Aluminum support for lithographic printing plate

• US 5,832,834 A
• Filed: 07/03/1997
• Issued: 11/10/1998
• Est. Priority Date: 07/05/1996
• Status: Expired due to Term

• Current Assignee: Fuji Photo Film Co Limited (Fujifilm Holdings Corporation)
• Original Assignee: Fuji Photo Film Co Limited (Fujifilm Holdings Corporation)
• Inventors: Uesugi, Akio, Nishino, Atsuo, Fukino, Kiyotaka
• Primary Examiner(s): Funk, Stephen R.
• Application Number:
  US08/888,058
• Time in Patent Office: 495 Days
• Field of Search: 101/454, 101/458, 101/459, 205/106, 205/127, 205/213, 205/214, 205/323, 205/324, 205/658, 428/472.2, 428/687
• US Class Current: 101/459
• CPC Class Codes: B41N 3/034 characterised by the electrochemical treatment of the aluminum support, e.g. anodisation, electro-graining; Sealing of the anodised layer; Treatment of the anodic layer with inorganic compounds; Colouring of the anodic layer
• CPC Class Codes: B82Y 15/00 Nanotechnology for interacting, sensing or actuating, e.g. quantum dots as markers in protein assays or molecular motors
• CPC Class Codes: Y10T 428/12993 Surface feature [e.g., rough, mirror]

Abstract

An aluminum support for a lithographic printing plate used in off-set printing or the like is disclosed, having a surface shape determined using an atomic force microscope (AFM) such that when measured within the measurement range of 100 μm square with the resolution in the horizontal (X, Y) direction being 0.1 μm, assuming that the surface area obtained by an approximate three-point problem is α and the upper projected area is β, the α/β value (specific surface area) is from 1.15 to 1.5, and when measured within the measurement range of 240 μm square with the resolution in the horizontal (X, Y) direction being 1.9 μm, the average surface roughness is from 0.35 to 1.0 μm and the ratio of the sum of the surface area where the gradient of 30° or more to the total surface area is from 5 to 40%.

Claims

1. An aluminum support for a lithographic printing plate having a surface shape determined using an atomic force microscope (AFM) such that

when measured within the measurement range of 100 μ

m square with the resolution in the horizontal (X, Y) direction being 0.1 μ

m, assuming that the surface area obtained by an approximate three-point problem is a and the upper projected area is β

, the α

/β

value (specific surface area) is from 1.15 to 1.5, and

when measured within the measurement range of 240 μ

m square with the resolution in the horizontal (X, Y) direction being 1.9 μ

m, the average surface roughness is from 0.35 to 1.0 μ

m and the ratio of the sum of the surface area where the gradient of 30°

or more to the total surface area is from 5 to 40%.

2. The aluminum support for a lithographic printing plate as claimed in claim 1, wherein the 85°

glossiness according to JIS is 30 or less.

3. The aluminum support for a lithographic printing plate as claimed in claim 2, wherein when the support is observed through a scanning type electron microscope at a magnification of 750 times, honeycomb pits having an average diameter of from 0.5 to 20 μ

m occupy the field of view of 80 μ

m at an area ratio of from 30 to 100%.

4. The aluminum support for a lithographic printing plate as claimed in claim 1, wherein when the support is observed through a scanning type electron microscope at a magnification of 750 times, honeycomb pits having an average diameter of from 0.5 to 20 μ

m occupy the field of view of 80 μ

m at an area ratio of from 30 to 100%.