JPS635253B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for manufacturing a decorated molded article, and particularly to a method for easily manufacturing a three-dimensional molded article with a good design.

(Prior Art and Problems) Conventionally, a method of manufacturing a molded article by vacuum forming a plastic sheet such as an acrylic plate has been widely used. However, when a pattern is printed on a plastic sheet before molding or when printed films are laminated in order to apply a pattern to this molded product, peeling tends to occur due to the difference in elongation during molding. Furthermore, methods for painting after molding include spraying ink and transferring an ink film onto release paper, but in either case it is not possible to apply a precise design to a curved surface.

(Means for Solving the Problems) The present invention was made under these circumstances, and transfer paper printed with ink containing a sublimable dye is placed on an acrylic plate, and heat and pressure is applied to perform sublimation transfer. This method of producing a painted molded article is characterized in that the coated article is then heated to a temperature lower than the transfer temperature and vacuum formed.

(Explanation of Examples) The dyes that can be used in the present invention are dyes that can be sublimated and transferred at 190°C to 230°C, such as Sumikalon Yellow.
Examples include FG (manufactured by Sumitomo Chemical Co., Ltd.) and Miketone Polyester Red 2BSF (manufactured by Mitsui Toatsu Chemical Co., Ltd.).
These dyes can be made into ink using known methods. In other words, an ink can be made by using a hydrophilic resin such as a water-soluble acrylic resin or ethyl cellulose as a binder and kneading it with a dye, a binder, and a solvent such as water.The ink can then be printed and transferred onto paper, etc. using flexography or gravure printing. You can get paper.

In the present invention, the sublimation transfer temperature is 190-230°C, and the molding temperature is 160-190°C.

If the molding temperature is higher than the transfer temperature, re-sublimation of the dye may occur, so the molding temperature must necessarily be lower than this.

For this reason, since the acrylic plate softens at the heating temperature during transfer, it is desirable to cool the acrylic plate under pressure after transfer and perform the next step of vacuum forming while maintaining a flat state.

In sublimation transfer, for example, as shown in FIG. 1, a cushion material 2, an acrylic plate 3, a transfer paper 4, a dye-impermeable sheet 5 such as Teflon, and a heating plate 6 are stacked on a substrate 1 in this order. This can be done by heating and pressurizing at 210°C for 40 seconds. Since the transfer is performed by sublimating and penetrating the dye into the acrylic plate 3, the pattern does not peel off from the acrylic plate 3 during molding, unlike when an ink film is transferred.

Vacuum forming can be performed by a conventional method.
It is necessary to use an acrylic plate due to the relationship between the sublimation transfer temperature and the vacuum forming temperature; with other plastic sheets, the dye may re-sublimate depending on the forming temperature, or the forming itself becomes difficult.

(Test example) Miketon Polyester Red 2BSF 13 parts by weight Water-soluble acrylic resin (solid content 30%) 20 〃 Water 〃 Mix the above ingredients well with a high-speed mixer to make it homogeneous to make a flexo printing ink.
It was printed on high-quality paper and used as a transfer paper.

As shown in FIG. 1, an acrylic plate with a thickness of about 2 mm is placed on a base 1 with a cushion material 2 interposed therebetween.
The above transfer paper was placed on top of this, and further heated at 210°C for 40 seconds with a heating plate 6 through a Teflon sheet 5.
It was allowed to cool down to 40°C in this state (while still being pressurized).

Thereafter, the transfer paper was removed and the acrylic plate was taken out, and the acrylic plate was vacuum-formed into a tray shape at a temperature of 170° C. according to a conventional method.

The molded product obtained had a good tray shape and a detailed pattern even on the curved surface.

(Effects) The present invention has succeeded in applying a delicate pattern by using a sublimation transfer method as a painting method and by painting before molding, and by using an acrylic plate after sublimation transfer at a high temperature. Succeeded in vacuum forming at low temperature without re-sublimation,
They have succeeded in producing vacuum-formed products with elaborate designs.

[Brief explanation of the drawing]

The drawings show examples of the present invention, and FIG. 1 is an explanatory diagram showing a sublimation transfer process. 1...Base, 2...Cushion material, 3...Acrylic board, 4...Transfer paper, 5...Dye-impermeable sheet.

Claims (1)

[Claims] 1 Transfer paper printed with ink containing sublimable dye is placed on an acrylic plate, heated and pressed to perform sublimation transfer, cooled under pressure, heated the acrylic plate to a temperature lower than the transfer temperature, and vacuum formed. A method for manufacturing a painted molded article, characterized by: