Letterpress printing machine

Abstract

A letterpress printing machine is disclosed including a rotary printing cylinder in which a relief printing plate is installed, a substrate surface plate on which a substrate is placed, an ink supply device supplying ink on the relief printing plate, a relief printing plate washing equipment washing the surface of the relief printing plate, and a wiper for a plate. The relief printing plate washing equipment can include a washing liquid supplying unit, an air blasting unit jetting pressurized gas to the relief printing plate, a suction unit sucking the washing liquid scattered by air blasting unit, and a washing liquid recovery unit.

Description

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic diagram which shows a letterpress printing machine in example 1.

FIG. 2 is a schematic diagram of a plate washing device included in a letterpress printing machine of example 1 in operation mode.

FIG. 3 is a schematic diagram of a wiper for a plate in a letterpress printing machine of example 1 in operation mode.

FIG. 4 is a schematic diagram of a printing cylinder, a dispenser mechanism and a substrate surface plate used in flexographic printing.

FIG. 5 is a block diagram of a letterpress printing machine in example 2.

FIG. 6 is an illustration of a letterpress printing machine of example 2 in operation mode.

FIG. 7 is an illustration of printing nip width of letterpress printing machine in example 2.

FIG. 8 shows the belt-shaped pattern which is installed in substrate so that printing pressure is constant.

FIG. 9 is a letterpress printing machine (a flexographic printer) for luminescent layer formation of an organic electroluminescent display device in operation mode.

FIG. 10 is a letterpress printing machine (a flexographic printer) for luminescent layer formation of an organic electroluminescent display device in operation mode.

Claims

1. A letterpress printing machine comprising a rotary printing cylinder in which a relief printing plate is installed, a substrate surface plate on which a substrate is placed, an ink supply device supplying ink to the relief printing plate, a relief printing plate washing equipment washing the surface of the relief printing plate, a wiper for a plate which wipes off washing liquid on the relief printing plate after washing, wherein the relief printing plate washing equipment includes a washing liquid supplying unit supplying washing liquid to the surface of the relief printing plate, an air blasting unit jetting pressurized gas to the relief printing plate to which the washing liquid is supplied, a suction unit sucking the washing liquid scattered by the air blasting unit, and a washing liquid recovery unit receiving the washing liquid supplied to the surface of the relief printing plate.

2. The letterpress printing machine according to claim 1, wherein the washing liquid supplying unit supplies only washing liquid to the surface of the relief printing plate without the washing liquid supplying unit touching the relief printing plate.

3. The letterpress printing machine according to claim 1, wherein supplying point of the washing liquid is between a bottom point of the printing cylinder to a top point of the printing cylinder.

4. The letterpress printing machine according to claim 1, wherein the washing liquid supplying unit includes a washing liquid spray nozzle jetting the washing liquid in the surface of the relief printing plate, the air blasting unit includes a gas injection nozzle jetting the pressurized gas to the relief printing plate after the washing liquid is jetted, the suction unit includes a suction hole sucking a splash of the washing liquid,wherein the washing liquid spray nozzle, the gas injection nozzle and the washing liquid recovery unit are accommodated in a cover,wherein shape of the cover is shape corresponding to an outer circumferential curved surface of the printing cylinderand wherein the cover opens only at a part corresponding to the curved surface, and a gap between the outer circumferential curved surface of the printing cylinder and the part corresponding to the curved surface is less than 5 mm.

5. The letterpress printing machine according to claim 4, wherein the washing liquid spray nozzle and the gas injection nozzle face the open part of the cover, and the washing liquid spray nozzle and the gas injection nozzle are arranged just before and after direction of rotation of the printing cylinder.

6. The letterpress printing machine according to claim 1, wherein a common nozzle is used as the nozzle of the washing liquid supplying unit and the nozzle of the air blasting unit, and washing liquid and pressurized gas can be jetted selectively from this single nozzle.

7. The letterpress printing machine according to claim 1, wherein the wiper for the plate includes wiping sheet feed means which sends the washing liquid wiping sheet which is a long film, wipe means to wipe off the washing liquid which sticks to the relief printing plate by wiping sheet touching the relief printing plate, and wiping sheet recovery means to wind wiping sheet off after having wiped off the washing liquid sticking to the relief printing plate.

8. A letterpress printing machine including a rotary printing cylinder having a relief printing plate, a substrate surface plate on which a substrate is placed and an ink supply device supplying ink on the relief printing plate, wherein the machine has a mechanism for keeping printing pressure between the relief printing plate and the substrate within a printing face constant.

9. The letterpress printing machine according to claim 8, wherein the mechanism has an up and down movement means which senses change of printing pressure between the relief printing plate and the substrate and moves up/down the printing cylinder and/or the substrate surface plate depending on the change of the printing pressure in order to keep the printing pressure constant.

10. The letterpress printing machine according to claim 9, wherein the printing cylinder and/or the substrate surface plate is supported by the up and down movement means at two or more points, and the up and down movement means are operated at each supporting point independently.

11. The letterpress printing machine according to claim 9, wherein the up and down movement means is a pneumatic actuator or hydraulic actuator.

12. The letterpress printing machine according to claim 9, wherein the substrate surface plate is a rotary impression cylinder.

13. The letterpress printing machine according to claim 8, wherein the printing cylinder moves up and down by sensing the change of the printing cylinder.

14. A letterpress printing machine comprising a rotary printing cylinder in which a relief printing plate is installed, a surface plate on which a substrate is placed and ink supply means supplying ink to the surface of the relief printing plate, wherein ink supply means is placed between a contact point of the relief printing plate and the substrate, and a position of right angle just before the contact point of the printing cylinder,and wherein ink supply means faces a surface of the printing cylinder.

15. The letterpress printing machine according to claim 14, wherein the ink supply means includes an anilox roll supplying ink on the relief printing plate, an ink pot and a doctor,wherein ink pot has an ink storage and an opening, and the ink storage maintains a lower surface part of the anilox roll in dipping condition, and a surface part of the anilox roll which does not soak in ink storage protrudes from the opening to direction of the relief printing plate,and wherein the doctor scrapes off unnecessary ink stuck to a surface of the anilox roll.

16. The letterpress printing machine according to claim 15, wherein a gap between the opening and a surface of the anilox roll is less than 2 mm.

17. The letterpress printing machine according to claim 15, wherein the ink pot is connected with a ink tank through an ink supplement pipe and an ink supplement pump.

18. The letterpress printing machine according to claim 17, wherein ink is supplied from the ink tank to the ink pot by driving regularly the ink supplement pump according to number of printing times.