JPS6358118B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a multicolor printing method on a curved body, and its purpose is to print on the surface of an article having a curved body made of not only heat-resistant but also non-heat-resistant materials. It is an object of the present invention to provide a multicolor printing method on a curved body, which can easily print multicolor gradation patterns using an economical process.

BACKGROUND ART Conventionally, printing methods using pads are suitable for printing on the surface of objects even if they are somewhat distorted, and have therefore been widely used as a method of printing on surfaces of objects exhibiting curved surfaces. However, this so-called octopus printing method is mainly designed to print single-color designs, and when printing multicolor designs, it is necessary to press the pad multiple times, and the pad is made of an elastic material. Therefore, it was impossible to accurately register and position the design, and it was impossible to create a detailed multicolor gradation design.

Therefore, a tacho printing method using a transfer sheet has been devised as a method for printing multicolor gradation patterns on articles exhibiting various curved surfaces. That is, a method of printing a multicolor gradation pattern by bringing the pattern of the transfer sheet into close contact with an article exhibiting a curved surface using a vacuum forming means and a pressure forming means using a pad while heating and softening the transfer sheet (Japanese Patent Laid-Open No. 159006-1986) (see publication). The octopus printing method using this transfer sheet has features such as being able to easily and accurately print multicolor gradation patterns on objects exhibiting a curved surface, and also having good productivity. However, in order to transfer the design on the transfer sheet to the surface of the article, a step of heating and softening the transfer sheet is required, and as a result, printing cannot be performed without using a heat source. Therefore, thermal energy was required, and careful temperature control was also required. Furthermore, because of the process of transferring the design of the transfer sheet to the surface of the article using heat, the object to be transferred has to be limited to articles having heat resistance.

As a result of various research experiments to solve each of the above-mentioned problems, the inventors of the present invention have found that it is possible to easily create multicolor gradation patterns on curved objects with a single press of a pad without using thermal energy. They also completed a method that allows for accurate printing. That is, in the present invention, after peeling off the base sheet from a transfer sheet in which a transfer layer consisting of an elastomer film and a water-soluble and adhesive pattern layer is laminated on a non-stretchable base sheet, After humidifying the layer, the pattern layer is placed in contact with the surface of the object to be transferred, and then a transfer pad is pressed from the elastomer film side of the transfer layer to bring the object to be transferred and the transfer layer into close contact. , a multicolor printing method on a curved object, characterized in that a pattern is printed on the surface of the object to be transferred.

The present invention will be explained in more detail below based on the drawings.

First, the structure of the transfer sheet 5 used in the present invention will be explained (see FIG. 1).As the base sheet 1 of the transfer sheet 5 used in the present invention, a film that does not expand or contract due to heat, tension, etc. is used. When printing a pattern on the elastomer film 2, the base sheet 1 prevents misregistration and misalignment of the pattern that occurs due to the expansion and contraction of the elastomer film 2, allowing delicate and accurate multicolor printing. This is to enable a gradation pattern to be obtained. Examples of materials having this property include polyethylene terephthalate, polypropylene, vinyl chloride, plastic films such as nylon, release paper, papers such as glassine paper, and cellophane.

Next, as the elastomer film 2, there is used a film that is peelable from the base sheet 1, has ductility, is suitable for multicolor printing, and has excellent ink releasability. This elastomer film 2 must be able to stretch and adhere tightly to the surface of the article without breaking when pressed by the transfer pad. Examples of resins having these properties include polyurethane resins, polyester resins, and styrene-butadiene block copolymer resins. These resins are formed on the entire surface of the base sheet 1 by an extrusion method, a roll coating method, a reverse coating method, a bar coating method, or the like.

Further, a water-soluble and adhesive pattern layer 3 is formed on the elastomer film 2. To form the pattern layer 3, an ink composition is used which is prepared by sufficiently mixing and kneading a coloring agent such as a dye or pigment, a binder, etc. together with a dispersant using a solvent or the like. As the binder, various resins that are water-soluble and have adhesive properties are used. Examples include acrylic resin, vinyl acetate resin, and the like.

Further, when the binder has elastomer properties, it is more desirable because it does not stretch like the elastomer film 2 and cause cracks in the pattern when pressed by the transfer pad. As the coloring agent, various dyes and pigments can be selected and used depending on the type of the article to be transferred.

Using the ink composition, arbitrary characters and patterns are formed by a conventional printing method such as a gravure method, an offset method, or a screen method.

The transfer sheet 5 used in the present invention having the above-mentioned structure has the pattern layer 3 which is water-soluble and has adhesive properties, and a layer (printing layer 6) for forming characters, figures, etc., which is water-soluble and has adhesive properties. (water-soluble adhesive layer 7) and may be provided separately (see FIG. 2). That is, a transfer sheet 5' consisting of an elastomer film 2, a printing layer 6, and a water-soluble adhesive layer 7 can also be used on the base sheet 1. In this case, the printing layer 6 may be water-soluble or oil-soluble, and does not need to have adhesiveness to the transfer target. The printing layer 6 can be formed by the same printing method as in the case of forming the pattern layer 3 on the elastomer film 2. After the printing layer 6 is formed, it is formed on the entire surface using a water-soluble adhesive by a normal printing coating method, such as a bar coating method, a roll coating method, a reverse coating method, a gravure coating method, or the like.

If the printing layer 6 and the water-soluble adhesive layer 7 are made of a resin having elastomer properties like the pattern layer 3, they will stretch like the elastomer film when pressed by the transfer pad, causing cracks in the pattern, etc. It is desirable that it does not occur.

Next, a method of performing multicolor printing using the transfers 5 and 5' having the above structure will be explained.

First, the base sheet 1 is peeled off from the transfer sheets 5, 5'. Peeling of the base sheet 1 may be carried out during or after humidification of the transfer layers 4, 4', but it is preferably carried out before humidification because the transfer process must be carried out quickly while the water-soluble adhesive is in an activated state. .

Immediately before transfer, a solvent is used to moisturize the water-soluble adhesive in order to activate it. Here, the solvent is used to swell the adhesive to a certain extent and make it adhesive, and since the adhesive used in the present invention is water-soluble, water, alcohol, etc. can be used. As a method for humidifying, a solvent is printed and coated on the pattern layer 3 or water-soluble adhesive layer 7 side of the transfer sheets 5, 5' by a gravure coating method, an offset method, a roll coating method, a bar coating method, a spray method, or the like. To do this. The amount of solvent used during humidification is adjusted to be sufficient to activate the adhesive. Further, care must be taken so that the solvent does not have an adverse effect on the object to be transferred.

The transfer layers 4, 4' moistened by the above method are
The pattern layer 3 side or the water-soluble adhesive layer 7 side of the transfer layers 4, 4' can be made to lie along the surface of the article to be transferred to a certain extent. At this stage, the transfer layers 4, 4'
is placed on the surface of an article exhibiting a curved surface, and is not in close contact. Thereafter, it is pressed with a transfer pad to completely adhere to the surface of the article and transfer the design. Therefore, it is desirable that the transfer pad matches the shape of the object to be transferred. The material of the pad may be the same as that used in normal tacho printing, for example, an elastic material such as silicone rubber.

When the pattern transfer is completed as described above, a multicolored pattern is formed on the surface of the article.

Since the present invention is a multicolor printing method having the above configuration, the following effects can be obtained.

First, since transfer printing is performed using an elastic transfer pad and a transfer sheet with a multicolor gradation pattern printed on it, it is possible to easily and accurately print a multicolor gradation pattern on a curved object. can be printed on.

Further, since the transfer printing is performed by humidifying the transfer sheet and pressing it once with a transfer pad, productivity is excellent.

Another feature of the present invention is that the elastomer film of the transfer sheet used has elasticity, so even when applied to the uneven surface of an article, no sagging or the like will occur on the printed surface. Furthermore, since no heating process is required to transfer the design, it can be applied not only to heat-resistant materials but also to articles made of non-heat-resistant materials, and at the same time is suitable for the energy-saving era.

Examples of the present invention will be described below.

Example 1 A thermoplastic polyurethane elastomer was continuously coated on a non-stretchable silicone release paper using a hot melt extrusion method to form an elastomer film with a thickness of 15 μm, and further on the elastomer film was coated with the following composition: A multicolor gradation pattern was formed using printing ink using a gravure printing method to obtain a transfer sheet.

Polyvinyl alcohol (Gohsenol KL-
05.0619 Nippon Gosei Kagaku Kogyo) 20 parts Solvent (water + methanol) 100 parts Cationic dye 1 part (parts by weight) Next, peel off the silicone release paper from the above transfer sheet, spray water on the pattern layer, and remove the pattern layer. After being softened and activated, it was placed on top of an anodized aluminum container so that the surface of the pattern layer was in contact with it. Thereafter, a transfer pad made of silicone rubber was pressed from the elastomer film side to transfer the design. When the elastomer film was then peeled off, a delicate multicolor gradation pattern was obtained on the surface of the aluminum container.

Example 2 An elastomer film was formed on a non-stretchable polyethylene terephthalate film in the same manner as in Example 1, and a multicolor gradation pattern was formed thereon by gravure printing using a printing ink having the composition below. A transfer sheet was obtained.

Acrylic resin (Vanaresin MP85ουN・
350 Shin Nakamura Chemical) 10 parts Solvent (methanol) 10 parts Inorganic pigment for ceramics 20 parts Next, the polyethylene terephthalate film was peeled off from the above transfer sheet, and the pattern layer was softened and activated in the same manner as in Example 1, and then the ceramic The pattern layer was installed so as to be in contact with the unglazed surface. After that, it was pressed with a transfer pad in the same manner as in Example 1 to form an elastomer film (thermoplastic polyurethane resin).
When peeled off, a delicate multicolored gradation pattern was obtained on the unglazed ceramic surface.

Example 3 A polyester elastomer was continuously coated on a non-stretchable polypropylene film by a hot melt extrusion method to form an elastomer film with a thickness of 15 μm, and a printing ink having the following composition was further applied on the elastomer film. A printed layer with a multicolor gradation pattern was formed using the gravure printing method.

Acrylic resin (Teisan Resin 500D Teikoku Kagaku Sangyo) 10 parts Solvent (methanol) 20 parts Cationic dye 0.2 parts Then, a water-soluble adhesive layer is formed on the entire surface by gravure coating using a transparent adhesive having the composition below and transferred. Got a sheet.

Acrylic resin (Panaresin 604A Shin Nakamura Chemical) 10 parts Solvent (methanol) 2 parts Next, the polypropylene film was peeled off from the transfer sheet, the water-soluble adhesive layer was moistened with water by gravure coating, and the water-soluble After the water-soluble adhesive layer was softened and activated, it was placed on an alumite container so that it was in contact with the water-soluble adhesive. Thereafter, the pattern was transferred by pressing from the elastomer film side with a transfer pad. When the elastomer film was then peeled off, a delicate multicolor gradation pattern was obtained on the surface of the alumite container.

Example 4 An elastomer film was formed on a non-stretchable vinyl chloride film in the same manner as in Example 3, and a printed layer with a multicolor gradation pattern was printed thereon using a gravure printing method using a printing ink having the composition below. Formed.

Acrylic resin (Acrysize N2 Teikoku Kagaku Sangyo) 20 parts Solvent (methanol) 10 parts Inorganic pigment for ceramics 20 parts Surfactant 0.2 parts Then, roll coat the entire surface with a water-soluble adhesive with the following composition. An adhesive layer was formed to obtain a transfer sheet.

Modified vinyl acetate (PK-40 Nippon Gosei Kagaku Kogyo) 10 parts Solvent (methanol) 10 parts Next, the vinyl chloride film was peeled off from the transfer sheet, and the water-soluble adhesive layer was moistened with water by the offset method. After the water-soluble adhesive layer was softened and activated, it was installed so that it was in contact with the unglazed surface of ceramics. Thereafter, the pattern was transferred by pressing from the elastomer film side with a transfer pad. When the elastomer film was then peeled off, a delicate multicolored gradation pattern was obtained on the unglazed ceramic surface.

Example 5 A styrene-butadiene block copolymer resin was continuously coated on a non-stretchable nylon film by a hot melt extrusion method to increase the thickness.
An elastomer film with a thickness of 15 μm was formed, and a printed layer with a multicolor gradation pattern was further formed on the elastomer film by gravure printing using a printing ink having the composition shown below.

Acrylic resin (Coponil NS-20 Nippon Gosei Kagaku Kogyo) 10 parts Solvent (Troll) 5 parts Inorganic pigment for ceramics 20 parts Surfactant 0.2 parts After that, the entire surface was coated by roll coating using a transparent adhesive with the following composition. A water-soluble adhesive layer was formed on the film to obtain a transfer sheet.

Modified vinyl acetate (PK-40 Nippon Gosei Kagaku Kogyo) 10 parts Solvent (methanol) 10 parts Next, the nylon film was peeled off from the transfer sheet, and the water-soluble adhesive layer was moistened with water by a roll coating method. After the water-soluble adhesive layer was softened and activated, the pattern was transferred using a transfer pad in the same manner as in Example 4, and a delicate multicolor gradation pattern was obtained on the unglazed surface of the ceramic.

[Brief explanation of the drawing]

FIG. 1 is an enlarged schematic cross-sectional view of a transfer sheet used in the present invention, and FIG. 2 is a schematic enlarged cross-sectional view of another embodiment of the transfer sheet used in the present invention. In the figure, 1... Base sheet, 2... Elastomer film, 3... Design layer, 4, 4'... Transfer layer, 5, 5'...
Transfer sheet, 6...printing layer, 7...water-soluble adhesive layer.

Claims (1)

[Claims] 1. From a transfer sheet 5 formed by laminating a transfer layer 4 consisting of an elastomer film 2 and a water-soluble and adhesive pattern layer 3 on a non-stretchable base sheet 1 to the base sheet. 1 is peeled off, the transfer layer 4 is moistened, and the pattern layer 3 is placed in contact with the surface of the object to be transferred, and then a transfer pad is pressed from the elastomer film 2 side of the transfer layer 4, and the transfer layer 4 is moistened. A method for multicolor printing on a curved object, characterized in that the object to be transferred and the transfer layer 4 are brought into close contact with each other, and a pattern is printed on the surface of the object to be transferred. 2. The multicolor printing method on a curved surface object according to claim 1, wherein the pattern layer 3 is separated into a printing layer 6 and a water-soluble adhesive layer 7.