Patent · US Expired

Dry toner for direct electrostatic printing (DEP)

US5633110A · kind A · utility

8Cited by
4References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 7, 1995
Grant dateMay 27, 1997
Priority date
Expiry dateNov 7, 2015

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G9/0827
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A method for direct electrostatic printing (DEP) on an intermediate substrate or on a final substrate is provided, using a device that comprises a back electrode (105), a printhead structure (106) comprising a control electrode in combination with apertures (107), and a toner delivery means (101) presenting a cloud (104) of dry toner particles in the vicinity of said apertures (107), characterised in that (i) the toner particles have as topological criterium that the ratio of the length of the long axis of the projected microscopic image of said particles to the length of the short axis, is between 1.00 and 1.40 and (ii) the toner particles after addition of 0.5% by weight of fumed hydrophobic silica having a specific surface area of 260 m.sup.2 /g show a ratio of apparent density (.rho..sub.app) over real density (.rho..sub.real) ##EQU1##

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