To provide a method of producing an aliphatic polyisocyanate employing a hydrochloride method and capable of shortening the operation time in its production process to improve its productivity.
The method of producing an aliphatic polyisocyanate comprising a first reaction process of allowing an aliphatic polyamine to react with hydrogen chloride in a first reaction tank 10 in the presence of an inert organic solvent, subsequently allowing the reaction product to react with phosgene, and keeping the resulting reaction liquid at a specified temperature, a second reaction process of keeping the reaction liquid produced in the first reaction process in a second reaction tank 11 at a specified temperature, and a separation process of separating aliphatic polyisocyanate from the reaction liquid produced in the second reaction process, with the first reaction process employing a plurality of first reaction tanks 10, is characterized by starting, while a first reaction process is in progress in one of the first reaction tanks 10, another first reaction process in another of the first reaction tanks 10, and feeding the reaction liquid alternately from the plurality of first reaction tanks 10 to the second reaction tank 11.
KAIGAWA TAKESHI
MIYAMOTO SHINICHI
Makoto Suhara
Toru Kimura
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