US3920863A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of providing and developing hidden entries
Assignee: 3M Co
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Filing: 1973-01-11
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Granted: 1975-11-18
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Expires: 1993-01-11
Abstract
Abstract Paper-based feedback systems containing hidden entries comprising an image forming reactant selected from the group consisting of dithiooxamide, the N,N''-disubstituted derivatives of dithiooxamide and an iron-complexing compound having a benzene ring and at least two hydroxyl compounds substituted in adjacent positions on said ring. The hidden entries are developed by contacting the entries with an image-forming coreactant contained in a wax matrix in the form of a crayon or sheet.
Inventors
- 👤 Robert D Fraik
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 13:01
CPC Classifications
B; B41; B41M; B41M5/00; B41M5/025; B41M5/035; B41M5/0356; A; A63; A63F; A63F3/00; A63F3/06; A63F3/065; A63F3/0685
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
120 words
PROVIDING INTELLIGENCE IN THE FORM OF PREFERENTIALLY RADIATION-ABSORPTIVE IMAGE AREAS UPON THE SURFACE OF A SIGNIFICANTLY LESS RADIATION-ABSORPTIVE PAPER-LIKE ORGINAL SHEET, 2 JUXTAPOSING SAID ORIGINAL SHEET, A LAYER CONTAINING A NORMALLY BESTABLY SOLID VAPORIZABLE REACTANT MATERIAL, AND A RECEPTOR SHEET, SAID RECEPTOR SHEET BEING ESSENTIALLY FREE OF MATERIALS CAPABLE OF REACTING WITH SAID VAPORIZABLE REACTANT MATERIAL TO PRODUCE CONTRASTING COLORED COMPLEXES, SAID NORMALLY STABLY SOLID VAPORIZABLE REACTANT MATERIAL BEING SELECTED FROM THE GROUP CONSISTING OF: DITHIOOXAMIDE, THE N,N''-DISUBSTITUTED DERIVATIVES OF DITHIOOXAMIDE, AND A IRON-COMPLEXING COMPOUND CAPABLE OF FORMING A COLORED COMPLEX WHEREIN REACTED WITH THE IONS OF AN IRON SALT, SAID IRON-COMPLEX COMPOUND HAVING A BENZENE RING AND AT LEAST TO HYDROXYL GROUPS UBSTITUTED IN ADJACENT POSITIONS ON SAID RING,
Claim 2
Dependent Claim
120 words
PROVIDING INTELLIGENCE IN THE FORM OF PREFERENTIALLY RADIATION-ABSORPTIVE IMAGE AREAS UPON THE SURFACE OF A SIGNIFICANTLY LESS RADIATION-ABSORPTIVE PAPER-LIKE ORGINAL SHEET, 2 JUXTAPOSING SAID ORIGINAL SHEET, A LAYER CONTAINING A NORMALLY BESTABLY SOLID VAPORIZABLE REACTANT MATERIAL, AND A RECEPTOR SHEET, SAID RECEPTOR SHEET BEING ESSENTIALLY FREE OF MATERIALS CAPABLE OF REACTING WITH SAID VAPORIZABLE REACTANT MATERIAL TO PRODUCE CONTRASTING COLORED COMPLEXES, SAID NORMALLY STABLY SOLID VAPORIZABLE REACTANT MATERIAL BEING SELECTED FROM THE GROUP CONSISTING OF: DITHIOOXAMIDE, THE N,N''-DISUBSTITUTED DERIVATIVES OF DITHIOOXAMIDE, AND A IRON-COMPLEXING COMPOUND CAPABLE OF FORMING A COLORED COMPLEX WHEREIN REACTED WITH THE IONS OF AN IRON SALT, SAID IRON-COMPLEX COMPOUND HAVING A BENZENE RING AND AT LEAST TO HYDROXYL GROUPS UBSTITUTED IN ADJACENT POSITIONS ON SAID RING,
Claim 3
Independent Claim
117 words
A method of developing a latent image to proVide feedback in a paper-based feedback system, said latent image comprising an image-forming reactant material selected from the group consisting of dithiooxamide, the N,N''-disubstituted derivatives of dithiooxamide, and an iron-complexing compound capable of forming a colored complex when reacted with the ions of an iron salt, said iron-complexing compound having a benzene ring and at least two hydroxyl groups substituted in adjacent positions on said ring, said method comprising contacting said latent image with a solid wax matrix means containing an image-forming coreactant, to transfer a portion of said image-forming coreactant from said wax matrix means to said latent image and to react and render said latent image visible.
Claim 4
Independent Claim
117 words
A method of developing a latent image to proVide feedback in a paper-based feedback system, said latent image comprising an image-forming reactant material selected from the group consisting of dithiooxamide, the N,N''-disubstituted derivatives of dithiooxamide, and an iron-complexing compound capable of forming a colored complex when reacted with the ions of an iron salt, said iron-complexing compound having a benzene ring and at least two hydroxyl groups substituted in adjacent positions on said ring, said method comprising contacting said latent image with a solid wax matrix means containing an image-forming coreactant, to transfer a portion of said image-forming coreactant from said wax matrix means to said latent image and to react and render said latent image visible.
Claim 5
Dependent Claim
21 words
providing intelligence in the form of preferentially radiation-absorptive image areas upon the surface of a significantly less radiation-absorptive paper-like original sheet;
Claim 6
Dependent Claim
21 words
providing intelligence in the form of preferentially radiation-absorptive image areas upon the surface of a significantly less radiation-absorptive paper-like original sheet;
Claim 7
Dependent Claim
98 words
juxtaposing said original sheet, a layer containing a normally stably solid vaporizable reactant material, and a receptor sheet, said receptor sheet being essentially free of materials capable of reacting with said vaporizable reactant material to produce contrasting colored complexes, said normally stably solid vaporizable reactant material being selected from the group consisting of: dithiooxamide, the N,N''-disubstituted derivatives of dithiooxamide, and an iron-complexing compound capable of forming a colored complex when reacted with the ions of an iron salt, said iron-complex compound having a benzene ring and at least two hydroxyl groups substituted in adjacent positions on said ring;
Claim 8
Dependent Claim
98 words
juxtaposing said original sheet, a layer containing a normally stably solid vaporizable reactant material, and a receptor sheet, said receptor sheet being essentially free of materials capable of reacting with said vaporizable reactant material to produce contrasting colored complexes, said normally stably solid vaporizable reactant material being selected from the group consisting of: dithiooxamide, the N,N''-disubstituted derivatives of dithiooxamide, and an iron-complexing compound capable of forming a colored complex when reacted with the ions of an iron salt, said iron-complex compound having a benzene ring and at least two hydroxyl groups substituted in adjacent positions on said ring;
Claim 9
Dependent Claim
24 words
The method according to claim 1 wherein said image forming coreactant comprises a metal salt and said wax matrix contains an image-forming reaction accelerator.
Claim 10
Dependent Claim
24 words
The method according to claim 2 wherein said reaction accelerator is selected from the group consisting of organic trialkyl phosphates and organic triaryl phosphates.
Claim 11
Dependent Claim
43 words
EXPOSING THE SAID SURFACE OF SAID JUXTAPOSED ORGINAL SHEET TO A HEAT SOURCE TO INDUCE IN THE SAID IMAGE AREAS A LOCALIZED INCREASE IN TEMPERATURE AND A CORRESPONDING LOCALIZED VAPOR TRANSFER OF SAID VAPORIZABLE REACTANT MATERIAL FROM SAID LAYER TO SAID RECEPTOR SHEET,
Claim 12
Dependent Claim
43 words
EXPOSING THE SAID SURFACE OF SAID JUXTAPOSED ORGINAL SHEET TO A HEAT SOURCE TO INDUCE IN THE SAID IMAGE AREAS A LOCALIZED INCREASE IN TEMPERATURE AND A CORRESPONDING LOCALIZED VAPOR TRANSFER OF SAID VAPORIZABLE REACTANT MATERIAL FROM SAID LAYER TO SAID RECEPTOR SHEET,
Claim 13
Dependent Claim
43 words
exposing the said surface of said juxtaposed original sheet to a heat source to induce in the said image areas a localized increase in temperature and a corresponding localized vapor transfer of said vaporizable reactant material from said layer to said receptor sheet;
Claim 14
Dependent Claim
43 words
exposing the said surface of said juxtaposed original sheet to a heat source to induce in the said image areas a localized increase in temperature and a corresponding localized vapor transfer of said vaporizable reactant material from said layer to said receptor sheet;
Claim 15
Dependent Claim
36 words
PERMITTING THE VAPOR TRANSFERRED, VAPORIZABLE REACTANT MATERIAL TO CONDENSE ON THE RECEPTOR SHEET, THEREBY PROVIDING A STORABLE LATENT IMAGE IN LOCALIZED AREAS OF SAID RECEPTOR SHEET CORRESPONDING TO SAID IMAGE AREAS OF SAID ORIGINAL SHEET, AND
Claim 16
Dependent Claim
36 words
PERMITTING THE VAPOR TRANSFERRED, VAPORIZABLE REACTANT MATERIAL TO CONDENSE ON THE RECEPTOR SHEET, THEREBY PROVIDING A STORABLE LATENT IMAGE IN LOCALIZED AREAS OF SAID RECEPTOR SHEET CORRESPONDING TO SAID IMAGE AREAS OF SAID ORIGINAL SHEET, AND
Claim 17
Independent Claim
113 words
A METHOD OF DEVELOPING A LATENT IMAGE TO PROVIDE FEEDBACK IN A PAPER-BASED FEEDBACK SYSTE, SAID LATENT IMAGE COMPRISING AN IMAGE-FORMING REACTANT MATERIAL SELECTED FROM THE GROUP CONSISTING OF DITHIOOXAMIDE, THE N,N''-DISULBSTITUTED DERIVATIVES OF DITHIOOXAMIDE, AND AN IRON-COMPLEXING COMPOUND CAPABLE OF FORMING A COLORED COMPLED WHEN REACTED ITH THE IONS OF AN IRON SALT, SAID IRON-COMPLEXING COMPOUND HAVING A BENZENE RING AND AT LEAST TO HYDROXYL GROUP SUBSTITUTED IN ADJACENT POSITIONS ON SAID RING, SAID METHOD COMPRISING CONTACTING SAID LATENT IMAGE WITH A SHEET-LIKE MEANS TO SAID DISPENSING AN IMAGE-FORMING COREACTANT TO TRANSFER SAID IMAGE-FORMING COREACTANT FROM SAID SHEET-LIKE MEANS TO SAID LATENT IMAGE AND TO REACT AND RENDER SAID LATENT IMAGE VISIBLE.
Claim 18
Independent Claim
113 words
A METHOD OF DEVELOPING A LATENT IMAGE TO PROVIDE FEEDBACK IN A PAPER-BASED FEEDBACK SYSTE, SAID LATENT IMAGE COMPRISING AN IMAGE-FORMING REACTANT MATERIAL SELECTED FROM THE GROUP CONSISTING OF DITHIOOXAMIDE, THE N,N''-DISULBSTITUTED DERIVATIVES OF DITHIOOXAMIDE, AND AN IRON-COMPLEXING COMPOUND CAPABLE OF FORMING A COLORED COMPLED WHEN REACTED ITH THE IONS OF AN IRON SALT, SAID IRON-COMPLEXING COMPOUND HAVING A BENZENE RING AND AT LEAST TO HYDROXYL GROUP SUBSTITUTED IN ADJACENT POSITIONS ON SAID RING, SAID METHOD COMPRISING CONTACTING SAID LATENT IMAGE WITH A SHEET-LIKE MEANS TO SAID DISPENSING AN IMAGE-FORMING COREACTANT TO TRANSFER SAID IMAGE-FORMING COREACTANT FROM SAID SHEET-LIKE MEANS TO SAID LATENT IMAGE AND TO REACT AND RENDER SAID LATENT IMAGE VISIBLE.
Claim 19
Independent Claim
12 words
A METHOD OF PROVIDING AND DEVELOPING HIDDEN ENTRIES COMPRISING THE STEPS OF:
Claim 20
Independent Claim
12 words
A METHOD OF PROVIDING AND DEVELOPING HIDDEN ENTRIES COMPRISING THE STEPS OF:
Claim 21
Dependent Claim
41 words
CONTACTING SAID STORABLE LATENT IMAGE WITH A SOLID WAX MATRIX MEANS CONTAINING AN IMAGE-FORMING COREACTANT WHEREBY A PORTION OF SAID IMAGE FORMING COREACTANT IS TRANSFERRED FROM SAID WAX MATRIX MEANS TO SAID STORABLE LATENT IMAGE AND SAID IMAGE IS RENDERED VISIBLE.
Claim 22
Dependent Claim
41 words
CONTACTING SAID STORABLE LATENT IMAGE WITH A SOLID WAX MATRIX MEANS CONTAINING AN IMAGE-FORMING COREACTANT WHEREBY A PORTION OF SAID IMAGE FORMING COREACTANT IS TRANSFERRED FROM SAID WAX MATRIX MEANS TO SAID STORABLE LATENT IMAGE AND SAID IMAGE IS RENDERED VISIBLE.
Claim 23
Dependent Claim
49 words
The method according to claim 5 wherein said layer of normally stably solid vaporizable reactant material comprises a coating on one major surface of the said original sheet; said juxtaposing, exposing, and permitting steps are repeated with additional receptor sheets to form additional copies of said latent-imaged receptor sheet.
Claim 24
Dependent Claim
32 words
A method according to claim 6 whErein the said coreactant is a metal salt, the metal of said metal salt being selected from the group consisting of nickel, copper, cobalt, and cadmium.
Claim 25
Dependent Claim
27 words
A method according to claim 5 wherein said original sheet contains a layer of said iron-complexing compound, said layer comprising a mirror image of said latent image.
Claim 26
Dependent Claim
16 words
A method according to claim 5 wherein said heat source is a source of infrared radiation.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-11-17 | 1979-05-19 | 1979-11-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-17 | 1983-05-19 | 1983-11-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-17 | 1987-05-19 | 1987-11-18 | $7700.00 | Window Closed / Lapsed |