Binder resin for near-infrared absorbing film, and near-infrared absorbing filter using the same

The invention discloses a binder resin for near-infrared absorbing films, which exhibits good adhesion to a transparent film as the base, while stably containing a near-infrared absorbent. This binderresin itself is hard to be cured. Also disclosed is a near-infrared absorbing film using such a binder resin. The binder resin for near-infrared absorbing films is obtained by adding a near-infraredabsorbing dye (C) having an absorption maximum wavelength of 800-1200 nm to a resin composition containing 20-80% by mass of a (meth)acrylic polymer (A) having a Tg of from -65 DEG C to 20 DEG C and aweight average molecular weight of not more than 100,000 and 80-20% by mass of a (meth)acrylic polymer (B) having a Tg of from 50 DEG C to 180 DEG C. This binder resin for near-infrared absorbing films is characterized in that the polymer (A) contains a polymer (a) which has a crosslinkable functional group at two or more ends of the polymer chain.