US4428983A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the production of microcapsules
Assignee: Bayer AG
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Filing: 1981-10-13
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Granted: 1984-01-31
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Expires: 2001-10-13
Abstract
Abstract A process for encapsulating products in a polymer by interfacial polymerization, in which a stabilized dispersion of droplets of a first liquid which is to be encapsulated or a stabilized dispersion of solid particles which are to be encapsulated is formed in a continuous phase of a second liquid, and wherein one of the two capsule wall-forming reaction components is present in free form while the other of the two capsule wall-forming reaction components is present in reversibly blocked form, both reaction components are present in the first or second liquid without reacting with one another and the reaction component which is present in reversibly blocked form is deblocked by means of water present in the second or first liquid and then reacts with the reaction component present in free form to form a polymeric capsule wall, the droplets of the first liquid or the solid particles being encapsulated in small capsules consisting of polymeric material.
Inventors
- 👤 Ulrich Nehen
- 👤 Manfred Hajek
- 👤 Norbert Weimann
- 👤 Manfred Dahm
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 08:00
CPC Classifications
B; B01; B01J; B01J13/00; B01J13/02; B01J13/06; B01J13/14; B01J13/16; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2982; Y10T428/2984; Y10T428/2985; Y10T428/2989
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
190 words
A process for encapsulating products in a polymer by interfacial polymerization, in which a stabilized dispersion of droplets of a first liquid which is to be encapsulated or a stabilized dispersion of solid particles which are to be encapsulated is formed in a continuous phase of a second liquid, and wherein one of the two capsule wall-forming reaction components is present in free form and contains at least two isocyanate groups while the other of the two capsule wall-forming reaction components is present in reversibly blocked form and contains at least two reversibly blocked functional groups which are deblocked by water and contain at least two NH groups or one NH-group and one OH-group, both reaction components are present in the first or second liquid without reacting with one another and the reaction component which is present in reversibly blocked form is deblocked by means of water present in the second or first liquid and then reacts with the reaction component present in free form to form a polymeric capsule wall, the droplets of the first liquid or the solid particles being encapsulated in small capsules consisting of polymeric material.
Claim 2
Dependent Claim
190 words
A process for encapsulating products in a polymer by interfacial polymerization, in which a stabilized dispersion of droplets of a first liquid which is to be encapsulated or a stabilized dispersion of solid particles which are to be encapsulated is formed in a continuous phase of a second liquid, and wherein one of the two capsule wall-forming reaction components is present in free form and contains at least two isocyanate groups while the other of the two capsule wall-forming reaction components is present in reversibly blocked form and contains at least two reversibly blocked functional groups which are deblocked by water and contain at least two NH groups or one NH-group and one OH-group, both reaction components are present in the first or second liquid without reacting with one another and the reaction component which is present in reversibly blocked form is deblocked by means of water present in the second or first liquid and then reacts with the reaction component present in free form to form a polymeric capsule wall, the droplets of the first liquid or the solid particles being encapsulated in small capsules consisting of polymeric material.
Claim 3
Dependent Claim
38 words
A process as claimed in claim 1, characterised in that an organic liquid is used as the first liquid and an aqueous liquid is used as the second liquid, the organic liquid being insoluble in the aqueous liquid.
Claim 4
Dependent Claim
38 words
A process as claimed in claim 1, characterised in that an aqueous liquid is used as the first liquid and an organic liquid is used as the second liquid, the aqueous liquid being insoluble in the organic liquid.
Claim 5
Dependent Claim
34 words
A process as claimed in claim 1, characterised in that the reaction components present in reversibly blocked form are blocked polyamines or hydroxyamines which are converted into the free polyamines or hydroxyamines by water.
Claim 6
Dependent Claim
31 words
A process as claimed in claim 1, characterised in that the aqueous liquid additionally contains capsule wall-forming reaction components which contain at least two NH-groups or one NH-group and one OH-group.
Claim 7
Dependent Claim
21 words
A process as claimed in claim 5, characterised in that the capsule wall-forming reaction components additionally used are polyamines and/or hydroxyamines.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-01-30 | 1987-08-01 | 1988-01-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-01-30 | 1991-08-01 | 1992-01-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-01-30 | 1995-08-01 | 1996-01-31 | $7700.00 | Window Closed / Lapsed |