Patent ID: 7740734

Claim:
A curable epoxy composition comprising: an epoxy resin; a reagent selected from the group consisting of cationic compounds, compounds which are capable of forming cationic compounds, and mixtures thereof; and at least one compound with two aromatic centres and a central cyclic oxygen bridged ring, connecting the two aromatic centres according to formula I: wherein R 1 and R 2 are independently selected from the group consisting of hydrogen, a substituted alkyl group with a chain length of 1 to 20 carbon atoms, and an unsubstituted alkyl group with a chain length of 1 to 20 carbon atoms; R a to R h are independently selected from the group consisting of hydrogen, a substituted alkyl group, an unsubstituted alkyl group, a substituted aryl group, an unsubstituted aryl group, a substituted alkoxy group, an unsubstituted alkoxy group, halogen, and an additional aromatic ring formed by two adjacent R a to R h moieties; R 3 is selected from the group consisting of an alkyl bridge with 1-3 carbon atoms, an oxo-substituted alkyl bridge with 1-3 carbon atoms, and a direct bond between the oxygen and the adjacent aromatic ring; wherein R 3 can be said direct bond, so long as the central cyclic oxygen bridged ring contains at least 7 atoms; and R 4 is selected from the group consisting of: a substituted alkyl bridge with 1-3 carbon atoms, an unsubstituted alkyl bridge with 1-3 carbon atoms, an oxo-substituted alkyl bridge with 1-3 carbon atoms, oxygen, sulfur, oxidated sulfur (═SO, SO 2 ), nitrogen, nitrogen bonded to hydrogen, nitrogen bonded to a substituted alkyl group, nitrogen bonded to an unsubstituted alkyl group, nitrogen bonded to a substituted aryl group, nitrogen bonded to an unsubstituted aryl group, nitrogen bonded to a substituted alkoxy group, nitrogen bonded to an unsubstituted alkoxy group, and a direct bond between the two aromatic rings; wherein R 4 can be said direct bond, so long as the central cyclic oxygen bridged ring contains at least 7 atoms.