US3780462A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Luminous indicators involving phosphors
Assignee: Canrad Precision Industries Inc
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Filing: 1972-10-20
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Granted: 1973-12-25
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Expires: 1992-10-20
Abstract
Abstract Luminescent, specifically phosphorescent, indicia or insignia are disposed on a visible translucent substrate mounted on a carrier wherein an artificial light source is disposed within the carrier rearwardly and spacedly of the substrate so that the heat of the source of light will not affect the luminescent properties of the phosphorescent indicia or insignia which latter are formed of homogeneously dispersed phosphor particles in glass or porcelain frit, and as such are bonded to the substrate.
Inventors
- 👤 A Pregel
- 👤 W Goldman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 22:01
CPC Classifications
G; G09; G09F; G09F13/00; G09F13/20; C; C09; C09K; C09K11/00; C09K11/08; C09K11/56; C09K11/562; C09K11/565
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
14 words
A substrste as defined in claim 1, wherein said glass frit comprises said indicia.
Claim 2
Dependent Claim
30 words
A substrate as defined in claim 1, wherein said glass frit forms said indicia by occupying that part of the surface of said substrate comprising the background of said indicia.
Claim 3
Dependent Claim
63 words
A substrate as defined in claim 1, wherein said surface is the front surface of said substrate and those portions of the back surface in alignment with said glass frit on said front surface are covered with a translucent white enamel which serves to enhance by reflection the visibility of said phosphorescent material in the event of failure of ambient or artificial light.
Claim 4
Dependent Claim
27 words
A substrate as defined in claim 1, wherein said glass frit and said phosphorescent material range in size between 15 and 45 microns in the unbonded state.
Claim 5
Dependent Claim
190 words
An indicia-carrying substrate normally visible by ambient light in front thereof or by artificial light therebehind and visible by phosphorescence subsequent to failure of said ambient light or artificial light, said substrate serving to indicate avenues of ingress and egress, comprising a metal substrate, a white frit fired to substantially the entire front surface thereof, a porcelain frit forming indicia fired thereto, a phosphorescent material selected from the group consisting of ZnS and CdS dispersed in said porcelain frit, the ratio of said frit to said phosphorescent material lying in the range from 1:1 to 1: 5, and a film of translucent red paint covering at least those portions of said substrate not covered by said porcelain frit, one of said frit and said paint serving as the background for the other, whereby the contrast in color between the areas covered by said phosphorescent fired porcelain frit and by said paints makes said indicia more clearly visible whether said substrate is or is not illuminated, said phosphorescent material having the characteristic of glowing for a substantial period of time subsequent to failure of ambient or artificial illumination of said substrate.
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) | 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 |