| 摘要 |
PROBLEM TO BE SOLVED: To make a tip part hard to get worn during writing even when it is in abutment with the surface of a piece of paper by incorporating an additive in a synthetic resin composition forming the leading tip part of a writing tool for increasing the wear resistance. SOLUTION: A tip 6 of synthetic resin to be press fitted and secured at a front portion of a slider 5 in such a manner as to envelop a core holding portion 5a of a tip of the slider 5 is formed from POM (acetal) resin, ABS resin or polypropylene as a raw material and molybdenum, tungsten, silicone, graphite or carbon added in advance for increasing the wear resistance. When writing is continued while the slider 5 is being retracted that holds a core at a strength bearing the writing pressure generated during writing, the distal end of the tip 6 is put in a state in which it is brought into abutment with the surface of a piece of paper and the tip is subjected to easy wear. However, it is possible to make the tip difficult to wear by adding an additive in the synthetic resin composition forming the leading tip 6 of the slider 5 for increasing the wear resistance. |
