JP2002363350A - Skin composition for molded article integrated with skin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize the adhesion of a skin composition to a urethane resin while a TPO is used as the main constituent. SOLUTION: This skin composition is characterized in that it contains a main constituent comprising a thermoplastic polyolefin(TPO) and an auxiliary constituent, blended in a prescribed amount, comprising a thermoplastic polyolefin grafted with a functional urethane group (a TPO grafted with a functional urethane group). This TPO grafted with a functional urethane group consists of a main chain comprising a TPO and a side chain bonded to the main chain and having a functional urethane group on a part thereof. Since the functional urethane group as a polar group in the TPO grafted with a functional urethane group serves to moderate the nonpolarity of the main constituent comprising a TPO, the compatibility of the composition with a urethane resin having a urethane group as its polar group is enhanced so that the adherence to the urethane resin is revealed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composition for a skin of an integrally molded skin used as an interior part of a vehicle or the like, and more particularly to a composition for a skin of an integrally molded skin containing thermoplastic polyolefin as a main component.

[0002]

2. Description of the Related Art A skin integral molded product used as an interior component such as an instrument panel (instrument panel), a door trim, and a center console of an automobile is formed of a hard resin base material and foam molding on the surface of the resin base material. A foamed layer made of a material such as polyurethane foam, and a molded skin covering the surface of the foamed layer. According to this configuration, the rigidity can be ensured by the resin base material, the design can be enhanced by the molded skin, and the soft feeling can be imparted by the foamed layer.

[0003] In order to manufacture such a molded article integrally formed with a skin, a resin substrate and a molded skin, each of which is formed in a predetermined shape in advance, are arranged in a foaming mold, and a molded product is placed between the molded skin and the resin substrate. In general, a method of integrating three layers by injecting a foam material and performing foam molding is generally used. As the resin base material, one formed into a predetermined shape by injection molding or the like from acrylonitrile / styrene copolymer or polycarbonate / ABS alloy is used. The molded skin is
What has been formed into a predetermined shape by vacuum forming from a thermoplastic resin sheet or the like, or formed into a predetermined shape by powder slush forming has been used. The use of the powder slush molding method has the advantages that the number of steps for manufacturing a thermoplastic resin sheet can be reduced and that a complicated shape can be relatively easily molded.

[0004] As a material for the skin of automobile interior parts, a vinyl chloride resin has been frequently used. However, since the vinyl chloride resin contains a large amount of a plasticizer, there is a problem that bleeding of the plasticizer easily occurs. In addition, there is also a disadvantage that the skin is colored when high temperature acts due to the influence of the amine-based catalyst used in forming the foamed layer.

Therefore, in recent years, the use of a thermoplastic polyolefin (hereinafter, appropriately referred to as “TPO”) as a skin material has been studied. TPO has little deterioration and is stable, and has moderate flexibility. Then, like the vinyl chloride resin, the skin can be easily formed by powder slush molding using TPO powder. In addition, TPO has been attracting attention as an alternative material to vinyl chloride resins because it is friendly to the global environment and has excellent recyclability and light weight.

[0006]

However, TPO is a non-polar resin, and is incompatible with a urethane resin having a polar group. For this reason, even if the molded skin formed of TPO is arranged in a mold and the urethane foam layer is foam-molded, it is difficult to adhere the foam layer and the molded skin. Therefore, it is necessary to apply an adhesive in advance to the back surface of the molded skin in order to securely adhere the molded skin formed of TPO and the foamed layer, and the cost associated with an increase in the number of processes and material costs is required. Up problem occurs.

The present invention has been made in view of the above-mentioned circumstances, and it is an object of the present invention to provide a composition for a skin of a skin-integrated molded article which contains TPO as a main component and can be bonded to a urethane resin. It is a technical issue.

[0008]

According to a first aspect of the present invention, there is provided a composition for a skin of a skin-integrated molded article, wherein the main chain comprises a thermoplastic polyolefin as a main component, a thermoplastic polyolefin, and the main chain. And a side chain partially having a urethane functional group bonded thereto, and containing a predetermined amount of a urethane functional group-grafted thermoplastic polyolefin as an auxiliary component.

According to a second aspect of the present invention, there is provided a composition for a skin of a skin-integrated molded article, comprising a thermoplastic polyolefin as a main component and a thermoplastic polyester blended in a predetermined amount as an auxiliary component. It is assumed that.

According to a third aspect of the present invention, there is provided a skin-integrated molded article for a skin comprising a thermoplastic polyolefin as a main component, a main chain composed of the thermoplastic polyolefin, and maleic anhydride bonded to the main chain. And maleic anhydride-grafted thermoplastic polyolefin blended in a predetermined amount as an auxiliary component.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The skin composition of the skin integral molded article of the present invention contains TPO as a main component. The TPO may include at least an olefin-based elastomer from the viewpoint of imparting a certain degree of flexibility to the skin itself, and may also include an olefin-based resin as needed. Examples of the olefin-based elastomer include hydrogenated styrene-butadiene rubber and ethylene-propylene copolymer rubber (EPR, EPM, EPDM). In addition, examples of the olefin-based resin include crystalline polypropylene (crystalline PP), amorphous polypropylene (amorphous PP), and ethylene / octene copolymer. In addition, it is of course possible to add a plasticizer such as process oil or an internal release agent, if necessary.

(1) The skin composition of the skin-integrated molded article according to the first aspect comprises a main chain composed of a thermoplastic polyolefin, and a side chain bonded to the main chain and partially having a urethane functional group. Urethane functional group grafted thermoplastic polyolefin (hereinafter referred to as "urethane functional group graft TP"
O ") is blended in a predetermined amount as an auxiliary component.

The urethane functional group-grafted TPO compounded as an auxiliary component has a side chain partially containing a urethane functional group,
It is bonded to the main chain of TPO by grafting.
The urethane functional group as a polar group in the urethane functional group-grafted TPO alleviates the non-polarity of TPO as a main component. Then, by reducing the non-polarity of TPO, compatibility with a urethane resin having a urethane group as a polar group increases. For this reason, the composition for skin according to claim 1, wherein the urethane functional group-grafted TPO is blended as an auxiliary component, exhibits adhesiveness to the urethane resin.

Further, urethane resins are known as resins having excellent wear resistance. This is thought to be due to excellent monoforge. For this reason, by mixing a urethane functional group-grafted TPO with a grafted urethane functional group, an improvement in wear resistance of the skin material can be expected.

Here, the above urethane functional group graft TP
The main chain constituting O is made of a thermoplastic polyolefin.
The TPO constituting the main chain and the TPO serving as the main component of the composition for skin of the present invention may be the same or different. However, it is preferable to use the same one in consideration of recyclability. When TPO containing PP and EPDM is used as the main component of TPO, EPO is used as the TPO constituting the main chain of the urethane functional group-grafted TPO.
It is preferable to use PDM. The use of TPO as the main chain of the urethane functional group-grafted TPO is advantageous in terms of recyclability.

On the other hand, the side chain bonded to the main chain composed of TPO partially has a urethane functional group. The side chain is not particularly limited as long as it has a urethane functional group, and another functional group such as a hydroxyl group or a carboxyl group may be contained in the side chain. Also, the number of urethane functional groups contained in the side chain is not particularly limited, and may be one or two or more. Further, a urethane functional group may be directly bonded to the main chain composed of TPO, or a urethane functional group may be indirectly bonded via an alkyl group or an aromatic group. Non-yellowing type such as isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI) and dicyclohexylmethane diisocyanate (HNDI) as a side chain containing at least a part of such a urethane functional group, specifically, as an isocyanate. While using isocyanate, as a polyol, 1.6-hexanediol (1.6HG), ethylene glycol (EG) or butylene glycol (1.4) is used.
Average molecular weight of 500 to 10 using a diol such as BG)
000 polyurethane or the like can be suitably used.

In addition, polar functional groups other than urethane functional groups,
For example, even when a chlorine group, a hydroxyl group, a carboxyl group, or an epoxy group is grafted, the non-polarity of TPO as a main component can be reduced. However, these polar functional groups other than the urethane functional group have a certain degree of compatibility with the urethane resin, but do not reach the urethane functional group itself,
When a urethane functional group is grafted, it is advantageous in terms of compatibility with the urethane resin and development of stronger hydrogen bonds.

In the production of the urethane functional group-grafted TPO, a method based on a hydrogen abstraction reaction with an organic peroxide can be used, but from the viewpoint of increasing the graft ratio of the functional group, a reactive extrusion method must be used. Is desirable. For example, TPO, styrene monomer (SM)
Such as aromatic vinyl monomers, urethane functional monomers,
The urethane functional group-grafted TPO can be produced by mixing an organic peroxide and a stabilizer and performing reactive extrusion with an extruder such as a twin-screw extruder.

The urethane functional group-grafted TPO
In the above, the graft ratio of the urethane functional group to TPO is preferably about 1 to 20 mass%, particularly preferably about 8 to 12 mass%. When the graft ratio is less than 1 mass%, it is difficult to obtain the above-described effects by the urethane functional group. On the other hand, the technical limit when using the reactive extrusion method is 10 mass%.
Before and after. If the reaction time is longer, the graft ratio can be increased, but the longer the reaction time, the longer the extruder length, and the longer the physical length of the extruder, there is a limit. There is a limit to prolonging the reaction time due to the fact that there is a risk of side reactions such as decomposition of the TPO polymer. The graft ratio can also be increased by mixing a styrene-based resin, but the styrene-based resin is inferior in light resistance as compared with TPO, and thus is not suitable as a material for a skin material of a skin-integrated molded product. And cannot put much in. Therefore, the upper limit of the graft ratio is preferably about 20 mass%, and particularly preferably about 12 mass%.

The graft ratio was determined by using an infrared spectrometer manufactured by JASCO Corporation and comparing the peak ratio of each absorbance corresponding to the methyl group and the urethane functional group of TPO with a calibration curve. Can be calculated.

The compounding of the urethane functional group-grafted TPO as a sub-component with the TPO as a main component can be performed in a molten state or in a solid state such as a powder.
The mixing ratio of the urethane functional group-grafted TPO as a sub-component to the TPO as a main component is 1 to 30 m.
ass%, preferably 10 to 20mass
It is particularly preferred to be about s%. When the blending ratio of the urethane functional group-grafted TPO is less than 1 mass%, it is difficult to obtain the above-described effects by the urethane functional group. On the other hand, since urethane is a different molecule from TPO, it is preferable that urethane is as small as possible in consideration of recyclability. Further, the production cost of the urethane functional group-grafted TPO is high, which leads to an increase in cost. Therefore, the upper limit of the mixing ratio of the urethane functional group-grafted TPO is 30 m.
It is preferably about ass%, particularly preferably about 20 mass%.

(2) The skin composition of the skin-integrated molded article according to claim 2 contains a predetermined amount of a thermoplastic polyester as an auxiliary component.

The thermoplastic polyester blended as an auxiliary component has an ester group as a polar group. The ester group as the polar group reduces the non-polarity of TPO as the main component. Then, by reducing the non-polarity of TPO, compatibility with a urethane resin having a urethane group as a polar group increases. Therefore, the functional group grafted TPO
The composition for skin according to claim 2, wherein is blended as an auxiliary component, exhibits adhesiveness to a urethane resin.

Further, polyester is known as a resin having excellent wear resistance. This is thought to be due to excellent monoforge. For this reason, by incorporating polyester, an improvement in wear resistance of the skin material can be expected.

Examples of the thermoplastic polyester include thermoplastic polyether ester elastomers, thermoplastic polyester ester elastomers, and polycarbonate (P
C), polybutylene terephthalate (PBT), polyethylene terephthalate (PET) and the like can be employed.

In the case of blending the thermoplastic polyester with TPO as a main component, both can be mixed in a molten state or a solid state such as a powder. In addition, T as a main component
The mixing ratio of the thermoplastic polyester to PO is 1 to
It is preferable to set it to about 50 mass%,
It is particularly preferable to be about mass%. If the blending ratio of the thermoplastic polyester is less than 1 mass%, the above-mentioned effects of the thermoplastic polyester cannot be obtained.
On the other hand, since the thermoplastic polyester is a different molecule from TPO, it is preferable that the thermoplastic polyester be as small as possible in consideration of recyclability. Therefore, the upper limit of the blending ratio of the thermoplastic polyester is preferably about 50 mass%, particularly preferably about 20 mass%.

(3) The skin composition of the skin-integrated molded article according to claim 3, comprising a main chain composed of a thermoplastic polyolefin and a side chain bonded to the main chain and having at least a part of maleic anhydride. A maleic anhydride-grafted thermoplastic polyolefin (hereinafter, appropriately referred to as “maleic anhydride-grafted TPO”) is blended in a predetermined amount as an auxiliary component.

In the maleic anhydride-grafted TPO compounded as an auxiliary component, a side chain containing at least a part of maleic anhydride is bonded by grafting to a main chain composed of TPO. The maleic anhydride in the maleic anhydride grafted TPO has a hydroxyl group as a polar group. The hydroxyl group as a polar group reduces the non-polarity of TPO as a main component. Then, by reducing the non-polarity of TPO, compatibility with a urethane resin having a urethane group as a polar group increases. For this reason, the skin composition according to claim 3, wherein the maleic anhydride-grafted TPO is blended as an auxiliary component, exhibits adhesiveness to the urethane resin.

Here, the maleic anhydride grafted TP is used.
The main chain constituting O is made of a thermoplastic polyolefin.
The TPO constituting the main chain and the TPO serving as a main component of the skin composition of the present invention are the same as or different from the urethane functional group-grafted TPO in the skin composition according to claim 1. However, it is optimal to use the same one. In addition, PPO as a main component is PPO.
When a material containing P and EPDM is used, it is preferable to use PP as the TPO constituting the maleic anhydride-grafted TPO.

The maleic anhydride grafted TPO
As in the case of the urethane functional group-grafted TPO in the skin composition according to claim 1, a method using a hydrogen abstraction reaction with an organic peroxide can be used, but from the viewpoint of increasing the graft ratio of the functional group, It is desirable to utilize the reactive extrusion method described above.

On the other hand, the side chain bonded to the main chain composed of TPO has at least a part of maleic anhydride. The side chain is not particularly limited as long as it has maleic anhydride at least in part, and may be composed of maleic anhydride alone, or may include a functional group such as a hydroxyl group or a carboxylic acid group in the side chain. May be. Further, the number of maleic anhydrides contained in the side chain is not particularly limited, and may be one or two or more. Further, for the main chain composed of TPO,
The maleic anhydride may be directly bonded, or the maleic anhydride may be indirectly bonded via an alkyl group or an aromatic group.

Further, the maleic anhydride-grafted TPO
In the above, the graft ratio of maleic anhydride to TPO is 1 to 20 mass in the same manner as the urethane functional group-grafted TPO in the composition for skin according to claim 1.
%, Preferably about 8 to 12 mass%.

The graft ratio was determined by using an infrared spectroscopic analyzer manufactured by JASCO Corporation by comparing the ratio of the peaks of the absorbances corresponding to the methyl group of TPO and maleic anhydride with the calibration curve. Can be calculated.

The maleic anhydride-grafted TPO as a subcomponent with respect to the TPO as a main component can be mixed in a molten state or a solid state such as a powder.
The mixing ratio of maleic anhydride grafted TPO as a sub-component to TPO as a main component is 1 to 30 m.
ass%, preferably 10 to 20mass
It is particularly preferred to be about s%. If the blending ratio of the maleic anhydride-grafted TPO is less than 1 mass%, the above-mentioned effects due to maleic anhydride cannot be obtained. On the other hand, since maleic anhydride is a different molecule to TPO, it is preferable that maleic anhydride be as small as possible in consideration of recyclability. Further, the maleic anhydride-grafted TPO has a high production cost, which leads to an increase in cost. Therefore, the upper limit of the blending ratio of the maleic anhydride-grafted TPO is preferably about 30 mass%,
It is particularly preferred to be about s%.

The skin composition of the skin-integrated molded article of the present invention can be prepared, for example, as a mixed powder of a powder composed of a main component and a powder composed of subcomponents, or as a powder of a composite component composed of main components and subcomponents. Can be used for use. Then, the powder comprising the skin composition of the present invention is formed into a predetermined shape by a powder slush molding method, or once formed into a sheet shape and then formed into a predetermined shape by vacuum forming, for example, into an instrument panel. , Consoles, door trims, etc. can be used as molded skins for automotive interior materials.

[0036]

The present invention will be described below in detail with reference to examples.

[First Embodiment] In this embodiment, the composition for the skin of the integrally molded skin according to the first aspect is embodied.

Example 1 The composition for the skin of the present example was
It is composed of TPO blended as 90% by mass as a main component and urethane functional group grafted TPO blended as 10% by mass as an auxiliary component.

This composition for skin was produced as follows.

First, as a main component of the skin composition of this example, "Milastomer (registered trademark) 5030" (EPDM as an olefin elastomer, manufactured by Mitsui Chemicals, Inc.)
And PP as an olefin-based resin).

On the other hand, the urethane functional group-grafted TPO which is a subcomponent of the skin composition of the present embodiment is composed of a main chain composed of an ethylene / propylene copolymer rubber as a TPO, and a urethane resin bonded to the main chain. And a side chain consisting of The urethane resin constituting the side chain has an average molecular weight of 1000 using non-yellowing type IPDI as the isocyanate and 1.6HG as the polyol. The urethane functional group-grafted TPO was produced using a reactive extrusion method as described below.

That is, a twin-screw extruder (38 mm in diameter,
L / D38), using ethylene-propylene copolymer rubber as TPO as a main chain, di-tert-butyl peroxide 1 mass as an organic peroxide
% And 14 mass% of the urethane resin as a side chain were mixed and extruded at 190 ° C. to produce the urethane functional group-grafted TPO. In addition, the obtained urethane functional group grafted TPO has a graft ratio of the urethane resin of 12 mass%.

TPO 90 mass% thus obtained
And 10 mass% of a urethane functional group-grafted TPO are uniformly mixed by a twin-screw extruder to form pellets of about 2 mm, and then freeze-pulverized to powder having an average particle size of about 150 μm. did.

From the powder as the skin composition, a molded skin (1 mm thick) of an interior material for automobiles (instrument) was formed by a powder slush molding method.

Then, the obtained molded skin is arranged along one mold surface of the foaming mold, and a resin base material formed into a predetermined shape by injection molding from glass fiber reinforced acrylonitrile / styrene resin is foamed. It was arranged on the other mold surface of the mold. After the mold is closed, a predetermined amount of urethane foam resin is injected between the molded skin and the resin base material to perform foam molding, and the resin base material, the urethane foam resin, and the molded skin are integrated, and a skin integrated molded product is formed. And

Example 2 The composition for the skin of the present example was
The above-mentioned Example was composed of a TPO blended with 80 mass% as a main component and a urethane functional group-grafted TPO blended with 20 mass% as an auxiliary component. Same as 1.

In the same manner as in Example 1, a molded skin was formed from the powder as the skin composition, and
An integrated skin product was manufactured.

[Second Embodiment] In this embodiment, the composition for the skin of the integrally molded skin according to the second aspect is embodied.

Example 3 The composition for the epidermis of the present example was
75 mass% TPO powder as a main component,
It is composed of a mixed powder with a thermoplastic polyester powder blended as 25 mass% as an auxiliary component.

This skin composition was produced as follows.

First, the same TPO powder as in Example 1 was prepared as the main component of the skin composition of this example.

On the other hand, as a thermoplastic polyester powder as an auxiliary component of the skin composition of this example, “Hytrel (registered trademark) 3548L” (a thermoplastic polyether ester elastomer manufactured by Toray Dipon Co., Ltd .;
0 μm).

Then, 75 mass% of the TPO powder and 25 mass% of the thermoplastic polyester powder were uniformly mixed to obtain a skin composition of this example.

Then, in the same manner as in Example 1, a molded skin was formed from the mixed powder as the above-mentioned skin composition, and an integral skin molded article was produced.

Example 4 The composition for the skin of the present example was
TPO powder blended as 50 mass% as a main component,
This is the same as Example 3 except that it is composed of a mixed powder with a thermoplastic polyester powder mixed with 50 mass% as an auxiliary component, and the mixing ratio with the TPO powder thermoplastic polyester powder is different.

Then, in the same manner as in Example 1, a molded skin was formed from the mixed powder as the above-mentioned skin composition, and an integrally molded skin product was produced.

[Third Embodiment] In this embodiment, the composition for the skin of the integrally molded skin according to the third aspect is embodied.

Example 5 The composition for the epidermis of this example was
It is composed of TPO blended as 90% by mass as a main component and maleic anhydride grafted TPO blended as 10% by mass as an auxiliary component.

The composition for skin was produced as follows.

First, the same TPO as in Example 1 was prepared as the main component of the skin composition of this example.

On the other hand, the maleic anhydride-grafted TPO powder, which is a sub-component of the skin composition of this example, has a main chain of polypropylene as TPO and a side chain of maleic anhydride bonded to the main chain. Consists of This maleic anhydride-grafted TPO powder was produced using a reactive extrusion method as described below.

That is, a twin-screw extruder (38 mm in diameter,
L / D38), using polypropylene as the TPO as the main chain and di-ter as the organic peroxide.
While mixing 6 mass% of t-butyl peroxide and 12 mass% of maleic anhydride as a side chain,
The maleic anhydride-grafted TPO was produced by reactive extrusion at 20 ° C. The resulting maleic anhydride-grafted TPO has a graft ratio of maleic anhydride of 10 mass%.

The TPO 90 mass% thus obtained
And 10 mass% of maleic anhydride-grafted TPO are uniformly mixed by a twin-screw extruder to form pellets of about 2 mm, and then freeze-pulverized to a powder having an average particle size of about 150 μm. did.

In the same manner as in Example 1, a molded skin was formed from the powder as the skin composition, and
An integrated skin product was manufactured.

Example 6 The composition for the skin of this example was
The above-mentioned Examples consisted of TPO blended with 80 mass% as the main component and maleic anhydride grafted TPO blended with 20 mass% as the sub-component, except that the blending ratio between TPO and maleic anhydride grafted TPO was different. Same as 5.

Then, in the same manner as in Example 1, a molded skin was formed from the powder as the skin composition, and
An integrated skin product was manufactured.

(Comparative Example 1) In this comparative example, the same TPO powder (“Milastermer (registered trademark) 5
030 ") alone, and a skin-integrated molded article was produced in the same manner as in Example 1.

(Comparative Example 2) In this comparative example, a molded skin was formed from a vinyl chloride resin powder, and a skin-integrated molded article was produced in the same manner as in Example 1.

(Evaluation) Examples 1 to 6 and Comparative Examples 1 to 6
The peel strength between the molded skin and the urethane foam resin was evaluated for the integrally molded skin product obtained in 2.

This is to cut out a 25 mm wide test piece,
This test piece was measured at a speed of 200 mm / min by measuring the peel strength when the molded skin and the urethane foam resin were peeled by 180 degrees. Table 1 shows the results. In addition,
In Table 1, material failure (cohesive failure) means that a fracture has occurred in the urethane foam resin, and interfacial peeling means that the material has peeled off at the interface between the molded skin and the urethane foam resin.

[0071]

[Table 1]

As is clear from Table 1, Examples 1 to 6 in which a predetermined amount of a predetermined subcomponent was mixed with TPO as a main component were used.
According to the composition for skin, the peel strength almost equal to that of the vinyl chloride resin could be secured. On the other hand, in Comparative Example 1 in which a molded skin composed only of TPO was formed, good adhesion between the molded skin and the urethane foam resin could not be secured.

Accordingly, it was confirmed that the adhesion to the urethane foam resin was remarkably improved by mixing a predetermined amount of the predetermined subcomponent with TPO as the main component.

[0074]

As described in detail above, according to the composition for a skin of a skin-integrated molded article of the present invention, reliable adhesion to a urethane resin can be achieved while using TPO as a main component. For this reason, it becomes possible to provide a molded skin using TPO which is friendly to the global environment and is advantageous in terms of recycling and weight reduction.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C08L 67:00) (C08L 23/00 23:26) (72) Inventor Naoki Ohshita Toyota, Toyota City, Aichi Prefecture No. 1 town Toyota Motor Corporation F term (reference) 4J002 AC111 BB151 BB212 BB282 CF102 GN00

Claims (3)

[Claims] 1. A thermoplastic polyolefin as a main component, comprising a main chain composed of a thermoplastic polyolefin, and a side chain bonded to the main chain and having a urethane functional group in part,
A composition for a skin of a skin-integrated molded article, comprising a urethane functional group-grafted thermoplastic polyolefin compounded in a predetermined amount as an auxiliary component. 2. A composition for the skin of a skin-integrated molded article, comprising a thermoplastic polyolefin as a main component and a thermoplastic polyester blended in a predetermined amount as an auxiliary component. 3. A thermoplastic polyolefin as a main component, a main chain of the thermoplastic polyolefin, and a side chain bonded to the main chain and having at least a part of maleic anhydride, and are mixed in a predetermined amount as an auxiliary component. A composition for a skin of an integrated skin product, comprising a maleic anhydride-grafted thermoplastic polyolefin.