EP0389229A2 - Appareil de formation d'images - Google Patents

Appareil de formation d'images Download PDF

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Publication number
EP0389229A2
EP0389229A2 EP90302946A EP90302946A EP0389229A2 EP 0389229 A2 EP0389229 A2 EP 0389229A2 EP 90302946 A EP90302946 A EP 90302946A EP 90302946 A EP90302946 A EP 90302946A EP 0389229 A2 EP0389229 A2 EP 0389229A2
Authority
EP
European Patent Office
Prior art keywords
developer
developer carrier
image forming
forming apparatus
carrier
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP90302946A
Other languages
German (de)
English (en)
Other versions
EP0389229A3 (fr
Inventor
Satoshi Matsumoto
Shinobu Nakata
Hideshi Ishihara
Hiroshi Terada
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Panasonic Holdings Corp
Original Assignee
Matsushita Electric Industrial Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from JP1069665A external-priority patent/JPH02248969A/ja
Priority claimed from JP1095749A external-priority patent/JPH0789252B2/ja
Priority claimed from JP1236156A external-priority patent/JPH0780312B2/ja
Priority claimed from JP24125289A external-priority patent/JPH03102364A/ja
Application filed by Matsushita Electric Industrial Co Ltd filed Critical Matsushita Electric Industrial Co Ltd
Publication of EP0389229A2 publication Critical patent/EP0389229A2/fr
Publication of EP0389229A3 publication Critical patent/EP0389229A3/fr
Withdrawn legal-status Critical Current

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Classifications

    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00—Apparatus for electrographic processes using a charge pattern
    • G03G15/01—Apparatus for electrographic processes using a charge pattern for producing multicoloured copies
    • G03G15/0142—Structure of complete machines
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00—Apparatus for electrographic processes using a charge pattern
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00—Apparatus for electrographic processes using a charge pattern
    • G03G15/01—Apparatus for electrographic processes using a charge pattern for producing multicoloured copies
    • G03G15/0142—Structure of complete machines
    • G03G15/0178—Structure of complete machines using more than one reusable electrographic recording member, e.g. one for every monocolour image
    • G03G15/0194—Structure of complete machines using more than one reusable electrographic recording member, e.g. one for every monocolour image primary transfer to the final recording medium
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00—Apparatus for electrographic processes using a charge pattern
    • G03G15/22—Apparatus for electrographic processes using a charge pattern involving the combination of more than one step according to groups G03G13/02 - G03G13/20
    • G03G15/34—Apparatus for electrographic processes using a charge pattern involving the combination of more than one step according to groups G03G13/02 - G03G13/20 in which the powder image is formed directly on the recording material, e.g. by using a liquid toner
    • G03G15/344—Apparatus for electrographic processes using a charge pattern involving the combination of more than one step according to groups G03G13/02 - G03G13/20 in which the powder image is formed directly on the recording material, e.g. by using a liquid toner by selectively transferring the powder to the recording medium, e.g. by using a LED array
    • G03G15/348—Apparatus for electrographic processes using a charge pattern involving the combination of more than one step according to groups G03G13/02 - G03G13/20 in which the powder image is formed directly on the recording material, e.g. by using a liquid toner by selectively transferring the powder to the recording medium, e.g. by using a LED array using a stylus or a multi-styli array

Definitions

  • the present invention relates to an image forming apparatus such as a copying machine and a printer.
  • An image forming apparatus utilizing an electro­photographic system which is disclosed, for example, in Japanese Patent Unexamined Publication No. 58-214175, is generally known as a conventional one for the copying machine, the printer and other like.
  • the conventional apparatus is constituted by, as shown in Figure 8, a photosensitive drum 101 serving as a latent image bearing medium, a charging unit 102 for estab­lishing a uniform charge in the photosensitive drum 101, an optical system 103 such as a laser and an LED array for forming a latent image on the charged photosensitive drum 101 by applying a beam in accordance with recording signals, a developing unit 104 for making the latent image on the photosensitive drum 101 visible by means of a developer, a unit 105 for transferring the visible image on the photosensitive drum 101, which has been developed by the developing unit 104, to a recording medium 106, a cleaner 107 for removing the developer remaining on the photosensitive drum 101 after the transfer operation and disposing of the waste toner, and a fixing unit 108 for adhering the developer transferred onto the recording medium 106. Therefore, the apparatus has the advantage of higher speed operation and higher resolution owing to separation of function, in addition to the capability of recording to plain paper.
  • An object of the present invention is to provide an image forming apparatus which is made compact by adopting a simple image forming process and which exhibits excellent maintenability and handling efficiency for the user.
  • an image forming apparatus is featured in that in a developer unit in which a developer, a developer carrier and layer forming means are integratedly unified, the developer charged to have a predetermined polarity is uniformly formed into a thin layer on the developer carrier by the layer forming means, a latent image charged to have the reversed polarity is formed on the developer carrier by applying ion onto the charged developer thereon in accordance with recording signals, and the developer only in the portion corresponding to the latent image is directly transferred from the developer carrier to a recording medium.
  • the image forming process is very simplified since formation of latent image, developing and transfer are effected intensively on the developer carrier. This makes it possible to make compact the apparatus while disusing the photosensitive drum and the cleaner which are used in the conventional electrophotographic system.
  • the apparatus can be made very easy to maintain and handle.
  • a developer unit 4 comprises a developer carrier 1, casing containing developer 2 and a layer forming means 3 which are unified.
  • the layer forming means 3 comprises a brush roller 3a, a supply member 3b and a blade 3c.
  • the developer unit 4 is detachably mounted to an image forming apparatus likewise the process cartridge used in the electrophotographic system.
  • Ion irradiation means 5 comprises a generating portion 6 and a controlling portion 7. It is preferable to utilize the aerial discharge such as a corona discharge and a creepage discharge in order to generate ions.
  • Figure 2 shows an example of the ion irradiation means 5 which utilizes the corona discharge.
  • the generating portion 6 is formed by a so-called corona discharge device constructed such that a wire 6b of tungsten or the like extends inside a shield case 6a having a substantially U-shaped cross section.
  • a sheet insulator 7a is provided with through holes 7d through which ions pass in accordance with dots to be recorded and which are arranged in a straight or zigzag manner.
  • the sheet insulation 7 is also provided at one surface thereof with control electrodes 7b associated with the respective through holes 7d and at the other surface thereof with a common control electrode 7c to all the through holes 7d.
  • the apparatus includes means 14 for applying a control voltage between the control electrodes 7b and 7c of the ion controlling portion 7. It is noted that the ion irradiation means 5 may be one which utilizes the creepage discharge as disclosed in Japanese Patent Unexamined Publication No. 57-501348.
  • the apparatus further includes transfer means 8, a recording medium 9, paper feeding means 10 constituted by a paper feeding roller and a cassette, and fixing means 11.
  • the developer 2 is supplied by the layer forming means 3 onto the developer carrier 1 to form a thin layer thereon.
  • the supply member 3b serves to stir the developer 2 in the developer casing and supply it to the brush roller 3a.
  • the brush roller 3a supplies a constant quantity of developer 2 to the developer carrier 1 while holding it in the brush.
  • the developer 2 thus supplied is successively uniformed by the blade 3c into a thin layer on the developer carrier 1 rotating in the direction of an arrow shown in Figure 1.
  • the developer 2 is charged to have an predetermined polarity due to the friction with the layer forming means 3. It is desirable, for assuring the uniform charge, that this thin layer is formed to have a thickness equal to that of a single layer of the developer 2.
  • the ion generating portion 6 of the ion irradiation means 5 generates ions having a polarity opposite to that of the charged developer 2. Irradiation of the ion from the generating portion 6 to the developer 2 is controlled by the ion controlling portion 7 in accordance with the recording signals so that only the developer in a portion corresponding to an image is charged to have the reversed polarity so as to form a charged latent image in order.
  • the portion of the developer 2 on the developer carrier 1 forming the charged latent image is transferred onto the recording medium 9 sent out from the paper feeding means 10 in the direction of an arrow shown in Figure 1 at a transferring position by means of the transfer means 8, such as a corona transfer device, which has a polarity opposite to that of the charged latent image, that is, the same polarity as the charge by the layer forming means 3.
  • the transfer means 8 such as a corona transfer device, which has a polarity opposite to that of the charged latent image, that is, the same polarity as the charge by the layer forming means 3.
  • the recording medium 9 is fed through the fixing means 11 in order to fix a transferred visible image of the developer 2 thereon, thereby completing a recorded image.
  • a part of the developer carrier 1 having passed through the transfer means 8 enters again the developer casing.
  • the developer 2 is charged, and supplied onto and uniformed into a thin layer on the developer carrier 1, including the portion from which the developer has been removed by the transfer operation, by the layer forming means 3, thus preparing for the succeeding recording.
  • the developer 2 used in this embodiment is a one-­component non-magnetic toner with a particle size of about 10 ⁇ m, which is composed of styrene acrylic resin binder, pigment, charge controller such as silica, and the like.
  • the developer carrier 1 used is a conductive metallic roller made of stainless steel, aluminum or the like. It is noted that the developer carrier 1 is provided in the surface thereof with fine concaves formed by means of sand-blasting or the like in order to facilitate the formation of the uniform thin layer of the developer 2.
  • the brush roller 3a of the layer forming means 3 has thin conductive filaments planted around a core, which filament has a specific resistance of 105 to 108 ⁇ cm and is made of rayon containing carbon.
  • the supply member 3b of the means 3 is made of a sheet of polyethylene tere­phthalate or the like.
  • the blade 3c of the means 3 is made of an elastic material such as urethane rubber to press the developer carrier 1 at a line pressure of about 40 g/cm.
  • the developer carrier 1 As the developer carrier 1 is rotated in this state, a uniform thin layer of the developer 2 is formed on the developer carrier 1, the thickness of which is substantially about 30 ⁇ m.
  • the axial surface potential of the developer carrier 1 is about +25 V uniformly and the amount of charge of the developer 2 is about +1.5 ⁇ C/g.
  • the ion generating portion 6 is a corona discharge device in which the tungsten wire 6b ( ⁇ 60 ⁇ m) extends inside the shield case 6a having a substantially U-shaped cross section, as mentioned above.
  • the ion controlling portion 7 includes the sheet insulator 7a having a thickness of 0.4 mm.
  • a plurality of through holes 7d (each having a diameter of 0.4 mm) are formed in the insulator 7a in a gigzag manner, the number of which is in accordance with the recording dots. Ions pass through the holes 7d from the generating portion 6 to the developer carrier 1.
  • the control electrodes 7b and 7c made of copper foil of 20 ⁇ m thickness are disposed opposite surfaces of the insulator 7a.
  • the control electrodes 7b are fixed on one surface of the insulator 7a concentrically with the respective through holes 7d as shown in Figure 2, while the control electrode 7c extends on the other surface thereof common to all the through holes 7d.
  • Irradiation of the ions to the developer 2 on the developer carrier 1 is controlled by applying the voltage to the control electrodes 7b and 7c through the controlling voltage applying means 14. Namely, the developer carrier 1 is grounded, while the control electrode 7c is always applied with a voltage of -200 V. In case of no irradiation of negative ion onto the developer 2 (or when the irradiation of ions is inter­ rupted), the control electrode 7b is held at 0 V and an electric field is applied between the control electrodes 7b and 7c, which is inverse to the electric field between the wire 6b and the developer carrier 1, thereby prevent­ing the negative ions from passing through the hole 7d.
  • the voltage of -300 V is applied to the control electrodes 7b to form an electric field of the same direction as the electric field between the wire 6b and the developer carrier 1, thereby allowing the flow of ions to pass through the hole 7d.
  • the latent image pattern is formed in accordance with the recording signals.
  • the charge of the developer 2 in the portion corresponding to the latent image is changed from positive to negative, the surface potential of the portion of the developer carrier 1 corresponding to the latent image becomes about -70 V, and the amount of charge of the developer 2 becomes about -4.0 ⁇ C/g.
  • a corona charger in used as the transfer means 8.
  • a voltage of +6 kV is applied to a wire of the corona charger 8 to effect the transfer onto the recording medium 9.
  • the recording medium 9 used is the plain paper for copying machine use.
  • thermal fixing device which is used in the copying machine of the electrophoto­graphic system and other like, is used as the fixing means 11 so as to melt and fix the developer 2 on the recording medium 9, thereby forming an image on the recording medium 9 in accordance with the recording signals.
  • the developer 2 In connection with the fog, even when the developer 2 is uniform into a thin layer on the developer carrier 1 and charged apparently to have the predetermined polarity with a surface potential of about +25 V by the layer forming means 3, if the developer 2 is laminated on the developer carrier 1 into multiple layers, for example, two to three layers, the developer 2 is not always charged entirely to have the positive polarity but partly has the negative polarity.
  • the developer 2 thus charged to have the negative polarity even if it is in the portion other than that corresponding to the latent image, is susceptible to be transferred to the recording medium 9 because of its polarity opposite to that of a charge for effecting the transfer, thereby causing the fog.
  • the thin layer of the developer 2 is formed to have a thickness equal to that of a single layer of the developer 2, provided that the density of the recorded image is satisfactory.
  • a corona charger (using a wire of ⁇ 60 ⁇ m) is provided at a position preceding to the ion irradiation means 5 as a first supplemental charging means 12 for the developer 2.
  • a voltage of +4 kV is applied to the charging means 12 to generate and irradiate positive ions to the developer 2 on the developer carrier 1.
  • the surface potential of the developer 2 is about +100 V. Therefore, the ion applying means 5 irradiate the ions to the developer 2 in the same manner as described before so as to form a latent image pattern.
  • a voltage of about +6 kV is applied to the corona transfer device 8 to effect the transfer to the recording medium 9.
  • the developer 2 uniformly charged and formed into a thin layer on the developer carrier 1 by the layer forming means 3 is further charged with use of the charging means 12 in advance of the ion irradiation means 5, and therefore, the reversed polarity on the developer 2 can be canceled, resulting in the prevention of the fog. This contributes to the improve­ment of the picture quality of the recorded image.
  • the developer 2 cannot be supplied sufficiently to the portion on the developer carrier 1 from which the developer 2 has been removed by the transfer operation, thereby causing a little unevenness of the density on the recorded image.
  • the developer 2 is uniformly charged to have the positive polarity and laminated into a thin layer by the layer forming means 3 in the developer unit 4, thus preparing for the succeeding recording.
  • the developer 2 having the negative polarity and remaining slightly on the developer carrier 1 still after having passed through the transfer means 8 enters the developer casing while sticking on the developer carrier 1, it is absorbed electrostatically to the developer 2 having the positive polarity and suffi­ciently sticking on the conductive brush roller 3a, so that the developer 2 cannot be satisfactorily supplied onto and formed into a thin layer on the developer carrier 1.
  • a corona charger (using a wire of ⁇ 60 ⁇ m) is provided as a second supplemental charging means 13 at a position between the transfer means 8 and the developer unit 4 with respect to the direction of rotation of the developer carrier 1.
  • a voltage of +4 kV is applied to the charging means 13 to generate and forcedly irradiate positive ions to the developer 2 on the developer carrier 1.
  • the developer 2 can be kept in the positive polarity and not absorbed by the developer 2 having the positive polarity on the brush roller 3a. Therefore, the developer 2 can be supplied sufficiently to the portion on the developer carrier 1 from which the developer 2 has been removed by the transfer operation without causing any unevenness of the density.
  • the developer 2 having the reversed polarity and remaining on the developer carrier 1 still after the transfer operation is charged forcedly to have the normal polarity that it has by the charging means 13. Therefore, in repeated forming a thin layer of the developer 2 on the developer carrier 1 by the layer forming means 3, the uneven supply of the developer 2, that is, the inequality of the layer thickness on the developer carrier 1, which is attributable to the developer 2 having the reversed polarity, can be eliminated and, hence, the unevenness of the density can be prevented, thereby improving the picture quality of the recorded image.
  • the amount of charge of the developer 2 by the first and second charging means 12 and 13 varies depending upon the amount of ions to be irradiated.
  • it is possible to control the amount of ions to be irradiated by changing the voltage to be supplied to the charging means and the time period during which the power is supplied thereto depending on the recording speed. Such control is conducted in accordance with the surface potential at the state free from the fog and with the state free from unevenness of the density attributable to the uneven supply of the developer.
  • the corona charger is used as first and second charging means 12 and 13, however, it is also possible to use a solid-­state discharge device in which a pair of strip electrodes are formed through a dielectric such as resin layer or ceramics. In the latter case, it is enable to make an apparatus compact and easy to handle.
  • the developer carrier 1 carrying the developer 2 is partially exposed out of the developer casing.
  • the developer 2 on the developer carrier 1 is caused to drop and scatter, resulting in the problem that the apparatus and recorded image are stained.
  • means 15 is provided to apply a bias voltage between the developer carrier 1 and the layer forming means 3, particularly, the brush roller 3a.
  • the developer carrier 1 is made to further rotate without recording operation.
  • a negative voltage (ranging from -50 to -100 V preferably) is applied between the developer carrier 1 and the brush roller 3a by the bias voltage applying means 15, so that the developer 2 having the positive polarity on the developer carrier 1 is attracted into the developer unit 4 by the brush roller 3a, thereby removing almost all of the developer 2 from the developer carrier 1.
  • the developer carrier 1 and the brush roller 3a are made to have the same potential, namely a switch of the bias voltage applying means 15 is turned as shown in Fig. 6.
  • the developer carrier 1 is rotated in advance of the start of the recording, and then the developer 2 can be supplied sufficiently onto the developer carrier 1 and formed into a thin layer thereon.
  • Removal of the developer 2 from the developer carrier 1 is made by applying a voltage between the developer carrier 1 and the brush roller 3a, and there­fore, it is possible to prevent the developer 2 from dropping and scattering from the developer carrier 1 even if it is subjected to an excessive vibration or impact when the apparatus is standing by or out of use. This contributes to the prevention of the stain of the apparatus and the recorded image and hence to the improvement of the reliability of the apparatus.
  • the process can be simplified and the apparatus can be made compact and thin while disusing the photosensitive drum and the cleaner which are used in the conventional electrophotographic system.
  • the movable portion is only the developer carrier 1, it is possible to improve the stillness and the reliability of the apparatus as a whole.
  • the provisions of the first and second charging means 12 and 13, and the bias voltage applying means 15 assure the prevention of the fog, unevenness of the density, and drop and scatter of the developer.
  • Reference numerals 30Y, 30M and 30C denote developer carriers for yellow, magenta, and cyan, respec­tively; numerals 40Y, 40M and 40C denote developer units for yellow, magenta, and cyan, respectively; numerals 50Y, 50M and 50C denote latent image forming means for yellow, magenta, and cyan, respectively; and numerals 60Y, 60M and 60C denote transfer means for yellow, magenta, and cyan, respectively.
  • An image forming process using a black developer may be provided before the yellow process or after the cyan process.
  • the respective color developer which form the respective latent images and reversely charged by irradiation of ions are transferred in order onto the recording medium 9 sent out from the paper feeding means 10 in superimposition manner at the positions correspond­ing to the respective transfer means 60. Then, after passing through the fixing means 11, a color recorded image is obtained.
  • first and second charging means may be provided around the respective developer carriers in order to prevent the recorded image from suffering the fog and the density unevenness
  • bias voltage applying means may be provided between the developer carrier and the layer forming means, which is not shown, in order to prevent the drop and scatter of the developer.
  • the developer in the developer unit may be either of one-­ component and two-component toners so far as the developer is uniformly charged and laminated into a thin layer on the developer carrier at least after passing through the blade.
  • the brush roller and the blade of the layer forming means may be a roller of an elastic material such as sponge and a rigid blade which is in or out of contact with the developer carrier, respectively.
  • the polarity of the first and second charging means and is the same as that of the developer charged in the developer unit in the embodiment, the polarity of the may be either positive or negative so far as the polarity of the developer in the portion corresponding to the portion other than the latent image and the polarity of the developer in the portion corresponding to the latent image charged by the ion irradiation means are differed from each other clearly.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Electrophotography Using Other Than Carlson'S Method (AREA)
  • Electrostatic Charge, Transfer And Separation In Electrography (AREA)
  • Printers Or Recording Devices Using Electromagnetic And Radiation Means (AREA)
EP19900302946 1989-03-22 1990-03-19 Appareil de formation d'images Withdrawn EP0389229A3 (fr)

Applications Claiming Priority (8)

Application Number Priority Date Filing Date Title
JP69665/89 1989-03-22
JP1069665A JPH02248969A (ja) 1989-03-22 1989-03-22 画像形成装置
JP1095749A JPH0789252B2 (ja) 1989-04-14 1989-04-14 画像形成装置
JP95749/89 1989-04-14
JP236156/89 1989-09-12
JP1236156A JPH0780312B2 (ja) 1989-09-12 1989-09-12 画像形成装置
JP241252/89 1989-09-18
JP24125289A JPH03102364A (ja) 1989-09-18 1989-09-18 画像形成装置

Publications (2)

Publication Number Publication Date
EP0389229A2 true EP0389229A2 (fr) 1990-09-26
EP0389229A3 EP0389229A3 (fr) 1991-05-02

Family

ID=27465163

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19900302946 Withdrawn EP0389229A3 (fr) 1989-03-22 1990-03-19 Appareil de formation d'images

Country Status (2)

Country Link
EP (1) EP0389229A3 (fr)
KR (1) KR900014945A (fr)

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1997034205A1 (fr) * 1996-03-12 1997-09-18 Ito Engineering Ab Dispositif d'impression a jet de toner comportant une matrice balayee electriquement
WO1997034203A1 (fr) * 1996-03-12 1997-09-18 Ito Engineering Ab Dispositif d'impression du type a jet de toner
WO1997034204A1 (fr) * 1996-03-12 1997-09-18 Ito Engineering Ab Dispositif d'impression du type a jet de toner comportant une matrice redressee
US5971526A (en) * 1996-04-19 1999-10-26 Array Printers Ab Method and apparatus for reducing cross coupling and dot deflection in an image recording apparatus
US6000786A (en) * 1995-09-19 1999-12-14 Array Printers Publ. Ab Method and apparatus for using dual print zones to enhance print quality
US6011944A (en) * 1996-12-05 2000-01-04 Array Printers Ab Printhead structure for improved dot size control in direct electrostatic image recording devices
US6012801A (en) * 1997-02-18 2000-01-11 Array Printers Ab Direct printing method with improved control function
US6017116A (en) * 1994-09-19 2000-01-25 Array Printers Ab Method and device for feeding toner particles in a printer unit
US6030070A (en) * 1997-12-19 2000-02-29 Array Printers Ab Direct electrostatic printing method and apparatus
US6062676A (en) * 1994-12-15 2000-05-16 Array Printers Ab Serial printing system with direct deposition of powder particles
US6074045A (en) * 1998-03-04 2000-06-13 Array Printers Ab Printhead structure in an image recording device
US6081283A (en) * 1998-03-19 2000-06-27 Array Printers Ab Direct electrostatic printing method and apparatus
US6086186A (en) * 1997-12-19 2000-07-11 Array Printers Ab Apparatus for positioning a control electrode array in a direct electrostatic printing device
US6102525A (en) * 1998-03-19 2000-08-15 Array Printers Ab Method and apparatus for controlling the print image density in a direct electrostatic printing apparatus
US6109730A (en) * 1997-03-10 2000-08-29 Array Printers Ab Publ. Direct printing method with improved control function
US6174048B1 (en) 1998-03-06 2001-01-16 Array Printers Ab Direct electrostatic printing method and apparatus with apparent enhanced print resolution
US6257708B1 (en) 1997-12-19 2001-07-10 Array Printers Ab Direct electrostatic printing apparatus and method for controlling dot position using deflection electrodes
US6361148B1 (en) 1998-06-15 2002-03-26 Array Printers Ab Direct electrostatic printing method and apparatus
US6361147B1 (en) 1998-06-15 2002-03-26 Array Printers Ab Direct electrostatic printing method and apparatus

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3143968A1 (de) * 1980-11-05 1982-06-09 Konishiroku Photo Industry Co., Ltd., Tokyo Elektrostatisches vervielfaeltigungsgeraet
US4544935A (en) * 1981-06-11 1985-10-01 Ricoh Company, Ltd. Recording apparatus
JPH06125166A (ja) * 1992-10-12 1994-05-06 Sony Corp 回路基板
JPH06165270A (ja) * 1992-11-27 1994-06-10 Matsushita Electric Ind Co Ltd プログラムリモコン送信機

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3143968A1 (de) * 1980-11-05 1982-06-09 Konishiroku Photo Industry Co., Ltd., Tokyo Elektrostatisches vervielfaeltigungsgeraet
US4544935A (en) * 1981-06-11 1985-10-01 Ricoh Company, Ltd. Recording apparatus
JPH06125166A (ja) * 1992-10-12 1994-05-06 Sony Corp 回路基板
JPH06165270A (ja) * 1992-11-27 1994-06-10 Matsushita Electric Ind Co Ltd プログラムリモコン送信機

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 10, no. 177 (P-470)(2233), 21 June 1986; & JP - A - 6125166 (FUJI XEROX CO. LTD.) 04.02.1986 *
PATENT ABSTRACTS OF JAPAN vol. 10, no. 232 (P-486)(2288), 12 August 1986; & JP - A - 6165270 (FUJI XEROX CO. LTD.) 03.04.1986 *

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6017116A (en) * 1994-09-19 2000-01-25 Array Printers Ab Method and device for feeding toner particles in a printer unit
US6062676A (en) * 1994-12-15 2000-05-16 Array Printers Ab Serial printing system with direct deposition of powder particles
US6000786A (en) * 1995-09-19 1999-12-14 Array Printers Publ. Ab Method and apparatus for using dual print zones to enhance print quality
WO1997034203A1 (fr) * 1996-03-12 1997-09-18 Ito Engineering Ab Dispositif d'impression du type a jet de toner
WO1997034204A1 (fr) * 1996-03-12 1997-09-18 Ito Engineering Ab Dispositif d'impression du type a jet de toner comportant une matrice redressee
WO1997034205A1 (fr) * 1996-03-12 1997-09-18 Ito Engineering Ab Dispositif d'impression a jet de toner comportant une matrice balayee electriquement
US5971526A (en) * 1996-04-19 1999-10-26 Array Printers Ab Method and apparatus for reducing cross coupling and dot deflection in an image recording apparatus
US6011944A (en) * 1996-12-05 2000-01-04 Array Printers Ab Printhead structure for improved dot size control in direct electrostatic image recording devices
US6012801A (en) * 1997-02-18 2000-01-11 Array Printers Ab Direct printing method with improved control function
US6109730A (en) * 1997-03-10 2000-08-29 Array Printers Ab Publ. Direct printing method with improved control function
US6030070A (en) * 1997-12-19 2000-02-29 Array Printers Ab Direct electrostatic printing method and apparatus
US6086186A (en) * 1997-12-19 2000-07-11 Array Printers Ab Apparatus for positioning a control electrode array in a direct electrostatic printing device
US6257708B1 (en) 1997-12-19 2001-07-10 Array Printers Ab Direct electrostatic printing apparatus and method for controlling dot position using deflection electrodes
US6074045A (en) * 1998-03-04 2000-06-13 Array Printers Ab Printhead structure in an image recording device
US6174048B1 (en) 1998-03-06 2001-01-16 Array Printers Ab Direct electrostatic printing method and apparatus with apparent enhanced print resolution
US6081283A (en) * 1998-03-19 2000-06-27 Array Printers Ab Direct electrostatic printing method and apparatus
US6102525A (en) * 1998-03-19 2000-08-15 Array Printers Ab Method and apparatus for controlling the print image density in a direct electrostatic printing apparatus
US6361148B1 (en) 1998-06-15 2002-03-26 Array Printers Ab Direct electrostatic printing method and apparatus
US6361147B1 (en) 1998-06-15 2002-03-26 Array Printers Ab Direct electrostatic printing method and apparatus

Also Published As

Publication number Publication date
EP0389229A3 (fr) 1991-05-02
KR900014945A (ko) 1990-10-25

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