US3781903A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magnetic imaging methods and media
Assignee: Bell and Howell Co
•
Filing: 1971-11-08
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Granted: 1973-12-25
•
Expires: 1991-11-08
Abstract
Abstract A magnetic imaging method provides a magnetic record of an input image by causing selected portions of a sheet of magnetic recording material to be magnetized substantially to a predetermined depth with alternating magnetic fields having a predetermined wavelength that is correlated to the depth of magnetization and to the diameter of magnetic toner particles employed in the printout of the magnetic record.
Inventors
- 👤 F Jeffers
- 👤 J Rolker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 03:33
CPC Classifications
G; G03; G03G; G03G19/00
Claims Analysis
Total Claims: 49
Claim 1
Independent Claim
98 words
In a method of providing an image of input information, the improvement comprising in combination the steps of: providing a magnetizable recording medium; providing a magnetic toner having magnetically attractable particles of substantially a predetermined diameter; magnetizing said recording medium in accordance with said information substantially to a predetermined depth with alternating magnetic fields having as recorded a predetermined wavelength, said toner particle diameter, said depth of magnetization and said wavelength being correlated with each other for optimized toner attraction; and applying said magnetic toner to said magnetized recording medium to provide a toner image of said information.
Claim 2
Dependent Claim
98 words
In a method of providing an image of input information, the improvement comprising in combination the steps of: providing a magnetizable recording medium; providing a magnetic toner having magnetically attractable particles of substantially a predetermined diameter; magnetizing said recording medium in accordance with said information substantially to a predetermined depth with alternating magnetic fields having as recorded a predetermined wavelength, said toner particle diameter, said depth of magnetization and said wavelength being correlated with each other for optimized toner attraction; and applying said magnetic toner to said magnetized recording medium to provide a toner image of said information.
Claim 3
Dependent Claim
90 words
A method as claimed in claim 1, wherein: said applied magnetic toner is spaced from said magnetized recording medium; and said wavelength is within a range of from pi /2 (z - h2/6z) to pi /3 (8z - h2/2) wherein h is said depth of magnetization, z is equal to s + (D+ h)/2, D is said toner particle diameter, s is the spacing between the magnetic recording medium and the applied toner particles, and pi is equal to the ratio of the circumference of a circle to its diameter.
Claim 4
Dependent Claim
64 words
A method as claimed in claim 1, wherein: said wavelength is within a range of from pi /4 (D+ h) - pi h2/6(D+ h) to 4 pi /3 (D+ h) - 2 pi h2/3(D+ h) wherein h is said depth of magnetization, D is said toner particle diameter, and pi is equal to the ratio of the circumference of a circle to its diameter.
Claim 5
Dependent Claim
99 words
A method as claimed in claim 1, wherein: said magnetic toner comprises multidomain magnetically attractable particles; said applied magnetic toner is spaced from said magnetized recording medium; and said wavelength is within a range of from 2 pi /3 (z - h2/8z) to pi /3 (8z - h2/z) wherein h is said depth of magnetization, z is equal to s + (D++ h)/2, D is said toner particle diameter, s is the spacing between the magnetic recording medium and the applied toner particles, and pi is equal to the ratio of the circumference of a circle to its diameter.
Claim 6
Dependent Claim
73 words
A method as claimed in claim 1, wherein: said magnetic toner comprises multidomain magnetically attractable particles; and said wavelength is within a range of from pi /3 (D+ h) - pi h2/6(D+ h) to 4 pi /3 (D+ h) - 2 pi h2/3(D+ h) wherein h is said depth of magnetization, D is said toner particle diameter, and pi is equal to the ratio of the circumference of a circle to its diameter.
Claim 7
Dependent Claim
99 words
A method as claimed in claim 1, wherein: said magnetic toner comprises single domain magnetically attractable particles; said applied magnetic toner is spaced from said magnetized recording medium; and said wavelength is within a range offrom pi /2 (z - h2/6z) to 2 pi z - pi h2/3z wherein h is said depth of magnetization, z is equal to s + (D+ h)/2, D is said toner particle diameter, s is the spacing between the magnetic recording medium and the applied toner particles, and pi is equal to the ratio of the circumference of a circle to its diameter.
Claim 8
Dependent Claim
71 words
A method as claimed in claim 1, wherein: said magnetic toner comprises single-domain magnetically attractable particles; and said wavelength is within a range of from pi /4 (D+ h) - pi h2/6(D+ h) to pi (D+ h) - 2 pi h2/3(D+ h) wherein h is said depth of magnetization, D is said toner particle diameter, and pi is equal to the ratio of the circumference of a circle to its diameter.
Claim 9
Dependent Claim
91 words
A method as claimed in claim 1, wherein: said magnetic toner comprises multidomain magnetically attractable particles; said applied magnetic toner is spaced from said magnetized recording medium; and said wavelength is substantially equal to 4 pi z/3 - pi h2/6z wherein h is said depth of magnetization, z is equal to s + (D+ h)/2, D is said toner particle diameter, s is the spacing between the magnetic recording medium and the applied toner particles, and pi is equal to the ratio of the circumference of a circle to its diameter.
Claim 10
Dependent Claim
61 words
A method as claimed in claim 1, wherein: said magnetic toner comprises multidomain magnetically attractable particles; and said wavelength is substantially equal to 2 pi /3 (D+ h) - pi h2/3(D+ h) wherein h is said depth of magnetization, D is said toner particle diameter, and pi is equal to the ratio of the circumference of a circle to its diameter.
Claim 11
Dependent Claim
91 words
A method as claimed in claim 1, wherein: said magnetic toner comprises single domain magnetically attractable particles; said applied magnetic toner is spaced from said magnetized recording medium; and said wavelength is substantially equal to pi z - ) h2/6z wherein h is said depth of magnetization, z is equal to s + (D+ h)/2, D is said toner particle diameter, s is the spacing between the magnetic recording medium and the applied toner particles, and pi is equal to the ratio of the circumference of a circle to its diameter.
Claim 12
Dependent Claim
61 words
A method as claimed in claim 1, wherein: said magnetic toner comprises single domain magnetically attractable particles; and said wavelength is substantially equal to pi /2 (D+ h) - pi h2/3(D+ h) wherein h is said depth of magnetization, D is said toner particle diameter, and pi is equal to the ratio of the circumference of a circle to its diameter.
Claim 13
Dependent Claim
38 words
A method as claimed in claim 1, wherein: said recording medium is magnetized in accordance with said information by magnetizing portions of said recording medium selected in accordance with said information at said wavelength and to said depth.
Claim 14
Dependent Claim
45 words
A method as claimed in claim 1, wherein: said recording medium is magnetized in accordance with said information by magnetizing said recording medium substantially uniformly at said wavelength and to said depth, and by selectively demagnetizing said magnetized recording medium in accordance with said information.
Claim 15
Dependent Claim
27 words
A method as claimed in claim 1, wherein: said recording medium is magnetized at said wavelength and to said depth of magnetization in a crossed Line pattern.
Claim 16
Dependent Claim
63 words
A method as claimed in claim 1, wherein: said recording medium is magnetized in accordance with said information by providing a magnetic pattern having said wavelength, and by selectively copying said magnetic pattern into said recording medium in accordance with said information to provide a magnetic record of said information having said wavelength and extending in said recording medium to said predetermined depth.
Claim 17
Dependent Claim
65 words
An article of manufacture for providing an image of input information with the aid of a magnetic toner having magnetically attractable particles of substantially a predetermined diameter, characterized by a magnetic recording medium magnetized substantially to a predetermined depth with alternating magnetic fields having as recorded a predetermined wavelength correlated to said depth of magnetization and to said toner particle diameter for optimized toner attraction.
Claim 18
Dependent Claim
65 words
An article of manufacture for providing an image of input information with the aid of a magnetic toner having magnetically attractable particles of substantially a predetermined diameter, characterized by a magnetic recording medium magnetized substantially to a predetermined depth with alternating magnetic fields having as recorded a predetermined wavelength correlated to said depth of magnetization and to said toner particle diameter for optimized toner attraction.
Claim 19
Dependent Claim
53 words
An article of manufacture as claimed in claim 16, wherein: said magnetic recording medium is substantially uniformly magnetized at said wavelength and to said depth whereby said article of manufacture is capable of providing said image upon demagnetization of portions distributed in accordance with said information, and upon application of said magnetic toner.
Claim 20
Dependent Claim
29 words
An article of manufacture as claimed in claim 16, wherein: said magnetization of said recording medium exists in portions of said recording medium distributed in accordance with said information.
Claim 21
Dependent Claim
78 words
An article of manufacture as claimed in claim 16, wherein said wavelength is within a range of from pi /2 (z - h2/6z) to pi /3 (8z - h2/z) wherein h is said depth of magnetization, z is equal to s + (D+ h)/2, D is said toner particle diameter, s is a spacing between the magnetic recording medium and said toner, and pi is equal to the ratio of the circumference of a circle to its diameter.
Claim 22
Dependent Claim
66 words
An article of manufacture as claimed in claim 16, wherein: said wavelength is within a range of from pi /4 (D+ h) - pi h2/6(D+ h) to 4 pi /3 (D+ h) - 2 pi h2/3(D+ h) wherein h is said depth of magnetization, D is said toner particle diameter, and pi is equal to the ratio of the circumference of a circle to its diameter.
Claim 23
Dependent Claim
89 words
An article of manufacture as claimed in claim 16, for use with magnetic toner comprising multidomain magnetically attractable particles, wherein: said wavelength is within a range of from 2 pi /3 (z - h2/8z) to pi /3 (8z - h2z) wherein h is said depth of magnetization, z is equal to s + (D+ h)/2, D is said toner particle diameter, s is a spacing between the magnetic recording medium and said toner, and pi is equal to the ratio of the circumference of a circle to its diameter.
Claim 24
Dependent Claim
76 words
An article of manufacture as claimed in claim 16, for use with magnetic toner comprising multidomain magnetically attractable particles, wherein: said wavelength is within a range of from pi /3 (D+ h) - pi h2/6(D+ h) to 4 pi /3 (D+ h) - 2 pi h2/3(D+ h) wherein h is said depth of magnetization, D is said toner particle diameter, and pi is equal to the ratio of the circumference of a circle to its diameter.
Claim 25
Dependent Claim
90 words
An article of manufacture as claimed in claim 16, for use with magnetic toner comprising single domain magnetically attractable particles, wherein: said wavelength is within a range of from pi /2 (z - h2/6z) to 2 pi z - pi h2/3z wherein h is said depth of magnetization, z is equal to s + (D+ h)/2, D is said toner particle diameter, s is a spacing between the magnetic recording medium and said toner, and pi is equal to the ratio of the circumference of a circle to its diameter.
Claim 26
Dependent Claim
72 words
An article of manufacture as claimed in claim 16, for use with magnetic toner comprising single domain magnetically attractable particles, wherein: said wavelength is within a range offrom pi /4 (D+h) - pi h2/6(D+ h) to pi (D+ h) - 2 pi h2/3(D+h) wherein h is said depth of magnetization, D is said toner particle diameter, and pi is equal to the ratio of the circumference of a circle to its diameter.
Claim 27
Dependent Claim
81 words
An article of manufacture as claimed in claim 16, for use with magnetic toner comprising multidomain magnetically attractable particles, wherein: said wavelength is substantially equal to 4 pi z3 - pi h2/6z wherein h is said depth of magnetization, z is equal to s + (D+ h)/2, D is said toner particle diameter, s is a spacing between the magnetic recording medium and said toner, and pi is equal to the ratio of the circumference of a circle to its diameter.
Claim 28
Dependent Claim
63 words
An article of manufacture as claimed in claim 16, for use with magnetic toner comprising multidomain magnetically attractable particles, wherein: said wavelength is substantially equal to 2 pi /3 (D+h) - pi h2/3(D+ h) wherein h is said depth of magnetization, D is said toner particle diameter, and pi is equal to the ratio of the circumference of a circle to its diameter.
Claim 29
Dependent Claim
83 words
An article of manufacture as claimed in claim 16, for use with magnetic toner comprising single domain magnetically attractable particles, wherein: said wavelength is substantially equal to pi z - pi h2/6z wherein h is said depth of magnetization, z is equal to s + (D+ h)/2, D is said toner particle diameter, s is a spacing between the magnetic recording medium and the applied toner particles, and pi is equal to the ratio of the circumference of a circle to its diameter.
Claim 30
Dependent Claim
64 words
An article of manufacture as claimed in claim 16, for use with magnetic toner comprising single domain magnetically attractable particles, wherein: said wavelength is substantially equal to pi /2 (D+ h) - pi h2/3(D+ h) wherein h is said depth of magnetization, D is said toner particle diameter, and pi is equal to the ratio of the circumference of a circle ot its diameter.
Claim 31
Dependent Claim
33 words
An article of manufacture as claimed in claim 16, wherein: said magnetization to said depth and at said wavelength is present at least at crossing points of a prerecorded crossed magnetic line pattern.
Claim 32
Dependent Claim
28 words
An article of manufacture as claimed in claim 16, wherein: said magnetization to said depth and at said wavelength is present in a pattern of mutually spaced dots.
Claim 33
Dependent Claim
108 words
An image of input information produced by a process comprising in combination the steps of: providing a magnetizable recording medium; providing a magnetic toner having magnetically attractable particles of substantially a predetermined diameter; magnetizing said recording medium in accordance with said information substantially to a predetermined depth with alternating magnetic fields having as recorded a predetermined wavelength, said toner particle diameter, said depth of magnetization and said wavelength being correlated with each other for optimized toner attraction; APPLYING said magnetic toner to said magnetized recording medium to provide a toner image of said information; and printing out said toner image to provide said image of the input information.
Claim 34
Dependent Claim
108 words
An image of input information produced by a process comprising in combination the steps of: providing a magnetizable recording medium; providing a magnetic toner having magnetically attractable particles of substantially a predetermined diameter; magnetizing said recording medium in accordance with said information substantially to a predetermined depth with alternating magnetic fields having as recorded a predetermined wavelength, said toner particle diameter, said depth of magnetization and said wavelength being correlated with each other for optimized toner attraction; APPLYING said magnetic toner to said magnetized recording medium to provide a toner image of said information; and printing out said toner image to provide said image of the input information.
Claim 35
Dependent Claim
90 words
An image as claimed in claim 31, wherein: said applied magnetic toner is spaced from said magnetized recording medium; and said wavelength is within a range of from pi /2 (z - h2/6z) to pi /3 (8z - h2/z) wherein h is said depth of magnetization, z is equal to s + (D+ h)/2, D is said toner particle diameter, s is the spacing between the magnetic recording medium and the applied toner particles, and pi is equal to the ratio of the circumference of a circle to its diameter.
Claim 36
Dependent Claim
63 words
A method as claimed in claim 31, wherein: said wavelength is within a range offrom pi /4 (D+ h) - pi h2/6(D+ h) to 4 pi /3 (D+ h) - 2 pi h2/3(D+ h) wherein h is said depth of magnetization, D is said toner particle diameter, and pi is equal to the ratio of the circumference of a circle to its diameter.
Claim 37
Dependent Claim
99 words
An image as claimed in claim 31, wherein: said magnetic toner comprises multidomain magnetically attractable particles; said applied magnetic toner is spaced from said magnetized recording medium; and said wavelength is within a range of from 2 pi /3 (z - h2/8z) to pi /3 (8z - h2/z) wherein h is said depth of magnetization, z is equal to s + (D+ h)/2, D is said toner particle diameter, s is the spacing between the magnetic recording medium and the applied toner particles, and pi is equal to the ratio of the circumference of a circle to its diameter.
Claim 38
Dependent Claim
72 words
An image as claimed in claim 31, wherein: said magnetic toner comprises multidomain magnetically attractable particles; and said wavelength is within a range of from pi /3 (D+ h) - pi h2/6(D+ h) to 4 pi /3 (D+h) - 2 pi h2/3(D+ h) wherein h is said depth of magnetization, D is said toner particle diameter, and pi is equal to the ratio of the circumference of a circle to its diameter.
Claim 39
Dependent Claim
100 words
An image as claimed in claim 31, wherein: said magnetic toner comprises single domain magnetically attractable particles; said applied magnetic toner is spaced from said magnetized recording medium; and said wavelength is within a range of from pi /2 (z - h2/6z) to 2 pi z - pi h2/3z wherein h is said depth of magnetization, z is equal to s + (D+ h)/2, D is said toner particle diameter, s is the spacing between the magnetic recording medium and the applied toner particles, and pi is equal to the ratio of the circumference of a circle to its diameter.
Claim 40
Dependent Claim
72 words
An image as claimed in claim 31, wherein: said magnetic toner comprises single domain magnetically attractable particles; and said wavelength is within a range of from pi /4 (D+ h) - pi h2/6(D+ h) to pi (D+ h) - 2 pi h2/3(D+ h) wherein h is said depth of magnetization, D is said toner particle diameter, and pi is equal to the ratio of the circumference of a circle to its diameter.
Claim 41
Dependent Claim
91 words
An image as claimed in claim 31, wherein: said magnetic toner comprises multidomain magnetically attractable particles; said applied magnetic toner is spaced from said magnetized recordinG medium; and said wavelength is substantially equal to 4 pi z/3 - pi h2/6z wherein h is said depth of magnetization, z is equal to s + (D+ h)/2, D is said toner particle diameter, s is the spacing between the magnetic recording medium and the applied toner particles, and pi is equal to the ratio of the circumference of a circle to its diameter.
Claim 42
Dependent Claim
61 words
An image as claimed in claim 31, wherein: said magnetic toner comprises multidomain magnetically attractable particles; and said wavelength is substantially equal to 2 pi /3 (D+ h) - pi h2/3(D+ h) wherein h is said depth of magnetization, D is said toner particle diameter, and pi is equal to the ratio of the circumference of a circle to its diameter.
Claim 43
Dependent Claim
91 words
An image as claimed in claim 31, wherein: said magnetic toner comprises single domain magnetically attractable particles; said applied magnetic toner is spaced from said magnetized recording medium; and said wavelength is substantially equal to pi z - pi h2/6z wherein h is said depth of magnetization, z is equal to s + (D+ h)/2, D is said toner particle diameter, s is the spacing beetween the magnetic recording medium and the applied toner particles, and pi is equal to the ratio of the circumference of a circle to its diameter.
Claim 44
Dependent Claim
61 words
An image as claimed in claim 31, wherein: said magnetic toner comprises single domain magnetically attractable particles; and said wavelength is substantially equal to pi /2 (D+ h) - pi h2/3(D+ h) wherein h is said depth of magnetization, D is said toner particle diameter, and pi is equal to the ratio of the circumference of a circle to its diameter.
Claim 45
Dependent Claim
38 words
An image as claimed in claim 31, wherein: said recording medium is magnetized in accordance with said information by magnetizing portions of said recording medium selected in accordance with said information at said wavelength and to said depth.
Claim 46
Dependent Claim
45 words
An image as claimed in claim 31, wherein: said recording medium is magnetized in accordance with said information by magnetizing said recording medium substantially uniformly at said wavelength and to said depth, and by selectively demagnetizing said magnetized recording medium in accordance with said information.
Claim 47
Dependent Claim
27 words
An image as claimed in claim 31, wherein: said recording medium is magnetized at said wavelength and to said depth of magnetization in a crossed line pattern.
Claim 48
Dependent Claim
38 words
An image as claimed in claim 31, wherein: said magnetization to said depth and at said wavelength is distributed in a pattern of mutually spaced dots whereby said magnetic toner image is composed of discrete spaced toner piles.
Claim 49
Dependent Claim
63 words
An image as claimed in claim 31, wherein: said recording medium is magnetized in accordance with said information by providing a magnetic pattern having said wavelength, and by selectively copying said magnetic pattern into said recording medium in accordance with said information to provide a magnetic record of said information having said wavelength and extending in said recording medium to said predetermined depth.
References Cited (Backward Citations)
US3465105A
Cited
US3641585A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-12-24 | 1977-06-25 | 1977-12-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-24 | 1981-06-25 | 1981-12-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-24 | 1985-06-25 | 1985-12-25 | $7700.00 | Window Closed / Lapsed |