Process for producing cellulose derivatives of high bulk density and good flowability

Patent metadata

Field	Value
Publication number	US-2016256390-A1
Application number	US-201615140786-A
Country	US
Kind code	A1
Filing date	May 23, 2016
Priority date	Apr 6, 2011
Publication date	Sep 8, 2016
Grant date	—

Abstract

A particulate cellulose derivative is obtained in a process of grinding and drying a moist cellulose derivative which comprises the steps of
A) providing a cellulose derivative having a moisture content of from 60 to 95 percent, based on the total weight of the moist cellulose derivative, B) grinding and partially drying the moist cellulose derivative in a gas-swept impact mill; and C) contacting the ground and partially dried cellulose derivative with an additional amount of a drying gas outside the gas-swept impact mill.

The obtained particulate cellulose derivative has a high untapped bulk density and a good flowability.

First claim

1 .- 10 . (canceled)

11 . A particulate cellulose derivative having a median Equivalent Projected Circle Diameter (EQPC) of less than 140 micrometers, an untapped bulk density of at least 0.40 g/cm 3 and a Carr Index of 30 or less.

12 . The particulate cellulose derivative of claim 11 having a Carr Index of 25 or less.

13 . The particulate cellulose derivative of claim 11 having a median particle length of from 60 to 350 micrometers.

14 . The particulate cellulose derivative of claim 11 having an onset dissolution temperature of at least 61.5° C.

15 . A dosage form produced from
a) one or more cellulose derivatives of claim 11 , b) one or more active ingredients, and c) one or more optional adjuvants.

16 . (canceled)

17 . The particulate cellulose derivative of claim 11 being one of methyl cellulose, methyl hydroxyethyl cellulose, methyl hydroxypropyl cellulose and hydroxypropyl cellulose.

18 . The particulate cellulose derivative of claim 11 being hydroxypropyl methylcellulose.

19 . The particulate cellulose derivative of claim 11 having an untapped bulk density of at least 480 g/l.

20 . The particulate cellulose derivative of claim 18 having a Carr Index of 25 or less and a median particle length of from 60 to 350 micrometers.

Assignees

• Dow Global Technologies Llc

Inventors

• Goerlach-Doht Yvonne M
• Hermanns Juergen
• Grossstueck Marco

Classifications

• C08B11/20 Primary

  Post-etherification treatments of chemical or physical type, {e.g. mixed etherification in two steps}, including purification · CPC title

• A61K9/146 Primary

  with organic macromolecular compounds · CPC title

• C08B11/193

  Mixed ethers, i.e. ethers with two or more different etherifying groups · CPC title

• B02C13/288

  Ventilating, or influencing air circulation · CPC title

• B02C23/24

  Passing gas through crushing or disintegrating zone ({B02C15/001}, B02C23/38, B02C23/40 take precedence) · CPC title