Technical guide · Qualification
How to evaluate cleaning materials before production use
Qualification is a sequence of gates, not a single trial. Each gate answers a question with a defined method, and only a material that passes all of them should reach production.
Key takeaways
- Write the acceptance criteria before running any trial.
- Use bench checks to eliminate, not to approve.
- Pilot runs must cover real production variation.
- Release requires process, quality and production sign-off.
- Qualification ends with a specification and change-control clause.
1. Define the requirement
State the cleaning job, the roll material, the contamination, the line format, the cleaning method and the downstream sensitivity. Without this, the trial has no reference and any result is open to interpretation. Convert the requirement into measurable criteria: what must be removed, what must not remain, what must not be damaged and what handling is acceptable.
2. Documentation gate
- Technical data sheet with parameters, methods and tolerances.
- Safety data sheet where applicable.
- Lot identification and traceability statement.
- Change-notification policy.
- Statement of what the supplier does and does not claim.
A material without basic documentation should not proceed to a line trial, because a successful trial cannot be converted into a reproducible specification.
3. Bench evaluation
Bench checks compare candidates under controlled conditions: pickup, release, lint, wet strength and compatibility with a representative surface. Their purpose is to eliminate clearly unsuitable materials and to rank the remainder. They do not predict line performance and should not be used as approval.
Keep the bench method fixed across candidates. If the pressure, contact time or surface changes between samples, the comparison is invalid.
4. Pilot and line trial
- Clean the roll to a defined baseline with the current method.
- Run the candidate under production-representative parameters.
- Inspect the roll immediately and after a defined interval.
- Check residue with the agreed method.
- Repeat across the variation the line sees, including a product change if relevant.
- Record the lot, parameters, observations and results.
A trial that only covers a clean roll at low speed does not represent production. The most common qualification failure is a material that works in the trial and fails after several hours of running.
5. Release criteria and sign-off
Release criteria should cover the cleaning result, residue, lint, roll surface condition, handling, packaging and documentation. Each criterion needs a method and a limit. Production sign-off is essential because a material that meets the technical criteria but slows changeover or is difficult to handle will not be used as intended.
6. Convert to a controlled specification
The final step is a specification that can be ordered and audited: substrate, dimensions, loading, packaging, test methods, acceptance limits, shelf life and change control. Include the approved production site and the notification requirement for any change.
Re-qualify when the material, the liquid, the production site, the roll or the cleaning method changes. A qualification is tied to the conditions under which it was obtained.
Qualification is not a one-time event
A material qualified two years ago under a different recipe or roll condition may no longer be valid. Build periodic review into the supplier agreement rather than assuming the original result still applies.
Frequently asked questions
Can a bench test replace a line trial?
No. A bench test can eliminate candidates that clearly fail, but it cannot reproduce roll temperature, contact pressure, line speed or the real contaminant load. The line trial remains the decision point.
How long should a pilot run last?
Long enough to cover the variation the line actually sees: a full shift, a product change, or the interval between cleanings. A short run on a clean roll can miss a failure that appears after several hours.
What are release criteria?
The measured conditions that must be met before the material is used in production: cleaning result, residue, lint, handling, packaging condition and lot documentation. They should be written before the trial, not after it.
Who should sign off?
The functions that own the risk: process engineering, quality and production. A material that passes technically but disrupts changeover or handling has not passed the full evaluation.
Next step
Build a qualification plan with us
Share your line conditions and acceptance criteria. We will propose the trial sequence and the data we can provide at each gate.
Typical response time: one business day. Your details stay confidential.