Cosmetic brush comprising bristles having external depressions

Abstract

A cosmetic brush and a process of making same. The brush comprises a substantially longitudinal stem and a plurality of bristles, each bristle extending from a base associated with the stem and terminating with a free end, each bristle having external walls and a longitudinal axis, the brush further having a major axis disposed along the stem, wherein the plurality of bristles comprises selected bristles, each of the selected bristles having at least one external depression oriented in a direction substantially parallel to the longitudinal axis of the selected bristle. The process comprises the steps of forming a hollow stem from a first moldable material; providing a plurality of bristle-forming channels surrounding and abutting the hollow stem, each of the bristle-forming channels, the plurality of bristle-forming channels comprising selected bristle-forming channels having at least one protuberance; injecting a second moldable material into the hollow stem under pressure sufficient to rapture the hollow stem in predetermined locations corresponding to the bristle-forming channels and to fill the bristle-forming channels with the second moldable material; and solidifying the second moldable material.

1 . A cosmetic brush comprising a substantially longitudinal stem and a plurality of bristles, each bristle extending from a base associated with the stem and terminating with a free end, each bristle having external walls and a longitudinal axis, the brush further having a major axis disposed along the stem, wherein the plurality of bristles comprises selected bristles, each of the selected bristles having at least one external depression oriented in a direction substantially parallel to the longitudinal axis of the selected bristle.  
   
   
       2 . The brush according to  claim 1 , wherein the selected bristle has a generally oblong shape in a cross-section perpendicular to the longitudinal axis of the selected bristle.  
   
   
       3 . The brush according to  claim 1 , wherein the external walls of the at least some bristles comprise a surface selected from the group consisting of a flat surface, a convex surface, a concave surface, or any combination thereof.  
   
   
       4 . The brush according to  claim 1 , wherein the at least one external depression extends from the base of the selected bristle to the free end thereof.  
   
   
       5 . The brush according to  claim 1 , wherein the at least one external depression extends from the base of the selected bristle toward the free end thereof but does not reach the free end of the selected bristle.  
   
   
       6 . The brush according to  claim 1 , wherein the at least one external depression extends from the free end of the selected bristle toward the base thereof but does not reach the base of the selected bristle.  
   
   
       7 . The brush according to  claim 1 , wherein the at least one external depression is disposed intermediate but reaches neither of the base and the free end of the selected bristle.  
   
   
       8 . The brush according to  claim 1 , wherein the bristles have differential lengths.  
   
   
       9 . The brush according to  claim 1 , wherein the ends of at least three bristles consecutively disposed next to one another in a cross-section of the brush form a line selected from the group consisting of a straight line, a concave line, a convex line, or any combination thereof, the cross-section of the brush being perpendicular to the major axis.  
   
   
       10 . The brush according to  claim 1 , wherein at least some of the bristles gradually taper from the base towards the free end.  
   
   
       11 . The brush according to  claim 1 , wherein the free ends of at least some of the bristles have a concave depression therein.  
   
   
       12 . The brush according to  claim 1 , wherein the longitudinal axes of at least some of the bristles and the major axis of the brush are mutually perpendicular.  
   
   
       13 . The brush according to  claim 1 , wherein the brush is made by a process including injection molding.  
   
   
       14 . A process for making a cosmetic brush comprising a substantially longitudinal stem and a plurality of bristles extending therefrom, the process comprising steps of: 
 (a) providing a hollow stem from a first moldable material;    (b) providing a plurality of bristle-forming channels surrounding and abutting the hollow stem, each of the bristle-forming channels terminating with an end and having a length, the plurality of bristle-forming channels comprising selected bristle-forming channels, each of the selected bristle-forming channels having at least one protuberance therein;    (c) injecting a second moldable material into the hollow stem under pressure sufficient to rapture the hollow stem in predetermined locations corresponding to the bristle-forming channels and to fill the bristle-forming channels with the second moldable material so that the second moldable material assumes the shape of the bristle-forming channels;    (e) solidifying the second moldable material disposed in the bristle-forming channels thereby forming the plurality of bristles of the brush being made, wherein the plurality of bristles comprises selected bristles formed in the selected channels and having at least one external depression thereon.    
   
   
       15 . The process according to  claim 14 , wherein in the step of providing a plurality of bristle-forming channels, the protuberances are disposed along the length of the selected bristle-forming channels.  
   
   
       16 . The process according to  claim 14 , wherein in the step of providing a plurality of bristle-forming channels, the protuberances are disposed at the free end of the selected bristle-forming channels.  
   
   
       17 . The process according to  claim 14 , wherein the step of providing a plurality of bristle-forming channels comprises a step of providing a plurality of plates disposed side-by-side consecutively in an abutting relation to one another, wherein mutually abutting plates have surface patterns that form, in combination, a desired profile of the bristle-forming channels.  
   
   
       18 . The process according to  claim 14 , wherein in the step of forming a hollow stem from a first moldable material and in the step of injecting a second moldable material, the first moldable material and the second moldable material are identical.  
   
   
       19 . The process according to  claim 14 , wherein in the step of forming a hollow stem from a first moldable material and in the step of injecting a second moldable material, the first moldable material and the second moldable material differ from one another.  
   
   
       20 . The process according to  claim 14 , further comprising a step of filling the hollow stem with a third moldable material.