Studies on the light transmittance of coloured plastic bottles for liquid pharmaceutical preparations. Part 43: Contributions to problems concerning the use of plastic containers for liquid pharmaceutical preparations
Beyrich, T.; Tibussek, P.
Die Pharmazie 36(5): 337-341
1981
ISSN/ISBN: 0031-7144 PMID: 7267683 Document Number: 182288
To assess the light transmittance of coloured plastic bottles, studies were made using the photographic paper method and a spectrophotometric technique. According to its sensitivity between 400 and 500 nm, the photographic paper gives information as to this wavelength range, directional radiation and scattered light being covered. In contrast to this, the spectrophotometric method yields discriminating information on the wavelength range between 200 and 800 nm. Apart from a minimum transmittance up to 500 nm, the coloured plastic bottles should have a high transmittance greater than 700 to ensure high transparency. Of the dyes tested, Pigment Orange and Chromeophthal Brown give the plastic bottles light-protecting properties 4 years' storage, both of these dyes show changes in the light-protecting properties by which the light transmittance of plastic bottles coloured with them is increased. When these dyes are used in adequate concentrations, this increase in light transmittance will remain within allowable limits, provided direct solar radiation be avoided.