| 摘要 |
884,204. Agglutinated fibrous materials; laminates. MINNESOTA MINING & MANUFACTURING CO. Feb. 21, 1958 [Feb. 21, 1957], No. 5737/58. Class 140. [Also in Group XXIII] An abrasive article comprises a non-woven open skeletal structure of resilient springy fibrous members incorporating an adhesive, randomly bonding members to each other, and abrasive grains also bonded to the members, the article containing from 75 to 95% by volume of uniformly distributed voids. Specified fibres are nylon, polyethylene terephthalate and latex - treated cotton threads. Specified abrasives are silicon carbide, aluminium oxide, cerium oxide, emery, quartz and tripoli. Specified adhesives are a solution of phenol aldehyde resin in ethylene glycol monoethyl ether, an epoxy resin consisting of the reaction product of bisphenol A and epichlorhydrin, maleic anhydride-propylene glycol polyesters, rigid polyurethane resins, animal glue, polystyrene, polyvinyl chloride, polyacrylates and polyamides. As shown, fibres 11 form a non- woven skeletal mat structure (Fig. 2), which includes void spaces 12, and are bonded together by adhesive globules 21 with which are associated abrasive granules 22. A disc cut from such a mat may be provided with a hub with an opening for the insertion of a driving shaft. The face of the disc may be used for abrading; or several discs may be mounted on the shaft and optionally adhered together, to form a roll whose surface may be used for abrading. The abrasive material according to the invention may be made by forming a skeletal structure of fibres supported by an open weave carrier web, passing the structure under a spray nozzle which applies an atomised cloud of adhesive particles containing abrasive grains in suspension, and then through an oven containing radiant heating elements. Heated air, in passing through the oven, is diverted by baffles to pass twice through the fibrous structure and carrier web. The carrier web is then removed and wound up and a fresh carrier web is applied to the treated face of the fibrous structure which then undergoes a second similar treatment and is finally separated from the second carrier web and wound up. Instead of applying the adhesive-mineral slurry to the fibrous structure by spraying, it may be roll.coated directly on to the structure; or the adhesive may be applied by spraying or roll coating and the mineral subsequently sifted in. The abrasive material of the invention may be adhered to a suitable support member such as cloth, paper, plastic film or vulcanized fibre. An endless polishing belt may be formed in such manner. |
