Ink jet recording head with extended electrothermal conversion element life and method of manufacturing the same

An ink jet recording head, comprising:

• a plurality of ink discharge ports for discharging ink;
• a plurality of electrothermal converting elements that are provided to be associated with each of said ink discharge ports, respectively, for bubbling and discharging the ink;
• a plurality of pressure chambers for containing said electrothermal converting elements and providing spaces for heating and bubbling said ink;
• a common liquid chamber for supplying ink to said plurality of pressure chambers;
• and
• a plurality of ink flow paths for respectively communicating said pressure chambers with said common liquid chamber,
• wherein said ink flow paths are arranged such that central lines of said ink flow paths in a direction of ink supply to said pressure chambers at boundary portions between said ink flow paths and said pressure chambers are positioned offset from central lines of said electrothermal converting elements extending in the same direction,
• wherein the offset directions of said ink flow paths from the central lines of said electrothermal converting elements are the same for said plurality of ink flow paths arranged in one row, and
• wherein said ink flow paths are formed in two opposing rows side by side on both sides of said common liquid chamber, and
• wherein the offset directions of each of said ink flow paths from the central line of each of said electrothermal converting elements for said opposing ink flow path rows are symmetrical with respect to a line parallel with a row direction of said opposing ink flow path rows.

An ink jet recording head, comprising:

• a plurality of ink discharge ports for discharging ink;
• a plurality of electrothermal converting elements that are provided to be associated with each of said ink discharge ports, respectively, for bubbling and discharging the ink;
• a plurality of pressure chambers for containing said electrothermal converting elements and providing spaces for heating and bubbling said ink;
• a common liquid chamber for supplying ink to said plurality of pressure chambers;
• and
• a plurality of ink flow paths for respectively communicating said pressure chambers with said common liquid chamber,
• wherein said ink flow paths are arranged such that central lines of said ink flow paths in a direction of ink supply to said pressure chambers at boundary portions between said ink flow paths and said pressure chambers are positioned offset from central lines of said electrothermal converting elements extending in the same direction, and
• wherein side walls of said pressure chambers facing said ink flow paths have no acute corner.

An ink jet recording head, comprising:

• a plurality of ink discharge ports for discharging ink;
• a plurality of electrothermal converting elements that are provided to be associated with each of said ink discharge ports, respectively, for bubbling and discharging the ink;
• a plurality of pressure chambers for containing said electrothermal converting elements and providing spaces for heating and bubbling said ink;
• a common liquid chamber for supplying ink to said plurality of pressure chambers;
• and
• a plurality of ink flow paths for respectively communicating said pressure chambers with said common liquid chamber,
• wherein said ink flow paths are arranged such that central lines of said ink flow paths in a direction of ink supply to said pressure chambers at boundary portions between said ink flow paths and said pressure chambers are positioned offset from central lines of said electrothermal converting elements extending in the same direction, and
• wherein ink flows into said pressure chambers from respective single entrances.