The present invention refers to a mineral matter powder preparation by wet process without acrylic additive or other grinding aid additives and to Me use of said mineral matter after an optional hydrophobic treatment. Said mineral material Having superior dispersing properties.

A method for coating a paper drinking straw, an apparatus for coating a paper drinking straw, and a coated drinking straw assembly are disclosed. The apparatus includes a dipping tank containing a liquid bath for coating a straw when submerged in the liquid and a straw engagement means for submerging the straw in the bath. The method includes receiving an uncoated paper drinking straw and submerging the straw in a bath containing a water-resistant and/or a water-soluble coating. The drinking straw assembly includes an elongate tubular body and a coating that has been applied to all surfaces of the straw by submerging the body in a bath containing the coating.

A method for coating a paper drinking straw, an apparatus for coating a paper drinking straw, and a coated drinking straw assembly are disclosed. The apparatus includes a dipping tank containing a liquid bath for coating a straw when submerged in the liquid and a straw engagement means for submerging the straw in the bath. The method includes receiving an uncoated paper drinking straw and submerging the straw in a bath containing a water-resistant and/or a water-soluble coating. The drinking straw assembly includes an elongate tubular body and a coating that has been applied to all surfaces of the straw by submerging the body in a bath containing the coating.

A method for preparing an aqueous suspension may include providing a fibrous substrate comprising cellulose having a Canadian Standard freeness equal to or less than 450 cm.sup.3, and microfibrillating the fibrous substrate in an aqueous environment by grinding in the presence of a grinding medium consisting essentially of mullite. The grinding may be carried out in the absence of grindable inorganic particulate material. The grinding medium may be present in an amount of at least about 10% by volume of the aqueous environment. The microfibrillated cellulose may have a fibre steepness of from about 20 to about 50.

A method for preparing an aqueous suspension may include providing a fibrous substrate comprising cellulose having a Canadian Standard freeness equal to or less than 450 cm.sup.3, and microfibrillating the fibrous substrate in an aqueous environment by grinding in the presence of a grinding medium consisting essentially of mullite. The grinding may be carried out in the absence of grindable inorganic particulate material. The grinding medium may be present in an amount of at least about 10% by volume of the aqueous environment. The microfibrillated cellulose may have a fibre steepness of from about 20 to about 50.

The invention discloses a method of producing a filler composition to be used in paper or board production, said method comprising providing a suspension comprising calcium hydroxide and performing carbonation of the calcium hydroxide to form precipitated calcium carbonate (PCC). The invention is characterized in that starch and/or carboxy methyl cellulose (CMC) is added to the suspension during said carbonation of calcium hydroxide. The method of the invention enables an increased filler content in paper or paperboard without substantially increasing the dusting tendency or decreasing the strength of the paper or board.

The present invention refers to a process for making a calcium carbonate containing material, wherein the process includes a specific drying procedure and allows for the provision of calcium carbonate materials with reduced moisture pick-up and low porosity.

The present invention relates to a water-resistant mineral-coated cellulose-based substrate, comprising a cellulose-based substrate, and a mineral-coating layer disposed on at least one surface of said substrate, said mineral coating comprising 50-95 wt % of a particulate mineral and 5-50 wt % of a water-dispersible binder based on the total dry weight of the mineral coating, and wherein said mineral-coating layer has been subjected to grafting with a fatty acid halide. The invention further relates to a method for manufacturing the water-resistant mineral-coated cellulose-based substrate.

A coated paperboard is disclosed which includes a printable coating containing substantially no fluorochemical or wax in which the coated paperboard is fully compostable as well as repulpable, and exhibits no tendency toward blocking. The coating may be a multiple layer coating.

A coated paperboard is disclosed which includes a printable coating containing substantially no fluorochemical or wax in which the coated paperboard is fully compostable as well as repulpable, and exhibits no tendency toward blocking. The coating may be a multiple layer coating.