COATING METHOD

摘要

A method for coating a substrate surface such as a syringe part by PECVD is provided, the method comprising generating a plasma from a gaseous reactant comprising an organosilicon precursor and optionally an oxidizing gas by providing plasma-forming energy adjacent to the substrate, thus forming a coating on the substrate surface by plasma enhanced chemical vapor deposition (PECVD). The plasma-forming energy is applied in a first phase as a first pulse at a first energy level followed by further treatment in a second phase at a second energy level lower than the first energy level. The lubricity, hydrophobicity and/or barrier properties of the coating are set by setting the ratio of the O2 to the organosilicon precursor in the gaseous reactant, and/or by setting the electric power used for generating the plasma.

主权项

1. A method for preparing a lubricity coating on a plastic substrate, in which the substrate is a syringe, the method comprising:
(a) providing a gas comprising:
i. an organosilicon precursor,ii. optionally an oxidizing gas, andiii. a diluent gas in the vicinity of the substrate surface; and (b) generating plasma in the gas by providing plasma-forming energy adjacent to the plastic substrate, thus forming a coating on the substrate surface by plasma enhanced chemical vapor deposition (PECVD); in which: the plasma-forming energy is applied in a first phase as a first pulse at a first energy level followed by further treatment in a second phase, at a second energy level lower than the first energy level, and reduces the breakout force, Fi, of the syringe, compared to the breakout force of a similar syringe that has only been treated at the second energy level; the resulting lubricity coating has an atomic ratio SixOxCyHz or Siw(NH)xCyHz wherein w is 1 as measured by X-ray photoelectron spectroscopy (XPS), x is from about 0.5 to about 2.4 as measured by XPS, y is from about 0.6 to about 3 as measured by XPS, and z is from 2 to about 9 as measured by Rutherford backscattering spectrometry (RBS); and the lubricity coating has a lower frictional resistance than the uncoated surface.