Stable IR dye composition for invisible marking
US6706460B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 20, 2002 |
| Grant date | Mar 16, 2004 |
| Priority date | — |
| Expiry date | Nov 20, 2022 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41M3/144
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
This invention relates to a latex composition comprising water as a continuous phase and, as the dispersed phase, hydrophobic polymer particles having associated therewith an infrared polymethine dye having covalently bonded thereto a phenylenediamine moiety. It further relates to a process for associating dye with polymer particles in a latex composition comprising the steps of:(1) forming a dye solution by dissolving a polymethine dye having covalently bonded thereto a phenylenediamine moiety in a water miscible or immiscible organic solvent;(2) forming a latex by dispersing hydrophobic polymer particles in an aqueous continuous phase;(3) blending the latex with the dye solution; and(4) loading of the polymer particles by removing the organic solvent, thereby forming a latex having the polymethine dye associated therewith.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.