TOOTHBRUSH AND METHOD FOR MAKING A TUFT OF BRISTLES USABLE IN A TOOTHBRUSH

Abstract: A toothbrush (98) includes a handle (100), a head (102) extending from the handle and a tuft (104) of bristles which are joined together at a base end of the bristles and secured to the head at the base end. The tuft has a width and a length. A ratio of the width to the length is about 0.25 or less.

Description: TOOTHBRUSH AND METHOD FOR MAKING A TUFT OF BRISTLES USABLE IN A TOOTHBRUSH The invention relates generally to the field of oral care, and in particular to toothbrushes. The invention also relates to a method of making a tuft of bristles which are usable in a toothbrush. In a traditional manufacturing process for making toothbrushes, a tuft of bristles is "picked" from a large supply of pre-cut bristles. The tuft of bristles is then stapled to a head of a preformed handle/head of a toothbrush. The free ends of the bristles are end-rounded and then the toothbrush is packaged for shipment. A more recently developed process for making toothbrushes requires that the picked tuft is heat-fused at one of its ends to melt the bristle ends together and thus secure the bristles together. A large number of fused tufts are then placed in a toothbrush handle/head mold of an injection molding machine, with the fused ends of the tufts protruding into the mold and the remaining portion of the tuft being located outside of the mold. Molten plastic is next injected into the mold cavity. When the plastic solidifies, it secures the fused ends of the tufts to the head of the just-formed toothbrush. In this process, the bristles can be end-rounded either before or after they are secured to the toothbrush head. In both of the toothbrush manufacturing processes described above, the variation allowed in the dimensions of an individual tuft in the two axes of the tuft which are perpendicular to each other and the long axis of the bristles has been limited. For example, traditional tufts are round in shape, and for those tufts which are other than round in shape, the dimension of the tuft along a first axis which is perpendicular to the long axis of the bristles will typically be no greater than two to three times the length of a dimension of the tuft along a second axis which is perpendicular to the first axis and the long axis of the bristles. Such a limitation on the dimensions of a tuft reduces the variety of tuft shapes which can be incorporated into a toothbrush, thus inhibiting the design of a toothbrush which otherwise might provide improved cleaning of the teeth. A further drawback with currently known methods of making toothbrushes is that the only characteristic of the bristles within a tuft which varies from one bristle to another is bristle length. Other characteristics of the bristles within a tuft, such as material, color, gray scale, surface characteristic and cross-sectional shape, do not vary. As a result, the visual appearance and cleaning effectiveness of tufts, and thus toothbrushes, is correspondingly limited. A still additional restriction in current toothbrushes and their manufacture, is that the positioning of a bristle within a tuft relative to another bristle in that tuft is completely random. This is due to the fact that all of the bristles in a tuft are typically "picked" at one time in a single operation. Not being able to control the positioning and/or orientation of a bristle in a tuft relative to one or more other bristles in the same tuft restricts the capability of controlling tuft visual appearance and cleaning ability. U.S. Patent No. 4,366,592 which issued on January 4, 1983 to Bromboz, discloses brushes and the method of making the same by first forming a strip embodying a backing sheet with bristles disposed on one face thereof in parallel relation to each other. Ends of the bristles project outwardly from one longitudinal edge of the strip. The strip is formed into a predetermined shape and then the bristle ends are secured in a base. Finally, the backing sheet is removed from the bristles. The present invention is directed to overcoming one or more of the problems set forth above. Briefly summarized, according to one aspect of the present invention, a toothbrush includes a handle, a head extending from the handle and a tuft of bristles which are joined together at a base end of the bristles and secured to the head at the base end. The tuft has a width and a length. A ratio of the width to the length is about 0.25 or less. The toothbrush described in the previous paragraph includes a tuft having a relatively small width to length ratio not disclosed in the prior art. Such a tuft expands the available tuft shapes available to toothbrush designers, thereby allowing a greater variety of toothbrush bristle patterns. According to another aspect of the invention, a toothbrush includes a handle, a head extending from the handle and a tuft of bristles which are joined together at a base end of the bristles and secured to the head at the base end. One of the bristles has a characteristic that is different from that characteristic of another one of the bristles, the characteristic being selected from the group consisting of material, color, gray scale, surface characteristic and cross-sectional shape. By providing a toothbrush with a tuft having bristles with different materials, colors, gray scales, surface characteristics and cross-sectional shapes, the appearance and cleaning ability of the tuft, and thus the toothbrush, can be enhanced. According to a third aspect of the invention, a toothbrush includes a handle, a head extending from the handle and a tuft of bristles which are joined together at a base end of the bristles and secured to the head at the base end. A first one of the bristles is located in the tuft in a predetermined position and/or orientation relative to a second one of the bristles. By enabling bristles to be located in predetermined positions and/or orientations within a tuft, the characteristics of the tuft, including appearance and tooth cleaning ability, can be controlled to a relatively fine degree based on the characteristics of the individual bristles. In accordance with a fourth aspect of the invention, a method of making a tuft of bristles for use in a toothbrush includes the step of positioning a group of individual bristles adjacent to each other such that the bristles are substantially parallel to each other in their longest dimension. The group of bristles has a width and a length. A ratio of the group width to length is about 0.25 or less. The method also includes the step of securing one portion of each bristle to one portion of at least one other bristle to form a tuft. These and other aspects, objects, features and advantages of the present invention will be more clearly understood and appreciated from a review of the following detailed description of the preferred embodiments and appended claims, and by reference to the accompanying drawings. FIG. 1 is a perspective view of a single bristle picker station; FIGs. 1 A and IB are top views of a picking wheel showing various notched circumferences of the wheel; FIG. 2 is a top view of a tuft manufacturing machine including a pair of bristle picker stations; FIG. 3 is a partial side view Of Fig. 2 along the direction of arrow X in Fig. 2; FIGs. 4A-C are perspective views of three types of bristle tufts; FIGs. 5A-C are side views of three tufts each having a different top contour; FIG. 6A-B are perspective views of two tufts with the bristle ends processed in two different manners; FIG. 7 is a looped bristle type of tuft; FIGs. 8A-C disclose steps for making round tufts; FIGs. 9A-D disclose steps for making round tufts and show a round tuft secured to a toothbrush head; FIG. 10 A-E discloses toothbrush heads with various types of tufts secured to the heads; FIG. 11 discloses another apparatus for making tufts; and, FIGs. 12A-B disclose tufts made by the apparatus of Fig. 11. Beginning with Fig. 1, a method and apparatus for manufacturing a tuft of bristles for use in a toothbrush will be described. A supply of bristles 10 are stored in a magazine 11. The bristles are, for example, preferably made of nylon or polyester. The bristles can also be made of polypropylene or a natural or synthetic material suitable for bristles. The bristles are preferably between about 12 to 37 mm long prior to being joined together, and have a preferable diameter of between about 0.1 to 0.25mm. Preferably, the bristles are pre-end-rounded at the ends showing in Fig. 1. All of the bristles 10 are preferably identical in material, length, cross-section, color and/or gray scale. A pneumatically operated pusher 22 presses bristles 10 against one or more picking wheels 12 with a force of preferably between about 9 to 18 psi. As shown in Figs 1A and IB, the circumference of wheel 12 is notched with each notch capable of holding a single bristle 10. The shape of each notch is selected to hold a particular type of tuft. Although all of the notches on a wheel preferably have the same shape, the spacing between notches can vary to allow varied spacing between picked bristles. The wheels 12 in Figs 1A and IB have notches which differ in shape between the two wheels, thus allowing each wheel to pick a different sized bristle. Turning to Fig. 2, a pair of picking wheels 12 are shown and are rotated in the direction of arrows 23 at the same constant speed by a variable speed drive system (not shown). Wheels 12 are preferably about 3 inches in diameter and are rotated at between about 3 to 30 rpm. Bristles 10 being fed to a first one of picking wheels 12 can be different in material, length, cross-section, color and/or gray scale from bristles being fed to a second one of the picking wheels. When bristles 10 are pressed against wheels 12 by pushers 22, those bristles at a nip point 24 between the wheel and bristles are captured by the notches in the circumference of the wheel and carried in the direction of arrows 23. Wheels 12 contact the bristles just below the mid-point of the bristle length. A pair of pinch plates 26 for each wheel 12 contain bristles 10 in magazine 1 1 and prevent those bristles captured in the wheel notches from falling out of the notches once the captured bristles are rotated away from the supply of bristles. Wheels 12 and pinch plates 26 are preferably made of hardened steel or carbide for wear resistance. As mentioned above, the notches on wheels 12 can have variable spacing between notches. This space can be very small to very large in size. Wheels 12 are constructed and rotationally aligned such that where the wheels nip together, the notches on one wheel face the spaces between notches on the other wheel and vice versa. As such, when wheels 12 are rotated, bristles 10 are "shuffled together" one after the other in a single layer at the nip between the wheels like a deck of cards. Because the spacing between notches is variable, a huge variety of bristle patterns of the bristles from the two wheels twelve can be obtained. For example, the bristles from each wheel can alternate in a one to one pattern, a two to one pattern, or any pattern desired. Further, any bristle in the finished tuft will be in a predetermined position and/or orientation relative to any other bristle in the tuft. Wheels 12 each carry their respective bristles to a nip of a pair of endless belts 13. Belts 13 are nonstretchable or are minimally stretchable, and are preferably made of plastic. The belts are rotated in the direction of arrows 28 by a pair of belt drive pulleys 14 which are powered by a variable speed drive system (not shown). A pair of belt tensioners 16 maintain a desired tension on belts 13. Two pairs of belt guide rollers 30 are located at both ends of where belts 13 nip together. The belts 13 are driven by pulleys 14 at the same constant speed which may be the same as, slower than or faster than the speed at which wheels 12 are rotated. At an end of the nip between belts 13 which is adjacent wheels 12. the belts capture the bristles from the nip of wheels 12 and carry them in the direction of arrow 28. The mid-point of where belts 13 contact bristles 10 is just above the mid-point of the bristle length. If belts 13 are moving faster than wheels 12, bristles 10 will have their spacing increased on the belts. If belts 13 are moving the same speed as wheels 12, bristles 10 will maintain their spacing on the belts. If belts 13 are moving slower than wheels 12, bristles 10 will have their spacing compressed on the belts. The bristles are preferably parallel to each other in their longest dimension at this point. It should be noted that although only two wheels 12 are disclosed for feeding two types of bristles to belts 13, additional wheels and belts can be added to feed additional types of bristles into belts 13. For example, an additional pair of belts (not shown), fed by an additional one or two picker wheels (not shown), would feed an additional one or two types of bristles to the nip point between wheels 12. These additional belts would be located above wheels 12 while the bristles being carried by these belts would have the majority of their length protruding below the additional belts. Wheels 12 would have spaces between their notches, which spaces would line up with each other, wherever the bristles from the additional belts were being introduced between wheels 12. A pair of belt guide plates 15 are in contact with belts 13 on either side of where the belts nip together. Each plate 15 is divided up into four sections A, B, C and D which can each be independently positioned closer to or further from the belt nip. By adjusting the position of each of the sections of plates 15, the pressure with which belts 13 nip bristles 10 can be adjusted in four zones of the nip between the belts. Preferably, the sections of plates 15 are positioned so that the nip pressure in zones A and D are relatively higher than the nip pressure in zones C and D. The reason for this pressure gradient will be explained below with reference to Fig. 3. Fig. 3 is a partial side view of Fig. 2 along the direction of arrow X in Fig. 2. Only bristles 10, the lower wheel 12 from Fig. 2 and the upper belt 13 of Fig. 2 are shown in Fig. 3 along with several new elements. Zones A, B, C and D as described above are also shown. The nip pressure of belts 13 in zone A is relatively high in order to secure bristles 10 and carry them away from wheels 12. In zone B the belt nip pressure is lowered so that a shaping element 32 (not shown in Fig. 2) can move some or all of bristles 10 along their long axis to provide a contour to the finished tuft. Element 32 is rotated in the direction of an arrow 34 at the same speed with which the bristles are traveling. Element is also moved up and down by a cam mechanism (not shown) in the direction of arrow 36. This rotation and translation of element 32 moves the bristles axially and provides the pattern shown in Fig. 3. Of course other types of shaping elements could be used to impart different contours to the bristles. A resistive hot air blower 38 includes a fan 40 which draws air into the blower and blows the air past an electrically resistive heating element 42 to heat the air to preferably well above the melting temperature of the bristle material. The heated air then passes through a duct 44 and is blown onto a portion 46 of bristles 10 to fuse the bristles together at that portion. It is preferable that hot air be blown onto portion 46 from both sides of the ribbon to speed fusing together of the bristles. The fused together bristles result in a bristle ribbon 49. Portion 46 of bristles 10 could alternatively be fused together by ultrasonic or laser welding, or adhered together by application of an adhesive and/or a resin (synthetic and/or natural) to both sides of portion 46. A cutter 48 then trims away the portion of bristles 10 from ribbon 49 which are below fused portion 46. Alternatively, cutter 48 can trim away the lower portion of the bristles prior to the bristles being fused together by blower 38 (version not shown in drawings). In this version, the relative positions of blower 38 and cutter 48 would be reversed, placing the cutter upstream of the blower. Blower 38 in this version blows hot air directly from below and onto the severed ends of the bristles. A second reciprocating cutter 50, which is reciprocated in the directions of an arrow 52, periodically cuts through fused portion 46 of the bristles to cut a tuft of bristles 54 free from ribbon 49. Tufts 54 are transported further in the direction of arrows 28 by pairs of nip rollers (not shown) for further processing. It should be noted that blower 38, and cutters 48, 50 are not visible in Fig. 2 because they are below plates 15. With reference to Figs. 4A-C, tufts 54a-c are shown. All of these tufts have flat contours on top contrary to the rounded top contour of tuft 54 in Fig. 3. The end rounded ends 56 of the bristles are visible in Figs. 4A-C. Regarding Fig. 4A, it is preferable that for tuft 54a, a ratio of the width to length "A"/"B" is about .25 or less. In Fig. 4B, a pair of tufts have been fused together to form a tuft 54b which is twice as wide as tuft 54a. The pair of tufts can be fused together by first aligning the tufts and then subjecting them to heat via impinging hot air, a laser or ultrasonic waves on portions 46 of the two tufts. Alternatively, the two tufts can be secured together with an adhesive and/or resin. In Fig 4C, tuft 54c is made up of three tufts which have been secured together. Note that a middle tuft 58 is taller than the two outer tufts. This displays that any number of three dimensional contours for the finished tuft can be obtained by controlling the contour and bristle length of the bristle ribbons. Alternatively to fusing together two or more tufts after severing the tufts from the bristle ribbon 49 as in 4B and C above, two or more bristle ribbons can be fused together first and then have individual tufts severed from the ribbon. This is accomplished by bringing the two or more bristle ribbons together in a desired alignment after each ribbon has been separately fused at its own portion 46, and then fusing together portion 46 from each of the ribbons by any of the fusing methods discussed above (i.e. ultrasonic, adhesive, resin). Then individual tufts 54 are cut away from the multi-layer bristle ribbon to form multi-layer tufts. Turning to Figs. 5A-C, three tufts, each having a different top contour, are displayed. Tuft 54a was discussed in the previous paragraph while tuft 54 was disclosed during the discussion of Fig. 3. Tuft 54d has a "V" shaped top contour. As shown in magnified portions 60, 60a and 60d of the top portion of some of the bristles in each of the tufts, bristles 10a and 10b are in an alternating pattern. Bristles 10a were fed from one picking wheel 12 (Fig. 2) while bristles 10b were fed from the other picking wheel. As mentioned above, bristles 10a can differ from bristles 10b in material, length, cross-section, color and/or gray scale. Although a one to one alternating pattern of bristles 10a and 10b is shown, any pattern of bristles may be formed based on the notch and space arrangement on the periphery of picker wheels 12. For example, there could be two 10a bristles for every one 10b bristle. Referring to Figs. 6A and B, multi-layer tufts 54e and 54f, similar to tuft 54c of Fig. 4C, are shown. In tuft 54e, ends 62 of a middle layer of bristles 64 have been processed into a "micro-pick" form. This processing is done by (i) heating ends 62 to near their melting temperature, (ii) clamping a small portion of ends 62 with a bar clamp (not shown), (iii) pulling the bar clamp away from the bristles in the direction of the long axis of the bristles to cause ends 62 to "neck down", (iv) cooling bristle ends 62, and (v) cutting free the small portion of ends 62 which are secured within the clamp. Tuft 54f of Fig. 6B includes a "micro-hook" at bristle ends 66. This micro-hook is formed by a similar process used to form the micro-pick with one additional step. The step occurs just before cooling step (iv) described above and consists of rotating the clamp about 180 degrees to bend bristle ends 62 as shown in Fig. 6B. The micro-pick and micro-hook provide enhanced cleaning near the interproximal zones of teeth and under the gum line (sub-gingival), each providing a different mouth feel. Referring to Fig. 7, a looped bristle type of tuft 68 is disclosed. Tuft 68 is formed by heat fusing a second portion 70 of bristles 10 together, portion 70 being located near the end of the bristles opposite the end near which portion 46 is located (see Fig. 46). The bristles are then bent in half to align fused portions 70 and 46 adjacent each other. Finally, portions 46 and 70 are heat fused together. Looped bristle tuft 68 provides improved stiffness and wear resistance. As a further optional processing step, the looped portion of the bristles can be heated to near their melting temperature and then pressed flat between two plates in order to flatten the looped portion of the bristles (not shown in drawings). Turning to Figs. 8A-C, a process for forming a round tuft from a tuft cut from a bristle ribbon will be described. In Fig. 8A a single layer tuft 72 is disclosed which has a "Length", a bristle height "HI" at the left end and a bristle height "H2" at the right end (the bristles on the right portion of the tuft above portion 46 are not shown). This arrangement results in a sloping contour of the bristles. In Fig. 8B tuft 72 is rolled up on itself to form a round tuft. Tuft 74 results if end "H2" is on the outside of the round tuft and end "HI" is on the inside (a convex tuft). Tuft 76 results if end "HI " is on the outside of the round tuft and end "H2" is on the inside (a concave tuft). Tuft 78 results if tuft 72 had a flat contour in that H1=H2 (a flat topped tuft). After tuft 72 is rolled up, portion 46 is again heat fused to secure portions 46 of the bristles together, thus locking the tuft into its rounded shape. In Fig. 8C, three oblong tufts 80 are disclosed. An oblong tuft is obtained by partially flattening a round tuft, such as tuft 78, prior to heat fusing portion 46, and then causing portion 46 to be heat-fused together. Figs. 9A-C are similar to Figs 8A-C except that Fig. 9A discloses a double layer tuft 82. Tuft 82 has a shorter layer of bristles 84 behind which are a relatively longer layer of bristles 86. Although the two layers have similar contours, this is not required. The resulting tufts 88 and 90 have two independent topographies which are interpenetrating within each other. Referring to Fig. 9D, the right tuft of three tufts 88 is shown anchored to a toothbrush head 92 of a toothbrush 94. Only one tuft 88 is shown secured to head 92 for simplicity, but an actual toothbrush would typically have a large number of tufts secured to the head. Toothbrush 94 can be made by the following process which is generally understood by those skilled in the art and which is disclosed in U.S. Patent No. 5,609,890 which issued on March 11, 1997. Tuft 88 along with other tufts of a similar nature are inserted into respective apertures in a metal insert bar. The insert bar is then secured to a first mold half of an injection molding machine such that fused ends 46 project into the mold cavity. The mold is then closed to secure the first mold half to a second mold half. Fused ends 46 of the tufts are located just within the mold cavity with the non- fused portions of the bristles being located outside of the mold cavity. Polypropylene is then injected into the mold cavity to form a handle 96 with integral head 92. The polypropylene is then cooled at which point the toothbrush is removed from the mold. The cooled, hardened polypropylene secures fused ends 46 of the tufts to head 92 of toothbrush 94. Optionally, the toothbrush can be moved to a second injection molding station to apply a rubber to portions of handle 96. A thermoplastic elastomer (rubber) is injected into the second mold after which the elastomer is cooled and the finished toothbrush is removed from the mold. The toothbrush is then packaged. Figs. 10 A-E disclose toothbrush heads and portions of integral handles with tufts secured to the heads. These tufts have not been rolled up, as described above, and thus have a very small width "A" when compared to their length "B". A ratio of width "A" to length "B" is preferably about 0.25 or less. Length "B" can be a straight line length, a curvilinear length (see Fig. 10(E) or a distance along the longest dimension of the tuft in which this tuft is bent to form two or more tuft sections which are at angles greater than zero to each other. These toothbrushes can be made by the process described above. All of these tufts can have from only one up to a very large number of layers of bristles in each tuft. In this case, the tuft's width/length ratio may be greater than .25. Fig. 10A is a side view of one embodiment of a toothbrush while Fig. 10B is a top view of the same embodiment. Toothbrush 98 includes a handle 100 and a head 102. Tufts 104, as shown in Fig 10A, alternate from a relatively taller tuft to a relatively shorter tuft. Fig. 10B shows that the tufts are all straight, and that they are all the same length except for the shorter tuft which is furthest from handle 100. The bristles in each tuft are preferably parallel to each other. Fig. 10C discloses a toothbrush 106 with a different tuft pattern. Here, four long straight rows of tufts 108 are oriented parallel to a long axis 109 of head 102. Two end tufts 110 are located at either end of head 102 and are curved in shape. In Fig. 10D, a series of identical, straight tufts are oriented on head 102 at an oblique angle to axis 109. Fig. 10E discloses identical curved tufts 114 which arc across the width of head 102. Turning to Fig. 11, another embodiment of an apparatus for making tufts is disclosed. A large number of filaments F01, F02...F50 are passed through a feeding rack 120. Rack 120 brings the filaments into close proximity yet keeps them from crossing over by maintaining a preset gap between each of the filaments. This is accomplished by having separate apertures through rack 120 for each filament. The filaments then pass through a plastic welding means such as a heating element 122 which includes a scanning laser for periodically fusing (securing) the filaments together at, for example, location 124. Alternatively, an ultra-sonic or hot air system can be used to fuse the bristles together. A drive system 126 includes four nip wheels which engage the filaments and are rotated to move the filaments through the apparatus. The nip wheels do not need to contact all of the filaments because the filaments are fused together at this point. A punch press then severs a section of the filaments 130 free from the filaments with a die 132 which reciprocates in the directions of an arrow 134. A cutter (not shown) then cuts sections 130 into individual tufts of bristles 136. Turning to Figs. 12A-B, two tufts are disclosed which result when heater 122 (Fig. 11) is rotated such that it fuses the filaments at an oblique angle to the direction of travel (long axis) of the filaments. In Fig. 11, the filaments are fused in a direction perpendicular to the long axis of the filaments. This results in tuft 138 (Fig. 12 A) in which bristles 140 are at an oblique angle to their fused portions 142. Tuft 144 (Fig 12B) is formed by placing two of tufts 138 together with one of tufts 138 having been flipped over. The two portions 142 are then fused together. These two tufts add further variety to the types of tufts which can be incorporated into a toothbrush.

Claims: C L A I M S 1. A toothbrush, comprising: a handle; a head extending from the handle; and a tuft of bristles which are joined together at a base end of the bristles and secured to the head at the base end, the tuft having a width and a length, a ratio of the width to the length being about 0.25 or less. 2. The toothbrush of claim 1, wherein the bristles are substantially parallel to each other. 3. The toothbrush of claim 1, wherein the tuft is only a single layer of bristles wide. 4. The toothbrush of claim 1 , wherein the tuft is more than one layer of bristles wide. 5. The toothbrush of claim 1, wherein the bristles are joined together at their base ends by one of (a) heat- fusion, (b) an adhesive, and (c) a synthetic and/or natural resin. 6. The toothbrush of claim 1, wherein one of the bristles has a characteristic that is different from that characteristic of another one of the bristles, the characteristic being selected from the group consisting of length, material, color, gray scale, surface characteristic and cross-sectional shape. 7. A toothbrush, comprising: a handle; a head extending from the handle; and a tuft of bristles which are joined together at a base end of the bristles and secured to the head at the base end, wherein one of the bristles has a characteristic that is different from that characteristic of another one of the bristles, the characteristic being selected from the group consisting of material, color, gray scale, surface characteristic and cross-sectional shape. 8. The toothbrush of claim 7, wherein the tuft has a width and a length, a ratio of the width to the length being about 0.25 or less. 9. The toothbrush of claim 7, wherein the bristles are substantially parallel to each other. 10. The toothbrush of claim 7, wherein the tuft is only a single layer of bristles wide. 11. The toothbrush of claim 7, wherein the tuft is more than one layer of bristles wide. 12. The toothbrush of claim 7, wherein the bristles are joined together at one of their ends by one of (a) heat-fusion, (b) an adhesive, and (c) a synthetic and/or natural resin. 13. A toothbrush, comprising: a handle; a head extending from the handle; and a tuft of bristles which are joined together at a base end of the bristles and secured to the head at the base end, a first one of the bristles being located in the tuft in a predetermined position and/or orientation relative to a second one of the bristles. 14. The toothbrush of claim 13, wherein every bristle in the tuft is located in the tuft in a predetermined position and/or orientation relative to the other bristles in the tuft. 15. The toothbrush of claim 13, wherein the tuft has a width and a length, a ratio of the width to the length being about 0.25 or less. 16. The toothbrush of claim 13, wherein one of the bristles has a characteristic that is different from that characteristic of another one of the bristles, the characteristic being selected from the group consisting of length, material, color, gray scale, surface characteristic and cross-sectional shape. 17. The toothbrush of claim 13, wherein the bristles are joined together at one of their ends by one of (a) heat-fusion, (b) an adhesive, and (c) a synthetic and/or natural resin. 18. A method of making a tuft of bristles for use in a toothbrush, comprising the steps of: positioning a group of individual bristles adjacent to each other such that the bristles are substantially parallel to each other in their longest dimension; securing one portion of each bristle to one portion of at least one other bristle to form a bristle ribbon; and, severing at least one of the secured portions between bristles to cut free a tuft of bristles from the bristle ribbon. 19. The method of claim 18, wherein the securing step is accomplished by heating the portions of the bristles to sufficiently soften the portions of the bristles to fuse the portions together. 20. The method of claim 18, further comprising the step of: cutting off a portion of one end of at least one of the bristles to alter the length of the one or more cut bristles. 21. The method of claim 18, further comprising the steps of: heating an end of each of the bristles; pulling the heated bristle ends away from the bristles to cause the heated bristle ends to neck down; and cooling the heated bristle ends to below their melting temperature. 22. The method of claim 21, further comprising the step of: between the pulling and cooling steps, bending the heated bristle ends. 23. The method of claim 18, further comprising the steps of: securing another portion of each bristle to another portion of at least one other bristle; folding the bristles between the one portions and the other portions such that the one portions and the other portions are adjacent to each other; and securing the one portions to the other portions. 24. The method of claim 23, further comprising the steps of: heating the portions of the bristles where they were folded; and pressing the heated portions towards each other. 25. The method of claim 18, wherein the positioning step includes the steps of: providing a supply of bristles; and successively picking single bristles from the supply of bristles. 26. The method of claim 18, wherein the positioning step includes the step of: placing a first one of the bristles in a predetermined location relative to a second one of the bristles. 27. The method of claim 18, wherein the positioning step is effective to place the group of individual bristles in a predetermined pattern. 28. The method of claim 18, wherein following the securing step, the shape of the tuft is altered such that the position and/or orientation of a first one of the bristles is changed relative to a second one of the bristles. 29. The method of claim 28, wherein following altering of the tuft shape one end of the bristles are secured together by heat fusion. 30. A method of processing bristles which is useful in forming a tuft of bristles, comprising the steps of: providing a supply of bristles; and, successively removing single bristles from the supply. 31. The method of claim 30, further comprising the step of: aligning the removed bristles in a single layer such that the removed bristles are essentially parallel to each other. 32. The method of claim 31, further comprising the step of: moving one or more of the removed bristles along a long axis of the one or more removed bristles to provide a contour to the removed bristles. 33. The method of claim 32, further comprising the step of: cutting away a section of one end of each of the removed bristles. 34. The method of claim 31, further comprising the step of: securing together a portion of each one of the removed bristles to a portion of at least one of the other removed bristles to form a bristle ribbon. 35. The method of claim 34, further comprising the step of: severing at least one of the secured bristle portions to free a tuft of bristles from the bristle ribbon. 36. The method of claim 35, further comprising the step of: joining together two or more tufts of bristles which have been severed from the bristle ribbon. 37. The method of claim 31, further comprising the step of: creating one or more additional bristle ribbons independent from each other and the bristle ribbon; and joining together the one or more additional bristle ribbons and the bristle ribbon. 38. The method of claim 37, further comprising the step of: severing a section of the joined together bristle ribbons free from the joined together bristle ribbons to create a tuft of bristles. 39. The method of claim 30, further comprising the step of: providing one or more additional supplies of bristles, the bristles of the one or more additional supplies differing among each additional supply and from the bristles of the first supply in length, material, color, gray scale, surface characteristic and/or cross-sectional shape, wherein the aligning step is effective to combine together the bristles of the first supply and the one or more additional supplies in the single layer. 40. The method of claim 39, wherein the aligning step is effective to combine together the bristles of the first supply and the one or more additional supplies in a predetermined order. 41. The method of claim 18, wherein the tuft of bristles has a width and a length, a ratio of the width to the length being about 0.25 or less. 42. A method of making a tuft of bristles for use in a toothbrush, comprising the steps of: (i) supplying a multiplicity of filaments; (ii) positioning the filaments such that each filament is adjacent at least one other filament and essentially parallel with at least one other filament; (iii) securing together a portion of each filament to a portion of at least one other filament; (iv) severing all of the filaments to free a section of the filaments from the filaments, the filament section including the secured together portions of the filaments; and, (v) cutting one or more of the secured together portions of the filament section to separate the filament section into one or more tufts of bristles. 43. The method of claim 42, further comprising the step of: repeating steps (iii) - (v) a multiplicity of times to produce a multiplicity if tufts of bristles. 44. The method of claim 42, wherein the securing step secures the portions of the filaments together in a direction which is essentially perpendicular to a long axis of the filaments. 45. The method of claim 42, wherein the securing step secures the portions of the filaments together in a direction which is at an oblique angle to a long axis of the filaments.

Inventors: BEALS DONNA, CASTILLO BRADLEY, CHIANG CASPER WEN-TIEN, FENG YAN, ROBERTS MICHAEL, ZAPANTA EDGARDO GOTANGCO, BEALS, DONNA, CASTILLO, BRADLEY, CHIANG, CASPER, WEN-TIEN, FENG, YAN, ROBERTS, MICHAEL, ZAPANTA, EDGARDO, GOTANGCO
Applicants: GILLETTE CANADA, GILLETTE CANADA INC.
Application year: 1999
Main classification: A46D1
IPC codes: A46B3, A46D1