Surface protection film
View Patent ↗An illustrative aspect of the invention provides a film comprising a release layer defining a first outer film surface and an adhesion layer defining a second outer film surface opposite the first outer film surface. The adhesion layer comprises a hydrogenated styrene block copolymer with a styrene content in a range of about 30% to 40% by weight. In some embodiments, the adhesion layer may further comprise low density polyethylene (LDPE). In some embodiments, the adhesion layer may further comprise LDPE and high density polyethylene (HDPE).
1. A film comprising:
a release layer defining a first outer film surface; and
an adhesion layer defining a second outer film surface opposite the first outer film surface, the adhesion layer comprising a hydrogenated styrene block copolymer with a styrene content in a range of about 30% to about 40% by weight,
wherein the hydrogenated styrene block copolymer is in a range of 15% to 80% by weight of the adhesion layer and the adhesion layer further comprises 10% to 50% by weight of low density polyethylene and 10% to 35% by weight of high density polyethylene.
2. The film of claim 1 , wherein the hydrogenated styrene block copolymer is in a range of 25% to 50% by weight of the adhesion layer and the adhesion layer further comprises 25% to 40% by weight of low density polyethylene and 25% to 35% by weight of high density polyethylene.
3. The film of claim 1 , wherein the hydrogenated styrene block copolymer is about 33% by weight of the adhesion layer and the adhesion layer further comprises about 32% by weight of low density polyethylene and about 35% by weight of high density polyethylene.
4. The film of claim 1 wherein the release layer comprises at least one of the set consisting of low density polyethylene, linear low density polyethylene, high density polyethylene, medium density polyethylene, polypropylene, random copolymer polypropylene, polypropylene impact copolymers, metallocene linear low density polyethylene.
5. The film of claim 1 wherein the release layer comprises low density polyethylene and high density polyethylene.
6. The film of claim 5 wherein the release layer comprises 40-60% by weight of low density polyethylene and 40-60% by weight of high density polyethylene.
7. The film of claim 1 , wherein the film exhibits a 180 degree peel strength of less than 100 grams per inch at 23 degrees C. after application to a smooth polycarbonate surface.
8. The film of claim 1 , wherein the film exhibits a 180 degree peel strength of less than 25 grams per inch at 23 degrees C. after application to a smooth polycarbonate surface.
9. The film of claim 1 , wherein the film exhibits a 180 degree peel strength of less than 200 grams per inch at 60 degrees C. after application to a smooth polycarbonate surface.
10. The film of claim 1 , wherein the film exhibits a 180 degree peel strength of less than 50 grams per inch at 60 degrees C. after application to a smooth polycarbonate surface.
11. The film of claim 1 , wherein the film exhibits a 180 degree peel strength of less than 140 grams per inch at 90 degrees C. after application to a smooth polycarbonate surface.
12. The film of claim 1 , wherein the film exhibits a 180 degree peel strength of less than 60 grams per inch at 90 degrees C. after application to a smooth polycarbonate surface.
13. The film of claim 1 , wherein the film exhibits a 180 degree peel strength of at least 5 grams per inch but less than 50 grams per inch at 60 degrees C. after application to a smooth polycarbonate surface.
14. The film of claim 1 , wherein the film exhibits a 180 degree peel strength of at least 20 grams per inch but less than 60 grams per inch at 90 degrees C. after application to a smooth polycarbonate surface.
15. The film of claim 1 , wherein the film exhibits a 180 degree peel strength less than 40 grams per inch between the first outer film surface of a first portion of the film and the second outer film surface of a second portion of the film after the second portion has been pressed against the first portion for 1 hour under a pressure of 2000 psi.
16. The film of claim 1 , wherein the film exhibits a 180 degree peel strength less than 10 grams per inch between the first outer film surface of a first portion of the film and the second outer film surface of a second portion of the film after the second portion has been pressed against the first portion for 1 hour under a pressure of 2000 psi.
17. The film of claim 1 further comprising a core layer intermediate the adhesion layer and the release layer.
18. The film of claim 17 wherein the core layer consists essentially of one of the set consisting of low density polyethylene, high density polyethylene, and a blend of low density polyethylene and high density polyethylene.