JPH0257309A - Thermoplastic elastomer molded product with emboss pattern and its manufacture - Google Patents

Abstract

PURPOSE:To manufacture a molded product with deep emboss and without lowered mechanical physical properties by bonding closely thermoplastic elastomer powder containing polyolefin resin and ethylene. alpha-olefin copolymer rubber in the fluidization plasticized state on the inner surface of an emboss pattern transfer mold in the revolving and heated state and melding thereon. CONSTITUTION:Thermoplastic elastomer powder containing polyolefin resin and ethylene. alpha-olefin copolymer rubber is put in an emboss pattern transfer mold 1 and said mold 1 is sealed. Then, the emboss pattern transfer mold 1 is heated (usually 150-210 deg.C) while revolved, and the thermoplastic elastomer powder in the fluidization plasticized state adheres closely on the inner surface of the mold and melted thereon. As the emboss pattern transfer mold 1 is heated while revolved by using the thermoplastic elastomer powder, the powder in the mold 1 is fluidization plasticized and infiltrated deep into the inside of emboss formed on the inner surface of the mold 1, adheres closely on the inner surface of the mold 1 and melted thereon. Thus, a thermoplastic elastomer molded product with deep emboss pattern can be manufactured.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thermoplastic elastomer molded article with a textured pattern and a method for producing the same, and more specifically, it relates to a thermoplastic elastomer molded product with a textured pattern and a method for manufacturing the same. The present invention relates to a thermoplastic elastomer molded product having excellent mechanical properties, and a method for producing the same.

Conventionally, vinyl chloride resin (
pvc) is widely used. In particular, there is a high demand for embossed patterns, such as automobile dash boards, which have a strong image of luxury.

By the way, as a method for manufacturing vinyl chloride resin molded articles with grain patterns such as automobile dash boards and dolls as described above, a vinyl chloride resin powder for plastisol with a plasticizer such as dioctyl phthalate added thereto is injected into a mold. Alternatively, the so-called slush molding method, in which a mold is immersed in the powder, the powder is adhered to the surface of the mold, and molded by heating, is used to form a vinyl chloride resin sheet (PvC
A method of vacuum forming a sheet (sheet) is known.

However, vinyl chloride resins have problems in that they are inferior in heat resistance, heat aging resistance, cold resistance, and light resistance. Also,
Even if a molded article with a grain pattern is produced by slush molding or vacuum forming using vinyl chloride resin as described above, the depth of the grain is about 90 μm. Therefore, the synthetic resin molding has a deeper grain pattern. The appearance of things was desired.

The present inventors conducted intensive research to obtain a synthetic resin molded product with a deeper grain pattern to replace the grained vinyl chloride resin molded product described above, and found that polyolefin resin and ethylene/α-olefin resin It has been shown that by rotationally molding a thermoplastic elastomer powder containing polymer rubber, a molded product with no deterioration in mechanical properties, deep grain depth, and excellent transferability of the grain pattern can be obtained. This discovery led to the completion of the present invention.

The present invention aims to solve the problems associated with the prior art as described above, and is an alternative to the textured vinyl chloride resin molded product, which has a deeper texture and is mechanically more stable. The object of the present invention is to provide a thermoplastic elastomer molded article with a textured pattern without deterioration in physical properties.

Another object of the present invention is to provide a method for manufacturing a thermoplastic elastomer molded article with a textured pattern as described above.

Nine skins 2. The textured thermoplastic elastomer molded product according to the present invention has a textured pattern in which a thermoplastic elastomer powder containing a polyolefin resin and an ethylene/α-olefin copolymer rubber is heated by rotation. It is characterized by a textured pattern being formed on the surface by closely adhering to and melting the inner surface of the transfer mold in a flowing plastic state.

The method for producing a thermoplastic elastomer molded article with a textured pattern according to the present invention is to place a thermoplastic elastomer powder containing a polyolefin resin and an ethylene/α-olefin copolymer rubber into a mold for transferring the textured pattern. After filling the mold and sealing the mold, the mold is heated while being rotated so that the thermoplastic elastomer powder adheres to the inner surface of the mold in a flowing plastic state and melts, and then the mold is cooled. It is characterized by obtaining a thermoplastic elastomer molded product having a grain pattern on the surface.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The textured thermoplastic elastomer molded article and the method for producing the same according to the present invention will be specifically described below with reference to the drawings.

FIG. 1 is a schematic cross-sectional view of a rotational molding apparatus used in manufacturing a thermoplastic elastomer molded article with a textured pattern according to the present invention.

First, the textured thermoplastic elastomer molded article according to the present invention will be explained.

The thermoplastic elastomer powder used in the present invention is a powder containing a polyolefin resin and an ethylene/α-olefin copolymer rubber as essential components.

In the present invention, the ethylene/α-olefin copolymer rubber is preferably a partially crosslinked ethylene/α-olefin copolymer rubber;
- Non-crosslinked olefin copolymer rubber may be used.

Specific examples of preferable thermoplastic elastomers used in the present invention include the following thermoplastic resin compositions.

(I) Various polyolefin resins represented by homopolymers of ethylene or propylene or copolymers with small amounts of other polymerizable monomers, and ethylene with 3 to 1 carbon atoms.
Mixture of binary copolymer rubber with α-olefin of 4 or a partially crosslinked product of ethylene/α-olefin copolymer rubber, which is a terpolymer rubber obtained by further copolymerizing various polyethylene compounds. Thermoplastic resin compositions obtained by A thermoplastic resin composition obtained by dynamically heat-treating the body in the presence of a small amount of a crosslinking agent (for example, Japanese Patent Publication No. 53-34210, Japanese Patent Application Laid-open No. 53-34210)
Publication No. 149240, and JP-A-53-149241
(2) A thermoplastic resin composition obtained by further blending a polyolefin resin with the composition (I) or (II) above (for example, JP-A-53-145857 and (Refer to Publication No. 16554/1983), (IV
) Peroxide crosslinked polyolefin resins represented by homopolymers of ethylene or copolymers with small amounts of other polymerizable monomers, homopolymers of propylene or copolymers with small amounts of other polymerizable monomers. A thermoplastic resin obtained by dynamically heat-treating a blend of a peroxide non-crosslinked polyolefin resin represented by a polymer and an ethylene/α-olefin copolymer rubber in the presence of a small amount of peroxide. Compositions (for example, JP-A-55
-71739) etc.

In these various thermoplastic elastomers, the polyolefin resin and the ethylene/α-olefin polymer rubber have a superposition ratio of usually 90/1.0 to 10/90, preferably 80/20 to 20/80. It is used like this.

As a polyolefin resin, polyethylene, especially low density polyethylene and volip 11 pyrene are mixed at 1.0/90 for the purpose of improving moldability, scratch resistance, etc.
They can be mixed and used at a stacking ratio of ~70/30.

In addition, the ethylene/α-olefin polymer rubber has a molar ratio of ethylene to α-olefin of 50,150 to 90/10, preferably 7, mainly for strength reasons.
'O/30 to 85/15, and the Mooney viscosity ML (1211+4°C) is about 20 to 12, preferably about 40 to 80! )
When partially crosslinking these ethylene/α-olefin polymer rubbers, it is generally preferable to use ethylene/α-olefin polymer rubbers of approximately 0.1 It is preferable to carry out dynamic heat treatment using a ~double-layer organic peroxide.

In the thermoplastic elastomer of the present invention, a peroxide non-crosslinked hydrocarbon rubber-like substance typified by polyisobutylene, butyl rubber, etc. and/or a mineral oil-based softener may be included in the thermoplastic resin composition as necessary. You can also do it.

The thermoplastic elastomer powder used in the present invention has a mesh size of 40 to 100 meshes, preferably 60 to 80 meshes, and has a particle size of 40 to 100 meshes, preferably 60 to 80 meshes.
- can be obtained, for example, by grinding.

The present invention has good flexibility, scratch resistance, heat resistance, and cold resistance, has little temperature dependence of flexibility, and does not have a sticky surface like plasticizer-containing soft polyvinyl chloride. Thermoplastic elastomer powder is used.

In the present invention, the expression that the grain pattern transfer mold 1 is "in a rotational heating state" refers to a state in which the grain pattern transfer mold 1 is heated, for example, by the heater 2 while being rotated. When the grain pattern transfer mold 1 is in a rotational heating state, the thermoplastic elastomer powder in the sealed grain pattern transfer mold 1 becomes fluid and plastic, and the inside of the grain pattern transfer mold 1 is heated. A thermoplastic elastomer molded article with a textured pattern is obtained by melting in close contact with the surface and forming a textured pattern on the surface.

In the present invention, polyolefin resin and ethylene
The thermoplastic elastomer powder containing α-olefin copolymer rubber penetrates deeply into the grains on the inner surface of the grain pattern transfer mold 1, which has fine irregularities, and adheres closely to the mold inner surface. Therefore, deeper grains can be obtained compared to conventional molded products made of vinyl chloride resin with grain patterns.

Incidentally, in the present invention, a thermoplastic elastomer molded product with a grain pattern can be obtained with a grain depth of 150 μm or more, whereas with conventional vinyl chloride resin, the grain depth is 90 μm or more.
The limit was to obtain a molded product of about m.

Next, a method for manufacturing a textured thermoplastic elastomer molded article according to the present invention will be described.

First, the thermoplastic elastomer powder is placed in the grain pattern transfer mold 1, and the mold 1 is sealed.

In the present invention, since a thermoplastic elastomer containing a polyolefin resin and an ethylene/α-olefin copolymer rubber is used, the shape of the mold 1 is not particularly limited, and molds of various shapes can be used. It is also possible to produce deep drawn products.

Next, the grain pattern transfer mold 1 is heated while being rotated, so that the thermoplastic elastomer powder is brought into close contact with the inner surface of the mold in a flowing plastic state and melted.

The heating temperature is usually 150 to 210°C.

In the present invention, since the thermoplastic elastomer powder is heated while rotating the grain pattern transfer mold 1, the powder in the mold 1 becomes fluid and plasticized and forms on the inner surface of the mold 1. It penetrates deeply into the applied grain, adheres to the inner surface of the mold 1, and melts. Therefore, in the present invention, a thermoplastic elastomer molded article with a deep grain pattern can be obtained.

Next, the grain pattern transfer mold 1 is cooled to obtain a thermoplastic elastomer molded product having a grain pattern on its surface.

Examples of the cooling method include air cooling, water cooling, and the like.

The textured thermoplastic elastomer molded product obtained by the production method according to the present invention has excellent scratch resistance, appearance, and texture.
By applying the surface treatment described in 2-331718 to the surface of the molded product, even better scratch resistance,
A thermoplastic elastomer molded article with a textured appearance and texture is obtained.

That is, as the surface treatment, first, saturated polyester,
A top coat comprising a primer layer containing at least one compound selected from chlorinated polyolefins, and further comprising at least one compound selected from saturated polyesters, acrylic ester resins, and isocyanate resins on the primer layer. form a layer. However, if the primer layer contains only saturated polyester out of at least one compound selected from saturated polyester and chlorinated polyolefin, the top coat layer must not contain at least an acrylic ester resin. No.

To form a primer layer on the surface of the molded product, at least one compound selected from saturated polyester and chlorinated polyolefin is dissolved in an organic solvent, and the resulting coating solution for forming a primer layer is molded according to a conventional method. Just apply it on the surface of the object.

In addition, in order to form a top coat layer on the primer layer, at least one compound selected from saturated polyester, acrylic ester resin, and isocyanate resin is dissolved in an organic solvent, and the resulting top coat layer forming coating is used. The solution may be applied onto the primer layer according to a conventional method.

The textured thermoplastic elastomer molded product according to the present invention is a thermoplastic elastomer molded product containing a polyolefin resin and an ethylene/α-olefin copolymer rubber, which is heated in a rotationally heated state to transfer the textured pattern. By melting in close contact with the inner surface of the mold, a grained pattern is formed on the surface, so it is not only possible to create a grained pattern with a shallow grain depth, but also to create a textured PVC resin with a conventional grained pattern. Compared to a molded product, it has the effect of being able to form a grain pattern with a deeper grain depth, and also has the effect of not deteriorating mechanical properties.

Moreover, according to the manufacturing method according to the present invention, a thermoplastic elastomer molded article with a textured pattern having the above-mentioned effects can be obtained.

EXAMPLES The present invention will be explained below with reference to Examples, but the present invention is not limited to these Examples.

Tue 1102 [Method for producing thermoplastic elastomer powder] Thermoplastic elastomer powder was produced in the following manner using the following components.

(Component A) Ethylene/propylene/ethylidene norbornene ternary copolymer rubber; ethylene unit/propylene unit (molar ratio) near 8/22, iodine value 15, Mooney viscosity (ML, 121°C) 611+4 (Component B) Iso Tactical polypropylene resin: melt index 13ir/10 minutes (230°C) (component C) naphthenic process oil (component D) 20% by weight of 1,3-bis(tert-butylperoxyisopropyl)benzene, 30% by weight of divinylbenzene and A mixture consisting of 50% by weight of paraffinic mineral oil: 1 part by weight of 55 parts (component A), 45 parts by weight of (component B) and 30 parts by weight of (component C) were mixed in a Banbury mixer under a nitrogen atmosphere at 180°C for 5 minutes. After kneading for 1°, the obtained kneaded product was cut into a square pellet shape using a sheet cutter.

This square bellet L-100 multilayer part was kneaded with one multilayer part (component D) using a Henschel mixer, and extruded using an extruder at 220°C under a nitrogen atmosphere to produce a thermoplastic elastomer pellet.

The thermoplastic elastomer pellet thus obtained was pulverized in an atmosphere of -60°C to obtain a thermoplastic elastomer powder of 40 to 80 meshes.

[Manufacture of molded product] First, the above thermoplastic elastomer powder was poured into a mold for transferring the grain pattern, which was a mold for two automobile dash boards and had a grain pattern with a grain depth of 150 μm on the inner surface. After several people have left, the air in this mold is replaced with nitrogen.
This prevents the thermoplastic elastomer from deteriorating due to oxidation.

Next, while rotating the mold, the mold was heated to 210° C. from the outside with a heater to fluidize and melt the thermoplastic elastomer powder in the mold. During this time, heating was performed at 150°C for 5 minutes and at 210°C for 15 minutes.

Finally, this mold was cooled with water for 10 minutes to bring it to room temperature (1) to obtain a thermoplastic elastomer molded article with a textured pattern.

The size of the obtained thermoplastic elastomer molded product with a grain pattern was 1200 mm in length, 500 mm in width, and 1.0 m in thickness.
It was power.

Obtained grain 4! ! The tensile properties, surface hardness, torsional rigidity, permanent elongation, heat aging properties, grain depth, soft feel, and gloss of thermoplastic elastomer molded products with type I were evaluated.
Evaluation was made by the method described below. The sample for evaluation is
Punch out samples from the obtained molded product.

[Evaluation method] (1) Tensile properties According to JIS-6301 method.

(2) Surface hardness According to the JISA type method described in JIS-6301.

(3) Torsional rigidity: Based on the method of ASTH1043.

(4) Permanent elongation: According to JIS-6301 method.

(5) Heat aging properties After the sample was left in an air oven at 120°C for 1000 hours, the sample was taken out and measured using the JIS-6301 tensile test method.

(6) Grain depth The distance from the top of the embossing transferred to the surface of the molded article to the bottom of the valley was measured.

(7) Soft feel The surface of the molded product was touched with the hand and the feel was ranked in five levels.

5...Very soft 4...Soft 3...Original 2...Hard 1...Very hard (8) Gloss 60
It was irradiated at an incident angle of 100 degrees, and the reflectance was expressed as %.

The results are shown in Table 1.

1. The thermoplastic elastomer in Example 1 was molded using a T-die extrusion molding machine with a diameter of 90 mm manufactured by Toshiba, using a screw or full-flight extrusion molding machine. /D is 22 and extrusion temperature is 220
℃, extruded into a sheet with a thickness of 1.0 cm using a T-die or coat hanger die at a take-up speed of 5 m/min, and cooled with a cooling roll (0-low temperature 35°C) to form a sheet. I got it.

The obtained sheet was subjected to the same evaluation as in Example 1.

The results are shown in Table 1.

X Ri ±1 In Example 1, except that (component A) was made into 80-fold flat plate, (component B) was made into 20-fold plate, and (component E) was added with 10-fold plate part of butyl rubber (11R065 manufactured by Esso).
A molded article was obtained in the same manner as in Example 1, and the same evaluation as in Example 1 was performed on the obtained molded article.

The results are shown in Table 1.

The thermoplastic elastomer in Example 2 was molded using a Toshiba 90 mm T-die extrusion molding machine, the screw was in full flight, L/D was 22, and the extrusion temperature was 220°C.
The material was extruded into a sheet with a thickness of 1' and 100 mm using a 1'-die or a coat hanger die at a take-up speed of 5 m/min, and was cooled with a cooling roll (roll temperature: 35°C) to obtain a sheet. .

The obtained sheet was subjected to the same evaluation as in Example 1.

The results are shown in Table 1.

In Example 1, a molded product was obtained in the same manner as in Example 1, except that (component C) was not used, and the obtained molded product was evaluated in the same manner as in Example 1.

The results are shown in Table 1.

The thermoplastic elastomer in Example 3 was manufactured by Toshiba 90I.
Using a lj1φ T-die extrusion molding machine, the screw was in full flight, L/D was 22, and the extrusion temperature was 2.
20℃, T-die or coat hanger die,
1.0I1m under the condition of take-up speed 5m/min
It was extruded into a sheet having a thickness of r-% and cooled with a cooling roll (roll temperature: 35°C) to obtain a sheet.

The obtained sheet was subjected to the same evaluation as in Example 1.

The results are shown in Table 1.

To (-2L

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view of a rotational molding apparatus used in manufacturing a thermoplastic elastomer molded article with a textured pattern according to the present invention. 1... Mold for grain pattern transfer 2... Heater

Claims (1)

[Scope of Claims] 1) A thermoplastic elastomer powder containing a polyolefin resin and an ethylene/α-olefin copolymer rubber is applied to the inner surface of a mold for transferring grain patterns under rotational heating. A thermoplastic elastomer molded article with a textured pattern, characterized in that a textured pattern is formed on the surface by closely contacting and melting in a state. 2) A thermoplastic elastomer powder containing a polyolefin resin and an ethylene/α-olefin copolymer rubber is placed in a grain pattern transfer mold, the mold is sealed, and the mold is rotated. The thermoplastic elastomer powder is brought into close contact with the inner surface of the mold in a flowing plastic state by heating while heating, and then the mold is cooled to obtain a thermoplastic elastomer molded product having a grain pattern on the surface. A method for producing a characteristic thermoplastic elastomer molded product.