JP6130479B2 - Decorative film for film insert molding and manufacturing method thereof - Google Patents

Description

  The present invention relates to a decorative film for film insert molding for providing a concavo-convex pattern on the surface of a molded product and a method for producing the same. The present invention relates to a decorative film for film insert molding that does not crack and a method for producing the same.

  Conventionally, in order to decorate the surface of molded products made of resin, such as housings for home appliances and communication equipment, decorating by placing a decorative film in the mold and then filling the mold with resin So-called film insert molding is performed in which the surface of the molded body is covered with a film (see Patent Document 1). However, the decorative film used for this film insert molding is a one in which a colored layer (picture layer) is provided on one side of a base material layer made of a thermoplastic resin, and a binder layer (adhesive layer) is provided as necessary. Since the weld line is concealed with a simple colored pattern and the surface of the molded body is decorated, its decorativeness is limited compared to three-dimensional decoration.

On the other hand, in recent years, surface decoration using fine uneven patterns has also been performed.
However, when the surface of a decorative film made of a thermoplastic resin as described above is provided with a concavo-convex pattern and film insert molding is performed, the concavo-convex pattern is deformed due to the temperature and pressure of the resin poured into the mold, and it is drastic. In this case, since the uneven pattern may be completely crushed, it is extremely difficult to apply the intended uneven pattern with this method.

  As a decorative film in which the uneven pattern is not crushed by the temperature and pressure of the resin poured into the mold, a surface protective layer made of ionizing radiation curable resin is provided on the base material layer, and this surface protective layer and shaping There is a method in which a concavo-convex pattern provided on a mold is disposed so as to face each other, and after the concavo-convex pattern is formed on the surface of the surface protective layer, it is cured by irradiation with ionizing radiation (see Patent Document 2). However, in this method, not only is the operation complicated, but the decorative layer of such a decorative film is cracked or torn when the part of the film is stretched by deep drawing or the like. Therefore, the application is limited and lacks versatility.

JP-A-8-183064 JP 2004-42409 A

  In view of such a situation, the present invention eliminates the problems of the above-described prior art, the concavo-convex pattern is not crushed at the time of molding, and a decorative film for film insert molding that does not crack even when deep drawing is performed and its An object is to provide a manufacturing method.

The present invention was made in order to achieve the above object, and the first feature of the present invention is a resin decorative film for imparting a concavo-convex pattern to the surface of a molded product in film insert molding,
It consists of a shaping layer film provided with a concavo-convex pattern and a protective layer film adhered to the concavo-convex pattern,
The shaping layer film is made of a thermoplastic resin,
The protective layer film is made of a thermoplastic resin containing an ionomer,
10. The shaping layer film and the protective layer film are JIS-Z0237. Adhesive strength measurement 10.4.1 Decorative film for molding film inserts, characterized by being bonded with an adhesive strength of 0.01 to 10 N / 25 mm by a measurement method based on 180 ° peeling adhesive strength to a test plate Is the content.
The second feature of the present invention includes the decorative film for film insert molding described above, wherein the shaping layer film contains polycarbonate .
The third feature of the present invention includes the decorative film for film insert molding as described above, wherein a colored layer and / or a binder layer is further provided on the back side of the shaping layer film provided with the uneven pattern. And
The fourth feature of the present invention is to produce a resin-made decorative film for imparting a concavo-convex pattern on the surface of a molded product in film insert molding.
Forming a shaping layer film having a concavo-convex pattern with the thermoplastic resin A;
It comprises a step of laminating a protective layer film made of a thermoplastic resin B containing an ionomer that fills the uneven pattern on the uneven pattern of the shaping layer,
10. The shaping layer film and the protective layer film are JIS-Z0237. Adhesive strength measurement 10.4.1 For film insert molding, resin A and resin B are selected to have an adhesive strength of 0.01 to 10 N / 25 mm by a measurement method based on 180 ° peeling adhesive strength to a test plate. The method includes a method for producing a decorative film.
A fifth feature of the present invention is the above-described decoration for film insert molding, in which the protective layer film is laminated by melting and extruding the thermoplastic resin B on the concavo-convex pattern of the shaping layer film made of the thermoplastic resin A. The production method of the film is included.
A sixth feature of the present invention is that a film made of a thermoplastic resin B having a melting point lower than that of the thermoplastic resin A is layered on the concavo-convex pattern of the shaping layer film made of the thermoplastic resin A. The production method of the decorative film for film insert molding described above, in which the plastic resin B is melted and the protective layer film is laminated, is included.

  According to the decorative film of the present invention, the concavo-convex pattern of the shaping layer film is closely protected by the protective layer film, both films are weakly bonded, and the protective layer film can be peeled and removed from the shaping layer film after molding. Since it is comprised, there is no possibility that this uneven | corrugated pattern will be crushed at the time of shaping | molding. In addition, when the film is stretched, the concavo-convex pattern is stretched in the same way, and there is no risk of the pattern cracking or unnaturally tearing. It can also be used and is versatile.

  The adhesive force between the resin A constituting the shaping layer film and the resin B constituting the protective layer film is determined according to JIS-Z0237. Adhesive strength measurement 10.4.1 Protective film is inadvertent before film insert molding or during molding by setting it to a range of 0.01 to 50 N / 25 mm by a measurement method based on 180 ° peeling adhesion to a test plate. Further, there is no inconvenience that the protective layer film is torn when the protective layer film is peeled off after molding, or a part of the shaping layer film is peeled off at the same time.

FIG. 1 is a schematic sectional view showing a decorative film for film insert molding of the present invention. FIG. 2 is a schematic cross-sectional view showing how to use the decorative film for film insert molding of the present invention. FIG. 3 is a schematic cross-sectional view showing a method for using the decorative film for film insert molding of the present invention. FIG. 4A is a cross-sectional view showing the outline of a press mold for preforming a decorative film, and FIG. 4B is a cross-sectional view showing the outline of a mold for film insert molding.

The decorative film 1 in the present invention comprises, for example, as shown in FIG. 1, a shaping layer film 2 provided with a concavo-convex pattern 2a and a protective layer film 3 in close contact with the concavo-convex pattern 2a. The protective layer film 3 is weakly bonded.
In the present invention, the weak adhesion means that the laminated shaping layer film 2 and the protective layer film 3 are bonded with an adhesive force that can be easily peeled off with a relatively small force.

  The decorative film 1 of the present invention is a resin decorative film for imparting a concavo-convex pattern on the surface of a molded product in film insert molding, and as shown in FIG. The inserted shaping layer film 2 is joined to the molten resin P injected into the mold. After demolding, as shown in FIG. 3, the protective layer film 3 is peeled and removed from the shaping layer film 2, and the surface of the concavo-convex pattern 2a is exposed, and a molded body decorated with the concavo-convex pattern 2a is obtained.

In this invention, the shaping layer film 2 is a part which decorates the surface of a molded product among the decorative films 1, and the uneven | corrugated pattern 2a is attached | subjected. The material of the shaping layer film 2 is weakly bonded to the protective layer film 3 and is firmly bonded directly to the resin injected into the mold in the film insert molding or via the binder layer (adhesive layer) 5. The thermoplastic resin is not particularly limited as long as it is a thermoplastic resin having sufficient strength and safety as a surface material of a molded body. Specifically, from the viewpoint of strength and safety, polycarbonate (PC), acrylonitrile-butadiene-styrene copolymer (ABS), polymethyl methacrylate (PMMA), polyethylene terephthalate (PET), polybutylene terephthalate (PBT) ), Polyethylene naphthalate (PEN), polystyrene (PS), acrylonitrile-styrene copolymer (AS), methyl methacrylate-styrene copolymer (MS), cyclic polyolefin (COP), cyclic olefin copolymer (COC), Thermoplastic polyurethane (TPU), polyamide (PA), etc. may be used alone or in admixture or lamination of two or more. The adhesiveness with the injected resin and the relationship with the protective layer film 3 will be described later.
The resin may be transparent, translucent, or opaque, and may be colored. However, when the colored layer (design layer) 4 is provided under the shaping layer film, the resin is transparent or translucent.

  In the present invention, the shaping layer film 2 is provided with an uneven pattern 2a. The shape of the concavo-convex pattern 2a is not particularly limited, and any shape such as a line drawing, a relief pattern, or an emboss may be provided. Further, the height (depth) of the concavo-convex pattern is not particularly limited as long as it can be recognized with the naked eye and does not penetrate the shaping layer film 2, and specifically, a range of about 0.1 to 300 μm is exemplified. The

  In the present invention, the protective layer film 3 fills the concave / convex pattern 2a of the shaping layer film 2 and is in close contact with the concave / convex pattern 2a to prevent the concave / convex pattern 2a from being crushed during molding. Later, it is peeled off from the shaping layer film 2. The protective layer film 3 is made of a thermoplastic resin that is weakly bonded to the shaping layer film 2 and has such strength and flexibility that it cannot be broken in the middle when it is peeled off from the shaping layer film 2. If it is, it will not specifically limit, For example, low density polyethylene (LDPE), linear low density polyethylene (LLDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), ethylene-vinyl acetate copolymer (EVA) ), Ethylene-acrylic acid copolymer (EAA), ethylene-ethyl acrylate copolymer (EEA), ethylene-methacrylic acid copolymer (EMAA), ethylene-methacrylic acid copolymer (EMMA), ethylene-methyl Acrylate copolymerization (EMA), ionomer (IO), polypropylene (PP), polymethylpentene (TPX) They include polybutylene (PB), and these can be used alone, or two or more mixed or laminated to. The relationship with the shaping layer film 2 will be described later.

The thickness of the protective layer film 3 is not particularly limited as long as the protective layer film 3 has a thickness that is not easily broken when peeled and removed from the shaping layer film 2, can be appropriately bent, and can be folded back as necessary.
In addition, from the viewpoint that it does not break when it is peeled and removed from the shaping layer film 2, the height difference of the concavo-convex pattern 2 a (the height of the highest part and the lowest part of the concavo-convex pattern is different, depending on the resin used. The thickness of the difference of the depth of 10) is added to the thickness of 10 μm or more. Specifically, when the height difference of the concavo-convex pattern is 50 μm, the thickness is preferably 60 μm or more. When the thickness is less than this thickness, the protective layer film 3 tends to be easily broken when the protective layer film 3 is peeled and removed depending on the resin used, the shape of the concavo-convex pattern, the three-dimensional shape of the molded body, and the like.
In addition, from the viewpoint of bending appropriately when removing the protective layer film 3, although it depends on the resin used, it is generally less than or equal to the thickness of the value obtained by adding 100 μm to the height difference of the uneven pattern, specifically, When the height difference of the uneven pattern is 50 μm, it is preferably 150 μm or less. When this thickness is exceeded, depending on the resin used, the shape of the concavo-convex pattern, the three-dimensional shape of the molded body, and the like, when the protective layer film 3 is peeled and removed, the protective layer film 3 is not sufficiently bent and tends to be difficult to peel off. Arise.

In the present invention, a colored layer (picture layer) 4 and / or a binder layer (adhesive layer) 5 can be provided on the back side of the shaping layer film 2 (the side of the surface joined with the molten resin during molding).
In the present invention, the colored layer (picture layer) 4 is a portion that decorates the surface of the molded product separately or in cooperation with the uneven pattern 2 a applied to the surface of the shaping layer film 2. It is the structure similar to the colored layer (design layer) provided in the conventional decorative film without a pattern.
The ink constituting the colored layer (picture layer) 4 is conventionally used as a material for the colored layer (picture layer), such as colorants, dyes and pigments, and commercially available products such as ISX ink and IPX manufactured by Teikoku Ink Manufacturing Co., Ltd. Ink, INQ ink, FM ink manufactured by Jujo Chemical Co., Ltd. can all be used suitably, and these ink coating methods have also been used to form colored layers (pattern layers), such as screen printing. Etc. can be preferably used.

In the present invention, the binder layer (adhesive layer) 5 is a portion for assisting adhesion between the shaping layer film 2 or the colored layer (picture layer) 4 and the resin injected into the mold, and has no uneven pattern. It is the structure similar to the binder layer (adhesion layer) provided in the conventional decorating film. This binder layer need not be provided when the adhesion between the resin constituting the shaping layer film 2 and the colored layer (picture layer) 4 and the resin P injected into the mold is high.
When the binder layer (adhesive layer) 5 is provided, the material is a resin having high compatibility with both the resin constituting the shaping layer film 2 and the colored layer (pattern layer) 4 and the resin P injected into the mold. However, for example, the colored layer (pattern layer) 4 is not provided, the resin constituting the shaping layer film 2 is polycarbonate, and the resin injected into the mold is acrylonitrile-butadiene. -In the case of a styrene copolymer, examples of the binder layer (adhesive layer) 5 that can be used include IMB-003 (trade name) manufactured by Teikoku Ink Manufacturing Co., Ltd. and IMD binder B-2 (trade name) manufactured by Jujo Chemical Co., Ltd. Can be mentioned.

The present invention is characterized in that the shaping layer film 2 and the protective layer film 3 are weakly bonded. The strength of the adhesive strength is not particularly limited as long as the protective layer film 3 can be easily peeled off from the shaping layer film 2 with a relatively small force, and the tensile strength of the resin used and the protective layer The appropriate adhesive strength varies depending on the thickness of the film 3, but in general, JIS-Z0237. Adhesion strength measurement: 10.4-1 N / 25 mm, more preferably 0.02 to 30 N / 25 mm, particularly preferably 0.05 by a measuring method based on 180 ° peeling adhesion to a test plate. If it is -10N / 25mm, the protective layer film 3 can be appropriately peeled off from the shaping layer film 2. FIG.
If the adhesive strength is less than 0.01 N / 25 mm, the protective layer film 3 may be unexpectedly peeled off from the shaping layer film 2 before or during the film insert molding, and if it exceeds 50 N / 25 mm, the protective layer film 3 is protected. Depending on the thickness of the layer film 3 and the tensile strength of each resin, when the protective layer film 3 is peeled off, the protective layer film 3 is broken and a part of the film is left on the molded product side, or a part of the uneven pattern 2a. May be peeled off together with the protective layer film 3, and the uneven pattern 2a may be crushed or deformed.

Whether or not the adhesion between the shaping layer film 2 and the protective layer film 3 is weak adhesion depends on whether the resin constituting the shaping layer film 2 (hereinafter sometimes referred to as “resin A”) and the protective layer film 3 are used. This is considered to be determined by the compatibility with the resin constituting the resin (hereinafter sometimes referred to as resin B). That is, by suitably selecting the combination of the resin A and the resin B, the adhesion between the shaping layer film 2 and the protective layer film 3 can be weakly bonded.
For example, when polycarbonate is used as the resin A, when polyethylene or ethylene vinyl acetate is used as the resin B, the protective layer film 3 can be easily peeled off from the shaping layer film 2.

  In addition, the thickness of the decorative film 1 of the present invention is preformed (when the decorative film is molded into the same shape as the surface shape of the molded body prior to film insert molding) when placed in the mold. It is preferable that the thickness is easily set, specifically 500 μm or less. When it exceeds 500 μm, it becomes difficult to perform preliminary molding quickly, and workability tends to deteriorate.

Hereinafter, the manufacturing method of the decorative film of this invention is demonstrated.
The present invention comprises a step of producing a shaping layer film from resin A and a step of laminating a protective layer film made of resin B on the shaping layer film, wherein the shaping layer film and the protective layer film are weak. The resin A and the resin B are selected so as to be in an adhesive state. However, since the selection of the resin A and the resin B is as described above, the description is omitted.

  In the present invention, first, the shaping layer film 2 provided with the concavo-convex pattern 2a is manufactured using the resin A. As a method for producing the shaping layer film 2, all methods conventionally used for producing a film having a three-dimensional concavo-convex pattern on one side using a thermoplastic resin as a raw material can be suitably used. For example, in a method in which a resin extruded into a film shape is sandwiched between two metal cooling rolls, a method of engraving a female mold of the concavo-convex pattern 2a on the surface of one of the metal cooling rolls, extrusion into a film shape In a method in which the resin is sandwiched between a metal cooling roll and a rubber roll, a female film having an uneven pattern 2a is formed on the surface of the metal cooling roll, or a female film having an uneven pattern 2a transferred to the rubber roll side. And the like.

  Next, the protective layer film 3 is laminated on the shaping layer film 2. The method for laminating the protective layer film 3 is not particularly limited as long as the concave-convex pattern 2a of the shaping layer film 2 is filled with the resin B and laminated so that the protective layer film 3 is in close contact with the concave-convex pattern 2a. The resin B is melted and extruded onto the concavo-convex pattern 2a of 2 and the so-called extrusion laminating method, or a film made of the resin B having a melting point lower than that of the resin A is superimposed on the concavo-convex pattern 2a of the shaping layer film 2. The so-called thermal laminating method can be used in which the resin A is not melted or softened, and the heat and pressure are applied so that only the resin B is melted and softened.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated further in detail, this invention is not limited only to these Examples.

Example 1
A polycarbonate transparent resin “Panlite L-1225Y (trade name)” manufactured by Teijin Chemicals Limited is selected as the material for the shaping layer film (resin A), and this is extruded into a sheet form from a T-die at a resin temperature of 300 ° C. In the method of narrowing the extruded sheet-like molten resin between a metal cooling roll and a rubber roll, a silk embossed embossing (uneven A shaped layer film provided with a pattern) was produced. The obtained shaping layer film had a thickness of 125 μm and an embossing depth of 45 μm.
On the other hand, a low-density polyethylene resin “Sumikasen CE4009 (trade name)” for extrusion lamination made by Sumitomo Chemical Co., Ltd. was selected as the material for the protective layer film (resin B), and this was selected from the T die at a resin temperature of 280 ° C. Extruded into a sheet shape on the uneven pattern of the shaping layer film, the laminated body of the extruded sheet-like molten resin and the shaping layer film was narrowed between a metal cooling roll and a rubber roll to obtain a laminate. Among the obtained laminates, the thickness of the protective layer film was 100 μm, and the thickness of the entire laminate was 180 μm (125 + 100−45).
The insert molding ink “IPX Screen Ink (trade name)” manufactured by Teikoku Mfg. Co., Ltd. was applied to the surface of the resulting laminate on the shaping layer film side by screen printing and dried with hot air at 80 ° C. for 30 minutes. A colored layer (pattern layer) was provided.
Further, an insert molding binder “IMB-003 Binder (trade name)” manufactured by Teikoku Ink Manufacturing Co., Ltd. was applied on the colored layer (pattern layer) by screen printing, and dried with hot air at 80 ° C. for 30 minutes. A binder layer (adhesive layer) was provided.
As described above, a decorative film for film insert molding having a four-layer structure in which a protective layer film, a shaping layer film, a colored layer (picture layer), and a binder layer (adhesive layer) were laminated in order from the outside was obtained. .

(Example 2)
EVA film obtained by extruding EVA resin “Evaflex P1007” manufactured by Mitsui DuPont Polychemical Co., Ltd. at a resin temperature of 130 ° C. to a thickness of 75 μm as a method of laminating the protective layer film on the uneven pattern of the shaping layer film. A film having a four-layer structure, in the same manner as in Example 1, except that the concavo-convex pattern of the shaping layer film was filled by thermocompression bonding at 100 ° C. using a thermal laminator. A decorative film for insert molding was obtained.

(Comparative Example 1)
As a method of laminating the protective layer film on the concavo-convex pattern on the shaping layer film side, a protective adhesive film “SANITECT LP54M (manufactured by Sanei Kaken Co., Ltd.) in which a 7 μm adhesive layer is provided on a 50 μm thick polyethylene film. Name) ”was affixed on the concavo-convex pattern in the same manner as in Example 1 to obtain a decorative film for film insert molding having a four-layer structure.
In addition, in this decorative film for film insert molding, the protective layer film is bonded only at the upper end portion of the convex portion of the concavo-convex pattern, and the concavo-convex pattern is not filled.

(Measurement of adhesive strength)
Test pieces having a width of 25 mm and a length of 150 mm were obtained from the decorative films of Examples 1 and 2 and Comparative Example 1 obtained as described above. About 25 mm from one end of this test piece is peeled off by hand, the protective layer film is folded back at 180 ° so that the back surface is overlapped, and the shaping layer film is folded on one chuck of the tensile tester, and the protective layer film is folded on the other chuck The layer film was fixed.
From this state, the operation of the tensile tester was started at 5 mm / s, and the average value of the measured adhesive force from 5 seconds to 15 seconds after the start of the tensile test was taken as the adhesive strength of each decorative film.
The measured values were 0.10 N / 25 mm (Example 1), 0.17 N / 25 mm (Example 2), and 0.18 N / 25 mm (Comparative Example 1), respectively.

(Preliminary molding)
After pre-heating the decorative films of Examples 1 and 2 and Comparative Example 1 to 70 ° C., as shown in FIG. 4 (a), the shape of the convex lens having a radius of 90 mm and a protrusion height of 30 mm is shown. Were pre-molded using a press die.

(Film insert molding)
The pre-molded decorative film is placed in a convex lens-shaped mold having a radius of 90 mm and a protruding height of 30 mm as shown in FIG. 4 (b), and then polycarbonate / acrylonitrile-butadiene- The styrene copolymer mixed resin is injected into the mold, the injected resin and the decorative film are integrated, and after demolding, the protective layer film is peeled off from the shaping layer film on the surface of the molded product and decorated. Got the finished product.

(Evaluation)
In the molded product using the decorative film of Examples 1 and 2, the uneven pattern of the shaping layer film was retained as it was without any deformation, and was decorated as intended. Comparative Example 1 In the molded product using the decorative film, the irregular pattern of the shaping layer film was crushed and the intended appearance could not be obtained.

  As described above, the decorative film for film insert molding according to the present invention comprises a shaping layer film provided with a concavo-convex pattern and a protective layer film in close contact with the concavo-convex pattern, the shaping layer film and the protective layer film. Since it is weakly bonded, the concavo-convex pattern is protected by the protective layer at the time of molding, so it is not crushed, and the protective layer can be easily peeled and removed after molding, and the concavo-convex pattern of the shaping layer film is It is decorated as it is without deformation. Moreover, since cracking does not occur even when deep drawing is performed, it is useful as a decorative film for film inserts.

DESCRIPTION OF SYMBOLS 1 Decorative film for film insert molding 2 Shaping layer film 2a Uneven pattern 3 Protective layer film 4 Colored layer (pattern layer)
5 Binder layer (adhesive layer)
M Mold P Resin injected into the mold

Claims (6)

A resin decorative film for imparting a concavo-convex pattern on the surface of a molded product in film insert molding,
It consists of a shaping layer film provided with a concavo-convex pattern and a protective layer film adhered to the concavo-convex pattern,
The shaping layer film is made of a thermoplastic resin,
The protective layer film is made of a thermoplastic resin containing an ionomer,
10. The shaping layer film and the protective layer film are JIS-Z0237. Adhesive strength measurement 10.4.1 Decorative film for molding film inserts, characterized by being bonded with an adhesive strength of 0.01 to 10 N / 25 mm by a measurement method based on 180 ° peeling adhesive strength to a test plate . The decorative film for film insert molding according to claim 1, wherein the shaping layer film contains polycarbonate . On the back side of the vehicle-layer film uneven pattern is provided, further, the decorative film for film insert molding according to claim 1 or 2, characterized in that the colored layer and / or a binder layer is provided. In producing a decorative film made of resin for imparting a concavo-convex pattern on the surface of a molded product in film insert molding,
Forming a shaping layer film having a concavo-convex pattern with the thermoplastic resin A;
It comprises a step of laminating a protective layer film made of a thermoplastic resin B containing an ionomer that fills the uneven pattern on the uneven pattern of the shaping layer,
10. The shaping layer film and the protective layer film are JIS-Z0237. Adhesive force measurement Resin A and Resin B are selected so as to have an adhesive force of 0.01 to 10 N / 25 mm by a measurement method based on the 180 ° peel adhesive strength with respect to 10.4.1 test plate. A method for producing a decorative film for film insert molding. The decorative film for film insert molding according to claim 4 , wherein the protective layer film is laminated by melting and extruding the thermoplastic resin B on the concavo-convex pattern of the shaping layer film made of the thermoplastic resin A. Manufacturing method. A film made of thermoplastic resin B having a melting point lower than that of thermoplastic resin A is layered on the uneven pattern of the shaping layer film made of thermoplastic resin A, and the thermoplastic resin B is melted by thermal lamination to protect the layer. The method for producing a decorative film for film insert molding according to claim 4 , wherein films are laminated.

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