Patents for July 2025
Patents as compiled by the editors of Rubber World Magazine for July 2025.
Silicone rubber composition
U.S. patent: 12,162,986
Issued: December 10, 2024
Inventors: Matsutaka Maeda and Yuji Kitano
Assigned: Canon Kabushiki Kaisha
Key statement: A liquid silicone rubber composition contains metallic silicon particles. The content of the metallic silicon particles is 35% by volume or more and 45% by volume or less. The volume average particle diameter of the metallic silicon particles is 1 μm or more and 20 μm or less. The ratio A/B of viscosity A at a shear rate of 0.02/sec to viscosity B at a shear rate of 1/sec of the composition is 2.0 or less.
Modified conjugated diene based polymer and rubber composition including the same
U.S. patent: 12,162,964
Issued: December 10, 2024
Inventors: Jung Hwan Oh, He Seung Lee, Hyeon Jong Park and Hye Jung Shin
Assigned: LG Chem
Key statement: A modified conjugated diene based polymer and a rubber composition including the same are disclosed herein. The modified conjugated diene based polymer has excellent processability and good tensile strength and viscoelasticity. In some embodiments, a modified conjugated diene based polymer includes a derived unit from a modifier, the modifier including three or more alkoxy groups bonded to silicon, a non-functional chain forming a silicon-carbon bond at one side of the derived unit from a modifier and including a repeating unit derived from a conjugated diene based monomer and a functional chain forming a silicon-carbon bond at the other side of the derived unit from a modifier and including two or more derived units from an N-functional group-containing monomer, wherein the rate of change of Mooney viscosity is 20% or less.
Nitrile rubber condoms and methods of making them
U.S. patent: 12,163,027
Issued: December 10, 2024
Inventors: Fook Peng Leng, Yi Yee Loh and Lai Peng Lim
Assigned: Karex Holdings Sdn. Bhd.
Key statement: This invention provides a method of making an elastomeric article and the method comprises dipping a mold into a first dip tank containing a compounded nitrile rubber formulation to produce an elastomeric film layer on the mold, the compounded nitrile rubber formulation comprising nitrile butadiene copolymer; a crosslinking agent; a metal oxide; a vulcanization accelerator; an antioxidant; an alkali agent; and a heat sensitizer; then drying and curing the elastomeric film layer to form the elastomeric article. The heat sensitizer may be an organopolysiloxane. Elastomeric articles prepared according to this invention may have a film thickness in a range of 0.020 mm to 0.050 mm; such films are suitable for medical examination gloves, surgical gloves or condoms.
Additive manufacturing method for producing a silicone elastomer item
U.S. patent: 12,162,213
Issued: December 10, 2024
Inventors: Mickael Muller, Jean-Marc Frances, Perrine Theil and Geoffray Meffre
Assigned: Elkem Silicones
Key statement: The invention relates to an additive manufacturing process for producing a silicone elastomer item. In particular, the invention relates to an additive manufacturing method for producing a silicone elastomer item from a photocrosslinkable silicone composition. The invention also relates to a photocrosslinkable silicone composition.
Method of recycling tires
U.S. patent: 12,162,191
Issued: December 10, 2024
Inventor: Mark Molloy
Key statement: A method of recycling tires places tires and/or pieces of tires within a casing or mold. A binder (e.g., adhesives and/or pining with screws, nails, nuts and bolts, pins, wire and steel or nylon bands, etc.) is applied to the tires and/or pieces of tires so that the tires are bound together. A reinforcing means is applied to the tires and/or pieces of tires (e.g., fitting the reinforcing means around, in between and/or through the tires, etc.). An encapsulating means is melted and poured over the top of the tires and reinforcing means to encapsulate them inside the casing or mold and the encapsulating means. The encapsulating means is allowed to set such that a recycled product is formed.
Resin rubber composite, tire and method of producing resin rubber composite
U.S. patent: 12,163,028
Issued: December 10, 2024
Inventors: Hiroyuki Fudemoto, Atsushi Fukushima, Masahiro Homma, Yuji Ohkubo and Kazuya Yamamura
Assigned: Bridgestone and Osaka University
Key statement: A resin-rubber composite includes: a resin member that has a treated surface, to which a surface treatment by means of a plasma treatment has been applied; and a rubber member that is disposed in contact with the treated surface of the resin member and includes a rubber, a filler having a silanol group and a silane coupling agent, with a filler content of from 30 phr to 100 phr with respect to 100 phr of the rubber and a silane coupling agent content of from 2 parts by mass to 15 parts by mass with respect to 100 parts by mass of the filler.
Acrylic rubber, acrylic rubber composition, crosslinked acrylic rubber, seal material and hose material
U.S. patent: 12,162,969
Issued: December 10, 2024
Inventors: Fumiaki Bando and Susumu Sato
Assigned: Zeon
Key statement: An acrylic rubber containing acrylate monomer units, methacrylate monomer units and crosslinkable monomer units, wherein a glass transition temperature is -20°C or less, a change ratio in volume after a crosslinked rubber of the acrylic rubber is immersed in IRM903 oil at 150 ± 2°C for 72 hours is 0 to 100% and a change ratio in weight after a crosslinked rubber of the acrylic rubber is immersed in hot water at 150 ± 2°C for 96 hours and dried is -5.0 to 0%
Process for producing polyurethane-polyisocyanurate elastomers, sealing materials and adhesives having a long pot life
U.S. patent: 12,162,973
Issued: December 10, 2024
Inventors: Julia Liese, Andre Kamm and Hendrik Wagner
Assigned: BASF SE
Key statement: Described herein is a process for preparing a polyurethane elastomer including the steps of (A) preparing an isocyanate prepolymer (a), where the isocyanate prepolymer has an isocyanate content in the range of ≥ 1 wt.% to ≤ 9 wt.% and (B) preparing a reaction mixture by mixing at least one epoxy compound (b) with the isocyanate prepolymer (a) in presence of at least one catalyst (c) and where the amount of the alkali metal or alkaline earth metal salt is 0.00001 to 0.1 mol per kg of the total weight of the isocyanate prepolymer (a), the epoxy compound (b) and the catalyst (c) and heating the mixture to at least 80°C to obtain the polyurethane elastomer. Also described herein are a polyurethane elastomer obtained by the process and a method of using the polyurethane elastomer as part of a roller or as a sealant.
Polymer coated sulfur cured rubber composition
U.S. patent: 12,163,059
Issued: December 10, 2024
Inventors: Philip Roberts, Adam Donley and Paul Cannon
Assigned: Sublino
Key statement: There is disclosed a method of forming a polymer coated sulfur cured rubber composition wherein the bond strength between the polymer coating and the sulfur cured rubber is surprisingly great. The method includes providing a sulfur curable rubber composition comprising a compound including at least one thiol group and/or contacting a sulfur curable rubber composition with a compound including at least one thiol group and contacting the sulfur curable composition with a second polymeric precursor including a diallylamide group. The compound including at least one thiol group and the second polymeric precursors are reacted together to form a polymeric layer; and the sulfur curable rubber composition is cured to form a polymer coated sulfur cured rubber composition.
Pneumatic tire
U.S. patent: 12,168,371
Issued: December 17, 2024
Inventors: Momoka Misaki, Dong Miao and Hiroki Kawai
Assigned: Sumitomo Rubber Industries
Key statement: To provide pneumatic tires with excellent ride quality during high-speed driving, a pneumatic tire having a tread portion with a circumferential groove and a belt layer, wherein a monofilament cord is used as a reinforcing cord for the belt layer; and the number of arrangements e (lines/5 cm) of the monofilament cords per 5 cm in the tire width direction in the tire radial cross section of the belt layer, the distance G (mm) from the surface of the land portion closest to the equatorial plane among land portions separated by the circumferential groove to the monofilament cord and the loss tangent (30°C tan δ) when the rubber composition constituting the surface of the tread portion is measured satisfy (30°C tan δ×G)/e>0.015 is provided.
Rubber composition and molded article manufactured therefrom
U.S. patent: 12,168,710
Issued: December 17, 2024
Inventors: Youk Reol Na, Jin Young Kim, Jae Sun Choi and No Ma Kim
Assigned: LG Chem
Key statement: A rubber composition having excellent abrasion resistance and improved viscoelasticity properties and a tire manufactured using the same are disclosed herein. In some embodiments, a rubber composition includes a first synthetic rubber and a second synthetic rubber and has an interaction parameter (χblend) defined by Mathematical Formula 1 at room temperature is 2.0×10-3 or more. The first synthetic rubber is a solution-polymerized modified conjugated diene based rubber which has a 1,2-vinyl bond content of 50 wt.% or more and includes a functional group bonded to at least one terminal and the second synthetic rubber is a conjugated diene based rubber which has a 1,2-vinyl bond content of less than 50 wt.%.
Modified high cis polydiene polymer, related methods and rubber compositions
U.S. patent: 12,168,705
Issued: December 17, 2024
Inventors: Zengquan Qin and Yuan-Yong Yan
Assigned: Bridgestone
Key statement: Disclosed herein are a modified high cis polydiene polymer, processes for preparing the modified high cis polydiene polymer and tire rubber compositions containing the modified high cis polydiene polymer. The processes make use of a functionalizing compound of formula I or formula II and a coupling agent to prepare the modified high cis polydiene polymer from a quantity of conjugated diene monomer polymerized using a lanthanide based catalyst system. The modified high cis polydiene polymer includes at least one polymer chain having a residue from the functionalizing compound and a residue from the coupling agent and can be utilized in tire rubber compositions in combination with other ingredients such as fillers.
Functional diene elastomer and rubber composition
U.S. patent: 12,168,708
Issued: December 17, 2024
Inventors: Emma Moreso, Kahina Mammeri and Anne-Frédérique Salit
Assigned: Michelin
Key statement: A diene elastomer and a rubber composition comprising the diene elastomer is provided. The diene elastomer bears pendent imidazole functions in a molar content of at most 4% of the constituent repeating units of the diene elastomer, which diene elastomer is a copolymer of ethylene and of a 1,3-diene comprising ethylene units, the ethylene units representing at least 50 mol % of the constituent repeating units of the diene elastomer, the 1,3-diene being 1,3-butadiene or isoprene. Such an elastomer confers improved uncured properties on the rubber composition.
Silicone rubber molded body and production method for the same
U.S. patent: 12,168,724
Issued: December 17, 2024
Inventors: Hiroaki Yasuda, Takehiro Hamamura, Susumu Yonezawa, Jae-Ho Kim, Fumihiro Nishimura, Mitsuo Kurumaya, Takeshi Kamiya and Tsunetoshi Honda
Assigned: Mitsubishi Cable Industries
Key statement: A silicone rubber molded body (10) has an article contact surface (11). The article contact surface (11) has a coefficient of rolling resistance lowered by a fluorination treatment on the article contact surface (11).
Rubber Composition and Pneumatic Tire
U.S. patent: 12,173,140
Issued: December 24, 2024
Inventors: Ryota Kitago, Rie Yasuda and Hirao
Assigned: Sumitomo Rubber
Key statement: The purpose is to provide rubber compositions and pneumatic tires which have reduced changes in complex modulus E* over time. The present invention relates to rubber compositions containing at least one copolymer obtained by copolymerizing an aromatic vinyl compound and a conjugated diene compound, the rubber compositions having a heat aging resistance index defined by equation (1) of 27 or less.
Rubber Composition and Conveyor Belt Using the Same
U.S. patent: 12,173,144
Issued: December 24, 2024
Inventors: Tao Xu, Zhi Sheng Fu and An Yang Wu
Assigned: Hangzhou Xinglu Technologies and Shaoxing Pinghe New Material Technology Key statement: The present invention discloses a rubber composition comprising, in parts by weight, 100 parts of a rubber matrix, 1.5 to 9 parts of a crosslinking agent, 0.2 to 9 parts of an assistant crosslinking agent, 40 to 170 parts of a reinforcing filler, 6 to 93 parts of a plasticizer and 3 to 25 parts of a metal oxide. The rubber matrix comprises a branched polyethylene with a content represented as A, in which 0<A≤100 parts, an EPM with a content represented as B, in which 0≤B<100 parts, and an EPDM with a content represented as C, in which 0≤C<100 parts. The present invention provides a rubber composition which is excellent in heat resistance and mechanical properties and is useful in a cover rubber of a conveyor belt.