| 摘要 |
PROBLEM TO BE SOLVED: To prevent bending of bristles and opening of bristles when repeatedly using a toothbrush for a long time. ! SOLUTION: A toothbrush 1 has a handle body 10 and a head part 20 extended to the tip of the handle body 10. A plurality of bristle bundles 21 for a plurality of bristles 21a are implanted on the head part 20, and the whole or part of the bristles 21a comprises a filament made of polybutylene terephthalate. The filament has a zero shear viscosity of 200-300 Pa s at 240°C, and a breaking elongation per unit area of equal to or less than 2,600%. ! COPYRIGHT: (C)2015,JPO&INPIT |
