Chromogenic compounds and the use thereof as color former in copying or recording materials
Abstract
Abstract Novel chromogenic fluoran compounds of the formula: <IMAGE> wherein R1 is selected from the group consisting of alkyl radicals of from five to eight carbon atoms; R2 is selected from the group consisting of alkyl radicals of from one to eight carbon atoms; R3 is selected from the group consisting of hydrogen atom and lower alkyl radicals of from one to four carbon atoms; X1 and X2 are independently selected from the group consisting of hydrogen atom and lower alkyl radicals of from one to four carbon atoms, X3 is selected from the group consisting of hydrogen atom, lower alkyl radicals of from one to four carbon atoms, halogen atoms and trifluoromethyl radical; and n is an integer of a value of 1 or 2; providing that R1 does not represent an amyl radical when R2 is selected from the group consisting of alkyl radicals of from one to five carbon atoms, X1 and X2 are each a hydrogen atom, X3 is selected from the group consisting of hydrogen atom, lower alkyl radicals of from one to four carbon atoms and halogen atoms.
Inventors
- 👤 Hajime Kawai
- 👤 Katsuhiko Tsunemitsu
- 👤 Yoshiharu Fujino
- 👤 Yoji Shimizu
Bibliographic Details
Claims Analysis
Total Claims: 3References Cited (Backward Citations)
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