Abstract: A task of the present invention is to obtain an aqueous polyurethane resin dispersion which is advantageous not only in that the dispersion exhibits excellent storage stability in an aqueous medium, but also in that after the dispersion is dried, a film having satisfactory flexibility is formed. In the present invention, there is provided an aqueous polyurethane resin dispersion comprising a polyurethane resin dispersed in an aqueous medium, wherein the polyurethane resin is obtained by reacting (A) a polyurethane prepolymer with (B) a chain extender, wherein the polyurethane prepolymer (A) is obtained by reacting (a) a polycarbonate polyol compound, (b) a polyisocyanate compound, (c) an acid group-containing polyol compound, and (d) a compound having one acid group and one hydroxyl group, wherein the chain extender (B) contains (B-1) a polyamine compound having three or more amino group(s) and/or imino group(s) in total.

Abstract: The present invention is to provide an aqueous polyurethane resin dispersion in which a polyurethane resin s dispersed in an aqueous medium, wherein the polyurethane resin is obtained by reacting (A) a polyurethane prepolymer which is obtained by reacting (a) a polyisocyanate compound, (b) a polyol compound containing a polycarbonate polyol having a number average molecular weight of 800 to 3500, and (c) an acidic group-containing polyol compound, and (B) a chain extender, being dispersed in an aqueous medium, (B) the chain extender contains a polyamine compound having three or more in total of an amino group(s) and/or an imino group(s) per molecule, and the polyurethane resin has, each based on a solid content, a content of urethane bonds of 5 to 10% by weight, a content of urea bonds of 2 to 7% by weight, a content of carbonate bonds of 15 to 40% by weight, has neither ether bond nor ester bond, has a density of cross-linking points of 1.0×10?4 to 1.

Abstract: An aqueous polyurethane resin dispersion containing a polyurethane resin obtained by reacting (A) a polyurethane prepolymer obtained by reacting (a) a polyisocyanate compound, (b) at least one polyol compound containing a polycarbonate polyol having a number average molecular weight of 400 to 3000, (c) an acidic group-containing polyol compound, (d) a blocking agent for an isocyanate group, which dissociates at 80 to 180° C., and (B) a chain elongating agent having reactivity with the isocyanate group, being dispersed in an aqueous medium, a sum of a content of urethane and urea bondings is 15 to 30% by weight in terms of solid components, a content of carbonate bondings is 8% to <15% by weight in terms of solid components, and a content of isocyanate group to which the above-mentioned blocking agent has bound is 0.2 to 3% by weight in terms of solid components as calculated on isocyanate group.

Abstract: An aqueous polyurethane resin dispersion containing a polyurethane resin obtained by reacting (A) a polyurethane prepolymer obtained by reacting (a) a polyisocyanate compound, (b) at least one polyol compound containing a polycarbonate polyol having a number average molecular weight of 400 to 3000, (c) an acidic group-containing polyol compound, and (d) a blocking agent for an isocyanate group, which dissociates at 80 to 180° C., and (B) a chain elongating agent having reactivity with the isocyanate group, being dispersed in an aqueous medium, a sum of a content of urethane bondings and a content of urea bondings is 7 to 18% by weight of solid components, a content of carbonate bondings is 15 to 40% by weight of solid components, and a content of an isocyanate group to which the above-mentioned blocking agent has bonded is 0.2 to 3% by weight of solid components and calculated on the isocyanate group.

Abstract: The present invention is to provide an aqueous polyurethane resin dispersion in which a polyurethane resin s dispersed in an aqueous medium, wherein the polyurethane resin is obtained by reacting (A) a polyurethane prepolymer which is obtained by reacting (a) a polyisocyanate compound, (b) a polyol compound containing a polycarbonate polyol having a number average molecular weight of 800 to 3500, and (c) an acidic group-containing polyol compound, and (B) a chain extender, being dispersed in an aqueous medium, (B) the chain extender contains a polyamine compound having three or more in total of an amino group(s) and/or an imino group(s) per molecule, and the polyurethane resin has, each based on a solid content, a content of urethane bonds of 5 to 10% by weight, a content of urea bonds of 2 to 7% by weight, a content of carbonate bonds of 15 to 40% by weight, has neither ether bond nor ester bond, has a density of cross-linking points of 1.0×10?4 to 1.

Abstract: An aqueous polyurethane resin dispersion exhibits excellent drying properties of coating films and gives coating films having high water resistance and on the other hand showing a high rate of swelling with respect to aqueous cleaning liquids to permit new application. The aqueous polyurethane resin dispersion is a dispersion of a polyurethane resin in an aqueous medium, the polyurethane resin being obtained by reacting (A) a polyurethane prepolymer obtained from (a) a polyisocyanate compound, (b) a polycarbonate polyol with a number average molecular weight of 400 to 3000, (c) an acidic group-containing polyol compound and (d) a blocking agent, with (B) a chain extender, the total content of urethane bonds and urea bonds being 7 to 15 wt %, the content of carbonate bonds being 15 to 40 wt %, the content of ether bonds being 0 wt %, the content of isocyanate groups bonded to the blocking agent being 0.

Abstract: An aqueous polyurethane resin dispersion is a dispersion of a polyurethane resin in an aqueous medium, the polyurethane resin being obtained by reacting (A) a polyurethane prepolymer obtained by reacting (a) a polyisocyanate compound, (b) a polyol compound including a polycarbonate polyol with a number average molecular weight of 400 to 3000, (c) an acidic group-containing polyol compound and (d) a blocking agent, with (B) a chain extender, the total content of urethane bonds and urea bonds being 7 to 15 wt %, the content of carbonate bonds being 15 to 40 wt %, the content of ether bonds being 0.5 to 5 wt %, the content of isocyanate groups bonded to the blocking agent being 0.2 to 2.0 wt %, each of these contents being based on solid contents, the acid value being 10 to 16 mg KOH/g. The aqueous polyurethane resin dispersion can form coating films which permit new application while exhibiting excellent water resistance and solvent resistance. A coating composition includes the dispersion.

Abstract: Disclosed is an aqueous polyurethane resin dispersion which comprises a polyurethane resin which is obtained by reacting (A) a polyurethane prepolymer obtained by reacting (a) a polycarbonate polyol having an alicyclic structure in the main chain, (b) an acidic group-containing polyol compound and (d) a polyisocyanate, and (B) a chain-elongating agent, being dispersed in an aqueous medium, a carboxylic acid group content of the above-mentioned (A) polyurethane prepolymer based on a solid component of (A) the polyurethane prepolymer is 2.0 to 13.0% by weight, and a number of a hydroxyl equivalent of a mixture of the above-mentioned (a) polycarbonate polyol having an alicyclic structure in the main chain, the above-mentioned (b) acidic group-containing polyol compound, and, if necessary, (c) a polyol other than (a) and (b) is 70 to 270.

Abstract: An aqueous polyurethane resin dispersion which can easily carry out repaint or removal of an extra coating film after coating on a substrate material is to be provided. It is an aqueous polyurethane resin dispersion which comprises a polyurethane resin obtained by reacting (A) a polyurethane prepolymer which is obtained by reacting (a) a polyisocyanate compound, (b) at least one polyol compound containing a poly-carbonate polyol having a number average molecular weight of 400 to 3000, (c) an acidic group-containing polyol compound, and (d) a blocking agent for an isocyanate group, which dissociates at 80 to 180° C.

Abstract: An aqueous polyurethane resin dispersion which can easily carry out repaint or removal of an extra coating film after coating on a substrate material, and has high coating film hardness is to be provided. It is an aqueous polyurethane resin dispersion which comprises (A) a polyurethane resin obtained by reacting (a) a polyisocyanate compound, (b) at least one polyol compound containing a polycarbonate polyol having a number average molecular weight of 400 to 3000, (c) an acidic group-containing polyol compound, and (d) a blocking agent for an isocyanate group, which dissociates at 80 to 180° C.

Abstract: An aqueous polyurethane resin dispersion which can provide a coating film having high impact resistance and hardness and excellent in adhesiveness to an electrodeposited coating surface is to be provided. It is an aqueous polyurethane resin dispersion which comprises a polyurethane resin obtained by reacting (A) a polyurethane prepolymer which is obtained by reacting (a) a polyisocyanate compound, (b) at least one polyol compound containing a polycarbonate polyol having a number average molecular weight of 400 to 3000, (c) an acidic group-containing polyol compound, and (d) a blocking agent for an isocyanate group, which dissociates at 80 to 180° C.

Abstract: It is to provide an aqueous polyurethane dispersion which gives a coating film excellent in abrasion resistance. It is an aqueous polyurethane resin dispersion which comprises a polyurethane resin obtained by reacting (A) a polyurethane prepolymer which is obtained by reacting (a) a polyisocyanate compound, (b) a polyol compound containing a polycarbonate polyol having an alicyclic structure, and (c) a polyol compound having an acidic group, and (B) a chain elongating agent having a reactivity with the isocyanate group of (A) the polyurethane prepolymer, being dispersed in an aqueous medium, a content of an alicyclic structure is 26.0 to 60.0% by weight in terms of a solid component(s), and a sum of a content of an urethane boding and a content of a urea bonding is 17.7 to 30.0% by weight in terms of a solid component(s).

Abstract: Disclosed is an aqueous polyurethane resin dispersion which comprises a polyurethane resin which is obtained by reacting (A) a polyurethane prepolymer obtained by reacting (a) a polycarbonate polyol having an alicyclic structure in the main chain, (b) an acidic group-containing polyol compound and (d) a polyisocyanate, and (B) a chain-elongating agent, being dispersed in an aqueous medium, a carboxylic acid group content of the above-mentioned (A) polyurethane prepolymer based on a solid component of (A) the polyurethane prepolymer is 2.0 to 13.0% by weight, and a number of a hydroxyl equivalent of a mixture of the above-mentioned (a) polycarbonate polyol having an alicyclic structure in the main chain, the above-mentioned (b) acidic group-containing polyol compound, and, if necessary, (c) a polyol other than (a) and (b) is 70 to 270.

Abstract: A method of producing a polyoxalate resin including polycondensing a dialkyl oxalate represented by formula (2): wherein R represents an alkyl group having 1 to 4 carbon atoms, with a saturated aliphatic diol represented by formula (3): HO-A-OH, wherein A represents a divalent saturated aliphatic hydrocarbon group having 3 to 12 carbon atoms, in which polycondensation reaction product, the molar amount of the dialkyl oxalate [M1] and the molar amount of the saturated aliphatic diol [M2] satisfy relationship (I): 0.5?[M2]/[M1]<1 while controlling the total content of water in the starting reaction mixture to 2,000 ppm or less.

Abstract: A biodegradable polyoxalate resin having a high melt-formability by the formula: X?O-A-O—CO—CO?nY in which A=C3-C12 divalent aliphatic hydrocarbon group, X=H; R—OCOCO— or OHC— group, Y=—OR, —OAOH or —OAOCHO when X=H—, or —OR or —OAOCHO when X=R—OCOCO— or OHC—, R=C1-C4 alkyl, and is usable in a resinous composition with a poly(lactic acid) resin.

Abstract: A crystalline polyesterpolyol having a number average molecular weight of 1,500 to 15,000 and obtainable from a polybasic carboxylic acid component and an aliphatic hydrocarbon diol component comprising 1,10-decanediol and/or 1,12-dodecanediol, and a hot-melt adhesive comprising a reaction product of a polyisocyanate and a polyesterpolyol, which contains a crystalline polyesterpolyol having a number average molecular weight of 1,500 to 15,000 and obtainable from a polybasic carboxylic acid component and an aliphatic hydrocarbon diol component comprising 1,10-decanediol and/or 1,12-dodecanediol are provided.

Abstract: A crystalline polyesterpolyol having a number average molecular weight of 1,500 to 15,000 and obtainable from a polybasic carboxylic acid component and an aliphatic hydrocarbon diol component comprising 1,10-decanediol and/or 1,12-dodecanediol, and a hot-melt adhesive comprising a reaction product of a polyisocyanate and a polyesterpolyol, which contains a crystalline polyesterpolyol having a number average molecular weight of 1,500 to 15,000 and obtainable from a polybasic carboxylic acid component and an aliphatic hydrocarbon diol component comprising 1,10-decanediol and/or 1,12-dodecanediol are provided.

Abstract: This invention provides a hybrid yarn obtained by combining the filaments of a carbon fiber and a specific inorganic fiber composed substantially of elements Si, Ti or Zr, C and O having a ratio of tensile modulus of the inorganic fiber to tensile modulus of the carbon fiber in the range of from 0.6 to 1.4. Further, this invention provides a unidirectional prepreg obtained by unidirectionally arranging the hybrid yarn prepared from a carbon fiber and a specific inorganic fiber and impregnated with a thermosetting resin, and provides a laminated material obtained by laminating the prepregs.

Abstract: A binary image reduction method for reducing a binary original picture at a conversion ratio .alpha..sub.x smaller than 1 in a horizontal direction and at a conversion ratio .alpha..sub.y smaller than 1 in a vertical direction to obtain a converted picture,x satisfying 1/nx>.alpha..sub.x .gtoreq.1/(n.sub.x +1)y satisfying 1/n.sub.y >.alpha..sub.y .gtoreq.1/(n.sub.y +1)where n.sub.x and n.sub.y are natural numbers,The method being composed of the steps of:obtaining a positional relationship between a target of converted pixels of the converted picture and original pixels on the original picture,forming a rectangular area on the original picture having a side of 2(n.sub.x +1) original pixels in the horizontal direction and a side of 2(n.sub.

Abstract: Methacrylic acid can be produced from methacrolein with a high reaction percentage of methacrolein and a high selectivity percentage of methacrylic acid, by bringing a reaction feed containing methacrolein and molecular oxygen into contact with an oxidation catalyst at a temperature of 200 to 450.degree. C, the oxidation catalyst comprising oxides of molybdenum, phosphorus, calcium, at least one element selected from the group consisting of arsenic, bismuth, tin, titanium, tantalum and boron and, optionally, at least one element selected from the group consisting of antimony, niobium and magnesium.