CA1188970A

CA1188970A - Multi layer laminated molding

Info

Publication number: CA1188970A
Application number: CA000409511A
Authority: CA
Inventors: Christopher Hatzikelis; Ciro Madonia; Cesare C. Cosentino
Original assignee: Individual
Current assignee: Individual
Priority date: 1982-08-16
Filing date: 1982-08-16
Publication date: 1985-06-18

Abstract

ABSTRACT.
An extruded multi layer laminated molding incorporates an intermediate polyolefin layer, generally in the form of a film or tape having the property of providing non-delaminating adherence to adjoining layers comprising a polyvinyl chloride section on the one side and a thermoplastic rubber section on the other side. The two sections are normally incompatible, and use of the intermediate layer permits the use of thermo-plastic rubber in combination with the versatility and ex-trusion fabrication techniques developed for polyvinyl chloride.

Description

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This invention is direc-ted to elongated decorative and protective lamina-te moldîngs, including trim as used in the automotive industry.
Elongated moldings are used for protecive and decorative purposes~ such as cove base trim in households and body molding trim in the automotive industry, to name bu-t two such applications.
Trim is generally derived from petro-chemical stock primarily in the form of polyvinyl chloride (PVC)~ Another family of material, thermoplastic rubbers (TPRis) provide a number of significant practical advantages over PVC, owing to the absence of platlcizers in the TPR's and their dimensional stability, characterized by substantial non-shrinkage together with lower density and smooth "running" characteristics which facilitate ready extrusion. ~Iowever9 TPR~s do not laminate with PVC, nor do TPR's bond to polyethylene -terapthalate (MYLARtm) so that to-date it has no-t been possible to utilize existing developed PVC -techniques for the fabricatlon and decora-tion of trim incorpora-ting TPR's.
I-t has been found -that the non-laminatlng relation-shlp between TPR's and PVC can be overcome, using a sui-table solid polyolefin la~er in-terposed between the TPR and PVC :in bondin~, isolating relation with the two other materials.
Thus, -the provision of ~the adhesion system herein set for~th permits the ready bonding of normally incompa-tible materials in an e~truslon system utilizing the superior flow aspects of TPR'sg generally by simultaneous e~-trusion and bonding to the intermediate layer~ as coated on a PVC -tape~
The present invention thus pxovides a composite trim sec-tion having a firs-t e~truded section portion of ." ~
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thermoplastic rubber, a second section portion substantially longitudinally coextensive therewith, being of polyvinyl chloride not generally adherable wi-th the first por-tion, the first and second portions each having a surface area in facing relation with the other portion, and an intermediate portion located in isolating rela-tion between the first and second portions and constituting a single componen-t non-liquid polyolefin adheren~y compatibl.e with the material of the first and second portions, to provide substantially non-delaminating adhesion between the portions~
The subject trim comprises an elongate structure of substantially uniform cross section sandwich construc-tion consis-ting essentially of a bonded ~tri-lamina~te structure having two adhesively incompatible layers, one layer com-prising thermoplastic rubber and the other a polyvinyl chloride having an intermediate layer comprising a single componen~t polyolefin plastic being in itself mutually ad-hesively compatible with the other layers and cons-ti-tu-ting the sole fàstening agen-t securing the o-ther layers in secured, substan-tially non-delaminating rela-tion.
A poleolefin such as polypropylene of a wea-therable -type resis~tanct~ to ultra violet degredation is well suited .~or -the subject use, Certain embodiments of -the invention are described wherein:
~igure 1 is a schematic cross-section of a possible composite section according to the present invention having the elements therof in exploded relation;
~igure 2 is a preferred embodiment showing a more typical form, and ~igure 3 i5 an alternatLve section that is contem-plated.
The schematic section 12 of Figure 1 has a base section 14 of TPR, an intermediate layer 16 of polyoleifn and an upper layer 18 of PVC.
In the Figure 2 embodiment, which more closely resembles a typical molding, the sectlon 22 comprises a shaped, extruded base secti.on 24 of TPR, an lntermediate layer 26 of polypropylene adhering thereto, having an upper layer 28 of PVC adhering to the layer 26.
In the Figure 3 embodiment it is con-templated that the particular characteristics of the materials facilitates -the provision o~ a hollow composite section 32 having a base section 34 of TPR~ intermediate edge layers 36 ofpoly-propylene, and an upper layer 38 of PVC. ~s before stated, the polypropylene will for most usages be of the wea-therable type, capable of withstanding ultra-violet degradation by sunlight.
The form of trim shown in ~igure 2 is then suited for completion by the addition of mylar and other decorative finishes to -the PVC, by established procedures, including the provision of additional protective fini.shes. In this regard, the relative shapes of -the sections are not limited t,o -the embodiments illus-trated.
In the ~igure 2 embodimen-t~ the portions 28 may comprises a PVC tape having a thickness such as 5 mil (0~005 inches), the polypropylene layer 2~ possible being a desposition of abou-t 1 mil, to provide the desired adh.esion, by pressurized thermal bondi.ng to -the base 24.
While polypropylene is specifically disclosed as having the desired bonding characteristic -to both PVC and to TPR, it is anticipated that o-ther polyolefins also possess sati.sfactory bondi.ng characteristics to both classes of substance to pro~ide utility.

Claims

WHAT I CLAIM BY CANADIAN LETTERS PATENT IS:

1. A composite trim section having a first extruded portion of a thermoplastic rubber, a second portion sub-stantially longitudinally co-extensive therewith being of polyvinyl chloride film not generally adherable with said first portion, said first and second portions each having a surface area in facing relation with the other portion, an intermediate portion located between said facing area portions of a third material bonded in heat sealed relation to said thermplastic rubber constituting the sole securing agent between said first and second portions consisting of a single component poly-olefin being in itself adherently compatible with said first and second portions, to provide substantially non-delaminating adhesion between said portions, said polyvinyl chloride film having a decorative finish layer in adherent protective relation therewith.

2. The trim section of Claim 1, said decorative finish layer being of polyethylene teraphthalate.

3. The trim section of Claim 1, wherein said polyolefin is polypropylene.

4. The trim section of Claim 1, wherein said polyvinyl chloride film is a tape having said polyolefin secured in adhering relation to one face thereof.

5. The trim section of Claim 4, wherein said polyolefin is bonded to said extruded portion of thermoplastic rubber simultaneously with the extrusion thereof.