Optical brighteners for adhesives and hot melt
Adhesive whiteness is a proxy for freshness. A hot melt that has yellowed in the pot reads as degraded even when it bonds perfectly, and a brightener buys back that perception at a very low addition rate.
What the grade has to survive
Four things that decide the choice
- Survives hot melt pot temperature and residence time
- Keeps EVA and PSA systems visually fresh
- No effect on open time or bond strength at working dosage
- Suits clear as well as filled adhesive
These are the constraints we work through with customers on this application. Everything on this page traces back to the published data for the grades listed below.
Grades for adhesives
Optical brightener OB
The workhorse of the benzoxazole family and the grade most plastics buyers are matching when their specification says Uvitex OB or Tinopal OB.
Optical brightener KCB
A naphthalene-bridged bisbenzoxazole developed for EVA foam, and still the first choice for footwear midsoles.
Optical brightener FP-127
A methoxy-substituted distyryl biphenyl built for soft PVC.
Background reading on adhesives
Enhancing Performance with OBA for Hot Melt Adhesive
Hot melt adhesives (HMAs) are versatile bonding materials widely used across industries such as packaging, woodworking, textiles, and electronics. Composed
Enhancing Adhesive Quality and Appearance with OBA for Adhesives
Adhesives play a vital role in countless industries-from household use and packaging to automotive, construction, and electronics. However, maintaining high
Related markets
Plastics
In a polymer the brightener has to dissolve into the melt, survive the process temperature and then stay put.…
Paints, coatings & inks
Coatings split cleanly into two camps. Oil-based and solvent systems take OB, which dissolves in the resin…
PVC compounding
PVC is the one polymer where a brightener rarely travels alone. The same compound needs a heat stabiliser to…
Other application briefs
White masterbatch
A masterbatch concentrates the brightener twenty to a hundred times over the let-down dosage, so…
PVC foam board
Foam board yellows for two reasons at once - thermal stress during expansion and the intrinsic cast…
PVC pipe & profile
Pipe and profile are extruded hot, run long, and are judged on appearance for decades in sunlight.…
PP woven bags
Woven sack tape is drawn hot and thin, often from a resin blend that includes recycled material.…
EVA shoe soles
Footwear foam is the application KCB was developed for. The expansion step destroys a poorly chosen…
Blown film
In film the brightener has to raise apparent whiteness without touching clarity, and it has to do…
Send us the adhesives brief
Substrate, process temperature, whiteness target and trial quantity. That is everything we need to name a grade.