Process of preparation of an aqueous gel ink with fixed color comprising silver nanoparticles
US12247131B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Aug 28, 2020 |
| Grant date | Mar 11, 2025 |
| Priority date | — |
| Expiry date | Apr 11, 2042 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB82Y30/00
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
The present invention concerns a process for preparing an aqueous gel ink with fixed color comprising the following steps: (i) preparing a gel-based matrix of aqueous ink; (ii) preparing an aqueous suspension of silver nanoparticles with a fixed color by mixing silver salts with: —water, —a mixture of at least an alkali metal or alkaline earth metal salt of citrate, —an oxidizing agent, preferably hydrogen peroxide H2O2, —and polyvinylpyrrolidone; (iii) adding under agitation the aqueous suspension of silver nanoparticles obtained in step (ii) to the gel-based matrix of aqueous ink obtained in step (i), to obtain an aqueous gel ink with fixed color with silver nanoparticles dispersed therein.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.