Plasma coating medicament dispenser component under DC bias control

摘要

The surface of dispenser is coated by plasma deposition. At least part, but preferably not all, of the plasma deposition is performed under DC bias control and in the substantial absence of oxygen, i.e., with oxygen content (XPS) < 10 (<2) at%. The DC bias voltage is preferably 50-800 (50-350) volts. Preferably the dispenser is an earthed can 50 (16, figure 1) with a radio frequency (RF) electrode 52 inside it. The preferred coating composition comprises a hydrocarbon, fluorocarbon, silane or siloxane. The dispenser is a pressurised metered dose inhaler (pMDI) used to produce an aerosol that can be used to treat asthma or chronic obstructive pulmonary disease (COPD).