Product manual

UV Glossary
9-4
Part 1105120-01
E 2013 Nordson Corporation
louver A part of a UV shutter system or shielding section that blocks the UV
light while allowing cooling air to pass through.
magnetron Assembly contained inside a microwave lamphead that converts
high-voltage electrical input into RF energy.
mercury A silver-white metallic element that is liquid at room temperature and is
used to create a vaporized, UV-emitting gas plasma inside a quartz
tube when it is energized through the use of either a voltage arc or
microwave energy. When energized the bulb produces a bright white
UV output. Mercury bulbs have a peak spectral output around 365 nm
and a concentration around 254 nm. In some industries, mercury
bulbs are referred to as H bulbs.
mercury plus (H+) Mercury plus bulbs are only available in microwave systems as it is
difficult to vaporize the additional mercury in an electrode bulb.
metal halide bulb Refer to additive bulb.
micrometer (mm) Unit of length equivalent to one millionth of a meter.
microwave That part of the electromagnetic spectrum associated with the larger
infrared waves and the shorter radio waves.
monomers A molecule of relatively low molecular weight and simple structure
capable of combining with itself or other similar molecules to form
polymers.
nanometer (nm) Unit of length equivalent to one billionth of a meter.
negative cooling When the cooling air for the lamphead is drawn from the area
surrounding the substrate being cured and through the lamphead.
Negative cooling provides exhaust for the UV system if it is ducted to
atmosphere. Negative cooling is most often supplied through a remote
cooling fan.
nitrogen blanketing Refer to nitrogen inerting.
nitrogen inerting When the coating or ink is flooded with a nitrogen blanket to prevent
the coating or ink from oxidizing before cure. Nitrogen inertion reduces
oxygen inhibition.
oligomers A low molecular weight resin or polymer used in a radiation curable
coating.
out-of-focus When a lamphead is located further away from the substrate or closer
to the substrate than the focal distance.
oxidizing When the coating or ink reacts with oxygen and slows the
polymerization process of the cure.