JPH07256671A - Molding synthetic resin sheet and membrane press molding method - Google Patents

Abstract

PURPOSE:To prevent the damage of a high glossiness of a product in a membrane press molding method utilizing a transfer foil method and to provide the synthetic resin decorative sheet used in said method. CONSTITUTION:A transfer sheet obtained by successively providing at least a release layer 3 and an adhesive layer 5 on the release surface of a releasable sheet 2 is laminated to the surface of a synthetic resin base material sheet 6 and a masking film 1 is provided on the surface of the releasable sheet 2 simultaneously with lamination or after lamination to obtain a synthetic resin sheet for membrane press molding.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a membrane press molding method such as vacuum press molding or pressure air press molding of plastics, and a synthetic resin sheet for molding used for carrying out the molding method, and particularly to high gloss and matteness. The present invention relates to a membrane press molding method having properties such as stain resistance, scratch resistance, antistatic property, and antibacterial property, and a synthetic resin decorative sheet used in the method.

[0002]

2. Description of the Related Art Conventionally, the surface property of a polyester film used as a peelable sheet is used as a technique for imparting excellent glossiness or matte appearance to a surface of a synthetic resin substrate sheet without coating. The transfer foil method is known. In the membrane press molding method using this transfer foil method, after applying high gloss by the transfer foil, the peelable sheet used for the transfer foil is peeled off, and then a polyolefin-based masking film is used before and after the membrane press molding. It is generally used on the surface of the transfer foil for the purpose of preventing scratches and stains.

[0003]

However, in the membrane press molding method utilizing the transfer foil method, if the release sheet used is peeled off, the high glossiness after the membrane press molding may be impaired. In particular, in the release layer or protective layer of the transfer foil, wax fine powder for the purpose of imparting slipperiness, conductive powder for the purpose of imparting antistatic properties, or inorganic fine powder antibacterial agent for the purpose of imparting antibacterial properties, etc. This has been a particular problem when the insoluble inorganic or organic fine powder is substantially uniformly contained or provided in a layered form. Further, when the release sheet of the transfer foil is subjected to membrane press molding without being peeled off, a part of the release sheet is easily caused by a slight scratch or a streak generated on the surface of the release sheet during the manufacturing process of the membrane press. It will be torn and the part of the product corresponding to that part will have a particularly poor appearance. Further, when the peelable sheet is peeled off after the membrane press molding, there is a problem that the peelable sheet is easily torn and the workability is poor.

In the membrane press molding method using the above-mentioned conventional transfer foil method, the reason why the high glossiness after the membrane press molding is impaired is that the film is curved along the uneven surface of the molding substrate during the membrane press molding. The part of the product stretches more unevenly than other parts, and when the fine powder described above is contained, it is found that the uneven spread is enlarged due to the fine powder, This completes the present invention.

That is, the present invention provides a membrane press molding method using the transfer foil method, which does not impair the high glossiness of the product, and a synthetic resin decorative sheet used in the method. It is an object.

[0006]

In order to solve the above-mentioned problems, the present inventor sequentially provided an adhesive layer (providing a protective layer and a conductive layer, if necessary) after applying a release layer to a release sheet. A masking film was further provided on the peelable sheet of the synthetic resin substrate sheet laminated with the transfer sheet. That is, the invention of claim 1 of the present application, as shown in FIG.
A synthetic resin substrate sheet 6 is provided on the adhesive layer side of a transfer sheet in which a release layer 3 and an adhesive layer 5 are sequentially provided, and a masking film 1 is provided on the surface of the release sheet 2. It is a synthetic resin sheet for molding. Further, as shown in FIG. 1, the invention of the present application is a synthetic resin substrate comprising a transfer sheet in which at least a release layer 3, a protective layer 4 and an adhesive layer 5 are sequentially provided on a release side surface of a release sheet 2. A synthetic resin sheet for membrane press molding, which is laminated on the surface of a sheet 6, and a masking film 1 is provided on the surface of the releasable sheet 2 simultaneously with or after the lamination. Further, the invention of claim 3 is characterized in that at least one of layers constituting the transfer sheet or a layer between the layers is provided with a layer containing fine powder insoluble in the coating material substantially uniformly. It is a resin sheet. Further, an embodiment of the invention of the present application is that a conductive powder, an inorganic fine powder antibacterial agent, and a wax fine powder are provided on at least any one of layers constituting the transfer sheet or on the surface, back surface or interlayer of at least any one of the layers. Synthetic resin for membrane press molding, characterized in that insoluble fine powder is substantially uniformly or partially contained in a coating material such as or the like, or a continuous or intermittent fine powder layer is provided wholly or partially. It is a sheet, and in FIG.
An example is shown in which the conductive layer 7 is provided between the adhesive layer 5 and the adhesive layer 5.

In the present invention, the peelable sheet is not particularly limited, but a biaxially stretched polyester film is preferable from the final finished state of the product such as surface property, smoothness, hardness and heat processability, and the thickness is Approximately 4 to approximately 50 μ, preferably approximately 5 to approximately 25 μ. If the thickness is about 4 μm or less, it is difficult to process the transfer foil, and if it is about 50 μm or more, the molding process is difficult. Further, the surface property of the peeling side surface of the peelable sheet may have an uneven pattern such as grain, emboss or hairline by mechanical processing such as sand plast, hot roll press processing, printing processing or fine particle kneading method. . In this case, the product is given a predetermined matte appearance.

In the present invention, the synthetic resin substrate sheet is made of a thermoplastic resin such as vinyl chloride resin, polyolefin resin, polystyrene resin, etc., which has moldability at about 70 ° C to 120 ° C.

In the present invention, the masking film is provided with a heat-sensitive or pressure-sensitive adhesive such as acrylic resin, polyester resin, polystyrene thermoplastic elastomer, vinyl chloride vinyl acetate resin, EVA resin or EEA resin by coating or coextrusion. A resin film such as a polyolefin-based or vinyl chloride-based resin having a thickness of about 20 to about 200 μ, preferably about 20 to about 100 μ is suitable. A film having a thickness of about 20 μ or less has a production problem, and a film having a thickness of about 200 μ or more causes a problem in molding. Further, the masking sheet preferably has a tensile elongation of at least 100% according to the JIS Z 1702 tensile test.

In the present invention, the release layer is preferably a resin having an adhesive property with the polyester film, for example, an acrylic resin. At this time, the purpose is to add fine particle wax and various functions for the purpose of preventing scratches. Various additives can be used. Further, for the purpose of further stabilizing the peeling property, an acrylic resin added with a silicon-based additive or copolymerized with silicon can be used. Furthermore, in addition to the peeling layer, a more complete peeling property can be obtained. For this purpose, the polyester film side may be coated with a thermosetting resin such as an acrylic melamine-based resin or an epoxy melamine-based resin or an ultraviolet-curable resin for release treatment. In the present invention, as the protective layer, acrylic, urethane, epoxy,
A silicone resin or the like can be used, and can be selected according to the performance required for the protective layer, such as weather resistance, solvent resistance, scratch resistance, and the like. Further, it is preferable that the resin is selected from resins having a room temperature curability, a thermosetting property, an ionizing radiation curability property and the like in view of production or required performance. In the present invention, as the adhesive layer, an acrylic resin, a chlorinated polyolefin resin, or the like resin that can be generally used as an adhesive, or a mixture of two or more thereof can be used.

In the present invention, in the layer structure of the peeling layer and the adhesive layer, a protective layer may be provided or the adhesive layer may also serve as the protective layer depending on the purpose. In the invention of claim 4, the protective layer has a heat-bonding function and the protective layer and the adhesive layer are integrated, so that the adhesive layer also serves as the protective layer. Further, a printing layer for the purpose of decoration can be provided on any of the peeling layer, the protective layer and the adhesive layer. In the present invention, the inorganic fine powder antibacterial agent is used in any one of the peeling layer, the protective layer and the adhesive layer, or in the interlayer, but it is preferably added to the peeling layer and / or the protective layer.

In the present invention, any conductive powder used in any one of the peeling layer, the protective layer and the adhesive layer or between the layers may be used, but it is necessary to use them properly depending on the requirements.
For example, conductive tin oxide is preferable when transparency is required, fine barium sulfate powder coated with conductive tin oxide is required when colorlessness is required, and carbon black is preferable when blackness is required. The conductive paint may be applied by a normal gravure coating method, a reverse roll method, or the like, but a line spacing within a range satisfying the antistatic ability (for example, within 4 mm).
It may be partially printed in a stripe pattern or a grid pattern.

Next, the membrane press molding method of the present invention is carried out using the synthetic resin sheet for membrane press molding described above. That is, claim 7 of the present application
According to the invention, a transfer sheet having at least a release layer and an adhesive layer sequentially provided on the release side of a release sheet is laminated on the surface of a synthetic resin substrate sheet, and the release is performed simultaneously with or after the lamination. To produce a molding synthetic resin sheet by providing a masking film on the surface of the flexible sheet, preheat the molding synthetic resin sheet, and membrane press mold the molding synthetic resin sheet along the uneven surface of the molding substrate, Thereafter, the masking film is peeled off together with the peelable sheet, which is a membrane press molding method.

In the present invention, the transfer method may be an ordinary laminating method such as hot pressing or hot roll pressing, but extrusion laminating using heat during extrusion is preferable. Also, embossing can be performed simultaneously with or after the lamination. Further, at this time, a PVC film having a pattern printed in advance on the extruded sheet may be laminated on the surface of the synthetic resin substrate sheet, and then the transfer sheet may be provided on the surface to obtain a decorative sheet having a pattern.

According to a sixth aspect of the present invention, as shown in FIG. 3, the synthetic resin base sheet 6 has a layer 6-, such as a print layer, on at least one of the front surface and the back surface of the base sheet main body 6-2. 1 is a synthetic resin sheet for membrane press molding having a composite structure in which the printed layer 6-1 such as a pattern is provided on the surface of the base sheet main body 6-2 in the embodiment of FIG. When the base sheet main body 6-2 is transparent,
A layer such as a print may be provided on the back surface.

[0016]

In each of the above inventions, since the peelable sheet is uniformly protected by the masking film when the synthetic resin sheet for membrane press molding is membrane-press molded along the uneven surface of the molding substrate,
The peelable sheet will not be damaged. As a result, the peelable sheet uniformly protects the uneven surface and the curved surface of the corner of the product at the time of molding, and evenly curves, and the uneven surface of the product and a part of the curved surface of the corner are unevenly stretched or finely divided. It won't crack. Therefore,
By using a synthetic resin sheet for membrane press molding having a polyester film and a masking film as a peelable sheet according to the present invention, vacuum molding, pressurized air molding, or membrane molding using a film-like elastic body filled with air or a liquid medium, etc. After that, the polyester film and the masking film can be easily peeled off to obtain a molded product having excellent surface properties and functions.

[0017]

EXAMPLES The present invention as described above will be described by way of Examples and Comparative Examples.
Further details will be described. In Example-2 and Comparative Example-2, an acrylic resin was used as a binder, and conductive tin oxide T-1 was used.
(MITSUBISHI MATERIALS) using conductive paint TEPC-1 (MITSUBISHI MATERIALS) having a conductive powder concentration of 60% in the solid content of 16 seconds by Iwata Cup NK-II,
In Example-3 and Comparative Example-3, conductive tin oxide T-1 was replaced with conductive tin oxide-coated barium sulfate (Mitsui Kinzoku Pastran Type IV), and the conductive powder concentration in the solid content was 70%. In Example-4 and Comparative Example-4, conductive carbon (Lion Ketjen Black BC) having a solid content of conductive powder of 10% was used.

Example 1 A polyester film as a peelable sheet having a thickness of 12 μm, which had been previously subjected to a release treatment with an acrylic melamine resin, was used as a release layer to form a finely divided polyethylene wax [S-381 (S-381 ( Sanyo Trading)] and fine silver-based inorganic antibacterial agent (trade name: Novalon AG300 Toa Gosei Kagaku)
After applying an acrylic paint in which 2% is dispersed in a solid fraction, a thermosetting acrylic paint having a thickness of 2μ is used as a protective layer, and an acrylic adhesive having a thickness of 1μ is subsequently used as an adhesive layer. A coated thermal transfer sheet is obtained, and a PVC sheet (having a thickness of 0.7
(mm)), and then laminated on the outside of the polyester film on the PVC sheet with a pressure-sensitive masking film (San-A Chemical Co., Ltd. PAC-S4-60) obtained by coextruding a polyolefin resin and an EVA resin. PV as a synthetic resin sheet for membrane press molding having a film and a masking film
A C sheet was obtained. Next, after applying a urethane-based primer on the back surface of the PVC sheet, and preheating to 80 ° C. with the polyester film and the masking film still present, a thickness of 2 in which the urethane-based primer was applied in advance.
4 mm MDF (medium fiber board specified in JIS A5906 with a semicircular engraving with a radius of 15 mm in the center)
Membrane molding was performed on a substrate under vacuum and pressure, and then the polyester film and the masking film were peeled off to obtain a furniture panel having scratch resistance, antibacterial properties, and at the same time excellent surface properties such as gloss. The performance is shown in the table of FIG. The structure is shown in FIG.

Example-2 A polyester film as a releasable sheet having a thickness of 12 μm similar to that of Example-1 was coated with finely powdered polyester wax [S-381 (Sanyo Trading Co., Ltd.)] so that the release layer had a thickness of 0.5 μm. After applying an acrylic paint containing 2% by solid content, use acrylic resin as a binder and conductive tin oxide (Mitsubishi Materials) at a conductive powder concentration of 60% in the solid content.
After the conductive paint TEPC-1 was applied, a thermosetting acrylic paint having a thickness of 2 μm was applied as a protective layer, and an acrylic adhesive having a thickness of 1 μm was subsequently applied as an adhesive layer to obtain a thermal transfer sheet. Pressure-sensitive masking obtained by heat-transferring onto a PVC sheet (thickness 0.7 mm) as a synthetic resin base sheet immediately after die extrusion, and then coextruding a polyolefin resin and EVA resin outside the polyester film on the PVC sheet. Film (San-A Chemical / PAC
-S4-60) was laminated to obtain a PVC sheet as a synthetic resin sheet for membrane press molding having a polyester film and a masking film on the outside of the surface having an antistatic function. Next, the PVC sheet was preheated to 80 ° C. while the polyester film and the masking film were still attached, and thereafter, the MDF (described in Example 1) substrate having a thickness of 24 mm was subjected to membrane molding under vacuum and air pressure, and then, The polyester film and the masking film were peeled off to obtain a furniture panel having antistatic properties and excellent surface properties such as gloss. The performance is shown in the table of FIG. The structure is shown in FIG.

Example-3 The same as Example-2 except that barium sulfate coated with conductive tin oxide was used instead of conductive tin oxide. The performance is shown in the table of FIG. Example-4 The same as Example-2 except that conductive carbon was used instead of conductive tin oxide.

Comparative Example-1 A polyester film having a thickness of 12 μm similar to that of Example-1 and a finely powdered polyethylene wax [S-381 (Sanyo Trading Co., Ltd.)] and a silver-based inorganic antibacterial agent were used so that the release layer had a thickness of 0.5 μm. Fine powder (trade name: Novalon AG300 Toa Gosei Kagaku)
After applying an acrylic paint containing 2% in terms of solid fraction, a thermosetting acrylic paint having a thickness of 2 μm is applied as a protective layer, and an acrylic adhesive having a thickness of 1 μm is subsequently applied as an adhesive layer. PV that was obtained immediately after T-die extrusion
After thermal transfer to a C sheet (thickness 0.7 mm), the P
80 with polyester film on VC sheet
After preheating to ℃, vacuum on a MDF substrate with a thickness of 24 mm.
I tried to mold the membrane under pressure and tried to peel the release sheet after molding, but it broke everywhere and the work was difficult. Also,
The release sheet was torn at the corner of the molded product, and the appearance of that part was poor. Comparative Example-2 A finely powdered polyethylene wax [S-381 (Sanyo Trading Co., Ltd.)] was added to a polyester film having a thickness of 12 [mu] similar to that of Example-1 so as to have a thickness of 0.5 [mu] as a release layer in a solid fraction of 2%. Conductive paint TEPC with acrylic resin as binder and conductive tin oxide (Mitsubishi Marial) with conductive powder concentration of 60% in solid content after applying acrylic paint containing
-1 was applied, then a thermosetting acrylic paint having a thickness of 2 μm was applied as a protective layer, and an acrylic adhesive having a thickness of 1 μm was subsequently applied as an adhesive layer to obtain a thermal transfer sheet. Heat transfer to a PVC sheet (thickness 0.7 mm),
A PVC sheet having an antistatic function was obtained. Then the PV
After preheating the C sheet with the polyester film attached to 80 ° C., the film on the MDF substrate with a thickness of 24 mm was membrane-molded under vacuum and air pressure, and then the polyester film was peeled off, but it broke everywhere. , Work was difficult. Further, the release sheet was torn at the corner of the molded product, and the appearance of the part was poor. Comparative Example-3 The same as Example-2 except that conductive tin oxide-coated barium sulfate (solid content ratio 70%) was used instead of conductive tin oxide (solid content ratio 60%). Comparative Example-4 The same as Example-2 except that conductive carbon (solid content ratio 10%) was used instead of conductive tin oxide (solid content ratio 60%).

[0022]

As described above, according to the present invention,
In membrane press molding that uses a transfer sheet to give a good appearance to the product, by using a synthetic resin sheet for molding that has a masking film on the surface of the peelable sheet The masking film can be peeled off to obtain a molded product having excellent surface properties and functions. Also,
Since the peelable sheet is not damaged during membrane formation, workability when peeling the peelable sheet from the surface of the product is improved.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing the structure of a molding synthetic resin sheet according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a structure of a molding synthetic resin sheet according to another embodiment of the present invention.

FIG. 3 is a cross-sectional view showing the structure of a molding synthetic resin sheet according to still another embodiment of the present invention.

FIG. 4 is a table for explaining the operation of the example of the present invention and the comparative example.

[Explanation of symbols]

1 masking film, 2 release sheet, 3 release layer, 4 protective layer, 5 adhesive layer, 6 synthetic resin base sheet,
7 Conductive layer

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location B32B 27/36 7421-4F // B29K 105: 06

Claims (7)

[Claims] 1. A synthetic resin substrate sheet is provided on a surface of the transfer sheet, which is formed by sequentially providing a release layer and an adhesive layer on the release side of the release sheet, on the side of the adhesive layer, and the surface of the release sheet. A synthetic resin sheet for molding, which is provided with a masking film. 2. The molding synthetic resin sheet according to claim 1, wherein the transfer sheet is provided with at least a release layer, a protective layer and an adhesive layer in that order on the release side of the release sheet. 3. The layer according to claim 1 or 2, wherein a layer containing fine powder insoluble in the coating material is substantially uniformly provided between at least one layer or layers of the layers constituting the transfer sheet. Molding synthetic resin sheet. 4. Of the layers constituting the transfer sheet,
The synthetic resin sheet for molding according to claim 2 or 3, wherein the adhesive layer also serves as a protective layer. 5. The peelable sheet is made of polyester resin, and the masking film is provided with a heat-sensitive or pressure-sensitive adhesive layer on the back surface of the polyolefin resin or vinyl chloride resin layer. 2, 3 or 4
The described synthetic resin sheet for molding. 6. The molding composition according to claim 1, wherein the synthetic resin base sheet has a composite structure in which a base sheet is mainly provided with a layer such as a print layer. Resin sheet. 7. A transfer sheet comprising at least a release layer and an adhesive layer sequentially provided on the release side surface of the release sheet,
A synthetic resin sheet for lamination was laminated on the surface of a synthetic resin substrate sheet, and at the same time as or after the lamination, a masking film was provided on the surface of the peelable sheet to produce a synthetic resin sheet for molding, and the synthetic resin sheet for molding was preheated. After that, the synthetic resin sheet for molding is subjected to membrane press molding along the uneven surface of the molding substrate, and then the masking film is peeled together with the peelable sheet, and the membrane press molding method is characterized.