| 摘要 |
PROBLEM TO BE SOLVED: To obtain a lightweight calcium silicate board improved in interlaminar mechanical strength through diminishing voids due to excess water and reducing entrained air by compounding a stock slurry containing a siliceous stock, calcareous stock and reinforcing fiber with an addition stock comprising cement, aluminum compound stock, anhydrous gypsum stock in specified proportions followed by subjecting the resultant slurry to papermaking process to afford a green sheet which, in turn, is put to hydrothermal synthesis. SOLUTION: This lightweight calcium silicate board is obtained by the following process: a slurry containing a total of 100 pts.wt. of the above stocks is compounded with 10-100 pts.wt. of the above-mentioned addition stock; wherein part of the stocks is compounded with the addition stock to effect formation of ettringite in the resultant slurry; the slurry is held at 25-50 deg.C for 10-60 min until it is subjected to papermaking process; by the way, ettringite is made from cement, aluminum compound stock, anhydrous gypsum stock and water, being shown by the molecular formula: 3CaO.Al2O3.3CaSO4.32H2O, being left in the form of needle crystal, after filtration, on the thin film resulting from the papermaking process; these thin films are laminated together into a green sheet which is improved in adhesion owing to crystal entanglement interlaminarly; the green sheet is subsequently put to hydrothermal synthesis to effect ettringite crystal decomposition, thereby contributing to the lightweightness of the objective calcium silicate board. |
