Conformable retroreflective film structure
View Patent ↗The present invention includes conformable retroreflective structures. In some embodiments, the conformable retroreflective structures are also shrink resistant. The conformable retroreflective structures include a transparent plasticized polyvinyl chloride film having a first side and a second side; a first transparent polymer layer overlying the first side of the plasticized polyvinyl chloride film; a second transparent polymer layer overlying the second side of the plasticized polyvinyl chloride film; an array of retroreflective cube-corner elements underlying the second transparent polymer layer; and a plasticizer resistant adhesive underlying the array of retroreflective cube-corner elements. In some embodiments, the first and second transparent polymer layers are transparent, radiation-cured polymer layers.
1. A conformable retroreflective structure, comprising:
a) a transparent plasticized polyvinyl chloride film having a first side and a second side;
b) a first transparent polymer layer overlying the first side of the plasticized polyvinyl chloride film;
c) a second transparent polymer layer overlying the second side of the plasticized polyvinyl chloride film;
d) an array of retroreflective cube-corner elements underlying the second transparent polymer layer; and
e) a plasticizer-resistant adhesive underlying the array of retroreflective cube-corner elements.
2. The retroreflective structure of claim 1 wherein the transparent plasticized polyvinyl chloride film has a thickness of about 0.004 to about 0.1 inches (about 0.01 to about 2.5 mm).
3. The retroreflective structure of claim 1 wherein the transparent plasticized polyvinyl chloride film has a thickness of about 0.012 to about 0.018 inches (about 0.35 to about 0.46 mm).
4. The retroreflective structure of claim 1 wherein the transparent plasticized polyvinyl chloride film includes a fluorescent dye.
5. The retroreflective structure of claim 1 wherein the first transparent polymer layer has a thickness of about 0.0002 to about 0.001 inches (about 0.0051 to about 0.025 mm).
6. The retroreflective structure of claim 1 wherein the first transparent polymer layer has a thickness of about 0.0004 to about 0.0009 inches (about 0.01 to about 0.023 mm).
7. The retroreflective structure of claim 1 wherein the second transparent polymer layer has a thickness of about 0.0002 to about 0.001 inches (about 0.0051 to about 0.025 mm).
8. The retroreflective structure of claim 1 wherein the second transparent polymer layer has a thickness of about 0.0004 to about 0.0009 inches (about 0.01 to about 0.023 mm).
9. The retroreflective structure of claim 1 wherein the first and second transparent polymer layers include an aliphatic polyurethane acrylate.
10. The retroreflective structure of claim 1 wherein the first and second transparent polymer layers are formed from compositions which include aliphatic urethane acrylate prepolymer, monofunctional acrylate prepolymer, multifunctional acrylate prepolymer, and a photoinitiator or a blend of photoinitiators.
11. The retroreflective structure of claim 1 wherein the plasticizer-resistant adhesive is selected from the group consisting of silicone adhesives and acrylic adhesives.
12. The retroreflective structure of claim 1 wherein the plasticizer-resistant adhesive is a crosslinked, plasticizer-resistant acrylic adhesive.
13. The retroreflective structure of claim 1 wherein the plasticizer-resistant adhesive has a thickness of about 0.002 to about 0.005 inches (about 0.051 to about 0.13 mm).
14. The retroreflective structure of claim 1 wherein the plasticizer-resistant adhesive has a thickness of about 0.001 to about 0.003 inches (about 0.025 to about 0.076 mm).
15. The retroreflective structure of claim 1 wherein the array of retroreflective cube-corner elements is coated with a metallized reflective layer.
16. The retroreflective structure of claim 15 wherein the metallized reflective layer includes a metal selected from the group consisting of aluminum, silver, gold, and palladium.
17. The retroreflective structure of claim 15 wherein the plasticizer-resistant adhesive is bonded to the metallized reflective layer.
18. The retroreflective structure of claim 1 further including a polymeric film layer sealed through the array of retroreflective cube-corner elements and the second transparent polymer layer to the plasticized polyvinyl chloride layer.
19. The retroreflective structure of claim 18 wherein the plasticizer resistant adhesive is bonded to the polymeric film layer.
20. A conformable retroreflective structure, comprising:
a) a transparent plasticized polyvinyl chloride film having a first side and a second side;
b) a first transparent polymer layer overlying the first side of the plasticized polyvinyl chloride film, wherein the first transparent polymer layer has a thickness of about 0.0004 to about 0.0009 inches (about 0.01 to about 0.023 mm);
c) a second transparent polymer layer overlying the second side of the plasticized polyvinyl chloride film, wherein the second transparent polymer layer has a thickness of about 0.0004 to about 0.0009 inches (about 0.01 to about 0.023 mm);
d) an array of retroreflective cube-corner elements underlying the second transparent polymer layer; and
e) a plasticizer-resistant acrylic adhesive underlying the array of retroreflective cube-corner elements.
21. The conformable retroreflective structure of claim 20 wherein the first transparent polymer layer includes at least one polymer selected from the group consisting of polyurethane, polyether polyurethanes, polyester polyurethanes, and polycarbonate polyurethanes.
22. The conformable retroreflective structure of claim 20 wherein the first transparent polymer layer is a radiation-cured layer of polyurethane acrylate.
23. The conformable retroreflective structure of claim 20 wherein the second transparent polymer layer includes at least one polymer selected from the group consisting of polyurethane, polyether polyurethanes, polyester polyurethanes, and polycarbonate polyurethanes.
24. The conformable retroreflective structure of claim 20 wherein the second transparent polymer layer is a radiation-cured layer of polyurethane acrylate.
25. A method for manufacturing a conformable retroreflective structure, comprising:
a) attaching a first transparent polymer layer on a first side of a transparent plasticized polyvinyl chloride film;
b) attaching a second transparent polymer layer on a second side of the transparent plasticized polyvinyl chloride film;
c) positioning an array of retroreflective cube-corner elements to underlie the second transparent polymer layer; and
d) applying a plasticizer-resistant acrylic adhesive to underlie the array of retroreflective cube-corner elements.
26. The method of claim 25 further including depositing a metallized reflective layer on the array of retroreflective cube-corner elements.
27. The method of claim 26 wherein the plasticizer-resistant acrylic adhesive is applied to the metallized reflective layer.