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US 4,536,220 AGranted
Fluoran derivatives as new compounds and recording system utilizing the same as colorless chromogenic material
AssigneeKanzaki Paper Manufacturing Co., Ltd.
InventorsMitsuru Kondo, Hiroshi Iwasaki, Haruo Omura, Nobuo Kanda
Life of this patent
Estimating the term…
Abstract
A new fluoran derivative useful as a colorless chromogenic material has the following formula: ##STR1## wherein R, R.sub.1, R.sub.2, R.sub.3, X and Y have the same meaning as defined hereinbefore.
Claims8
A fluoran derivative, as a new article of a compound, having the following formula:
- ##STR8## wherein R is cyclopentyl, cycloheptyl, cyclohexylmethyl or cyclohexyl substituted by at least one alkyl and having 7 to 10 carbon atoms;
- R.sub.1 is an alkyl having 1 to 8 carbon atoms, R.sub.2 is hydrogen, R.sub.3 is a phenyl which may be substituted by at least one substituent selected from the group consisting of alkyls having 1 to 4 carbon atoms, halogen atoms and halogen substituted methyls, X is hydrogen and Y is hydrogen or an alkyl having 1 to 4 carbon atoms.
A recording system which utilizes a color forming reaction between a colorless chromogenic material and an electron accepting acidic reactant material, characterized in that said colorless chromogenic material comprises at least one fluoran derivative having the following formula:
- ##STR9## wherein R is cyclopentyl, cycloheptyl, cyclohexylmethyl or cyclohexyl substituted by at least one alkyl and having 7 to 10 carbon atoms;
- R.sub.1 is an alkyl having 1 to 8 carbon atoms, R.sub.2 is hydrogen, R.sub.3 is a phenyl which may be substituted by at least one substituent selected from the group consisting of alkyls having 1 to 4 carbon atoms, halogen atoms and halogen substituted methyls, X is hydrogen and Y is hydrogen or an alkyl having 1 to 4 carbon atoms.
Dependencies are inferred from the claim text.