Claims
- 1. Printing apparatus comprising:
- a. a printing member having a printing surface and including a solid oleophobic layer and a solid oleophilic layer underlying the oleophobic layer, one of said layers being characterized by ablative absorption of imaging radiation;
- b. means for supporting the printing member;
- c. at least one laser source that produces an imaging output;
- d. means for guiding the output of the at least one laser to focus on the printing surface;
- e. means for causing relative movement between the guiding means and support means to effect a scan of the printing surface by the laser output; and
- f. means for selectably actuating, in a pattern representing an image, the laser source so as to ablate the absorptive layer, thereby removing or facilitating removal of the oleophobic layer and directly producing on the member an array of image features.
- 2. Printing apparatus comprising:
- a. a printing member having a printing surface and including a first solid layer, a second solid layer underlying the first layer, and a solid substrate underlying the second layer, the first layer and substrate having different affinities for at least one printing liquid selected from the group consisting of ink and an abhesive fluid for ink, the second layer, but not the first layer, being formed of a material being subject to ablative absorption of imaging radiation;
- b. at least one laser source that produces an imaging output;
- c. means for guiding the output of the at least one laser to focus on the printing surface;
- d. means for causing relative movement between the guiding means and the member to effect a scan of the printing surface by the laser output; and
- e. selectable actuation means for removing or facilitating removal of, in a pattern representing an image, the first and second layers by exposing the printing surface to the laser output during the course of the scan.
- 3. Printing apparatus comprising:
- a. at least one print station including:
- i. a plate cylinder;
- ii. a printing plate having a printing surface and including a solid oleophobic layer and a solid oleophilic layer underlying the oleophobic layer, one of said layers being characterized by ablative absorption of imaging radiation;
- iii. means for mounting the plate to the plate cylinder;
- iv. at least one laser source that produces an imaging output;
- v. means for guiding the output of the at least one laser to focus on the printing surface;
- vi. means for causing relative movement between the guiding means and plate to effect a scan of the printing surface by the laser output;
- vii. means for selectably actuating, in a pattern representing an image, the laser source so as to ablate the absorptive layer, thereby removing or facilitating removal of the oleophobic plate layer and directly producing on the plate an array of image features; and
- b. means for transferring a recording medium to the print station.
- 4. Printing apparatus comprising:
- a. at least one print station including:
- i. a plate cylinder;
- ii. a printing plate having a printing surface and including a first solid layer, a second solid layer underlying the first layer, and a solid substrate underlying the second layer, the first layer and substrate having different affinities for at least one printing liquid selected from the group consisting of ink and an abhesive fluid for ink, the second layer, but not the first layer, being formed of a material being subject to ablative absorption of imaging radiation;
- iii. means for mounting the plate to the plate cylinder;
- iv. at least one laser source that produces an imaging output;
- v. means for guiding the output of the at least one laser to focus on the printing surface;
- vi. means for causing relative movement between the guiding means and the plate to effect a scan of the printing surface by the laser output;
- vii. means for selectably removing or facilitating removal of, in a pattern representing an image, the first and second plate layers by exposing the printing surface to the laser output during the course of the scan; and
- b. means for transferring a recording medium to the print station.
- 5. The apparatus of claim 1 or 2 wherein the output of each laser reaches the printing surface by means of a single print array.
- 6. The apparatus of claim 5 wherein the apparatus comprises a plurality of laser sources and the outputs are arranged linearly within the print array.
- 7. The apparatus of claim 5 wherein the apparatus comprises a plurality of laser sources and the outputs are arranged diagonally within the print array.
- 8. The apparatus of claim 1 or 2 wherein each guiding means is a fiber-optic cable.
- 9. The apparatus of claim 1 or 2 wherein each guiding means is a lens array positioned between the laser source and the printing surface.
- 10. The apparatus of claim 1 or 2 wherein the selectable-actuation means includes a pulse circuit that operates at speeds of at least 40,000 pulses/second.
- 11. The apparatus of claim 1 or 2 wherein each laser source outputs a power level of at least 0.2 megawatt/in.sup.2.
- 12. The apparatus of claim 1 or 2 wherein each laser source emits primarily in the near-IR region.
- 13. The apparatus of claim 1 or 2 wherein each laser source is an infrared semiconductor laser.
- 14. The apparatus of claim 1 or 2 wherein the member is supported on a drum.
- 15. The apparatus of claim 1 or 2 wherein the member is suppported on a flatbed support.
- 16. The apparatus of claim 3 or 4 wherein the at least one print station further comprises:
- a. an ink train for transferring ink to the plate cylinder; and
- b. means for transferring ink from the plate cylinder to the recording medium.
- 17. The apparatus of claim 3 or 4 wherein the apparatus comprises a plurality of print stations arranged in an in-line configuration.
- 18. The apparatus of claim 3 or 4 wherein the apparatus comprises a plurality of print stations arranged in a central-impression configuration.
- 19. The apparatus of claim 2 or 4 wherein the laser output ablates the second layer, thereby facilitating removal of the first layer.
- 20. A method of imaging a lithographic printing member, the method comprising the steps of:
- a. providing a printing member having a printing surface and including a solid oleophobic layer and a solid oleophilic layer underlying the oleophobic layer, one of said layers being characterized by ablative absorption of imaging radiation;
- b. spacing at least one laser source that produces an imaging output opposite the printing surface;
- c. guiding the output of the at least one laser to focus on the printing surface;
- d. causing relative movement between the laser output and the printing member to effect a scan of the printing surface by the laser output; and
- e. selectively exposing, in a pattern representing an image, the printing surface to the laser output during the course of the scan so as to ablate the absorptive layer, thereby removing or facilitating removal of the oleophobic layer and directly producing on the member an array of image features.
- 21. A method of printing with a printing press that includes means for supporting a lithographic printing member, the method comprising the steps of:
- a. providing a printing member having a printing surface and including a first solid layer, a second solid layer underlying the first layer, and a solid substrate underlying the second layer, the first layer and substrate having different affinities for at least one printing liquid selected from the group consisting of ink and an abhesive fluid for ink, the second layer, but not the first layer, being formed of a material being subject to ablative absorption of imaging radiation;
- b. mounting the printing member to the support means;
- c. spacing at least one laser source that produces an imaging output opposite the printing surface of the printing member;
- d. guiding the output of the at least one laser to focus on the printing surface;
- e. causing relative movement between the laser output and support means to effect a scan of the printing surface;
- f. selectively exposing, in a pattern representing an image, the printing surface to the laser output during the course of the scan so as to selectably remove or facilitate removal of the first and second layers;
- g. applying ink to the member; and
- h. transferring the ink to a recording medium.
- 22. A method of printing with a printing press that includes a plate cylinder, the method comprising the steps of:
- a. providing a printing plate having a printing surface and including a solid oleophobic layer and a solid oleophilic layer underlying the oleophobic layer, one of said layers being characterized by ablative absorption of imaging radiation;
- b. mounting the plate to the plate cylinder;
- c. spacing at least one laser source that produces an imaging output opposite the printing surface of the plate;
- d. guiding the output of the at least one laser to focus on the printing surface;
- e. causing relative movement between the laser output and the printing plate to effect a scan of the printing surface by the laser output;
- f. selectively exposing, in a pattern representing an image, the printing surface to the laser output during the course of the scan so as to ablate the absorptive layer, thereby removing or facilitating removal of the oleophobic plate layer and directly producing on the plate an array of image features;
- g. applying ink to the plate; and
- h. transferring the ink to a recording medium.
- 23. A method of imaging a lithographic printing member, the method comprising the steps of:
- a. providing a printing member having a printing surface and including a first solid layer, a second solid layer underlying the first layer, and a solid substrate underlying the second layer, the first layer and substrate having different affinities for at least one printing liquid selected from the group consisting of ink and an abhesive fluid for ink, the second layer, but not the first layer, being formed of a material being subject to ablative absorption of imaging radiation;
- b. spacing at least one laser source that produces an imaging output opposite the printing surface of the printing member;
- c. guiding the output of the at least one laser to focus on the printing surface;
- d. causing relative movement between the laser output and the printing member to effect a scan of the printing surface; and
- e. selectively exposing, in a pattern representing an image, the printing surface to the laser output during the course of the scan so as to selectably remove or facilitate removal of, in a pattern representing an image, the first and second layers.
- 24. The method of claim 20 or 21 wherein the selectable-exposure step occurs at a rate of at least 40,000 pulses/second.
- 25. The method of claim 20 or 21 further comprising the step of operating each laser source at an output power level of at least 0.2 megawatt/in.sup.2.
- 26. The method of claim 20 or 21 wherein each laser source emits primarily in the near-IR region.
- 27. The method of claim 20 or 21 wherein each laser source is a semiconductor laser.
- 28. The method of claim 22 or 21 wherein the selectable-exposure step occurs at a rate of at least 40,000 pulses/second.
- 29. The method of claim 22 or 21 further comprising the step of operating each laser source at an output power level of at least 0.2 megawatt/in.sup.2.
- 30. The method of claim 22 or 21 wherein each laser source emits primarily in the near-IR region.
- 31. The method of claim 22 or 21 wherein each laser source is a semiconductor laser.
- 32. The method of claim 23 or 21 wherein the second layer is ablated, thereby facilitating removal of the first layer.
RELATED APPLICATION
This is a continuation of Ser. No. 07/917,481, filed Jul. 20, 1993, now abandoned.
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Continuations (1)
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Number |
Date |
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Parent |
917481 |
Jul 1993 |
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