Patent ID: 6044514
Filing Date: 2000-04-04
Classification: A46B,A46D,Y10S

Abstract:
A toothbrush comprising:a plurality of tufts each of which comprises a plurality of bristles embedded respectively in bored holes which are vertically and laterally formed in a head portion of the toothbrush;wherein:each of said tufts comprises first and second bristles, and in each of said tufts, a total of the first and second bristles is at least 50% of the bristles in each tuft;said first bristles are tapered bristles having a factorial coefficient n=0.29 to 0.51 in the following equation (I);distal ends of said second bristles are located in a lower position than distal ends of said first bristles; andvertical intervals between each of said bored holes are from 1.2 mm to 3.0 mm, and lateral intervals between each of said bored holes are from 0.75 mm to 1.5 mm;r(x)=a{(L-x)/L}.sup.n (I)wherer(x): sectional radiusx: length from base of each bristleL: length to distal end from base of each bristlea: sectional radius in case x=0[=r(0)]n: factorial coefficient.