An apparatus for measuring the optical properties of photochromic spiropyrans, which are of importance in display and microimaging applications, is described. Step wedges are formed on the photochromic materials by means of rotating disk choppers. Step height readouts enable determinations of optical densities. Examples are given of the use of the apparatus in testing the writing sensitivity and erasability, at controlled temperatures, of solid dispersions of specific spiropyrans in polymeric binders.

Topics
Materials, Optical properties, Photochemical reactions, Chemical compounds
1.
R.
Heiligman‐Rim
,
Y.
Hirshberg
, and
E.
Fischer
,
J. Phys. Chem.
66
,
2465
(
1962
).
Google Scholar
Crossref
Search ADS
 
2.
P. L. Foris, U.S. Pat. No. 3,346,385, Oct. 10, 1967.
3.
Z. G.
Gardlund
,
Polymer Lett. (J. Polymer Sci., Part B)
,
6
,
57
(
1968
).
Google Scholar
Crossref
Search ADS
 
4.
G. I.
Lashkov
,
A. V.
Shablya
, and
D. N.
Glebovskii
,
Opt. Spectrosc.
20
,
95
(
1966
).
Google Scholar
 
5.
A. V.
Shablya
,
K. B.
Demidov
, and
Yu. N.
Polyakov
,
Opt. Spectrosc.
20
,
412
(
1966
).
Google Scholar
 
6.
G. W. Ewing, Instrumental Methods of Chemical Analysis (McGraw‐Hill Book Co., New York, 1954), pp. 125, 126.
7.
The PC material is an 11.8% dispersion, 45 μ thick, of 1, 3, 3‐trimethylindolino‐5′, 7′‐dichloro, 6′‐nitro‐benzospiropyran or ‐benzopyrylospiran (the colored form of which absorbs strongly at 470–603 nm) in the polymethacrylate, Acryloid B‐72 (Rohm and Haas).
8.
This PC material is a 24.8% dispersion, 15 μ thick, of 1, 3‐dimethyl, 3‐phenylindolino‐6′‐nitro‐benzospiropyran (the colored form of which absorbs strongly at 494–636 nm) in Acryloid B‐72.
This content is only available via PDF.
© 1969 The American Institute of Physics.
1969
The American Institute of Physics
You do not currently have access to this content.