A twisting ball display sheet is disclosed which utilizes a mechanism other than Zeta potential to create dipole moment to rotate a plurality of bichromal balls. The twisting ball display sheet comprises a transparent sheet which contains a plurality of bichromal balls. Each bichromal ball comprises...http://www.google.es/patents/US5900858?utm_source=gb-gplus-sharePatente US5900858 - Rotation mechanism for bichromal balls of a twisting ball display sheet based on contact potential charging
Rotation mechanism for bichromal balls of a twisting ball display sheet ...
