Curable photochromic compositions
AssigneeTransitions Optical, Inc.
InventorsMichael F. Haley, Linda K. Anderson, Anthony T. Gestrich, David B. Knowles, Stephen Robinson, Feng Wang, Elizabeth A. Zezinka
Life of this patent
Estimating the term…
Abstract
A curable photochromic composition can include: (a) a first component having a first compound with at least two active hydrogen-functional groups and an active hydrogen-functional group equivalent weight of at least 1000; (b) a second component having at least one of a polyisocyanate and a blocked polyisocyanate; and (c) at least one photochromic compound. The ratio of total isocyanate and blocked isocyanate group equivalents of the second component to total active hydrogen-functional group equivalents is at least 4:1.
Claims24
A curable photochromic composition comprising:
- (a) a first component comprising a first compound having at least two active hydrogen-functional groups and an active hydrogen-functional group equivalent weight of at least 1000, wherein said first compound comprises a polyol, and said polyol of said first compound is selected from polyether polyols, polyester polyols, polycarbonate polyols, and combinations thereof;
- (b) a second component comprising at least one of a polyisocyanate and a blocked polyisocyanate;
- and
- (c) at least one photochromic compound,
- wherein the ratio of total isocyanate and blocked isocyanate group equivalents of the second component to total active hydrogen-functional group equivalents is at least 4:1.
Dependencies are inferred from the claim text.