The invention concerns the use of a hemp oil derivative in at least one step of the leather working process in the tanning industry, wherein said hemp oil derivative is selected from the group consisting of sulphated hemp oil, sulphited hemp oil, phosphated hemp oil and mixtures thereof. The invention also concerns a composition comprising: a hemp oil derivative selected from the group consisting of sulphated hemp oil, sulphited hemp oil, phosphated hemp oil and mixtures thereof, and—a phosphated (C.sub.8-C.sub.24) fatty alcohol having from 1 to 2 hydroxyl groups.

The invention concerns the use of a hemp oil derivative in at least one step of the leather working process in the tanning industry, wherein said hemp oil derivative is selected from the group consisting of sulphated hemp oil, sulphited hemp oil, phosphated hemp oil and mixtures thereof. The invention also concerns a composition comprising: a hemp oil derivative selected from the group consisting of sulphated hemp oil, sulphited hemp oil, phosphated hemp oil and mixtures thereof, and—a phosphated (C.sub.8-C.sub.24) fatty alcohol having from 1 to 2 hydroxyl groups.

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.

A process is provided for obtaining a tannin extract isolated from grapes using grape seeds. The process comprises: preparing the grape seeds as the source of tannins; preparing an aqueous solution of a polyphenol-solubilising agent selected from urea, a compound containing the SO.sub.3 group and sodium hydroxide at concentration ranging between 1% and 15% by weight; performing a single extraction in an autoclave reactor; separation and direct concentration in order to produce the isolated extract. The invention also relates to the tannin extract obtained. The new tannin extract isolated from grape seeds comprises a mixture of tannins and non-tannins, the composition whereof provides the extract with improved antioxidant and light fastness properties. The tannin extract isolated from grape seeds further comprises a colouring agent.

A process for obtaining a tannin extract isolated from whole grape seeds is provided. The process is performed in as a one-pot reaction and in a single extraction step, wherein the seeds are processed without grinding or milling. Also provided is a tannin extract with improved antioxidant and light fastness properties obtained from whole grape seeds that includes a mixture of tannins and non-tannins, in which the content of tannins or polyphenols is higher than 50%. Ise, the tannin extract isolated from whole grape seeds can include a coloring agent.

A process for obtaining a tannin extract isolated from whole grape seeds is provided. The process is performed in as a one-pot reaction and in a single extraction step, wherein the seeds are processed without grinding or milling. Also provided is a tannin extract with improved antioxidant and light fastness properties obtained from whole grape seeds that includes a mixture of tannins and non-tannins, in which the content of tannins or polyphenols is higher than 50%. Ise, the tannin extract isolated from whole grape seeds can include a coloring agent.

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.

Disclosed is a preparation method of a plant biomass-based active tanning agent. Under a low-temperature reaction condition, cyanuric chloride and a plant biomass compound are used to synthesize an environment-friendly plant biomass-based active tanning agent through a nucleophilic substitution reaction. The active tanning agent obtained in the present disclosure appears as a white or light brown emulsion at room temperature, and has substantial active groups such as hydroxyl groups, carboxyl groups and ester groups introduced into its structure, thus endowing leathers with desirable hydrothermal stability and physical properties and having a desirable synergistic effect with metal tanning agents. Meanwhile, health and environment risks caused by hexavalent chromium and free formaldehyde in leathers are avoided.