Abstract: Provided is a fluoroelastomer crosslinkable composition containing: a polyol-crosslinkable fluoroelastomer (a); and a cross-linking agent (b), wherein the cross-linking agent (b) is at least one selected from the group consisting of a compound represented by the general formula (b1) set forth in the description, a compound represented by the general formula (b2) set forth in the description, and a salt of each of the compounds with an alkali metal, an alkaline earth metal, or an onium compound.

Abstract: A method for producing an aqueous dispersion of a fluorine-containing elastomer, which includes polymerizing a fluorine-containing monomer in the presence of an aqueous medium and a fluorine-containing compound (A), wherein the fluorine-containing elastomer contains a methylene group in a main chain, the fluorine-containing compound (A) is a compound represented by general formula (A): CXiXk?CXjRa—(CZ1Z2)k—Y3??(A) wherein Xi, Xj, and Xk are the same or different and are F, Cl, H, or CF3; Y3 is a hydrophilic group; Ra is a linking group; Z1 and Z2 are the same or different and are H, F, or CF3; and k is 0 or 1; provided that at least one of Xi, Xk, Xj, Ra, Z1, and Z2 includes F; and the number of carbon atoms in a portion excluding the hydrophilic group is 6 or less, and the fluorine-containing compound (A) is fed after polymerization is initiated.

Abstract: Provided is a fluoroelastomer crosslinkable composition, containing a polyol-crosslinkable fluoroelastomer (a) and a cross-linking agent (b), wherein the cross-linking agent (b) is at least one selected from the group consisting of a compound represented by the general formula (b) set forth in the description and a salt of the compound with an alkali metal, an alkaline earth metal, or an onium compound.

Abstract: The present invention makes it possible to provide a compound represented by formula (1) and a composition for an optical material containing this compound. (Where m+n=4, m represents an integer of from 0 to 3, and n represents an integer of from 1 to 4.) In addition, the present invention makes it possible to provide a method for producing an optical material, the method including a step for adding 0.0001-10 parts by mass of a polymerization catalyst per 100 parts by mass of the composition for an optical material, polymerizing, and curing.

Abstract: The present invention enables provision of a production method for 1,2,3,5,6-pentathiepane, the method comprising, in the following order, step A for reacting a trithiocarbonate, sulfur, and a methane dihalide together using a phase-transfer catalyst in a multilayer system having a water layer and an organic layer, step B for separating the water layer from the organic layer, and step C for stopping the reaction using an acid.

Abstract: A composition that includes Compound (a) and Compound (b). Compound (a) is represented by formula (1): where: Ar represents an aromatic ring; m represents an integer of 2 to 8; n represents an integer of 0 to 6, provided that m+n is the number of carbon atoms constituting the aromatic ring, or less; and R1 each independently represents an alkylthio group, a halogen group, a hydroxy group, a dialkylthiocarbamoyl group, or a dialkylcarbamoylthio group. Compound (b) is represented by formula (2): where p represents an integer of 0 to 4, and q represents an integer of 0 to 2.

Abstract: Provided is a fluoroelastomer crosslinkable composition containing: a polyol-crosslinkable fluoroelastomer (a); and a cross-linking agent (b), wherein the cross-linking agent (b) is at least one selected from the group consisting of a compound represented by the following general formula (b) and a salt of the compound with an alkali metal, an alkaline earth metal, or an onium compound. (wherein all symbols are as defined in the specification).

Abstract: A fluoroelastomer crosslinkable composition containing: a polyol-crosslinkable fluoroelastomer (a); and a cross-linking agent (b), wherein the cross-linking agent (b) is at least one selected from a compound that has a structure represented by the following general formula (b) in its molecule and that does not contain a fluorine atom, and a salt of the compound with an alkali metal, an alkaline earth metal, or an onium compound: wherein all symbols are as defined in the specification. Also disclosed are a formed article and sealing material obtained from the fluoroelastomer crosslinkable composition.

Abstract: A fluoroelastomer crosslinkable composition containing a polyol-crosslinkable fluoroelastomer (a) and a cross-linking agent (b), wherein the cross-linking agent (b) is at least one selected from a compound represented by the general formula (b1) set forth in the description, a compound represented by the general formula (b2) set forth in the description, and a salt of any of these compounds with an alkali metal, an alkaline earth metal, or an onium compound. Also disclosed are a formed article and sealing material obtained from the fluoroelastomer crosslinkable composition.

Abstract: A fluoroelastomer crosslinkable composition including a polyol-crosslinkable fluoroelastomer (a) and a cross-linking agent (b), wherein the cross-linking agent (b) is at least one selected from a compound represented by the following general formula (b) and a salt of the compound with an alkali metal, an alkaline earth metal, or an onium compound: wherein respective symbols are the same as those defined in the specification. Also disclosed are a formed article and sealing material obtained from the fluoroelastomer crosslinkable composition.

Abstract: Provided is a composition for optical materials that gives optical materials which can have at least one improved property selected from among satisfactory mold releasability after polymerization and curing, unsusceptibility to separation from the mold during polymerization and curing, transparency, and low-level striae. The present invention further provides a compound represented by formula (1). The composition for optical materials comprises the compound represented by formula (1) and a compound represented by formula (2). (In formula (1), X1 and X2 represent O or S, provided that both X1 and X2 are O or that X1 is O and X2 is S.

Abstract: A composition containing: a compound (a) represented by Formula (1): wherein Ar represents an aromatic ring, m represents an integer of 2 to 8, n represents an integer of 0 to 6, provided that m+n is equal to or less than a number of carbon atoms that constitute the aromatic ring, and R1 each independently represents an alkylthio group, an epoxyalkylthio group, a thiol group, a halogen group, a hydroxy group, a dialkylthiocarbamoyl group, or a dialkylcarbamoylthio group; and 1,2,3,5,6-pentathiepane (b).

Abstract: A composition containing: a compound (a) represented by Formula (1): wherein Ar represents an aromatic ring, m represents an integer of 2 to 8, n represents an integer of 0 to 6, provided that m+n is equal to or less than a number of carbon atoms that constitute the aromatic ring, and R1 each independently represents an alkylthio group, an epoxyalkylthio group, a thiol group, a halogen group, a hydroxy group, a dialkylthiocarbamoyl group, or a dialkylcarbamoylthio group; and a polythiol (b).

Abstract: Provided is a method for producing an aqueous dispersion of a fluorine-containing elastomer, comprising polymerizing a fluorine-containing monomer in the presence of a polymer (1) containing a polymerization unit (1) based on a monomer (1) represented by general formula (1) and an aqueous medium, CF2?CF—R—CZ1Z2—COOM??(1) wherein R is a linking group, Z1 and Z2 are each independently F or CF3, and M is H, a metal atom, NR74, imidazolium optionally having a substituent, pyridinium optionally having a substituent, or phosphonium optionally having a substituent, wherein R7 is H or an organic group.

Abstract: The present disclosure provides a fluoroelastomer crosslinkable composition, the composition containing (a) a polyol-crosslinkable fluoroelastomer and (b) a cross-linking agent, wherein the cross-linking agent (b) is at least one selected from the group consisting of a compound represented by the general formula (b1) set forth in the description, a compound represented by the general formula (b2) set forth in the description, a compound represented by the general formula (b3) set forth in the description, and a salt of any of these compounds with an alkali metal, an alkaline earth metal, or an onium compound.

Abstract: A method for producing an aqueous dispersion of a fluorine-containing elastomer, including polymerizing a fluorine-containing monomer in the presence of a compound (1) having an aromatic ring, a hydrophilic group, and an unsaturated double bond, and an aqueous medium, to produce an aqueous dispersion of a fluorine-containing elastomer containing -CH2- in a main chain.

Abstract: Provided is a fluoroelastomer crosslinkable composition, containing a polyol-crosslinkable fluoroelastomer (a) and a cross-linking agent (b), wherein the cross-linking agent (b) is at least one selected from the group consisting of a compound represented by the general formula (b) set forth in the description and a salt of the compound with an alkali metal, an alkaline earth metal, or an onium compound.

Abstract: Provided is a method for producing an aqueous dispersion of a fluorine-containing elastomer, comprising polymerizing a fluorine-containing monomer in the presence of a compound (1) having a triple bond and a hydrophilic group and an aqueous medium to produce an aqueous dispersion of a fluorine-containing elastomer.

Abstract: Provided is a method for producing an aqueous dispersion of a fluorine-containing elastomer, comprising polymerizing a fluorine-containing monomer in the presence of a fluorine-containing compound (1) represented by general formula (1) and an aqueous medium to produce an aqueous dispersion of a fluorine-containing elastomer: CX1X2?CX3—Z??General formula (1): wherein X1 to X3 are each independently H, F, or a fluorine-containing alkyl group; when X1 and X2 are both H, X3 is F or a fluorine-containing alkyl group; Z is a group represented by —COOM, —SO3M, —OSO3M, —PO(OM)2, —OPO(OM)2, —BO(OM)2, or —OBO(OM)2; M is H, a metal atom, NR14, optionally substituted imidazolium, optionally substituted pyridinium, or optionally substituted phosphonium; and R1 is independently H or an organic group, and any two R1 are optionally bonded to each other to form a ring.

Abstract: A method for producing an aqueous dispersion of a fluorine-containing elastomer, which includes polymerizing a fluorine-containing monomer in the presence of a fluorine-free compound (1) represented by general formula (1): CR1X1?CX2—R2—COOM and an aqueous medium, to produce an aqueous dispersion of the fluorine-containing elastomer containing —CH2— in a main chain. Also disclosed is an aqueous dispersion of the fluorine-containing elastomer and a composition containing the fluorine-containing elastomer.