Resources Contact Us Home
Browse by: INVENTOR PATENT HOLDER PATENT NUMBER DATE
 
 
Process for preparing ultra-white alumina trihydrate










Image Number 3 for United States Patent #5342485.

A process for preparing an ultra-white alumina trihydrate having a G.E. brightness of at least about 98%. The product is alumina trihydrate that has been rehydrated with coprecipitation, and the crystal phase of the product is primarily gibbsite in thin platelet form having a ratio of thickness to diameter of about 0.2 to about 0.3. The product is prepared by flash activation of a white initial alumina trihydrate, addition of the activated material to a purified sodium aluminate liquor having an alumina to caustic ratio of about 0.5, and rehydrating and precipitating the alumina at ambient temperature under agitation for about 48 hours, followed by washing and drying of the resulting precipitate. The material is especially useful as a filler or coating in papermaking, and it can be substituted for a portion of titanium dioxide pigment in the ratio of 1:1, and can be combined with titanium dioxide as a pigment mixture, either in slurry form or in dry form. The pigment mixture is added to the papermill machine chest to enhance optical properties beyond those achieved by either pigment alone.








 
 
  Recently Added Patents
High conductive water-based silver ink
Call admission control method and system
Push mechanism for efficiently sending aggregated data items to client
Adhering composition and method of applying the same
Coordinated garbage collection for raid array of solid state disks
Real-time pricing of shipping vendors
Mobile application for calendar sharing and scheduling
  Randomly Featured Patents
Weapon
Stripper roller manufacturing method
Method of aligning two bushings in a bore
Cell placement taking into account consumed current amount
Dynamic range extender apparatus, system, and method for digital image receiver system
Water blocker for wiper system
Multiple output switching power source apparatus
Knife handle
Image processing device
Medical x-ray imaging apparatus with a handlebar for patient support