摘要 |
<p>Increased elasticity of a laminate is obtained by adding 5-20% by weight of a blocked polyetherurethane component from a reaction product of polyethylene glycol, polypropylene glycol and p-nonylphenol with toluene-2,4-diisocyanate having the following composition: -polyethylene glycol 15-20% by weight -polypropylene glycol 50-60% by weight -toluene-2,4-diisocyanate 8-12% by weight -nonylphenol 10-15% by weight - in the manufacture of a fire resistant laminate based on a cellulose-containing substrate material and an impregnating varnish made up of a phenol-resol with additives of plasticizers and flame retardants. A copper-laminated hard paper made of this phenolic resin laminate is distinguished by reduced punching resistance and stripping resistance.</p> |