| 摘要 |
<p>A toothbrush having a bristle face has a surface that is displaced in the general bristle direction to a varying extent with distance along the length of the head, with at least two high parts with at least one low part longitudinally in between, and the length of the bristles also varying at different positions on the bristle face such that longer bristles extend from low parts of the bristle face and shorter bristles extend from high parts of the bristle face, so that the stiffness of the bristles, varies with distance along the length of the head.</p> |
