JPS63114636A - Plastic molded form to which metallic gloss is executed - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a plastic molded article coated with a metal vapor deposited layer to give it metallic luster.

[Conventional technology]

Shrink wrapping using packaging materials containing heat-shrinkable plastic film can be used to package the body or the entire body of glass bottles or plastic bottles for bottles, conditioners, cosmetics, etc., or to package audio materials such as video tapes, cassette tapes, etc.
It is widely used today in packaging for drinks, confectionery, and confectionery boxes.

In addition, a metal vapor deposition layer or a layer of ink with metallic luster can be applied to the body of a plastic molded product by transfer, or it can be applied directly to the body of a plastic molded product using a printing method such as silk screen printing. Therefore, efforts are being made to impart metallic luster and oxygen barrier properties.

In addition to the above-mentioned method of applying a metal vapor deposition layer to plastic molded products with poor barrier properties, there are also methods of coating polyvinylidene chloride resin to impart barrier properties, or ethylene-vinyl acetate copolymer. Barrier resins such as saponified materials and polyvinylidene chloride are co-injected with the main resin to produce multilayer containers with barrier properties.

[Problem that the invention seeks to solve]

However, when a conventional packaging material having a metal layer (for example, a metal vapor deposited layer) is used on a shrink plastic film, the metal vapor deposited layer cannot keep up with the shrinkage of the shrink plastic or film, resulting in whitening. Since it is not possible to use a metal vapor deposited layer, a method has been used in which an ink layer having metallic luster is used to produce metallic luster. However, since metallic ink does not have sufficient metallic luster to begin with, it is not possible to obtain a sufficient metallic luster.

In addition, metal vapor deposited layers are used in shrink packaging, such as in the packaging of video tapes and cassette tapes. I try not to.

In this case, it is not possible to metallize the entire package, resulting in poor appearance and appearance, and it is necessary to perform complicated processes such as busting and sealing, so packaging materials cannot be manufactured. There are many difficulties in the process and shrinkage process.

Recently, we have also seen shrunken packaging made of shrink plastic film with a metal vapor deposited layer on the body of cylindrical plastics and kubins such as shampoos and conditioners. In order to prevent whitening due to cracks in the vapor deposited layer in the front part, measures are taken to shrink only the rear and side parts and minimize the shrinkage in the front part.

In this case, in order to limit the part to be shrunk, it is necessary to align the parts thoroughly before shrinking, and since the part to be shrunk is partially shrunk, it is difficult to pass through the thermal open tunnel, making it extremely difficult to control the hot air. be.

In addition, the transfer method requires at least the cost of the transfer paper base material (release paper) 9 and is not suitable for the production of packaging containers.

In addition, the method of coating with a polyvinylidene chloride resin liquid requires time and effort for liquid preparation, coating, drying, etc., resulting in high costs.

In addition, the method of molding into multiple layers requires large-scale equipment, and unless it is made in large quantities, the cost will be high.

Therefore, the problem to be solved by the present invention is to provide a plastic molded product with metallic luster that can be manufactured at low cost regardless of the size of the lot and without requiring large-scale equipment. be.

[Means for solving problems]

As a result of research to solve the above-mentioned problems, the present inventor has found that by providing a metal vapor deposited layer on a heat-shrinkable resin film via a rubber primer, whitening of the metal vapor deposited layer can be prevented and a glossy appearance can be achieved. It was discovered that a metal vapor deposition layer can be applied to a plastic molded article, and the present invention was completed based on this knowledge.

That is, the first invention is ``a heat-shrinkable film in which a metal vapor-deposited layer is provided on a heat-shrinkable resin film through one or more rubber-based primer layers, with the metal vapor-deposited layer side facing inward. , a plastic molded product with a metallic luster, which is attached to the body of the plastic molded product and is made to adhere tightly to the body of the plastic molded product by heat-shrinking a heat-shrinkable film. .

Next, the second invention is a heat shrinkable resin film in which a metal vapor deposited layer is provided on a heat shrinkable resin film via one or more rubber-based primer layers, and a heat adhesive resin layer is further provided on the metal vapor deposited layer. The shrinkable film is attached to the body of the plastic molded product with the heat-adhesive resin layer side facing inward, and the heat-shrinkable film is heat-shrinked to tightly adhere to the body of the plastic molded product and the heat-adhesive film is attached to the body of the plastic molded product. A plastic molded product with a metallic luster made by bonding a resin layer to the body of the plastic molded product. ” is the gist.

So the first thing. In the second invention, the heat-shrinkable resin film may be printed.

Next, the first. The types of heat-shrinkable plastics and films that can be used in the second invention include polyvinyl chloride (PYC), polyethylene (PE), polypropylene (PP), and polyethylene terephthalate (PET).
), nylon (NY), polystyrene (PS), polyvinylidene chloride, ethylene-vinyl acetate copolymer, linear low-density polyethylene (single or laminate coextrusion films, etc.), and laminates. In order to increase this heat shrinkability, plastics and films can be subjected to treatments such as uniaxial stretching.

It is desirable to determine the thickness of the heat-shrinkable plastic or film by appropriately changing it depending on the use of the packaging material and the strength of other layers. For example, from the viewpoint of strength, it is necessary to have a thickness of 30 μm or more, but if it exceeds 100 μm, there is a risk that the cost will increase. The heat yield is, for example, 0 to 30% in the vertical direction and 15 to 60% in the horizontal direction.

The ink, which is optionally provided on the inner surface of the heat-shrinkable plastic film that is the outer layer, is a vehicle mixed with a pigment or dye colorant, a binder, a stabilizer, other additives, a solvent, or a diluent. Use the one made by Examples of this vehicle include ゛, ethylcellulose,
Nitrocellulose (nitrified cotton), ethylhydrokine cellulose, cellulose acetate propionate, cellulose derivatives such as cellulose acetate, polystyrene, polyα-
Styrene resins such as methylstyrene and styrene copolymer resins, acrylic resins or methacrylic resins such as polymethyl methacrylate, polyethyl methacrylate, polyethyl acrylate, polybutyl acrylate, etc. alone or copolymer resins, rosin, rosin-modified maleic acid Resin, rosin modified phenolic resin, rosin ester resin such as polymerized rosin, polyvinyl acetate resin, 'y malon resin, vinyl toluene resin, vinyl chloride resin, vinyl chloride/vinyl acetate copolymer, polyester resin, polyurethane resin (polyurethane + (including nitrified cotton, etc.), butyral resin, etc., one or more of them can be selected and used.

1st. The ink used in the second invention is selected based on suitability for printing on the substrate, adhesion, etc.

For example, when the heat-shrinkable film is polyvinyl chloride, rubber-based, acrylic-based, and vinyl chloride-based films can be used.

1st. In the second invention, the method of applying desired characters/patterns on the inner surface of the plastic film using ink, that is, the printing method includes gravure printing, offset printing, silk screen printing, offset gravure printing, electrostatic printing, jet printing, Ordinary methods such as dobrint may be used. Also.

The anti-whitening primer is formed using the same printing method as the ink.

Next, as the rubber-based primer for the can H8 which can be used in the first and second inventions, natural rubber-based, chlorinated rubber, etc. There are primers such as rubber-based primers, chloride rubber-based, cyclized rubber-based, hydrogen rubber-based, oxidized rubber-based, thion-anogen rubber-based, and rubber-based primers based on graft and block copolymers.

1st. And in the second invention, the rubber-based primer is
Preferably, there are two layers, and it is desirable that these two layers be changed as appropriate depending on the type of other layer with which each layer comes into contact. P.I.J.
Furthermore, when a rubber-based primer layer is provided between the printing ink layer and the aluminum metal vapor deposition layer, it is preferable to use a chlorinated rubber primer on the aluminum metal vapor deposition layer side and a cyclized rubber primer on the printing ink layer side. It is.

The layer thickness of the rubber-based primer layer can be changed as appropriate depending on the type of primer, the coating method, the type of other laminated materials, etc. For example, each layer has a thickness of 0.5 to 252
If the ratio is /m', the gravure coating method is easy. As a method for forming the rubber-based primer, a gravure coating method or the like is preferable.

This is because since it is coated on a heat-shrinkable plastic film, it is desirable that the same gravure coating be used for the printing ink layer and the primer layer.

The metal layer is formed on the surface of the rubber-based primer layer by vacuum evaporation method,
A desired metal film can be formed and provided by a sputtering method, an ion blating method, or the like. The metal used in this case is not particularly limited, and various metals can be used. Examples include gold, silver, copper, platinum, lead, zinc, cadmium, dichloride, cobalt, tin, aluminum, magnesium, titanium, beryllium, lithium, gallium, selenium, tellurium, chromium, manganese, antimony, bismuth, etc. .

During this vapor deposition, depending on necessity, a vapor deposition anchor and a sealite primer are applied to predetermined locations on the surface to be vapor-deposited, a metal film is formed on this treated surface by vacuum vapor deposition, and then the vapor-deposited film is removed from the areas where the sealant primer is applied by washing with water. It is also possible to carry out partial vapor deposition by performing a celite process to make the film.

The thickness of the metal layer is, for example, 100 to 900 A, preferably 300 to 600 A. If it is less than the above lower limit, the metallic luster will not be sufficient, whereas if it exceeds the above upper limit, cracks may occur during high shrinkage.

In the second invention, a thermoadhesive resin layer is provided inside the metal layer.

This thermal adhesive resin (hot melt adhesive) has a melting point of 6.
The temperature is 0 to 120°C, and when it is heat-shrinked, it tightly adheres to the outer wall of the plastic molded body. Examples of the heat-adhesive resin that can be used in the present invention include rosin-based resins such as gum rosin, drosin, and tall oil rosin;
Misoru wax, anhydrous lanolin wax, paraffin wax, microcrystalline wax, monk wax, ground wax, selenium, betroutan, vaseline, polyethylene wax, chlorinated paraffin, fatty acid amide, shellac wax, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, Examples include ethylene-methacdylic acid copolymer and Surlyn.

Next, in the first and second inventions, blow bottles and stretched bottles are used as plastic molded products.

Teupuka, tub-shaped containers, vacuum-formed products, etc. can be applied.

Next, the first. And the second shot 1! In AIc, a tube-shaped film or a sheet-shaped film can be used as the heat-shrinkable film. The high-frequency sealing method is used to bond sheet-like materials together into a cylinder.

There are methods such as solvent bonding and methods using adhesives.

After the heat-shrinkable film is formed into a cylindrical shape, the plastic molded product is put into the cylindrical shape, and heated by an appropriate method to cause heat shrinkage, so that the film is brought into close contact with the plastic molded product. can be obtained. Note that during this heat shrinkage, it is desirable that the heat shrinkage rate of the packaging material be 12% or less. This is because if the packaging material according to the present invention is used, the appearance and metallic luster are good even at a heat shrinkage rate of 15%, but whitening can be completely prevented at a heat shrinkage rate of 12% or less.

[For production]

It is believed that when the packaging material of the present invention is heat-shrinked, the rubber-based primer layer acts as a buffer material that absorbs the stress caused by the heat-shrinkage, thereby preventing the occurrence of cracks in the metal layer.

A remarkable anti-whitening effect can be obtained when the rubber-based primer layer is formed into a plurality of layers, particularly when it is formed into two layers consisting of an outer cyclized rubber-based primer layer and an inner chlorinated rubber-based primer layer.

Although this mechanism is not necessarily clear, the stress caused by heat shrinkage can be gradually alleviated by laminating a chlorinated rubber primer layer and a cyclized rubber primer layer in this order. Furthermore, it is thought that misalignment occurs between the two types of primer layers due to stress relaxation.

In particular, the lamination of the chlorinated rubber primer layer/cyclized rubber primer layer is considered to be the best combination due to the flexibility, hardness, heat deformability, etc. of the primer layer. Note that this explanation is for a better understanding of the invention and is not intended to limit the scope of the invention.

[Example] Example 1 A pattern was printed on heat-shrinkable vinyl chloride 30 μm using nitrated cotton-bolyamide ink, and a cyclized rubber primer was printed twice using the gravure printing method, and then A was vacuum-deposited to a thickness of 50 OA. A heat-shrinkable film was obtained. Next, the vapor-deposited parts at both ends were subjected to f-coching by buster processing, and the heat-shrinkable film was made into a tube by high-frequency sealing in the form of an envelope.

Content: 2000H made of ethylene vinyl acetate copolymer
When the film was placed over a tube container and heat-treated at 120° C. for 10 minutes, the heat-shrinkable film could be fixed to the tube, and a tube container with good metallic luster could be obtained.

Example 2 Heat-shrinkable vinyl chloride resin (PVC) 5Qμ/printing layer/cyclized rubber primer i 3 Val/aluminum vapor deposition layer 4
00A/Ethylene-vinyl acetate copolymer layer 322e, the heat-shrinkable film with a coral structure is made into a tube, and inside the tube, 0250CC made of high-density polyethylene 7 (HDP) 13) is placed.
Insert a blow bottle with the same amount of content as shown in Figure 1, heat shrink it for 5 minutes in a heat-open oven at 150°C, and turn the bottle (1
) A container was obtained in which the heat-shrinkable film (2) was tightly attached to the body of the container.

Example 3 The same procedure as in Example 2 was carried out, except that a blow bottle made of vinyl chloride resin (P'll'C) and having an internal capacity of 5 oocc was used as the plastic molded product.

Example 4 The same procedure as in Example 2 was carried out except that a stretched blow bottle made of polyester (PET) and having an internal capacity of 1000 Ω was used as the plastic molded product.

Example 5 The same procedure as in Example 2 was carried out, except that a blow bottle containing 50 CC of ethylene vinyl acetate copolymer (EVA) fi was used.

Example 6 The same procedure as in Example 2 was carried out, except that a vacuum-formed cup made of polystyrene and having a content of 180 cc ffi was used as the plastic molded product.

The products of Examples 2 to 6 had beautiful metallic luster and were beautiful.

Furthermore, as shown in the table below, it had excellent oxygen barrier properties.

Table: [Effects of the Invention] As detailed above, the product according to the present invention has excellent metallic luster.

Moreover, it can be easily obtained at low cost without using large-scale equipment.

Furthermore, barrier properties can be imparted more easily than when coating with PVDC or the like.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the bottle of Example 2.

Claims (4)

[Claims] (1) A heat-shrinkable film, which is a heat-shrinkable resin film with a metal vapor-deposited layer interposed through one or more rubber-based primer layers, is placed on a plastic molded product by placing the metal-vapor-deposited layer side facing inward. A plastic molded product with a metallic luster that is attached to the body of the plastic molded product and is made by heat-shrinking a heat-shrinkable film to tightly adhere to the body of the plastic molded product. (2) The plastic molded article with metallic luster according to claim 1, wherein the heat-shrinkable resin film is a heat-shrinkable resin film having a printed layer. (3) A heat-shrinkable film in which a metal vapor-deposited layer is provided on a heat-shrinkable resin film via one or more rubber-based primer layers, and a heat-adhesive resin layer is further provided on the metal-deposited layer, Attach the heat-adhesive resin layer to the body of the plastic molded product with the side facing inward, and heat-shrink the heat-shrinkable film to make it adhere tightly to the body of the plastic molded product, and mold the heat-adhesive resin layer into the plastic mold. A plastic molded product with a metallic luster that is glued to the body of the product. (4) The plastic molded article with metallic luster according to claim 3, wherein the heat-shrinkable resin film is a heat-shrinkable resin film having a printed layer.