Ink-jet print head and ink-jet printer

An ink-jet print head comprising:

• a liquid chamber into which a carrier liquid is filled;
• ink-jet driving means disposed within said liquid chamber, said driving means comprising a monomorph piezoelectric element;
• a nozzle communicated with said liquid chamber;
• a mixing unit disposed in the vicinity of said nozzle for mixing an ink to said carrier liquid;
• adjusting means for adjusting an amount with which said ink is mixed into said carrier liquid in said mixing unit, said adjusting means comprising an electroosmosis ink constant amount unit having a first porous membrane disposed within an ink tank which is filled with said ink;
• a first one-way valve that presents a back current of said ink disposed in an ink supply path which communicates said ink tank and said mixing unit;
• a second one-way valve provided between said liquid chamber and said mixing unit;
• a third one-way valve disposed at the entrance of said liquid chamber;
• and
• a plate having at least one small diameter hole disposed on a connection portion between said ink supplying path and said mixing unit.

An ink-jet printer comprising:

• a rotary drum around which a material to be printed is wrapped;
• a print head disposed movable in the axial direction said rotary drum;
• and
• driving means for moving said print head in the axial direction of said rotary drum in a ganged relation with a rotation of said rotary drum, said print head being an ink-jet print head comprising:
• a liquid chamber into which a carrier liquid is filled;
• ink-jet driving means disposed within said liquid chamber, said driving means comprising a monomorph piezoelectric element;
• a nozzle communicated with said liquid chamber;
• a mixing unit disposed in the vicinity of said nozzle for mixing an ink to said carrier liquid;
• adjusting means for adjusting an amount with which said ink is mixed into said carrier liquid in said mixing unit, said adjusting means comprising an electroosmosis ink constant amount unit having a first porous membrane disposed within an ink tank which is filled with said ink;
• a first one-way valve that presents a back current of said ink disposed in an ink supply path which communicates said ink tank and said mixing unit;
• a second one-way valve provided between said liquid chamber and said mixing unit;
• a third one-way valve disposed at the entrance of said liquid chamber;
• and
• a plate having at least one small diameter hole disposed on a connection portion between said ink supplying path and said mixing unit.