Mineral wool felt prodn. - by treating fibre with polymeric phosphate, which is water-sol. before conversion to sheet, useful for high temp. insulation

摘要

Prodn. of a mineral wool felt involves producing mineral wool fibres (I) in a fibre sepn. aggregate, adding water and a water-soluble polymeric phosphate (II) and converting to sheet form. (II) may contain linear, branched and/or cyclic condensed phosphate units, pref. with an average chain length of ring size of over 3 phosphate units. Pref. (II) are linear phosphates with an average of 7 phosphate units and mixt. of phosphates with average chain length or ring sizes of 3-6 and with more than 7 phosphate units, adjusted to a pH not damaging the mineral fibres, esp. to pH 6-8. (II) are in the form of alkaline earth and/or alkali, esp. Na salts. USE/ADVANTAGE - (II) acts as binder for (I). The felt is useful for insulation, esp. for high temp. applications, since it has good strength and contains little or no material leading to odour emission when first heated, in contrast to felts impregnated with organic additives and thermosetting resins.