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An excessive increase in the size of a halftone dot from film to the printed image. Causes:  -Excessive ink volume; -Excessive plate thickness or plate swelling; -Wrong tape or trapped

A print fault on corrugated substrate characterised by darker lines appearing at the flutes from the uneven surface of the corrugated board. It is caused by the liner as it

Some of the ink’s ingredients go out of suspension, causing loss of ink flow with a tendency to curdle. Causes: – Excessive moisture content of ink due to high humidity

Parallel lines of misprint on the substrate.  Causes: – Gears not meshing together correctly; – Butt-cut dies, sheeter dies and rectangle dies hitting hard against the substrate or anvil sending

A small, solid print area encircled with a white halo. Causes: – Dust on the substrate transferring to the plate; – Excessive ink tack; – Poor coating on paper. Solutions:  – Clean

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;