The Dow Chemical Company

Asahi Kasei Kogyo Kabushiki Kaisha

Asahi-dow Limited

Norio Onofusa

Kazuhiko Hiyoshi

Tadao Nishikage

Norio Matsuura

Michiharu Matsuguchi

Toshiaki Yamazaki

Michiharu Matsugichi

The present invention aims to provide a cover for accommodating an air bag, having a high opening reliability, adaptable to a wide range of temperatures, having a good durability and a suitable touch, and providing a high productivity and a lower cost, and reducing the weight of the air bag apparatus as a whole. To attain the above object, the cover of the present invention is injection molded from a thermoplastic elastomer comprised of the following components (a), (b), (c) and (d), and having a hardness of between 60 and 85 measured according to JIS K 6301 TypeA. (a) a hydrogenated styrene and conjugated diene block copolymer of between 30 parts by weight and 55 parts by weight and obtained by hydrogenating a block copolymer composed of at least two polymer blocks including styrene units as a main part thereof and at least one polymer block including conjugated diene units as a main part thereof, a content of the styrene in the copolymer being between 20% by weight of the copolymer being 10.sup.5 or more; (b) a plasticizer to be used for a rubber, at between 25 parts by weight and 50 parts by weight; (c) an olefin group resin, at between 15 parts by weight and 30 parts by weight; (d) an additive of 5 parts by weight or less; wherein (a)+(b)+(c)=100 parts by weight.

Cover for accommodating air bag in air bag system

An aqueous dispersion of vinylidene chloride resin which, when coated onto a synthetic resinous film substrate, has the combined properties of: (1) good adhesion to the substrate; (2) good adhesion of a printing ink to the coating; (3) satisfactory barrier to gases (especially oxygen) and water vapor; and (4) a high resistance to boiling water treatment. The vinylidene chloride resin must also have polymerized therein methyl methacrylate, methacrylonitrile and methacrylic acid. A total amount of methacrylic acid must be between 1.times.10.sup.-4 and 3.times.10.sup.-4 moles of methacrylic acid per gram of polymer solids. A portion of the total amount of methacrylic acid exists in a form titratable with a 1/20 Normal aqueous solution of sodium hydroxide. The portion must be the less of (a) about 1.3.times.10.sup.-4 moles per gram of polymer solids or (b) about 60 percent of the total amount.

Aqueous dispersions of vinylidene chloride resins

An aqueous dispersion of a vinylidene chloride resin which, when coated onto a synthetic resinous film substrate, has the combined properties of: (1) good adhesion to the substrate; (2) good adhesion of a printing ink to the coating; (3) satisfactory barrier to gases (especially oxygen) and water vapor; and (4) a high resistance to a boiling water treatment. The dispersion must also contain an unsaturated carboxylic acid in an amount of from about 0.5.times.10.sup.-4 to about 4.times.10.sup.-4 mol of unsaturated carboxylic acid units per gram of solids in the dispersion. The unsaturated carboxylic acid must have a partition coefficient of greater than or equal to 1. A limited portion of the amount of the unsaturated carboxylic acid is contained in the aqueous phase. The remaining unsaturated carboxylic acid is polymerized with the vinylidene chloride.

An aqueous dispersion of a vinylidene chloride copolymer resin which, when coated onto a synthetic resinous film substrate, has the combined properties of: (1) good adhesion to the substrate; (2) good adhesion of a printing ink to the coating; (3) excellent barrier to gases (especially oxygen) and water vapor; and (4) a high resistance to a boiling water treatment. The dispersion must contain methacrylic acid in an amount of from about 1.times.10.sup.-4 to about 3.times.10.sup.-4 moles per gram of polymer solids content. The dispersion must also have a molar ratio of acrylonitrile to methyl methacrylate of from about 0 to 1 to about 1 to 1. A limited portion of the amount of methacrylic acid is contained in the aqueous phase. The remaining amount of methacrylic acid is polymerized with the vinylidene chloride.

Growing community of inventors

Yokohama, Japan

Norio Onofusa