US4702497A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of encoding a symbol or message on a plastic material and an article on which a symbol has been so encoded
Assignee: Individual
•
Filing: 1986-05-02
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Granted: 1987-10-27
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Expires: 2006-05-02
Abstract
Abstract The method includes the steps of inscribing or imprinting a symbol or message on a substantially flat surface of a block of plastic while the same is at an elevated temperature by the application of pressure to said surface. The plastic block is then cooled to approximately room temperature and all visible evidence of the inscription is "erased" by physically removing, as by grinding, the superficial layer of material which bears the visible inscription. The inscription is made to reappear on the surface of the remaining block of plastic by heating the same to approximately the elevated temperature at which the inscription was made until the symbol or message reappears.
Inventors
- 👤 Tomas H. Newbery
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 04:12
CPC Classifications
B; B29; B29C; B29C59/00; B29C59/18; B29K; B29K2033/00; B29K2033/04; B29K2033/12; Y; Y10; Y10S; Y10S283/00; Y10S283/901; Y10S283/904; Y10S428/00; Y10S428/913; Y10S428/916; Y10T; Y10T428/00; Y10T428/24; Y10T428/24628; Y10T428/24736
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
100 words
A method of making reappear a symbol by message that has been encoded on a block of plastic or enscribing under pressure the symbol or message on a surface of the block while said block is at an elevated temperature, cooling said block to approximately room temmperature and physically removing the inscription while the block is at approximately room temperature, said method of making the symbol or message reappear comprising the steps of heating the block so previously treated to approximately the temperature at which the symbol or message was enscribed, said heating continuing until the symbol or message reappears.
Claim 2
Independent Claim
100 words
A method of making reappear a symbol by message that has been encoded on a block of plastic or enscribing under pressure the symbol or message on a surface of the block while said block is at an elevated temperature, cooling said block to approximately room temmperature and physically removing the inscription while the block is at approximately room temperature, said method of making the symbol or message reappear comprising the steps of heating the block so previously treated to approximately the temperature at which the symbol or message was enscribed, said heating continuing until the symbol or message reappears.
Claim 3
Dependent Claim
10 words
The method of claim 1 wherein the plastic is acrylic.
Claim 4
Dependent Claim
11 words
The method of claim 1 wherein the plastic is poly(methyl methacrylate)
Claim 5
Dependent Claim
56 words
An article comprising a tablet of plastic material with a latent image, which image was impressed by the simultaneous application of heat and pressure and which image has been physically removed at room temperature temporarily, such that when the block is reheated to the temperature used during the impressing of the image, the image will reappear.
Claim 6
Dependent Claim
56 words
An article comprising a tablet of plastic material with a latent image, which image was impressed by the simultaneous application of heat and pressure and which image has been physically removed at room temperature temporarily, such that when the block is reheated to the temperature used during the impressing of the image, the image will reappear.
Claim 7
Dependent Claim
11 words
The article of claim 4 wherein the plastic material is acrylic.
Claim 8
Dependent Claim
12 words
The article of claim 4 wherein the plastic material is poly(methyl methacrylate).
References Cited (Backward Citations)
US730823A
Cited
US2580305A
Cited
US2516727A
Cited
US2529151A
Cited
US3508344A
Cited
DE1924536A1
Cited
US3758649A
Cited
US4076772A
Cited
US4409277A
Cited
US4597814A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-10-26 | 1991-04-27 | 1991-10-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-10-26 | 1995-04-27 | 1995-10-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-10-26 | 1999-04-27 | 1999-10-27 | $7700.00 | Window Closed / Lapsed |