Gas Wedge Injection

Metallizing

GENERAL's Gas Wedge Injection system will give users of vacuum metallizers the following benefits:

Improved Convertibility

At high rewind temperatures, certain films exhibit a loss of surface tension (in extreme cases "blocking" can occur). Under these circumstances the film will not "wet", making it unsuitable for subsequent converting processes like printing or laminating.

GENERAL's Gas Wedge Injection system improves the thermal conductivity between the cooling drum and web, resulting in little or no temperature rise at the rewind. Loss of surface Tension and "blocking" is eliminated.

20um BOPP	Typical Unwind Film Temperature	Typical Rewind Film Temperature
Without Gas Wedge	18 degrees C	26-28 degrees C
With Gas Wedge	18 degrees C	18 degrees C

Removes Tramlines

Films with high co-efficient of friction can be susceptible to "tramlines" caused by heat wrinkles formed when the film expands on the cooling drum.

GENERAL's Gas Wedge Injection system removes tramlines by reducing film expansion by improving the thermal Conductivity between the cooling drum and web. Also by reducing .The co-efficient of friction by injecting a layer of gas between the cooling drum and web to allow the film to slide laterally.