Water-dispellable hot melt polyester adhesives

Claim 1

A water-dispellable strong hot melt adhesive, resistant to degradation upon continued exposure to high temperatures and functional at high humidities, consisting essentially of a polyester resin which is normally solid at 20° C., has a ball-and-ring softening point greater than 35° C., fuses at a temperature between 35° C. and 200° C., has an intrinsic viscosity in the range of 0.1 - 1.0 and contains substantially equimolar amounts of the residue of a. 100 mole percent dicarboxylic acid molecules consisting essentially of 1. 0-95 mole percent aliphatic dicarboxylic acid having at least two carbon atoms between carboxyl groups and having an average of 4-10 carbon atoms, 2. 0-95 mole percent aromatic dicarboxylic acid, no more than 85 mole percent being terephthalic acid, and 3. 5-25 mole percent aromatic dicarboxylic acid in which magnesium sulfonate or an alkali metal sulfonate is attached to an aromatic ring; and b. 100 mole percent diol molecules consisting essentially of 1. 0-100 mole percent of a monoalkylene glycol containing 2 to 10 carbon atoms, 2. 0-100 mole percent polycaprolactonediol, and 3. 0-10 mole percent polyoxyalkylene glycol, the sum of the mole percentages of monoalkylene glycol residues and polycaprolactonediol residues being at least 90.