US 7,070,656 B2 · Electrostatic coating

Abstract

The invention provides apparatus for electrostatically coating a pharmaceutical tablet core with powdered coating material. The apparatus comprises a first rotary drum (12) on which a core is held in electrical isolation from its surroundings but at a potential differecne to earth by an electrode which contacts the core. The core is carried past a coating station B at which particles of powder having an opposite potential difference to earth are held in a tray (18). The surface of the drum is held at the same potential difference to earth as the powder particles. The powder is attracted to the core, and not to the drum, coating the exposed surface of the core. The drum carries the coated core past a fusing station C at which a heater fuses the powder to form a continuous film coating. The core is then turned and transferred onto a second drum (12′) where the other surface is coated in the same way.

Claims29

Dependent claims

Apparatus for electrostatically coating electrically poorly conducting substrates, comprising:

a supply of particulate coating material,
a conveyor,
a plurality of individual locations defined over a surface of the conveyor, each adapted to receive a respective substrate,
a plurality of electrode surfaces, each positioned at a respective one of the individual locations for holding a respective substrate substantially isolated from adjacent regions of the surface of the conveyor,
the supply of particulate coating material and the electrode surfaces being arranged to hold a substrate to be coated and particulate coating material at a potential difference to each other at a coating station.

2 more elements

Dependencies are inferred from the claim text.

Facts

Application

10/739,943Filed 19 Dec 2003 · continuation

Priority

GB 9509347.219 May 1995

Published

US 2004/0177809 A116 Sep 2004

Granted

4 Jul 2006

Term ends

Not estimatedThe source records don’t support an estimate.

Classification17 codes

A61K 9/2866
Polysaccharides, e.g. gums; Cyclodextrin: cellulose; Cellulose derivatives, e.g. hydroxypropyl methylcellulose
A61J 3/005
Devices or methods specially adapted for bringing pharmaceutical products into particular physical or administering forms: coating of tablets or…
A61K 9/209
Layered tablets, e.g. bilayer tablets; Tablets of the type inert core-active coat: containing drug in at least two layers or in the core and in at…
A61K 9/2846
Obtained by reactions only involving carbon-to-carbon unsaturated bonds, e.g. polyvinyl pyrrolidone: polyacrylates

Family

PCT/GB96/01102Parent of this continuation · filed 8 May 1996

Application08/999,564Parent of this division · filed 10 Nov 1997

Application09/629,439Parent of this continuation · filed 31 Jul 2000

Application09/939,631Parent of this continuation · filed 28 Aug 2001

US 2004/0177809 A1Pre-grant publication · published 16 Sep 2004

US 6,117,479 AParent of this division

Application09/629,439Parent of this division

Application08/999,564Parent of this continuation

US 2002/0034592 A1Published application

US 7,070,656 B2This patent

From the US filing history. Foreign family members aren’t listed.

Electrostatic coating

Life of this patent

Electrostatic coating

Life of this patent

Abstract

Claims29