Crosslinkable adhesive composition comprising: a) from 40 to 60 wt% of at least one polyurethane obtainable by a polyaddition reaction: of at least one aromatic or aliphatic diisocyanate selected from the following diisocyanates, and mixture thereof: a1) isophorone diisocyanate, a2) 2,4-toluene diisocyanate, a3) diphenylmethane-2,4'-diisocyanate, a4) an allophanate derivative of hexamethylene diisocyanate of formula: in which: - p is an integer in the range from 1 to 2; - q is an integer in the range from 0 to 9; - R represents a hydrocarbon chain, saturated or unsaturated, cyclic or acyclic, linear or branched, comprising from 1 to 20 carbon atoms; - R 3 represents a divalent alkylene group, linear or branched, having from 2 to 4 carbon atoms; with at least one polyether diol, with or without the presence of at least one reaction catalyst, at a reaction temperature T1 below 95°C, in anhydrous conditions, and in amounts of diisocyanate(s) and of polyether diol(s) leading to an NCO/OH molar ratio, designated r 1, in the range from 1.6 to 1.9; b) from 39 to 59 wt% of at least one compatible tackifying resin, with a number-average molecular weight in the range from 200 Da to 5000 Da, and selected from the resins obtainable by one of the following methods: b1) polymerization of terpene hydrocarbons in the presence of Friedel-Crafts catalysts, followed by reaction with phenols, b2) polymerization of alpha-methylstyrene, followed by reaction with phenols; and c) from 0.01 to 1 wt% of at least one crosslinking catalyst, said percentages being expressed by weight relative to the total weight of the adhesive composition. a) from 40 to 60 wt% of at least one polyurethane obtainable by a polyaddition reaction: of at least one aromatic or aliphatic diisocyanate selected from the following diisocyanates, and mixture thereof: a1) isophorone diisocyanate, a2) 2,4-toluene diisocyanate, a3) diphenylmethane-2,4'-diisocyanate, a4) an allophanate derivative of hexamethylene diisocyanate of formula: in which: - p is an integer in the range from 1 to 2; - q is an integer in the range from 0 to 9; - R represents a hydrocarbon chain, saturated or unsaturated, cyclic or acyclic, linear or branched, comprising from 1 to 20 carbon atoms; - R 3 represents a divalent alkylene group, linear or branched, having from 2 to 4 carbon atoms; with at least one polyether diol, with or without the presence of at least one reaction catalyst, at a reaction temperature T1 below 95°C, in anhydrous conditions, and in amounts of diisocyanate(s) and of polyether diol(s) leading to an NCO/OH molar ratio, designated r 1, in the range from 1.6 to 1.9; a1) isophorone diisocyanate, a2) 2,4-toluene diisocyanate, a3) diphenylmethane-2,4'-diisocyanate, a4) an allophanate derivative of hexamethylene diisocyanate of formula: in which: - p is an integer in the range from 1 to 2; - q is an integer in the range from 0 to 9; - R represents a hydrocarbon chain, saturated or unsaturated, cyclic or acyclic, linear or branched, comprising from 1 to 20 carbon atoms; - R 3 represents a divalent alkylene group, linear or branched, having from 2 to 4 carbon atoms; with at least one polyether diol, with or without the presence of at least one reaction catalyst, at a reaction temperature T1 below 95°C, in anhydrous conditions, and in amounts of diisocyanate(s) and of polyether diol(s) leading to an NCO/OH molar ratio, designated r 1, in the range from 1.6 to 1.9; - p is an integer in the range from 1 to 2; - q is an integer in the range from 0 to 9; - R represents a hydrocarbon chain, saturated or unsaturated, cyclic or acyclic, linear or branched, comprising from 1 to 20 carbon atoms; - R 3 represents a divalent alkylene group, linear or branched, having from 2 to 4 carbon atoms; b) from 39 to 59 wt% of at least one compatible tackifying resin, with a number-average molecular weight in the range from 200 Da to 5000 Da, and selected from the resins obtainable by one of the following methods: b1) polymerization of terpene hydrocarbons in the presence of Friedel-Crafts catalysts, followed by reaction with phenols, b2) polymerization of alpha-methylstyrene, followed by reaction with phenols; and b1) polymerization of terpene hydrocarbons in the presence of Friedel-Crafts catalysts, followed by reaction with phenols, b2) polymerization of alpha-methylstyrene, followed by reaction with phenols; and c) from 0.01 to 1 wt% of at least one crosslinking catalyst, said percentages being expressed by weight relative to the total weight of the adhesive composition.