Method of holding an ophthalmic lens blank

摘要

The present invention provides methods of holding ophthalmic lens blanks using thermoplastic lens blocking compositions. Preferred compositions either comprise a homopolymer or copolymer of epsilon-caprolactone, have a number average molecular weight between 3,000 and 100,000, or have a polydispersity less than 10. The composition may also comprise one or more modifiers, fillers or heat absorbing materials. In one method, the composition is injected into the cavity between a preformed lens block and a lens. In another method, the surface of a lens block comprising the thermoplastic lens blocking composition is heated and formed against the lens blank. Tapes that provide a receptive surface against which the composition may be adhered are disclosed.