US 4,730,057 A · Phthalide derivatives useful as colorless chromogenic material

Abstract

A new phthalide derivative useful as a colorless chromogenic material has the following formula: ##STR1## wherein A and n have the same meaning as defined hereinbefore.

Claims1

Dependent claims

A phthalide derivative having the following formula:

##STR12## wherein n is an integer of 1 to 3.

Dependencies are inferred from the claim text.

Facts

Application

06/817,564Filed 10 Jan 1986

Priority

JP 60-707417 Jan 1985

Granted

8 Mar 1988

Term ends

Not estimatedThe source records don’t support an estimate.

Classification6 codes

C07D 307/88
Benzo [c] furans; Hydrogenated benzo [c] furans: with one oxygen atom directly attached in position 1 or 3
B41M 5/145
Organic colour formers, e.g. leuco dyes: with a lactone or lactam ring
B41M 5/327
Organic colour formers, e.g. leuco dyes: with a lactone or lactam ring
C07D 405/14
Heterocyclic compounds containing both one or more hetero rings having oxygen atoms as the only ring hetero atoms, and one or more rings having…:…

Abstract

A new phthalide derivative useful as a colorless chromogenic material has the following formula: ##STR1## wherein A and n have the same meaning as defined hereinbefore.

Phthalide derivatives useful as colorless chromogenic material

Life of this patent

Abstract

Claims1

Phthalide derivatives useful as colorless chromogenic material

Life of this patent

Abstract

Claims1