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US 2003/0146419 A1Published application
Photochromic naphthopyran compounds: compositions and articles containing those naphthopyran compounds
AssigneeVision-Ease Lens, Inc.
InventorXuzhi Qin
Life of this patent
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Abstract
A photochromic naphthopyran displays good color distribution when the naphthopyran has a central nucleus of the formula: 1 wherein F is a 5-member, 6-member, or 7-member heterocyclic ring group having only one heteroatom, the heteroatom selected from the group consisting of oxygen, sulfur, and nitrogen, the 2,3 or 3,2 positions of the heterocyclic ring fused to the g, h, or i side; R1 and R2 are the atoms or groups providing photochromic properties to the naphthopyran.
Claims20
A photochromic naphthopyran having a central nucleus of the formula:
- 31
- wherein F is a 5-member, 6-member, or 7-member heterocyclic ring group having only one heteroatom, the heteroatom selected from the group consisting of oxygen, sulfur, and nitrogen, the 2,3 or 3,2 positions of the heterocyclic ring fused to the g, h, or i side;
- R1 and R2 are the atoms or groups providing photochromic properties to the naphthopyran.
Dependencies are inferred from the claim text.