US3965022A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pressure-fixable developing powder
Assignee: 3M Co
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Filing: 1973-06-29
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Granted: 1976-06-22
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Expires: 1993-06-29
Abstract
Abstract A dry, pressure-fixable, developing powder comprising a thermoplastic component having a low creep compliance and a non-volatile component having a high creep compliance, wherein the low creep compliance material is present in a greater amount by volume than the other component.
Inventors
- 👤 Doyle L. Strong
- 👤 Curtis Dale Hargadine
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 14:06
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/087; G03G9/08775; G03G15/00; G03G15/20; G03G15/2092; G03G9/08702; G03G9/08706; G03G9/08708; G03G9/08711; G03G9/08726; G03G9/08728; G03G9/08737; G03G9/08742; G03G9/08764; G03G9/08777; G03G9/08779; G03G9/08784; G03G9/08788; G03G9/08797; Y; Y10; Y10S; Y10S430/00; Y10S430/001; Y10S430/104
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
177 words
Flowable, pressure-fixable, dry powder particles, the binder material of said particles having a conductivity of at most 10 - 12 mho/cm., said binder comprising (a) about 74 to 98 parts by volume of a thermoplastic component having a softening point of at least about 60°C., a 10-second shear creep compliance in the range of about 1 × 10 - 12 cm 2 /dyne to 1 × 10 - 10 cm 2 /dyne, and a heat deflection temperature below about 300°C., and (b) about 2 to 26 parts by volume of a non-volatile component having a principal glass transition temperature below about 0° C. and a 10-second shear creep compliance greater than about 8 × 10 - 8 cm 2 /dyne; wherein said powder exhibits a transfer density of less than about 0.15 and a paper abrasion density of less than about 0.15; wherein said non-volatile component is an elastomer selected from the group consisting of synthetic diene rubbers, acrylate rubbers, polyurethane elastomers, and rubbery block copolymers; and wherein said binder further comprises a tackifier for said elastomer.
Claim 2
Dependent Claim
177 words
Flowable, pressure-fixable, dry powder particles, the binder material of said particles having a conductivity of at most 10 - 12 mho/cm., said binder comprising (a) about 74 to 98 parts by volume of a thermoplastic component having a softening point of at least about 60°C., a 10-second shear creep compliance in the range of about 1 × 10 - 12 cm 2 /dyne to 1 × 10 - 10 cm 2 /dyne, and a heat deflection temperature below about 300°C., and (b) about 2 to 26 parts by volume of a non-volatile component having a principal glass transition temperature below about 0° C. and a 10-second shear creep compliance greater than about 8 × 10 - 8 cm 2 /dyne; wherein said powder exhibits a transfer density of less than about 0.15 and a paper abrasion density of less than about 0.15; wherein said non-volatile component is an elastomer selected from the group consisting of synthetic diene rubbers, acrylate rubbers, polyurethane elastomers, and rubbery block copolymers; and wherein said binder further comprises a tackifier for said elastomer.
Claim 3
Dependent Claim
23 words
A powder in accordance with claim 1 wherein said thermoplastic component is selected from the group consisting of polystyrenes, coumarone-indene resins, and polyterpenes.
Claim 4
Dependent Claim
17 words
A powder in accordance with claim 1 wherein electrically conductive particles are firmly anchored in said binder.
Claim 5
Dependent Claim
112 words
A powder in accordance with claim 5 wherein said electrically conductive particles have a conductivity of at least 10 - 2 mho/cm and an average diameter below about 100 millimicrons; and wherein said dry powder particles exhibit: a. an electronic conductivity ranging monatonically without decreasing from between about 10 - 11 and 10 - 4 mho/cm in a 100 v./cm. DC electrical field to between about 10 - 8 and 10 - 3 mho/cm in a 10,000 v./cm. DC electrical field, b. a number average particles diameter below about 20 microns, and c. a volume ratio of said electrically conductive particles to total dry powders particle volume of between 0.01/100 and 4/100.
Claim 6
Dependent Claim
26 words
A powder in accordance with claim 4 wherein said electrically conductive particles of highly conductive carbon having a conductivity of at least 10 - 2 mho/cm.
Claim 7
Dependent Claim
17 words
A powder in accordance with claim 3 wherein said dry powder particles further contain their magnetizable particles.
Claim 8
Dependent Claim
13 words
A powder in accordance with claim 6 wherein said magnetizable particles comprise magnetite.
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) | 1979-06-22 | 1979-12-22 | 1980-06-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-06-22 | 1983-12-22 | 1984-06-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-06-22 | 1987-12-22 | 1988-06-22 | $7700.00 | Window Closed / Lapsed |