JPH04113900A - Transfer sheet - Google Patents

Abstract

PURPOSE:To prevent the occurrence of a fault such as an adhesive peeling off an adhesive layer and sticking to a heating plate by providing the adhesive layer containing a matting agent on a side which comes in contact with a medium for transfer of a transfer layer formed on a peel-off base. CONSTITUTION:Silica powder, glass bead or calcium oxide is used as a matting agent contained in an adhesive layer 5. The recommended grain diameter of the matting agent is 1.0 to 6.0mum, especially 2.0 to 5.0mum. Further the recommended dosage of the matting agent is 1.0 to 10.0wt.%, especially 1.0 to 5.0wt.%. If the matting agent is added to the adhesive agent 5 of a transfer sheet, a fault such as an adhesive peeling off the adhesive layer 5 and sticking to a heating plate for preliminary formation can be prevented during the use of the transfer sheet 1 for in-mold transfer. Especially the mentioned effects are remarkable, if a resin having Tg of 55 to 95 is used as a resin making up the adhesive layer 5.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a transfer sheet, and particularly to a transfer sheet suitable for simultaneous transfer in injection molding (so-called in-mold transfer).

[Conventional technology]

Transfer sheets, in which a transfer layer consisting of a pattern or the like is formed on a releasable base material, are widely used for purposes such as adding patterns to the surfaces of various products.

As a method of transferring onto the surface of the transferred item using this type of transfer sheet, the transfer sheet is superimposed on the surface of the transferred item,
The so-called hot stamping method, in which the transfer layer is transferred to the surface of the object to be transferred by applying heat and pressure from the base material of the transfer sheet, has been widely used in the past, but in recent years, it has been widely used to transfer the transfer sheet into an injection mold. Simultaneous injection molding transfer (hereinafter referred to as in-mold transfer), in which transfer and molding are performed simultaneously by injection molding, is also widely practiced. In this in-mold transfer, the transfer layer side of the transfer sheet faces the inner surface of the mold and is heated from the transfer layer side using a hot plate, and the transfer sheet is molded to follow the shape inside the mold, making the transfer sheet adhere to the inner surface of the mold. After the mold is clamped, molten resin is injected into the mold to integrate the transfer sheet and the injected resin.
Next, the molded product is cooled and taken out from the mold, and then the base material is peeled off to obtain a product to which the transfer layer has been transferred.

[Problems to be Solved by the Invention] This type of transfer sheet is usually provided with an adhesive layer on the side of the transfer layer that comes into contact with the transferred item in order to improve the adhesion to the transferred item. However, when using conventional transfer sorting in which an adhesive layer is provided on the side of the transfer layer that contacts the transferred product, when used for in-mold transfer, thermojet is used for preforming to bring the transfer sheet into close contact with the inner surface of the mold. The adhesive tends to peel off and stick to the transfer sorting adhesive layer on the heating device of the equipment, resulting in a decrease in the adhesion of the transfer layer to the transferred product and poor adhesion between the transfer layer and the molded product. There were other problems, such as the adhesive adhering to the heating device reducing the heating efficiency and requiring a complicated work to remove the adhering adhesive from the heating device.

The present invention has been made in view of the above points, and it is an object of the present invention to provide a transfer sheet that solves the drawbacks of the above-mentioned prior art.

[Failure to solve the problem]

The transfer sort of the present invention is characterized in that an adhesive layer containing a matting agent is provided on the side of the transfer layer provided on the releasable base material that contacts the transfer target. The matting agent contained in the adhesive layer in the transfer sorting of the present invention has a particle size of 1.0 to 6.
On is preferable, and the content is 1.0 to 10.0
Preferably, it is % by weight. Further, in the transfer sheet of the present invention, it is preferable that the resin constituting the adhesive layer has a Tg of 55 to 95.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on the drawings.

The first part shows an example of the transfer sheet 1 of the present invention, in which a transfer layer 6 consisting of a release layer 3, a decorative layer 4, and an adhesive layer 5 is formed on a release base material 2. Become.

A moldable film or sheet is used as the base material 2, and examples of this material include polyvinyl chloride, polyvinylidene chloride, vinyl acetate-vinyl chloride copolymer, polyvinyl fluoride, polyvinyl butyral, polyvinylidene fluoride, etc. Vinyl polymers, styrene resins such as polystyrene, acrylic styrene, and ABS, acrylic resins such as polyethyl methacrylate, polymethyl methacrylate, and polyacrylonitrile, and polyolefins such as polyethylene, polypropylene, and polymethylpentene MMB
, cellulose derivatives such as cellulose acetate and nitrocellulose, polyamide resins such as nylon-6 and nylon-6,6, polyester resins and polyester elastomers such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene terephthalate-isophthalate copolymers, Examples include rubber resins such as butadiene rubber, chloroprene rubber, and silicone rubber, polyvinyl alcohol resins such as vinylon and polyvinyl alcohol, urethane resins, and polycarpore F. The base material 2 may be a laminate of two or more films or sheets made of different materials. The thickness of the base material 2 is usually about 5 to 200 nm, preferably 12 to 50 nm.

The transfer layer 6 is provided on the surface of the base material 2 on the side where the transfer layer 6 is provided.
For the purpose of improving the releasability of the mold, a release layer 7 can be provided as necessary. The release layer 7 is made of wax, fatty acid amide, silicone, thermosetting resin, ionizing radiation curable resin, etc., as is used in ordinary transfer sheets.

When the mold release layer 7 is provided, in order to improve the adhesion of the mold release layer 70 to the base material 2, the surface of the base material 2 is usually treated with an easy-to-adhesive treatment such as a corona discharge treatment or an unsaturated polyester resin paint coating treatment. Sexual treatment is performed.

The peeling layer 3 facilitates the peeling of the transfer layer 6 from the base material 2, and functions as a protective layer for the decorative layer 4 in the transfer layer 6 after the transfer. The release layer 3 is formed by applying a resin such as acrylic resin, vinyl chloride-vinyl acetate copolymer, polyurethane, or epoxy resin by a coating method such as gravure coating or roll coating, or a printing method such as screen printing or gravure printing. can be formed.

The thickness of the peeling layer 3 is usually about 5 to LOn.

The decorative layer 4 is a layer for imparting design to the surface of the transferred product, and examples of the decorative layer 4 include a pattern layer, a colored layer, a metal thin film layer, and a combination thereof.

The pattern layer and colored layer are printed as desired by gravure printing, silk screen printing, offset printing, etc. using ordinary gravure printing inks such as acrylic, vinyl chloride-vinyl acetate copolymer, aminoalkyne F, and cellulose inks. It can be formed by printing in a pattern, or by printing or coating the entire surface. Further, the metal thin film layer can be formed by vacuum evaporation, sputtering, etc. of metals such as aluminum, chromium, and nickel. Alternatively, it may be formed by laminating metal foils. The metal thin film layer is not limited to the entire surface, but may be formed partially in a desired pattern.

When forming a metal thin film layer by vacuum deposition or sputtering, it is particularly preferable to provide an anchor layer first and then form it on the anchor layer. The thickness of the decorative layer 4 is usually about 3 to 10 nm in the case of a pattern layer or a colored layer, and 100 to 10 nm in the case of a metal thin film layer made by rattan or sputtering.
Approximately 000 people.

The adhesive layer 5 is made of acrylic, styrene, or vinyl chloride.
A vinyl acetate copolymer resin, a chlorinated polypropylene resin, or a mixed resin thereof may be used. Among these, one is selected and used depending on the material of the object to be transferred.

For example, if the material to be transferred is polystyrene resin, use acrylic, styrene, or a mixture thereof; if the material to be transferred is ABS or AS resin, use acrylic, vinyl chloride-acetic acid. It is preferable to use a material made of a vinyl copolymer system or a mixture thereof, and a material made of chlorinated polypropylene when the transferred article is made of a polypropylene resin. Adhesive layer 5
The thickness is usually about 2.0 to 20 mm.

As the matting agent contained in the adhesive layer 5, silica powder, glass beads, calcium oxide, etc. are used. These matting agents preferably have a particle size of 1.0 to 6°, particularly 2.0 to 5.0°. It is preferable to turn it on. The amount of the matting agent added is 1.0 to 1000% by weight, especially 1.0 to 5% by weight.
．． 0% by weight is preferred.

As described above, the transfer sheet 1 of the present invention contains a matting agent in the adhesive layer 5, so that when used for in-mold transfer, the adhesive peels off from the adhesive layer 5 and is attached to a heating device for preforming. This effect is particularly noticeable when a resin having a Tg of 55 to 95 is used as the resin constituting the adhesive layer 5.

When using the transfer sheet 1 of the present invention in an in-mold transfer method, first, as shown in FIG. The transfer sheet 1 is heated by a heater 10 from the adhesive layer 5 side of the transfer sheet 1, and the transfer sheet 1 is suctioned from the suction port 11 of the mold 8a to transfer the transfer sheet 1 to the mold 8a. Bring it into close contact with the cavity surface 9. After that, as shown in FIG. 2, the mold is clamped and the molten resin is injected into the molding chamber 13 from the injection port 12 provided in the other mold 8b.
Eject inside. After cooling and opening the mold and taking out the molded product 14 from the molding chamber 13, the base material 2 is peeled off and removed as shown in FIG. 3 (the mold release layer 7 is peeled off together with the base material 2). As a result, a molded article 14 having the transfer layer 6 of the transfer sheet 1 transferred thereon can be obtained.

The present invention will be explained in more detail by giving specific examples below.

Examples 1 to 3 Base sheet whose surface was subjected to mold release treatment with acrylic-melamine resin (manufactured by Diafoil: G900C1 thickness 50
On the release-treated surface of n), apply an acrylic release layer forming ink (manufactured by Showa Ink Kogyosho 2 - Kuri 46-7) using a gravure coating method so that the dry coating amount is 2.0 g/rrf. A release layer is formed by applying a pattern layer-forming ink (manufactured by Showa Ink Industries) made of a mixture of vinyl chloride-vinyl acetate copolymer and acrylic resin on top of this release layer.
A wood grain pattern is gravure printed using the same method, and the composition for forming an adhesive layer shown in Table 1 is coated on the wood grain pattern using a gravure coating method to a thickness of 4.5 mm. A transfer sheet was prepared by forming an adhesive layer. Heat this transfer sheet at a temperature of 150°C.
The molded product was pre-molded with a polystyrene resin (Nippon Polystyrene Kogyo Co., Ltd.: S-Bly H () (501)) at 230°C and then molded from the mold. After taking it out, the base sheet was peeled off to obtain a molded product with a transfer layer transferred onto the surface.The adhesion of the transfer layer to the molded product, and whether or not the adhesive adhered to the heating device during preforming. are shown in Table 1.

Comparative Examples 1-2 Transfer was performed under the same conditions using transfer foils obtained in the same manner as in Examples 1-3, except that the adhesive layer was formed with an adhesive not containing the matting agent shown in Table 1. . Table 1 also shows the adhesion of the transfer layer to the molded product and the presence or absence of adhesion of adhesive to the heating device during preforming.

Example 4 A transfer sheet obtained in the same manner as Examples 1 to 3 except that the adhesive layer was formed using the composition for forming an adhesive layer shown in Table 2 was preformed and molded in a 150°C heater. ABS resin (body skin Naugatuck: KU-600) was injection molded at 240° C. in close contact with the cavity surface of the mold. After cooling and taking out the molded article from the mold, the base material sort was peeled off to obtain a molded article on which a transfer layer was transferred and formed on the surface. Table 2 also shows the adhesion of the transfer layer to the molded product and whether or not the adhesive adhered to the heating device during preforming.

Comparative Examples 3 to 4 Transfer was performed under the same conditions using a transfer foil obtained in the same manner as in Example 4, except that the adhesive layer was formed using an adhesive not containing a matting agent shown in Table 2.

Table 2 also shows the adhesion of the transfer layer to the molded product and the presence or absence of adhesive adhesion to the heating device during preforming.

〔Effect of the invention〕

Since the transfer notebook of the present invention contains a bulky matting agent in the adhesive layer, there is no possibility that the adhesive layer may peel off from the adhesive layer and adhere to the heating device during preliminary bottom forming when used for in-mold transfer. Therefore, it is possible to obtain a molded product with excellent adhesion between the transfer layer and the transferred product without requiring the trouble of removing the adhesive adhered to the heating device unlike when using a conventional transfer sheet. I can do it.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, and FIG. 1 is a longitudinal cross-sectional view of one embodiment of the transfer sheet of the present invention, and FIGS. 2(a) and (b) show the transfer sheet of the present invention used for in-mold transfer. FIG. 3 is a schematic cross-sectional view showing one step when performing transfer, and FIG. 3 is a cross-sectional view of essential parts showing a state in which the base material is peeled off after the molded product is taken out from the mold. 1...Transfer sheet 2...Base material 5...Adhesive layer 6...Transfer layer/transfer/G/Transfer layer Fig.

Claims (4)

[Claims] (1) A transfer sheet, characterized in that an adhesive layer containing a matting agent is provided on the side of the transfer layer provided on a removable base material that contacts the transfer target. (2) The particle size of the matting agent contained in the adhesive layer is 1.0
The transfer sheet according to claim 1, wherein the transfer sheet has a thickness of 6.0 μm. (3) 1.0 to 10.0% by weight of matting agent in the adhesive layer
The transfer sheet according to claim 1 or 2, characterized in that the transfer sheet contains: (4) The transfer sheet according to any one of claims 1 to 3, wherein the resin constituting the adhesive layer has a Tg of 55 to 95.