Oral care implement

Abstract

The present invention discloses a head (502) for an oral care implement (600), having a distal end (503) and a proximal end (504), said proximal end (504) connected or connectable to a handle (501), said head (502) having a mounting surface (510) with a longitudinal axis (AA) running along a length of the handle (501) and a transverse axis (BB) extending in a plane that is perpendicular to the longitudinal axis (AA), said mounting surface (510) having a central zone, a distal zone and a proximal zone, said mounting surface (510) having a tufting area MSA, said mounting surface comprising X number of bristle tuft holes (530), each bristle tuft hole (530) having a hole area TSA, wherein the bristle tuft hole (530) has a hexagonal cross-sectional area and wherein a ratio of the tufting area to a total hole area (MSA to X*TSA) is in the range of 1.5 to 3.1. The head according to the invention provides efficient cleaning of the buccal cavity with gentle feel.

Description

[0001] P0000913 CPL

[0002] 1

[0003] ORAL CARE IMPLEMENT

[0004] Field of the Invention

[0005] 5 The present invention relates in general to the field of oral care. More particularly, the present invention relates to a head for an oral care implement comprising hexagonal cross-sectional tufts for efficient cleaning while being gentle on teeth.

[0006] Background of the Invention

[0007] Different innovations in brush heads have been tried in the past to improve cleaning efficacy. For example, different arrangements of bristle patterns, different bristle materials, and different diameters / shape of bristles. However, most designs explored the most common circular or oval cross-sectional tufts.

[0008] 15 US 5850660 discloses a brush head having a plurality of tuft receiving holes, each of said tuft receiving holes having a hexagonal cross-section and a plurality of bristle bundles, each said bristle bundle having a portion positioned in and secured in a respective one of said tuft receiving holes, and each said bristle bundle having a plurality of hexagonal cross-section bristles, each said hexagonal cross-section bristle having opposite pairs of flat surfaces, said

[0009] 20 hexagonal cross-section bristles arranged in each said bundles such that a plurality of outwardly facing flat bristle surfaces about the periphery of said portion of each said bristle bundle within said respective tuft receiving hole are aligned and in frictional engagement with one of said flat inwardly facing surfaces of said tuft receiving hole side walls.

[0010] 25 US4617695A discloses a toothbrush having a brush handle and a brush head with a flat surface area, said brush head being provided with a plurality of openings to receive bristle bundles therein, the improvement comprising a plurality of openings each in the shape of a hexagon having parallel elongated sides and rounded opposing ends; said plurality of openings further being of a substantially uniform depth for receiving said bristle bundles.

[0011] Despite prior art, there is a need for a brush head which not only enhances cleaning efficacy but also provides soft feel to the consumers. At the same time, the manufacturing costs should not be high and brush head should be easy to produce.

[0012] 35 P0000913 CPL

[0013] 2

[0014] Summary of the Invention

[0015] In one aspect, the present invention discloses a head (502) for an oral care implement (600), having a distal end (503) and a proximal end (504), said proximal end (504) connected or connectable to a handle (501), said head (502) having a mounting surface (510) with a

[0016] 5 longitudinal axis (AA) running along a length of the handle (501) and a transverse axis (BB) extending in a plane that is perpendicular to the longitudinal axis (AA), said mounting surface (510) having a central zone, a distal zone and a proximal zone, said mounting surface (510) having a tufting area MSA, said mounting surface comprising X number of bristle tuft holes (530), each bristle tuft hole (530) having a hole area TSA, wherein the bristle tuft hole (530) has a hexagonal cross-sectional shape defined by opposite pairs of side walls which are parallel, each of the side walls providing a flat inwardly facing surface; wherein a ratio of the tufting area to a total hole area (MSA to X*TSA) is in the range of 1.5 to 3.1; and

[0017] 15 wherein each of the bristle tuft holes (530) comprises a plurality of bristles, each bristle with an end connected to the mounting surface and an opposite free end, said opposite free ends of the plurality of bristles comprised in the bristle tuft holes in the central zone collectively form a convex shaped distal surface when viewed from side in the direction of longitudinal axis (AA).

[0018] 20 In a preferred aspect, the ratio of MSA to X*TsAis in the range of 2.2 to 2.85

[0019] Preferably, the ratio of MSAto X*TSAis in the range of 1.5 to 2.8, more preferably 2.5 to 2.8.

[0020] The head in accordance with the invention allows for more efficient cleaning of the whole buccal

[0021] 25 cavity. The claimed dense arrangement of hexagonal bristle tuft holes not only ensures cleaning of the buccal cavity but also a softer feel desired by many consumers. The head according to the invention has a denser and flexible central zone with a desirable surface profile. At the same time, the claimed head is easy to manufacture with low costs. The head according to the invention provides lower soft tissue abrasion and provides a gentle feel to the consumers yet achieving the desirable cleaning.

[0022] Brief Description of the Drawings

[0023] Figure 1 is a top view of an oral care implement according to one aspect of the invention;

[0024] 35 Figure 2 is a top plan showing enlarged view of the head of the oral care implement according to the embodiment of Figure 1. P0000913 CPL

[0025] 3

[0026] Figure 3 is a top plan showing enlarged view of a head of an oral care implement according to a second alternative embodiment of the invention.

[0027] Figure 4 is a top plan showing enlarged view of a head of an oral care implement according to a

[0028] 5 third alternative embodiment of the invention.

[0029] Figure 5 is a top plan showing enlarged view of a head of an oral care implement according to a fourth alternative embodiment of the invention.

[0030] Figure 6 is a side view of the head of the oral care implement according to the first embodiment showing the surface profile.

[0031] Figure 7 is a close-up view of a section of the central zone of the head according to the embodiment shown in figure 2.

[0032] 15

[0033] Detailed Description of the Invention

[0034] As used herein the term “comprising” encompasses the terms “consisting essentially of” and “consisting of’. Where the term “comprising” is used, the listed options or components need not be exhaustive. Unless otherwise specified, numerical ranges expressed in the format "from x to

[0035] 20 y" are understood to include x and y. In specifying any range of values or amounts, any particular upper value or amount can be associated with any particular lower value or amount. Except in the examples or where otherwise explicitly indicated, all numbers are to be understood as modified by the word “about”. As used herein, the indefinite article “a” or “an” and its corresponding definite article “the” means at least one, or one or more, unless specified

[0036] 25 otherwise. The various features of the present invention referred to in individual sections above apply, as appropriate, to other sections mutatis mutandis. Consequently, features specified in one section may be combined with features specified in other sections as appropriate. Any section headings are added for convenience only and are not intended to limit the disclosure in any way. The invention is not limited to the embodiments illustrated in the drawings.

[0037] Accordingly, features mentioned in the claims if followed by reference numerals, such numerals are included solely for the purpose of enhancing the intelligibility of the claims and are in no way limiting to the scope of the claims. The examples are intended to illustrate the invention and are not intended to limit the invention to those examples per se. P0000913 CPL

[0038] 4

[0039] Terms such as ‘attached’, ‘anchored’ ‘connected’, ‘connectable’, ‘mounted’ and similar refer to a relationship where one structure is secured to another both by movable or rigid attachments or relationship, either directly or indirectly and should not be construed as limiting as per the described aspects of the invention.

[0040] 5

[0041] The present invention describes a head (502) for an oral care implement (600), having a distal end (503) and a proximal end (504), said proximal end (504) connected or connectable to a handle (501), said head (502) having a mounting surface (510) with a longitudinal axis (AA) running along a length of the handle (501) and a transverse axis (BB) extending in a plane that is perpendicular to the longitudinal axis (AA), said mounting surface (510) having a central zone, a distal zone and a proximal zone, said mounting surface (510) having a tufting area MSA, said mounting surface comprising X number of bristle tuft holes (530), each bristle tuft hole (530) having a hole area TSA, wherein the bristle tuft hole (530) has a hexagonal cross-sectional shape defined by opposite

[0042] 15 pairs of side walls which are parallel, each of the side walls providing a flat inwardly facing surface; wherein a ratio of the tufting area to a total hole area (MSA to X*TSA) is in the range of 1.5 to 3.1 ; and wherein each of the bristle tuft holes (530) comprises a plurality of bristles, each bristle with an

[0043] 20 end connected to the mounting surface and an opposite free end, said opposite free ends of the plurality of bristles comprised in the bristle tuft holes in the central zone collectively form a convex shaped distal surface when viewed from either side in direction of the longitudinal axis (AA). Preferably, the ratio of MSAto X*TSA is in the range of 2.2 to 2.85, preferably 2.5 to 2.8.

[0044] 25 Oral care implement means and includes all implements for oral care. It is preferred that the implement is a manual toothbrush, electronic toothbrush, tongue cleaner or an interdental brush. Depending on the purpose and application of the oral care implement the present invention could be used on the head of any kind of oral care implement. Any kind of handle useful as an oral care implement could be attached to the head of the present invention. When replaceable, the head is usually connected to the handle through a neck part. In a preferred aspect, the head, the neck part, the handle part are formed integrally as a single unit.

[0045] Referring to Figure 1 , a top view of an oral care implement, particularly a toothbrush (600) is illustrated according to one embodiment of the invention. The toothbrush (600) generally

[0046] 35 comprises a handle (501) and a head (502). The head (502) has a distal end (503) and a proximal end (504) (not shown in figure 1). The proximal end of the head (504) is the end which P0000913 CPL

[0047] 5 is connected or connectable to the handle (501) and distal end (503) is the opposite end. Without limiting to the one shown in figure 1, the handle of the oral care implement may have a wide variety of shapes and designs. It may be oval, round, flat, elliptical, or elongated shape.

[0048] 5 In the embodiment shown in Figure 1, the head, the handle part and the neck part are formed together as an integral unit to make the toothbrush (600) using injection molding. In alternative aspects, the handle (501) and the head (502) can also be manufactured separately as components and can be connected at a later stage in manufacturing using any known technique, including but not limiting to thermal welding, sonic welding, a tight-fit assembly, a coupling sleeve, adhesion, insert molding or fasteners. Furthermore, other manufacturing techniques may be used in place of and / or in addition to injection molding to create the handle (501) and / or the head (502) (or components thereof), such as milling and / or machining.

[0049] 15 Figure 2 is a top plan view showing enlarged front face of the head (502) of the oral care implement (600) according to the embodiment of figure 1. In this figure, shown is a head (502) having a distal end (503) and a proximal end (504), the proximal end connected or connectable to a handle. The head (502) of the oral care implement (600) has a mounting surface (510) and a rear surface (512) (not shown in figures) positioned opposite the mounting surface and one or

[0050] 20 more lateral surfaces (513). The mounting surface (510) may also be called as front surface, also being on that face of the handle, where the thumb is placed during use. The rear surface is accordingly the face lying opposite. The rear surface of the head may or may not have tongue cleaning elements. The lateral surfaces (513) are the surfaces which are visible when viewed sideways, i.e. , the surfaces appearing in between the mounting and the rear surface. A

[0051] 25 longitudinal axis (AA) runs along the head and in the direction of the length of the handle. The longitudinal axis (AA) is a reference line that is generally coextensive with the three-dimensional center line of the handle (501) and the head (502). The axis (AA) may be linear or non-linear. A transverse axis (BB) extends in a plane that is substantially perpendicular to the longitudinal axis (AA).

[0052] The mounting surface is divided into a proximal zone, distal zone and a central zone. The distal zone is the zone near the distal end and the proximal zone is the zone near the proximal end. The central zone is the zone lying between the proximal zone and the distal zone. In an aspect, the central zone extends from about 15 to 40 % from a point P towards each of the proximal

[0053] 35 end and the distal end. Point P is formed by intersection of axis AA and BB, when axis BB passes roughly through the centre of the head or mounting surface, i.e., at a point equidistant P0000913 CPL

[0054] 6 from the proximal and the distal end and when AA passes through the centre of the head or mounting surface in the direction of the length of the handle. According to this aspect, if the head or the mounting surface is considered to have a tufting area MSA, about 30-80% of the tufting area MSA in the centre (extending 20-40% from Point P towards each of proximal zone

[0055] 5 or distal zone) forms the central zone.

[0056] In an embodiment, Point P is formed by intersection of a centre or mid-point of the major axis and a centre or mid-point of the minor axis that cross the mounting surface.

[0057] Preferably, the central zone extends from about 20-40% from point P towards each of the proximal and the distal end.

[0058] More preferably, the central zone extends from about 20-30% from point P each towards proximal and distal zones, with the central zone being about 40-60% of the tufting area MSA.

[0059] 15 In the embodiment shown in figure 2, the bristle tuft holes (530) are arranged in 15 transverse rows. The transverse rows in the central zone (7) are arranged in a manner where one transverse row is transversely offset from another adjacent row to form a honeycomb pattern in the central zone. The other 8 rows (4 each in the distal zone and proximal zone) are arranged in a manner where each row is either parallel or offset from adjacent transverse row. As can be

[0060] 20 seen from figure 2, in the central zone, the bristle tuft holes (530) are arranged in rows that are transversely offset from the adjacent row forming a honeycomb pattern.

[0061] Figures 3-5 show other alternative embodiments according to the invention, where heads (502) of approximate sizes of 270 mm sq ± 5 mm sq, 310 mm sq ± 5 mm sq, and 195 mm sq ± 5 mm

[0062] 25 sq are shown.

[0063] Each of these embodiments show bristle tuft holes (530) which have a hexagonal cross- sectional shape defined by opposite pairs of side walls which are parallel, each of the side walls providing a flat inwardly facing surface.

[0064] Figure 6 shows a side view of the head (502) of the oral care implement according to the first embodiment showing the surface profile of the bristles.

[0065] In an aspect, the surface profile of the bristles mounted in the bristle tuft holes with hexagonal

[0066] 35 cross-section is not flat throughout the mounting surface. P0000913 CPL

[0067] 7

[0068] According to the invention, each of the bristle tuft holes (530) comprises a plurality of bristles, each bristle with an end connected to the mounting surface and an opposite free end, said opposite free ends of the plurality of bristles comprised in the bristle tuft holes in the central zone collectively form a convex shaped distal surface when viewed from side in the direction of

[0069] 5 longitudinal axis (AA). In an aspect, the distal surface is convex shaped when viewed from left side or right side in the direction of AA.

[0070] Preferably, each of the bristle tuft holes (530) has a plurality of bristles with an end connected to the mounting surface and an opposite free end, wherein the opposite free ends of the plurality of bristles in the X bristle tuft holes (530) together form a surface which is a waveform (in form of a wave) when viewed from either side in the direction of longitudinal axis (AA). One or more waveforms may be formed as seen from side on the whole of the mounting surface.

[0071] In the embodiment shown in Figure 6 but without limitation, the waveform has two sub-surfaces

[0072] 15 5301 , one each at the proximal and distal zones of the head and one sub-surface 5300 in the central zone.

[0073] In the embodiment shown in figure 6, without limitation, the sub-surface 5301 has an arc radius of about 13 ± 1mm. In one aspect according to the invention, the arc radius of the sub-surface

[0074] 20 5301 can vary in the range of 5 to 30 mm preferably in the range of 10 to 25mm and more preferably in the range of 10 to 18mm.

[0075] In the embodiment shown in figure 6, without limitation, the sub-surface 5300 in the central zone has an arc radius of about 33 mm ± 1mm. In one aspect according to the invention, the

[0076] 25 arc radius in sub-surface 5300 can vary in the range of range of 16 - 38 mm, preferably 18-35 mm and more preferably 20-35 mm. Further, the height H of the bristles would vary as the surface forms a waveform.

[0077] According to the embodiment shown in Figures 2 and 6, the bristle tuft holes in each of the rows (7 transverse rows) in the central zone have bristles of varying heights such that when viewed from left or right side, the outer ends of the bristles mounted in the bristle tuft holes collectively form a convex shaped distal surface in the central zone. In the central zone, when moving in the direction of longitudinal axis AA starting from the distal end, the height of bristles in any one transverse row would progressively first increase, form an apex and then progressively

[0078] 35 decrease when moving towards the proximal end. For example, the centermost row in the head P0000913 CPL

[0079] 8 would be higher as compared to the transverse row on its distal end and the transverse row on its proximal end.

[0080] This ensures optimum engagement with tooth surfaces without a feeling of hardness on tooth

[0081] 5 surfaces.

[0082] Shown in figure 7 is a close-up view of a section of the central zone of head according to figure 2. Any one bristle tuft hole (530) is separated from another adjacent bristle tuft hole (530) by a linear distance R when calculated from a centre point T of any bristle tuft hole (530). RAA is the distance R between any two bristle tuft holes when measured in direction of axis AA and RBB is the distance between any two adjacent bristle tuft holes as measured in direction of axis BB (RBB). The bristle tuft hole also has a perimeter P (not shown in figure). In the embodiment shown in figure 7, but without limitation, RAA varies in range of 1.9 - 2.7mm and RBB varies in range of 2.40 - 2.7 mm.

[0083] 15

[0084] It is to be noted that for ease of understanding, the bristle tuft holes (530) are shown largely similar in size in figures, but they may not necessarily be of same size, shape and contour as those shown in figures.

[0085] 20 Head

[0086] The head (502) of the oral care implement (600) includes cleaning elements or bristles either attached directly to the head or through a head plate. While the bristles shown in the figures is suited to be used with a toothbrush, it is to be understood that structural and functional modifications may be made without departing from the scope of the present invention and the

[0087] 25 invention may be embodied into any kind of oral care implements, for example such as those used to clean oral soft tissue, such as a tongue, gums, or cheeks. The bristles can be connected to the head (502) in any manner known in the art. For example, anchor free tufting (AFT), direct molding or staple technology. In a preferred aspect, staple technology is used to manufacture the head (502) of the toothbrush (600) which is formed as an integral unit with the handle (501).

[0088] Covered within the scope is any shape of the head (502). Preferably, the head (502) is noncircular with a major axis running along the longitudinal axis (AA) along the length of the handle and minor axis being transverse to the longitudinal axis along the axis (BB). Preferably, the

[0089] 35 head is oval, boat shaped, elliptical or rectangular with rounded ends. P0000913 CPL

[0090] 9

[0091] The mounting surface (510) is the surface of the head on which the bristles are mounted or attached to the head directly or indirectly. The mounting surface (510) can be present directly on the head (502) of the oral care implement or the mounting surface can be on a separate plate attachable to the head of the oral care implement. The bristles are generally anchored to

[0092] 5 the mounting surface and have an anchored end and an opposite free end. The opposite free end, away from the mounting surface forms the surface profile of the head. The head (502) and the mounting surface (510) are generally of different or similar contours, preferably of same shape but they can be different as well. The mounting surface has a tufting area MSA which is the total area available for tufting of bristles in the bristle tuft holes. This is generally calculated by calculating the perimeter of the head or the head plate depending upon the area available for planting the bristles.

[0093] In one aspect, the mounting surface has a tufting area MSA in the range of 150 mm sq to 450 mm sq, preferably 190 mm sq to 400 mm sq, more preferably 195mm sq to 395mm sq. The

[0094] 15 mounting surface comprises a plurality of hexagonal bristle tuft holesEach hexagonal bristle tuft hole has a hole area TSA in the range of 1.1 to 3.5 mm sq, preferably 1.7 to 3 mm sq., more preferably 1.7 to 2.7 mm sq.

[0095] According to one aspect of the invention, the head or mounting surface has X number of bristle

[0096] 20 tuft holes, wherein X is in the range of 20 to 70, preferably 30 to 65 bristle tuft holes, more preferably 32 to 60 bristle tuft holes.

[0097] In yet another aspect, the ratio of tufting area MSA to X * TSA is in a range of 1.5 to 3.1, preferably 2.2 to 2.85, more preferably 2.5 to 2.8.

[0098] 25

[0099] Further, any one bristle tuft hole is at a distance R from another adjacent bristle tuft hole, where R is not more than 3 mm, preferably not more than 2.8 mm, more preferably not more than 2.7 mm. Preferably, R is in the range of 1 mm to 4 mm, more preferably 1.5 mm to 3 mm, most preferably in the range of 1.9 mm to 2.7 mm.

[0100] In one aspect, the distance R between any two bristle tuft holes when measured in direction of axis AA (RAA) is equal to or less than the distance between any two adjacent bristle tuft holes as measured in direction of axis BB (RBB). In one aspect, RBB is in the range of 2.40 - 2.7mm. In another aspect, the distance RAA is in the range of 1.9 - 2.7mm. The bristle tuft holes may not

[0101] 35 be necessarily equidistant from each other in the axis AA or axis BB direction. P0000913 CPL

[0102] 10

[0103] The tufting area MSA, hole area TSA, the distance R are calculated by commercially available CAD software.

[0104] In one aspect, the bristle tuft holes are arranged in plurality of transverse rows that extend

[0105] 5 substantially perpendicular to the axis AA, wherein each transverse row is either parallel to its adjacent row or transversely offset from its adjacent row.

[0106] According to one aspect of the invention, the plurality of bristle tuft holes together occupy a tufted area which is at least 30% of the tufting area MSA of the mounting surface (510), preferably 35% and more preferably at least 37%.

[0107] According to another aspect, the plurality of bristle tuft holes together occupy a tufted area which is in the range of 30 to 50% of the tufting area MSA of the mounting surface (510), preferably 35% to 45%, more preferably 37% to 45%.

[0108] 15

[0109] The invention contemplates regular or irregular hexagonal cross-sectional bristle tuft holes. In addition to hexagonal bristle tuft holes, there could be other types of bristle tuft holes (other polygons or circular) present in the same head. The hexagonal cross-sectional bristle tuft holes can have any kind of vertices such as elongated, pointed vertices, rounded vertices. In one

[0110] 20 aspect, the hexagonal bristle tuft hole is irregular, where two opposing sides of hexagon are aligned in direction of the axis AA are larger in length as compared to the remaining sides. In a preferred embodiment, each bristle tuft hole on the head has a hexagonal cross-section.

[0111] As may be understood by person skilled, reference to ‘hexagonal bristle tuft hole’ throughout

[0112] 25 the specification implies a bristle tuft hole with hexagonal cross-section. The hexagonal bristle tuft hole comprises a hexagonal cross-section defined by opposite pairs of side walls which are parallel, each of the side walls providing a flat inwardly facing surface. Each of the opposite pairs of sidewalls of each of said hexagonal bristle tuft hole have first ends and second ends respectively, said first ends define an opening for the bristles, said second ends define a bottom wall where said bristles are engaged with the mounting surface. The hexagonal bristle tuft hole will also comprise a major diameter and a minor diameter.

[0113] In one aspect of the invention, each bristle tuft hole comprises number of bristles Y, wherein Y is in range of 18 to 40, preferably, 20 to 35, more preferably 23 to 30.

[0114] 35 P0000913 CPL

[0115] 11

[0116] In one aspect, the hexagonal bristle tuft holes are arranged in plurality of transverse rows that extend substantially perpendicular to the axis AA, wherein each transverse row is either parallel to its adjacent row or transversely offset from its adjacent row. Preferably, the transverse rows in the central zone are transversely offset from its adjacent row on each side to form a

[0117] 5 honeycomb pattern. In another aspect, the transverse rows in the distal and the proximal zone are either parallel or transversely offset from the adjacent row.

[0118] In one aspect of the invention, any one bristle of the plurality of bristles is connected to mounting surface or head in either perpendicular direction or at an angle. Preferably, the angle is in the range of 0 to 16 degrees, preferably, 4 degrees to 16 degrees, more preferably from 4 degrees to 8 degrees.

[0119] In one aspect according to the invention, the central zone comprises a plurality of bristle tuft holes having hexagonal cross-sectional shape, each of the bristle tuft holes (530) comprising a

[0120] 15 plurality of bristles with an end connected to the mounting surface and an opposite free end, wherein the opposite free ends of the plurality of bristles in the bristle tuft holes in the central zone together form a convex shaped distal surface when viewed from side.

[0121] As seen in Fig 6, the distal surface 5300 is convex in longitudinal side profile, the longitudinal

[0122] 20 side profile being the profile seen from left or right side when viewed in the direction of the axis A-A. The distal surface in transverse side profile along B-B may be flat or convex. Preferably, the longitudinal side profile is convex, and the transverse side profile is flat or convex. In another preferred aspect, the longitudinal side profile is convex, and the transverse side profile is flat. In yet another preferred aspect, the longitudinal side profile is convex, and the transverse

[0123] 25 side profile is convex.

[0124] Furthermore, in the exemplified embodiment the distal surface 5300 is an uninterrupted surface that is free any opening. Thus, the distal surface 5300 is a continuous surface that has no breaks, holes, openings, or the like therein (other than the normal and natural spacing that might exist between individual bristles in a bristle tuft and between any two bristle tufts).

[0125] In a preferred embodiment, height of bristles vary in bristle tuft holes as they travel from the proximal end to the distal end along the axis AA, but the peak height remain same in any one transverse row along the axis BB.

[0126] 35 P0000913 CPL

[0127] 12

[0128] In another aspect, the opposite free ends of the plurality of bristles in each of the distal and / or the proximal zone form a surface profile which is sloping down towards the central zone. Preferably, the opposite free ends of the plurality of bristles in the proximal zone form a surface profile which slopes down towards the central zone and the opposite free ends of the plurality of

[0129] 5 bristles in the distal zone form a surface profile which slopes down towards the central zone.

[0130] In one aspect, each of the bristle tuft holes (530) has a plurality of bristles with an end connected to the mounting surface and an opposite free end, wherein the opposite free ends of the plurality of bristles in all the X bristle tuft holes (530) together form a surface on the mounting surface or head which is a waveform when viewed from side. The waveform has one or more crests and two or more troughs.

[0131] Bristles type and material

[0132] Any material suitable for making the bristles is within the scope of the invention. In one aspect,

[0133] 15 the bristles are made from synthetic or natural materials. In an aspect, the bristle material is selected from nylon, polybutylene terephthalate (PBT), polypropylene (PP), Polyethylene terephthalate (PET), Boar bristles, Bamboo fiber bristles, Silicone bristles, polylactic acid (PLA), rubber, Thermoplastic elastomer (TPE) and / or combinations thereof. The bristles could be of any diameter suitable for making oral care implements. In a preferred aspect, the bristles are

[0134] 20 made from nylon or PBT or combination of either of two with any other material.

[0135] Further, any kind of cross section of the bristles is under the purview of the invention. The bristles could be circular or any non-circular in cross-sectional shape. Moreover, the bristles in each of the tufts can be round-end, multi-tip, tapered, profile bristles (square, dual core, spiral,

[0136] 25 star, dumbbell etc.) or a combination thereof.

[0137] As may be understood by a person skilled, bristles are generically called bristles and could also be called alternatively as cleaning elements, filaments, or teeth cleaning elements. Any structure that can be used in head of oral care implements to clean could be called bristles.

[0138] Method of manufacture

[0139] All parts of the oral care implement, particularly toothbrush according to the invention are either unitarily constructed together from an identical material or constructed separately from different materials. Preferably, the head of the oral care implement is unitarily formed with the handle by

[0140] 35 injection moulding technique. P0000913 CPL

[0141] 13

[0142] The bristles are planted on the head either directly via tufting or through a separately tufted head plate by techniques known in the art such as anchor free technology, PTt (Pressure tufting), staple technology etc. Preferably, the bristle tuft holes are also made by the injection moulded technology to which the bristles are then mounted via the anchor free or direct staple

[0143] 5 technology.

[0144] The present inventors have found that hexagonal bristle tuft holes provide better cleaning and better plaque removal benefits as compared to circular tufts without increasing the size of the head. This helps to design smaller heads with yet improved cleaning efficacy. The toothbrush according to the invention also has soft feel for consumers.

[0145] Toothbrush according to one embodiment of the invention is described herein below. Such an embodiment is not limiting on the scope of the invention.

[0146] 15

[0147] The overall length of the toothbrush (600) is about 192 mm ± 5 mm. The handle and head is made of Styrene acrylonitrile (SAN) and the bristles are mounted using staple technology. In the embodiment described herein, the bristles are made of Nylon. A head is designed to be of about 390.15 ± 5 mm sq. The head which is also the mounting surface in this example has 59 ±

[0148] 20 2 bristle tuft holes which are hexagonal. Each hexagonal bristle tuft hole is approximately 2.49 mm sq ± 0.5 in size.

[0149] The implement in accordance with the invention provides a denser head, better cleaning and softer feel to consumers.

[0150] Example 2 - Comparison of examples according to the invention with marketed toothbrush The present invention was compared with a marketed toothbrush to find out the ratio of MsAto

[0151] X*TSAand the results are shown in table A below.

[0152] 30 P0000913 CPL

[0153] 14

[0154] Table A

[0155] 5 Clearly, the hexagonal bristle tuft holes allow more denser packing of the head as compared to circular tufts. Lower the ratio of MsAto X*TsA,the higher is the head tuft density. An optimally packed head provides improved cleaning and freshness feel to consumers. The present inventors also found that combining hexagonal cross-sectional tufts with a convex shaped distal surface profile instead of a flat surface profile further provides benefits in cleaning, foaming and 10 freshness feel for consumers as well as reducing abrasion on teeth.

Claims

P0000913 CPL15CLAIMS1. A head (502) for an oral care implement (600), having a distal end (503) and a proximal end (504), said proximal end (504) connected or connectable to a handle (501), said head (502) having a mounting surface (510) with a longitudinal axis (AA) running along a length of the handle (501) and a transverse axis (BB) extending in a plane that is perpendicular to the longitudinal axis (AA), said mounting surface (510) having a central zone, a distal zone and a proximal zone, said mounting surface (510) having a tufting area MSA, said mounting surface comprising X number of bristle tuft holes (530), each bristle tuft hole (530) having a hole area TSA, wherein each of the bristle tuft hole (530) has a hexagonal cross-sectional shape defined by opposite pairs of side walls which are parallel, each of the side walls providing a flat inwardly facing surface; wherein a ratio of the tufting area to a total hole area (MSA to X*TSA) is in the range of 1.5 to 3.1 ; and wherein each of the bristle tuft holes (530) comprises a plurality of bristles, each bristle with an end connected to the mounting surface (510) and an opposite free end, said opposite free ends of the plurality of bristles comprised in the bristle tuft holes (530) in the central zone collectively form a convex shaped distal surface when viewed from side in direction of the longitudinal axis (AA).

2. The head (502) according to claim 1 , wherein the ratio of MSAto X*TSA is in the range of 1.5 to 2.8.

3. The head (502) according to any of claims 1-2, wherein the tufting area MSA is in a range of 150 mm sq to 450 mm sq, preferably 190 mm sq to 400 mm sq, more preferably 195 mm sq to 395 mm sq.

4. The head (502) according to any of preceding claims, wherein the hole area TSA is in a range of 1.5 to 3.5 mm sq, preferably 1.7 to 3 mm sq., more preferably 1.7 to 2.7mm sq.

5. The head (502) according to any of the preceding claims, wherein any one bristle tuft hole (530) is at a distance R from adjacent bristle tuft hole (530), where R is not more than 3 mm, said R being calculated from a centre point T of the bristle tuft hole (530).P0000913 CPL166. The head (502) according to claim 5, wherein R when measured in direction of axis AA (RAA) is equal to or less than R when measured in direction of axis BB (RBB).

7. The head (502) according to any of the preceding claims wherein the hexagon bristle tuft hole (530) is irregular, where two opposing sides of hexagon which are aligned in direction of the axis AA are larger in length as compared to the remaining sides.

8. The head (502) according to any of the preceding claims, wherein the bristle tuft holes (530) are arranged in plurality of transverse rows that extend substantially perpendicular to the axis AA, wherein each transverse row is either parallel to its adjacent row or transversely offset from its adjacent row.

9. The head (502) according to claim 8, wherein the transverse rows in the central zone are transversely offset from its adjacent row on each side to form a honeycomb pattern.

10. The head (502) according to claims 8 or 9, wherein the transverse rows in the distal and the proximal zone are either parallel or transversely offset from the adjacent row.

11. The head (502) according to any of claims 1-10, wherein each of the bristle tuft holes (530) has a plurality of bristles with an end connected to the mounting surface and an opposite free end, wherein the opposite free ends of the plurality of bristles in the X bristle tuft holes (530) on the mounting surface together form a distal surface which is a waveform when viewed from side.

12. The head (502) according to any of the preceding claims, wherein any one bristle of the plurality of bristles is connected to mounting surface in either perpendicular direction or at an angle of 0 to 16 degrees.

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