摘要:
A disposable substrate of degradable material, such as a metal container, is provided with a photodegradable polymeric coating. The coating is water impermeable initially, but upon exposure to ultraviolet light degrades to become water permeable allowing water to contact and assist in degradation of the substrate. Suitable coatings are polymers containing side chain ketone groups, such as copolymers of vinyl monomers and vinyl ketones.