An
epoxy composition for applications such as one-part adhesives, coatings, prepreg and molding compounds that includes leuco dyes, particularly those comprising a N,N-dialkylamino-, N,N-diarylamino-, or cycloalkylamino-functional group on one of the aromatic rings, as a co-catalyst or co-curing agent. The use of the
leuco dye co-catalyst provides improved curing speed of the
epoxy composition comprising a latent curing agent / catalyst such as Novacure
imidazole microcapsules while maintaining the shelf-life stability. The
epoxy may also include a secondary co-catalyst that includes amides and lactams, particularly those comprising a N,N-dialkylamino-, N,N-diarylamino-, or dicycloalkylamino-functional group. Secondary cocatalysts of
low mobility at the storage conditions, such as those with a
long chain substitutent, dimeric or oligomeric amides or lactams, are particularly preferred. The improved epoxy composition is implemented as adhesives for manufacturing an
anisotropic conductive film (ACF) and also for connecting, encapsulating, or packaging of electronic devices.