Abstract: The present invention relates to a process for purifying Doxercalciferol, a synthetic vitamin D analog, also known as 1?-hydroxy vitamin D2, to the purity greater than 99.5% by crystallization from a mixed solvent of methanol and acetonitrile. Each of the individual impurities can be controlled no more than 0.1% which meets the individual unknown impurities specification requirement of International Conference on Harmonisation (ICH) guideline. The crystallization yield is more than 75% which is suitable for employed as a commercial process.

Abstract: A vertical and a horizontal vacuum sublimation apparatus with high efficiency and processes thereof are provided, especially for the materials with high melting point and low vapor pressure. The vertical sublimation purification apparatus comprises a sublimation channel body, a material rack, a heating evaporation device, a condensation device, an incubating device, and a product scratching device. The horizontal sublimation purification apparatus comprises a sublimation channel body, a material carrier, a heating evaporation device, and two end pipes. The apparatuses of the present invention can be applied to the mass production of high purity chemicals, and are capable of sublimating and purifying OLED illumination layer materials including Alq3, NPB and CuPc, which have high melting temperature and low vapor pressure.

Abstract: A vertical and a horizontal vacuum sublimation apparatus with high efficiency and processes thereof are provided, especially for the materials having high melting point and low vapor pressure. The vertical sublimation purification apparatus comprises a sublimation channel body, a material rack, a heating evaporation device, a condensation device, an incubating device and a product scratching device. The horizontal sublimation purification apparatus comprises a sublimation channel body, a material carrier, a heating evaporation device and two end pipes. The apparatuses of the present invention can be applied on high purity chemicals from mass production, and are capable of sublimating and purifying OLED illumination layer materials including ALq3, NPB and CuPc, which have high melting temperature and low vapor pressure.

Abstract: A method for preparing three types of benzidine compounds in a specific ratio, the method uses two types of diphenylamine compounds and one type of biphenyldihalide compound in a specific ratio as reactants to mix with an organic solvent and an additive to synthesize benzidine compounds in one step. The synthesized three types of benzidine compounds specially perform in a designated mixturing ratio having excellent photoelectric characteristics for a charge transporting layer in an organic photo-conductive drum.

Abstract: A method for preparing three types of benzidine compounds in a specific ratio, the method uses two types of diphenylamine compounds and one type of biphenyldihalide compound in a specific ratio as reactants to mix with an organic solvent and an additive to synthesize benzidine compounds in one step. The synthesized three types of benzidine compounds specially perform in a designated mixturing ratio having excellent photoelectric characteristics for a charge transporting layer in an organic photo-conductive drum.

Abstract: A vertical and a horizontal vacuum sublimation apparatus with high efficiency and processes thereof are provided, especially for the materials having high melting point and low vapor pressure. The vertical sublimation purification apparatus comprises a sublimation channel body, a material rack, a heating evaporation device, a condensation device, an incubating device and a product scratching device. The horizontal sublimation purification apparatus comprises a sublimation channel body, a material carrier, a heating evaporation device and two end pipes. The apparatuses of the present invention can be applied on high purity chemicals from mass production, and are capable of sublimating and purifying OLED illumination layer materials including ALq3, NPB and CuPc, which have high melting temperature and low vapor pressure.