GB698994A - Method and apparatus for developing electrostatic images - Google Patents
Method and apparatus for developing electrostatic imagesInfo
- Publication number
- GB698994A GB698994A GB2932851A GB2932851A GB698994A GB 698994 A GB698994 A GB 698994A GB 2932851 A GB2932851 A GB 2932851A GB 2932851 A GB2932851 A GB 2932851A GB 698994 A GB698994 A GB 698994A
- Authority
- GB
- United Kingdom
- Prior art keywords
- potential
- grid
- powder
- plate
- development
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G15/00—Apparatus for electrographic processes using a charge pattern
- G03G15/06—Apparatus for electrographic processes using a charge pattern for developing
- G03G15/08—Apparatus for electrographic processes using a charge pattern for developing using a solid developer, e.g. powder developer
- G03G15/0803—Apparatus for electrographic processes using a charge pattern for developing using a solid developer, e.g. powder developer in a powder cloud
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05B—SPRAYING APPARATUS; ATOMISING APPARATUS; NOZZLES
- B05B5/00—Electrostatic spraying apparatus; Spraying apparatus with means for charging the spray electrically; Apparatus for spraying liquids or other fluent materials by other electric means
- B05B5/08—Plant for applying liquids or other fluent materials to objects
- B05B5/087—Arrangements of electrodes, e.g. of charging, shielding, collecting electrodes
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Printing Methods (AREA)
Abstract
698,994. Powder development of electrostatic images. BATTELLE DEVELOPMENT CORPORATION. Dec. 14, 1951, No. 29328/51. Class 98 (ii). [Also in Group XVI] A method of developing an electrostatic image on an insulating layer disposed on a conductive support comprises positioning an electrode at a distance less than 0.5 inch from the layer and introducing a charged finely-divided material between the electrode and the layer whereby a faithful development of the image is achieved. Preferably the electrode is a grid through which the developer particles are introduced into the space between the layer and the grid. Development may be effected in steps with the electrode at different potentials for each step to control contrast. As shown, a plate comprising a conducting support 26 and an insulating layer 35 bearing an electrostatic image is placed face downward on an insulating support over an inverted metal cone 21, at the apex of which is disposed a brush 22 and a developer mixture 55 comprising a powder such as a powdered resin and a granular carrier such as oil-freed soya bean protein, the powder and carrier acquiring charges tribo-electrically. The support 26 is earthed and a grid 27 adjacent the plate is raised to a suitable potential by means of an adjustable tap 52 on a potential divider 51, thereby rendering uniform the field adjacent the image-bearing portions of the plate, typically to the potential of the highlight areas of the plate if these are to remain clear after development. The brush 22 is then rotated by means of an electric motor 23 and the resulting air dispersion of the powder 55 passes through the grid 27 to develop the plate image. In order to obtain a linear relation between the print and original densities by compensating for the logarithmic type of relation between the density of the print and of the original, the electrostatic image may be developed in steps, each comprising raising the grid to the potential corresponding to a particular tone of the original and developing for a time such that the density of the deposited developer powder at a point where the departure from linearity of the image density becomes appreciable reaches a value in a chosen fixed ratio to the density of the corresponding tone in the original. Typically development is effected with the grid successively at the potential of the highlights, middle tones, and dark shadow areas. In a modification, the grid potential is varied in equal steps continuously during the developing period, the different potentials being maintained for different times, chosen for a particular kind of plate and developer, by means of a switch having a motor-driven wiper passing over stationary contact strips of different lengths connecting resistors arranged in series across a battery as a potential divider. The potential so varied may be superimposed on an additional steady potential applied to the grid by means of an adjustable tap on a potential divider disposed across a second battery. A charge may also be produced on developing powder particles by corona discharge by blowing the powder down a tube having a wire passing down its centre raised to a high potential. In a further embodiment the plate is developed by an air dispersion of charged drops of liquid, such as Indian ink, a solution of a water-soluble blue dye, an oil dispersion of colloidal graphite, printer's ink in carbon tetrachloride, an alcoholsoluble dye in ethanol, mimeograph ink, or lampblack in methanol, the drops being formed by an air brush which emits the drops through a ring insulated from it and raised to a high potential. Specification 679,715 is referred to.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB2932851A GB698994A (en) | 1951-12-14 | 1951-12-14 | Method and apparatus for developing electrostatic images |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB2932851A GB698994A (en) | 1951-12-14 | 1951-12-14 | Method and apparatus for developing electrostatic images |
Publications (1)
Publication Number | Publication Date |
---|---|
GB698994A true GB698994A (en) | 1953-10-28 |
Family
ID=10289813
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB2932851A Expired GB698994A (en) | 1951-12-14 | 1951-12-14 | Method and apparatus for developing electrostatic images |
Country Status (1)
Country | Link |
---|---|
GB (1) | GB698994A (en) |
Cited By (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2777418A (en) * | 1954-02-08 | 1957-01-15 | Haloid Co | Apparatus for developing a powder image on a xerographic plate |
US2811135A (en) * | 1954-12-29 | 1957-10-29 | Haloid Co | Powder charging device |
US2815330A (en) * | 1955-03-14 | 1957-12-03 | Haloid Co | Generator of aerosol of powder in gas |
US2817598A (en) * | 1955-02-01 | 1957-12-24 | Haloid Co | Continuous tone reversal development process |
US2842456A (en) * | 1955-08-30 | 1958-07-08 | Battelle Development Corp | Process for developing an electrostatic image |
US2859128A (en) * | 1955-03-14 | 1958-11-04 | Haloid Xerox Inc | Method of developing xerographic image |
US2861543A (en) * | 1954-06-14 | 1958-11-25 | Haloid Xerox Inc | Apparatus for development of electrostatic image |
US2872338A (en) * | 1955-04-18 | 1959-02-03 | Haloid Xerox Inc | Electrophotographic developing process |
US2891911A (en) * | 1955-06-06 | 1959-06-23 | Gen Dynamics Corp | Developer for electrostatic printing |
US2913353A (en) * | 1955-02-08 | 1959-11-17 | Gen Dynamics Corp | Method and apparatus for developing electrostatic image |
US3010842A (en) * | 1955-08-29 | 1961-11-28 | Xerox Corp | Development of electrostatic images |
CN118033935A (en) * | 2024-04-01 | 2024-05-14 | 湖北欧雷玛科技有限公司 | Electrode manufacturing method of VA liquid crystal display |
-
1951
- 1951-12-14 GB GB2932851A patent/GB698994A/en not_active Expired
Cited By (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2777418A (en) * | 1954-02-08 | 1957-01-15 | Haloid Co | Apparatus for developing a powder image on a xerographic plate |
US2861543A (en) * | 1954-06-14 | 1958-11-25 | Haloid Xerox Inc | Apparatus for development of electrostatic image |
US2811135A (en) * | 1954-12-29 | 1957-10-29 | Haloid Co | Powder charging device |
US2817598A (en) * | 1955-02-01 | 1957-12-24 | Haloid Co | Continuous tone reversal development process |
US2913353A (en) * | 1955-02-08 | 1959-11-17 | Gen Dynamics Corp | Method and apparatus for developing electrostatic image |
US2815330A (en) * | 1955-03-14 | 1957-12-03 | Haloid Co | Generator of aerosol of powder in gas |
US2859128A (en) * | 1955-03-14 | 1958-11-04 | Haloid Xerox Inc | Method of developing xerographic image |
US2872338A (en) * | 1955-04-18 | 1959-02-03 | Haloid Xerox Inc | Electrophotographic developing process |
US2891911A (en) * | 1955-06-06 | 1959-06-23 | Gen Dynamics Corp | Developer for electrostatic printing |
US3010842A (en) * | 1955-08-29 | 1961-11-28 | Xerox Corp | Development of electrostatic images |
US2842456A (en) * | 1955-08-30 | 1958-07-08 | Battelle Development Corp | Process for developing an electrostatic image |
CN118033935A (en) * | 2024-04-01 | 2024-05-14 | 湖北欧雷玛科技有限公司 | Electrode manufacturing method of VA liquid crystal display |
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