| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a water-base ballpoint pen, which realizes a stable ink efflux to the last by proper flow rate in comparatively finer drawing line with clearly developed color and excellent erasability by an eraser with no clogging of the ink in a ball house. <P>SOLUTION: In the water-base ball-point pen having an ink housing tube with a water-base ink including the water, 3-30 wt.% of non-thermoplastic colored resin particles having the average particle diameter of 1-15 μm and 0.1-10 wt.% of non-colored particles, a holder at a tip has the ball house and an ink guiding hole, which passes through from the opposite side of the ball house to the ball house in order to feed the ink to a ball under the condition that the distance between the edge face of the ball and the side surface of the ball house is set to be 5-25 μm under the state that the ball is placed at the center of the ball house, the ratio of the area of a flow passage to the cross-sectional area of the ball is set to be at least 0.52, the ratio of the area of an ink groove to the area of the ink guiding hole is set to be at least 1.00 and the diameter of the ball is set to be 0.44-0.56 mm. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
