Claims
- 1. A magnetic marking apparatus, comprising:
- a first non-opaque surface;
- a second surface spaced opposite from said first surface;
- a non-opaque dispersion medium contained between said first and second surfaces;
- a plurality of randomly oriented, magnetically active flakes in said dispersion medium, said flakes being dispersed such that said randomly oriented flakes produce a substantially uniform background when viewed through said first surface;
- a permanent magnet for aligning said flakes in the dispersion medium proximate said magnet upon the application of said magnet to one of said surfaces, whereupon said portion of said dispersion medium containing aligned flakes allows light transmission therethrough; and
- wherein the spacing between said first and second surfaces is selected so that light passing through said first surface and said portion of said dispersion medium containing said aligned flakes is transmitted to said second surface and creates an image formed by the contrast between said second surface as viewed through said first surface and said generally uniform background.
- 2. The apparatus of claim 1, wherein said second surface is colored.
- 3. The apparatus of claim 1 wherein said second surface is non-opaque and wherein a colored substrate is releasably secured to said second surface.
- 4. The apparatus of claim 1, wherein said flakes have an aspect ratio having at least two of the height, length or width measurements of about 5:1 or greater.
- 5. The apparatus of claim 1, wherein said flakes have an aspect ratio having at least two of the height, length or width measurements of about 10:1 or greater.
- 6. The apparatus of claim 1, wherein said dispersion medium includes a thixotropic agent.
- 7. The apparatus of claim 1, further comprising a spacing element for separating said first and second surfaces.
- 8. The apparatus of claim 1, wherein said first and second surfaces are part of a sealed housing that is generally filled with said dispersion medium.
- 9. The apparatus of claim 1, wherein said first and second surfaces are spaced from about 0.1 mm to about 20 mm.
- 10. The apparatus of claim 1, wherein said first and second surfaces are spaced from about 0.5 mm to about 5 mm.
- 11. A magnetic marking apparatus, comprising:
- a first non-opaque surface;
- a second colored surface spaced opposite said first surface;
- a non-opaque dispersion medium contained between said first and second surfaces;
- a plurality of randomly oriented, magnetically active flakes, in said dispersion medium, said flakes being dispersed such that said flakes produce a substantially uniform background when viewed through said first surface;
- a permanent magnet for aligning said flakes in the dispersion medium proximate said magnet upon the application of said magnet to one of said surfaces, whereupon said portion of said dispersion medium containing aligned flakes allows light transmission therethrough; and
- wherein the spacing between said first and second surfaces is selected so that light passing through said first surface and said portion of said dispersion medium containing said aligned flakes is transmitted to said second surface, thereby affording a view of said second surface through said portion of said dispersion medium containing aligned flakes and creating an image formed by the contrast between said generally uniform background and said second surface view.
- 12. The magnetic marking apparatus of claim 11, wherein said second surface is opaque.
- 13. The magnetic marking apparatus of claim 11, wherein said second surface is non-opaque and a portion of said light is transmitted through said second surface.
- 14. The magnetic marking apparatus of claim 11, wherein said flakes are colored.
- 15. The magnetic marking apparatus of claim 11, wherein said dispersion medium is colored.
- 16. The magnetic marking apparatus of claim 11, wherein said second surface is colored.
- 17. The magnetic marking apparatus of claim 11, wherein said second surface is patterned.
- 18. A magnetic marking apparatus, comprising:
- a first non-opaque surface;
- a second surface spaced opposite from said first surface;
- a separation element interposed between said first and second surfaces;
- a non-opaque dispersion medium contained between said first and second surfaces;
- a plurality of randomly oriented, magnetically active flakes in said dispersion medium, said flakes being dispersed such that said flakes produce a substantially uniform background when viewed through said first surface;
- a permanent magnet for aligning said flakes in the dispersion medium proximate said magnet upon the application of said magnet to one of said surfaces, whereupon said portion of said dispersion medium containing aligned flakes allows light transmission therethrough; and
- wherein the spacing between said first and second surfaces is selected so that said portion of said dispersion medium containing aligned flakes extends completely between said surfaces, thereby allowing light passing through said first surface and said portion of said dispersion medium containing said aligned flakes to be transmitted to said second surface.
- 19. The magnetic marking apparatus of claim 18, wherein said separation element is beads that measure from about 10-20 microns in diameter.
- 20. The magnetic marking apparatus of claim 19, wherein said beads are plastic.
- 21. The magnetic marking apparatus of claim 18, wherein said separation element is screening.
- 22. The magnetic marking apparatus of claim 21, wherein said screening is plastic.
- 23. The magnetic marking apparatus of claim 18, wherein said separation element is a plurality of posts, placed randomly between said surfaces and oriented perpendicularly to said surfaces.
- 24. The magnetic marking apparatus of claim 18, wherein said separation element is a plurality of protrusions from at least one of said surfaces toward the other of said surfaces.
- 25. A magnetic marking apparatus, comprising:
- a sealed housing, having:
- a first non-opaque surface;
- a second surface spaced opposite from said first surface, said second surface being colored; and
- a separation element interposed between said first and second surfaces;
- a non-opaque dispersion medium having a thixotropic agent and generally filling said sealed housing and having disposed therein a plurality of randomly oriented, magnetically active flakes, said flakes having an aspect ratio having at least two of the height, length or width measurements of about 5:1 or greater, said flakes being dispersed such that said randomly oriented flakes produce a substantially uniform background when viewed through said first surface;
- a permanent magnet for aligning said flakes in the dispersion medium proximate said magnet upon the application of said magnet to one of said surfaces, whereupon said portion of said dispersion medium containing aligned flakes allows light transmission therethrough; and
- wherein the spacing between said first and second surfaces is selected so that light passing through said first surface and said portion of said dispersion medium containing said aligned flakes is transmitted to said second surface, thereby affording a view of said second surface through said portion of said dispersion medium containing aligned flakes and creating a colored image formed by the contrast between said generally uniform background and said second surface view.
- 26. A magnetic marking apparatus comprising:
- a front non-opaque surface;
- a rear surface spaced opposite said front surface;
- a non-opaque dispersion medium contained between said surfaces;
- a plurality of randomly oriented, magnetically active flakes in said dispersion medium, said flakes being dispersed such that light passing through said front surface and striking said randomly oriented flakes produces a substantially uniform background as viewed through said front surface; and
- a permanent magnet for aligning said flakes in the dispersion medium proximate said magnet upon the application of said magnet to one of said surfaces, whereupon said portion of said dispersion medium containing aligned flakes allows light transmission therethrough; and
- wherein the spacing between said front and back surfaces is selected so that light passing through said front surface and said portion of said dispersion medium containing said aligned flakes is transmitted to said rear surface and wherein one of said back surface, dispersion medium or flakes is colored.
- 27. The magnetic marking apparatus of claim 26, wherein said magnetically active flakes are colored.
- 28. The magnetic marking apparatus of claim 26, wherein said rear surface is colored.
- 29. The magnetic marking apparatus of claim 28, wherein said rear surface is opaque.
- 30. The magnetic marking apparatus of claim 26, wherein said dispersion medium is colored.
- 31. The magnetic marking apparatus of claim 30, wherein said dispersion medium is colored by a transparent or translucent dye.
- 32. A magnetic marking apparatus, comprising:
- first and second spaced, non-opaque surfaces;
- a non-opaque dispersion medium contained between said first and second surfaces;
- a plurality of randomly oriented, magnetically active flakes in said dispersion medium, said flakes being dispersed such that said randomly oriented flakes produce a substantially uniform background when viewed through said first surface and such that light passing through said second surface and striking said randomly oriented flakes is prevented from reaching said first surface;
- a permanent magnet for aligning said flakes in the dispersion medium proximate said magnet upon the application of said magnet to one of said surfaces, whereupon said portion of said dispersion medium containing aligned flakes allows light transmission therethrough; and
- a light source proximate said second surface for directing light through said portion of dispersion medium containing aligned flakes and said first surface, said light creating an image viewable through said first surface by contrasting with said generally uniform background.
- 33. A magnetic marking apparatus, comprising:
- a first non-opaque surface;
- a second surface spaced opposite from said first surface;
- a non-opaque dispersion medium contained between said first and second surfaces;
- a plurality of randomly oriented, magnetically active flakes dispersed in said dispersion medium in an amount sufficient to provide opacity when randomly oriented;
- a permanent magnet for applying to one of said surfaces to align said flakes in a portion of said dispersion medium proximate said magnet; and
- wherein the distance between said first and second surfaces, the thickness and amount of said flakes, the intensity of said magnet, and the viscosity of said dispersion medium are selected so that said portion of said dispersion medium containing aligned flakes extends completely between said surfaces, thereby allowing light passing through said first surface and said portion of said dispersion medium containing said aligned flakes to be transmitted to said second surface.
- 34. The apparatus of claim 33, wherein said second surface is opaque and colored, whereby a portion of said light transmitted to said second surface is reflected back therefrom through said first surface, affording a view of said second surface through said portion of said dispersion medium containing aligned flakes and creating a colored image formed by the contrast between said generally uniform background and said second surface view.
- 35. The apparatus of claim 33, wherein said second surface is non-opaque whereby a portion of said light passing through said first surface and said portion of said dispersion medium containing said aligned flakes is also transmitted through said second surface.
- 36. The apparatus of claim 35, wherein said second surface is colored, whereby a portion of said light transmitted to said second surface is reflected back therefrom through said first surface, thereby creating a colored image formed by the contrast between said generally uniform background and said reflected light.
- 37. The apparatus of claim 35, further comprising a colored opaque member releasably secured to said second surface, whereby a portion of said light transmitted to said second surface is also transmitted to said member and reflected back from said member through said first surface, affording a view of said member through said portion of said dispersion medium containing aligned flakes and creating a colored image formed by the contrast between said generally uniform background and said member view.
- 38. The apparatus of claim 37, wherein said member is multi-colored.
- 39. The apparatus of claim 37, wherein said member has a pattern thereon.
- 40. A magnetic marking apparatus, comprising:
- first and second planar, parallel non-opaque surfaces;
- a housing supporting said non-opaque surfaces and, along with said non-opaque surfaces, defining a sealed interior space;
- a dispersion medium sealed in said interior space;
- a plurality of magnetically active particles dispersed within said dispersion medium; and
- a permanent drawing magnet outside said interior space having a magnetic field; wherein said non-opaque surfaces are spaced close enough so that the application of said drawing magnet to one of said surfaces causes movement of said particles throughout the dispersion medium proximate said drawing magnet and between said first and second non-opaque surfaces, so as to create an image on said first and second non-opaque surfaces.
- 41. The apparatus of claim 40, wherein at least one of said non-opaque surfaces is colored.
- 42. The apparatus of claim 40, wherein said image is erasable by applying pressure to one of said non-opaque surfaces.
- 43. The apparatus of claim 41, further comprising:
- a permanent erasing magnet outside said interior space for erasing said image.
- 44. A magnetic marking apparatus, comprising:
- first and second spaced, planar, parallel non-opaque surfaces;
- a housing supporting said non-opaque surfaces and, along with said non-opaque surfaces, defining a sealed interior space;
- a dispersion medium sealed in said interior space;
- a plurality of magnetically active particles dispersed within said dispersion medium;
- a permanent drawing magnet outside said interior space having a magnetic field sufficient that application of said drawing magnet to a selected point on said first non-opaque surface causes movement of said particles in a portion of said dispersion medium proximate said point and extending between said first and second non-opaque surfaces, whereby selective application of said drawing magnet to said first non-opaque surface causes movement of a selected portion of said particles and results in the creation of an image viewable through said first non-opaque surface; and
- a permanent erasing magnet outside said interior space having a magnetic field sufficient to cause movement of said particles upon application of said magnet to said non-opaque surfaces, whereby selective application of said erasing magnet to said second non-opaque surface causes movement of said selected portion of said particles and results in the erasure of said image.
- 45. The apparatus of claim 44, wherein said selective application of said drawing magnet to said first non-opaque surface also results in the creation of an image viewable through said second non-opaque surface.
- 46. A magnetic marking apparatus, comprising:
- first and second spaced, planar, parallel non-opaque surfaces;
- a housing supporting said non-opaque surfaces and, along with said non-opaque surfaces, defining a sealed interior space;
- a dispersion medium sealed in said interior space;
- a plurality of magnetically active particles dispersed within said dispersion medium;
- a permanent drawing magnet outside said interior space having a magnetic field sufficient that application of said drawing magnet to a selected point on said first non-opaque surface causes movement of said particles in a portion of said dispersion medium proximate said point and extending between said first and second non-opaque surfaces, whereby selective application of said drawing magnet to said first non-opaque surface causes movement of a selected portion of said particles and results in the creation of a first image viewable through said first non-opaque surface and a second image viewable through said second non-opaque surface.
- 47. The apparatus of claim 46, further comprising a permanent erasing magnet outside said interior space having a magnetic field sufficient to cause movement of said particles upon application of said magnet to said non-opaque surfaces, whereby selective application of said erasing magnet to said second non-opaque surface causes movement of said selected portion of said particles and results in the erasure of said first and second images.
- 48. The apparatus of claim 46, wherein at least one of said non-opaque surfaces is colored.
RELATED APPLICATIONS
This is related to and comprises a continuation-in-part of the patent application filed by the same inventors on Mar. 13, 1991, under Ser. No. 668,914, patented May 12, 1992, U.S. Pat. No. 5,112,229, which is related to and comprises a continuation of the patent application filed by the same inventors on Nov. 16, 1989, under Ser. No. 437,744, patented May 28, 1991, U.S. Pat. No. 5,018,979.
US Referenced Citations (25)
Foreign Referenced Citations (2)
Number |
Date |
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810324 |
Apr 1969 |
CAX |
2034640A |
Jun 1980 |
GBX |
Continuations (1)
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Number |
Date |
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Parent |
437744 |
Nov 1989 |
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Continuation in Parts (1)
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Number |
Date |
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668914 |
Mar 1991 |
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