JPH0617040B2 - Method for manufacturing molded article having partially vapor-deposited hologram - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for manufacturing a molded product having a partially vapor-deposited hologram, and more specifically, an electrical product (portable cassette tape recorder, compact disc storage case). , Nameplates, etc.), cosmetic containers (compact cases, caps, etc.), and the like, to a partial hologram image.

[Conventional technology]

In the past, holograms have been used in the fields of display-related products and advertisements for the purpose of eye-catcher effect and unexpected effect due to three-dimensional effect, and they are also used as books, magazine covers, illustrations, and as gifts and novelties. ing.

As a method of duplicating this hologram, two methods are roughly known.

The first method is contact exposure and interferometry. Each of these methods is a method of newly forming a hologram using a photosensitive material.

The second method is a method of producing a surface relief type hologram by embossing on a smooth plastic material. Since this is a mechanical pressing method, it is relatively cheap in terms of cost, and mass production is possible. Suitable for As the plastic sheet of the material used in this method, conventionally, a thermoplastic sheet such as a rigid polyvinyl chloride sheet is used.

[Problems to be solved by the invention]

However, in the first method, an expensive photosensitive material is always required, and its cost is a large proportion of the hologram price. Therefore, the duplicated hologram is inevitably expensive and the time required for manufacturing is high. However, since the processing time of the light-sensitive material is relatively long, it becomes long and the productivity is poor.

In the second method, a commercially available hard polyvinyl chloride sheet used as a material is
Since it is manufactured by the extrusion method, the surface property is not always good, and in many cases, it is not satisfactory in terms of smoothness and uniformity. That is, when the smoothness of the surface of the base material is poor, there is a problem that a fine concavo-convex pattern of about 700 to 1,500 holograms / mm cannot be uniformly embossed with good reproducibility. Furthermore, in this method, heat and pressure are applied to the plate-shaped or sheet-shaped resin from the surface to reproduce the uneven pattern of the stamper plate, so sink marks and warpage phenomena are avoided in thick molded products. It was disqualified because it was not done. Further, in order to duplicate the hologram image on the molded product, there is only a method of sticking the duplicated hologram on the sheet-shaped product, which does not have a sense of unity with the molded product, and a satisfactory effect cannot be obtained. Therefore, the conventional technique has a problem that the usable range of the hologram is relatively limited.

[Means for solving problems]

The present invention has been made to solve the above-mentioned problems, and a hologram image stamper plate is fixed and placed in a mold for injection molding so as to be planar with respect to the inner surface of the mold, and then injected. Molded to form irregularities of the hologram image on the molded product, a water-soluble resin layer is formed on the portion where light reflection is unnecessary on the irregularity-formed surface side, and a light reflection layer is provided thereon by vapor deposition, followed by washing with water. By removing the water-soluble resin layer and the light-reflecting layer on the water-soluble resin layer, and further providing a protective layer if necessary, is a method for producing a molded article having a partially vapor-deposited hologram.

Next, the present invention will be described in detail with reference to the drawings. FIG. 1 is a sectional view conceptually showing the structure of an injection hologram according to the present invention, and FIGS. 2 to 6 are sectional views showing the method according to the present invention step by step.

According to the present invention, a hologram image forming stamper plate is fixed and placed in a mold for injection molding so as to be planar with respect to the inner surface of the mold, and a molten synthetic resin is filled in the mold by an injection molding method. Then, it is cooled and solidified to obtain a synthetic resin molded product (1). Here, to make the stamper plate planar with respect to the inner surface of the mold,
The stamper plate has a certain thickness, and it is for preventing the molded product from being dented by this thickness during injection molding. Specifically, the stamper plate and the inner surface of the mold are nested. Alternatively, the inner surface of the mold corresponding to the hologram image forming surface side may be entirely stamped. The molded product (1) has a hologram image existing on the stamper plate surface in the mold, that is, a fine concavo-convex pattern of 1 to 2 μ on the surface. (FIG. 2) As the synthetic resin, a transparent resin or an opaque resin can be used. When the transparent resin is used, the hologram image can be observed from the opposite side of the hologram image forming surface. Since the hologram image is observed through a transparent and thick resin layer, the original 3
Since the three-dimensional image is further passed through the layer having a different refractive index, it is possible to give the image a solid feeling. Examples of the transparent resin that can be used include polycarbonate, transparent polystyrene resin (hereinafter abbreviated as GPPS), acrylonitrile-
Styrene copolymer resin (hereinafter abbreviated as AS), polyester resin, polymethylmethacrylate resin (hereinafter PMM)
A), cellulose modified resin (cellulose propionate, etc.), and the like. Examples of the opaque resin include acrylonitrile-butanediene-styrene copolymer resin (hereinafter abbreviated as ABS resin) and impact-resistant styrene resin (hereinafter H).
(Abbreviated as IPS) or the like can be used. By selecting the injection molding conditions for these resins, the surface irregularity of the stamper plate can be reproducibly obtained on the molded product. The water-soluble resin layer (3) is partially provided on the hologram image forming surface (2) side of the molded product by a printing method such as silk screen printing or by applying a mask material and spray coating. (FIG. 3) The water-soluble resin layer (3) may be applied only to a portion which does not require light reflection. Examples of usable resins include partially saponified or completely saponified polyvinyl alcohol resin, methyl cellulose resin, ethyl cellulose resin. Etc. can be used. In addition, it is desirable to add an inorganic pigment such as barium sulfate, titanium oxide or calcium carbonate to the resin in order to improve the washing suitability in the subsequent step of washing with water. As the solvent for dissolving the resin, a composition mainly composed of water is desirable in order not to adversely affect the molded product, but an alcohol solvent may be added in consideration of suitability for printing application on a material to be printed. Further, in this step, it is possible to print characters, pictures, etc. in advance by a printing method such as silk screen or offset using a normal ink containing a coloring pigment. Then, after sufficiently drying, a light reflection layer (4) for light reflection is provided by vapor deposition. (FIG. 4) As the light reflection layer (4), a commonly used metal material such as aluminum, nickel, chrome, copper, titanium nitride, or zinc sulfide can be used, and required durability, Depending on the corrosion resistance or the required hue,
Just choose the type of metal. Other metal compounds such as metal oxides and metal sulfides can also be used depending on the required light reflection characteristics. As a vapor deposition method, a vacuum vapor deposition method, an ion plating method, or a sputtering method when an alloy such as titanium nitride is vapor deposited. The molded article having the light reflecting layer (4) deposited thereon is dipped in a water bath to remove the light reflecting layer (4) 'in the portion having the water-soluble resin layer (3), as shown in FIG. A molded article having a partially evaporated hologram is obtained. Further, if necessary, as shown in FIG. 6, a protective layer (5) is provided entirely or partially so as to cover the entire surface of the hologram image forming surface (2) and the light reflecting layer (4).

The molded product having the partially vapor-deposited hologram obtained as described above has a fine hologram pattern of 1300 to 1500 lines / mm, and the light-reflecting layer can be applied only to the portion where light reflection is necessary. It was possible to obtain a one-point hologram image, and to obtain a hologram image integrated with the molded product without deteriorating the original transparency or coloring effect of the molded product.

〔Example〕

 Next, the present invention will be described in detail based on examples.

(Example 1) A stamper plate on which a hologram image was formed was fixed and placed flat on the inner surface of the mold in an injection molding mold as a tape loading portion cover of a portable cassette tape recorder. Polycarbonate resin was injection-molded at a resin temperature of about 300 ° C. using the injection-molding die to obtain a transparent injection-molded product having irregularities of a hologram image. In addition to the portion having the hologram image on the hologram forming surface side of the injection-molded product, a water-soluble resin liquid having the following composition is diluted with a diluting solvent, if necessary, by a silk screen printing method, and printed to be water-soluble. After providing the resin layer, it was dried at 80 ° C. for 10 minutes.

<Composition> Polyvinyl alcohol resin 25 parts by weight Barium sulfate 50 parts by weight Water 15 parts by weight Isopropyl alcohol 10 parts by weight After depositing chrome on this, the water-soluble resin layer and the chrome on the water-soluble resin layer are removed. Washed off, and then mainly composed of acrylic polyol on the deposited layer side 2
A liquid-curable protective layer (transparent) was applied on the entire surface to obtain a molded product having a partially vapor-deposited hologram.

(Example 2) The hologram image forming stamper plate was fixed and placed flatly on the inner surface of the mold in the injection molding mold shown in Example 1, and the PMMA resin was placed in the mold. Injection molding was performed to obtain an injection molded product (6) having irregularities in the hologram image. On the hologram image forming surface (7) side of the injection molded product (6), P
Providing a printing layer (8) for letters, patterns, etc. using ordinary silk screen ink that adheres well to MMA, and then
The portions other than the hologram image forming surface (7) and its outer peripheral surface (9) and the character pattern (10) were silk screen printed using the water-soluble resin solution shown in Example 1. After sufficiently drying, aluminum is vapor-deposited from the side of the water-soluble resin solution, and then the portion printed with the water-soluble resin solution and the aluminum on it are removed by washing with water, as shown in FIG. An injection-molded article having various partial vapor deposition holograms was obtained. Further, the entire surface having the hologram as a protective layer was resin-coated. Since the obtained molded product is a transparent material, the inside can be seen through, and the hologram image forming surface (7) and its outer peripheral surface (9), a printing layer (8) for characters, patterns, etc., and further vapor deposition The appearance was excellent with the letter pattern (10) in aluminium.

〔The invention's effect〕

The partially vapor-deposited hologram molded product obtained by the method according to the present invention can be provided with a light-reflecting layer only in a portion where light reflection is necessary, so that a one-point hologram image can be obtained, and the transparency of the molded product is essentially It is a molded product with a hologram image, which does not deteriorate the coloring effect, has a sense of unity with the molded product, and has an appearance full of solid feeling. Also,
It becomes possible to show a partial hologram image on a three-dimensional molded product and a thick molded product, which was impossible with the conventional embossing method.
The field of use of holograms has expanded dramatically, and it can be used in the field of all synthetic resin molded products, and is an industrially extremely effective invention.

[Brief description of drawings]

The drawings show an embodiment of the present invention, FIG. 1 is a sectional view of a molded article according to the present invention, FIGS. 2 to 6 are sectional views for explaining a manufacturing process, and FIG. 7 is an embodiment. FIG. 3 is a conceptual view of the molded product observed from the front side with the hologram image printed surface as the back side. (1) …… Synthetic resin molded product (2) …… Holographic image forming surface (3) …… Water-soluble resin layer (4), (4) ′ …… Light reflecting layer (5) …… Protective layer (6) …… Injection molded product (7) …… Hologram image forming surface (8) …… Printing layer (9) …… Outer peripheral surface (10) …… Character pattern

Claims (1)

[Claims] 1. A hologram image forming stamper plate is fixed in a mold for injection molding so as to be planar with respect to the inner surface of the mold, placed and injection molded to form a hologram image on a molded product. The unevenness is formed, a water-soluble resin layer is formed on a portion where light reflection is unnecessary on the surface where the unevenness is formed, and the light-reflecting layer is provided thereon by vapor deposition. A method for producing a molded article having a partially vapor-deposited hologram, which comprises removing the light-reflecting layer on the layer and further providing a protective layer if necessary.