US 12,247,131 B2
Process of preparation of an aqueous gel ink with fixed color comprising silver nanoparticles
Olivier Albenge, Clichy (FR); Romain Metillon, Clichy (FR); Karine Mougin, Paris (FR); Feriel Ghellal, Clichy (FR); and Arnaud Spangenberg, Mulhouse (FR)
Assigned to SOCIETE BIC, Clichy (FR); UNIVERSITÉ DE HAUTE-ALSACE, Clichy (FR); and CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE, Paris (FR)
Appl. No. 17/630,805
Filed by SOCIETE BIC, Clichy (FR); UNIVERSITE DE HAUTE ALSACE, Mulhouse (FR); and CENTRE NATIONAL DE LA RECHERCHE SCIENTIFIQUE, Paris (FR)
PCT Filed Aug. 28, 2020, PCT No. PCT/EP2020/074154
§ 371(c)(1), (2) Date Jan. 27, 2022,
PCT Pub. No. WO2021/038085, PCT Pub. Date Mar. 4, 2021.
Claims priority of application No. 19306049 (EP), filed on Aug. 29, 2019.
Prior Publication US 2022/0275225 A1, Sep. 1, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. C09D 11/17 (2014.01); B82Y 30/00 (2011.01)
CPC C09D 11/17 (2013.01) [B82Y 30/00 (2013.01)] 19 Claims
 
1. 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, and an alkali metal hydride,
an oxidizing agent, and
and polyvinylpyrrolidone,
wherein the silver nanoparticles obtained in step (ii) are silver nanoparticles with the shape of spheres; and
(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.