Patent US4423091A successfully refreshed from Google Patents.
US4423091A
Expired / Lapsed
US
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Method of making microcapsules
Assignee: Kanzaki Paper Manufacturing Co Ltd
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Filing: 1981-12-07
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Granted: 1983-12-27
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Expires: 2001-12-07
Abstract
Abstract The method of making microcapsules comprises performing polycondensation for producing aminoaldehyde resin in an aqueous dispersion including particles of hydrophobic core material in the presence of cation-modified polyvinyl alcohol to form aminoaldehyde resin microcapsules walls around said particles of hydrophobic core material.
Inventors
- 👤 Hiroshi Iwasaki
- 👤 Shinsuke Irii
- 👤 Haruo Omura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 17:36
CPC Classifications
B; B01; B01J; B01J13/00; B01J13/02; B01J13/06; B01J13/14; B01J13/18; B41; B41M; B41M5/00; B41M5/124; B41M5/165; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2982; Y10T428/2984; Y10T428/2985; Y10T428/2989
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
68 words
A method of making microcapsules comprising performing polycondensation for producing aminoaldehyde resin in an aqueous dispersion including particles of hydrophobic core material in the presence of cation-modified polyvinyl alcohol to form aminoaldehyde resin microcapsule walls around said particles of hydrophobic core material, said cation-modified polyvinyl alcohol present in an amount of 0.1 to 20% by weight of said aqueous dispersion and in the form of an aqueous solution.
Claim 2
Independent Claim
68 words
A method of making microcapsules comprising performing polycondensation for producing aminoaldehyde resin in an aqueous dispersion including particles of hydrophobic core material in the presence of cation-modified polyvinyl alcohol to form aminoaldehyde resin microcapsule walls around said particles of hydrophobic core material, said cation-modified polyvinyl alcohol present in an amount of 0.1 to 20% by weight of said aqueous dispersion and in the form of an aqueous solution.
Claim 3
Dependent Claim
29 words
A method of making microcapsules according to claim 1 in which said cation-modified polyvinyl alcohol has cationic radicals at 0.05 to 30 mol. % of its total monomer units.
Claim 4
Dependent Claim
29 words
A method of making microcapsules according to claim 2 in which said cation-modified polyvinyl alcohol has cationic radicals at 0.2 to 10 mol. % of its total monomer units.
Claim 5
Dependent Claim
29 words
A method of making microcapsules according to claim 1 in which said cation-modified polyvinyl alcohol has hydrophobic radicals at 0.2 to 10 mol. % of its total monomer units.
Claim 6
Dependent Claim
27 words
A method of making microcapsules according to claim 1 in which aminoaldehyde resin is produced by polycondensation of at least one amine and at least one aldehyde.
Claim 7
Dependent Claim
42 words
A method of making microcapsules according to claim 1 in which aminoaldehyde resin is produced by the steps of preparing an aldehyde resin prepolymer of at least one amine and at least one aldehyde and performing polycondensation of said aminoaldehyde resin prepolymer.
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) | 1986-12-26 | 1987-06-27 | 1987-12-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-12-26 | 1991-06-27 | 1991-12-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-12-26 | 1995-06-27 | 1995-12-27 | $7700.00 | Window Closed / Lapsed |