Multilayer clear over color polyolefin sheets and layered backing structure
AssigneeA. Schulman, Inc.
InventorDennis C. Smith
Life of this patent
Estimating the term…
Abstract
A multilayer structure includes a clear polyolefin layer, a colored polyolefin layer, and a random polyolefin backing layer. The colored and backing layers are coextruded and are permanently bonded at a layer interface, which is exclusive of an adhesive. The structure has a DOI of 70 or greater and passes a gravelometer impact test per the GM9508P standard, with a 10 pint load, at a −30° C. temperature, and at an impact angle of 30 degrees. Among other uses, the structures are appropriate for use as body panels in the motor vehicle industry. The structures display a “class A” finish and meet a variety of requirements for durability and weatherability. An ABA structured backing layer and a method of making it are also described herein.
Claims39
A multilayer structure comprising:
- a clear polyolefin layer;
- a colored polyolefin layer;
- a polyolefin backing layer with a random microstructure;
- the colored and backing layers are coextruded and are permanently bonded at a layer interface;
- the interface is exclusive of an adhesive layer;
- the structure has a DOI of 70 or greater;
- and
- the structure passes a gravelometer impact test per the GM9508P standard, with a 10 pt load, at a −30° C. temperature, and at an angle of 30 degrees.
A formed product comprising:
- a coextruded clear isotactic polypropylene/ethylene copolymer layer of 2.5 mils to 20 mils in thickness;
- a coextruded colored isotactic polypropylene/ethylene copolymer layer of 3 mils to 20 mils thick;
- and
- a polyolefin backing layer with a random microstructure;
- the clear and color layers are coextruded and are permanently bonded at a layer interface;
- the formed product has a DOI of 70 or greater;
- the formed product is substantially non-oriented by stretching;
- the formed product has a gloss of 75 or greater at a 60° angle and a gloss of 60 or greater at a 20° angle;
- the clear polyolefin layer has a light transmittance of 90% or greater;
- the clear polyolefin layer has a haze of 10 or less;
- the formed product exhibits no gauze imprint at 70° C. minimum under a 500 g load applied over a 40 mm diameter for two hours;
- the formed product passes a gravelometer impact test per the GM9508 standard, with a 10 pint load, at a −30° C. temperature, and at an impact angle of 30 degrees.
A vehicle body panel including a multilayer structure, the multilayer structure comprising:
- a coextruded clear isotactic polypropylene/ethylene copolymer layer of 2.5 mils to 20 mils in thickness;
- a coextruded colored isotactic polypropylene/ethylene polyolefin layer of 3 mils to 20 mils thick;
- and
- a polyolefin backing layer with a random microstructure;
- the clear and color layers are coextruded and are permanently bonded at a layer interface;
- the structure has a DOI of 70 or greater;
- the structure is substantially non-oriented by stretching;
- the structure has a gloss of 75 or greater at a 60° angle and a gloss of 60 or greater at a 20° angle;
- the clear polyolefin layer has a light transmittance of 90% or greater;
- the clear polyolefin layer has a haze of 10 or less;
- the structure exhibits no gauze imprint at 70° C. minimum under a 500 g load applied over a 40 mm diameter for two hours;
- the structure passes a gravelometer impact test per the GM9508 standard, with a 10 pint load, at a −30° C. temperature, and at an impact angle of 30 degrees;
- and
- the clear and/or color layers include an additive selected from the group consisting of:
- antioxidants, UV stabilizers, slip agents, and combinations of these.
A multilayer structure comprising:
- a polyolefin layer;
- a colored polyolefin backing layer with a random microstructure;
- the polyolefin and backing layers are coextruded and are permanently bonded at a layer interface;
- the interface is exclusive of an adhesive layer;
- the structure has a DOI of 70 or greater;
- and
- the structure passes a gravelometer impact test per the GM9508P standard, with a 10 pt load, at a −30° C. temperature, and at an angle of 30 degrees.
Dependencies are inferred from the claim text.