Misdirection in Multinozzle Ink-Jet Arrays

One of the factors affecting print quality in ink-jet matrix printing systems is how accurately drops are placed within the matrix. One source of inaccurate drop placement is misdirection of the ink-jet streams. This report discusses techniques for the measurement, analysis, and interpretation of misdirection of ink-jet streams. These techniques are used to separate macroscale and microscale misdirection effects in glass capillary multinozzle ink-jet arrays. The effects of nozzle length, operating frequency, drop velocity, ink viscosity, and nozzle diameter are examined. A minimum mass flow must be exceeded so that an array will operate with minimum stream misdirection, hence the mass-flow rate of ink through the nozzles is a governing parameter for misdirection.