Reactive PU Hotmelts solidify quickly after application, providing strong initial strength for bonds – perfect for working with no delays. They then react chemically with the moisture in the air or the materials around them to reach their ultimate high level of stability and adhesion.


The respective chemical formulations mean that reactive PU Hotmelts can adapt precisely to the requirements of the production process and the bonding point. This is thanks to their viscosity, the application window, the setting time and the time to complete chemical hardening.

Melting Application Cooling Hardening Ultimate State

OTTO did not invent reactive PU Hotmelts. But we are reinventing them to suit your requirements, perfectly adapted to your production process and what you need from the bonding point. We are also happy to work with leading manufacturers of application equipment. And, of course, in the precise quantity and form that you need.

Product Name Applications Application Window (min) Setting Time (sec.) Viscosity (mPas at 130°C) Strength Development
(N/mm2) after 1 h after 7 d
Novasil ® H 850 Assembly, assembly bonding Grout, embedding Lamination 2–3 60–120 5.000–10.000 5,7 35 can be sprayed like paint at 170°C
Novasil ® H 853 Assembly Edgefold bonding 1 10 15.000–25.000 5,8 51 short window, high initial adhesion, excellent adhesion on ABS
Novasil ® H 857 Assembly Profile wrapping 6–8 10 20.000–30.000 4,3 35 long processing window on slow machines
Novasil ® H 859 General bonding 13 780 approx. 5.000 2 32 Low emission (unlabelled), very low application temperature (70°C)
Novasil ® H 863 Various bonds 1 30 3.500–6.500 5,4 35 low viscosity, short window
Novasil ® H 865 Flat lamination Bonds that require long windows 20 5 approx. 10.000 1,7 31 long window
Novasil ® H 867 Flat lamination > 60 5 approx. 8.000 - 17 very long window

Our reference products show the range of options opened up to you through the world of OTTO reactive PU Hotmelts. Various properties in terms of viscosity, application time, physical curing rates and ultimate strength.