PROCESS FOR PRODUCING NEAR-INFRARED-ABSORBING COMPOUND, NEAR-INFRARED-ABSORBING COMPOSITION, NEAR-INFRARED CUT FILTER, SOLID PHOTOGRAPHING ELEMENT, AND PURIFICATION METHOD

摘要

Provided are a process for producing a near-infrared-absorbing compound which makes it possible to form a near-infrared cut filter having excellent heat resistance, a near-infrared-absorbing composition, a near-infrared cut filter, a solid photographing element, and a purification method. The process for producing a near-infrared-absorbing compound comprises a step in which a solution containing a coordination-site-containing polymer (A1) and/or a compound obtained by the reaction of the coordination-site-containing polymer (A1) with a metallic ingredient is purified using a porous separation material.