Process for obtaining a photochromic latex
US6770710B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 16, 2001 |
| Grant date | Aug 3, 2004 |
| Priority date | — |
| Expiry date | Nov 16, 2021 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F2/44
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
The process comprises:(1) the preparation of a mixture comprising at least one organic monomer Z with a C═C group, polymerizable by a radical process, at least one organic photochromic compound, at least one surfactant, water and optionally a polymerization primer;(2) the treatment of the mixture obtained in step (1) in order to form a miniemulsion consisting of an organic phase dispersed in the form of droplets having a diameter of 50 to 500 nm, and preferably 50 to 300 nm, in an aqueous phase;(3) the addition to the miniemulsion of a polymerization primer, if this latter was not introduced in step (1), or of a quantity of primer additional to that added in step (1);(4) the polymerization of the reaction mixture obtained in step (3), and(5) the recovery of the photochromic latex.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.