US4582774A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Liquid developing latent electrostatic images and gap transfer
Assignee: HP Indigo BV
•
Filing: 1984-12-11
•
Granted: 1986-04-15
•
Expires: 2004-12-11
Abstract
Abstract A composition for developing latent electrostatic images comprising an aliphatic hydrocarbon carrier liquid having dispersed therethrough charged pigmented toner particles having a low charge to mass ratio. The composition has an amount of spacer particles having their smallest diameter greater than twenty microns and greatest diameter less than seventy microns disseminated therethrough. The spacer particles are adapted to form an air gap between the developed electrostatic image on a photoconductor, or dielectric support, and the medium to which the developed image is to be transferrred. The population of the spacer particles is such that their interparticle distance on the photoconductor is four millimeters or less. The spacer particles may be formed of any desired material, insoluble in the carrier liquid, and have any desired shape. A tetrahedral pyramidal shape or spherical shape is preferred.
Inventors
- 👤 Benzion Landa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 15:37
CPC Classifications
G; G03; G03G; G03G9/00; G03G9/08; G03G9/12
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
68 words
In a process for developing a latent image on an imaging surface by electrophoresis and transferring the developed image from said surface to a copy sheet, a liquid developer including in combination a normally liquid dielectric carrier, charged toner particles dispersed in said carried liquid, and dielectric particles dispersed in said carrier liquid, said dielectric particles having a size of at least twenty but less than forty microns.
Claim 2
Dependent Claim
68 words
In a process for developing a latent image on an imaging surface by electrophoresis and transferring the developed image from said surface to a copy sheet, a liquid developer including in combination a normally liquid dielectric carrier, charged toner particles dispersed in said carried liquid, and dielectric particles dispersed in said carrier liquid, said dielectric particles having a size of at least twenty but less than forty microns.
Claim 3
Dependent Claim
20 words
A process as in claim 1 wherein the toner particles have an average size of the order of five microns.
Claim 4
Dependent Claim
21 words
A process as in claim 1 wherein the toner particles have a size of the order of three to seven microns.
Claim 5
Dependent Claim
18 words
A process as in claim 1 wherein the dielectric particles have a size of at least thirty microns.
Claim 6
Dependent Claim
123 words
In a process for developing a latent image on an imaging surface by electrophoresis and transferring the developed image from said surface to a copy sheet, a liquid developer including in combination a dielectric liquid carrier, charged toner particles dispersed in said carrier, the developed image on said surface having a height determined by the charge-to-mass ratio of said toner particles, and dielectric spacing particles dispersed in said carrier, said spacing particles having a size greater than said height and being operative during transfer to space the copy sheet and the imaging surface apart a distance greater than said height and provide a gap between the developed image and the copy sheet, said spacing particles having a size between twenty and seventy microns.
Claim 7
Dependent Claim
123 words
In a process for developing a latent image on an imaging surface by electrophoresis and transferring the developed image from said surface to a copy sheet, a liquid developer including in combination a dielectric liquid carrier, charged toner particles dispersed in said carrier, the developed image on said surface having a height determined by the charge-to-mass ratio of said toner particles, and dielectric spacing particles dispersed in said carrier, said spacing particles having a size greater than said height and being operative during transfer to space the copy sheet and the imaging surface apart a distance greater than said height and provide a gap between the developed image and the copy sheet, said spacing particles having a size between twenty and seventy microns.
Claim 8
Dependent Claim
20 words
A process as in claim 5 wherein the toner particles have an average size of the order of five microns.
Claim 9
Dependent Claim
21 words
A process as in claim 5 wherein the toner particles have a size of the order of three to seven microns.
Claim 10
Dependent Claim
34 words
A process as in claim 5 wherein the concentration of spacing particles is sufficiently great that non-image areas of the imaging surface have deposited thereon spacing particles separated by distances less than four millimeters.
Claim 11
Dependent Claim
143 words
In a process for developing a latent image on an imaging surface by electrophoresis in the presence of an electrostatic field from a development electrode and transferring the developed image from said surface to a copy sheet, a liquid developer including in combination a dielectric liquid carrier, charged toner particles dispersed in said carrier, the image developed on said surface in the presence of said electrostatic field having a generally uniform height determined by the charge-to-mass ratio of said toner particles, and dielectric spacing particles dispersed in said carrier, said spacing particles having a size greater than said height and being operative during transfer to space the copy sheet and the imaging surface apart a distance greater than said height and provide a gap between the developed image and the copy sheet, said spacing particles having a size between twenty and seventy microns.
Claim 12
Dependent Claim
143 words
In a process for developing a latent image on an imaging surface by electrophoresis in the presence of an electrostatic field from a development electrode and transferring the developed image from said surface to a copy sheet, a liquid developer including in combination a dielectric liquid carrier, charged toner particles dispersed in said carrier, the image developed on said surface in the presence of said electrostatic field having a generally uniform height determined by the charge-to-mass ratio of said toner particles, and dielectric spacing particles dispersed in said carrier, said spacing particles having a size greater than said height and being operative during transfer to space the copy sheet and the imaging surface apart a distance greater than said height and provide a gap between the developed image and the copy sheet, said spacing particles having a size between twenty and seventy microns.
Claim 13
Dependent Claim
20 words
A process as in claim 9 wherein the toner particles have an average size of the order of five microns.
Claim 14
Dependent Claim
34 words
A process as in claim 9 wherein the concentration of spacing particles is sufficiently great that non-image areas of the imaging surface have deposited thereon spacing particles separated by distances less than four millimeters.
Claim 15
Dependent Claim
186 words
In a process for developing a latent image on an imaging surface by electrophoresis, subjecting the developed image to the metering action of a reverse roller, and transferring the metered developed image to a copy sheet, a liquid developer including in combination a dielectric liquid carrier, charged toner particles dispersed in said carrier, the image developed on said surface having a height determined by the charge-to-mass ratio of said toner particles, said reverse roller being operative to decrease the thickness of a carrier liquid layer associated with the developed image to a value less than said height, and dielectric spacing particles dispersed in said carrier, said spacing particles having a size greater than said height and being operative during transfer to space the copy sheet and the imaging surface apart a distance greater than said height and provide an air gap between the developed image and the copy sheet, said spacing particles having a size between twenty and seventy microns, said air gap being effective to reduce the quantity of carrier liquid transferred from the imaging surface to the copy sheet concomitantly with the developed image.
Claim 16
Dependent Claim
186 words
In a process for developing a latent image on an imaging surface by electrophoresis, subjecting the developed image to the metering action of a reverse roller, and transferring the metered developed image to a copy sheet, a liquid developer including in combination a dielectric liquid carrier, charged toner particles dispersed in said carrier, the image developed on said surface having a height determined by the charge-to-mass ratio of said toner particles, said reverse roller being operative to decrease the thickness of a carrier liquid layer associated with the developed image to a value less than said height, and dielectric spacing particles dispersed in said carrier, said spacing particles having a size greater than said height and being operative during transfer to space the copy sheet and the imaging surface apart a distance greater than said height and provide an air gap between the developed image and the copy sheet, said spacing particles having a size between twenty and seventy microns, said air gap being effective to reduce the quantity of carrier liquid transferred from the imaging surface to the copy sheet concomitantly with the developed image.
Claim 17
Dependent Claim
20 words
A process as in claim 12 wherein the toner particles have an average size of the order of five microns.
Claim 18
Dependent Claim
33 words
A process as in claim 12 the concentration of spacing particles is sufficiently great that non-image areas of the imaging surface have deposited thereon spacing particles separated by distances less than four millimeters.
Claim 19
Dependent Claim
204 words
In a process for developing a latent image on an imaging surface by electrophoresis in the presence of an electrostatic field from a development electrode, subjecting the developed image to the metering action of a reverse roller, and transferring the metered developed image to a copy sheet, a liquid developer including in combination a dielectric liquid carrier, charged toner particles dispersed in said carrier, the image developed on said surface in the presence of said field having a generally uniform height determined by the charge-to-mass ratio of said toner particles, said reverse roller being operative to decrease the thickness of a carrier liquid layer associated with the developed image to a value less than said height, and dielectric spacing particles dispersed in said carrier, said spacing particles having a size greater than said height and being operative during transfer to space the copy sheet and the imaging surface apart a distance greater than height and provide an air gap between the developed image and the copy sheet, said spacing particles having a size between twenty and seventy microns, said air gap being effective to reduce the quantity of carrier liquid transferred from the imaging surface to the copy sheet concomitantly with the developed image.
Claim 20
Dependent Claim
204 words
In a process for developing a latent image on an imaging surface by electrophoresis in the presence of an electrostatic field from a development electrode, subjecting the developed image to the metering action of a reverse roller, and transferring the metered developed image to a copy sheet, a liquid developer including in combination a dielectric liquid carrier, charged toner particles dispersed in said carrier, the image developed on said surface in the presence of said field having a generally uniform height determined by the charge-to-mass ratio of said toner particles, said reverse roller being operative to decrease the thickness of a carrier liquid layer associated with the developed image to a value less than said height, and dielectric spacing particles dispersed in said carrier, said spacing particles having a size greater than said height and being operative during transfer to space the copy sheet and the imaging surface apart a distance greater than height and provide an air gap between the developed image and the copy sheet, said spacing particles having a size between twenty and seventy microns, said air gap being effective to reduce the quantity of carrier liquid transferred from the imaging surface to the copy sheet concomitantly with the developed image.
Claim 21
Dependent Claim
20 words
A process as in claim 15 wherein the toner particles have an average size of the order of five microns.
Claim 22
Dependent Claim
34 words
A process as in claim 15 wherein the concentration of spacing particles is sufficiently great that non-image areas of the imaging surface have deposited thereon spacing particles separated by distances less than four millimeters.
Claim 23
Dependent Claim
49 words
A process as in claim 15 wherein the toner particles have an average size of the order of five microns and wherein the concentration of spacing particles is sufficiently great that non-image areas of the imaging surface have deposited thereon spacing particles separated by distances less than four millimeters.
Claim 24
Dependent Claim
101 words
In a process for developing a latent image on an imaging surface by electrophoresis and transferring the developed image from said surface to a copy sheet, a liquid developer including in combination a dielectric liquid carrier, charged toner particles dispersed in said carrier, and dielectric particles dispersed in said carrier, said dielectric particles having a size between twenty and seventy microns, said toner particles having an average size of the order of five microns, the concentration of dielectric particles being sufficiently great that non-image areas of the imaging surface have deposited thereon dielectric particles separated by distances less than four millimeters.
Claim 25
Dependent Claim
101 words
In a process for developing a latent image on an imaging surface by electrophoresis and transferring the developed image from said surface to a copy sheet, a liquid developer including in combination a dielectric liquid carrier, charged toner particles dispersed in said carrier, and dielectric particles dispersed in said carrier, said dielectric particles having a size between twenty and seventy microns, said toner particles having an average size of the order of five microns, the concentration of dielectric particles being sufficiently great that non-image areas of the imaging surface have deposited thereon dielectric particles separated by distances less than four millimeters.
Claim 26
Dependent Claim
21 words
A process as in claim 19 wherein the toner particles have a size of the order of three to seven microns.
References Cited (Backward Citations)
CA682502A
Cited
US3336906A
Cited
US3795530A
Cited
US3766072A
Cited
US3850830A
Cited
US3915874A
Cited
US4049446A
Cited
US4454215A
Cited
US4413048A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-04-14 | 1989-10-14 | 1990-04-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-04-14 | 1993-10-14 | 1994-04-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-04-14 | 1997-10-14 | 1998-04-15 | $7700.00 | Window Closed / Lapsed |