Patents by Inventor Peter S. Alexandrovich

Peter S. Alexandrovich has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6432598
    Abstract: A process for forming a particulate yellow toner for the development of latent electrostatographic latent images comprises: combining dry Pigment Yellow 185 (P.Y. 185) and a first thermoplastic polymer under conditions effective to form a predispersion of P.Y. 185 in the polymer, and combining the predispersion with a second thermoplastic polymer under conditions effective to form a yellow toner composition, from which is formed yellow toner particles.
    Type: Grant
    Filed: June 27, 2001
    Date of Patent: August 13, 2002
    Assignee: Nexpress Solutions LLC
    Inventors: Peter S. Alexandrovich, Mark J. Stachowski, Dinesh Tyagi
  • Publication number: 20020025487
    Abstract: Methods for development of an electrostatic image are disclosed that utilize developer compositions with hard magnetic carrier compositions which can provide improved development efficiencies and reduced amounts of image carrier pick-up. The methods utilize hard magnetic carrier particles that are modified to have specific levels of resistivity, such as, for example, of from about 1×105 ohm-cm to about 1×1010 ohm-cm, and a carrier charge-to-mass of greater than about 1.0 &mgr;C/g, which carriers can provide greater development speeds without unacceptable levels of image carrier pick-up. In embodiments, the hard magnetic materials are doped, i.e., bulk substituted, with multi-valent metals to adjust resistivity, while in other embodiments, the hard magnetic materials are coated with at least one multi-valent metal oxide.
    Type: Application
    Filed: May 11, 2001
    Publication date: February 28, 2002
    Inventors: Patrick Lambert, Li C. Stelter, William K. Goebel, Peter S. Alexandrovich
  • Publication number: 20010046635
    Abstract: Disclosed are developer compositions for use in an electrographic development process and methods for using such compositions. The developer includes a hard magnetic material as a carrier, and also a toner material which comprises a polymeric resin, colorant, and a hydrophobic silica or hydrophilic silica, in an amount sufficient to reduce the dusting of toner particles off of the carrier particles during use, as well as to maintain the charge to mass ratio of the toner during use so as to increase the useful life of the developer composition. Also disclosed are methods of using such developer compositions.
    Type: Application
    Filed: May 11, 2001
    Publication date: November 29, 2001
    Inventors: Satyanarayan A. Srinivasan, Peter S. Alexandrovich, Robert D. Fields
  • Patent number: 6210851
    Abstract: An electrostatographic toner comprising toner particles that have been surface treated with a solvent and silica particles having a BET surface area of 40 to 400 m2/g; wherein the solvent is selected from aliphatic alcohols, diols and triols, aliphatic ketones, aliphatic esters, cyclic ethers and aliphatic ethers.
    Type: Grant
    Filed: December 1, 1999
    Date of Patent: April 3, 2001
    Assignee: Eastman Kodak Company
    Inventors: Satyanarayan A. Srinivasan, Peter S. Alexandrovich
  • Patent number: 5948585
    Abstract: A method of producing images includes forming an electrostatic latent image on a primary image forming member. A toner image is developed on the primary image forming member using a developer comprising dry toner particles having a mean volume weighted diameter D between 5 .mu.m and 10 .mu.m. The toner particles contain particulate addenda in a concentration range between (3.2/D)% and (5.6/D)%. The toner image is electrostatically transferred from the primary image forming member to an intermediate transfer member having a compliant layer, and then electrostatically transferred from the intermediate transfer member to a receiver.
    Type: Grant
    Filed: July 16, 1998
    Date of Patent: September 7, 1999
    Assignee: Eastman Kodak Company
    Inventors: Barrett L. Gady, Donald S. Rimai, Peter S. Alexandrovich, Salvatore Leone
  • Patent number: 5744274
    Abstract: There is provided an electrostatographic toner comprising a polymeric binder and a charge-control agent having the general structure: ##STR1## wherein A, B, R.sup.2, and R.sup.3 are defined in the specification.
    Type: Grant
    Filed: May 10, 1996
    Date of Patent: April 28, 1998
    Assignee: Eastman Kodak Company
    Inventors: John C. Wilson, Peter S. Alexandrovich
  • Patent number: 5723247
    Abstract: The image transfer properties and other properties of a fixable toner composition are made more stable by blending the binder resin of the toner with a multiphase organosiloxane block or graft condensation copolymer of low molecular weight which provides organosiloxane domains of particular size and concentration at the toner particle surfaces.
    Type: Grant
    Filed: February 28, 1997
    Date of Patent: March 3, 1998
    Assignee: Eastman Kodak Company
    Inventors: Robert A. Guistina, Peter S. Alexandrovich
  • Patent number: 5714293
    Abstract: There is provided a toner composition, useful in electrostatographic processes, comprising a polymeric binder and a charge-control agent having the general structure: ##STR1## wherein R.sup.
    Type: Grant
    Filed: May 10, 1996
    Date of Patent: February 3, 1998
    Assignee: Eastman Kodak Company
    Inventors: John C. Wilson, Peter S. Alexandrovich
  • Patent number: 5703265
    Abstract: A compound having the structure: ##STR1## is disclosed. R.sup.1 is defined in the specification. The compounds are charged control agents for use in electrostatographic toners and developers.
    Type: Grant
    Filed: May 10, 1996
    Date of Patent: December 30, 1997
    Assignee: Eastman Kodak Company
    Inventors: John C. Wilson, Peter S. Alexandrovich
  • Patent number: 5700611
    Abstract: First and second toner images (usually of different color) are formed which at least partially overlap. The first toner image is crated by electronically exposing, pixel-by-pixel, a uniformly charged image member, to create a first electrostatic image and toning that image with toner of a first color. A second electrostatic image is formed by electronically exposing the image member according to a second electronic signal. The exposure of each pixel in the second exposure is adjusted to compensate for a change in electric field caused by any presence of toner from the first exposure in that pixel. The second electrostatic image is toned by toner of a second color to create a multicolor image with portions that overlap.
    Type: Grant
    Filed: December 7, 1995
    Date of Patent: December 23, 1997
    Assignee: Eastman Kodak Company
    Inventors: Michael T. Regan, Peter S. Alexandrovich
  • Patent number: 5681680
    Abstract: There is provided a compound, useful in electrostatographic processes in the toner composition along with a polymeric binder, having the general structure: ##STR1## wherein R.sup.1 is selected from the group consisting of alkylene; arylene; arylenedialkylene; alkylenediarylene; oxydialkylene; and substituted or unsubstituted oxydiarylene; andR.sup.2 and R.sup.3, which can be the same or different, are independently selected from the group consisting of alkyl containing from 1 to 20 carbons; cycloalkyl containing from 3 to 18 carbons; unsubstituted aromatic ring systems; or aromatic ring systems substituted with one or more alkyl, hydroxy, alkoxy, carboxy, carboalkoxy, nitro, halo, cyano, amino, dialkylamino, acyl, trihalomethyl or alkylsulfonyl; heteroaromatic ring systems; said ring systems having a solitary ring or 2 to 3 linked or fused rings, and containing from 3 to 34 carbons; and R.sup.
    Type: Grant
    Filed: May 10, 1996
    Date of Patent: October 28, 1997
    Assignee: Eastman Kodak Company
    Inventors: John C. Wilson, Peter S. Alexandrovich
  • Patent number: 5678131
    Abstract: In an electrostatographic process wherein images are formed on an electrostatic image supporting medium and developed by a development station having a developer formed of a mixture of toner and carrier particles, there is provided apparatus for controlling various processing control parameters in response to formation of a toned patch on the medium. The apparatus includes a first feedback controller that processes signals related to the parameter toning contrast in accordance with a closed loop control of this parameter. The first feedback controller serves as a toning contrast controller and outputs a first signal representing toner concentration set point in response to closed loop control of toning contrast. The apparatus also includes a second feedback controller means that is slaved to the first feedback controller and serves as a toner concentration (TC) controller.
    Type: Grant
    Filed: April 9, 1996
    Date of Patent: October 14, 1997
    Assignee: Eastman Kodak Company
    Inventors: Peter S. Alexandrovich, Allen J. Rushing
  • Patent number: 5616797
    Abstract: An electrophotographic toner having polymeric binder and a charge control agent selected from the group consisting of sulfonamides having the general structure: ##STR1## and metal salts thereof. T.sup.1 is independently selected from H, alkyl having from 1 to 20 carbons, cycloalkyl having from 3 to 18 carbons, and aromatic and heteroaromatic ring systems having a solitary ring or 2 to 3 linked or fused rings. R.sup.1 is O, S, N--H, N--R.sup.5, or N--L--R.sup.5 ; where L is a linking group selected from: ##STR2## and R.sup.5 is independently selected from alkyl having from 1 to 20 carbons, cycloalkyl having from 3 to 18 carbons, and aromatic and heteroaromatic ring systems having a solitary ring or 2 to 3 linked or fused rings. L.sup.1 and L.sup.2 are each independently a direct link or divalent alkyl or fluoroalkyl having from 1 to 20 carbons. R.sup.a and R.sup.
    Type: Grant
    Filed: December 9, 1994
    Date of Patent: April 1, 1997
    Assignee: Eastman Kodak Company
    Inventors: John C. Wilson, Peter S. Alexandrovich, Steven M. Bonser
  • Patent number: 5523484
    Abstract: An electrophotographic toner having polymeric binder and a charge control agent selected from the group consisting of sulfonamides having the general structure: ##STR1## Each R.sup.1 is independently O, S, N-H, N-R.sup.z, or N-L-R.sup.z ; where L is a linking group selected from: ##STR2## and R.sup.z is independently selected from the group consisting of alkyl having from 1 to 20 carbons, cycloalkyl having from 3 to 18 carbons, and aromatic and heteroaromatic ring systems having a solitary ring or 2 to 3 linked or fused rings. R.sup.a, R.sup.b, and R.sup.c are each independently a ring system of a single ring or 2 or 3 fused or linked rings, said ring system having from 3 to 34 carbons, including substituent carbons. d is an integer from 0 to 3. e is an integer from 0 to 3. The sum of d+e is 2 or 3.
    Type: Grant
    Filed: September 30, 1994
    Date of Patent: June 4, 1996
    Assignee: Eastman Kodak Company
    Inventors: John C. Wilson, Peter S. Alexandrovich
  • Patent number: 5489975
    Abstract: An electrostatic image on an image member already containing a loose dry first toner image is toned with a second toner, for example, a toner of a second and different color from the first toner image. The toning is accomplished by a developer having a high coercivity permanently magnetized carrier and toner which is moved through a development zone by a rapidly rotating core inside a sleeve on which the developer moves. Pole transitions caused by the rapidly moving core make the high coercivity permanently magnetized carrier move vigorously in a wave motion having alternating crests and troughs. Scavenging of the first toner image is prevented by separating the sleeve from the image member sufficiently that the crests of the developer do not touch the image member during the toning process. An alternating electrical field is applied between the sleeve and the image member to enhance development.
    Type: Grant
    Filed: March 13, 1995
    Date of Patent: February 6, 1996
    Assignee: Eastman Kodak Company
    Inventors: Joseph Y. Kaukeinen, Thomas A. Jadwin, Peter S. Alexandrovich, Eric C. Stelter
  • Patent number: 5409791
    Abstract: An electrostatic image on an image member already containing a loose dry first toner image is toned with a second toner, for example, a toner of a second and different color from the first toner image. The toning is accomplished by a developer having a high coercivity permanently magnetized carrier and toner which is moved through a development zone by a rapidly rotating core inside a sleeve on which the developer moves. Pole transitions caused by the rapidly moving core make the high coercivity permanently magnetized carrier move vigorously in a wave motion having alternating crests and troughs. Scavenging of the first toner image is prevented by separating the sleeve from the image member sufficiently that the crests of the developer do not touch the image member during the toning process. An alternating electrical field is applied between the sleeve and the image member to enhance development.
    Type: Grant
    Filed: May 20, 1993
    Date of Patent: April 25, 1995
    Assignee: Eastman Kodak Company
    Inventors: Joseph Y. Kaukeinen, Thomas A. Jadwin, Peter S. Alexandrovich, Eric C. Stelter
  • Patent number: 5405727
    Abstract: An electrophotographic toner having polymeric binder and a charge control agent selected from the group consisting of sulfonamides having the general structure: ##STR1## and metal salts thereof. T.sup.1 is independently selected from H, alkyl having from 1 to 20 carbons, cycloalkyl having from 3 to 18 carbons, and aromatic and heteroaromatic ring systems having a solitary ring or 2 to 3 linked or fused rings. R.sup.1 is O, S, N--H, N--R.sup.5, or N--L--R.sup.5 ; where L is a linking group selected from: ##STR2## and R.sup.5 is independently selected from alkyl having from 1 to 20 carbons, cycloalkyl having from 3 to 18 carbons, and aromatic and heteroaromatic ring systems having a solitary ring or 2 to 3 linked or fused rings. L.sup.1 and L.sup.2 are each independently a direct link or divalent alkyl or fluoroalkyl having from 1 to 20 carbons. R.sup.a and R.sup.
    Type: Grant
    Filed: December 22, 1993
    Date of Patent: April 11, 1995
    Assignee: Eastman Kodak Company
    Inventors: John C. Wilson, Peter S. Alexandrovich, Steven M. Bonser
  • Patent number: 5385800
    Abstract: An electrophotographic toner having polymeric binder and a charge control agent selected from the group consisting of sulfonamides having the general structure: ##STR1## Each R.sup.1 is independently O, S, N--H, N--R.sup.z, or N--L--R.sup.z ; where L is a linking group selected from: ##STR2## and R.sup.z is independently selected from the group consisting of alkyl having from 1 to 20 carbons, cycloalkyl having from 3 to 18 carbons, and aromatic and heteroaromatic ring systems having a solitary ring or 2 to 3 linked or fused rings. R.sup.a, R.sup.b, and R.sup.c are each independently a ring system of a single ring or 2 or 3 fused or linked rings, said ring system having from 3 to 34 carbons, including substituent carbons. d is an integer from 0 to 3. e is an integer from 0 to 3. The sum of d+e is 2 or 3.
    Type: Grant
    Filed: December 22, 1993
    Date of Patent: January 31, 1995
    Assignee: Eastman Kodak Company
    Inventors: John C. Wilson, Peter S. Alexandrovich
  • Patent number: 5376492
    Abstract: A two component development system includes developer with charged toner particles and oppositely charged carrier particles having high coercivity and permanent magnetism. The developer is moved through a development zone on a shell and into contact with an image member carrying an electrostatic image by rapidly rotating a magnetic core within the shell. The core has alternating magnetic poles around its periphery. To prevent carryout of carrier on the image member, an AC bias is impressed across the development zone.
    Type: Grant
    Filed: May 20, 1993
    Date of Patent: December 27, 1994
    Assignee: Eastman Kodak Company
    Inventors: Eric C. Stelter, Peter S. Alexandrovich, Joseph E. Guth
  • Patent number: 5300384
    Abstract: A method of forming a toner image on a receiving sheet includes a step of either transferring or fixing a toner image to the receiving sheet, in which the receiving sheet is heated to a temperature of at least 100.degree. C. To allow steam to escape from the receiving sheet, a gas impermeable layer on the side of the sheet opposite the toner image is made permeable by application of small, closely spaced holes in the layer. The method is particularly usable with a receiving sheet having a heat-softenable layer which is heated beyond its softening point to facilitate transfer of images made up of very small toner particles. The holes are preferably mechanically punched in a curl-preventing layer on the opposite side of the sheet.
    Type: Grant
    Filed: August 24, 1992
    Date of Patent: April 5, 1994
    Assignee: Eastman Kodak Company
    Inventors: Donald S. Rimai, Dinesh Tyagi, William A. Light, Peter S. Alexandrovich, Douglas E. Bugner