Sheets having a highly inorganically filled organic polymer matrix

A sheet having an inorganically filled matrix prepared by the method comprising the steps of:

• mixing together water, a water-dispersible organic polymer binder, an inert inorganic aggregate filler, and fibers to form a moldable inorganically filled mixture in which the individual components are substantially homogeneously dispersed, the inert inorganic aggregate filler having a concentration in a range from about 40% to about 95% by weight of total solids in the inorganically filled mixture, the organic polymer binder and fibers having a combined concentration in a range from about 5% to about 60% by weight of total solids in the mixture, the water having a concentration in a range from about 5% to about 50% by volume of the mixture;
• passing the inorganically filled moldable mixture between at least one pair of reduction rollers without any significant drainage of water in a liquid state from the inorganically filled moldable mixture to form a green inorganically filled sheet of a predetermined thickness that maintains its integrity as a sheet substantially free from underlying support as it exits the reduction rollers;
• and
• removing a substantial portion of the water from the inorganically filled sheet in an accelerated manner by evaporation to form the inorganically filled matrix of the sheet, the inorganically filled matrix of the sheet comprising a substantially homogeneous mixture of organic binder and aggregate filler, with the fibers being substantially homogeneously dispersed throughout the inorganically filled matrix, wherein the inorganically filled matrix has a thickness in a range from about 0.01 mm to about 1 cm and degrades after prolonged exposure to water.

A spooled sheet having an inorganically filled matrix prepared by the method comprising the steps of:

• mixing together water, a water-dispersible organic polymer binder, an inorganic aggregate filler, and organic fibers to form a moldable inorganically filled mixture in which the individual components are substantially homogeneously dispersed, wherein the inorganic aggregate filler has a concentration in a range from about 40% to about 95% by weight of total solids, wherein the organic polymer binder and organic fibers have a combined concentration in a range from about 5% to about 60% by weight of total solids in the inorganically filled mixture, and wherein the water has a concentration in a range from about 5% to about 50% by volume of the inorganically filled mixture;
• forming inorganically filled mixture between at least one pair or reduction rollers without any significant drainage of water in a liquid state from the inorganically filled moldable mixture to form a green inorganically filled sheet that maintains its integrity as a sheet substantially free from underlying support as it exits at least one pair of reduction rollers;
• drying the green inorganically filled sheet by removing a substantial portion of the water from the inorganically filled sheet by evaporation to form a substantially dried inorganically filled matrix comprising a substantially homogeneous mixture of the organic polymer binder and inorganic aggregate material, with the fibers being substantially homogeneously dispersed throughout the inorganically filled matrix, wherein the organic polymer binder and organic fibers have a combined concentration in a range from about 5% to about 60% by weight of total solids;
• and
• winding the substantially dried inorganically filled sheet onto a spool to form a spooled sheet.