A curable epoxy resin composition comprising: (a) at least one epoxy resin comprising, based on the total epoxy resin weight, at least 50 wt% of an epoxy resin comprising one or more diglycidyl ethers of bisphenol A or diglycidyl ethers of bromobisphenol A; oligomeric or polymeric diglycidyl ethers of bisphenol A; oligomeric or polymeric diglycidyl ethers of tetrabromobisphenol A; diglycidyl ethers of bisphenol F or their derivatives; epoxy novolac resins; epoxy cresol novolac resins; or mixtures thereof; (b) a curing agent selected from a polyoxypropylenediamine; isophorondiamine; 1,3-cyclohexanebis(methylamine); 4,4'-methylenebis(cyclohexylamine); 1,2-diaminocyclohexane; 4,4'-diaminodicyclohexylmethane; nadic acid anhydride; methyl nadic acid anhydride; copolymers of styrene and maleic acid anhydrides; methyltetrahydrophthalic anhydride; methylhexahydrophthalic anhydride; methyl-(endo)-5-norbornene-2,3-dicarboxylic anhydride; hexahydrophthalic anhydride; tetrahydrophthalic anhydride; pyromellitic dianhydride; ciscyclopentanetetracarboxylic acid dianhydride; hemimellitic anhydride; trimellitic anhydride; naphthalene-1,8-dicarboxylic acid anhydride; phthalic anhydride; dichloromaleic anhydride; dodecenylsuccinic anhydride; glutaric anhydride; maleic anhydride; succinic anhydride; or mixtures thereof; and (c) a carboxylic acid group containing reaction product of (i) a carboxylic acid or its anhydride compound, and (ii) an amphiphilic block copolymer having at least one anhydride-reactive group, at least one epoxy resin miscible block segment, and at least one epoxy resin immiscible block segment; wherein the curable epoxy resin composition upon curing has a clarity value of at least 30% as measured by a BYK haze-gard dual haze meter. (a) at least one epoxy resin comprising, based on the total epoxy resin weight, at least 50 wt% of an epoxy resin comprising one or more diglycidyl ethers of bisphenol A or diglycidyl ethers of bromobisphenol A; oligomeric or polymeric diglycidyl ethers of bisphenol A; oligomeric or polymeric diglycidyl ethers of tetrabromobisphenol A; diglycidyl ethers of bisphenol F or their derivatives; epoxy novolac resins; epoxy cresol novolac resins; or mixtures thereof; (b) a curing agent selected from a polyoxypropylenediamine; isophorondiamine; 1,3-cyclohexanebis(methylamine); 4,4'-methylenebis(cyclohexylamine); 1,2-diaminocyclohexane; 4,4'-diaminodicyclohexylmethane; nadic acid anhydride; methyl nadic acid anhydride; copolymers of styrene and maleic acid anhydrides; methyltetrahydrophthalic anhydride; methylhexahydrophthalic anhydride; methyl-(endo)-5-norbornene-2,3-dicarboxylic anhydride; hexahydrophthalic anhydride; tetrahydrophthalic anhydride; pyromellitic dianhydride; ciscyclopentanetetracarboxylic acid dianhydride; hemimellitic anhydride; trimellitic anhydride; naphthalene-1,8-dicarboxylic acid anhydride; phthalic anhydride; dichloromaleic anhydride; dodecenylsuccinic anhydride; glutaric anhydride; maleic anhydride; succinic anhydride; or mixtures thereof; and (c) a carboxylic acid group containing reaction product of (i) a carboxylic acid or its anhydride compound, and (ii) an amphiphilic block copolymer having at least one anhydride-reactive group, at least one epoxy resin miscible block segment, and at least one epoxy resin immiscible block segment;