Abstract: A liquid crystal display is made from an encapsulated liquid crystal structure comprising a liquid crystal composition dispersed in a containment medium. Selected additives may be added to the encapsulated liquid crystal structure to improve performance characteristics such as the operating field, the hysteresis, and the voltage holding ratio.
Type:
Grant
Filed:
April 4, 1995
Date of Patent:
January 16, 1996
Assignee:
Raychem Corporation
Inventors:
Mark F. Wartenberg, Harriette Atkins, Robert H. Reamey, Laurence Welsh, James Strain, Janusz Wojtowicz, Wayne Montoya, Paul S. Drzaic, John Havens, Akira Tomita, Aldrich N. K. Lau
Abstract: A chiral nematic liquid crystal-polymer composite capable of having a paper-white off-state and a highly transparent on-state. The composite includes droplets of at least two different liquid crystal materials. The different liquid crystal materials are isolated from each other and have different reflection bands. The composite is suitable for use in light valves generally and direct view and projection displays particularly.
Abstract: A porcelain having 9 to 55% by weight of SiO.sub.2, 36 to 87% by weight of Al.sub.2 O.sub.3, 0 to 2.0% by weight of Fe.sub.2 O.sub.3, 0 to 1.0% by weight of TiO.sub.2, 0 to 0.5% by weight of CaO, 0 to 0.5% by weight of MgO, 1.0 to 4.0% by weight of K.sub.2 O and Na.sub.2 O combined, and 0.25 to 25.0% by weight of bismuth oxide is disclosed. The porcelain has unexpectedly high unglazed bending strength and may be used for dielectric and structural applications.
Type:
Grant
Filed:
August 29, 1994
Date of Patent:
October 24, 1995
Assignee:
Raychem Corporation
Inventors:
Karin M. Kinsman, Ryan W. Dupon, Martha L. McCrum, Linas Mazeika, Amy S. Chu
Abstract: A generally-planar polymeric protective shield (2) for mounting on a high voltage porcelain insulator (16) has circumferential and radial intersecting grooves (8,10) in its upper surface. The intersections are deepened to provide point projections (12) from the lower surface thereby to space the major portion of the shield (2) from the insulator (16). The convoluted upper surface of the shield (2) enhances the physical protection of the porcelain of the insulator (16).
Abstract: Gels of hard-elastomer-hard block copolymers with at least 300 parts of extending liquid per 100 parts of the copolymer contain at least 50 parts (per 100 parts of copolymer) of a stabilizing additive which resists migration of PVC plasticizers into the gel when in contact with a plasticized PVC article. Styrene-(ethylene-butylene)-styrene triblock copolymers with organic phosphate stabilizers are preferred, these stabilizers tending to raise the gel softening temperature.
Type:
Grant
Filed:
November 10, 1993
Date of Patent:
August 15, 1995
Assignee:
Raychem Limited
Inventors:
Alistair A. P. Sutherland, John M. Hudson
Abstract: Flame retarded organopolysiloxane gels suitable for sealing and protecting electrical contacts include (i) an organopolysiloxane gel having repeat units of the structure ##STR1## where each R is independently phenyl or C.sub.1 -C.sub.4 alkyl or fluoroalkyl, at least 40% of the R groups being phenyl; and (ii) an additive package mixed with the organopolysiloxane, which is (a) zinc oxide; (b) antimony oxide; (c) a brominated compound having a molecular weight of at least 450 and a bromine content of at least 40 weight %; (d) a chlorinated compound having a molecular weight of at least 300 and a chlorine content of at least 40 weight %; or (e) combinations of the above. The additive package is used in an amount between about 10 and about 60 parts by weight per 100 parts by weight of organopolysiloxane.
Type:
Grant
Filed:
December 1, 1993
Date of Patent:
August 15, 1995
Assignee:
Raychem Corporation
Inventors:
Achilles Chiotis, Rejendra S. Cornelius, Pravin L. Soni
Abstract: Novel aromatic poly(ether ketones) having imide, amide, ester, azo, quinoxaline, benzimidazole, benzoxazole, or benzothiazole groups, comprising, for example, a repeat unit ##STR1## are prepared by Friedel Crafts polymerization.
Type:
Grant
Filed:
June 29, 1989
Date of Patent:
July 25, 1995
Assignee:
Raychem Corporation
Inventors:
Klaus J. Dahl, Patrick J. Horner, Heinrich C. Gors, Viktors Jansons, Richard H. Whiteley
Abstract: A liquid crystal display is made from an encapsulated liquid crystal structure comprising a liquid crystal composition dispersed in a containment medium. Selected additives may be added to the encapsulated liquid crystal structure to improve performance characteristics such as the operating field, the hysteresis, and the voltage holding ratio.
Type:
Grant
Filed:
March 9, 1993
Date of Patent:
June 27, 1995
Assignee:
Raychem Corporation
Inventors:
Mark F. Wartenberg, Harriette Atkins, Robert H. Reamey, Laurence Welsh, James Strain, Janusz Wojtowicz, Wayne Montoya, Paul S. Drzaic, John Havens, Akira Tomita, Aldrich N. K. Lau
Abstract: A method is described for making a liquid crystal composite in which droplets of a liquid crystal material dispersed in a matrix material. An encapsulating material at least partially separates the liquid crystal material from the matrix material. This construction permits the matrix material to be selected on the basis of its processing and environmental properties and the encapsulating material to be selected on the basis of its emulsifying ability and orientational interactions with liquid crystal material. Light valves made from such a composite exhibit improved electro-optical properties.
Type:
Grant
Filed:
March 24, 1994
Date of Patent:
April 11, 1995
Assignee:
Raychem Corporation
Inventors:
Robert H. Reamey, John Mazzanti, Mark Wartenberg, Gil Garza, John Havens, Anne Gonzales, Kathleen DiZio, Harriette Atkins, Kevin Malloy
Abstract: A close-fitting box (110, 120 FIG. 3) maintains a sheet (100) of mastic in sheet form for wrapping around a cable splice (FIG. 7) to supply large volume of mastic to fill the enclosure formed by applying a heat-shrinkable sleeve (250, FIG. 11) around the mastic-wrapped splice.
Abstract: A color projection display uses a dichroic cube for modulating the color of light reaching the imaging element of the display. This way, a colored image may be projected by frame sequential technique, but with the use of only a single imaging element.
Abstract: Telomers of the structure ##STR1## are disclosed, where R is --CH.sub.3 or H; R' is a C.sub.5 to C.sub.18 alkyl or fluoroalkyl group; n is an integer between 2 and 6 inclusive; and x is an integer between 3 and 26 inclusive. These telomers are surface active and are useful as aids for coating applications.
Abstract: An electrical insulator comprising a cylindrical core (2) of an insulating refractory material, such as porcelain, onto a portion of the curved surface of which a sleeve (8) of insulating polymeric material is fitted. Metal end-caps (4), for electrically connecting the insulator, are fitted to the ends of the porcelain core such that there is an exposed portion (10) of the curved surface of the core between the sleeve and each end-cap. Thus, any damaging electrical activity which takes place at the metal end-caps is directed primarily onto the surface of the porcelain core (2), and not onto the surface of the electrically vulnerable polymeric sleeve (8), which serves to protect mechanically the relatively brittle porcelain core. Optionally, the polymeric sleeve (8) may have a convoluted or a shedded outer surface (12) to increase the leakage path length of the insulator, or to prevent the formation of a continuous moisture path, or both.
Abstract: A projector having a light valve which operates by alternatively transmitting incident light or scattering such light has adjustable illumination and projection apertures to maximize contrast ratio and brightness according to ambient light conditions.
Abstract: A sealed vented surge arrester and method of manufacture is described wherein the valve elements are held under compressive loading while strength members including a moisture sealing void filling compound are pressed fit from the sides of the unit with a shed applied over it. The design achieves all the desirable features of tubular strength members with an ease of manufacture from utilizing half-shell or more members which can be applied from the sides along the longitudinal axis of the valve elements during manufacture to provide better void filling between the structural members and the valve elements.
Type:
Grant
Filed:
June 18, 1992
Date of Patent:
November 8, 1994
Assignee:
Raychem Corporation
Inventors:
Gary H. Wiseman, William M. Robinson, Jeffrey A. Bennett, Ronald J. Mosso, John T. Fossett
Abstract: An encapsulated liquid crystal material which comprises a liquid crystal composition dispersed in a containmant medium and is responsive to an applied electric field to transform from a first visual state to a second visual state is made by: (a) providing a liquid crystal composition having an ordinary and an extraordinary refractive index; (b) providing a prepolymer material in which the liquid crystal composition is substantially immiscible and which is polymerizable into a containment medium having a refractive index which is substantially matched with the ordinary refractive index of the liquid crystal composition; (c) forming a dispersion of the liquid crystal composition in the prepolymer material, the dispersion having a mean volume diameter of less than 20 .mu.m; and (d) polymerizing the prepolymer material to form the encapsulated liquid crystal material.
Abstract: Encapsulated liquid crystal is deposited onto an electrode by providing a substrate having an electrode pattern thereon; placing the substrate and the electrode pattern in contact with an electrodeposition medium comprising a liquid crystal composition, a containment medium or precursor therefor, and optionally a carrier medium; and depositing encapsulated liquid crystal material comprising the liquid crystal composition dispersed in the containment medium onto the electrode pattern or selected portions thereof by applying a voltage to the electrode pattern or selected portions thereof. The coated substrate-electrode combination can then be made into displays, privacy screens, signs, architectural partitions, and the like.
Abstract: A liquid crystal projection display, having (a) a light source for producing light of at least two different primary colors; (b) an imaging element corresponding to each primary color light produced by the light source, each imaging element comprising plural pixel elements, each pixel element comprising liquid crystal composition dispersed in plural volumes in a containment medium and being independently addressable to primarily scatter light incident thereon in the absence of a sufficient electric field and to primarily transmit light incident thereon in the presence of a sufficient electric field; and (c) a lens for projecting light transmitted by each imaging element onto a screen; the liquid crystal composition in the pixel elements of the imaging element corresponding to the primary color light of longest wavelength including a pleochroic dye of a color complementary to the primary color light of longest wavelength, which pleochroic dye preferentially absorbs incident light which has not been scattered b
Type:
Grant
Filed:
May 19, 1992
Date of Patent:
April 26, 1994
Assignee:
Raychem Corporation
Inventors:
Philip J. Jones, Wayne Montoya, Hundi P. Kamath, Akira Tomita
Abstract: Aromatic bistriazene compounds of the formula ##STR1## wherein --R.sub.1, --R.sub.2, --R.sub.3, and --R.sub.4 are independently --H, --C.sub.6 H.sub.5, --C.sub.6 H.sub.4 Y, or C.sub.1 -C.sub.4 alkyl; --R.sub.5 -- is ##STR2## --R.sub.6 is --F, --Cl, --Br, --CH.sub.3, or --CF.sub.3 ; r is 0, 1, 2, 3, or 4; and --Y is halogen, --NO.sub.2, --C.sub.6 H.sub.5, or C.sub.1 -C.sub.4 alkyl. These bistriazene compounds are useful for cross-linking polymers such as poly(imides), poly(aryl ether ketones), poly(aryl ether sulfones), poly(quinolines), poly(quinoxalines), and nonaromatic fluoropolymers having aliphatic C--H groups.
Type:
Grant
Filed:
November 17, 1992
Date of Patent:
December 14, 1993
Assignee:
Raychem Corporation
Inventors:
Aldrich N. K. Lau, Lanchi P. Vo, Frank W. Mercer