Heat activatable adhesive compositions containing a crystal complex of a liquid plasticizer

Claim 1

A SOLID POTENTIALLY ADHESIVE COMPOSITION ACTIVATABLE TO ADHESIVENESS BY HEAT AND CAPABLE OF PROVIDING AN ADHESIVE BOND BETWEEN TWO MEMBERS, COMPRISING A POTENTIALLY VISCID NORMALLY SOLID THERMOPLASTIC POLYMERIC MATERIAL AND A LATENT PLASTICIZER COMPONENT UNIFORMLY DISTRIBUTED THROUGHOUT SAID POLYMERIC MATERIAL IN A PHASE PHYSICALLY DISTINCT FROM SAID POLYMERIC MATERIAL, SAID LATENT PLASTICIZER BEING A SOLID CRYSTAL COMPLEX INCLUSION COMPOUND CONSISTING OF A LIQUID PLASTICIZER FOR SAID POLYMERIC MATERIAL AND A CARRIER COMPOUND SELECTED FROM THE CLASS CONSISTING OF UREA AND THIOUREA, AT NORMAL CONDITIONS BEING STABLE AND EXHIBITING SUBSTANTIALLY NO PLASTICIZING CHARACTERISTICS BUT DISSOCIABLE AT AN ELEVATED TEMPERATURE TO RELEASE SAID LIQUID PLASTICIZER IN ACITVE CONDITION FOR PLASTICIZING SAID POLYMERIC MATERIAL, SAID LATENT PLASTICIZER COMPONENT BEING PRESENT IN AN AMOUNT EFFECTIVE TO PROVIDE AFTER HEATING A PLASTICIZED MIXTURE HAVING A SUBSEQUENT ADHESIVE TEMPERATURE AT LEAST 10*F. LOWER THAN THE INITIAL ADHESIVE TEMPERATURES OF SAID COMPOSITION BEFORE SUCH HEATING.