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US 11,732,411 B2Granted
Paper filler composition
AssigneeFiberLean Technologies Limited
InventorsJohn Claude Husband, Per Svending, David Robert Skuse, Tafadzwa Motsi
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AssigneeFiberLean Technologies Limited
InventorsJohn Claude Husband, Per Svending, David Robert Skuse, Tafadzwa Motsi
Estimating the term…
Methods of preparing partially dried or essentially completely dried compositions comprising microfibrillated cellulose and an inorganic particulate material may include microfibrillating a fibrous substrate comprising cellulose in an aqueous environment by grinding in the presence of an inorganic particulate material to form an aqueous composition comprising microfibrillated cellulose and inorganic particulate material, wherein the fibrous substrate comprising cellulose has a Canadian Standard freeness equal to or less than 450 cm, wherein the fibrous substrate to the inorganic particulate material are in a ratio of about 99.5:0.5 to about 0.5:99.5, and wherein the microfibrillated cellulose has a fibre steepness of from about 20 to about 50; by treating the aqueous composition comprising microfibrillated cellulose and inorganic particulate material to remove at least a portion or substantially all of the water of the aqueous composition to form a partially dried or essentially completely dried composition comprising microfibrillated cellulose and inorganic particulate material.
A method for preparing an aqueous suspension comprising microfibrillated cellulose, the method comprising a step of microfibrillating a fibrous substrate comprising cellulose in an aqueous environment by grinding in the presence of a grinding medium, which is to be removed after completion of grinding and wherein the grinding is carried out in the absence of added grindable inorganic particulate material, wherein the microfibrillated cellulose has a fibre steepness of from about 20 to about 50 and the grinding is performed in a tower mill or a screened grinder, and wherein the grinding medium is present in an amount of at least about 10% by volume of the aqueous environment, wherein the fibrous substrate comprises cellulose having a Canadian Standard freeness equal to or less than 450 cm3 and wherein the fibrous substrate comprising cellulose is a recycled pulp, or a papermill broke, or a papermill waste stream, or waste from a papermill, or a combination thereof.
Dependencies are inferred from the claim text.