# US 10,308,744 B2 · Particles for electrophoretic displays

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 10,308,744 B2
- Document ID: US10308744B2
- Status: Granted
- Kind: B2
- Application number: 14/896,835
- Filed: 2014-05-20
- Published: 2016-05-19
- Granted: 2019-06-04
- Earliest claimed: 2013-06-12
- Assignees: Merck Patent GmbH; The Queen's University of Belfast
- Applicants: Merck Patent GmbH; The Queen's University of Belfast
- Inventors: Louise D. Farrand; Nils Greinert; Jonathan H. Wilson; Thomas Bauer; Claire Topping; Sarah Norman
- Web page: https://patentgrep.com/patent/US10308744B2

## CPC

- C08F 2/14: Organic medium
- C08F 2/26: anionic
- C08F 220/14: Methyl esters {, e.g. methyl (meth)acrylate}
- C09B 69/106: {containing an azo dye}
- C09D 5/4411: {Homopolymers or copolymers of acrylates or methacrylates}
- G02F 2001/1678: {characterised by the composition or particle type}
- C08F: MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C09B: ORGANIC DYES OR CLOSELY-RELATED COMPOUNDS FOR PRODUCING DYES {, e.g. PIGMENTS}; MORDANTS; LAKES (fermentation or enzyme using processes to synthesise a desired chemical compound C12P)
- C09D: COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR (cosmetics A61K; processes for applying liquids or other fluent materials to surfaces, in general, B05D; staining wood B27K5/02; glazes or vitreous enamels C03C; natural resins, French polish, drying-oils, driers, turpentine, per se, C09F; polishing compositions other than French polish, ski waxes C09G; adhesives or use of materials as adhesives C09J; materials for sealing or packing joints or covers C09K3/10; materials for stopping leaks C09K3/12; processes for the electrolytic or electrophoretic production of coatings C25D)
- G02F: OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS

## Abstract

This invention relates to polymer particles, a process for their preparation, electrophoretic fluids comprising such particles, and electrophoretic display devices comprising such fluids.

## Claims

### Claim 1

Polymer particles for use in electrophoretic devices comprising monomer units of
a) at least one ethylenically unsaturated monomer;
b) at least one polymerisable ionic liquid (PIL) selected from A to S listed below:
PIL
Cation
Anion
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
c) optionally at least one polymerisable dye, and
d) optionally at least one polymerisable steric stabilizer and
wherein the particles are spherical and have a diameter particle size in the range of 50-1200 nm.

### Claim 2 (depends on 1)

Polymer particles according to claim 1, wherein the polymerisable dye is present and is a dye of the formula (I′)-(VI′), or (VII)
wherein
R is H;
R1 and R2 are independently of one another alkyl, —OR′, —SR′, —C(O)R′, —C(O)OR′, —NHCOR′, —NO2, —CN, with R′ equal to H or alkyl;
L1 and L2 are independently of one another a single bond, C1-C6 alkyl, a polyether alkyl chain, or a combination thereof; and
Y1 and Y2 are methyl acrylate or methylmethacrylate;
X1, X2, and X3 are independently of one another H or an electron-withdrawing group;
R1 is H or OR′ with R′=a linear, branched or cyclic alkyl group;
R2 is a linear, branched or cyclic alkyl group;
R3 and R4 are independently of one another groups of the structure L3-Y3, L4-Y4;
L3, and L4 are linker groups and independently of one another linear or branched, substituted or unsubstituted alkylene groups where one or more non-adjacent carbon atoms is optionally replaced by O, S and/or N;
Y3, and Y4 are independently of one another polymerisable groups;
wherein at least one of R3 and R4 comprises a polymerisable group and at least one of X1, X2, and X3 is an electron-withdrawing group.

### Claim 3 (depends on 2)

Polymer particles according to claim 2, wherein
wherein R is H;
R1 and R2 are independently of one another —CH3, —NO2, —OH, —CN, —COCH3, —CO2CH2CH3, —NHCOR′;
L1 and L2 are, identical, C2-C4 alkyl, and
Y1 and Y2 are, identical, methyl acrylate or methyl methacrylate,
X1, X2, and X3 are independently of one another, an electron-withdrawing group selected from the group consisting of
NO2, CN, halogen, acyl, trifluoromethoxy, trifluoromethyl, SO2F, and CO2R, SO2R, SO2NRR and SO2NHR, with R being independently linear or branched C1-C4 alkyl, with at least one of X1, X2, and X3 is NO2, CN, Br, Cl, SO2NRR or SO2NHR and Y3 and Y4 are identical and are methacrylate or acrylate.

### Claim 4 (depends on 1)

Polymer particles according to claim 1, wherein the polymerisable dye is present and is a dye of the Dye 1 to Dye 19:
Dye 1
Dye 2
Dye 3
Dye 4
Dye 5
Dye 6
Dye 7
Dye 8
Dye 9
Dye 10
Dye 11
Dye 12
Dye 13
Dye 14
Dye 15
Dye 16
Dye 17
Dye 18
Dye 19

### Claim 5 (depends on 1)

Polymer particles according to claim 1, wherein the at least one polymerisable dye is present and the polymerisable dye is selected from the group consisting of monoazo dyes, disazo dyes, metallised dyes, anthraquinone dyes, phthalocyanine dyes, benzodifuranones dyes, Brilliant Blue derivatives, pyrroline dyes, squarilium dyes, triphendioxazine dyes and mixtures of these dyes.

### Claim 6 (depends on 1)

Polymer particles according to claim 1, wherein said at least one polymerisable ionic liquid is selected from the A, B, C, D, E, F, G, H, I, J, K, O, P, Q, or R.

### Claim 7 (depends on 1)

Polymer particles according to claim 1, wherein said at least one polymerisable dye is present, and said at least one polymerisable steric stabilizer is present.

### Claim 8 (depends on 1)

Polymer particles according to claim 1, wherein the polymerisable dye is present and is a dye of the formula (VIII)
wherein
X1, X2, and X3 are independently of one another H or an electron-withdrawing group;
R1 and R2 are independently of one another groups of the structure L1-Y1, L2-Y2 or linear, branched or cyclic alkyl groups;
R3 and R4 are independently of one another groups of the structure L3-Y3, L4-Y4 or linear, branched or cyclic, substituted or unsubstituted alkyl groups where one or more non-adjacent carbon atoms may be replaced by O, S and/or N;
L1, L2, L3, and L4 are linker groups and independently of one another linear or branched, substituted or unsubstituted alkylene groups where one or more non-adjacent carbon atoms may be replaced by O, S and/or N;
Y1, Y2, Y3, and Y4 are independently of one another polymerisable groups;
R′ is a linear or branched alkyl group, OR5, H, NHCOR6 or NHSO2R7;
R″ is OR5, H or NHCOR6,
R5, R6, and R7 are independently of one another linear or branched alkyl groups; and
wherein at least one of R1, R2, R3 and R4 is a polymerisable group and at least one of X1, X2, and X3 is an electron-withdrawing group.

### Claim 9 (depends on 1)

Polymer particles according to claim 1, wherein the ethyleneically unsaturated monomer is methacrylates and/or acrylates.

### Claim 10 (depends on 1)

Polymer particles according to claim 1, wherein the at least one polymerisable dye is present and the polymerisable dye is selected from azo dyes.

### Claim 11 (depends on 1)

Polymer particles according to claim 1, wherein the at least one polymerisable steric stabilizer is present and the polymerisable steric stabilizer is a poly(dimethylsiloxane) macromonomer with at least one polymerisable group and a molecular weight in the range of 1000-50000.

### Claim 12 (depends on 1)

Polymer particles according to claim 1, wherein the at least one polymerisable steric stabilizer is present and the polymerisable steric stabilizer is a mono-methacrylate terminated poly-dimethylsiloxane.

### Claim 13 (depends on 1)

Polymer particles according to claim 1, wherein the particles are spherical and have a diameter particle size in the range of 400-1000 nm.

### Claim 14 (depends on 1)

Polymer particles according to claim 1, wherein the particles are spherical and have a diameter particle size in the range 400-700 nm.

### Claim 15 (depends on 10)

Polymer particles according to claim 10, wherein the particles are spherical and have a diameter particle size in the range 400-700 nm, and with a monodisperse size distribution.

### Claim 16 (depends on 1)

A process for the preparation of polymer particles according claim 1, comprising
a) polymerizing said at least one ethylenically unsaturated monomer, said at least one polymerisable ionic liquid, at least one initiator, said at least one polymerisable dye, and said at least one polymerisable steric stabiliser by dispersion or emulsion polymerisation in a non-aqueous, non-polar solvent, and
b) optionally washing and drying the polymer particles.

### Claim 17 (depends on 16)

An electrophoretic fluid comprising polymer particles prepared by the process according to claim 16.

### Claim 18 (depends on 1)

An optical display, electrooptical display, electronic display, electrochemical display, electrophotographic display, electrowetting display, electrophoretic display, optical device, electrooptical device, electronic device, electrochemical device, electrophotographic device, electrowetting device, electrophoretic device, in security applications, cosmetic applications, decorative applications or diagnostic applications comprising polymer particles according to claim 1.

### Claim 19 (depends on 1)

A mono, bi or polychromal electrophoretic devices which comprises polymer particles according to claim 1.

### Claim 20 (depends on 1)

An electrophoretic fluid comprising polymer particles according to claim 1.

### Claim 21 (depends on 20)

An electrophoretic display device comprising an electrophoretic fluid according to claim 20.

### Claim 22 (depends on 21)

The electrophoretic display device according to claim 21, wherein the electrophoretic fluid is applied by a technique selected from inkjet printing, slot die spraying, nozzle spraying, flexographic printing, contact printing, contactless printing or deposition technique.