Cold foil defects usually show up as visible symptoms first: pinholes, ghosting, missing transfer, wrinkles, foil dust, registration drift or poor adhesion. This guide helps press teams diagnose the likely cause, check the right press variables first and decide when to request foil, adhesive or sample support.
How do you diagnose cold foil defects by symptom?
Diagnose cold foil defects by starting with the visible symptom, then checking the most likely variables in order: substrate surface, UV adhesive laydown, anilox condition, foil roll quality, web tension, nip pressure, UV cure and press speed. Record the approved setup and compare defect samples against clean transfer, adhesion and rub-resistance checks.
The images in this guide are photo-style visual examples created to illustrate each symptom. They are not customer production photos, and they are intended as a reference for shape, pattern and distribution of the defect — not as a substitute for inspecting your own samples under magnification.
Cold Foil Defect Diagnosis Matrix
| Visible symptom | What it looks like | Likely causes | First checks | Fix sequence | When to ask CFS |
|---|---|---|---|---|---|
| Pinholes | Small unfoiled dots inside metallic areas | Adhesive starvation, dust, worn anilox, poor wetting | Anilox cell condition, adhesive laydown, substrate cleanliness | Clean web and anilox, raise laydown, re-run short test | Pinholes persist on a clean substrate with correct laydown |
| Ghosting or shadow image | Faint repeated image or metallic haze beside the artwork | Adhesive carryover, tension instability, plate or anilox issue | Plate condition, tension trace, web path rollers | Stabilise tension, clean plate and rollers, correct nip | Ghosting repeats across substrates and presses |
| Incomplete transfer | Broken metallic coverage inside solids | Low laydown, weak cure, poor surface, speed too high | Adhesive film weight, UV output, press speed | Reduce speed, verify cure, increase laydown, retest | Coverage still breaks after cure and laydown are confirmed |
| Poor adhesion or flaking | Metal lifts during tape pull, rub or die-cutting | Adhesive mismatch, under-cure, low surface energy, incompatible varnish | Tape pull result, dyne level, lamp hours, varnish type | Confirm cure, correct surface treatment, review varnish | Adhesion fails with correct cure and treatment |
| Wrinkles or creases | Diagonal lines and crushed metallic streaks | Unstable tension, damaged roll edge, misalignment, high nip | Roll edge condition, tension setpoints, roller parallelism | Re-web the roll, reset tension, reduce nip | Wrinkles appear on new rolls with stable tension |
| Foil dust or dirty edges | Loose metallic particles, rough edge definition | Slitting quality, excess pressure, release mismatch, worn tooling | Edge quality of the roll, nip pressure, static control | Lower pressure, add cleaning and static control, review release | Dust returns with clean tooling and correct pressure |
| Registration drift | Metallic image shifts away from printed artwork | Tension swings, acceleration, web guide fault, substrate stretch | Tension at speed, guide tracking, temperature stability | Stabilise tension ramp, correct guide, hold speed steady | Drift occurs only with a specific foil or substrate |
| Muddy edges or filled fine text | Fine detail closes in, edges lose definition | Adhesive spread, high laydown, plate durometer, excess nip | Laydown weight, plate specification, pressure setting | Reduce laydown, review plate and pressure, retest fine detail | Fine detail cannot be held at a workable laydown |
| Uneven metallic density | Patchy brightness across the same solid | Anilox wear bands, roller deflection, coating variation | Anilox mapping, pressure profile across the web | Rotate or replace anilox, correct pressure profile | Density varies with a specific roll or batch |
| Foil lifting after overprint | Metal lifts after varnish, lamination or die-cutting | Varnish chemistry, cure window, converting stress | Overprint compatibility, cure record, converting sequence | Adjust varnish or cure, revise converting order | Overprint compatibility needs a foil recommendation |
| Random missing spots | Isolated blank areas with no pattern | Contamination, static, dust, air entrapment | Web cleanliness, static bars, roll storage | Clean, control static, condition material, retest | Spots continue with a clean and conditioned web |
| Poor transfer on BOPP or film | Weak or patchy metal on film labels | Low surface energy, treatment loss, adhesive mismatch | Dyne test, treatment date, adhesive selection | Re-treat or re-qualify film, change adhesive, retest | Film transfer stays weak after treatment is confirmed |
Use the matrix as a triage tool. Confirm exact settings with your adhesive, foil and press supplier — target values differ by press, lamp configuration, substrate and foil release grade. For a wider fault list, see our cold foil troubleshooting guide.
Cold Foil Defect Photo Examples
—Pinholes
Visible signs: small white or unfoiled dots inside metallic areas, often clustered rather than evenly spread.
Likely causes: adhesive starvation, contaminated substrate, anilox wear, airborne dust, poor wetting on a sealed or heavily calendered surface.
First checks: inspect the anilox for plugged or worn cells, measure adhesive laydown, wipe a sample area and re-run, and check the web cleaner and static control.
Fix order: clean the web and anilox, correct laydown, confirm surface cleanliness, then re-run a short controlled test before changing material.
Related reading: pinholing and ghosting diagnosis.
—Ghosting
Visible signs: a faint repeated image, shadow transfer beside the intended shape, or uneven metallic haze across the panel.
Likely causes: adhesive carryover on rollers, tension instability, plate or anilox condition, and web path memory from a previous job.
First checks: look at the tension trace during acceleration, inspect the plate and all contact rollers, and review whether the shadow repeats at a fixed cylinder interval.
Fix order: clean contact surfaces, stabilise tension, correct nip settings, then verify the pattern has disappeared at production speed.
Related reading: pinholing and ghosting diagnosis.
—Incomplete transfer
Visible signs: missing metal inside solid areas, broken coverage, or transfer that fades toward one edge of the panel.
Likely causes: low adhesive laydown, weak UV cure, poor substrate surface, or press speed above the cure and transfer window.
First checks: verify lamp output and lamp hours, measure film weight, then reduce speed in steps and observe whether coverage recovers.
Fix order: correct cure first, then laydown, then speed, and only afterwards evaluate a different foil release grade. Adhesive selection is covered in our UV cold foil adhesive setup notes.
—Poor adhesion or flaking
Visible signs: metal lifts during a tape pull, rub test, die-cutting or overprint, sometimes only at trim edges.
Likely causes: adhesive mismatch, under-cure, low surface energy, or an incompatible varnish or lamination adhesive applied over the metallic layer.
First checks: run a controlled tape pull on fresh and aged samples, check dyne level, record lamp hours, and confirm the varnish is approved for metallised surfaces.
Fix order: confirm cure, correct surface treatment, review overprint chemistry, then re-test with the documented method in our cold foil adhesion test method.
—Wrinkles or creases
Visible signs: diagonal lines, crushed metal, and folded metallic streaks that repeat along the web.
Likely causes: unstable web tension, roll edge damage, roller misalignment, or excessive nip pressure at the transfer station.
First checks: inspect roll edges before mounting, check roller parallelism, and record tension at start-up, at speed and during deceleration.
Fix order: re-web the roll, reset tension zones, reduce nip, then re-run. Setup discipline is covered in the cold foil press setup checklist.
—Foil dust or dirty edges
Visible signs: loose metallic particles around the image, dirty fine type, and rough edge definition under magnification.
Likely causes: slitting quality, excessive transfer pressure, release mismatch, worn tooling, or static attracting debris back onto the web.
First checks: examine the slit edge of the roll, measure nip pressure, verify static bars are working, and check tooling for wear.
Fix order: lower pressure, improve cleaning and static control, review the release grade, then reassess the fine detail. See the cold foil troubleshooting guide for related faults.
—Registration drift
Visible signs: the metallic image sits away from the adhesive image or printed artwork, often worsening as the run continues.
Likely causes: tension instability, press acceleration, web guide faults, temperature change, or substrate stretch on thin films.
First checks: compare registration at start-up and at full speed, review the guide tracking, and log ambient temperature and humidity.
Fix order: stabilise the tension ramp, correct the guide, hold a steady speed, then re-check against the approved sample. The cold foil press setup checklist lists the setpoints worth recording.
—Poor transfer on BOPP or film
Visible signs: the metallic layer does not wet evenly on film labels, with weak bonding or random missing areas.
Likely causes: low surface energy, corona treatment that has decayed in storage, adhesive mismatch, or slip additives migrating to the surface.
First checks: dyne test the film at the point of use, confirm the treatment date, and compare a freshly treated sample against stored stock.
Fix order: re-treat or re-qualify the film, adjust the adhesive, then re-test. Film-specific guidance is in cold foil on BOPP labels.
What should you check before changing cold foil?
Replacing the foil is often the first reaction and rarely the first correct step. Most repeat defects trace back to the substrate surface, adhesive laydown, cure or tension — variables that stay wrong even after a new roll is mounted. Work through the sequence below before you order a different grade, and document what changed at each step so the result is reproducible.
- 1Compare with the approved sample under the same light and magnification
- 2Check substrate surface, treatment level and cleanliness
- 3Confirm adhesive batch, viscosity and storage condition
- 4Inspect the anilox and plate for wear, plugging or damage
- 5Verify foil roll direction, edge condition and core mounting
- 6Stabilise web tension and nip pressure across the full speed range
- 7Check UV lamp condition, reflector cleanliness and measured cure
- 8Run a controlled short test with one variable changed at a time
- 9Document the fixed setup so the next run starts from a known state
What information should you send for defect diagnosis?
A good diagnosis depends on the detail supplied with the samples. Send the following with your enquiry so the review can focus on cause rather than guesswork:
- Clear defect photos, including one overview and one macro shot
- Substrate type, grade and supplier
- Label or carton application and end use
- Press model and web width
- Print process and station sequence
- Adhesive type and batch
- Anilox specification
- Foil colour or effect and roll reference
- Running speed when the defect appears
- UV lamp type, output and hours
- Tension and nip settings where available
- Artwork coverage and the smallest detail being held
- Whether the defect is continuous or random
- Whether it appears before or after overprint
- Documents required, such as TDS, SDS or COA — see technical datasheets and documentation
With that package, most symptoms can be narrowed to one or two probable causes without a site visit. Request a defect diagnosis and include the list above.
When should you request a sample kit?
A sample kit is worth requesting when a defect repeats across different substrates, when a new substrate or adhesive is being qualified, or when a brand owner requires approval before production. Testing several grades side by side on your own press separates a material issue from a process issue far faster than adjusting one variable at a time in production.
It also helps when you are moving an existing job to a new press, changing supplier, or introducing film labels alongside paper stock. Order a cold foil sample kit and run the swatches against the same artwork and cure settings you use in production.
Frequently asked questions
What are the most common cold foil defects? +
The most frequent symptoms are pinholes, ghosting, incomplete transfer, poor adhesion, wrinkles, foil dust, registration drift and weak transfer on film. Most of these trace back to substrate surface, adhesive laydown, cure or tension rather than the metallic material itself.
What causes pinholes in cold foil stamping? +
Pinholes usually indicate adhesive starvation or contamination. Worn or plugged anilox cells, dust on the web, poor wetting on sealed stock and static attracting debris all produce small unfoiled dots inside otherwise clean metallic areas.
Why does cold foil ghosting happen? +
Ghosting is generally caused by adhesive carryover, unstable tension or a plate and roller condition that repeats the image at a fixed interval. Cleaning contact surfaces and stabilising tension resolves most cases before any material change is needed.
Why is cold foil not transferring cleanly? +
Incomplete transfer points to insufficient adhesive film weight, weak UV cure or press speed above the transfer window. Confirm lamp output and laydown first, then reduce speed in steps and observe whether coverage recovers.
How do I know if the problem is the adhesive or the foil? +
Run the same artwork with a known-good adhesive batch and again with a different foil roll, changing one variable at a time. If the defect follows the adhesive batch or cure setting, it is a process issue; if it follows the roll, request a material review.
Why does cold foil wrinkle during production? +
Wrinkles come from unstable web tension, damaged roll edges, roller misalignment or excessive nip pressure. Inspect the roll edge before mounting, check roller parallelism and record tension at start-up, at speed and during deceleration.
What photos should I send for defect diagnosis? +
Send one overview photo showing the defect across the sheet or web, and one macro photo under raking light or magnification. Include the substrate, press settings, adhesive type, anilox specification, foil reference and running speed with the images.
When should I request a cold foil sample kit? +
Request a kit when defects repeat across different substrates, when qualifying a new substrate or adhesive, or when a brand owner requires approval before production. Testing grades side by side separates a material issue from a process issue quickly.
Need help diagnosing a cold foil defect?
Send clear defect photos, substrate details, adhesive information, anilox specification, foil effect, press speed and the point where the defect appears. CFS can help review the likely cause and recommend a suitable foil or sample test.
Request a defect diagnosis or request a cold foil sample kit.