Provided is a black coupling member for vehicles, comprising a trivalent chromium black chemical conversion film and a black coating film upon the trivalent chromium black chemical conversion film, on the surface of a zinc-plated metal substrate. The trivalent chromium black chemical conversion film is formed using a hexavalent chromium-free trivalent chromium black chemical conversion treatment solution having a Zn ion concentration of no more than 20 g/L. The lightness (L) of the trivalent chromium black chemical conversion film is no more than 33. The black coating film includes a black chemical conversion component, a modified organopolysiloxane, and a friction coefficient-adjustment component. The black chemical conversion component content is 2-25 wt % relative to 100 wt % of the black coating film. The lightness (L) is no more than 28.

Provided is a black coupling member for vehicles, comprising a trivalent chromium black chemical conversion film and a black coating film upon the trivalent chromium black chemical conversion film, on the surface of a zinc-plated metal substrate. The trivalent chromium black chemical conversion film is formed using a hexavalent chromium-free trivalent chromium black chemical conversion treatment solution having a Zn ion concentration of no more than 20 g/L. The lightness (L) of the trivalent chromium black chemical conversion film is no more than 33. The black coating film includes a black chemical conversion component, a modified organopolysiloxane, and a friction coefficient-adjustment component. The black chemical conversion component content is 2-25 wt % relative to 100 wt % of the black coating film. The lightness (L) is no more than 28.

Provided are a novel chemical conversion treatment agent which is capable of forming, on/over the surface of a metal material, a chemical conversion coating which is superior in corrosion resistance, a method for producing a chemical conversion coating on/over the surface of a metal material with the use of the chemical conversion treatment agent, a metal material having a coating, and a painted metal material. The problem mentioned above can be solved by the chemical conversion treatment agent for forming a coating on/over the surface of a metal material, which characterized by containing: an ion containging at least one metal selected from the group consisting of titanium, zirconium and hafnium; a fluorine ion; at least one selected from the group consisting of an alkanesulfonic acid, an alkanolsulfonic acid, and ions thereof; and an ion containing trivalent iron.

Methods and compositions for treating a substrate are provided. The composition contains a corrosion-inhibiting metal cation and a conjugated compound.

Low reflection articles, and related systems and methods are disclosed. The articles have a surface with primary pores and secondary pores. At least some of the secondary pores contain agent, such, for example, a light absorbing dye.

A method for applying an anti-corrosion coating to a substrate includes: applying an anti-corrosion composition; and applying a dye which exhibits fluorescence when exposed to ultraviolet radiation.

A method for applying an anti-corrosion coating to a substrate includes: applying an anti-corrosion composition; and applying a dye which exhibits fluorescence when exposed to ultraviolet radiation.

Low reflection articles, and related systems and methods are disclosed. The articles have a surface with primary pores and secondary pores. At least some of the secondary pores contain agent, such, for example, a light absorbing dye.

Low reflection articles, and related systems and methods are disclosed. The articles have a surface with primary pores and secondary pores. At least some of the secondary pores contain agent, such, for example, a light absorbing dye.

Low reflection articles, and related systems and methods are disclosed. The articles have a surface with primary pores and secondary pores. At least some of the secondary pores contain agent, such, for example, a light absorbing dye.