NON-ASBESTOS FIBER OPENING METHOD, NON-ASBESTOS FIBER KNEADING METHOD AND JOINT SHEET

PROBLEM TO BE SOLVED: To enhance dispersability by opening non-asbestos fibers used when a joint sheet is molded by kneading non-asbestos fibers along with a rubber binder, a vulcanizing agent and a filler by using an opening machine. SOLUTION: When a joint sheet is produced, at first, opened non-asbestos fibers 1B obtained by opening non-asbestos fibers 1 by an opening machine 1A such as an Eirich mixer, a Loedige mixer or an impact grinder, a rubber binder 2, a vulcanizing agent 3 and a filler 4 are kneaded by a kneader in a first step A and the kneaded mixture is aged in a second step B and weighed in a thirst step C. Subsequently, the kneaded mixture is molded into the joint sheet in a fourth step D and the joint sheet is finally finished in a fifth step E. Since non-asbestos fibers 1 are opened by the opening machine 1A to be kneaded as opened non-asbestos fibers 1B, dispersibility at a time of kneading is good and the high tensile strength by uniform dispersion can be obtained.