An object of the invention is to provide a heat-resistant hexavalent chromium removal agent, which is capable of remaining in a leather or leather article for a long period of time and stably detoxifying hexavalent chromium over the long term even when a leather or leather article contains hexavalent chromium, and a leather or leather article, in which the hexavalent chromium content is less than 3 ppm. The leather or leather article of the present invention contains at least: an organic compound (A) having a structure shown in chemical formula (1) and hydroxyphenyl but not aldehyde and carboxyl, which organic compound has a property to reduce hexavalent chromium to trivalent chromium; and trivalent chromium, and the hexavalent chromium content determined in accordance with ISO 17075: 2008-02 is less than 3 ppm.

Provided is a composition for manufacturing leather comprising: hydroxide and borax (Na.sub.2B.sub.4O.sub.7•10H.sub.2O).

Provided is a composition for manufacturing leather comprising: hydroxide and borax (Na.sub.2B.sub.4O.sub.7•10H.sub.2O).

Provided is a method of manufacturing leather, comprising: preparing fabric including soaking, fleshing, liming, reliming, band knifing, deliming, and bating of natural leather; shaving the prepared fabric to a uniform thickness; neutralizing the shaved fabric to a pH of 5 to 7; flame retardant processing of performing a flame retardant treatment on the neutralized fabric with a composition for manufacturing leather; and drying the flame retardant treated fabric.

A method is provided for producing sustainable leather using by-products from parts of all varieties and species of the plant genus Persea including among them both the American species and the Hass variety. A hide or leather may be produced by the method, and a method is provided for producing the natural tanning agents used in the method to produce sustainable leather and the natural tanning agents produced by the method.

A method is provided for producing sustainable leather using by-products from parts of all varieties and species of the plant genus Persea including among them both the American species and the Hass variety. A hide or leather may be produced by the method, and a method is provided for producing the natural tanning agents used in the method to produce sustainable leather and the natural tanning agents produced by the method.

The invention relates to a poly silsesquioxane-acrylic nanocomposite auxiliary for leather process and its preparation method. By mixing octavinyl silsesquioxane, organic solvent, ammonium persulfate, distilled water and surfactant in one system, and adding acrylic acid dropwise into the mixing system, cooling to adjust pH to obtain poly silsesquioxane-acrylic nanocomposite auxiliary for leather process. The auxiliary obtained in this invention is easily to penetrate into gap of the collagen fibers, and forms nano and micro-scale combination with the leather collagen, which can further improve the multi-point combination of the acrylic polymer with the collagen. Thus, the filling property of the leather that treated by the auxiliary is improved without affect the yield of leather, and the chromium content in the waste water is significantly reduced.

The invention relates to a poly silsesquioxane-acrylic nanocomposite auxiliary for leather process and its preparation method. By mixing octavinyl silsesquioxane, organic solvent, ammonium persulfate, distilled water and surfactant in one system, and adding acrylic acid dropwise into the mixing system, cooling to adjust pH to obtain poly silsesquioxane-acrylic nanocomposite auxiliary for leather process. The auxiliary obtained in this invention is easily to penetrate into gap of the collagen fibers, and forms nano and micro-scale combination with the leather collagen, which can further improve the multi-point combination of the acrylic polymer with the collagen. Thus, the filling property of the leather that treated by the auxiliary is improved without affect the yield of leather, and the chromium content in the waste water is significantly reduced.

A method is provided for producing sustainable leather using by-products from parts of all varieties and species of the plant genus Persea including among them both the American species and the Hass variety. A hide or leather may be produced by the method, and a method is provided for producing the natural tanning agents used in the method to produce sustainable leather and the natural tanning agents produced by the method.

A method is provided for producing sustainable leather using by-products from parts of all varieties and species of the plant genus Persea including among them both the American species and the Hass variety. A hide or leather may be produced by the method, and a method is provided for producing the natural tanning agents used in the method to produce sustainable leather and the natural tanning agents produced by the method.