Patent ID: 7252449

Claim:
A retractable writing tool comprising: a rear barrel ( 202 ) and a front barrel ( 207 ) having an opening ( 203 ) and a tip ( 101 ) capable of moving between a retracted position and a protracted position; a feeder ( 107 ) capable of conveying fluid to the tip ( 101 ) and a valve ( 206 ) having a front end ( 103 ) and a back end ( 104 ), where the front end ( 103 ) has a round face with a concave shape profile at the point where the tip is to exit and a slit ( 600 ), the front end ( 103 ) is adjacent to the opening ( 203 ) of the front barrel ( 207 ) so that in the retracted position the tip ( 101 ) is between the front end ( 103 ) and the back end ( 104 ) substantially sealed from outside air to substantially prevent the writing fluid from evaporating to the outside air, and preventing the release of vapor fluid from within the enclosure ( 102 ) when the tip ( 101 ) is in a retracted position, where in the protracted position, the tip ( 101 ) extends through the slit ( 600 ) of the valve ( 206 ) and opening ( 203 ) of the front barrel ( 207 ), where the valve ( 206 ) is made of silicone.