JP3136740B2 - Thermoplastic elastomer powder composition for powder molding, powder molding method using the same, and molded article thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoplastic elastomer powder composition for powder molding, a powder molding method using the same, and a molded product thereof.

[0002]

2. Description of the Related Art A powder molded product of a vinyl chloride powder composition containing a plasticizer is used as a skin material for an automobile interior material, for example, an instrument panel, a console box, an armrest, a headrest, a door trim and the like. It is used. However, the molded article is not only inferior in light weight, but also generates an acidic substance by incineration at the time of end-of-life vehicle, causes air pollution, acid rain, etc., and is inferior in cleanliness. There are drawbacks derived from the plasticizer such as fogging on the inner surface of the window glass, which is not satisfactory.

The present inventors have studied to improve the disadvantages of such a vinyl chloride powder composition, and have already proposed an olefin-based thermoplastic elastomer powder for powder molding (Japanese Patent Application No. 3-199579). , Japanese Patent Application No. 3-199589). After that, when the investigation was continued, the thermoplastic elastomer powder showed good powder flowability immediately after pulverization, but the powders did not show the powder flowability necessary for powder molding due to aggregation of the powders during standing for a long time. The problem arose.

Further, when a powder slush molding method is carried out in which powders are thermally fused by bringing the powders into contact with a heated mold, and the powders not thermally fused are returned to a powder supply box. As a result of repeated execution of the powder that has not been fused, the powder is gradually warmed and accumulates heat in the powder supply box.As a result, the powders gradually agglomerate and the powder fluidity deteriorates. There has been a problem that a molded article having underfill and pinholes is produced.

Under such circumstances, the present inventors have conducted various studies on powder molding using a thermoplastic elastomer powder. As a result, the powder composition comprising the thermoplastic elastomer powder and a specific amount of fine powder was stored for a long period of time. In addition to finding that the powder composition exhibits good powder flowability, the use of the powder composition enables the production of a molded article free of underfill, pinholes and the like even when the powder slush molding method is continuously performed for a long time. The present inventors have found that the present invention can be performed, and have further studied variously to complete the present invention.

[0006]

That is, the present invention provides a thermoplastic elastomer powder of the following (A) containing 0.05 to 20 parts by weight of a fine powder having an average particle diameter of 30 μm or less based on 100 parts by weight. It is intended to provide a thermoplastic elastomer powder composition for powder molding, a powder molding method using the same, and a molded article thereof. (A) Powder of a thermoplastic elastomer comprising a composition of an ethylene / α-olefin-based copolymer rubber and a polyolefin-based resin or a partially crosslinked composition of an ethylene / α-olefin-based copolymer rubber and a polyolefin-based resin A thermoplastic elastomer powder consisting of 25
Complex dynamic viscosity η at a frequency of 1 radian / second at 0 ° C.
^* (1) is not more than 1.5 × 10 ⁵ poise, and the complex dynamic viscosity eta ^* (100) in the complex dynamic viscosity eta ^* (1) and the frequency of 100 rad / s and using the calculated by the following equation Thermoplastic elastomer powder having a Newtonian viscosity index n of 0.67 or less. n = {logη ^* (1) −logη ^* (100)} / 2

The present invention also provides a powder molding method using the above-mentioned thermoplastic elastomer powder composition for powder molding, and a molded article produced by using the above-mentioned thermoplastic elastomer powder composition for powder molding.

Hereinafter, the present invention will be described in detail. Examples of the ethylene / α-olefin copolymer rubber used in the present invention include rubbers containing olefin as a main component such as ethylene / propylene copolymer rubber and ethylene / propylene / non-conjugated diene copolymer rubber. . Examples of the non-conjugated diene include dicyclopentadiene, ethylidene norbornene, 1,4-hexadiene, cyclooctadiene, and methylene norbornene. Among them, ethylene-propylene-ethylidene norbornene rubber (hereinafter referred to as EPDM) is preferable, and a molded article excellent in heat resistance, tensile properties, and the like can be obtained by using this.

The Mooney viscosity of the ethylene / α-olefin copolymer rubber (the Mooney viscosity (ML _{1 + 4} 100 ° C.) measured at 100 ° C. according to ASTM D-927-57T) is usually 130 or more and 350 or less. Preferably it is 200 or more and 300 or less. It is also preferable to use an oil-extended olefin-based copolymer rubber obtained by adding a mineral oil-based softener such as a paraffin-based process oil to an ethylene / α-olefin-based copolymer rubber. Not only is it improved, but also the flexibility of the molded body is improved. The content of the mineral oil-based softening agent is usually 30 to 120 parts by weight per 100 parts by weight of the ethylene / α-olefin copolymer rubber.

As the polyolefin resin, polypropylene, a copolymer of propylene and ethylene, and a copolymer of propylene and an α-olefin other than propylene are preferably used. In particular, by using a copolymer resin of propylene and butene, the hardness of the molded article can be reduced. If the melt flow rate of the polyolefin resin (MFR, JIS K-7210, measured at 230 ° C, 2.16 kg load) is less than 20 g / 10 minutes, the powders are less likely to melt and adhere during powder molding. Since the strength of the body is reduced, usually, those having a weight of 20 g / 10 min or more are used. It is preferably at least 50 g / 10 minutes.

The thermoplastic elastomer of the present invention comprises:
A composition of the above-mentioned ethylene / α-olefin-based copolymer rubber and polyolefin-based resin, or a partially cross-linked composition obtained by dynamically cross-linking this composition.
-The ratio between the olefin copolymer rubber and the olefin resin is preferably usually 5:95 to 80:20 by weight. In performing dynamic crosslinking, an organic peroxide is generally used as a crosslinking agent. As organic peroxides,
Dialkyl peroxide is preferably used. In addition, it is preferable to dynamically crosslink using a very small amount of an organic peroxide in the presence of a crosslinking assistant such as a bismaleimide compound. In this case, the ethylene / α-olefin copolymer rubber is appropriately crosslinked and heat resistant. At the same time, high fluidity can be realized. The crosslinking agent is used in an amount of 1.5 parts by weight or less, preferably 0.6 parts by weight or less, per 100 parts by weight of the composition of the ethylene / α-olefin copolymer rubber and the polyolefin resin, and the organic peroxide is 0.2 parts by weight. The amount is preferably 0.1 part by weight or less, more preferably 0.07 part by weight or less.

As a device used for dynamic crosslinking, a continuous kneading extruder such as a single screw kneading extruder or a twin screw kneading extruder is preferably used. In the case of using a twin-screw kneading extruder, if the extrusion crosslinking is performed at a shear rate of <10 ³ sec ^-1 , ethylene-α-
Since the dispersion particle size of the olefin copolymer rubber becomes large and it becomes difficult to realize the viscosity condition of the present invention, it is preferable to carry out continuous extrusion crosslinking at a shear rate of 10 ³ sec ^-1 . The thermoplastic elastomer according to the present invention has a temperature of 250 ° C.
Complex dynamic viscosity η ^* measured at a frequency of 1 radian / second (1)
Is 1.5 × 10 ⁵ poise or less, preferably 1.0 × 10 ⁵ poise or less. If it exceeds 1.5 × 10 ⁵ poise, the powder of the elastomer does not melt and flow on the mold surface, and cannot be molded by a powder molding method having a very low shear rate of 1 sec ⁻¹ or less during processing.

Further, using the complex dynamic viscosity η ^* (1) measured at 250 ° C. and a frequency of 1 radian / sec and the complex dynamic viscosity η ^* (100) measured at a frequency of 100 radian / sec, the following equation is used. The calculated Newtonian viscosity index n is 0.67 or less, preferably
0.60 or less. n = {logη ^* (1) −logη ^* (100))} / 2 If the Newton viscosity index n exceeds 0.67, the frequency 1
Complex dynamic viscosity η ^* (1) measured in radians / second is 1.5 ×
Even if it is less than 10 ⁵ poise, the frequency dependence of the complex dynamic viscosity becomes large, and the molding pressure during molding is very small, such as 1 kg / cm ² or less. The heat fusion between them becomes incomplete and only a molded article having low mechanical properties can be obtained.

The thermoplastic elastomer composition used in the present invention is obtained by blending not more than 50 parts by weight of an uncrosslinked ethylene-α-olefin copolymer rubber or ethylene-α-olefin copolymer resin with respect to 100 parts by weight of the elastomer. To improve the flexibility of the molded article. In this case, as the α-olefin, propylene, butene, or the like is used alone or in combination. In particular, an ethylene-propylene copolymer rubber having an ethylene content of 40 to 90% by weight, preferably 70 to 85% by weight and having an ML _{1 + 4} 100 ° C. of 50 or less is preferred. Thermoplastic elastomer powder is
The thermoplastic elastomer composition is produced by pulverizing the above-mentioned thermoplastic elastomer composition at a low temperature, for example, lower than the glass transition temperature. The average particle system is usually between 100 μm and 300 μm.

[0015] The thermoplastic elastomer powder composition of the present invention is characterized by comprising the above-mentioned thermoplastic elastomer powder and a specific amount of fine powder. The diameter is 30μm or less,
More preferably, those having a diameter of 0.1 to 10 μm are used.
Here, if the average particle diameter exceeds 30 μm, good powder fluidity cannot be maintained during long-term storage. Such fine powders include, for example, azo-based, phthalocyanine-based, sulene-based, organic pigments such as dye lakes, oxides such as titanium oxide, molybdic acid chromate, selenium sulfide compounds, ferrocyanide And inorganic pigments such as carbon black, vinyl chloride resin for paste, powders of aluminum oxide, aluminum hydroxide, calcium carbonate and the like. Above all, the pigment is preferable because a small amount of the pigment keeps good powder fluidity and at the same time colors the molded body, so that the subsequent coloring step can be omitted.

The content of the fine powder is from 0.05 to 20 parts by weight, preferably from 0.1 to 8 parts by weight, more preferably from 0.1 to 4 parts by weight, based on 100 parts by weight of the thermoplastic elastomer powder. is there. If the content is less than 0.05 parts by weight,
It is difficult to maintain good powder fluidity during long-term storage,
If the amount exceeds 20 parts by weight, a molded article having a sufficiently high heat fusion strength between powder particles cannot be obtained.

The method for incorporating the fine powder into the thermoplastic elastomer powder is not particularly limited as long as the fine powder is uniformly dispersed. For example, a blender with a heating jacket or a high-speed rotating A method of blending using a mold mixer or the like can be used. Among them, a method of applying a shearing force, such as a super mixer, to prevent cohesion of powder and uniformly disperse the powder is preferable. Also, the powder may be added while heating within a range where the powders are not thermally fused.

Further, the elastomer powder composition of the present invention may contain an internally added release agent. As the internally added release agent, a methylpolysiloxane compound is preferable, and it is effective to contain 2 parts by weight or less per 100 parts by weight of the elastomer powder composition. In this case, the timing of addition may be before or after powdering. In this case, the methylpolysiloxane compound may have a viscosity at 25 ° C. of 20 centistokes or more, but is preferably 50 to 50.
00 centistokes. If the viscosity is too high, the effect as a release agent is reduced. If the amount of the internally added release agent exceeds 2 parts by weight, heat fusion between the elastomer powders is hindered, and only a molded article having poor mechanical properties is obtained. Bleed, and the mold is undesirably contaminated.

Further, the elastomer powder composition of the present invention may contain a known heat stabilizer such as a phenol-based, sulfite-based, phenylalkane-based, phosphite-based, amine-based or amide-based stabilizer, an antioxidant, and a weather-resistant stabilizer. Agents, antistatic agents, lubricants such as metallic soaps and waxes, coloring pigments and the like can be contained in necessary amounts. Such an elastomer powder composition is not only excellent in powder flowability, but also can be easily melted by heat supplied from a mold under a low shear rate and a low pressure.
It is excellent as a composition for molding methods such as electrostatic coating, powder spraying, powder rotation molding, and powder slush molding, and is particularly excellent as a composition for powder slush molding method (JP-A-58-132507). I have. In powder molding, the heating method of the mold is not particularly limited, for example,
Examples thereof include a gas heating furnace method, a heating medium oil circulation method, a dipping method in heating medium oil or hot fluidized sand, and a high-frequency induction heating method.

[0020]

Industrial Applicability The elastomer powder composition of the present invention exhibits excellent powder fluidity even when stored for a long period of time. Furthermore,
When the powder composition is used, not only can a molded article having a uniform thickness and no pinholes be produced even if powder molding is performed continuously for a long time, and a molded article excellent in lightness and cleanness can be obtained. Can be manufactured. In addition, the molded article of the present invention can be used as a covering material for, for example, home appliances, office supplies, chairs, furniture, and the like, and particularly, a covering material for instrument panel skins of automobiles, console boxes, armrests, and door trims.

[0021]

Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. The dynamic viscoelasticity, powder properties and moldability of the thermoplastic elastomer powder compositions and powders in the examples and comparative examples were determined by the following methods.

Dynamic Viscoelasticity of Thermoplastic Elastomer Composition Dynamic Analyzer DRS-77 manufactured by Rheometrics.
Using model 00, the dynamic viscoelasticity was measured at an oscillation frequency of 1 radian / sec and 100 radian / sec, and the complex dynamic viscosity η ^* (1)
And η ^* (100) were calculated. The measurement was performed in a parallel plate mode, the applied strain was 5%, and the sample temperature was 250 ° C. Further, based on the results of η ^* (1) and η ^* (100), the Newtonian viscosity index n was calculated by the following equation. n = {logη ^* (1) −logη ^* (100)} / 2

The powder composition was allowed to stand for one month in an atmosphere of 25 ° C. 100ml of the elastomer powder composition is JIS
K-6721 was placed in the funnel of the bulk specific gravity measuring device, the damper was pulled out, and the time (number of seconds) from when the powder started to fall until all the powder finished falling was measured. The shorter the time, the better the powder fluidity.

Blocking property Under an atmosphere of 25 ° C., 500 kg /
It was left for 1 month under a pressure of m ² . The powder composition was gently transferred to a 32 mesh Tyler standard sieve and shaken for 10 seconds to calculate the weight% of the powder remaining on the 32 mesh sieve. The smaller the weight percentage is, the less the blocking is likely to occur in the elastomer powder composition.

Powder moldability (powder moldability) 500 g of the elastomer powder composition was treated at a surface temperature of 250 ° C.
Spread over a nickel electroformed grain plate having a size of 30 cm × 30 cm and a thickness of 3 mm, which has been heated, and allowed to adhere for 14 seconds. In a heating furnace for 60 seconds. The fusion state of the powder on the mold and the mold
The powder moldability was evaluated based on the following criteria from the properties of the molded sheet obtained by demolding after water-cooling to ℃. A: The powder compositions are sufficiently fused with each other, and the obtained molded sheet has sufficiently high tensile strength. ：: The powder compositions are sufficiently fused with each other, and the obtained molded sheet has a high tensile strength. Δ: The powder compositions fuse with each other, but the obtained molded sheet has low tensile strength and is brittle. X: The powder compositions do not fuse with each other and exist on the mold as they are. ◎ and ○ can be processed to the final product, but △ and × cannot be processed to the final product.

Reference Example 1 EPDM (ML _{1 + 4} 100 ° C. = 242, propylene content = 28
Weight%, iodine value = 12) 100 parts by weight of mineral oil based softener (manufactured by Idemitsu Kosan, registered trademark Diana Process PW プ ロ セ ス 380)
) 100 parts by weight of oil-extended EPDM (ML _{1 + 4} 100
C = 53) 40 parts by weight and a propylene / butene random copolymer resin (butene content = 24% by weight, MFR = 90 g / 10
60 parts by weight and 0.4 parts by weight of a crosslinking assistant (Sumitomo Chemical Co., Ltd., Sumifine BM @ bismaleimide compound) are kneaded for 10 minutes using a Banbury mixer, and then pelletized for crosslinking using an extruder. Master batch (hereinafter referred to as M.B.
B. ). This M. B. To 100 parts by weight, 0.04 parts by weight of an organic peroxide (manufactured by Sanken Kako Co., Ltd., Samperox APO, 2,5-dimethyl-2,5-di (t-butylperoxyno) hexane) was added. Dynamic cross-linking was performed at 220 ° C. using a shaft kneader (trade name: TEX # 44, manufactured by Nippon Steel Works) to obtain elastomer composition pellets.
After cooling the pellets to a temperature of -100 ° C. using liquid nitrogen, the pellets are frozen and pulverized to obtain a complex dynamic viscosity η ^* (1) of 7 × 10 ³
A thermoplastic elastomer powder having a Poise and Newton viscosity index n of 0.39 was obtained.

Example 1 The thermoplastic elastomer powder 100 obtained in Reference Example 1
0.1 parts by weight of black pigment (PV # 817 manufactured by Sumika Color Co., Ltd., average particle size 0.02 μm) is added to 25 parts by weight using a super mixer.
The mixture was kneaded at 500 ° C. and 500 rpm for 10 minutes to obtain a thermoplastic elastomer powder composition for powder molding. Using this composition, powder properties and moldability were evaluated. Table 1 shows the evaluation results.

Example 2 A thermoplastic elastomer powder composition for powder molding was obtained in the same manner as in Example 1, except that the addition amount of the black pigment was changed to 1.5 parts by weight. Table 1 shows the evaluation results.

Example 3 A thermoplastic elastomer powder composition for powder molding was obtained in the same manner as in Example 1 except that the amount of the black pigment was changed to 10 parts by weight. Table 1 shows the evaluation results.

Example 4 The same procedure as in Example 2 was carried out except that the black pigment was replaced with a red pigment (manufactured by Sumika Color, PV # 110, average particle size 0.18 μm). A thermoplastic elastomer powder composition was obtained. Table 1 shows the evaluation results.

Example 5 The same procedure as in Example 2 was carried out except that the black pigment was replaced with a yellow pigment (PV # 354 manufactured by Sumika Color, average particle size 0.13 μm). A thermoplastic elastomer powder composition was obtained. Table 1 shows the evaluation results.

Example 6 The same procedure as in Example 2 was carried out except that the black pigment was replaced with a white pigment (PV # 742 manufactured by Sumika Color, average particle diameter 0.2 μm). A thermoplastic elastomer powder composition was obtained. Table 1 shows the evaluation results.

Example 7 The procedure of Example 2 was repeated except that the black pigment was changed to aluminum oxide (AM-21, manufactured by Sumitomo Chemical Co., Ltd., average particle diameter: 5 μm).
In the same manner as in Example 2, a thermoplastic elastomer powder composition for powder molding was obtained. Table 1 shows the evaluation results.

Example 8 The procedure of Example 2 was repeated except that the black pigment was changed to aluminum oxide (AES-12, manufactured by Sumitomo Chemical Co., Ltd., average particle size: 0.4 μm). A plastic elastomer powder composition was obtained. Table 1 shows the evaluation results.

Example 9 The procedure of Example 2 was repeated, except that the black pigment was replaced with vinyl chloride for paste (PxQLT manufactured by Sumitomo Chemical, average particle size 1.2 μm). A plastic elastomer powder composition was obtained. Table 1 shows the evaluation results.

Example 10 The procedure of Example 2 was repeated except that the black pigment was replaced with vinyl chloride for paste (manufactured by Sumitomo Chemical Co., Ltd., average particle size 0.08 μm).
In the same manner as in Example 2, a thermoplastic elastomer powder composition for powder molding was obtained. Table 1 shows the evaluation results.

Comparative Example 1 A thermoplastic elastomer powder composition was obtained in the same manner as in Example 1, except that no black pigment was used. Table 1 shows the evaluation results.

Comparative Example 2 The procedure of Example 1 was repeated except that 25 parts by weight of the black pigment was used.
In the same manner as in Example 1, a thermoplastic elastomer powder composition was obtained. Table 1 shows the evaluation results.

Comparative Example 3 A thermoplastic elastomer powder composition was prepared in the same manner as in Example 2 except that the black pigment was changed to aluminum oxide (A-21, manufactured by Sumitomo Chemical Co., Ltd., average particle size: 50 μm). I got Table 1 shows the evaluation results.

Examples 11 to 16 The procedure of Example 1 was repeated, except that the black pigment was used in parts by weight shown in Table 2, to obtain a thermoplastic elastomer powder composition for powder molding. Table 2 shows the evaluation results.

Comparative Example 4 In Reference Example 1, 70 parts by weight of oil-extended EPDM was used, and the propylene / butene random copolymer resin was changed to a propylene / ethylene random copolymer resin (ethylene content = 3% by weight, MFR = 1.2 g / (10 minutes) A thermoplastic elastomer powder was obtained in the same manner as in Reference Example 1 except that the amount was changed to 30 parts by weight. This product had η ^* (1) of 1.9 × 10 ⁵ poise and Newton's viscosity index n of 0.69. Next, using this, it carried out similarly to Example 1 and obtained the thermoplastic elastomer powder composition. The results are shown in Table 2.

Example 17 In Example 1, 0.22 parts by weight of a black pigment, 0.53 parts by weight of a red pigment (PV-110, manufactured by Sumika Color Co.), and 1.15 parts by weight of a yellow pigment (PV-354, manufactured by Sumika Color Co.) Example 1 except that 0.05 parts by weight of a white pigment (PV-742 manufactured by Sumika Color Co., Ltd.) was used.
In the same manner as described above, a thermoplastic elastomer powder composition for powder molding was obtained. The results are shown in Table 3.

Examples 18 to 19 Each of the thermoplastic elastomer powder compositions produced in the same manner as in Example 17 was allowed to stand in a gear oven at 40 ° C. and 60 ° C. for 8 hours. The evaluation was performed, and the results are shown in Table 3.

Example 20 4 kg of the thermoplastic elastomer powder composition obtained in Example 2 was put into a stainless steel rectangular container (powder supply box) shown in FIGS. This square container is 600mm
It has a rectangular opening 1 of × 220 mm, a depth of 210 mm, and is attached to the uniaxial rotating device 3. On the other hand, the nickel electroforming mold shown in FIGS. 4 to 6 having the opening 1 of the powder supply box shown in FIG. 1 and the opening 4 having the same size was preheated in a gas furnace at 300 ° C. This mold has a thickness of 3 mm, and has a complicated shape in which an inner surface is provided with a wrinkle pattern 5 and a grain pattern 6. As soon as the surface temperature of the mold reaches 250 ° C., the heated mold is placed in such a manner that the opening 4 (600 mm × 220 mm) faces downward, and is aligned with the opening 1 of the powder supply box. The outer frame attached around the opening was tightly attached, fixed with the clip 2 and integrated. Immediately two revolutions clockwise at a speed of 30 revolutions per minute and two revolutions counterclockwise at a speed of 30 revolutions per minute. Then, one clockwise and one counterclockwise
Each time it was swung to an angle of about 120 degrees, and excess powder adhering to the complicated shape portion was wiped off.

With the opening 4 of the mold facing downward, the rotation and swing operations are stopped, and the mold is removed from the powder supply box.
After heating for one minute in a heating furnace at 280 ° C., the resultant was cooled with water and the molded film was removed from the mold. The molded film has a weight of 150 g and a thickness of 0.9.
Up to 1.1mm without underfill, faithful reproduction of line patterns and grain patterns, and reproduction of complex molds with sufficient pin thickness and uniformity Was done.

In the container, 3.8 kg of an elastomer powder composition free of foreign matter was recovered. Unused elastomer powder composition was added to this recovered elastomer powder composition to make it 4 kg, and molding was performed by the same operation. As a result, a product excellent in appearance and thickness uniformity was similarly obtained.

[0047]

[0048]

[0049]

[Brief description of the drawings]

FIG. 1 is a plan view of a powder supply box.

FIG. 2 is an elevation view of a powder supply box.

FIG. 3 is a side view of the powder supply box.

FIG. 4 is a plan view of a mold.

FIG. 5 is an elevation view of a mold.

FIG. 6 is a side view of a mold.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Opening 2 ... Clip 3 ... Uniaxial rotation device (handle) 4 ... Opening 5 ... Wrinkle pattern part in a mold 6 ... Mold inner grain pattern part

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Tadashi Hikasa 5-1, Anesaki Beach, Ichihara City, Chiba Prefecture Within Sumitomo Chemical Industries Co., Ltd. (72) Inventor Hiroaki Tsumori 5-1, Anesaki Beach, Ichihara City, Chiba Prefecture Sumitomo Chemical Co., Ltd. (56) References JP-A-5-5050 (JP, A) JP-A-5-1183 (JP, A) JP-A-2-57309 (JP, A) JP-A-57-125232 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) C08J 3/00-3/28 C08L 1/00-101/16

Claims (4)

(57) [Claims] 1. A thermoplastic elastomer powder for powder molding, which comprises 0.05 to 20 parts by weight of a fine powder having an average particle diameter of 30 μm or less based on 100 parts by weight of a thermoplastic elastomer powder of the following (A). Composition. (A) Powder of a thermoplastic elastomer comprising a composition of an ethylene / α-olefin-based copolymer rubber and a polyolefin-based resin or a partially crosslinked composition of an ethylene / α-olefin-based copolymer rubber and a polyolefin-based resin A thermoplastic elastomer powder consisting of 25
Complex dynamic viscosity η at a frequency of 1 radian / second at 0 ° C.
^* (1) is not more than 1.5 × 10 ⁵ poise, and the complex dynamic viscosity eta ^* (100) in the complex dynamic viscosity eta ^* (1) and the frequency of 100 rad / s and using the calculated by the following equation Thermoplastic elastomer powder having a Newtonian viscosity index n of 0.67 or less. n = {logη ^* (1) −logη ^* (100)} / 2 2. The composition according to claim 1, wherein the fine powder is at least one kind of fine powder selected from pigment, vinyl chloride resin aluminum oxide, aluminum hydroxide and calcium carbonate. 3. A powder molding method comprising using the thermoplastic elastomer powder composition for powder molding according to claim 1. 4. A molded article produced by using the thermoplastic elastomer powder composition for powder molding according to claim 1.