Encapsulated dispersions comprising electrophoretically mobile organic colorants

US8270063B2 · kind B2 · utility

Assignee

• BASF SE

Inventors

• Margherita Fontana · Basel, CH
• Gerardus De Keyzer · Riehen, CH
• Philippe Bugnon · Le Mouret, CH
• Marcel Hahn · Magden, CH
• Kishor Kumar Mistry · Heysham, GB
• Clemens Auschra · Glückstadt, DE

Key dates

• Filing date: Aug 28, 2008
• Grant date: Sep 18, 2012
• Expiry date: Jun 18, 2029

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C09B67/006
• WIPO field: Basic materials chemistry
• WIPO sector: Chemistry

Abstract

The invention relates to an electrophoretic display, comprising electrodes and cells containing at least one kind of ionic, monochrome particles, a non-polar liquid and a dispersant, wherein the ionic, monochrome particles of at least one kind are essentially aggregates consisting of a carbon containing pigment and a cationic pigment orcationic pigment derivative, and the dispersantis selected from the group consisting of polyacrylates, polyesters, polyurethanes and copolymers, with the proviso that the cationic pigment or cationic pigment derivative is not a reaction product of carbonblack with diazotated procaine hydrochloride. In general, the whole quantity of the pigment and the main part, preferably at least 80%, most preferred from 95% to 100%, of the whole cationic pigment or cationic pigment derivative present within the cells is comprised in the aggregates, with essentially no pigment and only a minor part of the cationic pigment or cationic pigment derivative physically distinct from the aggregates.