Patents Assigned to Presstek, Inc.
  • Patent number: 6868608
    Abstract: Printing plates are mounted onto a cylinder by first establishing a temperature difference between the plate and the cylinder; in particular, the temperature of the plate exceeds the temperature of the cylinder. The plate is then wrapped around the plate cylinder, and the temperature difference causes the plate to shrink against the cylinder.
    Type: Grant
    Filed: August 18, 2003
    Date of Patent: March 22, 2005
    Assignee: Presstek, Inc.
    Inventors: Edwin G. Theriault, James V. Lovenstein
  • Publication number: 20050039315
    Abstract: Printing plates are mounted onto a cylinder by first establishing a temperature difference between the plate and the cylinder; in particular, the temperature of the plate exceeds the temperature of the cylinder. The plate is then wrapped around the plate cylinder, and the temperature difference causes the plate to shrink against the cylinder.
    Type: Application
    Filed: August 18, 2003
    Publication date: February 24, 2005
    Applicant: Presstek, Inc.
    Inventors: Edwin Theriault, James Lovenstein
  • Patent number: 6851367
    Abstract: Systems and related methods are provided for modulating web tension loss at the edge of spool-hosting cavities in a cylinder by displacing the feed path and/or the exit path of the web material.
    Type: Grant
    Filed: July 31, 2003
    Date of Patent: February 8, 2005
    Assignee: Presstek, Inc.
    Inventors: Nandakumar Vaidyanathan, Steven Degon, Robert Bruce Lowd, Brian Roland Lamoureux, Keith Vaillancourt, James Hand
  • Patent number: 6810054
    Abstract: A laser-diode structure whose output is largely single-mode utilizes a ridged top layer that defines an amplification region within an underlying emission layer, and which is provided with grooves that suppress the higher modes.
    Type: Grant
    Filed: March 30, 2001
    Date of Patent: October 26, 2004
    Assignee: Presstek, Inc.
    Inventors: John Gary Sousa, Steven Stoltz
  • Patent number: 6715421
    Abstract: Metal-based printing members suitable for transfer-type imaging include a metal substrate and a hydrophilic, polymeric coating thereover. Desirably, the polymeric coating is crosslinked and withstands repeated application of fountain solution during printing. The polymeric coating can, however, undergo degradation where exposed to fountain solution so long as the ink-receptive portions—the areas where oleophilic material has been transferred onto the hydrophilic coating—remain intact.
    Type: Grant
    Filed: March 1, 2002
    Date of Patent: April 6, 2004
    Assignee: Presstek, Inc.
    Inventor: Thomas E. Lewis
  • Publication number: 20040045995
    Abstract: Methods and apparatus to reduce or eliminate misalignment, wrinkles, and creases in coated web product. A relationship between web outgassing pressure and surface roughness of the web and web transporting rollers is developed. This relationship allows for the control over the web outgassing pressure. The ability to adjust the web tension pressure, as well as the selection of web transporting rollers with prescribed surface characteristics, allows an operator to control the degree to which the web floats over or tracks the web transporting roller. A controller, in response to pressure and tension sensors, can also provide dynamic, closed-loop control of the entire system.
    Type: Application
    Filed: September 9, 2003
    Publication date: March 11, 2004
    Applicant: PRESSTEK. INC.
    Inventors: Nandakumar Vaidyanathan, Robert Bruce Lowd
  • Publication number: 20040045994
    Abstract: Methods and apparatus to reduce or eliminate misalignment, wrinkles, and creases in coated web product. A relationship between web outgassing pressure and surface roughness of the web and web transporting rollers is developed. This relationship allows for the control over the web outgassing pressure. The ability to adjust the web tension pressure, as well as the selection of web transporting rollers with prescribed surface characteristics, allows an operator to control the degree to which the web floats over or tracks the web transporting roller. A controller, in response to pressure and tension sensors, can also provide dynamic, closed-loop control of the entire system.
    Type: Application
    Filed: September 9, 2003
    Publication date: March 11, 2004
    Applicant: PRESSTEK, INC.
    Inventors: Nandakumar Vaidyanathan, Robert Bruce Lowd
  • Publication number: 20040025726
    Abstract: Systems and related methods are provided for modulating web tension loss at the edge of spool-hosting cavities in a cylinder by displacing the feed path and/or the exit path of the web material.
    Type: Application
    Filed: July 31, 2003
    Publication date: February 12, 2004
    Applicant: Presstek, Inc.
    Inventors: Nandakumar Vaidyanathan, Steven Degon, Robert Bruce Lowd, Brian Roland Lamoureux, Keith Vaillancourt, James Hand
  • Publication number: 20040030439
    Abstract: A system of detecting and adjusting the normal force exerted by a web material around the circumferential surface of a cylinder is provided. Sensors associated with the cylinder surface are wired to a processor that compares detected normal web forces with a set value. An actuation device is activated by the processor to adjust the normal force exerted by the web by, e.g., adjusting the tension in the web material. A positioning device that preferably translates a web-wound spool is also provided as an option for the actuation device.
    Type: Application
    Filed: July 31, 2003
    Publication date: February 12, 2004
    Applicant: Presstek, Inc.
    Inventors: Nandakumar Vaidyanathan, Steven Degon, Robert Bruce Lowd, Brian Roland Lamoureux, Keith Vaillancourt, James Hand
  • Patent number: 6688227
    Abstract: A magnetic plate retention system especially suitable for use in retaining a lithographic plate material to a conventional plate cylinder utilizes one of more elongated retention devices selectively positioned anywhere along the outer circumferential surface of the plate cylinder parallel to the axis of rotation of the cylinder. The retention devices are applied, removed, and retained with an application/removal assembly.
    Type: Grant
    Filed: April 1, 2002
    Date of Patent: February 10, 2004
    Assignee: Presstek, Inc.
    Inventor: Samuel D. Zerillo
  • Patent number: 6684785
    Abstract: The present invention provides a printing member having a single radiation-absorptive multiphase layer over a substrate layer that may be imaged with or without ablation.
    Type: Grant
    Filed: March 1, 2002
    Date of Patent: February 3, 2004
    Assignee: Presstek, Inc.
    Inventor: Gerald P. Harwood, Jr.
  • Patent number: 6658914
    Abstract: A system for imparting and detecting mechanical energy includes a projectile and a hollow tube allowing the projectile to move therein. A portion of the projectile is allowed to emerge from one end of the tube and thereby transfer mechanical energy to a receiving entity, e.g., a wound roll of material. An actuator drives the projectile through the tube, and a first sensor detects when the protruding portion of the projectile extends from the tube to make contact with, for example, the core of the wound roll to start a timing sequence. A second sensor detects the arrival of the mechanical energy at, for example, the roll surface so that a comparison can be made between the start and end times.
    Type: Grant
    Filed: March 4, 2002
    Date of Patent: December 9, 2003
    Assignee: Presstek, Inc.
    Inventors: Nandakumar Vaidyanathan, Robert Bruce Lowd, Brian Roland Lamoureux, Stephen Dana Federico
  • Patent number: 6659323
    Abstract: Methods and apparatus to reduce or eliminate misalignment, wrinkles, and creases in coated web product. A relationship between web outgassing pressure and surface roughness of the web and web transporting rollers is developed. This relationship allows for the control over the web outgassing pressure. The ability to adjust the web tension pressure, as well as the selection of web transporting rollers with prescribed surface characteristics, allows an operator to control the degree to which the web floats over or tracks the web transporting roller. A controller, in response to pressure and tension sensors, can also provide dynamic, closed-loop control of the entire system.
    Type: Grant
    Filed: January 30, 2002
    Date of Patent: December 9, 2003
    Assignee: Presstek, Inc.
    Inventors: Nandakumar Vaidyanathan, Robert Bruce Lowd
  • Publication number: 20030183102
    Abstract: A magnetic plate retention system especially suitable for use in retaining a lithographic plate material to a conventional plate cylinder utilizes one of more elongated retention devices selectively positioned anywhere along the outer circumferential surface of the plate cylinder parallel to the axis of rotation of the cylinder. The retention devices are applied, removed, and retained with an application/removal assembly.
    Type: Application
    Filed: April 1, 2002
    Publication date: October 2, 2003
    Applicant: Presstek, Inc.
    Inventor: Samuel D. Zerillo
  • Patent number: 6626108
    Abstract: Lithographic imaging using non-ablative printing members combines the benefits of simple construction, the ability to utilize traditional metal base supports, and amenability to imaging with low-power lasers that need not impart ablation-inducing energy levels. A representative printing member has a hydrophilic metal substrate and, thereover, first and second layers. The first layer has a thickness and an exposed surface and comprises a material that absorbs imaging radiation. The second layer overlies the first layer and is oleophilic and substantially transparent to imaging radiation. Exposure to imaging radiation causes the first layer and the substrate to irreversibly detach without substantial ablation, thereby facilitating removal, by subjection to the cleaning liquid, of the first and second layers where detachment has taken place.
    Type: Grant
    Filed: January 15, 2002
    Date of Patent: September 30, 2003
    Assignee: Presstek Inc.
    Inventor: Thomas E. Lewis
  • Patent number: 6598526
    Abstract: Provided is a lithographic printing plate comprising a support substrate having disposed thereon an ablative-absorbing layer and, optionally, a durable, ink-accepting surface layer that is not ablative-absorbing. The ablative-absorbing layer may contain a high weight percent of an organic sulfonic acid component. The printing plate may further comprise a hydrophilic polymeric layer interposed between the ablative-absorbing layer and the substrate. The printing plate also comprises a primer layer underlying the ablative-absorbing layer with an adhesion-promoting agent, such as a zirconium compound, present in the primer layer. Also provided are methods of preparing such lithographic printing plates, and methods of preparing imaged lithographic printing plates from such lithographic printing plates by imagewise exposure to a laser and a subsequent cleaning step with water or with a cleaning solution.
    Type: Grant
    Filed: January 15, 2002
    Date of Patent: July 29, 2003
    Assignee: Presstek Inc.
    Inventors: Thomas P. Rorke, Richard J. D'Amato
  • Patent number: 6539859
    Abstract: A multicolor lithographic printing press utilizes a blanket member having a release surface with a transfer rate approaching 100%. This facilitates a press design utilizing a single blanket member to transfer multiple colors of ink onto a recording medium.
    Type: Grant
    Filed: October 15, 2001
    Date of Patent: April 1, 2003
    Assignee: Presstek, Inc.
    Inventor: Richard A. Williams
  • Patent number: 6497178
    Abstract: Provided is a lithographic printing plate comprising a support substrate having disposed thereon a hydrophilic layer interposed between the substrate and an ink-accepting ablative-absorbing surface layer. The ink-accepting surface layer comprising a one or more polymers and a sensitizer characterized by absorption of laser radiation. The printing plate may also comprise a primer layer underlying the ink-accepting surface layer with an adhesion-promoting agent present in the primer layer. Also provided are methods of preparing such lithographic printing plates, and methods of preparing imaged lithographic printing plates from such lithographic printing plates by imagewise exposure to a laser and a subsequent cleaning step with water or with a cleaning solution.
    Type: Grant
    Filed: October 30, 2000
    Date of Patent: December 24, 2002
    Assignee: Presstek, Inc.
    Inventors: Thomas P. Rorke, Richard J. D'Amato, Timothy J. Dunley, George R. Hodgins
  • Patent number: 6490975
    Abstract: Provided are methods of imaging a wet positive working lithographic printing member comprising the steps of providing a positive working printing member comprising a substrate, a hydrophilic layer, an infrared-absorbing layer, and, optionally, an ink-accepting surface layer; exposing the printing member to infrared layer imaging in an imagewise pattern removing by ablation not greater than 10% by weight, and most preferably none of the infrared-absorbing layer and optional ink-accepting surface layer; and removing with water the laser-exposed areas of the infrared-absorbing layer and optional ink-accepting surface layer to reveal the underlying hydrophilic layer. These methods are advantageous in reducing airborne debris and vapors during laser imaging, in increasing the speed of laser imaging, and in providing excellent cleanability and image quality. The printing member may further comprise a primer layer underlying the infrared-absorbing layer with an adhesion-promoting agent present in the primer layer.
    Type: Grant
    Filed: October 27, 2000
    Date of Patent: December 10, 2002
    Assignee: Presstek, Inc.
    Inventors: Thomas P. Rorke, Richard J. D'Amato, Timothy J. Dunley
  • Patent number: 6484637
    Abstract: Lithographic plate constructions include imaging layers having dispersed therein a radiation-scattering material and a radiation-absorbing material, both of which cooperate to increase the overall absorption of radiation in that layer. The radiation-scattering material may be in particulate form, the particles reflecting the imaging radiation from their surfaces. The use of particulate scattering material within the imaging layer creates a highly porous matrix that favors deep penetration of the imaging radiation and mechanical locking of the imaging layer to one or both adjacent layers. The scattering material may also be chosen also for its ability to chemically bind with an adjacent layer to increase intercoat adhesion.
    Type: Grant
    Filed: January 9, 2001
    Date of Patent: November 26, 2002
    Assignee: Presstek, Inc.
    Inventor: Thomas E. Lewis