CA2238209A1

CA2238209A1 - Toothbrush

Info

Publication number: CA2238209A1
Application number: CA002238209A
Authority: CA
Inventors: Takayuki Watanabe
Original assignee: Johnson and Johnson KK
Current assignee: Johnson and Johnson KK
Priority date: 1997-05-23
Filing date: 1998-05-22
Publication date: 1998-11-23
Also published as: GB2325401A; BR9806565A; CN1178610C; JPH10323226A; JP4050356B2; CN1203767A; AU6805498A; US5991957A; GB2325401B; GB9811134D0

Abstract

In the case of conventional toothbrushes whose bristles have all needlelike tapering tips, the bristles near tips becomes too flexible because they are too thin. On the other hand, in the case of toothbrushes whose bristle ends being rounded or hemispherical, it is difficult to go into the spaces between teeth or boundary spaces between teeth and gums. Thus, it is difficult for conventional toothbrushes to clean up in every nook and corner in the mouth. A
toothbrush comprising a block head having brush portion, a handle and a neck portion connecting said block head with the handle, wherein a part of said tufts of the brush portion are made up of filament with polygonal cross section, and the rest of the tufts are made up of sheath-core structural filament whose core material is covered with sheath material so that the cross section thereof is concentric circles.

Claims

1. A toothbrush comprising a block head having a brush portion composed of tufts embedded on the block head, a handle and a neck portion connecting said block head with the handle, wherein a part of said tufts embedded to form the brush portion are made up of filament with polygonal cross section, and the rest of the tufts embedded are made up of sheath-core structural filament whose core material is covered with sheath material so that the cross section thereof is concentric circles.

2. The toothbrush according to claim 1 wherein said tufts of polygonal filament are embedded in tuft holes which mainly forms outer line of tuft holes on said block head, and tufts of the sheath-core structural filament are embedded in the rest of tuft holes.

3. The toothbrush according to claim 1 or 2 wherein said tufts of polygonal filament are embedded in tuft holes along periphery of said block head and tufts of the sheath-core structural filament are embedded in the rest of tuft holes so that the polygonal filament tufts surround the sheath-core structural filament tufts.

4. The toothbrush according to any one of claims 1 to 3 wherein said polygon of the polygonal filament is trigon, tetragon, pentagon, hexagon or octagon.

5. The toothbrush according to any one of claims 1 to 4 wherein said polygon of the polygonal filament is hexagon.

6. The toothbrush according to any one of claims 1 to 5 wherein said core part of the sheath-core structural filament is made of polyester resin and said sheath part thereof is polyamide resin.

7. The toothbrush according to any one of claims 1 to 6 wherein the tips of the sheath-core structural filaments have a circular cone shape and the points thereof are made of polyester resin, and the tips of said polygonal filaments have a round shape.

8. The toothbrush according to any one of claims 2, 4, 5, 6 and 7 where the tufts of sheath-core structural filaments, those of polygonal filaments and bristles thereof comprising:
a) said tufts forming three to six lines lined in width direction of the block head, b) the bristle lengths constructing both outermost lines are shorter than those of the other inner lines of tufts, c) the bristles of said inner lines being cut so as to form continuous six or more cut surfaces lined in longitudinal direction of the toothbrush.

9. The toothbrush according to claim 1 where the tufts of sheath-core structural filaments, those are of polygonal filaments and bristles thereof comprising:
a) said tufts forming three to five lines lined in width direction of the block head, b) the bristle lengths constructing both outermost lines are shorter than those of the other inner one to three lines of tufts, c) the bristles of said inner lines being cut so as to form continuous six cut surfaces lined in longitudinal direction, d) in the cut surfaces, the bristles of the first cut surface nearest to the brush end being cut so that the brush end bristles are shortest and the bristles lengthen toward the handle at an angle from the block head surface of 20° to 30°
at the brush end to be replaced by the second cut surface which forms the first top horizontal cut surface at the third bristle row from the brush end without difference in level, e) the bristles of the third cut surface continuing from the second cut surface become short from the handle side of the second cut surface at an angle 20° to 30° to the block head surface to form the bottom at fourth or fifth row from the brush end, f) the fourth, fifth and sixth cut surfaces are symmetrical to the first, second and third cut surfaces about the perpendicular plane including the block head and said bottom line, g) the ratio of the height of the top horizontal cut wherein said core part surface: E to the height of the bottom: F is; E/F=1.05 to 1.2, h) the ratio of the height of the top horizontal cut surface: E to the height of lowest part of the first cut surface: G is; E/G=1.1 to 1.3 and, i) the surface formed by the tips of the bristles embedded outer rows is parallel to the block head surface and the bristle length thereof is about the same as that of the bottom.

10. The toothbrush according to any one of claims 1 to 9 where the bristle lengths of the first and the second top horizontal cut surfaces are substantially the same.