US4022738A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Developing powder
Assignee: Ricoh Co Ltd
•
Filing: 1975-11-28
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Granted: 1977-05-10
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Expires: 1995-11-28
Abstract
Abstract Developing powder, called the toner, for use in developing an electrostatic latent image or a magnetic latent image, said developing powder consisting essentially of a mixture of low molecular polyolefins and alkyl-modified phenol resins, the developed image being firmly fixed to an image-forming substrate only by applying pressure to the toner image formed on the substrate.
Inventors
- 👤 Masato Shimada
- 👤 Katsuomi Kobayashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 16:29
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/087; G03G9/08702; G03G9/08704; G03G9/08742; G03G9/08746; G03G9/08748
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
101 words
In a flowable, pressure-fixable, dry powder useful as a toner for developing electrostatic latent images or magnetic latent images, said powder consisting essentially of coloring matter selected from the group consisting of pigments and dyestuffs blended with synthetic resin, the improvement which comprises: said synthetic resin consists essentially of a mixture of (A) from 5 to 95 parts by weight of a polyolefin having a molecular weight of from 1000 to 10000 and selected from the group consisting of polyethylene and polypropylene, and (B) from 5 to 95 parts by weight of alkyl (C 4 to C 17 )-modified phenol resin.
Claim 2
Dependent Claim
101 words
In a flowable, pressure-fixable, dry powder useful as a toner for developing electrostatic latent images or magnetic latent images, said powder consisting essentially of coloring matter selected from the group consisting of pigments and dyestuffs blended with synthetic resin, the improvement which comprises: said synthetic resin consists essentially of a mixture of (A) from 5 to 95 parts by weight of a polyolefin having a molecular weight of from 1000 to 10000 and selected from the group consisting of polyethylene and polypropylene, and (B) from 5 to 95 parts by weight of alkyl (C 4 to C 17 )-modified phenol resin.
Claim 3
Dependent Claim
20 words
A powder as claimed in claim 1 in which said polyolefin has a molecular weight of from 1000 to 5000.
Claim 4
Dependent Claim
13 words
A powder as claimed in claim 1 in which said polyolefin is polyethylene.
Claim 5
Dependent Claim
13 words
A powder as claimed in claim 1 in which said polyolefin is polypropylene.
Claim 6
Dependent Claim
28 words
A powder as claimed in claim 1 in which said alkyl (C 4 to C 17 )-modified phenol resin has a molecular weight of from 500 to 1000.
Claim 7
Dependent Claim
50 words
A powder as claimed in claim 5 in which said synthetic resin contains a minor amount of a resin selected from the group consisting of acrylic resin, rosin-modified phenol resin, epoxy resin, alkyl resin, phenol resin, maleic acid resin, petroleum resin, polyvinyl chloride, polyvinyl acetate, polyurethane, polystyrene and polyvinyl naphthalene.
References Cited (Backward Citations)
US3239465A
Cited
US3373127A
Cited
US3377286A
Cited
US3591503A
Cited
US3775326A
Cited
US3873325A
Cited
US3925219A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-05-09 | 1980-11-08 | 1981-05-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-05-09 | 1984-11-08 | 1985-05-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-05-09 | 1988-11-08 | 1989-05-10 | $7700.00 | Window Closed / Lapsed |