Patent ID: 8975433
Filing Date: 2015-03-10
Classification: C07C,C09J

Abstract:
1. A 2-cyanoacrylate-purifying method for purifying a crude 2-cyanoacrylate having a Hazen color number of 50 or more, the 2-cyanoacrylate being represented by formula (2): wherein R 1 represents an aliphatic hydrocarbon group, an alicyclic hydrocarbon group or an aromatic hydrocarbon group which is saturated or unsaturated and may be substituted with a C1 to C16 substituent, said 2-cyanoacrylate-purifying method comprising the steps of: (a) adding to, the crude 2-cyanoacrylate, at least one kind of a polyhydric aromatic compound selected from the group consisting of resorcin and a compound represented by formula (1): wherein R independently represents a hydrogen atom, a carboxy group, an alkoxycarbonyl group, or an alkoxyalkyloxycarbonyl group; and m is an integer of 3 to 5, n is an integer of 1 to 3, and m +n =6; (b) storing, at a temperature in a range of 0 ° C. to 40 ° C. for 0.5 day or more, the resulting mixture obtained in the step (a); and (c) subjecting the mixture to reduced pressure distillation so as to remove (i) a low-boiling-point fraction by 5 wt % to 40 wt % with respect to the crude 2-cyanoacrylate, and (ii) a high-boiling-point fraction by 10 wt % to 30 wt % with respect to the crude 2-cyanoacrylate, so as to obtain a purified 2-cyanoacrylate having a Hazen color number of 40 or less.