US5109771A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Spark-discharge lithography plates containing image-support pigments
Assignee: Presstek LLC
•
Filing: 1989-11-28
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Granted: 1992-05-05
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Expires: 2009-11-28
Abstract
Abstract A lithographic printing plate that is transformable by spark-discharge techniques so as to change its affinity for ink. The plate features a layered structure including an ink-receptive substrate, a conductive layer and an ink-repellent coating. The ink-repellent coating contains a dispersion of crystalline metal oxide particles that promote straight-line travel of the spark to the surface of the plate, thereby promoting accurate imaging.
Inventors
- 👤 Thomas E. Lewis
- 👤 Michael T. Nowak
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 09:12
CPC Classifications
B; B41; B41C; B41C1/00; B41C1/10; B41C1/1008; B41C1/1033; B41P; B41P2227/00; B41P2227/70; B41P2235/00; B41P2235/10; B41P2235/20; B41P2235/23
Claims Analysis
Total Claims: 54
Claim 1
Independent Claim
51 words
A lithographic plate that is transformable so as to change the affinity of said plate for ink, said plate being a layered structure including an ink-receptive substrate, a conductive layer and an ink-repellent coating, said coating containing a dispersion of particles consisting essentially of at least one crystalline metal oxide compound.
Claim 2
Dependent Claim
51 words
A lithographic plate that is transformable so as to change the affinity of said plate for ink, said plate being a layered structure including an ink-receptive substrate, a conductive layer and an ink-repellent coating, said coating containing a dispersion of particles consisting essentially of at least one crystalline metal oxide compound.
Claim 3
Dependent Claim
23 words
The plate of claim 1 wherein said crystalline metal oxide compound contains at least two metal ions or atoms of different oxidation states.
Claim 4
Dependent Claim
18 words
The plate of claim 2 wherein said at least two metal ions or atoms are the same metal.
Claim 5
Dependent Claim
17 words
The plate of claim 2 wherein said at least two metal ions or atoms are different metals.
Claim 6
Dependent Claim
13 words
The plate of claim 2 Wherein said oxidation states are +2 and +3.
Claim 7
Dependent Claim
24 words
The plate of claim 1 wherein said crystalline metal oxide compound contains at least two metal ions or atoms of the same oxidation state.
Claim 8
Dependent Claim
85 words
The plate of claim 3 wherein said at least one crystalline metal oxide compound comprises at least one member of the group consisting of Fe 3 O 4 , gamma Fe 2 O 3 , Co 3 O 4 , Mn 3 O 4 , CrO 2 , ZnO, MnO 2 , MoO 2 , NbO 2 , SnO 2 , CuO, Cu 2 O, TiO, Ti 2 O 3 , V 2 O 3 , VO 2 , WO 2 and WO 3 .
Claim 9
Dependent Claim
17 words
The plate of claim 3 wherein said crystalline metal oxide compound comprises Fe 3 O 4 .
Claim 10
Dependent Claim
16 words
The plate of claim 3 wherein said crystalline metal oxide compound comprises gamma Fe2O 3 .
Claim 11
Dependent Claim
17 words
The plate of claim 3 wherein said crystalline metal oxide compound comprises Co 3 O 4 .
Claim 12
Dependent Claim
17 words
The plate of claim 3 wherein said crystalline metal oxide compound comprises Mn 3 O 4 .
Claim 13
Dependent Claim
15 words
The plate of claim 3 wherein said crystalline metal oxide compound comprises CrO 2 .
Claim 14
Dependent Claim
13 words
The plate of claim 3 wherein said crystalline metal oxide compound comprises ZnO.
Claim 15
Dependent Claim
15 words
The plate of claim 3 wherein said crystalline metal oxide compound comprises MnO 2 .
Claim 16
Dependent Claim
15 words
The plate of claim 3 wherein said crystalline metal oxide compound comprises MoO 2 .
Claim 17
Dependent Claim
15 words
The plate of claim 3 wherein said crystalline metal oxide compound comprises NbO 2 .
Claim 18
Dependent Claim
15 words
The plate of claim 3 wherein said crystalline metal oxide compound comprises SnO 2 .
Claim 19
Dependent Claim
14 words
The plate of claim 3 wherein said crystalline metal oxide comprises Cu 2 O.
Claim 20
Dependent Claim
12 words
The plate of claim 3 wherein said crystalline metal oxide comprises CuO.
Claim 21
Dependent Claim
13 words
The plate of claim 3 wherein said crystalline metal oxide compound comprises TiO.
Claim 22
Dependent Claim
17 words
The plate of claim 3 wherein said crystalline metal oxide compound comprises Ti 2 O 3 .
Claim 23
Dependent Claim
17 words
The plate of claim 3 wherein said crystalline metal oxide compound comprises V 2 O 3 .
Claim 24
Dependent Claim
15 words
The plate of claim 3 wherein said crystalline metal oxide compound comprises VO 2 .
Claim 25
Dependent Claim
15 words
The plate of claim 3 wherein said crystalline metal oxide compound comprises WO 2 .
Claim 26
Dependent Claim
15 words
The plate of claim 3 wherein said crystalline metal oxide compound comprises WO 3 .
Claim 27
Dependent Claim
92 words
The plate of claim 4 wherein said at least one crystalline metal oxide compound comprises at least one member of the group consisting of CoCr 2 O 4 , CuCr 2 O 4 , MnCr 2 O 4 , NiCr 2 O 4 , LaCrO 3 , Fe,Mn(Fe,Mn) 2 O 4 , Fe,Mn(Fe,Mn) 2 O 4 :CuO, Cu(Fe,Cr) 2 O 4 , CuFe 2 O 4 , CuCr 2 O 4 , CoFe 2 O 4 , NiFe 2 O 4 , MgFe 2 O 4 and MnFe 2 O 4 .
Claim 28
Dependent Claim
17 words
The plate of claim 4 wherein said crystalline metal oxide compound comprises CoCr 2 O 4 .
Claim 29
Dependent Claim
17 words
The plate of claim 4 wherein said crystalline metal oxide compound comprises MnCr 2 O 4 .
Claim 30
Dependent Claim
17 words
The plate of claim 4 wherein said crystalline metal oxide compound comprises NiCr 2 O 4 .
Claim 31
Dependent Claim
15 words
The plate of claim 4 wherein said crystalline metal oxide compound comprises LaCrO 3 .
Claim 32
Dependent Claim
17 words
The plate of claim 4 wherein said crystalline metal oxide compound comprises Fe,Mn(Fe,Mn) 2 O 4 .
Claim 33
Dependent Claim
17 words
The plate of claim 4 wherein said crystalline metal oxide compound comprises Fe,Mn(Fe,Mn) 2 O 4 :CuO.
Claim 34
Dependent Claim
17 words
The plate of claim 4 wherein said crystalline metal oxide compound comprises Cu(Fe,Cr) 2 O 4 .
Claim 35
Dependent Claim
17 words
The plate of claim 4 wherein said crystalline metal oxide compound comprises CuFe 2 O 4 .
Claim 36
Dependent Claim
17 words
The plate of claim 4 wherein said crystalline metal oxide compound comprises CuCr 2 O 4 .
Claim 37
Dependent Claim
17 words
The plate of claim 4 wherein said crystalline metal oxide compound comprises CoFe 2 O 4 .
Claim 38
Dependent Claim
17 words
The plate of claim 4 wherein said crystalline metal oxide compound comprises NiFe 2 O 4 .
Claim 39
Dependent Claim
17 words
The plate of claim 4 wherein said crystalline metal oxide compound comprises MgFe 2 O 4 .
Claim 40
Dependent Claim
17 words
The plate of claim 4 wherein said crystalline metal oxide compound comprises MnFe 2 O 4 .
Claim 41
Dependent Claim
18 words
The plate of claim 1 wherein said crystalline metal oxide compound is a high-temperature superconductor or related precursor.
Claim 42
Dependent Claim
67 words
The plate of claim 40 wherein said at least one crystalline metal oxide compound comprises at least one member of the group consisting of Ba 2 CuO 3 , Ba 2 Ca 3 Cu 4 O 9 , Bi 2 Sr 2 CaCu 2 O 8+x , La 2 CuO 4 and YB a 2 Cu 3 O 7-x , wherein x ranges from 0.1 to 0.5.
Claim 43
Dependent Claim
18 words
The plate of claim 40 wherein said crystalline metal oxide compound comprises B a 2 CuO 3 .
Claim 44
Dependent Claim
22 words
The plate of claim 40 wherein said crystalline metal oxide compound comprises B a 2 Ca 3 Cu 4 O 9 .
Claim 45
Dependent Claim
28 words
The plate of claim 40 wherein said crystalline metal oxide compound comprises Bi 2 Sr 2 CaCu 2 O 8+x , wherein x ranges from 0.1 to 0.5.
Claim 46
Dependent Claim
17 words
The plate of claim 40 wherein said crystalline metal oxide compound comprises La 2 CuO 4 .
Claim 47
Dependent Claim
23 words
The plate of claim 40 wherein said crystalline metal oxide compound comprises YB a 2 Cu3O7-x wherein x ranges from 0.1 to 0.5.
Claim 48
Dependent Claim
32 words
The plate of claim 1 wherein the lattice of said crystalline metal oxide compound contains a physical feature extending across a crystal grain, which feature provides a low-energy pathway for electron migration.
Claim 49
Dependent Claim
36 words
The plate of claim 1 wherein the lattice of said crystalline metal oxide compound contains metal and oxygen atoms or ions placed such that metal d orbital and oxygen p or π p orbital overlap occurs.
Claim 50
Dependent Claim
40 words
The plate of claim 1 wherein the potential energy of the lattice of said crystalline metal oxide compound is not appreciably elevated by delocalization of one or more d-orbital electrons from the metal atom or ion into a conduction band.
Claim 51
Independent Claim
170 words
A method of imaging a lithographic plate having a printing surface and including a surface layer containing selective filler material, a thin metal layer and a substrate, comprising the steps of: a. mounting the plate to the plate cylinder of a lithographic press having at least one plate cylinder, a corresponding number of blanket cylinders and an impression cylinder; b. exposing the surface layer to spark discharges between the plate and an electrode spaced close to the printing surface produced in response to picture signals representing an image, the spark discharges producing sufficient heat to remove the surface layer and the thin metal layer from the substrate at the points thereof exposed to the spark discharges; c. moving the electrode and the plate relatively to effect a scan of the printing surface; d. controlling the spark discharges to the plate in accordance with picture signals so that they occur at selected times in the scan; and e. causing straight-line travel of the spark discharges as they emerge from the electrode.
Claim 52
Independent Claim
170 words
A method of imaging a lithographic plate having a printing surface and including a surface layer containing selective filler material, a thin metal layer and a substrate, comprising the steps of: a. mounting the plate to the plate cylinder of a lithographic press having at least one plate cylinder, a corresponding number of blanket cylinders and an impression cylinder; b. exposing the surface layer to spark discharges between the plate and an electrode spaced close to the printing surface produced in response to picture signals representing an image, the spark discharges producing sufficient heat to remove the surface layer and the thin metal layer from the substrate at the points thereof exposed to the spark discharges; c. moving the electrode and the plate relatively to effect a scan of the printing surface; d. controlling the spark discharges to the plate in accordance with picture signals so that they occur at selected times in the scan; and e. causing straight-line travel of the spark discharges as they emerge from the electrode.
Claim 53
Independent Claim
163 words
An apparatus for producing a lithographic plate comprising: a. a lithographic plate blank having a printing surface and including a surface layer, a thin metal layer and a substrate; b. a lithographic press having at least one plate cylinder to which the plate blank is mounted, a corresponding number of blanket cylinders and an impression cylinder; c. an electrode spaced close to the printing surface for producing spark discharges in response to picture signals representing an image, the spark discharges creating sufficient heat to remove the thin metal layer from the substrate at the points thereof exposed to the spark discharges; d. means for moving the electrode and the plate blank relatively to effect a scan of the printing surface; and e. means for controlling the spark discharges to the plate blank in accordance with picture signals so that they occur at selected times in the scan, wherein the surface layer promotes straight-line travel of the spark as it emerges from the electrode.
Claim 54
Independent Claim
163 words
An apparatus for producing a lithographic plate comprising: a. a lithographic plate blank having a printing surface and including a surface layer, a thin metal layer and a substrate; b. a lithographic press having at least one plate cylinder to which the plate blank is mounted, a corresponding number of blanket cylinders and an impression cylinder; c. an electrode spaced close to the printing surface for producing spark discharges in response to picture signals representing an image, the spark discharges creating sufficient heat to remove the thin metal layer from the substrate at the points thereof exposed to the spark discharges; d. means for moving the electrode and the plate blank relatively to effect a scan of the printing surface; and e. means for controlling the spark discharges to the plate blank in accordance with picture signals so that they occur at selected times in the scan, wherein the surface layer promotes straight-line travel of the spark as it emerges from the electrode.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-05-05 | 1995-11-04 | 1996-05-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-05-05 | 1999-11-04 | 2000-05-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-05-05 | 2003-11-04 | 2004-05-05 | $7700.00 | Window Closed / Lapsed |