Adhesive-coated sheet material

Claim 1

A SHEET BACKING PROVIDED AT LEAST ONE MAJOR SURFACE WITH A TACKY, HEAT-HARDENABLE, SUBSTANTIALLY SOLVENTFREE, COLD FLOW-RESISTANT, COHERENT LAYER WHICH ESSENTIALLY COMPRISES A STORABLE UNIFORM BLEND OF POLYMERS WHICH ARE MUTUALLY SOLUBLE AT 300* F., CONSISTING ESSENTIALLY OF: ONE PART OF A SUBSTANTIALLY ENTIRELY CURABLE THERMOSETTING RESIN SYSTE HAVING AN EPOXY EQUIVALENT OF NOT MORE THAN ABOUT 1200 AND A SOFTENING POINT OF LESS THAN 100* C., SAID RESIN SYSTEM ESSENTIALLY COMPRISING AT LEAST ABOUT ONE-HALF PART REACTIVE EPOXY RESIN POURABLE AT ROOM TEMPERATURE, AND MEANS FOR CURING ALL ESIN IN SAID SYSTEM, AND FROM ABOUT 1/4 PART TO ABOUT 2 1/2 PARTS, CONSTITUTING SUBSTANTIALLY ALL THE REMAINDER OF SAID BLEND, OF A RUBBERY BUTADIENE: ACRYLONITRILE COPOLYMER SYSTME PRESENT IN AMOUNT SUCH AS TO RENDER SAID BLEND WHEN FORMED PER SE IN A 3-MIL LAYER, TACKY, FLEXIBLE AND SELF-SUSTAINING, POSSESSED OF AN INTERNAL STRENGTH VALUE OF AT LEAST ABOUT 5 MINUTES, RETENTIVE OF AN AFFINITY FOR THE SURFACE OF A SMOOTH ORIENTED POLYESTER FILM EQUAL TO AT LEAST ABOUT ONE-HALF LB. PER HALF INCH OF WIDTH, WHEN MEASURED AFTER STORAGE AT 40* F. FOR SIX MONTHS, AND CAPABLE OF DISPLAYING A TENSILE SHEAR VALUE OF AT LEAST 1000 P.S.I. AFTER CURE.