The invention concerns an aqueous slurry comprising thermally expandable
microspheres comprising a thermoplastic polymer shell and a propellant
entrapped therein, said slurry further comprising an at least partially
water soluble polymer selected from the group consisting of gums,
celluloses, chitins, chitosans, glycans, galactans, pectins, mannans,
dextrins, polyacrylic acid, esters and amides and co-polymers thereof,
polymethacrylic acid, esters and amides and co-polymers thereof, rubber
latexes, poly(vinyl chloride) and copolymers, poly(vinyl esters) and
co-polymers, poly(vinyl alcohol), polyamines, polyetyleneimine,
polyethylene/polypropylene oxides, polyurethane, and aminoplast and
phenoplast precondensates and polyamidoamine epichlorohydrin resins. The
invention further concerns a process for its preparations, use thereof
for the production of paper or non-woven, and a process for the
production of paper or non-woven.