| abstract |
Thermoplastic polyurethane compositions having excellent mechanical and thermal properties, high hardness and the capabilty of binding or adhering to magnetic pigments, formed by reacting 1,4-cyclohexanedimethanol with a dicarboxylic acid such as adipic, azelaic or 1,12-dodecanedioic acid, or mixtures thereof in a hydroxyl number range of from about 50 to about 250 to form a hydroxyl-terminated polyester, combining the polyester so formed with a chain extender to form a mixture in a hydroxyl number range of from about 130 to about 300 and reacting said mixture with a diisocyanate to form the polyurethane resin. Such polyurethanes display excellent binding properties for adhering magnetic iron oxide or other magnetic pigments to flexible substrates to form magnetic tape. |