LENS BLANK BLOCKING ADHESIVE FILM

摘要

A conformable tape for bonding a lens block to ophthalmic lens blanks is provided. The tape comprises a polymeric backing and a pressure-sensitive adhesive. In a first preferred embodiment the surface of the backing is a blend of an olefin polymer with a polymer having acidic functionality. The blend may be formed as the backing layer, i.e., directly on the adhesive layer of the tape, or as the outer surface layer of a multilayered backing. In a second embodiment, the surface of the backing is a copolymer of an olefin monomer with a monomer having pendant acidic functionality. A lens block may be adhered to an ophthalmic lens blank by applying a section of the tape described above to an ophthalmic lens so that the pressure sensitive adhesive of the tape contacts the lens; conforming the tape to the compound surface of the lens; and attaching a lens block to at least a portion of the polymer backing layer. The tape may be made by extruding a polymeric backing material as described above; extruding a pressure-sensitive adhesive; and contacting the polymeric backing material and the pressure-sensitive adhesive. If desired, the polymeric backing material and the pressure sensitive adhesive may be coextruded to form the tape. In most preferred embodiments, the tape may be wound into a roll without a separate liner material.