How UV Curing Works

In its most basic form, UV curing involves a photo-chemical reaction which converts a liquid or semi-liquid organic compound to a hard plastic-like polymer. The heart of this reaction is a special compound, known as a "photoinitiator", which absorbs light and then uses the absorbed light energy to initiate and propagate the curing reaction.

Unlike conventional drying processes which use heat to evaporate water or solvents from a material, UV curing involves a total conversion of liquid material to a solid state. This lack of solvents makes UV curing an attractive alternative in cases where solvent emissions must be reduced. The hard plastic-like cured polymer has superior physical properties (such as abrasion-resistance, gloss, and chemical resistance). These properties are used effectively in many printing and industrial applications.

The UV curing process is very fast, usually completed in fractions of a second. This means reduced space requirements and a decrease in Work In Process. Racking or secondary drying operations are eliminated with UV curing. In many cases, quality can be improved through the elimination of ink transfer, or surface blemishes caused by contact between a partially dry ink or coating and another surface.

Any UV curing process requires a UV light source and an ink or coating specially formulated for the UV curing process. Both the light source and the UV curable material are normally designed for each specific application.

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