Fuji Photo Film Company, Limited

Fujifilm Corporation

Yasuhiro Annoura

Koichiro Aono

Takanori Masuda

Tsutomu Kato

The present invention provides a planographic printing plate manufacturing apparatus comprising: a cutting process section which cuts a web in a thickness direction of the web by pinching the web with at least a pair of an upper knife and a lower knife, wherein the lower knife includes a flat part supporting a center of the web, a decline part gradually declined an upper end toward outside from the flat part and a cutting edge part having an upper end gradually raised toward outside from the decline part to be a cutting edge, an angle of the lower knife at a boundary point between the decline part and the flat part is 135&#xb0; or more, a boundary point between the decline part and the cutting edge part is provided so as to be greater or equal to a droop width of a lower surface of a cut product.

Planographic printing plate manufacturing apparatus

The present invention discloses a planographic printing plate having a notched portion on its surface having a required size, and having smaller burrs at a rear face, and a planographic printing plate cutting device and a planographic printing plate cutting method for forming such a planographic printing plate by cutting. The planographic printing plate cutting device of the present invention includes an upper roller for forming a recessed section at the planographic printing plate. The upper roller, which is formed substantially into a disc shape as a whole, has a pressing portion parallel to a web (the planographic printing plate), and a slope portion that is slanted with respect to the surface of the web at a predetermined inclination. This upper roller presses the web such that a sloped face (recessed section) that is slanted with respect to the surface of the web is formed. Next, a shearing roller shears the web at the sloped face such that a remaining portion of the sloped face forms a notched portion. Because formation of the notched portion and the shearing process are carried out as separate processes by separate members, a notched portion having a required size can be formed at the surface, and burrs at the rear face can be reduced.

Planographic printing plate machining device, planographic printing plate machining method and planographic printing plate

A clearance between an upper knife and a lower knife of a slitter is set at 30 to 100 &mgr;m, and the slitter cuts a sensitized printing plate. In the sensitized printing plate cut by the slitter, there is a shear droop which is 20 to 30 &mgr;m high at the cut part, and a burr which is less than 50 &mgr;m high. If the maximum height of a surface roughness of a cut surface of the sensitized printing plate is 1.2 &mgr;m to 12 &mgr;m on the average, a hydrophilic property of the cut part improves and the stain of a frame can be decreased.

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Shizuoka, Japan

Yasuhiro Annoura