Electrophoretic particles, method for manufacturing electrophoretic particles, electrophoresis dispersion, display device, and electronic apparatus

Patent metadata

Field	Value
Publication number	US-9323126-B2
Application number	US-201414287828-A
Country	US
Kind code	B2
Filing date	May 27, 2014
Priority date	Jun 4, 2013
Publication date	Apr 26, 2016
Grant date	Apr 26, 2016

Abstract

There is provided electrophoretic particle which has core particle, and a siloxane-based compound which includes a connecting structure in which a plurality of siloxane bonds are connected in series, and the surface of the core particle includes a first region to which the siloxane-based compound is bonded, and a second region in which charging characteristic derived from the core particle is expressed by exposure of the surface of the core particle. An occupancy rate of the first region on the surface of the core particle is preferably equal to greater than 0.05% and equal to or less than 20%.

First claim

What is claimed is:

1. An Electrophoretic particle, comprising:
a particle; and
a siloxane-based compound which is bonded to surface of the particle, and includes a connecting structure in which a plurality of siloxane bonds are connected in series,
wherein the surface of the particle includes a first region to which the siloxane-based compound is bonded, and a second region in which the surface is exposed.

2. The electrophoretic particle according to claim 1 ,
wherein a content of the siloxane-based compound is equal to or greater than 0.1 parts by mass and equal to or less than 5 parts by mass with respect to 100 parts by mass of the particle.

3. The electrophoretic particle according to claim 1 ,
wherein an occupancy rate of the first region on the surface of the particle is equal to or greater than 0.05% and equal to or less than 20%.

4. The electrophoretic particle according to claim 3 ,
wherein when the occupancy rate of the first region on the surface of the particle is A 1 , and an occupancy rate of the second region on the surface of the particle is A 2 , A 1 /A 2 is equal to or greater than 0.0005 and equal to or less than 0.1.

5. The electrophoretic particle according to claim 1 ,
wherein the siloxane-based compound has a linear molecular structure configured with a main chain including the connecting structure and a side chain bonded to the main chain.

6. The electrophoretic particle according to claim 1 ,
wherein the siloxane-based compound is a compound obtained by a method in which a silicone oil and a coupling agent are reacted, and a hydrolyzable group derived from the coupling agent of the obtained reaction product and the surface of the particle are subjected to a dehydration condensation reaction.

7. The electrophoretic particle according to claim 1 ,
wherein the siloxane-based compound is a compound obtained by a reaction of a functional group derived from the silicone oil and the surface of the particle.

8. The electrophoretic particle according to claim 6 ,
wherein the siloxane-based compound has a functional group capable of bonding to the surface of the particle at a terminal of one side of the connecting structure in a state before the siloxane-based compound is reacted with the surface of the particle.

9. The electrophoretic particle according to claim 1 ,
wherein a weight average molecular weight of the siloxane-based compound is equal to or greater than 1,000 and equal to or less than 100,000.

10. The electrophoretic particle according to claim 1 ,
wherein a constituent material of the surface of the particle includes an inorganic material, and the charging characteristic is based on a hydroxyl group present on the surface.

11. The electrophoretic particle according to claim 1 ,
wherein the constituent material of the surface of the particle includes an organic material having a dissociable group, and the charging characteristic is based on the dissociable group present on the surface.

12. A method for manufacturing electrophoretic particle, comprising:
obtaining a reaction product by reacting a siloxane bond-containing material with a coupling agent; and
bonding a siloxane-based compound derived from the reaction product to a part of surface of a particle by reacting a hydrolyzable group derived from the coupling agent of the reaction product with the surface.

13. An electrophoresis dispersion, comprising:
electrophoretic particle which have particle and a siloxane-based compound, and is configured such that surface of the particle includes a first region to which a siloxane-based compound is bonded, and a second region in which charging characteristics derived from the particle is expressed by exposure of the surface; and
a dispersion medium having a dielectric constant of equal to or greater than 1.5 and equal to or less than 3 which disperses the electrophoretic particle.

14. A display device, comprising:
an electrode substrate equipped with a substrate and an electrode;
the electrophoresis dispersion according to claim 13 ; and
a dispersion enclosing space provided at one surface side of the electrode substrate which encloses the electrophoresis dispersion.

15. An electronic apparatus comprising the display device according to claim 14 .

Assignees

• Seiko Epson Corp

Inventors

• Nakazawa Masahiko
• Yokokawa Shinobu

Classifications

• G02F1/167 Primary

  by electrophoresis · CPC title

• G02F2202/022

  polymeric · CPC title

• G02F1/0018

  Electro-optical materials · CPC title

• G02F2202/02

  organic material · CPC title

• G02F1/133348

  Charged particles addressed liquid crystal cells, e.g. controlled by an electron beam · CPC title