(19)
(11) EP 0 474 460 A3

(12) EUROPEAN PATENT APPLICATION

(88) Date of publication A3:
12.08.1992 Bulletin 1992/33

(43) Date of publication A2:
11.03.1992 Bulletin 1992/11

(21) Application number: 91308055.2

(22) Date of filing: 03.09.1991
(51) International Patent Classification (IPC)5: G03G 15/09
(84) Designated Contracting States:
DE FR GB IT

(30) Priority: 04.09.1990 JP 232396/90

(71) Applicant: MITA INDUSTRIAL CO., LTD.
Osaka 540 (JP)

(72) Inventors:
  • Nishino, Toshio
    Nara-shi, Nara-ken (JP)
  • Tomita, Shoji
    Yao-shi, Osaka-fu (JP)

(74) Representative: Senior, Alan Murray et al
J.A. KEMP & CO., 14 South Square, Gray's Inn
London WC1R 5LX
London WC1R 5LX (GB)


(56) References cited: : 
   
       


    (54) Developing process


    (57) Disclosed is a developing process, which comprises forming a magnetic brush of a two-component developer comprising a magnetic carrier and a toner on a developing sleeve and bringing the magnetic brush into sliding contact with a photosensitive material having a charged image to form a toner image on the photosensitive material, wherein in advance to the sliding contact with the photosensitive material, portions having a low pack density (27) of the developer and portions having a high pack density (25) of the developer are alternately formed on the developing sleeve in the circumferential direction.
    According to this developing process, a contact frequency between the developing sleeve and the photosensitive material drum can be properly adjusted without drastic lamination of the earing length of the magnetic brush or the drum-sleeve distance, and an image having a high density can be obtained. Developing sleeve with the grooves (24) extending in axial direction used.






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