Share Email Print

Proceedings Paper

Photoerasing paper and thermocoloring film
Author(s): Sebastian V. Kanakkanatt
Format Member Price Non-Member Price
PDF $17.00 $21.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

Thermal coloration of spiropyrans and spiroxazines at or above their melting point is well known to photochromists. The erasure of the color developed by exposure of photochromic paper by radiations of certain wavelengths in the visible region is little known. Six-nitrospirobenzopyran and 8- nitrospirobenzopyran, 8-methoxy-6-nitrospirobenzo-pyran, 6- methoxy-8-nitrospirobenzopyran, and 6,8-dinitrospirobenzopyran have been studied. The medium in which these photochromic dyes were dissolved or incorporated was limited to cellulose derivatives such as cellulose acetate, cellulose acetate- butyrate, and cellulose trinitrate. Paper coated with 6- nitrospirobenzopyran dissolved in an ethyl acetate solution of cellulose trinitrate readily colored on exposure to UV light or IR radiation and faded on exposure to light in the visible range. This unusual phenomenon, although not fully understood, is believed to be a selective light sensitizing ability of nitro groups. The applications of photoerasing paper and thermally colorable films are numerous, such as in polaroid type photography, in copy machines, and in thermally stable photochromic ophthalmic lenses.

Paper Details

Date Published: 4 August 1997
PDF: 7 pages
Proc. SPIE 3227, Interactive Paper, (4 August 1997); doi: 10.1117/12.280771
Show Author Affiliations
Sebastian V. Kanakkanatt, Univ. of Akron (United States)

Published in SPIE Proceedings Vol. 3227:
Interactive Paper
Graham G. Allan; Jean J. Robillard, Editor(s)

© SPIE. Terms of Use
Back to Top