Patent US4524199A successfully refreshed from Google Patents.
US4524199A
Expired / Lapsed
US
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Stable polymeric dispersion and methods for making
Assignee: Xerox Corp
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Filing: 1983-11-09
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Granted: 1985-06-18
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Expires: 2003-11-09
Abstract
Abstract Dry monodispersed polymeric particles, a stabilized dispersion of such and a method for making are described. The dispersion comprises a polar dispersion medium having dispersed therein monodispersed particles comprising a thermoplastic resin core substantially insoluble in the dispersion medium formed from a styrene or butylmethacrylate containing monomer or mixtures thereof and having irreversibly anchored thereto, a nonionic amphipathic steric stabilizer comprising a graft copolymer having a portion formed from a styrene or butylmethacrylate containing monomer or mixture thereof and a portion formed from hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxybutyl methyl cellulose, hydroxypropyl methyl cellulose, ethyl cellulose or cellulose propionate. The stable dispersion is made by dissolving the nonionic cellulose ether in the polar dispersion medium and in the presence of a free radical initiator adding styrene or butylmethacrylate containing monomer a mixture thereof thereto, and permitting polymerization to take place.
Inventors
- 👤 Kar P. Lok
- 👤 Christopher K. Ober
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 20:04
CPC Classifications
C; C08; C08F; C08F251/00; C08F251/02
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
83 words
A stable dispersion comprising a nonionic polar dispersion medium having dispersed therein monodispersed particles comprising a thermoplastic resin core substantially insoluble in said dispersion medium formed from a styrene or butylmethacrylate containing monomer or mixtures thereof having irreversibly anchored thereto a nonionic amphipathic steric stabilizer comprising a graft copolymer having a portion formed from a styrene or butylmethacrylate containing monomer or mixtures thereof and a portion formed from hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxybutyl methyl cellulose, hydroxypropyl methyl cellulose, ethyl cellulose or cellulose propionate.
Claim 2
Dependent Claim
83 words
A stable dispersion comprising a nonionic polar dispersion medium having dispersed therein monodispersed particles comprising a thermoplastic resin core substantially insoluble in said dispersion medium formed from a styrene or butylmethacrylate containing monomer or mixtures thereof having irreversibly anchored thereto a nonionic amphipathic steric stabilizer comprising a graft copolymer having a portion formed from a styrene or butylmethacrylate containing monomer or mixtures thereof and a portion formed from hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxybutyl methyl cellulose, hydroxypropyl methyl cellulose, ethyl cellulose or cellulose propionate.
Claim 3
Dependent Claim
24 words
The stable dispersion of claim 1, wherein said monodispersed particles have a size within the range from about 0.3 microns to about 15 microns.
Claim 4
Dependent Claim
24 words
The stable dispersion of claim 2, wherein said monodispersed particles have a size within the range from about 8 microns to about 10 microns.
Claim 5
Dependent Claim
13 words
The stable dispersion of claim 1, wherein said monodispersed particles are substantially spherical.
Claim 6
Dependent Claim
18 words
The stable dispersion of claim 1, wherein said polar dispersion medium is a mixture of water and alcohol.
Claim 7
Dependent Claim
29 words
The stable dispersion of claim 1, wherein said thermoplastic resin core comprises polystyrene and said nonionic amphipathic steric stabilizer comprises a graft copolymer of polystyrene grafted with hydroxypropyl cellulose.
Claim 8
Dependent Claim
42 words
The stable dispersion of claim 1, wherein said thermoplastic resin core has a weight average molecular weight from about 10,000 to about 250,000, and said nonionic amphipathic steric stabilizer has a weight average molecular weight of from about 10,000 to about 1,000,000.
Claim 9
Dependent Claim
28 words
The stable dispersion of claim 1, wherein said amphipathic steric stabilizer comprises a hairy like graft copolymer irreversibly anchored to the core and solvated by the dispersion medium.
Claim 10
Dependent Claim
20 words
The stable dispersion of claim 1 wherein the colloidal stability is maintained in the presence of charged and uncharged additives.
Claim 11
Dependent Claim
72 words
Dry redispersable nonionic polymeric particles comprising a thermoplastic resin core formed from a styrene or butylmethacrylate containing monomer or mixtures thereof having irreversibily anchored thereto a sheath of a nonionic amphipathic steric stabilizer comprising a graft copolymer having a portion formed from a styrene or butylmethacrylate containing monomer or mixtures thereof and a portion formed from hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxy butyl methyl cellulose, hydroxypropyl methyl cellulose, ethyl cellulose or cellulose propionate.
Claim 12
Dependent Claim
72 words
Dry redispersable nonionic polymeric particles comprising a thermoplastic resin core formed from a styrene or butylmethacrylate containing monomer or mixtures thereof having irreversibily anchored thereto a sheath of a nonionic amphipathic steric stabilizer comprising a graft copolymer having a portion formed from a styrene or butylmethacrylate containing monomer or mixtures thereof and a portion formed from hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxy butyl methyl cellulose, hydroxypropyl methyl cellulose, ethyl cellulose or cellulose propionate.
Claim 13
Dependent Claim
25 words
The dry particles of claim 10, wherein said monodispersed particles have a size within the range of from about 0.3 microns to about 15 microns.
Claim 14
Dependent Claim
24 words
The dry particles of claim 11, wherein said monodispersed particles have a size within the range from about 8 microns to about 10 microns.
Claim 15
Dependent Claim
13 words
The dry particles of claim 10, wherein said monodispersed particles are substantially spherical.
Claim 16
Dependent Claim
29 words
The dry particles of claim 10, wherein said thermoplastic resin core comprises polystyrene and said nonionic amphipathic steric stabilizer comprises a graft copolymer of polystyrene grafted with hydroxypropyl cellulose.
Claim 17
Dependent Claim
42 words
The dry particles of claim 10, wherein said thermoplastic resin core has a number average molecular weight from about 10,000 to about 250,000, and said nonionic amphipathic steric stabilizer has a weight average molecular weight of from about 10,000 to about 1,000,000.
Claim 18
Independent Claim
130 words
The method of making a nonionic stable dispersion of polymer particles comprising dissolving a nonionic material comprising hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxy butyl methyl cellulose, hydroxypropyl methyl cellulose, ethyl cellulose or cellulose propionate in a polar dispersion medium in the presence of a free radical initiator, adding a styrene or butylmethacrylate containing monomer or mixture thereof to said dispersion medium, said monomer being soluble in said dispersion medium, polymerizing said monomer in situ to form a dispersion of particles comprising a polymer core having irreversibly anchored thereto a nonionic amphipathic steric stabilizer comprising a graft copolymer having a portion formed from said hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxy butyl methyl cellulose or hydroxypropyl methyl cellulose, ethyl cellulose or cellulose propionate and a portion formed from said styrene or butylmethacrylate containing monomer.
Claim 19
Independent Claim
130 words
The method of making a nonionic stable dispersion of polymer particles comprising dissolving a nonionic material comprising hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxy butyl methyl cellulose, hydroxypropyl methyl cellulose, ethyl cellulose or cellulose propionate in a polar dispersion medium in the presence of a free radical initiator, adding a styrene or butylmethacrylate containing monomer or mixture thereof to said dispersion medium, said monomer being soluble in said dispersion medium, polymerizing said monomer in situ to form a dispersion of particles comprising a polymer core having irreversibly anchored thereto a nonionic amphipathic steric stabilizer comprising a graft copolymer having a portion formed from said hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxy butyl methyl cellulose or hydroxypropyl methyl cellulose, ethyl cellulose or cellulose propionate and a portion formed from said styrene or butylmethacrylate containing monomer.
Claim 20
Dependent Claim
23 words
The method of making a stable dispersion according to claim 16, wherein said monomer is styrene and said nonionic material is hydroxypropyl cellulose.
Claim 21
Dependent Claim
39 words
The method of making a stable dispersion according to claim 17, wherein said styrene is present in an amount greater than about 15% by volume and said polymerization takes place at a temperature in excess of about 50° C.
Claim 22
Dependent Claim
24 words
The method of making a stable dispersion according to claim 16, wherein said polar dispersion medium is a mixture of water, alcohol or ether.
Claim 23
Dependent Claim
21 words
The method of making a stable dispersion according to claim 16, wherein said polymerization process provides substantially spherical monodispersed polymer particles.
Claim 24
Dependent Claim
29 words
The method of making a stable dispersion according to claim 20, wherein said monodispersed particles have a size within the range from about 8 microns to about 10 microns.
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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) | 1988-06-17 | 1988-12-17 | 1989-06-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-06-17 | 1992-12-17 | 1993-06-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-06-17 | 1996-12-17 | 1997-06-18 | $7700.00 | Window Closed / Lapsed |