Flexible films comprise an adhesive layer and a fibrous supporting layer and the thermosetting adhesive materials which are non-tacky to the touch are storage stable at room temperature and can be cured at elevated temperature with a short cure time and can be cured to produce a tough flexible adhesive layer including bonding to oily surfaces, the materials are particularly useful in bonding together dissimilar substrates where they can reduce the formation of galvanic corrosion.