EP0550105A2
Expired / Lapsed
EP
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Liquid-crystalline polyurethanes, compositions of said liquid-crystalline polyurethanes, and a device for optical data storage comprising a liquid-crystalline polyurethane
Assignee: Akzo Nobel NV
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Filing: 1992-12-21
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Granted: —
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Expires: 2012-12-21
Abstract
Abstract The invention relates to a liquid-crystalline polyurethane having a side chain comprising a mesogenic group, giving a clear polyurethane which does not isomerise under the influence of light. Such liquid-crystalline polyurethanes are highly suited to be used for optical data storage. The invention further relates to infrared-sensitive liquid-crystalline polyurethanes and liquid-crystalline polyurethane compositions, films containing said liquid-crystalline polyurethanes or polyurethane compositions, and a device for optical data storage containing said liquid-crystalline polyurethanes or polyurethane compositions.
Inventors
- 👤 Paulus Pieter De Wit
- 👤 Erwin Wilhelmus Petrus Erdhuisen
- 👤 John Bernard Reesink
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 19:52
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/241; G11B7/242; G11B7/244; G11B7/25; C; C08; C08G; C08G71/00; C08G71/04; C08G18/00; C08G18/06; C08G18/28; C08G18/30; C08G18/32; C08G18/3203; C08G18/3215; C08G18/3221; C08G18/38; C08G18/3819; C08G18/3838; C08G18/3842; C08G18/3848; C09; C09K; C09K19/00; C09K19/04; C09K19/38; C09K19/3833; C09K19/3885; C08G2250/00; C09K2323/00; C09K2323/03; C09K2323/031
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
119 words
A liquid-crystalline side chain polyurethane, characterised in that in the side chain it contains a mesogenic group satisfying the general formula: wherein R¹ = -halogen, -R², -OR², -CN or -CF₃; R² = -H or an alkyl group having 1-3 carbon atoms; R³ may represent the same groups as R¹, but be selected independently of R¹; Q is the monomer radical attaching the mesogenic group to the main chain of the polyurethane; n is 0 or 1; m is 0 or 1; y is an integer from 0 through 3; p is an integer from 2 through 4; R⁴ = an alkyl group having 1-12 carbon atoms; x is an integer from 0 through 6; Z = -C=N-, -N=C-, -C=C-.
Claim 2
Dependent Claim
115 words
A liquid-crystalline side chain polyurethane according to claim 1, characterised in that it is obtained by polymerisation of diisocyanate with at least one diol containing a mesogenic group and satisfying the general formula: wherein R¹ = -halogen, -R², -OR², -CN or -CF₃; R² = -H or an alkyl group having 1-3 carbon atoms; R³ may represent the same groups as R¹, but be selected independently of R¹; n is 0 or 1; m is 0 or 1; y is an integer from 0 through 3; p is an integer from 2 through 4; R⁴ = an alkyl group having 1-12 carbon atoms; x is an integer from 0 through 6; Z = -C=N-, -N=C-, -C=C-.
Claim 3
Dependent Claim
89 words
A liquid-crystalline side chain polyurethane according to claim 2, characterised in that the diol satisfies the formula: wherein R¹ = -halogen, -R², -OR², -CN or -CF₃; R² = -H or an alkyl group having 1-3 carbon atoms; R³ may represent the same groups as R¹, but be selected independently of R¹; n is 0 or 1; y is an integer from 0 through 3; p is an integer from 2 through 4; R⁴ = an alkyl group having 3-12 carbon atoms; x is an integer from 0 through 6.
Claim 4
Dependent Claim
98 words
A liquid-crystalline side chain polyurethane according to claim 2, characterised in that the diol satisfies the formula: wherein R¹ = -halogen, -R², -OR², -CN or -CF₃; R² = -H or an alkyl group having 1-3 carbon atoms; R³ may represent the same groups as R¹, but be selected independently of R¹; n is 0 or 1; y is an integer from 0 through 3; p is an integer from 2 through 4; R⁴ = an alkyl group having 4-12 carbon atoms if n=1; R⁴ = an alkyl group having 5-12 carbon atoms if n=0; X = -C=N-, -N=C-.
Claim 5
Dependent Claim
94 words
A liquid-crystalline side chain polyurethane according to claim 2, characterised in that the diol satisfies the formula: wherein R¹ = -halogen, -R², OR², -CN or -CF₃; R² = -H or an alkyl group having 1-3 carbon atoms; R³ may represent the same groups as R¹, but be selected independently of R¹; n is 0 or 1; y is an integer from 0 through 3; p is an integer from 2 through 4; R⁴ = an alkyl group having 4-12 carbon atoms if n=1; R⁴ = an alkyl group having 5-12 carbon atoms if n=0;
Claim 6
Dependent Claim
31 words
A liquid-crystalline side chain polyurethane according to any one of claims 2-5, characterised in that the diisocyanate comprises hexamethylene diisocyanate, paraphenylene diisocyanate, xylylene diisocyanate, cyclohexyl diisocyanate or a mixture of these.
Claim 7
Dependent Claim
23 words
A liquid-crystalline polyurethane composition, characterised in that this composition comprises a polyurethane according to any one of claims 1-6 and infra-red absorbing dye.
Claim 8
Dependent Claim
22 words
A liquid-crystalline polyurethane according to any one of claims 1-6, characterised in that infra-red absorbing dye is covalently incorporated into the polyurethane.
Claim 9
Dependent Claim
22 words
A liquid-crystalline polyurethane composition according to claim 7, characterised in that the infra-red absorbing dye is a squarilium or a croconium dye.
Claim 10
Dependent Claim
20 words
A liquid-crystalline polyurethane according to claim 8, characterised in that the infra-red absorbing dye is a squarilium or croconium dye.
Claim 11
Dependent Claim
17 words
A polymeric film comprising a polyurethane or polyurethane composition according to any one of the preceding claims.
Claim 12
Independent Claim
38 words
A device for optical data storage comprising a solid-state laser and a liquid-crystalline storage medium, characterised in that the liquid-crystalline storage medium is a liquid-crystalline polyurethane or liquid-crystalline polyurethane composition according to any one of preceding claims 1-10.
Claim 13
Independent Claim
28 words
A method for adjusting Tgs of liquid-crystalline polyurethanes, characterised in that a combination of non-flexible and flexible diisocyanates is used and the ratio of non-flexible/flexible diisocyanates is varied.
Claim 14
Independent Claim
40 words
A method for adjusting Tcs of liquid crystalline polyurethanes, characterised in that a blend of diols with long pending alkyl chains and diols with short pending alkyl chains is used and the ratio of said types of diols is varied.
References Cited (Backward Citations)
No citation records indexed.
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