Inkjet Cartridge Types (At Least From Xerox Perspective)
(From: Peter (hedgieus@yahoo.com).)
Here are history/trivia. (I used to work at Xerox marking technology group, working on ink-jets and daisy printers.)
Type 1 (or "push") ejects continuous stream (under pressure). The discovery goes back to Hertz (one who has the unit named after him) and theory is described in the book: The Theory of Sound, by John William Strutt, 3rd Baron Rayleigh.
Type 1 was commercialized first for printing postal labels and other similar applications. It was a big machine - 5x5x5 meters! Clumsy but fast. This was before laser printers. IBM published detailed (and definitive) research paper on this - circa 1985.
Type 2 (or pull) uses electrostatic field to extract the drop. It was never commercialized.
Type 3 (push-pull) or DOD is what we use in small printers now. Xerox put lot of money into developing this in the seventies, than (just when it achieved some 10 kHz (drops/second/nozzle) in the lab, (considered necessary minimum for viable printer) Japanese companies introduced first machines on the market. (I think first was NEC or Ricoh) and Xerox dropped the project. (Manufacturing people in Webster estimated that they can never produce it at profit, facing this competition.) Later, Xerox was using Sharp inkjet heads and printers, under Xerox label. Some research was then revived, (I suppose in cooperation with OEM supplier (Sharp).
