Xanthates as an Alternative to Dithiocarbamates and Thiazoles in Latex?

Manufacturer: We are manufacturing latex dipped products including gloves. Recently we've received feedback from the market that some of our customers are allergic to the residual dithiocarbamates and thiazole accelerators in our products. We've been advised to look into xanthates which we've never heard of or used before. Can you please give your comment and advice?

John Woon (Senior Latex Consultant): You could start by evaluating sodium isopropyl xanthate, zinc isopropyl xanthate and zinc butyl xanthate. The sodium salt is water soluble while the zinc salt is not. The soluble version is more active and gives a faster cure than the insoluble one. You could also use a combination of both.

Xanthates belong to the group of extremely fast ultra accelerators. Since they are very fast, one tends to get a narrower cure plateau and a lower cure temperature of 80 to 110ºC. You still need the usual level of ZnO.

The disadvantages of xanthate are the instability, being a very labile accelerator and the odour which can be objectional to some people.