A barcode that scans on a flat proof may behave differently after a label shrinks around a bottle. For buyers of custom shrink sleeve labels, approval should cover the finished pack—not just the artwork on a screen. This guide focuses on troubleshooting scanning problems and planning the checks before a production order.
1. Separate barcode data from print quality
Start with the approved barcode file and the correct product reference for each SKU. Ask the brand owner to confirm the encoded number, barcode type and destination retailer’s requirements. A readable symbol with the wrong product number is still a packaging error. Keep a simple approval sheet linking each design revision, flavour or size to its approved code.
2. Protect the symbol and its background
GS1 guidance highlights symbol size, clear margins (quiet zones), contrast and placement. Do not squeeze a barcode to fit leftover space, shorten the bars for decoration, or place text inside its required clear margins. The appropriate dimensions depend on the barcode and its scanning application; there is no single size suitable for every sleeve.
Black bars on a white background are the safest starting point for contrast. On transparent film, ask prepress to assess an opaque backing so the bottle or contents do not interfere with the background. Approve this on the actual packaging combination, not a white computer canvas.
3. Review placement before making printing tools
Shrink sleeves change from flat film to a shaped surface. Container contours, film behaviour and the shrink process affect the result. Keep the proposed barcode panel away from the seam and strongly changing contours wherever the layout allows. Ask prepress to confirm its orientation and any necessary compensation for the specific bottle. Rotating or stretching the entire artwork by eye is not an approval method.
For the wider layout process, see our shrink sleeve artwork guide. This article adds the scanning checks rather than replacing the approved dieline.
4. Use the symptom to guide the next check
| Observed problem | What to inspect | Next action before approval |
|---|---|---|
| Flat proof scans; applied sleeve does not | Changed proportions, curvature and the actual position after shrinking | Compare the flat and finished samples with prepress and the sleeve applicator; review placement and shrink conditions. |
| Reading changes when the pack is turned | Curvature, reflections and background contrast | Check representative finished packs under the intended scanning conditions; assess an alternative panel or backing. |
| Only some packs fail | Wrinkles, print defects and variation in application position | Keep failed and successful samples from the same run for comparison instead of approving one good sample. |
| The scanner returns an unexpected item | Encoded data and SKU-to-artwork mapping | Confirm the number with the brand owner and check every affected design revision. |
These are investigation prompts, not a diagnosis from a photograph. More than one issue may be present.
5. Approve the finished pack, not only a phone scan
- Artwork check: confirm the approved code, layout, margins and revision for each SKU.
- Physical trial: use the intended container, sleeve and application conditions. Review the pack after shrinking and cooling.
- Reading and verification: a successful scan is useful, but does not establish a formal print-quality grade. If the buyer or retailer requires verification, agree the applicable method, grade and reporting responsibility before production.
- Production reference: retain the approved artwork and physical sample. Agree how production samples will be checked and how exceptions will be handled.
What should you send for a quotation and artwork review?
- Bottle or jar photographs, dimensions and preferably a physical sample.
- The sleeve artwork, approved barcode file and quantity for each design.
- Any existing film specification and the intended sleeve application method.
- The destination market and any buyer-specific scanning or verification requirements.
- Your required delivery date and delivery location.
We manufacture custom printed shrink sleeve labels. Film, dimensions, artwork suitability and any testing arrangements need to be confirmed for your project; supplying labels does not automatically include applying them to bottles or a certified barcode verification service.
Explore our custom shrink sleeve labels or send your bottle and artwork details for a quotation. Email sales@haosenpack.com or contact us on WhatsApp +86 189 2692 9937.