Litho strip and method for its manufacture

US6447982B1 · kind B1 · utility

Assignee

• VAW aluminium AG · DE

Inventors

• Wolfgang von Asten · Pulheim, DE
• Bernhard Kernig · Cologne, DE
• Barbara Grzemba · Bonn, DE

Key dates

• Filing date: Jun 30, 2000
• Grant date: Sep 10, 2002
• Expiry date: Jun 30, 2020

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B41N3/00
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

A litho strip for use as an offset printing plate is described which has a composition of 0.05-0.25% Si, 0.30-0.40% Fe, 0.10-0.30% Mg, max. 0.05% Mn, and max. 0.04% Cu. The strip is produced from a continuous cast ingot of the above composition which is hot rolled to a thickness of up to 2-7 mm. The residual resistance ratio of the hot rolled strip is RR=10-20. The cold rolling is carried out with or without intermediate annealing, wherein the degree of rolling reduction after intermediate annealing is >60%. The further processing up to the EC roughening takes place with the microstructure adjusted in the rolling process at <100&deg; C. The litho strip is characterized by a high thermal stability, a good roughening behavior in the EC processes, and a high reverse bending fatigue strength perpendicular to the rolling direction.