JP3160569B2 - Slush molded skin and molded body using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a slush-molded skin and a molded article using the same, and more particularly, to a slush having excellent mold release properties and good adhesion between the skin and a foam layer or a core material. The present invention relates to a molded skin and a molded article using the same.

[0002]

2. Description of the Related Art As a powder molding method using a soft powder material, a powder slash molding method using a soft vinyl chloride resin powder is used for an instrument panel, a console box,
Widely used for the skin of car interior parts such as door trim. This is a soft touch, and can be provided with leather grain and stitches, and has good design properties such as a large degree of freedom in design.

[0003] Unlike other molding methods such as injection molding and compression molding, this molding method does not apply a shaping pressure. Therefore, in order to uniformly adhere a powder material to a mold having a complicated shape at the time of molding, powder molding is performed. In some cases, the powder has excellent fluidity, so that the powder attached to the mold melts and flows even under no pressure to form a film. In addition, it was necessary that the skin formed by cooling the mold could be released more easily than the mold.

As one method for improving this, Japanese Patent Application Laid-Open No. Hei 7-82433 discloses that a polypropylene resin and a specific styrene-based thermoplastic elastomer have a weight ratio of 70/3.
It has been proposed to pulverize and use a mixture of 0 to 30/70. Here, the styrene-based thermoplastic elastomer contains styrene having a styrene content of 20% by weight or less.
An ethylene butylene / styrene block copolymer, a styrene / ethylene propylene / styrene block copolymer having a styrene content of not more than 20% by weight, and a styrene content of 20
The composition is selected from hydrogenated styrene-butadiene rubber having a weight percentage of not more than 1, and has a good compatibility with the polypropylene resin and is suitable for powder molding.

[0005]

However, even with this composition, the hydrogenated styrene-butadiene rubber is finely dispersed in the polypropylene resin when the polypropylene resin and the hydrogenated styrene-butadiene rubber are mixed. Are suitable. However, since the hydrogenated styrene-butadiene rubber has poor oil-absorbing ability, the oligomer component in the composition has migrated to the surface and has a disadvantage of having tackiness. For this reason, the thermoplastic elastomer powder pulverized for powder slush molding also has adhesiveness, so that it is easy to block and the powder fluidity is poor. Further, when the outer skin is also released from the mold, the releasability may be deteriorated, and the outer skin after the releasing may be deformed.

[0006] As described above, the skin obtained from the conventional thermoplastic elastomer composition has not been obtained in which both the mold releasability and the adhesiveness are improved, and one of the required items is unsatisfactory. Met. Conventionally, a thermoplastic elastomer composition that satisfies the mold releasability has been improved, and a primer or an adhesive has been applied to the molded skin to increase the adhesiveness. However, many of the skins after the adhesive treatment have adhesiveness on the treated surface, cannot be stacked, and occupy a considerable space when storing the skin.

The present invention has been made to solve the above problems, and has a slush-molded skin which is excellent in mold releasability and has good adhesion between a skin and a foam layer or a core material. The purpose is to provide a molded article.

[0008]

That is, according to the first aspect of the present invention, in a slush-molded skin comprising at least a surface layer and an inner layer obtained by powder slush molding, at least a polypropylene resin as the surface layer and hydrogen Slurry molding powder of a thermoplastic elastomer composition comprising an added styrene-butadiene rubber, a process oil, an elastomer having excellent oil-absorbing ability, and an internal release agent, and further forming at least a polypropylene resin as an inner layer thereof, and hydrogenated styrene-butadiene. The slush-molded skin is obtained by slush-molding a powder containing rubber, process oil, an elastomer having excellent oil-absorbing ability, an adhesion improver, and a thermoplastic polyurethane elastomer. The above-mentioned slush-molded skin is produced by slush molding in which at least two layers consisting of a surface layer and an inner layer are continuously formed, and the surface layer imparts excellent mold release properties, while the inner layer has excellent adhesiveness. .

In a second aspect of the present invention, a thermoplastic elastomer composition containing at least a polypropylene resin, a hydrogenated styrene-butadiene rubber, a process oil, an elastomer having excellent oil absorption, and an adhesion improver as an inner layer. And a thermoplastic polyurethane elastomer powder in a slush-molded skin obtained by slush molding.

In the invention according to claim 3 of the present application, the slush molding in which the mixing weight ratio of the mixed powder of the thermoplastic elastomer composition powder and the thermoplastic polyurethane elastomer powder in the inner layer is 1: 5 to 5: 1. On the epidermis.

According to the invention of claim 4 of the present application, the thermoplastic elastomer composition for powder slush molding in which the weight ratio of the polypropylene resin and the hydrogenated styrene-butadiene rubber is 80/20 to 20/80 in the surface layer and the inner layer. is there.

According to the fifth aspect of the present invention, in the surface layer and the inner layer, the elastomer having excellent oil absorbing ability is used in an amount of 20 to 2 parts by weight per 100 parts by weight of the hydrogenated styrene butadiene rubber.
50 parts by weight of the thermoplastic elastomer composition for powder slush molding to be mixed.

[0013] In the invention according to claim 6 of the present application, the elastomer having excellent oil absorbing ability is made of styrene, ethylene propylene, or styrene.
Styrene block copolymer (SEPS), styrene / ethylene butylene / styrene block copolymer (SEB)
S), a thermoplastic elastomer composition for powder slush molding which is at least one polymer selected from olefin crystal / ethylene butylene / olefin crystal block copolymer, ethylene propylene rubber, and ethylene / octene copolymer (POE). is there.

The invention according to claim 7 of the present application resides in a slush-molded skin in which process oil is mixed in the surface layer and the inner layer in an amount of 5 to 200 parts by weight with respect to 100 parts by weight of an elastomer having excellent oil absorbing ability.

In the invention according to claim 8 of the present application, the internal release agent in the surface layer is selected from acid-modified polypropylene, hydroxyl-containing polypropylene, hydrogenated polypropylene having hydroxyl groups at both ends, and a hydrolyzate of an ethylene / vinyl acetate copolymer. And at least one or more polymers
It is on the lash molded skin containing 20% by weight.

In the invention according to claim 9 of the present application, the adhesion improver in the inner layer is at least one selected from an acid-modified polypropylene, a hydroxyl-containing polypropylene, a hydrogenated polypropylene having hydroxyl groups at both ends, and a hydrolyzate of an ethylene-vinyl acetate copolymer. 2-2 of one or more polymers
It is in the slush molded skin containing 0% by weight.

According to the invention of claim 10 of the present application, a laminate having a foamed layer interposed between a slash-molded skin composed of at least a surface layer and an inner layer obtained by powder slush molding and a core material composed of a synthetic resin is provided. In a molded product having a slush molded skin, the slush molded skin has at least a polypropylene resin as a surface layer, a hydrogenated styrene-butadiene rubber, a process oil, an elastomer having excellent oil absorbing ability, and a thermoplastic resin having an internal mold release agent. Slush molding of the powder of the elastomer composition, further at least a polypropylene resin as an inner layer thereof, hydrogenated styrene butadiene rubber, a process oil, an elastomer having excellent oil absorption, an adhesion improver,
The slush-molded body is a composite skin obtained by slush-molding a powder containing a thermoplastic polyurethane elastomer. The slush-molded skin is slush-molded continuously with at least two layers consisting of a surface layer and an inner layer. The surface layer has excellent mold release properties, and the skin is deformed even when the mold is released from the mold. Less, on the other hand, the inner layer is excellent in adhesiveness and satisfactorily joined to the foam layer and the core material.

According to the present invention, a thermoplastic elastomer composition containing at least a polypropylene resin, a hydrogenated styrene-butadiene rubber, a process oil, an elastomer having excellent oil absorption, and an adhesion improver as an inner layer. And a thermoplastic polyurethane elastomer powder in a slush molded skin.

According to the invention of claim 12 of the present application, there is provided a molded product with a slush molded skin, wherein the foamed layer is a polyurethane foam.

According to the invention of claim 13 of the present application, there is provided a molded product having a slush molded skin whose core material is an olefin resin.

[0021]

FIG. 1 is a perspective view of the entire outer appearance of an instrument panel for a vehicle, which is one of the molded bodies with a skin, FIG. 2 is a sectional view taken along line XX of FIG. 1, and FIG. A
It is a part enlarged view. According to this, the instrument panel 1 is divided into a software section 2 and a hardware section 3,
On the front surface, a slush molded skin 4 composed of a surface layer 4a and an inner layer 4b having a textured pattern is covered, and a core material 5 made of a synthetic resin is located on the back surface. A foam layer 6 such as a polyurethane foam is provided between the members 5. On the other hand, hardware part 3
In this case, the core material 5 is in close contact with the slush-molded skin 4 consisting of the surface layer 4a and the inner layer 4b.

The slush-molded skin 4 is a composite skin composed of a surface layer 4a and an inner layer 4b. The surface layer 4a is composed of at least a polypropylene resin, a hydrogenated styrene-butadiene rubber, a process oil, and an elastomer having excellent oil absorption. Then, the powder of the thermoplastic elastomer composition comprising the internal release agent is subjected to slush molding. On the other hand, the inner layer 4b is formed by slush molding a powder containing at least a polypropylene resin, a hydrogenated styrene-butadiene rubber, a process oil, an elastomer having excellent oil absorption, an adhesion improver, and a thermoplastic polyurethane elastomer. Since the surface layer 4a contains an internal mold release agent, the releasability from the mold is also improved, and the inner layer 4b contains an adhesion improver and a thermoplastic polyurethane elastomer. The adhesive strength is improved.

Surface layer 4 of slush molded skin 4 of the present invention
a and the polypropylene resin used for the inner layer 4b may be any of a polypropylene homopolymer, a block copolymer with an α-olefin, or a random copolymer.
A block or random copolymer using ethylene as the olefin is preferred from the viewpoint of the flexibility of the molded article. In addition, in order to use the powder slush molding without applying pressure, it is necessary to determine the melt fluidity index of the polypropylene resin according to JIS K7210 at 230 ° C. and a load of 2.1.
MFR (melt flow rate) measured at 6 kgf is 2
It is necessary to be 0 g / 10 minutes or more. The polypropylene resin is a polymer whose main chain is cut by heat or oxidation, and has a property different from that of polyethylene or the like which crosslinks and hardens. The main chain is cut by an organic peroxide, and the molecular weight is reduced.

The hydrogenated styrene-butadiene rubber (H-SBR) used for the surface layer 4a and the inner layer 4b of the slush-molded skin 4 of the present invention has excellent compatibility with a polypropylene resin. A thermoplastic elastomer composition which is flexible and hard to bend or whiten is obtained. The styrene content of the hydrogenated styrene-butadiene rubber is preferably 30% by weight or less, and 5 to 15% by weight is appropriate for obtaining a flexible skin.

H-SBR differs from SEBS which is a block copolymer in that styrene-butadiene rubber in which styrene and butadiene are randomly copolymerized is hydrogenated. A typical example is the Dynalon series, a product made by Nippon Synthetic Rubber Co., Ltd.

The mixing amount of the polypropylene resin and H-SBR is 80/20 to 20/80 by weight.
When the amount of the polypropylene resin increases, the formed skin becomes hard, while when the amount decreases, the tensile strength decreases.

The process oil used for the surface layer 4a and the inner layer 4b of the slush molded skin 4 of the present invention is absorbed by the elastomer component in the composition to lower the melt viscosity and lower the hardness of the skin. It has the effect of giving flexibility. The above process oils are used for rubber and are classified into paraffinic, naphthenic, and aroma-based oils. Paraffin-based oils are preferred because of their compatibility with elastomer components. The addition amount is preferably 5 to 200 parts by weight based on 100 parts by weight of the elastomer having excellent oil absorbing ability. If it exceeds 200 parts by weight, the tensile properties are reduced, and if it is less than 5 parts by weight, the melt viscosity does not decrease and the skin becomes hard.

Surface layer 4 of slush molded skin 4 of the present invention
The elastomer having excellent oil-absorbing ability used for a and the inner layer 4b is compatible with the polypropylene resin and has a property of absorbing the process oil and the oligomer component in the composition. Block copolymer (SEBS) and styrene / ethylene propylene / styrene block copolymer (SEPS)
Styrenic block copolymer thermoplastic elastomer such as
Olefin crystal / ethylene butylene / olefin crystal block copolymer (CEBC), ethylene propylene rubber (EPR), and ethylene / octene copolymer (P
OE).

The above SEBS is obtained by hydrogenating a styrene / butadiene / styrene block copolymer (SBS), and includes Clayton G series, a product of Ciel Chemical Co., Ltd., and Tuftec H series, a product of Asahi Kasei Corporation. No. In this SEBS, the strength increases as the styrene content increases, but the flexibility decreases. Also,
In the case of the SEBS, the styrene hard segments may be aggregated due to melting at the time of slush molding, and it may be difficult to obtain a smooth sheet-like molded body. Therefore, the styrene content is preferably 40% by weight or less.

SEPS is obtained by hydrogenating styrene / isoprene / styrene block copolymer (SIS).
Septon, a product made by Kuraray Co., is representative. SE
As in the case of BS, the styrene content is preferably 40% by weight or less because the flexibility decreases as the styrene content increases.

The above-mentioned elastomer having excellent oil-absorbing ability is:
Compared with H-SBR, the compatibility with the polypropylene resin is inferior, and when kneaded and added to the polypropylene resin, it is dispersed in a size of μm unit, so that the tensile properties tend to decrease. However, the HS
When BR and process oil are added, H-SBR
Is poor in oil-absorbing ability, so that the oligomer component in the composition migrates (bleeds) to the surface and has tackiness, and the elastomer powder crushed for powder slush molding using this also has tackiness, so it is easy to block. Powder flow,
In addition, the skin also lacks releasability from the mold. When an elastomer having an excellent oil-absorbing ability is added thereto, the bleed can be prevented by absorbing the oligomer component and the oil in the composition.

The amount of the elastomer having excellent oil absorbing ability is 20 to 250 parts by weight based on 100 parts by weight of H-SBR. If the amount is less than 20 parts by weight, the oligomer component and oil in the composition cannot be sufficiently absorbed, and
If the amount exceeds 0 parts by weight, the dispersion with the polypropylene resin becomes poor, and the tensile properties tend to decrease.

Surface layer 4 of slush molded skin 4 of the present invention
Examples of the internal release agent used for a include dimethylsiloxane, methylhydroxypolysiloxane, and methylphenylpolysiloxane. The amount of addition is 0.1 ~
When the content is less than 0.1% by weight, a sufficient releasing effect cannot be obtained. On the other hand, when the content is more than 5.0% by weight, the adhesion to the inner layer is inhibited.

On the other hand, the adhesion improver used in the inner layer 4b of the slush molded skin 4 of the present invention is a low molecular weight polymer having a carboxyl group or a hydroxyl group which reacts with isocyanate, or an acid-modified polyolefin. Modified polypropylene, hydroxyl-containing polypropylene, polypropylene having both ends hydroxyl-hydrogenated, and a hydrolyzate of an ethylene-vinyl acetate copolymer can be given. The addition amount is preferably 2 to 20% by weight,
If the amount is less than 20% by weight, the effect of improving the adhesion is small, while if it exceeds 20% by weight, the tensile strength is greatly reduced.

The inner layer 4b of the slush molded skin 4 of the present invention
Is 50 to 90% by weight in the powder composition of the inner layer 4b. Specifically, the weight of the thermoplastic elastomer composition powder containing the polypropylene resin, the hydrogenated styrene-butadiene rubber, the process oil, the elastomer having excellent oil absorbing ability, and the adhesion improver is 0.1 wt. It is added 2 to 5 times. When the ratio is less than 0.2 times, the adhesion to the surface layer 4a is insufficient, and delamination is likely to occur. On the other hand, when the ratio exceeds 5 times, the adhesion to the foam layer 6 is insufficient. The average particle size of the thermoplastic polyurethane elastomer powder is 100 to 5
It is 00 μm, and preferably 150 to 200 μm. Incidentally, the amount of the thermoplastic polyurethane elastomer powder to be added can be adjusted by the particle diameter.

Surface layer 4 of slush molded skin 4 of the present invention
As the heat stabilizer that can be used for a and the inner layer 4b, those used for ordinary polyolefins can be used. Generally, phenol and a phosphorus-based antioxidant are used in combination, but are not particularly limited. As the light stabilizer, a hindered amine or benzotriazole type radical scavenger may be used. Organic and inorganic pigments suitable for ordinary olefins are used. Further, a lubricant such as a fatty acid metal salt and a filler such as calcium carbonate and talc are added as required.

The mixture of these compounds used for the surface layer of the slush-molded skin is polypropylene resin, H-SB
R, process oil, elastomer with excellent oil absorption, pigment, stabilizer, and lubricant are dry-blended using a V-type blender, tumbler, Henschel mixer, etc., and supplied from a raw material supply hopper, and process oil is injected from a vent port. Then, the mixture is melt-kneaded with a twin-screw extruder and pelletized.

Further, in the present invention, an organic peroxide is added to the same composition comprising the above-mentioned polypropylene resin, H-SBR, process oil, elastomer having excellent oil-absorbing ability, and an internal mold release agent. Kneading under heating, the organic peroxide cuts the main chain of the polypropylene resin, lowering the molecular weight of the polypropylene resin and increasing the melt fluidity, resulting in a high melting point in the obtained thermoplastic elastomer composition. It has the effect of giving liquidity. Here, the organic peroxide is not used as a crosslinking agent. Further, in the thermoplastic elastomer composition obtained by kneading under heating, the organic peroxide is thermally decomposed and substantially not contained.

As the above-mentioned organic peroxide, usually, rubber,
Diacyl peroxide used for crosslinking of resin,
Peroxyester, diallyl peroxide, di-t
-Butyl peroxide, t-butylcumyl peroxide, dicumyl peroxide, 2.5-dimethyl-2
.5-di (t-butylperoxy) -hexane-3,1
• 3-bis (t-butylperoxy-isopropyl) benzene, 1,1-di-butylperoxy-3,3,5-
Trimethylcyclohexane and the like, and those having a one-minute half-life by thermal decomposition of 150 to 250 ° C. are preferable.

In the process of kneading under heating at 120 to 250 ° C., the organic peroxide cuts the main chain of the polypropylene resin to reduce the molecular weight, and gives the thermoplastic elastomer composition high melt fluidity. The amount of the organic peroxide to be added is 0.02 to 5.0% by weight in the thermoplastic elastomer composition. When the amount is less than 0.02% by weight, the decomposition ability to cut the main chain of the polypropylene resin is small, High melt fluidity cannot be imparted to the thermoplastic elastomer composition. On the other hand, if the content exceeds 5.0% by weight, the decomposition becomes excessive and the mechanical properties such as the tensile strength of the powder molded product are reduced.

The mixture of these compounds is obtained by mixing a polypropylene resin, H-SBR, an elastomer having excellent oil absorbing ability, an internal release agent, an organic peroxide, a pigment, a stabilizer, a lubricant and a filler with V.
Dry blended using a type blender, tumbler, Henschel mixer, etc., is supplied from a raw material supply hopper, and process oil is injected from a vent port,
The mixture is melt-kneaded and pelletized by a twin-screw extruder whose temperature is controlled in the range of 250 ° C.

[0042] The elastomer component H- is mixed with a kneader, a Banbury mixer or the like, which is an internal mixer.
Process oil is added to the SBR and the elastomer having excellent oil absorbing ability, kneaded, and pelletized. Then, the pellet and the polypropylene resin are mixed with an organic peroxide and other compounding agents, and the temperature is in a range of 120 to 250 ° C. The mixture can be melt-kneaded with a single-screw or twin-screw extruder whose temperature has been adjusted to form pellets.

The melt flow rate (MFR), which is the melt viscosity of the obtained pellets, is 2 according to JIS K7210.
It is preferably at least 5 g / 10 min at 50 ° C. and a load of 0.325 kgf. If it is less than this, the melt fluidity of the composition tends to be low, and pinholes tend to occur in the skin.

Pellets obtained from a blend mainly comprising a polypropylene resin, H-SBR, process oil, an oil-absorbing elastomer, and an internal mold release agent, or obtained by adding an organic peroxide thereto. The pellets are finely pulverized using an impact type fine pulverizer such as a turbo mill, a pin mill, a hammer mill, or the like. At this time, it is usually frozen and pulverized using liquid nitrogen. Further, depending on the composition, the molten resin can be powderized by spraying or cooling with a spray or disk atomizer. The crushed material has a particle size of at least 1,000 μm by sieving or the like.
, And those having an average particle size of 100 to 800 µm are collected, and an organic or inorganic powdery improver is added thereto, mixed and used for powder slush molding.

Mixing of these compounds used for the inner layer 4b of the slush molded skin 4 includes at least a polypropylene resin, a hydrogenated styrene-butadiene rubber, a process oil, an elastomer having excellent oil absorbing ability, an adhesion improver, And it is a powder obtained by mixing a thermoplastic polyurethane elastomer, and specifically contains at least a polypropylene resin, a hydrogenated styrene-butadiene rubber, a process oil, an elastomer excellent in oil absorbing ability, and an adhesion improver It is a mixed powder of a thermoplastic elastomer composition powder and a thermoplastic polyurethane elastomer powder, and the pulverization of the thermoplastic elastomer composition is as described above, and the mixing weight ratio of these mixed powders is also
The powder of the thermoplastic polyurethane elastomer is 0.2 to 5 with respect to the powder 1 of the thermoplastic elastomer composition.

Next, slush molding is performed using the powder of the elastomer composition. In this molding, the surface layer 4a
This is dropped mainly by gravity into a mold heated to the melting point of the composition to be used or more, and after a certain time, the mold is inverted and excess composition is collected in a collection box. The composition adheres as a layer to the mold surface, and melts over time to form a surface layer having a thickness of 0.3 to 1.0 mm. Subsequently, the composition to be used for the inner layer 4b is dropped onto the surface layer and charged, and after a certain period of time, the mold is inverted, and the excess composition is collected in a collection box. The layer adhering to the surface layer 4a melts with the passage of time to form an inner layer having a thickness of 0.1 to 0.5 mm. Then, the mold is cooled and the slash-molded skin 4
This is repeatedly performed.

As a method of heating the mold, a method of circulating the oil or putting it into a hot blast stove is generally used. Oil circulation is easy to adjust the mold temperature by pipe arrangement, but is heated only from the mold surface. On the other hand, when a hot blast stove is used, heating can be performed from both sides of the mold surface and the back surface of the molded product. It is necessary to consider the prescription and conditions so as not to cause oxidative deterioration.

The hot air method is effective when performing powder slush molding in multiple layers (2 or 3). That is, the first powder to be the outermost layer is slush-molded in a heated mold,
The powder is deposited a second time in a semi-molten state and, if necessary, slushed a third time, then heat melted. In this case, if the heating is performed only from the mold surface side, the heat transfer is insufficient, so that a hot blast stove method capable of heating from the back surface of the molded product is often used.

The slush molded skin 4 obtained by the above powder slush molding is mounted on one mold so that the surface layer 4a contacts the mold surface. A core material 5 made of a synthetic resin such as polypropylene, ABS, or polystyrene is placed in the other mold, and a foaming solution such as polyurethane is cast between these to form a foamed layer 6 to form a slush adult skin. To form a molded body.

[0050]

Next, the present invention will be described in more detail with reference to specific examples. Examples 1 and 2 and Comparative Example 1 Raw materials for a twin-screw extruder (PCM45, manufactured by Ikegai Iron & Steel Co., Ltd.) obtained by dry blending the materials shown in Table 1 (mixing for the surface layer and the inner layer) with a tumbler excluding the process oil. It is supplied from the supply hopper, and while the process oil is injected from the vent port, the cylinder temperature is 210 ° C and the screw rotation speed is 3.
The mixture was kneaded and extruded at 00 rpm to form pellets. Then, pellets immersed in liquid nitrogen were put into a Turbomill T250-4J (manufactured by Turbo Kogyo Co., Ltd.) and pulverized to collect only a 1,000 μm sieve.

Next, slush molding was performed using the powder for the surface layer. As a method of slush molding, for example, 150 mm × 150 mm × 3 m
m is heated in an oven to 250 ° C., and about 800 g of the above powder is placed on the plate for about 10 seconds to adhere the powder. Heating was performed for 60 seconds in a controlled oven to form a surface layer having a thickness of 0.6 mm. Subsequently, about 800 on this surface layer
g of the inner layer powder was placed for about 10 seconds to form a 0.2 mm layer. Thereafter, the mixture was melted again in an oven adjusted to 300 ° C. for about 60 seconds, then taken out of the oven and cooled with water, and the skin having a thickness of about 0.8 mm was removed.

The quality of the difficulty in removing the epidermis was judged by feeling. ○ is good and × is bad. In the evaluation of the adhesion, 340 × 2 having a dent of 300 × 200 × 8 mm
Using an iron plate of 00 × 12 mm as a mold, after heating in an oven at 40 ° C., place a skin on the bottom of the hollow, inject about 100 g of a pre-mixed semi-rigid urethane foam raw material liquid, immediately seal with an aluminum plate, and seal at 40 ° C. The resultant was heated in an oven C for 4 minutes to obtain a skin and a urethane foam laminate. This is width 2
The sample was cut into 5 mm and 150 mm in length to obtain a sample for evaluation. The 180 ° peel strength and peel state between the skin and the urethane foam layer were evaluated at a tensile speed of 200 mm / sec. When the peel strength exceeds 5 N / 25 mm, ◎, 1
で は in the range of ５5 N / 25 mm, and × in the case of less than 1 N / 25 mm. In the peeling state, the case of cohesive failure of the entire urethane foam was evaluated as ○, the case of partial cohesive failure was evaluated as Δ, and the case of entire surface interface fracture was evaluated as ×. These results are also shown in Table 1.

[0053]

[Table 1]

As a result, in the examples, it is found that the releasability of the skin from the mold is good, and the peel strength between the inner layer of the skin and the urethane foam is high.

[0055]

As described above, according to the first to ninth aspects of the present invention, at least a polypropylene resin, a hydrogenated styrene-butadiene rubber, a process oil, and an elastomer having excellent oil-absorbing ability are used as the surface layer of the slush molded skin. And slush-molding a thermoplastic elastomer composition powder comprising an internal mold release agent, and further bonding at least a polypropylene resin, a hydrogenated styrene-butadiene rubber, a process oil, and an elastomer having excellent oil absorbing ability as an inner layer thereof. In the slush-molded skin obtained by slush-molding a powder containing a thermoplastic polyurethane elastomer with an improver, at least two layers consisting of a surface layer and an inner layer are continuously slush-molded, and the surface layer has excellent mold release properties. While the inner layer is excellent in adhesiveness.

In the invention according to claims 10 to 13 of the present application, the slush-molded skin has at least a polypropylene resin, a hydrogenated styrene-butadiene rubber, a process oil, an elastomer having excellent oil absorbing ability as a surface layer, and Slush molding of a thermoplastic elastomer composition powder comprising a release agent, at least a polypropylene resin as an inner layer thereof, hydrogenated styrene butadiene rubber, a process oil, an elastomer having excellent oil absorption, an adhesion improver, And in the molded body with slush molded skin, which is a composite skin obtained by slush molding a powder containing a thermoplastic polyurethane elastomer, the surface layer of the slush molded skin has characteristics excellent in mold release properties of the mold, Even if the mold is removed from the mold, there is little deformation of the skin, while the inner layer Excellent adhesion, good bonded with the foam layer and the core material.

[Brief description of the drawings]

FIG. 1 is an overall external perspective view of an automotive instrument panel according to the present invention.

FIG. 2 is a sectional view taken along line XX of FIG.

FIG. 3 is an enlarged view of a portion A in FIG. 2;

[Description of sign]

 DESCRIPTION OF SYMBOLS 1 Instrument panel 2 Soft part 3 Hard part 4 Slash molded skin 4a Surface layer 4b Inner layer 5 Core material 6 Foam layer

Continuation of the front page (51) Int.Cl. ⁷ Identification symbol FIB29L 9:00 31:58 (56) References JP-A-10-30036 (JP, A) JP-A 10-231392 (JP, A) JP-A-7-173366 (JP, A) JP-A-7-137202 (JP, A) JP-A-6-329954 (JP, A) JP-A-5-208467 (JP, A) JP-A-2-269138 (JP JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B32B 1/00-35/00 B29C 41/18 B29C 43/00-43/58 B29C 45/00-45/84

Claims (13)

(57) [Claims] 1. A slush-molded skin comprising at least a surface layer and an inner layer obtained by powder slush molding, wherein the surface layer has at least a polypropylene resin, a hydrogenated styrene-butadiene rubber, a process oil, and an elastomer having excellent oil-absorbing ability. And slush-molding a thermoplastic elastomer composition powder comprising an internal mold release agent, and further bonding at least a polypropylene resin, a hydrogenated styrene-butadiene rubber, a process oil, and an elastomer having excellent oil absorbing ability as an inner layer thereof. A slush molded skin obtained by slush molding a powder containing an improving agent and a thermoplastic polyurethane elastomer. 2. A powder of a thermoplastic elastomer composition containing at least a polypropylene resin as an inner layer, a hydrogenated styrene-butadiene rubber, a process oil, an elastomer having excellent oil absorption ability, and an adhesion improver, and a thermoplastic polyurethane elastomer. The slush-molded skin according to claim 1, wherein the mixed powder with the powder is slush-molded. 3. The slush according to claim 1, wherein the mixing weight ratio of the mixed powder of the thermoplastic elastomer composition powder and the thermoplastic polyurethane elastomer powder in the inner layer is 1: 5 to 5: 1. Molded skin. 4. In the surface layer and the inner layer, the polypropylene resin and the hydrogenated styrene-butadiene rubber have a weight ratio of 80.
The slush-molded skin according to claim 1 or 2, wherein the ratio is / 20 to 20/80. 5. An elastomer excellent in oil absorption in the surface layer and the inner layer is made of hydrogenated styrene-butadiene rubber 100.
2. A mixture of 20 to 250 parts by weight based on parts by weight.
Or the slush-molded skin according to 2. 6. An elastomer having excellent oil absorbing ability is a styrene / ethylene propylene / styrene block copolymer (S)
EPS), styrene / ethylene / butylene / styrene block copolymer (SEBS), olefin crystal / ethylene / butylene / olefin crystal block copolymer, ethylene / propylene rubber, and ethylene / octene copolymer. The slush-molded skin according to claim 5. 7. In the surface layer and the inner layer, the process oil is added in an amount of 5 parts by weight per 100 parts by weight of the elastomer having excellent oil absorbing ability.
The slush molded skin according to claim 1 or 2, which is mixed in an amount of from 200 to 200 parts by weight. 8. The method according to claim 1, wherein the internal release agent in the surface layer contains 0.1 to 5.0% by weight of at least one selected from dimethylsiloxane, methylhydroxypolysiloxane and methylphenylpolysiloxane. Slash molded skin. 9. The adhesion improver in the inner layer is at least one selected from an acid-modified polypropylene, a hydroxyl group-containing polypropylene, a hydroxyl group-terminated hydrogenated polypropylene, and a hydrolyzate of an ethylene / vinyl acetate copolymer.
The slush-molded skin according to claim 1 or 2, comprising 2 to 20% by weight of at least one kind of polymer. 10. A molded product having a slush molded skin comprising a laminate obtained by interposing a foamed layer between a slush molded skin composed of at least a surface layer and an inner layer obtained by powder slush molding and a core material composed of a synthetic resin. The slush molded skin is at least a polypropylene resin as a surface layer, and hydrogenated styrene butadiene rubber,
Process oil, an elastomer having excellent oil absorbing ability, and slush molding of a thermoplastic elastomer composition powder comprising an internal mold release agent, and further as at least a polypropylene resin, a hydrogenated styrene-butadiene rubber, and a process oil as its inner layer. A molded product having a slush-molded skin, which is a composite skin obtained by slush-molding a powder containing an elastomer having excellent oil-absorbing ability, an adhesion improver, and a thermoplastic polyurethane elastomer. 11. A powder of a thermoplastic elastomer composition containing at least a polypropylene resin as an inner layer, a hydrogenated styrene-butadiene rubber, a process oil, an elastomer having excellent oil absorption ability, and an adhesion improver, and a thermoplastic polyurethane elastomer. The molded product with a slush molded skin according to claim 10, wherein the mixed powder with the powder is slush molded. 12. The molded product with a slush molded skin according to claim 10, wherein the foamed layer is a polyurethane foam. 13. The molded product with a slush molded skin according to claim 10, wherein the core material is an olefin-based resin.