US3821113A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Liquid developer for electrophotography
Assignee: Kyocera Mita Industrial Co Ltd
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Filing: 1972-10-16
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Granted: 1974-06-28
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Expires: 1992-10-16
Abstract
Abstract A liquid developer for electrophotography comprising particles of an image forming material selected from dyestuffs, pigments and powdery metals dispersed in a composite dispersion medium comprising a liquid carrier of high electric resistance and an asphalt extract which is at least substantially completely dissolvable in the liquid carrier and which is obtained by extracting an asphalt with a saturated hydrocarbon liquid, in which the image forming material particles are charged negatively by the dispersion medium, thereby giving a reverse visible image in the case of a negative electrostatic latent image or a nonreverse visible image in the case of a positive electrostatic latent image.
Inventors
- 👤 H Morikawa
- 👤 K Nagahashi
- 👤 T Aizawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 05:02
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/12; G03G9/13
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
26 words
The liquid developer of claim 1 wherein said straight chain aliphatic hydrocarbon is selected from n-pentane, n-hexane, n-heptane, n-octane, n-decane, n-undecane, n-dodecane, n-tridecane, n-hexadecane and n-octadecane.
Claim 2
Dependent Claim
39 words
The liquid developer of claim 1 wherein said branched aliphatic hydrocarbon is selected from isopentane, isohexane, 2, 2-dimethylbutane, isooctane, and C9-C12 isoparaffin mixtures (boiling point 176.7 - 186*C.), C9-C12 paraffin mixtures (boiling point 159 - 176.7*C.) and Isopar R.
Claim 3
Dependent Claim
17 words
The liquid developer of claim 1 wherein said alicyclic hydrocarbon is selected from cyclopentane, cyclohexane and methylcyclohexane.
Claim 4
Dependent Claim
41 words
The liquid developer of claim 1 wherein said straight chain aliphatic hydrocarbon contains from 5 to 16 carbon atoms, said branched chain aliphatic hydrocarbon contains from 5 to 12 carbon atoms and said alicyclic hydrocarbon contains 5 or 6 carbon atoms.
Claim 5
Dependent Claim
33 words
The liquid developer of claim 1 wherein said liquid carrier is selected from straight chain aliphatic hydrocarbons, branched chain aliphatic hydrocarbons, halogenated hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, mixed hydrocarbon liquids and dimethyl polysiloxane.
Claim 6
Dependent Claim
28 words
The liquid developer of claim 1 wherein said extract of asphalt is present in an amount of 0.5 - 3 grams per liter of said composite dispersion medium.
Claim 7
Dependent Claim
28 words
The liquid developer of claim 1 wherein said image forming material is present in an amount of 0.05 to 5 grams per liter of said composite dispersion medium.
Claim 8
Dependent Claim
29 words
The liquid developer of claim 8 wherein said image forming material is present in an amount of from 0.1 to 1.5 grams per liter of said composite dispersion medium.
Claim 9
Dependent Claim
210 words
A liquid developer for developing electrostatic latent images consisting essentially of: a. a composite dispersion medium consisting essentially of i. a liquid carrier of a dielectric constant of not more than 3 and a resistance of not less than 109 ohm-centimeter selected from straight chain aliphatic hydrocarbons, branched chain aliphatic hydrocarbons, halogenated hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, mixed hydrocarbon liquids and dimethyl polysiloxane, and ii. an extract of asphalt which is at least substantially completely dissolvable in said liquid carrier, said extract of asphalt being obtained by extracting an asphalt selected from petroleum asphalt, straight asphalt and blown asphalt with a saturated hydrocarbon liquid selected from n-pentane, n-hexane, n-octane, n-decane, n-undecane, n-dodecane, n-tridecane, n-hexadecane, n-octadecane, isohexane, 2,2-dimethylbutene, isooctane, C9-C12 isoparaffin mixture (boiling point 176.7 - 180*C.) and C9-C12 paraffin mixture (boiling 159 - 176.7*C.), cyclopentane and methylcyclohexane, and b. an image-forming material dispersed in said composite dispersion medium selected from dyestuffs, pigments and powdery metals, said image-forming material being present in an amount of 0.05 to 5 grams per liter of said composite dispersion medium, said extract of asphalt being present in an amount of 0.1 to 30 grams per liter of said composite dispersion medium, the particles of said image-forming material being negatively charged in said composite dispersion medium.
Claim 10
Dependent Claim
28 words
The liquid developer of claim 10 wherein said extract of asphalt is present in an amount of 0.5 - 3 grams per liter of said composite dispersion medium.
Claim 11
Dependent Claim
29 words
The liquid developer of claim 10 wherein said image forming material is present in an amount of from 0.1 to 1.5 grams per liter of said composite dispersion medium.
Claim 12
Dependent Claim
32 words
The liquid developer of claim 10 wherein the extraction of said asphalt is carried out by using 5 to 1000 parts of said saturated hydrocarbon liquid per 1 part of said asphalt.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-06-27 | 1977-12-27 | 1978-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-27 | 1981-12-27 | 1982-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-27 | 1985-12-27 | 1986-06-28 | $7700.00 | Window Closed / Lapsed |