Optical brighteners for EVA foam and shoe soles
Footwear foam is the application KCB was developed for. The expansion step destroys a poorly chosen brightener, and a midsole that yellows in the box is a returned order.
What the grade has to survive
Four things that decide the choice
- Tolerance of foaming and coupling agents
- Whiteness retained through expansion and cooling
- Options for PVC and TPR soles as well as EVA
- Vividness in coloured compounds, not only whites
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 eva shoe soles
Optical brightener KCB
A naphthalene-bridged bisbenzoxazole developed for EVA foam, and still the first choice for footwear midsoles.
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 FP-127
A methoxy-substituted distyryl biphenyl built for soft PVC.
Background reading on eva shoe soles
The best OBA for EVA shoe soles
EVA (ethylene-vinyl acetate) is one of the most widely used materials for shoe soles, known for its lightweight, flexible, and
Choosing the Right Optical Brightener for PVC Shoe Sole Applications
Introduction PVC foam shoe materials have become widely favored in the footwear industry thanks to their lightweight construction, excellent cushioning,
Optical brighteners for footwear
Optical brighteners are additives that are commonly used in the footwear industry to enhance the appearance of materials used in
How to choose a optical brighteners for footwear materials.
Optical brightener KCB is now widely used in EVA foam shoe materials or footwear materials, considering the stability of the optical brightener: 2.
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.…
Blown film
In film the brightener has to raise apparent whiteness without touching clarity, and it has to do…
Recycled plastics
Recyclate arrives with a yellow-grey cast that no amount of washing removes. A brightener is the…
Send us the eva shoe soles brief
Substrate, process temperature, whiteness target and trial quantity. That is everything we need to name a grade.