Abstract: The cement admixture of the present invention can improve the workability by displaying sufficient viscosity decreasing ability and initial dispersing ability even under a low temperature environment as well as high dispersing ability and dispersion retaining ability even in a high water reducing ratio range. The above-mentioned cement admixture comprises four components of a copolymer (A) containing a constituent unit (I) derived from the unsaturated (poly)alkylene glycol ether monomer (a) and a constituent unit (II) derived from a maleic acid monomer (b), a specific unsaturated (poly)alkylene glycol ether monomer (a), a non-polymerizable (poly)alkylene glycol (B) having no alkenyl group, and a polymer (C) having an oxyalkylene group or a polyoxyalkylene group and a carboxyl group, which is different from the copolymer (A).

Abstract: The cement admixture of the present invention can provide viscosity decreasing ability as well as a high dispersing ability and slump loss preventing ability even in a high water reducing ratio range. The above-mentioned cement admixture comprises three components of a copolymer (A) containing a constituent unit (I) derived from the unsaturated (poly)alkylene glycol ether monomer (a) and a constituent unit (II) derived from a maleic acid monomer (b), a specific unsaturated (poly)alkylene glycol ether monomer (a) and a non-polymerizable (poly)alkylene glycol (B) having no alkenyl group.

Abstract: An electromagnetic-wave absorbing method using a solar cell or cells is provided, whereby there comes about essentially no reflection of electromagnetic waves by the solar cell or cells without impeding solar light power generation thereby. A solar cell module (10) may be constructed from a plurality of solar cells (1) wherein respective upper electrodes (2, 2) are electrically connected together by a conductor (7) and a common lower electrode (6) is used. So that any possibly reflected wave may be absorbed, the impedance of the solar cells to electromagnetic waves incident thereon is matched to an electromagnetic-wave characteristic impedance by adjusting the number of the solar cells (1) arranged or the way in which they are arranged or by connecting a capacitor (13) across a pair of output terminals (8, 9) of the module.

Abstract: The present invention provides: a copolymer for cement admixtures which displays high dispersibility with a small adding amount and excellent dispersibility particularly even in a high water reducing ratio area, a cement admixture utilizing the copolymer, and a cement composition, and further, a production process for the copolymer. The copolymer for cement admixtures comprises: constitutional unit (I) derived from unsaturated polyalkylene glycol ether monomer (a) having an alkenyl group having 5 carbon atoms and an oxyalkylene group having 2 to 18 carbon atoms with an average addition number of moles of the oxyalkylene groups to be in the range of 10 to 300; and constitutional unit (II) derived from unsaturated monocarboxylic acid monomer (b). The cement admixture includes the copolymer for cement admixtures as an essential component, and may further include a defoaming agent. The cement composition includes the copolymer for cement admixtures, and cement as essential components.

Abstract: It is an object of the present invention to provide a cement admixture capable of exhibiting high cement dispersing ability at low addition levels, in particular capable of displaying excellent initial dispersing ability and dispersion retaining ability even in a high water reducing ratio range, and a cement composition in which this admixture is used.

Abstract: The present invention is to provide a production method of chemical reactive substances with stable quality by which solidification, gel formation, and the resulting blockade within material injection nozzles are prevented, and contamination of a reaction system with the gelled matter is prevented, as well as occurrence of problems on a production process due to the gelled matter is suppressed, when the chemical reactive substances are produced by injecting the liquid materials containing reactive substances having unsaturated double bonds into the reaction vessel through the material injection nozzles of the reaction vessel.

Abstract: The present invention provides: a copolymer for cement admixtures which displays high dispersibility with a small adding amount and excellent dispersibility particularly even in a high water reducing ratio area, a cement admixture utilizing the copolymer, and a cement composition, and further, a production process for the copolymer. The copolymer for cement admixtures comprises: constitutional unit (I) derived from unsaturated polyalkylene glycol ether monomer (a) having an alkenyl group having 5 carbon atoms and an oxyalkylene group having 2 to 18 carbon atoms with an average addition number of moles of the oxyalkylene groups to be in the range of 10 to 300; and constitutional unit (II) derived from unsaturated monocarboxylic acid monomer (b). The cement admixture includes the copolymer for cement admixtures as an essential component, and may further include a defoaming agent. The cement composition includes the copolymer for cement admixtures, and cement as essential components.

Abstract: It is an object of the present invention to provide a cement admixture which can show not only a high dispersing ability and a slump loss preventing effect but also a viscosity reducing effect and can show these characteristics even in the high water reduction ratio range, and a cement composition in which this admixture is used.

Abstract: A cement dispersant which displays high dispersibility with a small addition amount and excellent dispersibility particularly even in a high water-reducing ratio area, and a cement composition comprising this. A first cement dispersant includes a copolymer having a first constitutional unit derived from an unsaturated (poly)alkylene glycol ether monomer; and a second constitutional unit derived from an unsaturated monocarboxylic acid monomer, wherein the second constitutional unit includes at least one structure derived from an acrylic acid (salt).

Abstract: It is an object of the present invention to provide a polycarboxylic acid copolymer which improves the water reducing capacity and workability of cement compositions and the like and making them easier to handle when the fluidity and water reducing capacity are at the same levels, a method of producing the copolymer, and a cement additive and a cement composition comprising the copolymer. The present invention is further to provide a polycarboxylic acid copolymer and a cement additive which are capable of improving the strength and durability of hardening products of cement compositions, hence can advantageously be used in ultrahigh strength concrete. The present invention is still further to provide a method of producing polycarboxylic acid copolymers having high water reducing capacity, reducing the viscosity of cement compositions and improving the workability in applying cement.

Abstract: It is an object of the present invention to provide a production method of a dehydration reaction product by which the occurrence of troubles in the production step or the degradation in performance characteristics or quality of various chemical products can be suppressed to a satisfactory extent.

Abstract: The present invention provides: a cement dispersant which displays high dispersibility with a small addition amount and excellent dispersibility particularly even in a high water-reducing ratio area, and a cement composition comprising this.

Abstract: A cement dispersant having excellent ability to prevent slump loss and high water-reducing property which comprises a polycarboxylic acid type polymer having a specific molecular weight distribution, a method for the production thereof, and a cement composition using the dispersant are provided. The cement dispersant comprises as a main component thereof a polycarboxylic acid type polymer (A), having a weight average molecular weight in the range of 10,000 to 500,000 in terms of polyethylene glycol determined by gel permeation chromatography, and having a value determined by subtracting the peak top molecular weight from the weight average molecular weight in the range of 0 to 8,000.

Abstract: A cement dispersant having excellent ability to prevent slump loss and high water-reducing property which comprises a polycarboxylic acid type polymer having a specific molecular weight distribution, a method for the production thereof, and a cement composition using the dispersant are provided. The cement dispersant comprises as a main component thereof a polycarboxylic acid type polymer (A), having a weight average molecular weight in the range of 10,000 to 500,000 in terms of polyethylene glycol determined by gel permeation chromatography, and having a value determined by subtracting the peak top molecular weight from the weight average molecular weight in the range of 0 to 8,000.

Abstract: A cement composition excelling in the slump retaining property which comprises at least cement admixture comprising as a main ingredient thereof (I) a copolymer (A) of short-chain polyalkylene glycol (meth)acrylate (a), a long-chain polyalkylene glycol (meth)acrylate (b), a carboxylic acid monomer (c), and a monomer copolymerizable with the monomers mentioned above or a salt of the copolymer (B), (II) a copolymer (A.sub.1) of the monomers (a), (c), and (d) mentioned above or a salt thereof, (III) a mixture of a copolymer (A.sub.1) of the monomers (a), (c), and (d) mentioned above or a salt (B.sub.1) of thereof with a known cement admixture, or (IV) a polycarboxylic acid based polymer (A.sub.3) manifesting to a calcium sulfoaluminate based expansive additive an adsorption ratio of not less than 90% in 5 minutes at room temperature when added in an amount of 0.1% by weight as solids or a salt (B.sub.

Abstract: A swellable oil-absorbent agent formed of a cross-linked polymer (P) obtained by polymerizing a monomer component comprising 90 to 99.999% by weight of a monomer having as a main moiety thereof an alkyl (meth)acrylate the alkyl group of which has 10 to 16 carbon atoms and possessing one polymerizable unsaturated group in the molecular unit thereof and 0.001 to 10% by weight of a cross-linkable monomer possessing at least two polymerizable unsaturated groups in the molecular unit thereof (providing that the total of the amount of the polymerizable monomer and that of the cross-linkable monomer is 100% by weight).

Abstract: A swellable oil-absorbent agent formed of cross-linked polymer (P) obtained by polymerizing a monomer component comprising 90 to 99.999% by weight of a monomer having as a main moiety thereof an alkyl (meth)acrylate the alkyl group of which has 10 to 16 carbon atoms and possessing one polymerizable unsaturated group in the molecular unit thereof and 0.001 to 10% by weight of a cross-linkable monomer possessing at least two polymerizable unsaturated groups in the molecular unit thereof (providing that the total of the amount of the polymerizable monomer and that of the cross-linkable monomer is 100% by weight).

Abstract: A resin composition for a composite-type vibration-damping material which comprises a saturated copolyester having a weight average molecular weight of at least 10,000 and a softening point of 50.degree. to 150.degree. C. and a polyfunctional isocyanate compound as a cross-linking agent and which, when cross-linked, has a degree of gelation (degree of cross-linking) of at least 10% and a composite-type vibration-damping material produced by use of the resin composition, have excellent adhesive strength and formability.When the resin composition is admixed with a conductive substance, a vibration-damping material produced by use of the admixture has excellent spot-weldability in addition to the above-mentioned excellent properties.

Abstract: An electronic card receiving device includes a card holder forming a card receiving space in the device for receiving an electronic card, a card latching mechanism for holding the electronic card in position in the card receiving space formed by the card holder, a contacting mechanism for electrically connecting the device to contacts of the electronic card held in position, and a card pushing mechanism for disconnecting the device from the electronic card and pushing it out of the device. The card pushing mechanism comprises a first ejecting plate and a second ejecting plate slidable in directions of inserting and removing the electronic card. The first ejecting plate comprises an abutting portion for applying a force to an inserted electronic card to push it in the direction of removing the card.