A method is provided for subtractively processing a layer of etchable material formed over an electrically conductive surface region of a workpiece. The workpiece is immersed in a liquid solution, generally but not exclusively a conductive solution, that comprises an etchant for the etchable material, so that etching of the etchable material is initiated. An electric circuit is connected to include a control electrode, a reference electrode, and the electrically conductive surface region of the workpiece. The electric circuit is used to monitor the development process dynamically at each of a plurality of intervals during the etching. The etching is terminated when the electrochemical signal satisfies a criterion indicating that the etching is complete.

The present invention employs a compound represented by the following formula (1) and/or a resin comprising the compound as a constituent: ##STR00001## wherein R.sup.1 is a 2n-valent group of 1 to 60 carbon atoms or a single bond; R.sup.2 to R.sup.5 are each independently a linear, branched, or cyclic alkyl group of 1 to 10 carbon atoms, an aryl group of 6 to 10 carbon atoms, an alkenyl group of 2 to 10 carbon atoms, an alkoxy group of 1 to 30 carbon atoms, a halogen atom, a thiol group, a hydroxy group, or a group in which a hydrogen atom of a hydroxy group is replaced with an acid dissociation group, provided that at least one selected from R.sup.2 to R.sup.5 is a group in which a hydrogen atom of a hydroxy group is replaced with an acid dissociation group; m.sup.2 and m.sup.3 are each independently an integer of 0 to 8; m.sup.4 and m.sup.5 are each independently an integer of 0 to 9, provided that m.sup.2, m.sup.3, m.sup.4, and m.sup.5 are not 0 at the same time; n is an integer of 1 to 4; and p.sup.2 to p.sup.5 are each independently an integer of 0 to 2.

The present invention employs a compound represented by the following formula (1) and/or a resin comprising the compound as a constituent: ##STR00001## wherein R.sup.1 is a 2n-valent group of 1 to 60 carbon atoms or a single bond; R.sup.2 to R.sup.5 are each independently a linear, branched, or cyclic alkyl group of 1 to 10 carbon atoms, an aryl group of 6 to 10 carbon atoms, an alkenyl group of 2 to 10 carbon atoms, an alkoxy group of 1 to 30 carbon atoms, a halogen atom, a thiol group, a hydroxy group, or a group in which a hydrogen atom of a hydroxy group is replaced with an acid dissociation group, provided that at least one selected from R.sup.2 to R.sup.5 is a group in which a hydrogen atom of a hydroxy group is replaced with an acid dissociation group; m.sup.2 and m.sup.3 are each independently an integer of 0 to 8; m.sup.4 and m.sup.5 are each independently an integer of 0 to 9, provided that m.sup.2, m.sup.3, m.sup.4, and m.sup.5 are not 0 at the same time; n is an integer of 1 to 4; and p.sup.2 to p.sup.5 are each independently an integer of 0 to 2.

A lithographic printing plate precursor including an image recording layer containing an infrared absorber represented by Formula I, on a support, and a method of producing a lithographic printing plate and a lithographic printing method using the lithographic printing plate precursor. ##STR00001##

A resist composition is disclosed which comprises a perovskite material with a structure having a chemical formula selected from ABX.sub.3, A.sub.2BX.sub.4, or ABX.sub.4, wherein A is a compound containing an NH.sub.3 group, B is a metal and X is a halide constituent. The perovskite material may comprise one or more of the following components: halogen-mixed perovskite material; metal-mixed perovskite material, and organic ligand mixed perovsikte material.

A method for processing a photosensitive flexographic printing plate having an aqueous-processable photopolymer. A main processing unit is used to develop a relief image by removing unexposed photopolymer using an aqueous processing solution including a first dispersing agent while the photosensitive flexographic printing plate is being subjected to mechanical cleaning. Used aqueous processing solution containing the removed photopolymer is returned back into a processing solution tank. A secondary processing unit is used to wash the developed relief image with secondary aqueous processing solution including a second dispersing agent to remove debris from the developed relief image. Used secondary aqueous processing solution containing the removed photopolymer is directed into the processing solution tank. A portion of the aqueous processing solution from the processing solution tank is removed to keep a volume of aqueous processing solution in the processing solution tank below a predefined maximum volume.

A resist composition including: a compound including an anion moiety and a cation moiety and represented by the following Formula (bd1); and an organic solvent having a hydroxyl group in which Rx.sup.1 to Rx.sup.4 each represent a hydrocarbon group or a hydrogen atom, or may be bonded to each other to form a ring structure; Ry.sup.1 and Ry.sup.2 each independently represent a hydrocarbon group or a hydrogen atom, or may be bonded to each other to form a ring structure; Rz.sup.1 to Rz.sup.4 each represent a hydrocarbon group or a hydrogen atom, or may be bonded to each other to form a ring structure; at least one of Rx.sup.1 to Rx.sup.4, Ry.sup.1 and Ry.sup.2 and Rz.sup.1 to Rz.sup.4 has an anionic group; and M.sup.m+ represents an organic cation) ##STR00001##

A resist composition including: a compound including an anion moiety and a cation moiety and represented by the following Formula (bd1); and an organic solvent having a hydroxyl group in which Rx.sup.1 to Rx.sup.4 each represent a hydrocarbon group or a hydrogen atom, or may be bonded to each other to form a ring structure; Ry.sup.1 and Ry.sup.2 each independently represent a hydrocarbon group or a hydrogen atom, or may be bonded to each other to form a ring structure; Rz.sup.1 to Rz.sup.4 each represent a hydrocarbon group or a hydrogen atom, or may be bonded to each other to form a ring structure; at least one of Rx.sup.1 to Rx.sup.4, Ry.sup.1 and Ry.sup.2 and Rz.sup.1 to Rz.sup.4 has an anionic group; and M.sup.m+ represents an organic cation) ##STR00001##

A sulfonic acid derivative, wherein the sulfonic acid derivative is represented by the following general formula (1):

R.sup.1COOCH.sub.2CH.sub.2CFHCF.sub.2SO.sub.3.sup.−M.sup.+  (1)

where: R.sup.1 represents a monovalent organic group having carbon number of 1 to 200, having at least one hydroxyl group and optionally having a substituent other than the hydroxyl group; and M.sup.+ represents a counter cation.

A radiation-sensitive resin composition includes: a resin containing a structural unit A represented by formula (1); at least one radiation-sensitive acid generator selected from the group consisting of a radiation-sensitive acid generator represented by formula (2-1) and a radiation-sensitive acid generator represented formula (2-2); and a solvent. At least one R.sup.3 is an acid-dissociable group; and R.sup.41 is a hydrogen atom or a protective group to be deprotected by action of an acid. At least one of R.sup.f1 and R.sup.f2 is a fluorine atom or a fluoroalkyl group; R.sup.5a is a monovalent organic group having a cyclic structure; X.sub.1.sup.+ is a monovalent onium cation; R.sup.5b is a monovalent organic group, and X.sub.2.sup.+ is a monovalent onium cation whose atom having a positive charge is not an atom forming a cyclic structure. ##STR00001##