Abstract: Provided is a high-strength bolt which has a tensile strength of 1,200 MPa or more while exhibiting excellent ductility and delayed facture resistance, and further has an excellent impact toughness which had not been obtained in the conventional high-strength bolt. The high-strength bolt has a tensile strength of 1.2 GPa or more and includes a threaded portion and cylindrical neck portion. The bolt has K of 0.8 or more and satisfies Ho<Hs, where K is defined by the equation: (Ao×Ho)/(As×Hs)=K, in which Ao is an effective cross-sectional area of the cylindrical neck portion with a diameter larger than that of the threaded portion, Ho is a Vickers hardness of a portion at which Ao is measured, As is an effective cross-sectional area of the threaded portion, and Hs is a Vickers hardness of the threaded portion.

Abstract: A protective circuit capable of coping with broad voltage variations of a battery unit to interrupt its charging/discharging current path as damages to the heating unit are prevented from occurrence is disclosed. The protective circuit includes fuses, connected to a charging/discharging current path in series between a battery unit and a charging/discharging control circuit, and a heating unit composed by a series connection of resistors. One of two ends of the resistor which is not connected to the peer resistor is connected to a current path of the fuses. The ends of the resistors not connected to the fuses, are provided with a plurality of terminals selected for connection to a current control element that controls the current flowing through the heating unit, as a range of voltage variations of the battery unit is taken into account.

Abstract: A protective circuit capable of coping with broad voltage variations of a battery unit to interrupt its charging/discharging current path as damages to the heating unit are prevented from occurrence is disclosed. The protective circuit includes fuses, connected to a charging/discharging current path in series between a battery unit and a charging/discharging control circuit, and a heating unit composed by a series connection of resistors. One of two ends of the resistor which is not connected to the peer resistor is connected to a current path of the fuses. The ends of the resistors not connected to the fuses, are provided with a plurality of terminals selected for connection to a current control element that controls the current flowing through the heating unit, as a range of voltage variations of the battery unit is taken into account.

Abstract: A process for producing a flexible polyurethane foam having a low transmissibility at resonance frequency, of which a rebound resilience can be suppressed, without using a foam stabilizer, is provided. In production of a flexible polyurethane foam; an isocyanate containing TDI as the main component is used as an isocyanate; and a polyol containing from 20 to 50 mass % of a polyol (A) having an oxyethylene group content of from 10 to 20 mass % and having a hydroxyl value of from 15 to 56 mgKOH/g, which is obtained by subjecting propylene oxide to ring opening addition polymerization to an initiator by using a double metal cyanide complex catalyst, and further subjecting ethylene oxide to ring opening addition polymerization by using an alkali metal compound catalyst or a phosphazenium catalyst, is used as a polyol.

Abstract: Provided is a high-strength bolt which has a tensile strength of 1,200 MPa or more while exhibiting excellent ductility and delayed facture resistance, and further has an excellent impact toughness which had not been obtained in the conventional high-strength bolt. The high-strength bolt has a tensile strength of 1.2 GPa or more and includes a threaded portion and cylindrical neck portion. The bolt has K of 0.8 or more and satisfies Ho<Hs, where K is defined by the equation: (Ao×Ho)/(As×Hs)=K, in which Ao is an effective cross-sectional area of the cylindrical neck portion with a diameter larger than that of the threaded portion, Ho is a Vickers hardness of a portion at which Ao is measured, As is an effective cross-sectional area of the threaded portion, and Hs is a Vickers hardness of the threaded portion.

Abstract: To provide a hardly colored curable composition having an excellent storage stability while maintaining fast curing properties. A curable composition which comprises a polymer (P) having a polyoxyalkylene chain and a group of the following formula (1) and a compound (S) having a mercapto group and a group of the following formula (2), and which contains from 0.01 to 0.50 part by mass of the compound (S) per 100 parts by mass of the polymer (P): —Si(—X1)3??(1) —Si(—X2)m(—Y2)3-m??(2) wherein symbols have the following meanings: X1 and X2: each independently a C1-6 alkoxy group, Y2: a C1-6 alkyl group, and m: 1, 2 or 3.

Abstract: There are provided a steel for warm working, to be subjected to warm working as various structures, components of cars, and the like, a warm working method thereof, and a steel material and a steel component obtainable from the warm working method. [Solving Means] A steel is to have a particle dispersion type fiber structure formed in the matrix by warm working. The steel is characterized in that the total amount of the dispersed second-phase particles at room temperature is 7×10?3 or more in terms of volume fraction, and the Vickers hardness (HV) is equal to or larger than the hardness H of the following equation (2): H=(5.2?1.2×10?4?)×102??(2) when the steel is subjected to any of annealing, tempering, and aging treatments in the as-unworked state under conditions such that a parameter ? expressed by the following equation (1): ?=T(log t+20)(T; temperature(K), t; time(hr))??(1) is 1.4×104 or more in a prescribed temperature range of 350° C. or more and Ac1 point or less.

Abstract: There is provided an ultrahigh strength steel sheet containing 0.10 to 0.40 mass % of C, 0.01 to 3.5 mass % of Cr, at least one selected from the group consisting of 0.10 to 2.0 mass % of Mo, 0.20 to 1.5 mass % of W, 0.002 to 1.0 mass % of V, 0.002 to 1.0 mass % of Ti and 0.005 to 1.0 mass % of Nb, 0.02 mass % or less of P and 0.01 mass % or less of S as impurities and the balance being Fe and unavoidable impurities based on the total mass of the steel sheet and having a base structure of lower bainite, a prior austenite grain size of 30 ?m or smaller and a tensile strength of 980 MPa or higher. There is also provided an automotive strength part using the ultrahigh strength steel sheet.

Abstract: In a steel plate having tensile strength of 1 GPa or more at the normal temperature, the steel plate is made, stress decrement (SD) after uniform elongation in the stress-strain diagram obtained by using a tabular specimen of which is not less than 1.8×102 MPa, yield ratio (YR) of which is preferably not lower than 0.7, further preferably not lower than 0.8, and matrix structure of which is composed of martensite or bainite, or mixture of martensite and bainite substantially without proeutectoid ferrite, whereby the tough-ductility is improved on a practically utilizable level, and the steel plate becomes possible to be supplied in large quantities by winding up into a coil.

Abstract: A silyl group-containing polymer which can be cured quickly and strongly, and from which a cured product excellent in antifouling properties and weather resistance while maintaining favorable rubber elasticity can be obtained, and having the following formula (1): wherein R1: a group having a hydroxyl group(s) removed from a monohydroxy or polyhydroxy compound having t hydroxyl group(s) in its molecule, R2: a bivalent organic group, R3: a C1-20 monovalent organic group which may have a substituent, X: a hydroxyl group or a hydrolysable group, Y: a bivalent group of the following formula (A) or (B), “a”: an integer of from 1 to 3, r: an integer of from 1 to 1,000, and t: an integer of from 1 to 8, provided that when the silyl group-containing polymer of formula (1) has a plurality of Y's in its molecule, the plurality of Y's may be the same or different, and when t is from 2 to 8, a plurality of monovalent groups bonded to R1 may be the same or different: in the formula (A), R4: a C2-8 alkylene group,

Abstract: To provide a polymer composition whereby the viscosity increase during storage can be suppressed low. A polymer composition comprising from 0.05 to 10 parts by mass of a compound (O) having one phenolic hydroxyl group, per 100 parts by mass of an alkoxysilyl group-containing oxyalkylene polymer (P) having a urethane bond, which is obtained by a urethanization reaction between a polymer (pP) having a polyoxyalkylene chain and a hydroxyl group and a compound (U) having an alkoxysilyl group and an isocyanate group.

Abstract: To provide a curable composition excellent in storage stability. To produce an oxyalkylene polymer (P) having a urethane bond, a polyoxyalkylene chain and an alkoxysilyl group, which comprises subjecting a polymer (pP) having a polyoxyalkylene chain and a hydroxyl group and a compound (U) having an alkoxysilyl group and an isocyanate group, to a urethanization reaction in the presence of a double metal cyanide complex catalyst having an organic ligand, and to provide a curable composition containing the polymer.

Abstract: To provide a hardly colored curable composition having an excellent storage stability while maintaining fast curing properties. A curable composition which comprises a polymer (P) having a polyoxyalkylene chain and a group of the following formula (1) and a compound (S) having a mercapto group and a group of the following formula (2), and which contains from 0.01 to 0.50 part by mass of the compound (S) per 100 parts by mass of the polymer (P): —Si(—X1)3 ??(1) —Si(—X2)m(—Y2)3-m ??(2) wherein symbols have the following meanings: X1 and X2: each independently a C1-6 alkoxy group, Y2: a C1-6 alkyl group, and m: 1, 2 or 3.

Abstract: To provide a silyl group-containing polymer which can be cured quickly and strongly, and from which a cured product excellent in antifouling properties and weather resistance while maintaining favorable rubber elasticity can be obtained, and its production process.

Abstract: A flexible polyurethane foam whereby exceedingly low resilience can be obtained without using a plasticizer and the hardness change due to a temperature change is little; and a process for its production, are provided. The flexible polyurethane foam is characterized by having a core resilience of 30% or lower and a glass transition point within a range of from ?80° C. to ?60° C. The process for producing a flexible polyurethane foam comprises reacting a polyol with a polyisocyanate compound in the presence of a catalyst, a foam stabilizer, and a blowing agent, and is characterized by using as the polyol a polyol(l) having a hydroxyl value of from 5 to 15 mgKOH/g.

Abstract: A process for producing a flexible polyurethane foam having a low transmissibility at resonance frequency, of which a rebound resilience can be suppressed, without using a foam stabilizer, is provided. In production of a flexible polyurethane foam; an isocyanate containing TDI as the main component is used as an isocyanate; and a polyol containing from 20 to 50 mass % of a polyol (A) having an oxyethylene group content of from 10 to 20 mass % and having a hydroxyl value of from 15 to 56 mgKOH/g, which is obtained by subjecting propylene oxide to ring opening addition polymerization to an initiator by using a double metal cyanide complex catalyst, and further subjecting ethylene oxide to ring opening addition polymerization by using an alkali metal compound catalyst or a phosphazenium catalyst, is used as a polyol.

Abstract: A flexible polyurethane foam whereby exceedingly low resilience can be obtained without using a plasticizer and the hardness change due to a temperature change is little; and a process for its production, are provided. The flexible polyurethane foam is characterized by having a core resilience of 30% or lower and a glass transition point within a range of from ?80° C. to ?60° C. The process for producing a flexible polyurethane foam comprises reacting a polyol with a polyisocyanate compound in the presence of a catalyst, a foam stabilizer, and a blowing agent, and is characterized by using as the polyol a polyol(l) having a hydroxyl value of from 5 to 15 mgKOH/g.

Abstract: A flexible polyurethane foam whereby exceedingly low resilience can be obtained without using a plasticizer and the hardness change due to a temperature change is little; and a process for its production, are provided. The flexible polyurethane foam is characterized by having a core resilience of 30% or lower and a glass transition point within a range of from −80° C. to −60° C. The process for producing a flexible polyurethane foam comprises reacting a polyol with a polyisocyanate compound in the presence of a catalyst, a foam stabilizer, and a blowing agent, and is characterized by using as the polyol a polyol (1) having a hydroxyl value of from 5 to 15 mgKOH/g.

Abstract: A method for producing a flexible polyurethane foam in an open state, which comprises reacting a polyol with a polyisocyanate compound in the presence of a catalyst, a blowing agent and a foam stabilizer, wherein as the polyol, a polyol having a hydroxyl value of at most 15 mgKOH/g is used.

Abstract: A flexible polyurethane foam having a core impact resilience of at most 40%, of which the half-width of the resonance transmission peak in the resonance curve is at most 1 Hz.