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:
Jan. 14, 1986
Filed:
Jun. 26, 1984
Abstract
The addition of a small quantity of ammonium chloride to an ammonium sulf etching solution results in shortening the regeneration time of the spent etching solution when air or oxygen is bubbled through it to reoxidize it, and it also results in accelerating the etching rate. The extent of this improvement deteriorates with increasing chlorine ion content, disappearing when the chlorine ion content substantially exceeds 0.4% by weight of the solution and still greater chlorine ion additions are distinctly undesirable. The electrolysis of the etching solution to remove etched-away metal cathodically produces enough oxygen at the anode to prevent any substantial evolution of chlorine from the electrolytic action on the small chlorine ion content.