The present invention comprises a polymeric epoxy patching resin containing metal intercalated AlSiO structures. The AlSiO structures are typically nanoclays, and the preferred metals are Cr, Sn and Zn, and mixtures thereof. The patching resin is applied to damaged mica tapes, where the metal intercalated nanoclays penetrate the damaged area, leaving a homogenous patch. The present invention may also be used to thicken an area of insulating tape.