Methods for coating technology for plastic containers

A method for production of a coating for producing a chemically resistant migration barrier on a plastic substrate, by means of plasma-enhanced chemical vapor deposition (PECVD) wherein a process gas mixture is fed into a reaction space;

• and is excited by means of an energy source with an excitation energy to form a plasma, the process gas mixture having an adjustable composition of one or more precursors and/or one or more reactive gases, characterized in that a gradient coat with an adhesion zone, a barrier zone and a passivation zone or a gradient coat with a barrier zone and a passivation zone is deposited on the plastic substrate in which a gradient coat chemical configuration changes along a layer build-up direction between organic and oxidic, wherein the deposition of the gradient coat is controlled by varying a reactive gas content in the process gas mixture, and wherein the excitation energy is controlled on a mass-related basis as a function of a precursor gas mass flow and a reactive gas mass flow, a mass-related excitation energy being reduced along the layer build-up direction for a deposition of an organically characterized passivation zone on an oxidically characterized barrier zone.