Electrophoretic particle, method of manufacturing electrophoretic particle, electrophoresis dispersion liquid, electrophoresis sheet, electrophoresis device, and electronic apparatus

Patent metadata

Field	Value
Publication number	US-10597541-B2
Application number	US-201816143022-A
Country	US
Kind code	B2
Filing date	Sep 26, 2018
Priority date	Sep 18, 2015
Publication date	Mar 24, 2020
Grant date	Mar 24, 2020

Abstract

An electrophoretic particle includes a base particle (particle), a first compound, a second compound, and a third compound bonded to the base particle. The first compound is a polymer having a dispersion portion derived from a first monomer, and a bonding portion derived from a second monomer, and is connected to the base particle at the bonding portion. The second compound includes a non-polar group and a second functional group and is connected to the base particle at the second functional group. The third compound includes a charging group and a second functional group and is connected to the base particle at the second functional group.

First claim

What is claimed is:

1. An electrophoretic particle, comprising:
a particle including a first functional group on a surface; and
a first compound, a second compound, and a third compound bonded to the particle,
wherein the first compound is a block copolymer that includes a dispersion portion derived from a first monomer including a site that contributes to dispersibility in a dispersion medium, and a bonding portion derived from a second monomer including a second functional group having reactivity with the first functional group, and is connected to the particle by reacting the first functional group and the second functional group in the bonding portion,
the second compound has a lower molecular weight than the first compound, includes a non-polar group and a third functional group, and is connected to the particle by the third functional group reacting with the first functional group, and
the third compound has a lower molecular weight than the first compound, includes a charging group and a fourth functional group, and is connected to the particle by the fourth functional group reacting with the first functional group.

2. The electrophoretic particle according to claim 1 , wherein the second compound is a silane coupling agent that includes the non-polar group and the second functional group.

3. The electrophoretic particle according to claim 1 , wherein the second compound is a block copolymer that includes a non-polar portion derived from a third monomer including the non-polar group, and the bonding portion derived from a fourth monomer including the third functional group.

4. The electrophoretic particle according to claim 1 , wherein the non-polar group is a hydrocarbon group.

5. The electrophoretic particle according to claim 1 , wherein the molecular weight of the second compound is 100 or more to 1,000 or less.

6. The electrophoretic particle according to claim 1 , wherein the third compound is a silane coupling agent that includes the charging group and the fourth functional group.

7. The electrophoretic particle according to claim 1 , wherein the third compound is a block copolymer that includes a charging portion derived from the third monomer including the charging group, and the bonding portion derived from a fifth monomer including the fourth functional group.

8. The electrophoretic particle according to claim 1 , wherein the charging group includes at least one of a polarization group and an ionic group.

9. The electrophoretic particle according to claim 1 , wherein the molecular weight of the third compound is 100 or more to 1,000 or less.

10. The electrophoretic particle according to claim 1 , wherein, in the first compound, the bonding portion is formed by 1 or more to 10 or less units derived from the second monomer.

11. The electrophoretic particle according to claim 1 , wherein, in the first compound, the first monomer is a silicone macromonomer represented by the following general formula (I)

[in the formula, R1 is a hydrogen atom or a methyl group, R2 is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, R3 is a structure including one type from an alkyl group having 1 to 6 carbon atoms and an ether group of ethylene oxide or propylene oxide, and n is an integer of 0 or more].

12. The electrophoretic particle according to claim 1 , wherein the weight average molecular weight of the dispersion portion is 10,000 or more to 100,000 or less.

13. The electrophoretic particle according to claim 1 , wherein, when the weight average molecular weight of the dispersion portion is A and the molecular weight of the second compound is B, A/B is 10 or more to 1,000 or less.

14. A method of manufacturing an electrophoretic particle according to claim 1 , the method comprising:
connecting the third compound to the particle by reacting the first functional group included in the surface of the particle and the fourth functional group included in the third compound;
connecting the first compound to the particle at the bonding portion by reacting the first functional group included in the surface of the particle and the second functional group included in the first compound; and
connecting the second compound to the particle by reacting the first functional group included in the surface of the particle and the third functional group included in the second compound.

15. An electronic apparatus comprising:
a substrate; and
a structure that is provided on the substrate that accommodates an electrophoresis dispersion liquid comprising a dispersion medium and the electrophoretic particles according to claim 1 .

16. The electrophoretic particle according to claim 3 , wherein the fourth monomer is the same as the second monomer.

17. The electrophoretic particle according to claim 7 , wherein the fifth monomer is the same as the second monomer.

18. The electrophoretic particle according to claim 1 , wherein the second functional group is the same as at least one of the third and fourth functional groups.

19. The electrophoretic particle according to claim 1 , wherein the third functional group is the same as the fourth functional group.

Assignees

• E Ink Corp

Inventors

• Inoue Keiichi
• Nakamura Kiyoshi
• Yokokawa Shinobu
• Ushiyama Tomoyuki
• Nakazawa Masahiko

Classifications

• C08G77/20

  containing silicon bound to unsaturated aliphatic groups · CPC title

• G02F2001/1678

  characterised by the composition or particle type · CPC title

• G02F1/172

  based on a suspension of orientable dipolar particles, e.g. suspended particles displays · CPC title

• C09D5/448

  characterised by the additives used (C09D5/4403 - C09D5/4476, C09D5/4492 take precedence) · CPC title

• C09D5/44

  for electrophoretic applications (processes for coating by electrophoresis C25D13/00) · CPC title