Inkjet code adhesion and rub testing
Approve the exact ink, pack and process combination using representative samples, controlled settings and handling checks that reflect production.
Use packaging in its real production condition
Plastic family names, glass, metal, film and board do not predict adhesion on their own. Coatings, surface treatment, release agents, recycled content, oil, dust, condensation and temperature can change how ink wets and dries. Samples should come from current production suppliers and include the least favourable approved condition.
Identify the sample
Record material, supplier, grade, colour, coating, batch and whether the surface has been filled, chilled, washed or handled.
Control the print
Record printer, head, ink or cartridge, message, resolution, speed, throw distance, orientation and environmental conditions.
Define acceptance
Agree the drying time, visual quality, rub method, chemical or water exposure and any scanner or verifier requirement.
Move from initial print to finished-pack durability
Condition samples
Bring packs to the normal printing temperature and include cold, damp or dusty samples where those conditions occur.
Print the full message
Use the smallest characters and machine-readable codes intended for production, not a simple demonstration word.
Measure dry time
Check at agreed intervals before the code meets guides, belts, labels, sleeves, cartons or operator handling.
Apply repeatable rub
Define material, load, strokes and direction so results can be compared rather than judged by an unrecorded finger wipe.
Apply process exposure
Where relevant, test water, condensation, oil, cleaning chemical, heat, chilling, abrasion or transport handling.
Inspect and retain
Record images, pass/fail result, settings and retained samples linked to the approved consumable and pack.
Change one variable at a time
| Observed problem | Variables to investigate |
|---|---|
| Ink beads or pulls away | Surface energy, contamination, coating, wrong ink chemistry or excessive print distance. |
| Code wipes before packing | Dry time, line speed, contact point, ink deposit, temperature and airflow. |
| Code rubs off later | Ink/substrate bond, abrasion, cleaning exposure, pack flexing and downstream friction. |
| Code varies across suppliers | Material construction, coating, treatment, colour and storage differences. |
| Readable text but poor barcode | Module size, edge definition, contrast, distortion, quiet zone and verification grade. |
| Good bench sample, poor line result | Product movement, throw distance, condensation, dust, speed and contact after print. |
Approval is specific to the tested combination
Repeat or review the test when the packaging supplier, material, coating, ink, cartridge, printer settings, code size, production speed or environmental condition changes. Keep the approved record with the production specification.
What to send for an adhesion assessment
- Enough unused production packs to cover all relevant materials, colours and conditions.
- The complete date, batch, barcode or 2D-code artwork at the intended size.
- Line speed, print position, available gap and time before the code is touched.
- Normal product temperature, condensation, dust, oil, cleaning and downstream handling.
- The written acceptance method and any retailer, customer or quality-system requirement.
Send production-grade samples and the full handling conditions for a controlled trial.
Arrange a sample coding reviewWhy can a readable inkjet code still fail a production trial?
A code may look clear immediately after printing yet perform differently during handling or storage. Specify the pack surface, production conditions and required durability. Trial the actual code on representative material and check readability and adhesion at the points that matter in your process, alongside the data-change procedure.
- Actual surface and conditions
- Readability after handling
- Code changes and verification
Related guidance: Inkjet code smudging · Thermal inkjet printers