Patents by Inventor Mitchell S. Cohen

Mitchell S. Cohen 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: 4617579
    Abstract: Electroerosion recording materials for "direct negative" and "offset master" are provided with a surface protective coating of solid conductive lubricant dispersed in a hydrophilic, crosslinked polymeric matrix. The protective films are especially useful where direct offset masters are produced without removal of non-eroded lubricant film.The recording medium of this invention provides use as a defect-free "direct negative" and/or "direct offset master", without requiring the removal of the overlayer prior to use on the printing press. The protective coatings are applied from aqueous dispersions of polymer-particulate compositions and thus avoiding the use of organic solvents.
    Type: Grant
    Filed: April 5, 1984
    Date of Patent: October 14, 1986
    Assignee: International Business Machines Corporation
    Inventors: Krishna G. Sachdev, Ali Afzali-Ardakani, Keith S. Pennington, Mitchell S. Cohen
  • Patent number: 4596733
    Abstract: For high speed electroerosion recording, this invention provides a polyorganosiloxane overlayer which includes high lubricity solid particles as a filler. The overlayer provides a combination lubricant and protective layer for the thin metal layer which is removed by electroerosion to prevent damage for the areas not removed by electroerosion. The polyorganosiloxane overlayer is preferably crosslinked, and is relatively hard, durable, and especially resistant to thermal degradation by the electroerosion arcing. This is important to avoid debris buildup at the recording electrodes resulting from the high temperature arcing for removal of the overlayer in the areas where recording takes place.
    Type: Grant
    Filed: December 30, 1983
    Date of Patent: June 24, 1986
    Assignee: International Business Machines Corporation
    Inventors: Mitchell S. Cohen, Keith S. Pennington, Krishna G. Sachdev, William D. Weber
  • Patent number: 4568621
    Abstract: Processes for thermal transfer printing are disclosed which comprise electroerosion printing to produce an image bearing element and exposing the imaged element to irradiation so as to permit transfer of thermographic ink from an associated ink layer or ink-containing element onto an ink receiving substrate thus producing copies of the image carried by the image bearing element. Also, described are products for use in such processes.
    Type: Grant
    Filed: October 22, 1984
    Date of Patent: February 4, 1986
    Assignee: International Business Machines Corporation
    Inventors: Ari Aviram, Mitchell S. Cohen
  • Patent number: 4567490
    Abstract: Electroerosion recording materials are provided with a surface lubricant film of particulate lubricating nonconductive graphite fluoride and optional conductive materials in a polymeric binder. The lubricating agents reduce stylus scratching of the conductive layer during electroerosion printing, improve contrast, provide a beneficial coating on the writing electrode or stylus and improve the handling and writing characteristics of the recording material. The lubricating agents/polymer films are especially useful (1) where the substrate of the recording material is light transmissive and, after the electroerosion process, the resulting product is suitable for direct-negative applications and (2) where direct offset masters are produced by removal of noneroded lubricant film.
    Type: Grant
    Filed: December 30, 1983
    Date of Patent: January 28, 1986
    Assignee: International Business Machines Corporation
    Inventors: Ali Afzali-Ardakani, Mitchell S. Cohen, Keith S. Pennington, Krishna G. Sachdev
  • Patent number: 4554562
    Abstract: Electroerosion recording materials of superior scratch resistance are provided without the need for a lubricant overcoat by incorporating a hard, lubricating hydrophobic polymer layer between the support and the removable, thin conductive layer to reduce plastic deformation of the support under stylus writing pressure. The intermediate polymer layer provides a highly adhering surface for the overlying aluminum film and contains graphite fluoride and/or fluorocarbon resins such as Teflon.RTM. and hard particles such as silica. The materials may be used in various printing processes including making directly readable images, direct negatives and wear resistant offset printing masters.
    Type: Grant
    Filed: December 30, 1983
    Date of Patent: November 19, 1985
    Assignee: International Business Machines Corporation
    Inventors: Ali Afzali-Ardakani, Mitchell S. Cohen, Keith S. Pennington, Krishna G. Sachdev
  • Patent number: 4550061
    Abstract: Improved electroerosion recording media are described in which ablatable polymers are used in the electroerosion recording medium. This medium includes at least a substrate or support layer, a base layer which protects the substrate, a thin film of conductive material on the base layer and which can be eroded, and a protective overcoat layer. Ablatable polymers are used as binders in either the base layer or the top protective layer, or both, in order to provide advantages during electroerosion. These ablatable polymers undergo thermally induced depolymerization in such a way that the result is the formation of volatile monomeric or low molecular weight species as the predominant products, with little or no adherent residue.
    Type: Grant
    Filed: April 13, 1984
    Date of Patent: October 29, 1985
    Assignee: International Business Machines Corporation
    Inventors: Krishna G. Sachdev, Stephen A. Shear, Keith S. Pennington, Mitchell S. Cohen
  • Patent number: 4283775
    Abstract: A bubble storage system using contiguous propagation elements is described using magnetically soft drive layers for movement of the bubble domains in a bubble domain film, in response to the reorientation of a magnetic drive field in the plane of the drive layers. In contrast with prior art contiguous element propagation structures, charged walls are not employed for movement of bubble domains. Instead, magnetic poles along the drive layers are used to move the domains. Two drive layers are used, each of which is comprised of a magnetically soft material, such as permalloy. The drive layers are located at different heights with respect to the layer in which the magnetic bubble domains exist, the bottom drive layer being comprised of contiguous propagation elements defining a generally undulating edge along which the magnetic bubble domains move. This layer can be comprised of permalloy contiguous disks, diamonds, etc.
    Type: Grant
    Filed: July 18, 1979
    Date of Patent: August 11, 1981
    Assignee: International Business Machines Corporation
    Inventor: Mitchell S. Cohen
  • Patent number: 4187553
    Abstract: An improved magnetic bubble domain chip and processes for making the chip are described. The chip is comprised of a magnetic bubble domain film in which small bubble domains can be moved, and overlying layers of metallurgy. The layer of metallurgy closest to the bubble film is an electrically conductive layer having apertures (or recesses) therein. This layer is patterned to provide current carrying conductors. The next overlayer is a layer of magnetic material having in-plane magnetization which is patterned to provide the propagation elements used to move the bubble domains. In a particular embodiment, the magnetic layer is comprised of a magnetically soft material, such as permalloy. The chip is characterized by the provision of insulating pedestals located in the apertures of the conductive layer. These insulating pedestals are located in the regions of the chip used for sensing (and/or bubble generation). That is, they take the place of the thick conductive material in those areas of the chip.
    Type: Grant
    Filed: December 23, 1977
    Date of Patent: February 5, 1980
    Assignee: International Business Machines Corporation
    Inventors: Kie Y. Ahn, Mitchell S. Cohen, John V. Powers, Lung-jo Tao
  • Patent number: 4174540
    Abstract: These improved current controlled transfer switches are particularly useful for changing the propagation path of very small bubble domains without requiring large amounts of transfer current. The underlying principle is that the transfer operation occurs when the magnitude of the magnetic drive field used to move bubble domains has diminished to a small value, or is zero. This means that the magnetic field due to current in the switch does not have to overcome the effect of the drive field and therefore can be very small while still being effective. This is termed a "start/stop" operation and in one embodiment, current-assisted transfer is achieved by utilizing a change in the sequence of the magnetic drive field (generally an in-plane rotating field) at the time of transfer. In another embodiment, a continuous "three-quadrant" magnetic drive field is used instead of the customary 360.degree. rotating drive field.
    Type: Grant
    Filed: June 30, 1977
    Date of Patent: November 13, 1979
    Assignee: International Business Machines Corporation
    Inventors: Mitchell S. Cohen, Emerson W. Pugh
  • Patent number: 4156936
    Abstract: SLM field access bubble devices which include at least one conductor crossing a bubble propagation path have severely limited operating margins (especially for small bubbles) for the bubble in the vicinity of the conductor. Apparatus and method for operating such a bubble device is disclosed which improves the device operation in this region. The improved apparatus and method provides an additional field source with a sense and magnitude to support the bubble when it reaches the conductor region. Such a field source, as disclosed, includes a current pulse in the conductor.
    Type: Grant
    Filed: May 31, 1977
    Date of Patent: May 29, 1979
    Assignee: International Business Machines Corporation
    Inventors: Gregory W. Beall, Mitchell S. Cohen, Mark H. Kryder