Approving colour for gravure packaging

A packaging colour approval needs more information than a signed image on a screen. The press team needs to know which artwork version, substrate and reference the customer approved, together with the conditions used to assess the print.

Give each proof a defined purpose

Use an artwork PDF to approve content, dimensions and placement. Specify separately whether a physical proof is intended as a colour target. For a screen review, agree which decisions can be made from the display and which must wait for a physical sample. This keeps a layout approval from being treated as approval of every printed effect.

Describe the printing condition

Record the film, printing side, ink sequence and any white backing or metallic effect that affects the appearance. Colour-management software can model interactions between the process, inks and substrate. GMG's OpenColor documentation describes these inputs, including overprinting, rather than treating a colour profile as independent of production. See GMG's packaging colour-management overview.

For transparent or metallic materials, ask what the chosen proof can simulate and what still requires a production-representative sample. GMG's substrate-proofing guidance discusses using a white undercoat to simulate ink opacity on metallic substrates. The capability of any particular proofing setup should be confirmed before approval. See GMG's opacity-simulation explanation.

Make the acceptance criteria usable

Identify the reference sample or colour target, the areas to measure and the agreed tolerance. If colour difference is part of acceptance, name the formula and measurement conditions. Keep the viewing conditions, instrument setup and sample backing consistent with the agreed method. A number without those conditions leaves room for different interpretations.

Separate colour from registration, text legibility and surface appearance in the approval record. Each requires its own observation. For effects that the proof does not represent, agree how a production sample will be reviewed.

Keep approval and change control together

Use one approved file version for cylinder preparation and printing. If artwork, film, ink or finish changes, identify which approvals need to be repeated. For a repeat order, send the previous reference and flag any specification changes before work begins.

HUAYN coordinates design, cylinder preparation and printing through the agreed production brief. Send your artwork and colour reference through our contact page, or review the prepress service. Confirm any required proof format or measurement report in the quotation.