SURFACE SHAPE MEASURING METHOD FOR LONG-SIZED BODY AND ITS MEASURING INSTRUMENT AS WELL AS PRODUCTION OF LONG-SIZED BODY AND PRODUCTION OF MAGNETIC RECORDING MEDIUM

摘要

PROBLEM TO BE SOLVED: To provide such a surface shape measuring method of a long-sized body which is capable of quantitatively determining elongation and slack by accurately measuring the elongation and slack in the transverse direction of a base film in the production stage of a magnetic tape and using the results of the measurement for improvement of stages and as management indices as well as a process for producing the long-sized body and a process for producing a magnetic recording medium. ;SOLUTION: The base film 70 sampled to a prescribed width is stretched and fixed in the slit part 54b of a stand 54 and tension is imparted thereon by a weight 72. A plane state is formed on the base film 70 and the surface shape in the transverse direction on the base film 70 is picked up by using a pickup means 62 and is outputted. The production conditions for the base film 70 are controlled in accordance with the measurement result by the output, by which the surface shape thereof is controlled to a nondefective surface shape within a permissible range.;COPYRIGHT: (C)1999,JPO