SUPPORT FOR LITHOGRAPHIC PRINTING PLATE

PROBLEM TO BE SOLVED: To provide a support for a lithographic printing plate, in which no stain develops in a non-image part regardless of the change of printing conditions and which is excellent in printing performances.

SOLUTION: A support is a plate-like body mainly made of aluminum. The percentage of Al6Fe in an intermetallic compound included in the plate like body is 5% or less or the whole amount of the intermetallic compound or that of α-AlFeSi is 10% or less of the whole amount of the intermetallic compound. At the same time, the density of the ink adhesion portions developed either in spots or in annuli on the surface of the plate-like body after the several times of successive alternate feeding of ink and the dampening water having the chlorine ionic concentration of 0.1 to 5% on the surface of the plate-like body and finally the drying-up of the water content left on the surface of the plate-like body corrsponds with the rating number of 8 to 10 in JIS H8502.

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