The present invention is concerned with methods of preparing dyestuffs from a liquid residue recovered from a liquid waste stream of a botanical biomass; dyestuffs made according to said methods; methods for dyeing and the use of the dyestuffs in colouring textiles, as well as textiles dyed with the dyestuffs.

BACKGROUND OF THE INVENTION

The majority of the output of the dyestuff industry today consists of synthetic dyes. Unfortunately, however, these materials contribute significantly to global water pollution, and the waste products attendant with the manufacture of many of them, as well as their degradation products, are associated with risks related to health, reproductive toxicity and allergy. Natural dyestuffs have become of greater interest recently for sustainability reasons. They were the original dyestuffs, but were largely supplanted in the 19 ^th century by synthetic dyestuffs, which could be made on a large scale.

At the same time, natural resources are becoming scarcer, and given the high demand for botanical resources generated by many industries including the food, flavour, fragrance and cosmetic industries, for the dyestuff manufacturers that would like to produce natural dyestuffs, the required raw materials remain difficult to obtain, and then only at very high cost, making the production of natural dyestuffs prohibitively expensive. Still further, although the food, flavour, fragrance and cosmetic industries consume significant quantities of botanical ingredients to create their products, they do not valorize all the waste streams that they produce.

Methods of extracting useful products from biomass are well known in industry. Typical examples of such useful products include flavours, fragrances, cosmetic ingredients, medicinal ingredients, nutritional or well-being ingredients. The method often used is distillation, in which the biomass is exposed to a suitable solvent and then distilled, the desirable product being found in the distillate. There then follows the problem of the disposal of what remains, which is made up of a solid residue and a liquid residue waste stream. The liquid waste stream is generally disposed of in an environmentally and economically unsatisfactory way, typically by pouring it into the sewage system. Thought has never been given as to whether such liquid waste streams or liquid residues could provide further useful products.

Methods of extracting botanical biomass to yield different fractions, which can be utilized and therefore valorized in different industries are known in the art. For example, US9, 215,885 describes a process of twice extracting fruit matter in a series of sequential steps to yield two fractions with different utility. A fruit juice is useful for its gustatory properties and can be valorized as such, whereas a pro-anthocyanidine extract can be valorized for its health & wellbeing benefits.

Through these various prior art processes, botanical materials are processed in sequential extraction steps to produce a plurality of valuable products having different utilities. However, such sequential processes involve once-extracted biomass residues being dehydrated to remove large amounts of moisture, and transported to other actors in the supply chain to carry out subsequent extraction steps. These supply chain activities are not only energy intensive and causing a large amount of greenhouse gas emissions, mainly emissions of CO2, they also create a significant toxicological hazard attendant to micro-organism proliferation in moist waste material being stored and transported over prolonged periods of time.

The use of certain plant types, cultivated specifically or partially for the colouring matters therein is well known. Some specific examples may be found in, for example, Adeel et al. in Journal of Natural Fibers (2022), 19 (13), 6089-6103, and Ekrami et al in World Applied Sciences Journal (2011), 13 (2), 295-299, which both explore rose petals as a source of natural colourant for wool dyeing, while Patil et al. in International Journal For Innovative Research In Multidisciplinary Field (2016), 2 (8), 135-137, explore it for cotton dyeing.

However, such production is carried out today by artisanal or academic actors who find problems in scalability because of low extraction yields and because they compete with the fragrance and food industries, at least, for raw materials.

The extraction of potential dyestuffs from waste products is also known. One possibility of some of these biomass-derived waste streams is the extraction of natural dyestuffs. While this is not universal among all biomasses, it is a possibility among a substantial number. For example, Bechtold et al in J Sci Food Agric 86:233-242 (2006) describe a process of extracting dyes from food and beverage industry wastes. The already-exhausted waste materials from mechanical extraction of solid plant parts are further processed in a separate and sequential step whereupon the dyestuffs are recovered in a laboured and energy intensive solvent extraction or distillation step.

US 9,340,675 describes a process of extracting natural dyes from a vegetal biomass that is the once-extracted residue of agricultural crops. The process requires collection and transportation of the waste biomass residue from an adjacent industrial activity before extracting it for at least 2 hours at a temperature of 120° to 350°C, which is time-consuming, energy inefficient and polluting.

The prior art also describes processes of extracting dyestuffs from rose and lavender waste stream pulp in solvents at temperatures ranging from 100° to 300°C. More particularly, Karaboyaci et al in The Journal of The Textile Institute, 105 (11), 1160-1166 describes a process of extracting rose petal pulp in boiling solvent for a period of 30 to 120 minutes. While the non-polar solvent extraction of essential oil from the rose flowers was done in industrial scale, the extraction of the colour was not. Although the waste is not dried in this process, the once-extracted pulp is nevertheless subjected to an energy inefficient and polluting additional extraction step. Furthermore, the process does not involve the recovery of the liquid residue of the liquid waste stream from the still. Finally, the method is hardly scalable as microbiological contamination of the wet waste (before the dyestuff extraction) happens within hours or days of storage, which makes its handling, and supply chain issues more generally difficult and even dangerous as toxic hydrogen sulphide can be generated and concentrates in enclosed and low oxygen environments.

A further prior art document, CN 104906007, explores the solid waste stream of the distillation process of a rose biomass from which the liquid residue of the still is filtered off exploiting the solid rose biomass for the generation of particular rose pigments for cosmetic applications. The liquid residue however is not used for extracting the rose pigment. And, the extraction of the rose dye rich fraction requires a 3-hour additional acid extraction step of the already exhausted rose biomass and two sequential complex separation steps. So, the overall process is energy intensive, complex, hardly scalable, comes at high cost and is therefore reserved to the isolation of high value compounds. Certainly, the number of steps in the process are not reduced but increased. It does not describe that the dyestuff can be used directly and without further chemical treatment. Thus, CN 104906007 can also not provide a solution to the problem of providing an inexpensive approach to natural dyestuffs without additional depletion of natural resources and energy.

In summary, the prior art does recognize the value in methods for producing natural dyestuffs from waste streams that can provide alternatives, or complements, to synthetic dyestuffs while avoiding depletion of natural resources, and maintaining botanical diversity. However, all of these processes posited in the prior art primarily involve the solid waste stream of the botanical biomass and by that involve the step of carrying out an energy-intensive and/or a polluting additional extraction and/or separation step on a once-extracted vegetal biomass. None of the prior art processes puts the skilled person in possession of a scalable industrial process of producing natural dyestuffs for a combination of reasons. These reasons include the complexity of the supply chain needed to gather harvested material in a timely fashion; the requirement to process the already exhausted waste biomass quickly, including by an energy intensive drying step, to avoid microbiological contamination and the attendant toxicological and safety risks; the complexity and portability of the equipment needed to process the waste quickly; the energy required to extract and produce natural dyestuffs from the biomass; and the cost, both in financial terms and also in terms of carbon dioxide emissions, not least added upon by transportation and logistics.

None of the prior art described above is concerned with the production of dyestuffs from an unrecognized waste stream of a botanical biomass distillation, and none tries to reduce the number of steps used in such processes in order to optimize valorisation of all ingredients of a botanical biomass. If the cited prior art documents tend to waste streams from such a process all documents focus on using the solid waste streams of the botanical biomass, none turn their focus on the liquid residue waste streams of the distillation still.

The prior art is blind about the direct use of the in-situ generated liquid waste streams of distillation processes of botanical biomasses for dyestuffs without further chemical treatment, such as pH adjusted extraction treatment. Today, the liquid residue waste stream generated during a distillation process is generally not collected but discarded directly into the sewage system.

There remains a need to provide a process of preparing natural dyestuffs from botanical biomass distillation waste streams in an energy-efficient and environmentally-friendly manner that is not encumbered by any of the problems associated with the prior art.

SUMMARY OF THE INVENTION

The object of the present invention is to address the deficiencies in the prior art and provide a sustainable, scalable and low-cost process to produce natural dyestuffs that are of use in the textile dyeing industry and which are superior in terms of economical sustainability, and accessible in industrial scale.

Accordingly, the invention provides in a first aspect a process of preparing a dyestuff comprising the steps of:

(i) providing a botanical biomass containing at least one volatile ingredient, including an oil, selected from a flavour, a fragrance, a cosmetic, a medicinal or a nutritional ingredient; and at least one natural dyestuff; (ii) heating the biomass in the presence of water and/or alcohol to separate said volatile ingredient, including an oil, and not including the natural dyestuff; from the botanical biomass by distillation, thus providing said at least one volatile ingredient as liquid distillate, and providing a solid residue and a liquid residue containing the dyestuff and

(iii) recovering the natural dyestuff in an aqueous and/or alcoholic solution from said liquid residue.

The invention provides in a second aspect an aqueous and/or alcoholic solution comprising a dyestuff obtained by the process according to the invention described herein.

The invention provides in a third aspect an aqueous and/or alcoholic solution comprising a dyestuff obtained by the process according to the invention described herein, characterized in that the dyestuff is recovered from the liquid residue of the still of said distillation process of said botanical biomass.

The invention provides in a fourth aspect a natural dyestuff produced by the process of the invention described herein.

The invention provides in a fifth aspect the use of an aqueous and/or alcoholic solution as defined in the invention herein for colouring a textile, a yarn and/or a fabric.

The invention provides, in a sixth aspect a textile, yarn and/or fabric coloured with the aqueous and/or alcoholic solution comprising the dyestuff.

The invention provides, in a seventh aspect, an apparatus for carrying out the process of preparing the distillate phase including the oil phase and the dyestuff.

The details, examples and preferences provided in relation to any one or more of the stated aspects of the present invention will be further described herein and apply equally to all aspects of the present invention. Any combination of embodiments, examples and preferences described herein below in all possible variations thereof are encompassed by the present invention unless otherwise indicated herein, or otherwise clearly contradicted by context. DESCRIPTION OF THE FIGURES

Figure 1. Wool fabric sample before dyeing according to example 2b

Figure 2. Wool fabric sample after dyeing according to example 2b with alum salt

Figure 3. Wool fabric sample after dyeing according to example 2b with ferrous sulphate salt

Figure 4. Wool yarn sample before dyeing according to example 4c

Figure 5. Wool yarn samples after dyeing with lavandin upcycled natural dye according to example 4c

Wool yarn samples in the figure from left to right, from top to bottom:

- dyed wool with no mordant and 0.08kg of lavandin upcycled natural dye,

- dyed wool with no mordant and 0.8kg of lavandin upcycled natural dye,

- dyed wool with 0.8kg of lavandin upcycled natural dye and using ferrous sulphate salt as a mordant (ferrous sulphate salt concentration 5g/l in dye bath),

- dyed wool with 0.8kg of lavandin upcycled natural dye and using alum salt as a mordant (alum salt concentration 5g/l in dye bath.

Figure 6. Wool yarn samples after dyeing with 0.8kg of violet upcycled natural dye according to example 4c

Wool yarn samples in the figure from left to right:

- dyed wool with no mordant,

- dyed wool with potassium alum as a mordant (alum salt concentration 5g/l in dye bath),

- dyed wool with tannic acid used as a mordant (tannic acid concentration 5g/l in dye bath).

Figure 7. Wool yarn samples after dyeing with sandalwood upcycled natural dye according to example 4c

Wool yarn samples in the figure from left to right, from top to bottom:

- dyed wool with no mordant and 0.8kg of sandalwood upcycled natural dye,

- dyed wool with 0.8kg of sandalwood upcycled natural dye and using ferrous sulphate salt as a mordant (ferrous sulphate salt concentration 5g/l in dye bath), - dyed wool with 0.8kg of sandalwood upcycled natural dye and using alum salt as a mordant (alum salt concentration 5g/l in dye bath),

- dyed wool with no mordant and 0.08kg of sandalwood upcycled natural dye.

Figure 8. Wool yarn samples after dyeing with 0.8kg of pepper mint upcycled natural dye according to example 4c

Wool yarn samples in the figure from left to right and from top to bottom:

- dyed wool with no mordant,

- dyed wool with potassium alum as a mordant (alum salt concentration 5g/l in dye bath),

- dyed wool with ferrous sulphate salt used as a mordant (ferrous sulphate salt concentration 1 g/L in dye bath),

- dyed wool with ferrous sulphate salt used as a mordant (ferrous sulphate salt concentration 5g/L in dye bath).

DETAILED DESCRIPTION OF THE INVENTION

The prior art as it relates to processes of obtaining dyestuffs from once-extracted vegetal biomass residues teaches that in order to extract a dyestuff, the biomass must be subject to pre-treatments, for example treatment with an acid, or boiling at high temperatures for long periods of time. The once-extracted biomass residues employed can either be in a dried state, the provision of which dried mass is an energy-intensive process and disadvantageous as such, or in the form of a pulp, which is also problematic because not only does storing and transporting wet biomass create a risk of microbial contamination, and subsequently safety issues, but the transportation of wet bulky residue requires a large storage infrastructure, or drying the wet biomass before transportation, is very energy inefficient and is environmentally unfriendly, and costly as such.

The present invention is based on the surprising discovery that the extraction of fresh botanical biomass by distillation for the primary purpose of recovering and collecting distillate fractions such as fractions of volatile ingredients, or in particular oil fractions, useful in food, flavouring, fragrance, cosmetic, medicinal, nutritional or well-being applications results in the concomitant creation of a highly coloured aqueous waste. This highly coloured liquid waste often referred to as still bottoms, resulting, for example from backflow from the still bottoms with a solvent, and/or from maceration, contains hydrophilic dyestuff molecules in sufficiently high concentrations as to be a suitable dyestuff for use in colouring textiles, yarns and/or fabrics, and that is the case even though water is not the optimal solvent for the dyestuff, this is just because of repeated and prolonged exposure to the dyestuff, preferably at high temperatures. The simultaneity of valorizing a botanical biomass by producing multiple products with different utility using a single-step or one-pot process, i.e. the simultaneous valorisation of the biomass by producing a valuable volatile ingredient received in the distillate and producing a dyestuff from the liquid residue of the liquid waste stream from the still all in one distillation process of such a biomass was not apprehended by the prior art.

By “single-step” or “one-pot” process is meant that the two desirable products, the volatile and/or lipophilic ingredients including oils and the natural dyestuff, are produced in a single- step procedure. It does not mean that further extraction and purification steps will not be needed in respect of each of the desirable products, but that the process will provide endproducts, from which the desired ingredients may be extracted.

It is, of course, recognised in the art that, while many imaginable liquid waste streams produced in this process are valuable sources of natural dyestuffs, there are others whose colouration is not suitable for recovery as a dyestuff. Those that are suitable are well known to the art, or their suitability can easily be determined in every case by routine, non-inventive test procedures.

Given that both a first valuable product in the liquid distillate such as a fragrance, flavour, cosmetic, medicine or other functional ingredient such as a well-being or nutritional ingredient, as well as a second valuable product - a natural dyestuff contained in the liquid residue of the still - can be simultaneously isolated from a botanical biomass in accordance with the present invention, the botanical biomass can be valorized as a source of not one, but multiple products with different properties and utilities, without any additional apparatus or other investment needed to isolate the dyestuff. Furthermore, the complex logistics and cost of processing, transporting and storing once-extracted botanical biomass, i.e. the solid residue of the botanical biomass, is avoided. Still further, the isolation and recovery of the dyestuff can be CO2 neutral as no additional energy needs to be expended over that used to isolate the first product. And finally, because there is no lengthy transportation or storage of solid waste biomass before extraction of the dyestuff, the whole process is less susceptible to the risks associated with microbial contamination and associated safety issues such as generation of toxic fermentation gasses like carbon monoxide or dihydrogen sulphide.

As used herein, the term botanical biomass is intended to refer to plant material, algae or fungi in a form in which it is harvested or otherwise obtained from forestry, agricultural, aquaculture or horticultural activities in unexploited form, and more specifically, in a form not extracted to remove valuable material from it. The biomass can be sourced, in particular, from alimentary crops, such as fruits and vegetables, herbs, trees, including but not limited to flower trees, deciduous trees, bushes and pine trees, or the resin or gums obtained therefrom. The term includes whole plants, or parts thereof, including roots, leaves, flowers, twigs, aerial parts, seeds, pulp, peels, rind, resins, gum, petals, draff, wood, root, beans, stems, fruits and the like. The term also includes plants or parts thereof that can be operated upon, for example by slicing, chopping, pelletizing, cutting, drying, grinding or milling, macerating or fermenting before being used in a process according to the present invention. The term is not intended to include waste residues, or any biomass already extracted or exhausted, by a hydrophilic solvent or an aqueous solvent, such as water or an alcohol, or mixtures thereof, in another industrial process. However, the term may include waste residues or a biomass already extracted or exhausted by a hydrophobic solvent, such as hexane, heptane, ethyl acetate, cyclohexane, toluene, dichloromethane, methyl tetrahydrofuran or a mixture thereof. In the case of an already extracted biomass extracted by such a hydrophobic solvent the waste biomass contains residues of the hydrophobic solvent which need to be removed before the waste biomass can be composted. Thus, in order to remove the hydrophobic solvent from the biomass it has to be subjected to an additional distillation step, preferably a steam distillation. This additional, but required distillation allows then to remove the dyestuffs from the already extracted biomass, which remained in the biomass despite the previous extraction step as the hydrophobic solvent does not, or not sufficiently, dissolve the dyestuffs.

In accordance with certain embodiments, the process of the present invention can be carried out by a process comprising the steps of distillation, in particular with water as the solvent which is called hydro-distillation, with alcohol as solvent which is then called alcoholic distillation, with a mixture of water and alcohol as solvent which is then called hydro-alcoholic distillation, or if the solvent is heated to steam, which is called steam distillation, in particular water steam distillation, alcoholic or hydro-alcoholic steam distillation. Also possible are respective distillation or steam distillation processes using any freely water soluble solvent.

In particular embodiments of the invention, the process of preparing the dyestuff comprises the steps of: i. providing a botanical biomass containing an oil useful as a flavour, fragrance, cosmetic, medicinal or well-being ingredient; ii. heating the biomass in the presence of water to separate the oil-containing phase from an aqueous phase containing the dyestuff; and iii. recovering the dyestuff in an aqueous solution. In particular embodiments of the invention, the process of preparing the dyestuff comprises the steps of: i. providing a botanical biomass containing at least one volatile ingredient, including an oil, selected from a flavour, a fragrance, a cosmetic, a medicinal or a nutritional ingredient; and a natural dyestuff; ii. heating the biomass in the presence of water to separate said volatile ingredient, including an oil, and not including the natural dyestuff; from the botanical biomass by distillation, thus providing said at least one volatile ingredient as liquid distillate, and providing a solid residue and a liquid residue, and iii. recovering the natural dyestuff in an aqueous solution from said liquid residue.

In particular embodiments of the invention, the process of preparing the dyestuff comprises the steps of: i. providing a botanical biomass containing at least one volatile ingredient, including an oil, selected from a flavour, a fragrance, a cosmetic, a medicinal or a nutritional ingredient; and a natural dyestuff; ii. heating the biomass in the presence of water and/or alcohol to separate said volatile ingredient, including an oil, and not including the natural dyestuff; from the botanical biomass by distillation, thus providing said at least one volatile ingredient as liquid distillate, and providing a solid residue and a liquid residue, and iii. recovering the natural dyestuff in an aqueous and/or alcoholic solution from said liquid residue.

In accordance with another embodiment, the process of preparing the dyestuff comprises the steps of: i. providing a botanical biomass containing an oil useful as a flavour, fragrance, cosmetic or medicinal ingredient; ii. subjecting the biomass to a process of hydro-distillation to separate said oil-containing phase from an aqueous phase containing the dyestuff; and iii. recovering the dyestuff in an aqueous solution.

In accordance with another embodiment, the process of preparing the dyestuff comprises the steps of: i. providing a botanical biomass containing at least one volatile ingredient including an oil selected from a flavour, a fragrance, a cosmetic, a medicinal or a nutritional ingredient; and at least one natural dyestuff; ii. subjecting the biomass to a process of hydro-distillation to separate said at least one volatile ingredient, including an oil, and not including the natural dyestuff, from the liquid residue containing the dyestuff; and iii. recovering the natural dyestuff in an aqueous solution from said liquid residue.

In accordance with another embodiment, the process of preparing the dyestuff comprises the steps of: i. providing a botanical biomass containing at least one volatile ingredient including an oil selected from a flavour, a fragrance, a cosmetic, a medicinal or a nutritional ingredient; and at least one natural dyestuff; ii. subjecting the biomass to a process of hydro-distillation, alcoholic or hydro-alcoholic distillation to separate said at least one volatile ingredient, including an oil, and not including the natural dyestuff, from the liquid residue containing the dyestuff; and iii. recovering the natural dyestuff in an aqueous and/or alcoholic solution from said liquid residue.

The distilled useful volatile ingredient, essentially also qualifying as lipophilic ingredient, may be a natural or essential oil, and it is to this possibility that reference will be made in the following description. However, there are other useful ingredients that are not oils that may also be distilled over, and the use of the word “oil” is considered to encompass these other possibilities.

The term “distilling” as used in the present invention shall mean that the substance or ingredient distils over to the receptacle receiving the distillate to become the distillate. The term volatile can be equally used as “distilling”. Whereas, the terms “non-distilling” or “non-distilled” shall mean ingredients that do essentially not distil over or that are not carried over to the receiving receptacle, as they form the condensate and remain in the still after completion of the distillation process. The dyestuffs of the present invention do essentially not distil over or are not carried over to the receiving receptacle if water and/or alcohol is used as solvent.

In the distillation process according to the invention, the botanical biomass is placed in a suitable receptacle inside a still. The biomass is then submerged in water or in a freely water soluble solvent, such as an alcohol. An operative mixture of biomass and water or such freely water soluble solvent that can be used in the still may be within the range of 1 to 0.5, to 1 to 0.25 ratio by weight of biomass in water or such freely water soluble solvent.

In the hydro-distillation, the alcoholic or the hydro-alcoholic distillation process according to the invention, the botanical biomass is placed in a suitable receptacle inside a still. The biomass is then submerged in water, in alcohol, or a mixture thereof, or in a freely water soluble solvent, other than alcohol, and water. An operative mixture of biomass and solvent, i.e. water or the mixture of water and the freely water soluble solvent that can be used in the still may be within the range of 1 to 0.5, to 1 to 0.25 ratio by weight of biomass in the solvent, i.e. water or the mixture of the freely water soluble solvent and water.

Alcohols that can be used according to the present invention are methanol, ethanol, isopropanol or 2-propanol, 1-propanol, isobutanol, 1-butanol. Preferred alcohol according to the invention described herein is ethanol.

In an alternative embodiment, the biomass is not submerged in the solvent, such as water or a freely water soluble solvent, but is retained in a vessel that has at its bottom an entry for a hot solvent or steam, which, during the process, is forced from below into the vessel containing the biomass. This lower entry may comprise a second vessel that can act both as a source of solvent and as a means for retaining and recovering the residual liquid post-distillation.

The mixture of biomass and water is then heated for a time period sufficient to extract the volatile fraction, including the oil. Depending on the nature of the botanical biomass and the part of the plant being extracted, this can take about 1 hour up to several days. For example, if flower petals are used as the botanical biomass then the process may run for a relatively short time, for example about 1 to 5 hours. The time can be increased to several days if the biomass is more recalcitrant, for example wood bark or wood logs. By running the hydrodistillation process for an appropriate time, and at an appropriate temperature the biomass will release its valuable volatile ingredients, including oils which are driven upwards in the still, on a column of water or solvent vapour to be condensed and finally separated from the water or solvent vapour, or collected as such. The water or solvent vapour itself is condensed and partly captured in the bottom of the still as a water or solvent containing phase. The condensed volatile ingredient including oils can then be collected and valorized in, for example, the fragrance, flavour, cosmetic, medical, nutritional or well-being industries, as appropriate. In prior art distillation processes, it is conventional that the aqueous or solvent-containing medium captured in the bottom of the still (often referred to as the still bottoms) would be discarded as waste, or treated and composted. However, the applicant found that the process of distillation, hydro-distillation, hydro-alcoholic or water steam and/or alcoholic steam distillation is not only effective as a means of separating valuable volatile ingredients including oils from a biomass. At the same time, it also effectively liberates hydrophilic, non-volatile or non-distilling and highly coloured materials from the biomass in sufficiently high yields to enable the aqueous and/or an alcoholic phase to be recovered from the liquid residue waste stream used as a dyestuff to colour textiles.

Typical of the botanical biomasses employed in the extraction of volatile ingredients including oils useful in, for example, the fragrance, flavour and cosmetic industries, they yield highly coloured still bottoms that contain dyestuffs of chemical classes selected from the group consisting of anthraquinones, flavonoides, flavonones, flavonols, tannin derivatives and anthocyanins. Representative examples of these classes of molecules are selected from the group consisting of quercetin, kaemferol, rhamnetin, apigenin, luteolin, aurone, chaicone, carminic acid, pseudopurpurin, purpurin, brazilein, haematein, cyanidin, pelargonidin, delphinidin, peonidin, petunidin, malvidin, tannic acid, gallic acid and ellagic acid.

Typical concentrations of a dyestuff as described in the present invention contained in aqueous and/or alcoholic solution can be between 0.01 and 10 wt%, more particularly between 0.1 and 5 wt%.

The exhausted biomass can be drained and removed from the still. Optionally, the remaining aqueous and/or alcoholic phase containing the dyestuff can be concentrated by evaporation in order to create a solution that is more economical to transport, and also to be presented in an appropriate concentration for storage in a dyeing facility and for any subsequent textile dyeing steps. Preferably, the evaporation step can be carried out in the still as this provides the advantage that the accumulated heat from the extraction process can be utilized to concentrate the aqueous and/or alcoholic solution. By means of the evaporation step, the aqueous and/or alcoholic solution may be concentrated to any desirable extent. In particular embodiments, a 2-fold to 20-fold evaporation can be carried out, more particularly a 5-fold to 15-fold evaporation, even more particularly a 5-fold to 10-fold evaporation.

The applicant found that in a process of alcoholic distillation to extract a volatile ingredient including oil fraction from a botanical biomass, dyestuff molecules were likewise liberated from the biomass, dissolved in the alcoholic bottom still solution Thereafter, the down-stream processing steps of collecting the alcoholic solution, as well as the optional evaporation step, and the preservation step may be the same as the down-stream process described above with regard to the hydro-distillation process. In particular, and preferred embodiments, 5-fold to 50- fold evaporation can be carried out, more particularly a 15-fold to 50-fold evaporation in order to obtain a highly concentrated alcoholic solution containing the dyestuff which is microbiologically stable (without the addition of further preservatives as defined herein below) and which is ready to use in a dye aqueous bath at industrial dyers’ facilities.

An evaporation apparatus may be employed to carry out this step, including simple double layer distillation stills, film evaporators, nucleate boiling evaporators, flash evaporators and direct contact evaporators. Other concentration technologies can also be employed, for example membrane technologies.

The standard distillation apparatus suitable for a process according to the present invention comprises a first receptacle, or a first receptacle having more than one parts or chambers that are connected, characterized in that it comprises the botanical biomass and, at least temporarily, comprising also a liquid residue - partly from the partial backflow of the distillation solvent and/or from maceration, this first receptacle being connected to a condenser being a means for condensing the volatile ingredient of the solvent generated during the distillation process, and a second receptacle following the condenser to receive the distillate of the process from the condenser. Typically, the first receptacle is called the still which comprises the valuable liquid residue and the solid residue of the still, called the still bottoms. The liquid residue being the relevant waste stream which the present invention utilizes to provide the dyestuff from. The first receptacle, containing the botanical biomass is suitable to take up a solvent of up to 30 times the volume of the biomass in addition to the biomass. The first receptacle may have several openings and valves for loading and discharging, particularly for passing through solvents or particularly steam or alcoholic steam and for discharging the still liquid residue during the distillation process or after completion. The condenser can be any apparatus suitable to provide a cooling surface for the evaporated solvent to condense at, such as a glass or a metal cooler, a glass or a metal condenser, such as a Liebig condenser, a reflux condenser or any other condenser known or established in the art. The second receptacle may be one receptacle with several chambers or several receptacles, all having several openings or valves for collecting the valuable volatile and basically also lipophilic ingredients including oils which are transported from the first receptacle to the second receptacle by the evaporating the solvent during distillation, or for discharging unwanted substances of the distillation process.

The aqueous and/or alcoholic dyestuff composition or solution containing the dyestuff can be stabilized against microbial contamination and degradation by the addition of a suitable preservative, before being presented for a subsequent textile dyeing step. In particular embodiments of the invention, the process of preparing the dyestuff comprises the steps of: i. providing a botanical biomass containing an oil useful as a flavour, fragrance, cosmetic, medicinal or wellness ingredient; ii. subjecting the biomass to a process of steam-distillation to separate an oil-containing phase from an aqueous phase containing the dyestuff; and iii. recovering the dyestuff in an aqueous solution.

In particular embodiments of the invention, the process of preparing the dyestuff comprises the steps of: i. providing a botanical biomass containing at least one volatile ingredient, including an oil, selected from a flavour, a fragrance, a cosmetic, a medicinal or nutritional ingredient; and a natural dyestuff; ii. subjecting the biomass to a process of steam-distillation to separate said volatile ingredient, including an oil, and not including the natural dyestuff, from the liquid residue containing the dyestuff; and iii. recovering the natural dyestuff in an aqueous solution from said liquid residue.

The process of steam distillation is substantially the same as that of distillation, hydrodistillation, alcoholic or hydro-alcoholic distillation described above. However, instead of using water or the freely water soluble solvent to separate a volatile ingredient, including oil, from the biomass by submerging the biomass in water or a freely water soluble solvent, steam of water or the freely water soluble solvent is passed over it. Steam distillation processes can achieve higher temperatures than employed in a distillation, hydro-distillation or hydro-alcoholic distillation process, and the choice of distillation, hydro-distillation, alcoholic or hydro-alcoholic distillation or a corresponding steam distillation can be made depending on the particular biomass employed, and the particular parts of the plants that are to be extracted.

In particular embodiments of the invention, the process of preparing the dyestuff comprises the steps of: i. providing a botanical biomass containing at least one volatile ingredient, including an oil, selected from a flavour, a fragrance, a cosmetic, a medicinal or nutritional ingredient; and a natural dyestuff; ii. subjecting the biomass to a process of alcoholic steam-distillation to separate said volatile ingredient, including an oil, and not including the natural dyestuff, from the liquid residue containing the dyestuff; and iii. recovering the natural dyestuff in an alcoholic solution from said liquid residue.

In a process of steam or alcoholic steam distillation, a botanical biomass and the volatile and/or lipophilic ingredients, including oils, it contains are separated from the biomass on a rising stream of steam that passes over and through the biomass. The volatile ingredients including the oils are condensed in a condenser and collected in a separate chamber. The same considerations for the duration of distillation apply as those described above in relation to distillation, hydro-distillation or hydro-alcoholic distillation.

The applicant found that in a process of steam distillation, either a water steam or alcoholic or hydro-alcoholic steam distillation, to extract a volatile ingredient including oil fraction from a botanical biomass, dyestuff molecules were likewise liberated from the biomass, dissolved in aqueous droplets formed on the biomass residue. These droplets can be rinsed off the biomass such that the rinse water or alcohol forms an aqueous solution containing the dyestuff in the bottom of the still. Typically, one might use anywhere between zero and 200 kg of rinse water to separate the dyestuff from 100kg of the biomass residue. Thereafter, the down-stream processing steps of collecting the aqueous or alcoholic solution, as well as the optional evaporation step, and the preservation step may be the same as the down-stream process described above with regard to the hydro-distillation or the alcoholic distillation process.

The applicant also found that in a process of alcoholic or hydro-alcoholic steam distillation to extract a volatile ingredient including oil fraction from a botanical biomass, dyestuff molecules were likewise liberated from the biomass, dissolved in the alcoholic or hydro-alcoholic bottom still solution Therefore, everything said about the down-stream processing steps of collecting the alcoholic solution also applies to the alcoholic or the hydro-alcoholic steam distillation.

Preservatives as used in the present invention can be selected from, but are not limited to, alcohols, such as ethanol, 3-phenyl propanol, octane-1 , 2-diol, propane-1 , 3-diol, citric acid, ascorbic acid, sodium benzoate, potassium sorbate, and mixtures thereof.

The process of the present invention using the step of steam-distillation can be used to yield aqueous and/or alcoholic solutions of dyestuffs of various chemical classes including anthraquinones, flavonoides, flavonones, flavonols, tannin derivatives and anthocyanins. Representative examples of molecules falling within these chemical classes include but are not limited to quercetin, kaemferol, rhamnetin, apigenin, luteolin, aurone, chaicone, carminic acid, pseudopurpurin, purpurin, brazilein, haematein, cyanidin, pelargonidin, delphinidin, peonidin, petunidin, malvidin, tannic acid, gallic acid and ellagic acid.

In particular embodiments of the present invention the process of preparing the dyestuff comprises the steps of: i. providing a botanical biomass containing an oil useful as a flavour, fragrance, cosmetic or medicinal ingredient; ii. treating the biomass with an organic solvent in which the oil is soluble to form an oilcontaining phase; iii. separating the oil-containing phase from the biomass; iv. subjecting the biomass to a process of steam distillation to remove any residual solvent from the biomass and to create an aqueous phase containing the dyestuff; and v. recovering the dyestuff in an aqueous solution.

In particular embodiments of the present invention the process of preparing the dyestuff comprises the steps of: i. providing a botanical biomass containing at least one volatile ingredient, including an oil, selected from a flavour, a fragrance, a cosmetic, a medicinal or a nutritional ingredient; and a natural dyestuff; ii. treating the biomass with an organic hydrophobic solvent in which the at least one volatile ingredient, including the oil, is soluble to form an oil-containing phase; iii. separating the oil-containing phase from the biomass; iv. subjecting the biomass to a process of steam distillation to remove any residual solvent of step (ii) from the biomass and to create an aqueous phase as liquid residue containing the natural dyestuff; and v. recovering the natural dyestuff in an aqueous solution from said liquid residue.

In particular embodiments of the present invention the process of preparing the dyestuff comprises the steps of: i. providing a botanical biomass containing at least one volatile ingredient, including an oil, selected from a flavour, a fragrance, a cosmetic, a medicinal or a nutritional ingredient; and a natural dyestuff; ii. treating the biomass with an organic hydrophobic solvent in which the at least one volatile ingredient, including the oil, is soluble to form an oil-containing phase; iii. separating the oil-containing phase from the biomass; iv. subjecting the biomass to a process of water, alcoholic and/or hydro-alcoholic steam distillation to remove any residual solvent of step (ii) from the biomass and to create an aqueous and/or alcoholic phase as liquid residue containing the natural dyestuff; and v. recovering the natural dyestuff in an aqueous and/or alcoholic solution from said liquid residue.

In a particular embodiment of the present invention, the process of preparing a dyestuff comprising the steps of: i. providing a botanical biomass containing at least one volatile ingredient, including an oil, selected from a flavour, a fragrance, a cosmetic, a medicinal or a nutritional ingredient; and at least one natural dyestuff; ii. treating the biomass with an organic hydrophobic solvent in which the at least one volatile ingredient, including the oil, is soluble to form an oil-containing phase; iii. separating the oil-containing phase from the biomass; iv. heating the biomass in the presence of water and/or alcohol to remove any residual solvent of step (ii) from the biomass, and providing a solid residue and a liquid residue containing the dyestuff and v. recovering the natural dyestuff in an aqueous and/or alcoholic solution from said liquid residue.

In a particular embodiment of the present invention, the process of preparing a dyestuff comprising the steps of: i. providing a botanical biomass containing at least one volatile ingredient, including an oil, selected from a flavour, a fragrance, a cosmetic, a medicinal or a nutritional ingredient; and at least one natural dyestuff; ii. treating the biomass with an organic hydrophobic solvent in which the at least one volatile ingredient, including the oil, is soluble to form an oil-containing phase; iii. separating the oil-containing phase from the biomass; iv. heating the biomass in the presence of water and/or alcohol and subjecting it to a water, an alcoholic and/or a hydro-alcoholic steam distillation to remove any residual solvent of step (ii) from the biomass, and providing a solid residue and a liquid residue containing the dyestuff and v. recovering the natural dyestuff in an aqueous and/or alcoholic solution from said liquid residue.

In a process of solvent extraction described above, the botanical biomass is placed in a still and is steeped in a suitable organic solvent selected on the basis of its ability to dissolve the volatile ingredients including oil that is sought. In this manner, the volatile ingredient, including an oil, is taken-up into the solvent and separated from the biomass. This process may take as little as up to one hour or as much as several days, and at a temperature ranging from room temperature to about 70°C to about 100°C, depending on the type of botanical employed. Suitable organic solvents include, but are not limited to hydrophobic and/apolar solvents, and in particular those selected from the group consisting of hexane, heptane, cyclohexane, toluene, ethyl acetate, dichloromethane, dimethyl carbonate, methyl esters of fatty acids, or mixtures thereof.

Applicant discovered in a surprising manner that through the judicious selection of the organic solvent, it is possible to separate the volatile ingredients, including the oil, from the biomass, whilst at the same time retaining the dyestuff in the biomass.

After solvent treatment to separate the volatile ingredients, including the oil, the biomass is saturated with solvent. The biomass can be steam-distilled to remove the solvent, also referred to as desolventation. Normally, removal of the solvent is carried out in order to prepare the biomass waste for compositing in an operation that can take from as little as about one hour or for as long as several hours. However, the applicant discovered that as a result of the steamdistillation process, the dyestuff leaches out of the biomass and forms in droplets of water on the biomass residues. These droplets can be collected as an aqueous solution containing the dyestuff as such at the still bottom or by rinsing the biomass residues as described above.

The dyestuffs extracted by such a process as described in the present invention include those of the chemical classes including anthraquinones, flavonoides, flavonones, flavonols, tannin derivatives and anthocyanins. Representative compounds selected from these chemical classes include but are not limited to quercetin, kaemferol, rhamnetin, apigenin, luteolin, aurone, chaicone, carminic acid, pseudopurpurin, purpurin, brazilein, haematein, cyanidin, pelargonidin, delphinidin, peonidin, petunidin, malvidin, tannic acid, gallic acid and ellagic acid. The dyestuffs may be present in aqueous and/or alcoholic solution in a concentration of between about 0.01 and about 30 wt%, and more particularly between about 1 and about 10 wt%.

Another particular embodiment of this invention is that the process as described herein provides a natural dyestuff that comprises an anthraquinone, a flavonoide, a flavonone, a flavonol, a tannin derivative or an anthocyanin.

In accordance with the processes of the present invention, the dyestuff is removed from the still in the form of an aqueous and/or alcoholic solution, which is optionally concentrated by evaporation, and prepared for textile dyeing in the same manner as described above in relation to the process of steam distillation.

The aqueous and/or alcoholic solutions containing these natural dyestuffs form additional aspects of the present invention.

It will be understood by the skilled person in the art that the processes according to the present invention are modifications of existing processes for extracting botanical materials to obtain volatile ingredients including oils of great interest to the food, beverage, fragrance, flavour, cosmetic, medicinal and well-being industries. The applicant found that many botanicals not generally known or exploited for their tinctorial properties, but which are widely used in the food, beverage, fragrance, flavour, cosmetics, medicinal, nutritional or well-being industries could be used to obtain natural dyestuffs in sufficiently high yields to be useful in the textile dyeing industry increasing efficiency yield of the botanical biomasses.

The present invention can be carried out on all manner of botanical biomasses, including but not limited to rose, clove, violet, sandalwood, onions, peppermint, chamomilla, lavandin & lavender, tagetes, jasmine, neroli, ylang-ylang, mint, leek, eucalyptus (leaves), basil, melissa, carrot, apricot, cherry, plum, apple, pear, lemon grass, orange mandarin, grapefruit, (key) lime, calendula, genepi, yarrow, dill, aniseed, chervil, cacao, cardamom, cassia bark, caraway, celery, cinnamon bark, cistus, coffee, coriander, cumin, fennel, guaiacwood, myrrh, olibanum, patchouli, schinus molle, styrax, tea, pepper, cedar wood, chicoree, citrus, cranberry, elemi, ginger, hibiscus, oakmoss, olive, orange, grape, yerba mate, red wine, petitgrain, rose wood, pine, cypress, rosemary, sage, thyme, oregano, majoram, lovage, tonka, quillaja, geranium, mushrooms and algae.

Preferably the botanical biomasses are selected from clove, violet, sandalwood, onions, peppermint, chamomilla, lavandin & lavender, tagetes, jasmine, neroli, ylang-ylang, mint, leek, eucalyptus (leaves), basil, melissa, carrot, apricot, cherry, plum, apple, pear, lemon grass, orange mandarin, grapefruit, (key) lime, calendula, genepi, yarrow, dill, aniseed, chervil, cacao, cardamom, cassia bark, caraway, celery, cinnamon bark, cistus, coffee, coriander, cumin, fennel, guaiacwood, myrrh, olibanum, patchouli, schinus molle, styrax, tea, pepper, cedar wood, chicoree, citrus, cranberry, elemi, ginger, hibiscus, oakmoss, olive, orange, grape, yerba mate, red wine, petitgrain, rose wood, pine, cypress, rosemary, sage, thyme, oregano, majoram, lovage, tonka, quillaja, geranium, mushrooms and algae.

Preferably, the different botanical biomasses are provided in the form of petals (e.g. rose), leaves (e.g. clove, violet, (peppermint, basil, eucalyptus, chervil, coriander, celery, geranium, patchouli, schinus molle, tea, leek, melissa, sage, lovage, hibiscus, mate), wood (e.g. sandalwood, guaiacwood, cedar wood, rose wood, pine wood, petitgrain), bulb (e.g. onions), flowers (e.g. lavandin, lavender, calendula, cistus, tagetes, jasmine, neroli, ylang-ylang, melissa), herbage (e.g. lemon grass), beans (e.g. cacao, coffee, tonka), seeds (e.g. cardamom, celery, coriander, cranberry, cumin, dill, carrot, caraway, fennel), bark (e.g. cinnamon, cassia bark, quillaja), resin (e.g. elemi, myrrh, olibanum, styrax), fruit (e.g. schinus molle, apricot, cherry, plum, apple, pear, grapes), berries or corns (e.g. pepper), aerial parts (e.g. thyme, genepi, yarrow, majoram, oregano, rosemary), root (e.g. ginger, lovage), or rind (e.g. orange, orange mandarin, grapefruit, citrus, lime) or mixtures thereof.

The simultaneous one-pot or single-step extraction of both, the valuable volatile ingredient including oil and the dyestuff in the same distillation process or even apparatus is advantageous for all of the economic and environmental reasons set out above. However, in addition to these advantages, carrying out the extraction of dyestuffs concomitantly with the extraction of the valuable volatile ingredient, including an oil, means that the biomass has been subjected to less processing steps and as such, the tone, tint and shade of the colours obtainable can be improved.

In a particular embodiment of the present invention the botanical biomass used in the process according to the invention described herein is selected from the group consisting of rose, clove, violet, sandalwood, onions, peppermint, chamomilla, lavandin & lavender, tagetes, jasmine, neroli, ylang-ylang, mint, leek, eucalyptus leaves, basil, melissa, carrot, apricot, cherry, plum, apple, pear, grapes, lemon grass, orange mandarin, grapefruit, lime, calendula, genepi, yarrow, dill, aniseed, chervjl, cacao, cardamom, cassia bark, caraway, celery, cinnamon bark, cistus, coffee, coriander, cumin, fennel, guaiacwood, myrrh, olibanum, patchouli, schinus molle, styrax, tea, pepper, cedar wood, chicoree, citrus, cranberry, elemi, ginger, hibiscus, oakmoss, olive, orange, yerba mate, red wine, petitgrain, rose wood, pine, cypress, rosemary, sage, thyme, oregano, majoram, lovage, tonka, quillaja, geranium, mushroom and algae. With the present invention, if something is transported it is not the high volume solid waste biomass that needs to be dried to avoid microbial degradation, it is a concentrated aqueous and/or alcoholic solution of the dyestuff which is easy to handle, easy to transport, and all at low cost.

In another particular embodiment, the volatile ingredient obtained by the process described in the present invention is at least an essential oil for use as a flavour or as a fragrance.

Essential oils as provided by the present invention can be used as a flavour or a fragrance in countless applications, including but not limited to for flavouring spirits, or for aromatherapy.

In another particular embodiment of the present invention, the distillation process according to the invention described herein can be selected from a hydro-distillation, an alcoholic distillation, a hydro-alcoholic distillation, a water steam distillation, an alcoholic steam distillation or a hydro-alcoholic steam distillation, preferably the distillation is selected from a hydro-distillation, a hydro-alcoholic distillation, a water steam distillation, an alcoholic steam distillation or a hydro-alcoholic steam distillation.

In yet another particular embodiment, the liquid distillate comprising the at least one volatile ingredient, including an oil, and the liquid residue of the still are provided simultaneously. And the process according to the present invention as defined hereinabove may be a single-step process.

In another particular embodiment, the liquid residue containing said aqueous and/or alcoholic solution of the natural dyestuff provided by the process described hereinabove is further concentrated.

In yet another particular embodiment, the concentrated liquid residue containing said aqueous and/or alcoholic solution of the natural dyestuff provided by the process described hereinabove is further microbiologically stabilized.

Another particular embodiment of the present invention provides an aqueous and/or alcoholic solution comprising a dyestuff according to the process of the present invention which is characterized in that the dyestuff is recovered from the liquid residue of the still of said distillation process of said botanical biomass.

By means of a portable distillation still, the process according to the present invention could be carried out in the immediate vicinity of a botanical crop. Once harvested, a botanical biomass could be immediately fed into the still and extracted to provide concomitantly, both a valuable volatile ingredients including oil and also an aqueous and/or alcoholic solution containing a dyestuff. A portable laboratory comprising a distillation unit, and optionally other equipment to carry out other down-stream operations on the volatile ingredients including oil and dyestuff such as water evaporation and analytical measurements, forms another aspect of the present invention.

Textiles as understood in the present invention include various fiber-based materials, including but not limiting yarn, filaments, threads and different fabric types, no matter if the textiles have been newly made and/or factory-made or recycled.

The dyeing of textiles using the aqueous and/or alcoholic solutions containing dyestuffs obtained according to the methods described herein can be carried out according to dyeing processes generally known in the art. All manner of textiles can be dyed in accordance with the present invention, including but not limited to protein or protein based fibres, such as wool and silk, cellulosic or cellulose based fibres such as cotton, linen, flax and hemp, but also viscose and lyocel, and synthetic polymer based fibres, such as polyamide fibre.

Accordingly, use of the dyestuffs obtained according to the processes described herein to colour textiles and fabrics, as well as the coloured textiles and fabrics form additional aspects of the present invention.

Another particular embodiment of the present invention as described hereinabove is the use of the aqueous and/or alcoholic solution as defined herein for colouring a textile, a yarn and/or a fabric wherein the textile, yarn and/or the fabric is selected from group consisting of those containing proteinic fibers, including wool or silk, and those containing cellulosic fibers, including cotton or linen.

In a typical dyeing process, a textile, yarn and/or fabric is passed through and soaked in the aqueous solution containing the dyestuff. The aqueous and/or alcoholic dyestuff solution of the present invention may be diluted, for example in water, before using it for dyeing. This may be carried out at ambient temperature, or at elevated temperature, for example between about 20 to about 150°C, and the dyeing process may proceed through a temperature gradient of gradually increasing and/or decreasing the temperature.

The aqueous and/or alcoholic solution comprising the dyestuff may also contain common auxiliaries, such as wetting agents, typically used in dyeing processes.

The dyestuffs prepared in accordance with the present invention may display varying levels of substantivity on textiles and fabrics, and it may be desirable to employ mordants in the dyeing process. Mordants create an affinity between the textile or fabric fibres and the dyestuff molecules. Mordanting can be achieved according to methods generally known in the art, for example by pre-mordanting (before dyeing), simultaneously mordanting and dyeing, or by post-mordanting (after dyeing). Different types of mordants can be applied on a textile or fabric to increase the dye uptake of natural dyes, or to affect the quality of dyeing, for example adjustment of the hue.

Mordants are typically metal salts that form complexes between the fibres of a textile or fabric and the dyestuff molecules. After mordanting, the metal salts anchoring to the fibres, attract the dye molecules to be anchored to the fibres and finally creates the bridging link between the dye molecules and the fibre by forming coordinating complexes. Aluminium sulphate or other metallic mordants anchored to any fibre, chemically combine with certain mordantable functional groups present in the dye molecules and bind by coordinated/covalent bonds or hydrogen bonds or other interaction forces.

Suitable metal salts include aluminium potassium salts, such as aluminium potassium sulphate dodecahydrate, iron (II) salts, such as ferrous sulphate heptahydrate, and chromium potassium sulphate, calcium salts such as calcium chloride, calcium carbonate.

But also ecological plant-based mordants can be used such as plant-based tannic acid, or turmeric, acacia, pomegranate and/or mimosa extracts.

After dyeing, a washing step can be performed to remove any unfixed dye molecules.

The dyestuffs obtained according to a process of the present invention display affinity for textiles or fabrics, preferably proteinic or protein based fibers like wool or silk or cellulosic or cellulose based fibers like cotton or linen more preferably proteinic or protein based fibers like wool or silk with good fastness properties, e.g. wet, rub and light fastness. However, the greatest interest and main characteristic of this invention comes from the fact that the dyestuffs enable the dyeing of textiles or fabrics in a sustainable way, avoiding the use of toxic compounds, and reducing the CO2 generation in comparison with present known procedures of the prior art. According to the present invention, the dyestuffs obtained by the present process result in homogeneously dyed textiles without using chemical additives, such as toxic synthetic levelling agents which are required in synthetic reactive dyes, in order to guarantee homogenized shades without any stains. In addition, the dyestuffs of the present invention are pH neutral and do not require high level of acids (pH < 2) as synthetic reactive dyes do, and which require again additional treatment in the waste water treatment plant. Finally, the dyestuffs of the present invention are readily biodegradable avoiding the release of toxic and cumulative substances into the environment.

The aqueous and/or alcoholic solutions containing a dyestuff formed according to a process according to the present invention are capable of delivering vibrant colours to textiles and fabrics, such as yellow or yellowish, brown or brownish, grey or greyish, green or greenish, orange or black hues.

In general, colours can be described by the CIE LAB colour space (CIE stands for Commission on Illumination) according to the standard as defined in ISO/CIE 11664-4-2019 wherein the colour space is expressed as three values L* for “Luminosity” expressing the gradient of lightness from black (0) to white (100), a* or “A” from green (-) to red (+), and b* or “B” from blue (-) to yellow (+) to visualize the numerical change of colour roughly the same amount of the visually perceived change of colour. This means the higher the a* or “A” value the redder it is perceived. A neutral grey would be expressed as an a* or “A” value and a b* or “B” value of (0) each. Brown tones would have a low L* value and a higher a* or “A” value.

By adjusting the type of mordant and the concentration of dyestuff in the aqueous solution, one can influence the shade, tint or tone of coloured textiles and fabrics.

For example, when wool is dyed with aqueous and/or alcoholic solutions obtained from rose petals as botanical biomass according to the process according of the present invention typically a brown shade is obtained. But when aluminium potassium sulphate is employed as a mordant a yellow shade can be obtained. Similarly, when iron (II) sulphate heptahydrate is employed as the mordant, a dark grey to black shade can be obtained. Other shades can be obtained by varying the concentration and types of mordant employed in the dyeing process.

Some further particular embodiments of the present invention are:

A process according to the invention described herein, wherein the natural dyestuff recovered in an aqueous and/or alcoholic solution from said liquid residue is a non-distilled natural dyestuff.

The textile, yarn or fabric coloured with an aqueous and/or alcoholic solution according to the present invention defined herein.

An aqueous solution comprising a dyestuff obtained by the process according to the present invention. An aqueous solution according to the present invention described herein comprising an anthraquinone, a flavonoide, a flavonone, a flavonol, a tannin derivative or an anthocyanin.

The use of an aqueous solution as defined hereinabove for colouring a textile, yarn or fabric.

The use of such aqueous solution as defined hereinabove, wherein the textile, yarn or fabric is selected from the group consisting of those containing proteinic fibers, including wool or silk, and those containing cellulosic fibers, including cotton or linen.

A textile, yarn or fabric coloured with an aqueous solution according to invention defined hereinabove.

A portable apparatus for conducting a process as defined herein.

The invention will be further illustrated by reference to the following examples.

Examples

Example 1a - Fragrance & colour extraction process from rose biomass

Extraction with hydrophobic solvent:

20kg of fresh rose petals are placed in a still and are submerged in dimethyl carbonate. The mixture is agitated for several hours.

The dimethyl carbonate extract is then collected and subjected to vacuum processing to remove the solvent for re-use. The remaining waxy mass which is called a rose concrete is then mixed with alcohol to remove the wax and other substances by filtration. The alcohol is then evaporated to give the absolute which could be used for fragrances or cosmetics formulations.

Distillation process:

The rose petals as waste stream biomass of the above extraction process are treated with steam for 1 hour to drive off any remaining dimethyl carbonate. At the end of the operation, 13kg of coloured condensed water with a dried substance content of 2% are recovered and collected from the still. The residue is then washed with water before being removed from the still. The washings are added to the condensed water. The solvent free exhausted biomass is composted.

Stabilization:

Thereafter, 20g of citric acid and 75g of Sensiva PA40 is added to the coloured aqueous solution. After 10 min stirring the resulting dyeing solution is filtered and packed. The solution can be characterized using a spectrophotometric colourimeter (Lovibond PFX195) following the ASTM E308 method. The CIE lab values for the solution were measured to be a 15 b 62 L 58.

Example 1b - Dyeing of wool

The coloured aqueous solution in combination with traditional and eco-friendly mordants (ferrous sulphate or aluminium potassium sulphate) is used as such to dye natural white wool according to the following procedure:

A swatch of wool (0.5kg) is soaked in the coloured aqueous solution (4 kg) obtained according to the process of Example 1 at 20°C for 10 minutes. Thereafter, the temperature of the solution is increased to 95°C at a rate of 2°C per minute. The textile is soaked for 15 minutes at 95°C before a mordant is added (aluminium potassium sulphate 0.02kg). After the addition of the mordant, the textile remains soaked in the solution for a further 35 minutes at 95°C. Finally, the solution is cooled to 70°C before it is drained from the textile, and the textile washed. After drying, a deep yellow wool is obtained.

Example 1c - Wash-Fastness

Wash-fastness was determined at 40°C according to DIN 54014. The standard detergent washing liquors employed were L-1 FAS (0.45g. L-1), sodium lauryl sulphate (0.5 g L-1 APG) and alkyl polyglycoside. The dyed samples (1g) were treated for 30 min at 40 °C with 50g of standard detergent washing liquor.

After rinsing and drying, the change in colour of the samples was determined visually. The changes were related to a standard scale (marks 1-5, 1 = poor, 5 = excellent). The results of the test established that the wash-fastness of the recovered dyestuff from the rose petals according to the process of example 1 was excellent (= 5).

Example 2a - Upcycled dyes from rose petals and its use - distillation process

A 3000L hydro-distiller is filled with fresh petals of rose de Mai (500kg) and water (1500L). The steam jacket is used for distillation and the distillation process was run during 1 hour and 30 minutes.

Through this process 650kg of Rose water (hydrolate) carrying rose oil are produced. The Rose water can be used in fragrances or cosmetics formulations.

650kg of brown coloured waste water residue are generated during the process and collected from the bottom of the hydro distiller. Example 2b - Upcycled dyes from rose petals and its use - concentration and stabilization process

These 650 kg of coloured waste water residue are transferred into an industrial evaporator and concentrated 15 times (100°C, Atmospheric pressure, evaporation time 2 hours) to obtain 43kg of concentrated brownish coloured solution.

Preservatives (43g of citric acid, 86g of sodium benzoate and 86g potassium sorbate) are then added to obtain the final rose petals upcycled natural dye which is microbiologically stable, biodegradable, non-classified as dangerous goods, and which can be used as such for textile dyeing.

Microbial analysis results:

The microbiological analysis of the upcycled natural dye confirm the absence of microorganism at tO:

Total Aerobic Microbial Count < 10 cfu/g Current Ph. Eur.

Total Combined Yeasts/Moulds < 10 cfu/g Current Ph. Eur.

Count Bile-tolerant gram-negative bacteria Not Detected /1g Current Ph. Eur. The dyestuff solution passes successfully the challenge tests (ISO 11930.2019 criteria A & B validated) and demonstrate the resistance regarding microorganism proliferation

Example 2c - Upcycled dyes from rose petals and its use - dyeing process

The rose petals upcycled natural dye is used as such in a standard industrial dye bath equipment to dye 10kg of 100% natural white wool textile according to the following procedure:

1 .07kg of the rose petals upcycled natural dye is put into the industrial dye bath and diluted with 77kg of water. The industrial dye equipment is then loaded with 10kg of wool (1 m width). The textile is soaked for 10 min at room temperature (fabric circulating). Thereafter, the temperature of the solution is increased to 95°C at a rate of 2°C then a mordant solution (3.3kg, 120 g/L): potassium alum solution or ferrous sulphate heptahydrate is added and the textile remains soaked in the solution for a further 35 minutes at 95°C. Finally, the dye bath is cooled to 70°C before it is drained from the textile. The pH of the remaining dye bath is 6 and does not require any neutralization step usually required when synthetic reactive dyes are used. Finally, the dyed wool textile is washed. And as a last step the textile is dried.

A deep yellow wool homogeneous textile (without any stain) is obtained when potassium alum was used as mordant solution (Fig. 2) and a dark grey wool homogeneous textile (without any stain) is obtained when ferrous sulphate heptahydrate was used as mordant solution (Fig. 3).

Example 2d - Upcycled dyes from rose petals and its use - Fastness tests

Wash-fastness was determined according to the same method as described in example 1c with the standard detergent. In addition, fastness was determined with a washing liquor simulating a phosphate containing detergent according to ISO 105 C062010 (Test number A2S), the ECE stimulating phosphate detergent having the following composition: sodium alkylbenzenesulphonate (mean chain length of C11 ,5), ethoxylated tallow alcohol, sodium soap with up to 26% of C12-C16 and up to 87% of C18-C22, sodium tripolyphosphate, sodium silicate, magnesium silicate, carboxymethylcellulose, ethylendiaminetetraacetic acid sodium salt, sodium sulphate and water.

Furthermore, a fastness test to dry cleaning was conducted according to ISO 105 D01 2010. The colour loss and staining resulting from desorption are evaluated on the dyed yellow sample following different protocols and the results are presented below in table 1. The changes were related to a standard scale (marks 1-5, 1 = poor, 5 = excellent).

Table 1 : Results of the colour fastness tests

Example 3a - Upscaled dyes from clove leaves and its use - distillation process

A 500L hydro-distiller is filled with fresh clove leaves (300kg). The steam jacket is used for distillation and the distillation process was run during 6 hours. Through this process 7kg of clove oil which could be used in fragrances or cosmetics formulations are produced. 28kg of black waste water residue are generated and collected from the bottom of the hydro-distiller.

Example 3b - Upscaled dyes from clove leaves and its use - Concentration and stabilization

These 28 kg of coloured waste water residue are concentrated 10 times in a double jacket still (100°C, atmospheric pressure, evaporation time 2 hours) to obtain 2.8kg of concentrated black solution.

Preservatives (5.6g of a 0.45:0.25:0.3 mixture of alcohols composed of 3-phenyl propanol I octane 1,2 diol I propanel, 3 diol and 2.8g of citric acid)) are then added to obtain the final clove leaves upcycled natural dye which is microbiologically stable, biodegradable, non-classified as dangerous goods, and which could be used as such for textile dyeing.

Microbial analysis results:

The microbiological analysis of the upcycled natural dye confirm the absence of microorganism at tO:

Total Aerobic Microbial Count < 10 cfu/g Current Ph. Eur.

Total Combined Yeasts/Moulds < 10 cfu/g Current Ph. Eur.

Count Bile-tolerant gram-negative bacteria Not Detected /1g Current Ph. Eur.

Biodegradability results (norm OECD301 F): the product is readily biodegradable with 93% biodegradable after 13 days of testing. Example 3c - Upscaled dyes from clove leaves and its use - dyeing process

The clove leaves upcycled natural dye is used as such in a standard industrial dye bath equipment to dye 1kg of 100% natural white wool textile according to the following procedure:

0.8 kg of the clove leaves upcycled natural dye is put into the industrial dye bath and diluted with 7.2kg of water. The industrial dye equipment is then loaded with 1kg of wool (1m width). The textile is soaked for 10 min at room temperature (fabric circulating). Thereafter, the temperature of the solution is increased to 95°C at a rate of 2°C per minute. The textile is soaked for 15 minutes at 95°C then a Ferrous sulphate heptahydrate mordant solution (333g, 120g/L) is added and the textile remains soaked in the solution for a further 35 minutes at 95°C. Finally, the dye bath is cooled to 70°C before it is drained from the textile. The pH of the remaining dye bath is 6 and does not require any neutralization step usually required when synthetic reactive dyes are used. Finally, the dyed wool textile is washed. After drying a dark grey wool homogeneous textile (without any stain) is obtained.

Example 3d - Upscaled dyes from clove leaves and its use - fastness tests

Fastness tests are applied on the dyed sample according to the same method as described in example 1c and the results are presented in table 2 below.

Table 2: Results of the colour fastness tests

Example 4a - Upscaled dyes from different botanicals - distillation process

General procedure: A 100L to 1000L distiller is filled with 10 to 600kg of a fresh botanical biomass. The list of botanicals and experimental conditions used to provide upscaled dyes are disclosed in table 3 below. The steam jacket is used for distillation, and the hydrodistillation, alcoholic, hydro-alcoholic, the water steam or alcoholic steam distillation process was run during 1 hour to several days. Through this process the respective essential oils, possibly obtained in a water or alcoholic solution, are obtained in the amount as specified in table 3 which then can be used in flavour, fragrance or cosmetic formulations, or for the manufacture of flavoured spirits.

The coloured liquid waste water residues are generated and collected from the bottom of the distiller in yields as provided in table 3 below.

Table 3 - Botanical Biomasses used in Examples 4a - 4c

Example 4b - Upscaled dyes from different botanicals - concentration and stabilization

General procedure:

The coloured liquid waste water residues (as provided in table 3) are concentrated 5- 10 times in a double jacket still (100°C, atmospheric pressure, evaporation time 2 hours) to obtain a concentrated darker coloured solution of about 10% of the initial volume of the liquid waste water residue.

Preservatives (0.6 % by weight of the concentrated natural dyestuff solution of a 0.45:0.25:0.3 mixture of alcohols composed of 3-phenyl propanol, octane-1, 2-diol, propane-1, 3-diol and 0.1% by weight of the concentrated natural dyestuff solution of citric acid) are then added to obtain the final, stabilized upcycled natural dye which is microbiologically stable, biodegradable, non-classified as dangerous goods, and which can be used as such for textile dyeing.

Example 4c - Upscaled dyes from different botanicals - dyeing process

General procedure:

The upcycled natural dye is used as such in a standard industrial dye bath equipment to dye 1kg of 100% natural white wool textile according to the following procedure: 0.05-1kg of the upcycled natural dye is put into the industrial dye bath and diluted with 7-8kg of water. The industrial dye equipment is then loaded with 1kg of wool (1m width). The textile is soaked for 10 min at room temperature (fabric circulating). Thereafter, the temperature of the solution is increased to 95°C at a rate of 2°C per minute. The textile is soaked for 15 minutes at 95°C then a mordant solution to target a mordant dye bath concentration between 1-5g/L is added and the textile remains soaked in the solution for a further 35 minutes at 95°C. Finally, the dye bath is cooled to 70°C before it is drained from the textile. The pH of the remaining dye bath is 6 and does not require any neutralization step. Finally, the dyed wool textile is washed. After drying a coloured homogeneous textile (without any stain) is obtained (Fig. 4 - 8).