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US3963638A Expired / Lapsed US ⏱️ 0.0 years remaining

Liquid crystal compositions, methods and devices

Assignee: Eastman Kodak Co
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Filing: 1974-01-08
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Granted: 1976-06-15
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Expires: 1994-01-08
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Abstract

Abstract Dynamic scattering of nematic liquid crystalline compositions is enhanced by the addition of minor amounts of soluble salts having an organic carboxylate or organic sulfonate anion. The addition of these salts results in a lowering of the operating voltages necessary to obtain dynamic scattering.

Inventors

  • 👤 Hermann K. Bucher
  • 👤 Thomas R. Criswell

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 00:48
CPC Classifications
C; C09; C09K; C09K19/00; C09K19/52; C09K19/58; C09K19/582

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 168 words
A nematic liquid crystal composition which exhibits dynamic scattering upon subjecting a thin film of said composition to an electrical potential, said composition comprising: at least one nematic liquid crystalline compound having a negative dielectric anisotropy and an amount of an organic salt effective to aid dynamic scattering, said salt being soluble in said composition and having the formula: M +RX - wherein M + is a cation aiding solubility of said salt in said composition, said cation having the structure (R'") 4 N + in which (a) each R'" is an alkyl group with the total carbon atom content of all four R'" groups being at least 11 or (b) any three of R'" taken together represent the carbon atoms necessary to complete a 6- to 10-membered heterocyclic nucleus and the fourth R'" represents an alkyl group of about 8 to 24 carbon atoms; and RX - represents an anion selected from the group consisting of p-chlorobenzenesulfonate, p-nitrobenzenesulfonate, 2,5-dichlorobenzenesulfonate, p-bromobenzenesulfonate, 2-chloro-5-methylbenzenesulfonate, 2-methyl-5-nitrobenzenesulfonate, 2-chloro-5-nitrobenzenesulfonate, 2-chloro-3,5-dinitrobenzenesulfonate, pentafluorobenzoate, and 2-naphthalenesulfonate.
Claim 2
Dependent Claim 168 words
A nematic liquid crystal composition which exhibits dynamic scattering upon subjecting a thin film of said composition to an electrical potential, said composition comprising: at least one nematic liquid crystalline compound having a negative dielectric anisotropy and an amount of an organic salt effective to aid dynamic scattering, said salt being soluble in said composition and having the formula: M +RX - wherein M + is a cation aiding solubility of said salt in said composition, said cation having the structure (R'") 4 N + in which (a) each R'" is an alkyl group with the total carbon atom content of all four R'" groups being at least 11 or (b) any three of R'" taken together represent the carbon atoms necessary to complete a 6- to 10-membered heterocyclic nucleus and the fourth R'" represents an alkyl group of about 8 to 24 carbon atoms; and RX - represents an anion selected from the group consisting of p-chlorobenzenesulfonate, p-nitrobenzenesulfonate, 2,5-dichlorobenzenesulfonate, p-bromobenzenesulfonate, 2-chloro-5-methylbenzenesulfonate, 2-methyl-5-nitrobenzenesulfonate, 2-chloro-5-nitrobenzenesulfonate, 2-chloro-3,5-dinitrobenzenesulfonate, pentafluorobenzoate, and 2-naphthalenesulfonate.
Claim 3
Dependent Claim 21 words
A composition in accordance with claim 1 wherein said anion is selected from the group consisting of 2-chloro-5-nitrobenzenesulfonate, 2-chloro-3,5-dinitrobenzenesulfonate, and pentafluorobenzoate.
Claim 4
Dependent Claim 15 words
A composition as described in claim 1 in which RX - represents the anion 2-chloro-5-nitrobenzenesulfonate.
Claim 5
Dependent Claim 15 words
A composition as described in claim 1 in which RX - represents the anion 2-chloro-3,5-dinitrobenzenesulfonate.
Claim 6
Dependent Claim 15 words
A composition as described in claim 1 in which RX - represents the anion pentafluorobenzoate.
Claim 7
Dependent Claim 34 words
A composition as described in claim 1 wherein said salt is present at a concentration of about 10 - 4 to 10 - 7 mole of salt per average mole of liquid crystalline compound.
Claim 8
Dependent Claim 39 words
A nematic liquid crystal composition in accordance with claim 1 wherein in said structure (R'") 4 N + each R'" is an alkyl group with the total carbon atom content of all four R'" groups being at least 11.
Claim 9
Dependent Claim 148 words
In an electro-optical display device comprising two closely spaced conductive walls having therebetween a nematic liquid crystalline composition which has a negative dielectric anisotropy, the improvement wherein said composition has dissolved therein a soluble organic salt of the formula: M +RX - wherein M + is a cation aiding solubility of said salt in said composition, said cation having the structure (R'") 4 N + in which (a) each R'" is an alkyl group with the total carbon atom content of all four R'" groups being at least 11 or (b) any three of R'" taken together represent the carbon atoms necessary to complete a 6- to 10-membered heterocyclic nucleus and the fourth R'" represents an alkyl group of about 8 to 24 carbon atoms; and RX - represents an anion selected from the group consisting of p-chlorobenzenesulfonate, p-nitrobenzenesulfonate, 2,5-dichlorobenzenesulfonate, p-bromobenzenesulfonate, 2-chloro-5-methylbenzenesulfonate, 2-methyl-5-nitrobenzenesulfonate, 2-chloro-5-nitrobenzenesulfonate, 2-chloro-3,5-dinitrobenzenesulfonate, pentafluorobenzoate, and 2-naphthalenesulfonate.
Claim 10
Dependent Claim 148 words
In an electro-optical display device comprising two closely spaced conductive walls having therebetween a nematic liquid crystalline composition which has a negative dielectric anisotropy, the improvement wherein said composition has dissolved therein a soluble organic salt of the formula: M +RX - wherein M + is a cation aiding solubility of said salt in said composition, said cation having the structure (R'") 4 N + in which (a) each R'" is an alkyl group with the total carbon atom content of all four R'" groups being at least 11 or (b) any three of R'" taken together represent the carbon atoms necessary to complete a 6- to 10-membered heterocyclic nucleus and the fourth R'" represents an alkyl group of about 8 to 24 carbon atoms; and RX - represents an anion selected from the group consisting of p-chlorobenzenesulfonate, p-nitrobenzenesulfonate, 2,5-dichlorobenzenesulfonate, p-bromobenzenesulfonate, 2-chloro-5-methylbenzenesulfonate, 2-methyl-5-nitrobenzenesulfonate, 2-chloro-5-nitrobenzenesulfonate, 2-chloro-3,5-dinitrobenzenesulfonate, pentafluorobenzoate, and 2-naphthalenesulfonate.
Claim 11
Dependent Claim 39 words
In an electro-optical display device in accordance with claim 8, wherein in said structure (R'") 4 N + each R'" is an alkyl group with the total carbon atom content of all four R'" groups being at least 11.
Claim 12
Independent Claim 162 words
A method of enhancing the dynamic scattering properties of a nematic liquid crystalline composition which has a negative dielectric anisotropy comprising the step of adding to said composition about 10 - 4 to 10 - 7 mole of dopant per average mole of said composition, said dopant comprising a soluble organic salt having the formula: M +RX - in which M + is a cation aiding solubility in said composition, said cation having the structure (R'") 4 N + in which (a) each R'" is an alkyl group with the total carbon atom content of all four R'" groups being at least 11 or (b) any three of R'" taken together represent the carbon atoms necessary to complete a 6- to 10-membered heterocyclic nucleus and the fourth R'" represents an alkyl group of about 8 to 24 carbon atoms; and RX - represents an anion selected from the group consisting of p-chlorobenzenesulfonate, p-nitrobenzenesulfonate, 2,5-dichlorobenzenesulfonate, p-bromobenzenesulfonate, 2-chloro-5-methylbenzenesulfonate, 2-methyl-5-nitrobenzenesulfonate, 2-chloro-5-nitrobenzenesulfonate, 2-chloro-3,5-dinitrobenzenesulfonate, pentafluorobenzoate, and 2-naphthalenesulfonate.
Claim 13
Independent Claim 162 words
A method of enhancing the dynamic scattering properties of a nematic liquid crystalline composition which has a negative dielectric anisotropy comprising the step of adding to said composition about 10 - 4 to 10 - 7 mole of dopant per average mole of said composition, said dopant comprising a soluble organic salt having the formula: M +RX - in which M + is a cation aiding solubility in said composition, said cation having the structure (R'") 4 N + in which (a) each R'" is an alkyl group with the total carbon atom content of all four R'" groups being at least 11 or (b) any three of R'" taken together represent the carbon atoms necessary to complete a 6- to 10-membered heterocyclic nucleus and the fourth R'" represents an alkyl group of about 8 to 24 carbon atoms; and RX - represents an anion selected from the group consisting of p-chlorobenzenesulfonate, p-nitrobenzenesulfonate, 2,5-dichlorobenzenesulfonate, p-bromobenzenesulfonate, 2-chloro-5-methylbenzenesulfonate, 2-methyl-5-nitrobenzenesulfonate, 2-chloro-5-nitrobenzenesulfonate, 2-chloro-3,5-dinitrobenzenesulfonate, pentafluorobenzoate, and 2-naphthalenesulfonate.
Claim 14
Dependent Claim 36 words
A method in accordance with claim 10, wherein in said structure (R'") 4 M + each R'" is an alkyl group with the total carbon atom content of all four R'" groups being at least 11.

References Cited (Backward Citations)

US3656834A Cited
US3803050A Cited
US3838059A Cited
US3809456A Cited
US3814700A Cited
US3888566A Cited
US3920576A Cited
US3882039A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-06-15 1979-12-15 1980-06-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-06-15 1983-12-15 1984-06-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-06-15 1987-12-15 1988-06-15 $7700.00 Window Closed / Lapsed

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