Lamination transfer films for forming articles with engineered voids

Patent metadata

Field	Value
Publication number	US-9246134-B2
Application number	US-201414159300-A
Country	US
Kind code	B2
Filing date	Jan 20, 2014
Priority date	Jan 20, 2014
Publication date	Jan 26, 2016
Grant date	Jan 26, 2016

Abstract

Transfer films, articles made therewith, and methods of making and using transfer films to form bridged nanostructures are disclosed.

First claim

What is claimed is:

1. A transfer film comprising:
a sacrificial template layer having a first surface and a second surface having a structured surface opposite the first surface;
a thermally stable backfill layer conforming to the structured surface of the sacrificial template layer;
wherein a portion of the sacrificial template layer proximate the first surface has a greater concentration of a thermally stable molecular species than a portion of the sacrificial template layer proximate the second surface.

2. The transfer film according to claim 1 , wherein the sacrificial template layer comprises a layer of thermally stable molecular species and the layer of thermally stable molecular species is separated from the structured surface of the sacrificial template layer by a layer of sacrificial material.

3. The transfer film according to claim 2 , wherein the layer of sacrificial material consists essentially of sacrificial material.

4. A method, comprising:
laminating a transfer film according to claim 3 to a receptor substrate;
baking out the sacrificial template layer to form engineered voids defined by a bridging layer and the structured surface of the thermally stable backfill layer, wherein the bridging layer is formed from the layer of thermally stable molecular species and the bridging layer is disposed on the structured surface.

5. The transfer film according to claim 1 , wherein the sacrificial template layer comprises a gradient of thermally stable molecular species and the gradient comprises a concentration of thermally stable molecular species that changes as a function of a distance from the structured surface along a thickness direction of the sacrificial template layer.

6. The transfer film according to claim 5 , wherein the concentration of thermally stable molecular species increases as a distance from the structured surface increases.

7. The transfer film according to claim 6 , wherein the concentration of thermally stable molecular species is greatest about the first surface.

8. The transfer film according to claim 5 , wherein the sacrificial template layer comprises a (meth)acrylic polymer.

9. The transfer film according to claim 8 , wherein the (meth)acrylic polymer comprises a majority of polyether segments or a majority of ethoxylated segments.

10. A method, comprising:
laminating a transfer film according to claim 5 to a receptor substrate;
baking out the sacrificial template layer to form engineered voids defined by a bridging layer and the structured surface of the thermally stable backfill layer, wherein the bridging layer is formed from the gradient of thermally stable molecular species within the sacrificial template layer and the bridging layer is disposed on the structured surface.

11. The transfer film according to claim 1 , wherein the thermally stable molecular species comprises silicon, aluminum, hafnium, barium, strontium, titanium, or zirconium.

12. The transfer film according to claim 1 , wherein the thermally stable molecular species comprises a metal or metal oxide or metal oxide precursor.

13. The transfer film according to claim 1 , wherein the thermally stable molecular species comprises an organosilicon polymer.

14. The transfer film according to claim 1 , wherein the thermally stable molecular species migrates from the thermally stable backfill layer into the sacrificial template layer.

15. The transfer film according to claim 1 , wherein the sacrificial template layer is capable of being baked out while leaving engineered voids defined by a bridging layer and the structured surface of the thermally stable backfill layer, wherein the bridging layer is formed from the thermally stable molecular species within the sacrificial template layer and the bridging layer is disposed on the structured surface.

16. The transfer film according to claim 1 , further comprising a support substrate having a releasable surface, the second surface of the sacrificial template layer disposed on the releasable surface of the support substrate.

17. A method, comprising:
laminating a transfer film according to claim 1 to a receptor substrate;
baking out the sacrificial template layer to form engineered voids defined by a bridging layer and the structured surface of the thermally stable backfill layer, wherein the bridging layer is formed from the thermally stable molecular species within the sacrificial template layer and the bridging layer is disposed on the structured surface.

18. The method according to claim 17 , wherein the receptor substrate comprises sapphire.

19. A bottom emitting OLED comprising:
a light transparent support layer;
a nanostructured layer on the support substrate, the nanostructured layer comprising a structured surface layer and a bridging layer on the structured surface layer and defining a plurality of engineered voids; and
an OLED structure disposed on the bridging layer, the OLED structure comprising a OLED layer separating a top electrode and a bottom electrode.

20. The bottom emitting OLED according to claim 19 wherein the structured surface layer has a refractive index of 1.5 or less and the bridging layer has a refractive index of 1.6 or greater.

21. A top emitting OLED comprising:
a support layer;
an OLED structure disposed on the support layer, the OLED structure comprising a OLED layer separating a top electrode and a bottom electrode;
a planarizing layer disposed on the top electrode;
a nanostructured layer on the OLED structure, the nanostructured layer comprising a structured surface layer and a bridging layer on the structured surface layer and defining a plurality of engineered voids, wherein the bridging layer is adjacent to the OLED structure; and
a light transparent layer disposed on the structured surface layer.

22. The top emitting OLED according to claim 21 wherein the structured surface layer has a refractive index of 1.5 or less and the bridging layer has a refractive index of 1.6 or greater.

23. The top emitting OLED according to claim 21 wherein the nanostructured layer is optically coupled to the OLED structure via an optical coupling and planarizing layer.

24. The top emitting OLED according to claim 21 wherein the nanostructured layer is not optically coupled to the OLED structure.

Assignees

• 3M Innovative Properties Co

Inventors

• Schwartz Evan L
• Meyer Justin P
• Benson Jr Olester
• Collier Terry O
• Free Michael Benton
• Kamrath Robert F
• Mazurek Mieczyslaw H
• Olson David B
• Shenoy K Raveesh
• Wolk Martin B

Classifications

• H10K50/858

  comprising refractive means, e.g. lenses · CPC title

• B29D11/00788

  Producing optical films · CPC title

• H10K50/86 Primary

  Arrangements for improving contrast, e.g. preventing reflection of ambient light · CPC title

• B32B3/263

  characterised by a layer having non-uniform thickness · CPC title

• H10K59/879

  comprising refractive means, e.g. lenses · CPC title