Development of Passive and Active Barrier Coatings on the Basis of Inorganic–Organic Polymers

With a new kind of barrier coating material, namely inorganic–organic polymers, it is possible to obtain excellent barrier properties against oxygen, water vapor, and flavor permeation. These hybrid polymers can be synthesized by the sol–gel technique. If extremely low permeation values are needed, the combination of hybrid polymer coatings with thin inorganic oxidic layers (SiO x , AlO x ) is very effective and leads to permeation values for oxygen and water vapor below 10−3 cm3/m2 · d · bar or g/m2 · d. These passive barrier layers can be further improved by the combination with active oxygen barrier layers which have been developed for the food packaging industry. This approach makes these multilayer laminates promising candidates for special applications in the food packaging industry as well as for sophisticated applications in technical areas: the encapsulation of sensitive organic devices like solar cells, organic light emitting diodes, or polymer electronic systems.