EP0833220A1 - System zur Farbenmischung und Steuerung für ein elektrostatographisches Druckgerät - Google Patents

System zur Farbenmischung und Steuerung für ein elektrostatographisches Druckgerät Download PDF

Info

Publication number
EP0833220A1
EP0833220A1 EP97307326A EP97307326A EP0833220A1 EP 0833220 A1 EP0833220 A1 EP 0833220A1 EP 97307326 A EP97307326 A EP 97307326A EP 97307326 A EP97307326 A EP 97307326A EP 0833220 A1 EP0833220 A1 EP 0833220A1
Authority
EP
European Patent Office
Prior art keywords
developing material
color
supply
developing
reservoir
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.)
Granted
Application number
EP97307326A
Other languages
English (en)
French (fr)
Other versions
EP0833220B1 (de
Inventor
Edward B. Caruthers, Jr.
Enrique R. Viturro
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.)
Xerox Corp
Original Assignee
Xerox Corp
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
Application filed by Xerox Corp filed Critical Xerox Corp
Publication of EP0833220A1 publication Critical patent/EP0833220A1/de
Application granted granted Critical
Publication of EP0833220B1 publication Critical patent/EP0833220B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

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
    • G03G15/0105—Details of unit
    • G03G15/0121—Details of unit for developing
    • 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
    • G03G15/06—Apparatus for electrographic processes using a charge pattern for developing
    • G03G15/08—Apparatus for electrographic processes using a charge pattern for developing using a solid developer, e.g. powder developer
    • G03G15/0822—Arrangements for preparing, mixing, supplying or dispensing developer
    • G03G15/0848—Arrangements for testing or measuring developer properties or quality, e.g. charge, size, flowability
    • G03G15/0849—Detection or control means for the developer concentration
    • G03G15/0855—Detection or control means for the developer concentration the concentration being measured by optical means
    • 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
    • G03G15/06—Apparatus for electrographic processes using a charge pattern for developing
    • G03G15/08—Apparatus for electrographic processes using a charge pattern for developing using a solid developer, e.g. powder developer
    • G03G15/0822—Arrangements for preparing, mixing, supplying or dispensing developer
    • G03G15/0877—Arrangements for metering and dispensing developer from a developer cartridge into the development unit
    • G03G15/0879—Arrangements for metering and dispensing developer from a developer cartridge into the development unit for dispensing developer from a developer cartridge not directly attached to the development unit
    • 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
    • G03G15/06—Apparatus for electrographic processes using a charge pattern for developing
    • G03G15/10—Apparatus for electrographic processes using a charge pattern for developing using a liquid developer
    • G03G15/104—Preparing, mixing, transporting or dispensing developer
    • G03G15/105—Detection or control means for the toner concentration
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G2215/00—Apparatus for electrophotographic processes
    • G03G2215/00025—Machine control, e.g. regulating different parts of the machine
    • G03G2215/00118—Machine control, e.g. regulating different parts of the machine using fuzzy logic

Definitions

  • This invention relates generally to a development system for creating color output images in an electrostatographic printing machine and, more particularly, concerns a system for providing customized color control in a liquid developing material-based electrostatographic printing system.
  • the color mixing and control system operates by sensing the color of an operational mixture of developing material comprised of a blend of multiple basic color components and to further control the concentration of respective basic color components used to replenish the operational mixture.
  • the charged photoconductive member may be sequentially exposed to a series of color separated images corresponding to the primary colors in an input image in order to form a plurality of color separated latent images.
  • Each color separated image is developed with a complimentary developing material containing a primary color or a colorant which is the subtractive compliment of the color separated image, with each developed color separated image subsequently superimposed, in registration, on one another to produce a multicolor image output.
  • a multicolor image is generated from patterns of different primary colors or their subtractive compliments which are blended by the eye to create a visual perception of a color image.
  • customer selectable color printing wherein a very specific highlight color is required.
  • Customer selectable colors are typically utilized to provide instant identification and authenticity to a document. As such, the customer is usually highly concerned that the color meets particular color specifications. For example, the red color associated with Xerox' digital stylized "X" is a customer selectable color having a particular shade, hue and color value. Likewise, the particular shade of orange associated with Syracuse University is a good example of a customer selectable color.
  • a more specialized example of a customer selectable color output can be found in the field of "custom color", which specifically refers to registered proprietary colors, as used, for example, in corporate logos, authorized letterhead and official seals.
  • custom color specifically refers to registered proprietary colors, as used, for example, in corporate logos, authorized letterhead and official seals.
  • the yellow associated with Kodak brand products, and the brown associated with Hershey brand products are good examples of custom colors which are required to meet exacting color standards in a highlight color or spot color printing application.
  • customer selectable color production in electrostatographic printing systems is typically carried out by providing a singular premixed developing material composition made up of a mixture of multiple color toner particles blended in preselected concentrations for producing the desired customer selectable color output.
  • This method of mixing multiple color toners to produce a particular color developing material is analogous to processes used to produce customer selectable color paints and inks.
  • offset printing for example, a customer selectable color output image is produced by printing a solid image pattern with a premixed customer selectable color printing ink as opposed to printing a plurality of halftone image patterns with various primary colors or compliments thereof.
  • This concept has generally been extended to electrostatographic printing technology, as disclosed, for example, in commonly assigned U.S. Patent No. 5,557,393, wherein an electrostatic latent image is developed by a dry powder developing material comprising two or more compatible toner compositions to produce a customer selectable color output.
  • Customer selectable color printing materials including paints, printing inks and developing materials can be manufactured by determining precise amounts of constituent basic color components making up a given customer selectable color material, providing precisely measured amounts of each constituent basic color component, and thoroughly mixing these color components. This process is commonly facilitated by reference to a color guide or swatch book containing hundreds or even thousands of swatches illustrating different colors, wherein each color swatch is associated with a specific formulation of colorants. Probably the most popular of these color guides is published by Pantone®, Inc. of Moonachie, New Jersey.
  • the Pantone® Color Formula Guide expresses colors using a certified matching system and provides the precise formulation necessary to produce a specific customer selectable color by physically intermixing predetermined concentrations of up to four colors from a set of up to 18 principal or basic colors. There are many colors available using the Pantone® system or other color formula guides of this nature that cannot be produced via typical halftone process color methods or even by mixing selected amounts of cyan, magenta, yellow and/or black inks or developing materials.
  • the present invention contemplates a development system including a color mixing and control system, wherein the color value of the developing material in a supply reservoir can be controlled and the rate of replenishment of various color components added to the supply reservoir can be selectively varied.
  • the color value of the developing material in a supply reservoir can be controlled and the rate of replenishment of various color components added to the supply reservoir can be selectively varied.
  • a system for providing a customer selectable color developing material in an electrostatographic printing machine comprises: a plurality of developing material supply receptacles, each containing a differently colored developing material concentrate corresponding to a basic color component of a color matching system; a developing material reservoir, having at least one of the plurality of developing material supply receptacles coupled thereto, for providing a supply of operative developing material having the specified color; and a system for systematically dispensing a selected amount of developing material concentrate from at least a selected one of the developing material supply receptacles to the developing material reservoir to provide a selected basic color component to the supply of operative developing material.
  • an apparatus for developing an electrostatic latent image with a developing material having a specified color value comprises: a plurality of developing material supply dispensers, each containing a differently colored developing material concentrate corresponding to a basic color component of a color matching system; a developing material reservoir, for providing an operative supply of developing material having the specified color value.
  • an electrostatographic printing process wherein at least a portion of an electrostatic latent image is developed with a developing material having a specified color value.
  • the process comprises the steps of: providing a plurality of differently colored developing concentrate materials corresponding to a plurality of basic color components of a color matching system; selectively delivering at least one of the plurality of differently colored developing concentrate materials to a developing material reservoir for producing an operative supply of developing material having the specified color value; and systematically dispensing a selected amount of developing material concentrate of a selected basic color component to the developing material reservoir for providing a selected basic color component to the operative supply of developing material.
  • control system may also be utilized to mix a customer selectable color in situ, whereby approximate amounts of primary or basic color components are initially deposited and mixed in the developing material reservoir, with this developing material mixture being continually monitored and adjusted until the mixture meets some predetermined target optical properties.
  • FIG. 1 provides a schematic, elevational view of an exemplary liquid developing material applicator and an exemplary liquid developing material development system incorporating a liquid developing material color mixing and control system in accordance with the present invention. While the present invention will be described with respect to a liquid developing apparatus, it will be understood that the mixing and control system of the present invention is not limited to liquid developing materials and may be utilized in dry powder electrostatographic applications as well as liquid electrostatographic applications.
  • the color mixing and control system of the present invention may be equally well-suited for use in a wide variety of printing machines and is not necessarily limited in its application to any particular single-pass highlight tri-level electrostatographic process.
  • the color mixing and control system of the present invention may be extended to any electrostatographic printing process intended to produce a customer selectable color image area including multi-color printing machines which may be provided with an ancillary customer selectable color development housing, as well as printing machines which carry out ionographic printing processes and the like.
  • FIG. 1 an exemplary apparatus for developing an electrostatic latent image, wherein liquid developing materials are utilized is depicted in schematic form.
  • a highlight color electrostatographic printing machine would include at least two developing apparatus operating with different color liquid developing materials for developing latent image areas into different colored visible images.
  • a first developer apparatus might be utilized to develop the positively charged image area with black colored liquid developing material, while a second developer apparatus might be used to develop the negatively charged image area image with a customized color.
  • each different color developing material comprises pigmented toner or marking particles, as well as charge control additives and charge directors, all disseminated through a liquid carrier, wherein the marking particles are charged to a polarity opposite in polarity to the charged latent image to be developed.
  • the developing apparatus of Fig. 1 operates primarily to transport liquid developer material into contact with a latent image on a photoreceptor surface, generally identified by reference numeral 100, wherein the marking particles are attracted, via electrophoresis, to the electrostatic latent image for creating a visible developed image thereof.
  • the basic manner of operation of each developer apparatus is generally identical to one another and the developing apparatus shown in FIG. 1 represents only one of various known apparatus that can be utilized to apply liquid developing material to the photoconductive surface.
  • the basic development system incorporating the mixing and control system of the present invention may be directed to either liquid or dry powder development and may take many forms, as for example, systems described in U.S.
  • Patents 3,357,402; 3,618,552; 4,733,273; 4,883,018; 5,270,782 and 5,355,201 may be utilized in a multicolor electrophotographic printing machine, a highlight color machine, or in a monochromatic printing machine.
  • liquid developing material is transported from an supply reservoir 10 to the latent image on the photoreceptor 100 via a liquid developing material applicator 20.
  • Supply reservoir 10 acts as a holding receptacle for providing an operative solution of liquid developing material comprised of liquid carrier, a charge director compound, and toner material, which, in the case of the customer selectable color application of the present invention, includes a blend of different colored marking particles.
  • a plurality of replaceable supply dispensers 15A - 15Z each containing a concentrated supply of marking particles and carrier liquid corresponding to a basic color component in a color matching system, are provided in association with the operational supply reservoir 10 and coupled thereto for replenishing the liquid developing material therein, as will be described.
  • the exemplary developing material applicator 20 includes a housing 22, having an elongated aperture 24 extending along a longitudinal axis thereof so as to be oriented substantially transverse to the surface of photoreceptor 100, along the direction of travel thereof, as indicated by arrow 102.
  • the aperture 24 is coupled to an inlet port 26 which is further coupled to reservoir 10 via transport conduit 18.
  • Transport conduit 18 operates in conjunction with aperture 24 to provide a path of travel for liquid developing material being transported from reservoir 10 and also defines a developing material application region in which the liquid developing material can freely flow in order to contact the surface of the photoreceptor belt 100 for developing the latent image thereon.
  • liquid developing material is pumped or otherwise transported from the supply reservoir 10 to the applicator 20 through at least one inlet port 26, such that the liquid developing material flows out of the elongated aperture 24 and into contact with the surface of photoreceptor belt 100.
  • An overflow drainage channel (not shown), partially surrounds the aperture 24, may also be provided for collecting excess developing material which may not be transferred over to the photoreceptor surface during development.
  • Such an overflow channel would be connected to an outlet channel 28 for removal of excess or extraneous liquid developing material and, preferably, for directing this excess material back to reservoir 10 or to a waste sump whereat the liquid developing material can preferably be collected and the individual components thereof can be recycled for subsequent use.
  • an electrically biased developer roller 30 Slightly downstream of and adjacent to the developing material applicator 20, in the direction of movement of the photoreceptor surface 100, is an electrically biased developer roller 30, the peripheral surface thereof being situated in close proximity to the surface of the photoreceptor 100.
  • the developer roller 30 rotates in a direction opposite the movement of the photoconductor surface 100 so as to apply a substantial shear force to the thin layer of liquid developing material present in the area of the nip between the developer roller 30 and the photoreceptor 100, for minimizing the thickness of the liquid developing material on the surface thereof.
  • This shear force removes a predetermined amount of excess liquid developing material from the surface of the photoreceptor and transports this excess developing material in the direction of the developing material applicator 20.
  • a DC power supply 35 is also provided for maintaining an electrical bias on the metering roll 30 at a selected polarity and magnitude such that image areas of the electrostatic latent image on the photoconductive surface will attract marking particles from the developing material for developing the electrostatic latent image. This electrophoretic development process minimizes the existence of marking particles in background regions and maximizes the deposit of marking particles in image areas on the photoreceptor.
  • liquid developing material is transported in the direction of the photoreceptor 100, filling the gap between the surface of the photoreceptor and the liquid developing material applicator 20.
  • the belt 100 moves in the direction of arrow 102, a portion of the liquid developing material in contact with the photoreceptor moves therewith toward the developing roll 30 where marking particles in the liquid developer material are attracted to the electrostatic latent image areas on the photoreceptor.
  • the developing roller 30 also meters a predetermined amount of liquid developing material adhering to the photoconductive surface of belt 100 and acts as a seal for preventing extraneous liquid developing material from being carried away by the photoreceptor.
  • marking particles are depleted in the image areas; carrier liquid is depleted in the image areas (trapped by marking particles) and in background areas, and may also be depleted by evaporation; and charge director is depleted in the image areas (trapped in the carrier liquid), in the image areas adsorbed onto marking particles, and in the background areas.
  • reservoir 10 is continuously replenished, as necessary, by the addition of developing material or selective components thereof, for example in the case of liquid developing materials, by the addition of liquid carrier, marking particles, and/or charge director into the supply reservoir 10.
  • the total amount of any one component making up the developing material utilized to develop the image may vary as a function of the area of the developed image areas and the background portions of the latent image on the photoconductive surface, the specific amount of each component of the liquid developing material which must be added to the supply reservoir 10 varies with each development cycle. For example, a developed image having a large proportion of printed image area will cause a greater depletion of marking particles and/or charge director from a developing material reservoir as compared to a developed image with a small amount of printed image area.
  • the rate of the replenishment of the liquid carrier component of the liquid developing material may be controlled by simply monitoring the level of liquid developer in the supply reservoir 10, the rate of replenishment of the marking particles, and/or the charge director components of the liquid developing material in reservoir 10 must be controlled in a more sophisticated manner to maintain the correct predetermined concentration for proper functionality of the marking particles and the charge director in the operative solution stored in the supply reservoir 10 (although the concentration may vary with time due to changes in operational parameters).
  • Systems have been disclosed in the patent literature and otherwise for systematically replenishing individual components making up the liquid developing material (liquid carrier, marking particles and/or charge director) as they are depleted from the reservoir 10 during the development process. See, for example, commonly assigned U.S. Patent Application Serial No. 08/551,381 and the references cited therein.
  • the replenishment system of the present invention includes a plurality of differently colored concentrate supply dispensers 15A, 15B, 15C, ... 15Z, at least a pair of which are coupled to the operative supply reservoir via an associated valve member 16A, 16B 16C, ... 16Z, or other appropriate supply control device.
  • each supply dispenser contains a developing material concentrate of a known basic or primary color component used in a given color matching system.
  • each of the plurality of supply dispensers 15A - 15Z may be coupled to the reservoir, or only selected supply dispensers may be coupled to the reservoir 10. For example, under certain circumstances, such as space constraints or cost restraints, it may be desirable to use only dispensers 15A, 15B and 15C, making up a simplified color matching system.
  • the replenishment system includes sixteen supply dispensers, wherein each supply dispenser provides a different basic color developing material corresponding to the sixteen basic or constituent colors of the Pantone® Color Matching System such that color formulations conveniently provided thereby can be utilized to produce over a thousand desirable colors and shades in a customer selectable color printing environment.
  • each supply dispenser provides a different basic color developing material corresponding to the sixteen basic or constituent colors of the Pantone® Color Matching System such that color formulations conveniently provided thereby can be utilized to produce over a thousand desirable colors and shades in a customer selectable color printing environment.
  • supply containers 15A and 15B for example, can be combined in reservoir 10 to expand the color gamut of customer selectable colors far beyond the colors available via halftone imaging techniques or even the colors available from mixing just Yellow, Magenta, Cyan and Black colored developing materials.
  • An essential component of the developing material color mixing and control of the present invention is a mixing control system. That is, since different components of the blended or mixed developing material in reservoir 10 may develop at different rates, a customer selectable color mixing controller 42 is provided in order to determine appropriate amounts of each color developing material in supply containers 15A, 15B ... or 15Z which may need to be added to supply reservoir 10, and to controllably supply each of such appropriate amounts of developing material. Controller 42 may take the form of any known microprocessor based memory and processing device as are well known in the art.
  • the approach provided by the color mixing control system of the present invention includes a sensing device 40, for example an optical sensor for monitoring the color of the liquid developing material in the reservoir 10.
  • a sensing device 40 for example an optical sensor for monitoring the color of the liquid developing material in the reservoir 10.
  • sensor 40 can take various forms and could be of many types as are well known in the art
  • the preferred embodiment of the present invention includes a filter series for sensing the color of the developing material delivered out of the developing material reservoir 10 to the developing material applicator 20.
  • the filter series contemplated by the present invention is represented diagramatically in FIG. 1 as sensing device 40, situated so as to sense the liquid developing material being transported from the liquid developing material reservoir 10 to the developing material applicator 20.
  • various multi-wavelength filter devices may be utilized to detect the color of the developing material including devices which are submerged in the liquid developing material reservoir 10, or devices which monitor the light attenuation across the entire volume of the reservoir 10.
  • Sensor 40 is connected to controller 42 for controlling the flow of the variously colored replenishing liquid developing materials from dispensers 15A - 15Z, corresponding to the basic constituent colors of a color matching system, to be delivered into the liquid developing material supply reservoir 10 from each of the supply containers 15A - 15Z.
  • the controller 42 is coupled to control valves 16A - 16Z for selective actuation thereof to control the flow of liquid developing material from each supply container 15A - 15Z. It will be understood that these valves may be replaced by pump devices or any other suitable flow control mechanisms as known in the art, so as to be substituted thereby.
  • sensor 40 includes a filter series.
  • sensor 40 includes a suitable lamp, filters and a photodetector, wherein light is transmitted from the lamp through the filters and onto the developing material. The reflectance, transmission, or emission of the developing material as it is illuminated, in turn by the light passing through each filter.
  • a predetermined number of relatively narrow bandwidth filters having transmittance peaks distributed across the visible spectrum are utilized to determine the spectral distribution of a test sample, in this case, the developing material being sensed.
  • discernible spectral power distribution can be provided by the filter series so as to distinguish basic color components making up the developing material so as to define the color thereof.
  • the spectral distribution information can also be used to define the color of the developing materials in terms of a particular color coordinate system, such as, for example, the well recognized standardized color notation system for defining uniform color spaces developed by the Commission Internationale de l'Eclairage (CIE).
  • CIE Commission Internationale de l'Eclairage
  • the CIE color specification system employs so called "tristimulus values" to specify colors and to establish device independent color spaces.
  • the CIE standards are widely accepted because measured colors can be readily expressed in the CIE recommended coordinate systems through the use of relatively straight-forward mathematical transformations.
  • the color of the measured sample is compared to the known values corresponding to the desired output color (as may be provided by the color matching system) to determine the precise color formulation necessary in the supply of operative developing material to yield a correct color match.
  • This information is processed by controller 42 for selectively actuating valves 16A - 16Z to systematically dispense to the reservoir 10 selective amounts of developing material concentrate corresponding to selected basic color components from selected supply dispensers 15A - 15Z.
  • sensor 40 is provided in the form of a series of filter elements in combination with a light source and light detector for providing measurements that can be utilized to provide color mixing control. Measurements obtained from the filter series are compared to a priori knowledge of like optical properties of the basic color components making up the customer selectable color developing material to provide an estimate of the concentration levels of each color component in the reservoir as well as the correction necessary to obtain target concentration levels yielding the desired customer selectable color output.
  • the filter series provides a measurement of selected optical properties of the blended developing material in the reservoir 10, wherein this optical property information is subsequently transmitted to the controller 42, which compares the measured optical property information to corresponding known optical property values of the desired output color, as may be stored in a look up table or the like of a memory device. This information is used to determine the appropriate amounts of each color component which should be added to the reservoir 10 via actuation of valves 16A - 16Z, respectively.
  • the A ni are related in principle to the absorption spectra of the developing material components and to the transmission spectra of the filters. However, the A ni can be most usefully obtained by fitting the filter signals from a known set of mixed developing materials. The accuracy of the w i can be improved by using knowledge of which components are added to the mixed developing material.
  • a set of filters is used which is equal to the total number of primaries or basic color components from which all customer selectable colors will be mixed.
  • the transmission of light through each component and each filter is measured and the resulting matrix is inverted to obtain A ni .
  • a set of filters is used which need not be equal to the total number of primaries from which all customer selectable colors will be mixed. Filter responses of a large set of mixed toners are measured and A ni is obtained by minimizing the RMS error between known and estimated concentrations, w ik , for the ith component of the kth mixture.
  • a set of filter responses and a set of known concentrations for a large set of mixed toners is used to train a neural net.
  • a set of filters is used which need not be equal to the total number of primaries or basic color components from which all customer selectable colors will be mixed.
  • filter responses of a large set of mixed developing materials are measured.
  • Different sets of A ni are obtained for different combinations of primary components. For example, a set of A ni is obtained for each unique combination of primary developing materials, such as Yellow and Red; Yellow and Blue; Blue and Red; Yellow, Blue and Red; etc.
  • each set of A ni is obtained by minimizing the RMS error between known and estimated concentrations, w ik , for the ith component of the kth mixture in the set.
  • the first set of six filters above was used to empirically adjust the A ni , resulting in a reduction of the RMS error to approximately 0.067 wt%.
  • an empirical adjustment of the A ni corresponding to the second filter set reduced the RMS error to 0.040 wt%, thus providing much more accurate color control than the first method.
  • test set of 70 mixtures was broken into subsets, each made of 2-3 primary developing materials.
  • first filter set was utilized and a set of A ni was empirically optimized, where i relates only to the primaries used in the mixture subset.
  • empirical optimization of the 2x6 A ni matrix reduced the RMS error to 0.001 wt%.
  • empirical optimization of the 2x6 A ni matrix reduced the RMS error to 0.001 wt%.
  • the present invention provides a system and method for color mixing control in an electrostatographic printing system.
  • a developing reservoir containing an operative solution of customer selectable colored developing material is continuously replenished with the color thereof being controlled and maintained by selectively varying the rate of replenishment of various color components added to the supply reservoir.
  • a series of filter elements is used to measure the optical properties of the developing material in the supply reservoir so that the corresponding optical properties thereof can be brought into agreement with corresponding target optical properties.
  • the present invention can be used to control and maintain the color of the developing material in the reservoir through continuous monitoring and correction thereof in order to maintain a particular ratio of color components in the reservoir over extended periods associated with very long print runs.
  • the present invention may also be utilized to mix a customer selectable color in situ, whereby approximate amounts of primary color components are initially deposited and mixed in the developing material reservoir, this developing material mixture being continually monitored and adjusted until the mixture reaches a some predetermined target optical properties.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Color Electrophotography (AREA)
  • Wet Developing In Electrophotography (AREA)
EP19970307326 1996-09-26 1997-09-19 System zur Farbenmischung und Steuerung für ein elektrostatographisches Druckgerät Expired - Lifetime EP0833220B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US72142196A 1996-09-26 1996-09-26
US721421 1996-09-26

Publications (2)

Publication Number Publication Date
EP0833220A1 true EP0833220A1 (de) 1998-04-01
EP0833220B1 EP0833220B1 (de) 2003-11-26

Family

ID=24897926

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19970307326 Expired - Lifetime EP0833220B1 (de) 1996-09-26 1997-09-19 System zur Farbenmischung und Steuerung für ein elektrostatographisches Druckgerät

Country Status (3)

Country Link
EP (1) EP0833220B1 (de)
JP (1) JPH10104953A (de)
DE (1) DE69726376T2 (de)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0964310A2 (de) * 1998-06-08 1999-12-15 Xerox Corporation System zur Farbenmischung und Steuerung für ein Druckgerät
US7480070B2 (en) 2001-11-20 2009-01-20 Electronics For Imaging, Inc. Spot color pattern system

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2724776A1 (de) * 1976-06-02 1977-12-15 Canon Kk Verfahren und entwickler zum entwickeln elektrischer ladungsbilder
US4111151A (en) * 1977-05-19 1978-09-05 Xerox Corporation Multi-particle developability regulating system
US4113371A (en) * 1977-01-12 1978-09-12 Xerox Corporation Color development system
US5557393A (en) * 1994-11-04 1996-09-17 Xerox Corporation Process and apparatus for achieving customer selectable colors in an electrostatographic imaging system
JPH08248719A (ja) * 1995-03-14 1996-09-27 Ricoh Co Ltd 画像形成方法、並びに該方法に用いるトナー及び副剤パッケージ
JPH08248727A (ja) * 1995-03-14 1996-09-27 Ricoh Co Ltd 画像形成装置

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2724776A1 (de) * 1976-06-02 1977-12-15 Canon Kk Verfahren und entwickler zum entwickeln elektrischer ladungsbilder
US4113371A (en) * 1977-01-12 1978-09-12 Xerox Corporation Color development system
US4111151A (en) * 1977-05-19 1978-09-05 Xerox Corporation Multi-particle developability regulating system
US5557393A (en) * 1994-11-04 1996-09-17 Xerox Corporation Process and apparatus for achieving customer selectable colors in an electrostatographic imaging system
JPH08248719A (ja) * 1995-03-14 1996-09-27 Ricoh Co Ltd 画像形成方法、並びに該方法に用いるトナー及び副剤パッケージ
JPH08248727A (ja) * 1995-03-14 1996-09-27 Ricoh Co Ltd 画像形成装置

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
GOODMAN N B: "CUSTOM COLOR LIQUID INK DEVELOPMENT", XEROX DISCLOSURE JOURNAL, vol. 21, no. 2, 1 March 1996 (1996-03-01), pages 155, XP000587140 *
PATENT ABSTRACTS OF JAPAN vol. 097, no. 001 31 January 1997 (1997-01-31) *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0964310A2 (de) * 1998-06-08 1999-12-15 Xerox Corporation System zur Farbenmischung und Steuerung für ein Druckgerät
EP0964310A3 (de) * 1998-06-08 2001-03-28 Xerox Corporation System zur Farbenmischung und Steuerung für ein Druckgerät
US7480070B2 (en) 2001-11-20 2009-01-20 Electronics For Imaging, Inc. Spot color pattern system

Also Published As

Publication number Publication date
JPH10104953A (ja) 1998-04-24
DE69726376T2 (de) 2004-08-19
EP0833220B1 (de) 2003-11-26
DE69726376D1 (de) 2004-01-08

Similar Documents

Publication Publication Date Title
US5899605A (en) Color mixing and color system for use in a printing machine
US5713062A (en) Color mixing and control system for use in an electrostatographic printing machine
US6938984B2 (en) Custom color inkjet printing system
US5897239A (en) Photometric color correction and control system for custom colors
EP1315049B1 (de) Hybridelektrophotographischer Apparat für Farbdruck nach Wunsch
JP4374178B2 (ja) カラーマッチング方法
US6002893A (en) High and low pigment loadings for custom colors
EP0833218B1 (de) System zur Farbenmischung und Nachfüllung für ein elektrostatographisches Druckgerät
US6526244B1 (en) Hybrid electrophotographic apparatus for custom color printing
EP0833220B1 (de) System zur Farbenmischung und Steuerung für ein elektrostatographisches Druckgerät
EP0833219A1 (de) System zur Farbenmischung und Steuerung für ein elektrostatographisches Druckgerät
US20040091286A1 (en) Method of development of custom colors without changing developer housing
US5512978A (en) Replenishing system
EP1304600B1 (de) Systeme und Methoden zur Flüssigtauchentwicklung
US6618564B2 (en) Electrophotographic development system with custom color printing
US10877406B2 (en) Printing by printing fluid transfer
Caruthers et al. Custom Color Printing With Liquid Toners
Gibson et al. Control of liquid Electrophoretic toner supplies
JPH04251870A (ja) 多色トナー混合系における帯電性測定方法

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE FR GB

RAX Requested extension states of the european patent have changed

Free format text: AL;LT;LV;RO;SI

17P Request for examination filed

Effective date: 19981001

AKX Designation fees paid

Free format text: DE FR GB

RBV Designated contracting states (corrected)

Designated state(s): DE FR GB

17Q First examination report despatched

Effective date: 20021205

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE FR GB

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

REF Corresponds to:

Ref document number: 69726376

Country of ref document: DE

Date of ref document: 20040108

Kind code of ref document: P

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed

Effective date: 20040827

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20130820

Year of fee payment: 17

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20130823

Year of fee payment: 17

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20130920

Year of fee payment: 17

REG Reference to a national code

Ref country code: DE

Ref legal event code: R119

Ref document number: 69726376

Country of ref document: DE

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20140919

REG Reference to a national code

Ref country code: DE

Ref legal event code: R119

Ref document number: 69726376

Country of ref document: DE

Effective date: 20150401

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

Effective date: 20150529

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20140919

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20150401

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20140930