JP2000006318A - Molding sheet of thermoplastic elastomer skin for interior of car, and production thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the subject molding sheet excellent in solvent resistance and generating no thermal discoloration without requiring a surface oxidizing treatment process such as corona treatment. SOLUTION: A molding sheet of a thermoplastic elastomer skin for an interior of a car is constituted by applying topcoating to the surface of a thermoplastic elastomer sheet comprising a blend of crystalline polyolefin and an olefinic elastomer through a primer based on a polyolefinic resin to which 2 mg equivalent/g or less of a hydroxyl or carboxyl group is added. In this case, embossing processing is applied to the surface of the topcoating at 190 deg.C or higher.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet for forming a matte-surface-coated thermoplastic elastomer skin suitable for use as a decorative skin of interior parts for automobiles, and a method for producing the same. The present invention relates to a sheet for molding a thermoplastic elastomer skin obtained by applying a resin primer and a method for producing the same.

[0002]

2. Description of the Related Art Interior parts such as instrument panels of automobiles must not only be integrally formed into a complicated shape, but also have good feel such as flexibility and elasticity, and have a surface having a good feeling. It must be in a matte state such as squeezing. Therefore, conventionally, a foamed layer is provided between a base material of an interior part such as an instrument panel and a skin layer, and the surface of the skin layer is subjected to squeezing or matte coating.

[0003] Conventionally, the skin of interior parts has a touch, abrasion resistance,
In consideration of weather resistance, durability and the like, it is formed of a polyvinyl chloride resin, and the internal foam layer is mainly formed of a polyurethane foam. The base material is moldable,
Considering strength and durability, polypropylene and ABS
It was formed of resin or the like. Since the conventional interior parts having such a laminated structure are made of different resins, it is necessary to separate each resin when recycling. However, it is not only time-consuming to separate the polyvinyl chloride resin skin layer and the ABS resin or polypropylene base material adhered by the polyurethane foam layer, but also the cross-linked foam polyurethane layer cannot be reused. There was a problem. In addition, since gases that adversely affect the environment are generated at the time of incineration of polyvinyl chloride resin, it must be incinerated by a large incinerator equipped with environmental measures. For this reason, interior parts of automobiles are finely crushed and then disposed of at a disposal site as dust.

[0004] In view of recent garbage problems and environmental problems, recycling of interior parts has been strongly desired in order to reduce waste materials generated from automobiles as much as possible, and some implementations have been attempted. For that purpose, it is preferable to unify the resin components of each layer to those of the same system, particularly to a polyolefin resin.
If the skin of the interior part is made of a thermoplastic polyolefin resin, the coatability is reduced. Therefore, it is necessary to apply a primer to the surface or perform a corona discharge treatment. In addition, in consideration of production efficiency, a surface-coated skin sheet is prepared in advance,
In addition, it is common to bond and laminate a polypropylene foam and a base sheet, and vacuum form them.

[0005] Chlorinated polypropylene coatings and reactive coatings containing saturated polyesters and polyisocyanates are known as primers for coating the surface of a skin sheet made of a thermoplastic polyolefin resin. Apply a reactive paint containing saturated polyester resin and polyisocyanate to the surface of the skin sheet coated with a chlorinated polypropylene primer or the surface of the skin sheet that has been subjected to corona discharge treatment. A method of applying a paint containing a resin or the like, a paint obtained by adding a polyisocyanate thereto, or a polyurethane paint has been proposed.

[0006] Specifically, for example, Japanese Patent Application Laid-Open No. Sho 60-197741 discloses a method for producing a sheet used for the skin of an instrument panel or the like among automotive interior materials. Forming a sheet from a raw material containing an α-olefin-based copolymer, and applying a reactive paint containing a saturated polyester resin, an acrylate resin and an isocyanate resin to the surface of the sheet; A manufacturing method is disclosed.

[0007] Japanese Patent Publication No. 7-14655 discloses a car ceiling,
A method for producing a printed composite sheet for a skin used for a door rim or the like, comprising applying a chlorinated polypropylene primer to one surface of a skin sheet made of a thermoplastic elastomer such as a polypropylene elastomer, and then applying an acrylic resin Printing with an ink composition in which the ink is blended with a mixed processing agent comprising a polyester resin and a saturated polyester resin, and the resulting skin sheet made of a thermoplastic elastomer with printing is fused onto one or both sides of a pad made of a polypropylene foam. Disclosed is a method of unifying and integrating.

Further, Japanese Patent No. 2533147 discloses that (a) 90 to 20 parts by weight of an ethylene / α-olefin copolymer rubber, and (b)
10 to 80 parts by weight of polyolefin resin (however, (a) + (b) =
100 parts by weight), and if necessary, (c) a peroxide non-crosslinked hydrocarbon-based rubber-like substance, and (d) a mineral oil-based softener 0 to 200.
Parts by weight of a partially crosslinked copolymer rubber composition (I) 100 obtained by dynamically heat-treating the mixture comprising
Selected from saturated polyesters and chlorinated polyolefins, on the surface of a thermoplastic elastomer molded product consisting of up to 30 parts by weight and 0 to 70 parts by weight of a polyolefin resin (II) (100 parts by weight of (I) + (II)). A primer layer containing at least one compound is provided, and on this primer layer,
Topcoat layer containing at least one compound selected from saturated polyester, acrylate resin, polyvinyl chloride and isocyanate resin (however, when the primer layer is composed of only saturated polyester, the topcoat layer is at least an acrylate ester (Including a resin) is disclosed.

[0009]

In JP-A-60-197741 and JP-B-7-14655, a chlorinated polyolefin resin such as chlorinated polypropylene is used as a primer. However, when a chlorinated polyolefin resin is used as a primer, it has poor durability against hydrocarbon solvents such as petroleum benzene, volatile oil, etc. It has the disadvantage of causing discoloration.

[0010] Japanese Patent Application Laid-Open No. Sho 60-197741 and Japanese Patent No. 253314
In No. 7, a reactive primer containing saturated polyester and polyisocyanate is used.However, when a reactive primer is used, the surface of the thermoplastic polyolefin resin sheet must be oxidized by corona discharge treatment or the like. The mixture of polyester and polyisocyanate cannot be stored due to the problem of heavy load on the process and the reactivity, so it cannot be reused at a later date, and all remaining liquids must be discarded. There is a problem that it does not.

As a result of various studies on the above problems, the following has been found. That is, the solvent resistance is because the chlorinated polypropylene itself is easily eroded by the hydrocarbon solvent. (2) Regarding thermal discoloration, chlorine generated when the chlorinated polypropylene is thermally decomposed Due to gas or hydrogen chloride gas. Furthermore, when a reactive primer containing a saturated polyester and a polyisocyanate is used, corona discharge treatment is required because a polar group such as a hydroxyl group which reacts with an isocyanate component in the primer is generated on the surface of the thermoplastic polyolefin resin sheet. Otherwise, the primer will not adhere and the residual liquid cannot be stored.The isocyanate component in the primer containing the saturated polyester and polyisocyanate reacts with the residual hydroxyl groups in the saturated polyester and the moisture in the air over time. This is because it does not react with the polar group on the surface of the thermoplastic polyolefin resin sheet.

[0012] Accordingly, an object of the present invention is to provide excellent solvent resistance without requiring a surface oxidation treatment step such as corona discharge treatment.
An object of the present invention is to provide a sheet for forming a skin of an interior part without thermal discoloration and a method for producing the same.

[0013]

Means for Solving the Problems As a result of intensive studies in view of the above-mentioned objects, the present inventor has found that in order to solve the above-mentioned problems, the present inventors have developed a one-pack of a chlorine-free, non-reactive modified polyolefin as a primer. The discovery that primers must be used led to the present invention.

That is, the sheet for molding a thermoplastic elastomer skin of the present invention is formed on the surface of the thermoplastic elastomer sheet via a primer mainly composed of a polyolefin resin to which a hydroxyl group or a carboxyl group is added at 2 mg equivalent / g or less. The top coat is painted, and the surface of the top coat is subjected to squeezing. The polyolefin resin for the primer is preferably a modified polypropylene obtained by random, block or graft copolymerization of an unsaturated ester or ether having an hydroxyl group in propylene or polypropylene or an unsaturated carboxylic acid. The thermoplastic elastomer is preferably a blend of a crystalline polyolefin and an olefin-based elastomer.

Further, the method for producing a sheet for molding a thermoplastic elastomer skin according to the present invention is characterized in that a primer mainly composed of a polyolefin resin to which a hydroxyl group or a carboxyl group is added at 2 mg equivalent / g or less is applied to the surface of the thermoplastic elastomer sheet. After the top coat is applied on the primer, a squeezing process is performed at 190 ° C. or higher from the surface of the top coat.

[0016]

According to the present invention, a thermoplastic elastomer sheet is coated with a primer mainly composed of polypropylene containing a hydroxyl group or a carboxyl group, coated with a top coat, and then squeezed at 190 ° C. or more. ,
Since the top coat and the thermoplastic elastomer sheet are completely thermally fused and integrated via the primer layer, there is no need to apply a surface oxidation treatment such as a corona discharge treatment to the thermoplastic elastomer sheet before applying the primer. In addition, since none of the layers contains chlorine, the finished elastomer skin material having excellent solvent resistance without thermal discoloration of the final product is obtained.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS [1] Layer Structure of Sheet for Molding Thermoplastic Elastomer The sheet for molding of the present invention comprises, in order from the bottom, a thermoplastic elastomer sheet, a primer layer and a top coat layer.

(A) Thermoplastic Elastomer Sheet The thermoplastic elastomer used in the present invention is preferably a blend of a crystalline polyolefin and an olefin elastomer. As the crystalline polyolefin, propylene homopolymer or ethylene, 1-butene, 1-pentene, 1-hexene, propylene having a copolymerized α-olefin such as 4-methyl-1-pentene as a main component Random or block copolymers are preferred. The melt flow rate (MFR, 230 ° C., 2.16 kg load) may be about 0.5 to 100 g / 10 minutes.

As the olefin-based elastomer,
Elastomers obtained by copolymerizing two or more monoolefins such as ethylene, propylene, 1-butene, 1-hexene, and 4-methyl-1-pentene are preferable, and specifically, ethylene-propylene copolymer rubber (EPR), ethylene-butene copolymer rubber (EBR), ethylene-propylene-diene copolymer rubber (EPDM) and the like are preferable.
Ethylene content in olefinic elastomer is 30-80
% By weight, and an iodine value (unsaturation degree)
Is preferably 30 or less, and the Mooney viscosity ML _{1 + 8} (127 ° C.) is preferably about 10 to 200. The crystallinity of such an olefin-based elastomer is usually 40% or less.

The weight ratio of the crystalline polyolefin to the olefin elastomer is preferably about 5/95 to 80/20. If the content of the crystalline polyolefin is less than 5% by weight (the content of the olefin-based elastomer exceeds 95% by weight), the mechanical strength decreases, while the content of the crystalline polyolefin is 80% by weight.
When it exceeds (when the olefin-based elastomer is less than 20% by weight), rubber-like physical properties decrease.

The thermoplastic elastomer is preferably at least partially crosslinked in order to have good mechanical strength, heat resistance, durability, weather resistance, abrasion resistance, impact resistance and the like. As the peroxide-based crosslinking agent that can be used for crosslinking of the thermoplastic elastomer, for example, dicumyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-
2,5-di (t-butylperoxy) hexane, t-butylperoxybenzoate, t-butylcumyl peroxide and the like. The amount of peroxide crosslinking agent added is 0.
It may be about 01 to 0.05 parts by weight. Further, a crosslinking aid may be added.

In the thermoplastic elastomer, if necessary,
An inorganic filler such as talc, calcium sulfate, barium sulfate, mica, calcium silicate, and the like may be blended in addition to an antioxidant, an ultraviolet absorber, an antistatic agent, a flame retardant, and a pigment.

The thickness of the thermoplastic elastomer sheet is 0.3 m
m or more, more preferably 0.4 to 0.8 mm. The thickness of the thermoplastic elastomer sheet is 0.3
If it is less than mm, not only the mechanical strength and durability are not sufficient, but also it is difficult to prevent defects such as unevenness from being generated on the surface after the following vacuum forming step.

(B) Primer The primer used in the present invention is mainly composed of a polyolefin resin to which a hydroxyl group or a carboxyl group is added in an amount of 2 mg equivalent / g or less. To introduce a hydroxyl group or a carboxyl group into the polyolefin resin, a solution polymerization method, a suspension polymerization method, an emulsion polymerization method, a melt-kneading method in the presence of a peroxide, etc., can be used by any method, and a random polymer, Any of a block polymer and a graft polymer may be used. Among them,-(CH ₂ -CH (CH ₃ )) _m- (CH ₂ -CX (CH ₃ )) _n- (where X is a hydroxyl group or a carboxyl group, and m and n are the numbers of the respective structural units. ) Is preferred. In the case of a graft copolymer into which a hydroxyl group has been introduced, it can be obtained by melt-kneading polypropylene and an unsaturated ester or ether having a hydroxyl group in the presence of a peroxide. In the case of a graft copolymer having a carboxyl group introduced,
It can be obtained by melt-kneading polypropylene and an unsaturated carboxylic acid or its anhydride in the presence of a peroxide.

To introduce a hydroxyl group, a hydroxy group-containing (meth) acrylate such as hydroxymethyl (meth) acrylate, hydroxyethyl (meth) acrylate, hydroxybutyl (meth) acrylate, N-methylolacrylamide, etc. It is preferable to use, and particularly preferable is 2-hydroxyethyl (meth) acrylate and the like. In order to introduce a carboxyl group, it is preferable to use an unsaturated carboxylic acid or its anhydride. Examples of unsaturated carboxylic acids or anhydrides thereof include monocarboxylic acids such as acrylic acid and methacrylic acid, maleic acid, fumaric acid, dicarboxylic acids such as itaconic acid, maleic anhydride, and dicarboxylic anhydrides such as itaconic anhydride. Is mentioned.

The added amount of hydroxyl group or carboxyl group is 2 mg
Equivalent / g or less. The addition amount of the hydroxyl group or carboxyl group of 2 mg equivalent / g or less is sufficient, and if it exceeds that, no further improvement in the performance as a primer is obtained, and only the production cost increases. The preferred amount of the hydroxyl group or carboxyl group to be added is 0.5 to 1.5 mg equivalent / g.

The polyolefin resin containing a hydroxyl group or a carboxyl group is preferably a propylene-based resin, but may further contain a comonomer such as ethylene.

Primers based on a polyolefin resin containing a hydroxyl group or a carboxyl group are commercially available, for example, AD-456M (manufactured by Tokushou Shigyo Kogyo KK), Unistor P-801, P-401 (Mitsui Chemicals, Inc.) Co., Ltd.).

The coating amount of the primer is preferably 10 to 100 g / m ² (when wet). The coating amount of the primer is 10 g / m ²
If it is less than 30, the adhesion between the thermoplastic elastomer sheet and the top coat is insufficient, and even if it exceeds 100 g / m ² , it is meaningless. Since the thickness of the primer layer is reduced to about 1/10 by drying, the dried thickness is about 1 to 10 g / m ² .

(C) Topcoat Examples of resins for the topcoat paint include polyesters, acrylic resins, and polyisocyanates.

The polyester has a basic structure consisting of a polyhydric alcohol and a polybasic acid or its anhydride. Examples of the polyhydric alcohol include ethylene glycol, diethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, and polypropylene glycol. Examples of the polybasic acid or its anhydride include phthalic acid, phthalic anhydride, isophthalic acid, and terephthalic acid. Acid, maleic acid, maleic anhydride, fumaric acid, itaconic acid and the like. Alkyd or polyarylate may be used as the polyester.

The acrylic resin is a polymer of (meth) acrylates of methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl acrylate, or, if necessary, styrene. , Α-
Styrenes such as methylstyrene and carboxylic acids such as (meth) acrylic acid, crotonic acid, itaconic acid, fumaric acid and maleic acid are blended and copolymerized.

Examples of the polyisocyanate include aliphatic polyisocyanates such as hexamethylene diisocyanate (HMDI) and isophorone diisocyanate (IPDI).
And cycloaliphatic polyisocyanates such as diphenylmethane
And polyisocyanate compounds such as -4,4'-diisocyanate (MDI) and hydrogenated MDI.

In general, the thickness of the top coat is preferably from 3 to 20 μm, more preferably from 5 to 15 μm. If it is less than 3 μm, embossing such as graining cannot be performed satisfactorily, and it is difficult to increase the thickness to more than 20 μm by one coating.

[2] Production Method of Sheet for Forming (A) Production of Sheet for Skin It is preferable to form a sheet by melt-kneading the raw materials for the thermoplastic elastomer and extruding or calendering. Before applying the primer, the sheet is preferably subjected to a heat treatment or an ultraviolet irradiation treatment so as to be crosslinked. Crosslinking gives the sheet good heat resistance, weather resistance, durability, abrasion resistance, etc. without losing flexibility. The application of the primer and the application of the top coat to the thermoplastic elastomer sheet can be performed by a known method such as a roll coating method and a spray method.

The squeezing process is performed from the top coat surface to 19
0 ° C. or higher, preferably 190 to 240 ° C., especially 190 to 240 ° C.
Perform at a temperature of 210 ° C. The squeezing process gives a grain pattern such as leather to the surface of the top coat.

[3] Use of Forming Sheet The forming sheet of the present invention is suitable for use as a skin material for interior parts such as instrument panels. Here, an example of manufacturing interior parts by vacuum forming will be described. First, a foamed layer of a polypropylene resin and a base sheet of a polypropylene resin are respectively placed under a squeezed forming sheet via an olefin-based adhesive, and the whole is placed in a vacuum forming die. A vacuum is drawn from the substrate sheet side to form a predetermined shape. The vacuum forming temperature is preferably about 160 ° C.

[0038]

The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the invention is limited thereto.

In the examples, the following materials were used. (1) Thermoplastic elastomer sheet 0.6 mm thick, MFR (230 ° C, 2.16 kg load, JIS K7
210) is a thermoplastic elastomer sheet (polypropylene / olefin-based elastomer blend) of 1.04 g / 10 minutes.

(2) Primer and coating method AD-456M Chlorine-free modified polypropylene (carboxyl group content: 1.0 mg equivalent / g), one-pack type primer (manufactured by Tokusekisho Kogyo KK). AD-479 Chlorinated polypropylene primer (manufactured by Tokusekisho Kogyo Co., Ltd.). AD-180 Saturated polyester primer (manufactured by Tokusekisho Kogyo Co., Ltd.). UA-63 Polyisocyanate (Special Color Materials Co., Ltd.)
Made). Coating method: One-time application with a 120 mesh gravure roll coat (wet application amount: 18 to 22 g / m ² ).

(3) Topcoat and coating method PEX62-31 Urethane-based coating for topcoat (manufactured by Tokusekisho Kogyo KK). EK-167 Topcoat paint composed of saturated polyester, acrylic resin and polyvinyl chloride (weight ratio 30/60 /
10, Special Color Materials Co., Ltd.). EU-1000 Urethane-based paint for top coat (manufactured by Tokusekisho Kogyo Co., Ltd.). Coating method: Spray method (wet coating amount: 100 to 150 g /
m ^2).

Example 1 A chlorine-free modified polypropylene primer (AD-456M) was applied to the above thermoplastic elastomer sheet with a gravure roll of 120 mesh at an application amount of 18 to 22 g / m ² (when wet), and dried. was coated with the 100 ~150 g / m ² coating amount (wet) by spraying the coating material for the topcoat. After drying, embossing was performed at 200 ° C. to prepare Samples 1 to 3. Each sample was tested for adhesion, solvent resistance, and heat discoloration resistance in the following manner. Table 1 shows the results.

(1) Adhesion According to JIS D202, 10 × 10 grids were formed on the surface of the top coat of each sample at intervals of 2 mm with a stainless steel cutter, and cellophane tape (Nichiban LP24) was applied from above the grids. After sufficient pressure bonding with a roller, the sheet was vigorously peeled off, and the number of remaining grids was counted. The adhesiveness is represented by the number of uncut strips / 100.

(2) Solvent resistance A gakushin type friction discoloration tester type II specified in JIS L0823,
A polypropylene foam sheet (15025, manufactured by Toray Industries, Inc.) having a width of 3 cm and a length of 20 cm is placed, and a sample of the same size is set thereon with the top coat side facing upward, and a friction element is placed on the sample. (2 cm wide, 4 cm long white degreased flannel impregnated with a test solvent (white gasoline: toluene weight ratio = 9: 1)) was set, and at 10 cm intervals at 25 ° C. and 200 g load. 30 reciprocations at a speed of 1 reciprocal / 2 seconds, 30
After standing for more than a minute, the condition of the friction surface was observed with the naked eye or a magnifier of 10 times.

(3) Heat discoloration resistance A polypropylene foam sheet (manufactured by Toray Industries Co., Ltd., 15025) is placed on the sample with the top coat side facing out, suspended vertically in a gear oven, and rotated at 120 ° C. for 30 minutes.
After heating for 0 hour, apply a C light source to the top coat surface after heating using a color difference meter according to the yellowness measurement method (JIS K7103).
The tristimulus values X, Y, and Z were measured in a visual field, and the degree of yellowing was calculated from X, Y, and Z by the following equation. Yellowness (YI) = 100 (1.28X- 1.06Z) / Y yellowing _{(ΔYI) = YI 300 - YI} 0 YI 300 = yellowness YI ₀ = yellowness before the test after the test

Table 1 Sample No. 1 2 3 Primer AD-456M AD-456M AD-456M Topcoat EK-167 EU-1000 PEX62-31 Corona discharge treatment None None None Adhesion 100/100 100/100 100/100 Resistance Solvent ○ ○ ○ Heat discoloration 5.38 2.54 3.51

As is evident from Table 1, there was no problem in the adhesiveness and the solvent resistance of all the samples. As for the heat discoloration, it was found that when a urethane-based top coat with little thermal discoloration was used (samples 2 and 3), it was sufficiently practical. When a top coat composed of saturated polyester, acrylic resin and polyvinyl chloride was used (Sample 1), the coloring was slightly more noticeable than polyvinyl chloride, but the degree of discoloration was smaller than when chlorinated polypropylene was used as a primer. Close to practical level.

From the above, after a primer mainly composed of chlorine-free modified polypropylene was applied to the thermoplastic elastomer sheet and the top coat was applied, 190 to 210
Sheets for forming formed by drawing at a temperature of ℃ have extremely superior performance and ease of use compared to the conventionally used thermoplastic elastomer sheets coated with a primer mainly composed of chlorinated polypropylene. You can see that there is.

Comparative Example 1 Samples 4 to 11 of molding sheets were prepared in the same manner as in Example 1 except that a commercially available primer was used as the primer. Evaluation tests for adhesion, solvent resistance, and heat discoloration resistance were performed on the obtained Samples 4 to 11 in the same manner as in Example 1. Table 2 shows the results.

Table 2 Sample No. 4 5 6 7 ^* Primer AD-479 AD-479 AD-180 / AD-180 / UA-63 UA-63 Topcoat EK-167 EU-1000 EK-167 EK-167 Corona discharge Treatment No No Yes Yes Adhesive 100/100 100/100 100/100 0/100 Solvent resistance ×× × ○ − Thermal discoloration 8.48 6.82 6.71 −

Table 2 (continued) Sample No. 8 9 10 ^* 11 Primer AD-180 / AD-180 / AD-180 / AD-180 / UA-63 UA-63 UA-63 UA-63 Topcoat EK-167 EU-1000 EU-1000 EU-1000 Corona discharge treatment No Yes Yes No Adhesion 0/100 100/100 0/100 0/100 Solvent resistance-○--Heat discoloration-1.13--Note: * After mixing, the mixture was allowed to stand at 25 ° C. for 7 days and then applied.

As is clear from Table 2, when the chlorinated polypropylene primer was used (samples 4 and 5), there was no problem in the adhesiveness, but the durability to hydrocarbon solvents and the heat discoloration were remarkably poor, and the practicality was poor. poor. Further, as is clear from Samples 8 and 11, it was found that the reactive primer had no adhesion to the thermoplastic elastomer sheet without the corona discharge treatment. Further, as is clear from Samples 7 and 10, even when the thermoplastic elastomer sheet was subjected to corona discharge treatment,
It was found that good adhesion was not obtained when the reactive primer which had been allowed to stand at 25 ° C. for 7 days after mixing the two components was used. Only in the case of Samples 6 and 9 in which the reactive primer was applied immediately after the corona discharge treatment, both the adhesiveness and the solvent resistance were good, but when a mixed system of saturated polyester, acrylic resin and polyvinyl chloride was used as the top coat. As can be seen from the results of Sample 6, significant thermal discoloration occurred.

From the above, when a reactive primer is used, it is necessary to strictly control the storage temperature and time of the thermoplastic elastomer sheet after the corona discharge treatment and before applying the primer, and to select a paint for the top coat. Is also limited to a narrow range.

[0054]

According to the present invention, a thermoplastic elastomer sheet is coated with a primer mainly composed of a polyolefin resin to which a hydroxyl group or a carboxyl group is added, and then a top coat such as polyurethane is applied thereon, followed by pressing. Since the processing is performed, the thermoplastic elastomer sheet and the top coat are completely thermally fused and integrated via the primer. Therefore, it is not necessary to apply a surface oxidation treatment such as a corona discharge treatment to the thermoplastic elastomer sheet before applying the primer. In addition, since all the layers do not contain chlorine, the final product becomes a molding elastomer skin material excellent in solvent resistance without thermal discoloration and excellent in recyclability.

────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] September 21, 1999 (September 9, 1999
1)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claim 1

[Correction method] Change

[Correction contents]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] Claim 5

[Correction method] Change

[Correction contents]

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0001

[Correction method] Change

[Correction contents]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet for forming a matte-surface-coated thermoplastic elastomer skin suitable for use as a decorative skin of interior parts for automobiles, and a method for producing the same. Excellent recyclability by applying resin primer
The present invention relates to a molded sheet for thermoplastic elastomer skin and a method for producing the same.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0012

[Correction method] Change

[Correction contents]

Accordingly, an object of the present invention is to provide a sheet for forming a skin of an interior part which is excellent in recyclability and solvent resistance without heat discoloration without requiring a surface oxidation treatment step such as corona discharge treatment. And a method for producing the same.

[Procedure amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0014

[Correction method] Change

[Correction contents]

That is, the sheet for molding a thermoplastic elastomer skin of the present invention is formed on the surface of the thermoplastic elastomer sheet via a primer mainly composed of a polyolefin resin to which a hydroxyl group or a carboxyl group is added at 2 mg equivalent / g or less. Court has been painted, the top code
The thickness of the layer is 3 to 20 μm, and the surface of the top coat is squeezed to provide excellent recycling.
And having a le property. The polyolefin resin for the primer is preferably a modified polypropylene obtained by random, block or graft copolymerization of an unsaturated ester or ether having an hydroxyl group in propylene or polypropylene or an unsaturated carboxylic acid. The thermoplastic elastomer is preferably a blend of a crystalline polyolefin and an olefin-based elastomer.

[Procedure amendment 6]

[Document name to be amended] Statement

[Correction target item name] 0015

[Correction method] Change

[Correction contents]

Further, the method for producing a sheet for molding a thermoplastic elastomer skin having excellent recyclability according to the present invention comprises a polyolefin resin having a hydroxyl group or a carboxyl group added to the surface of the thermoplastic elastomer sheet in an amount of 2 mg equivalent / g or less. And apply the primer on the primer.
After applying a top coat having a thickness of 3 to 20 μm, a drawing process is performed at 190 ° C. or higher from the surface of the top coat.

[Procedure amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0016

[Correction method] Change

[Correction contents]

[0016]

According to the present invention, a primer mainly composed of a polypropylene containing a hydroxyl group or a carboxyl group is applied to a thermoplastic elastomer sheet, and a top coat having a thickness of 3 to 20 μm is applied. By squeezing at a temperature of ℃ or more, the top coat and the thermoplastic elastomer sheet are completely heat-sealed and integrated via the primer layer, so that surface oxidation treatment such as corona discharge treatment is performed before primer application. There is no need to apply it to the plastic elastomer sheet. Since any layer also contains no chlorine, it is assumed that the final product is Ri Do and that no solvent resistance excellent molding elastomeric skin material to heat discoloration, and excellent in recyclability
You .

[Procedure amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0034

[Correction method] Change

[Correction contents]

The thickness of the top coat is 3 to 20 μm .
The preferred thickness is 5 to 15 μm . If it is less than 3 μm, embossing such as graining cannot be performed satisfactorily, and it is difficult to increase the thickness to more than 20 μm by one coating.

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Keiichi Honjo 1-4-1, Chuo, Wako City, Saitama Prefecture Inside Honda R & D Co., Ltd. ) Inventor Manabu Kudo 1-63 Wakashiba, Kashiwa-shi, Chiba Pref. EJ652 GB33 JA11A JB07 JB16A

Claims (5)

[Claims] 1. The surface of a thermoplastic elastomer sheet,
A top coat is applied via a primer mainly composed of a polyolefin resin to which a hydroxyl group or a carboxyl group is added at 2 mg equivalent / g or less, and a squeezing process is performed on a surface of the top coat. Sheet for molding thermoplastic elastomer skin. 2. The sheet for molding a thermoplastic elastomer skin according to claim 1, wherein the polyolefin resin for a primer is a random, block or unsaturated ester or ether having a hydroxyl group in propylene or polypropylene or an unsaturated carboxylic acid. A sheet for molding a thermoplastic elastomer skin, which is a graft copolymerized modified polypropylene. 3. The sheet for molding a thermoplastic elastomer skin according to claim 2, wherein the modified polypropylene is a graft copolymer obtained by melt-kneading polypropylene and an unsaturated carboxylic acid or an anhydride thereof in the presence of a peroxide. A sheet for molding a thermoplastic elastomer skin, which is a polymer. 4. The thermoplastic elastomer skin sheet according to claim 1, wherein said thermoplastic elastomer is a blend of a crystalline polyolefin and an olefin-based elastomer. Elastomer skin molding sheet. 5. A method for producing a sheet for molding a thermoplastic elastomer skin, comprising applying a primer mainly composed of a polyolefin resin to which a hydroxyl group or a carboxyl group is added at 2 mg equivalent / g or less to the surface of the thermoplastic elastomer sheet, A method comprising applying a top coat on the primer and then squeezing the surface of the top coat at 190 ° C. or higher.