Patent · US Expired

Methods of surface modification for improving electrophoretic display performance

US6870662B2 · kind B2 · utility

19Cited by
18References
63Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 2, 2003
Grant dateMar 22, 2005
Priority date
Expiry dateJun 10, 2023

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/24562
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

The present invention is directed to methods for improving the performance of an electrophoretic display by modifying the display cell surface. More specifically, the methods are directed to modification of the microcup surface after the microcups are released from the mold. The microcups which have undergone any of the treatment methods of the invention show significant improvement in their surface properties, such as chemical functionality, surface roughness, surface tension, morphology, surface charge, surface reflectivity, surface conductivity and optical properties, particularly optical density in the visible light region. An electrophoretic display formed from the treated microcups has many advantages. For example, the display shows a higher contrast ratio, lower electro-optic response time, lower driving voltage, longer shelf life, higher imageincreasing bistability and higher threshold voltage. In addition, it exhibits an improved image quality by reducing undesirable scum formation or irreversible particle deposition on the microcup surface.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.