JPS6238159B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for reliably forming an arbitrary pattern on the surface of an object without deforming it. Conventionally, the printing method disclosed in Japanese Patent Publication No. 52-41682 has been known as a method for forming arbitrary patterns on the surface of objects, but this method prints patterns on a thin film using paint, printing ink, etc. Next, the thin film is floated on a liquid with its pattern printed side facing up, and then an object is pressed against the thin film to allow it to settle wholly or partially into the liquid, thereby causing the liquid to sink. Since the pattern was transferred onto the surface of the object using hydraulic pressure, and the thin film was removed from the surface of the object after the transfer, the thin film used for pattern printing had the ability to swell, or expand, like a wafer. It is desirable that the thin film has good elasticity, flexibility, and softening properties, and especially when the surface of the object has complex irregularities, it is necessary for the thin film to stretch and develop while adhering closely to the irregular surface. When a thin film with such characteristics is floated on the water surface, the pattern printed on it will be significantly enlarged and deformed before it is transferred, so if a pattern exactly as printed (a fixed pattern) is obtained on the surface of the object, It is extremely difficult to achieve the intended purpose, and current printing technology has not reached the point where beautiful and colorful patterns can be printed on soft membranes such as wafers. Only simple printing patterns can be obtained. In particular, in the method of transferring a printed pattern together with this thin film, since the thin film prevents the printing pattern from being transferred to the finely uneven surface of the object, it is virtually impossible to print on a complex curved surface. Furthermore, the thin film must be removed by physical or chemical means after the printed pattern is transferred to the object.
This method has many disadvantages, such as the inconvenience of increasing the number of steps and the need to take precautions to prevent the transferred pattern from being damaged by the means for removing the thin film. Another method is to form a pattern on a water-soluble film, float it on the water surface with the pattern side facing up, apply adhesive on top of it, and press an object from above after the water-soluble film has dissolved. There is a method to transfer the pattern. However, even with this method, the water-soluble film does not dissolve and disappear completely, and a step to remove the residue may be necessary, and it takes a long time for the water-soluble film to dissolve in water. It had the disadvantage that it required The present invention has been made in view of the above points, and consists of floating a patterned synthetic resin sheet on a liquid with its pattern side facing down, and applying or spraying a solvent onto the synthetic resin sheet. By dissolving or swelling the synthetic resin sheet, it is intended to give the synthetic resin sheet the role of an adhesive to the object on which the pattern is to be formed. Next, the present invention will be explained in detail with reference to the drawings. First, as shown in FIG. 1, an arbitrary pattern 2 is applied to one side of a synthetic resin sheet 1, and the sheet is floated on a liquid 3 with the patterned side facing down. The synthetic resin sheet can be selected from among conventionally known films such as polypropylene film, polyethylene film, diacetate film, triacetate film, vinyl chloride film, polystyrene film, polycarbonate film, hydrochloric acid rubber film, and polyester film. Select arbitrarily depending on performance. The patterns are applied using conventionally known printing methods such as gravure printing and screen printing, and the inks used are salt-vinyl acetate, ethyl cellulose, nitrified cotton, polyester, acrylic, urethane, etc.
Arbitrarily selected from other known ones. Liquids include water, alkaline aqueous solution, acidic aqueous solution,
Aqueous solutions of water-soluble polymers and others can be used. Next, as shown in Fig. 2, a solvent 4 that can dissolve or swell the synthetic resin sheet and swell the ink applied to one side of the synthetic resin sheet is applied or sprayed onto the synthetic resin sheet floating on the liquid. The synthetic resin sheet is dissolved or swollen, and the ink is swollen. The solvent can be selected from acetone, ethyl acetate, toluene, methylene chloride, orthochlorophenol, a mixture of metacresol and tetrachloroethane, other conventionally known solvents, and mixtures of several types of these solvents for the synthetic resin sheet. Choose accordingly. Specific examples of combinations of synthetic resin sheets and solvents that dissolve or swell them are shown in the table below.

[Table] In order to improve the adhesive strength of the synthetic resin sheet after it has been dissolved or swelled, an adhesive may be mixed in the solvent. Note that even when the synthetic resin sheet is dissolved in a solvent, it does not diffuse into the liquid and still functions as a support for the pattern. Next, as shown in FIG. 3, when the object 5 on which the pattern is to be formed is pressed and submerged in the liquid, the melted or swollen synthetic resin sheet and the swollen pattern are transferred to the object by the liquid pressure. Adheres to the surface. At this time, the dissolved or swollen synthetic resin sheet plays the role of an adhesive, and as shown in FIG. 4, even when the object is pulled out of the liquid, the pattern is firmly adhered to the surface of the object. The object is preferably a plastic molded object, but by selecting the adhesive to be mixed in the solvent, patterns can be formed on objects made of any material other than wood base material. In addition, for the purpose of protecting the pattern and adjusting the gloss of the surface,
A surface resin layer 6 may also be provided as shown in FIG. Since the present invention forms a pattern on the surface of an object using the method described above, it has the following effects. (a) A pattern can be formed on the surface of a three-dimensional molded product. (b) Process time is shorter than conventional methods. (c) Compared to the conventional method, there is no distortion or blurring of the pattern. (d) By selecting a solvent, a wide range of synthetic resin sheets can be selected, and the best synthetic resin sheet can be selected depending on the printing effect and the properties of the object on which the pattern will be formed. (e) Since the synthetic resin sheet remains as an adhesive layer, a removal process is not necessary.

[Brief explanation of the drawing]

Figures 1 to 3 are explanatory diagrams showing an example of an embodiment of the present invention. Figure 1 shows a patterned synthetic resin sheet floating on a liquid, and Figure 2 shows a state in which a synthetic resin sheet with a pattern is sprayed on a liquid. Figure 3 is an explanatory diagram of the object pressed and submerged in the liquid, and Figure 4 is a cross-sectional view of the object with a pattern formed on its surface and a surface resin layer on it. . 1...Synthetic resin sheet, 2...Pattern, 3...Liquid, 4
...Solvent, 5...Object, 6...Surface resin layer.

Claims (1)

[Claims] 1 After applying a desired pattern to a synthetic resin sheet and floating it on a liquid with the pattern side facing down, apply or apply a solvent that can dissolve or swell the synthetic resin sheet and swell the ink that makes up the pattern. The synthetic resin sheet is dissolved or swollen by spraying, the ink is swollen, and the object on which the pattern is to be formed is then pressed onto the object and immersed in the liquid. A method of forming patterns on the surface of objects.