This invention relates to improved mascara brushes in which the bristle filaments are secured together in brush form by a helically twisted metallic wire core. 
A spiral mascara brush of conventional construction comprises a multiplicity of bristles usually consisting of Nylon filaments gripped in a continuous spiral array, such that the free ends of the bristles generally follow a helical pattern much the same as the helix of the twisted wire core itself.  Typically, the core of the brush consists of a unitary metallic wire reversibly folded in a generally U-shaped configuration.  Filaments of approximately twice the length of final bristle heights are disposed between the legs of the U-shaped wire.  The limbs of the wire are then twisted to form a helical core which holds the filaments at their midpoints so as to clamp them in a helical or spiral configuration.  The filaments which usually form the bristles of such a brush are generally cylindrical in shape.  The twisted wire is usually provided with a handle at its outer end which may also serve as the cap or closure for the mascara container.  Brushes of this type are well known in the art and have been widely used up to the present time. 
The general purpose of a mascara brush is to pickup a supply of mascara or some other cosmetic medium, carry it from the container and then apply the mascara to the user's eyelashes.  For this purpose, it is important to have a brush in which its bristle tips are uniformly distributed throughout the bristle face of the brush.  It is also important that the bristles be capable of readily picking up an ample supply of mascara at one time and effectively carrying or holding the same until the mascara is transferred to the eyelashes.  It is also important that the bristles have sufficient flexural strength to comb the mascara through the eyelashes of the user. 
It has been known in the paintbrush art, to use bristles of tapered cruciform and other cross-sectional configurations.  U.S. Pat.  No.  3,344,457 discloses a number of such paintbrush filaments.  But these filaments are merely incorporated into the brush by gluing them into the ferrule of the paintbrush in parallel relationship. 
U.S. Pat.  No.  4,561,456 discloses an injection molded mascara brush in which the bristles have hooked or enlarged tip portions to increase the cosmetic product retained by so-called capillarity.  Of course, brushes of this type would require expensive and complicated tooling to effect such molding results. 
In accordance with this invention, the bristle material used is a hollow or tubular polyamide or one which has a noncircular cross-section which extend radially from a twisted wire core.  The hollow or noncircular bristles may either be used alone or in combination with other bristles of regular cylindrical cross-section. 
The principal object of this invention is to provide an improved mascara brush which may be fabricated by a conventional twisted wire technique but which provides for more uniform radial distribution of the brush tips a the bristle face than was heretofore available. 
It is another object of this invention to provide an improved mascara brush which has enhanced capability of media pickup and retention for more effective cosmetic application to the eyelashes of the user.