US4294672A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for preparing a support for a lithographic printing plate
Assignee: Fujifilm Holdings Corp
•
Filing: 1980-05-30
•
Granted: 1981-10-13
•
Expires: 2000-05-30
Abstract
Abstract A method for preparing a support for a planographic printing plate using an electrolytic surface treatment of an aluminum plate is disclosed, wherein an alternating charge voltage is applied to the aluminum plate in an acidic electrolyzing bath, and the wave form representing the voltage includes an intermission of zero voltage in at least one of the anode or the cathode phases, and is such that the electric quantity for the anode phase is larger than the electric quantity for the cathode phase.
Inventors
- 👤 Hisao Ohba
- 👤 Kazutaka Oda
- 👤 Yukio Yabuta
- 👤 Azusa Ohashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 07:23
CPC Classifications
C; C25; C25F; C25F3/00; C25F3/02; C25F3/04; B; B41; B41N; B41N3/00; B41N3/03; B41N3/034; H; H05; H05K; H05K3/00; H05K3/38; H05K3/382; H05K3/44; Y; Y10; Y10S; Y10S204/00; Y10S204/09
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
83 words
A method for preparing a support for a lithographic printing plate comprising electrolytically graining an aluminum plate in an acidic electrolyzing bath, wherein an alternating charge voltage having a wave form which includes at least one intermission period of zero voltage in at least one of the anode or the cathode phases is applied to said plate, and is such that the electric quantity for the anode phase Q a is larger than the electric quantity for the cathode phase Q c .
Claim 2
Independent Claim
83 words
A method for preparing a support for a lithographic printing plate comprising electrolytically graining an aluminum plate in an acidic electrolyzing bath, wherein an alternating charge voltage having a wave form which includes at least one intermission period of zero voltage in at least one of the anode or the cathode phases is applied to said plate, and is such that the electric quantity for the anode phase Q a is larger than the electric quantity for the cathode phase Q c .
Claim 3
Dependent Claim
30 words
A method for preparing a support for a lithographic printing plate as in claim 1, wherein the temperature during said electrolytic graining is maintained between about 20° and 40° C.
Claim 4
Dependent Claim
31 words
A method for preparing a support for a lithographic printing plate as in claim 1, wherein said intermission period of zero voltage takes place at the start of a polarity phase.
Claim 5
Dependent Claim
33 words
A method for preparing a support for a lithographic printing plate as in claim 1, wherein said wave form includes one intermission in said anode phase and one intermission in said cathode phase.
Claim 6
Dependent Claim
32 words
A method for preparing a support for a lithographic printing plate as in claim 4, wherein said intermission periods occur at the beginning of the anode phase and the cathode phase, respectively.
Claim 7
Dependent Claim
40 words
A method for preparing a support for a lithographic printing plate as in claim 1, 3, 4, or 5, wherein said intermission period is from about 5 to 40% of the total time of the phase within which it occurs.
Claim 8
Dependent Claim
36 words
A method for preparing a support for a lithographic printing plate as in claim 6, wherein said intermission period is from 10 to 30% of the total time of the polarity phase within which it occurs.
Claim 9
Dependent Claim
48 words
A method for preparing a support for a lithographic printing plate as in claim 1, 3, 4, or 5, wherein said aluminum plate is an aluminum alloy containing at least one member selected from the group consisting of Si, Cu, Mn, Mg, Cr, Zn, Pb, Bi, and Ni.
Claim 10
Dependent Claim
29 words
A method for preparing a support for a lithographic printing plate as in claim 1, wherein the ratio of Q c /Q a is from about 0.3/1 to 0.8/1.
Claim 11
Dependent Claim
31 words
A method for preparing a support for a lithographic printing plate as in claim 1, wherein the range for the ratio of Q c /Q a is from 0.6/1 to 0.7/1.
Claim 12
Dependent Claim
33 words
A method for preparing a support for a lithographic printing plate as in claim 1, wherein the maximum voltages for the anode phase and cathode phase are between about 10 and 50 volts.
Claim 13
Dependent Claim
48 words
A method for preparing a support for a lithographic printing plate as in claim 1, wherein current density through the aluminum plate during the cathode phase is from about 10 to 70 amp/dm 2 and during the anode phase is from about 5 to 50 amp/dm 2 .
Claim 14
Dependent Claim
48 words
A method for preparing a support for a lithographic printing plate as in claim 1, wherein the current density through the aluminum plate during the cathode phase is from 12 to 36 amp/dm 2 , and during the anode phase is from 7 to 21 amp/dm 2 .
Claim 15
Dependent Claim
38 words
A method for preparing a support for a lithographic printing plate as in claim 1, wherein the net total quantity of electricity generated with the aluminum plate as the anode is from 100 to 4000 coulomb/dm 2 .
Claim 16
Dependent Claim
38 words
A method for preparing a support for a lithographic printing plate as in claim 14, wherein the net total quantity of electricity generated with the aluminum plate as the anode is from 400 to 2,400 coulomb/dm 2 .
References Cited (Backward Citations)
US2930741A
Cited
US3520788A
Cited
US3073765A
Cited
DE1446026A1
Cited
US3887447A
Cited
US4140599A
Cited
JPS5219124A
Cited
US4087341A
Cited
US4072589A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-10-12 | 1985-04-13 | 1985-10-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-10-12 | 1989-04-13 | 1989-10-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-10-12 | 1993-04-13 | 1993-10-13 | $7700.00 | Window Closed / Lapsed |