JPH02129380A - Production of copper plated resin molded product - Google Patents

Abstract

PURPOSE:To obtain a resin molded product with a high quality Cu film formed by a simple method by adhering copper formate to the desired part of a resin molded product having a high deformation or deterioration temp. and heating and holding the product at a prescribed temp. CONSTITUTION:A soln. contg. dissolved or dispersed copper formate is applied to the desired part of a resin molded product of polyamide, etc., having a high deformation or deterioration temp. of >=165 deg.C The product is heated to a prescribed temp. between 165 deg.C and the deformation or deterioration temp. at >=1 deg.C/min heating rate in the temp. range of 130 deg.C to the prescribed temp. In a nonoxidizing atmosphere or under reduced pressure and the heated product is held at the prescribed temp. The proper amt. of copper formate adhered is >=0.005g/cm<2>. The product is then cooled to room temp. and a Cu plating film is formed on the desired part. Cu powder produced from copper formate not concerned in film formation is removed by slight wiping or other method and anticorrosive treatment is carried out as required.

Description

Detailed Description of the Invention [Industrial Field of Application] The present invention provides a method for applying a uniform copper coating to a heat-resistant fiber-reinforced or unreinforced thermoplastic or thermosetting resin molded product having a heat deformation deterioration temperature higher than 165°C. The copper-plated molded products produced by this manufacturing method have copper firmly and uniformly adhered to grooves, holes, etc. without any special pretreatment, and are free from halogens, etc. Since it does not contain any corrosive elements, it can be suitably used for various purposes either as it is or as a base for plating with copper or other metals.

[Conventional technology and its issues]

Generally, methods for forming a copper coating on a thermoplastic resin molded product include electroless plating, vapor deposition, pressure welding, bonding with adhesives, and the like.

Electroless plating is the most common method and is an excellent method because low-temperature plating is possible, but it usually requires special pretreatment. In order to omit or simplify this pretreatment step, there is a method of using a molded article made from a composition that has been blended with diene rubber or the like in advance, but this often results in deterioration of the inherent performance of the resin. In addition, in the case of resin molded products containing reinforcing materials such as glass fiber, it is difficult to plate the surface of the reinforcing material with good adhesion at the same time, so it is difficult to plate the reinforcing material on the surface of the molded product where the reinforcing material is exposed. It had drawbacks such as easy peeling.

The vapor deposition method requires special equipment for vapor deposition, and depending on the type of article, pretreatment is required to improve adhesiveness. Furthermore, pressure bonding methods and bonding with adhesives are used as appropriate, but if pressure bonding is not possible, the shape of the molded product is limited, or if adhesives are used, the adhesive layer becomes thicker and the adhesive layer becomes thinner. This method has disadvantages such as deterioration of the physical properties of the article obtained.

Furthermore, it is known that when copper formate is applied to an article and heat treated in a non-oxidizing atmosphere, an article with a copper coating can be obtained. However, there have been no examples of applying this method to molded products of thermoplastic resins or thermosetting resins, and there is also no method suitable for mass production, so it has not been put to practical use.

[Means to solve the problem]

In view of the above circumstances, the present invention was completed as a result of studies on a method of providing an economical and high-quality resin molded product with a copper film formed thereon by a simple method.

That is, the present invention applies a solution in which copper formate is dissolved or dispersed to a desired part of a resin molded product whose deformation deterioration temperature is higher than 165°C, and dries it at a temperature of 130°C or lower to adhere the copper formate. The temperature is raised to a predetermined temperature in the range of 165 °C or higher and below the deformation deterioration temperature of the molded product in a neutral atmosphere or under reduced pressure, and then held at a rate of Ideg/min or more between the temperature of 130 °C and the predetermined temperature. This is a manufacturing method for copper-plated resin molded products, which is characterized by the fact that the amount of copper formate deposited is 0.005 g/cd or more, and that anhydrous copper formate powder is used as the solution of copper formate in an organic solvent with a boiling point of 200°C or less. using a solution dispersed in copper formate, coexisting additional copper formate in the vicinity of the molded product to which copper formate is attached, and storing a large number of the molded products to which copper formate is attached in a container, or This is a method of manufacturing a copper-plated resin molded product, which consists of placing it in a placement tool and heat-treating it.

The present invention will be explained below.

The resin molded products of the present invention whose deformation deterioration temperature is higher than 165°C are usually injection molding, compression molding, transfer molding,
It is usually a three-dimensional molded product formed by other means, having grooves, holes, etc., and is made of heat-resistant thermoplastic resin or thermosetting resin.

Examples of thermoplastic resins include nylon-6, nylon-66, nylon-6/66, nylon-11, nylon-3, MXD6 and MXD6/10 derived from metaxylylene diamine and aliphatic dicarboxylic acids. General-purpose engineering plastic necks such as crystalline polyester resins such as polyamide resin, polybutylene terephthalate, and polyethylene terephthalate; wholly aromatic polyesters whose main monomers are P-hydroxybenzoic acid, phthalic acid, bisphenol, etc., and grafts of polyethylene terephthalate, etc. to these Engineering plastics such as aromatic polyester liquid crystal polymers, polyetherimide, polysulfone, polysulfone, polyethersulfone, polyetheretherketone, polyphenylene ether, polyphenylene sulfide, and fibers, minerals, and other filler reinforcements of these polymers Among these, those having the above-mentioned deformation deterioration temperature of 190° C. or higher are preferable, and are particularly suitable for fiber-reinforced ones. Further, as the thermosetting resin, phenol resin, diallyl phthalate resin, epoxy resin, polyamine-bismaleimide resin, polymaleimide-epoxy resin, polymaleimide-isocyanate resin, cyanato resin, cyanate-epoxy resin,
Common thermosetting resins such as cyanate-polymaleimide resin and cyanate-epoxy-polymaleimide resin: the above thermosetting resins and polyamide (nylon), aromatic polyester, polyetherimide, polyetheretherketone, polysulfone , polyphenylene ether, and other engineering plastics, and further appropriate catalysts are added. Crosslinked curable resins made by blending peroxides, radically polymerizable polyfunctional compounds, thermosetting resins, etc., as well as glass, carbon, alumina, other fibers, and woven fibers. , powder, and reinforced materials containing other fillers.

The solution in which copper formate is dissolved or dispersed according to the present invention is a solution in which a cupric formate compound such as anhydrous copper formate, copper formate tetrahydrate, or a mixture thereof is dissolved in a relatively low boiling point solvent that does not substantially react with copper formate. It is a solution in which dissolved or powder is uniformly dispersed. Suitable solvents include water, alcohol, aliphatic hydrocarbons, aromatic hydrocarbons, and other suitable solvents with a boiling point of 200°C or less. In particular, formic anhydride In the case of copper, a dispersion solution is prepared by kneading a water-free organic solvent such as heptane, hexane, cyclohexane, octane, propatool, butanol, heptatool, benzene, toluene, xylene, etc. with fine copper formate powder. It is preferable to use Note that when used in the same manner as printing ink compositions, etc., a method of selecting a solvent with a higher boiling point and drying under reduced pressure can also be used.

The above-mentioned copper formate solution is applied to a desired part of the above-mentioned molded article, dried, and allowed to adhere. Examples of the coating method include brush coating, dipping, spray coating, bar coding, roll coating, printing, and other coating methods, and drying is carried out at a temperature below the decomposition temperature of copper formate, usually below 130°C, especially below 110°C.
Dry by heating or under reduced pressure at the following temperature. Here, it is sufficient that the copper formate adheres to substantially the entire desired surface, and slight variations do not pose a particular problem. For example, even if grooves, holes, etc. are blocked by copper formate powder or crystals, a copper film of less than 10% will normally form on the wall surface of the grooves, holes, etc., and will not block the grooves, holes, etc. It's something that doesn't exist.

In addition, if you want to plate copper on a part of the molded product instead of the entire surface, you can apply it only to the desired part, or cover the parts other than the desired part with a removable resist, then apply it to the entire surface, or use it as is or with Depends on how you peel it off.

The copper formate-adhered molded product obtained above is heated to a predetermined temperature in the range of 165°C or higher and below the deformation deterioration temperature of the molded product in a non-oxidizing atmosphere or under reduced pressure, and then heated by 1 deg between the temperature of 130°C and the predetermined temperature. By raising and maintaining the temperature at a rate of 1 minute or more,
Obtain a copper plated molded product.

As the heating device, radiation heating such as infrared rays, electron beams, microwaves, etc., electric furnace, oven, oil heating, pressurized steam heating, and other means are appropriately selected. It may be a batch type or a continuous type heating machine having an introduction part, a heating part, and a cooling takeout part for the article to be heated. Further, depending on the deformation deterioration temperature of the resin molded product, the heat treatment temperature and the deformation deterioration temperature may be close to each other, so the set temperature should have small variations.

The heating method is to heat the molded article at a predetermined temperature in the range of 165°C or higher and below the deformation deterioration temperature of the molded product under a substantially non-oxidizing atmosphere or under reduced pressure, and to heat the molded product at 1 deg/deg between the temperature of 130°C and the predetermined temperature.
There is no particular limitation, except that the temperature is raised and maintained at a rate of 1 minute or more, but a heating device has a heating plate as a heating section that is set at a predetermined temperature in the range of 165°C or higher and below the deformation deterioration temperature of the molded product. The heating rate can be increased using the method of charging Further, it is preferable to heat at a heating rate of 1 to b and maintain the temperature at the same temperature. Also, the heating time is 3
It is preferably 1 to 60 minutes.

If the heating rate is less than 1°C/min, it is undesirable because the resulting plating film is likely to be non-uniform or the adhesive strength will be poor; if it is too fast, this will occur when processing a large number of molded products at the same time. Copper plating is also formed continuously on the contact portions, which is undesirable because it prevents the production of copper powder for isolating the contact portions.

A known method for creating a non-oxidizing atmosphere is N2. Ar.

Examples include a method of introducing a gas such as CD□, CD, 82, etc., and a method of reducing the volume inside the heating device containing the molded product to create a substantially decomposed gas atmosphere of copper formate, especially for continuous heating devices. When using a heating section, by reducing the opening area of the inlet and outlet to the heating section, the decomposed gas atmosphere can be easily maintained without using an inert gas. In addition, methods for reducing the pressure include using a heater that can reduce the pressure, storing the molded product to be plated in a container that can reduce the pressure, and reducing the pressure only in the container, or especially using continuous heating equipment. An example is a method of arranging a decompression chamber at the introduction part and the takeout part, and the degree of decompression is preferably 400 Torr or less, particularly 200 Torr or less.

The copper-plated molded product of the present invention is manufactured by the above method, but as mentioned above, in the present invention, a container or placement tool for storing and heat-treating the resin molded product to which copper formate is attached is used. This method is preferable because it increases the efficiency of loading and unloading resin molded articles to be plated into heating equipment and reduces unevenness in plating conditions, and is particularly suitable for commercial mass production.

Here, the containers and placement tools mentioned above may be made of metal, resin, or other materials without particular limitation as long as they are made of a material that can withstand processing temperatures, but are usually made of aluminum, iron, copper, or other metals. It is. The optimal shape of the container or arrangement tool is selected or designed as appropriate, depending on the shape of the molded product and the heating equipment used, so that multiple molded products can be arranged more densely and loading and unloading operations are facilitated. . Although it is not necessarily necessary in the case of the above-mentioned preferred method using a volatile organic solvent dispersion of anhydrous copper formate powder, depending on the shape of the molded product, especially the height, it may be necessary to It is preferable to provide an additional formic acid copper arrangement section in the upper part and arrange the copper formate there, since variation in plating thickness between the top and bottom can be further reduced.

After heat treatment using the above method, the product is cooled to room temperature to produce a copper-plated molded product in which the desired parts are copper-plated and the contact parts are isolated with copper powder produced from copper formate that did not participate in film formation. obtain. This copper powder can be easily removed by gently wiping the molded product, blowing air on it, or other means.

The copper-plated molded product taken out is subjected to a known anti-corrosion treatment if necessary, and is further subjected to known electroless plating or electrolytic plating of copper, nickel, gold, or other metals as appropriate.

If this excess copper powder is not generated, it is essential to take special measures to isolate the molded products from each other and between the molded products and containers or auxiliary tools. This method requires a large amount of manpower or requires processing two or more times, and is a necessary advantage in terms of productivity.

〔Example〕

Hereinafter, the present invention will be explained in more detail with reference to Examples and Comparative Examples. In addition, parts in Examples and Comparative Examples are based on weight unless otherwise specified.

Example 1 100 parts of anhydrous copper formate powder and 50 parts of butyl alcohol were kneaded to obtain a dispersion solution (hereinafter referred to as treatment liquid 1) in which the anhydrous copper formate powder was uniformly dispersed.

Thickness 3ITl obtained by injection molding of nylon MXD6 from carbon fiber reinforced metaxylylene diamine and adipic acid
[I+1 A slightly curved glasses frame molded product with a width of 140+nm and a height of 55+nm was used, and after applying treatment liquid 1 to this molded product, it was dried at 100° C. to adhere anhydrous copper formate to the entire surface.

Prepare a box made of aluminum with a lid of 200 mm in length, 300 nm in width, and 55 nm in height and equipped with a nozzle with a cock for gas injection and discharge on the side, and place 30 of the glasses frames obtained above in this box. After placing the pieces in storage and arranging them, blowing N2 into the box from the nozzle and putting the lid on. After removing the N2 blowing vibrator, it was placed between the heating plates of a heater preheated to 230℃, which has heating plates on the top and bottom that can reduce the pressure. and set the inside of the heater to several Tor.
The pressure was reduced to r and maintained as it was for 30 minutes. Note that the temperature increase rate inside the box was 7° C./min.

The vacuum was stopped, the box was taken out, and the box was allowed to cool to room temperature to obtain copper-plated eyeglass frames.

In the resulting eyeglass frames, the copper film was uniformly adhered to the contact areas between the frames and the inner wall of the container, and there was no adhesion due to the continuity of the copper plating layer at the contact areas, and there was no adhesion in the grooves. No excessive copper film was formed, and no traces of carbon fibers were observed.

In addition, the thickness of this copper film is 0.2 to 0.5 mm, and the surface resistance is 0.
．． A cross-cut test using cellophane tape at 05 to 0.5 Ω/mouth was performed and the result was 100/100.

As a result of electrolytic copper plating using this frame, a uniform and glossy copper-plated eyeglass frame was obtained.

Example 2 In Example 1, a box with a lid similar to that in Example 1 was placed in the heater, and the lid was closed while N2 was blown into the box from the nozzle, and the inside of the heater was not reduced in pressure. A uniformly copper-plated eyeglass frame similar to Example 1 was obtained.

Example 3 A glasses frame whose entire surface was plated with copper was obtained in the same manner as in Example 1 except that an aqueous solution saturated with copper formate was used instead of the treatment liquid 1. Note that the copper plating thickness was 0.2 to 1.0 ρ, and the appearance was slightly nonuniform.

Example 4 In Example 1, instead of the glasses frame, a diameter of about 3
A gear with copper plating only on the surface was obtained in the same manner except that a gear with a diameter of 5 mm and a height of about 10 mm was used. Note that the copper plating thickness was 0.2 to 0.51.

Example 5 As a model molded product, a rectangular groove with a width of 2 mm on one side and one body,
A figure 7 groove and drilled holes of 5 mm, 3 mm and 1 hole in diameter are formed, and the other side is smooth and has a thickness of 3 mm.

A resin molded article having a width of 40 mm and a length of 145 mm described below was prepared.

The appearance of the copper film was determined by visual observation; ◯ indicates the formation of a uniformly adhered copper film, and △ indicates deformation of the molded product.

Table 1-1 In addition, as an aid for placement, an aluminum sheet with a thickness of 0.3 mm was bent, and the cross section viewed from the direction perpendicular to the folded surface had protrusions with a height of 10 cm at 5 stroke intervals. A comb-like object was prepared.

These molded products and auxiliary tools were immersed in treatment liquid 1 and dried.

Next, these molded products were prepared in Example 1 using the above-mentioned auxiliary tool.
Table 1 shows the results of placing two pieces each in a box similar to the above and plating them under the processing conditions listed in Table 1.

Table 1-2 Table 2 Example 6 The same procedure as in Example 5 was carried out except that the following thermosetting resin molded products were used in place of molded products 1 to 10. The results are shown in Table 2.

(Manufactured by Mitsubishi Gas Corporation) [Operations and Effects of the Invention] According to the manufacturing method of the present invention as described above, conventionally, adhesiveness could not be achieved by electroless plating or the like without special pretreatment. It is possible to easily produce a molded product on which a copper film with excellent adhesion is formed on a resin molded product, in which it has been difficult to form a copper film with excellent adhesion, by an extremely simple means.

Moreover, even if a large quantity is processed all at once, they are separated from each other by finely powdered copper and are not bonded together by copper plating, making it easy to produce in large quantities.

The copper plating layer of this copper-plated resin molded product can be plated with copper, nickel, chromium, silver, gold, or other materials easily and uniformly by electroplating, electroless plating, or other means, so it may be used as it is or It is suitable for use as an inexpensive base treatment for plated products.

Patent applicant: Mitsubishi Gas Chemical Co., Ltd.

Claims (1)

[Claims] 1. A solution in which copper formate is dissolved or dispersed is applied to a desired part of a resin molded product whose deformation deterioration temperature is higher than 165°C.
Copper formate is deposited by drying at a temperature of 130°C or lower, and then heated to a predetermined temperature in the range of 165°C or higher and below the deformation deterioration temperature of the molded product in a non-oxidizing atmosphere or under reduced pressure. A method for producing a copper-plated resin molded product, characterized by raising and maintaining the temperature at a rate of 1 deg/min or more. 2. The method for producing a copper-plated resin molded article according to claim 1, wherein the amount of the copper formate deposited is 0.005 g/cm^2 or more. 3. The method for producing a copper-plated resin molded article according to claim 1, wherein the solution is a solution in which anhydrous copper formate powder is dispersed in an organic solvent having a boiling point of 200° C. or less. 4. The method for producing a copper-plated resin molded article according to claim 1, wherein additional copper formate is coexisting in the vicinity of the molded article to which copper formate is attached. 5. The method for producing a copper-plated resin molded product according to claim 1, wherein a large number of the molded products to which copper formate is attached are housed in a container or placed in a placement tool and heat-treated.