Which paperboard formats can be tested?
Potential applications include folding cartons, sleeves, cardboard pots, paper labels, corrugated cases, paper bags and coated paperboard. The useful description is not simply “cardboard”: recycled content, surface texture, moisture, print coverage, varnish and colour can all change the response.
A code can be created by darkening the exposed fibre, removing a coloured coating to reveal a pale base, or removing a light area to expose a darker prepared layer. Packaging artwork can deliberately reserve a laser-reactive panel, giving the coder a controlled background across several designs.
When can direct laser coding replace a label?
Direct marking is most attractive when the carton already passes the coder in a controlled orientation and the variable information fits within a reserved field. It can remove the need to buy, store and apply a separate label for date, batch, routing or traceability data.
The comparison should include more than consumables. A label can provide predictable contrast on widely varying case colours and can carry a large amount of information. Laser is strongest where the board is qualified, the mark field is adequate and the permanent code supports the required distribution and verification process.
Planning barcodes and GS1 2D codes
Machine-readable codes place tighter demands on the marking station than plain text. Define the symbology, data length, module size, quiet zones, orientation and expected verification grade before choosing the lens and source power. The code must remain correctly proportioned while the pack is moving.
Downstream vision can check code presence, content or quality and can be linked to a reject or line-stop strategy. The appropriate verification standard and acceptance threshold should be agreed by the packaging owner rather than assumed from a visually sharp sample. See the QR and Data Matrix laser marking guide.
What should a carton trial include?
- Board range: every grade, supplier, colour, finish and recycled-content variant.
- Print and coating: production artwork, varnish and laser-reserved panels.
- Code extremes: longest text, densest 1D or 2D code and smallest required characters.
- Line speed: normal, peak and variable-speed operation using a suitable encoder.
- Pack control: position, flatness, pitch, vibration and distance from the lens.
- Code checks: readability, verification, abrasion and distribution handling.
- Extraction: capture and filtration for the actual ink, varnish and board.
Use representative cartons and the real data format in an Oxford Traceability application trial.