JPH0890723A - Interior part for car - Google Patents

Abstract

PURPOSE: To provide an interior part for a car not requiring surface treatment such as painting and having an elastomer skin. CONSTITUTION: An interior part for a car is constituted of an olefinic resin base material with bending modulus of 10,000kg/cm<2> or more and a skin with JIS-A hardness of 50-95 and an average wall thickness of 1.5-3mm formed from a styrenic thermoplastic elastomer wherein styrene/conjugated diene block copolymers (A), (B), (C) respectively having wt. average mol.wts. of 150,000-300,000, 100,000-150,000 and 50,000-100,000 are compounded so that the ratio of A:B:C is 1-6:1-6:1-6 and A+B+C is 10 and paraffinic oil (D) is compounded in a ratio of 60-20wt.% with respect to 40-80wt.% of the sum total of (A) (C) and 10-60 pts.wt. of a polypropylene resin (E) and 1-40 pts.wt. of a polyethylene resin (F) with density of 0.940g/cm<3> or less are compounded with respect to 100 pts.wt. of the sum total of (A)-(D).

Description

Detailed Description of the Invention

[0001]

The present invention can be used without coating,
The present invention relates to an automobile interior part having an elastomer skin.
More specifically, the present invention relates to an automobile interior part having an elastomer skin, which has a low gloss, a soft feeling, a non-sticky surface, and an excellent injection molding appearance.

[0002]

2. Description of the Related Art Conventional automobile interior parts are made of a single layer molded product of polypropylene, polyvinyl chloride (PV) molded by a laminating method, a slush method, an injection molding method, or the like.
C) It was a molded product with the sheet as the skin. However, a polypropylene single-layer molded product is inferior in softness, and P
In the case of a molded product using a VC sheet as the skin, a combination of numerous processes such as sheet forming, embossing vacuum forming, and pasting is required, resulting in low production efficiency, poor material yield, and difficulty in recycling. I had a problem.

As one of the attempts to solve these problems, a molded article using a hard thermoplastic resin as a base material and a thermoplastic elastomer as a surface layer material has already been put to practical use as an interior part for automobiles. There is. Such conventional automobile interior parts are roughly formed by the following two methods. (1) A method in which the skin (elastomer) is formed into a sheet shape in advance, and then various molding methods such as stamping molding (flow stamping) and insert molding are used. (2) Molding method of molding the skin itself by injection (two-color (layer) molding method, insert molding method, sandwich molding method).

[0004]

However, the interior parts for automobiles constructed in this manner all have a stickiness peculiar to the elastomer, and as a result, dust is likely to adhere and it is difficult to remove dust. There is a problem that the elastomer is easily scratched. In addition to this, when a thermoplastic elastomer is used as the surface layer material, gloss,
The molding appearance etc. becomes a problem.

For this reason, most of conventional automobile interior parts having an outer skin made of an elastomer are surface-coated. As a result, the number of processes is increased, which causes problems such as a decrease in yield and an increase in production cost. In particular, in the molding method of (2) above, the product itself must be coated or painted, which not only significantly increases the cost but also requires a soft paint to convey the elasticity of the elastomer to the surface. However, since the paint is limited and most of them are composed of the primer and urethane paint, the coating film becomes thick and the transferability such as wrinkles is deteriorated.

An object of the present invention is to provide an injection-molded interior part for an automobile, which does not require surface treatment such as painting and which has an elastomeric skin excellent in touch and gloss and having a soft appearance. Is.

[0007]

The inventors of the present invention have conducted extensive studies to solve the above-mentioned problems, and as a result, have found that a styrene-based thermoplastic elastomer component having a specific weight average molecular weight and a specific resin can be used. By forming the skin (surface layer) from materials that have been mixed with the specified components in a specific ratio, it is possible to obtain interior parts for automobiles that have low gloss, have a soft feeling, are not sticky on the surface, and have an excellent injection-molded appearance. The present invention has been completed and the present invention has been completed.

That is, the present invention has a flexural modulus of 10,
The JIS-A hardness is 50 to 95, which is formed from an olefin resin base material of 000 kg / cm ² or more and a styrene thermoplastic elastomer in which specific components are mixed in a specific ratio.
And an outer skin having an average wall thickness of 1.5 to 3 mm. In the automobile interior part of the present invention, the skin is bonded to the base material by fusion bonding.

The specific components forming the skin of the automobile interior part of the present invention are the following components (A) to (F). (A) Weight average molecular weight 150,000 to 300,000
Hydrogenated products of styrene / conjugated diene block copolymers. (B) Weight average molecular weight 100,000 to 150,000
Hydrogenated products of less than styrene / conjugated diene block copolymer. (C) A hydrogenated product of a styrene / conjugated diene block copolymer having a weight average molecular weight of 50,000 to less than 100,000. (D) Paraffin oil. (E) Polypropylene resin. (F) A polyethylene resin having a density of 0.940 g / cm ³ or less.

In the present invention, these components are blended in the following proportions to form a thermoplastic elastomer for the skin. That is, the components (A) to (C) are replaced by A: B: C =
(1-6): (1-6): (1-6) and A + B +
The components are blended at a component ratio of C = 10, and the blending ratio of the component (D) to the total of 40 to 80% by weight of these components (A) to (C) is 60 to 20% by weight, and these components are With respect to 100 parts by weight in total of (A) to (D),
10 to 60 parts by weight of component (E) and 1 to 40 of component (F)
Add parts by weight.

The "weight average molecular weight" in this specification is the polystyrene equivalent weight average molecular weight measured by gel permeation chromatography (GPC) under the following conditions.・ Measurement equipment: 150C ALC / GPC (MILLIPORE) ・ Column: AD80M / S (Showa Denko KK) 3 tubes ・ Solvent: o-dichlorobenzene ・ Temperature: 140 ° C ・ Flow rate: 1 ml / min・ Injection amount: 200 μl ・ Concentration: 2 mg / ml (antioxidant 2,6-di-t
Add 0.2% by weight of butyl-p-phenol. Concentration detection is measured with an infrared spectrophotometer MIRAN1A manufactured by FOXBORO at a wavelength of 3.42 μm. )

Next, each of the above components will be individually described in detail. The component (A) used in the present invention is a hydrogenated product of a styrene / conjugated diene block copolymer having a weight average molecular weight of 150,000 to 300,000. As a hydrogenated product of this styrene / conjugated diene block copolymer,
Styrene / ethylene / butylene / styrene copolymer (hereinafter sometimes simply abbreviated as "SEBS") which is a hydrogenated product of styrene / butadiene block copolymer, or hydrogenated product of styrene / isoprene block copolymer And a hydrogenated product of a styrene / isoprene / butadiene block copolymer, or a styrene / ethylene / propylene / styrene copolymer (hereinafter sometimes simply referred to as “SEPS”).

The hydrogenated products of these styrene / conjugated diene block copolymers have a styrene content of 5 to 50% by weight, preferably 8 to 45% by weight, particularly preferably 10 to
It is important to use a block copolymer having 40% by weight and a hydrogenation rate of 95% or more.

The hydrogenated products of these styrene / conjugated diene block copolymers can be produced, for example, by the method described in JP-B-40-23798, using a lithium catalyst or the like in an inert solvent. A styrene / butadiene block copolymer was synthesized and then described in, for example, JP-B-42-8704, JP-B-43-6636, JP-A-59-133203, and JP-A-60-79005. Depending on the method, a method of hydrogenating in the presence of a hydrogenation catalyst in an inert solvent can be mentioned.

The weight average molecular weight of the hydrogenated product of the styrene / conjugated diene block copolymer of the component (A) is 300,0.
When it exceeds 00, the moldability becomes poor.

The component (B) used in the present invention is a hydrogenated product of a styrene / conjugated diene block copolymer having a weight average molecular weight of 100,000 to less than 150,000.
Typical examples of the hydrogenated product of the styrene / conjugated diene block copolymer are SEBS, SEPS, and hydrogenated products of the styrene / isoprene / butadiene block copolymer.

The hydrogenated product of these styrene / conjugated diene block copolymers has a styrene content of 5 to 50% by weight, preferably 8 to 45% by weight, particularly preferably 10 to
It is important to use a block copolymer having 40% by weight and a hydrogenation rate of 95% or more. Further, the hydrogenated product of the styrene / conjugated diene block copolymer as the component (B) can also be produced by the same method as the above-mentioned method for producing the component (A).

The component (C) used in the present invention is a hydrogenated product of a styrene / conjugated diene block copolymer having a weight average molecular weight of 50,000 to less than 100,000. Typical examples of hydrogenated products of this styrene-conjugated diene block copolymer are SEBS, SEPS, or styrene
It is a hydrogenated product of an isoprene-butadiene block copolymer.

The hydrogenated products of these styrene / conjugated diene block copolymers have a styrene content of 5 to 50% by weight, preferably 8 to 45% by weight, particularly preferably 10 to
It is important to use a block copolymer having 40% by weight and a hydrogenation rate of 95% or more. Further, the hydrogenated product of the styrene / conjugated diene block copolymer as the component (C) can also be produced by the same method as the above-mentioned method for producing the component (A).

The hydrogenated product of the styrene / conjugated diene block copolymer as the component (C) has a weight average molecular weight of 50,000.
When it is less than 0, the molded product is inferior in rubber elasticity and mechanical strength.

The paraffinic oil of component (D) used in the present invention has a kinematic viscosity at 40 ° C. of 20 to 800 cS.
t, preferably 50 to 600 cSt, pour point 0 to -4
0 ° C, preferably 0--30 ° C, and flash point (CO
C) is 200 to 400 ° C, preferably 250 to 350 ° C
The oil of is preferably used.

The oil is generally a mixture of three aromatic rings, naphthene rings and paraffin chains,
Paraffin chain carbon number occupies 50% or more of the total carbon number, and paraffinic oil, naphthene ring carbon number 30 to 4
Those having 5% are called naphthenic oils, and those having more than 30% aromatic carbons are called aromatic oils. If an oil other than the paraffinic oil is used, the remarkable effect of the present invention cannot be obtained.

The component (E) used in the present invention is a polypropylene resin. Specifically, the melt flow rate (M
FR) (JIS K 6758, 230 ° C, 2.16k
g load) is 0.01 to 80 g / 10 minutes, preferably 0.
1 to 70 g / 10 minutes, particularly preferably 0.5 to 50 g /
A crystalline polypropylene resin having an ethylene content of 0 to 15% by weight, preferably 1 to 13% by weight, particularly preferably 2 to 10% by weight in 10 minutes.

When a component having a melt flow rate less than the above range is used as the component (E), the injection moldability is deteriorated,
The appearance of the obtained injection-molded article is deteriorated, and particularly, the generation of flow marks becomes remarkable. When a melt flow rate exceeding the above range is used, the material strength is lowered. Also,
If the ethylene content exceeds the above range, the heat resistance deteriorates. The ethylene content here is a value measured by an infrared spectrum analysis method or the like.

The component (F) polyethylene resin used in the present invention is manufactured by a conventional method and has a density of 0.9.
40 g / cm ³ or less, preferably 0.939 g / cm ³
The polyethylene resin having 0.938 g / cm ³ or less is particularly preferable.

Examples of such a polyethylene resin include a low density polyethylene resin obtained by the high pressure method and a low density and medium density polyethylene resin which is a copolymer of ethylene and α-olefin obtained by the medium and low pressure method. As the linear α-olefin which is a comonomer, butene-
1, pentene-1, hexene-1,4-methylpentene-1, octene-1, etc. may be mentioned, and two or more of them may be used in combination. As a manufacturing method, pressure 5 to 2,500k
A method of copolymerizing ethylene and an α-olefin under a condition of g / cm ² and a temperature of 50 to 300 ° C. using a catalyst such as a Ziegler type catalyst, a vanadium type catalyst, a Kaminsky type catalyst and the like is adopted. For example, the method disclosed in Japanese Patent Publication No. 56-18132 is known.

Of these, polyethylene resins obtained by the high pressure method are particularly preferable. If a density exceeding the above range is used, the appearance of the obtained injection-molded product deteriorates (roughness of the surface, generation of flow marks, etc.).

In addition to the above-mentioned essential components, the styrene-based thermoplastic elastomer of the present invention may be blended with other components in accordance with various purposes within a range that does not significantly impair the effects of the present invention. In particular, since the interior parts for automobiles of the present invention are used without being painted, it is essential to unify the colors with other interior parts (color matching), and thus the colorant is an important component.

As the optional component, for example, an antioxidant,
Heat stabilizer, light stabilizer, ultraviolet absorber, neutralizer, lubricant, lubricant, antifogging agent, antiblocking agent, slip agent, dispersant, flame retardant, antistatic agent, conductivity imparting agent, crosslinking agent, Examples include metal deactivators, molecular weight regulators, antibacterial agents, various additives such as optical brighteners, thermoplastic resins other than essential components, elastomers, fillers, etc. Can be used alone or in combination.

Here, as the thermoplastic resin other than the essential components, for example, ethylene / vinyl acetate copolymer, ethylene / acrylic acid ester copolymer, polyphenylene ether, polyamide, polyester, polyoxymethylene, polymethylmethacrylate, Polybutene-1 and the like.

As the optional elastomer,
For example, ethylene / propylene copolymer rubber (EP
M), ethylene / propylene / non-conjugated diene copolymer rubber (EPDM), ethylene / butene copolymer rubber, ethylene / propylene / butene copolymer rubber and other ethylene-based elastomers, styrene / butadiene copolymer rubber,
Examples include styrene-based elastomers such as styrene-isoprene copolymer rubber and polybutadiene. Furthermore, examples of the filler include talc and calcium carbonate.

Next, the amount ratio of the above components (A) to (F) will be described. The styrene-based thermoplastic elastomer constituting the skin layer of the two-color molded automobile interior part that can be used without coating of the present invention is basically the above-mentioned constituent components (essential components).
(A) to (F) are blended, but the blending ratio of each of these components is particularly important.

The blending amount of the above component (A) is such that the component ratio with the above components (B) and (C) is A: B: C = (1-6):
(1-6): (1-6) and A + B + C = 10, preferably A: B: C = (1-5) :( 1-5) :( 1
~ 5) and in the proportion of A + B + C = 10.

When the ratio of the component (A) exceeds the above range, the flow mark property is deteriorated, and when the ratio of the component (A) is less than the above range, the gloss of the molded product increases and it is not suitable as an interior part. If the ratio of the component (B) exceeds the above range, both the flow mark property and the gloss deteriorate, and if the ratio of the component (B) is less than the above range, the molding appearance deteriorates. When the ratio of the component (C) exceeds the above range, the gloss of the molded product increases and it is unsuitable for interior parts. When the ratio of the component (C) is less than the above range, the flow mark property deteriorates.

Further, the total blending amount of these components (A) to (C) is 40 to 80% by weight, preferably 40 to 70% by weight in 100 parts by weight of the total amount of the above components (D). Used in. Therefore, the blending amount of the component (D) is 60 to 60 parts by weight based on 100 parts by weight of the total amount of the components (A) to (C).
It is used in a proportion of 20% by weight, preferably 60 to 30% by weight. If the compounding amount of the component (D) exceeds the above range, the surface of the molded product becomes sticky. Further, if it is less than the above range, the fluidity at the time of molding becomes poor.

The amount of the above component (E) to be blended is 10 to 60 relative to 100 parts by weight of the total of the above components (A) to (D).
Parts by weight, preferably 15 to 58 parts by weight. If the blending amount of the component (E) exceeds the above range, the molded product is inferior in softness, and if it is less than the above range, the heat resistance deteriorates.

The blending amount of the above component (F) is 1 to 40 parts by weight, preferably 5 to 30 parts by weight, based on 100 parts by weight of the above components (A) to (D). When the compounding amount of the component (F) exceeds the above range, the molded product is inferior in softness, and when it is less than the above range, the surface of the molded product becomes sticky.

Next, the production of the automobile interior parts of the present invention will be described. The automobile interior part of the present invention is a laminated molded body produced by injection-molding a skin material on an injection-molded base material (core material).

As the olefin resin material which can be used as the base material, propylene homopolymer, propylene / ethylene random copolymer, or propylene.
Mention may be made of ethylene block copolymers. These may be used alone or as a mixture of two or more kinds.
Further, in order to impart rigidity and heat resistance to these propylene polymers, an inorganic filler such as glass fiber, talc, calcium carbonate, and whiskers is blended with other auxiliary materials such as various additives including antioxidants. You may use it.

As the olefin resin, JIS K
Flexural modulus according to 7203 is 10,000 kg / cm ²
The above can be used. Flexural modulus is 10,
If it is less than 000 kg / cm ² , mechanical properties such as rigidity and strength, heat resistance and durability required for interior parts for automobiles cannot be satisfied.

The skin material is a styrene thermoplastic elastomer having a JIS-A hardness of 50 to 95, preferably 60 to 93 according to JIS K 6301, which is composed of the above-mentioned components (A) to (F). If the -A hardness exceeds the above range, the soft feel is inferior, and if it is less than the above range, the surface becomes sticky, which is not preferable in terms of dust adhesion. It is important that the average thickness of the epidermis is 1.5 to 3 mm, and those exceeding the above range have poor soft feeling,
If it is less than the above range, the adhesion between the base material and the skin becomes poor.

As a molding method used for manufacturing the interior parts for automobiles of the present invention, a base material (core material) is previously injection-molded,
After inserting the shaped molded product into the mold, an insert molding method in which a skin material is injection-molded in the gap between the molded product and the mold, or using two or more injection molding machines,
After injection molding of the base material, the mold cavity is exchanged by rotating or moving the mold, and a void is created between the molding base material and the mold, and the two-color molding in which the skin material is injection molded. Or a sandwich molding method in which a laminar flow state of molten resin is utilized to form a molded product having a skin and a core.

[0043]

In the present invention, the skin material obtained by blending the styrene-based thermoplastic elastomer component having a specific weight average molecular weight and the specific resin component in a specific ratio as described above forms a skin for a finished automobile interior part. , Low gloss, soft feeling, no stickiness on the surface, excellent in injection molding appearance, resulting in no need to coat the surface.

[0044]

EXAMPLES The present invention will be described in detail below by showing examples of the present invention together with comparative examples. The raw materials, the molding apparatus and the molding method, the method for measuring the physical properties of the skin material, and the method for evaluating the molded product used here are as follows.

1. Raw materials 1) Skin (surface layer) material-Component (A) A-1: SEBS (weight average molecular weight 246,000,
Styrene content 33%, hydrogenation rate ≧ 98% A-2: SEPS (weight average molecular weight 23,800, styrene content 35%, hydrogenation rate ≧ 98%) Component (B) B-1: SEBS (weight average) Molecular weight 110,000,
Styrene content 28%, hydrogenation rate ≧ 98%) B-2: SEPS (weight average molecular weight 105,000,
Styrene content 30%, hydrogenation rate ≧ 98%) Component (C) C-1: SEBS (weight average molecular weight 85,700, styrene content 29%, hydrogenation rate ≧ 98%) C-2: SEPS (weight average). Molecular weight 73,300, styrene content 30%, hydrogenation rate ≧ 98%) Component (D) D-1: Paraffin oil (average molecular weight 746, ring analysis 0%, kinematic viscosity (40 ° C.) 381.6 cSt, flow Point-15.0 ° C, flash point 300 ° C) -Component (E) E-1: Flexural modulus according to JIS K7203 is 1
20,000 kg / cm ² , MFR (230 ° C, 2.16
ethylene / propylene block copolymer having an ethylene content of 8.0% by weight. Component (F) F-1: Density 0.918 g / cm ³ , and MFR (1
90 ° C., 2.16 kg) 4 g / 10 min low density polyethylene F-2: density 0.958 g / cm ³ , and MFR (1
90 ° C, 2.16kg) 20g / 10min high density polyethylene

2) Substrate S-1: Flexural modulus of 1 according to JIS K 7203
5,000 kg / cm², And MFR (230 ° C., 2.
16 kg) is 30 g / 10 min ethylene propylene
Lock copolymer S-2: Flexural modulus according to JIS K 7203
8,500 kg / cm ², And MFR (230 ° C., 2.
16 kg) is 4 g / 10 min ethylene propylene bro
Block copolymer

2. Molding apparatus and molding method The molding apparatus and molding method used are summarized in Table 1 below.

[0048]

[Table 1]

3. Method for measuring physical properties of skin material 1) JIS-A hardness Using three injection-molded sheets having a thickness of 12 mm prepared under the molding conditions shown in Table 1 and having a thickness of 12 mm, JIS K 6301 is used. Measured. 2) Melt flow rate (MFR) According to JIS K 7210. 230 ° C and 190 ° C,
2.16 kg load. 3) Flexural Modulus Using an injection-molded sheet having a thickness of 4 mm prepared under the molding conditions shown in Table 1, it was measured according to JIS K7203.

4. Evaluation Method of Molded Products 1) Injection Moldability (Releasability) In the injection molding under the molding conditions shown in Table 1, those having good mold releasability and no problem were marked with “◯” as shown in Table 2 below. When the molded product was taken to the cavity side when the mold was opened or released, or the molded product could not be taken out smoothly from the core side, it was evaluated as x. 2) Appearance of injection molded product (flow mark) Using a pillar-shaped injection molded product prepared under the molding conditions shown in Table 1, the presence or absence of flow marks was visually evaluated, and as a result, those with almost no flow marks were evaluated as ○. And those with flow marks and the like were marked with x. 3) Appearance of injection-molded product (smoothness) Using a pillar-shaped injection-molded product prepared under the molding conditions shown in Table 1, the smoothness was visually evaluated, and as a result, almost smooth products were evaluated as ◯, surface roughness, etc. Some were marked as x. 4) Appearance of injection-molded article (stickiness) Using a pillar-shaped injection-molded article prepared under the molding conditions shown in Table 1, sensory evaluation was conducted by 10 panelists. And 5) Injection-molded product appearance (gloss) Using a 4 mm-thick injection-molded sheet prepared under the molding conditions shown in Table 1, the gloss value was measured with a gloss meter (gloss 60 °) (manufactured by Suga Test Instruments). , 1.6 or less is ○, 1.6
Those that exceeded were marked with x. 6) Thermal Deformability An injection-molded article similar to that used in the evaluation of the appearance (flow mark) of the above-mentioned injection-molded article was tested at −30 ° C. (8 hours) at 80 ° C.
After 3 cycles of treatment (° C. (8 hours)), the deformation of the molded product was visually evaluated. When deformation was observed, x was given, and when there was almost no deformation, o was given. 7) Soft feeling Using a pillar-shaped injection-molded article prepared under the molding conditions shown in Table 1, sensory evaluation was conducted by 10 panelists, and those having a soft feeling were evaluated as ◯, and those having no soft feeling were evaluated as x.

Examples 1 to 9 The components (A) to (F) were blended in a Henschel mixer according to the formulations shown in Tables 2 and 3, and then 4
Pellets were obtained by melt-kneading at 200 ° C. with a twin-screw extruder having a diameter of 5 mm. The pellets were injection-molded according to the molding conditions and conditions shown in Table 1 to prepare a 120 × 120 × 4 mm molded sheet and a sample for evaluation of the pillar garnish molded body 1 shown in FIG. For each sample,
The measurement and evaluation were performed by the above-mentioned physical property measuring method and evaluation method. The obtained results are shown in Tables 2 and 3.

Comparative Examples 1 to 12 The components (A) to (F) were blended in a Henschel mixer according to the formulations shown in Tables 4 to 6, and then evaluation samples were prepared in the same manner as in the above Examples. The physical properties were measured and the molded product was evaluated. The results are shown in Tables 4-6.

[0053]

[Table 2]

[0054]

[Table 3]

[0055]

[Table 4]

[0056]

[Table 5]

[0057]

[Table 6]

As is apparent from these, in the evaluation of the samples of the examples according to the present invention, good results were obtained in all of the injection moldability, the appearance of the injection molded products, and the heat deformability, whereas the results of the comparative examples were good. In the sample, defects were observed in any of the injection moldability, the appearance of the injection molded product, the heat deformability, and the soft feeling.

Example 10 According to the formulation shown in Table 3, blended by a Henschel mixer, and then melt-kneaded at 200 ° C. by a twin-screw extruder having a diameter of 45 mm to obtain pellets. Using this pellet, Table 1
The pillar garnish molded article injection-molded according to the molding conditions of 1. was evaluated as an automobile interior product under the following conditions.

[0060] Evaluation absence of items conditions standards heat resistance 80 ° C. × 20h deformation (hereinafter ± 0.5%) humidity resistance 50 ° C., the absence of 95 RH% × 20h deformation (hereinafter ± 0.5%) aging resistance 80 ° C. × 400 h No cracks, cracks or discoloration Moisture aging 50 ℃, 95RH% × 400 h No cracks, cracks or discoloration

The results show that all the pillar garnish moldings have no abnormality in all the items, and the deformation amounts in the evaluation of heat resistance and moisture resistance are 0.35 m each.
m, 0.45 mm, and no remarkable deformation was observed.

As described above, since the molded product according to the present invention satisfies the performance as the interior parts for automobiles, in addition to the pillar garnish, the same automobile parts such as an instrument panel, an instrument panel lower, and an airbag. Cover, door grab, console box, door trim, shift knob, assist grip, seat adjuster, remote control switch, sun visor, rearview mirror cover, room mirror cover, cup holder, coin box, register, ashtray upper, door frame garnish, column cover, armrest. It can be applied to all automobile interior parts that can be molded by injection molding (injection molding, sandwich molding, gas injection, two-color molding, two-layer molding), such as inner panels and louver garnishes. .

As an example, FIG. 2 shows an example in which the molded product of the present invention is applied to a remote control switch. The remote control switch 10 shown in this figure is composed of a base material 11, an outer skin 12, and a push switch 13, and is operated by pressing the outer skin. Such a remote control switch is used, for example, as a switch for opening and closing a garage by remote control from the inside of a car (garage opener) or as a remote control switch for car audio, and it is housed in a case as a whole. It is something.

In the automobile interior part of the present invention, the base material can be made of a material other than the olefin resin. When a material other than an olefin-based material is used, that is, when welding of the base material and the skin material cannot be expected, in order to fix the skin to the base material, for example, as illustrated in FIG. It is possible to form a through hole 25 in the base material 21 and allow a part of the material forming the skin 22 to wrap around the back side of the base material 21 through the through hole. Also,
As another example, as shown in FIG. 4, the outer skin may be fixed by wrapping the tip of the outer skin 32 around the back side of the base material at the end portion of the base material 31. Further, even when the adhesion between the base material and the epidermis is poor because the epidermis is less than 1.5 mm, the epidermis is fixed by wrapping the tip of the epidermis around the back side of the base material at the through hole or the end portion in the same manner. be able to.

[0065]

As is apparent from the above description, according to the present invention, since it is possible to prevent the stickiness of the skin of an automobile interior part having an elastomer skin, surface parts such as painting are unnecessary. It becomes possible to provide. The interior parts for automobiles provided with the elastomer skin of the present invention are excellent in the appearance of injection molded articles other than stickiness, and also have good heat resistance, moisture resistance, heat aging, and moisture aging resistance. Since it has excellent properties, it can be very conveniently used as various interior parts as described above.

[Brief description of drawings]

FIG. 1 is a perspective view showing a pillar garnish produced in Examples and Comparative Examples of the present invention.

FIG. 2 is a diagram illustrating a remote control switch that is an example of an interior component according to the present invention.

FIG. 3 is a diagram illustrating an example of a method of fixing a base material and a skin when the base material is made of a material other than an olefin resin.

FIG. 4 is a diagram illustrating another example of a method of fixing the base material and the skin when the base material is made of a material other than the olefin resin.

[Explanation of symbols]

 1 ... Pillar garnish 10 ... Remote control switch 11 ... Base material 12 ... Skin 13 ... Push switch 21 ... Base material 22 ... Skin 25 ... Through hole 31 ... Base material 32 ... Skin

[Procedure amendment]

[Submission date] October 28, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0045

[Correction method] Change

[Correction content]

1. Raw materials 1) Skin (surface layer) material-Component (A) A-1: SEBS (weight average molecular weight 246,000,
Styrene content 33%, hydrogenation rate ≧ 98% A-2: SEPS (weight average molecular weight 238,000 ,
Styrene content 35%, hydrogenation rate ≧ 98%) Component (B) B-1: SEBS (weight average molecular weight 110,000,
Styrene content 28%, hydrogenation rate ≧ 98%) B-2: SEPS (weight average molecular weight 105,000,
Styrene content 30%, hydrogenation rate ≧ 98%) Component (C) C-1: SEBS (weight average molecular weight 85,700, styrene content 29%, hydrogenation rate ≧ 98%) C-2: SEPS (weight average). Molecular weight 73,300, styrene content 30%, hydrogenation rate ≧ 98%) Component (D) D-1: Paraffin oil (average molecular weight 746, ring analysis 0%, kinematic viscosity (40 ° C.) 381.6 cSt, flow Point-15.0 ° C, flash point 300 ° C) -Component (E) E-1: Flexural modulus according to JIS K7203 is 1
20,000 kg / cm ² , MFR (230 ° C, 2.16
ethylene / propylene block copolymer having an ethylene content of 8.0% by weight. Component (F) F-1: Density 0.918 g / cm ³ , and MFR (1
90 ° C., 2.16 kg) 4 g / 10 min low density polyethylene F-2: density 0.958 g / cm ³ , and MFR (1
90 ° C, 2.16kg) 20g / 10min high density polyethylene

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0060

[Correction method] Change

[Correction content]

[0060] absence of endpoint conditions standards heat resistance 80 ° C. × 20h deformation (± 0.5 mm or less) Moisture resistance 50 ° C., the absence of 95 RH% × 20h deformation (± 0.5 mm or less) aging resistance 80 ° C. × 400 h No cracks, cracks or discoloration Moisture aging 50 ℃, 95RH% × 400 h No cracks, cracks or discoloration

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takaryu Suzuki 3-30 Shimomarket-cho, Toyota-shi, Aichi Kojima Press Kogyo Co., Ltd. (72) Inventor Kazunori Aotsuka 1-cho, Toyota-shi, Aichi Toyota Motor Vehicle Incorporated (72) Inventor Kazuo Ito 1 Toyota-cho, Toyota-shi, Aichi Toyota Automobile Co., Ltd. (72) Inventor Hideki Takahashi 1 Toho-cho, Yokkaichi-shi, Mie Mitsubishi Petrochemical Company Yokkaichi Research Institute ( 72) Inventor Yoshinori Nishitani No. 1, Toho-cho, Yokkaichi-shi, Mie Mitsubishi Petrochemical Company Yokkaichi Research Institute

Claims (4)

[Claims] 1. A flexural modulus of 10,000 kg / cm ^2.
The above olefin resin base material and the following respective components (A)
The components (A) to (C) of (F) are A: B: C = (1 to
6): (1-6): (1-6) and A + B + C = 1
It is blended at a component ratio of 0, and these components (A) to
The mixing ratio of the component (D) to the total of 40 to 80% by weight of (C) is 60 to 20% by weight, and the component (E) is added to 100 parts by weight of the total of these components (A) to (D). 10 to 60 parts by weight of the component (F) and 1 to 40 parts by weight of the component (F), and a JIS-A hardness of 50 to 95 and an average wall thickness of 1.5 to 3 mm. An interior part for an automobile, which is characterized in that (A) Weight average molecular weight 150,000 to 300,000
Hydrogenated product of styrene / conjugated diene block copolymer (B) Weight average molecular weight 100,000 to 150,000
Hydrogenated product of styrene / conjugated diene block copolymer (C) Hydrogenated product of styrene / conjugated diene block copolymer (C) Weight average molecular weight less than 50,000-100,000 (D) Paraffin oil (E) Polypropylene resin (F) Polyethylene resin with a density of 0.940 g / cm ³ or less 2. The automobile interior component according to claim 1, wherein the styrene content of the components (A) to (C) is 5 to 50% by weight, and the hydrogenation rate is 95% or more. 3. The kinematic viscosity of the component (D) at 40 ° C. is 2
0-800 cSt, pour point 0--40 ° C, flash point 2
The automobile interior part according to claim 1 or 2, which has a temperature of 00 to 400 ° C. 4. The automobile interior according to any one of claims 1 to 3, wherein the melt flow rate of the component (E) is 0.01 to 80 g / 10 minutes and the ethylene content is 15% or less. parts.