Sumitomo Rubber Industries Limited

Ichiro Tominaga

Teruo Sasaki

Akihiro Nakahara

Taketo Matsuki

Mikio Yamada

Tsuneyuki Nagase

Tetsuo Yamaguchi

Kunio Niwa

Takefumi Nakashita

Hiroomi Matsushita

Atsuko Mitsuba

Daijiro Touji

Yukiyasu Nakashio

Masao Nakamura

Disclosed is a structural material excelling in lightness of weight, strength, flexural modulus and other properties, being made from polyamide resin reinforced with continuous fiber and/or long filament reinforcing material. This structural material can be fabricated by a monomer casting method by arranging said fiber reinforcing material preliminarily in a desired shape, putting it into a mold, pouring molten &ohgr;-lactams containing a polymerization catalyst and an initiator into said mold, and heating to obtain polyamide resin.

Structural material and process for its production

A tennis ball having a felt covering which has superior abrasion resistance, felt appearance and resistance to fuzzing which may occur during the use of ball, the felt covering being made of a polyethylene terephthalate fiber including a polyethylene terephthalate (PET) polymer containing at least 90 mole % of recurring ethylene terephthalate units which satisfies the following parameters:

Tennis ball

Low-temperature insulating material

An iron type golf club head comprising a composite material of light metal or synthetic resin containing silicon carbide whiskers at 2 to 80% by volume and occupying 20% or more by volume of the body of the club head. The club head can be 10 to 60% lighter than a club head made entirely of steel with the same configuration and size, while the moment of inertia is approximately the same. Weight metal inserts having a specific gravity greater than steel can also be embedded in the club head.

Iron type golf club head

A cover composition for golf balls having an improved impact resistance which comprises an ionomer resin and 1 to 15 parts by weight of a linear low density polyethylene per 100 parts by weight of the ionomer resin.

Composition for cover of golf balls

A zinc acrylate powder coated with a higher fatty acid has a good dispersibility into a rubber, and is used as a co-crosslinking agent in rubber compositions for one piece solid golf balls or for cores of covered solid golf balls. The compositions containing the coated zinc acrylate have a good roll workability and provide solid golf balls having an improved impact resilience, a proper hardness and good sound and feeling of striking.

Golf ball

The present invention provides solid golf balls having excellent rebound performance, durability and flight carry characteristics produced from a rubber composition containing one or more agents for regulating the molecular weight of grafted chain selected from the group consisting of 2-(4-morpholinyldithio) benzothiazole, 4,4'-dithio-bis-dimorpholine, dipentamethylenethiuram tetrasulfide and derivatives thereof.

Solid golf balls

A method for measuring the physical properties of material comprising the steps of producing a tone burst wave by a tone burst wave oscillator, radiating acoustic energy of the tone burst wave onto an object to be measured to cause vibrations therein, detecting the vibrations as a waveform of an alternating wave at a vibration receiver, obtaining a gradient of a line which connects peaks in a first transitional region of the waveform from which can be determined the physical properties, in particular the energy transfer characteristics and/or restitution coefficient of the object.

Method for measuring physical properties of material

A solid golf ball is prepared using a rubber composition comprising a microencapsulated zinc salt of allyl group containing carboxylic acid, which is uniformly blended into a rubber to bring an excellent impact resilience in the golf ball. Further, the rubber composition comprising the microencapsulated zinc salt has little tendency to stick to a roll at the kneading of the rubber composition.

Process for preparing a solid golf ball

A method of discriminating solid golf balls from thread-wound golf balls which includes the steps of holding the golf ball to be discriminated between a transmitter coupled to an ultrasonic wave oscillator and a receiver coupled to an ultrasonic detector for detecting the ultrasonic wave received by the receiver, applying from the transmitter, the ultrasonic wave having a frequency which can propagate through the solid golf ball, but can not propagate therethrough, to the golf ball to be discriminated, and detecting presence of the ultrasonic wave reaching the receiver through the golf ball to be discriminated by the ultrasonic wave detector.

Method of discriminating kinds of golf balls

A method of measuring hardness of a flexible thread-wound golf ball or its inner core which includes the steps of holding the flexible thread-wound golf ball or its inner core to be measured between a transmitter coupled to an ultrasonic wave oscillating source and a receiver coupled to an ultrasonic wave detecting device which detects the ultrasonic wave received by said receiver, applying from the transmitter, the ultrasonic wave having predetermined frequency to the flexible thread-wound golf ball or its inner core, and measuring the hardness of the flexible thread-wound golf ball or its inner core selectively by or based on the propagation time of the ultrasonic wave passing through the central portion of the flexible thread-wound golf ball or its inner core.

Method of measuring hardness of flexible thread-wound golf balls or

This invention is directed to a composition for use as a material for the outer layer of a golf ball, which composition is produced by the reaction of an ionomer resin with a monoepoxy compound. The golf ball having the outer layer of such composition can be driven for a long distance with a soft shot feeling.

Growing community of inventors

Kobe, Japan

Ichiro Tominaga