US4576890A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of encapsulated electrostatographic toner material
Assignee: Fujifilm Holdings Corp
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Filing: 1984-03-14
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Granted: 1986-03-18
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Expires: 2004-03-14
Abstract
Abstract A process for the preparation of an encapsulated electrostatographic toner material comprising a stage of forming shells around micro-droplets of core material containing colorant dispersed in an aqueous medium to produce microcapsules therein, and a stage of separating the microcapsules from the aqueous medium, which is characterized in that methylcellulose is employed for stabilizing the micro-droplets of core material in the aqueous medium.
Inventors
- 👤 Noriyuki Hosoi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 15:46
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/093; G03G9/09392; G03G9/0935; G03G9/09357; G03G9/09371
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
64 words
A process for the preparation of an encapsulated electrostatographic toner material comprising a stage of forming shells around micro-droplets of hydrophobic core material containing colorant dispersed in an aqueous medium to produce microcapsules therein, and a stage of separating the microcapsules from the aqueous medium, which is characterized in that methylcellulose is employed for stabilizing the micro-droplets of core material in the aqueous medium.
Claim 2
Dependent Claim
64 words
A process for the preparation of an encapsulated electrostatographic toner material comprising a stage of forming shells around micro-droplets of hydrophobic core material containing colorant dispersed in an aqueous medium to produce microcapsules therein, and a stage of separating the microcapsules from the aqueous medium, which is characterized in that methylcellulose is employed for stabilizing the micro-droplets of core material in the aqueous medium.
Claim 3
Dependent Claim
30 words
The process for the preparation of an encapsulated electrostatographic toner material as claimed in claim 1, in which said methylcellulose has an average molecular weight ranging from 10,000 to 50,000.
Claim 4
Dependent Claim
32 words
The process for the preparation of an encapsulated electrostatographic toner material as claimed in claim 1, in which the methylcellulose has a methoxy substitution degree in the range of 1.2 to 2.0.
Claim 5
Dependent Claim
32 words
The process for the preparation of an encapsulated electrostatographic toner material as claimed in claim 3 in which the methylcellulose is substituted with hydrooxypropoxy groups in a portion of its methoxy groups.
Claim 6
Dependent Claim
34 words
The process for the preparation of an encapsulated electrostatographic toner material as claimed in claim 4, in which 20 to 60% of the methoxy groups attached to the methylcellulose are substituted with hydroxypropoxy groups.
Claim 7
Dependent Claim
36 words
The process for the preparation of an encapsulated electrostatographic toner material as claimed in claim 1 in which said the stage of forming shells around micro-droplets of core material is performed by an interfacial polymerization method.
Claim 8
Dependent Claim
27 words
The process for the preparation of an encapsulated electrostatographic toner material as claimed in claim 1, in which said methylcellulose is made hydrophobic by treatment with methylolmelamine.
Claim 9
Dependent Claim
42 words
The process for the preparation of an encapsulated electrostatographic toner material as claimed in claim 1, in which said methylcellulose is employed in an amount of not higher than 10% by weight based on the total amount of materials constituting the microcapsules.
Claim 10
Dependent Claim
41 words
The process for the preparation of an encapsulated electrostatographic toner material as claimed in claim 6 in which said shell comprises at least one resin selected from the group consisting of a polyurethane resin, a polyurea resin and a polyamide resin.
Claim 11
Dependent Claim
47 words
The process for the preparation of an encapsulated electrostatographic toner material as claimed in claim 6 in which said shell is composed of a complex layer comprising at least two resins selected from the group consisting of a polyurethane resin, a polyurea resin and a polyamide resin.
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) | 1989-03-17 | 1989-09-16 | 1990-03-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-03-17 | 1993-09-16 | 1994-03-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-03-17 | 1997-09-16 | 1998-03-18 | $7700.00 | Window Closed / Lapsed |