Pharmaceutical Coating Technology (Part 13)
Film coat quality
Michael E.Aulton and Andrew M.Twitchell SUMMARY This chapter discusses the desirable properties of polymer film coats with respect to their end usage. The mechanical properties of films were discussed fully in Chapter 12 and so this chapter concentrates on other aspects of film quality such as gloss and roughness, uniformity of film thickness and defects such as cracking, edge splitting, picking, bridging and foam filling of intagliations, etc. The methods of assessing film coat quality by visual observation, light section microscopy, surface profilimetry and scanning electron microscopy are discussed. Other techniques such as dissolution, adhesion measurements...