Display medium and display device

• US 8,477,404 B2
• Filed: 03/05/2009
• Issued: 07/02/2013
• Est. Priority Date: 09/25/2008
• Status: Active Grant

• Current Assignee: E Ink Holdings Incorporated
• Original Assignee: Fuji Xerox Company Limited (Xerox Holdings Corp.)
• Inventors: Moriyama, Hiroaki, Machida, Yoshinori, Yamamoto, Yasuo, Akashi, Ryojiro, Imai, Akira
• Primary Examiner(s): TRA, TUYEN Q
• Application Number:
  US12/398,832
• Publication Number:
  US 20100073281A1
• Time in Patent Office: 1,580 Days
• Field of Search: 359/296, 252/582, 252/586, 430/32, 430/34, 430/38, 204/450, 204/600, 345/107, 345/105
• US Class Current: 359/296
• CPC Class Codes: G02F 1/167 by electrophoresis
• CPC Class Codes: G02F 1/1675 Constructional details
• CPC Class Codes: G02F 1/1685 Operation of cells; Circuit arrangements affecting the entire cell

Abstract

A display medium includes: a pair of substrates having electrodes and disposed to form a space therebetween, at least one of the substrates transmitting light; a dispersion medium enclosed between the substrates; a group of particles that is dispersed in the dispersion medium and that moves in the dispersion medium according to an electric field applied between the substrates; and a treatment layer provided on at least one of surfaces of the substrates that oppose each other, the treatment layer being formed by treating the at least one of surfaces of the substrates that oppose each other with a polymer compound having a silicone chain.

Claims

1. A display medium comprising:

a pair of substrates having electrodes and disposed to form a space therebetween, at least one of the substrates transmitting light;

a dispersion medium enclosed between the substrates;

a group of particles that is dispersed in the dispersion medium and that moves in the dispersion medium according to an electric field applied between the substrates; and

a treatment layer provided on at least one of surfaces of the substrates that oppose each other, the treatment layer comprising a polymer compound having a silicone chain as a side chain thereof.

2. The display medium according to claim 1, wherein the polymer compound having a silicone chain is a reactive silicone polymer compound.

3. The display medium according to claim 2, wherein the reactive silicone polymer compound is a copolymer of monomers including, at least, a monomer having a silicone chain and a monomer having a reactive group.

4. The display medium according to claim 3, wherein the copolymerization ratio of the monomer having a silicone chain is 50% by weight or more with respect to the weight of the copolymer.

5. The display medium according to claim 3, wherein the copolymerization ratio of the monomer having a silicone chain is 80% by weight or more with respect to the weight of the copolymer.

6. The display medium according to claim 3, wherein the copolymerization of the monomer having a reactive group is in the range of from 0.1% by weight to 10% by weight with respect to the weight of the copolymer.

7. The display medium according to claim 3, wherein the monomer having a reactive group is glycidyl(meth)acrylate having an epoxy group or an isocyanate monomer having an isocyanate group.

8. The display medium according to claim 2, wherein the treatment layer has a thickness of about 0.001 μ

m to 10 μ

m.

9. The display medium according to claim 1, wherein the polymer compound having a silicone chain is a non-reactive silicone polymer compound.

10. The display medium according to claim 9, wherein the non-reactive silicone polymer compound is a copolymer of monomers including at least a monomer having a silicone chain and a monomer having no reactive group.

11. The display medium according to claim 10, wherein the copolymerization ratio of the monomer having a silicone chain is from 0.01% to 95% by weight with respect to the weight of the copolymer.

12. The display medium according to claim 10, wherein the copolymerization ratio of the monomer having a silicone chain is from 0.1% to 80% by weight with respect to the weight of the copolymer.

13. The display medium according to claim 9, wherein the treatment layer has a thickness of about 0.01 μ

m to 10 μ

m.

14. The display medium according to claim 1, wherein the pair of substrates are a display substrate and a rear substrate, and the treatment layer is formed at least on a surface of the display substrate opposing the rear substrate.

15. The display medium according to claim 1, further comprising a spacing member partitioning the space between the substrates and having the treatment layer on a surface thereof.

16. The display medium according to claim 1, wherein the dispersion medium is silicone oil.

17. The display medium according to claim 1, further comprising, in the dispersion medium, another group of particles having a larger volume average particle diameter than the group of particles and having a different optical reflection properties from the group of particles.

18. A display device comprising:

the display medium according to claim 1; and

a voltage applying unit that applies a voltage between the substrates.