TOOTHBRUSH

Abstract: A toothbrush which has a head and a grip handle, with bristles extending from a bristle face of the head, in which at least some of the bristles are arranged in tufts which have a sectional shape, or are arranged in clusters of tufts which have a sectional shape, which tapers in a direction either away from, or in alternative embodiment towards, the outer edges of the bristle face toward the longitudinal axis, i.e. being respectively wider or narrower at the end towards the said outer edge.

Description: Toothbrush This invention relates to toothbrushes, particularly to hand held toothbrushes having a novel bristle configuration. Toothbrushes generally comprise a head and a grip handle disposed along a longitudinal axis. Bristles extend from a bristle face of the head in a general bristle direction. Generally the bristles are arranged in tufts which are circular in section across the general bristle direction at their base on the bristle face, although some toothbrushes are known having tufts of other sectional shapes, for example as disclosed in WO95/06420. US 4617695 discloses a toothbrush with all its tufts of a hexagonal section. GB 705725 discloses a toothbrush with tufts of rectangular section. WO 91/19437 discloses a toothbrush having all its tufts of an elongated oval shape with the long axis of the oval across the longitudinal axis of the head. Circular section tufts are sometimes not able to reach into the interdental spaces, or otherwise adapt themselves to the shape of the teeth and adjacent areas of the gums, resulting in a reduced cleaning efficiency. It is an object of this invention to provide a toothbrush having a novel bristle configuration which in pan at least solves this problem. According to one form of this invention, a toothbrush has a head and a grip handle disposed along a longitudinal axis, with bristles extending from a bristle face of the head in a general bristle direction generally perpendicular to the longitudinal axis, characterised in that at least some of the bristles are arranged in tufts which have a sectional shape, or are arranged in clusters of tufts which have a sectional shape, across the general bristle direction, which tapers in a direction away from. the outer edges of the bristle face toward the longitudinal axis, being wider at the end towards the said outer edge. In a second form of this invention, a toothbrush has a head and a grip handle disposed along a longitudinal axis, with bristles extending from a bristle face of the head in a general bristle direction generally perpendicular to the longitudinal axis, characterised in that at least some of the bristles are arranged in tufts which have a sectional shape, or are arranged in clusters of tufts which clusters have a sectional shape, across the general bristle direction, which tapers in a direction away from the longitudinal axis towards the outer edges of the bristle face, being narrower at the end towards the said outer edge, said tapering section tufts being combined with tufts of other sectional shapes in the raft pattern. The toothbrush of this invention may be provided with a combination of tufts or clusters of both of the above -described sectional shapes, i.e. one or more tufts or clusters which taper in a direction away from the longitudinal axis, and one or more tufts or clusters which taper in a direction toward the longitudinal axis. Examples of sectional shapes which taper in the above-described ways are triangles, with an apex towards the longitudinal axis and a base facing, suitably substantially parallel to, the outer edge, or with an apex toward the outer edge and a base facing, suitably substantially parallel to, the longitudinal axis. Such triangles may be equiangular, i.e with all three angles and sides the same, or may be irregular, i.e with all three angles and sides different. Such triangles may be isosceles triangles, i.e with two sides and their respective angles with the base being the same, for example with their base generally aligned with the longitudinal axis of the toothbrush. Such triangles may be right-angled triangles, for example with a first side substantially parallel to the longitudinal axis and a second side perpendicular to the first side. Suitably the tufts themselves are of the said tapering sectional shape. The above described triangular sectioned tufts may themselves be arranged in clusters of various numbers of tufts in various shapes, particularly in triangular clusters. For example two such right-angled triangle sectioned tufts may be arranged back-to-back to produce an isosceles triangle shaped cluster. For example three such triangular sectioned tufts may be arranged with their apexes pointing inwardly to form a triangular cluster. The above mentioned tapering sectional-shaped clusters may alternatively be made up of tufts which have a conventional rounded shape, e.g made up into a triangle shaped cluster. For example three or more circular section tufts may be arranged in a triangle shaped cluster. Other examples of such sectional shapes which taper in the above-described ways are pear shapes and ogival shapes, and semi circles or semi ellipses. Also the tufts may have shapes which are bisected by the longitudinal axis, each half of the bisected shape forming one of the above-described shapes. Examples of such shapes include diamond shapes and butterfly shapes. For example bisection of a diamond shape by an axis passing through two opposed apexes generates two triangle shapes on either side of the axis, and bisection of a diamond shape by an axis passing through its waist generates two triangle shapes on either side of the axis. Suitably tufts and clusters of tufts having sectional shapes which taper have a point or a base, as appropriate, which lies at or along the outer edge of the tuft pattern on the bristle face, to enable the said tufts to easily come into contact with the teeth during brushing. The above mentioned tufts and clusters having a sectional shape which tapers (respectively "first tufts and clusters") may be combined in a tuft pattern with tufts of other sectional shapes to enhance the cleaning effect. The said first tufts and clusters tufts have the advantage of improved conformation to the concavity of the curve of the gumline where the teeth meet the gums, and the combination of these tufts with tufts of other sectional shapes can enhance the cleaning effect, for example if such other sectional shaped mfts are suited to clean other areas of the tooth or gum surface, the gumline or interdental spaces. Such mfts of other sectional shapes may be of a conventional circular section shape, but in one such embodiment of this invention first mfts are combined with mfts (termed herein "second mfts"), having a sectional shape across the general bristle direction, which is elongated in a direction generally aligned with the longimdinal axis. Examples of such shapes are rectangular or lozenge shapes elongated in a direction generally parallel to the longimdinal axis. At the end of the head extreme from the handle, there may be a rounded, e.g. circular, oval or polygonal pattern of mfts for example in the form of a polygon of mfts optionally surrounding a central tuft, or alternatively a single large section tuft of rounded or polygonal shape (all herein termed "third tuft(s)"),. The term "rounded" used in the context of these third tuft(s) means an imaginary closed curved line can be drawn through the mfts at the perimeter of the cluster, e.g through the corners of a polygon. In another embodiment the said first mfts may be combined with one or more mfts (termed "fourth mfts") which have a sectional shape across the general bristle direction which is longer in a direction generally perpendicular to the longimdinal axis than along this axis. For example the shape may be an oval, rectangular or lozenge shape elongated in a direction generally perpendicular to the longimdinal axis. Also, when two of the said first mfts or clusters are arranged opposite each other on opposite sides of the longimdinal axis, between them, i.e. on or disposed about the longimdinal axis there may be one or more mfts simated between them. In one embodiment of this invention the said first, second, third and fourth mfts may be arranged on the toothbrush head in an arrangement comprising a pattern of third mfts at the end of the head remote from the handle, then a sequence of sets of first mfts evenly disposed on either side of the longimdinal axis optionally with one or more fourth mfts between them, longitudinally alternating with a pattern of second mfts. Suitably in this embodiment there are first mfts longitudinally adjacent to the third mfts, adjacent the base end of the head, and at or near the longimdinal midpoint of the head. In another embodiment of this invention the said first, second and third mfts may be arranged on the toothbrush head in an arrangement comprising a pattern of third mfts at the end of the head remote from the handle, then in sequence towards the handle a sequence of one or more transverse rows of second mfts, then sets of first mfts of triangular section evenly disposed on either side of the longimdinal axis, optionally with one or more fourth mfts between them, then a further sequence of one or more rows of second mfts, then adjacent the base of the head a further set of first mfts of triangular section evenly disposed on either side of the longimdinal axis. In the above described embodiments the said first, second, third and fourth mfts may all extend to the same distance from the bristle face, or they may vary in length so that the ends of the bristles remote from the bristle face lie in an undulating surface. Suitably the said first, and optionally also the said third, mfts may be longer than the said second mfts. The mfts of bristles, of all types, may be fixed into the toothbrush head by conventional means, for example conventional small metal clips retaining them in socket holes in the head, or alternatively they may be fused into the material of the head by known processes, e.g. as disclosed in US 4637660 or EP 0142885A. The head and handle of the toothbrush may be made of plastics materials which are conventional in the toothbrush industry, using a conventional injection moulding process. Alternatively the head and handle may be made by the novel process disclosed in GB 9513883.0 (filed 7 July 1995 and continued as a PCT application claiming priority therefrom, the contents of which are included herein by way of reference), in which the head is made first with a first engagement part and the handle is then formed with a second engagement part in engagement with the first engagement part. The head and handle may include known feamres of toothbrushes, for example elastomeric grip mats on the handle, and regions which modify flexibility, for example folded regions or cut-outs containing an elastomeric material. The head may have an undulating surface as disclosed in PCT/EP96/00714, the contents of which are included herein by way of reference. The bristles may be made of conventional materials, for example known nylon filaments. The invention will now be illustrated by way of example only, with reference to the accompanying drawings. Fig 1 shows a plan view of a toothbrush head of this invention. Fig 2 shows a perspective view of the toothbrush head of Fig 1. Fig 3 shows a plan view of an alternative toothbrush head of this invention. Fig 4 shows a plan view of another alternative toothbrush head of this invention. Referring to Figs 1 and 2, the head 1 of a toothbrush is shown in a plan view. At one end the head 1 connects to a grip handle (not shown) via neck 2 in a conventional manner, the head 1 and handle being integrally made of plastics material. The head 1 and handle lie along a longimdinal axis A— A. From a bristle face 3 of the head 1 extend bristles 4, 5, 6, 7 arranged in mfts. The view of Fig 1 (and Fig. 3) is down the general bristle direction B— B in which the bristles extend. Some of the mfts 4 are arranged in mfts which have a section, across the general bristle direction, which is a right-angled triangle, with one of the right angled sides generally peφendicular to the longimdinal axis A—A, and the other generally parallel to it. The cross section of these triangles taper in a direction away from the outer edge of the bristle face 3 , with their base toward the outer edge. At about the longimdinal mid-point along the edge, two such mfts on each side of the longimdinal axis A--A, 4A, 4B are arranged back-to-back to form an isosceles triangle. The triangular section mfts 4 are disposed such that one of then- edges lies at the outer edge of the tuft pattern, with an apex toward the longimdinal axis A— A. Alternating with the triangular section mfts 4 is a pattern of second mfts 5, which have a sectional shape, across their bristle direction, which is elongated in a direction generally parallel to the longimdinal axis A--A, being substantially lozenge shaped. At the end of the head 1 remote from the neck 2 are third mfts 6 in the form of a polygonal pattern arranged around a central tuft. Where some of the first mfts 4 are opposite each other across the longimdinal axis A— A there are fourth mfts 7 between them, on the longimdinal axis A-A of the head 1 , having a sectional shape across their bristle direction which is elongated in a direction across the longimdinal axis A— A, being of oval section. As shown in Fig. 2 the first, third and fourth mfts 4, 6, 7 extend further from the bristle face 3 than the second mfts 5, so that the surface in which the ends of the bristles remote from the bristle face 3 is undulating. Referring to Fig. 3 an alternative construction of toothbrush head is shown, in which feamres corresponding to the toothbrush of Figs 1 and 2 are correspondingly numbered. In the toothbrush of Fig 3 the first mfts 8, 8 A, 8B are right angled triangle shaped in section across the bristle direction, but taper in a direction away from the longimdinal axis A-A, such that the base of the triangle faces the longimdinal axis and the apex is toward the outer edge of the tuft pattern. Referring to Fig. 4 another alternative construction of toothbrush head is shown. First 4, second 5 and third 6 mfts are arranged on the toothbrush head 1 in an arrangement comprising a pattern of third mfts 6, in the form of a polygonal pattern arranged around a central tuft, at the end of the head 1 remote from the neck 2. In sequence towards the neck 2 is firstly a sequence of three rows of second mfts 5A. This is followed by a set of first mfts 4A of triangular section, in two clusters each of three triangular sectioned mfts 4A, the section of each of which tapers in a direction away from the outer edge of the bristle face 3, being in a triangular pattern, itself with its base towards the edge of the bristle face 3 , being evenly disposed on either side of the longimdinal axis A-A. Then there is a further sequence of rows of second mfts 5B. Then adjacent the base of the head 1 is a further set of first mfts 4 of triangular section, in two clusters each of three triangular sectioned mfts 4, the section of each of which tapers in a directior. away from the outer edge of the bristle face 3. being in a triangular pattern, itself with its base towards the edge of the bristle face 3. being evenly disposed on either side of the longimdinal axis A-A. The toothbrush of Figs. 1, 2, 3 and 4 is used in the same way as known toothbrushes, preferably in a manner as recommended by dental practitioners. The triangular sectional shape of the first mfts 4 and 8 enable the bristles in these tufts to accommodate themselves better to the shape of the teeth, particularly the gumline. The second, third and fourth mfts 5, 6 and 7 facilitate cleaning of the other areas of the teeth and the interdental spaces. The overall combination of mfts on the toothbrush of the invention therefore results in an advantageous tooth cleaning effect.

Claims: Claims: 1. A toothbrush which has a head (1) and a grip handle (2) disposed along a longimdinal axis, with bristles (4, 5, 6, 7) extending from a bristle face (3) of the head (1) in a general bristle direction generally perpendicular to the longimdinal axis, characterised in that at least some of the bristles are arranged in mfts (4) which have a sectional shape, or are arranged in clusters of mfts which have a sectional shape, across the general bristle direction, which tapers in a direction away from the outer edges of the bristle face (3) toward the longimdinal axis, being wider at the end towards the said outer edge. 2. A toothbrush which has a head (1) and a grip handle (2) disposed along a longimdinal axis, with bristles extending from a bristle face (3) of the head (1) in a general bristle direction generally perpendicular to the longimdinal axis, characterised in that at least some of the bristles are arranged in mfts (8) which have a sectional shape, or are arranged in clusters of mfts which clusters have a sectional shape, across the general bristle direction, which tapers in a direction away from the longimdinal axis towards the outer edges of the bristle face (3), being narrower at the end towards the said outer edge, said tapering section mfts being combined with mfts (5, 6, 7) of other sectional shapes in the mft pattern. 3. A toothbrush according to claim 1 or claim 2 characterised in that it is provided with a combination of one or more mfts (8) or clusters which taper in a direction away from the longimdinal axis, and one or more mfts (4) or clusters which taper in a direction toward the longimdinal axis. 4. A toothbrush according to any one of claims 1 to 3 characterised in that the said sectional shapes which taper are triangles. 5. A toothbrush according to any one of claims 1 to 4 characterised in that the mfts themselves are of the said tapering sectional shape. 6. A toothbrush according to claim 5 characterised in that triangular sectioned mfts are themselves arranged in triangular clusters (4B, 8 A, 8B). 7. A toothbrush according to claim 6 characterised in that two right-angled triangle sectioned mfts (8A, 8B) are arranged back-to-back to produce an isosceles triangle shaped cluster. 8. A toothbrush according to claim 6 characterised in that three triangular sectioned mfts are arranged with their apexes pointing inwardly to form a triangular cluster (4B). 9. A toothbrush according to any one of claims 1 to 4 characterised in that tapering sectional-shaped clusters are made up of mfts which have a rounded shape and are arranged in a triangle shaped cluster. 10. A toothbrush according to any one of the preceding claims characterised in that mfts and clusters of mfts having sectional shapes which taper have a point or a base, as appropriate, which lies at or along the outer edge of the mft pattern on the bristle face. 11. A toothbrush according to any one of the preceding claims characterised in that the mfts (4) and/or clusters having a sectional shape which tapers (respectively "first mfts and clusters") are combined in a mft pattern with mfts (5) ("second tuft(s)") having a sectional shape across the general bristle direction, which is elongated in a direction generally aligned with the longimdinal axis. 12. A toothbrush according to any one of the preceding claims characterised in that at the end of the head (1) extreme from the handle (2), there is a rounded, or polygonal pattern of mfts (6) or alternatively a single large section mft of rounded or polygonal shape ("third mfts"). 13. A toothbrush according to any one of the preceding claims characterised in that the said first mfts (4) are combined with one or more mfts (7) which have a sectional shape across the general bristle direction which is longer in a direction generally perpendicular to the longimdinal axis than along this axis ("fourth mfts"). 14. A toothbrush according to any one of the preceding claims characterised in that two of the said first mfts or clusters (8A, 8B,) are arranged opposite each other on opposite sides of the longimdinal axis and there are one or more mfts (7) simated between them. 15. A toothbrush according to any one of the preceding claims characterised in that the said first, second, third and fourth mfts (4, 5, 6, 7) vary in length so that the ends of the bristles remote from the bristle face lie in an undulating surface. 16. A toothbrush according to claim 15 characterised in that the said first (4), and optionally also the said third (6), mfts are longer than the said second mfts (5).

Inventors: GONSER FRANK, JANITZ PETER, KRAEMER HANS, TOPFER KIRSTEN, GONSER, FRANK, JANITZ, PETER, KRAEMER, HANS, TOPFER, KIRSTEN
Applicants: GONSER FRANK, JANITZ PETER, KRAEMER HANS, SMITHKLINE BEECHHAM CONSUMER H, TOPFER KIRSTEN, GONSER, FRANK, JANITZ, PETER, KRAEMER, HANS, SMITHKLINE BEECHHAM CONSUMER HEALTHCARE GMBH, TOPFER, KIRSTEN
Application year: 1996
Main classification: A46B9
IPC codes: A46B9