JPH0416313A - Embossed thermoplastic elastomer formed matter and manufacture thereof - Google Patents

Abstract

PURPOSE:To obtain a formed matter, the embossing depth of which is deeper than usual and the mechanical properties of which do not deteriorate, by a method wherein powdered mixture containing polyolefin-based resin and alpha-olefin- based copolymer rubber is brought in the presence of crosslinking agent under fluidized and plasticized state into close contact with the inner surface of an emboss transferring mold under rotatingly heated condition and finally melted. CONSTITUTION:Powdered mixture containing polyolefin-based resin and alpha-olefin- based copolymer rubber is put in the presence of crosslinking agent in an emboss transferring mold 1 and then the mold 1 is sealed. Next, by heating the mold 1 as being rotated with heaters 2 so as to fluidize and plasticize the powdered mixture in order to bring the mixture into close contact with the inner surface of the mold 1 and then melt the mixture. After that, the mold 1 is cooled down so as to obtain a thermoplastic elastomer formed matter having emboss on its surface.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a thermoplastic elastomer molded product with a textured pattern and a method for manufacturing the same, and more particularly, to a machine having a textured pattern consisting of fine irregularities on the surface, particularly a deep textured pattern. The present invention relates to a thermoplastic elastomer molded product with excellent physical properties and a method for producing the same.

Technical disadvantages of the invention and its problems Conventionally, vinyl chloride resin (PVC) has been widely used for molded products such as automobile dash boards and dolls. In particular, automatic Ichikawa Dashboards with grain patterns, for example, are in high demand because they have a strong image of luxury.

By the way, as a method for manufacturing vinyl chloride resin molded products with grain patterns such as automobile dash boards and dolls as mentioned above, a plasticizer such as dioctyl phthalate is added to a plastisol river vinyl chloride resin powder is used in a mold. The so-called slush molding method involves injecting the mold into the powder, or immersing the mold in the powder to adhere the powder to the mold surface and molding by heating.
A method of vacuum forming a VC 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 α-olefin copolymer If a mixture of powder and rubber containing rubber is rotomolded in the presence of a crosslinking agent,
It was discovered that a molded article with no deterioration in mechanical properties, deep grain depth, and excellent transferability of the grain pattern could be obtained, and the present invention was completed.

Purpose of the Invention The present invention aims to solve the problems associated with the prior art as described above, and is an object of the present invention to provide a material with deeper grain depth and improved mechanical properties as an alternative to the grained vinyl chloride resin molded product. The object of the present invention is to provide a thermoplastic elastomer molded product with a grain pattern that does not deteriorate.

Another object of the present invention is to provide a method for producing a thermoplastic elastomer molded article with a grain pattern as described above, which can omit the thermoplastic elastomer production process and the powdering process.

Summary of the Invention The textured thermoplastic elastomer molded product according to the present invention is produced by forming a textured molded article in which a mixture powder containing a polyolefin resin, an α-olefin copolymer rubber, and a grain is heated in a rotating state in the presence of a crosslinking agent. It is characterized in that a textured pattern is formed on the surface by closely contacting and melting the inner surface of the pattern transfer mold in a flowing plastic state.

The method for producing a thermoplastic elastomer molded product with a textured pattern according to the present invention is to apply a mixture powder containing a polyolefin resin and an α-olefin copolymer rubber to a mold for transferring the textured pattern in the presence of a crosslinking agent. After placing the powder inside and sealing the mold, the mold is heated while being rotated so that the mixture powder adheres to the inner surface of the mold in a fluid 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 its surface.

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

First, the textured heat-11 plastic elastomer molded product according to the present invention will be explained.

In the present invention, a mixture powder containing a polyolefin resin and an a-olefin copolymer rubber as essential components is used.

Examples of the polyolefin resin used in the present invention include ethylene or propylene 11 monopolymer, or ethylene or propylene with a small amount of other m-polymer 11
For example, propylene-ethylene copolymer, propylene-1-butene copolymer, propylene-l-hexene JI: polymer, propylene-4-methyl-1-pentene copolymer, etc. can be mentioned. Specific examples of the above-mentioned small amounts of other polymerizable Lit Q forms include vinyl acetate, ethyl acrylate, and methacrylic acid. In the present invention, polyolefin resin melt integer (ASTM-1)-1238-6
51,230'C) is r), 1-100, especially 5-5
It is preferably within the range of 0.

As the polyolefin resin, polyethylene, especially low density polyethylene and polypropylene, are used in the range of 10/90 to 7 for the purpose of improving moldability and scratch resistance of the sheet.
They can be used by mixing at a weight ratio of 0/30.

The a-olefin copolymer rubber used in the present invention is
For example, ethylene-propylene copolymer rubber, propylene-ethylene copolymer rubber, ethylene-propylene non-conjugated diene rubber, propylene-ethylene non-conjugated diene rubber, ethylene-butadiene (polymer rubber, propylene-
An amorphous elastic copolymer mainly composed of olefins, such as butadiene copolymer rubber. When mixed with an organic peroxide and kneaded under heat, it crosslinks and reduces its fluidity or becomes fluid. It is a rubber that disappears. In addition,
The non-conjugated diene refers to dicyclopentadiene, 1,4-hexadiene, dicyclooctadiene, methylene norbornene, ethylidene norbornene, and the like.

In the present invention, among these copolymer rubbers, ethylene-propylene non-conjugated diene copolymer rubber, especially ethylene-propylene-ethylidene norbornene copolymer rubber, is a thermoplastic rubber with excellent heat resistance, tensile properties, and rebound resilience. This is preferable in that an elastomer molded article can be obtained.

Furthermore, the Mooney viscosity [M L
(100°C)], 10 to 120, particularly 40 to 1+480. By using the copolymer rubber having a Mooney viscosity within this range, a thermoplastic elastomer molded article with excellent tensile properties can be obtained.

Furthermore, the iodine content (degree of unsaturation) of the above copolymer rubber is 1
It is preferably 6 or less.

In the present invention, the polyolefin resin and α-olefin copolymer rubber are usually 90/10 to 10/90,
Preferably, they are used in a weight ratio of 80/20 to 20/80 (polyolefin resin/α-olefin copolymer rubber).

The mixture powder containing the polyolefin resin and the a-olefin copolymer used in the present invention has a molecular weight of 20 to 40%.
0 mesh, preferably 42 to 200 mesh, more preferably 65 to 150 mesh, and can be obtained, for example, by the following method.

(+) Both polyolefin resin and α-olefin resin
A method in which a mixture with 6-body rubber is ground and mixed in an atmosphere of -60°C.

(2) A method of pulverizing and mixing a mixture of polyolefin resin powder taken out as powder during production or polyolefin resin powder obtained by freeze-pulverization and α-olefin copolymer rubber.

(3) The polyolefin resin powder in (2) above or the polyolefin resin powder obtained by freeze-pulverization and the α-olefin resin powder obtained by freeze-pulverization” (
1.4 Method of combining with polymer rubber powder.

In the present invention, the above polyolefin resin and α-
Mixture powder containing olefin copolymer rubber,
In the presence of a cross-linking agent, the powder mixture is placed in a mold for transferring a grain pattern and the mold is sealed, and then the mold is heated while being rotated so that the mixture powder adheres to the inner surface of the mold in a fluid plastic state. Then, the mold is cooled to form a textured pattern on the surface.
Thermoplastic elastomer molded products? However, during the above-mentioned melting, a crosslinking reaction is performed to produce a thermoplastic elastomer, and molding is performed simultaneously with the production.

Examples of the crosslinking agent used include organic peroxide, sulfur, phenolic vulcanizing agents, oximes, and polyamines. Among these, organic peroxide and Phenolic vulcanizing agents are preferred.

Particularly preferred is 9-mer peroxide.

As the phenolic vulcanizing agent, specifically, an alkylphenol formaldehyde resin, a triazine-formaldehyde resin, or a melamine-formaldehyde resin is used.

In addition, specific examples of the organic peroxide include dicumyl peroxide, di-tcrL-butyl peroxide,
2,5-dimethyl-2,5-bis(tart-butylperoxy)hexane, 2,5-dimethyl-2,5-bis(tart-butylperoxy)hexane-3,1,3
-Bis(LcrL-butylperoxyisopropyl)benzene, 1,1-bis(Lcrt-butylperoxy)
-3,3,5-1-limethylcyclohexane, n-butyl-4,4-bis(tart-butylperoxy)valerate, dibenzoyl peroxide, Lert-butylperoxybenzoate, etc. are used. Among these, dibenzoyl peroxide and l,3-bis(tart-butylperoxyisopropyl)benzene are preferred from the viewpoint of crosslinking reaction time, odor, and scorch stability.

In the present invention, the crosslinking agent is about 0.01-2 parts by weight, preferably 0.03-1. It is used in an amount of 0 parts by weight, more preferably 0.05 to 0.5 parts by weight.

Further, in order to achieve a uniform and moderate crosslinking reaction, it is preferable to include a crosslinking aid. Specific examples of crosslinking aids include sulfur, p-quinonedioxime, 1), +1-dibenzoylquinonedioxime, N-methyl-N, 4-dinitrosoaniline, nitrobenzene, diphenylguanidine, and trimethylolpropane. -N, N'-s-
Peroxy crosslinking aids such as phenylene dimaleimide, divinylbenzene, triallyl cyanurate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, trimethylolpropane trimethacrylate
! Polyfunctional methacrylate monomers such as allyl methacrylate, polyfunctional vinyl monomers such as vinyl butyrad or vinyl stearate, etc. are used. By using such a compound, a uniform and mild crosslinking reaction can be expected. In particular, divinylbenzene
It is easy to handle, has good compatibility with polymer particles, and has an organic peroxide solubilizing effect, which also acts as a peroxide dispersion aid, so the crosslinking reaction is homogeneous and improves fluidity and physical properties. A well-balanced thermoplastic elastomer molding? This is the most preferable because it allows you to

In the present invention, such a crosslinking auxiliary agent is used in an amount of 0.1 to 2 parts by weight, particularly 0.3 to 1 part by weight, based on 100 parts by weight of the above-mentioned polyolefin resin and α-olefin copolymer rubber. By blending within this range, a thermoplastic elastomer with excellent fluidity can be obtained, and the thermoplastic elastomer can be molded without deterioration of physical properties due to heat history during one-stroke molding. 111 things are done.

In the present invention, when producing a thermoplastic elastomer molded article, in addition to the above-mentioned mixture powder, crosslinking agent, and crosslinking aid, peroxide non-crosslinked hydrocarbon rubber typified by polyisobutylene, butyl rubber, etc. It is also possible to carry out the crosslinking reaction of the polyolefin resin and the α-olefin copolymer rubber in the presence of a substance and/or a mineral oil softener.

Mineral oil-based softeners usually weaken the intermolecular forces of rubber during roll processing, making processing easier.
A high boiling point petroleum distillate that is used to help disperse carbon black, white carbon, etc., or to reduce the hardness of vulcanized rubber and increase its flexibility or elasticity. , paraffinic, naphthenic,
Alternatively, aromatic mineral oil or the like may be used.

Such mineral oil-based softeners further improve the flow characteristics, ie, moldability, of thermoplastic elastomers.
Polyolefin resin and α-olefin J (total amount of polymer rubber: 31, 10 (,) @ 1 to part Q
]OO parts by weight, preferably 3 to 90 parts by weight, more preferably 5 to 80 parts by weight.

Further, a stabilizer may be added to the mixture powder or the mixture containing the mixture powder and the crosslinking agent used in the present invention. As such stabilizers, specifically, phenol stabilizers, phosphorus stabilizers, sulfur stabilizers, hindered amine stabilizers, higher fatty acid stabilizers, etc. are used.

The above stabilizers include polyolefin resins and a
- 0.00 parts per 100 parts by weight of olefin copolymer rubber. [11-10 parts by weight, preferably 0.05-10 parts by weight
Preferably, an amount of 5 parts by weight is used.

In addition, the mixture powder or the mixture containing the mixture powder and the crosslinking agent used in the present invention includes fillers such as calcium carbonate, calcium silicate, clay kaolin, talc, silica, diatomaceous earth, mica powder, asbestos,
Alumina, barium sulfate, aluminum sulfate, calcium sulfate, basic magnesium carbonate, molybdenum disulfide,
Graphite, glass fibers, glass bulbs, shirasu balloons, carbon fibers, or coloring agents such as carbon black, titanium oxide, zinc white, red iron, ultramarine blue, deep blue, azo dyeing, nitroso dyes, lake pigments, phthalocyanine pigments, etc. can also be blended. .

In the present invention, the expression that the grain pattern transfer mold is in a rotating heating state means that while the grain pattern transfer mold is being rotated,
For example, it refers to the state of heating with a heater. As described above, when the grain pattern transfer mold is in a rotational heating state, the powder of the polyolefin resin and α-olefin copolymer rubber in the sealed grain pattern transfer mold becomes fluid and plastic. The thermoplastic elastomer molded article is then melted in close contact with the inner surface of the mold for transferring the textured pattern, and a thermoplastic elastomer molded product having the textured pattern formed on the surface is obtained.

In the present invention, the polyolefin resin and α-olefin copolymer rubber powder penetrates deeply into the grains on the inner surface of the grain pattern transfer mold, which has fine irregularities, and forms the inner surface of the mold. Because of the close contact, 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, an example of a method for producing a textured thermoplastic elastomer molded article according to the present invention will be explained based on 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, a powder mixture containing the above-mentioned polyolefin resin and a-olefin resin is placed in the grain pattern transfer mold 1 in the presence of a crosslinking agent, and the mold 1 is sealed.

In the present invention, since the above-mentioned mixture powder is used, the shape of the mold 1 is not particularly limited, and molds of various shapes can be used, and deep drawn products can also be manufactured.

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

When heating the mold 1 while rotating, it may be heated under an atmosphere of an inert gas such as nitrogen or carbon dioxide.

The heating temperature is usually 150 to 210°C.

In the present invention, the mixture powder as described above is heated while rotating the grain pattern transfer mold 1 in the presence of a crosslinking agent, so that the mixture powder in the mold 1 becomes fluid and plastic. It penetrates deeply into the grain formed on the inner surface of the mold 1, and becomes dense blue and melts on the inner surface of the mold 1.

Therefore, in the present invention, a thermoplastic elastomer molded article with a deep grain pattern can be obtained.

In the present invention, a crosslinking reaction is performed during the melting to produce a thermoplastic elastomer, and molding is performed simultaneously with the production.

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.

Textured thermoplastic η obtained by the production method according to the present invention
Molded elastomer products have excellent scratch resistance, appearance, and texture. By applying this to a textured thermoplastic elastomer molded article, it is possible to obtain a thermoplastic elastomer molded article with a grain pattern that has even better scratch resistance, appearance, and texture.

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. It won't happen.

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 acid for forming the primer layer is molded according to a conventional method. Just apply it on the surface of the object.

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

Effects of the Invention The textured thermoplastic elastomer molded product according to the present invention has a textured pattern in which a mixture powder containing a polyolefin resin and an α-olefin copolymer rubber is rotated and heated in the presence of a crosslinking agent. By closely contacting and melting the inner surface of the transfer mold in a fluid plastic state, a textured pattern is formed on the surface. Compared to resin molded products, it has the effect that a grain pattern with a deeper grain depth can be formed, and also has the effect that mechanical properties do not deteriorate.

Furthermore, according to the production method of the present invention, the thermoplastic elastomer production process and its powdering process can be omitted, and 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.

In addition, the tensile properties, surface hardness, torsional rigidity, permanent elongation, heat aging properties, grain depth, soft feel, and gloss of the textured thermoplastic elastomer molded products obtained in the examples were evaluated by the following methods. . Samples for evaluation were punched out from the obtained molded product.

[Evaluation method] (1) Tensile properties According to JIS K-63 old method.

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

(3) Torsional rigidity ^ According to the method of STM 1043.

(4) Permanent elongation: According to JIS K-63 old 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 old JIS K-63 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...Normal 2...Hard 1...Very hard (8) Gloss Molded with grain according to JIS 28741 (specular gloss measurement method) Light on the surface of objects 6
Irradiation was performed at an incident angle of 0 degrees, and the reflectance was expressed in %.

Example 1 [Method for producing a mixture powder of polyolefin resin and α-olefin copolymer rubber] Using the following components, polyolefin resin and α-olefin copolymer rubber were prepared in the following manner. A mixture powder was prepared.

(Component A) Ethylene/propylene/ethylidenenorbornene ternary copolymer rubber; ethylene unit/propylene unit (molar ratio) +78/22, iodine value 15, Mooney viscosity (ML 1121°C) 1+4 6) (Component B) Polypropylene resin : Melt index (
^STM 01238, 230°C) 13 g/10 min, density 0.91 g/ci (Component C) Naphthenic process oil (Component A) 60 parts by weight, (Component B) 40 parts by weight, and (Component C) 25 parts by weight The mixture was kneaded in a Banbury mixer at 180° C. for 5 minutes under a nitrogen atmosphere, and the resulting kneaded product was cut into square pellets using a sheet cutter.

The thus obtained square pellets were ground in an atmosphere of -60°C to obtain a mixture powder of 42 to 100 meshes.

[Manufacture of molded product] First, a mold for a two-piece automobile dash board,
The following (component D) was added to a mold for transferring a grain pattern with a grain depth of 150 μm on the inner surface based on 100 parts by weight of the mixture powder of the polyolefin resin and α-olefin copolymer rubber. After mixing 1 part by weight in a Henschel mixer to a predetermined amount of powder mixture, the inside of the mold was placed under a nitrogen atmosphere.

(Component D) A mixture consisting of 40% by weight of 1,3-bis(Lert-butylperoxyisopropyl)benzene, 40% by weight of divinylbenzene, and 20% by weight of paraffinic mineral oil.

Next, while rotating this mold, the mold was heated to 210° C. from the outside of the mold using a heater to fluidize and melt the mixture powder inside the mold. During this time, 150℃
Heating was performed at 210° C. for 5 minutes and at 210° C. for 15 minutes.

Finally, this mold was water-cooled for 10 minutes to room temperature to obtain a thermoplastic elastomer molded article with a textured pattern.

The size of the obtained molded thermoplastic elastomer molded article with a textured pattern is 1200 mm long, 500 mm wide, and 1 mm thick.
It was 0+nm.

The resulting grained thermoplastic elastomer molded product was evaluated for tensile properties, surface hardness, torsional rigidity, permanent elongation, heat aging properties, grain depth, soft feel, and gloss using the methods described above.

The evaluation results are shown in Table 1.

Example 2 In Example 1, (component A) was 80! rfm part, (B
A molded product was obtained in the same manner as in Example 1, except that 20 parts by weight of component) and 10 parts by weight of butyl rubber (Esso +1R065) (component E) were added. The same evaluation was carried out.

The evaluation results are shown in Table 1.

Example 3 A molded product was obtained in the same manner as in Example 2, except that (component C) and (component E) were not used in Example 2, and the obtained molded product was evaluated in the same manner as in Example 2. I did it.

The evaluation results are shown in Table 1.

Example 4 In Example 1, powdered polypropylene resin (melt index 13) was used instead of (component B).
The same procedure as in Example 1 was carried out except that a density of 0.81 g/ci) was used.

The evaluation results are shown in Table 1.

Example 5 In Example 3, 42-1 obtained by separately pulverizing (component A) and (component B) in a -60°C atmosphere
[]0 mesh powder was mixed, and 100 weight part of this mixed powder was mixed with 1 part by weight of component D) in a Henschel mixer. This was done in the same manner as in 3.

The evaluation results are shown in Table 1.

[Brief explanation of 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. 1... Mold for grain pattern transfer 2... Heater

Claims (1)

[Scope of Claims] 1) A mixture powder containing a polyolefin resin and an α-olefin copolymer rubber is applied to the inner surface of a grain pattern transfer mold which is being heated in rotation in the presence of a crosslinking agent. 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 fluidized plastic state. 2) A mixture powder containing a polyolefin resin and an α-olefin copolymer rubber is placed in a grain pattern transfer mold in the presence of a crosslinking agent, and the mold is sealed. The mixture powder is melted while being rotated so that it adheres to the inner surface of the mold in a fluidized plastic state, 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 thermoplastic elastomer molded article.