The present disclosure provides a collagen-infused composite material comprising an optionally functionalized armature including a base substrate and one or more and non-woven substrates. The non-woven substrate(s) can be directly coupled to a topmost surface and/or bottommost surface of the base substrate. The material properties and/or collagen infusion capacities of the base substrate and the non-woven substrate(s) can be tailored to create a collagen-infused composite material with characteristics that mimic those of a natural leather. In some embodiments, the base substrate can be spacer fabric. In some embodiments, the armature can be functionalized to facilitate the crosslinking the collagen to the armature during one or more tanning processes.

An apparatus includes a process chamber, a controllable compressor for pressurizing a fluid, a pressure reducing member, an inlet for a processing agent and a controller. The process chamber is a pressure chamber. The controllable compressor pressurizes a fluid and introduces the pressurized fluid into the process chamber from a source. Further the controllable compressor controls a predefined pressure in the process chamber to reach a supercritical state of the fluid. An inlet for a processing agent facilitates introduction of the processing agent into the process chamber prior to, during, or subsequent to pressurization of the fluid. The pressure reducing member reduces the pressure of the fluid at least to reach a gaseous state subsequent to processing the leather object such that the time for reduction of pressure exceeds a predefined reduction period or the reduction of pressure does not exceed a predefined leather pressure reduction gradient.

A method for dyeing and/or retanning of leather objects includes providing a leather object. The leather object has been processed by at least a tanning process. The leather object is introduced into a process chamber. The leather object is subjected in the process chamber to a pressurized fluid. The pressure of the pressurized fluid is controlled to reach a supercritical state. The leather object is subjected to a dyeing agent and/or a retanning agent, which dyeing or retanning agent is dissolved and/or transported in the pressurized fluid for at least a predefined period of time while the pressurized fluid is in the supercritical state. The pressure is reduced in the process chamber. The leather object is removed from the process chamber. The pressure reduction is controlled over time.

A method of dyeing collagen fiber includes providing collagen fiber and dyeing the collagen fiber.

A process for the simultaneous tanning and dyeing of collagen containing fibrous material, wherein the said material is treated with a liquor containing at least one reactive dyestuff selected from the group of formula (1) and (2)

##STR00001## wherein A.sub.1, A.sub.2 and A.sub.3 are each independently of the others the radical of a monoazo, polyazo, metal-complexed azo, anthraquinone, phthalocyanine, formazan or dioxazine chromophore having at least one sulfo group, B is an organic bridge member, Q.sub.1, Q.sub.2, Q.sub.3 and Q.sub.4 are each independently of the others hydrogen or unsubstituted or substituted C.sub.1-C.sub.4alkyl, G.sub.1 and G.sub.2 are halogen, 3-carboxypyridin-1-yl or 3-carbamoylpyridin-1-yl, (Z.sub.1).sub.2-3 is 2 to 3 identical or different fiber reactive radicals, Z.sub.2 and Z.sub.3 are each independently of the other identical or different fiber reactive radicals, and b is the number 0 or 1, by combining two steps of leather production, tanning and dyeing, into a single step, thus, preserving resources and reducing the environmental impact.

The present invention relates to the use of reactive colourless and metal-free protein cross-linking agents for the cross-linking (tanning) of protein-containing substrates, said agents are environmentally friendly and give an improved fixation yield, a long-term cross-linking (tanning) stability and good washing off properties. The present invention further relates to processes for the cross-linking (tanning) of protein-containing substrates thereby creating an environmentally friendly process which minimizes the use of chemicals and further improves the quality and efficiency of the tanning and dyeing process.

##STR00001##

A method for dyeing and/or retanning of leather objects includes providing a leather object. The leather object has been processed by at least a tanning process. The leather object is introduced into a process chamber. The leather object is subjected in the process chamber to a pressurized fluid. The pressure of the pressurized fluid is controlled to reach a supercritical state. The leather object is subjected to a dyeing agent and/or a retanning agent, which dyeing or retanning agent is dissolved and/or transported in the pressurized fluid for at least a predefined period of time while the pressurized fluid is in the supercritical state. The pressure is reduced in the process chamber. The leather object is removed from the process chamber. The pressure reduction is controlled over time.

A method for dyeing and/or retanning of leather objects includes providing a leather object. The leather object has been processed by at least a tanning process. The leather object is introduced into a process chamber. The leather object is subjected in the process chamber to a pressurized fluid. The pressure of the pressurized fluid is controlled to reach a supercritical state. The leather object is subjected to a dyeing agent and/or a retanning agent, which dyeing or retanning agent is dissolved and/or transported in the pressurized fluid for at least a predefined period of time while the pressurized fluid is in the supercritical state. The pressure is reduced in the process chamber. The leather object is removed from the process chamber. The pressure reduction is controlled over time.

The invention provides a process for tanning a substrate using at least one ionic liquid. The at least one ionic liquid can be used in at least one of the following tanning steps: tanning, re-tanning, preservation, liming, pickling, impregnation, lubrication, dyeing, fatliquoring or finishing.

A process for the simultaneous tanning and dyeing of collagen containing fibrous material, wherein the said material is treated with a liquor containing at least one reactive dyestuff selected from the group of formula (1) and (2) ##STR00001## wherein A.sub.1, A.sub.2 and A.sub.3 are each independently of the others the radical of a monoazo, polyazo, metal-complexed azo, anthraquinone, phthalocyanine, formazan or dioxazine chromophore having at least one sulfo group, B is an organic bridge member, Q.sub.1, Q.sub.2, Q.sub.3 and Q.sub.4 are each independently of the others hydrogen or unsubstituted or substituted C.sub.1-C.sub.4alkyl, G.sub.1 and G.sub.2 are halogen, 3-carboxypyridin-1-yl or 3-carbamoylpyridin-1-yl, (Z.sub.1).sub.2-3 is 2 to 3 identical or different fiber reactive radicals, Z.sub.2 and Z.sub.3 are each independently of the other identical or different fiber reactive radicals, and b is the number 0 or 1, by combining two steps of leather production, tanning and dyeing, into a single step, thus, preserving resources and reducing the environmental impact.