Abstract: The invention is directed toward a base material for aluminum offset printing plates having improved heat stability comprising an aluminum alloy consisting of from about 0.2 to about 0.6% by weight of iron, less than about 0.25% by weight silicon and copper combined, from about 0.1 to about 0.3% by weight manganese and the remainder being aluminum and trace production impurities, said base material further characterized as containing secondary precipitates in the form of phases of the Al Mn Si: Al Fe: Al Mn type which bear a ratio to one another of from about 1:1:2 to about 1:1:3, the mean particle size being from about 0.25 to about 0.010 micron with a maximum particle size of less than about 0.3 micron and further containing a precipitation structure with a degree of dispersion of less than about 50 phases per cubic micron and a process for producing such material. The sheet material according to this invention may be uniformly roughened in either HCl or HNO.sub.

Abstract: The invention is directed toward a base material for aluminium offset printing plates having improved heat stability comprising an aluminum alloy consisting of from about 0.2 to about 0.6% by weight of iron, less than about 0.25% by weight silicon and copper combined, from about 0.1 to about 0.3% by weight manganese and the remainder being aluminum and trace production impurities, said base material further characterized as containing secondary precipitates in the form of phases of the Al Mn Si: Al Fe: Al Mn type which bear a ratio to one another of from about 1:1:2 to about 1:1:3, the mean particle size being from about 0.25 to about 0.010 micron with a maximum particle size of less than about 0.3 micron and further containing a precipitation structure with a degree of dispersion of less than about 50 phases per cubic micron and a process for producing such material. The sheet material according to this invention may be uniformly roughened in either HCl or HNO.sub.

Abstract: An aluminum alloy suitable as a base for printing plates consists essentially of aluminum containing iron (Fe) and manganese (Mn), the Fe content being 1.2 to 2.1% by weight, the Mn content being 0.1 to 0.9% by weight and the sum of the Fe and Mn contents being 1.3 to 2.2% by weight. A printing plate can be produced with such a base, the base being mechanically, chemically and/or electrochemically roughened and if required, anodically oxidized and hydrophilized. The printing plate includes at least one radiation-sensitive reproduction layer applied on the base.

Abstract: Disclosed is a sheet, foil or strip material comprising aluminum or an alloy thereof, which is first mechanically and then electrochemically roughened on one or both surfaces to produce the following parameters:(a) from about 60 to 90% of the surface comprise a basic structure, in which the arithmetic mean of the distribution of diameters D.sub.a1 of the pits is in the range from about 1 to 5 microns,(b) from about 10 to 40% of the surface comprise a superimposed structure formed of elevations having an average base F from about 100 to 1,500 microns.sup.2, in which the arithmetic mean of the distribution of diameters D.sub.a2 of the pits is in the range from about 0.1 to 1.0 micron,(c) the center line average roughnesses R.sub.a of the entire surface are at least 0.6 micron, and(d) the contact area t.sub.pmi of the entire surface is not more than about 20% at a stylus working depth of 0.125 micron and not more than about 70% at a stylus working depth of 0.4 micron.

Abstract: The present invention describes a light-sensitive copying material comprising a support and a light-sensitive layer which contains from 0.01 to 10 percent by weight of a non-ionic ester which is obtained by reacting a perfluoro-carboxylic acid with a polyalkylene glycol or of an ether which is obtained by reacting a highly fluorinated or a perfluorinated alkanol with a polyalkylene glycol. By the addition of the fluorinated compound, a more uniform coating is achieved, even when one solvent alone is used for the coating solution.