Method and device for producing a printing block

• US 20020195012A1
• Filed: 05/28/2002
• Published: 12/26/2002
• Est. Priority Date: 05/25/2001
• Status: Active Grant

• Current Assignee: Schablonentechnik Kufstein AG
• Original Assignee: Schablonentechnik Kufstein AG
• Inventors: Juffinger, Josef, Kurz, Franz
• Granted Patent: US 6,857,365 B2
• Time in Patent Office: Days
• US Class Current: 101/401.1
• CPC Class Codes: B41B 19/00 Photoelectronic composing machines
• CPC Class Codes: B41C 1/05 Heat-generating engraving heads, e.g. laser beam, electron beam

Abstract

In the production of a printing block a relief is introduced into the surface of a printing block blank (1) in that material of the printing block blank (1) is removed along tracks by radiation. For this purpose relief regions of different depths along one and the same track in each case are produced by correspondingly frequent exposure to radiation.

Claims

1. Method for producing a printing block in which a relief is introduced into the surface of a printing block blank (1) in that material of the printing block blank (1) is removed along tracks by radiation, characterized in that along one and the same track in each case relief regions located at different depths (A, B, C) are produced by correspondingly frequent exposure to radiation.

2. Method according to claim 1, characterized in that the exposure to radiation ensues with one and the same beam (3) which is guided repeatedly along one track.

3. Method according to claim 1, characterized in that the exposure to radiation ensues by means of a plurality of beams (3, 4, 5) which are guided one after the other along the same track.

4. Method according to claim 3, characterized in that the multiple beams are arranged alongside one another in a direction which runs transverse to the longitudinal direction of the track.

5. Method according to claim 3, characterized in that the multiple beams are arranged alongside one another in a direction which runs in the longitudinal direction of the track.

6. Method according to one of claims 3 to 5, characterized in that relief regions at different depths (A, B, C) are removed by beams of different power.

7. Method according to one of claims 3 to 6, characterized in that relief regions at different depths (A, B, C) are removed by beams of differing wavelength.

8. Method according to claim 6 or 7, characterized in that relief regions (A) located directly on the surface (2) of the printing block blank (1) are removed by beams whose power is less and/or whose wavelength is shorter than that of those beams serving to remove lower-lying relief regions (B, C).

9. Method according to one of claims 1 to 8, characterized in that areas of the material of the printing block blank bounding the surface side of the relief are removed first.

10. Method according to one of claims 1 to 9, characterized in that areas of the material (A) of the printing block blank (1) bounding the surface side of the relief are adapted in their spectral sensitivity to the wavelength of the eroding radiation.

11. Method according to one of claims 1 to 10, characterized in that the exposure of the printing block blank (1) to radiation is effected using laser radiation, eg focused laser radiation.

12. Method according to one of claims 1 to 11, characterized in that the beams are moved relative to the printing block blank (1).

13. Method according to one of claims 1 to 11, characterized in that the printing block blank (1) is moved relative to fixed-position beams.

14. Method according to one of claims 1 to 13, characterized in that a printing block blank possessing a polymer material is irradiated.

15. Method according to claim 14, characterized in that a plate-like printing block blank composed of polymer material is laid on the surface of a rotatably mountable cylinder.

16. Method according to claim 14, characterized in that to form a printing block blank (1) polymer material is pulled onto or applied to the surface of a rotatably mountable cylinder.

17. Method according to one of claims 1 to 16, characterized in that the exposure to radiation of the printing block blank (1) along a track in question ensues as a function of data files (D3, D4, D5) each of which is assigned to one of the relief regions (A, B, C) to be removed located at different depths.

18. Method according to claim 17, characterized in that the data files (D3, D4, D5) are generated as follows:

construction and electronic storage of a two-dimensional basic relief pattern (14);

construction of one or more borders (18, 19) located at different distances from the basic relief pattern to identify relief regions (15, 16, 17) which with increasing distance from the basic relief pattern (14) are intended to be at greater depth;

drawing of a track (A-A) through the enclosed basic relief pattern (14);

searching for boundaries (X3, X4, X5) in the basic relief pattern (14) and the relief regions (15 to 17) on the basis of the borders on the track; and

determination of beam-on and beam-off switching commands on the basis of the discovered boundaries and sorted into respective data files (D3, D4, D5) for the basic relief pattern (14) and the lower-lying relief regions (15 to 17).

19. Method according to claim 18, characterized in that the data files in question (D3 to D5) are used to modulate the beams.

20. Method according to claim 19, characterised in that the respective data files (D3 to D5) have assigned to them in each case different control voltages for modulating the beams.

21. Device for producing a printing block having:

a mounting for holding a printing block blank (1);

an optical device (27) for exposure to radiation of a surface (2) of the printing block blank (1) along a track by means of at least one beam (28) in order by this means to remove regions of the printing block blank (1); and

a control device which by use of a data file containing beam-on and beam-off control commands controls changes in the intensity of the at least single beam on its path along the track,

characterized in that

the control device is constructed in such a way that it provides a plurality of data files (D3 to D5) each containing beam-on and beam-off commands of which each serves for the machining of the printing block blank (1) along the entire track and can be worked through in time-delayed manner.

22. Device according to claim 21, characterized in that the optical device is constructed in such a way that it emits at least one beam (28a) and that the control device is constructed in such a way that in each case one beam passes through one and the same track several times and with every pass of the track a new data file (D3 to D5) can be read out.

23. Device according to claim 21, characterized in that the optical device is constructed in such a way that it emits a plurality of beams (28a to 28c) which are each controllable by only one separate data file (D3 to D5).

24. Device according to claim 23, characterized in that the beams are arranged alongside one another in a direction running transverse to the longitudinal direction of the track.

25. Device according to claim 23, characterized in that the beams are arranged alongside one another in a direction running in the longitudinal direction of the track.

26. Device according to one of claims 21 to 25, characterized in that the beams are laser beams.

27. Device according to one of claims 21 to 26, characterized in that the printing block blank (1) is constructed as a cylinder mounted rotatably about its longitudinal axis which carries on its surface an elastic material, eg polymer material.

28. Device according to claim 27, characterized in that a carriage (23) arranged displaceably in the direction of the longitudinal axis of the cylinder is present which carries at least parts of the optical device.

29. Device according to claim 27, characterized in that the cylinder is displaceable in the direction of its longitudinal axis and the optical device is in a fixed position.

30. Device according to one of claims 21 to 29, characterized in that for controlling the intensity of the beams modulators (30) are provided which are actuable at least indirectly via the data files (D3 to D5).

31. Device according to claim 30, characterized in that a modulator (30a to 30c) in question is connected to at least one analogue switch (37 to 39) through which a control voltage is suppliable to the modulator and that the analogue switch is switchable by the data file (D3 to D5).

32. Device according to claim 31, characterized in that a modulator (30) is connected to the outputs of a plurality of analogue switches (37 to 39) which are each switchable by one of the plurality of data files (D3 to D5) needed for engraving along a track and that the analogue switches (37 to 39) each switch different control voltages (FIG. 7).

33. Device according to claim 31, characterized in that a plurality of modulators (30a to 30c) is present to each of which an analogue switch (37 to 39) is assigned which are each switchable by one of the plurality of data files (D3 to D5) needed for engraving along a track and that the analogue switches each switch different control voltages (FIGS. 8, 9, 10).

34. Device according to one of claims 30 to 33, characterized in that the modulators (30;

30a to 30c) are acousto-optical modulators.

35. Device according to one of claims 30 to 33, characterized in that the modulators are deflectors or beam deflectors.

36. Device according to one of claims 21 to 35, characterized in that the beams are focused beams.