WO2010069917A1

WO2010069917A1 - Toothbrush

Info

Publication number: WO2010069917A1
Application number: PCT/EP2009/067073
Authority: WO
Inventors: Wolf-Dieter Mueller
Original assignee: Glaxosmithkline Consumer Healthcare Gmbh & Co. Kg
Priority date: 2008-12-15
Filing date: 2009-12-14
Publication date: 2010-06-24
Also published as: AU2009327193A1; CN102245051B; GB0822855D0; CN102245051A; AU2009327193B2; JP5759380B2; MY159466A; MX2011006336A; NZ592895A; ZA201103891B; AR074601A1; KR20110097958A; US20100223746A1; TW201032752A; EP2385772B1; CA2745966A1; JP2012511943A; CO6382095A2; EP2385772A1

Abstract

A toothbrush head with plural tufts of bristles comprising tapered bristles and plural non-tapered bristles. Tufts containing tapered bristles are arranged along the widthways opposite outermost sides of the tuft pattern and are of a greater length than inner tufts which contain non tapering bristles.

Description

TOOTHBRUSH

This invention relates to toothbrushes, in particular to the bristle configuration of toothbrushes. Especially this invention relates to improved toothbrush bristle configurations comprising tapered bristle filaments. Toothbrushes are well known articles generally comprising a head for insertion in the user's mouth and a grip handle to be held during use, with a neck region in between, all arranged along a toothbrush longitudinal direction (not necessarily a straight line). The toothbrush head normally has a surface, termed herein the "bristle surface" from which bristles extend from a lower end of the bristles closest to the bristle surface to an upper end distant from the bristle surface. The bristle surface is bounded at its widthways opposite edges by side surfaces.

Toothbrush bristles are also well known articles, generally comprising a filament of a stiff but flexible material, disposed in tufts of plural filaments extending from the bristle surface. The polyamide Nylon is very frequently used as a toothbrush bristle material.

Toothbrush bristle filaments may be of two known types. Non-tapered bristles have substantially the same cross-section, typically cylindrical, along their entire length from their lower to their upper end except for the extreme upper end, e.g. the uppermost 5% or less, which is end-rounded, e.g. in an irregular hemisphere or hemi- ellipsoidal shape. So called "tapered bristles" are known, which taper for a substantial part of their length, e.g. 20% or more of their length, toward their end remote from the bristle face, typically in a shallow pointed conical shape. Tapered bristles, being thinner at their upper end, have different bending and flexibility characteristics to non-tapered filaments. In particular tapered bristles are known for efficacy in reaching into the spaces between the teeth, the so called "interproximal" spaces. For example such tapered bristles are disclosed in EP-A-I 234 525, EP-A-I 415 572, US-A- 6,546,586, WO-A-97/42853, WO-A-97/42854, WO-A-01/32053, WO-A-01/82741, EP-A-O 596 633 among others.

Particular relative dispositions of the tapered bristles on the bristle surface are also known. For example US-A-6,546,586 discloses a toothbrush head in which each tuft comprises plural bristles made of polybutylene terephthalate in the form of shorter bristles of uniform cross section and longer tapered bristles which taper toward their upper end. It is known to combine tapering and non-tapering bristles on a toothbrush head, e.g. from US-A-2006/0096053 which discloses a head for an electric toothbrush. It is also known from other disclosures to combine long and short bristle filaments in a tuft e.g. US-A-3, 103,679, WO-A-96/16571 and DE-A-35 28 596. WO- A-2009/000903 discloses a toothbrush head having an inner region of tapered bristles surrounded by an outer ring of non-tapered bristles. Other types of toothbrush bristles are known which narrow at their ends remote from the bristle surface. For example there are so called "feathered bristles" in which the ends remote from the bristle surface are split into even finer filaments. For example feathered bristles are disclosed in EP-A-I 173 081 and US-A-6,322,152.

It is an object of this invention to explore the possibilities of toothbrush heads with combinations of tapered and non-tapering bristles, especially with the intention of providing an improved toothbrush head incorporating tapered bristle filaments, e.g. providing tooth cleaning, particularly in the interproximal spaces, at the gingival margin, and in subgingival access. Other objects and advantages of the invention will be apparent from the following description. According to a first aspect of this invention a toothbrush head is provided, being connected to or connectable to a toothbrush grip handle to thereby define a head - grip handle longitudinal direction, the head being elongate in the longitudinal direction and having a width direction perpendicular to the longitudinal direction, the head having a bristle surface from which plural tufts of bristles extend in a bristle direction, the bristles being arranged in plural tufts each of which contains plural bristles, the bristles comprising plural tapered bristles and plural non-tapered bristles; characterised in that the plural bristle tufts are arranged in a pattern on the bristle surface comprising plural outer tufts containing tapered bristles and arranged along the widthways opposite outermost sides of the tuft pattern and being of a first greater length, and widthways between the plural outer tufts being plural inner tufts containing non tapering bristles and being of a second lesser length shorter than the first greater length.

It is believed that this novel arrangement of tapered bristles facilitate effective cleaning at the gum margin. Other advantages of the toothbrush head of the invention will be apparent from the following.

The toothbrush head of this invention may be realized in various constructions.

For example all of the plural outer tufts may contain tapered bristles. For example all tufts which contain tapered bristles may be entirely composed of tapered bristles.

Alternatively the plural outer tufts may comprise tufts which contain tapered bristles and tufts which do not contain tapered bristles, and which may be of the first greater length or a greater or lesser length than this first greater length. For example the plural outer tufts may comprise tufts or groups of tufts which contain tapered bristles alternating longitudinally with tufts or groups of tufts which do not contain tapered bristles.

For example all of the plural outer tufts may be of the first greater length. For example all of the plural outer tufts may be of the same first greater length.

Alternatively the plural outer tufts may comprise tufts of two or more first greater lengths longer than the second lesser length. For example alternatively the plural outer tufts may also comprise tufts of a length which is the same as or less than the second lesser length. For example all of the inner tufts may contain non-tapered bristles.

For example all of the inner tufts may be composed entirely of non-tapered bristles. Alternatively some of the inner tufts may include tapered bristles.

For example all of the inner tufts may be of the second lesser length, for example all of the inner tufts may be of the same second lesser length. Alternatively the plural inner tufts may comprise tufts of two or more second lesser lengths shorter than the first greater length. For example alternatively the plural inner tufts may also comprise tufts of a length which is the same as or greater than the first greater length.

The plural outer tufts may be arranged in lines which substantially follow the shape of the edge of the bristle surface as viewed along the length of the bristles down toward the bristle surface.

For example in this arrangement the outer tufts may be arranged with each outer tuft substantially equidistant in the widthways direction from the widthways edge of the bristle surface.

For example the plural outer tufts may be arranged such that each tuft is substantially widthways equidistant from the adjacent edge of the bristle surface. Alternatively the plural outer tufts may be arranged such that different tufts are at different widthways distances from the adjacent edge of the bristle surface. For example plural outer tufts may be arranged widthways adjacent each other at two or more respective widthways distances from the edge of the bristle surface. Tufts containing tapered bristles, for example of the first greater length, may also be also located adjacent to the end of the bristle surface longitudinally remote from the grip handle. For example such tufts may be the tufts most longitudinally remote from the toothbrush grip handle. Such tufts may be composed entirely of tapered bristles or may comprise tapered bristles in combination with non-tapered bristles. For example such tufts may comprise tufts which contain both tapered and non-tapered bristles, or may comprise adjacent tufts composed respectively entirely of tapered bristles and non-tapered bristles. Additionally or alternatively, tufts, for example of the first greater length, may also be also located adjacent to the end of the bristle surface adjacent to the position of the toothbrush head at which the head is connected or is to be connected to the grip handle. For example such tufts may be the tufts most longitudinally closest to the toothbrush grip handle. Such tufts may be composed entirely of tapered bristles or may comprise tapered bristles in combination with non-tapered bristles. For example such tufts may comprise tufts which contain both tapered and non-tapered bristles, or may comprise adjacent tufts composed respectively entirely of tapered bristles and non-tapered bristles.

For example the difference between the first greater length and the second lesser length may be 1 - 5 mm, for example 2 - 4 mm. Typically the first greater length may be 11 - 13 mm.

The tufts containing tapered bristles and tufts containing non-tapered bristles may be positioned in otherwise conventional layouts on the bristle face. For example tufts may be arranged in a two-dimensional array with immediately adjacent tufts ca. 2 - 3 mm apart, for example in a regular layout symmetrical about the longitudinal direction. Such a layout may comprise rows of plural bristle tufts oriented widthways across the bristle surface.

The bristle surface may be substantially planar. Alternatively the bristle surface may be concave in the longitudinal direction and/or the widthways direction. For example the bristle surface may be concave curved or the surface may comprise planar regions at an obtuse angle to each other. For example the bristle surface may comprise a tip region adjacent to the tip end of the head remotest from the handle, which is at an obtuse angle to a region immediately longitudinally thereto. For example the tip region may be angled up relative to the region immediately longitudinally thereto.

The tufts containing tapered bristles and/or tufts containing non-tapered bristles may be oriented perpendicular to the bristle surface. Alternately they may be oriented to lean at a non-perpendicular angle to the bristle surface, such as at 75-85° to the bristle surface. Such leaning tufts preferably lean in the longitudinal direction so that their end remote from the bristle surface is either longitudinally closer or further from the grip handle. In one form of such a construction, widthways adjacent tufts may lean in opposite longitudinal directions. For example as seen looking in the widthways direction such tufts may appear to cross in an X arrangement. The tufts of tapered and non tapered bristles may be fastened into the bristle surface by conventional methods. Such conventional methods include the well known use of small metal "anchors" i.e. clips around the parts of the bristles which are to be fixed into the bristle surface, which are then wedged into socket holes in the bristle surface. Another conventional method is the so-called "anchorless" method in which the ends of the bristles to be fixed into the bristle surface by moulding the plastics material of the head around them in the mould cavity in which the head is made. In a first construction the toothbrush head may comprise a conventional unitary block of a plastic material such as conventional polypropylene into which the tufts are fastened. Alternatively in a second construction the toothbrush head may have a construction in which a section of the head which is relatively closer to the end of the head remote from the grip handle is resiliency and flexibly linked to a section of the toothbrush head which is relatively closer to the grip handle. Such a link may be by means of a composite link region composed of one or more flexible plastics material link and an elastomer material such as a thermoplastic elastomer. Such a head construction is for example disclosed in WO-A-97/07707 and WO-A-98/37788.

In such a second construction for example one of such sections, i.e. either that closer to the end of the head remote from the grip handle, or the section of the toothbrush head which is closer to the grip handle, or both such sections may have bristle tufts extending therefrom which are arranged in the pattern on the bristle surface comprising plural outer tufts containing tapered bristles and arranged along the widthways opposite outermost sides of the tuft pattern and being of a first greater length, and widthways between the plural outer tufts being plural inner tufts containing non tapering bristles and being of a second lesser length. Alternatively in a third construction the toothbrush head may have a construction in the form of three or more, but preferably three, longitudinally elongate sections disposed widthways adjacent across the toothbrush head, each section being flexibly linked to the handle, and being in the form of two widthways oppositely disposed outer sections with at least one, but preferably one, middle section disposed widthways between said outer sections, each section independently resiliency moveable relative to a widthways adjacent section, the plural outer tufts containing tapered bristles of the first greater length being disposed on the two widthways oppositely disposed outer sections, and the plural inner tufts containing non tapering bristles and being of a second lesser length being disposed on the at least one inner section. Each such section has its own respective bristle surface which together form the bristle surface of the toothbrush head.

An example of this latter construction is as disclosed in WO-A-2004/041023.

For example such a head construction may comprise three widthways adjacent, longitudinally extending sections from which bristles extend, being a middle section and an outer section on each widthways side of the middle section, one or more section being resiliency flexibly connected or connectable to the grip handle, and in which the end of the middle section adjacent to the tip end of the head is integrally widthways enlarged relative to the part of the middle section immediately longitudinally adjacent nearer to the handle to provide a bristle-carrying pad adjacent to the tip end of the head and which extends across the entire width of the toothbrush head adjacent to the tip end, the middle section comprises an intermediate bristle-carrying pad, being a region of maximum width of the part of the middle section between the tip pad and the base end of the head, with a first link region of the section between the tip pad and the intermediate pad being narrower in width than the adjacent part of the tip pad and the intermediate pad, and a second link region of the section between the intermediate pad and the handle being narrower in width than the adjacent part of the intermediate pad closer to the tip end.

Preferably the head comprises only three such sections, i.e. a middle section and two outer sections. For example the middle section may widen widthways at a region 50% or less, e.g. 25% or less of the longitudinal length of the middle section distanced from the tip end, relative to a region immediately longitudinally adjacent thereto closer to the grip handle. The end of the middle section adjacent to the tip end of the head may be integrally widthways enlarged relative to the part of the middle section immediately longitudinally adjacent nearer to the handle so as to form a concavity between the end of the middle section and the part of the middle section immediately longitudinally adjacent nearer to the handle, and the end of an outer section may be shaped in a complementary shape to the concavity so that this end may fit into the concavity.

Preferably two or more, preferably all of the sections are resiliently flexibly connected to the grip handle so that the section may be resiliently bent out of a plane parallel to the longitudinal and width directions under the action of pressure on the bristles. Preferably each section is resiliently linked to the grip handle by means of a flexible neck region of the grip handle.

For example the middle section and side sections may be in sliding contact. WO-A-2005/039858 describes a process by which such a head might be made.

In this third construction, for example, all of the plural outer tufts on the two outer sections may be tapered bristles of the first greater length, and all of the plural inner tufts on the middle section(s) may be non tapering bristles of the second lesser length.

In this third construction plural tufts comprising tapered bristles may extend from the middle section adjacent to the tip end of the middle section such that such tufts are the tufts most longitudinally remote from the toothbrush grip handle. The invention also provides a toothbrush comprising a grip handle connected to a toothbrush head as disclosed herein. Such a toothbrush may be a manual toothbrush intended to be moved only by hand action around the teeth. Alternatively the toothbrush may be a powered toothbrush provided with an internal motor to drive the bristles relative to the handle. Such a toothbrush may be of generally well-known conventional construction.

The bristles may be made of conventional bristle materials for tapered and non-tapered bristles, for example Nylon or polybutylene terephthalate. The bristles may be tapered or end rounded by conventional methods such as mechanical abrasion or chemical erosion. As cut across their bristle direction the tufts of bristles, whether containing tapered bristles or not, may be circular in section or other shapes. For example one or more tufts, for example some or all of the outer tufts comprising tapered bristles, may have a section which is elongated in the longitudinal direction, e.g. oval or rounded cornered rectangular. Other parts of the toothbrush head and grip handle may also be made of conventional materials such as plastics materials for example polypropylene, and the handle may also include conventional grip-enhancing surface pad regions which may for example be made of thermoplastic elastomer. Numerous conventional types of grip handle are well known in the toothbrush art. One example of a suitable grip handle construction is for example disclosed in EP-A-O 336 641. The grip handle and other parts of the toothbrush may be made by entirely conventional techniques such as injection moulding, as is commonplace in the toothbrush art.

The invention will now be described by way of example only with reference to the accompanying drawings. Fig. 1 shows side views of a non-tapered bristle and a tapered bristle.

Fig. 2 shows a plan view of a first construction of toothbrush head of this invention.

Fig. 3 shows a cross section of the toothbrush head of Fig. 2 cut across the line A-A of Fig. 2. Figs. 4 and 5 show a plan view and cross sectional view of another construction of the toothbrush head of this invention.

Figs. 6 and 7 show a plan and sectional view of another construction of the toothbrush head of this invention.

Figs. 8 and 9 show plan views of other constructions of toothbrush heads of this invention.

Fig. 10 shows a side view of another construction of toothbrush heads of this invention.

Figs. 11 and 12 show a respective plan view and side view of another construction of the toothbrush head of this invention. Figs. 13 and 14 show a respective plan view and side view of an overall construction of a toothbrush of this invention provided with a head of this invention.

Referring to Fig. 1, a conventional non-tapered bristle 10 is shown in a schematic sideways view, extending in bristle direction "B" from the bristle surface 20 of a toothbrush head (not shown). Bristle 10 has substantially the same uniform cylindrical cross-section along its entire length from its lower end 1OA adjacent the bristle surface 20, to its upper end 1OB remote from bristle surface 20. The region 1OC immediately adjacent the extreme upper end, e.g. the uppermost 5% or less, is end-rounded in an irregular hemi-ellipsoidal shape. Fig. 1 also shows a conventional tapered bristle 30. The lower part 30A of this bristle 30, extending upwards from bristle surface 20 has a substantially uniform cylindrical cross section. The upper part 30B comprising the uppermost 30% of the length of the bristle 30 tapers in a shallow pointed conical shape.

Referring to Fig. 2, a toothbrush head 40 generally is shown in a plan view, being connected at its end 4OA to a toothbrush grip handle via a neck region 41 of the grip handle to thereby define a head 40 - grip handle 41 longitudinal direction L - L, and having a longitudinally opposite tip end 4OB. The head 40 is elongate in the longitudinal direction L - L and has a width direction W - W perpendicular to the longitudinal direction L - L. The head 40 has a flat planar bristle surface 42 from which plural tufts of bristles 43 (generally) extend in their bristle direction "B" perpendicular to the plane of the bristle surface 42, and to both the longitudinal direction L - L and to the width direction W - W, the view in Fig. 2 being downwards along the bristle direction "B". The plural tufts 43 each contains plural bristles.

The plural bristle tufts 43 are arranged in a pattern on the bristle surface 42 that comprises plural outer tufts 431 containing only tapered bristles (i.e. as shown 30 in Fig. 1), tufts 431 being arranged along the widthways opposite outermost sides of the pattern of tufts 43. Tufts 431 are arranged sequentially in a line (indicated by the dashed line linking them) substantially equidistant from the widthways edge 44 of the bristle surface 42. Widthways between the plural outer tufts 431 are arranged plural inner tufts 432 containing only non tapering bristles (i.e., as shown 10 in Fig. 1)

The tufts 43 are positioned in a conventional two-dimensional array on bristle surface 42 with the tufts 43 being ca. 2 - 3 mm apart from each other. As shown in Fig. 2 this layout is symmetrical about the longitudinal direction L - L and comprises rows of bristle tufts 44 oriented widthways in the direction W - W across the bristle surface 42.

Fig. 3 shows a cross section through toothbrush head 40, as cut along the line A - A of Fig. 2, extending in the widthways direction W - W across head 40. Fig. 3 shows that plural outer tufts 431 containing only tapered bristles are of a first greater length from their lower end adjacent to the bristle surface 42 to their upper end remote from bristle surface 42, and plural middle tufts 432 containing only non-tapered bristles are of a second lesser length, less than the first greater length.

In the toothbrush head shown in Figs. 2 and 3, the difference between the first greater length of tufts 431 and the second lesser length of tufts 432 is 1 - 5 mm, for example 2 - 4 mm. Typically the first greater length of tufts 431 is 10 - 12 mm.

In the head 40 of Figs. 2 and 3 the tufts of bristles 43 are fastened into the bristle surface by conventional small metal "anchors" (not shown).

Referring to Figs. 4 and 5, a second construction of toothbrush head 50 generally is shown in a plan view in Fig. 4, being connected at its end 5OA to a toothbrush grip handle via a neck region 51 of the grip handle to thereby define a head 50 towards grip handle 51 longitudinal direction L - L and having an opposite tip end 5OB. The head 50 is elongate in the longitudinal direction L - L and has a width direction W - W perpendicular to the longitudinal direction L - L. The head 50 has a bristle surface 52 from which plural tufts of bristles 53 (generally) extend in their bristle directions "B" perpendicular to the plane of the respective part of the bristle surface 52 from which they extend. Fig. 5 shows a longitudinal section view.

The head 50 of Fig. 4 and Fig. 5 has a known construction in which a section 54 of the head which is relatively closer to the end 5OA of the head 50 attached to the grip handle 51 is resiliency and flexibly linked at link 55 to a section 56 of the toothbrush head 50 which is relatively remote from the grip handle 51. The link 55 comprises a composite link region, as shown in Fig. 5, composed of a flexible plastics material link 57 integrally linking the sections 55,56 embedded in a surrounding flexible elastomer material 58 such as a thermoplastic elastomer. Such a head construction is for example disclosed in WO-A-97/07707 and WO-A-98/37788, and is present in known toothbrushes e.g. as sold under the present applicant's AQUAFRESH™ brand.

From the bristle surfaces 52 of both sections 55 and 56 extend bristle tufts 53 which are arranged in the pattern on the bristle surface comprising plural outer tufts 531 containing only tapered bristles and arranged along the widthways opposite outermost sides of the tuft pattern and being of a first greater length, with widthways between these plural outer tufts 531 being plural inner tufts 532 containing only non tapering bristles and being of a second lesser length. The view in Fig. 4 is downwards along the bristle direction "B" of the tufts 53 extending from section 54. The bristle surfaces 52 of the two sections 55 and 56 form an angle less than 180° relative to each other, typically around 170°.

Although the link between the head 40, 50 and the neck region 41,51 is shown as a rigid ling, it may alternatively be a flexible link of known type, for example as disclosed in WO-A-98/37788.

Referring to Figs. 6 and 7 this shows a toothbrush head 60 (overall). Head 60 is connected at its end 6OA to a toothbrush grip handle (not shown) via a neck region 61 of the grip handle to thereby define a head 60 - grip handle 61 longitudinal direction L - L and having a longitudinal opposite tip end 6OB. The head 60 is elongate in the longitudinal direction L - L and has a width direction W - W perpendicular to the longitudinal direction L - L. Head 60 comprises three longitudinally elongate sections 62,63,64 being two widthways oppositely disposed outer sections 62,64 with a middle section 63 disposed widthways between said outer sections 62,64 disposed widthways adjacent across the toothbrush head 60. Each section 62, 63, 64 is flexibly linked to the handle by a respective neck 611,612,613. Each of the sections 62, 63, 64 has a respective bristle surface 65, 66, 67 Fig. 7 shows a cross-section through the head 60 cut across the line A-A of Fig. 6.

Extending from the bristle surfaces 65, 67 of outer sections 62 and 64 are plural outer tufts 68 containing tapered bristles of the first greater length, and plural inner tufts 69 containing only non tapering bristles and being of a second lesser length. Extending from the bristle surface of middle section 63 are plural inner tufts 69 containing only non tapering bristles and being of a second lesser length.

Middle section 63 is longitudinally extended beyond the ends of the outer sections 62, 63 and is widened to form tip pad 610 having a bristle surface 611.

Extending from bristle surface 611 of tip pad 610 are plural outer tufts 681 containing only tapered bristles and arranged along the widthways opposite outermost sides of the tip pattern of tufts and around the end of the tip pad 610 remote from grip handle 61. Referring to Fig. 8, a plan view of one widthways side of a toothbrush head 80 is shown. The arrangement of outer bristles 81 (generally) on the bristle surface 82 is shown. The tufts 81 comprise tufts 81 A which contain tapered bristles and tufts 8 IB which do not contain tapered bristles. Tufts 8 IB may be of the first greater length or a greater or lesser length than this first greater length. The arrangement of the plural outer tufts 81 comprises tufts 81 A which contain tapered bristles alternating longitudinally with tufts 8 IB which do not contain tapered bristles. Plural tufts 83 contain non-tapered bristles and are of the second shorter length. The head 80 is connected to longitudinally adjacent neck region 84. Referring to Fig. 9, a plan view of one widthways side of a toothbrush head

90 is shown. The arrangement of outer bristles 91 (generally) on the bristle surface 92 is shown. In this arrangement plural outer tufts 91 containing tapered bristles are arranged such that each tuft 91 is substantially widthways equidistant from the adjacent edge 93 of the bristle surface. The plural outer tufts 91 are arranged such that different tufts 9 IA, 9 IB are widthways adjacent each other at different widthways distances (as measured to their centres) Dl, D2, Dl being greater than D2, from the adjacent edge 93 of the bristle surface. Plural tufts 94 contain non-tapered bristles and are of the second shorter length. The head 90 is connected to longitudinally adjacent neck region 95. Referring to Fig. 10 a side view of a toothbrush head 100 and the adjacent part of the neck region 101 is shown. Fig. 10 also shows that the longitudinal direction of the toothbrush is not a straight line, but the direction of the neck 101 is angled relative to the direction of the head 100, as is commonplace in toothbrushes. Overall the construction of the head 100 and neck 101 are identical to the corresponding head 90 and neck 91 of Fig. 9. Two widthways adjacent outer tufts 102, 103 containing tapered bristles are shown extending from bristle surface 104. The tufts 102, 103 are oriented to lean at a non-perpendicular angle to the bristle surface, such as at 75-85° to the bristle surface, leaning in the longitudinal direction so that their respective ends remote from the bristle surface are either longitudinally closer or further from the grip handle. As seen in Fig. 10 looking in the widthways direction the tufts 102,103 appear to cross in an X arrangement. The neck 101 connects the head 100 to grip handle 105. Referring to Figs. 11 and 12 these show a respective plan view looking down the bristle direction, and a side view looking widthways of a toothbrush head 110 of this invention. As can be seen, the general arrangement is similar respectively to Figs. 6 and 7, therefore only some distinctive features of this head 110 are described in detail. Note that for clarity only some of the tufts of bristles are shown.

The toothbrush head 110 has a construction in the form of three longitudinally elongate sections 111, 112, 113 disposed widthways adjacent across the toothbrush head 110 in the form of two widthways oppositely disposed generally crescent shaped outer sections 111, 113 with a generally oval middle section 112 disposed widthways between the outer sections 111, 113. Each section 111, 112, 113 is independently resiliency moveable relative to a widthways adjacent section. Each section 111, 112, 113 is flexibly linked to the toothbrush grip handle (not shown) by a respective flexible neck 114, 115, 116 so that the sections 111, 112, 113 may be resiliency bent out of a plane parallel to the longitudinal and width directions under the action of pressure on the bristles.

Plural outer tufts 117 containing tapered bristles of the first greater length are disposed on the two widthways oppositely disposed outer sections 111, 113. These tufts 117 have a section cut across their bristle direction which is elongate in the longitudinal direction L-L being a rounded cornered rectangular shape. Plural inner tufts 118 containing non tapering bristles and being of a second lesser length are disposed on the middle section 112.

The middle section 112 widens widthways at a region 112A close to the tip end 119 which is less than 50% or less of the longitudinal length of the middle section 112 distanced from the tip end 119, relative to a region immediately longitudinally adjacent thereto closer to the grip handle. This widening at 112A forms a concavity 120 between the end 112A of the middle section 112 and the part of the middle section immediately longitudinally adjacent nearer to the handle. The end 1 IA of an outer section 111 is shaped in a complementary shape to the concavity 120 so that this end 11 IA fits into the concavity.

The middle section 112 is in sliding contact with adjacent outer sections 111, 113.

Plural tufts 121 comprising tapered bristles also extend from the widened part 112A of the middle section 112 adjacent to the tip end 119 of the middle section such that these tufts are the tufts most longitudinally remote from the toothbrush grip handle.

The bristle surface 122, comprised of the respective bristle surfaces of the sections 111, 112, 113 is concave in the longitudinal direction, with its upper surface as seen in Fig. 12 gently concave curved. This causes the tufts 121 on the widened region 112A to be oriented so their ends remote from the bristle surface is closer to the grip handle than their ends closer to the bristle surface.

Referring to Figs. 13 and 14, a respective plan view and side view of an overall construction of a toothbrush of this invention provided with a head of this invention are shown. The toothbrush 130 overall comprises a head 131 which may be any of the above-described heads 40, 50, 60, 80, 110. The head 131 is connected to a grip handle 132 by a neck region 133 which may be any of the above-described neck regions 41, 51, 61, 83, 95, 114, 115, 116. The head 131, grip handle 132 and neck region are all arranged along a longitudinal direction L-L. The bristle surface 134 and the side surface 135 of the head 131 can be seen.

Claims

Claims.

1. A toothbrush head connected to or connectable to a toothbrush grip handle to thereby define a head - grip handle longitudinal direction, the head being elongate in the longitudinal direction and having a width direction perpendicular to the longitudinal direction, the head having a bristle surface from which plural tufts of bristles extend in a bristle direction, the bristles being arranged in plural tufts each of which contains plural bristles, the bristles comprising plural tapered bristles and plural non-tapered bristles; characterised in that the plural bristle tufts are arranged in a pattern on the bristle surface comprising plural outer tufts containing tapered bristles and arranged along the widthways opposite outermost sides of the tuft pattern and being of a first greater length, and widthways between the plural outer tufts being plural inner tufts containing non tapering bristles and being of a second lesser length.

2. A toothbrush head according to claim 1 , wherein all of the plural outer tufts contain tapered bristles.

3. A toothbrush head according to claim 1 or 2, wherein all tufts which contain tapered bristles are entirely composed of tapered bristles.

4. A toothbrush head according to claim 1, 2 or 3 wherein all of the outer tufts are of the first greater length.

5. A toothbrush head according to any one of claims 1 to 4, wherein all of the inner tufts contain non-tapered bristles.

6. A toothbrush head according to any one of claims 1 to 5, wherein all of the inner tufts are composed entirely of non-tapered bristles.

7. A toothbrush head according to any one of claims 1 to 6 wherein all of the inner tufts are of the second lesser length.

8. A toothbrush head according to any one of claims 1 to 7 wherein the outer tufts are arranged in a line substantially equidistant from the widthways edge of the bristle surface.

5 9. A toothbrush head according to any one of the preceding claims wherein tufts containing tapered bristles of the first greater length are located adjacent to the end of the bristle surface longitudinally remote from the grip handle.

10. A toothbrush head according to any one of the preceding claims wherein tufts0 containing tapered bristles of the first greater length are located adjacent to the position of the toothbrush head at which the head is to be connected to the grip handle.

11. A toothbrush head according to any one of the preceding claims wherein the S difference between the first greater length and the second lesser length is in the range 1 - 5 mm.

12. A toothbrush head according to any one of the preceding claims wherein the toothbrush comprises a unitary block of a plastic material into which the tufts are0 fastened.

13. A toothbrush head according to any one of claims 1 to 11 wherein the toothbrush head has a construction in which a section of the head which is relatively closer to the end of the head remote from the grip handle is resiliently and5 flexibly linked to a section of the toothbrush head which is relatively closer to the grip handle.

14. A toothbrush head according to any one of claims 1 to 1 1 wherein the toothbrush head has a construction in the form of three or more longitudinally0 elongate sections disposed widthways adjacent across the toothbrush head, each section being flexibly linked to the handle, and being in the form of two widthways oppositely disposed outer sections with at least one middle section disposed widthways between said outer sections, each section independently resiliently moveable relative to a widthways adjacent section, the plural outer tufts containing tapered bristles of the first greater length being disposed on the two widthways oppositely disposed outer sections, and the plural inner tufts containing non tapering bristles and being of a second lesser length being disposed on the at least one inner section.

I S. A toothbrush comprising a grip handle connected to a toothbrush head as claimed in any one of claims 1 to 14.