Blow molding plastics bottles, to hold aromatic contents, initially inflates a parison by a low pressure gas followed by ignition of an inflammable precursor gas which coats the inner surface with a barrier layer

摘要

A plastics parison is heated and then expanded by a gas at a low pressure of 2-15 bar followed by the ignition of a flammable gas which increases the inner pressure to give the final container shape. After ignition, the inner surface of the container is coated with e.g. silicon oxide. The precursor gas is mixed before blow molding, and the inner coating is formed during final molding. To blow mold a container (1) from a plastics parison (2), it is heated and then expanded by a gas at a low pressure of 2-15 bar followed by the ignition of a flammable gas which increases the inner pressure to give the final container shape. The flammable gas is a precursor gas based on silicon, magnesium, aluminum, titanium, zinc, zirconium or boron in a gas mixture. After ignition, the inner surface of the container is coated with silicon oxide, silicon oxynitride, magnesium oxide, aluminum oxide, titanium oxide, zinc oxide, zirconium oxide or boron oxide. The precursor gas is mixed before blow molding, and the inner coating is formed during final molding.