Abstract: A tape-like magnetic medium comprising a flexible substrate and a magnetic layer thereon which comprises magnetic pigment and polymeric binder. The magnetic layer has a thickness of at least 3 &mgr;m and a specific surface porosity of at least 80 cm2/cm2. Also provided are a production process for the medium and a high-speed process for the production of a copy of a magnetic master tape.

Abstract: A magnetic recording medium which consists of at least two layers cast one on top of the other is described, the lower layer containing acicular magnetic pigments having a field strength of 5-40 kA/m and a magnetization of 20-70 nTm3/g and the upper layer containing a high-density metal powder dispersion. After application of the layers, the magnetic recording medium is subjected to a magnetic disorientation treatment while the layers are in the wet state, so that said recording medium has virtually no magnetic and mechanical anisotropy. The magnetic recording medium produced in this manner is particularly suitable for floppy disks having a high storage capacity of substantially more than 100 megabytes.

Abstract: The present invention relates to a process for coloring polytrimethylene terephthalate fibers by treating the fibers with an aqueous liquor containing at least one dispersing colorant, in the absence of a carrier and the application of pressure. The temperature of the treatment is carried out at or below the boiling point of the liquid, within 20.degree. C. of the boiling point of the liquor. The coloring process begins at a liquor temperature between 20.degree. and 50.degree. C., and the temperature is raised over a period of 20 to 90 minutes. The liquor is then cooled to a temperature between 20.degree. and 50.degree. C., preferably at a rate of cooling of 1.degree. C. per minute, so that at least 95% wt. % of the colorant is absorbed by the fibers, and the dispersing colorant penetrates the fibers to a relative depth of at least 5% with respect to the diameter of the fibers.