step polyurethane adhesive composition of the first embodiment of the present invention are set forth below these additives include plasticizers useful for lowering the viscosity and increasing the elongation of the composition plasticizers useful in the formulation include phthalates such as dibutyl dioctyl dicyclohexyl diisooctyl diisodecyl dibenzyl or butylbenzylphthalate phosphates such as trioctylphosphate or diphenyloctylphosphate adipates such as dioctyladipate or benzyloctyladipate sulfonic acid esters sulfoneamides chloroparaffines and polybutenes dioctylterephthalate dotp is preferred carbon black is utilized as a filler and an additive for improving mechanical properties of the composition together with the non sag properties and uv stability thereof the preferred carbon black is one which conforms to astm n330 carbon black is utilized in an amount of from about 6 to about 24 weight percent based on the weight of the entire adhesive formulation and preferably from about 16 to about 20 weight percent another additive used is an isocyanate protecting agent which also acts as a diluent in the formulation and preferably is diethyl malonate the formulation further includes a moisture scavenger which can be any of those which are well known in the art other additives utilized include but are not limited to adhesion promoters fungicides uv stabilizers and the like all of which are well known.