Electro-rheological fluid and haptic device

Patent metadata

Field	Value
Publication number	US-10160930-B2
Application number	US-201515125733-A
Country	US
Kind code	B2
Filing date	Feb 23, 2015
Priority date	Mar 14, 2014
Publication date	Dec 25, 2018
Grant date	Dec 25, 2018

Abstract

The present invention relates to an electro-rheological fluid comprising particles of at least one inorganic or organic material suspended in a polar liquid crystalline medium, the use of such electro-rheological fluid in an haptic device, an haptic device itself, a method of the production of such haptic device and the use of such haptic device in electro-optical devices.

First claim

The invention claimed is:

1. An electro-rheological fluid comprising particles of at least one inorganic or organic material suspended in a polar liquid crystalline medium exhibiting a dielectrically anisotropy of ≥5,
wherein said liquid-crystalline medium comprises one or more mesogenic compounds selected formulae I and/or I*:

wherein
L 11 to L 16 are independently of each other H or F,

are independently of each other,

R 11 is alkyl group, which is straight chain or branched, is unsubstituted, mono- or poly-substituted by F, Cl or CN, preferably by F, and in which one or more CH 2 groups are each optionally replaced, in each case independently from one another, by —O—, —S—, —NR 01 —, —SiR 01 R 02 —, —CO—, —COO—, —OCO—, —OCO—O—, —S—CO—, —CO—S—, —CY 01 ═CY 02 — or —C≡C— in such a manner that O and/or S atoms are not linked directly to one another,
Y 01 and Y 02 are, independently of each other, F, Cl, or CN, and alternatively one of Y 01 and Y 02 can be H,
R 01 and R 02 are, independently of each other, H, or alkyl with 1 to 12 C-atoms, and
X 11 halogen, CN, a mono-, di- or polyhalogenated alkyl-, or alkoxy group having 1 to 6 C-atoms or a mono-, di- or polyhalogenated alkenyl group having 2 to 6 C-atoms.

2. The electro-rheological fluid according to claim 1 , wherein the amount of particles of the inorganic or organic material in the electro-rheological fluid as a whole is in the range from 5 to 70% wt.

3. The electro-rheological fluid according to claim 1 , wherein the size of the particles of the inorganic or organic material is in the range from 1 nm to 1000 nm.

4. The electro-rheological fluid according to claim 1 , wherein said particles are of at least one inorganic material selected from amorphous silicon and TiO 2 .

5. The electro-rheological fluid according to claim 1 , wherein said particles are of at least one organic material selected from porous poly(methyl methacrylate, lithium polymethacrylate and styrene.

6. The electro-rheological fluid according to claim 1 , wherein said fluid comprises particles of at least one inorganic material suspended in said polar liquid crystalline medium.

7. The electro-rheological fluid according to claim 1 , wherein said fluid comprises particles of at least one organic material suspended in said polar liquid crystalline medium.

8. The electro-rheological fluid according to claim 1 , wherein the amount of said particles in the electro-rheological fluid as a whole is in the range from 5 to 70% wt.

9. The electro-rheological fluid according to claim 1 , wherein the amount of said liquid-crystalline medium in the electro-rheological fluid as a whole is in the range from 2 to 95% wt.

10. The electro-rheological fluid according to claim 1 , wherein said one or more mesogenic compounds of formula I and/or I* are selected from compounds of its sub-formulae I-1 and I-2:

11. The electro-rheological fluid according to claim 10 , wherein said liquid-crystalline medium further comprises one or more mesogenic compounds of formula III:

wherein
L 31 to L 33 are independently of one another H or F,
Z 31 is —COO— or —CF 2 O—,
R 31 is an alkyl group, which is straight chain or branched, is unsubstituted, mono- or poly-substituted by F, Cl or CN, preferably by F, and in which one or more CH 2 groups are each optionally replaced, in each case independently from one another, by —O—, —S—, —NR 01 —, —SiR 01 R 02 —, —CO—, —COO—, —OCO—, —OCO—O—, —S—CO—, —CO—S—, —CY 01 ═CY 02 — or —C≡C— in such a manner that O and/or S atoms are not linked directly to one another,
Y 01 and Y 02 are, independently of each other, F, Cl or CN, and alternatively one of Y 01 and Y 02 can be H,
R 01 and R 02 are, independently of each other, H or alkyl with 1 to 12 C-atoms, and
X 31 denotes halogen, CN, a mono- or polyhalogenated alkyl-, or alkoxy group having 1 to 6 C-atoms or a mono- or polyhalogenated alkenyl group having 2 to 6 C-atoms.

12. The electro-rheological fluid according to claim 11 , wherein said one or more mesogenic compounds of formula III are selected from compounds of formulae III-1 and/or III-2

wherein R 31 , L 31 to L 33 and X 31 have the meanings given in claim 11 .

13. The electro-rheological fluid according to claim 10 , wherein R H is n-alkyl.

14. The electro-rheological fluid according to claim 10 , wherein the concentration of the compounds of formulae I-1 and/or I-2 is in the range from 0.5% or more to 90% or less.

15. The electro-rheological fluid according to claim 10 , wherein the concentration of the compounds of formulae I-1 and/or I-2 is in the range from 1% or more to 80 or less.

16. The electro-rheological fluid according to claim 1 , wherein said liquid crystal medium comprises one or more mesogenic compounds selected formula I.

17. The electro-rheological fluid according to claim 1 , wherein said liquid crystal medium comprises one or more mesogenic compounds selected formula I*.

18. The electro-rheological fluid according to claim 17 , wherein

are independently of each other,

19. The electro-rheological fluid according to claim 17 , wherein said one or more mesogenic compounds of formula I are selected from sub-formulae I*-1 to I*-8:

wherein R 11 and X 11 are as defined in claim 17 .

20. The electro-rheological fluid according to claim 19 , wherein the concentration of the compounds of formulae I*-5 and/or I*-6 and/or I*-8 is in the range from 0.5% or more to 90% or less.

21. The electro-rheological fluid according to claim 19 , wherein the concentration of the compounds of formulae I*-5 and/or I*-6 and/or I*-8 is in the range from 1% or more to 80 or less.

22. The electro-rheological fluid according to claim 1 , wherein X 11 is F, Cl, CN, CF 3 , CHF 2 , OCF 3 , OCFHCF 3 , OCFHCHF 2 , OCF 2 CH 3 , OCF 2 CHF 2 , OCF 2 CF 2 CHF 2 , OCFHCF 2 CF 3 , OCFHCF 2 CHF 2 , OCF 2 CF 2 CF 3 , OCF 2 CF 2 CClF 2 , OCClFCF 2 CF 3 or CH═CF 2 .

23. The electro-rheological fluid according to claim 1 , wherein the concentration of the compounds of formulae I and/or I* is in the range from 0.5% or more to 90% or less.

24. The electro-rheological fluid according to claim 1 , wherein the concentration of the compounds of formulae I and/or I* is in the range from 1% or more to 80% or less.

25. The electro-rheological fluid according to claim 1 , wherein said liquid-crystalline medium further comprises one or more mesogenic compounds of formula II

Assignees

• Merck Patent Gmbh

Inventors

• Siemianowski Simon
• Tuffin Rachel
• Kemp Roger
• Sage Ian Charles

Classifications

• C10N2040/14

  Electric or magnetic purposes · CPC title

• C10N2050/015

  Dispersions of solid lubricants · CPC title

• C10N2030/06

  Oiliness; Film-strength; Anti-wear; Resistance to extreme pressure · CPC title

• C10N2020/06

  Particles of special shape or size · CPC title

• G06F3/016 Primary

  Input arrangements with force or tactile feedback as computer generated output to the user · CPC title