New phthalide derivatives.

摘要

A new phthalide derivative useful as a colorless chromogenic material has the following formula:
<Chemistry id="chema01" num="0001"><Image id="ia01" he="40" wi="55" file="IMGA0001.TIF" imgContent="chem" imgFormat="TIFF" inline="no" /></Chemistry>wherein A is
<Chemistry id="chema02" num="0002"><Image id="ia02" he="30" wi="60" file="IMGA0002.TIF" imgContent="chem" imgFormat="TIFF" inline="no" /></Chemistry>R is an alkyl group having 1 to 4 carbon atoms or a propylene group which may form jullolidine ring together with the adjacent benzene ring, and n is 0 or an integer of 1 to 4 when
A is
<Chemistry id="chema03" num="0003"><Image id="ia03" he="31" wi="26" file="IMGA0003.TIF" imgContent="chem" imgFormat="TIFF" inline="no" /></Chemistry> but
m is an integer of 1 to 3 when A is
<Chemistry id="chema04" num="0004"><Image id="ia04" he="28" wi="16" file="IMGA0004.TIF" imgContent="chem" imgFormat="TIFF" inline="no" /></Chemistry>