| 摘要 |
1527077 Acid stabilized paper filler composition ASSOCIATED PORTLAND CEMENT MFGS Ltd 17 Nov 1975 [15 Nov 1974] 49657/74 Heading C3U [Also in Division D2] A filler composition for paper having improved resistance to acid over conventional fillers comprises a pigment, e.g. chalk whiting or clay, a starch phosphate and an organic polymeric retention aid, the combined weight of the starch phosphate and the organic polymeric retention aid on a solids basis being from 0À1 to 20% by weight of the pigment. Preferably the organic polymeric retention aid, which may be a polyacrylamide or polyamide, represents from 0À1 to 25% solids basis of the combined weight of starch phosphate and the retention aid. The starch phosphate may be a monoester or diester of a phosphoric acid or a water-soluble salt thereof of DS 0À002 to 1À0 in terms of bound phosphorus. The composition may be prepared as a dispersion in water. |
