The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 04, 2014
Filed:
Mar. 26, 2012
Volker Jurgens, Kirchhundem, DE;
Janine Siekman, Bergisch Gladbach, DE;
Siegfried Blumel, Ratingen, DE;
Alexander Breyder, Leverkusen, DE;
Volker Schmitt, Leichlingen, DE;
Volker Jurgens, Kirchhundem, DE;
Janine Siekman, Bergisch Gladbach, DE;
Siegfried Blumel, Ratingen, DE;
Alexander Breyder, Leverkusen, DE;
Volker Schmitt, Leichlingen, DE;
Kronos International, Inc., Leverkusen, DE;
Abstract
The invention relates to a method for the surface treatment of a titanium dioxide with aluminum phosphate and hydrous aluminum oxide that leads to pigments with improved greying resistance, while simultaneously maintaining good brightness and opacity. The method is characterized in that phosphoric acid is initially added to a TiOsuspension with a pH value of at least 8, in which context the pH value drops to 3 or below. An alkaline aluminum compound is subsequently added, in which context the pH rises to at least 5, after which an acid aluminum compound is added, as a result of which a pH value of 4.5 to 7 is obtained. The pigment manufactured by the method according to the invention is eminently suitable for use in decorative laminating paper.