A chemical surface treatment method of a metal improves bonding of different materials in which first pores are formed in the surface of the metal and second pores are formed locally in the surfaces of the first pores by appropriately setting the number of repetitions of alkali treatment and acid treatment, the concentrations of treatment solutions, and treatment temperatures and times using the treatment solutions. The method includes performing the alkali treatment by immersing the metal in a base solution, so as to form first pores in a surface of the metal. The method further includes performing the acid treatment by immersing an alkali-treated result product in an acid solution, so as to form second pores locally in surfaces of the first pores.

Provided is a method for producing an electrode for an electrolytic capacitor, the method comprising: a hydration step in which an aluminum electrode is immersed in a hydration treatment solution having a temperature of 80 C. or higher; and a chemical conversion step in which the aluminum electrode is subjected to chemical conversion treatment up to a formation voltage of at least 400 V. The hydration treatment solution contains a hydration inhibitor. The thickness of a hydrated film formed in the hydration step satisfies the following condition, 0.6t2/t11, wherein t1 is the average thickness of the hydrated film formed in a depth range of up to 100 m from the surface of the aluminum electrode, and t2 is the average thickness s of the hydrated film formed in a deep portion at least 100 m from the surface of the aluminum electrode.

The present invention addresses the problem of providing, a metal surface treatment agent capable of exhibiting excellent corrosion resistance and excellent coating adhesion in painted metal materials; and a metal surface treatment method using the metal surface treatment agent. The problem is solved by a pretreatment agent that is used in a pretreatment of a chemical conversion treatment performed for forming a chemical conversion coating on/over a surface of a metal material, the pretreatment agent containing: a metal alkoxide (A) containing at least one metal element selected from zirconium, titanium, vanadium, and aluminum; and at least one sulfonic acid (B) selected from methanesulfonic acid, ethanesulfonic acid, hydroxymethanesulfonic acid, and hydroxyethanesulfonic acid. The problem is also solved by a chemical conversion treatment agent that contains a zirconium alkoxide (a) and a zirconium-containing ion supply source (b), and has a pH of 1.5 to 6.5.

The invention relates to polyfunctional polymers suitable in particular for the treatment of metal surfaces (metal finishing) and comprising: monomer units u1 bearing phosphonic acid functions; monomer units u2 bearing amine functions; and optionally monomer units u3 bearing alcohol units OH.

A method produces a coating treatment solution to be used for forming a ferrite film having a spinel type crystal structure MFe.sub.2O.sub.4 on a surface of a soft magnetic material. The coating treatment solution contains a solution having a metal element and Fe. The metal element becomes divalent cations in the solution. The method prepares a first solution containing the metal element M and Fe, prepares a second solution by adding an alkaline solution to the first solution in a non-oxidizing atmosphere. The method produces the coating treatment solution by using the second solution.

A method produces a coating treatment solution to be used for forming a ferrite film having a spinel type crystal structure MFe.sub.2O.sub.4 on a surface of a soft magnetic material. The coating treatment solution contains a solution having a metal element and Fe. The metal element becomes divalent cations in the solution. The method prepares a first solution containing the metal element M and Fe, prepares a second solution by adding an alkaline solution to the first solution in a non-oxidizing atmosphere. The method produces the coating treatment solution by using the second solution.

A novel method of blackening surgical needles is disclosed. Surgical needles having outer surfaces are first placed into a first pretreatment bath having a novel composition. The needles are then placed into a second blackening bath having a novel composition for a sufficient period of time to effectively blacken the surfaces of the needles. The novel methods for blackening the surfaces of a stainless steel alloy surgical needle provide a chromium (VI)-free alternative to current needle manufacturing processes. Another unique feature of this novel method is its short processing time. The blackening processes of the present invention can be utilized for in-line treatment processes which can be easily incorporated into high speed needle manufacturing processes, such as strip mounted processes. In addition, the processes of the present invention are readily adaptable to batch processes. Also disclosed are novel systems for blackening surgical needles and novel blackening baths for surgical needles.

A novel method of blackening surgical needles is disclosed. Surgical needles having outer surfaces are first placed into a first pretreatment bath having a novel composition. The needles are then placed into a second blackening bath having a novel composition for a sufficient period of time to effectively blacken the surfaces of the needles. The novel methods for blackening the surfaces of a stainless steel alloy surgical needle provide a chromium (VI)-free alternative to current needle manufacturing processes. Another unique feature of this novel method is its short processing time. The blackening processes of the present invention can be utilized for in-line treatment processes which can be easily incorporated into high speed needle manufacturing processes, such as strip mounted processes. In addition, the processes of the present invention are readily adaptable to batch processes. Also disclosed are novel systems for blackening surgical needles and novel blackening baths for surgical needles.

This disclosure relates to method phosphating an iron surface susceptible to corrosion, the method comprising contacting an iron surface with an aqueous mixture of an acidic phosphate component, a basic component, and at least one silicate; and forming a passivation zone chemically bound to the iron surface of one or more iron ions corresponding to the iron surface, the acidic phosphate component, the basic component, and at least one corrosion inhibitor precursor.

This disclosure relates to method phosphating an iron surface susceptible to corrosion, the method comprising contacting an iron surface with an aqueous mixture of an acidic phosphate component, a basic component, and at least one silicate; and forming a passivation zone chemically bound to the iron surface of one or more iron ions corresponding to the iron surface, the acidic phosphate component, the basic component, and at least one corrosion inhibitor precursor.