Protective film for display, production method thereof, and stretchable display apparatus

Patent metadata

Field	Value
Publication number	US-11513260-B2
Application number	US-201916390452-A
Country	US
Kind code	B2
Filing date	Apr 22, 2019
Priority date	Aug 31, 2018
Publication date	Nov 29, 2022
Grant date	Nov 29, 2022

Abstract

There are provided a protective film for display, a production method thereof, and a stretchable display apparatus. The protective film for display comprises: particles of a transparent resin, and a matrix of a transparent elastomer having an elastic modulus lower than that of the transparent resin, wherein the particles of the transparent resin are distributed in the matrix of the transparent elastomer, and when the protective film for display is stretched to reach a critical elongation, a craze occurs in the protective film for display.

First claim

What is claimed is:

1. A protective film for display, comprising:
particles of a transparent resin, wherein the transparent resin is selected from at least one of polyacrylates and polymethacrylates, and
a matrix of a transparent elastomer having an elastic modulus lower than that of the transparent resin, wherein the transparent elastomer is selected from at least one of polydimethylsiloxanes and thermoplastic polyurethanes,
wherein the particles of the transparent resin are distributed in the matrix of the transparent elastomer, and
when the protective film for display is stretched to reach a critical elongation, a craze occurs in the protective film for display, so that transparency changes,
wherein
when the protective film for display is not stretched to reach the critical elongation, the protective film for display is in a transparent status, wherein the transparency is not changed;
when the protective film for display is stretched to reach the critical elongation, the craze occurs in the protective film for display, so that the transparency decreases; and
after the craze occurs in the protective film for display due to that the critical elongation is reached, when the protective film for display is heated to a temperature no less than a glass transition temperature of the transparent resin, the craze disappears and the protective film for display is in a transparent status again.

2. The protective film for display of claim 1 , wherein the critical elongation is 5% to 150%.

3. The protective film for display of claim 1 , wherein the transparent resin has a glass transition temperature of 25° C. to 110° C.

4. The protective film for display of claim 1 , wherein a weight ratio of the particles of the transparent resin to the matrix of the transparent elastomer is 5:95 to 50:50.

5. The protective film for display of claim 1 , wherein the particle of the transparent resin has an average particle diameter of 0.01μm to 3 μm.

6. The protective film for display of claim 1 , wherein the transparent resin is selected from at least one of poly(methyl methacrylate), poly(tert-butyl acrylate), poly(n-propyl methacrylate), poly(ethyl methacrylate), poly(isobutyl methacrylate), poly(hydroxyethyl methacrylate), and poly(glycidyl methacrylate).

7. The protective film for display of claim 1 , further comprising: an interfacial compatibilizer.

8. The protective film for display of claim 7 , wherein the interfacial compatibilizer comprises at least one of nanosilica and nanoalumina.

9. The protective film for display of claim 7 , wherein the interfacial compatibilizer has a weight content of 0.01% to 10% in the protective film for display.

10. The protective film for display of claim 1 , wherein the protective film for display has a thickness of 25 μm to 1000 μm.

11. The protective film for display of claim 1 , wherein the particles of the transparent resin are uniformly distributed in the matrix of the transparent elastomer.

12. A method of producing the protective film for display of claim 1 , comprising:
extruding a mixture of the particles of the transparent resin and the matrix of the transparent elastomer in a form of a film at a temperature no less than a melting temperature of the mixture.

13. A stretchable display apparatus, comprising the protective film for display of claim 1 .

14. The stretchable display apparatus of claim 13 , wherein the stretchable display apparatus comprises a stretchable substrate, wherein the critical elongation is less than an elongation corresponding to a transition strain point of the stretchable substrate.

15. The stretchable display apparatus of claim 14 , wherein the critical elongation is 90% or less of an elongation corresponding to a transition strain point of the stretchable substrate.

16. The stretchable display apparatus of claim 13 , further comprising:
a stretchable display device; and
an electric heating layer;
wherein the electric heating layer is located between the protective film for display and the stretchable display device and is capable of heating the protective film for display to a temperature no less than a glass transition temperature of the transparent resin.

17. The protective film for display of claim 1 , wherein
the particles of the transparent resin are distributed in the matrix of the transparent elastomer to form a sea-island structure, wherein the sea phase is the matrix of the transparent elastomer, and island phases are the particles of the transparent resin, wherein crazes are generated in island phases, when the protective film for display is stretched to reach the critical elongation.

Assignees

• Boe Technology Group Co Ltd
• Beijing Boe Technology Dev Co Ltd

Inventors

• Wang Hejin
• Hsieh Mingche
• Wang Pinfan

Classifications

• C03C17/32

  with synthetic or natural resins (C03C17/30 takes precedence) · CPC title

• G06F1/1652 Primary

  the display being flexible, e.g. mimicking a sheet of paper, or rollable · CPC title

• H05B3/84

  Heating arrangements specially adapted for transparent or reflecting areas, e.g. for demisting or de-icing windows, mirrors or vehicle windshields · CPC title

• G09F9/301 Primary

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

• B32B27/40

  comprising polyurethanes · CPC title