Specific preferred secondary acid generators of Formula VI are those in which R15 is a methyl group, L1 is a hydroxyl group and L2 is a p-methylphenylsulfonyl, p-n-butylphenylsulfonyl, p-n-octylphenylsulfonyl group, (7,7-dimethyl-bicyclo 2.2.1 !heptan-2-onyl)methylsulfonyl or N,N-dimethylsulfamate group.