Solid Polymer Derived From Ethylenically Unsaturated Hydrocarbon Only Patents (Class 524/274)
  • Patent number: 4603174
    Abstract: A stretched polypropylene film having excellent see-through characteristics, which is prepared by stretching in at least one direction a polypropylene resin sheet containing 0.05 ppm to 10,000 ppm by weight of a 3-position branched .alpha.-olefin unit and/or a vinyl cycloalkane unit, each having at least 6 carbon atoms.
    Type: Grant
    Filed: December 27, 1984
    Date of Patent: July 29, 1986
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Tadayuki Okada, Masahiro Kakugo, Yoshiharu Fukui, Kizuku Wakatsuki, Seiichiro Ima, Junichi Kimura
  • Patent number: 4590230
    Abstract: Disclosed herein is an adhesive composition which contains specific amounts of (A) an aqueous emulsion, (B) a filler and (C) a resin solution of a resinous tackifier dissolved in a solvent and/or plasticizer. The adhesive composition has a fast setting time in adhesion strength and excellent water-proofness and hence produces superb adhesion force even when applied to a fresh mortar base which has been aged insufficiently.
    Type: Grant
    Filed: September 4, 1984
    Date of Patent: May 20, 1986
    Assignee: Mitsui Toatsu Chemicals, Incorporated
    Inventors: Keiichi Kamada, Katuaki Iiyama, Yasushi Yano, Isao Itoh
  • Patent number: 4581400
    Abstract: A rubber composition comprising (a) 100 parts by weight of a rubber selected from the group consisting of natural rubber and synthetic diene rubbers and (b) about 1 to about 30 parts by weight of a rosin derivative comprising a blend of (i) about 15 to about 50% by weight of a rosin, (ii) about 10 to about 70% by weight of a polymerized rosin and (iii) not more than about 55% by weight of a rosin pitch, each based on the weight of the rosin derivative.
    Type: Grant
    Filed: March 27, 1985
    Date of Patent: April 8, 1986
    Assignee: Bridgestone Corporation
    Inventor: Hitoshi Kondo
  • Patent number: 4568713
    Abstract: Hot melt adhesives with long open time and good cold metal bonding are made of blends of an at least partially crystalline copolymer of butene-1 and ethylene, an aliphatic, substantially non-polar resin, an antioxidizing agent and, optionally, microcrystalline wax.
    Type: Grant
    Filed: May 30, 1984
    Date of Patent: February 4, 1986
    Assignee: Shell Oil Company
    Inventors: David R. Hansen, David J. St. Clair
  • Patent number: 4556464
    Abstract: A cured adhesive composition possessing high cohesive strength at high temperatures along with excellent shear strength and solvent resistance prepared using a block copolymer containing carbon-carbon double bonds in the endblocks which are crosslinked by a crosslinking agent preferentially compatible with the endblock phase.
    Type: Grant
    Filed: April 29, 1985
    Date of Patent: December 3, 1985
    Assignee: Shell Oil Company
    Inventor: David J. St. Clair
  • Patent number: 4551490
    Abstract: Medical grade pressure sensitive adhesive compositions comprising a homogeneous mixture of one or more polyisobutylenes or blends of one or more polyisobutylenes and butyl rubber, one or more styrene radial or block type copolymers, mineral oil, one or more water soluble hydrocolloid gums, and a tackifier. One or more water swellable cohesive strengthening agents, an antioxidant, and various other optional ingredients may be included within the adhesive composition.
    Type: Grant
    Filed: December 30, 1983
    Date of Patent: November 5, 1985
    Assignee: E. R. Squibb & Sons, Inc.
    Inventors: Arthur Doyle, Frank M. Freeman
  • Patent number: 4548845
    Abstract: A water-insoluble, normally tacky, pressure-sensitive adhesive is disclosed having reduced build up on a knife blade when that knife blade is utilized to shear a plurality of webs including a layer of the adhesive. The adhesive contains a mixture of non-volatile components including (a) a water-insoluble elastomeric polymer, (b) a tackifier and (c) a polyoxyalkylene polyol present in amount of about 3 to about 45 percent of the total non-volatile weights of components (a), (b) and (c). The adhesive components (a), (b) and (c) are dispersed substantially homogeneously when the adhesive is applied to a substrate.
    Type: Grant
    Filed: April 21, 1983
    Date of Patent: October 22, 1985
    Assignee: Avery International Corp.
    Inventors: Robert E. Parsons, Martha L. Westcott, Susan L. Johnson
  • Patent number: 4536218
    Abstract: Printed materials such as tickets, lottery forms, cards and contest forms, bearing a hidden message which is revealable by scratching off a covering opaque layer, are prepared by printing the message on the substrate, lithographing a protective layer such as a clear varnish or a pigmented varnish-ink over the hidden message, and then lithographing a hiding coat over the applied protective layer. The protective layer formulation and the hiding coat layer are both based upon compatible, preferably the same, film forming resin systems, and are deposited from a common solvent. The protective layer may provide a clear, colorless transparent film through which the message may be viewed, or a colored see-through layer, so that it constitutes one color layer also for the printing of other areas of the substrate.
    Type: Grant
    Filed: February 8, 1984
    Date of Patent: August 20, 1985
    Inventor: Eli A. Ganho
  • Patent number: 4535013
    Abstract: A low temperature binder systen for non-woven polyolefin fabrics and corresponding method for increasing multidirectional web strength thereof whereby the corresponding fiber web is contacted by a system comprised of a copolymer or terpolymer modified with an active amount of a resin ester component of limited abietic acid concentration, of a hydrogenated resin and a glycerol or pentaerythritol, the latter having a specified softening point and molecular weight range.
    Type: Grant
    Filed: August 15, 1983
    Date of Patent: August 13, 1985
    Inventor: Beryl M. Kuhn
  • Patent number: 4521493
    Abstract: A resin-modified fiber filter formulation, fiber filter element, and method for improving dimensional stability, firmness and resiliency of a polyolefin fiber filter element comprised of crimped polyolefin fiber tow, by contacting filaments thereof with a formulation comprising a blend of resin and base polymer emulsions as precursors forming the active formulation "in situ", at a convenient station by removing water, the solid resin component of which must have a low molecular weight and approved softening temperature range to obtain the desired characteristics.Typical resins are polyterpenes and hydrogenated rosin esters; typical base polymers are polyvinyl acetate and copolymers thereof with, e.g., ethylene or acrylates.
    Type: Grant
    Filed: January 12, 1984
    Date of Patent: June 4, 1985
    Assignee: Hercules Incorporated
    Inventor: Jay B. Class
  • Patent number: 4518733
    Abstract: A rubber composition comprising, in specific mixing ratios, rubber material consisting mainly of natural rubber and/or synthetic polyisoprene rubber, a cobalt salt of rosin, carbon black having specific iodine adsorbability and dibutyl phthalate absorbability, and sulphur.
    Type: Grant
    Filed: February 6, 1984
    Date of Patent: May 21, 1985
    Assignee: The Yokohama Rubber Co., Ltd.
    Inventors: Yasuhiro Ishikawa, Kazuhiro Yamada, Masashi Kida
  • Patent number: 4501846
    Abstract: Disclosed is a pre-coat composition consisting essentially of (1) a low density polyethylene having a melt index of from about 70 to about 425; (2) a nitrogen-containing silane cross-linking compound, (3) a resin having a Ring and Ball softening point from about 50.degree. C. to about 115.degree. C.; (4) a hydrocarbon wax; and (5) optionally naphthenic oil. The composition is useful in the manufacture of tufted carpets.
    Type: Grant
    Filed: June 30, 1983
    Date of Patent: February 26, 1985
    Assignee: Hercules Incorporated
    Inventor: Raymond W. Goss
  • Patent number: 4497931
    Abstract: Antioxidants are enhanced in their activity by the presence of soluble lithium ion.
    Type: Grant
    Filed: July 1, 1983
    Date of Patent: February 5, 1985
    Assignee: Union Camp Corporation
    Inventor: Samuel D. Hollis
  • Patent number: 4491655
    Abstract: There is disclosed the use of esters especially methyl esters of rosin acids as total or partial replacements for oil in rubber formulations. Vulcanizate properties, low temperature performance, and processibility are comparable when using either the rosin ester or an aromatic oil, however, the rosin ester extended rubber demonstrates improved abrasion resistance and flex resistance.
    Type: Grant
    Filed: January 6, 1984
    Date of Patent: January 1, 1985
    Assignee: The Goodyear Tire & Rubber Company
    Inventor: Paul H. Sandstrom
  • Patent number: 4488646
    Abstract: A novel lottery ticket comprising a blush-type coating which coating is characterized by susceptibility to a change in appearance when exposed to either (a) any of a wide spectrum of organic solvents or (b) an elevated temperature. Such susceptibility reveals that solvent or thermal techniques have been used in tampering with the ticket or a pouch package in which the ticket is held. Such tampering is often the result of an illicit attempt to obtain information about the indicia printed on the ticket.
    Type: Grant
    Filed: October 3, 1983
    Date of Patent: December 18, 1984
    Assignee: Ludlow Corporation
    Inventor: James L. McCorkle
  • Patent number: 4478993
    Abstract: There is disclosed the use of decarboxylated rosins as total or partial replacements for oil in rubber formulations. Vulcanizate properties, low temperature performance, and processibility are comparable when using either the decarboxylated rosins or an aromatic extending oil, however, the decarboxylated rosin extended rubber demonstrates improved abrasion resistance.
    Type: Grant
    Filed: January 6, 1984
    Date of Patent: October 23, 1984
    Assignee: The Goodyear Tire & Rubber Company
    Inventors: Lawson G. Wideman, Paul H. Sandstrom
  • Patent number: 4472537
    Abstract: There are disclosed thermoplastic inks in the nature of high viscosity, tacky pastes which exhibit high cohesive strength, high pressure sensitivity at low temperatures, high thermal stability and low affinity for silicone surfaces. These properties make the inks particularly useful in those printing processes involving multiple elastomeric transfer members, in particular, those processes wherein silicone transfer members print successive colors onto a silicone collector which in turn transfers the multicolored print in a single step to ware or decal paper. The ink formulations consist essentially, in weight percent, of:(a) 50-80% of a pigmented, vitreous, inorganic flux;(b) 2-20% of a selected organic polymer;(c) 5-25% of a selected plasticizer;(d) 2-20% of a selected amorphous tackifying resin; and optionally,(e) up to 20% of an organic wax.
    Type: Grant
    Filed: August 22, 1983
    Date of Patent: September 18, 1984
    Assignee: Corning Glass Works
    Inventors: Ronald E. Johnson, Lung-ming Wu
  • Patent number: 4463120
    Abstract: A process for preparing an aqueous adhesive composition which comprises preparing a solvent dispersion by mixing rubber, carbon black, vulcanizing agent, tackifying resin and accelerator with sufficient organic solvent to form a solvent dispersion and thereafter emulsifying the solvent dispersion in the presence of water to form an aqueous emulsion. The aqueous emulsion may be used to bond unvulcanized rubber compounds, such as a tread stock to the carcass portion during the formation of a tire.
    Type: Grant
    Filed: January 24, 1983
    Date of Patent: July 31, 1984
    Assignee: SWS Silicones Corporation
    Inventors: Wendell Collins, Howard L. Brooks
  • Patent number: 4444953
    Abstract: A novel block copolymer having particular utility in adhesive compositions has the structure (A-B).sub.x Y(C).sub.z where A is a poly(monoalkenyl) block, B and C are poly(conjugated diene) polymer blocks, Y is the residue of a multifunctional coupling agent, and x plus z is greater than 6. Also disclosed are adhesive compositions containing such block copolymers.
    Type: Grant
    Filed: April 18, 1983
    Date of Patent: April 24, 1984
    Assignee: Shell Oil Company
    Inventor: David J. St. Clair
  • Patent number: 4440888
    Abstract: The hot-melt adhesives of the present invention comprise a blend of at least one modified polyethylene resin, a tackifying resin and a combination of halogenated organic compounds and inorganic compounds containing antimony, boron or tin. These hot-melt adhesives have a novel combination of properties including excellent aging properties in combination with improved strength and low viscosity, and they are fire resistant or self-extinguishing.
    Type: Grant
    Filed: June 28, 1982
    Date of Patent: April 3, 1984
    Assignee: Eastman Kodak Company
    Inventors: Mary J. Cook, Kenneth W. Hyche
  • Patent number: 4435477
    Abstract: Rubber compositions and metal-reinforced rubber ply members have improved metal adhesion and metal adhesion retention to brass and brass-plated metallic reinforcement. The improvement comprises admixing from about 0.5 to about 12.5 parts per hundred rubber (phr) of an organic salt of nickel and at least about 3.0 phr of a thermoplastic resin derived from crude wood rosin containing carboxylic acid groups or carboxylic acid ester groups with a vulcanizable rubber composition prior to embedding the metallic reinforcement therein and curing. A method for improving the metal adhesion and metal adhesion retention between a vulcanizable rubber and brass or brass-plated metallic reinforcement includes the steps of dispersing from about 0.5 to about 12.5 phr of an organic salt of nickel in a vulcanizable rubber composition and dispersing at least about 3.0 phr of the aforementioned thermoplastic resin in the same rubber composition prior to curing.
    Type: Grant
    Filed: July 25, 1983
    Date of Patent: March 6, 1984
    Assignee: The Firestone Tire & Rubber Company
    Inventor: James A. Davis
  • Patent number: 4433084
    Abstract: A high-float rapid-setting emulsion comprised of asphalt, tall oil, tall oil derivatives or mixtures thereof, copolymer selected from the group consisting of a styrene-butadiene-styrene block and styrene-isoprene-styrene block, petroleum distillate, water, and strong base. In addition, methods of manufacturing a high-float, rapid-setting emulsion including a first method comprising mixing asphalt with tall oil, tall oil derivatives or mixtures thereof, and combining and mixing said mixture with treated water comprising tall oil, tall oil derivatives or mixtures thereof, strong base, and water.
    Type: Grant
    Filed: September 28, 1982
    Date of Patent: February 21, 1984
    Assignee: K. E. McConnaughay, Inc.
    Inventors: Larry F. Ostermeyer, Michael N. Guerin
  • Patent number: 4432848
    Abstract: Pressure-sensitive adhesives with superior high temperature adhesion properties are prepared by radiation curing of an adhesive composition comprising a simple block copolymer as the elastomer component.
    Type: Grant
    Filed: November 19, 1981
    Date of Patent: February 21, 1984
    Assignee: Permacel
    Inventor: Ralf Korpman
  • Patent number: 4419470
    Abstract: Naturally occurring dark, tacky, low softening thermoplastic resins of low acid number can be used as substitutes for all or part of the non-elastomeric petroleum-derived components of rubber stocks used for manufacture of tires and other rubber articles. For example, such resins can be used to replace petroleum-derived process oils or resins, or both, used in making tires. The resins, which are derived from wood, are low softening thermoplastic resins characterized by having about 15-30% unsaponifiables, 3-20% rosin acids, 3-15% fatty acids and 5-15% sterols. A typical useful resin is commerically available under the name Pamak TP.
    Type: Grant
    Filed: March 19, 1982
    Date of Patent: December 6, 1983
    Assignee: The Firestone Tire & Rubber Company
    Inventors: James A. Davis, Robert C. Koch
  • Patent number: 4419494
    Abstract: Conventional hot melt adhesive formulations based on A-B-A type block copolymers are improved with respect to their heat and plasticizer resistance by addition thereto of a polymeric fatty acid polyamide.
    Type: Grant
    Filed: March 16, 1982
    Date of Patent: December 6, 1983
    Assignee: National Starch and Chemical Corporation
    Inventors: Paul P. Puletti, Catherine Stubler Salerno
  • Patent number: 4409359
    Abstract: Disclosed is a sealing compound for can ends excellent in the adaptability to the lining operation, which comprises an aqueous latex of a styrene-butadiene rubber, a tackifier and a filler, wherein said latex contains styrene-butadiene rubber particles having a number average particle size of from 1600 to 3000 A, which are stabilized by an emulsifier or a dispersant.
    Type: Grant
    Filed: February 10, 1982
    Date of Patent: October 11, 1983
    Assignee: Toyo Seikan Kaisha, Ltd.
    Inventors: Yusaburo Tanimura, Hideo Kumasaka
  • Patent number: 4407443
    Abstract: A novel lottery ticket comprising a blush-type coating which coating is characterized by susceptibility to a change in appearance when exposed to either (a) any of a wide spectrum of organic solvents or (b) an elevated temperature. Such susceptibility reveals that solvent or thermal techniques have been used in tampering with the ticket or a pouch package in which the ticket is held. Such tampering is often the result of an illicit attempt to obtain information about the indicia printed on the ticket.
    Type: Grant
    Filed: January 29, 1979
    Date of Patent: October 4, 1983
    Assignee: Ludlow Corporation
    Inventor: James McCorkle
  • Patent number: 4401791
    Abstract: A process for the preparation of a modified hydrocarbon resin free of indene. This resin is suitable for use as a binder in a printing ink. It is made from a hydrocarbon resin which is relatively unsuitable for use as a binder in a printing ink.
    Type: Grant
    Filed: May 15, 1979
    Date of Patent: August 30, 1983
    Assignee: Hoechst Aktiengesellschaft
    Inventors: Kurt Hultzsch, Albert Rudolphy
  • Patent number: 4391949
    Abstract: A novel block copolymer having particular utility in adhesive compositions has the structure (A--B).sub.x Y--C).sub.z where A is a poly(monoalkenyl) block, B and C are poly(conjugated diene) polymer blocks, Y is the residue of a multifunctional coupling agent, and x plus z is greater than 6. Also disclosed are adhesive compositions containing such block copolymers.
    Type: Grant
    Filed: November 12, 1981
    Date of Patent: July 5, 1983
    Assignee: Shell Oil Company
    Inventor: David J. St. Clair
  • Patent number: 4374946
    Abstract: A concrete joint sealant comprising tall pitch, atactic polypropylene, fresh rubber and aliphatic hydrocarbon resin.
    Type: Grant
    Filed: September 22, 1981
    Date of Patent: February 22, 1983
    Assignee: Aoi Chemical Inc.
    Inventors: Yoshifumi Takemura, Hirokazu Miyazaki
  • Patent number: 4373041
    Abstract: Tackifying resins, such as rosin esters, hydrogenated rosin esters, and terpene resins, are used as promoters for silica-filled rubber compositions to improve the physical properties, such as tensile, hysteresis, etc., of the rubber.
    Type: Grant
    Filed: October 29, 1981
    Date of Patent: February 8, 1983
    Assignee: Phillips Petroleum Company
    Inventors: Jerold D. Wood, Carl J. Stacy
  • Patent number: 4370433
    Abstract: A highly branched copolymer particularly suitable for forming pressure sensitive adhesives prepared in the presence of specified amounts of tert-butylchloride. Conjugated diene monomers are copolymerized with monovinylaromatic monomers in the presence of an organolithium initiator and a suitable amount of tertiary butylchloride. The holding power of adhesives prepared thereby is greatly increased.
    Type: Grant
    Filed: July 10, 1981
    Date of Patent: January 25, 1983
    Assignee: Phillips Petroleum Company
    Inventors: George M. Allison, III, Mason S. Wilt
  • Patent number: 4359492
    Abstract: Thermoplastic elastomers useful in formulating certain pressure-sensitive hot-melt adhesives are normally very tacky and thus are hard to handle. The present invention relates to a method of eliminating problems due to this tackiness by dusting the elastomer pellets with a friable polymer resin having a ring and ball softening point of at least 95.degree. C. Selection of a polymer resin which is normally used in adhesive formulations allows one to overcome tackiness without having detrimental effects on the ultimate adhesive properties of formulations based on the elastomer.
    Type: Grant
    Filed: March 13, 1981
    Date of Patent: November 16, 1982
    Assignee: Atlantic Richfield Company
    Inventor: James A. Schlademan
  • Patent number: 4340514
    Abstract: A non-toxic liquid stabilizer comprising, (a) from about 5 to about 35 percent of zinc resinate, (b) from about 5 to about 35 percent of calcium resinate, (c) from about 10 to about 40 percent of non-toxic plasticizer, (d) from about 1 to about 10 percent of a non-toxic antioxidant, and (e) from about 25 to about 75 percent of a non-toxic phosphite, said stabilizer containing from about 0.1 to about 3.5 percent zinc, and from about 0.025 to about 2.28 percent calcium, all weights being based upon the total weight of the stabilizer, is disclosed. Also disclosed is a similar stabilizer which does not contain phosphite and contains from about 25 to about 90 percent of the plasticizer. A method for stabilizing halogenated hydrocarbon resins utilizing the stabilizers of the present invention is also disclosed.
    Type: Grant
    Filed: June 29, 1981
    Date of Patent: July 20, 1982
    Assignee: Interstab Chemicals Inc.
    Inventor: David S. Housel
  • Patent number: 4340513
    Abstract: A polyolefin resin composition having superior strength, rigidity, workability, dimensional stability, etc. is provided by blending 0.3 to 4.0% by weight of at least one member selected from rosins, similar materials to rosins, derived therefrom, petroleum resins and mixtures of the foregoing members, 0.5 to 4.0% by weight of a plasticizer and 15 to 60% by weight on dry basis, of finely ground vegetable fibers to a polyolefin resins or resins, all of the above percentages being based on the weight of the composition. Further, 1 to 30% by weight of an inorganic filler and/or 1 to 10% by weight of a synthetic rubber can be blended thereto.
    Type: Grant
    Filed: June 3, 1980
    Date of Patent: July 20, 1982
    Assignees: Chisso Corporation, Kabushiki Kaisha Mikuni Seisakusho
    Inventors: Tsutomu Moteki, Kunihiro Yamaguchi, Yoshikazu Nakajima
  • Patent number: 4340515
    Abstract: The present invention relates to a solid rubber adhesion promoter composition. It comprises 20-90%, preferably 60-80% by weight of cobalt naphthenate, nickel naphthenate or a mixture thereof and 10-80%, preferably 20-40% by weight of cobalt resinate, nickel resinate or a mixture thereof.The composition can be produced in the form of crisp, non-dusting, friable cast solids, powders or flakes. It has a long shelf life and mixes very well into rubber compounds.By the use of the present promoter compositions strong rubber-to-metal adhesion is obtained.
    Type: Grant
    Filed: June 16, 1981
    Date of Patent: July 20, 1982
    Assignee: Akzo NV
    Inventors: Karl-Heinz Frassek, Willy J. van Ooij
  • Patent number: 4336067
    Abstract: A process is provided for producing a pressure-sensitive carbonless record sheet comprising the steps of preparing a hot melt coating composition, the hot melt coating composition being water insoluble and having a melting point of from about 60.degree. C. to about 140.degree. C. The hot melt coating composition includes a chromogenic material. The chromogenic material is a meltable color developer of the acidic electron accepting type. The hot melt coating composition is heated to a temperature above its melting point and the heated coating composition is applied to a substrate, the coating composition being applied at a coat weight of from about 0.2 pounds to about 8.0 pounds per 3300 square feet of substrate. The coating composition is set by cooling the coated substrate. A novel liquid chromogenic coating composition is produced, the coating composition having a melting point of from about 60.degree. C. to about 140.degree. C.
    Type: Grant
    Filed: March 27, 1980
    Date of Patent: June 22, 1982
    Assignee: The Mead Corporation
    Inventors: Dale R. Shackle, Ainslie T. Young, Jr.
  • Patent number: 4325770
    Abstract: A process for making a pressure-sensitive adhesive coated product from an elastomer utilizing dry blending of powders and dry coating steps is described. Compositions suitable for use in this process are also described.
    Type: Grant
    Filed: June 27, 1980
    Date of Patent: April 20, 1982
    Assignee: Permacel
    Inventor: Ralf Korpman
  • Patent number: 4324710
    Abstract: Natural occurring thermoplastic resins are used as a substitute for process oils and/or hydrocarbon resins, as well as for tackifiers, softeners, extenders, processing aids, and cure retarders, in rubber stocks, as for example, a rubber skim stock used in making a tire. The resins, which are derived from crude wood rosin, are high melting thermoplastic resins having carboxylic acid groups and are insoluble in aliphatic hydrocarbons. The source of the natural occurring resins is in ample supply as they are obtained from pine trees grown in North America. A specific type of thermoplastic resin is Vinsol, a registered trademark of Hercules Corporation.
    Type: Grant
    Filed: October 2, 1980
    Date of Patent: April 13, 1982
    Assignee: The Firestone Tire & Rubber Company
    Inventors: James A. Davis, Robert C. Koch
  • Patent number: 4321171
    Abstract: Method and composite of forming an elastomer product which comprises (A) solvent solution polymerizing an olefin monomer in the presence of an organometallic catalyst, (B) shortstopping the reaction with an excess of a rosin acid which has not been submitted to a disproportionation process and (C) recovering the elastomer composite.
    Type: Grant
    Filed: September 18, 1980
    Date of Patent: March 23, 1982
    Assignee: The Goodyear Tire & Rubber Company
    Inventors: James N. Henderson, Paul H. Sandstrom