The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 14, 2006
Filed:
Nov. 10, 2003
Hirofumi Tsutsumi, Kasuya-Gun, Fukuoka, JP;
Teruo Urano, Tochigi, Sano City, JP;
Masatsune Ogura, Ichikawa-City, Chiba, JP;
Tetsuya Shimoda, Hachioji-City, Tokyo, JP;
Hirofumi Tsutsumi, Kasuya-Gun, Fukuoka, JP;
Teruo Urano, Tochigi, Sano City, JP;
Masatsune Ogura, Ichikawa-City, Chiba, JP;
Tetsuya Shimoda, Hachioji-City, Tokyo, JP;
Other;
Abstract
A method of dusting-preventive treatment in which a powder having dusting property is treated with fibril-forming PTFE (polytetrafluoroethylene) to impart non-dusting property thereto and the non-dusting property of the powder, after having been reduced during transportation, are economically and advantageously recovered or improved through a relatively simple step. The method comprises: a first dusting-preventive treatment step in which fibril-forming polytetrafluoroethylene is added to a powder having dusting property, and a compression/shear force is exerted to the mixture at a temperature in the range of 20 to 200° C. to thereby regulate powder so as to have a flow value of 150 mm to 200 mm; and a second dusting-preventive treatment step in which a compression/shear force is exerted again at a temperature in the range of 50 to 150° C., without newly adding fibril-forming polytetrafluoroethylene, to the resultant powder after the powder treated in the first step has deteriorated in dusting-preventive property during transportation with transporting means due to such an external force that the polytetrafluoroethylene fibrils partly cleave or powder particles partly fall off polytetrafluoroethylene fibril nets.