Claims
- 1. A the process of forming a permanent yellow image on a film having a transparent film base and an imaging layer of colorless 10,12-docosadiyndioic acid having the formula ##STR3## which comprises scribing said film with a source of ultraviolet radiation at a relatively short wavelength of between about 200 and 350 nm to induce a photochromic change in the exposed areas to a blue image imposed on a colorless background, exposing said blue image to laser emissions at a longer wavelength of at least 450 nm to induce a thermochromic change in the blue image to a permanent yellow image imposed on the colorless background.
- 2. The process of claim 1 wherein said ultraviolet radiation writing device is an electron beam or a UV laser.
- 3. The process of claim 1 wherein said UV light at a short wavelength is transmitted by a UV laser device in a dual laser imaging process.
Parent Case Info
This is a division of application Ser. No. 601,534, filed Oct. 23, 1990, now U.S. Pat. No. 5,139,926.
US Referenced Citations (3)
Divisions (1)
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Number |
Date |
Country |
Parent |
601534 |
Oct 1990 |
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