fig1 illustrates one embodiment of the combination bottle and applicator cap according to the present invention , the cap c shown in alignment for interconnection with the neck of a nail polish bottle b . as best shown in fig2 and 3 , cap c is provided with a generally non angular transverse cross section and includes a base member 2 preferably constructed from a material having sufficient rigidity so that the cap c may be firmly threaded onto the neck of a nail polish bottle b . in a preferred embodiment , the base member 2 is constructed from abs copolymers , polypropylene , nylon or another rigid , inflexible material . abs , polypropylene and nylon are preferred materials not only because they are relatively rigid and inflexible , but also because they have been found to form a good bond with the soft overshell material discussed below . suitable polypropylene material may be obtained from basf of germany . the base member 2 includes an exterior side wall 16 , a flange member 18 is provided at a lower end of the base member and a top surface 10 is provided at an opposite , upper end of the base member . raised indicia 6 extends from top surface 10 and may take the form of a decorative marking such as a company logo or other printing . as is apparent , the raised indicia 6 is optional . an interior side wall 20 extends upwardly within base member 2 and terminates at an interior top surface 24 . a portion of interior side wall 20 is provided with female threads 22 adapted to interconnect with the male threads of bottle b . it is within the scope of the present invention to vary the length of interior side wall 20 . for example , the interior side wall 20 may be lengthened so that interior top surface 24 is disposed adjacent top surface 10 of base member 2 . interior top surface 24 is shown in the drawings to include a transversely extending post member 26 configured to be fixedly received within an end 28 of shaft 30 . the opposite end of shaft 30 is provided with a brush 32 . various other embodiments for securing the shaft of the applicator brush to the base member 2 are within the scope of the present invention . for example , rather than rendering the shaft end 28 integral with the shaft 30 as shown in the drawings , a separate connector may be provided that is adapted to be press fitted against the interior side wall 20 of base member 2 and connected to an end of shaft 30 . the overshell member 34 provides a highly tactile and soft material disposed between the user and the rigid portions of the cap and applicator brush . this non - rigid exterior surface enhances the users grip with the cap to reduce or eliminate rotational and translational slippage , provides a damping effect which improves application of the polish from the brush to the nail surface and can be combined with a generally concave surface contour to reduce fatigue during use of the brush . the improvement in overall manual dexterity when using the cap of the present invention will result in a higher quality of brush stroke and application of polish that is substantially improved over that provided by the rigid prior art applicator cap devices . the non - rigid overshell member is preferably formed from a thermoplastic elastomer material and in at least one embodiment has a shore value of about twenty - nine to about ninety - six and a thickness of about 1 mm to about 3 mm . in a preferred embodiment , the overshell will have a shore value of about forty - five and a thickness between about 1 . 5 mm to about 3 . 0 mm . as is apparent , a variety of thicknesses for the overshell material can be provided . for example , the overshell may be applied in a uniform thickness or varied in thickness along the length of the cap . the soft overshell may also be constructed from silicon rubber or other materials adapted to provide the shore values listed and / or function in the manner as required in this disclosure . applicant has discovered that a thermoplastic elastomer material will form a good bond with the above noted materials used to form the rigid base member . the thermoplastic elastomer as set forth above provides an applicator cap having an exterior surface of sufficient feel and resiliency so that not only is surface friction increased and the users grip on the cap improved ; but also , unsteady or unwanted movement of the brush as it contacts the surface will be caused to be damped and minimized . the damping is effected by the slight deflection of the thermoplastic elastomer material forming the overshell . that is , as the cap is held and the brush is stroked against the surface of a nail , the overshell material is adapted to slightly compress against the users fingers to moderate movement of the brush on the nail surface and thereby provide a more steady and uniform brush stroke . the overshell function to reduce translational slip of the cap between the users fingers as the brush is used to apply polish to a surface and rotational slip as in the case where the cap is being twisted onto or off of a bottle . in a preferred embodiment , the thermoplastic elastomer obtained ( advanced elastomer systems ) is sold and marketed under the trademark santoprene . another preferred thermoplastic elastomer may be obtained from gummiwerk kraiburg of germany and is sold and marketed under the trademark thermolast k . a material other than a thermoplastic elastomer is within the scope of the present invention so long as it provides the softness and damping characteristics as set forth above and achieves a high quality bond with the material comprising the underlying base member 2 . overshell member 34 is preferably adhered to the rigid base member 2 using injection molding and in particular , injection molding in accordance with a co - extrusion process . this process employs a mold adapted to receive and cure two separate materials . for example , a polypropylene material is injected into a rotating mold ( not shown ) to form the rigid base member 2 , the mold is then rotated to a second position and a thermoplastic elastomer is injected to form the overshell member . other processes are within the scope of the present invention provided good adhesion is obtained between the overshell and the base member . returning to the drawings and in particular fig2 , overshell 34 is shown to not entirely cover the exterior of the rigid base member 2 . that is , raised indicia 6 on base member 2 extends through openings 36 of overshell 34 . as noted above , this indicia may take the form of a logo or other writing and is of course optional . the exterior surface of flange member 18 is likewise shown to not be covered by overshell 34 and as shown in the drawings , forms a continuous or coplanar surface with the exterior surface of the overshell . flange member 18 is shown to extend laterally from the bottom 38 of cap c to provide an end that is rigid ; however , it is within the scope of the present invention to remove or otherwise modify the flange in view of aesthetic or functional requirements . in another embodiment of the present invention as best shown in fig1 , 2 and 3 , the exterior sidewall 39 of overshell 34 has a concave shape so that the overall thickness of the overshell is variable along the longitudinal axis of cap c . arrows 40 and 42 indicate the regions of the overshell having increased thickness whereas arrow 44 indicates the region of the overshell having a lesser thickness . at least one advantage provided by the concave configuration is an ergonomic fit against the fingertips of a user . if the cap is grasped centrally ( at about arrow 44 ) between a pair of opposed fingers ( or ends thereof ) of the users hand , and a stoke of the brush is effected against the fingernail surface , the thicker regions of the overshell ( at about arrows 40 and 42 ) are caused to be compressed and / or flexed thereby damping the brush stroke and promoting smoother more uniform application of the polish . the compression and / or flexing of the overshell may also occur when the user grasps the cap at or near the end portions identified by arrows 40 and 42 as in the case with a user having a larger or smaller than average finger size . the overshell also functions to diminish translational and rotational slip of the cap as the concave sidewall of the cap is grasped between the ends of the users fingers . rotational slip is a significant problem since nail polish caps almost uniformly are provided with a non - angular transverse cross section . although the base member 2 is shown in the drawings to have substantially cylindrical shape , it is within the scope of the present invention to provide a concave or other shape for the surface of the exterior side wall 16 . turning to fig4 and 5 , another embodiment of the present invention is shown . in the embodiment of fig4 and 5 , base member 2 is preferably constructed from a material having sufficient rigidity so that the cap c may be firmly threaded onto the neck of the cooperating nail polish bottle ( not shown ). as in the earlier embodiments , the base member 2 is preferably constructed from abs plastic , polypropylene , nylon or another rigid , inflexible material that is compatible with the overshell . the base member 2 includes an exterior side wall 16 , a flange member 18 is provided at a lower end of the base member and a top surface 10 is provided at an opposite , upper end of the base member . optional raised indicia 6 is shown to extend from top surface 10 and may take the form of a decorative marking such as a company logo or other printing . an interior side wall 20 extends upwardly within base member 6 and terminates at an interior top surface 24 . a portion of interior side wall 20 is provided with female threads 22 adapted to interconnect with the male threads of a bottle ( not shown ). as in the earlier embodiments , it is within the scope of the present invention to vary the length of interior side wall 20 . also note in this embodiment , the cap does not have a concave shape but is provided with a uniform diameter throughout . interior top surface 24 is shown in the figure to include a transversely extending post member 26 configured to be fixedly received within an end 28 of shaft 30 . the opposite end of shaft 30 is provided with a brush 32 . other embodiments for securing the shaft of the applicator brush to the base member are within the scope of the present invention . in the embodiment of fig4 and 5 , a non - rigid overshell member 35 is provided on the exterior of rigid base member 2 . as in the other embodiments , the overshell member 35 provides a highly tactile and soft material disposed between the fingers of the user and the relatively rigid remaining portions of the cap and applicator brush . the non - rigid exterior surface of the overshell 35 enhances the users grip on the cap by reducing translational and rotational slip as well as improves application of polish from the brush to the nail surface and also functions to reduce fatigue while holding the cap . the exterior of the overshell 35 is provided with indentations or dimples 46 to further enhance the users grip on cap c . it is within the scope of the present invention to provide different surface modification , including but not limited to raised bumps or the like . while it is understood provision of indentations 46 will provide a variable thickness for overshell 35 , it is within the scope of this embodiment to eliminate the indentations ( as in the fig2 ) and provide an overshell 35 having substantially uniform thickness . in such an embodiment , it is understood that the overshell 35 may be sufficiently thick so as to provide the compression and / or flexing as set forth above together with the improved grip surface . in the alternative , the overshell thickness can be lessened and rendered not compressible or flexible in which case the overshell will function to enhance the grip on the cap by providing the anti - slip characteristic . fig6 and 7 illustrate another embodiment of the invention whereby at least a portion of the exterior side wall 16 is shown to project through the exterior side wall 39 of overshell 34 . that is , projection or flange 19 extends from the exterior side wall 16 such that a portion 21 remains uncovered by overshell 34 . various other configurations showing discontinuous side wall surfaces of alternating rigid and non - rigid material are within the scope of the present embodiment . in addition to the above , the flange 19 which does not fully extend around the circumference of base member 2 , provides an abutment 23 against which overshell portion 34 will contact . the contact of the overshell against the flange reduces the likelihood of separation of the overshell from the base member due to torque generated during twisting of the cap onto and off of a bottle . it is also within the teaching of the present invention to provide a separable base member 2 and overshell 34 which may be separately formed and then glued together or otherwise joined together to provide a unitary cap c . further , it is within the scope of the present invention to provide the indicia 6 or some other design on the side walls 16 thereby providing a discontinuous side wall surface having discrete areas of soft and compressible material and separate discrete areas of rigid material continuous with the underlying base cap . this would of course provide a cap c having an enhanced gripping surface limited to certain exterior portions of the cap . it is also within the scope of the present invention to provide other materials for use as the overshell . although the cap may be injection molded with separate materials as set forth above , it may also be injection molded from a single material that increases in density or softness from the interior cap to the exterior surface to thereby provide a rigid underside for support and a good connection with the bottle and the soft and resilient exterior having the gripping and damping characteristics of the present invention . while this invention has been described as having a preferred design , it is understood that it is capable of further modifications , and uses and / or adaptations of the invention and following in general the principle of the invention and including such departures from the present disclosure as come within the known or customary practice in the art to which the invention pertains , and as may be applied to the central features hereinbefore set forth , and fall within the scope of the invention or limits of the claims appended hereto .
a nail polish container and applicator cap comprising a reservoir for containing nail polish to be applied , an opening into the reservoir , an applicator cap for sealing engagement with the opening , the applicator cap operatively associated with an applicator brush , the brush formed from bristles that are aligned in substantially the same direction as the longitudinal axis of the applicator cap , and an overshell of compressible material surrounding the applicator cap , the overshell providing a finger gripping surface on the applicator cap .