US4343008A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for creating magnetic masters
Assignee: Xerox Corp
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Filing: 1980-07-28
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Granted: 1982-08-03
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Expires: 2000-07-28
Abstract
Abstract A magnetic master is provided by premagnetizing a magnetizable recording member, forming characters on the backing layer of the recording member with a typewriter or suitable marking means, and exposing the recording member from the backing layer side to flash energy to demagnetize the background areas and form a latent magnetic image. The latent magnetic image may be contacted with a magnetic toner and the developed image transferred to a receiving surface where it is permanently fixed. The magnetic master may be developed hundreds or thousands of times to produce the desired number of prints.
Inventors
- 👤 J. Kirk Swigert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 01:00
CPC Classifications
G; G03; G03G; G03G19/00
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
172 words
A method of magnetic imaging which comprises, (1) providing a magnetic master which is prepared by premagnitizing a magnetizable recording member at a spatial magnetization wavelength of between about 20 microns and about 120 microns, (2) causing characters to be formed on the backing layer of the recording member with suitable marking means, (3) exposing the backing layer of the recording member to a flash energy source having an energy of at least about 2.6×10 6 ergs/cm 2 , wherein background areas on the backing layer are de-magnetized thereby resulting in the formation of a latent magnetic image on the recording member, (4) contacting the latent magnetic image with a magnetic toner causing development thereof, (5) followed by transferring the developed image to a receiving surface, and subsequently repeatedly developing the magnetic latent image contained on the recording member, resulting in the production of numerous developed images, wherein the recording member is comprised of a transparent substrate containing a magnetizable material therein, which becomes paramagnetic upon exposure to said flash energy source.
Claim 2
Independent Claim
172 words
A method of magnetic imaging which comprises, (1) providing a magnetic master which is prepared by premagnitizing a magnetizable recording member at a spatial magnetization wavelength of between about 20 microns and about 120 microns, (2) causing characters to be formed on the backing layer of the recording member with suitable marking means, (3) exposing the backing layer of the recording member to a flash energy source having an energy of at least about 2.6×10 6 ergs/cm 2 , wherein background areas on the backing layer are de-magnetized thereby resulting in the formation of a latent magnetic image on the recording member, (4) contacting the latent magnetic image with a magnetic toner causing development thereof, (5) followed by transferring the developed image to a receiving surface, and subsequently repeatedly developing the magnetic latent image contained on the recording member, resulting in the production of numerous developed images, wherein the recording member is comprised of a transparent substrate containing a magnetizable material therein, which becomes paramagnetic upon exposure to said flash energy source.
Claim 3
Dependent Claim
21 words
A method in accordance with claim 1 wherein the recording member comprises a magnetic tape containing a chromium dioxide recording surface.
Claim 4
Dependent Claim
15 words
A method of imaging in accordance with claim 1 wherein the receiving surface is paper.
Claim 5
Dependent Claim
12 words
The method of claim 1 wherein said marking means comprises a typewriter.
Claim 6
Dependent Claim
19 words
The method of claim 1 wherein said magnetic toner comprises a fusible resinous component and a magnetically attractable component.
Claim 7
Dependent Claim
15 words
The method of claim 1 including permanently fixing said developed image to said receiving surface.
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) | 1985-08-02 | 1986-02-01 | 1986-08-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-08-02 | 1990-02-01 | 1990-08-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-08-02 | 1994-02-01 | 1994-08-03 | $7700.00 | Window Closed / Lapsed |