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)).

Provided is a process for separating an organic isocyanate prepared by reacting an organic amine with a stoichiometric excess of phosgene in the gas phase from the gaseous crude product obtained in the reaction, the process comprising the steps of (i) at least partially condensing the crude product stream containing at least the isocyanate, hydrogen chloride and unconverted phosgene by contacting with at least one liquid stream containing at least one quench liquid in a first separation apparatus to obtain a liquid stream containing at least some of the quench liquid and some of the isocyanate and a gas stream containing at least hydrogen chloride, evaporated quench liquid and phosgene, (ii) discharging the liquid stream obtained in step (i) via a first liquid outlet and of the gas stream obtained in (i) via a first gas conduit and (iii) at least partially condensing and/or absorbing the gas stream discharged in step (ii) through the first gas conduit, wherein that the at least partial condensation and/or absorption is effected in step (iii) by direct introduction of at least one cooling fluid, wherein the cooling fluid is introduced directly into the first gas conduit via at least one addition unit assigned to the first gas conduit.

Provided is a process for separating an organic isocyanate prepared by reacting an organic amine with a stoichiometric excess of phosgene in the gas phase from the gaseous crude product obtained in the reaction, the process comprising the steps of (i) at least partially condensing the crude product stream containing at least the isocyanate, hydrogen chloride and unconverted phosgene by contacting with at least one liquid stream containing at least one quench liquid in a first separation apparatus to obtain a liquid stream containing at least some of the quench liquid and some of the isocyanate and a gas stream containing at least hydrogen chloride, evaporated quench liquid and phosgene, (ii) discharging the liquid stream obtained in step (i) via a first liquid outlet and of the gas stream obtained in (i) via a first gas conduit and (iii) at least partially condensing and/or absorbing the gas stream discharged in step (ii) through the first gas conduit, wherein that the at least partial condensation and/or absorption is effected in step (iii) by direct introduction of at least one cooling fluid, wherein the cooling fluid is introduced directly into the first gas conduit via at least one addition unit assigned to the first gas conduit.

Provided is a process for separating an organic isocyanate prepared by reacting an organic amine with a stoichiometric excess of phosgene in the gas phase from the gaseous crude product obtained in the reaction, the process comprising the steps of (i) at least partially condensing the crude product stream containing at least the isocyanate, hydrogen chloride and unconverted phosgene by contacting with at least one liquid stream containing at least one quench liquid in a first separation apparatus to obtain a liquid stream containing at least some of the quench liquid and some of the isocyanate and a gas stream containing at least hydrogen chloride, evaporated quench liquid and phosgene, (ii) discharging the liquid stream obtained in step (i) via a first liquid outlet and of the gas stream obtained in (i) via a first gas conduit and (iii) at least partially condensing and/or absorbing the gas stream discharged in step (ii) through the first gas conduit, wherein that the at least partial condensation and/or absorption is effected in step (iii) by direct introduction of at least one cooling fluid, wherein the cooling fluid is introduced directly into the first gas conduit via at least one addition unit assigned to the first gas conduit.

A plant for preparing a purified isomeric methylene diphenyl diisocyanate monomer from a mixture of different isomeric monomers is disclosed herein. The plant can comprise a distillation apparatus, which comprises: a) a distillation column including a structured packing, b) a source for a mixture of different isomeric methylene diphenyl diisocyanate monomers, c) an evaporator, d) an overhead vapor condenser, e) optionally, an overhead vacuum system and f) a flow-controlled reflux system. The overhead vapor condenser comprises a shell and tube arrangement and is embodied so as to directly subcool the condensate to less than 47° C. The flow-controlled reflux system comprises a heater, which is embodied so as to reheat a partial stream of the condensate formed in the overhead vapor condenser up to 190° C.

A plant for preparing a purified isomeric methylene diphenyl diisocyanate monomer from a mixture of different isomeric monomers is disclosed herein. The plant can comprise a distillation apparatus, which comprises: a) a distillation column including a structured packing, b) a source for a mixture of different isomeric methylene diphenyl diisocyanate monomers, c) an evaporator, d) an overhead vapor condenser, e) optionally, an overhead vacuum system and f) a flow-controlled reflux system. The overhead vapor condenser comprises a shell and tube arrangement and is embodied so as to directly subcool the condensate to less than 47° C. The flow-controlled reflux system comprises a heater, which is embodied so as to reheat a partial stream of the condensate formed in the overhead vapor condenser up to 190° C.

A plant for preparing a purified isomeric methylene diphenyl diisocyanate monomer from a mixture of different isomeric monomers is disclosed herein. The plant can comprise a distillation apparatus, which comprises: a) a distillation column including a structured packing, b) a source for a mixture of different isomeric methylene diphenyl diisocyanate monomers, c) an evaporator, d) an overhead vapor condenser, e) optionally, an overhead vacuum system and f) a flow-controlled reflux system. The overhead vapor condenser comprises a shell and tube arrangement and is embodied so as to directly subcool the condensate to less than 47° C. The flow-controlled reflux system comprises a heater, which is embodied so as to reheat a partial stream of the condensate formed in the overhead vapor condenser up to 190° C.

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 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.