Brightness enhancement film
A brightness enhancement film including a monolithic layer and a microstructured layer adjacent the monolithic layer. The microstructured layer has a first major surface and an opposing second major surface. The first major surface includes a first plurality of microstructures and the second major surface faces the first monolithic layer. The monolithic layer includes a polyester that includes at least about 70 mole percent naphthalenedicarboxylate groups based on total carboxylate groups. The polyester may include one or more catalysts having a total concentration by weight in a range of 10 to 1000 ppm. The first monolithic layer has a thickness in the range of about 5 μm to about 300 μm. The first monolithic layer may be substantially free of non-catalyst particulate matter and may have a haze of less than 1 percent.
1. A brightness enhancement film comprising:
a first monolithic layer;
a first microstructured layer adjacent the first monolithic layer, the first microstructured layer having a first major surface and an opposing second major surface, the first major surface comprising a first plurality of microstructures, and the second major surface facing the first monolithic layer;
a second monolithic layer immediately adjacent the first monolithic layer opposite the first microstructured layer; and
a third monolithic layer immediately adjacent the second monolithic layer opposite the first monolithic layer,
wherein the first monolithic layer comprises a first polyester including at least about 70 mole percent naphthalenedicarboxylate groups based on total carboxylate groups and including one or more catalysts having a total concentration by weight in a range of 10 to 1000 ppm;
wherein each of the first and third monolithic layers has a thickness in the range of about 5 μm to about 300 μm, and the second monolithic layer has a thickness greater than the thickness of the first monolithic layer; and
wherein each of the first and third monolithic layers is substantially free of light scattering, non-catalyst particulate matter.
2. The brightness enhancement film of claim 1 , further comprising a second microstructured layer disposed between the first microstructured layer and the first monolithic layer, the second microstructured layer including light diffusing microstructures.
3. The brightness enhancement film of claim 1 , further comprising a durable layer adjacent the first monolithic layer opposite the first microstructured layer.
4. The brightness enhancement film of claim 3 , wherein the durable layer has a microstructured surface, the microstructured surface including light diffusing microstructures.
5. The brightness enhancement film of claim 1 , wherein the first monolithic layer has an out-of-plane birefringence having an absolute value of at least about 0.15.
6. The brightness enhancement film of claim 1 ,
wherein the third monolithic layer comprises a second polyester including at least about 70 mole percent naphthalenedicarboxylate groups based on total carboxylate groups and including one or more catalysts having a total concentration by weight in a range of 10 to 1000 ppm.
7. The brightness enhancement film of claim 1 , further comprising a second microstructured layer adjacent the first monolithic layer opposite the first microstructured layer.
8. The brightness enhancement film of claim 7 , wherein the first plurality of microstructures include linear prisms extending in a first direction and the second microstructured layer includes a second plurality of microstructures, wherein the second plurality of microstructures include linear prisms extending in a second direction different from the first direction.
9. The brightness enhancement film of claim 1 , wherein the first monolithic layer has a haze less than about 1 percent.
10. A display comprising the brightness enhancement film of claim 1 .
11. A brightness enhancement film comprising:
a first monolithic layer;
a first microstructured layer adjacent the first monolithic layer, the first microstructured layer having a first major surface and an opposing second major surface, the first major surface comprising a first plurality of microstructures, and the second major surface facing the first monolithic layer;
a second monolithic layer immediately adjacent the first monolithic layer opposite the first microstructured layer; and
a third monolithic layer immediately adjacent the second monolithic layer opposite the first monolithic layer,
wherein the first monolithic layer comprises a first polyester including at least about 70 mole percent naphthalenedicarboxylate groups based on total carboxylate groups;
wherein each of the first and third monolithic layers has a thickness in the range of about 5 μm to about 300 μm, and the second monolithic layer has a thickness greater than the thickness of the first monolithic layer; and
wherein each of the first and third monolithic layers has a haze less than about 1 percent.
12. The brightness enhancement film of claim 11 , further comprising a second microstructured layer disposed between the first microstructured layer and the first monolithic layer, the second microstructured layer including light diffusing microstructures.
13. The brightness enhancement film of claim 11 , further comprising a durable layer adjacent the first monolithic layer opposite the first microstructured layer.
14. The brightness enhancement film of claim 13 , wherein the durable layer has a microstructured surface, the microstructured surface including light diffusing microstructures.
15. The brightness enhancement film of claim 11 , wherein the first monolithic layer has an out-of-plane birefringence having an absolute value of at least about 0.15.
16. The brightness enhancement film of claim 11 ,
wherein the third monolithic layer comprises a second polyester including at least about 70 mole percent naphthalenedicarboxylate groups based on total carboxylate groups.
17. The brightness enhancement film of claim 11 , further comprising a second microstructured layer adjacent the first monolithic layer opposite the first microstructured layer.
18. The brightness enhancement film of claim 17 , wherein the first plurality of microstructures include linear prisms extending in a first direction and the second microstructured layer includes a second plurality of microstructures wherein the second plurality of microstructures include linear prisms extending in a second direction different from the first direction.
19. The brightness enhancement film of claim 11 , wherein the first monolithic layer is substantially free of non-catalyst particulate matter.
20. The brightness enhancement film of claim 11 , wherein the first monolithic layer comprises one or more catalysts having a total concentration by weight in a range of 10 to 1000 ppm.
21. A display comprising the brightness enhancement film of claim 11 .
22. The brightness enhancement film of claim 11 having an overall thickness less than about 300 μm.
23. The brightness enhancement film of claim 1 having an overall thickness less than about 300 μm.