Patent Publication Number: US-2021186200-A1

Title: Oral Care Implement

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application is a continuation of U.S. patent application Ser. No. 15/525,726, filed May 10, 2017, which is a national stage entry under 35 U.S.C. § 371 of PCT/US2014/064719, filed Nov. 10, 2014, the entireties of which are incorporated herein by reference. 
    
    
     BACKGROUND 
     Oral care implements, such as toothbrushes, are required to be made with adequate strength to withstand many different types of users. In particular, some people are relatively hard on their oral care implements and may apply significant torque and pressure thereon during use, whereas other people may use a soft grip on the oral care implement during use. In addition, there is a continuing need to reduce the amount of plastic in mass manufactured products such as oral care implements. Therefore, a need exists for a hygienic oral care implement that has reduced materials while exhibiting the requisite strength not to break during use. 
     BRIEF SUMMARY 
     In aspects of this disclosure, a toothbrush handle includes a support structure formed of clarified polypropylene, the support structure comprising a web having a thickness in a first direction orthogonal to an axis of the toothbrush handle of less than 2 millimeters and at least one rib depending from the web and having a thickness in a second direction, angled relative to the first direction, of less than 2 millimeters and a body formed of thermoplastic elastomer disposed on the support structure to at least partially cover the web and the at least one rib, wherein the handle has a light transmissivity of greater than 40% through a portion of the handle at which the body covers at least a portion of the web and the at least one rib. 
     In one or more additional aspects, in a toothbrush handle as described in the preceding paragraph, the support structure further comprises a frame defining a void and the web extends across at least a portion of the void. 
     In one or more additional aspects, in a toothbrush handle as described in any of the preceding paragraphs, the at least one rib depends orthogonally from the web. 
     In one or more additional aspects, in a toothbrush handle as described in any of the preceding paragraphs, the web and the at least one rib extend along the axis from a position proximate an end of the handle toward a neck of the handle. 
     In one or more additional aspects, in a toothbrush handle as described in any of the preceding paragraphs, the light transmissivity is measured substantially along the first direction or the second direction. 
     In additional aspects of this disclosure, a toothbrush includes a handle and a head disposed at a distal end of the handle, wherein the handle comprises a plurality of support structures extending generally along a longitudinal axis of the handle from a position proximate a proximal end axially opposite the distal end toward the head, each of the support structures having a thickness of less than 2 millimeters in a direction orthogonal to the longitudinal axis. 
     In one or more additional aspects, in a toothbrush as described in the preceding paragraph, the plurality of support structures comprise a plurality of spaced-apart elongate ribs. 
     In one or more additional aspects, in a toothbrush as described in any of the preceding paragraphs, the support structures further comprise a web and the plurality of spaced-apart elongate ribs extend from a surface of the web. 
     In one or more additional aspects, in a toothbrush as described in any of the preceding paragraphs, the support structures are formed of a material having a light transmissivity of at least 85% determined using ASTM D1003. 
     In one or more additional aspects, in a toothbrush as described in any of the preceding paragraphs, the handle further comprises a body covering the support structures. 
     In one or more additional aspects, in a toothbrush as described in any of the preceding paragraphs, the body is formed from a material having a light transmissivity of at least 85% determined using ASTM D1003. 
     In one or more additional aspects, in a toothbrush as described in any of the preceding paragraphs, the handle has a light transmissivity of greater than 40% through a portion of the handle comprising the body covering the support structures measure substantially along the direction orthogonal to the longitudinal axis. 
     In additional aspects of this disclosure, a handle for an implement includes a support structure comprising at least one support member extending generally along a longitudinal axis of the handle, the support structure being formed of a first material, and a body disposed on the support structure to cover at least part of the at least one support member, the body being formed of a second material, wherein the handle is at least translucent along a sight line passing through the body and the support structure orthogonal to the longitudinal axis. 
     In one or more additional aspects, in a handle as described in the preceding paragraph, both the first material and the second material have a light transmissivity of at least 85% determined using ASTM D1003. 
     In one or more additional aspects, in a handle as described in any of the preceding paragraphs, at least one of the first material is a clarified polypropylene or the second material is a thermoplastic elastomer. 
     In one or more additional aspects, in a handle as described in any of the preceding paragraphs, the at least one support structure has a thickness in the direction orthogonal to the longitudinal axis of less than 2 millimeters. 
     In one or more additional aspects, in a handle as described in any of the preceding paragraphs, the at least one elongate support structure comprises a web and a plurality of ribs extending from a surface of the web. 
     In one or more additional aspects, in a handle as described in any of the preceding paragraphs, the support structure comprises a plurality of elongate ribs angled relative to each other to form a corrugated structure. 
     In one or more additional aspects, in a handle as described in any of the preceding paragraphs, the at least translucent portion has a visible light transmittance of at least 40%. 
     In one or more additional aspects, in a handle as described in any of the preceding paragraphs, the body is overmolded onto the support structure. 
     Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein: 
         FIG. 1  is a top, plan view of a toothbrush according to an example implementation of this disclosure; 
         FIG. 2  is a cross-sectional view of the toothbrush of  FIG. 1 , taken along section line  2 - 2  in  FIG. 1  and rotated 90-degrees about a longitudinal axis of the toothbrush; 
         FIG. 3  is a top, plan view of a toothbrush according to an example implementation of this disclosure; 
         FIG. 4  is a cross-sectional view of the toothbrush of  FIG. 3 , taken along section line  4 - 4  in  FIG. 3  and rotated 90-degrees about a longitudinal axis of the toothbrush; 
         FIG. 5  is a cross-sectional view of a toothbrush according to an example implementation of this disclosure; 
         FIG. 6  is a cross-sectional view of a toothbrush according to an example implementation of this disclosure; and 
         FIG. 7  is a cross-sectional view of a toothbrush according to an example implementation of this disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses. 
     As used throughout, ranges are used as shorthand for describing each and every value that is within the range. Any value within the range can be selected as the terminus of the range. In addition, all references cited herein are hereby incorporated by referenced in their entireties. In the event of a conflict in a definition in the present disclosure and that of a cited reference, the present disclosure controls. 
     This disclosure relates generally to handles for implements, and more specifically to configurations of a handle for an oral care implement, such as a toothbrush handle. The following detailed description may generally refer to embodiments of a handle as part of a toothbrush, but this disclosure is not limited to use of a handle as a toothbrush handle. Other implements, including but not limited to oral care implements, may incorporate features of this disclosure. In particular implementations, handles according to this disclosure may include transparent or translucent sections. 
       FIGS. 1 and 2  illustrate a toothbrush  100  according to a first implementation of this disclosure. The toothbrush  100  generally includes a handle  102 , a head  104  (which may support bristles, not shown) disposed of the distal end of the handle  102  and a neck portion  106  generally between the handle  102  and the head  104 . As illustrated, the handle has a generally elongate shape, extending along an axis  108 . This disclosure is not limited to the shape and/or size of the toothbrush  100  illustrated in  FIGS. 1 and 2 . In alternative implementations, one or more of the handle  102 , head  104 , and/or neck  106  may have different shapes, sizes, orientations, and/or the like. Additional features may also be incorporated into the toothbrush or disposed on the toothbrush. 
     As illustrated, the handle  102  generally includes a frame  110 , which provides an outer periphery of the handle  102  and defines an inner void or opening. A web  112  extends between sections of the frame  110 , generally along the direction of the axis  108 , and expands across the void. In this embodiment, the web  112  occludes the void completely, although in other embodiments, the web  112  may fill less than the entire void. For example, holes (not illustrated) may be formed through the web  112  to aid in some manufacturing processes, an example of which will be provided below. 
     As also illustrated in  FIGS. 1 and 2 , a plurality of elongate fins or ribs  114  (illustrated as a central rib  114 - 1  and two outer ribs  114 - 2 ) depend from the web  112  and extend generally parallel to the axis  108  from a position proximate an end opposite the head  106  toward the head  106 . In this example, the ribs  114  extend perpendicularly from opposite sides of the web  112 . (As used herein, “perpendicular” and similar terms should be understood to include slight variations, such as things that are “substantially perpendicular.”) As will be appreciated, the ribs  114  may extend at angles other than 90-degrees. Although three ribs  114  are illustrated as extending from each side of the web  112 , more or fewer ribs  114  may alternatively be provided on one or both sides of the web  112 . As also illustrated in  FIG. 1 , the ribs  114  may extend different lengths, i.e., along the axis  108 . In the illustrated example, the central rib  114 - 1  is longer than the other ribs  114 - 2 , extending further along the neck  106 , closer to the head  104 . In other implementations, all of the ribs  114  may be the same length, or they could all be different lengths. The ribs  114  may each have the same height relative to the web  112  or the height may vary from rib to rib. For example, the central rib  114 - 1  may be taller than the outer ribs  114 - 2  to provide a crowned or similar profile across the width of the toothbrush  100 , as shown in  FIG. 2 . Alternatively, or in addition, the height of one or more of the ribs  114  may vary along its length. As illustrated in  FIG. 1 , the ribs may be straight along their length or they may be contoured. In this example, the central rib  114 - 1  is generally straight, extending parallel to the axis  108  of the toothbrush  100 , whereas the outer ribs  114 - 2  on either side of the central rib  114 - 1  more closely follow the contour of the frame  110 . More specifically, at the end of the handle  102  opposite the head  104 , the ribs are generally closer to each other with the outer ribs  114  gradually tapering away from the central rib before tapering back towards the central rib proximate the neck  106 . As will be appreciated by those having skill in the art with the benefit of this disclosure, the number, height, contour, and other attributes of the ribs may be varied to provide different aesthetic and functional benefits. 
     In  FIGS. 1 and 2 , a thickness of each of the web  112  and the ribs  114  may be minimized. In  FIG. 2 , the thickness of the web  112  is indicated as t w  and the thickness of the ribs  114  is indicated as t r . In this example, the thickness t w  is measured in a first direction orthogonal to the axis  108  in and the thickness t r  is measured in a second direction, also orthogonal to the axis  108 , but angled (e.g., by 90-degrees) relative to the first direction. By minimizing their thicknesses, the web  112  and the ribs  114  may be substantially transparent when viewed along a line of sight parallel to the first and second directions, respectively. More specifically, with some materials, as t w  decreases, more light incident on the web will be transmitted through the web  112 . Likewise, as t r  decreases, more light incident on each of the ribs will be transmitted through the ribs  114 . 
     In one example implementation, the toothbrush  100  may be formed from a material having a light transmittance of 85% or more (determined per ASTM D1003). Clarified polypropylene is an example of such a material. Clarified polypropylene provides increased visible light transmission over non-clarified polypropylene, particularly at decreased thicknesses. Thus, in the embodiment illustrated in  FIGS. 1 and 2 , by minimizing the thickness of the web  112  and the ribs  114 , the structure created by the web  112  and the ribs  114  (i.e., in the void) allows more light through than the relatively thicker areas, e.g., the outer frame  110  and the head  106 . Along viewing angles normal to the web and the ribs, the structure is substantially transparent. In some implementations, the web  112  and the ribs  114  have a thickness of less than 2 millimeters and in other embodiments less than 1 millimeter to achieve better light transmittance. As noted above, the thickness of the web  112  and the ribs  114  will affect the light transmission properties of the toothbrush. Other factors, such as the type and amount of clarifier used in the polypropylene and/or other additives, such as dyes or the like, may also affect light transmissivity. 
     Some presently preferred embodiments allow for at least 80% transmittance of light at wavelengths of 410-800 nanometers (i.e., in the visible light spectrum) through portions of the toothbrush  100 . For instance, along a sight line normal to the web, the toothbrush will have a transmittance of 80% or greater. For purposes of this disclosure, as long as one wavelength in the visible light range has greater than 80% transmittance, the toothbrush  100 , is substantially transparent. In other embodiments, toothbrushes in accordance with this disclosure will have a light transmittance of at least 85-90% for light at a wavelength of 410-800 nanometers. For purposes of this disclosure, as long as one wavelength in the visible light spectrum has transmittance greater than a designated amount at any location on the toothbrush, the toothbrush is considered to have a transmittance of at least that amount in the visible light spectrum. Some embodiments allow for at least 40% transmittance of light in the visible light spectrum through substantially all portions of the toothbrush at angles normal to the axis. 
     Light transmissivities described herein may be measured using a spectrophotometer using known techniques. For example, ASTM D1003 describes a technique for measuring light transmissivity through transparent plastics. Although that test is intended for materials having a standard size and shape, similar techniques may be used to measure transmissivity through the toothbrush. 
     The material may also be chosen to limit haze. Haze may also be determined using ASTM D1003, and the material used to manufacture the toothbrush  100  may have a haze value of less than 25%. 
     A number of benefits may be realized by using the clarified polypropylene over conventional clear acrylics or other materials. For instance, clarified polypropylene is generally cheaper than materials conventionally used to make clear parts. Moreover, manufacturing and handling the clarified polypropylene may be easier. Some conventional materials would require longer curing times to form a part like a toothbrush, thus increasing production throughput. Moreover, polypropylene may be readily amenable to further processing. In the example of FIG.  1 , the entire toothbrush  100  is formed as a unitary piece. When that piece is formed of clarified polypropylene, post-processes, such as application of bristles to the head  104 , may be done using conventional techniques. 
     In the example of  FIGS. 1 and 2 , the toothbrush  100  may be a single, unitary part, e.g., formed from a single mold from a single material—clarified polypropylene in one example. More light will be transmitted through the web  112  and the ribs  114  (along a sight line normal to such features, respectively) than through the frame  110  and the head  104 , because the frame and the head are substantially thicker. Thus, the toothbrush  100  will appear substantially transparent along some sight lines, e.g., sight lines normal to the web, and more translucent along other sight lines, e.g., sight lines at other angles, through thicker areas, or through multiple features. In other embodiments, the thickness of the outer frame  110  could be decreased, e.g., to appear more like another rib  114 , which could result in even greater light transmission along sight lines normal to the ribs, passing through the outer frame. Such a design may be less comfortable for a user, but could provide a more light-transmissive aesthetic. 
     In certain embodiments, the head  104  may comprise a plate having a plurality of holes formed therethrough, and tooth cleaning elements may be mounted to the plate within the holes. This type of technique for mounting the tooth cleaning elements to the head  104  via a head plate is generally known as anchor free tufting (AFT). Specifically, in AFT a plate or membrane is created separately from the head  104 . The tooth cleaning elements (such as bristles, elastomeric elements, and combinations thereof) are positioned into the head plate so as to extend through the holes of the head plate. The free ends of the tooth cleaning elements on one side of the head plate perform the cleaning function. The ends of the tooth cleaning elements on the other side of the head plate are melted together by heat to be anchored in place. As the tooth cleaning elements are melted together, a melt matte is formed, which is a layer of plastic formed from the collective ends of the tooth cleaning elements that connects the tooth cleaning elements to one another on one side of the head plate and prevents the tooth cleaning elements from being pulled through the tuft holes. 
     After the tooth cleaning elements are secured to the head plate, the head plate is secured to the head  104  such as by ultrasonic welding. When the head plate is coupled to the head  104 , the melt matte is located between a lower surface of the head plate and a floor of a basin of the head  104  in which the head plate is disposed. The melt matte, which is coupled directly to and in fact forms a part of the tooth cleaning elements, prevents the tooth cleaning elements from being pulled through the holes in the head plate thus ensuring that the tooth cleaning elements remain attached to the head plate during use of the oral care implement  100 . 
     In another embodiment, the tooth cleaning elements may be connected to the head  104  using a technique known in the art as AMR. In this technique, the handle is formed integrally with the head plate as a one-piece structure. After the handle and head plate are formed, the bristles are inserted into holes in the head plate so that free/cleaning ends of the bristles extend from the front surface of the head plate and bottom ends of the bristles are adjacent to the rear surface of the head plate. After the bristles are inserted into the holes in the head plate, the bottom ends of the bristles are melted together by applying heat thereto, thereby forming a melt matte at the rear surface of the head plate. The melt matte is a thin layer of plastic that is formed by melting the bottom end s of the bristles so that the bottom ends of the bristles transition into a liquid, at which point the liquid of the bottom ends of the bristles combine together into a single layer of liquid plastic that at least partially covers the rear surface of the head plate. After the heat is no longer applied, the melted bottom ends of the bristles solidify/harden to form the melt matte/thin layer of plastic. In some embodiments, after formation of the melt matte, a tissue cleaner is injection molded onto the rear surface of the head plate, thereby trapping the melt matte between the tissue cleaner and the rear surface of the head plate. In other embodiments, other structures may be coupled to the rear surface of the head plate to trap the melt matte between the rear surface of the head plate and such structure without the structure necessarily being a tissue cleaner (the structure can just be a plastic material that is used to form a smooth rear surface of the head, or the like, and the structure can be molded onto the rear surface of the head plate or snap-fit (or other mechanical coupling) to the rear surface of the head plate as desired). 
     Of course, techniques other than AFT and AMR can be used for mounting tooth cleaning elements to the head  104 , such as widely known and used stapling/anchoring techniques or the like. In such embodiments the head plate may be omitted and the tooth cleaning elements may be coupled directly to the head  104 . Furthermore, in a modified version of the AFT process discussed above, the head plate may be formed by positioning the tooth cleaning elements within a mold, and then molding the head plate around the tooth cleaning elements via an injection molding process. However, it should be appreciated that certain of the bristle tufts disclosed herein cannot be adequately secured to the head using staple techniques, and one of AFT or AMR is therefore use for securing such bristle tufts (i.e., the conical tufts described below) to the head. 
     Although described herein above with regard to using AFT, in certain embodiments any suitable form of cleaning elements and attachment may be used in the broad practice of this invention. Specifically, the tooth cleaning elements of the present invention can be connected to the head  104  in any manner known in the art. For example, staples/anchors or in-mold tufting (IMT) could be used to mount the cleaning elements/tooth engaging elements. In certain embodiments, the invention can be practiced with various combinations of stapled, IMT, AMR, or AFT bristles. Alternatively, the tooth cleaning elements could be mounted to tuft blocks or sections by extending through suitable openings in the tuft blocks so that the base of the tooth cleaning elements is mounted within or below the tuft block. 
     Although not illustrated herein, in certain embodiments the head  104  may also include a soft tissue cleanser coupled to or positioned on its rear surface. An example of a suitable soft tissue cleanser that may be used with the present invention and positioned on the rear surface of the head  104  is disclosed in U.S. Pat. No. 7,143,462, issued Dec. 5, 2006 to the assignee of the present application, the entirety of which is hereby incorporated by reference. In certain other embodiments, the soft tissue cleanser may include protuberances, which can take the form of one or more ridges (elongated transverse, longitudinal, angled), nubs, or combinations thereof. Of course, the invention is not to be so limited and in certain embodiments the oral care implement  100  may not include any soft tissue cleanser. 
     Generally, in  FIGS. 1 and 2  the web  112  and the ribs  114  may act as support members that collectively form a support structure. The support structure preferably provides stability and a degree of rigidity to the handle  106  for comfortable and effective manual manipulation.  FIGS. 3 and 4  illustrate another embodiment of this disclosure, in which the support structure supports a body, which may be molded over a portion of the handle. 
     More specifically,  FIGS. 3 and 4  illustrate a toothbrush  300  that is substantially the same as the toothbrush  100  (and the same reference numerals are used to identify common components) and further includes a body  302  formed over a portion of the handle  102  and neck  106 . In this example, the body  302  is disposed to completely cover the web  112  and the ribs  114 , on both sides (i.e., the top and bottom) of the toothbrush. The body may be formed to take generally any outer shape and profile, and the dimensions of the body may vary at different positions along the toothbrush. 
     As noted above, some or all of the outer frame  110 , web  112 , and ribs  114  may act as a support structure to provide rigidity to the toothbrush  300 , whereas the body  302  may be chosen to provide a different aesthetic, e.g. to mask the ribs, and/or to provide a different manual gripping surface, e.g., to alter control, comfort, and/or handling. For example, a material having a hardness value of between about 15 and about 90 Shore-A may be selected for its tactile comfort. A low-haze material may also be selected, for its visual aesthetic. For example, a material having a haze value of less than 10% and more preferably less than 5% may be chosen as the material for the body. 
     While a number of conventional materials may be used for the body, in some embodiments the body  302  is made from a material having a light transmittance of 85% or more (determined per ASTM D1003). By way of non-limiting example, the body  302  may be made from a thermoplastic elastomer (TPE) or thermoplastic polymer. TPE having a light transmittance of 90% or higher (determined per ASTM D1003) is commercially available. Moreover, TPE can be readily manufactured, such as through conventional molding, e.g., injection molding, processes, and some TPEs have a haze value of less than about 5%. A suitable TPE for the body  302  may be based on polyolefin-based polymers, styrene block copolymers, and/or a blend of the two. 
     As will be appreciated, when a light transmissive material is used for the body, such as the TPE described above, the overall effect will be a handle that transmits visible light, because both the underlying support structure  100  and the body  302  transmit visible light. The transmissivity of visible light will vary along the toothbrush, e.g., depending upon the thicknesses of the body and the support structure. For example, visible light passing through the neck of the toothbrush along a line of sight normal to the web will have a relatively high transmissivity, and that portion of the toothbrush may be substantially transparent. In contrast, less visible light will pass through the toothbrush along a line of sight that passes through the outer frame  110  and the body  302 . However, because the toothbrush  300  is made from two materials, each having light transmissivity of 85% or higher, some light will pass through the structures made of these materials at conventional toothbrush sizes. Toothbrushes made according to aspects of this disclosure may allow for at least 40% transmittance of light, more preferably 50% transmittance of light, at wavelengths of 410-800 nanometers (i.e., in the visible light spectrum) along substantially any sight line normal to the axis and passing through both the support structure and the body. 
     The toothbrushes  100 ,  300  described above may be manufactured using conventional molding techniques, including but not limited to injection molding. In one example implementation, the toothbrush  100  may be formed in a single mold, as a single shot. In another embodiment, the toothbrush  100  may be formed in two shots, for example, a first shot to create the support structure and a second shot to create the relatively thicker features, e.g., the outer frame  110  and the head  106 . In this example, the second shot may be a different material than the first shot, which may provide additional functionality. For instance, the second shot could be an opaque material, in which case only the area in the void would be at least translucent. Such an arrangement may provide a different aesthetic. 
     When the body  302  is included, as in the toothbrush  300 , the material comprising the body may be overmolded on the toothbrush  100  as support structure. In some embodiments, the body  302  may be formed in a single shot. As one way to promote such a process, holes or the like may be formed in the web  114 , e.g., to allow the material forming the body to pass through to both sides (i.e., the top and bottom) of the toothbrush. In other embodiments, the body  302  may be formed as two or more shots, e.g., a first shot for the body on a first side of the web  112  and a second shot for the body on the other side of the web. 
     According to embodiments of this disclosure, it may be desirable to control the finish on external surfaces of the toothbrush, e.g., to reduce haze. In some examples the TPE body  302  may have a polished surface finish, such as an SPI-A1 or SPI-A2 finish. Such a finish may be achieved by controlling aspects of the molding process. Alternatively, a light surface texture may be applied on the tool to aid in demolding while maintaining a high quality surface. In some embodiments, ejector pins may be staged in the mold, e.g., along the axial direction of the toothbrush, to promote part removal. Ejectors or knock out pins may iteratively de-mold the part along the axial length, to break any vacuum formed between the part and the mold, essentially peeling the mold from the part. Bristles and/or other cleaning implements may also be integrated into the toothbrush  100 ,  300  after molding. 
     The body  302  preferably has good light transmission properties and may advantageously be chemically compatible with the support structure. The body  302  may also take any of a number of shapes, profiles, or appearances. For example,  FIG. 5  shows a cross section of another example toothbrush  500  in which a body  502  is formed to completely encapsulate the support structure. Unlike the body  302  described above, which was formed laterally between the outer frame  110  to leave a portion of the outer frame  110  exposed, the body  502  leaves none of the outer frame  110  exposed. In an alternative to this example, the outer frame  110  may be manufactured to be thinner, e.g., to have a thickness comparable to the ribs, to enhance light transmission through the outer frame. In such an example, the toothbrush may be transparent or semi-transparent when viewed from a side, as well as when viewed from the top or bottom. 
     Although not illustrated in  FIG. 5 , the body  502  may extend axially along the toothbrush  500  any distance. For example, the body  502  may be formed only over the portion of the handle that includes the web and/or ribs or it could extend any distance beyond. In still other embodiments, the ribs may be partially exposed. Moreover, the body  502  may be formed such that some or all of the support structure, e.g., the outer frame, is exposed proximate the end of the toothbrush opposite the head, or such that all the outer frame is encapsulated. 
     Other configurations of the toothbrush  100 ,  300 ,  500  also are contemplated. For example,  FIG. 6  illustrates a toothbrush  600  having a body  602  disposed on a support structure having a cross section different from those described above. The support structure generally includes two (e.g., top and bottom) planar members  604 ,  606  connected by longitudinally extending ribs  608 . The surfaces  604 ,  606  and the extending ribs  608  form a support structure for the body  602 , similar to the embodiments discussed above. As with previously described embodiments, the surfaces  604 ,  606  and the extending ribs  608  preferably are thin enough to allow light transmission therethrough. When clarified polypropylene is used to form the support structure, the surfaces  604 ,  606  and extending ribs  608  may be about two millimeters thick or thinner. In other embodiments, the thickness may be one millimeter or less. 
     Although the body  602  is illustrated as encapsulating the support structure, in other embodiments the body may cover less. For example it may be formed only on the top and/or bottom surfaces of the structure, as in the toothbrush  300 , described above. In some embodiments, the surfaces  604 ,  606  and ribs  608  may be disposed between an outer frame. 
     Another example embodiment is illustrated in  FIG. 7 . Like other embodiments,  FIG. 7  shows a cross-section of a handle  700 . A support structure in this embodiment includes a plurality of ribs  702  extending between an outer frame  704 . The outer frame may take the form of the outer frame  110  described above. The ribs  702  in this example constitute a plurality of support members that together form a corrugated profile. As with embodiments described above, a body may be disposed over some or all of the support structure. Moreover, the outer frame may not be necessary. 
     In each of the examples provided, the support structure includes one or more relatively thin-walled sections, which have higher light transmissivity than relatively thicker sections. When a light-transmissive body is provided over the support structure, the result is a handle having improved light transmission. Although an amount of light transmission will vary along the handle (e.g., based on material thicknesses), some example implementations may allow for at least 40% transmittance of light, more preferably 50% transmittance of light, at wavelengths of 410-800 nanometers (i.e., in the visible light spectrum) along substantially any sight line passing through both the support structure and the body. 
     Although example embodiments have been described in language specific to the structural features and/or methodological acts, the claims are not necessarily limited to the specific features or acts described. Rather, the specific features and acts are disclosed as illustrative forms of implementing the example embodiments.