PRINTING METHOD AND PRINTING PRESS
An ink supplying unit supplies a water-based ink having a predetermined water content set in advance. An ink form roller receives the water-based ink from the ink supplying unit. A plate cylinder is in contact with the ink form roller, and receives the water-based ink from the ink form roller. A water-content decreasing unit decreases the water content of the water-based ink on the ink form roller.
1 . A printing press comprising:
an ink supplying unit that supplies a water-based ink having a predetermined water content set in advance;
an ink form roller that receives the water-based ink from the ink supplying unit;
a plate cylinder that is in contact with the ink form roller, and receives the water-based ink from the ink form roller; and
a water-content decreasing unit that decreases the water content of the water-based ink on the ink form roller.
2 . The printing press according to claim 1 , wherein the water-content decreasing unit includes
a cover that covers a transferred portion of the ink form roller where the water-based ink is transferred, and
a first dehumidifying unit that dehumidifies a space portion covered by the cover.
3 . The printing press according to claim 1 , further comprising a first water-content increasing unit that increases the water content of the water-based ink on the plate cylinder.
4 . The printing press according to claim 3 , further comprising:
a blanket cylinder that is in contact with the plate cylinder, and transfers the water-based ink supplied on the plate cylinder onto a printing medium as a printing image; and
a second water-content increasing unit that increases the water content of the water-based ink on the blanket cylinder.
5 . The printing press according to claim 4 , wherein the second water-content increasing unit increases the water content of the printing paper before printing the printing image.
6 . The printing press according to claim 3 , wherein the first water-content increasing unit includes
a cover that covers a transferred portion of the plate cylinder where the water-based ink is transferred; and
a humidifying unit that humidifies a space portion covered by the cover.
7 . The printing press according to claim 4 , wherein the second water-content increasing unit includes
a cover that covers a transferred portion of the blanket cylinder where the water-based ink is transferred and a portion of the printing paper; and
a humidifying unit that humidifies a space portion covered by the cover.
8 . The printing press according to claim 3 , further comprising a dehumidifying unit that dehumidifies a surface of the plate cylinder after the water-based ink is transferred.
9 . The printing press according to claim 1 , further comprising:
a peripheral humidity detecting unit that detects a peripheral humidity around the ink form roller and the plate cylinder; and
a control unit that controls the water-content decreasing unit based on the peripheral humidity detected by the peripheral humidity detecting unit.
10 . The printing press according to claim 9 , further comprising a space-portion humidity detecting unit that detects a humidity in a space portion covered by the cover, wherein
the control unit controls the water-content decreasing unit to adjust the humidity in the space portion detected by the space-portion humidity detecting unit to be an optimal humidity that is set based on the peripheral humidity detected by the peripheral humidity detecting unit.
11 . The printing press according to claim 1 , wherein
a plurality of printing units each including the ink supplying unit, the ink form roller, and the plate cylinder is arranged along a feeding direction of the printing paper,
a humidifying unit that humidifies the printing paper is provided at least on an uppermost stream side of the printing units, and
a dehumidifying unit that dehumidifies the printing paper is provided at least on a lowermost stream side of the printing units.
12 . A printing press comprising:
an ink supplying unit that supplies a oil-based ink having a predetermined water content set in advance;
an ink form roller that receives the oil-based ink from the ink supplying unit;
a plate cylinder that is in contact with the ink form roller, and receives the oil-based ink from the ink form roller; and
a water-content increasing unit that increases the water content of the oil-based ink on the ink form roller.
13 . The printing press according to claim 12 , wherein the water-content increasing unit includes
a cover that covers a transferred portion of the ink form roller where the oil-based ink is transferred, and
a humidifying unit that humidifies a space portion covered by the cover.
14 . The printing press according to claim 12 , further comprising a first water-content decreasing unit that decreases the water content of the oil-based ink on the plate cylinder.
15 . The printing press according to claim 14 , further comprising:
a blanket cylinder that is in contact with the plate cylinder, and transfers the oil-based ink supplied on the plate cylinder onto a printing medium as a printing image; and
a second water-content decreasing unit that decreases the water content of the oil-based ink on the blanket cylinder.
16 . The printing press according to claim 15 , wherein the second water-content decreasing unit decreases the water content of the printing paper before printing the printing image.
17 . The printing press according to claim 15 , wherein the first water-content decreasing unit includes
a cover that covers a transferred portion of the plate cylinder where the oil-based ink is transferred; and
a dehumidifying unit that dehumidifies a space portion covered by the cover.
18 . The printing press according to claim 16 , wherein the second water-content decreasing unit includes
a cover that covers a transferred portion of the blanket cylinder where the water-based ink is transferred and a portion of the printing paper; and
a dehumidifying unit that dehumidifies a space portion covered by the cover.
19 . A printing method comprising:
supplying a water-based ink having a predetermined water content set in advance to an ink form roller; and
forming an image of the water-based ink by transferring the water-based ink on the ink form roller onto a plate cylinder while decreasing the water content of the water-based ink on the ink form roller.
20 . A printing method comprising:
supplying a oil-based ink having a predetermined water content set in advance to an ink form roller; and
forming an image of the oil-based ink by transferring the oil-based ink on the ink form roller onto a plate cylinder while increasing the water content of the oil-based ink on the ink form roller.