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:
Feb. 23, 1988
Filed:
Dec. 12, 1986
Klaus Horn, Hofheim/Ts, DE;
Georg Sader, Huenstetten, DE;
Hans-Joachim Schulz, Wiesbaden, DE;
Michael Roethe, Wiesbaden, DE;
Hoechst Aktiengesellschaft, Frankfurt am Main, DE;
Abstract
To produce a standard calibration and test element for the calibration and testing of reading and measuring instruments for bar codes and other test scales, a copper coating is applied to a ceramic substrate in a chemically depositing copper bath and degreased, and a photoresist coating is subsequently applied which is exposed through an exposure mask. This mask carries an image of the radiation-transparent and radiation-opaque regions of a pattern to be transferred onto the surface of the ceramic substrate. After removal of the mask, the photoresist coating is developed, the uncovered zones of the copper coating are etched in a metal chloride solution, and the remaining photoresist coating is removed by stripping. The uncovered, etched zones of the copper coating are dyed matt black in a metal bath. Finally, the conductive tracks are provided with a protective coating. The standard calibration and test element produced in this fashion comprises a ceramic substrate 1 as a carrier which contains a proportion of 96 to 97% of Al.sub.2 O.sub.3. The thickness of the element is 0.635 to 1.270 mm and the dimensions can extend from a 20 mm edge length to a size of 100.times. 100 mm.