Abstract: The present invention provides a composite film having a linearly-scratched, thin metal film and a plastic film, which has good absorbability to electromagnetic waves in various frequencies, as well as reduced anisotropy in electromagnetic wave absorbability, suitable for electromagnetic wave absorbers, and its production apparatus. The composite film having a linearly-scratched, thin metal film and a plastic film according to the present invention comprises a plastic film, and a single- or multi-layer, thin metal film formed on at least one surface of the plastic film, the thin metal film being provided with large numbers of substantially parallel, intermittent, linear scratches with irregular widths and intervals in plural directions.

Abstract: An apparatus for forming slant, linear easy-to-tear portions on a long plastic film, comprising a roll on which the long plastic film passes, pluralities of pattern rolls each partially having a slant, linear stamp on a rolling surface, a shaft to which pluralities of the pattern rolls are fixed, and a first mechanism for moving the shaft in a direction to the roll. Pressure rolls pushing the pattern rolls via rolls fixed to the shaft. A second moving mechanism for moving the pressure rolls in a direction to the pattern rolls, whereby with the pressure rolls pushing the pattern rolls by the second moving mechanism, the stamp of the pattern rolls are pressed onto the elastic film by the first moving mechanism, so that the slant, linear easy-to-tear portions with recesses formed by the pattern projections of the stamp are provided partially and periodically on the plastic film.

Abstract: An apparatus for periodically forming slant, linear easy-to-tear portions on a long plastic film, comprising a hard roll on which the long plastic film passes, pluralities of pattern rolls each having a slant, linear stamp means on a rolling surface, a motor-driven shaft to which the pattern rolls are fixed, and a mechanism for pushing the pattern rolls toward the hard roll, the movement of the pressure rolls toward the hard roll causing the pattern projections of the stamp means to be pressed onto the plastic film on the hard roll, thereby periodically forming the slant, linear easy-to-tear portions on the plastic film.

Abstract: A method for forming substantially parallel linear scratches on a thermoplastic resin film, comprising bringing the film into sliding contact with a means having a lot of fine projections for forming linear scratches, and pressing the film onto the linear-scratch-forming means from the opposite side of the linear-scratch-forming means by a film-pressing means, in a region in which the film is in sliding contact with the linear-scratch-forming means.

Abstract: The present invention provides a composite film having a linearly-scratched, thin metal film and a plastic film, which has good absorbability to electromagnetic waves in various frequencies, as well as reduced anisotropy in electromagnetic wave absorbability, suitable for electromagnetic wave absorbers, and its production apparatus. The composite film having a linearly-scratched, thin metal film and a plastic film according to the present invention comprises a plastic film, and a single-or multi-layer, thin metal film formed on at least one surface of the plastic film, the thin metal film being provided with large numbers of substantially parallel, intermittent, linear scratches with irregular widths and intervals in plural directions.

Abstract: A method for forming substantially parallel linear scratches on a thermoplastic resin film, comprising bringing the film into sliding contact with a means having a lot of fine projections for forming linear scratches, and pressing the film onto the linear-scratch-forming means from the opposite side of the linear-scratch-forming means by a film-pressing means, in a region in which the film is in sliding contact with the linear-scratch-forming means.

Abstract: A method for forming substantially parallel linear scratches on a thermoplastic resin film, comprising bringing the film into sliding contact with a means having a lot of fine projections for forming linear scratches, and pressing the film onto the linear-scratch-forming means from the opposite side of the linear-scratch-forming means by a film-pressing means, in a region in which the film is in sliding contact with the linear-scratch-forming means.

Abstract: A porous film manufacturing apparatus regularly forms a large number of non-through pores with a fine opening width of sub-.mu.m to several tens .mu.m at a high density in elongated films made of various materials, with almost no deterioration in the essential characteristics of the film materials.

Abstract: This invention provides a porous film useful as a fresh fruit and vegetable wrapping material which is obtained by forming a large number of small recesses in an organic film and which does not allow permeation of water, bacteria, and viruses, but allows permeation of a gas, e.g., the oxygen gas or the carbon dioxide gas, and water vapor. The porous film includes the organic film and the large number of recesses formed in the organic film and having an average opening width of 0.5 .mu.m to 300 .mu.m and inner surfaces exhibiting affinity.

Abstract: This invention provides a porous film useful as a fresh fruit and vegetable wrapping material which is obtained by forming a large number of small recesses in an organic film and which does not allow permeation of water, bacteria, and viruses, but allows permeation of a gas, e.g., the oxygen gas or the carbon dioxide gas, and water vapor. The porous film includes the organic film and the large number of recesses formed in the organic film and having an average opening width of 0.5 .mu.m to 300 .mu.m and inner surfaces exhibiting affinity.