JP2948852B2 - Cosmetic material for simultaneous painting with injection molding - Google Patents

Description

The present invention relates to a decorative material for simultaneous painting by injection molding.

[Problems to be solved by conventional technology and invention]

The decorative material for simultaneous painting by injection molding is generally constituted by providing a decorative layer made of a desired pattern, characters, etc. on a film base material such as polyethylene terephthalate. After mounting the mold on the inner surface of the cavity and closing the mold, injection molding is performed by injecting and filling a molten resin into the mold, and the release layer is peeled off after releasing the mold so that the decorative layer is formed on the surface. It is possible to obtain an injection molded article to which transfer adhesion has been performed, or to obtain an injection molded article in which the entire decorative material is adhered to the surface without releasing the film substrate after releasing the mold.

As described above, the cosmetic material for simultaneous injection molding is very useful because it can perform desired painting simultaneously with injection molding on an injection molded product, but since the whole is a plastic film-like material. It is easy to be charged, and as a result, dust adheres to the surface of the decorative material and causes molding failure, and the decorative material adheres to the inner surface of the mold wrinkled when it is mounted in the injection molding die. As a result, smooth mounting becomes difficult, and there is a problem that a molding wrinkle is generated in the obtained injection molded product.

In order to prevent this type of cosmetic material from being charged, conventionally, means for adsorbing moisture or ions on the surface of the decorative material has been known. However, this method is effective only at the time of adsorption and has a long lasting antistatic effect. Chipped, not appropriate. As another antistatic measure, it is known to provide an antistatic layer using a cationic, anionic or nonionic surfactant on the back surface of the film substrate. However, a cosmetic material provided with an antistatic layer of an anionic or nonionic surfactant has a drawback that the antistatic effect is relatively inferior to that using a cationic surfactant. On the other hand, as the cationic surfactant, conventionally, ammonium sulfate,
Ammonium nitrate and ammonium chloride salts have been applied, but cosmetics provided with an antistatic layer composed of such a cationic surfactant can provide a good antistatic effect, but can be used during roll storage or in a mold. The surfactant is easily detached from the film substrate by the antistatic layer surface coming into contact with the mold when mounted inside, so that the antistatic effect is reduced, or the dropped surfactant is used. There is an inconvenience that the mold surface is corroded (rusted) with time and remains in the mold, and the mold surface needs to be periodically cleaned.

The present invention has been made in view of the above points, and has not only an excellent antistatic effect, but also a nonmetallic corrosive property that does not corrode an injection molding mold by separating from a film substrate. An object of the present invention is to provide a cosmetic material for simultaneous painting by injection molding, which is subjected to an antistatic treatment with a surfactant and is easy to handle.

[Means for solving the problem]

That is, the present invention provides: "A decorative layer is provided on a thermoplastic resin film substrate,
In the decorative material for simultaneous injection molding and painting in which at least the decorative layer is transferred and adhered to the surface of the injection molded product by performing injection molding after being mounted in the injection molding die, on the back surface of the thermoplastic resin film substrate, Dimethylethylammonium, trimethylammonium, which has good adhesion to the film substrate and has a property of not generating an acid by hydrolysis.
Injection molding characterized in that an antistatic layer comprising a cationic surfactant selected from the group consisting of methyl sulfate, ethyl sulfate and propyl sulfate of tetramethylammonium or dimethylpropylammonium is provided. "Cosmetic materials for simultaneous painting".

〔Example〕

 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows an embodiment of a decorative material 1 for simultaneous painting by injection molding according to the present invention. In the figure, reference numeral 2 denotes a thermoplastic resin film substrate, 3 denotes a decorative layer, and 4 denotes an antistatic layer.

As the thermoplastic resin film substrate 2, those applied to this kind of decorative material can be used in the same manner, and are appropriately selected and used according to the application. Specific examples of the material include polyethylene terephthalate, polybutylene terephthalate, polyethylene, polypropylene, polycarbonate, polyamide, polyethersulfone, polyamideimide, and the like. Terephthalate is preferred. The thickness of the film substrate 2 is 12 to 100 μm
It is about.

The decorative layer 3 is a known layer in this type of decorative material composed of a pattern, a character, a figure, and the like to be applied to the surface of the injection-molded product, and is not particularly limited. is there. The decorative layer 3 is formed by a known method such as a printing unit.

The antistatic layer 4 according to the present invention is made of a cationic surfactant having a good fixability to the thermoplastic resin film substrate 2 and a property of not generating an acid by hydrolysis. . This antistatic layer 4 is usually formed by applying the above-mentioned cationic surfactant on the back surface of the film substrate 2 (in other words, on the surface in contact with the injection molding die surface). An agent may be formed by directly kneading the agent into the resin material of the film substrate 2 so that the surfactant is present on the surface layer on the back surface of the substrate. Specific examples of the cationic surfactant used in the present invention include methyl sulfate such as dimethylethylammonium, trimethylammonium, tetramethylammonium, and dimethylpropylammonium, ethyl sulfate, and propyl sulfate. These cationic surfactants are appropriately selected and used in accordance with the material of the film substrate 2, and among them, a combination of a trimethylammonium metasulfate surfactant and a polyethylene terephthalate film substrate is preferable. When the surfactant is applied to form an antistatic layer, the surfactant can be applied to the back surface of the film substrate by a known application method such as a coating method or a spray method using a solvent or the like. In this case, the coating amount is preferably about 0.05 to 0.5 g / m ² . The surface resistance of the decorative material 1 of the present invention provided with the antistatic layer 4 as described above is 10 ⁷ to 10 ¹² Ω at 50% RH. Surface resistance value is 10 ¹²
If it exceeds Ω, a sufficient antistatic effect cannot be obtained.

The cosmetic material 1 of the present invention may have another layer formed as needed. For example, when the decorative material 1 is used as a transfer foil, as shown in FIG. 1, the base material 2 and the decorative layer 3 are used to facilitate peeling of the film base material 2 after injection molding.
A release treatment layer 5 can be provided between the two. In addition, layers such as a gloss adjusting layer, a release layer, and a vapor deposition layer may be appropriately provided.

In using the simultaneous decorating material 1 for injection molding of the present invention, the decorative material 1 is mounted such that the antistatic layer 4 side is in contact with the cavity surface of the mold for injection molding, and then the mold is closed. Injection molding is performed by injecting and filling a molten resin for injection molding into a mold, releasing the mold after completion of molding, and peeling and removing the film substrate 2. A molded article can be obtained. The peeling of the film substrate 2 is performed between the release processing layer 5 and the decorative layer 3,
At this time, the release treatment layer 5 also remains on the substrate 2 side and is removed. The supply system for mounting the decorative material 1 may be a continuous automatic supply of a long decorative material intermittently or a single-piece decorative material may be supplied for each molding.

In this embodiment, a decorative material used as a transfer foil type for peeling and removing a film substrate after injection molding has been exemplified. For example, as shown in FIG. It may be configured as a label type that is used by sticking it to the surface of an injection molded product together with 3 or the like. 6 in the figure
Indicates an adhesive layer.

Next, the present invention will be described in more detail with reference to specific examples.

Example 1 On a non-release layer side of a 38 μm-thick polyester film substrate (Diafoil GH38) having a release layer on one side, a 0.2% solution of isopropyl alcohol of dimethylsulfate trimethylammonium salt was dried to a coating thickness of 0.1%. The antistatic layer is provided by gravure coating to have a g / m ² . Next, a release layer (Co., Ltd.) was applied to the release layer surface by gravure printing.
Showa Ink Industries, Ltd .: Haklinis 46-7), a pattern layer (BCT black), and an adhesive layer (HS Rough Gray) were sequentially printed to form a transfer foil type decorative film material.

The obtained decorative film material is placed so that the antistatic layer side is in contact with the inner surface of the cavity of the injection molding machine mold, the AS resin is melted at 230 ° C, and injection molding is performed under the condition of cooling for 30 seconds. The film substrate was peeled off and painted. Such injection molding simultaneous painting was continuously performed 100 shots.

As a result, there is no adhesion of dust to the decorative film material, adhesion of antistatic agent to the mold, no film wrinkles during molding, etc.
Good transfer was obtained, and an injection molded product with a beautiful appearance was obtained.

Example 2 A decorative film material was prepared under the same conditions as in Example 1 except that diethylammonium ethylsulfate was used as the cationic surfactant, and thereafter, simultaneous painting was performed by injection molding. A high-quality molded product was obtained in the same manner as in Example 1.

Comparative Example 1 A decorative film material was prepared in the same manner as in Example 1 except that betaine, an amphoteric surfactant, was used as a surfactant, followed by simultaneous injection molding. As a result, no dust adhered to the film at all, but surfactant adhesion to the mold cavity and film wrinkling during molding were observed around 40 shots, making it difficult to obtain good molded products. Was.

Comparative Example 2 A decorative film material was prepared in the same manner as in Example 1 except that no surfactant was provided on the film base material, and thereafter, simultaneous painting was performed by injection molding. As a result, dust attached to the film substrate was remarkable, and when placed in the mold cavity, the dust adhered more than necessary, and dust marks were formed on the molded product.

The surface resistance value of each of the decorative film materials obtained in Examples 1 and 2 and Comparative Examples 1 and 2 was measured, and the adhesion of each surfactant to the film substrate was examined as follows. Furthermore, the degree of dust adhesion to the decorative film material and the occurrence of wrinkles during molding were examined, and the results are shown in the following table.

For the measurement of the sticking property of the surfactant, prepare a film test piece cut and cut to 25 mm x 180 mm by applying and coating each surfactant so that the surface resistance value becomes 1 to 3 x 10 ¹¹ Ω,
The surface of this test piece was washed with methanol and the circumference was 20 mm.
Abut the half of the peripheral surface (10mm) of the fixed mirror roll,
The test piece is reciprocated in the length direction of the film with a load of 100 g against the half circumference of the roll, and the surface resistance is measured with a surface resistance meter until the surface resistance reaches 10 ¹² Ω or more. The measurement was performed by counting the number of times. The adhesion of the surfactant was evaluated as ◎: 10 or more times ◎: 5 to 9 times ×: 0 to 4 times

Example 3 In the same manner as in Example 1 except that a urethane resin pressure-sensitive adhesive was printed and formed so as to have a dry coating thickness of 20 g / m ² instead of the adhesive layer provided next to the pattern layer in Example 1, A decorative film material was created. The obtained decorative film material was a good label-type decorative material with little adhesion of dust.

Example 4 A decorative film material was prepared in the same manner as in Example 1, except that a gloss adjusting layer composed of an aminoalkyd resin and silica was printed in a pattern between the release layer and the release layer. Thereafter, injection molding was performed. As a result, good injection molding was performed at the same time, and a molded article with a beautiful appearance having partially different gloss levels was obtained.

〔The invention's effect〕

As explained above, the decorative material for simultaneous injection molding and painting of the present invention has an antistatic layer formed on the back surface of a thermoplastic resin film substrate using a cationic surfactant having the above-mentioned properties. As a result, a sufficient and sufficient antistatic effect is obtained, so that there is no danger that dust in the atmosphere will be inadvertently adsorbed on the surface of the decorative material, and wrinkles do not occur and a good mold can be obtained. Mounting is possible. In addition, the cationic surfactant has excellent properties of fixing to the film substrate and also has the property of not generating an acid by hydrolysis,
When the cosmetic material is wound and stored, or when it is mounted in a mold, the surfactant is hardly detached, and even if the surfactant is detached and remains in the mold, the surfactant is not removed. Since it does not react with moisture in the atmosphere to generate an acid, there is no risk of corroding the mold surface.

Therefore, according to the present invention, a stable antistatic effect is maintained for a long time without the possibility that the surfactant is released and the antistatic effect is reduced, and the metal for injection molding is maintained due to the nonmetallic corrosion of the surfactant. The cumbersome maintenance of the mold is also eliminated, and as a result, a high-quality painted injection molded product free from molding defects can be stably obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the decorative material of the present invention, and FIG. 2 is a sectional view showing another embodiment of the decorative material of the present invention. DESCRIPTION OF SYMBOLS 1 ... Cosmetic material for simultaneous painting by injection molding 2 ... Thermoplastic resin film base material 3 ... Decorative layer 4 ... Antistatic layer

Continuation of front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B29C 45/00-45/84

Claims (1)

(57) [Claims] 1. An injection molding method in which a decorative layer is provided on a thermoplastic resin film substrate, mounted in an injection molding die, and then subjected to injection molding to transfer and attach at least the decorative layer to the surface of the injection molded product. In the decorative material for simultaneous molding and painting, dimethylethylammonium, trimethylammonium, and tetramethylammonium, which have good adhesion to the film substrate and do not generate a hydrolyzed acid, are formed on the back surface of the thermoplastic resin film substrate. Injection molding simultaneously provided with an antistatic layer comprising a cationic surfactant selected from methyl sulfate, methyl sulfate, ethyl sulfate, and propyl sulfate of methyl ammonium or dimethyl propyl ammonium A cosmetic material for painting.