Disclosed herein is an aqueous composition having a pH value at 55° C. in the range from 5 to 9, containing at least two different amino organophosphonic acid derivatives of formula (I)

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where residues R independently of each other are CH.sub.2—PO(OR″).sub.2, residues R′ independently of each other are alkylene residues with 2 to 4 carbon atoms, residues R″ independently of each other are H, Na, K, Li or NH.sub.4; and n is an integer from 0 to 4; and where the at least two different amino organophosphonic acid derivatives differ in the value of n. Further disclosed herein is a concentrate to produce such compositions, a pickling method for pickling metallic substrates making use of the compositions, a coating method for coating metallic substrates including the pickling method and a method of using the compositions for pickling metallic substrates.

An inhibited hydrofluoric acid aqueous composition, said composition comprising: hydrofluoric acid in solution; and a weak base selected from the group consisting of: lysine, arginine, histidine, glutamine, asparagine, tryptophan, and tyrosine; wherein said weak base and hydrofluoric acid are present in a molar ratio of at least 1:1. Also disclosed is a mud acid using this inhibited acid composition.

A neutralizer, destainer/descaling, and passivating composition and methods of using the same on metal surfaces are disclosed. The compositions are particularly well suited for the treatment of health care surfaces and other hard surfaces in need of treatment. In particular, the neutralizer, destainer/descaling, and passivating composition is an acid-based composition for use in instrument reprocessing.

There is provided a cleaning method and a cleaning apparatus capable of removing dirt on electrical contacts, the dirt being unable to be removed with deionized water, without adversely affecting a plating solution and a substrate holder which is a member for holding a substrate. A cleaning method according to the present disclosure is a cleaning method for a substrate holder having electrical contacts for supplying electric power to a substrate by contacting the substrate to plate the substrate, the method including a cleaning step of cleaning the electrical contacts attached to the substrate holder with a citric acid aqueous solution.

An aqueous synthetic acid composition is disclosed for use in oil industry activities, the composition comprising: lysine and hydrogen chloride in a molar ratio ranging from 1 to 1:12.5, preferably from more than 1:5 to 1:8.5. The composition can also further comprise a metal iodide or iodate; an alcohol or derivative thereof. The composition demonstrates advantageous properties over known synthetic acids at temperatures above 90° C. The composition is useful in various oil and gas industry operations. Preferred embodiments of the composition provide substantial advantages in matrix acidizing by increasing the effectiveness of wormholing as compared to conventional mineral acids such as HCl.

An inhibited hydrofluoric acid aqueous composition, said composition comprising: hydrofluoric acid in solution; and a weak base selected from the group consisting of: lysine, arginine, histidine, glutamine, asparagine, tryptophan, and tyrosine; wherein said weak base and hydrofluoric acid are present in a molar ratio of at least 1:1. Also disclosed is a mud acid using this inhibited acid composition.

The need for an acidic liquid hard surface cleaning composition which provides improved removal of grease residues, while still being effective at removing limes-scale, is met by formulating an acidic liquid hard surface cleaning composition with an alkyl pyrrolidone, and additional nonionic surfactant selected from the group consisting of: alkoxylated nonionic surfactant, alkyl polyglucoside, and mixtures thereof, while limiting the amount of anionic surfactant present.

A surface treatment agent capable of forming a hexavalent chromium-free chemical conversion coating that can provide an excellent corrosion-resistant coating on various metallic materials; a metallic material having a surface treatment coating obtained therefrom; and a method of producing the same. A free fluorine ion-containing surface treatment agent for surface-treating a metallic material, which is obtained by mixing at least one supply source (A) of trivalent chromium-containing ions A; a supply source (B) of ions B that are at least one selected from titanium-containing ions and zirconium-containing ions; a water-soluble or water-dispersible compound (C) containing an alkoxysilyl group, an aromatic ring, a hydroxy group directly bonded to the aromatic ring, and at least one of primary, secondary, tertiary and quaternary amino groups, wherein the alkoxysilyl group is bonded to the nitrogen atom of the amino group directly or via an alkylene group; and a fluorine-containing compound (D) providing fluorine-containing ions.

A composition for inhibiting corrosion and/or removing hydrocarbonaceous deposits in oil and gas applications is provided. The composition comprises an iron sulfide dissolver, an organic solvent, and a corrosion inhibitor.

A medical product and a method of surface treatment and/or manufacture of the medical product. The method includes the step of electrochemically etching the medical product. The medical product can include a metal or alloy and have one or more of the following features: a pitting corrosion potential of 100 mV to 1200 mV, a contact angle of 90° to 140°, and a passive layer having a thickness of 1 nm to 10 nm that coats at least sections of the surface of the medical product.