Buyer guide · Print files
How is white ink controlled on packaging?
White ink must be evaluated for opacity, layer order, registration, pinholes and colour effect on the actual transparent, metallic or coloured substrate.
Submit project requirements
Checklist
Files and references to prepare
- White ink opacity
- Overprint and trapping
- Material specification
- Proof purpose
- Target quantity and SKU allocation
- Approval sample and decision owner
- Required date and Mainland China delivery point
- Change and repeat-order record
Prepress control
Four checks before releasing artwork
White ink opacity
Define whether white is a base layer, graphic colour or blocker and approve density on the actual transparent or coloured substrate.
Overprint and trapping
Review knockout, overprint, rich black, small reversed text and trapping rules with the selected print process and substrate.
Material specification
Name the grade, composition, colour, surface and approved equivalent; a generic material name is rarely enough for repeat production.
Proof purpose
State whether the proof approves structure, layout, colour direction, material or finished process because one proof rarely confirms everything.
Execution method
Four actions from RFQ to production
Use the production dieline
Place artwork only after the final structure and dimensions are confirmed.
Create a preflight report
Flag missing fonts, low-resolution images, colour spaces, overprint and finishing layers.
Approve the right proof
Match proof type to the question being approved: content, structure, colour or finish.
Archive the released package
Keep the final PDF, source assets, version record and approval together.
FAQ
Questions buyers often ask
How is white ink controlled on packaging?
White ink must be evaluated for opacity, layer order, registration, pinholes and colour effect on the actual transparent, metallic or coloured substrate.
What should be written in the specification?
At minimum, define White ink opacity, Overprint and trapping, Material specification, Proof purpose, then link quantity, sample, timing, inspection and the approved revision.
Is a physical sample needed?
A decision involving structure, material, colour, finish, assembly or use performance normally needs a physical sample matched to that question; a screen proof cannot approve everything.
Can the previous standard be reused for a repeat order?
Reuse a controlled standard only when files, material, structure, supply chain and use conditions remain unchanged. Record every change and decide whether resampling or reapproval is required.
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