Abstract: Adhesives containing some bifunctional and some at least trifunctional epoxide compounds, photoinitiators, and acrylates of methacrylates corresponding to general formulaCH.sub.2 =C(R.sup.1)-CO-(OC.sub.m H.sub.2m).sub.n -OR.sup.2in which R.sup.1 is hydrogen or methyl and R.sup.2 is a hydrocarbon radical containing a cationically cleavable oxacycloalkyl or oxacycloalkenyl group, continue to harden in darkness after their hardening has been photoinitiated, and thus can produce strong bonds between opaque substrates, when the substrates are coated with the adhesives, the adhesive coatings are exposed to light to initiate the hardening, and the coated substrates are pressed together within a short interval before the hardening of the photoinitiated adhesives advances to the gel point.

Abstract: Monomer compositions crosslinkable by photoinitiators and stabilizers and containing liquid polymerizable monomers having one or more ethylenic double bonds, camphor quinone, an aryl sulfinate, thickeners, and, optionally, adhesion promoters and/or accelerators as photoinitiated adhesives hardening in darkness for the bonding of non-transparent surfaces. Bonds having excellent tensile shear strengths are obtained.

Abstract: The invention relates to an .alpha.-cyanoacylate adhesive which is fluorescent in ultraviolet light.