Abstract: An object of the present invention is to provide an etching method that enables control of etching of a conductive polymer using a specific cerium (IV) compound to be carried out simply and easily, thus ensuring that etching is carried out stably, and to provide a substrate having a conductive polymer that has been etched by the etching method. The etching method of the present invention includes an etching step of etching a conductive polymer using an etching liquid containing a specific cerium (IV) compound, an analysis step of analyzing the etching liquid by at least one analysis means selected from the group consisting of oxidation-reduction potential measurement, oxidation-reduction titration, and electrical conductivity measurement, and a control step of controlling the etching step according to the results obtained in the analysis step.

Abstract: A print inspecting apparatus capable of identifying a page of a form corresponding to a clipped image without requiring a special barcode or printing, is provided. A print inspecting apparatus 1 acquires correct solution information which is associated with plural inspection areas EF and barcode area BC in one page and page information, and includes an inspection server 31 which sets plural areas to be clipped from the image corresponding to the inspection areas, a conveying motor which conveys the form in one direction; line scan cameras which read the image of the form, and inspecting terminals 32 which clips plural of areas from the image read by the camera to decode the image, and determine that the character string in the plurality of inspection areas falls under that of what page in the form, based on the decoded character string in the inspection area and the correct solution information.

Abstract: The present invention provides etching solution for alloy steel such as stainless steel using ferric chloride, in which ferric chloride can be regenerated without carrying out an operation of removing chromium and nickel and while suppressing an increase in the amount of the etching solution, and an etching method using the etching solution. The etching solution is etching solution comprising ferric chloride and chromium ions or nickel ions, or etching solution comprising ferric chloride, chromium ions and nickel ions and comprising each type of metal ions in a metal composition ratio approximately equal to a metal composition ratio in alloy steel to be etched. The etching method is a method for etching alloy steel with etching solution comprising ferric chloride and comprising each type of metal ions in a metal composition ratio approximately equal to a metal composition ratio in the alloy steel.

Abstract: An austenitic stainless steel for use for high temperature concentrated sulfuric acid which comprises, on weight basis, 0.04% or less of C, 5-7% of Si, 2% or less of Mn, 15-25% of Cr, 4-24% of Ni, 0.01-1.07% of Pd and the rest consisting of Fe and unavoidable contaminant materials. By the incorporation of small amount of palladium in a basal austenitic stainless steel containing the essential three elements of Cr, Ni and Si, a superior corrosion resistance against highly concentrated high temperature sulfuric acid is attained.