公开(公告)号：JPH09111101A

公开(公告)日：1997-04-28

申请号：JP26533195

申请日：1995-10-13

Applicant: TORAY INDUSTRIES

Inventor： OYAMA MASAHIKO ,  OKAWA HIROMOTO ,  HAYASHI GEN

IPC: C08J5/18 ,  C08K3/22 ,  C08K3/26 ,  C08L67/00 ,  C08L67/02

Abstract: PROBLEM TO BE SOLVED: To obtain a polyester composition which can give a film improved in easy slipperiness and wearing resistance by mixing a polyester with a specified calcium carbonate. SOLUTION: A polyester is mixed with 0.005-5.0wt.% calcite calcium carbonate particles having a mean particle diameter of 0.2-1.0μm, a coefficient(%) of particle diameter variation represented by the formula: diameter (X) of disperesed particle/diameter (Y) of agglomerated particle ×100 (where X is the diameter of a particle before being subjected to ultrasonic dispersion treatment, and Y is the diameter of a particle after being subjected to ultrasonic dispersion treatment) of 70-95% and a particle size distribution ratio represented by d25 /d75 of 2, 5 or below (wherein d25 is the particle diameter at a 25% cumulation calculated from the side of larger particle diameters in the cumulative volume distribution curve of particles, and d75 is the particle diameter at a 75% cumulation calculated from the side of larger particle diameters in the cumulative volume distribution curve of particles) and optionally surface-treated with a polycarboxylate and optionally 0.005-5.0wt.% aluminum oxide particles having a mean particle diameter of 0.01-0.3μm.

公开(公告)号：JPH0940850A

公开(公告)日：1997-02-10

申请号：JP19039995

申请日：1995-07-26

Applicant: TORAY INDUSTRIES

Inventor： ODAJIMA AKIO ,  HAYASHI GEN ,  OKAWA HIROMOTO

IPC: C08K3/22 ,  C08G63/181 ,  C08G63/78 ,  C08L67/00

Abstract: PROBLEM TO BE SOLVED: To obtain a polyester composition which particularly shows excellent abrasion resistance and durability, when it is used as a magnetic tape base by adding a slurry prepared by wet-treating 2 or more kinds of aluminum oxide particles different in their crystalline structure. SOLUTION: When polyester is produced using the acid components mainly containing aromatic dicarboxylic acids and the glycol components mainly containing aliphatic glycol, a slurry which is prepared by wet-dispersing two or more kinds of aluminum oxides different in their crystalline structure (suitably particles of 2 or more kinds of activated alumina selected from α-, γ-, δ-, θ-aluminum oxides) in a solvent (preferably the above-stated glycol component) using a phosphorus compound, preferably phosphoric acid, ammonia or a lower amine as a dispersant is added to the polyester at any optional stage. The aluminum oxide particles preferably have a specific surface area of 50-300m /g and the total pore volume of 0.2-1.5ml/g both according to the B.E.T. method.