US4960669A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing toner by generating non-soluble cationic inorganic particles in dispersant medium
Assignee: Canon Inc
•
Filing: 1988-12-02
•
Granted: 1990-10-02
•
Expires: 2008-12-02
Abstract
Abstract Toner for developing electrostatic latent images is produced by dispersing an anionic inorganic dispersant in an aqueous medium; generating cationic inorganic particles in the aqueous medium which are hard to dissolve in water so as to produce a dispersant medium of the anionic inorganic dispersant and the cationic inorganic particles; dispersing a monomer composition including at least polymerizable monomer and a cationic material into the dispersant medium and generate particles of the monomer composition; and suspension-polymerizing the monomer composition particles and produce toner.
Inventors
- 👤 Hiromi Mori
- 👤 Reiko Morimoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 03:59
CPC Classifications
C; C08; C08F; C08F2/00; C08F2/44; G; G03; G03G; G03G9/00; G03G9/08; G03G9/087; G03G9/08702
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
117 words
A process for producing toner for developing electrostatic latent images, comprising the steps of: dispersing an anionic inorganic dispersant in an aqueous phase; generating cationic inorganic particles comprising metal hydroxides in said aqueous phase from a water-soluble compound with stirring in order to produce a dispersant medium in which said anionic inorganic dispersant and said cationic inorganic particles coexist, said cationic inorganic particles having a solubility of at most 0.1 g in 100 g of 25° C. water; dispersing a monomer composition comprising a polymerizable vinyl monomer and a cationic material into said dispersant medium such that particles of said monomer composition are generated; and suspension polymerizing said monomer composition particles in order to produce said toner.
Claim 2
Dependent Claim
117 words
A process for producing toner for developing electrostatic latent images, comprising the steps of: dispersing an anionic inorganic dispersant in an aqueous phase; generating cationic inorganic particles comprising metal hydroxides in said aqueous phase from a water-soluble compound with stirring in order to produce a dispersant medium in which said anionic inorganic dispersant and said cationic inorganic particles coexist, said cationic inorganic particles having a solubility of at most 0.1 g in 100 g of 25° C. water; dispersing a monomer composition comprising a polymerizable vinyl monomer and a cationic material into said dispersant medium such that particles of said monomer composition are generated; and suspension polymerizing said monomer composition particles in order to produce said toner.
Claim 3
Dependent Claim
28 words
The process for producing toner of claim 1, wherein said metal hydroxide particles have a solubility of at most 0.05 g in 100 g of 25° C. water.
Claim 4
Dependent Claim
29 words
The process for producing toner of claim 1, wherein said metal hydroxides are selected from the group consisting of aluminum (III) hydroxide, iron (III) hydroxide and chromium (III) hydroxide.
Claim 5
Dependent Claim
22 words
The process for producing toner of claim 3, wherein said metal hydroxides have a particle size ranging from 5 to 200 microns.
Claim 6
Dependent Claim
16 words
The process for producing toner of claim 3, wherein said metal hydroxide is aluminum (III) hydroxide.
Claim 7
Dependent Claim
25 words
The process for producing toner of claim 5, wherein said aluminum (III) hydroxide is prepared by hydrolyzing an aluminum salt or by neutralizing sodium aluminate.
Claim 8
Dependent Claim
18 words
The process for producing toner of claim 6, wherein said aluminum salt is aluminum sulfide or aluminum chloride.
Claim 9
Dependent Claim
19 words
The process for producing toner of claim 7, wherein said aluminum salt is hydrolyzed using ammonium or sodium carbonate.
Claim 10
Dependent Claim
15 words
The process for producing toner of claim 1, wherein said anionic inorganic dispersant comprises silica.
Claim 11
Dependent Claim
34 words
The process for producing toner of any of claims 1, 2, 3 or 9, wherein said anionic inorganic dispersant and said cationic inorganic particles are used in a ratio of from 100:2 to 100:40.
Claim 12
Dependent Claim
32 words
The process for producing toner of claim 10, wherein said anionic inorganic dispersant and said cationic inorganic particles are used together from 1 to 20 parts by weight of said monomer composition.
Claim 13
Dependent Claim
28 words
The process for producing toner of claim 11, wherein said anionic inorganic dispersant and said cationic inorganic particles are used in a ratio of from 100:4 to 100:20.
Claim 14
Dependent Claim
32 words
The process for producing toner of claim 12, wherein said anionic inorganic dispersant and said cationic inorganic particles are used together from 2 to 15 parts by weight of said monomer composition.
Claim 15
Dependent Claim
32 words
The process for producing toner of any of claims 1, 2, 3, or 4, wherein said monomer composition is dispersed using a blade having a peripheral speed of 5 to 25 m/sec.
Claim 16
Dependent Claim
19 words
The process for producing toner of claim 14, wherein said monomer composition is dispersed for 5 to 60 minutes.
Claim 17
Dependent Claim
18 words
The process for producing toner of claim 15, wherein said peripheral blade speed is 15 to 25 m/sec.
Claim 18
Dependent Claim
24 words
The process for producing toner of claim 14, wherein said monomer composition has a viscosity of 50 to 10,000 cps when it is dispersed.
Claim 19
Dependent Claim
26 words
The process for producing toner of claim 17, wherein said dispersant medium has a temperature of 20 to 80° C. when said monomer composition is dispersed.
Claim 20
Dependent Claim
24 words
The process for producing toner of claim 18, wherein said monomer composition has a viscosity of 100 to 5000 cps when it is dispersed.
Claim 21
Dependent Claim
26 words
The process for producing toner of claim 19, wherein said dispersant medium has a temperature of 40° to 70° C. when said monomer composition is dispersed.
Claim 22
Dependent Claim
29 words
The process for producing toner of claim 14, wherein the dispersant medium is from 200 to 1,000 parts by weight per 100 parts by weight of said monomer composition.
Claim 23
Dependent Claim
19 words
The process for producing toner of claim 21, wherein said polymerizable monomer is substantially nonsoluble in said aqueous phase.
Claim 24
Dependent Claim
22 words
The process for producing toner of claim 21, wherein said monomer composition particles have a size of substantially 5 to 12 microns.
Claim 25
Dependent Claim
22 words
The process for producing toner of claim 22, wherein said monomer composition particles have a size of substantially 5 to 10 microns.
Claim 26
Dependent Claim
28 words
The process for producing toner of claim 1, wherein said metal hydroxide is generated in said aqueous phase from the water-soluble compound with stirring exhibiting high shearing force.
References Cited (Backward Citations)
US4345015A
Cited
GB2029425A
Cited
JPS5742052A
Cited
JPS56116044A
Cited
JPS5953856A
Cited
JPS59123852A
Cited
US4592990A
Cited
GB2133571A
Cited
JPS6057856A
Cited
JPS62266561A
Cited
US4804610A
Cited
US4816366A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-10-01 | 1994-04-02 | 1994-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-10-01 | 1998-04-02 | 1998-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-10-01 | 2002-04-02 | 2002-10-02 | $7700.00 | Window Closed / Lapsed |