Note: Descriptions are shown in the official language in which they were submitted.
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Toothbrush
This invention relates to toothbrushes, particularly to hand held toothbrushes
having a novel bristle configuration.
S Toothbrushes generally comprise a head and a grip handle disposed along a
longinlllin~l axis. Bristles extend from a bri,tle 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 elongatedoval shape with the long axis of the oval across the longinl~in~l axis of the head.
Circular section tufts are somPtimes 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 inveMion
to provide a toothbrush having a novel bristle configuration which in part at least
solves this problem.
According to one form of this invention, a toothbrush has a head and a grip
handle disposed along a longihl~lin~l axis, with bristles exren-iing from a bristle face
of the head in a general bristle direction generally perpen-lielll~r to the longinl-lin~l
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 longinl~iin~l 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 longit~ in~l axis, with bristles extending from a bristle face of the
head in a general bristle direction generally perpendicular to the longinlrlin~l 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 longihltlin~l 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 shapQs in the tuft 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 longinlrlin~l axis, and one or more
tufts or cluslers which taper in a direction toward the longihl~lin~l axis.
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Examples of sectional shapes which taper in the above-described ways are
triangles, with an apex towards the longin-f1in~l 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 longinl~1in~l 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
longin--lin~l 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 perpen~lie--l~r 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 pointinginwardly to form a triangular cluster.
The above mentioned tapering sectional-shaped clusters may alternatively be
made up of tufts which have a conventi~n~l rounded shape, e.g made up into a
triangle shaped cluster. For example three or more circular section tufts may bearranged 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 lonsgin-~lin~l 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 a~iuL,l iate, 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 contac~ 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 enh~nee the cleaning effect. The said first tufts and
clusters tufts have the advantage of improved conformation to the concavity of the
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curve of the gumline where the teeth meet the gums, and the combination of thesetufts with tufts of other sectional shapes can enhance the cleaning effect, for
example if such other sectional shaped tufts are suited to clean other areas of the
tooth or gum surface, the gumline or interdental spaces.
Such tufts of other sectional shapes may be of a conventional circular section
shape, but in one such embodiment of this invention first tufts are combined with
tufts (termed herein "second tufts"), having a sectional shape across the general
bristle direction. which is elongated in a direction generally aligned with the
longin-tlin~1 axis. Examples of such shapes are rectangular or lozenge shapes
elongated in a direction generally parallel to the longin1~lin~1 axis.
At the end of the head extreme from the handle, there may be a rounded,
e.g. circular, oval or polygonal pattern of tufts for example in the form of a
polygon of tufts 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 im"gin~ry closed
curved line can be drawn through the tufts at the perimeter of the cluster, e.g
through the corners of a polygon.
In another embodiment the said first tufts may be combined with one or
more tufts (termed "fourth tufts") which have a sectional shape across the general
bristle direction which is longer in a direction generally perpendicular to the
longin-~lin~1 axis than along this axis. For example the shape may be an oval,
rectangular or lozenge shape elongated in a direction generally perpen~ r to thelongin1rlin~1 axis.
Also, when two of t'ne said first tufts or clusters are arranged opposite each
other on opposite sides of the longit~1~lin~1 axis, between them, i.e. on or disposed
about the longin1~in~1 axis there may be one or more tufts situated between them.
In one embodiment of this invention the said first, second, third and fourth
tufts may be arranged on the toothbrush head in an arrangement comprising a
pattern of third tufts at the end of the head remote from the handle, then a sequence
of sets of first tufts evemy disposed on either side of the longin1-lin~1 axis optionally
with one or more fourth tufts between them, longin-~lin~11y alternating with a
pattern of second tufts. Suitably in this embodirnent there are first tufts
longin1~lin~11y adjacent to the third tufts, adjacent the base end of the head, and at or
near the longin1~7in~1 midpoint of the head.
In another embodiment of this invention the said first, second and third tufts
J may be arranged on the toothbrush head in an arrangement comprising a pattern of
third tufts 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 tufts, then sets of
first tufts of triangular section evenly disposed on either side of the longin1tlin~1
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axis, optionally with one or more fourth tufts between them, then a further sequence
of one or more rows of second tufts, then ad~acent the base of the head a further set
of first tufts of triangular section evenly disposed on either side of the longinldin~
axis.
In the above described embodimenrs the said first, second. third and fourth
tufts 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
lln~nl~tinsJ surface. Suitably the said first. and optionally also the said third, tufts
may be longer than the said second tufts.
The tufts of bristles, of all types, may be fixed into the toothbrush head by
conventional means, for example conventional small metal clips ret~ining them insocket 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 cl~iming priority thc.er,o-ll, the contents of which are inrl~ d herein
by way of reference), in which the head is made first with a first engagement part
and the handle is then forrned with a second engagement part in engagement with
the first engagement part.
The head and handle may include known r~aLulcs of toothbrushes, for
example elastomeric grip mats on the handle, and regions which modify flexibility,
for example folded regions or cut-outs com~ining an elastomeric material. The head
may have an nn~ ting 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 fil~mPn~c.
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 longit~ in~l axis A--A.
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From a bristle face 3 of the head 1 extend bristles 4, 5, 6, 7 arranged in
tufts. The view of Fig 1 (and Fig. 3) is down the general bristle direction B--B in
which the bristles extend.
Some of the tufts 4 are arranged in tufts which have a section, across the
general bristle direction, which is a right-angled triangle, with one of the right
angled sides generaliy perpendicular to the longinl~lin~l 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 outeredge. At about the longihl~lin~l mid-point along the edge, two such tufts on each
side of the longin--1in~1 axis A--A, 4A, 4B are arranged back-to-back to form anisosceles triangle. The triangular section tufts 4 are disposed such that one of their
edges lies at the outer edge of the tuft pattern, with an apex toward the longinlrlin~l
axis A--A.
~It~rn"ting with the triangular section tufts 4 is a pattern of second tufts 5,
which have a sectional shape, across their bristle direction, which is elongated in a
direction generally parallel to the longih-~1in"l axis A--A, being substantiallylozenge shaped.
At the end of the head 1 remote from the neck 2 are third tufts 6 in the form
of a polygonal pattern arranged around a central tuft.
Where some of the first tufts 4 are opposite each other across tne
longi~lin"l axis A--A there are fourth tufts 7 between them, on the lorlgihl-lin~l
axis A-A of the head 1, having a sectional shape across their bristle direction which
is elongated in a direction across the longit~l~in~l axis A--A, being of oval section.
As shown in Fig. 2 the first, third and fourth tufts 4, 6, 7 extend further
from the bristle face 3 than the second tufts 5, so that the surface in which the ends
of the bristles remote from the bristle face 3 is nn~ ting.
Referring to Fig. 3 an alternative construction of toothbrush head is shown,
in which features corresponding to the toothbrush of Figs 1 and 2 are
correspondingly numbered. In the toothbrush of Fig 3 the first tufts 8, 8A, 8B are
right angled triangle shaped in section across the bristle direction, but taper in a
direction away from the longinlflin~l axis A-A, such that the base of the triangle
faces the longitll~lin~l 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 tufts are arranged on the toothbrush head 1 in
an arrangement comprising a pattern of third tufts 6, in the form of a polygonalJ 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 tufts
5A. This is followed by a set of first tufts 4A of triangular section, in two clusters
each of three triangular sectioned tufts 4A, the section of each of which tapers in a
s
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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 longih~ n~l axis A-A. Then there is a further
sequence of rows of second tufts 5B. Then adjacent the base of the head 1 is a
5 further set of first tufts 4 of triangular seclion, in two clusters each of three
triangular sectioned tufts 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 longih--1in~l 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. Thetriangular sectional shape of the first tufts 4 and 8 enable the bristles in these tufts
to accomrnodate themselves better to the shape of the teeth, particularly the
gumline. The second, third and fourth tufts 5, 6 and 7 f~rilit~tP: cleaning of the
15 other areas of the teeth and the interdental spaces. The overall combination of tufts
on the toothbrush of the invention therefore results in an advantageous tooth
clP~ning effect.
