Transparent composite film with hard coating, method for forming the same and flexible display device including the same

Patent metadata

Field	Value
Publication number	US-11414527-B2
Application number	US-201816607874-A
Country	US
Kind code	B2
Filing date	Apr 23, 2018
Priority date	Apr 26, 2017
Publication date	Aug 16, 2022
Grant date	Aug 16, 2022

Abstract

Described herein are articles and methods of making articles, including a transparent composite film having a fiber filler embedded in a polymer network and further including a hard coating. The polymer network of the film is a cured, cross-linked matrix. The hard coating is a cross-linked aromatic urethane acrylate oligomer and a photoinitiator and provides a flexible protective layer that maintains good hardness, puncture-resistance and scratch-resistance.

First claim

What is claimed is:

1. A flexible transparent composite film comprising:
a film of a composite composition, the composite composition comprising a cross-linked polymer network, a fiber filler embedded in the cross-linked polymer network, and an optional photoinitiator; and
a hard coating provided on one or both sides of the composite composition film, the hard coating comprising a cross-linked hard coating composition, the hard coating composition comprising an aromatic urethane acrylate oligomer and a photoinitiator;
wherein the flexible transparent composite film comprises a bend radius of less than about 5 mm and a Pencil Hardness greater than or equal to about 5 H.

2. The flexible transparent composite film of claim 1 , wherein the aromatic urethane acrylate oligomer is a multifunctional aromatic urethane acrylate oligomer.

3. The flexible transparent composite film of claim 1 , wherein the aromatic urethane acrylate oligomer comprises a number average molecular weight (MW) of from about 750 to about 2500.

4. The flexible transparent composite film of claim 1 , wherein a minimum number of acrylate functional groups (F) in the aromatic urethane acrylate oligomer follows the following equation:
F =MW/250,
wherein MW is a number average molecular weight of the aromatic urethane acrylate oligomer.

5. The flexible transparent composite film of claim 1 , wherein the hard coating composition further comprises a second aromatic urethane acrylate oligomer.

6. The flexible transparent composite film of claim 1 , wherein the cross-linked polymer network comprises one or more functional group.

7. The flexible transparent composite film of claim 6 , wherein the one or more functional group comprises acrylate, ester, ether, hydroxyl, or combinations thereof.

8. The flexible transparent composite film of claim 1 , wherein the photoinitiator is present in the hard coating and optionally present in the composite composition, in an amount from about 2 weight percent to about 6 weight percent, based on the weight of each of the hard coating and the composite composition.

9. The flexible transparent composite film of claim 8 , wherein the photoinitiator is present in the hard coating, in an amount from about 3 weight percent to about 5 weight percent, based on the weight of the hard coating.

10. The flexible transparent composite film of claim 9 , wherein the photoinitiator is present in the hard coating, in an amount of about 5 weight percent, based on the weight of the hard coating.

11. The flexible transparent composite film of claim 1 , wherein the hard coating comprises a coefficient of thermal expansion, at a temperature that is from 25° C. to 300° C., that is less than a coefficient of thermal expansion of the composite composition film.

12. The flexible transparent composite film of claim 1 , wherein the bend radius is less than about 2 mm.

13. The flexible transparent composite film of claim 1 , wherein the Pencil Hardness is greater than or equal to about 8 H.

14. The flexible transparent composite film of claim 1 , wherein the fiber filler comprises glass fibers.

15. The flexible transparent composite film of claim 1 , wherein the hard coating comprises an average thickness of less than or equal to about 25 μm.

16. The flexible transparent composite film of claim 1 , wherein the composite composition film comprises an average thickness of less than or equal to about 200 μm.

17. The flexible transparent composite film of claim 16 , wherein the composite composition film has an average thickness of less than or equal to about 55 μm.

18. The flexible transparent composite film of claim 1 , wherein the hard coating is provided on both sides of the composite composition film.

19. The flexible transparent composite film of claim 1 , wherein the fiber filler is a woven fiber fabric.

20. A consumer electronic product, comprising:
a housing comprising a front surface, a back surface and side surfaces;
electrical components at least partially within the housing, the electrical components comprising at least a controller, a memory, and a display, the display at or adjacent the front surface of the housing; and
a cover material disposed over the display,
wherein at least one of a portion of the housing or the cover material comprises the flexible transparent composite film of claim 1 .

21. A method for making a flexible transparent composite film comprising:
applying a resin composition onto a fiber filler, the resin composition comprising one or more acrylate-functionalized monomers and an optional photoinitiator;
at least partially curing the resin composition to form a film of a composite composition, the composite composition comprising an at least partially cross-linked polymer network, the fiber filler embedded in the at least partially cross-linked polymer network, and the optional photoinitiator;
applying a hard coating composition to one side of the composite composition film, the hard coating composition comprising one or more aromatic urethane acrylate oligomers and a photoinitiator;
at least partially curing the hard coating composition to form a first hard coating;
optionally applying the hard coating composition to the other side of the composite composition film, and at least partially curing the hard coating composition to form a second hard coating; and
finally curing the flexible transparent composite film;
wherein the flexible transparent composite film comprises a bend radius of less than about 5 mm and a Pencil Hardness greater than or equal to about 5 H.

Assignees

• Corning Inc

Inventors

• Hou Jun
• Mccarthy Kevin Robert

Classifications

• H04M1/0268

  including a flexible display panel · CPC title

• C09D175/16

  having terminal carbon-to-carbon unsaturated bonds · CPC title

• B32B2457/20

  Displays, e.g. liquid crystal displays, plasma displays · CPC title

• C08G18/8175

  with esters of acrylic or alkylacrylic acid having only one group containing active hydrogen · CPC title

• C08J5/043 Primary

  with glass fibres · CPC title