WO1992012008A1

WO1992012008A1 - Multilayered sheets having excellent adhesion

Info

Publication number: WO1992012008A1
Application number: PCT/US1991/009511
Authority: WO
Inventors: Richard Van Brooks; Edward Rudolph Hollander, Jr.; Michael Charles Carmody
Original assignee: Eastman Kodak Company
Priority date: 1991-01-02
Filing date: 1991-12-18
Publication date: 1992-07-23

Abstract

Disclosed are multilayered sheets, preferably formed by coextrusion, comprising an outer layer of a thermoplastic nylon or nylon blend, an outer layer of polyester or polyolefin, and a tie layer of a modified polyethylene or polypropylene. The sheets have excellent adhesion and are especially useful as a carrier for decorative and/or protective coatings.

Description

MULTILAYERED SHEETS HAVING EXCELLENT .ADHESION

Technical Field

This invention relates to multilayered films or sheets which have excellent adhesion. More particularly, the invention relates to multilayered sheets wherein a tie layer of a particular polyethylene is used to bond a layer of thermoplastic nylon or a nylon blend with a layer of a thermoplastic polyester or polyolefin. Because of the sheet having excellent adhesion, both between layers and to other substrates, it is especially useful as a carrier for decorative and protective coatings to be applied to substrates such as automobile panels.

Background of the Invention

As used herein, the term "sheet(s)" or "sheet material" includes thin film material as well as heavier sheets. Patents of interest include U.S. Patent

Nos. 4,643,926; 4,119,267; 4,210,686; 4,803,102; 4,939,009; 4,948,654; 4,910,085 and 4,349,469. The '926 patent discloses a flexible film comprising several layers of polymeric material. For example, one of the flexible films disclosed comprises a polyaHomer and a flexible copolyester tied together with various tie layers (for example, an ethylene propylene copolymer. Column 4, lines 7 and 8). Applicants' invention obtains unexpected improved results in adhesion using the low molecular weight polyethylene having a flow rate of 0.25 to 40 over the tie layers disclosed by this patent. Furthermore, published technical literature by Mitsui Petrochemical Industries, Ltd., directed to Admer resins discloses the utility of low molecular weight polyethylene resins as adhesive layers between various materials including certain plastics.

Description of the Invention According to one aspect of the present invention, there are provided multilayered films having excellent adhesion. The films are normally coextruded into three or five layered structures, i.e.. A—B—C or A—B—C—B-A, wherein A is a thermoplastic polyamide or polyamide blend, B is a modified low molecular weight polyethylene resin as defined herein, and C is a polyester or polyolefin.

According to the present invention, there is provided sheet material adapted for in—mold injection molding applications comprising a first outer layer, an intermediate tie layer and a second outer layer, a) the first outer layer comprising a crystalline or amorphous thermoplastic polyamide, b) the tie layer comprising a copolymer of ethylene or propylene and at least one other unsaturated monomer, the copolymer having a density of 0.85—1.00 g/cc, and c) the second outer layer comprising a polyolefin or polyester, the polyolefin being selected from polyethylene, polypropylene and ethylena/ ropylene copolymers having a melt flow rate of 4 to 20, and the polyester being selected from polymers and copolymers of polyethylene terephthalate, polycyclohexylene— dimethylene terephthalate, polybutylene terephthalate, and blends and copolymers thereof. The sheets as described above are particularly useful for in—mold applications when polyolefins are used as a molding material and the second outer layer is also polyolefin; and when polyesters or nylons are used as a molding material and the second outer layer is polyester.

Typical polyamides include polycaprolactam (Nylon 6) , poly—ω-aminoheptanoic acid (Nylon 7) , poly—o-j—aminonomanoic acid (Nylon 9) , polyundecanamide (Nylon 11) , polylauryllactam (Nylon 12) , polyethylene adipamide (Nylon 2—6) , polytetramethylene adipamide (Nylon 4-6) , poly—hexamethylene adipamide (Nylon 6-6) , polyhexamethylene sebacamide (Nylon 6—10) , polyoctamethylene adipamide (Nylon 8—6) , polydecamethylene adipamide (Nylon 10—6) and polydodecamethylene sebacamide (Nylon 12-10) .

Polyamides prepared from aromatic amino compounds are disclosed in U.S. Patent No. 3,408,334. The aromatic amines used in these polyamides contain amino groups bonded directly to an aromatic ring. Typical examples of suitable diamines are metaphenylenediamine, para—phenylenediamine, isomeric diaminoxylenes, etc. The patent further discloses that p— henylene— dioxydiacetic acid and similar compounds can be employed in the preparation of polyamides.

U.S. Patent No. 4,482,695 discloses polyamides prepared from an aliphatic diamine and a dicarboxylic acid which is a diacetic acid.

The polyamide or polyamide blend which is employed in the present invention exhibits an inherent viscosity of 0.4 to 1.5. The inherent viscosity is measured at 25°C in a 60/40 by weight mixture of phenol./ tetrachloroethane at a concentration of 0.5 g/100 ml.

Polymers having an inherent viscosity within this range are of sufficiently high molecular weight to be used in the present invention.

The polyamides used in the present invention are synthesized by methods generally known in the art for 4 -

producing polyamides. The diamine and diacid components are preferably reacted in approximately stoichiometic quantities. Diacid chlorides, esters, and the like can be used. A solvent may be used in the preparation of 5 the polyamide.

In general, the reaction involves heating approximately stoichiometric quantities of the diamine and diacid components in the presence of a small amount of water and in an inert atmosphere, such as nitrogen, 10 with stirring. A slight excess of the diamine may be desirable. Water is allowed to distill as the temperature is raised so as to facilitate reaction between the diamine and the dicarboxylic acid. Temperatures in the range of about 180° to 330°C may be 15 employed, with the preferred range being about 200° to

310°C. Preferably, the final stages of the reaction are conducted under a vacuum. The polymerization reaction is typically conducted for a period of time of about 2 to 30 hours. The preparation of the polyamide does not 20 require the use of a catalyst, and catalysts typically are not employed during the reaction period. However, suitable catalysts which have been disclosed in the literature can be employed if desired.

Blends of the nylon described above may also be 25 used for the outer layer A. Typical polymers which may be blended with the nylon are polyesters and styrenic copolymers. The term "nylon" as used herein is intended to include blends of nylon with up to about 50 weight % of such polymers. 30 The term "polyester" as used herein is intended to include copolyesters. Conventional polyesters, made using well—known conventional techniques, may be used for the layer C. Although poly(ethylene terephthalate) , poly(cyclohexanedimethylene terephthalate) , 35 poly(butylene terephthalate) and blends and copolymers thereof are preferred, the polyester may be made having repeat units from the glycols and dicarboxylic acids identified below.

The glycol component of the polyester may include aliphatic or alicyclic glycols. Examples of these glycols include ethylene glycol; propylene glycol;

1,3—propanediol; 2,4-dimethyl—2—ethylhexane—1,3-diol;

2,2—dimethyl-11,3-propanediol; 2—ethyl—2—butyl—

1,3-propanediol; 2—ethyl-2—isobutyl-1,3-propanediol; 1,3—butanediol, 1,4—butanediol; neopentyl glycol;

1,5—pentanediol; 1,6—hexanediol; 1,8—octanedol;

2,2,4-trimethyl-l,6—hexanediol; thiodiethanol;

1,2—cyclohexanedimethanol; 1,3—cyclohexanedimethanol;

1,4—cyclohexanedimethanol; 2,2,4,4—tetramethyl— 1,3—cyclobutanediol p—xylylenediol; and trimethylolpropane. Copolymers may be prepared from two or more of the above glycols.

The dicarboxylic acid component of the polyester comprises aliphatic dicarboxylic acid, alicyclic dicarboxylic acids, aromatic dicarboxylic acids, or mixtures of two or more of these acids. Examples of such dicarboxylic acids include succinic; glutaric; adipic; azelaic; sebacic; fumaric; aleic; itaconic;

1,4—cyclohexanedicarboxylic; phthalic; terephthalic, isophthalic, and naphthalene dicarboxylic acid. It should be understood that use of the corresponding acid anhydrides, esters, and acid chlorides of these acids is included in the term "dicarboxylic acid".

The outer layer C may be a polyester as described above, or it may be a polyolefin. Polymers or copolymers of a—olefins having 2 to 6 carbon atoms may be used. Preferred are polyethylene or polypropylene. Suitable polyolefins are commercially available, and include such materials as Tenite (trademark) polypropylene—4240 (melt flow rate of 9.0 g./10 min) and Tenite (trademark) polyallomer—5L2S (melt flow rate of 6.0 g/10 min) , both available from Eastman Chemical Products, Inc. and Shell polypropylene WRS7—327 (melt flow rate of 8 g/10 min) . Polyolefins used have a melt flow rate of 4—20, preferably 5—12.

The tie layer used in this invention is described as a low molecular weight copolymer of ethylene or propylene having as melt flow rate of 0.25 to 40.0 g/10 min., a tensile strength at break of at least 25 kg/cm , an elongation at break of greater than 50%, a melting point of at least 65°C and a density of 0.85—1.00 g/cc) .

The tie layer material of this invention is further described as having 0.1 to 30 weight percent of at least one unsaturated monomer copolymerized with ethylene, e.g., maleic acid, fumaric acid, acrylic acid, methacrylic acid, vinyl acetate, acrylonitrile, methacrylonitrile, butadiene, carbon monoxide, etc. Preferred are acrylic esters, maleic anhydride, vinyl acetate, and methacrylic acid. Many such polymers are commercially available under trademarks such as Admer AT-469C, Lotader AX-8040, Elvax 260, Dupont CXA3036 and 3101 and Lotader HX-8020.

Typically, the thicknesses of the layers are about 4—20 mils for the polyurethane elastomer, 0.5—3.0 mils for the tie layer and 4—20 mils for the amorphous copolyester.

The films according to the present invention are preferably formed by cast coextrusion using conventional techniques. The sheet material of this invention preferably includes a protective and decorative layer such as a paint layer on one of the outer layers.

The preferred manner of using the sheet material of this invention comprises the steps of providing a mold in the configuration of the shaped article; positioning within the mold the above described multilayered sheet material, injecting into the mold a fluid composition which is capable of hardening to both form the desired shaped article and bond to the sheet material; and removing from the mold a shaped article having a protective and decorative coating formed from the sheet material securely bonded thereto. In this instance, the sheet material is placed in a mold cavity, and a molding material is injected into the mold cavity under pressure against the sheet material such that the sheet material conforms to the shape of the molded article and bonds to the outer surface of the article. When the molding material is to be polyolefin, then the layer C should be polyolefin; when the molding material is to be nylon or polyester, then the layer C should be polyester.

Suitable molds, molding compositions and molding process parameters for this method are well known and form no part of the present invention. If desired, the sheet material may be preshaped prior to being placed in the mold. Also, conventional thermoforming techniques may be used.

The film layer materials may also contain stabilizers, colorants, processing aids, glass fibers, and flame retardants. This in—mold application of film laminates would preferably be applied to injection— olded parts which could be used in a number of applications. .An example would be automobile or truck parts such as bumpers, fascia, and trim applications (flexible or rigid) such as claddings, trim strips. These applications would be useful for parts experiencing high wear forces or loadings such as parts for materials handling equipment, recreational equipment or vehicles. The film laminate could also be used with reaction injection molding processes and with vacuum forming processes.

The following examples are submitted for a better understanding of the invention.

Also, in the examples, the tie layers are described as follows:

Tie Layer from ADMER AT469C Polymer. A copolymer containing mostly repeat units from ethylene, having a melt flow rate (190°C) of 1.0 g/10 min, a density of

0.88 g/cm 3, a tensi.le strength at break of 30 kg/cm2, an elongation at break of >500 percent, Izod impact strength of unbreakable, a D-shore hardness of 16, an

A—shore hardness of 72, a melting point of 75°C and excellent clarity.

Tie layer from Bynel CXA E—318./E—319 — Ethylene

Copolymer having following properties: -3 8 E-319

Tie Layer from Bynel CXA E—306 — Propylene Copolymer having following properties:

Melt Flow Rate at 230°C 6.8

Density .903 g/cc Freezing Point 100°C

Melting Point 136°C

Vicat Softening Point 115°C Tie Layer from Bynel CXA 3101 — Ethylene Polymer having following properties:

Melt Index at 190°C 3.5 dg/min Density .943 g/cc

Melting Point 87°C

Freezing Point 69°C

Vicat Softening Point 65°C

Tensile Strength 13.26 mPa (1,920 psi) Tensile Modulus 32.99 mPa (4,780 psi)

Elongation at Break 640%

Tie Layer from Kraton G Polymer - hydrogenated styrene—butadiene—isoprene block copolymers having functionality such as maleic groups.

Tie Layer from Bynel CXA E—357/E—359 — Ethylene Vinyl Acetate Copolymer having following properties:

In the above tie layer composition, the following tests are used:

Melt Index and Flow ASTM D-1238 Rate

Density ASTM D-1505

Melting and Freezing Differential Scanning Points Calorimetry

Vicat Softening Point ASTM D-1525

Tensile Strength ASTM D-1708

Elongation at Break ASTM D-1708

Example 1

A three—layer film laminate is coextruded from Allied Chemical Capron 8200 HS nylon 6 for the outside layer (layer A) , Mitsui ADMER AT469C modified polyolefin for the tie layer (layer B) , and Shell polypropylene WRS7—327 for the layer C. The melt temperatures are 255, 268, and 268°C for layers A, B and C, respectively. Coextrusion block temperatures are set at 263°C. Film thicknesses are 5.0, 2.0, and 3 mils, for layers A, B and C, respectively. Coextruded film is placed in the mold of an injection molding machine. Thermoplastic polyolefin (TPO) is injection molded onto the film with a melt temperature of 442°F (228°C) and mold temperature of 98-104°F (37-40^βC). This TPO contains Shell WRS7-328 polypropylene. Thickness of the TPO substrate for this process is about .10 in.

Peel strength of the three layer film laminate is measured using a 180 degree peel test (ASTM D903) at a peel rate of 2 in./min (5.08 cm in) . After the TPO is injection molded onto the film, the average peel strength is measured to be 10.9 lb/in. (194 g/mm) , and maximum peel strength was 11.6 lb/in. (207 g/mm). Example 2

The same film components for layers A and C as for Example 1 are used. The tie layer B is Dupont Bynel E306. The melt temperatures are 265, 250, and 240°C for layers A, B and C, respectively. Coextrusion block temperature is 265°C. Film thicknesses are 4.5, 2, and 4 mils for layers A, B and C, respectively. Injection molding conditions are the same as those used in Example 1. After injection molding of the TPO onto the film, average peel strength for the coextruded film is 10.8 lb/in. (193 g/mm) and peak strength is 11.1 lb/in. (198 g/ϊam) .

Example 3 A three—layer film laminate is coextruded from GE Noryl N-300 polyphenylene oxide/nylon blend for outside layer A, Mitsui .ADMER AT469C modified polyethylene for the tie layer (layer B) , and Shell polypropylene WRS7—327 for layer C. The melt temperatures are 275, 260, and 239°C for layers A, B and C, respectively. Coextrusion block temperature is set at 310°C. Film thicknesses are 5.0, 2.0, and 3 mils, for layers A, B and C, respectively. Peak peel strength is measured to be 4.1 lb/in. (73 g/mm) and the average peel strength is 3.1 lb/in. (55 g/mm). Thermoplastic polyolefin described in Example 1 is injection molded onto the film with a melt temperature of 442°F (228°C) and mold temperature of 98—104^βF (37—40^βC) . After molding the peak peel strength is 3.7 lb/in. (66 g/mm) and the average peel strength is 3.1 lb/in. (55 g/mm) .

Example 4

A three—layer film laminate is coextruded with the same layer A and C materials as in Example 3. The tie layer B is changed to Shell Kraton G—1901X elastomer. Extrusion temperatures and layer thicknesses are the same as for Example 3. Thermoplastic polyolefin as described in Example 1 is injection molded onto the film with a melt temperature of 442°F (228°C) and mold temperature of 98—104°F (37-40°C) . After molding, the peak peel strength is measured to be 13.9 lb/in. (248 g/mm) and the average peel strength 11.2 lb/in. (200 g/mm) .

Example 5

A three—layer film laminate is coextruded from Monsanto Triax 1120 nylon/acrylonitrile—butadiene— styrene blend for outside layer A, Mitsui ADMER AT469C modified polyethylene for the tie layer B, and Shell polypropylene WRS7—327 for the inside layer C. The melt temperatures are 274, 254, and 225°C for layers A, B and C, respectively. Coextrusion block temperature is set at 270°C. Film thicknesses are 5.0, 2.5, and 3 mils, for layers A, B and C, respectively. Peak peel strength for the coextruded film before injection molding is 2.7 lb/in. (48 g/mm) and average peel strength is 2.1 lb/in. (38 g*mm) . Thermoplastic polyolefin as described in Example 1 is injection molded onto the film with a melt temperature of 442°F (228°C) and mold temperature of 98—104°F (37—40°C). After molding the peak peel strength is 4.3 lb/in. (77 g/mm) and the average peel strength is 3.2 lb/in. (57 g/mm).

Example 6 A three—layer film laminate is coextruded with the same materials as in Example 5 except that the tie layer is Dupont Bynel E359. Extrusion temperatures and film thicknesses are the same as for Example 5. Peak peel strength is .9 lb/in. (16 g/mm) and average peel strength is .6 lb/in. (11 g/mm) for the film laminate before injection molding. Thermoplastic polyolefin as described in Example 1 is injection molded onto the film with a melt temperature of 442°F (228°C) and mold temperature of 98—104°F (37—40°C) . This TPO contains Shell WRS7-328 polypropylene. Thickness of the TPO substrate for this process is about .10 in. After molding the peak peel strength is 2.8 lb/in. (50 g/mm) and the average peel strength is 2.4 lb/in. (43 g/mm).

Example 7

A three—layer film laminate is coextruded from the copolyester poly(cyclohexylenedimethylene terephthalate) for the outside layer C, Mitsui ADMER AT469C modified polyethylene for the tie layer B, and Allied Chemical Capron 8200 HS nylon 6 for the layer A. The melt temperatures are 289, 271, and 260°C for layers C, B and A, respectively. Coextrusion block temperature are set at 298°C. Film thicknesses are 5.0, 2.0, and 3 mils, for layers C, B and A, respectively. Nylon 6 (same material as for layer A of the film laminate) is injection molded onto the film with a melt temperature of 450°F (232°C) and mold temperature of 98-104°F (37—40^βC) . Thickness of the nylon substrate for this process is about .10 in. Peel strength of the three layer film laminate is measured using a 180 degree peel test (ASTM D903) at a peel rate of 2 in./min (5.08 cmmin) . The average peel strength is measured to be 7.3 lb/in. (130 g/mm) and peak peel strength to be 7.5 lb/in. (134 g/aim) . After the nylon is injection molded onto the film, the average peel strength is measured to be 8.2 lb/in. (147 g/mm) and peek peel strength to be 10.3 lb/in. (184 g mm). Example 8

Processing conditions are identical to those for Example 7 except that the tie layer material is DuPont Bynel CXA 3101. Average peel strength of the film laminate is 5.8 lb/in. (104 g/mm) and peak peel strength is 10.6 lb/in. (189 g/mm). After molding the average peel strength is 8.6 lb/in. (154 g/mm) and the peak peel strength is 10.8 lb/in. (193 g/mm).

Example 9

A three—layer film laminate is coextruded from copolyester polycarbonate blend for the outside layer C, Shell Kraton G—2720X for the tie layer B, and Allied Chemical Capron 8200 HS nylon 6 for the layer A. The copolyester contains repeat units from terephthalic acid about 75—85 ol % 1,4—cyclohexanedimethanol and about 25—15 mol % ethylene glycol. The melt temperatures are 268, 260, and 262°C for layers C, B and A, respectively. Coextrusion block temperature is set at 278°C. Film thicknesses are 4.0, 2.0, and 3.5 mils, for layers C, B and A, respectively. Average peel strength for the film laminate is measured to be 4.2 lb/in. (75 g/mm) and the peak peel strength is 4.4 lb/in. (79 g/mm) . Nylon 6 similar to the layer A material is injection molded onto the film with a melt temperature of 450°F (232°C) and mold temperature of 98—104°F (37—40°C) . After molding the average peel strength is 3.8 lb/in. (66 g/mm) and peak peel strength is 5.2 lb/in. (93 g.mm) .

Example 10

A three—layer film laminate is coextruded from Allied Chemical Capron 8200 HS nylon 6 the outside layer A, DuPont Bynel CXA 3101 for the tie layer B, and polyethylene terephthalate (PET) for the layer C. The melt temperatures are 272, 250, and 244°C for layers A, B and C, respectively. Coextrusion block temperature is set at 275°C. Film thicknesses are 5.0, 2.5, and 3 mils, for layers A—C. Average peel strength for the coextruded film before injection molding is 3.2 lb/in. (57 g/mm) and peak peel strength is 4.5 lb/in.

(80 g/mm) . Glass—fiber reinforced PET is injection molded onto the film with a melt temperature of 520°F (27l°C) and mold temperature of 98-l04°F (37-40°C) . A smooth film-molded sample laminate is formed with average peel strength of 3.2 lb/in. (57 g/mm) and the peak peel strength of 3.8 lb/in. (68 g/mm).

Example 11

A three—layer film laminate is coextruded from Allied Chemical Capron 8200 HS nylon 6 the outside layer A, DuPont Bynel CXA E319 for the tie layer (layer B) , and polyethylene terephthalate for layer C. Processing conditions are the same as for Example 10. Average peel strength for the coextruded film before injection molding is 2.5 lb/in. (45 g/mm) and peak peel strength is 4.8 lb/in. (86 g/mm). Glass—fiber reinforced PET is injection molded onto the film with a melt temperature of 520°F (271°C) and mold temperature of 98-104°F (37-40°C). A smooth film-molded sample laminate is formed with average peel strength of

2.9 lb/in. (52 g,mm) and the peak peel strength of

In the above examples, from the peel strengths it can readily be seen that there is excellent adhesion between this sheet and the substrate. Also, using the protective and decorative sheet according to this invention provides a high quality coating of attractive appearance. There appear to be no detrimental effects on the finish resulting from the molding procedure. Whenever the term "inherent viscosity" (I.V.) is used in this application, it will be understood to refer to viscosity determinations made at 25°C using 0.50 gram of polymer per 100 mL of a solvent composed of 60 wt % phenol and 40 wt % tetrachloroethane.

The "melting point" (T ) of the polymers described in this application are readily obtained with a Differential Scanning Calorimeter.

The strength of the bonds is determined by the "Peel Test" based on a modification (i.e., three test specimens) of the ASTM "T—Peel Test" set forth on pages 63 and 64 of the 1964 edition of the BOOK OF ASTM STANDARDS, published by the American Society of Testing Materials, and more specifically identified as Test Number D-1876-61-T.

Unless otherwise specified, all parts, percentages, ratios, etc., are by weight.

The invention has been described in detail with particular reference to preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention.

Claims

1. Sheet material adapted for in—mold injection molding applications characterized as having a first outer layer, an intermediate tie layer and a second outer layer, a) said first outer layer comprising a thermoplastic polyamide, b) said tie layer comprising a copolymer of ethylene or propylene and at least one other unsaturated monomer, said copolymer having a density of 0.85—1.00 g/cc, and c) said second outer layer comprising a polyolefin or polyester, said polyolefin selected from polyethylene, polypropylene and ethylene/propylene copolymers having a melt flow rate of 4 to 20, and said polyester being selected from polymers and copolymers of polyethylene terephthalate, polycyclohexylene- dimethylene terephthalate, and polybutylene terephthalate.

2. Sheet material according to Claim 1 wherein said polyamide is nylon 6 or nylon 6,6.

3. Sheet material according to Claim 1 wherein said polyamide is blended with a polyester, polyphenylene oxide or a styrenic polymer.

4. Sheet material according to Claim 1 wherein said ethylene copolymer is a copolymer of ethylene with a monomer selected from maleic acid, fumaric acid, acrylic acid, methacrylic acid, vinyl acetate, acrylonitrile, ethacryonitrile, butadiene and carbon monoxide.

5. Sheet material according to Claim 1 wherein said ethylene or propylene copolymer has a melt flow rate of 0.25—40 g/10 min, a tensile strength at break of at least 25 g/cm , an elongation at break of greater than 50% and a melting point of at least 65°.

6. Sheet material according to Claim 5 wherein said ethylene or propylene copolymer has a melt flow rate of 0.5—20 g/10 min, and an elongation at break of greater than 400%.

7. Sheet material according to Claim 1 wherein said ethylene or propylene copolymer has a melt flow rate of 0.8—1.2 g/10 min, a tensile strength at break of 20-40 kg/cm², an elongation at break of greater than 50%, an Izod impact strength of unbreakable, a D-shore hardness of about 14—18, an A—shore hardness of 70—74 and a melting point of 70°-80°C.

8. Sheet material according to Claim 1 provided with a decorative or protective coating on said first outer layer.

9. A molded article having sheet material according to Claim 1 adhered to one side thereof.