Calcined kaolin clay filler pigment for enhancing opacity and printing properties of newsprint and mechanical papers
Patent 5011534 Issued on April 30, 1991. Estimated Expiration Date: 
February 14, 2010. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
February 14, 2010. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 3372043 Anhydrous kaolin clay pigment and method of preparation Kaolin calciner waste heat and feed recovery system and method Patent #: 4717559 InventorsAssigneeApplicationNo. 479793 filed on 02/14/1990US Classes:106/416, Clay containing or derived therefrom106/485, Special process of pelletizing or agglomerating or product106/486, Clay or material derived therefrom containing162/181.6, Silicon containing additive other than clay162/181.8, Clay501/144, Kaolin (e.g., ball clay, fire clay, etc.) containing501/145Clay pretreatmentExaminersPrimary: Group, KarlInternational ClassC04B 014/10AbstractA low-abrasion calcined kaolin opacifying pigment composed of particles in the size range of about 70 to 84% by weight finer than 2 microns and having a color defined by Hunter Trisitimulus values of "L" within the range of 92 to 94, "a" within the range of + 1.0 to + 2.2 and "b" within the range of +6.4 to + 7.5. The pigment is produced by novel wet processing including high solids degritting of a high iron, high titania content Tertiary kaolin without conventional fractionation, bleaching and dewatering to isolate a fine particle size fraction, followed by spray drying, pulverization, calcination and repulverization. | |
