Process for the production of barrier layers for admixtures of polar and non-polar materials on the inner surface of hollow molded parts made of thermoplastics

摘要

For purposes of producing barrier layers on the surfaces of thermoplastics, the surfaces are exposed to a treatment gas containing fluorine. The barrier layers are effective against mixtures of polar or non-polar substances such as, for instance, fuels containing methanol. In order to improve the barrier effect, the cooled-off treatment gas is left to act upon the surface, whose temperature at the beginning of exposure is kept between 60 degrees C. and 250 degrees C. (140 degrees F. and 482 degrees F.).