Toho Chemical Industry Co., Ltd.

Other

Sika Technology Ag

Yoshino Gypsum Co., Ltd.

Sika Corporation

Akira Ikeda

Atsushi Kobayashi

Akira Suga

Seiichi Koshisaka

Kaname Saitoh

Jun Imamura

Wernher M Danzinger

Tetsu Tomoyose

Satoshi Kobayashi

Michael Wernher Danzinger

Katsutoshi Sato

Ikuhide Togami

Hirofumi Bandoh

Susumu Hashizume

Toshihiko Amaya

Kaname Saito

To provide a chemical agent whereby adjustment of air volume is easier, particularly in a hydraulic composition having fly ash blended therein. An admixture for a hydraulic composition, having a structure indicated by general formula (1) and including a carbon blocker including either one type of compound selected from a group comprising phosphate esters or at least two mixtures; and a water-reducing agent. (In the formula, Rindicates a hydrogen atom, an alkyl group, an alkenyl group, or a (meth)acryloyl group, AO indicates a C2-3 oxyalkylene group, n indicates an average added molar number for the oxyalkylene group AO of 2-150, m indicates an integer between 1 and 3, M indicates a hydrogen atom, an alkali metal atom, a group II metal atom, an ammonium group, or an organic ammonium group.)

Admixture for hydraulic composition

There is provided a gypsum dispersant and a gypsum additive that improve the fluidity of gypsum slurry even if gypsum raw materials used are different in quality and that do not induce delay of curing of gypsum slurry. A gypsum dispersant, including: (A) a polycarboxylic acid polymer; and (B) a polymer obtained by a reaction of an alkylene diamine and/or a monoamine and an epihalohydrin as essential components.

Gypsum dispersant

A cement dispersant that includes a copolymer resulting from a reaction of components (A) to (C), where: (A) is an ester compound obtained by adding 0 to 10 moles of Calkylene oxide to 1 mole of at least one compound of Formula (1) RO-(AO)n-H (where R is a Calkyl group, A is a Calkylene group, and n is an integer of 0 to 7) and subjecting the resulting adduct to a reaction with an &#x3b1;,&#x3b2;-unsaturated carboxylic acid, in which the compound of Formula (1) contains not more than 5% by mass of the constituent compounds having n of 3 or less relative to the total mass of the compound of Formula (1); (B) is an &#x3b1;,&#x3b2;-unsaturated carboxylic acid or a salt thereof; and (C) is another copolymerizable monomer, where appropriate, or a salt thereof.

Copolymer and cement dispersant including the copolymer

A superior cement dispersant and a concrete composition containing the cement dispersant, the cement dispersant being a water-soluble amphoteric copolymer which contains an alkylene oxide adduct of a polyamide polyamine having an unsaturated group and at least two types of polyalkylene glycol ester. When the cement dispersant is compounded with a concrete composition, the dispersion performance thereof increases with time, and the concrete viscosity is effectively decreased. The cement dispersant composition contains a water-soluble amphoteric copolymer or the neutralized salt thereof as an essential component, which is obtained by copolymerizing an alkylene oxide adduct of a polyamide polyamine having an unsaturated group, (meta)acrylic acid or an alkali metal, ammonium, or alkanolamine salt thereof, an ester of an alkylene glycol and methacrylic acid, and an ester of an alkylene glycol and acrylic acid. In addition, the concrete composition containing the above cement dispersant is also disclosed.

Cement dispersant and concrete composition containing the dispersant

A cement dispersant (especially a dispersant for concretes with ultrahigh performance) comprising as a main component a water-soluble amphoteric copolymer obtained by copolymerizing (A) a polyamide-polyamine of an alkylene oxide adduct thereof with (B) (meth)acrylic acid or an alkali metal, ammonium, or alkanolamine salt thereof and (C) a polyalkylene glycol ester of (meth)acrylic acid in an A/B/C ratio of (10-40)/(10-40)/(50-80) (wt. %); and a concrete composition (especially an ultral high-performance concrete) containing the dispersant. The dispersant satisfies all of a water-reducing effect, slump flow retention, strength development, etc.

A bottom exhaust type high speed boat has a hull including a grooved bottom. The engine exhaust pipe extends into a midportion of the grooved bottom. A duct fixed to the surface of the hull extends between the opening of the exhaust pipe and the front of the grooved bottom for transporting exhaust gases to the front of the grooved bottom. The grooved bottom is separated into a forward part and a rearward part, having different depths, by a stepped surface. The exhaust opening is on the rearward part whereas the duct is on the forward part. Gas leakage prevention grooves surround the grooved bottom. A triangular projection having dovetail sides extends from the grooved bottom and the engine propeller is positioned on the projection.

Bottom exhaust high speed boat

Growing community of inventors

Sodegaura, Japan

Akira Ikeda