Article

Advances in pharmaceutical coatings

Authors:
  • Bharati Vidyapeeth's college of Pharmacy, Navi mumbai
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Abstract

Recent trends in pharmaceutical technologies are towards the development of coating methods which overcomes the various disadvantages associated with solvent based coatings. In these newer technologies coating materials are directly coated onto solid dosage forms without using any solvent and then cured by various methods to form a coat, hence these methods sometimes called as solventless coatings. Various solventless coatings are available such as photocurable coating, magnetically assisted impaction coating, compression coating, hot melt coating, powder coating, electrostatic dry coating, supercritical fluid coating, herein only magnetically assisted impaction coating and electrostatic dry coating are discussed. This review summarizes the fundamental principles and coating processes of various dry coating technologies.

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... As a result of the charge difference, they are transported towards the target and deposited. Tribo-charging is another method that uses the frictional charge of powder that is delivered through a pipe made of a certain material, such as PTFE, metal, or other powder particles [213,216,217]. Because tribo-charging leaves less charge on particles than corona charging [218], corona charging is the preferred method for electrostatic powder coating [219]. ...
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