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Ink film cracks or breaks on substrate when flexed. Causes:  – Excessive heat or UV exposure level in drying/curing system causing a moisture and plasticizer release from the substrate or

Ink dried on plates and rollers and not transferring to substrate, normally found on leading edge of substrate. Causes:  – Low pH due to loss of amine; – Uncontrolled viscosity;

One colour bleeds into another. Colours do not overprint (trap) correctly. Ink picks off or transfers to press rollers. Print blocks in reels. Causes:  – First colour down is drying

The presence of a faint image of a design in areas, which are not intended to receive that portion of the image. Usually a repeat pattern in the press machine

Creases form in substrate. Causes:  -Baggy substrate; – Web guide not operating or properly set; – Press out of alignment; – Foreign matter on press rollers; – Excessive web temperatures;

Excessive foam present in the printing unit, tray or ink pump unit. Causes:  – Ink too weak or too low in viscosity; – Plate surface uneven; – A coating left

An undesired adhesion between touching layers of material caused by moderate pressure and/or temperature change. The extent to which damage to at least one surface is visible upon their separation.

Poor or no ink transfer onto the substrate, evident as a partial image or a missing portion.  Causes:  – Low areas on the plate; – Poor plates or make ready; –

An undesirable peripheral outline around the edges of the printed image. There are two halo faults: Causes: – Too much impression pressure between the plate and substrate; – Too much

Print can be removed by scratching the surface. Print fails adhesion tape, rub or wrinkle tests. Causes: – Wrong ink used for substrate; – Ink over-thinned; – Wrong or weak