Sumitomo Chemical Company, Limited

Hiroshi Kajikuri

Yasuhiko Higashio

Masaru Kitamura

Keisuke Sugita

Masanobu Matsubara

Hideki Doi

Kenji Kimura

Hiroshi Ichihashi

Hideto Tojima

Tomokazu Nakamura

Eiji Tasaka

An object of the present invention is to provide a low-dusting additive composition which can improve thermal coloration resistance of a thermoplastic resin. This object is achieved by a granular additive composition containing 5 to 70% by weight of fatty calcium and 5 to 50% by weight of a sulfur-based compound represented by the formula (1), wherein an infrared absorption spectrum of the composition has a maximum absorption peak A in which absorbance in 1540 cmto 1543 cmis a maximum value, and a maximum absorption peak B in which absorbance in 1575 cmto 1583 cmis a maximum value, and the absorbances of the peak A and the peak B are a maximum value and a next maximum value in 1540 cmto 1583 cm,(R&#x2014;Y&#x2014;S&#x2014;CHCO)&#x2014;Z&#x2003;&#x2003;(1)where Rrepresents an alkyl group, Y represents a single bond, or a -CHCO&#x2014; group, m represents an integer of 1 to 4, and Z represents an alcohol residue.

Granular additive composition

A process for producing a high purity caprolactam is disclosed in which a crude caprolactam obtained by a catalytic rearrangement of cyclohexanone oxime is subjected (1) to mixing, while stirring, with at least one hydrocarbon selected from the group consisting of aliphatic hydrocarbons and alicyclic hydrocarbons to form a liquid-liquid, two-layer liquid mixture, and then crystallizing caprolactam out of the liquid mixture; (2) to mixing with both at least one hydrocarbon selected from the group consisting of aliphatic hydrocarbons and alicyclic hydrocarbons, and water to form a liquid mixture, separating the liquid mixture into a hydrocarbon layer and a water layer, and then recovering caprolactam from the water layer; or (3) to distillation in the co-presence of at least one aliphatic saturated hydrocarbon of 10 to 18 carbon atoms.

Process for producing a high purity caprolactam

The invention provides a process for producing high quality .epsilon.-caprolactam which comprises allowing crude .epsilon.-caprolactam obtained by gas phase Beckmann rearrangement of cyclohexanone oxime to contact with hydrogen at 100.degree.-200.degree. C. in the presence of a hydrogenation catalyst.

Process for producing .epsilon. -caprolactam

A process for producing a high purity caprolactam is disclosed in which a crude caprolactam obtained by a catalytic rearrangement of cyclohexanone oxime is subjected

.epsilon.-Caprolactam is prepared by bringing cyclohexanone oxime into contact in gas phase with solid catalysts such as a zeolite catalyst in the presence of at least one nitrogen-containing compound selected from the group consisting of ammonia, methylamines and .epsilon.-caprolactam.

.epsilon.-caprolactam

Thermal decomposition of cycloalkanone oximes is inhibited by allowing nitrogen-containing compounds represented by the following formula (1) to coexist with the cycloalkanone oximes:

Method for inhibiting thermal decomposition of cycloalkanone oximes

.epsilon.-Caprolactam is prepared by subjecting cyclohexanone oxime in a gas phase to a catalytic reaction using zeolite catalysts in the presence of water and at least one compound selected from alcohols and ether compounds.

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Ibaraki, Japan

Hiroshi Kajikuri