THE USE OF PHOTOETCHED SCREENS IN A CELLULOSE MILLING APPLICATION
Publication Date: 2009-Oct-13
The IP.com Prior Art Database
Keywords: Cellulose ether derivative processing; mechanical separation of cellulose particles; improved cutting mill discharge screens; screens produced by metal etching.
Keywords: Cellulose ether derivative processing; mechanical separation of cellulose particles; improved cutting mill discharge screens; screens produced by metal etching
The process to derivative cellulose to cellulose ethers commonly requires the cellulose to be ground from its bulk form (ex. sheets or rolls) into finer particles. The particle size of the ground cellulose impacts the physical properties (ex. density) of the cellulose ether derivative. The process to reduce cellulose into finer particles is typically done with a cutting mill. The particle size of the ground cellulose is determined by the screen limiting the discharge from the cutting mill.
A wide variety of screen materials may be used in this application. Examples include screens produced from woven metal wires and solid perforated metal sheets. Performance criteria for these screens include particle size distribution of the ground cellulose, the throughput or rate of the cellulose through the grinder, and the reliability or mechanical integrity of the screen. These criteria are partly a function of the size of the screen opening, the amount of open area, the sheet thickness, and the process used to create the perforations or openings.
Perforated screens produced by photoetching (ex. MicroEtch Screens available from Tech-Etch, Inc.) have been found to be advantageous in t...