抄録
The production of crystalline vitamin A has been considered to be difficult in a large scale from natural vitamin A oil. The authors have succeeded in the crystallization of vitamin A acetate in a high yield. The crystalline vitamin A acetate obtained is yellow pillar, melts at 58℃, and shows an ultraviolet absorption maximum at 326.5mμ (ethanol solution) and its extinction coefficient, E^<1%>_<1cm> is 1510〜1520. Ultraviolet as well as infrared absorption spectra and maleic acid anhydride adduct showed that the crystal obtained was a11-trans form. The stability of the crystal was relatively good, being 92.2% after 90 days.
