Slitting Machine Guide Pad Wears Less With Powder Additive

A slitting machine guide pad is the wear part the film rides on — it must stay dimensionally stable, low-friction and non-marking through long runs. Builders load these pads with filler for stiffness, but high load drives blocking, friction drift and die fouling in the pad stock. Xiangxi's BOPP/CPP film masterbatch series — powder grade, carried on silica at 0.5–3%, disperses into the filled compound to control COF and anti-block without blooming, so the guide pad wears evenly and the film is not marked.

Why slitting guide pads drift and mark

• Filler friction — high CaCO3 raises surface friction, so the pad heats and the web walks off track.
• Bloom — loose slip migrates to the pad face and transfers a film to the product.
• Wear unevenness — poorly dispersed additive gives local hard spots that score the film edge.

Guide-pad compound routes compared

Xiangxi BOPP/CPP film masterbatch series

Which grade for slitting guide pads

• powder grade — the fit for high-filler pad stocks; silica carrier matches the filler and avoids bloom.
• PP carrier grade — for a low-filler PP pad variant.
• PE carrier grade — for a CPP-based pad ply.

Processing notes

• Add the powder with the filler in the pad compound; it blends into the high-load melt.
• Start at 0.5% and set COF (ASTM D1894); filled pads often need 1–3%.
• Run a wear and a transfer (bloom) check on a trial pad before fitting.
• Side gains: even wear, no edge scoring, clean film.

Results to verify in your own lab

• COF (ASTM D1894): lower, stable on the pad face.
• Wear rate: even across the pad, longer service.
• Bloom: no transfer to the film edge.
• Edge quality: fewer scores on the slit web.

Frequently asked questions

Will high filler score my film edge?

High CaCO3 can, but the powder grade disperses evenly and cuts local hard spots, so edge scoring drops.

Does it bloom onto the film?

No — the silica-carried additive is locked in and does not migrate to the pad face.

Will it soften the pad?

It is surface-active only; the filled compound's stiffness and dimensional stability hold.

Can I keep a high filler load?

Yes, the powder grade is made for filled stocks; confirm COF and wear on a trial pad.

How do I set dosage?

Begin at 0.5%, raise in 0.5% steps against ASTM D1894 and a wear check.

Is it suitable for film contact?

The powder grade ships with TDS and COA; confirm the limits for your film and region.