| 摘要 |
<p>A near infrared ray absorption filter, particularly usable as a sharp cut filter for an infrared ray sensor, which comprises as an absorbent capable of controlling transmission of a ray at least one anthraquinone compound represented by the following formula,
<Chemistry id="chema01" num="0001"><Image id="ia01" he="25" wi="42" file="IMGA0001.TIF" imgContent="chem" imgFormat="TIFF" inline="no" /></Chemistry>wherein A<Sub>1</Sub>, A<Sub>2</Sub>, A3 and A4 are different from each other or the same, and stand for a phenyl or naphthyl group unsubstituted or substituted with at least one aklyl, alkoxy, phenoxy or hydroxy group, and the rings A and B are unsubstituted or substituted with at least one lower alkyl group or halogen atom.</p> |
