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:
Sep. 05, 2000
Filed:
Mar. 31, 1995
John F Krumwiede, Cheswick, PA (US);
Anthony V Longobardo, Butler, PA (US);
Larry J Shelestak, Bairdford, PA (US);
PPG Industries Ohio, Inc., Cleveland, OH (US);
Abstract
The present invention provides a glass composition having a neutral gray color and a luminous (visible) transmittance within a range that allows the glass to be used in the forward vision areas of a vehicle. The base glass is a soda-lime-silica composition and iron, cobalt, selenium and/or nickel are added as colorants. In one particular embodiment of the invention which is essentially nickel-free, a neutral gray colored glass with a luminous transmittance (C.I.E. illuminant A) of 60% and higher at a thickness of 3.9 millimeters may be attained by using as colorants: 0.30 to 0.70 wt. % Fe.sub.2 O.sub.3, no greater than 0.21 wt. % FeO, 3-50 PPM CoO and 1-15 PPM Se, and preferably 0.32 to 0.65 wt. % Fe.sub.2 O.sub.3, 0.065 to 0.20 wt. % FeO, 5 to 40 PPM CoO and 1 to 9 PPM Se. In an alternate embodiment of the invention which includes nickel oxide as a colorant, a neutral gray colored glass with a luminous transmittance of 60% and higher at a thickness of 3.9 millimeters may be attained by using 0.15 to 0.65 wt. % Fe.sub.2 O.sub.3, no greater than 0.18 wt. % FeO, 15-55 PPM CoO, 0-5 PPM Se and 25-350 PPM NiO as colorants, and preferably 0.17 to 0.60 wt. % Fe.sub.2 O.sub.3, 0.04 to 0.16 wt. % FeO, 20 to 52 PPM CoO, 0 to 3 PPM Se and at least 50 PPM NiO.