JPS6241105B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing plastic molded articles having both excellent surface hardness and metallic appearance.

It is well known that in order to give a plastic molded product a metallic appearance, a thin layer of metal is formed on the outer surface of the plastic molded product by methods such as vacuum evaporation, sputtering, and ion plating. The thin metal film laminated on the outer surface of the product is prone to scratches on the surface during handling due to rubbing between the molded products, which is a factor that reduces the commercial value of the molded product. .

In the present invention, acrylic resin is added to the outer surface of a material made of a pre-formed plastic molded product.
Select from one-component resins made of modified alkyd resins or ester resins, or two-component resins made of two-component urethane resins, two-component acrylic resins, or two-component epoxy resins. A coating containing a synthetic resin as a component is applied, and then this coated surface is dried and cured to form an undercoating layer consisting of a cured film of the synthetic resin, and then vacuum vapor deposition, A thin metal film is formed by a method such as sputtering or ion plating, and then a two-part acrylic resin, a two-part urethane resin, or a two-part epoxy resin is applied to the surface of the thin metal film. A paint containing a two-component resin selected from among these is applied, and then the painted surface is dried to form a cured resin film, which forms a primer layer. Diphenyl disulfide, benzoin, benzyl Alternatively, a high degree of cross-linking can be introduced by applying a resin paint containing a photosensitizer such as benzoin methyl ether and having the ability to form a transparent hard film, followed by ultraviolet irradiation treatment. By using a method for manufacturing metallized plastic molded products having a hard surface, which consists of forming a hard film with a hard surface, it is possible to reliably and mass-produce plastic molded products that have both excellent surface hardness and metallic appearance. It provides a way to obtain

The specific structure of the method for manufacturing a metallized plastic molded article of the present invention will be explained below based on the illustrated embodiments.

The figure shows a plastic molded product obtained when the method of the present invention is applied to a container-shaped plastic molded product made of thermoplastic synthetic resin as the material. Figure 1 is a front view of a container-shaped plastic molded product that is a metallized plastic molded product with a hard surface, and Figure 2 is a partially enlarged view of the container body of the container-shaped plastic molded product shown in Figure 1. FIG.

Metalized plastic molded product with hard surface 1
The container has a container shape consisting of a container opening 2, a container body 3, and a bottom 4, and the container body 3 and bottom 4 are formed by a layered structure as shown in FIG. There is.

That is, the layer structure of the container body 3 and bottom 4 is as follows:
A thin metal film 7 is integrally formed on the outer surface of the container wall 5 of the container-shaped plastic molded product, which is the raw material, with an undercoating layer 6 made of a hardened synthetic resin film. On the outer surface of the layer film 7, a primer layer 8 consisting of a cured resin film made of a two-part resin selected from two-part acrylic resin, two-part urethane resin, and two-part epoxy resin is provided. The transparent cured resin film 9 into which a high degree of cross-linking has been introduced is strong,
It has an integrally laminated structure.

The undercoating layer 6, which is made of a hardened synthetic resin film, is made by hardening a thin metal film 7 on the surface of the plastic molded product by vacuum evaporation, sputtering, ion plating, etc.
It is formed as a layer that is firmly and integrally bonded to both the plastic molded product and the metal thin film. Acrylic resins, modified alkyd resins, or polyester resins that have an affinity for both materials made of plastic molded products made of resins, phenolic resins, melamine resins, polyethylene resins, polypropylene resins, etc., and thin metal films. It is formed using a one-component resin, a two-component polyurethane resin, a two-component acrylic resin, or a two-component epoxy resin.

The container-shaped plastic molded article 1 constructed as described above has a thin metal coating 7 coated with a transparent cured resin coating 9 on the outer surfaces of the container body 3 and bottom 4 to form a strong and integral structure. Since the metal thin film 7 has a laminated structure, when viewed by the viewer through the transparent cured resin film 9, it has a metallic appearance, and its surface has excellent surface hardness. It's summery.

In the above, an example was shown in which a laminated structure of a thin metal film and a transparent cured resin film was applied to the entire outer surface of the container body and bottom of a container-shaped plastic molded product. It is also possible to apply a laminated structure of a thin metal coating and a transparent cured resin coating partially, for example in a pattern, only to the desired outer surface of the plastic barrel molding.

A metallized plastic molded article having a hard surface in the shape of a container having the above-mentioned configuration is produced by a specific example of the method of the present invention described below.

That is, as a first step, styrene resin,
Plastic molded products are manufactured using known methods using materials such as AS resin, ABS resin, urea resin, phenol resin, melamine resin, polyethylene resin, and polypropylene resin.

In the second step, a layer of acrylic resin, modified alkyd resin, or ester resin is applied to the outer surface of the container body and bottom of the container-shaped plastic molded product obtained in the first step. After applying a paint containing a synthetic resin selected from liquid resins or two-part resins such as two-part urethane resins, two-part acrylic resins, or two-part epoxy resins. This coated surface is dried and cured to form an undercoating layer consisting of a cured synthetic resin film.

As a third step, a thin film of metal such as aluminum, tin, chromium alloy, stainless steel, etc. is applied to the surface of the undercoating layer made of a hardened synthetic resin film formed in the second step,
It is formed by a method such as vacuum evaporation, sputtering, ion plating, etc., and subsequently, in the fourth step, a two-part acrylic resin containing a hardening agent is applied to the surface of the thin metal film formed in the third step. ,
Applying a paint containing a two-component resin selected from two-component urethane resins and two-component epoxy resins, and drying this by hot air drying or the like.
A primer layer made of a cured resin film made of the resin is formed.

As a fifth step, a photosensitizer such as diphenyl disulfide, benzoin, benzyl, or benzoin methyl ether is added to the surface of the primer layer formed by the cured resin film formed in the fourth step. After applying a paint made of a resin that has the ability to form a transparent hard film, the painted surface is irradiated with ultraviolet rays to form a transparent cured resin film with a high degree of crosslinking.

The structure of the method for manufacturing a metallized plastic molded article with a hard surface according to the present invention based on the illustrated embodiment is as described above, and the undercoating layer formed in the second step is formed on the plastic molded article as the raw material. This is an intermediate layer necessary to firmly and integrally laminate a thin metal film on the outer surface of the metal layer using methods such as vacuum evaporation, sputtering, or ion plating. The two-component resin cured film formed as the primer layer is a transparent cured resin film with a high degree of crosslinking that is firmly and integrally formed on the surface of the thin metal film formed in the third step. This is an intermediate layer necessary for the formation.

In addition, the resins that have both hard film-forming ability and transparent film-forming ability used in the fifth step include unsaturated polyester resins, acrylic resins, alkyd resins, epoxy resins, urethane resins, and their respective Modified resins or copolymer resins thereof are used.

Furthermore, the ultraviolet irradiation treatment in the fifth step is
A high-pressure mercury lamp, a metal halide lamp, or the like having a wavelength of about 200 to 600 nm is used.

The method for manufacturing a metallized plastic molded article having a hard surface according to the present invention has been explained above based on an example of a container-shaped plastic molded article.
The method of the present invention is not limited to such container-shaped plastic molded products, but can be applied to general-shaped plastic molded products, such as lid-shaped plastic molded products that are placed on the container-shaped plastic molded product. It is very generally applicable.

According to the method of manufacturing a metallized plastic molded article having a hard surface of the present invention, the presence of the undercoating layer makes it possible to form a thin metal film on the outer surface of the plastic molded article firmly and integrally. By interposing the primer layer, a transparent resin film with an excellent hard surface can be firmly and integrally formed on the surface of the thin metal film. A plastic molded product with high lamination strength in which a thin film and a cured resin film with a high degree of cross-linking are laminated together.
The plastic molded product has a decorative appearance similar to metal, and its surface is so hard that it will not leave any scratches even when rubbed with stainless steel wool or a sharp pencil lead of about 3H to 4H. It has the function and effect of being obtained.

In addition, the method of the present invention utilizes the curing effect of ultraviolet irradiation treatment to form the outermost resin film with a transparent hard surface, making it possible to form a cured film within a short period of time and mass production. It also has excellent functions and effects in carrying out.

[Brief explanation of the drawing]

FIG. 1 is a front view of a container-shaped plastic molded product, which is an example of a metallized plastic molded product with a hard surface obtained by the method of the present invention, and FIG. 2 is a front view of the container-shaped plastic molded product shown in FIG. FIG. 3 is a partially enlarged sectional view of the container body. 1: metallized plastic molded product with a hard surface, 2: container mouth, 3: container body, 4: bottom,
5: Container wall made of plastic molded material, 6:
Undercoating layer, 7: thin metal film,
8: Primer layer, 9: Transparent cured resin film.

Claims (1)

[Claims] 1. Apply a one-component resin made of acrylic resin, modified alkyd resin, or ester resin, or a two-component urethane resin, or two-component acrylic resin to the outer surface of a pre-formed plastic molded material. A coating containing a synthetic resin selected from a two-component type resin or a two-component epoxy resin is applied, and the coated surface is then dried and cured to form a cured coating made of the synthetic resin. After that, a thin metal film is formed on the surface of the undercoating layer by a method such as vacuum evaporation, sputtering, or ion plating. Formed by applying a paint containing a two-component resin selected from liquid acrylic resin, two-component urethane resin, and two-component epoxy resin, and then drying this coated surface. On the surface of the primer layer formed by the cured resin film,
It is characterized by applying a resin paint containing a photosensitizer such as diphenyl disulfide, benzoin, benzyl, or benzoin methyl ether and having the ability to form a transparent hard film, followed by ultraviolet irradiation treatment. A method of manufacturing a metallized plastic molded article having a hard surface.