US3927639A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for developing an electrostatic latent image on an electrophotographic film
Assignee: Kimberly Clark Tissue Co
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Filing: 1974-04-08
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Granted: 1975-12-23
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Expires: 1994-04-08
Abstract
Abstract Disclosed is a method and apparatus for developing an electrostatic latent image on an electrophotographic film through use of a special developing chamber forming a passageway through which electrostatically charged toner particles in a carrier liquid are conducted to contact the film and through use of special toner flow control means. The chamber has an opening bordered by a mask against which the film is placed to form a seal, an inlet and an outlet through which liquid toner and drying air enter and leave the chamber. In the preferred embodiment the apparatus further includes supply means for providing liquid toner to the chamber, a conduit leading from the toner supply means to the inlet of the developing chamber, a toner valve through which the conduit passes, a needle orifice connected to the conduit and positioned in the inlet of the chamber, means for supplying drying air through an air valve to the inlet of the chamber, vacuum means connected to the outlet of the chamber for drawing the liquid toner and air through the chamber, and means for opening and closing alternately the toner valve and the air valve to alternately draw liquid toner and drying air through the chamber. In the preferred embodiment a porous material is located in the chamber passageway for absorbing sufficient liquid toner to remain wet during the drying step and avoid permanent toner deposition in the passageway.
Inventors
- 👤 John D Plumadore
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 03:57
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/10; G03G15/101
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
285 words
In an apparatus for developing an electrostatic latent image on an electrophotographic film, comprising: a developing chamber forming a passageway through which electrostatically charged toner particles in a carrier liquid are conducted to contact the film, the chamber having an opening bordered by a mask against which the film is placed to form a seal, an inlet through which toner particles and air enter the chamber, and an outlet through which toner particles and air leave the chamber; toner supply means for providing liquid toner to be passed through the chamber; toner flow control means for permitting a predetermined quantity of liquid toner to flow through the developing chamber at predetermined times; air supply means for supplying drying air to the inlet of the chamber; and vacuum means connected to the outlet of the chamber for drawing the liquid toner and the air through the chamber, the vacuum means creating sub-atmospheric pressure within the chamber to prevent leakage of liquid toner from the chamber around the film; the improvement in the apparatus wherein the toner flow control means and the air supply means are provided by: a conduit leading from the toner supply means to the inlet of the developing chamber; a toner valve through which the conduit passes; an orifice connected to the conduit and positioned in the inlet of the developing chamber, the orifice sized to permit liquid toner to be drawn by the vacuum means into the developing chamber only when the toner valve is opened; an air valve through which passes the drying air which enters the developing chamber through the inlet; and means for opening and closing alternately the toner valve and the air valve for predetermined periods of time.
Claim 2
Dependent Claim
285 words
In an apparatus for developing an electrostatic latent image on an electrophotographic film, comprising: a developing chamber forming a passageway through which electrostatically charged toner particles in a carrier liquid are conducted to contact the film, the chamber having an opening bordered by a mask against which the film is placed to form a seal, an inlet through which toner particles and air enter the chamber, and an outlet through which toner particles and air leave the chamber; toner supply means for providing liquid toner to be passed through the chamber; toner flow control means for permitting a predetermined quantity of liquid toner to flow through the developing chamber at predetermined times; air supply means for supplying drying air to the inlet of the chamber; and vacuum means connected to the outlet of the chamber for drawing the liquid toner and the air through the chamber, the vacuum means creating sub-atmospheric pressure within the chamber to prevent leakage of liquid toner from the chamber around the film; the improvement in the apparatus wherein the toner flow control means and the air supply means are provided by: a conduit leading from the toner supply means to the inlet of the developing chamber; a toner valve through which the conduit passes; an orifice connected to the conduit and positioned in the inlet of the developing chamber, the orifice sized to permit liquid toner to be drawn by the vacuum means into the developing chamber only when the toner valve is opened; an air valve through which passes the drying air which enters the developing chamber through the inlet; and means for opening and closing alternately the toner valve and the air valve for predetermined periods of time.
Claim 3
Dependent Claim
50 words
Apparatus according to claim 1 further including control means attached to the vacuum means for providing a high vacuum and a low vacuum, the low vacuum being used to draw the liquid toner through the developing chamber, and the high vacuum being used to draw drying air through the chamber.
Claim 4
Dependent Claim
43 words
Apparatus according to claim 1, wherein the developing chamber includes a development electrode forming one wall Of the passageway for conducting the liquid toner through the developing chamber and being positioned close to the opening through which the toner particles contact the film.
Claim 5
Dependent Claim
43 words
Apparatus according to claim 3, including a porous material positioned over the electrode, the porous material being made of a nonelectrically conductive material and capable of absorbing sufficient liquid toner to remain wet while the drying air is passed through the developing chamber.
Claim 6
Dependent Claim
205 words
In an apparatus for developing an electrostatic latent image on an electrophotographic film, comprising; a developing chamber forming a passageway through which electrostatically charged toner particles in a carrier liquid are conducted to contact the film, the chamber having an opening bordered by a mask against which the film is placed to form a seal, an inlet through which liquid toner and air enter the chamber, and an outlet through which liquid toner and air leave the chamber, toner supply means for providing liquid toner to be passed through the chamber; toner flow control means for permitting a predetermined quantity of liquid toner to flow through the developing chamber at predetermined times; air supply means for supplying drying air to the inlet of the chamber; and vacuum means connected to the outlet of the chamber for drawing the liquid toner and the air through the chamber, the vacuum means creating sub-atmospheric pressure within the chamber to prevent leakage of liquid toner from the chamber around the film; the improvement wherein the developing chamber includes a porous material covering portions of the passageway walls, the porous material being capable of absorbing sufficient liquid toner to remain wet while drying air is passed through the developing chamber.
Claim 7
Dependent Claim
205 words
In an apparatus for developing an electrostatic latent image on an electrophotographic film, comprising; a developing chamber forming a passageway through which electrostatically charged toner particles in a carrier liquid are conducted to contact the film, the chamber having an opening bordered by a mask against which the film is placed to form a seal, an inlet through which liquid toner and air enter the chamber, and an outlet through which liquid toner and air leave the chamber, toner supply means for providing liquid toner to be passed through the chamber; toner flow control means for permitting a predetermined quantity of liquid toner to flow through the developing chamber at predetermined times; air supply means for supplying drying air to the inlet of the chamber; and vacuum means connected to the outlet of the chamber for drawing the liquid toner and the air through the chamber, the vacuum means creating sub-atmospheric pressure within the chamber to prevent leakage of liquid toner from the chamber around the film; the improvement wherein the developing chamber includes a porous material covering portions of the passageway walls, the porous material being capable of absorbing sufficient liquid toner to remain wet while drying air is passed through the developing chamber.
Claim 8
Dependent Claim
39 words
Apparatus according to claim 5, wherein the chamber has a development electrode forming one wall of the passageway and positioned close to the opening through which the liquid toner contacts the film, and the porous material covers the electrode.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-12-22 | 1979-06-23 | 1979-12-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-22 | 1983-06-23 | 1983-12-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-22 | 1987-06-23 | 1987-12-23 | $7700.00 | Window Closed / Lapsed |