Patent ID: 7541060
Filing Date: 2009-06-02
Classification: G02B,G09F,Y10T

Abstract:
1. A process for forming bichromal balls adapted for display applications at temperatures greater than 40° C., said process comprising: providing a polyethylene wax having a molecular weight distribution of about 200 to about 3000; providing an isoparaffin solvent; extracting said polyethylene wax with said isoparaffin solvent to remove a fraction of said polyethylene wax from a remaining purified portion of said polyethylene wax, said fraction having an average molecular weight of less than 700; and forming bichromal balls adapted for display applications at temperatures greater than 40° C. from said purified portion of said polyethylene wax, wherein said forming of the bichromal balls from said purified polyethylene wax includes: mixing said purified polyethylene wax with a first pigment to produce a first wax material; mixing said purified polyethylene wax with a second pigment to produce a second wax material; heating said first wax material to a temperature greater than the melting temperature of said first wax material; heating said second wax material to a temperature greater than the melting point of the second wax material; depositing said heated first wax material and said second wax material onto a spinning disk to produce bichromal balls adapted for use in display applications at temperatures greater than 40° C.