Patent US2433656A successfully refreshed from Google Patents.
Patent US4873170A successfully refreshed from Google Patents.
US4873170A
Expired / Lapsed
US
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Method for making lithographic printing plate
Assignee: Mitsubishi Paper Mills Ltd
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Filing: 1987-08-06
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Granted: 1989-10-10
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Expires: 2007-08-06
Abstract
Abstract There is provided a method for making a lithographic printing plate having high sensitivity, resolving power and printing endurance and free from scumming utilizing silver complex diffusion transfer process which comprises subjecting to scanning exposure of high-intensity short-time a light sensitive material comprising a support and, provided thereon, at least a silver halide emulsion layer and a physical development nuclei layer as a surface layer and then developing it with a silver complex diffusion transfer developer, the improvement which comprises subjecting the light sensitive material to imagewise exposure with scanning light of at least 700 nm, said emulsion layer containing silver halide grains mainly composed of silver chloride and a sensitizing dye having a sensitivity maximum in the long wavelength region of at least 700 nm in an amount of 3x10-5-3x10-4 mol for 1 mol of silver halide and an antihalation means being provided below said emulsion layer to provide a reflectance of 13-40% for the scanning exposure light of at least 700 nm.
Inventors
- 👤 Hiroshi Nishinoiri
- 👤 Masahiko Saikawa
- 👤 Yoshikazu Takaya
- 👤 Euji Kanada
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 07:02
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/004; G03F7/06; G03F7/07; G03C; G03C8/00; G03C8/02; G03C8/04; G03C8/06; Y; Y10; Y10S; Y10S430/00; Y10S430/145
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
152 words
A method for making a lithographic printing plate utilizing silver complex diffusion transfer process which comprises subjecting to scanning exposure of highintensity short-time a light sensitive material comprising a support and, provided thereon, at least a silver halide emulsion layer and a physical development nuclei layer as a surface layer and then developing it with a silver complex diffusion transfer developer, the improvement which comprises subjecting the light sensitive material to imagewise exposure with scanning light of at least 700 nm, said emulsion layer containing silver halide grains mainly composed of silver chloride and a sensitizing dye having a sensitivity maximum in the long wavelength region of at least 700 nm in an amount of 3×10 -5 -3×10 -4 mol for 1 mol of silver halide and an antihalation means being provided below said emulsion layer to provide a reflectance of 13-40% for the scanning exposure light of at least 700 nm.
Claim 2
Independent Claim
152 words
A method for making a lithographic printing plate utilizing silver complex diffusion transfer process which comprises subjecting to scanning exposure of highintensity short-time a light sensitive material comprising a support and, provided thereon, at least a silver halide emulsion layer and a physical development nuclei layer as a surface layer and then developing it with a silver complex diffusion transfer developer, the improvement which comprises subjecting the light sensitive material to imagewise exposure with scanning light of at least 700 nm, said emulsion layer containing silver halide grains mainly composed of silver chloride and a sensitizing dye having a sensitivity maximum in the long wavelength region of at least 700 nm in an amount of 3×10 -5 -3×10 -4 mol for 1 mol of silver halide and an antihalation means being provided below said emulsion layer to provide a reflectance of 13-40% for the scanning exposure light of at least 700 nm.
Claim 3
Dependent Claim
18 words
A method according to claim 1 wherein the reflectance to be provided by the antihalation means is 14-35%.
Claim 4
Dependent Claim
18 words
A method according to claim 1 wherein an undercoat is provided between the support and the emulsion layer.
Claim 5
Dependent Claim
24 words
A method according to claim 3 wherein the antihalation layer is provided at at least one of the undercoat, the support or backing layer.
Claim 6
Dependent Claim
33 words
A method according to claim 4 wherein the antihalation means is to add to at least one of the layers a material which can absorb a scanning light of at least 700 nm.
Claim 7
Dependent Claim
25 words
A method according to claim 1 wherein the amount of the sensitizing dye is 4×10 -4 -2×10 -4 mol for 1 mol of silver halide.
Claim 8
Dependent Claim
187 words
A method according to claim 1 wherein the sensitizing dye is represented by the following general formula (I), (II), (III) or (IV): ##STR3## wherein Z 1 and Z 2 which may be identical or different represent atom group necessary for formation of 5-membered or 6-membered nitrogen containing heterocyclic ring; R 1 and R 2 which may be identical or different represent alkyl group or alkenyl group; R 3 represents alkyl group, alkenyl group or aryl group; R 4 -R 10 which may be identical or different represent hydrogen atom, halogen atom, alkyl group, aryl group or alkoxy group and R 6 and R 7 or R 8 and R 9 may link to each other to form a 5-membered or 6-membered ring; R 11 and R 12 which may be identical or different represent alkyl group or aryl group and R 11 and R 12 may link to each other to form a 5-membered or 6-membered ring; Y represents sulfur atom, oxygen atom, >N-R 13 (R 13 is an alkyl group); X represents an acid anion; and l, m, n, p and q represent 1 or 2.
References Cited (Backward Citations)
US4144064A
Cited
US4501811A
Cited
US4621041A
Cited
US4621041B1
Cited
US4603100A
Cited
US4770961A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-10-09 | 1993-04-10 | 1993-10-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-10-09 | 1997-04-10 | 1997-10-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-10-09 | 2001-04-10 | 2001-10-10 | $7700.00 | Window Closed / Lapsed |