Method and apparatus for producing gas impermeable, chemically inert container structures for food and volatile substances

A method of making a gas-impermeable container wall structure comprising the steps of

• providing a container of an organic polymeric dielectric material;
• creating a relatively high vacuum in the container;
• injecting a plurality of inorganic reactive gases into said container;
• exposing the container and its contents to microwave energy sufficient to ionize said gases and produce a plasma in the container which causes chemical reaction of said gases thereby forming an inorganic vapor compound which becomes deposited on the interior wall of the container;
• pulsing the injecting and exposing steps at a selected frequency to control the temperature and stoichiometry of this deposited vapor compound, and
• continuing the injecting and exposing steps until the compound vapor deposit on said interior wall forms a gas-impermeable, chemically inert barrier layer of a selected thickness on said interior wall.

Apparatus for making a gas-impermeable container wall structure comprising

• means for providing a base layer of an organic polymeric material;
• means for conducting a plurality of reactive gases to the surface of the base layer;
• means for supplying electromagnetic radiation of sufficient strength at said surface to create a plasma which causes chemical reaction of said gases to form an inorganic vapor compound which becomes deposited on said surface;
• means for pulsing the conducting and supplying means to control the temperature and stoichiometry of the deposited vapor compound, and
• means for controlling the conducting and supplying means until the vapor compound deposit on said surface forms a coherent, strongly adherent gas-impermeable, chemically inert barrier layer of the desired thickness on said surface.

Apparatus for making a gas-impermeable container wall structure comprising

• means for providing a container of an organic polymeric dielectric material;
• means for creating a relatively high vacuum in the container;
• means for injecting a plurality of inorganic reactive gases into said container;
• means for exposing the container and its contents to electromagnetic energy sufficient to ionize said gases and produce a plasma in the container which causes chemical reaction of said gases thereby forming an inorganic vapor compound which becomes deposited on the interior wall of the container, and
• means for controlling the injecting and exposing steps until the vapor compound deposited on said interior wall forms a coherent, strongly adherent gas-impermeable, chemically inert barrier layer of a selected thickness on said interior wall, said controlling means causing the injection of said plurality of gases into the container as injection pulses of a selected frequency and the exposure of the container and its content to said energy as energy pulses having said selected frequency.