The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 20, 2007
Filed:
Dec. 24, 2003
Eiichi Iishi, Osaka, JP;
Yoshiyuki Imamiya, Osaka, JP;
Eiichi Iishi, Osaka, JP;
Yoshiyuki Imamiya, Osaka, JP;
Sumitomo Chemical Company, Limited, Osaka-shi, JP;
Abstract
Low-hygroscopic anhydrous mirtazapine crystals having a hygroscopic degree of not more than 0.6% by weight when the crystals are stored in the air having a relative humidity of 75% at 25° C. under atmospheric pressure for 500 hours; a process for preparing anhydrous mirtazapine crystals having a hygroscopic degree of not more than 0.6% by weight when the crystals are stored in the air having a relative humidity of 75% at 25° C. under atmospheric pressure for 500 hours, comprising drying crystals of mirtazapine hydrate; a crystal of a mirtazapine hydrate represented by the formula (I): wherein n is an integer of 1 to 5; and a process for preparing crystals of a mirtazapine hydrate, comprising crystallizing a crude mirtazapine using a water-soluble organic solvent and water. The anhydrous mirtazapine crystals can be suitably used, for instance, as an antidepressant.