| 摘要 |
A bristle carrier(7) is placed in a molding tool against a wall in which bristle forming channel-like cavities(3) exist. All cavities are covered by the carrier. A molding material is then introduced at a pressure which enables the material to penetrate through the carrier and fill the bristle-forming cavities. Bristle material may be introduced either in a fluid to plastic state, as a viscoelastic or as a solid material, e.g. powder or granules, which are plasticized under the molding pressure. Material is preferably injected or die cast as a melt through the carrier(7). Bristle material molding pressure is dependent on carrier thickness and material. Some carrier material may be forced into each bristle cavity where it forms a funnel-shaped collar in the widened entry to each cavity. Purged carrier material may form an alloy with the bristle material. Penetration of the carrier can be assisted by weakening features, radially symmetric deliberate weak points or reduced thickness in areas covering the bristle cavities. An additional carrier with preformed holes corresponding to the cavity pattern may be placed in the tool either in front of or behind the first carrier. Carriers may be made of an organic or inorganic material, a film, e.g. metal or plastic foil, at most1mm thick or a 0.2mm thick plate. Carriers may comprise two or more layers of different materials, preferably with different elasticity. Carriers may be a prefabricated part, preferably blow molded, injection molded or thermoformed or can be fed as continuous material to the tool where a carrier section is cut off by tool closure. Bristles may be formed in sections using plastics with different properties and/or color. Bristle material injection pressure can be used to mold a carrier before the pressure penetrates the carrier to enter the bristle cavities. Similarly fluid pressure may be used to initially form the carrier in the tool or carrier material and bristle material may be introduced in a sandwich injection process. Further methods for carrier manufacture either outside or inside the brush molding tool involve gas injection or water injection technology. |
