Patents by Inventor Thomas E. Lewis

Thomas E. Lewis 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: 6168903
    Abstract: Imaging of lithographic printing plates with reduced fluence requirements is accomplished using printing members that have a solid substrate, gas-producing and radiation-absorptive layers over the substrate, and a topmost layer that contrasts with the substrate in terms of lithographic affinity. Exposure of the radiation-absorptive layer to laser light causes this layer to become intensely hot. This, in turn, activates the gas-producing layer, causing rapid evolution and expansion of gaseous decomposition products. The gases stretch the overlying topmost layer to create a bubble over the exposure region, where the imaging layers have been destroyed. If this process is sufficiently explosive, the neck of the bubble expands beyond the diameter of the incident laser beam, tearing the topmost layer and the underlying imaging layers away from the substrate outside the exposed region.
    Type: Grant
    Filed: January 21, 1999
    Date of Patent: January 2, 2001
    Assignee: Presstek, Inc.
    Inventors: Kenneth R. Cassidy, Thomas E. Lewis, Richard J. D'Amato
  • Patent number: 6107001
    Abstract: Methods and apparatus for lithographic imaging without ablation function by irreversibly debonding intermediate printing-plate layers, thereby rendering at least the surface layer removable by cleaning to expose, in an imagewise pattern, an underlying layer having a different affinity for ink and/or an abhesive fluid for ink. In contrast to ablation-type systems, it is unnecessary to destroy a plate layer, thereby reducing power requirements and facilitating increased imaging speeds.
    Type: Grant
    Filed: May 5, 1997
    Date of Patent: August 22, 2000
    Assignee: Presstek, Inc.
    Inventors: Thomas E. Lewis, Steven J. Frank
  • Patent number: 6095049
    Abstract: Apparatus and methods for imaging lithographic plates using laser devices that emit in the near-infrared region, and plates suitable for imaging with the apparatus and methods. Laser output either ablates one or more plate layers or physically transforms a surface layer, in either case resulting in an imagewise pattern of features on the plate. The image features exhibit an affinity for ink and/or a fluid to which ink will not adhere that differs from that of unexposed areas.
    Type: Grant
    Filed: October 7, 1999
    Date of Patent: August 1, 2000
    Assignee: Presstek, Inc.
    Inventors: Thomas E. Lewis, Richard A. Williams, Frank G. Pensavecchia, John F. Kline, John P. Gardiner, Michael T. Nowak, Kenneth T. Robichaud
  • Patent number: 6085656
    Abstract: The ability to clean ablation-type lithographic printing plates is enhanced by the formation of debris chemically compatible with a desired cleaning fluid. The debris may originate in the ablation layer of the printing member, or in a separate insulating layer disposed above the ablation layer.
    Type: Grant
    Filed: July 24, 1998
    Date of Patent: July 11, 2000
    Assignee: Presstak, Inc.
    Inventor: Thomas E. Lewis
  • Patent number: 6064009
    Abstract: A universal cable clamp for coupling a wide variety of electrical cables to an electrical box is capable of accepting metal or non-metallic sheathed cables. The cable clamp includes upper and lower clamping plates and a front wall having at least one opening for receiving the cable. The upper and lower clamping plates are coupled together by bendable coupling arms. A fastener extends through the upper and lower clamping plates and into the electrical box to deform the bendable coupling arms while the cable is clamped between the upper and lower clamping plates. The opening in the front wall in embodiments is oval-shaped and is dimensioned to allow a non-metallic sheathed cable to pass through, while preventing the metal sheath of a metal sheathed cable from passing through. The clamp provides a grounding connection of the metal cables and conduits. The cable clamp accommodates thick or thin steel and aluminum flex metal conduits, armored cable, metal clad cable and non-metallic cable.
    Type: Grant
    Filed: August 29, 1997
    Date of Patent: May 16, 2000
    Assignee: Hubbell Incorporated
    Inventors: Robert W. Jorgensen, Thomas E. Lewis, Richard D. Swanson
  • Patent number: 6055906
    Abstract: Defects of electrostatic origin in lithographic printing plates are prevented by reducing or minimizing the dielectric nature of the various plate layers. This lessens the capacitance of the system, reducing the voltage that results from a given deposited charge and, consequently, the likelihood of arcing. This may be accomplished by utilizing, for the substrate of the plate, a conductive film.
    Type: Grant
    Filed: November 4, 1998
    Date of Patent: May 2, 2000
    Assignee: Presstek, Inc.
    Inventor: Thomas E. Lewis
  • Patent number: 6045964
    Abstract: Constructions useful as lithographic printing plates include metallic inorganic layers exhibiting both hydrophilicity and substantial durability at very thin application levels. These materials ablatively absorb imaging radiation, thereby facilitating direct imaging without chemical development. They can also be used to form optical interference structures which, in addition to providing color, likewise absorb imaging radiation and ablate in response to imaging pulses.
    Type: Grant
    Filed: February 4, 1998
    Date of Patent: April 4, 2000
    Assignee: Presstek, Inc.
    Inventors: Ernest W. Ellis, Thomas E. Lewis
  • Patent number: 6024019
    Abstract: Lithographic printing constructions are removable from a permanent support, which may be a metal sheet affixable (usually by clamps) to a plate cylinder, or may instead be the permanent surface of such a cylinder. In this way, the traditional "plate" is replaced with a thin, easily manufactured printing member, which is separated from the support following its use.
    Type: Grant
    Filed: February 27, 1998
    Date of Patent: February 15, 2000
    Assignee: Presstek, Inc.
    Inventors: Richard A. Williams, Ernest W. Ellis, Thomas E. Lewis, Robert Howard
  • Patent number: 6006667
    Abstract: The performance-limiting effects of thermal breakdown on ablation-type lithographic printing plates are overcome by rendering the ink-accepting surface largely impervious to the effects of debris originating with the surface layer of the printing member, or by discouraging the formation of harmful debris altogether. In one approach, the ink-accepting surface is a highly crosslinked polymer. The resulting cured matrix exhibits a sufficient degree of three-dimensional bonding to resist melting, softening, or chemical degradation as a result of the imaging process. Alternatively, an intervening layer, disposed between the imaging layer and the surface layer, prevents the surface layer from undergoing significant thermal degradation in response to imaging radiation or ablation of the underlying imaging layer, and is also formulated to produce little debris or debris having an affinity for ink and/or fountain solution similar to the affinity of the substrate--e.g.
    Type: Grant
    Filed: March 12, 1998
    Date of Patent: December 28, 1999
    Assignee: Presstek, Inc.
    Inventor: Thomas E. Lewis
  • Patent number: 5996496
    Abstract: Apparatus and methods for imaging lithographic plates using laser devices that emit in the near-infrared region, and plates suitable for imaging with the apparatus and methods. Laser output either ablates one or more plate layers or physically transforms a surface layer, in either case resulting in an imagewise pattern of features on the plate. The image features exhibit an affinity for ink or an ink-abhesive fluid that differs from that of unexposed areas.
    Type: Grant
    Filed: February 11, 1997
    Date of Patent: December 7, 1999
    Assignee: Presstek, Inc.
    Inventors: Thomas E. Lewis, Richard A. Williams, Frank G. Pensavecchia, John F. Kline, John P. Gardiner, Michael T. Nowak, Kenneth T. Robichaud
  • Patent number: 5996498
    Abstract: The performance-limiting effects of thermal breakdown on ablation-type lithographic printing plates are overcome by rendering the ink-accepting surface largely impervious to the effects of debris originating with the surface layer of the printing member, or by discouraging the formation of harmful debris altogether. In one approach, the ink-accepting surface is a highly crosslinked polymer. The resulting cured matrix exhibits a sufficient degree of three-dimensional bonding to resist melting, softening, or chemical degradation as a result of the imaging process. Alternatively, an intervening layer, disposed between the imaging layer and the surface layer, prevents the surface layer from undergoing significant thermal degradation in response to imaging radiation or ablation of the underlying imaging layer, and is also formulated to produce little debris or debris having an affinity for ink and/or fountain solution similar to the affinity of the substrate--e.g.
    Type: Grant
    Filed: July 24, 1998
    Date of Patent: December 7, 1999
    Assignee: Presstek, Inc.
    Inventor: Thomas E. Lewis
  • Patent number: 5870955
    Abstract: Lithographic printing constructions are removable from a permanent support, which may be a metal sheet affixable (usually by clamps) to a plate cylinder, or may instead be the permanent surface of such a cylinder. In this way, the traditional "plate" is replaced with a thin, easily manufactured printing member, which is separated from the support following its use.
    Type: Grant
    Filed: March 5, 1997
    Date of Patent: February 16, 1999
    Assignee: Presstek, Inc.
    Inventors: Richard A. Williams, Ernest W. Ellis, Thomas E. Lewis, Robert Howard
  • Patent number: 5819661
    Abstract: Apparatus and methods for rapid, efficient production of durable lithographic printing plates by a thermal-transfer process that does not involve ablation. In response to an imaging pulse, a transfer material reduces in viscosity to a flowable state. The material exhibits a higher melt adhesion for a plate substrate than for the carrier sheet to which it is initially bound, so that in a flowable state it transfers completely to the substrate. Following transfer, the carrier sheet, along with untransferred material, is removed from the substrate.
    Type: Grant
    Filed: January 23, 1995
    Date of Patent: October 13, 1998
    Assignee: Presstek, Inc.
    Inventors: Thomas E. Lewis, Kenneth R. Cassidy
  • Patent number: 5783364
    Abstract: Constructions useful as lithographic printing plates include metallic inorganic layers exhibiting both hydrophilicity and substantial durability at very thin application levels. These materials ablatively absorb imaging radiation, thereby facilitating direct imaging without chemical development. They can also be used to form optical interference structures which, in addition to providing color, likewise absorb imaging radiation and ablate in response to imaging pulses.
    Type: Grant
    Filed: August 20, 1996
    Date of Patent: July 21, 1998
    Assignee: Presstek, Inc.
    Inventors: Ernest W. Ellis, Thomas E. Lewis
  • Patent number: 5704291
    Abstract: Printing members resistant to handling damage include a porous compressible layer that deforms in response to applied forces, inhibiting overlying layers from tearing or scratching. One type of construction involves ablation-type printing members, wherein pulses from a heat source ablate one or more layers to expose (or facilitate exposure of by cleaning) an underlying layer. A second type of construction utilizes traditional photoexposure-type layers that harden or increase adhesion to adjacent layers in response to actinic radiation. The compressible layer is typically located below the radiation-responsive or imaging layer, but may also serve as that layer.
    Type: Grant
    Filed: January 30, 1996
    Date of Patent: January 6, 1998
    Assignee: Presstek, Inc.
    Inventor: Thomas E. Lewis
  • Patent number: 5697300
    Abstract: Apparatus and methods for rapid, efficient production of durable lithographic printing plates by a thermal-transfer process that does not involve ablation. In response to an imaging pulse, a transfer material reduces in viscosity to a flowable state. The material exhibits a higher melt adhesion for a plate substrate than for the carrier sheet to which it is initially bound, so that in a flowable state it transfers completely to the substrate. Following transfer, the carrier sheet, along with untransferred material, is removed from the substrate.
    Type: Grant
    Filed: January 23, 1995
    Date of Patent: December 16, 1997
    Assignee: Presstek, Inc.
    Inventors: Thomas E. Lewis, Kenneth R. Cassidy
  • Patent number: 5649486
    Abstract: Laser-imageable, ablation-type lithographic printing members have a colorant that provides contrast between plate layers of similar tonalities. In particular, the colorant observably distinguishes the ablation layer from visible underlying layers, but which does not substantially interfere with the action of the imaging pulses.
    Type: Grant
    Filed: July 27, 1995
    Date of Patent: July 22, 1997
    Assignee: Presstek, Inc.
    Inventor: Thomas E. Lewis
  • Patent number: 5638753
    Abstract: Apparatus and methods for imaging lithographic plates using laser devices that emit in the near-infrared region, and plates suitable for imaging with the apparatus and methods. Laser output either ablates one or more plate layers or physically transforms a surface layer, in either case resulting in an imagewise pattern of features on the plate. The image features exhibit an affinity for ink or an ink-abhesive fluid that differs from that of unexposed areas.
    Type: Grant
    Filed: July 9, 1996
    Date of Patent: June 17, 1997
    Assignee: Presstek, Inc.
    Inventors: Thomas E. Lewis, Richard A. Williams, Frank G. Pensavecchia, John F. Kline, John P. Gardiner, Michael T. Nowak, Kenneth T. Robichaud
  • Patent number: 5636572
    Abstract: Seamless, sleeve-shaped dry and wet lithographic printing members that can be recycled after use include a strong, durable, hollow cylinder or sleeve that is attached to the plate mandrel or cylinder jacket of an offset printing press or platemaking apparatus. In one version, the sleeve is surrounded by a photopolymer, which is itself surrounded by a mask coating opaque to radiation that is actinic with respect to the photopolymer. Subsequently, the imaged construction is exposed to actinic radiation, and the unexposed photopolymer, along with the overlying mask, is removed by ordinary chemical means. In another version, a thermally transferable material surrounds a cylinder, and is itself surrounded by a withdrawal layer. Exposure of the thermally transferable layer to laser radiation adheres the transferable layer to the cylinder, and the adhered layer exhibits an affinity for fountain solution and/or ink opposite to that exhibited by the cylinder.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: June 10, 1997
    Assignee: Presstek, Inc.
    Inventors: Richard A. Williams, Thomas E. Lewis
  • Patent number: 5634403
    Abstract: Seamless, sleeve-shaped dry and wet lithographic printing members that can be recycled after use are disclosed, along with methods for their manufacture and use. The members include a strong, durable, hollow cylinder or sleeve that is attached to the plate mandrel or cylinder jacket of an offset printing press or platemaking apparatus. Surrounding the sleeve is a layer of a material, preferably polymeric in nature, which is characterized by efficient, ablative absorption of laser radiation, as well as other layers that facilitate imaging and subsequent printing. A layer disposed beneath the ablatable layer reflects unabsorbed imaging radiation back into the ablatable layer.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: June 3, 1997
    Assignee: Presstek, Inc.
    Inventors: Richard A. Williams, Thomas E. Lewis