Novel sterically hindered amine light stabilizers

The instant invention pertains to sterically hjndered amine Nght stabilizers (HALS) with low basicity at the nitrogen atom and high thermal stability. They are characterized by their spiro- substitution in the 4-position of the tetramethylpiperidine ring (Spiro-NOR-HALS). These compounds are particularly effective in stabilizing polymers, especially thermoplastic polyolefins, against the deleterious effects of oxidative, thermal and actinic radiation. The compounds are also particularly effective in stabilizing acid catalyzed and ambient cured coatings systems. They are particularly useful when high processing temperatures are additional required.