(19)
(11) EP 0 428 071 A3

(12) EUROPEAN PATENT APPLICATION

(88) Date of publication A3:
11.12.1991 Bulletin 1991/50

(43) Date of publication A2:
22.05.1991 Bulletin 1991/21

(21) Application number: 90121414.8

(22) Date of filing: 08.11.1990
(51) International Patent Classification (IPC)5B41N 3/03
(84) Designated Contracting States:
DE GB

(30) Priority: 13.11.1989 JP 294421/89
17.01.1990 JP 7525/90

(71) Applicant: FUJI PHOTO FILM CO., LTD.
Kanagawa 250-01 (JP)

(72) Inventors:
  • Kimura, Takeshi, c/o Fuji Photo Film Co., Ltd.
    Haibara-gun, Shizuoka-ken (JP)
  • Sakaki, Hirokazu, c/o Fuji Photo Film Co., Ltd.
    Haibara-gun, Shizuoka-ken (JP)
  • Takamiya, Shuichi, c/o Fuji Photo Film Co., Ltd.
    Haibara-gun, Shizuoka-ken (JP)

(74) Representative: GrÀ¼necker, Kinkeldey, Stockmair & Schwanhäusser Anwaltssozietät 
Maximilianstrasse 58
80538 München
80538 München (DE)


(56) References cited: : 
   
       


    (54) Method for producing substrate for PS plate


    (57) A method for producing a substrate for a presensitized plate for use in making a lithographic printing plate comprises surface-­roughening and anodizing an aluminum plate, wherein the surface-­roughened and anodized aluminum plate is then, in order, subjected to the following treatments:

    (a) a dyeing treatment with a dye;

    (b) a sealing treatment; and

    (c) an optional hydrophilization treatment.

    The method can provide an excellent aluminum substrate for presensitized plates which are excellent in half tone dot reproduction, resistance to background contamination, ability of recovering from contamination with ink and easy achievement of good balance between water and ink and which can correspondingly provide lithographic printing plate having high printing durability.





    Search report