JP3217175B2 - Manufacturing method of sheet for coating - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the possibility of human being touching molded articles such as interiors of automobiles, housings such as office automation (OA) equipment and home appliances, stationery, sanitary goods, daily necessities, and interior materials of building materials. The present invention relates to a method for producing a covering sheet capable of imparting a good contact feeling to a molded product by covering a site.

[0002]

2. Description of the Related Art In order to impart a suede feeling (soft touch feeling) to the surface of a plastic molded product or a metal molded product, a suede-like (soft touch) paint has been generally used. For example, JP-A-63-199776 discloses that a nylon powder and a coloring agent or a colored nylon powder are used.
A coating material dispersed in a resin liquid containing a coating film forming resin having an elongation of 60 to 700% has been proposed.

However, Japanese Patent Application Laid-Open No. 63-199776
When coating with a paint as disclosed in Japanese Unexamined Patent Publication, it is necessary to adjust the viscosity and concentration of the paint, which complicates the work. In addition, a paint using an organic solvent requires a booth for drying the solvent, and further causes pollution of the working environment and safety and health problems. In order to solve these problems, for example, JP-A-2-41243 discloses a matte paint in which a bead pigment is added to a vehicle of an ionizing radiation-curable resin on a base film having good moldability and cured. Suede-like sheets have been proposed as an alternative to paint. An apparatus for decorating a sheet at the time of injection molding is proposed in, for example, Japanese Patent Application Laid-Open No. 59-202830.

[0004]

However, Japanese Patent Laid-Open No. 2-4 / 1990
The sheet described in No. 1243 was inferior in the spreadability of the entire sheet because the coating film of the sheet was made of a resin cross-linked by an electron beam. Therefore, this sheet and
When an attempt is made to obtain a molded product having a soft touch feeling on the surface using the apparatus proposed in Japanese Patent Application Laid-Open No. 59-202830, the following problems arise.

[0005] That is, if the sheet is to be adhered to the surface of the adherend having irregularities or a curved surface, the spreadability of the sheet is poor, and the sheet may be torn. Was difficult to impart. An object of the present invention is to solve the above problems and to provide a manufacturing method capable of easily manufacturing a soft touch (suede-like) coating sheet capable of forming a coating having a soft touch feeling.

[0006]

Means for Solving the Problems A method for producing a coating sheet according to the present invention is intended to achieve such an object.
A sheet-like laminate obtained by co-extruding a composition to be a soft touch layer containing a thermoplastic elastomer and elastic fine particles as main components and a thermoplastic resin to be a base layer was stretched to obtain a soft touch sheet. Thereafter, a foam layer is laminated on the substrate layer side of the soft touch sheet.

The details are as follows. The thermoplastic elastomer resin used for the soft touch layer (surface layer) of the coating sheet obtained in the present invention is a polymer that has rubber elasticity at normal temperature and is plasticized at high temperature and can be subjected to various molding processes. The materials are polystyrene, polyurethane, polyolefin, polyester, polyvinyl chloride, polyamide, ionomer, natural rubber, fluorine, 1,2 polybutadiene, trans 1,4 polyisoprene. And so on.

In general, these thermoplastic elastomers often share a rubber component (soft segment) having entropy elasticity in the molecule and a molecular constraint component (hard segment) for preventing plastic deformation.
In some cases, it has a crosslinked structure within the moldable range, but does not have a wide-range three-dimensional stitch structure. The hardness of these thermoplastic elastomers varies depending on the feel to be obtained and the hardness of the elastic fine particles (elastic beads are frequently used). Generally, the hardness of JIS K6301 is in the range of 20 to 98. Is preferred.

As the thermoplastic elastomer, for example, in the case of a polyurethane elastomer, there is a block copolymer having polyurethane as a hard segment and polyether, polyester, polycarbonate or the like as a soft segment. In the case of polystyrene, there are block copolymers having polystyrene as a hard segment and polybutadiene, polyisoprene, and polyethylene-polybutylene as a soft segment, and those obtained by further adding hydrogenation or functional groups thereto.

In the case of polyolefins, those having polypropylene as a hard segment and having ethylene as a soft segment, those having a small amount of a diene component together with ethylene (EPM (ethylene-propylene-methylene bond), EPDM (ethylene- Propylene-diene methylene bond), collectively referred to as EPR (ethylene-
Propylene rubber)), those obtained by blending them, those partially crosslinked by further adding an organic peroxide thereto, and those modified with derivatives of unsaturated hydroxy monomers and unsaturated carboxylic acids. And butyl rubber-grafted polyethylene.

In the case of the polyester type, there is a copolymer having polyester as a hard segment and polyether as a soft segment. In the case of the polyvinyl chloride type, a method obtained by extremely increasing the degree of polymerization of polyvinyl chloride, a method of introducing a three-dimensional crosslinked structure into a part of polyvinyl chloride, a method of introducing an ionic crosslinked structure, and the like are used. is there.

[0012] Among the polyamides, there are polyamides using polyamide as a hard segment and polyether as a soft segment. The type of the thermoplastic elastomer is selected in consideration of the performance desired as a soft touch sheet. For example, when scratch resistance and wear resistance are required, a urethane-based thermoplastic elastomer is preferably used.

The above-mentioned elastic fine particles have the property of recovering elasticity when they are opened after being pressed until their shape is deformed. For example, polyurethane, acrylic-urethane copolymer, polystyrene, styrene-isoprene copolymer Examples thereof include those made of a polymer and the like, and those that do not melt under the extrusion conditions of the thermoplastic elastomer are used. The reason is that when the elastic fine particles are melted and integrated with the thermoplastic elastomer when they are mixed with the thermoplastic elastomer and extruded into a sheet from an extruder, it is difficult to form a good soft touch layer even if the elastic particles are stretched thereafter. This is because

The elastic fine particles having a maximum particle size distribution in the range of 1 to 50 μm are preferably 20 to 200 parts, more preferably 20 to 200 parts by weight per 100 parts by weight of the thermoplastic elastomer resin. Is preferably added in an amount of 50 to 150 parts. That is, if the particle size is less than 1 μm, a sufficient soft touch feeling cannot be obtained on the obtained sheet, and depending on the thickness of the sheet, if the particle size exceeds 50 μm, the sheet is spread or stretched to stretch the sheet. When elongated, cracks tend to form on the surface. On the other hand, if the addition amount is less than 20 parts, sufficient unevenness cannot be obtained and the soft touch feeling is low.
If the amount is more than 0, when the sheet is stretched by stretching or stretching, a crack is easily generated on the surface thereof.

The number of the elastic fine particles is not limited to one type, but may be 2
More than one species may be used in combination. Also, when using a flexible thermoplastic elastomer or when a slightly hard feel is acceptable,
For example, crosslinked polymethyl methacrylate or hard fine particles made of an inorganic material may be used. On the other hand, as the resin constituting the base layer, for example, the above-mentioned thermoplastic elastomer,
Polystyrene, acrylic polymer, polycarbonate, polyvinyl chloride, polyethylene, polypropylene,
ABS (acrylonitrile-butadiene-styrene copolymer), modified polyphenylene oxide, polyphenylene sulfide, polyetherimide, polyetheretherketone, ionomer, and the like. Thermoplastic elastomer is used to provide a softer soft touch feeling. It is preferable to employ a foam made of a synthetic resin.

Examples of the material constituting the foam layer include polyolefin resins such as polypropylene and polyethylene; polystyrene resins such as polystyrene and styrene-maleic anhydride copolymer; polyurethane resins; polyvinyl chloride resins; Foamable resin materials such as various thermoplastic elastomer resins are exemplified. In addition, the expansion ratio of these foams is preferably about 5 to 50 times, particularly preferably about 20 to 50 times, in order to exhibit a soft touch feeling.

[0017] Coextrusion molding refers to a method in which two or more extruders are used, and each extruded resin is merged into one to produce a product having a multilayer structure. The joining method by co-extrusion is roughly classified into a field block method, a multi-manifold method, and a multi-throttle die method. The field block method is a method in which a special block attached just before entering a die joins together, and is also called a black box method. In the multi-manifold method, the number of manifolds in the die is equal to the number of layers. The multi-throttle die method is a method in which the flows are separated in the die and bonded immediately after leaving the die.

Although any of these methods can produce the sheet-like laminate of the present invention, a multi-manifold method is preferable in order to improve the thickness accuracy of each layer and improve the adhesion of each layer. The thermoplastic elastomer and the elastic fine particles constituting the soft touch layer are mixed, then melt-kneaded using a twin-screw extruder, extruded, and co-extruded with a resin serving as a base layer extruded from another extruder. Molding or kneading the thermoplastic elastomer and elastic fine particles in advance and pelletizing,
These pellets can be extruded with a common extruder and co-extruded with a resin to be a substrate layer extruded from another extruder.

When the thermoplastic elastomer and the elastic fine particles are previously kneaded and pelletized, the thermoplastic elastomer and the elastic fine particles can be mixed with a Banbury mixer or the like. Extrusion temperature conditions are, for example, 150 to 200 ° C. in the case of a composition for a soft touch layer using a thermoplastic urethane elastomer.

In the method for producing a coating sheet of the present invention, the elongation after co-extruding the above composition into a sheet from an extruder may, of course, be carried out in a solid state of the sheet-like laminate. In this case, it is generally referred to as stretching. However, the present invention is not limited to this case, and may be performed in a semi-solid state immediately after extrusion as long as the sheet-like form is substantially maintained.

Specifically, the composition may be stretched by a take-up roll immediately after co-extrusion of the composition from an extruder, or may be stretched after sufficiently cooling and shaping the sheet so that it can be wound up. Good. In the case of stretching, usually, after the temperature of the sheet becomes equal to or lower than the softening temperature of the used thermoplastic elastomer, the cooled roll is brought into contact with the sheet, and is further taken up by a take-up roll rotating at a higher speed than the resin discharge speed. Done. When a cooled rubber roll or the like having a roughened surface is used, the temperature may be around the softening temperature.
Further, a tenter stretching method or the like may be employed.

The elongation ratio varies depending on the compatibility between the thermoplastic elastomer and the elastic fine particles to be used, but is preferably at least 1.2 times, more preferably at least 2 times. By being stretched in this way, fine irregularities are formed on the surface of the obtained soft touch sheet, and a soft touch feeling is exhibited. Further, the soft touch sheet thus obtained is annealed as needed.

As a method of laminating the soft touch sheet obtained by co-extrusion as described above and a synthetic resin foam to be a foam layer, for example,
There is a method (extrusion lamination) of laminating a mixture in a molten state on the substrate layer side of a soft touch sheet. In the above co-extrusion, if the adhesion between the soft touch layer and the base material layer is poor, an adhesive layer may be provided between both layers by co-extrusion (three-layer extrusion). When the adhesion between the base material layer and the foam layer is poor, the surface of the foam layer (the surface on the base material layer side)
A primer layer or an adhesive layer may be provided in advance.

As a material constituting the primer layer, for example, when a foam made of a polyurethane-based thermoplastic elastomer is laminated on a polyolefin-based base layer, a chlorinated polyolefin layer or an acid-modified SEBS is used.
(Styrene-ethylene-butylene-styrene copolymer)
And the like. Examples of the material constituting the adhesive layer include pressure-sensitive adhesives such as rubber-based, acrylic-based, urethane-based, and silicone-based adhesives, solvent-based adhesives, ethylene-vinyl acetate-based copolymer (EVA) -based, and styrene-based adhesives. There is a hot melt adhesive such as an isoprene-styrene block copolymer (SIS). In addition, for example, a post-curing adhesive that is a microcapsule curing type can also be used. The post-curable adhesive includes, for example, an uncrosslinked unsaturated polyester adhesive, an uncrosslinked acrylic adhesive, and the like. When a soft touch layer made of a polyurethane-based thermoplastic elastomer is laminated on a polyolefin-based base layer, for example, a material constituting the polyolefin-based base layer that has been previously acid-modified or graft-modified is used. The adhesion can also be improved by blending these materials with an unmodified polyolefin or laminating a modified polyolefin substrate layer on an unmodified polyolefin substrate sheet.

The coating sheet used in the present invention may further contain a coloring agent such as a pigment or a dye, an antioxidant,
Materials such as an ultraviolet absorber and an ultraviolet stabilizer (for example, hindered amine) can be added. As the colorant, pigments and dyes used in paints can be used. Examples of the pigment include titanium oxide, iron oxide, carbon black, cyanine pigment, and quinacridone pigment. Examples of the dye include an azo dye, an anthraquinone dye, an indigoid dye, and a stilbenzene dye. Further, metal powder such as aluminum flake, nickel powder, gold powder, silver powder and the like may be used as the coloring agent. These materials are preferably fine particles as much as possible.
However, when these colorants are added, the soft touch feeling imparted by the elastic fine particles may be different, so that in a system to which the colorant is added, the appropriate amount of the elastic fine particles may change.

In order to impart various functions to the covering sheet used in the present invention, various functionalizing agents can be added. Examples of the functional imparting agent include a conductive material, a dew condensation preventing agent, and a photochromic compound. Further, the sheet may be subjected to patterning such as printing in order to enhance the design. In this case, the printing is preferably provided on the back surface (on the base material layer) of the soft touch layer.

The thickness of the covering sheet used in the present invention thus obtained varies depending on the sheet constitution.
Generally, the soft touch layer (surface layer) has a thickness of 5 to 500 μm.
m, base layer 200 to 3000 μm, foam layer 100
The thickness is preferably about 0 to 3000 μm. [Manufacturing Method of Molded Article Using Coating Sheet Obtained by the Present Invention] A molded article is manufactured using the coating sheet obtained by the present invention, for example, as follows.

1) A covering sheet is introduced into a mold in advance so that the soft touch layer becomes a surface, and a molding resin to be a molded article body is molded by injection molding or stamping molding, and at the same time, a sheet is formed on the molded article body surface. Attach the covering sheet. That is, after the soft touch layer of the sheet is introduced into the mold so as to face the surface of the molded article obtained, the mold is closed after the molding resin is introduced into the mold at the time of stamping molding, and at the time of injection molding. After closing the mold, a resin is introduced to obtain a molded product.

2) The covering sheet is preliminarily formed by pneumatic molding, and the preformed product is introduced into a mold so as to face the surface of the molded product from which the soft-touch layer is obtained, and then formed into a molded product body. The resin is molded by injection molding or stamping molding, and at the same time, the sheet is attached to the surface of the molded article body with the covering sheet. That is, at the time of stamping molding, the molding resin is introduced into the mold, and then the mold is closed. At the time of injection molding, the mold is closed, and then the resin is introduced to obtain a molded product.

Incidentally, the pneumatic forming means vacuum forming, compressed air forming and the like. Further, the preforming may be performed using a mold for performing resin molding such as injection molding, or another sheet forming mold may be used. As the molding resin used above, any material can be used as long as it is a material usually molded. For example, ABS (acrylonitrile-butadiene-styrene copolymer), polyethylene, polypropylene, polyvinyl chloride, polystyrene, polycarbonate, acrylic resin, polyetherimide, polyphenylene sulfide, nylon, and the above-mentioned thermoplastic elastomers, and furthermore, And those having glass fiber or inorganic filler as the material.

The molded article obtained by the method for producing a molded article of the present invention has a soft touch feeling on the product surface, and thus can be suitably used in places where humans can easily touch. That is, for example, automobile interior parts such as door panels, instrument panels, handles, gear lever knobs, door knobs, and various switches, portable products (telephones, cassette tape recorders, compact discs,
Housings for home appliances such as televisions, refrigerators, televisions, etc., housings for switches, etc., office automation products such as personal computers, printers, keyboards, etc., sanitary parts for Western-style toilet seats, bath tubs, chairs, mats, shelves, etc. Sporting goods, cases, such as products and chamber products, grips for bats, rackets, clubs, etc.
It can be used for daily necessities such as containers, housings for stationery products, benches, chairs, tables, sofas and the like.

[0032]

According to the above construction, the composition containing the thermoplastic elastomer and the elastic fine particles as the soft touch layer as the main components and the thermoplastic resin as the base layer are laminated by co-extrusion. The layers can be easily laminated without entrapping air between the layers.

Then, since the obtained sheet-like laminated body is stretched, the soft touch layer becomes the soft touch layer 1.
The soft touch layer can be easily stretched together with the base material layer even if the thickness is such that it is difficult to stretch only with the layer.

[0034]

EXAMPLES The present invention will be described below in detail by comparing Examples and Comparative Examples. In the following, "part"
Indicates parts by weight in terms of solid content.

Example 1 a) Soft touch layer material Thermoplastic urethane elastomer resin (Nippon Miractran Co., Ltd., E375MNAT, JIS-A hardness 75) 1
00 parts elastic beads (manufactured by Sekisui Plastics Co., Ltd., UB15 (black), crosslinked urethane elastic beads, average particle size 2
4 μm) 120 parts The thermoplastic elastomer and elastic beads were extruded with a twin-screw kneading extruder, and after cooling, pelletized with a soft cutter.

The temperature of each part of the extruder was set under the following conditions. Screw rear 140 ° C, middle 160
° C, 170 ° C at the front, 170 ° C at the die. b) Substrate layer material 80 parts of a thermoplastic olefin elastomer (manufactured by Mitsui Petrochemical Co., Ltd., Mirastomer 8030N) and 20 parts of low density polyethylene (LLPE) are pellet-blended. c) Adhesive layer Acid-modified SEBS (ToughTech M1943, manufactured by Asahi Kasei Kogyo Co., Ltd.) The above three layers a), b), and c) were each made of 50φ, 40φ, 40
The extruder was extruded downward from a three-layer coextrusion apparatus 2 equipped with extruders 1a, 1b, 1c of φ and a multi-manifold type die. Each resin temperature is 180 ° C. for a) and 2 for b).
10 ° C, c) was 210 ° C and the die temperature was 190 ° C.

The mold lip (width 2) is extended while being cooled by air.
mm, 1m in length) and the temperature is about 170
° C while taking up while stretching by a cooling take-off roll 3 at a temperature of 40 ° C rotating at a higher speed than the discharge speed of the resin. It was introduced and pressed between the roll 3 and the laminating roll 8 to laminate and integrate the laminate 4 and the sheet 6 to obtain a covering sheet 7.

The thickness of the soft touch layer, the adhesive layer, the base material layer, and the foam layer of the obtained laminating sheet 7 was 50 μm for the soft touch layer, 30 μm for the adhesive layer, 400 μm for the base material layer, and The body layer was 2000 μm, and the lip cross-sectional area / cross-sectional area of the obtained sheet = 5.

Example 2 a) Soft touch layer material Thermoplastic urethane elastomer resin (Nippon Miractran Co., Ltd., E785QSDH, JIS-A hardness 85) 1
00 parts Elastic beads (EAX15 (black), crosslinked acrylic acid ester elastic beads, average particle size 15 μm, manufactured by Sekisui Plastics Co., Ltd.) 60 parts The above thermoplastic elastomer and elastic beads are biaxially kneaded and extruded. After extrusion and cooling, the mixture was pelletized with a soft cutter.

The set temperature of each part in the extruder was set under the following conditions. Screw rear 150 ° C, middle 165
° C, front 175 ° C, die 175 ° C. b) Substrate layer material Thermoplastic olefin elastomer (Mitsui Petrochemical Industries
8030N), 20 parts of LLPE
Part pellet blended. c) Adhesive layer Acid-modified SEBS (ToughTech M1943, manufactured by Asahi Kasei Corporation) The above three layers a), b) and c) were co-extruded downward in the same manner as in Example 1. Each resin temperature is a) 18
0 ° C, b) 210 ° C, c) 210 ° C, die temperature 1
90 ° C. The apparatus used and other conditions were the same as those in Example 1, but the temperature of the sheet-like laminate 4 at a position about 15 cm immediately below the mold lip was about 180 ° C.

The sheet-like laminate 4 is formed by the take-off roll 3.
Was stretched, and a foamed polypropylene sheet (expansion ratio 25 times) 6 was laminated in the same manner as in Example 1 to obtain a coating sheet 7. When the soft touch layer 5 of the obtained coating sheet 7 was confirmed with an electron microscope, fine irregularities were obtained on the surface. The thickness of the soft touch layer, the adhesive layer, the base material layer, and the foam layer of the obtained covering sheet 7 is as follows:
The soft touch layer is 100 μm and the adhesive layer is 10
0 μm, base layer 300 μm, foam layer 3000 μm
Lip cross-sectional area / cross-sectional area of obtained sheet = 7.

Example 3 Thermoplastic urethane elastomer resin (Nippon Miractran Co., Ltd., E375MNAT, JIS-A hardness 75) 1
00 part elastic beads (CU Chemie Uetikon A
G, 100 parts of deco silk (transparent NY18), polyurethane elastic beads, average particle size 18 μm) The thermoplastic elastomer and elastic beads were extruded by a twin-screw kneading extruder, and after cooling, pelletized by a soft cutter.

The set temperature of each part in the extruder was set under the following conditions. Screw rear 140 ° C, middle 160
° C, 170 ° C at the front, 170 ° C at the die. b) Substrate layer material 80 parts of a thermoplastic olefin elastomer (Mitsui Oil Chemical Co., Ltd., Mirastomer 8030N) and 20 parts of low density polyethylene are pellet-blended. c) Adhesive layer Acid-modified SEBS (Tuftec M1943, manufactured by Asahi Kasei Corporation) The above three layers a) and b) c) were co-extruded downward as in Example 1. Each resin temperature is a) 180 ° C,
b) 210 ° C., c) 210 ° C., die temperature 190 ° C.
Met.

The obtained sheet laminate was stretched twice at 140 ° C. by a tenter stretching apparatus to obtain a soft touch sheet. The soft touch layer of the obtained soft touch sheet had fine irregularities on the surface confirmed by an electron microscope. Next, the surface of the substrate layer of the soft touch sheet was
While heating to 50 ° C., the surface was laminated on a foamed polypropylene sheet (expansion ratio: 25 times) whose surface was heated to 170 ° C. to obtain a coating sheet.

The soft touch layer of the obtained covering sheet,
The thicknesses of the base layer, the adhesive layer, and the foam layer were 50 μm for the soft touch layer, 300 μm for the base layer, and 80 μm for the adhesive layer, and 2000 μm for the foam layer, respectively.

Example 4 Thermoplastic urethane elastomer resin (manufactured by Dainippon Ink and Chemicals, T-7890, JIS-A hardness 91) 1
00 parts Elastic beads (UB15 (black), cross-linked polyurethane elastic beads, average particle size 24 μm, manufactured by Sekisui Chemical Co., Ltd.) 120 parts The thermoplastic elastomer and elastic beads are extruded with a twin-screw kneading extruder. After cooling, it was pelletized with a soft cutter.

The set temperature of each part in the extruder was set under the following conditions. Screw back 200 ° C, middle 210
℃, front part 210 ° C, die part 205 ° C b) Base layer material 80 parts of a thermoplastic olefin elastomer (Mitsui Oil Chemical Co., Ltd., Mirastomer 80 30N) pellet blended with 20 parts of low density polyethylene. c) Adhesive layer The acid-modified SEBS (Taftec M1943, manufactured by Asahi Kasei Kogyo Co., Ltd.) Three layers a), b) and c) were coextruded. The resin temperatures of a) are 210 ° C., b) is 210 ° C., and c) is 2
The temperature of the die was 190 ° C. The apparatus used and other conditions were the same as in Example 1, except that the temperature of the sheet-like laminate 4 at a position about 15 cm immediately below the mold lip was about 160 ° C.

The take-up roll 3 causes the sheet-like laminate 4
Was expanded, and a foamed polypropylene sheet (expansion ratio 25 times) 6 was laminated in the same manner as in Example 1 to obtain a sheet 7 for coating. When the soft touch layer 5 of the obtained coating sheet 7 was confirmed with an electron microscope, fine irregularities were obtained on the surface. The thickness of the soft touch layer, the adhesive layer, the base material layer, and the foam layer of the obtained coating sheet 7 was 100 μm for the soft touch layer, 70 μm for the adhesive layer, respectively.
The base material layer was 1000 μm, the foam layer was 3000 μm, and the lip cross-sectional area / cross-sectional area of the obtained sheet was 7.

Comparative Example 1 Thermoplastic urethane elastomer resin (manufactured by Nippon Milactran Co., Ltd., E375MNAT, JIS-A hardness 75)
100 parts Immediately after extruding the thermoplastic elastomer with a twin-screw kneading extruder, the sheet is stretched and taken up by a cooling take-up roll set at 40 ° C., and at the same time, between the take-up roll and the laminated roll paired, 170 surface
A foamed polypropylene sheet heated to ° C. was introduced and laminated under pressure to obtain a sheet for coating.

The set temperature of each part in the extruder was as follows. Screw rear 140 ° C, middle 180
° C, 170 ° C at the front, 170 ° C at the die. Lip cross-sectional area / sheet cross-sectional area = 10, and the elastomer sheet was elongated by the take-off roll. However, when confirmed by an electron microscope, fine unevenness was not obtained on the sheet surface.

(B) Method for Producing Molded Article (B) -1 Injection Molding Using the coating sheets obtained in Examples 1 to 4 and Comparative Example 1, the following steps were carried out using an injection molding machine shown in FIGS. Injection molding was carried out according to the method shown in (1) to obtain a molded product.

As shown in FIG. 2, this injection molding machine comprises a movable mold 10 having a concave portion 10a for molding and a vent 10b for drawing a vacuum, and a fixed mold 12 having a convex portion 12a.
And both dies 10 and 12, and both dies 1
The apparatus includes a hot platen 14 having holes for vacuum and compressed air and a resin injection machine 15 that can move outward from between 0 and 12.

First, as shown in FIG. 3, a coating sheet 13 is disposed between the moving mold 10 and the hot platen 14, and the sheet 13 is heated while being sucked by the hot platen 14, The sheet 13 was subjected to vacuum and / or pressure forming, and was brought into close contact with the inner surface of the concave portion 10a of the mold 10 as shown in FIG. next,
The hot platen 14 was moved outward from between the two dies 10, 12, and thereafter, as shown in FIG. 4, the movable dies 10 were moved to the fixed dies 12 to close the dies. Next, the molding resin was injected from the resin injection machine 15 into the cavity formed by the two molds 10 and 12 at a nozzle tip temperature of 230 ° C. The resin used is polypropylene (BC3, manufactured by Mitsubishi Yuka Corporation). After molding, the molded product was taken out of the mold to obtain an injection molded product. Table 1 shows the molding temperature of the sheet of each example or comparative example, the appearance of the obtained molded product, and the soft touch feeling.

[0054]

[Table 1]

* Evaluation of soft touch feeling on elastomer sheet side in Comparative Example 1 1 point: Not soft touch 2 points: Not soft touch 3 points: Soft touch 10 persons evaluated A total of 25 points or more was regarded as good, and a total of 15 points or less was regarded as bad.

(B) -2 Stamping Molding Using the covering sheets obtained in Examples 1 to 4 and Comparative Example 1, stamping molding was performed by a stamping molding apparatus shown in FIGS. 6 to 9 according to the following method. This molding machine has an upper mold 20, a lower mold 21, and a resin injection machine 22, as shown in FIG. A projection 20a is provided on the lower surface of the upper mold 20.
Is provided on the upper surface of the lower mold 21 at a position corresponding to the convex portion 20a. In addition, lower mold 2
A resin injection path 21b is formed in the center of the resin injection path 1, and a nozzle 22a of a resin injection machine 22 is provided in the resin injection path 21b.

First, as shown in FIG. 7, the covering sheet 23 is introduced between the upper mold 20 and the lower mold 21 heated to a predetermined temperature, and the periphery of the sheet 23 is Was fixed with fixing pins 24. Next, as shown in FIG. 8, the molding resin 25 was injected into the lower mold 21 from the nozzle 22 a of the resin injection machine 22 at a nozzle tip temperature of 230 ° C. As the molding resin 25, polypropylene (manufactured by Mitsubishi Yuka Corporation,
BC3) was used. Next, as shown in FIG. 9, the upper mold 20 was closed at a predetermined pressure to form the sheet 23 and the resin 25 was stamped to obtain a molded article 27 having the shape shown in FIG. 9 and 10 in the L ₁ is 200 mm, L
₂ 300 mm, L ₃ is 30 mm, L ₄ is 150 mm, L ₅ is 280 mm, L ₆ is 60 mm, L ₇ is 500 mm. Table 2 shows the preheating temperature of the sheet of each Example or Comparative Example, the appearance of the obtained molded product, and the soft touch feeling.

[0058]

[Table 2]

* In Comparative Example 1, evaluation of soft touch feeling on elastomer sheet side: 1 point: Not soft touch 2 points: Not slightly soft touch 3 points: Soft touch 10 people evaluated A total of 25 points or more was regarded as good, and a total of 15 points or less was regarded as bad.

[0060]

The method for manufacturing a molded article according to the present invention is configured as described above, so that it only covers the surface of the molded article and provides a soft touch feeling when touched and a matte appearance on the touch appearance. It is possible to easily obtain a covering sheet that can give a feeling to a molded article. When the covering sheet obtained by the present invention is used, a molded product having a soft touch (suede) feel can be easily and inexpensively obtained by a molding method such as injection molding or stamping molding.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing an example of an apparatus for implementing a method for producing a covering sheet according to the present invention.

FIG. 2 is an explanatory diagram of an injection molding machine used when manufacturing a molded product using the covering sheets obtained in Examples 1 to 4 and Comparative Example 1.

FIG. 3 is an explanatory diagram illustrating a state before a coating sheet is preformed by the injection molding machine of FIG. 2;

FIG. 4 is an explanatory view illustrating a state in which a coating sheet is preformed by the injection molding machine of FIG. 2;

FIG. 5 is an explanatory diagram illustrating a state in which a molding resin to be a molded article main body is injection-molded.

FIG. 6 is an explanatory diagram of a stamping molding apparatus used when producing molded articles using the covering sheets obtained in Examples 1 to 4 and Comparative Example 1.

FIG. 7 is an explanatory diagram illustrating a state in which a covering sheet is set on a lower mold of the stamping molding device of FIG. 6;

8 is an explanatory view illustrating a state in which a molding resin serving as a molded article main body is injected into a lower mold of a stamping molding apparatus in which the covering sheet of FIG. 7 is set.

9 is an explanatory diagram illustrating a state in which the upper mold is closed to the lower mold into which the molding resin of FIG. 8 has been injected and stamping molding has been performed.

FIG. 10 is a cross-sectional view of a molded product obtained by stamping molding.

[Explanation of symbols]

 4 Sheet laminate 5 Soft touch layer 6 Foamed polypropylene sheet (foam layer) 7 Sheet for covering

────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-59-138452 (JP, A) JP-A-56-56846 (JP, A) JP-A-3-90329 (JP, A) JP-A-3- 99847 (JP, A) JP-A-3-207638 (JP, A) JP-A-3-207730 (JP, A) JP-A-3-71828 (JP, A) JP-A-3-279474 (JP, A) JP-A-57-20344 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B29C 47/00-47/98 B32B 1/00-35/00

Claims (1)

(57) [Claims] 1. A composition for a soft touch layer containing a thermoplastic elastomer and elastic fine particles as main components,
After stretching a sheet-like laminate obtained by co-extruding a thermoplastic resin to be a base layer to obtain a soft touch sheet, a foam layer is laminated on the base layer side of the soft touch sheet. A method for producing a covering sheet.