| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a toothbrush capable compatibly attaining gentle contacting feeling to gums and high cleaning property to cervical regions of the tooth. <P>SOLUTION: The bristle implanting surface 5 has the central bristle bundle group 14 comprising a plurality of the central bristle bundles 12 and generally centrally located, the first outside bristle bundle group 24a implanted sandwiching the central bristle bundle group 14 and comprising a plurality of outside bristle bundles 22, and the second outside bristle bundle group 24b, the zone of the central bristle bundle group 14 is the central implanting area 11, the central implanting density is the value obtained by dividing the total number of the bristles constituting the central bristle bundle group 14 by the area of the central implanting area 11, the zone of the first outside bristle bundle group 24a is the first outside implanting zone 21a, the zone of the second outside bristle bundle group 24b is the second outside implanting zone 21b, the outside implanting density is the value obtained by dividing the total number of the outside bristle 23 by the sum of the area of the first outside implanting zone 21a and the area of the second outside implanting zone 21b, and the implanting density ratio represented by the outside implanting density/the central implanting density is 1.6 to 6.0. <P>COPYRIGHT: (C)2012,JPO&INPIT |
