C09B23/162

INFRARED CUT-OFF FILTER, SOLID-STATE IMAGE SENSOR FILTER, SOLID-STATE IMAGE SENSOR, AND METHOD FOR PRODUCING SOLID-STATE IMAGE SENSOR FILTER

An infrared cut-off filter including a cyanine dye including a tris(pentafluoroethyl) trifluorophosphate anion and a cation having a polymethine and a nitrogen-containing heterocycle located at each end of the polymethine, and an acrylic polymer having a unit structure of formula (1).