| 摘要 |
<p>Novel, improved filaments (20) for brushes. The filaments (20) include a colored region (26) provided by a dye colorant and the colored region (26) is adapted to provide a color intensity which can change in response to increased use of the filament to provide a signal indicative of filament wear. The filaments (20) are particularly useful in toothbrushes.</p> |
