A composition is provided including a compound (A) represented by Formula (1) and a compound (B) represented by Formula (2), wherein the compound (B) is contained in an amount of 0.00002 to 0.2 parts by mass with respect to 100 parts by mass of the compound (A):

(R.sub.1—COO).sub.n—R.sub.2—(NCO).sub.m   (1)

(in Formula (1), R.sub.1 is an ethylenically unsaturated group having 2 to 7 carbon atoms; R.sub.2 is an (m+n)-valent hydrocarbon group having 1 to 7 carbon atoms; and n and m are each an integer of 1 or 2)

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(in Formula (2), R is (—R.sub.2—(OCO—R.sub.1), and R.sub.1 and R.sub.2 are the same as those in Formula (1)).

The invention is related to a composition excellent in stability during storage and excellent stability during utilization, and related to a method of producing the composition. The composition comprises a compound (A) represented by general formula (1) and a compound (B). The compound (B) is an oligomer in which two or more molecules of the compound (A) are bonded to each other by ethylenically unsaturated groups of each compound (A). The composition contains 0.00002 to 0.2 parts by mass of the compound (B) with respect to 100 parts by mass of the compound (A),

(R.sub.1—COO).sub.n—R.sub.2—(NCO).sub.m  (1)

wherein in general formula (1), R.sub.1 is an ethylenically unsaturated group having 2 to 7 carbon atoms; R.sub.2 is a (m+n)-valent hydrocarbon group having 1 to 7 carbon atoms and optionally contain an ether group; and n and in each represent an integer of one or two.

The invention is related to a composition excellent in stability during storage and excellent stability during utilization, and related to a method of producing the composition. The composition comprises a compound (A) represented by general formula (1) and a compound (B). The compound (B) is an oligomer in which two or more molecules of the compound (A) are bonded to each other by ethylenically unsaturated groups of each compound (A). The composition contains 0.00002 to 0.2 parts by mass of the compound (B) with respect to 100 parts by mass of the compound (A),

(R.sub.1—COO).sub.n—R.sub.2—(NCO).sub.m  (1)

wherein in general formula (1), R.sub.1 is an ethylenically unsaturated group having 2 to 7 carbon atoms; R.sub.2 is a (m+n)-valent hydrocarbon group having 1 to 7 carbon atoms and optionally contain an ether group; and n and in each represent an integer of one or two.

The present invention provides a method for producing a carbamate that includes a step (1) and a step (2) described below: (1) a step of producing a compound (A) having a urea linkage, using an organic primary amine having at least one primary amino group per molecule and at least one compound selected from among carbon dioxide and carbonic acid derivatives, at a temperature lower than the thermal dissociation temperature of the urea linkage; and (2) a step of reacting the compound (A) with a carbonate ester to produce a carbamate.

The present invention provides a method for producing a carbamate that includes a step (1) and a step (2) described below: (1) a step of producing a compound (A) having a urea linkage, using an organic primary amine having at least one primary amino group per molecule and at least one compound selected from among carbon dioxide and carbonic acid derivatives, at a temperature lower than the thermal dissociation temperature of the urea linkage; and (2) a step of reacting the compound (A) with a carbonate ester to produce a carbamate.

The invention relates to a composition excellent in stability during storage and stability during utilization, and relates to a method of producing the composition. The composition includes a compound (A) represented by general formula (1) and a compound (B) represented by general formula (2), and includes 0.00002 to 0.2 parts by mass of the compound (B) with respect to 100 parts by mass of the compound (A),

(R.sub.1—COO).sub.n—R.sub.2—(NCO).sub.m  (1)

(R.sub.1—COO).sub.n—R.sub.2—(R.sub.3—R.sub.1).sub.m  (2)

wherein in general formulae (1) and (2), R.sub.1 is an ethylenically unsaturated group having 2 to 7 carbon atoms; R.sub.2 is a (m+n)-valent hydrocarbon group having 1 to 7 carbon atoms and optionally contains an ether group; R.sub.1 and R.sub.2 in the general formula (1) are the same as R.sub.1 and R.sub.2 in the general formula (2); in general formula (2), R.sub.3 is —NHC(═O)—; and n and m each represent an integer of one or two.

In the embodiments, an aqueous hydrochloric acid solution instead of hydrogen chloride gas and solid triphosgene instead of phosgene gas may be used in the process of preparing a diisocyanate from a diamine through a diamine hydrochloride. In addition, the embodiments provide processes for preparing a diisocyanate composition and an optical lens of high quality in which the content of water, the content of cations, or the content of an aromatic compound containing 3 or more of chlorine (Cl) in the organic solvent used in the reaction of a diamine hydrochloride composition and triphosgene is adjusted to a specific range.

In the embodiments, an aqueous hydrochloric acid solution instead of hydrogen chloride gas and solid triphosgene instead of phosgene gas may be used in the process of preparing a diisocyanate from a diamine through a diamine hydrochloride. In addition, the embodiments provide processes for preparing a diisocyanate composition and an optical lens of high quality in which the content of water, the content of cations, or the content of an aromatic compound containing 3 or more of chlorine (Cl) in the organic solvent used in the reaction of a diamine hydrochloride composition and triphosgene is adjusted to a specific range.

Provided are monomers useful for dental materials that include a compound in which a core and a specific terminal group are bonded to each other directly or via a linking group, wherein the core is a C.sub.1-200 polyvalent organic group having a valence of not less than 3 containing an oxygen atom or a nitrogen atom in which an atom bonded to the terminal group or the linking group is the oxygen atom or the nitrogen atom; the terminal group is a specific (meth)acryloyl group-containing group, a (meth)acryloyl group, a C.sub.1-20 hydrocarbon group or a hydrogen atom, and the terminal group needs to meet specific requirements; and the linking group is a specific divalent group, and when the compound contains a plurality of linking groups, the linking groups may be the same as or different from each other. Compositions, dental materials and kits are also provided.

The invention relates to a method for producing an isocyanate, wherein a carbamate or thiolcarbomate is converted, in the presence of a catalyst, with separation of an alcohol or thioalcohol, at a temperature of at least 150 C., to the corresponding isocyanate, wherein a compound of the general formula (X)(Y)(ZH) is used as a catalyst, in particular characterized in that the compound has both a proton donor function and a proton acceptor function. In the catalysts according to the invention, a separable proton is bound to a heteroatom, which is more electronegative than carbon. Said heteroatom is either identical to Z or a component thereof. In the catalysts according to the invention, there is additionally a proton acceptor function which is either identical to X or a component thereof. According to the invention, the proton donator and proton acceptor function are connected to each other by the bridge Y.