Abstract: Disclosed herein are heat-activatable adhesive compositions comprising an amorphous condensation polymer which is characterized by having an acid component comprising a phthalic acid derivative and a glycol component comprising from about 15 to about 85 mole percent of (1) a linear aliphatic glycol having the structure HO--R--H wherein R is either: ##STR1## or --CH.sub.2 CH.sub.2 O--.sub.n wherein n is an integer from 2 to 4; and from about 85 to about 15 mole percent of (2) a branched aliphatic glycol having the structure: ##STR2## wherein R.sup.1 and R.sup.2 are alkyl. These polyester adhesives are further characterized as being soluble in halogenated solvents, having glass transition temperatures within the range of about -30.degree. to about 50.degree. C, and having high bonding strengths at elevated temperatures. They have been found useful in a variety of photographic materials, and particulary in photographic film units.