Abstract: An in-situ foam system and process comprises the components one or more inorganic fillers A) at from 50 to 98 wt %, one or more cationic or amphoteric polymers B) at from 1 to 48 wt %, one or more surfactants C) at from 0.5 to 48 wt %, one or more crosslinkers D) capable of reacting with said polymers B) at from 0.01 to 5 wt %, one or more cell regulators E), selected from silicones, siliconates and carbon, at from 0.5 to 10 wt %, one or more additives F) at from 0 to 20 wt %, wherein the weight percentages of said components A) to F) are based on the nonaqueous fractions and the sum total of A) to F) adds up to 100 wt %.