Cailong

BOPP AlOx Film defects are easier to diagnose when every mark is mapped by lane, machine direction and repeat distance. A single photograph shows appearance; a roll map shows whether the cause follows the film, an edge, a roller circumference or one converting lane.

An AlOx Film Supplier can investigate more effectively when the converter supplies the roll number, unwind direction, coated-side orientation, first defective meter and defect interval. Cailong positions BOPP AlOx for transparent barrier and PP-oriented structures, so protecting the oxide layer through conversion is part of the approval task.

Separate Random Marks from Repeat Patterns

Random isolated spots may point to contamination or handling. A defect that repeats at a fixed machine-direction interval may correspond to a roller, nip or guide. A continuous line may indicate a scratch source, while a problem confined to one edge can indicate alignment, tension or contact conditions.

Mark the web before slitting and keep samples from the left, center and right lanes. If the pattern changes after printing or lamination, compare samples from each stage instead of sending only the final pouch.

Map Appearance and Barrier Separately

A visible mark does not automatically prove barrier failure, and a barrier defect may be difficult to see. Record optical observations, bond condition and OTR or WVTR results as separate fields. Use matched test conditions and identify whether the specimen is incoming film, cured laminate, flexed laminate or finished pouch.

For a possible BOPP / BOPP-AlOx / CPP structure, document which surface is printed, which surface contacts adhesive and how the web travels through each nip. This allows the team to connect a defect lane with a real contact point.

Preserve Evidence before Adjusting the Line

Changing tension, temperature and pressure at the same time can hide the cause. Freeze the original settings, retain a reference roll and change one factor per trial. Photograph the defect against a scale and label the roll position on every retained sample.

Send Cailong the defect map, laminate structure, processing sequence, machine settings and barrier results before requesting a replacement grade. The evidence can distinguish a material-selection issue from local damage introduced during converting.