Cover window and display device using the same

Patent metadata

Field	Value
Publication number	US-10522060-B2
Application number	US-201715720996-A
Country	US
Kind code	B2
Filing date	Sep 29, 2017
Priority date	Sep 30, 2016
Publication date	Dec 31, 2019
Grant date	Dec 31, 2019

Abstract

Disclosed are a cover window in which both a folding area and a non-folding area are formed using the same kind of material, thereby matching the indices of refraction thereof with each other, having the same heat resistance, and ensuring easy surface hard coating thereof, and a display device using the same. The cover window, having at least one folding area and a non-folding area, includes a hard portion located to correspond to the non-folding area, a soft portion located to correspond to the folding area, the soft portion being flexible, and a hard coating layer configured to cover the hard portion and the soft portion.

First claim

What is claimed is:

1. A cover window having at least one folding area and at least one non-folding area, comprising:
a soft portion being flexible and disposed to correspond to the at least one folding area and the non-folding area, wherein the soft portion corresponding to the at least one folding area has a height greater than that of the soft portion corresponding to the at least one non-folding area in an unfolded state;
a hard portion disposed on only a portion of the soft portion which corresponds to the at least one non-folding area; and
a hard coating layer configured to cover the hard portion and the soft portion,
wherein the hard coating layer directly contacts the soft portion corresponding to the at least one folding area, and
wherein the hard portion, the soft portion and the hard coating layer have substantially the same thermal characteristic that prevents the cover window from thermal expansion and bending.

2. The cover window according to claim 1 , wherein the soft portion is disposed to correspond to both the folding area and the non-folding area, and the soft portion corresponding to the non-folding area has a height lower than a height of the soft portion corresponding to the folding area.

3. The cover window according to claim 2 , wherein the hard portion is disposed between the soft portion and the hard coating layer, and a sum of heights of the soft portion and the hard portion, corresponding to the non-folding area, is the same as the height of the soft portion corresponding to the folding area.

4. The cover window according to claim 1 , wherein the soft portion, the hard portion and the hard coating layer are formed of the same kind of resin.

5. The cover window according to claim 4 , wherein the soft portion, the hard portion and the hard coating layer include a silicone-based resin.

6. The cover window according to claim 5 , wherein the soft portion includes a first silicone resin having a siloxane base.

7. The cover window according to claim 6 , wherein the soft portion includes the first silicone resin and a thermosetting initiator.

8. The cover window according to claim 5 , wherein the hard portion and the hard coating layer include a mixture of a second silicone resin and a third silicone resin, which have a hardness greater than that of the silicone resin of the soft portion.

9. The cover window according to claim 8 , wherein the second silicone resin includes a silicone resin based on a material in which at least one of an acryl side chain or an aliphatic side chain is coupled to a polysiloxane-based backbone.

10. The cover window according to claim 8 , wherein the third silicone resin includes a silicone resin based on a material in which a phenyl side chain is coupled to a siloxane-based backbone.

11. A method of manufacturing a cover window having a folding area and a non-folding area, comprising:
forming a soft portion having flexibility to dispose to correspond to the folding area and the non-folding area;
applying a mixture of a second silicone resin and a third silicone resin on the soft portion;
adding an ultraviolet curing initiator and a thermosetting initiator to the mixture;
curing the applied mixture with the added initiators by irradiating ultraviolet light to form a hard portion corresponding to the non-folding area; and
forming a hard coating layer to cover the hard portion and the soft portion,
wherein the soft portion corresponding to the folding area has a height greater than that of the soft portion corresponding to the non-folding area in an unfolded state,
wherein the hard portion is disposed on only a portion of the soft portion which corresponds to the at least one non-folding area;
wherein the hard coating layer directly contacts the soft portion corresponding to the at least one folding area, and
wherein the hard portion, the soft portion and the hard coating layer have substantially the same thermal characteristic that prevents the cover window from thermal expansion and bending.

12. The cover window according to claim 11 , further comprising thermosetting an area corresponding to the hard portion after the forming the hard coating layer.

13. The cover window according to claim 1 , wherein the hard portion has a portion in contact with the soft portion in the folding area, and the contact portion has a curvature.

14. The cover window according to claim 1 , wherein the hard portion and the soft portion have a difference in indices of refraction within 0.01.

15. A display device having a cover window, comprising:
a display panel having at least one folding area in a display area; a cover window on the display panel and having at least one folding area and at least one non-folding area;
a soft portion having flexibility and disposed to correspond to the folding area, wherein the soft portion corresponding to the folding area has a height greater than that of the soft portion corresponding to the non-folding area in an unfolded state;
a hard portion disposed on only a portion of the soft portion which corresponds to the at least one non-folding area; and
a hard coating layer covering the hard portion and the soft portion,
wherein the hard coating layer directly contacts the soft portion corresponding to the at least one folding area, and
wherein the hard portion, the soft portion and the hard coating layer have substantially the same thermal characteristic that prevents the cover window from thermal expansion and bending.

16. A cover window for a foldable display device having non-folding areas and a folding area between the non-folding areas, comprising:
a hard portion disposed to correspond to the non-folding area;
a soft portion having flexibility and disposed to correspond to the folding area, wherein the hard portion and the soft portion have a difference in indices of refraction small enough to prevent visibility at proximity of a boundary between the hard portion and the soft portion, and
wherein the soft portion corresponding to the folding area has a height greater than that of the soft portion corresponding to the non-folding areas in an unfolded state; and
a hard coating layer covering the hard portion and the soft portion,
wherein the hard coating layer directly contacts the soft portion corresponding to the at least one folding area, and
wherein the hard portion, the soft portion and the hard coating layer have substantially the same thermal characteristic that prevents the cover window from thermal expansion and bending.

17. The cover window according to claim 16 , wherein the difference in indices of refraction is equal to or less than 0.01.

18. The cover window according to claim 16 , wherein the hard portion has a contact portion with the soft portion in the folding area, and the contact portion has a curvature.

19. The cover window according to claim 18 , wherein the curvature has a radius of approximately half a thickness of the hard portion.

20. The cover window according to claim 16 , wherein the hard portion is disposed between the soft portion and the hard coating layer, and a sum of heights of the soft portion and the hard portion, corresponding to the non-folding area, is the same as the height of the soft portion corresponding to the folding area.

Assignees

• Lg Display Co Ltd

Inventors

• Park Young-Joo
• Jang Se-Jin
• WON Yu-Lim
• Choi Suk

Classifications

• G09F9/301 Primary

  flexible foldable or roll-able electronic displays, e.g. thin LCD, OLED · CPC title

• H05K1/028

  Bending or folding regions of flexible printed circuits (H05K1/0283 takes precedence) · CPC title

• Y02E10/549

  Organic PV cells · CPC title

• H01L2251/5338

  Electricity · mapped topic

• G09F9/33

  being semiconductor devices, e.g. diodes · CPC title