Patent number: 4996328
Abstract: Novel bis-(indolyl)ethylenes, process for their production and record systems utilizing such bis-(indolyl)ethylene chromogens are described.Bis-(indolyl)ethylenes of the following general formula are prepared: ##STR1## wherein each L.sup.1 and L.sup.2 is the same or different and is each independently selected from indole moieties (J1) through (J4) (L.sup.1 need not be the same as L.sup.2), ##STR2## wherein in (J1) through (J4) above, each of R.sup.5, R.sup.6, R.sup.13, R.sup.14, R.sup.21, R.sup.22, R.sup.29 and R.sup.30 need not be the same and is each independently selected from hydrogen, alkyl (C.sub.1 -C.sub.8), cycloalkyl, alkylaroxy, alkylalkoxy, and substituted or unsubstituted aryl, such as phenyl, naphthyl, or heterocyclyl.Each of R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.7, R.sup.8, R.sup.9, R.sup.10, R.sup.11, R.sup.12, R.sup.15, R.sup.16, R.sup.17, R.sup.18, R.sup.19, R.sup.20, R.sup.23, R.sup.24, R.sup.25, Rphu 26, R.sup.27, and R.sup.
Type:
Grant
Filed:
March 8, 1989
Date of Patent:
February 26, 1991
Assignee:
Appleton Papers Inc.
Inventor:
Ponnampalam Mathiaparanam