Magnetically actuated ink jet printing device

A multicolor magnetically actuated ink jet printer, comprising:

• a plurality of ink jet printing devices, at least one for each of four colors of ink, each device having a substrate with at least one flexible membrane which serves as a diaphragm, an electrode for each diaphragm, a portion of which is aligned over and attached to the diaphragm, a nozzle plate bonded to the substrate with a cavity for each diaphragm and open thereto, the cavity containing a nozzle aligned above the diaphragm and an ink inlet, and at least one magnetic field generating means for generating a magnetic field of predetermined strength and direction;
• a carriage on which each of the printing devices are mounted for translation thereby and therewith;
• means to translate the carriage;
• four separate, different colored ink supplies connected to the ink inlets of the cavity of each printing device to fill the cavities with a different one of the four colors of inks in said ink supplies;
• and
• means to selectively apply electric current to each of the electrodes.

A method of fabricating a magnetically actuated ink jet printing device, comprising the steps of:

• (a) providing a planar substrate having first and second parallel surfaces;
• (b) forming an array of metal electrodes on the substrate first surface, each electrode having an input terminal and an output terminal;
• (c) passivating the electrodes;
• (d) depositing a sacrificial layer of material on the substrate first surface and over the passivated electrodes;
• (e) patterning the sacrificial layer to form a shape of an ink cavity on the substrate first surface for each electrode;
• (f) depositing a layer of nozzle plate material on the substrate first surface and over the patterned sacrificial layer;
• (g) forming a flexible membrane in the substrate for each electrode, the membranes having predetermined dimension and location, so that a portion of each electrode resides on each membrane;
• (h) patterning the nozzle plate material to form a nozzle plate having a nozzle for each membrane and to remove the nozzle plate material from the electrode terminals;
• (i) removing the sacrificial layer to form the ink cavities;
• and
• (j) mounting a magnetic field generating means adjacent at least one side of the substrate, so that a magnetic field generated thereby has a field direction perpendicular to the electrode portions residing on said membranes.

A magnetically actuated ink jet printing device for use in an ink jet printer, comprising:

• a substrate having at least one flexible diaphragm therein;
• at least one electrode formed on the substrate, a portion of the at least one electrode being overlying and attached to the at least one diaphragm;
• a member formed on a surface of the substrate and having at least one internal cavity opening against the substrate surface which forms a part thereof, the cavity serving as an ink reservoir, said cavity having a nozzle and an ink inlet, the nozzle being aligned with the diaphragm;
• at least one magnetic field generating means being located adjacent the substrate and oriented to generate a magnetic field of a predetermined strength and direction relative to the electrode over the diaphragm;
• an ink supply connected to the ink inlet of the cavity to fill said cavity with ink;
• and
• means for selectively applying electrical current to the at least one electrode, the current through the electrode which is in the magnetic field producing a force which causes the diaphragm with the electrode to deform momentarily in a direction at least one of toward and away from the nozzle, each momentary deformation of the diaphragm and electrode ejecting an ink droplet from the nozzle.