(a) Technical Field
The present invention relates to a thermoelastic polyolefin-based elastomer sheet composition for water based coating treatment. More particularly, it relates to a thermoelastic polyolefin-based elastomer sheet composition for water based coating treatment that exhibits improved elongation, heat resistance, light resistance, humidity resistance and molding property so as to be used for coating or surface treating vehicular inner parts, e.g., crash pad.
(b) Background Art
Alloy extrusion sheet or calendering sheet prepared using vinyl chloride or vinyl chloride/acrylonitrile butadiene styrene elastomer was used as a surface material of various inner parts of a vehicle, including, e.g., instrument panel, door trim panel and headlining. Such sheets have been replaced with thermoelastic polyolefin-based elastomer sheet, which is eco-friendly, light, and resistant to fogging and odors.
Vehicular inner parts can be coated or surface treated for improving physical properties (e.g., friction resistance and abrasion resistance), chemical properties (e.g., resistance to chemicals and solvents) and light resistance. Such coating or surface treatment also can lower gloss to secure the vision of a driver and make the surface color in harmony with surrounding parts.
Thermoelastic polyolefin-based elastomer sheet has a non-polar and high crystalline structure, and its adhesion property is poor. Thus, it requires surface treatment using, for example, flame, ozone, plasma, or chlorinated polyolefin resin-based primer, followed by treatment with acrylated resin-based base coating material and urethane resin-based clear coating material.
Many attempts have been made to provide a composition comprising thermoelastic polyolefin-based elastomer. Korean patent No. 10-0506754, for example, discloses a composition comprising a highly crosslinked polypropylene resin, a partially crosslinked polypropylene-based resin, a reactive propylene-based resin, a highly crosslinked thermoelastic olefin resin, a homopropylene resin, a branched polypropylene resin, a linear low density polyethylene resin, a UV stabilizer, a lubricant and a pigment.
Also, Korean patent No. 10-0547657 discloses a composition comprising a polyolefin-based thermoelastic resin, an ethylene-propylene-diene rubber, an ethylene-octene copolymer and a resin crosslinker.
These compositions, however, have disadvantages. They show low adhesion with aqueous coating material. They also have low elongation.
Therefore, there exists a need for developing an elastomer sheet composition that can overcome the above-described problems associated with prior art.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.