Image Number 3 for United States Patent #7159951.
A method for manufacturing a brush includes fully and longitudinally filing a bundle of hair into a metal cylinder. One end of the metal cylinder is heated to melt the bundle of hair for forming a combined portion after the melted hair is solidified. The bundle of hair with the combined portion is drawn out from the metal cylinder. At least one through hole is longitudinally defined in the combined portion for outputting material.