JPH0475792B2 - - Google Patents

Description

[Detailed Description of the Invention] Purpose of the Invention This invention relates to a decoration method using masking for synthetic resin molded products that require an aesthetic appearance, such as cosmetic containers and caps. To provide a method for creating patterns, characters, etc. clearly and beautifully.

Prior Art Conventionally, the surface of a synthetic resin molded product is masked with arbitrary letters or patterns using masking material, paper, tape, etc., and then paint is applied to the entire surface of the molded product, including the mask surface, to form a coating film. A masking painting method is known in which the mask and the coating film on the mask are then removed to form cut-out characters or patterns. In addition, as a method for masking synthetic resin molded products such as cosmetic containers and caps, which are the objects to which the method of the present invention is applied, the molded products are relatively small, so fine letters and designs are required, and the mask part and paint For reasons such as the requirement for sharpness of the boundaries between copies, printing using ink is generally used.

However, as conventional masking inks, water-soluble inks, alkaline-removable inks, and solvent-removable inks are mainly used. Therefore, in the case of water-soluble inks, masking inks can be removed by adding water or hot water to the alkaline-removable ink. In the case of ink, the molded article must be immersed in an alkaline aqueous solution, and in the case of solvent-removable ink, the molded article must be immersed in a solvent to dissolve and remove the masking ink. Therefore, with this method, not only does it take time to dissolve the masking ink, but it is also difficult to control the temperature and concentration of the solution, and in the case of solvent-removable ink, the coated areas other than the mask and the base material of the synthetic resin molded product are There are also limited types of solvents that can dissolve only the mask without attacking it, and furthermore, after dissolving the masking ink, separate cleaning must be performed to remove the masking ink and paint film that has eluted and adhered to the molded product. There was an inconvenience.

Structure of the present invention The molded products to which the decoration method of the present invention is applied are acrylonitrile-styrene (AS) resin, acrylic-butadiene styrene (ABS) resin, polypropylene (PP) resin, polyethylene terephthalate (PET) resin, polycarbonate resin, etc. It is a synthetic resin molded product that is molded into a predetermined shape. The structure of the present invention is as shown in the claims. In the following, this configuration will be explained first with reference to the drawings.

Figures 1 to 7 are explanatory views of the process of the present invention. First, the surface of the base material is cleaned, and then the desired shape is printed by screen printing, pad printing, etc. using ink that has poor adhesion to the base material 1. character or pattern mask 2
is formed on the surface of the base material (Fig. 1). Ink with poor adhesion here refers to ink that forms desired characters or patterns on the surface of the base material, but the adhesive strength between the formed ink layer and the base material is weak, and it easily peels off due to impact or deformation of the base material. An ink that has a certain degree of adhesive strength. Specifically, for example, in the case of polypropylene resin, an evaporative drying type resin whose main component is vinyl acrylic resin, etc. is applied to the unactivated surface of the resin base material.
Alternatively, if printing is performed using a two-component reactive ink such as epoxy or urethane-based ink, or a water-based ink whose main component is a water-soluble resin such as polyvinyl alcohol or ceramic, an ink layer will be formed, but it will not be activated. Since the surface of the polypropylene resin base material is non-polar, it does not adhere strongly to ink. In this way, desired characters or patterns can be created by using inks that basically have weak adhesion to synthetic resin substrates, or by using inks that contain additives such as silicone or slip agents that inhibit adhesion. Form a mask.

Next, the surface of the synthetic resin base material containing this mask is activated by gas flame, corona, glow or other discharge treatment (FIG. 2). This increases the adhesion between the next coating film and the synthetic resin base material. Specifically, for example, in the case of polypropylene resin, the treatment is applied uniformly to a surface tension of about 38 to 45 dynes/cm. This activation treatment is absolutely essential for polypropylene resin and polyethylene terephthalate (PET) resin. For other acrylonitrile styrene resins, acrylic butadiene styrene resins, polycarbonate resins, etc., it is possible to form a coating film even if this activation treatment is omitted, but in order to make the coating film adhere more firmly to the base material, Surface activation is also an essential requirement for these resins.

Next, paint the entire surface of the synthetic resin substrate, including the mask, with a paint that is colored in the desired color and is based on a resin that has strong adhesion to the synthetic resin substrate, such as vinyl, acrylic, or urethane. A film 3 is formed (FIG. 3). Next, the mask and the coating film formed on the mask are peeled off from the substrate by impact with high-pressure air, adhesive tape, or the like (FIG. 4). Note that 7 in FIG. 4 indicates a peeling means. Masks use ink that has a weak adhesion to the base material, and the surfaces of the base materials other than the mask are activated and then a coating is formed with a paint that has a strong adhesive strength to the base material, so the peeling mentioned above is not possible. During the operation, the mask and the coating film on the mask are easily peeled off from the base material, and the coating films other than the mask are strongly deposited on the base material and do not peel off, so that cut-out characters or pattern 8 in the mask portion are formed.

Next, the entire surface of the base material on which the mask-shaped exposed surface is formed is again activated by the above-mentioned activation means 6' (FIG. 5). This is done by increasing the adhesion between the decorative layer 4 such as printing or hot stamping applied to the exposed area after the mask is removed and the base material, and by attaching the transparent coating 5 applied after that to the base material 1. This is also carried out for the purpose of increasing the adhesive strength between the colored coating film 3 and the transparent coating film 5 formed previously. After this activation process, the mask is removed and the decorative layer 4 such as desired characters or patterns 8 is printed or hot stamped on the exposed portion.
(Figure 6).

Finally, the decorative layer, colored coating film,
A transparent paint is applied to the entire surface of the base material including the exposed portion to form a coating film 5 (FIG. 7). The paint that forms this transparent coating may be an acrylic, urethane, or other heat-drying type or two-component reaction type paint, but it is preferable to use acrylic resin or, if necessary, unsaturated polyester, epoxy, or urethane. An ultraviolet curable coating material whose main component is an acrylic resin modified by any of these methods and which can provide a coating film with a short curing time and high surface hardness is used.

Since the present invention is configured as described above, it brings about the following effects on the decorative processing process and products.

(1) The mask can be peeled off by blowing high-pressure air, etc., without immersing the base material in water, hot water, or solvent as in the conventional method to peel off the formed mask and the coating film on the mask. Therefore, the mask can be easily removed in a short time.

(2) The interlayer adhesion between the base material and the colored paint layer, the base material and the decorative layer, the base material and the transparent paint layer, and the colored paint layer and the transparent paint layer is activated. Very strong.

(3) Since the entire surface is finally covered with a transparent coating film, there is no difference in level between the base material and the colored coating layer, and between the base material and the decorative layer, resulting in a decorative body with a smooth surface and a good texture.

Example A bottle made of polyethylene terephthalate with a decorative decorative coating was obtained through the following steps (a) to (e).

(a) Molding a polyethylene terephthalate bottle using biaxial stretch blow molding.

(b) Clean and degrease the surface of the molded product with alcohol.

(c) Mask printing is performed using Sericol SP paint resist ink manufactured by Teikoku Ink Manufacturing Co., Ltd. using a screen printing machine.

(iv) Leave to dry at room temperature for 30 minutes.

(e) Activate with glow discharge treatment machine.

(Reduced pressure 0.1 to 0.2 Torr, discharge for 60 seconds) (f) Paint with white paint of the following composition (spray painting)
do.

Main ingredient UL-1027 manufactured by Mitsubishi Rayon Co., Ltd. White pigment Microlith White R-K manufactured by Ciba Geigy 0.5 parts (g) Dry at 40°C for 40 minutes.

(h) Peel off the mask and the coating film on the mask with 10 kg/cm ² of compressed air.

(li) Perform the same activation process as (e).

(v) Stamp the hot stamp text on the exposed part of the base material.

(Using PW silver foil made by Nakayama Kagaku Shikosho) (Le) Apply a transparent coating to the entire bottle.

(Spray painting using Mitsubishi Rayon UL-1010) (E) Pass under a high-pressure mercury lamp with an output of 80W/cm for 10 seconds to harden the coating and create a product.

The bottle thus obtained was very beautiful and had the appearance of a luxury product, and had an appearance that did not give the impression that it was a plastic product at all.

[Brief explanation of the drawing]

1 to 7 are explanatory diagrams showing the steps of the present invention. 1...Base material, 2...Mask, 3...Coating film, 4...
...Decorative layer, 5...Coating film, 6,6'...Discharge line,
7...Peeling means, 8...Pattern.

Claims (1)

[Claims] 1. A mask with a desired pattern is formed on the surface of a synthetic resin molded product using a masking material made of a substance that has poor adhesion to the base material of the molded product, and the molded product containing this mask is After activating the entire surface and forming a colored coating film with good adhesion to the base material on this entire surface, the mask is peeled off along with the coating film above it, and then the entire synthetic resin molding surface is activated again. It is characterized by forming appropriate character and/or pattern patterns on the treated surface by printing or transfer, and then applying colorless or colored transparent paint to the entire surface of the molded product to form a coating film. Decoration method for synthetic resin molded products. 2. The decoration method according to claim 1, wherein the molded product is relatively small.