Most, if not all, commercial adhesion systems are proprietary
products and their actual compositions are well kept secrets by the manufacturers and therefore not well
known by the users. Nevertheless, patent literature and
numerous articles written during the last 40 years make
it possible, at least in a qualitative sense, to draw some
conclusions about the composition of the most frequently
used primers and adhesives. From this information it can,
in a general sense, be concluded that both the primers
and the adhesives are ‘rubbery’ materials which can be
heat cured.