Mitsubishi Pencil Kabushiki Kaisha

Yoshiomi Konose

Kazuhiko Takanashi

Takao Koyama

A writing implement having a feeder core for feeding ink in an ink tank to a pen tip and an ink collector in which a plurality of comb-tooth like elements formed with an air-liquid exchange groove are arranged at intervals in a feeder core axial direction. An ink holding plate is provided so as to face a rear end face of the ink collector in such a manner as to form a gap for holding the ink in the ink tank by way of the capillary phenomenon between the ink holding plate an the rear end face. A plurality of air exchange grooves in which ink flows and is discharged in an amount responding to a change in pressure in the ink tank into and from grooves between the comb-tooth like elements which are formed between an outer edge portion of the comb-tooth like element and a feeder core contact.

Writing implement

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 ( ), a plurality of cutouts ( ) are formed so that each cutout ( ) is formed to a right angle direction with respect to a center line ( ) of the sheet element ( ) with a length equal to or greater than half the radius (R) (A&gE;(R/2), B&gE;(R/2)) and that one end of the cutout ( ) is extended to the periphery.

Writing instrument

A writing implement having a cap member is provided and is a direct-flow type (liquid ink type) writing implement including: a barrel cylinder; a holder holding a pen core at a front end of the barrel cylinder and further having inside the barrel cylinder, an ink tank for storing a liquid ink and a collector for temporary retention thereof. The collector, barrel cylinder and ink tank are formed of a clear, transparent material. A mouthpiece at the outer periphery of the holder is formed of a resin material having the same color as the ink held in the ink tank or having the same color as the written ink. The barrel cylinder may have a partition wall, positioned near to the center, on the side (rear side) opposite to the position where the collector is arranged, forming an ink tank in a space inside the barrel between the rear end plate of the collector and the partition wall.

Liquid applicator having ink color identification

A free ink type writing instrument using an ink containing an organic solvent as a main solvent, wherein a temporary ink reservoir member has a larger critical surface tension than a surface tension of the ink, and an absolute value of a difference between values of solubility parameters of a material constituting the temporary ink reservoir member and a solvent contained in the ink is 1 or more.

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Gunma, Japan

Yoshiomi Konose