A new method of recording for tone reproduction was developed by application of the state of ink flight peculiar to the electrostatically extracted ink-jet method. In the state of ink flight in this new method, the ink forms a liquid thread from the nozzle tip, turns into ink corpuscles from the leading edge of the liquid thread, and then scatters like mist. The state of flight from a liquid thread to corpuscles is consecutive and continuous. For expressing tonal differences, the state around the leading edge of the liquid thread was used for recording the high-density area of the image and the state of scattering corpuscles for the low-density area. This differentiation in usage was confirmed workable and favorable results obtained.
Kazuhisa Matsuo, Toshimi Katayama, Takehiko Tomikawa, "A New Method for Recording Tone Images by Electrostatically Extracted Ink Jet" in Journal of Imaging Science and Technology, 1998, pp 228 - 233, https://doi.org/10.2352/J.ImagingSci.Technol.1998.42.3.art00007