US4547429A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Encapsulated salts of acid particles wherein the salt particles are surrounded by a polyurethane/polyurea casing
Assignee: Sanofi Aventis Deutschland GmbH
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Filing: 1984-09-06
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Granted: 1985-10-15
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Expires: 2004-09-06
Abstract
Abstract Encapsulated salts of organic or inorganic acid particles having sparing solubility in water wherein the salt particles are surrounded by a pressure-resistant, elastic, abrasion-resistant polyurethane/polyurea casing, the ratio by weight of salt to the polyurethane component of the casing material being 1:0.2 to 1:2.5, are produced by emulsifying a mixture of 83 to 28% by weight of the salt to be encapsulated and 17 to 72% by weight of a polyurethane prepolymer containing free isocyanate groups in water in the presence of a protective colloid and reacting the emulsified prepolymer with the equivalent amount of polyamine at temperatures from 0° to 80° C., with vigorous mixing.
Inventors
- 👤 Ulrich Greiner
- 👤 Karl-Heinz Keil
- 👤 Rudolf Heinrich
- 👤 Konrad Albrecht
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 16:57
CPC Classifications
B; B01; B01J; B01J13/00; B01J13/02; B01J13/06; B01J13/14; B01J13/16; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2982; Y10T428/2989; Y10T428/2991; Y10T428/2998
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
49 words
Encapsulated particles of hydrofluoric acid salts, hydrofluoric acid complexes or hydrocyanic acid salts having sparing solubility in water wherein the particles are surrounded by a pressure-resistant, elastic, abrasion resistant polyurethane/polyurea casing, the ratio by weight of particles to the polyurethane component of the casing material being 1:0.2 to 1:2.5.
Claim 2
Dependent Claim
49 words
Encapsulated particles of hydrofluoric acid salts, hydrofluoric acid complexes or hydrocyanic acid salts having sparing solubility in water wherein the particles are surrounded by a pressure-resistant, elastic, abrasion resistant polyurethane/polyurea casing, the ratio by weight of particles to the polyurethane component of the casing material being 1:0.2 to 1:2.5.
Claim 3
Dependent Claim
37 words
Encapsulated salts according to claim 1 wherein the polyurethane/polyurea casing is the reaction product of a polyurethane prepolymer containing 20 to 70 mole % of free isocyanate groups and 10-100% of the equivalent amount of a polyamine.
Claim 4
Dependent Claim
37 words
Encapsulated salts according to claim 1 wherein the polyurethane/polyurea casing is the reaction product of a polyurethane prepolymer containing 35 to 60 mole % of free isocyanate groups with 10-100% of the equivalent amount of a polyamine.
Claim 5
Dependent Claim
14 words
Encapsulated salts according to claim 1 comprising hydrofluoric acid salts of hydrofluoric acid complexes.
Claim 6
Dependent Claim
10 words
Encapsulated salts according to claim 1 comprising hydrocyanic acid salts.
Claim 7
Dependent Claim
28 words
In the process of frosting glass by contacting glass with hydrofluoric acid, the improvement comprises the encapsulated salt of claim 4 being the source of the hydrofluoric acid.
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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) | 1988-10-14 | 1989-04-15 | 1989-10-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-10-14 | 1993-04-15 | 1993-10-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-10-14 | 1997-04-15 | 1997-10-15 | $7700.00 | Window Closed / Lapsed |