Oral care implement
10278484 ยท 2019-05-07
Assignee
Inventors
Cpc classification
A46D3/005
HUMAN NECESSITIES
A46B2200/1066
HUMAN NECESSITIES
International classification
Abstract
An oral care implement is provided. The oral care implement may include a handle comprising a core and a cover enveloping the core. The cover may be formed from a substantially translucent first rigid material. The core may be formed from a second rigid material and a plurality of elements, the plurality of elements suspended within the second rigid material and visible through the cover. In other embodiments the core may include a foamed material.
Claims
1. An oral care implement, comprising: a handle having a core and a cover surrounding an entirety of the core so that no portion of the core is exposed; and a head comprising at least one cleaning element, the head being connected to the handle; and wherein the head and the cover of the handle are integrally formed as a unitary part; wherein a first portion of the cover is made from a first material and a second portion of the cover is made from a second material; wherein the first material is a hard material and the second material is an elastic material; and wherein the cover comprises a plurality of the second portions spaced apart from one another along the handle.
2. The oral care implement of claim 1, wherein the core comprises a foamed material.
3. The oral care implement of claim 1, wherein the cover is at least partially transparent.
4. The oral care implement of claim 1, wherein the cover is overmolded onto the core.
5. The oral care implement of claim 1, wherein the handle comprises one or more sections that are overmolded onto the cover and out of contact with the core.
6. The oral care implement of claim 1, wherein the head comprises at least one tooth cleaning element and the oral care implement comprises a toothbrush.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
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DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
(10) The following description of the preferred embodiments is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.
(11) The description of illustrative embodiments according to principles of the present invention is intended to be read in connection with the accompanying drawings, which are to be considered part of the entire written description. In the description of embodiments of the invention disclosed herein, any reference to direction or orientation is merely intended for convenience of description and is not intended in any way to limit the scope of the present invention. Relative terms such as lower, upper, horizontal, vertical, above, below, up, down, top and bottom as well as derivative thereof (e.g., horizontally, downwardly, upwardly, etc.) should be construed to refer to the orientation as then described or as shown in the drawing under discussion. These relative terms are for convenience of description only and do not require that the apparatus be constructed or operated in a particular orientation unless explicitly indicated as such. Terms such as attached, affixed, connected, coupled, interconnected, and similar refer to a relationship wherein structures are secured or attached to one another either directly or indirectly through intervening structures, as well as both movable or rigid attachments or relationships, unless expressly described otherwise. Moreover, the features and benefits of the invention are illustrated by reference to the preferred embodiments. Accordingly, the invention expressly should not be limited to such preferred embodiments illustrating some possible non-limiting combination of features that may exist alone or in other combinations of features.
(12) In the following description, the invention is discussed in terms of a toothbrush, but could be in the form of another oral care implement or ansate implement, such as a soft tissue cleaner. The oral care implement is preferably self-contained, portable and hand-held. Further, it is understood that other embodiments may be utilized and structural and functional modifications may be made without departing from the scope of the present invention.
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(14) The head 120 carries one or more cleaning elements 130. The cleaning elements 130 extend beyond a front face 122 of the head 120. In this embodiment, the cleaning elements 130 comprise tooth cleaning elements but, in a variation to this embodiment, they may instead or additionally comprise soft tissue cleaning elements. The tooth cleaning elements 130 may be connected to the head 120 by any suitable conventional attachment method used in the art including, without limitation, anchor free tufting (AFT), in mold tufting (IFT), stapling and anchoring. The tooth cleaning elements 130 may include a variety of bristle and/or flexible elastomeric cleaning and/or polishing elements. It should be noted that the cleaning elements 130 in the drawings are illustrated substantially in block without the individual bristle strands being detailed, for convenience and clarity.
(15) Any provided bristles are preferably made from nylon, although other materials could be used. The bristles also preferably have a generally circular cross-sectional shape, but could have other cross-sectional shapes. The diameter of the bristles can vary depending on the desired cleaning action of the bristles. Any provided soft tissue cleaning element(s) are preferably made from an elastomer, such as a thermoplastic elastomer (TPE), or rubber. The soft tissue cleaning element(s) may comprise one or more tissue engaging elements, such as elongated cleaning elements, which may be linear or nonlinear, and/or one or more nubs.
(16) As used herein, a nub is generally meant to include a column-like protrusion (without limitation to the cross-sectional shape of the protrusion) which is upstanding from a base surface. In a general sense, the nub, in the preferred construction, has a height that is greater than the width at the base of the nub (as measured in the longest direction). Nevertheless, nubs could include projections wherein the widths and heights are roughly the same or wherein the heights are somewhat smaller than the base widths. Moreover, in some circumstances (e.g., where the nub tapers to a tip or includes a base portion that narrows to a smaller projection), the base width can be substantially larger than the height.
(17) The cleaning elements 130 carried by the head 120 may be arranged in any suitable pattern and the invention is not limited by any particular arrangement, shape, type, and/or number of cleaning element(s) 130 provided.
(18) In some embodiments, any one or more of the front face 122 itself, a back face 124 opposite to the front face 122, and the two opposing lateral sides 126, 128 of the head 120 may include an elastomeric tongue cleaner and/or other tooth or soft tissue cleaning elements (not shown), of any of the forms discussed above. The head 120 in this embodiment has an elongated elliptical or oval shape in top view; however, in other embodiments the head 120 may be round or substantially rectangular in top view.
(19) The handle 110 is a member that is dimensioned so that a user can readily grip and manipulate the implement 1. The handle 110 may have any suitable ergonomic and aesthetically pleasing configuration dimensioned to be gripped by a user, and is not limited to the appearance illustrated in the enclosed drawings.
(20) The handle 110 comprises an outer cover, shell or housing 112 and a core 118 that is enveloped by the cover 112. That is, the cover 112 completely covers or surrounds the core 118, such that no part of the core 118 is exposed to the exterior of the implement 1. The cover 112 is in contact with a surface 119 of the core 118. The cover 112 is free of post-consumer recycled material and, preferably, is made of virgin food-grade plastic. In a variation to this embodiment, the cover 112 may comprise pre-consumer recycled material, optionally in an amount up to 30% wt of the cover 112. More specifically, a first portion 114 of the cover 112 is made from a hard bio-sourced cellulose polymer such as cellulose acetate propionate (CAP) or cellulose acetate butyrate (CAB). The first portion 114 of the cover 112 is transparent, such that the core 118 is visible through the first portion 114 of the cover 112 from the exterior of the implement 1. In variations to this embodiment, the first portion 114 of the cover 112 may instead be wholly, or in part, translucent or opaque. In a further variation to this embodiment, the first portion 114 is made from polypropylene (PP) or a still different material.
(21) A second portion 116 of the cover 112 is made from an opaque and elastic material, in this case a thermoplastic elastomer (TPE). The second portion 116 is located at that part of the handle 110 where a user's thumb would rest during normal use of the implement 1, and acts as a resilient grip.
(22) The first portion 114 of the cover 112 is in contact with a first part of the core 118 and the second portion 116 of the cover 112 is in contact with a second part of the core 118. That is, each of the first and second portions 114, 116 is in contact with the surface 119 of the core 118. Accordingly, each of the first and second portions 114, 116 is considered to be comprised in the cover 112.
(23) In a variation to the illustrated first embodiment, the handle 110 has a plurality of second portions 116, rather than only one second portion 116. Such an implement 1 according to a second embodiment of the present invention is shown in
(24) The plurality of second portions 116 are spaced apart from one another on a surface of the implement 1 at locations along the longitudinal axis of the handle 110 and/or around the handle 110. The plurality of second portions 116 are all made of TPE. There is thus provided a plurality of resilient grips for contacting a user's hand during normal use of the implement 1. In a variation to this embodiment, the second portions 116 may be made of different materials. One, or more than one, of the plurality of spaced apart second portions 116 may be made from an elastic material, such as TPE. Alternatively or additionally, one or more than one, or all, of the plurality of spaced apart second portions 116 may be made of a rigid material, such as PP, CAP or CAB. When visually distinct from the first portion 114 of the handle 110, e.g. when the first portion 114 has a different colour to one or all of the second portions 116, regardless as to whether the portion(s) 114, 116 are of the same material, the plurality of spaced apart second portions 116 may provide the handle 110 with an appealing appearance.
(25) Each of the second portions 116 of the cover 112 is in contact with a respective second part of the core 118. Indeed, each of the first and second portions 114, 116 is in contact with the surface 119 of the core 118. Accordingly, each of the first and second portions 114, 116 is considered to be comprised in the cover 112.
(26) In the implement 1 of the second embodiment shown in
(27) A third embodiment of an implement 1 according to the present invention is shown in
(28) In the third embodiment, the core 118 extends from the handle 110 into the neck 140. Indeed, the core 118 extends from the handle 110 into both the neck 140 and the head 120. Accordingly, a greater proportion of the oral care implement 1 may be made of recycled material, such as post-consumer recycled material, yet the implement 1 may be provided with a smooth, comfortable surface, a part of which will be held by a user and a part of which will contact tissue inside the user's mouth, during use of the implement 1. The whole of the core 118 is still enveloped by the cover 112 in a similar manner to that of the first and second embodiments. Accordingly, in the third embodiment, the recycled material core 118 still is not exposed at an outer surface of the implement 1.
(29) In variations to the illustrated first, second and third embodiments, the cover 112 of the handle 110 may have a plurality of first portions 114, rather than only one first portion 114 as shown in
(30) The handle 110 of the fourth embodiment of an oral care implement 1 comprises a core 118 and a cover 112 enveloping the core 118, but excludes any part equivalent to the section 117 shown in
(31) In each of the first, second and fourth embodiments, the neck 140 and the head 120 of the implement 1 are formed by the cover 112. That is, the head 120, the neck 140, and the cover 112 of the handle 110 are all integrally formed as one unitary molded part. In the third embodiment, the neck 140 and the head 120 of the implement 1 are partially formed by the cover 112. That is, the cover 112 of the handle 110, and the outer parts of the head 120 and neck 140 are all integrally formed as one unitary molded part. In each of the embodiments, none of the core 118 is exposed at an outer surface of the implement 1.
(32) In each of the first to fourth embodiments, the cover 112 is overmolded onto the surface 119 of the core 118. Preferably this is achieved using one of the methods of manufacture discussed below. However, in respective variations to these four embodiments, the cover 112, or only some of the portions 114, 116 thereof, may instead be disposed on the surface 119 of the core 118 by some other method. For example, the cover 112, or only some of the portions 114, 116 thereof, may instead be adhered to the surface 119 of the core 118, or coated onto the surface 119 of the core 118 as a coating or a film.
(33) In each of the first to fourth embodiments, the core 118 comprises foamed, post-consumer recycled polypropylene (PP), as illustrated by way of example in
(34) In the first to third embodiments, the respective first portions 114 of the cover 112 are of a transparent material, and the respective cores 118 include a colorant that has been added to the recycled material so as to enhance the visibility of the core 118 through the cover 112. However, in variations to these embodiments, the core 118 may exclude a colorant (or at least a colorant that has been added to the recycled material during the manufacture of the implement 1 from the recycled material), particularly in cases when the whole of the cover 112 is opaque.
(35) In each of the first to fourth embodiments, the core 118 may consist of about 95% by weight recycled material. However, in respective variations to these embodiments, the core 118 may consist of more or less than this percentage by weight recycled material. For example, in some embodiments, the core comprises only at least 50% by weight recycled material. In other embodiments, the core 118 comprises at least 75% by weight recycled material. In preferred embodiments, the core 118 comprises at least 90% by weight recycled material, more preferably at least 95% by weight recycled material, and most preferably at least 99% by weight recycled material. The core 118 may be free of foaming agent and/or colourant. Naturally, the more recycled material provided in the core 118, the less virgin material is used in the manufacture of the implement 1.
(36) In each of the first, second and fourth embodiments, the core 118 makes up approximately 20 to 25% of the volume of the implement 1 and approximately 30 to 40% of the volume of the handle 110. In the third embodiment, the core 118 makes up approximately 30 to 40% of the volume of the implement 1 and approximately 30 to 40% of the volume of the handle 110. In variations to these embodiments, the cover 112 may be thinner than that shown in
(37) In the four embodiments discussed in detail herein, the head 120 is irremovably connected to the handle 110 via the neck 140. In respective variations to the first, second and fourth embodiments, the head 120 may be detachably connectable to the handle 110 to enable substitution of the head 120 when the cleaning elements 130 have become worn, without needing to dispose of the whole implement 1. In such variations, either the neck 140 is removable from the handle 110 with the head 120, or the neck 140 is removable from the head 120 with the handle 110.
(38) In respective variations to the above described first to fourth embodiments, the first and section portions 114, 116 of the cover 112 may be made of the same material, such as PP, optionally with the first portion 114 coloured a different colour to the second portion(s) 116.
(39) In variations to the illustrated second and third embodiments, two or more of the second portions 116 that are spaced from one another on the surface of the implements 1 may be in direct communication with each other underneath the surface of the implements 1. For example, a hole (not shown) may be provided through the core 118 and/or through the first part 114, within which hole material forming two or more of the second portions 116 is located. The hole would preferably be circumferentially complete. Accordingly, during manufacture of the implement 1, it may be possible to form the second sections 116 that contact each other using a single shot of injected material.
(40) A first method for forming an oral care implement in accordance with the present invention will now be described. The implement 1 of the second embodiment shown in
(41) As a first step, one or more post-consumer plastic structures, such as bottles, cartons, packaging or other disposable goods (such as pre-used oral care implements), made of a thermoplastic, such as polypropylene are processed by methods known in the art to create a material comprising, and preferably consisting at least substantially entirely of, recycled thermoplastic.
(42) The recycled thermoplastic is then melted and injected into the cavity of a mold, in order to form the core 118 by injection molding. Any method for forming the core 118 by injection molding may be utilised. However, a specific example is given below for completeness.
(43) The recycled material, possibly in the form of pellets, is introduced to a hopper or cylinder of an injection molding machine, in which hopper the material is plasticised and mixed, through a combination of mechanical and thermal treatment. A colourant, possibly in the form of pellets, may be added to the recycled material in the hopper to be plasticized and melted together, in order to provide the resultant core 118 with a coloured appearance. A foaming agent also may be added into the hopper to cause subsequent foaming of the material. Alternatively, the colourant and/or the foaming agent can be added to the recycled material after it is plasticized and melted.
(44) The recycled material is fed as core material in a flowable state from the hopper, through a supply conduit into a first cavity of a mold, which first cavity is formed by walls of respective mold halves of the mold. The first cavity has a shape corresponding to the desired shape of the core.
(45) The mold is cooled to cause the core material to harden. Moreover, as the material includes the foaming agent, the material foams within the first cavity. Pressure in the first cavity may be reduced, so as to encourage foaming of the material. Once the hard core 118 has been formed, the mold halves are separated from each another and the core 118 is ejected or otherwise removed from the first cavity of the mold.
(46) Although in this example the core 118 is formed by injection molding, the core may in other embodiments be created by any other method involving forming core material comprising or consisting of recycled material into a shape, such as cutting the core 118 from a larger piece of material, or extruding the core material (comprising or consisting of recycled material) to form the core 118. In cases when the core 118 is formed by extrusion, the core 118 may be formed with at least one hollow part such that at least a part of the core 118 is formed as a tube, in order to reduce the amount of material required to form the core 118 and the implement 1 overall. In one example extrusion process, the core material (comprising or consisting of recycled material) may be extruded from an annular die and then cut to length while still soft, resulting in a pinched-shut cut at each end of the core 118, which thus seals ends of the core to create an air bubble in the core 118. In another example extrusion process, the core material (comprising or consisting of recycled material) may be extruded from an annular die and then cut to length after the core material 118 has been allowed to completely or partially harden, resulting in a core 118 having a tubular form. In further variations to the method, the core 118 may be provided as a pre-formed shape of core material (comprising or consisting of recycled material).
(47) Once provided, the hard core 118 is then placed in a second cavity (in either the first mold or a second mold) which has a first volume corresponding to the shape of the head 120 and neck 140 of the implement 1 to be formed, and a second volume corresponding to the shape of the first portion 114 of the cover 112 of the handle 110. The first and second volumes are parts of the same, second cavity and thus are in fluid communication with each other. The first volume has a shape suitable to cause tuft holes to be formed in the head 120, in which holes tooth cleaning elements 130 can later be disposed using staples. The second volume has a volume greater than that of the first cavity, to allow first cover material that will form the first portion 114 of the cover 112 to flow around the core 118 and contact a first part of the surface 119 of the core 118. The core 118 is spaced from walls of the second cavity by one or more spacers, such as shut-offs, which contact second parts of the surface 119 of the core 118. Accordingly, the second parts of the surface 119 are concealed from the second cavity whereas the first part of the surface 119 of the core 118 is exposed to the second cavity.
(48) Thereafter, the first cover material, which in this example is free of post-consumer recycled material (optionally is virgin food-grade plastic) and comprises cellulose polymer, is introduced to the second cavity in a flowable state. In a variation to this embodiment, the first cover material may comprise pre-consumer recycled material. Sufficient first cover material is provided to fully form the first portion 114 of the cover 112. The first cover material covers the first part of the surface 119 of the core 118 while the second parts of the surface 119 are concealed. The first cover material is thereafter allowed to harden. Accordingly, the first portion 114 of the cover 112 is overmolded onto the core 118.
(49) Next, mold halves of the second mold are separated from each another and the combination of the head 120, neck 140, first portion 114 and core 118 is ejected or otherwise removed from the second cavity of the second mold.
(50) The combination is then placed in a third cavity (in either the first mold or another mold) which third cavity has a first volume corresponding to the shape of the head 120 and neck 140, and a second volume corresponding to the shape of the full handle 110. The first and second volumes are parts of the same, third cavity and thus are in fluid communication with each other. The first volume has a volume identical in shape and size to that of the second cavity. On the other hand, the second volume has a volume greater than that of the second cavity, to allow second cover material that will form the second portions 116 of the cover 112 and the section 117 to flow around the combination and contact the second parts of the surface 119 of the core 118. Accordingly, the second parts of the surface 119 are exposed to the third cavity.
(51) Thereafter, the second cover material, which in this example comprises a thermoplastic elastomer (TPE), is introduced to the third cavity in a flowable state. Sufficient second cover material is provided to fully form the second portions 116 of the cover 112 and to form the section 117. The second cover material covers the second parts of the surface 119 of the core 118 while the first part of the surface 119 is concealed by the first portion 114. The second cover material is thereafter allowed to set.
(52) Accordingly, the second portions 116 of the cover 112, and indeed the whole cover 112, is overmolded onto the core 118. That is, the core 118 is enveloped by cover material, which cover material comprises the first cover material and the second cover material.
(53) Next, mold halves that form the third cavity are separated from each another and the body 100 of the implement 1 is ejected or otherwise removed from the third cavity.
(54) Finally, the body 100 is subjected to a process for disposing tooth cleaning elements 130 in the tuft holes formed in the head 120, to obtain a finished implement 1. In this embodiment the process involves attaching bundles of bristles 130 in the holes using staples, according to a method that may be known in the art.
(55) A second method for forming an oral care implement in accordance with the present invention will now be described. The implement 1 of the first embodiment shown in
(56) The second method is substantially the same as the described first method. However, in the second method, once provided, and when in the second cavity, the hard core 118 is spaced from walls of the second cavity by only one spacer, such as a shut-off, which contacts a single second part of the surface 119 of the core 118. Thereafter, the first cover material is introduced to the second cavity in a flowable state and covers the first part of the surface 119 of the core 118 while the second part of the surface 119 is concealed, and is then allowed to harden.
(57) Mold halves forming the second cavity are separated from each another and the combination of the head 120, neck 140, first portion 114 and core 118 is ejected or otherwise removed from the second cavity.
(58) When the combination is subsequently placed in the third cavity, the second volume of the third cavity has a volume greater than that of the second cavity, to allow the second cover material that will form the single second portion 116 of the cover 112 to flow around the combination and contact the single second part of the surface 119 of the core 118. Accordingly, the single second part of the surface 119 is exposed to the third cavity. When the second cover material is introduced to the third cavity in a flowable state, only sufficient second cover material to fully form the single second portion 116 of the cover 112 need be provided. The second cover material covers the single second part of the surface 119 of the core 118 while the first part of the surface 119 is concealed by the first portion 114. The second cover material is thereafter allowed to set. Accordingly, the second portion 116 of the cover 112, and indeed the whole cover 112, is overmolded onto the core 118 so that the cover 112 envelops the core 118.
(59) Finally, the body 100 is subjected to a process for disposing tooth cleaning elements 130 in the tuft holes formed in the head 120, to obtain a finished implement 1.
(60) In variations to the first and second methods of the present invention, the first and second cover materials may be the same material, e.g. cellulose polymer or polypropylene (PP) or a thermoplastic elastomer (TPE).
(61) In a third method for forming an oral care implement in accordance with the present invention, the core 118 is dimensioned such that it will ultimately form part of the neck 140, and optionally also part of the head 120, of the implement 1. Accordingly, the implement 1 of the third embodiment shown in
(62) In the third method, the core 118 may be provided in a manner substantially as in any of the embodiments described above, except that the core 118 has a greater longitudinal length. For example, the core may be formed in a first cavity of a mold by injection molding, substantially as described above.
(63) Once provided, the hard core 118 is placed in a second cavity of either the first mold or another mold, substantially as described above for the first or second method, except that the core is spaced from walls of the second cavity in both the first volume and the second volume of the second cavity. The first volume corresponds to the shape of the head 120 and neck 140 of the implement 1 to be formed, the second volume corresponds to the shape of the first portion 114 of the cover 112 of the handle 110 of the implement 1 to be formed, and the first and second volumes are parts of the same, second cavity and thus are in fluid communication with each other. The second cavity has a volume greater than that of the first cavity, to allow the first cover material that will form the first portion 114 of the cover 112 to flow around the core 118 and contact a first part of the surface 119 of the core 118. The core 118 is again spaced from walls of the second cavity by a spacer, such as a shut-off, which contacts a second part of the surface 119 of the core 118. However, due to the increased longitudinal length of the core 118, the core is locally spaced from the walls of the second cavity in both the first and second volumes of the second cavity. Accordingly, the second part of the surface 119 is concealed from the second cavity whereas the first part of the surface 119 of the core 118 is exposed to the second cavity.
(64) Thereafter, the first cover material is introduced to the second cavity in a flowable state substantially as described above for the first or second method. Sufficient first cover material is provided to fully form the first portion 114 of the cover 112. The first cover material covers the first part of the surface 119 of the core 118 while the second part of the surface 119 is concealed. The first cover material is thereafter allowed to harden. Accordingly, the first portion 114 of the cover 112 is overmolded onto the core 118.
(65) Next, mold halves that form the second cavity are separated from each another and the combination of the head 120, neck 140, first portion 114 and core 118 is ejected or otherwise removed from the second cavity. The combination is then placed in a third cavity of either the same mold or of another mold for the creation of the single second portion 116 using second cover material, as discussed above for the second method, such that the cover 112 envelops the core 118.
(66) In respective variations to the above-described first, second and third methods, one or more of the one or more spacers (which may be positioning pins) used in the second cavity are withdrawn from the surface 119 of the core 118 during or after the introduction of the first cover material into the second cavity (but, in any event, while at least a portion of the first cover material is flowable), such that the first cover material fills voids left behind by the removal of the spacer(s) without disturbing the position of the core 118 relative to the walls of the second cavity. Accordingly, the first cover material covers the first part of the surface 119 of the core 118 while the second parts of the surface 119 are concealed, then the first cover material covers one or more of the second parts of the surface 119 after the spacer(s) are withdrawn or removed. The first cover material is thereafter allowed to harden, and the combination is ejected from the second cavity and placed in the third cavity, as discussed above for either of the first and second methods.
(67) A fourth method for forming an oral care implement in accordance with the present invention will now be described. The implement 1 of the fourth embodiment shown in
(68) In the fourth method, the core 118 of the implement is provided. The core 118 may be formed, either by the relevant part of the first, second or third methods described above, or by any other method.
(69) The hard core 118 is then placed in a second cavity, of either the first mold or of a second mold, which second cavity has a first volume corresponding to the shape of the head 120 and neck 140 of the implement 1 to be formed, and a second volume corresponding to the shape of the final handle 110 to be formed. The first and second volumes are parts of the same, second cavity and thus are in fluid communication with each other. The first volume again has a shape suitable to cause tuft holes to be formed in the head 120. The second volume has a volume configured to allow cover material that will form the cover 112 to flow around the core 118 and contact a first part of the surface 119 of the core 118. The core 118 is spaced from walls of the second cavity by one or more spacers, such as positioning pins, which contact respective second part(s) of the surface 119 of the core 118. Accordingly, the second part(s) of the surface 119 are concealed from the second cavity whereas the first part of the surface 119 of the core 118 is exposed to the second cavity.
(70) Thereafter, the cover material, which in this example is virgin food-grade CAP and/or polypropylene, is introduced to the second cavity in a flowable state. The cover material covers the first part of the surface 119 of the core 118 while the second part(s) of the surface 119 are concealed by the spacer(s).
(71) The one or more spacers is/are then withdrawn from the surface 119 of the core 118 during or after the introduction of the cover material into the second cavity (but, in any event, while at least a portion of the cover material is flowable), such that the cover material fills voids left behind by the removal of the spacer(s) without disturbing the position of the core 118 relative to the walls of the cavity. Accordingly, the cover material covers the first part of the surface 119 of the core 118 while the second part(s) of the surface 119 are concealed, and then covers the second part(s) of the surface 119 after the spacer(s) are withdrawn or removed. Ultimately, the cover material covers all of the surface 199, envelops the core 118 and also forms the outer surface of the implement 1. The cover material is thereafter allowed to harden. Accordingly, the whole cover 112 is overmolded onto the core 118 so as to envelop the core 118.
(72) Next, mold halves forming the second cavity are separated from each another and the body 100 comprising the head 120, neck 140 and handle 110 is ejected or otherwise removed from the second cavity of the second mold.
(73) Finally, the body 100 is subjected to a process for disposing tooth cleaning elements 130 in the tuft holes formed in the head 120, to obtain a finished implement 1.
(74) A fifth method for forming an oral care implement in accordance with the present invention will now be described. The implement 1 of the fourth embodiment shown in
(75) In the fifth method, rather than covering a hard core 118 with cover material, the method comprises enveloping core material (comprising recycled material) with cover material, while the core material is soft and/or in a flowable state. The fifth method comprises a dual injection process into a single cavity mold, in which core material comprising recycled material is injected into the cover material already disposed in a mold cavity, while at least a portion of the cover material is soft and/or in a flowable state.
(76) First, a cavity of a mold is provided, which cavity has a first volume corresponding to the shape of the head 120 and neck 140 of the implement 1 to be formed, and a second volume corresponding to the shape of the final handle 110 to be formed. Again, the first and second volumes are parts of the same cavity and thus are in fluid communication with each other.
(77) A mass of cover material, which in this example is virgin food-grade CAP and/or polypropylene, is introduced to the cavity in a flowable state before the core material (comprising recycled material) that will form the core 118 is introduced to the cavity. More particularly, a short shot of the cover material is injected into the cavity. In other words, the volume of the mass of cover material introduced to the cavity is smaller than the volume of the cavity itself, and smaller than the volume of the body 100 of the implement 1 to be manufactured. Outer parts of the mass of cover material, which contact the walls of the cavity, begin to harden, since the walls of the cavity are cooled.
(78) While an inner portion of the mass of cover material is still soft, a mass of core material, which comprises or consists of recycled polypropylene and/or other recycled material, and which will form the core 118 of the implement 1, is injected into the cavity and specifically into the inner portion of the mass of cover material. The cover and core materials are then allowed to harden. (If any of the core material remains exposed to the walls of the cavity, a small quantity of cover material subsequently may be injected into the cavity to fully isolate the core material from the walls of the cavity). As a result, the cover formed from the cover material envelops the core formed from the core material.
(79) Finally, the body 100 is subjected to a process for disposing tooth cleaning elements 130 in the tuft holes formed in the head 120, to obtain a finished implement 1.
(80) In respective variations to the above-described methods, in cases where the core 118 has one or more holes therethrough, the cover material (such as the second cover material) may be permitted to pass through the hole(s) during injection thereof, such as to more easily form plural second sections 116 of the cover 112 that are spaced apart from one another on a surface of the implement 1 being formed.
(81) In respective variations to the above-described methods, the structures that are recycled to create the pellets or flakes may be made of a plastic material other than polypropylene, or may comprise more than one type of plastic material. In still further variations, the structures may comprise or consist of non-plastic material.
(82) While in each of the above described methods the recycled material, which is comprised in or as core material, comprises recycled polypropylene, in variations to these methods the recycled material may additionally or alternatively comprise one or more post-consumer recycled plastic materials selected from the group comprising: polypropylene (PP), polystyrene (PS), low density or high density polyethylene (LDPE, HDPE), polyethylene terephthalate (PET), acrylonitrile butadiene styrene (ABS), cellulose propionate (CP), polyacrylate, polycarbonate, and styrene acrylonitrile (SAN). In further variations, in addition to one or more recycled plastic materials, in other embodiments, the core material may also comprise one or more further non-recycled (i.e. virgin) plastic materials, such as one or more materials selected from the above list. Alternatively or additionally, in addition to one or more recycled plastic materials, the core material may also comprise one or more further recycled or non-recycled non-plastic materials, such as a metal or an alloy, a ceramic, glass, a composite, or organic material such as wood dust, wood saw dust or wood chippings.
(83) In still further variations to the above-described methods, foaming agent and/or colourant may be omitted from the core material.
(84) While in each of the above described methods the cover material comprises polypropylene and/or cellulose acetate propionate, in variations to these methods the cover material may additionally or alternatively comprise one or more other materials, such as material selected from the group comprising: polypropylene (PP), polystyrene (PS), low density or high density polyethylene (LDPE, HDPE), polyethylene terephthalate (PET), acrylonitrile butadiene styrene (ABS), cellulose propionate (CP), polyacrylate, polycarbonate, and styrene acrylonitrile (SAN). In any event, it is preferable that the cover material is free of recycled material, or at least is free of post-consumer recycled material. In some embodiments, the cover material (such as one or both of the first and second cover materials discussed above) comprises pre-consumer recycled material.
(85) In respective variations to each of the above described methods in which the cover material forms a transparent cover or portion thereof, the cover material may instead form a translucent or an opaque cover or portion thereof.
(86) In still further variations to the above-described methods, the methods may comprise further step(s) in which additional components and/or materials are disposed on the outside of the cover out of contact with the core.
(87) In still further variations to the above-described methods, the disposition of cleaning element(s) 130 in the head 120 may not involve stapling. Other known methods for disposing tooth cleaning element(s) 130 in tuft holes after the completion of the injection molding process(es) may be used. Alternatively, the cleaning element(s) 130, such as tooth cleaning elements and/or tissue cleaning elements, may be formed of the cover material during the injection of the cover material into a mold cavity, in which case the cavity would not have a shape suitable to cause tuft holes to be formed in a head 120, but rather would have a shape suitable to cause the cleaning element(s) 130 to be formed integrally with the head 120 from the cover material. The disposition of cleaning element(s) 130 in the head 120 may be achieved during or after the formation of the head 120 by anchor free tufting or by any other method.
(88) In still further variations to the above-described methods, the head 120 and/or the neck 140 of the implement 1 may not be created from the cover material. That is, the head 120 and/or the neck 140 may not be integrally formed with the cover 112 of the implement 1 by the same formation process. In such cases, the head 120 and/or the neck 140 may be connected to the handle 110 in a subsequent process, such as by overmolding the material of the head 120 and/or the neck 140 onto the handle 110. Alternatively, the head 120, and optionally also the neck 140, may be formed as a component separate from the handle 110 but connectable to the handle 110. In such cases, the above-described respective cavities used to form the cover 112 would be suitably shaped to form the handle 110 without, or in isolation from, the head 120, and optionally also without, or in isolation from, the neck 140. That is, the cavities could exclude a volume corresponding to the shape of the head 120, and optionally also corresponding to the neck 140, of the implement 1 to be formed.