Leather or leather article and method for producing same, hexavalent chromium treatment agent, method for treating hexavalent chromium in crude leather or crude leather article

A leather or leather article, containing at least:

• an organic compound (A) having a structure shown in chemical formula (1) below and hydroxyphenyl, wherein said organic compound (A) does not have reactive functional groups of an aldehyde and carboxyl, the organic compound acting to reduce hexavalent chromium to trivalent chromium;
• an organic compound (B) having a structure shown in chemical formula (1) wherein said organic compound (B) does not have a hydroxyphenyl, aldehyde, and carboxyl, the compound (B) acting to reduce hexavalent chromium to trivalent chromium;
• and
• trivalent chromium, wherein the hexavalent chromium content is less than 3 ppm:
• (where R1, R2, R3, R4 and R5 are each independently a substituent composed of at least one selected from C, H and O, and R1 or R2 may be combined with R3, R4, or R5 to form a ring).

A hexavalent chromium treatment agent, containing at least:

• an organic compound (A) having a structure shown in chemical formula (1) and hydroxyphenyl, wherein said organic compound (A) does not have reactive functional groups of an aldehyde and carboxyl, the organic compound acting to reduce hexavalent chromium to trivalent chromium;
• and
• an organic compound (B) having a structure shown in chemical formula (1) wherein said organic compound (B) does not have a hydroxyphenyl, aldehyde, and carboxyl, the organic compound acting to reduce hexavalent chromium to trivalent chromium:
• (where R1, R2, R3, R4 and R5 are each independently a substituent composed of at least one selected from C, H and O, and R1 or R2 may be combined with R3, R4, or R5 to form a ring).

A hexavalent chromium treatment agent, containing at least:

• an organic compound (A) having a structure shown in chemical formula (1) and hydroxyphenyl, wherein said organic compound (A) does not have reactive functional groups of an aldehyde and carboxyl, the organic compound acting to reduce hexavalent chromium to trivalent chromium;
• and
• at least two solvents selected from the group consisting of water, C1-C3 alcohol, hexane, and heptane,
• wherein the hexavalent chromium treatment agent is capable of permeating a leather or leather article:
• (where R1, R2, R3, R4 and R5 are each independently a substituent composed of at least one selected from C, H and O, and R1 or R2 may be combined with R3, R4, or R5 to form a ring).