KR100259201B1 - Stamping foil - Google Patents

Abstract

In the stamping foil comprising a biaxially stretched polyester base film and a release layer, a coloring layer, a metal deposition layer, and an adhesive layer sequentially formed on one surface of the base film, the adhesive layer is 100 parts by weight of acrylic resin, 100 to 200 parts by weight The stamping foil according to the present invention, which is an adhesive layer comprising a vinyl resin and 200 to 250 parts by weight of nitrocellulose, has excellent adhesiveness, blocking resistance, cutting property and degassing property, and is particularly suitable for the adherend of the polyethylene resin component. Suitable for transferring graphic patterns, etc.

Description

Stamping foil {STAMPING FOIL}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stamping foil, and more particularly, to a stamping foil including an adhesive layer having excellent adhesion to an adherend and excellent blocking resistance, cutting property, and degassing property. ).

Stamping foil is used to form graphic patterns and texts of metal components on adherends of various materials such as plastic molded products, leather products, wood products, and paper products. In some cases, hot stamp tape Also called tape or thermal transfer tape. Stamping foil is a structure in which a release layer, a coloring layer, a metal deposition layer, and an adhesive layer are sequentially laminated on a base film made of a polyester resin, and is a hot stamping process that is one of dry printing methods. Used.

The hot stamping process refers to a heat stamping process of attaching a desired graphic pattern or letter by placing a stamping foil at a deposition position on a plastic molded product and pressing the stamping foil with a preheated mold. In more detail, by pressing the stamping foil with a heated platen, only a specific portion of the adhesive layer of the stamping foil is pressed onto the target material so that only the adhesive layer of the heat-transferred specific portion adheres to the target material, followed by removing the base film. Desired graphic patterns and the like can be formed in plastic molded products and the like. In some cases, instead of pressing the stamping foil using a heated platen, a step of pressing the stamping foil with the platen and then heating only a specific portion may be adopted.

The present invention particularly relates to improving the physical properties of the adhesive layer among the layers constituting the stamping foil. The adhesive layer of the stamping foil has a different resin composition depending on the target material to be adhered, that is, the adherend, and typically, a resin having excellent adhesion to the adherend is used. Particularly important among preferable conditions that the adhesive layer of the stamping foil should have include the following.

First, the adhesion to the adherend should be excellent. Usually, in the case of polyolefin adherends such as polyethylene and polypropylene, it is known that adhesion is particularly difficult.

Second, the blocking phenomenon should not occur. In the manufacturing process of the stamping foil, as in the case of a conventional film is subjected to the winding (winding) to a dried film, a phenomenon that the film sticking to each other, so-called blocking phenomenon is likely to occur.

Third, there is a cutting property (cutting property). Typically, the adhesive has a high elongation and is poor in cutability. Cutting is an important factor directly related to the economics of the actual stamping foil manufacturing.

Finally, good degassing properties are required. The transfer process using a stamping foil involves an up-down stamping method in which a stamped foil placed on a substrate is heated by means of a heated platen, in which air between the substrate and the stamping foil cannot escape. If you are trapped. In such a case, after the transfer, the non-transferred portion is formed on the surface of the adherend where the residual air is located, so that the portion appears in the form of a dot. This phenomenon occurs particularly frequently during transfer to a wide surface. In order to solve this problem, it is desirable that the adhesive layer has a degassing property that allows air to escape well during adhesion with the adherend.

In order to manufacture an adhesive layer that satisfies the above conditions, many researches and developments have been made in the past. According to a typical example of the prior art, an acrylic resin, a vinyl resin, and an inorganic filler are mixed and used as the adhesive layer. In particular, in the case where the polypropylene-based adherend is the object, a polypropylene-based adhesive resin is added to the mixture. Herein, chlorinated polypropylene is mainly used as the polypropylene resin.

However, according to the prior art, some of adhesiveness, blocking resistance, cutting property, or degassing property can be satisfied, but the above requirements cannot be evenly met. For example, in the case of a biaxially oriented polypropylene-based adherend, the surface of the biaxially oriented polypropylene-based adherend is very smooth. Therefore, when using a stamping foil according to the prior art, the degassing property was considerably difficult.

Therefore, there is a growing interest in stamping foils having an adhesive layer that is sufficiently satisfied with adhesion, blocking resistance, cutting properties, and degassing properties by adjusting the type and composition of the resin and filler used.

The technical problem to be achieved by the present invention is to provide a stamping foil comprising an adhesive layer excellent in adhesion, blocking resistance, cutting and degassing properties.

In order to achieve the above technical problem, in the present invention, in the stamping foil comprising a biaxially stretched polyester base film and a release layer, a coloring layer, a metal deposition layer and an adhesive layer sequentially formed on one surface of the base film, the adhesive layer is A stamping foil is provided, which is an adhesive layer comprising 100 parts by weight of acrylic resin, 100 to 200 parts by weight of vinyl resin, and 200 to 250 parts by weight of nitrocellulose.

Hereinafter, the present invention will be described in detail.

The present invention relates to a stamping foil comprising an adhesive layer that can be used in general adherends including polyester resins, but is particularly useful for polyethylene-based adherends.

Acrylic resins are relatively good in adhesion, blocking resistance and cutting properties. In the present invention, it is preferable to use a thermoplastic methylacrylic resin having a molecular weight of 20.000 to 30,000 and a glass transition temperature of 62 ° C.

As the vinyl resin, it is preferable to use a vinyl chloride / vinylacetate copolymer having a molecular weight of 27,000 and a glass transition temperature of 74 ° C. Both acrylic resins and vinyl resins improve the adhesion of the adhesive layer as the content increases, while the composition ratio is important because other physical properties have the disadvantage of deteriorating accordingly.

Nitrocellulose is especially used when the polyethylene-based adherend is an object as described above.

The composition ratio of the three resins is preferably 100 to 200 parts by weight of vinyl resin and 200 to 250 parts by weight of nitrocellulose based on 100 parts by weight of acrylic resin.

It is preferable that a filler is added to the composition in order to increase cutting resistance, blocking resistance, in particular degassing resistance. When the filler is added, protrusions are formed on the surface of the adhesive layer to increase slipperiness, thereby improving blocking resistance in the winding process as well as improving degassing properties. The filler to be added is not particularly limited as long as it is conventionally used, but it is preferable to use silica having a particle diameter of 0.1 to 2 microns. The addition amount is suitably 35 to 50 parts by weight based on 100 parts by weight of the mixture of the acrylic resin, the vinyl resin, and nitrocellulose. When the amount of the filler added is less than the above range, the effect of improving the blocking resistance and the degassing resistance is insignificant. On the other hand, when the amount of the filler exceeds the above range, the adhesiveness decreases. Or deaeration may be caused.

Hereinafter, a method of manufacturing a stamping foil according to the present invention will be described. Except for the adhesive layer, the method is typically used for the production of stamping foil, which will be described schematically.

The stamping foil according to the present invention uses a polyester film as the base film. A polyester film is obtained by the polycondensation reaction of dibasic acid and dihydric alcohol.

As the dibasic acid component, aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, naphthalene dicarboxylic acid, diphenoxyethane dicarboxylic acid, diphenyl dicarboxylic acid, diphenyl ether dicarboxylic acid, and the like are preferable. Preferred is terephthalic acid.

As a dihydric alcohol component, ethylene glycol, propanediol, butanediol, pentanediol, hexanediol, neopentylglycol, etc. are preferable, and ethylene glycol is more preferable.

The release layer is formed by coating the composition for the release layer on one surface on a base film according to a conventional method and then drying. As the composition for the release layer, waxes of high melting point, higher fatty acids and salts thereof, esters, silicone oils, alkyl fluoride compounds, polyvinyl alcohol, low molecular weight polyethylene, and the like may be used.

The colored layer is formed by coating the composition for the colored layer on the release layer and then curing through a drying process. Examples of the composition for the colored layer include isocyanate, nitrocellulose and diallyl phthalate and pigments.

A stamping foil is prepared by forming a colored layer, then depositing a metal such as aluminum on the colored layer to form a metal layer, and finally coating an adhesive layer composition on the metal layer.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. However, the scope of the present invention is not limited thereto. Evaluation of the physical properties of the stamping foil prepared in the following Examples and Comparative Examples was carried out through the evaluation of the following items.

<Adhesiveness>

After attaching the cellophane tape on the transferred surface of the adherend and detaching the cellophane tape, the adhesiveness was evaluated by observing the damage of the transferred surface.

<Blocking resistance>

When unwinding the stamping foil product wound in a roll state, it was evaluated by visually observing whether the contact surface of the film was smoothly released.

<Cutting property>

The evaluation was divided into 10 grades, from the 1st grade where the smallest printing was possible, to the extent that the writing was not possible (used to transfer to the front).

<Degassing>

Degassing was evaluated by measuring how many points occurred due to non-transferring on the surface of the adherend after transferring using a metal plate with a width of 3 cm and a pattern without a pattern.

<Example>

A gravure roller was used to apply a composition for forming a release layer containing 15% of ester wax to a polyethylene terephthalate film having a thickness of 12 μm, and then dried to form a release layer having a thickness of 0.05 μm.

Next, a polyurethane resin (PL-50, manufactured by Construction Chemicals) and a dye (Blue GL, manufactured by Ciba-Geigy) (weight ratio: 95: 5) were dissolved in methyl ethyl ketone / toluene (2: 1) to obtain a resin concentration. 20% solution was prepared. The resulting solution was applied onto the release layer, dried and cured at 180 ° C. for 15 seconds to form a colored layer having a thickness of 1.0 μm.

Aluminum was vacuum deposited on the colored layer to form a metal deposition layer having a thickness of 0.02 μm. Finally, after preparing a composition for an adhesive layer having a composition as described below, it was applied to the metal layer to form a stamping foil by forming an adhesive layer having a thickness of 1㎛.

1.4% by weight of acrylic resin (A-111-50, manufactured by DIC Corporation)

Vinyl resin (VMCH, Union Carbide) 2.2 wt%

Nitrocellulose 3.4% by weight

Filler (Aerosil 200, manufactured by Deggusa) 3.0 wt%

Toluene 20% by weight

Methyl ethyl ketone 50 wt%

20% by weight of ethyl acetate

The stamping foil prepared as described above was transferred to the adherend with an up-down stamping machine. Paper materials include paper, ABS resin and PVC resin. PS resin and polyethylene resin were selected. As a result of measuring the adhesiveness, blocking resistance, cutting property, and deaeration property with respect to the transferred adherend as described above, the overall result was satisfactory. In particular, unlike the conventional adhesion to the polyethylene resin, as a result of using the adhesive layer according to the present invention, it was confirmed that the adhesion significantly improved compared to the conventional stamping foil.

As can be seen from the above, the stamping foil according to the present invention is excellent in adhesiveness, blocking resistance, cutting property and degassing property and the like, and exhibits good adhesion even to a polyethylene adherend which is particularly difficult to adhere.

Claims (4)

(a) biaxially stretched polyester base film and (b) In the stamping foil comprising a release layer, a coloring layer, a metal deposition layer and an adhesive layer sequentially formed on one surface of the base film, The adhesive layer includes 100 parts by weight of acrylic resin, 100 to 200 parts by weight of vinyl resin, and 200 to 250 parts by weight of nitrocellulose, and has a particle diameter of 0.1 to 2 microns and a content of the acrylic resin, vinyl resin, and nitrocellulose. Stamping foil, characterized in that it further comprises a filler (filler) of 35 to 50 parts by weight based on 100 parts by weight of the mixture. The stamping foil of claim 1, wherein the filler is silica. The stamping foil according to claim 1 or 2, wherein the acrylic resin is a thermoplastic methylacrylic resin having a molecular weight of 20,000 to 30,000 and a glass transition temperature of 62 ° C. The stamping foil of claim 1 or 2, wherein the vinyl resin is a vinyl chloride / vinylacetate copolymer having a molecular weight of 27,000 and a glass transition temperature of 74 ° C.