JP5261753B2 - Resin molded product excellent in design, metallic luster, and insulation, and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin molded product which includes a fancy appearance with metallic luster and also includes insulating property sufficient for the use as a cellular phone casing or the like, and a method for manufacturing the same. <P>SOLUTION: The resin molded product includes an irregular weave pattern and a metal thin film formed on a surface thereof. The irregular weave pattern includes a cloth surface design organized by yarns 200-2,000 deniers in thickness, and the metal thin film includes metallic luster with a film thickness of 200-800 &angst;, and is formed along the irregularity. The metal thin film includes minute cracks that is not visually confirmed and includes insulating property such that the metallic luster is not changed before and after a treatment of 1,000 W&times;3 s by microwave oven. The resin molded product is manufactured by mutually superposing a cloth having the weave pattern on the surface and a transfer film having the metal thin film, and performing resin molding with the metal thin film side being contact with a resin surface. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a resin molded product having both a design property, a metallic luster, and an insulating property that does not change the metallic luster before and after a 1000 W × 3 second treatment with a microwave oven, and a specific uneven texture pattern, and It relates to the manufacturing method.

Various resin molded products having a metal thin film such as a Sn thin film or an Al thin film formed on the surface are known as decorative ones. However, since they all have electrical conductivity, they cannot be used for electronic device boxes. There wasn't.
Usually, since an Al thin film is excellent in electrical conductivity, a resin molded product having an Al thin film formed on the surface thereof does not have an insulating property with a metallic luster.
In addition, the Sn thin film is an island-like metal thin film having a thickness of less than 300 mm and has an insulating property and a certain level of metallic luster, but in order to further improve the metallic luster, the island shape becomes insulating when the film thickness is 300 mm or larger. Therefore, the resin molded product having the Sn thin film formed on the surface did not have an insulating property in a state of metallic luster.

  Separately, as a method for producing an injection-molded product having excellent design properties, there is an attempt to obtain a resin-molded product in which a cloth pattern for organizing the cloth surface is formed on the surface by using a cloth. For example, Patent Document 1 discloses that a transfer film with a pattern and a fiber material are polymerized and placed in an injection mold so that the transfer film faces the injection hole, and then synthesized from the injection hole. Resin is injection-molded, and the transfer film and fiber material are peeled off from the molded product with the transfer film and fiber material attached to the surface. A method for obtaining an injection-molded article is disclosed, and it is also shown that a vapor-deposited transfer film with aluminum vapor deposition can be used as the transfer film.

As shown in the examples of Patent Document 1, when ordinary nylon taffeta or polyester taffeta (thickness: about 40 denier, density: 85 to 130 / inch) is used as a fiber material, vapor deposition transfer is performed as a transfer film. When a film is used, it becomes a molded product having electrical conductivity, so that it can only be used as a cosmetic container or the like and cannot be used for an electrical component container (electronic device box) (Example of Patent Document 1). 2). Therefore, in order to obtain a container for an electrical component in Patent Document 1, only a fiber pattern was transferred using a simple transparent film as a transfer film (see Example 3 of Patent Document 1).
That is, in the prior art, a resin molded product having design properties, metallic luster, and insulation, and a resin molded product that can be used for a box of an electronic device cannot be obtained.

JP-A-4-261819

  The present invention is a resin molded product having an uneven texture pattern and a metal thin film formed on the surface, and has an excellent design property, metallic luster, and insulation, and a box for an electronic device such as a box for a mobile phone. An object of the present invention is to provide a resin molded product that can be used in the manufacturing process and a method for producing the same.

The inventor of the present invention is a resin molded product having an uneven cloth pattern and a metal thin film formed on the surface, and has a design on the surface of the cloth in which the uneven cloth pattern is structured with yarns having a thickness of 200 to 2000 denier. When the metal thin film is formed as a metal thin film having a metallic luster with a film thickness of 200 to 800 mm along the irregularities, there is a fine crack that cannot be visually confirmed in the metal thin film. I found out.
Furthermore, because of the presence of the fine cracks, the metal thin film is not destroyed even by a 1000 W × 3 second treatment by a microwave oven, and the resin molded product has an insulating property that does not change the metallic luster before and after the treatment. As a result, it has become possible to provide a practical resin molded product that has excellent design, metallic luster, and insulation and can be used in a box of an electronic device such as a box of a mobile phone.

  The resin molded product of the present invention is a resin molded product having an uneven texture pattern and a metal thin film formed on the surface, and the uneven texture pattern is a surface of a fabric surface composed of yarns having a thickness of 200 denier to 2000 denier. The metal thin film is a metal thin film having a metallic luster having a thickness of 200 to 800 mm and is formed along the irregularities, and the metal thin film has fine cracks that cannot be visually confirmed. It is a resin molded product that has both design properties, metallic luster, and insulating properties, and has an insulating property that does not change the metallic luster before and after the treatment of 1000 W x 3 seconds by a microwave oven. is there.

The fabric pattern is a fabric pattern having a design on the surface of the fabric organized with yarns having a thickness of 200 denier to 2000 denier, and the yarn density of the yarn is 10 / inch to 100 / inch in both longitudinal and lateral directions. A texture pattern on the surface of the cloth structured with yarns in the range of is preferably used.
The texture pattern according to the present invention may be a texture pattern of the cloth surface itself, which is composed of yarns having a thickness or thread density in the above-mentioned range, but by transferring the texture pattern on the cloth surface. The cloth surface pattern formed may be a texture pattern (unevenness or pattern on the cloth surface (for example, an embroidery pattern) formed on the opposite sides of the unevenness or pattern as in a negative and positive relationship). Both of the above texture patterns are included.

  As the metal thin film, it is preferable to use a metal thin film selected from the group consisting of Sn, Bi, Al, Zn, In, and alloys thereof, and can be appropriately selected and used depending on the desired level of metallic luster and insulation. .

  The film thickness of the metal thin film may be 200 mm to 800 mm. However, depending on the type of metal, there is a metal having a large conductivity or an insufficient metal luster. In order to maintain in the excellent range, it is more preferable that it is 400 to 600 inches.

  As the molding resin used for the resin molded product, any resin that can be used for the production of a normal molded product can be used, and it may be a thermoplastic resin or a thermosetting resin. For example, ABS (acrylonitrile / butadiene / styrene) resin, AS (acrylonitrile / styrene copolymer) resin, PP (polypropylene) resin, PE (polyethylene) resin, or the like is preferably used for manufacturing a box of an electronic device.

Moreover, in order to improve protection and design property of a metal thin film, you may form the protective layer which consists of resin on the metal thin film, and the colored layer which colored this protective layer with the coloring agent.
Furthermore, an adhesive layer may be provided on the opposite side of the surface of the metal thin film as desired to improve the adhesion between the molding resin and the metal thin film.

Such a resin molded product of the present invention can be stably manufactured with high quality by the following manufacturing method of the present invention.
First, a transfer film in which a cloth having a texture pattern composed of yarns having a thickness of 200 denier to 2000 denier on the surface and a metal thin film having a thickness of at least 200 mm to 800 mm formed on a base film via a release layer, Laminate and arrange the transfer film so that the metal thin film side is on the outside (so that the cloth and the base film are in contact), contact the metal thin film side of the transfer film with the molding resin, and the unevenness of the texture pattern on the resin surface After forming the metal film and simultaneously transferring the metal thin film, the resin molded product of the present invention can be produced by peeling the cloth and the base film.

  In such a manufacturing method of the present invention, since the resin for molding does not directly contact the cloth, the cloth can be stably peeled after molding without the resin being eaten into the cloth at the time of molding. You can choose from a wide range. In addition, since the stress at the time of molding is dispersed by interposing the cloth, the metal thin film is not uneven and large cracks that can be visually confirmed do not occur, so there is no problem in appearance and injection. In the case of molding using a mold such as molding, it is possible to deal with complicated molds, and it is possible to provide a resin molded product excellent in design, metal luster, and insulation.

In addition, in order to obtain the desired texture pattern in the present invention, any cloth in which the texture on the cloth surface is structured using yarns having a thickness of 200 denier to 2000 denier can be used. In particular, it is preferable to use a fabric having a yarn density of 10 to 100 yarns per inch in both length and width, and 600 denier to 1500 denier yarns having a density of 15 to 40 yarns per inch. Particularly preferred is the use of a cloth.
Here, the yarn density means the number of yarns constituting the cloth on the fabric surface, and means the number of yarns existing between 1 inch in the longitudinal direction or the transverse direction. For example, the density of the weft of a woven fabric in which two weft-aligned yarns are used as wefts and 5 textures are inserted between 1 inch is 10 / inch.

As the cloth, any of woven cloth, knitted cloth, embroidery cloth and the like can be used.
The embroidery cloth is woven or knitted on the entire surface or part of the embroidery. The embroidery is also a thread having a thickness of 200 denier to 2000 denier, and the thread density is 10 / inch in both length and width. It is preferable from the point of insulation that the embroidery is structured with yarns in the range of 80 / inch.
When designed so that the thread thickness and thread density on the surface of woven fabric, knitted fabric, and embroidery fabric are within the above ranges, the metal thin film formed on the surface of the resin molded product with uneven texture is visually observed. In other words, a fine crack that cannot be confirmed by the above method occurs, and the resin molded product is excellent in metallic luster and design properties, but can also have a desired insulating property.

In addition, as a molding method of a resin molded product, any normal method of using a mold and forming the surface shape of the resin molded product according to the mold can be applied. For example, injection molding, compression molding, transfer molding There are methods such as blow molding, extrusion molding, and vacuum molding.
The injection molding will be described in detail as an example. A cloth having a texture pattern composed of yarns having a thickness of 200 to 2000 denier on the surface, and a metal having a film thickness of at least 200 to 800 mm via a release layer on the base film. The transfer film on which the thin film is formed is laminated on an injection mold so that the metal thin film side of the transfer film is on the outside and the injection hole side, and the molding resin is formed on the metal thin film side of the transfer film from the injection hole. After the resin is injected and brought into contact, the cloth and the base film are peeled off to obtain the resin molded product of the present invention.
Further, the cloth, the transfer film, and the plate-shaped molding resin are laminated in this order so that the metal thin film side of the transfer film and the plate-shaped molding resin are in contact with each other. After applying heat and pressure, heat roll molding that peels off the cloth and the base film, and further applying heat and pressure from above and below (both sides) with a plurality of the laminates sandwiched between metal plates, A molding method such as multi-stage press molding for peeling the cloth and the base film can also be exemplified.

  As the resin for molding, as in the resin used for the resin molded product, any resin that can be used for manufacturing a normal molded product can be used, and it may be a thermoplastic resin or a thermosetting resin. . For example, ABS (acrylonitrile / butadiene / styrene resin), AS (acrylonitrile / styrene copolymer), PP (polypropylene resin), PE (polyethylene resin), or the like is preferably used for manufacturing a box of an electronic device.

  As described above, any of woven fabric, knitted fabric, embroidery fabric, etc. can be used as the fabric, but a plain weave, a regular weave, a regular oblique weave, a plain weave, a satin weave and an oblique weave are assembled. It is preferable to use one having a coarsely floating structure, such as a combined change weave weave, knotted weave, warp weave and weft weave, and knit. The embroidery cloth may be configured so that the thickness and density of the embroidery thread forming the surface texture are within a predetermined range.

Any known transfer film can be used. For example, in order to enhance the protection and design properties of the metal thin film formed directly on the one side of the base film through a release layer made of a resin having releasability or the like, the release layer and the metal thin film A protective layer made of a resin or a colored layer obtained by coloring the protective layer with a colorant may be used.
Furthermore, an adhesive layer may be provided on the metal thin film as desired to improve the adhesion between the molding resin of the resin molded product of the present invention and the metal thin film.
As the base film, any film used for the production of a normal transfer film can be used, but because it is arranged along the inner surface of the mold, it is a plastic film such as a polyethylene terephthalate film. preferable.
For the release layer, any material conventionally used as a release layer for transfer films can be used, and acrylic resins, waxes, and the like can be used.
For the protective layer and the colored layer, any of the materials conventionally used for the protective layer and colored layer of the transfer film can be used. Polyester resin, acrylic resin, and resins and dyes in which a curing agent such as isocyanate is mixed. Colorants such as pigments can be used.

  The present invention relates to a resin molded product having both a design property, a metallic luster, and an insulating property that does not change the metallic luster before and after a 1000 W × 3 second treatment with a microwave oven, and a specific uneven texture pattern, and This is a manufacturing method, and it is possible to provide a resin molded product having an insulating property that can be used for a box of an electronic device such as a box of a mobile phone. It should be noted that the fact that the metallic luster does not change before and after the processing of 1000 W × 3 seconds by the microwave oven is necessary as an insulating property in the box of the electronic device, but further 1000 W × 5 seconds by the microwave oven. Although it is preferable that the metallic luster does not change even by this treatment, in the present invention, as shown in the Examples, it is possible to easily provide a resin molded product that is suitable for the treatment conditions.

Next, the present invention will be described in more detail based on examples.
<Example 1>
A transfer film consisting of a base film (polyethylene terephthalate film) / release layer / protective layer / Sn thin film / adhesive layer, with the Sn thin film thickness changed to 100 mm, 200 mm, 400 mm, 600 mm, 800 mm, and 900 mm. Each transfer film was prepared, and the base film side was the inside, the Sn thin film side was the outside, and 1500 denier polyester yarn was woven in a basket with a yarn density of length / width = 17/15 yarns (both of the backgrounds were 2 yarns) The sheet is laminated with a woven fabric made of a regular knitted fabric made of an aligned yarn, and the Sn thin film side of the transfer film faces the injection hole of the injection molding resin in the injection molding die along the die. Then, the ABS resin was injection molded from the injection hole, and then the woven fabric and the base film were peeled from the molded product taken out from the mold.
As a result, a resin molded product is obtained in which the surface of each resin molded product has an uneven texture pattern on the surface of the woven fabric and an adhesive layer, an Sn thin film, and a protective layer are sequentially formed on the entire surface along the unevenness. I was able to.
Table 1 shows the results of evaluating the physical properties of the obtained resin molded product. From this result, when a transfer film having a Sn thin film thickness of 200 to 800 mm is used, a resin molded product having excellent design and texture with a textured pattern due to the woven structure of the woven fabric on the surface is insulated. It turns out that it is obtained in the state which has sex.
However, when the film thickness of the Sn thin film is 100 mm, it is not possible to obtain a resin molded product having a metallic luster. When the film thickness of the Sn thin film is too thick as 900 mm, a resin molded product having a desired insulating property cannot be obtained. Couldn't get.

However, the evaluation in Table 1 is based on the following criteria.
<Insulation>
Changes in metallic luster were examined before and after 1000 W microwave treatment.
◎ Even after 5 seconds of treatment, the Sn thin film is not destroyed and the metallic luster does not change.
○ In the treatment for 3 seconds, the Sn thin film was not destroyed and the metallic luster did not change, but in the treatment for 5 seconds, the Sn thin film was partially broken and the metallic luster was partially reduced.
Δ The Sn thin film was not destroyed instantaneously and the metallic luster did not change, but the Sn thin film was partially broken by the treatment for 3 seconds, and the metallic luster was partially reduced.
X Most of the Sn thin film was instantaneously destroyed, and the overall metallic luster was lowered.
<Metallic luster>
The appearance was evaluated according to the following criteria by visual inspection.
◎ Excellent metallic luster.
○ Slightly dark metallic luster, slightly inferior to metallic luster.
× No metallic luster.

<Example 2>
A transfer film consisting of a base film (polyethylene terephthalate film) / release layer / protective layer / Al thin film / adhesive layer, with the Al thin film thickness changed to 100 mm, 200 mm, 400 mm, 600 mm, 800 mm and 900 mm. Prepare each transfer film, basket weave with yarn density of length / width = 17/15 yarns of polyester yarn of 1500 denier with the base film side on the inside and the Al thin film side on the outside Are laminated with a woven fabric made of a regular diagonal weave), and the Al thin film side of the transfer film faces the injection hole of the injection molding resin in the injection molding die along the die. Then, the ABS resin was injection molded from the injection hole, and then the woven fabric and the base film were peeled from the molded product taken out from the mold.
As a result, a resin molded product is obtained in which the surface of each resin molded product has an uneven texture pattern on the surface of the woven fabric, and an adhesive layer, an Al thin film, and a protective layer are sequentially formed on the entire surface along the unevenness. I was able to.
The physical properties of the obtained resin molded product are shown in Table 2 (evaluation criteria are the same as those in Table 1. However, Sn thin film is replaced with Al thin film and applied). From this result, when a transfer film having an Al thin film thickness of 200 to 800 mm is used, a resin molded product having an uneven pattern due to the woven structure of the woven fabric on the surface and an excellent metallic luster is insulative. It turns out that it is obtained in the state which has.
However, when the film thickness of the Al thin film is 100 mm, a resin molded product having a metallic luster cannot be obtained. When the film thickness of the Al thin film is too thick as 900 mm, a resin molded product having insulating properties can be obtained. I could not.

<Example 3>
Similar to Example 1 using a transfer film composed of a base film (polyethylene terephthalate film) / release layer / protective layer / 600 mm thick Sn thin film / adhesive layer and a plain weave woven fabric shown in Table 3 In this way, on the surface of each resin molded product, there is a resin pattern on which the surface of the woven fabric is uneven, and an adhesive layer, an Sn thin film, and a protective layer are sequentially formed on the entire surface along the unevenness. I was able to get it.
Table 3 shows the physical properties of the obtained resin molded product. Insulation and metallic luster were evaluated according to the same criteria as in Table 1. Moreover, the evaluation of the crack in the metal thin film on the surface was based on visual observation, and was in accordance with the following criteria.
◎ There are no large cracks, and there is no problem in practical use as the appearance of resin molded products.
○ There are slight cracks, but there is no practical problem with the appearance of resin molded products.
Δ: The cracks are conspicuous and there is a practical problem as the appearance of the resin molded product.

When a woven fabric having a yarn denier of 200 to 2000 and a yarn density of 100 to 10 yarns / inch was used, a resin molded product having excellent design and metallic luster and having an insulating property was obtained. In addition, there was no practical problem with the appearance. In particular, when a woven fabric woven from 600 denier yarn at a yarn density of 40 / inch or a woven fabric woven from 1500 denier yarn at a yarn density of 15 / inch is used, the design properties and metallic luster Both of them were excellent, and an excellent resin molded product was obtained in terms of insulation. There was no practical problem with respect to the appearance.
However, when a thin thread of less than 200 denier is used, the resin does not have insulation, and when a thick thread of more than 2000 denier is used, cracks are conspicuous and the appearance is deteriorated, and the resin does not have insulation. Only molded products could be obtained.

<Example 4>
A transfer film consisting of a base film (polyethylene terephthalate film) / release layer / protective layer / 600 nm thick Sn vapor deposition layer / adhesive layer and a woven fabric used in Example 1 with a 300 denier polyester thread embroidered with a floral pattern (Thread density of the embroidery part: 80 / inch in both length and width) An embroidery cloth is prepared, and the transfer film is laminated on the embroidery cloth so that the embroidery surface is on the transfer film side. Next, along the mold, the transfer film is arranged so that the Sn thin film side faces the injection hole of the injection molding resin, and ABS resin is injection molded from the injection hole, and then removed from the mold The embroidery cloth and the base film were peeled from the product.
As a result, the surface of the resin molded product has an uneven texture pattern on the surface of the embroidery cloth (the flower pattern by embroidery and the non-embroidered portion are the uneven texture pattern on the surface of the woven cloth similar to Example 1) and The resin molded product of the present invention in which the adhesive layer, the Sn thin film, and the protective layer were sequentially formed on the entire surface along the unevenness could be obtained.

  Since the resin molded product obtained in each example according to the present invention has a design property, a metallic luster, and an insulation property, all of them are used for a mobile phone case, a personal computer, a game machine, a front panel of home appliances, and the like. It could be used practically.

Claims (9)

  A resin molded product having an uneven cloth pattern and a metal thin film formed on the surface, wherein the uneven cloth pattern is a cloth pattern having a design property of the cloth surface composed of yarns having a thickness of 200 denier to 2000 denier. The metal thin film has a metallic luster with a thickness of 200 to 800 mm and is formed along the irregularities, and the metal thin film has minute cracks that cannot be visually confirmed, and is 1000 W × by a microwave oven. A resin molded product having both design properties, metallic luster, and insulating properties, having an insulating property that does not change the metallic luster before and after the treatment for 3 seconds.   2. The resin molded product according to claim 1, wherein the uneven texture pattern is a texture pattern on the surface of the fabric organized by yarns having a yarn density in a range of 10 yarns / inch to 100 yarns / inch, both vertically and horizontally. .   The resin molded product according to claim 1 or 2, wherein the metal thin film is a metal thin film selected from the group consisting of Sn, Bi, Al, Zn, In, and alloys thereof.   The resin molded product according to any one of claims 1 to 3, wherein the metal thin film has a thickness of 400 to 600 mm.   It is a manufacturing method of the resin molded product of Claim 1, Comprising: The cloth which has the texture pattern organized by the thread | yarn of thickness 200 denier-2000 denier on the surface, and at least film thickness through a mold release layer on a base film A transfer film on which a metal thin film of 200 to 800 mm is formed is laminated so that the metal thin film side of the transfer film is on the outside, a molding resin is brought into contact with the metal thin film side of the transfer film, and the fabric surface Resin molding having both design properties, metallic luster, and insulating properties, wherein pattern irregularities are formed and the metal thin film is simultaneously transferred, and then the cloth and the base film are peeled off. Product manufacturing method.   6. The manufacturing method according to claim 5, wherein the fabric is a knitted fabric having a surface texture of 10 yarns / inch to 80 yarns / inch.   The manufacturing method according to claim 5 or 6, wherein the metal thin film is a metal thin film selected from the group consisting of Sn, Bi, Al, Zn, In, and alloys thereof.   The manufacturing method according to claim 5, wherein the metal thin film has a thickness of 400 to 600 mm.   The cloth is an embroidery cloth embroidered entirely or partially, and the embroidery is a yarn having a thickness of 200 denier to 2000 denier and a yarn density ranging from 10 / inch to 80 / inch. The manufacturing method according to any one of claims 5 to 8, wherein the embroidery cloth is laminated and disposed so that the embroidered surface is in contact with the transfer film.