The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 18, 1978
Filed:
Aug. 20, 1976
Ernst Zehender, Ottenbronn, DT;
Bernhard Blaich, Stuttgart, DT;
Helmut Stein, Ditzingen, DT;
Karl Kerner, Gerlingen, DT;
Robert Bosch GmbH, Stuttgart, DT;
Abstract
The reflectors, for example for automotive vehicle head lamps are reflectorized by evaporating aluminum thereon in a vacuum vessel at a vacuum of about 10.sup.-7 bar; thereafter, and without removing the reflectors, a gaseous monomer is introduced raising the pressure to about 5 .times. 10.sup.-6 bar to deposit a protective layer by polymerization from the gaseous phase. The monomer gases, preferably, are low molecular weight siloxanes having methyl-, vinyl- or phenyl groups, preferably hexamethyldisiloxane (HMDS), or methyl-, vinyl- or alkoxy silanes, preferably vinyltrimethylsilane (VTMS), polymerization being accelerated and ensured by an electrical discharge generated within the vessel by a heated electron emitter placed at a negative voltage with respect to the reflector blanks. After polymerization, the layer is rendered hydrophilic by treatment with oxygen at a pressure of about 10.sup.-2 to 10.sup.-3 m bar to form an organosilicon polymeric protective layer which is inherently hydrophobic and has a hydrophilic surface.