Preparation of core-shell type cerium oxide/polymer hybrid nanoparticles for ink-jet printing

Recently, it has been reported that the spherical core-shell type cerium oxide/polymer hybrid nanoparticles which has a good dispersibility for water or alcohol can be obtained by using cerium nitrate hexahydrate and polyvinylpyrrolidone as source materials in the polyol method. This article presents 1) examination concerning raw materials for synthesis of the core-shell type nanoparticles, 2) flow properties of a dispersion sol of the core-shell type nanoparticles, and 3) experiment of ink-jet printing of the dispersion sol as an ink. First, we investigated whether the core-shell type nanoparticles were able to be obtained by using cerium (IV) ammonium nitrate instead of cerium (III) nitrate hexahydrate or hydroxypropyl cellulose instead of polyvinylpyrrolidone in the synthesis. As a result, in the case of using cerium (IV) ammonium nitrate, the spherical core-shell type nanoparticles were not able to be obtained. However, in the case of using hydroxypropyl cellulose, the core-shell type nanoparticles similar to the reported nanoparticles were able to be obtained. Therefore, it became clear that the synthesis condition for obtaining the core-shell type nanoparticles was not limited to using polyvinylpyrrolidone as a polymer. Next we investigated the flow properties of dispersion sols of the core-shell type nanoparticles synthesized by using cerium (III) nitrate hexahydrate and polyvinylpyrrolidone as starting materials. In the case of the dispersion sol with 4.3 vol% nanoparti-cle concentration using a mixing solution of water and ethylene glycol as a dispersion medium, the viscosity and surface tension were 5 mPafis and 55 mN/m, respectively. Finally, it also became clear that the dispersion sols were able to be used for the ink-jet process for making patterns.