Multifunction light redirecting films

• US 20100075069A1
• Filed: 07/22/2009
• Published: 03/25/2010
• Est. Priority Date: 09/19/2008
• Status: Abandoned Application

• Current Assignee: SKC Haas Display Films Co., Ltd. (Dow, Inc.)
• Original Assignee: SKC Haas Display Films Co., Ltd. (Dow, Inc.)
• Inventors: Laney, Thomas M., Landry, Michael R., Lei, Herong
• Application Number:
  US12/460,601
• Publication Number:
  US 20100075069A1
• Time in Patent Office: Days
• US Class Current: 428/1.600
• CPC Class Codes: B32B 2250/24 All layers being polymeric
• CPC Class Codes: B32B 2255/10 on synthetic resin layer or on natural or synthetic rubber layer
• CPC Class Codes: B32B 2255/26 Polymeric coating
• CPC Class Codes: B32B 23/08 of synthetic resin
• CPC Class Codes: B32B 23/20 comprising esters
• CPC Class Codes: B32B 2307/202 Conductive
• CPC Class Codes: B32B 2307/30 having particular thermal properties
• CPC Class Codes: B32B 2307/308 Heat stability
• CPC Class Codes: B32B 2307/40 having particular optical properties
• CPC Class Codes: B32B 2307/402 Coloured
• CPC Class Codes: B32B 2307/41 Opaque
• CPC Class Codes: B32B 2307/412 Transparent
• CPC Class Codes: B32B 2307/416 Reflective
• CPC Class Codes: B32B 2307/50 having particular mechanical properties
• CPC Class Codes: B32B 2307/51 Elastic
• CPC Class Codes: B32B 2307/536 Hardness
• CPC Class Codes: B32B 2457/20 Displays, e.g. liquid crystal displays, plasma displays
• CPC Class Codes: B32B 2457/202 LCD, i.e. liquid crystal displays
• CPC Class Codes: B32B 27/08 of synthetic resin
• CPC Class Codes: B32B 27/281 comprising polyimides
• CPC Class Codes: B32B 27/302 : comprising aromatic vinyl (co)polymers, e.g. styrenic (co)polymers
• CPC Class Codes: B32B 27/304 : comprising vinyl halide (co)polymers, e.g. PVC, PVDC, PVF, PVDF
• CPC Class Codes: B32B 27/306 : comprising vinyl acetate or vinyl alcohol (co)polymers
• CPC Class Codes: B32B 27/308 : comprising acrylic (co)polymers
• CPC Class Codes: B32B 27/32 : comprising polyolefins comprising vinyl (co)polymers or acrylic (co)polymers B32B27/30
• CPC Class Codes: B32B 27/36 : comprising polyesters
• CPC Class Codes: B32B 27/365 : comprising polycarbonates
• CPC Class Codes: B32B 27/40 : comprising polyurethanes
• CPC Class Codes: B32B 3/30 : characterised by a layer formed with recesses or projections, e.g. hollows, grooves, protuberances, ribs apertured layer B32B3/266; layer with cavities or internal voids B32B3/26
• CPC Class Codes: B32B 7/12 : using interposed adhesives or interposed materials with bonding properties
• CPC Class Codes: C09K 2323/00 : Functional layers of liquid crystal optical display excluding electroactive liquid crystal layer characterised by chemical composition
• CPC Class Codes: C09K 2323/06 : Substrate layer characterised by chemical composition
• CPC Class Codes: G02B 6/0018 : Redirecting means on the surface of the light guide
• CPC Class Codes: G02B 6/002 : by shaping at least a portion of the light guide, e.g. with collimating, focussing or diverging surfaces
• CPC Class Codes: G02B 6/0065 : Manufacturing aspects; Material aspects

Abstract

The present invention provides a multifunction light redirecting film for a liquid crystal display comprising at least one base thermoplastic polymer optical layer having a top surface with a plurality of optical features. The film further provides at least one co-extrudable surface thermoplastic polymer optical layer adjacent the base thermoplastic polymer optical layer, wherein the at least one co-extrudable surface has a pencil hardness of at least 1 H.

Claims

1. A multifunction light redirecting film for a liquid crystal display comprising:

at least one base thermoplastic polymer optical layer having a top surface with a plurality of optical features;

at least one co-extrudable surface thermoplastic polymer optical layer adjacent the base thermoplastic polymer optical layer, wherein the at least one co-extrudable surface has a pencil hardness of at least 1 H.

2. The multifunction light redirecting film as recited in claim 1, wherein the at least one co-extruded surface layer comprises a polycarbonate copolymer and the at least one base layer comprises a polycarbonate.

3. A multifunction light redirecting film for a liquid crystal display comprising:

a polymeric optical core layer having a top side and a bottom side;

a top base thermoplastic polymer optical layer on the top side of the core layer;

a bottom base thermoplastic polymer optical layer on the bottom side of the core layer;

a light redirecting layer for substantially collimating visible light on the top base layer; and

wherein the core layer and the base layers comprise materials having a glass transition temperature (T_g) that is greater than approximately 70°

C.

5. The multifunction light redirecting film as recited in claim 5, further comprising at least one surface layer on the bottom base layer with a pencil hardness of at least 1 H.

4. The multifunction light redirecting film as recited in claim 5, wherein the core layer has a thickness of approximately 115 μ

m and a modulus of elasticity of approximately 5.0 GPa.

6. The multifunction light redirecting film as recited in claim 5, wherein the at least one surface layer comprises a polycarbonate copolymer, the top and bottom base layers is selected from the group comprising polycarbonate, polystyrene, polyester, cellulose triacetate, polypropylene, PEN or PMMA, and the core layer comprises a biaxially oriented polyester.

7. The multifunction light redirecting film as recited in claim 6, wherein one or more of each of the layers contain a hazing agent.

8. The multifunction light redirecting film as recited in claim 7, wherein the layer containing a hazing agent comprises a polycarbonate matrix polymer and the hazing agent is an immiscible polymer.

9. The multifunction light redirecting film as recited in claim 8, wherein the immiscible polymer is either polyethylene naphthalate or a copolymer of styrene and methyl-methacrylate.

10. The multifunction light redirecting film as recited in claim 5, further comprising an adhesive layer between the core layer and the top and bottom base layers.