process. Desirable sandblasting is to make the resin surface on the material surface into a finely roughened surface, and to fully expose the conductive fibers on the surface to increase the conductive surface as much as possible, or to limit the conductivity to such an extent that the conductive fibers themselves are not destroyed. It turned out to be something important. Therefore, the blasting conditions need to be appropriately selected in consideration of the structure of the target material (fiber count, twist state, winding method, type of resin, impregnation state, etc.).

After blasting, the surface of the structure is degreased using conventional methods.

Washed.

Next, a copper plating layer with a thickness of 5 μm was formed by strike copper plating. In the present invention, copper cyanide 30~
60 g/Q, sodium chloride 5-15 g/Q, free sodium chloride 5-10 g/Q.

Using a plating bath (pH 12 or higher) with a composition of caustic potassium 5 to 10g/Q, plating bath temperature 55 to 75°C, working voltage 10
~15V, current 15-20A, anode-cathode distance 3-5 times the standard distance. The above-mentioned preliminary treatment by sandblasting, the above-mentioned special plating bath composition, high temperature plating bath, and high voltage.

By employing strike plating with a high current density and a distance between electrodes that is 3 to 5 times the normal distance, it has become possible to achieve plating with extremely good adhesion. The distance between the electrodes varies depending on the shape of the structure to be plated. In the composition of the strike plating bath in the present invention, the ratio of copper chloride to sodium dianide was reversed to significantly increase the concentration of copper cyanide, which is a supply source of copper ions. Free sodium cyanide may be adjusted depending on the situation. The plating bath temperature is 55 to 75°C or appropriate;
When the bath temperature is high, it becomes easier to conduct electricity and the dissolution of the anode is promoted, so it is carried out at a high temperature unless there is a problem. MaI;
Increasing the working voltage improves the adhesion, but with a normal cathode-anode distance (D), the current increases and "burning" occurs during energization. Therefore, in the present invention, the distance between the cathode and the anode is set to be 3 to 5 times the normal distance.

It is necessary to adjust the plating conditions for strike plating within the above-mentioned range depending on the surface condition and shape of the material 7 of the object to be plated. The film thickness formed is at least 3-5μ
Should it be m? Is there any particular upper limit to the film thickness?
It is meaningless to form more than opm. Strike copper plating can be applied not only to cyanide plating but also to copper pyrophosphate plating.

When acid copper plating is applied to metal materials such as chromium, iron, cadmium, nickel, etc., since copper is lower in the potential series than these metals, the material metals immersed in the acidic copper plating bath ionize and dissolve. However, since copper precipitates on top of it, plating with good adhesion cannot be achieved.

On the other hand, the strike plating in the present invention uses a special cyan-based plating bath as mentioned above, and the distance between the anode and cathode is larger than that of conventional strike plating, resulting in high temperatures, high voltages, and high By using an electric current, a plating layer can be formed instantaneously and over the entire surface. Since the copper ion density in the plating bath of the present invention is extremely low, plating with extremely good adhesion is possible.

A copper plating layer having a desired thickness (for example, 300 μm) is formed on the strike plating layer thus formed by electrolytic plating. Electrolytic plating force conditions may be standard. The formed electroplated layer is polished according to a conventional method to a desired surface roughness (for example, 0.65), if necessary.

Next, a 100 μm plating layer was formed by electrolytic hard chrome plating, and if necessary, final polishing was performed by a conventional method to a desired surface roughness (for example, 0.23).

As a result of the above, the surface roughness is 0.23. Surface hardness is 900~
A plated roll with excellent wear resistance and peel strength was obtained at 950HV. At first glance, it was apparent to those skilled in the art that this product had superior quality compared to conventional products.

A conventional roller in which a conductive film is formed on a cylindrical body made of carbon fiber reinforced resin using paint mixed with a conductive material, a copper plating layer is formed thereon, and a hard chrome plating layer is further formed, and a roller according to the present invention. at a temperature of 120°C using
As a result of a comparative test using the product for 24 hours, only small blisters were observed in the conventional product, but no blisters were observed in the product of the present invention.

The thickness of the electrolytic copper plating layer in the present invention varies depending on the surface condition in the previous step and the degree of surface smoothness after finishing.The same applies to the thickness of the chrome plating. It is clear that the method of the invention can be used not only for producing plating rolls, but also as a method for plating other fiber-reinforced plastic structures.

Effect of the invention The effects achieved by the present invention are as follows.

Sandblasting I Therefore, by finely roughening the material surface and exposing the conductive fibers in as wide an area as possible without destroying them, and by strike plating using a special plating bath and plating conditions, it is possible to achieve good conductivity with good adhesion. In combination with the second layer that forms the surface, there is no need to coat the surface of the material with a conductive composition, and the copper plating layer is directly formed, and the second layer is layered on top of the copper plating layer, resulting in superior durability. A storage layer can be formed.

Claims (1)

[Scope of Claims] [1] The surface of a structure formed from a resin composite material reinforced with high-density conductive fibers is sandblasted to expose the conductive fibers and to roughen the surface, and then,
Degrease and clean the surface, form a copper plating layer of 1 to 10 μm directly on the surface by strike plating, then form a plating layer of the desired thickness by electrolytic copper plating or electrolytic nickel plating, as necessary. A method for plating a fiber-reinforced plastic structure, which comprises polishing the surface, forming a hard chrome plating layer of a desired thickness by electrolytic hard chromium plating, and polishing the surface if necessary. [2] In the plating method according to claim 1, the strike plating includes 30 to 60 g/l of copper cyanide, 5 to 15 g/l of sodium cyanide, and 5 to 1 g/l of free sodium cyanide.
Plating bath with a composition of 0 g/l and 5 to 10 g/l of caustic potassium (
A fiber-reinforced plastic characterized by plating at a plating bath temperature of 55 to 75°C, a working voltage of 10 to 15 V, a current of 15 to 20 A, and an anode-cathode distance of 3 to 5 times the standard distance. Structure plating method.