Patent ID: 7293859
Filing Date: 2007-11-13
Classification: B41J

Abstract:
1. An ink jet recording head comprising: an element substrate having a main surface on which a discharge energy generating element for generating energy for discharging a liquid droplet is provided; a discharge port portion having a discharge port for discharging liquid at one end thereof, the discharge port being opposed to said discharge energy generating element; a supply path for supplying liquid to said discharge port portion; a first chamber communicating with said supply path, said first chamber having a rectangular bottom surface constituted by a portion of the main surface of said element substrate, wherein said discharge energy generating element is provided in said first chamber; and a second chamber having one end thereof communicating with said first chamber and another end thereof communicating with another end of said discharge port portion, said second chamber having a frustoconical shape; wherein a cross-sectional area of said first chamber, taken in a plane parallel to the main surface of said element substrate, is larger than a cross-sectional area of said second chamber, taken in a plane parallel to the main surface of said element substrate, and a cross-sectional area of said second chamber, taken in a plane parallel to the main surface of said element substrate, is larger than a cross-sectional area of said discharge port portion, taken in a plane parallel to the main surface of said element substrate, wherein said first chamber and said second chamber are connected through a first stepped portion provided at least at a side of said first chamber distant from a side of said first chamber at which said first chamber communicates with said supply path, and said second chamber and said discharge port portion are connected through a second stepped portion, each of said first stepped portion and said second stepped portion having a surface parallel to the main surface of said element substrate, wherein a side wall surface of said discharge port portion has a tapered shape with an inclination of 10 degrees or less with respect to a plane perpendicular to the main surface of said element substrate, and wherein a side wall surface of said second chamber is formed with an inclination of 10 to 45 degrees with respect to a plane perpendicular to the main surface of said element substrate.