Rowe R C, Forse S F
J Pharm Pharmacol. 1983 Apr;35(4):205-7. doi: 10.1111/j.2042-7158.1983.tb02913.x.
The refractive indices of both the polymer film formers and additives are a fundamental factor in defining the appearance of the subsequent film coatings. The refractive indices of the polymer film formers are all in the region of 1.5 but those of pigments and additives vary between 1.5-3.2. Most pigments and additives are also anisotropic, i.e. they possess different refractive indices depending on their orientation. These observations have implications in the use of pigments and additives for the production of both opaque films with good hiding power and film-coated tablets with highlighted intagliations.
聚合物成膜剂和添加剂的折射率是决定后续薄膜包衣外观的一个基本因素。聚合物成膜剂的折射率都在1.5左右，而颜料和添加剂的折射率在1.5至3.2之间变化。大多数颜料和添加剂也是各向异性的，即它们根据取向具有不同的折射率。这些观察结果对于使用颜料和添加剂来生产具有良好遮盖力的不透明薄膜以及带有突出压纹的薄膜包衣片剂具有重要意义。
