Formaldehyde-naphthalene-phenol copolymer Formaldehyde-naphthalene-phenol polymer Formaldehyde-phenol-naphthalene copolymer Formaldehyde, polymer with naphthalene and phenol Naphthalene-formaldehyde-phenol copolymers Naphthalene-formaldehyde-phenol polymers Naphthalene-phenol-formaldehyde copolymer Naphthalene, polymer with formaldehyde and phenol Phenol-formaldehyde-naphthalene copolymer Phenol, polymer with formaldehyde and naphthalene