Kaolin products and their production

A method of producing a kaolin particulate material suitable for use as a super-calendered filler, said method comprising:

• (a) preparing an aqueous feed suspension of kaolin;
• (b) treating the kaolin of the feed suspension by attrition grinding in a grinding vessel using grinding media granules;
• (c) delivering an aqueous suspension of the kaolin ground in (b) to a particle size classifier and separating the kaolin of the suspension into a coarse fraction and a fine fraction;
• (d) returning an aqueous suspension of the coarse fraction produced in (c) to the grinding vessel to be further attrition ground;
• and
• (e) extracting an aqueous suspension of the fine fraction produced in (c) as a product suspension;
• wherein the kaolin of the feed suspension in (a) is such that not more than 30% by weight has a particle size less than 2 μm and not more than 30% by weight has a particle size greater than 10 μm;
• and
• wherein the kaolin of the product suspension produced in (e) has a mean particle size ranging from 0.9 μm to 1.6 μm, a steepness factor of at least about 32, and is such that not more than 10% by weight has a particle size greater than 10 μm and not more than 10% by weight has a particle size less than 0.25 μm.