Patent ID: 7005482

Claim:
A self-supporting reactive hot-melt adhesive element comprising: a reactive one-component hot-melt adhesive which is solid at room-temperature, wherein said reactive one-component hot-melt adhesive comprises: (i) 0.5 to 30% w/w relative to the reactive hot-melt adhesive element of at least one free non-blocked isocyanate which is solid or liquid at room-temperature, said at least one isocyanate being selected from the group consisting of: (a) unsymmetrically substituted aliphatic and aromatic di- and polyisocyanates comprising isocyanate functions of different reactivity, and (b) a mixture of at least two isocyanates selected from the group consisting of aliphatic and aromatic di- and polyisocyanates which are solid or liquid at room temperature wherein at least one of said di- and polyisocyanates of said mixture is an unsymmetrically substituted di- or polyisocyanate comprising isocyanate functions of different reactivity; (ii) 20 to 90% w/w relative to the reactive hot-melt adhesive element of at least one isocyanate-reactive polymer and/or resin which is solid at room-temperature; and (iii) at least one non-isocyanate-reactive polymer, wax and/or resin wherein the maximum amount of said at least one non-isocyanate reactive polymer, wax and/or resin is 60% w/w relative to the reactive hot-melt adhesive element; wherein the content of free NCO-groups in said reactive hot-melt adhesive element is at least 0.5% w/w relative to the reactive hot-melt adhesive element; wherein said at least one non-isocyanate-reactive polymer, wax, and/or resin combines with said at least one isocyanate-reactive polymer and/or resin to form a matrix into which said at least one isocyanate is incorporated in homogenous distribution; and wherein the cross-linking of said self-supporting reactive hot-melt adhesive element takes place at temperatures of from 60° C. to 160° C.