Process for making filament having unique tip and surface characteristics

• Main Authors: WEN LI, CHAN JOHN GEOFFREY, RENO ELIZABETH ANN BROWN, CARSON JOHN KIT, MAO XIAOLE
• Format: Patent
• Language: English
• Published: 17.05.2016
• Subjects: AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; BRUSHWARE; HUMAN NECESSITIES; MANUFACTURE OF BRUSHES; MECHANICAL METHODS OR APPARATUS IN THE MANUFACTURE OFARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES ORRIBBONS; NATURAL OR ARTIFICIAL THREADS OR FIBRES; PERFORMING OPERATIONS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; SPINNING; TEXTILES; TRANSPORTING; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

A process for making a filament for use in a brush implement comprises providing a composite filament comprising an external material and at least one internal material, wherein the tip surface comprises the internal material surrounded by the external material, the internal material having longitudinal shrinkage characteristics that differ from those of the external material; and causing the internal material to shrink inside the external material, whereby the internal material comprising the tip surface sinks relative to the external material comprising the tip surface so that at least one crater is formed at the tip surface of the filament, the at least one crater comprising a bottom formed by the internal material and walls formed by the external material, the at least one crater having a surface edge of a predetermined size and a predetermined shape.