JPH0351202B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a mold release agent for metal thermal spraying. More specifically, the present invention relates to a mold release agent for metal thermal spraying that has excellent metal adhesion and is easy to demold when metal thermal spraying is performed.

When forming a resin molded product using a mold, a metal film is formed on the mold in advance by metal spraying, and then the metal film is backed up using a resin molding material to integrate the metal film and the resin molded product. A method has been proposed for manufacturing a metal-resin composite in which a metal film and a resin molded product are integrated by pressing and then demolding. If this method is followed, a metal-resin composite with a metal layer firmly attached to the surface can be manufactured easily and with good dimensional accuracy, and the resin molded product can be endowed with various physical properties such as wear resistance, electrical conductivity, and heat resistance. It is considered to be a very useful method because it can be done.

However, when performing metal spraying on a mold, if no mold release agent is used on the mold surface, a problem tends to occur in that the sprayed metal hardly adheres to the mold surface. Furthermore, as already proposed, if a solution of polyvinyl alcohol is applied as a mold release agent and then dried, followed by metal spraying, the adhesion of the sprayed metal will be slightly improved, but There are problems such as the deposited metal film peeling off during the work, or the fact that the sprayed metal does not adhere well to mirror-finished molds. Currently, the development of a mold release agent that allows easy molding is awaited.

The present inventors conducted various studies in view of the current situation, and as a result, arrived at the present invention. That is, the present invention provides a mold release agent used in metal thermal spraying, which contains a cationic polymer (A) in an amount of 0.001% by weight or more, and the remainder is a solvent (B) that dissolves or disperses the cationic polymer (A). This is what we provide.

The cationic polymer (A) used in the present invention is
It is a water-soluble or water-dispersible polymer that is composed of polyalkylene polyamines such as polyethyleneimine and polypropyleneimine and/or derivatives thereof, and has cationic nitrogen in the molecule. As derivatives of polyalkylene polyamines, for polyalkylene polyamines, polycarboxylic acids, polyglycidyl compounds such as epoxy resins, polyisocyanate compounds such as urethane prepolymers, polymers containing chloromethyl groups and/or hydroxymethyl groups, and , polyhaloalkane, and/or epihalohydrin and/or polyepihalohydrin.

Any of these polymers can be synthesized by a conventional method. These polymers may be used as they are, or a part of the cationic nitrogen contained in these polymers may be salted with an inorganic or organic acid such as hydrochloric acid, phosphoric acid, formic acid, or acetic acid, or a quaternary It can also be used as an ammonium salt.

As the cationic polymer (A), one or more of these polymers can be used.

The solvent (B) is a solvent that can completely or largely dissolve or disperse the cationic polymer (A), and after applying the mold release agent to the mold, it can be used at room temperature or at a heated temperature. It transpires. Therefore, the solvent (B) may be appropriately selected depending on the temperature of the mold to be coated. For example, a single solvent or a mixture of two or more of water, methyl alcohol, ethyl alcohol, isopropyl alcohol, acetone, ethyl acetate, butyl acetate, ethylene glycol, propylene glycol, diethylene glycol, methyl cellosolve, dimethyl sulfoxide, etc. It is desirable to use a low boiling point solvent when using a low temperature type, and a high boiling point solvent when using a high temperature type.

The amount of cationic polymer (A) is 0.001% by weight or more in the mold release agent obtained.

If the amount of cationic polymer (A) is less than 0.001% by weight, the adhesion of the sprayed metal will be poor, and problems such as hardly any metal film will be formed or the metal film will peel off during the spraying process. This is not preferable as it tends to occur. Cationic polymer (A)
There is no particular restriction on the upper limit of the amount used, and it is used within a range until work becomes difficult due to increased viscosity as the amount used increases.

In order to obtain the mold release agent for metal thermal spraying of the present invention from the cationic polymer (A) and the solvent (B), these components may be mixed using a conventional mixing method and apparatus, and there are no particular restrictions on the mixing order. There isn't.

Moreover, other additives can be used in the mold release agent for metal thermal spraying of the present invention as necessary. For example, it is also possible to add a water-soluble coloring agent for coloring.

When using the mold release agent for metal thermal spraying of the present invention, the mold release agent is applied onto the mold surface by means such as a brush, sponge, or spray, and then dried to form a film on the mold surface. That's fine. Moreover, it is also possible to apply a mold release agent generally used for mold release of resin molded products to the mold surface in advance so that the mold release agent can be easily applied uniformly onto the mold surface. If a film of the mold release agent for metal spraying according to the present invention is formed on the mold surface in this manner and then metal spraying is performed on the film, the adhesion of the sprayed metal will be good and it will not peel off during the spraying process. Alternatively, it is possible to form a good metal film without causing problems such as falling off. In addition, it is easy to back up the metal film obtained in this way with a resin molding material, integrate the metal film and the resin molded product, and then remove the resulting metal-resin composite from the mold. can be done.

The mold release agent of the present invention remaining on the mold surface or the metal surface of the metal-resin composite after demolding can be easily removed by washing with water.

Hereinafter, the present invention will be explained in more detail with reference to Examples and Comparative Examples. Note that all parts in the examples indicate parts by weight.

Example 1 Epoxidized polybutadiene with a molecular weight of about 1000 (trade name "BF-1000", manufactured by Adeka Argus) and polyethyleneimine with a molecular weight of 300 (trade name "Epomin")
SP-003'' (manufactured by Nippon Shokubai Kagaku Kogyo Co., Ltd.) and neutralized with hydrochloric acid to remove cationic nitrogen.
A cationic water-dispersible polymer (PH2.0, solid content 20%) containing 2.3 mmol/g was obtained. 10 parts of this cationic water-dispersible polymer was dissolved in a solvent consisting of 100 parts of water and 50 parts of ethyl acetate to obtain a mold release agent for metal thermal spraying (hereinafter referred to as mold release agent (1)). This mold release agent (1) was applied thinly to the surface of a flat FRP mold using a brush and left to dry at room temperature for 30 minutes. Next, an arc spraying machine (manufactured by TAFA, USA,
When zinc was thermally sprayed to a thickness of approximately 100 microns using 375EFS), a good metal coating was obtained. next,
Unsaturated polyester resin (manufactured by Nippon Shokubai Chemical Co., Ltd., Eporak G-773PTMY) was applied on the obtained thermal spray coating.
55 parts of methyl ethyl ketone peroxide to 100 parts
% dimethyl phthalate solution and glass matte (manufactured by Nitto Boseki Co., Ltd.,
MC-450A) was laminated to a thickness of about 5 mm by the hand lay-up method on the metal film described above according to a conventional method, and then left at room temperature to harden.
Next, when the metal layer was demolded together with the hardened FRP, it could be easily demolded and the surface condition was good.

Comparative Example 1 In the same flat FRP mold used in Example 1,
When zinc was directly sprayed under the same conditions as in Example 1 without using a mold release agent, the sprayed zinc did not adhere.

Comparative Example 2 Polyvinyl alcohol (Nippon Gosei Chemical Industry Co., Ltd.)
Gohsenol GH-23) 50 parts and 400 parts of water at 90℃
After dissolving in 50% of methanol, cool to room temperature and add 200% of methanol.
and 50 parts of ethyl acetate to obtain a mold release agent (hereinafter referred to as mold release agent (2)). The mold release agent (2) was applied to the same mold used in Example 1 under the same conditions as Example 1, and then dried, and then zinc was sprayed under the same conditions as Example 1. During the process, the sprayed metal film peeled off from the mold.

Claims (1)

[Claims] 1 0.001 cationic polymer (A) consisting of polyalkylene polyamine and/or its derivative
A mold release agent for metal thermal spraying, which contains at least % by weight, with the remainder mainly consisting of a solvent (B) that dissolves or disperses the cationic polymer (A).