JPS6112872A - Production of metallic plating reinforced plastic material and production of lightweight waveguide - Google Patents

Abstract

PURPOSE:To obtain a reinforced plastic material having a highly adhesive metallic plating layer by dispersing metallic powder to the surface of the reinforced plastic material and curing the powder then eluting the metallic powder by an etching treatment and subjecting the surface to chemical plating. CONSTITUTION:Carbon fibers 1 are alternately laminated in the directions 0 deg. and 90 deg. and a liquid epoxy resin 3 dispersed therein with Al powder 2 is coated on the surface thereof and is cured to form the reinforced plastic material. The above-mentioned material is etched by a hydrochloric acid soln. to elute the Al powder 2 on the surface and to form fine pores 4 on the surface; in succession, the surface is subjected to a hydrophiling and activating treatment, then to chemical copper plating by the conventional method to form a copper plating layer 5. Al particles 12 are dispersed to the outside peripheral surface of a molding die 11 if necessary and after the material 13 is molded by utilizing the above-mentioned method, the molding is removed from the die and a chemical plating layer 15 is formed on the inside surface by the procedure similar to the above-mentioned procedure, by which the lightweight waveguide is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a method of manufacturing a metal-plated reinforced plastic material and a method of manufacturing a lightweight waveguide.

[Technical background of the invention and its problems]

When a metal layer is coated on the surface of a plastic material, (a)
Compared to metals, it has many advantages such as being lighter, (b) imparting electrical conductivity, (c) improving weather resistance, and (d) reducing water absorption.
It is widely used in automobile parts, various industrial products, and household goods. Electroless chemical plating is used to coat the surface of the plastic material with a metal layer in this way.

In this plating technology, etching performed as a pretreatment step on the surface of the plastic material is important, and it is no exaggeration to say that this determines the adhesion strength of the plating layer.

Taking the case of ABS resin, which has been commonly used in the past, as an example, pAB
The butadiene rubber part of the S resin is relatively easily eluted,
Pore generation, hydrophilization and activation on the plastic surface occur simultaneously. In the subsequent plating process, the above-mentioned pores in particular serve as an anchor effect to improve the adhesion between the plastic and the plating layer, thereby improving the adhesion strength of the plating layer.

By the way, high-strength, lightweight materials are required for industrial robots, artificial satellites, etc., and for example, reinforced plastic reinforced with carbon fiber (hereinafter abbreviated as CFRP) is often used. Epoxy resin, which has excellent mechanical and thermal properties, is generally used as a matrix for such reinforced plastics.

However, unlike the butadiene rubber part in ABS resin, epoxy resin does not have a component that can be selectively eluted by etching, so the above-mentioned plating technology cannot be applied as is, or even if it can be applied, the plating layer has sufficient adhesion strength. The disadvantage is that it cannot be obtained.

Various types of waveguides, such as slit waveguide antennas for aerospace applications such as artificial satellites, and horn-shaped waveguides, are known as CFPRs whose surfaces are plated with metal. Since these waveguides are hollow bodies, from the viewpoints of weight reduction, manufacturing process reduction, and reliability improvement, it is desirable that they have an integrally molded structure rather than a bonded structure using resin or a joint structure using rivets or bolts.

In order to manufacture such a waveguide having an integrally molded structure, for example, U.S. Pat.
The method disclosed in No. 98 is used. In this method, an outer mold having accurate external dimensions is used, a bag-shaped inner mold that can be expanded and pressurized is placed inside, and the object to be molded is pressed from the inside to the outside.

However, the inner mold used in this method has low rigidity and is soft, making it difficult to accurately mold the inner shape.

In particular, in a waveguide having a rectangular cross section, thickness changes occur at locations where the fluidity of the resin deteriorates, such as at corners, which causes disturbances in the smoothness of the inner surface. Moreover, since waveguides require high dimensional accuracy and smoothness on their inner surfaces, finishing processing is essential after molding, but in molded products made using the above method, the reinforcing fibers are removed when forming part of the corner by mechanical polishing. This had the disadvantage that stiffness was reduced at some corners where stiffness was most needed.

[Purpose of the invention]

The present invention has been made in view of the above-mentioned concerns, and includes a method for manufacturing a reinforced plastic material having a metal plating layer formed thereon with high adhesion strength, and a method for forming a metal plating layer with high adhesion strength. The present invention aims to provide a method for manufacturing a lightweight waveguide without causing a change in wall thickness or a decrease in rigidity in the vicinity of a portion.

[Summary of the invention]

The method for manufacturing a metal-plated reinforced plastic material according to the first invention of the present application involves dispersing metal powder on the surface of a reinforced plastic material made of resin and reinforcing fibers, and after curing, etching one surface of the reinforced plastic material. The method is characterized in that the metal powder is eluted using a method of eluting the metal powder, and further chemical plating is applied.

According to this method, pores can be generated by eluting metal powder from the surface of the reinforced plastic material after hardening through etching treatment, so that the metal plating layer formed by chemical plating can be and can improve adhesion with reinforced plastic materials.

In addition, the method for manufacturing a lightweight waveguide according to the second invention of the present application is to produce a reinforced plastic made of resin and reinforcing fibers with metal particles dispersed on the outer periphery of a mold having a predetermined shape and on the surface in contact with the mold. Materials are laminated, hardened and molded, and then removed from the mold.
The inner surface of the reinforced plastic material is etched to dissolve the metal powder, and further chemical plating is applied.

According to such a method, the adhesion between the metal plating layer and the reinforced plastic material can be improved similarly to the first invention of the present application. In addition, unlike conventional methods, the mold can be made of a material that maintains sufficient rigidity at the temperature for hardening and molding reinforced plastic materials such as metals such as iron, steel, aluminum, and copper, and alloys of these materials. It is possible to eliminate the decrease in the smoothness of the inner surface, the change in wall thickness near a part of the corner, and the decrease in rigidity.

The reinforcing fibers used in the present invention include carbon fibers, glass fibers, aramid fibers, and the like.

In addition, as a metal powder, FeINircoI
Examples include metals such as At + Mf, Cr, and Zn, and alloys thereof, as long as they can be etched by etching with acid or alkali. In addition,
The size of the metal powder is preferably 10 .mu.m or less so that the pores generated by the etching process are small and uniformly distributed, and the etching can be performed at low speed without damaging the reinforcing fibers.

Furthermore, in the second invention of the present application, in order to disperse metal powder on the surface of the reinforced plastic material that comes into contact with the mold, the metal powder is dispersed in resin in advance and applied to the outer periphery of the mold, and then reinforcing fibers are laminated. Alternatively, after attaching metal powder to the outer periphery of the mold using static electricity or applying a solvent in which metal powder is dispersed, a reinforced plastic material made of resin and reinforcing fibers may be laminated.

[Embodiments of the invention]

The present invention will be explained in detail below.

Example 1 C coated with copper plating with reference to FIGS. 1(a) to (C)
A case of manufacturing an FRP laminate will be explained.

First, high modulus carbon fiber unidirectional prepreg sheet (P41
11. Toshishayo product name) 1. ...8 pieces, 0° and 9
They were laminated alternately in the 0' direction.

Next, A with an average particle size of 5 μm (maximum 10 μm)
7? S end 2. Liquid epoxy resin 3 (Epon 815 (trade name manufactured by Shell Chemical Co., Ltd.)) in which ... is dispersed at a volume ratio of 30%
:92% by weight, triethylenetetraamine (TETA)
: 8% by weight) was applied to a thickness of 15 μm. Continuing,
Curing was performed at 130°C for 3 hours using the vacuum bag method, and the size was 500mm x 500mm x 0.5911! A laminate of H was obtained (as shown in FIG. 1(a)).

The laminate was then etched with a 5N HC/solution to remove the surface AI! Powder 2. ... is eluted to form pores 4. on the surface of the laminate. ... was generated. Next, this laminate was treated with 250 r/l of chromic anhydride and 300 ml/l of sulfuric acid.
The surface was made hydrophilic and activated by immersing it in a mixed solution of 1 (50° C.) for 15 minutes (as shown in FIG. 1(b)).

Next, activation treatment of Silapray process and chemical copper plating (CP-78, trade name manufactured by Giblet Co., Ltd.) were performed according to a conventional method.
A plating treatment was performed at 48° C. for 1 hour to form a 5 μm copper plating layer 5 on the surface of the laminate (as shown in FIG. 1(C)).

Eight test pieces were cut out from the obtained laminate and subjected to a peel test using adhesive tape to examine the adhesion strength of the copper plating layer. The results are shown in Table 1 below. The Comparative Examples in Table 1 below are test results for test pieces cut from laminates treated under the same conditions as the Examples above, except that A/powder was not dispersed in the epoxy resin.

Table 1 As is clear from Table 1 above, according to the method of Example 1, it is easy to form a copper plating layer on the surface of CFRP, and its adhesion strength is also excellent.

Example 2 The case of manufacturing a lightweight waveguide will be described with reference to FIGS. 2(a) and 2(b).

First, external dimensions 40.04 x 20.04 x 300
An m+a aluminum mold 11 was prepared, and a release cloth was wrapped around its outer periphery. Next, 15 μm of liquid epoxy resin (Epon 815: 92% by weight, TERA: 8% by weight) dispersed at an A/coarse particle volume ratio of 30 μm with an average particle size of 5 μm (maximum 10 μm) was applied to the surface of the release cloth.
It was applied to a thickness of m. Subsequently, eight sheets of high modulus carbon fiber unidirectional Bripreg sheets (P4111) were laminated and wound alternately in the 06 and 90° directions.

At this stage, the outer periphery of the mold 11 is coated with A/powder 12. FRP material 13 made of epoxy resin and carbon fiber prepreg sheet in which ... is dispersed.
are layered. Furthermore, layer release cloth, bleeder cloth, and pleaser cloth on the soil and vacuum bag 14.
(as shown in Figure 2(a)).

Next, while degassing from the vacuum bag 14, the temperature was increased to 130°C.
, 4 Kg/m2 in a pressurized heating furnace for 2 hours to perform a hardening treatment (-), and then demolded to obtain a rectangular hollow body.Subsequently, this hollow body was heated with a 5N HCl! solution. etching,
A/ Powder was eluted to generate pores on the inner surface. Subsequently, this hollow body was immersed for 15 minutes in a mixed solution (50° C.) of 250 f/l of chromic anhydride and 300 ml of sulfuric acid to make the inner surface hydrophilic and activate it. Furthermore, according to the conventional method, activation treatment of Silapray process and chemical copper metal treatment @
Maturing treatment using (CP-78) (48°C, 1 hour)
was carried out to form a 5 μm entangled layer on the inner surface. Finally, silver plating was performed to manufacture a waveguide in which a metal layer 15 was formed on the inner surface of the FRP material 13 (see Fig. 2).
b) As shown).

The properties of the obtained waveguide are shown in Table 2 below.

Table 2 As is clear from Table 2 above, the waveguide obtained by the method of Example 2 has small dimensional tolerances and is strong. Also,
It is extremely lightweight and has excellent transmission characteristics. In addition, when a peeling test was conducted using the same adhesive tape as in Example 1, it was confirmed that the adhesion strength was also high.

〔Effect of the invention〕

As detailed above, according to the present invention, it is possible to obtain a reinforced plastic material on which a metal plating layer with high adhesion is formed. It is possible to provide an extremely useful method industrially, such as obtaining an excellent lightweight waveguide with no reduction in rigidity.

[Brief explanation of the drawing]

FIGS. 1(a) to (C) are explanatory diagrams showing a method for manufacturing a copper-plated C'' FRP laminate in Example 1 of the present invention, and FIGS. 2(a) and (b) are examples of the present invention. 2 is a sectional view showing a method for manufacturing a lightweight waveguide in No. 2. 1...-carbon fiber prepreg sheet, 2... AI!
Powder, 3... Epoxy resin, 4... Pore, 5...
・Copper plating layer, 1...mold, 12...A/powder,
I3...FRP material, 14...Vacuum bag, 15.
...Metal plating layer. Applicant's representative Patent attorney Takehiko Suzue Figure 1 Figure 2 (b)

Claims (2)

[Claims] (1) Distributing metal powder on the surface of a reinforced plastic material made of resin and reinforcing fibers, and after curing, etching the surface of the reinforced plastic material to elute the metal powder, and further applying chemical plating. A method for manufacturing a metal-plated reinforced plastic material. (2) A reinforced plastic material made of resin and reinforcing fibers is laminated around the outer periphery of a mold having a predetermined shape, with metal particles dispersed on the surface in contact with the mold, hardened and molded, and then removed from the mold. A method for manufacturing a lightweight waveguide, comprising etching the inner surface of a reinforced plastic material to elute the metal powder, and further applying chemical plating.