Abstract: The object is to provide a writing instrument in which a large-diametric ink retaining portion with narrow grooves in width and still capable of securing a large enough air channel can be formed so that the replacement of the sufficient amount of air can be effected between the ink retaining portion and the outside air. To achieve this, in an ink retaining portion (12), a plurality of cutouts (32) are formed so that each cutout (32) is formed to a right angle direction with respect to a center line (16a) of the sheet element (16) with a length equal to or greater than half the radius (R) (A≧(R/2), B≧(R/2)) and that one end of the cutout (32) is extended to the periphery.

Abstract: A feeding duct for writing liquid in fountain pen nibs and method of producing same, wherein the duct includes a substantially cylindrical element having multiple circumferential grooves creating respective fins, of a support for a nib and a connecting mans to an ink reservoir the feeding duct is produced in two distinct portions disposed symmetrically in relation to a longitudinal plane each portion is provided with a longitudinal recess extending along the entire length of the portion, apart from the front end thereof, and is combined with recess of the other portion to form a groove when the two portions are secured one to another.

Abstract: A longitudinal groove which allows a number of annular grooves formed on the outer peripheral surface of an ink storage body to communicate with an ink chamber is cut halfway into the thickness of a flange formed at the rear part of the ink storage body. An outer part of the longitudinal groove cut into the flange is made to communicate with a passage which is defined by a cutout formed on the periphery of the flange and the inner wall of the barrel cylinder so that this passage establishes communication between the longitudinal groove and the ink chamber.