Abstract: Provided is a piezoelectric film capable of realizing a piezoelectric speaker in which a high sound pressure is obtained, a sufficient sound pressure characteristic is obtained in a wide frequency band, and generation of a chattering sound particularly in a low sound can be suppressed. The piezoelectric film is a piezoelectric film including a polymer-based piezoelectric composite material which contains piezoelectric particles in a matrix containing a polymer material, and electrode layers which are laminated on both surfaces of the polymer-based piezoelectric composite material, in which a variation coefficient of a destructive force of a laminate having the polymer-based piezoelectric composite material and the electrode layers in a plane direction is 0.25 or less.

Abstract: An object of the present invention is to provide a cut sheet-like piezoelectric film which includes electrode layers on both surfaces of a piezoelectric layer and is capable of preventing a short circuit of the electrode layers. The object is achieved by providing a cut sheet-like piezoelectric film including a piezoelectric layer which contains piezoelectric particles in a matrix containing a polymer material, and electrode layers which are provided on both surfaces of the piezoelectric layer, in which a distance between the electrode layers at an end portion in a thickness direction is 40% or greater with respect to a thickness of the piezoelectric layer.

Abstract: Provided is a piezoelectric film capable of realizing a piezoelectric speaker in which a high sound pressure is obtained, a sufficient sound pressure characteristic is obtained in a wide frequency band, and generation of a chattering sound particularly in a low sound can be suppressed. The piezoelectric film is a piezoelectric film including a polymer-based piezoelectric composite material which contains piezoelectric particles in a matrix containing a polymer material, and electrode layers which are laminated on both surfaces of the polymer-based piezoelectric composite material, in which a variation coefficient of a destructive force of a laminate having the polymer-based piezoelectric composite material and the electrode layers in a plane direction is 0.25 or less.

Abstract: A plurality of upper slitting blades and a plurality of lower slitting blades are located such that each of the upper slitting blades stands facing one of the lower slitting blades. The upper slitting blade and the lower slitting blade, which stand facing each other, are located such that a cutting edge vicinity region of the upper slitting blade and a cutting edge vicinity region of the lower slitting blade overlap each other in a radial direction. The plurality of the upper slitting blades and the plurality of the lower slitting blades are rotated to slit a magnetic tape web into magnetic tapes. A cutting edge of each of the upper slitting blades and/or a cutting edge of each of the lower slitting blades has a curved shape.

Abstract: A method of cutting a magnetic recording medium comprising the steps of conveying a web by rollers to guide the web to a cutting blade; and cutting the web by the cutting blade in the lengthwise direction of the web so that magnetic recording mediums are formed, wherein a dynamic unbalance of at least a roller immediately before the cutting blade is made to be 20 g or smaller, and the roller guides the web to the cutting blade.

Abstract: A plurality of upper slitting blades and a plurality of lower slitting blades are located such that each of the upper slitting blades stands facing one of the lower slitting blades. The upper slitting blade and the lower slitting blade, which stand facing each other, are located such that a cutting edge vicinity region of the upper slitting blade and a cutting edge vicinity region of the lower slitting blade overlap each other in a radial direction. The plurality of the upper slitting blades and the plurality of the lower slitting blades are rotated to slit a magnetic tape web into magnetic tapes. A cutting edge of each of the upper slitting blades and/or a cutting edge of each of the lower slitting blades has a curved shape.

Abstract: A filter assembly in housing 11 into which a thixotropic fluid is injected for filtration comprises filter layer 14c that is positioned along the central axis and which has the finest mesh, said filter layer 14c being surrounded successively in order by middle filter layer 14b having the next finest mesh and outer filter layer 14a of a coarse mesh. The thixotropic fluid injected into the housing passes through layers 14a, 14b and 14c in that order, whereby the fluid flows out of the housing through one stage of filtration steps.

Abstract: A filter apparatus and coating method particularly adapted for thixotropic coating solutions and which yet permits the dead space within the housing of the filter apparatus for the secondary region to be reduced under a broad range of conditions at all times. The improved filter apparatus has a filter provided within a housing in such a way that it divides the interior of the housing into a primary region into which a coating to be filtered is supplied and a secondary region which receives the coating solution after it is filtered. The apparatus filters the coating solution just before it is coated on a flexible base. The apparatus is characterized in that the housing for the secondary region is designed in such a way that an index for measurement of the dead space within the housing satisfies the relation T/.tau.> 0.95, where .tau. is an experimentally determined dimensionless number for the indicial response time of the housing and T is a dimensionless number of theoretical time.