Patent DE2402829A1 successfully refreshed from Google Patents.
US3872050A
Expired / Lapsed
US
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Polyurethane liquid crystal dispersion system and devices
Assignee: BELL JAMES R MR JR
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Filing: 1973-08-09
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Granted: 1975-03-18
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Expires: 1993-08-09
Abstract
Abstract Liquid crystal materials, particularly cholesteric liquid crystal materials, are protected against dust, contamination and the like by being dispersed as discrete naked aggregates in polyurethane materials. The liquid crystal material is mixed with polyurethane-elastomer or polyurethane polymers and thereafter polymerization or drying of the mixture precursors is carried out. The liquid crystal material is uniformly dispersed in the polyurethane without experiencing chemical degradation. Films, sheets, or other three-dimensional forms of polyurethane polymer containing dispersed liquid crystals can then be used as temperature indicators, stress indicators, or for other purposes, e.g., novelty items and toys. In certain installations the iridescence of the product achieves useful aesthetic properties.
Inventors
- 👤 William J Benton
- 👤 Joseph R Quigley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 00:50
CPC Classifications
G; G01; G01K; G01K11/00; G01K11/12; G01K11/16; G01K11/165; C; C08; C08K; C08K5/00; C08K5/0008; C08K5/02; C08K5/04; C08K5/10; C09; C09D; C09D5/00; C09D5/26; C09K; C09K19/00; C09K19/52; C09K19/54; C09K19/542; C09K19/544; G01B; G01B11/00; G01B11/16; G01B11/165
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
82 words
A POLYMERIZED POLYURETHANE ELASTOMER WHICH IS A REACTION PRODUCT OF AT LEAST ONE ORGANIC POLYISOCYANATE AND AT LEAST ONE ORGANIC COMPOUND CONTAINING AT LEAST ONE ACTIVE HYDROGEN ACCORDING TO THE ZEREWITINOFF METHOD. SAID ELASTOMER HAVING UNIFORMLY DISPERSED THERETHROUGH NAKED AGGREGATES OF LIQUID CRYSTALS WHICH PROVIDE A VISIBLE RESPONSE TO APPLICATION OF ENERGY SAID LIQUID CRYSTALS HAVING A PARTICLE SIZE OF 0.1 TO 300 MICRONS AND WHEREIN THE SAID LIQUID CRYSTALS CONSTITUTE AT LEAST 20 PER CENT OF THE WEIGHT OF THE ELASTOMER.
Claim 2
Dependent Claim
82 words
A POLYMERIZED POLYURETHANE ELASTOMER WHICH IS A REACTION PRODUCT OF AT LEAST ONE ORGANIC POLYISOCYANATE AND AT LEAST ONE ORGANIC COMPOUND CONTAINING AT LEAST ONE ACTIVE HYDROGEN ACCORDING TO THE ZEREWITINOFF METHOD. SAID ELASTOMER HAVING UNIFORMLY DISPERSED THERETHROUGH NAKED AGGREGATES OF LIQUID CRYSTALS WHICH PROVIDE A VISIBLE RESPONSE TO APPLICATION OF ENERGY SAID LIQUID CRYSTALS HAVING A PARTICLE SIZE OF 0.1 TO 300 MICRONS AND WHEREIN THE SAID LIQUID CRYSTALS CONSTITUTE AT LEAST 20 PER CENT OF THE WEIGHT OF THE ELASTOMER.
Claim 3
Dependent Claim
16 words
A film comprising the elastomer of claim 1 having a thickness of 0.5 to 20 mils.
Claim 4
Dependent Claim
17 words
The elastomer of claim 1 wherein the said liquid crystals comprise at least one cholesteric liquid crystal.
Claim 5
Dependent Claim
28 words
The elastomer of claim 3 wherein the said liquid crystal is temperature stabilized and provides a first visible indication when stretched and a second visible indication when compressed.
Claim 6
Dependent Claim
24 words
A cast article comprising the elastomer of claim 4 which exhibits a first color change when stretched and a second color chanbe when compressed.
Claim 7
Dependent Claim
24 words
The polymerized polyurethane of claim 1 wherein the said liquid crystals contain 0.5 to 5 percent by weight of at least one dark dye.
Claim 8
Dependent Claim
23 words
The polymerized polyurethane elastomer of claim 1 wherein the said naked aggregates contain 1 to 5 percent of an ultraviolet radiation absorber. 31
Claim 9
Dependent Claim
17 words
The elastomer of claim 3 wherein the said liquid crystal is temperature insensitive at temperatures below 100*F.
Claim 10
Dependent Claim
58 words
A coating composition comprising a mixture of thermoplastic polyurethane polymer in a volatile non-aqueous solvent, said composition containing a dispersion of naked aggregates of liquid crystals having a particle size of 0.1 to 300 microns which provide visible response to the application of energy, the weight ratio of said liquid crystals to said polymer being at least 0.3.
Claim 11
Dependent Claim
58 words
A coating composition comprising a mixture of thermoplastic polyurethane polymer in a volatile non-aqueous solvent, said composition containing a dispersion of naked aggregates of liquid crystals having a particle size of 0.1 to 300 microns which provide visible response to the application of energy, the weight ratio of said liquid crystals to said polymer being at least 0.3.
Claim 12
Dependent Claim
18 words
The coating composition of claim 9 wherein the said liquid crystals comprise at least one cholesteric liquid crystal.
Claim 13
Dependent Claim
63 words
An elastic article formed from a polymerized polyurethane elastomer having a modulus of elasticity less than 5,000 psi and containing at least 20 percent by weight of a cholesteric liquid crystal dispersed as naked aggregates, having a particle size of 0.1 to 300 microns said article exhibiting transitory color changes towards shroter wave lengths when stretched and towards longer wave lengths when compressed.
Claim 14
Dependent Claim
63 words
An elastic article formed from a polymerized polyurethane elastomer having a modulus of elasticity less than 5,000 psi and containing at least 20 percent by weight of a cholesteric liquid crystal dispersed as naked aggregates, having a particle size of 0.1 to 300 microns said article exhibiting transitory color changes towards shroter wave lengths when stretched and towards longer wave lengths when compressed.
Claim 15
Dependent Claim
44 words
A temperature indicating device having a supporting substrate and a coating over at least one portion of its surface, said coating being formed from the composition of claim 1 and having a liquid crystal ingredient which exhibits a visible response at a preselected temperature.
Claim 16
Dependent Claim
22 words
The elastomer of claim 1 wherein the said naked aggregates have a particle size in the range of 0.5 to 50 microns.
Claim 17
Dependent Claim
12 words
A film as defined in claim 2 which is elastic and self-supporting.
Claim 18
Dependent Claim
36 words
A temperature indicating device including a dark colored area on the surface of a body whose temperature is to be indicated and a film as defined in claim 2 applied over the said dark colored area.
Claim 19
Independent Claim
104 words
A method for preparing a polyurethane elastomer which comprises combining in a single mixture A. organic polyisocyanate; B. a co-reactive compound having at least one active hydrogen by the Zerewitinoff method; C. liquid crystals which provide a visible response to the application of energy, said liqUid crystals comprising at least 30 percent by weight of said mixture; dispersing the said liquid crystals in naked aggregates having a particle size from 0.1 to 300 microns uniformly throughout the said mixture; casting the said mixture into a selected shape; and curing the said mixture at a temperature below the degradation temperature of the said liquid crystals.
Claim 20
Independent Claim
104 words
A method for preparing a polyurethane elastomer which comprises combining in a single mixture A. organic polyisocyanate; B. a co-reactive compound having at least one active hydrogen by the Zerewitinoff method; C. liquid crystals which provide a visible response to the application of energy, said liqUid crystals comprising at least 30 percent by weight of said mixture; dispersing the said liquid crystals in naked aggregates having a particle size from 0.1 to 300 microns uniformly throughout the said mixture; casting the said mixture into a selected shape; and curing the said mixture at a temperature below the degradation temperature of the said liquid crystals.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-03-17 | 1978-09-16 | 1979-03-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-17 | 1982-09-16 | 1983-03-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-17 | 1986-09-16 | 1987-03-18 | $7700.00 | Window Closed / Lapsed |