Hermetic coating by heterogeneous nucleation thermochemical deposition
US4518628A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 17, 1984 |
| Grant date | May 21, 1985 |
| Priority date | — |
| Expiry date | Feb 17, 2004 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23C16/481
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
An optical fiber which has just been drawn from an optical preform is provided with an external hermetic coating by using a heterogeneous nucleation thermochemical deposition technique. This technique involves passing the fiber through a reaction zone which contains a gaseous medium that includes a reactant which decomposes, or a mixture of reactants which chemically react, at a predetermined temperature to form the material of the coating. Only the fiber but not the gaseous medium surrounding the same is heated to the predetermined temperature, especially by directing radiation onto the exposed circumferential surface of the fiber, so that the decomposition or the chemical reaction takes place directly on the exposed surface of the fiber rather than in the gaseous medium, accompanied by simultaneous deposition of the coating material on the exposed surface of the fiber. The resulting fiber with hermetic coating can then be provided with an additional polymer coating layer. The apparatus for performing this technique includes a reactor including a transparent wall which circumferentially bounds a reaction chamber constituting the reaction zone, and a heating arrangement including t…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.