Process for dyeing pipe braids

Abstract

A method for dyeing cane weaving, in particular rattan or wicker weaving, with natural dyes or coloring agents, wherein the cane weaving is formed by a plurality of flat strands obtained from the outer skin of a plant shoot and interwoven together, the smooth outer skin surface of which is oriented to one side, thus forming an upper smooth surface and a lower rough surface of the cane weaving, comprises the following steps: a) immersion of the cane weaving in a first immersion bath of an aqueous solution of a natural tanning agent and bathing of the cane weaving in this aqueous tanning agent solution for a first predetermined period; b) removal of the cane weaving from the first immersion bath and preferably allowing the remaining aqueous tanning agent solution to drip off;c) Applying a natural dye or color-active reagents to the reed mesh for a second predetermined period.;

Description

[0001] This PCT application claims priority from the German patent application DE 10 2023 118 877.1 dated July 17, 2023. TECHNICAL AREA

[0002] The present invention relates to a method for dyeing woven cane according to the preamble of claim 1. It further relates to the use of a dyeing method for braided cane according to the preamble of claim 14 and alternatively of claim 15, as well as a cane according to the preamble of claim 16. BACKGROUND OF THE INVENTION

[0003] Cane webbing, such as Viennese cane webbing, is used as a natural raw material for upholstering the seat and / or backrest of seating furniture in its characteristic light, natural color. For design reasons, there is a desire to also use cane webbing in furniture construction in different colors. The goal is for the cane webbing to retain its technical properties while also taking on a different coloration that, in turn, meets the technical requirements for seat upholstery (lightfastness, perspiration resistance, abrasion resistance).

[0004] While technically possible, dyeing the fiber strands used as raw material for the cane weaving is not desirable for quality reasons. This is because the finished cane weaving semi-finished product is sourced from suppliers to the furniture industry, over whose processing quality the furniture manufacturer has virtually no control. To avoid the problem of frequent complaints from the outset, the aim is for the furniture manufacturer to dye the finished cane weaving semi-finished product under their own quality control.

[0005] Applying a coating of color (paint, stain) to the cane weave would seem like the obvious solution, but this method doesn't color the areas where fiber strands overlap. As these fibers shift relative to each other during use, these uncolored areas become visible, making the overall appearance of the cane weave unsightly. The same principle applies to stains. Furthermore, paint applied to the cane weave can rub off over time or even flake off due to the dynamic stresses and vibrations experienced when using a piece of furniture made from it. Therefore, the cane weave should be dyed throughout.

[0006] The fiber strands of the rattan weaving are obtained from the rattan palm and are commonly known as rattan. These fibers are extracted exclusively from the outermost layer, the skin, of the plant shoot. This skin is characterized by a smooth surface and high strength, making it ideal for use as a seat covering, and its smooth surface also forms the visible side of the rattan weaving. However, this surface appears to lack any capillaries or fibers, which increases the difficulty of permanently introducing a dye directly into the surface from the outside.

[0007] The underside of the fiber strands, however, has a typical fibrous structure, similar to that found in rattan furniture. Introducing a dye here is straightforward, but the dye does not penetrate evenly to the surface layer. STATE OF THE ART

[0008] From DE 479 801 A, which deals with the bleaching of chair cane and rattan cane, it is known that the outer surface of chair cane is resistant because silica deposits are present there.

[0009] DE 736 022 A deals with a two-stage process for dyeing dried reeds or other plant parts, wherein the material to be dyed is first treated with a solution of water-soluble salts and then with an aqueous solution of an alkaline agent.

[0010] EP 1 012 374 B1 relates to a method for treating a wood substrate, which in a first step is brought into contact with an aqueous solution containing a metal salt solution and in a second step is brought into contact with an aqueous solution containing a solution of an oxidizing agent. The respective residence times of the wood substrate in the solutions are to be measured such that the substrate is colored or stained.

[0011] EP 3 047 946 A1 discloses and describes a method for treating rattan, in which a rattan rod with longitudinally extending tubes is connected to a pipe system through which it is pressurized with a liquid. This liquid, which is introduced into the rattan rod under pressure, can be, for example, paint. Through this process, the paint is forced from the inside out through the wood of the rattan rod and through its capillaries to color the rattan.

[0012] EP 3 464 401 B1 relates to an aqueous polymer dispersion and a manufacturing process for it, as well as its use in the production of exterior coatings for wood, bamboo, and rattan. Dyeing the material with a natural dye is not intended.

[0013] CN 1 09 623 987 A relates to a process for the production of bamboo products, namely woven goods made from red bamboo. Bamboo discs are soaked in a salt solution for several days, causing the bamboo cells to lose water and allowing salt to accumulate within them, which is said to be advantageous for the adhesion of dyes.

[0014] DE 561 455 A relates to a process for refining veneer wood, in which the wood is first bleached with a highly chlorine-containing hypochlorite solution. This is followed by rinsing with water and a post-treatment with hydrogen peroxide.

[0015] From CN 1 10 509 368 A, a process for producing a complex tablet from plant fibers, plant polyphenol, and metal salts is known. The metal salt is introduced into the plant fibers, thereby changing the color of the plant fibers.

[0016] From CN 1 10 480 764 A a process for producing a composite from individual sheets is known, in which individual sheets are impregnated with plant-based polyphenol and then treated with metal salts.

[0017] From CN 1 10 561 570 A a process for producing an artificial bamboo board is known in which the bamboo board is impregnated with plant-based polyphenol and then treated with metal salts to produce, among other things, a color effect.

[0018] From the non-patented literature available on the Internet, "Tea Staining Baskets" (https: / / www.prairiewoodbasketry.com / index.php / 2016 / 05 / 04 / tea-staining-baskets / ) A method for dyeing wickerwork is known in which the wickerwork is formed from the inner fiber strands of a plant shoot. The wickerwork is moistened with a tea solution and then exposed to fumigation with ammonia vapors. PRESENTATION OF THE INVENTION

[0019] The object of the present invention is to provide an improved method for dyeing already woven cane mesh, which is formed from flat strands obtained from the outer skin of a plant shoot and woven together, and in which the cane mesh can be dyed uniformly and evenly, even where individual strands of the cane mesh overlap.

[0020] This problem is solved by a method having the features of claim 1.

[0021] In a process for dyeing cane weaving, in particular rattan or wicker weaving, with natural dyes or color-active reagents, wherein the cane weaving is formed by a plurality of flat strands obtained from the outer skin of a plant shoot and interwoven with one another, the smooth outer skin surface of which is directed to one side and thus an upper smooth surface and a lower rough surface of the cane weaving are formed, the following steps are provided according to the invention: a) Immersion of the reed mesh in a first immersion bath of an aqueous solution of a natural tanning agent and bathing of the reed mesh in this aqueous tanning agent solution for a first predetermined period, at least until the reed mesh has absorbed the aqueous tanning agent solution and sinks to the bottom of the first immersion bath vessel and / or between one day and two weeks; b) Removal of the reed mesh from the first immersion bath and preferably allowing the remaining aqueous tanning agent solution to drain off; c) Exposure of the reed mesh to a natural dye or to color-active reagents for a second predetermined period of between 12 hours and 24 hours or from 4 to 7 days, or until the reed mesh has absorbed an aqueous solution of the natural dye or the color-active reagents in a second immersion bath vessel and sinks to the bottom of the second immersion bath vessel.

[0022] Here, the term "dye" refers to chemical compounds that have the property of coloring other materials. Natural dyes are understood to be dyes of natural origin, such as plant, animal, or mineral sources, that themselves exhibit a color effect, even if this effect changes during the process. Color-active reagents are substances that react chemically with other substances during the process, for example, with substances contained in the aqueous solution of a natural tanning agent, thereby producing a color effect, such as becoming a dye or generating one.

[0023] Draining serves to prevent liquid not bound to the pipe mesh from being carried over to the next process step. The draining time can be short or long, or draining can be omitted entirely, without this having a significant impact on the dyeing process. ADVANTAGES

[0024] In step a), the reed mat becomes saturated with the acidic aqueous tannin solution. This solution quickly penetrates the rough, open-pored underside of each strand of the mat and rises through capillary action from the inside to the outer layer with its smooth surface. The strand swells slightly, expanding its pores and internal capillary channels, so that in step c), the natural dyes or color-active reagents can easily penetrate the strand and distribute themselves evenly. Capillary action and osmotic effects ensure that the dyes or color-active reagents penetrate deep into the plant structure of each strand of the reed mat from the rough underside, spread out, and rise to the smooth surface layer, even at the points where the strands of the mat overlap.Furthermore, chemical reactions of the dyes or color-effective reagents with the tannic acid already contained in the plant structure of the aqueous tannin solution can occur, causing a color change or even the formation of dyes in the first place.

[0025] Further preferred and advantageous features of the method according to the invention are the subject of dependent claims 2 to 13.

[0026] Preferably, the treatment of the pipe mesh with a natural dye or with color-active reagents in step c) is carried out by immersing the pipe mesh in the second immersion bath of an aqueous solution of a natural dye or color-active reagents and bathing the pipe mesh in this aqueous dyeing solution for the second predetermined period, followed by the subsequent steps; d) Removing the reed mesh from the second immersion bath and preferably allowing the remaining aqueous dye solution to drain off; e) Drying the reed mesh.

[0027] Here too, the draining step can be shorter or longer, or even omitted entirely. In drying step e), the water content of the aqueous solutions absorbed by the respective strand then evaporates, and the dyes remain stable within the plant structure.

[0028] Preferably, the aqueous tannin solution contains tannic acid as a natural tannin. The aqueous tannin solution preferably consists of tannin powder dissolved in tap water, according to a particularly preferred variant in a ratio of 25g to 50g of tannin powder to one liter of water.

[0029] The tanning solution is prepared in steps preceding step a). The dye solution is prepared in steps preceding step c).

[0030] In a first advantageous embodiment of the process, the dyeing solution contains iron or an iron compound.

[0031] It is advantageous if the iron-containing dye solution is produced by dissolving iron filings or steel wool in an acid, preferably acetic acid, and subsequently diluting it with water. According to a preferred embodiment of the process, commercially available steel wool is dissolved in 25% acetic acid to produce this dye solution, with a ratio of 3 g to 6 g of steel wool to 100 ml of the 25% acetic acid proving advantageous. Once the steel wool has dissolved in the acetic acid, this resulting concentrate of an iron-containing dye solution is preferably diluted with 10 times the amount of water.

[0032] Alternatively, the iron-containing dye solution can advantageously be produced by dissolving iron(II) sulfate in water, wherein, according to a preferred variant, such an iron-containing dye solution is formed by dissolving 2g of iron(II) sulfate in one liter of water.

[0033] According to a second advantageous embodiment of the process, the dyeing solution comprises at least one dye obtained from plants or plant components.

[0034] It is advantageous if the dyeing solution contains at least one natural dye obtained from the following plants or plant components: logwood, yellowwood, madder root, turmeric, walnut shells, birch leaves, mallow flowers.

[0035] It is advantageous if, in a step preceding process step c), the natural dye is obtained by elution with water from a natural dye carrier consisting of or formed from at least one plant or a plant component.

[0036] The tannin-soaked material is then placed in the second immersion bath. Applying heat is not strictly necessary. The material remains in the bath for 4 to 7 days. It should also be noted that plant dyes are difficult to control, as the intensity of the dye varies depending on the harvest.

[0037] Preferably, the step of eluting the dye is carried out at a water temperature in the range between 60 °C and 90 °C, preferably in the range between 70 °C and 80 °C, particularly preferably at temperatures around 70°C.

[0038] In a first handling variant of the method according to the invention, which can be combined with other embodiments, the pipe mesh is immersed in the immersion bath or baths in the form of a loosely rolled coil.

[0039] In an alternative second handling variant, which can also be combined with other embodiments, the pipe mesh is immersed in the immersion bath or baths in the form of mats.

[0040] Finally, in an alternative third handling variant, which can also be combined with other embodiments, the pipe mesh can be passed through the immersion baths in a transfer movement.

[0041] When immersing the reed mesh into the first immersion bath, it is preferably provided that the first specified period lasts at least as long as it takes for the reed mesh, saturated with the solution of the natural tannin, to sink to the bottom of the first immersion bath.

[0042] Advantageously, the first specified period is between two and eight days, preferably between four and seven days.

[0043] According to a particularly preferred embodiment of the process, which can be combined with other embodiments, it is provided that process step a) of bathing in the aqueous tanning agent solution in the first immersion bath is carried out at room temperature or below, wherein the aqueous tanning agent solution has a temperature between 0 °C and 30 °C, preferably between 5 °C and 20 °C, more preferably between 10 °C and 15 °C.

[0044] It is also particularly advantageous if the second specified period is between 15 and 20 hours.

[0045] Finally, according to a further preferred variant of the process, process step c) of dyeing is carried out at room temperature or a higher temperature, wherein the dyeing solution has a temperature between 10 °C and 90 °C, preferably between 15 °C and 60 °C, and more preferably between 20 °C and 30 °C.

[0046] According to an alternative embodiment of the inventive process, the treatment of the tubular mesh with a natural dye or with color-active reagents in step c) is carried out by exposing the tubular mesh, which was impregnated with tannin in step a), to ammonia vapors in a closed chamber for a third predetermined period. The vapors form brown salts together with the tannin in the tubular mesh.

[0047] A particularly preferred variant of the method according to the invention is one in which the first immersion bath is moved, at least temporarily, during the execution of step a). This movement can be continuous or discontinuous. The associated immersion bath vessel is preferably formed by a drum with a substantially horizontal drum axis, wherein the drum is moved about the drum axis. A discontinuous movement is preferred, in which the drum rotates by a predetermined angle with each rotation step and then remains in the new position until the next rotation step occurs. The stepwise rotation is very slow, for example, it cumulatively amounts to between 0.5 and 2 revolutions per minute, preferably 1 revolution per minute.The resulting agitation of the immersion bath prevents the immersion bath from separating, so that a uniform impregnation of all pipe braids of an inserted pipe braid stack or pipe braid roll (not shown) with an essentially homogeneous composition of the immersion bath liquid is achieved.

[0048] If the application of the natural dye or color-active reagents to the tubing according to claim 2 takes place in a second immersion bath, the second immersion bath can preferably also be moved, at least temporarily, during step c). This movement can also be continuous or discontinuous. The associated immersion bath vessel is preferably also formed by a drum with a substantially horizontal drum axis, wherein the drum is moved about the drum axis. Here, too, discontinuous movement is preferred, in which the drum rotates by a predetermined angle with each rotation step and then remains in the new position until the next rotation step occurs. The stepwise rotation is also very slow here and cumulatively amounts to, for example, between 0.5 and 2 revolutions per minute, preferably 1 revolution per minute.

[0049] A particularly preferred embodiment of the invention is one that can be combined with other embodiments and in which the tubular mesh is exposed to irradiation with ultraviolet light from at least one UV light source for a fourth predetermined period after the dyeing process according to claim 1 or claim 2. During this UV irradiation, the non-lightfast color components of the dye obtained in the dyeing process are broken down, and only the lightfast color components remain in the tubular mesh.

[0050] The invention is also directed to the use of a dyeing process, in particular a dyeing process according to the invention mentioned above, for braided reed mesh comprising the steps Immersion of the reed mesh in a first immersion bath of an aqueous solution of a natural tanning agent and bathing of the reed mesh in this aqueous tanning agent solution for a first predetermined period, at least until the reed mesh has absorbed the aqueous tanning agent solution and sinks to the bottom of the first immersion bath vessel and / or between one day and two weeks; removal of the material to be dyed from the first immersion bath and preferably allowing the remaining aqueous tanning agent solution to drain off; immersion of the reed mesh in a second immersion bath of an aqueous dyeing solution of a natural dye or color-active reagents and bathing of the reed mesh in the dyeing solution for a second predetermined period, at least until the reed mesh has absorbed the aqueous dyeing solution and sinks to the bottom of the second immersion bath;Removing the reed mat from the second immersion bath and preferably allowing the remaining aqueous dye solution to drain off; drying the reed mat, for dyeing already woven reed mats, in particular rattan or wicker mats, wherein the reed mat is formed by a plurality of flat strands obtained from the outer skin of a plant shoot and interwoven with one another, the smooth outer skin surface of which is oriented to one side, thus forming an upper smooth surface and a lower rough surface of the reed mat, wherein the second predetermined period until the reed mat has become saturated with the aqueous solution of the natural dye or the color-active reagents and sinks to the bottom of the second immersion vessel 3 lasts between 12 and 24 hours or from 4 to 7 days.

[0051] Alternatively, the invention also relates to the use of a dyeing process for braided reed netting comprising the steps Immersion of the reed mat in a first immersion bath of an aqueous solution of a natural tanning agent and bathing of the reed mat in this aqueous tanning agent solution for a first predetermined period, at least until the reed mat has absorbed the aqueous tanning agent solution and sinks to the bottom of the first immersion bath vessel and / or between one day and two weeks; removal of the material to be dyed from the first immersion bath and preferably allowing the still adhering aqueous tanning agent solution to drain off; exposure of the tannin-impregnated reed mat to ammonia vapors in a closed chamber. For dyeing already woven cane, in particular rattan or wickerwork, wherein the cane weaving is formed by a multitude of flat strands obtained from the outer skin of a plant shoot and interwoven together, the smooth outer skin surface of which is directed to one side, thus forming an upper smooth surface and a lower rough surface of the cane weaving.

[0052] Finally, the invention is also directed to a cane weave, in particular rattan or wicker weave, formed by a plurality of flat strands obtained from the outer skin of a plant shoot and interwoven together, the smooth outer skin surface of which is oriented to one side, thus forming an upper smooth surface and a lower rough surface of the cane weave, in particular a cane weave that has been treated as a finished cane weave according to a method according to the invention, wherein externally introduced dyes are present in the plant structure of the cane weave in a substantially uniform distribution up to the smooth outer skin surface. Such externally introduced dyes also include dyes that are formed in the plant structure only by coloring agents introduced externally into the plant structure.

[0053] It is advantageous if the even distribution of the dyes or color-active substances is also present in those areas of the reed mesh where individual strands of the reed mesh overlap each other.

[0054] The core of the invention thus relates to a two-stage dyeing process in which the material to be dyed, i.e., the reed matting, is first soaked in an aqueous solution of a natural tanning agent, i.e., a natural tannic acid solution. The tanning agents penetrate deep into the swollen reed matting and are deposited on the material to be dyed at a molecular level.

[0055] In a further step, the swollen reed mat is placed in a dye bath, an aqueous solution of a natural dye or color-active reagents, or it is exposed to a gas or vapor and left there. The dyes and / or color-active reagents penetrate the plant structure of the swollen fiber strands. If the aqueous dyeing solution, gas, or vapor contains dyes, these are incorporated into the plant structure and fixed there by the tannins. If the aqueous dyeing solution, gas, or vapor contains color-active reagents, these react with the incorporated tannins and produce a dye.

[0056] The inventors' experiments yielded the following results: tannin dye carrier color-active reagent resulting color tannin logwood beige-brown tannin Yellowwood yellowish-green tannin Madder root light brown-orange tannin turmeric light yellow tannin Walnut shells light grey-green tannin Birch leaves light grey-yellow tannin Mallow blossoms grey-green tannin iron brown-black

[0057] Potassium alum can also be used as a tanning agent instead of tannin.

[0058] Preferred embodiments of the invention with additional design details and further advantages are described and explained in more detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] It shows: Fig. 1 shows a section of a planar pipe mesh and Fig. 2 shows a simplified flow diagram of a method according to the invention. PRESENTATION OF PREFERRED EXECUTION EXAMPLES

[0060] Fig. 1Figure 1 shows a section of a cane weave 1, using a so-called Viennese cane weave as an example. Individual flat strands 10, 12, 14, 16, also known as rattan strands, which are each obtained from the outer skin of a plant shoot, for example, the rattan palm, are interwoven to form a cane weave. Horizontal strands 10, vertical strands 12, first oblique strands 14 running at a 45° angle to the vertical strands, and second oblique strands 16 running at a 45° angle to the vertical strands form the weave. At numerous overlap points, the strands lie above and below one another, such as the horizontal strand 10', which at the overlap point 11 lies below the vertical strand 12' and below the strand 14' running at an oblique angle in one direction, but crosses the strand 16 running at an oblique angle in a second direction.The weave of a Viennese wickerwork is generally known and is therefore not described further here. The invention is not limited to the Viennese wickerwork shown, but can be implemented in any weave made of plant strands.

[0061] Fig. 2 Figure 1 shows a simplified schematic representation of the process of the invention. First, in step a), a stack 13 of pre-woven reed braids 1 is immersed in a first immersion bath T1 containing an aqueous solution of a natural tanning agent and remains immersed in this first immersion bath T1 for a first predetermined period t1. Preferably, this continues until the reed braid is fully saturated with the aqueous solution of the natural tanning agent and sinks to the bottom of the first immersion bath vessel 2.

[0062] The first immersion vessel 2 is, for example, designed as a drum which – driven by a drive motor (not shown), preferably a stepper motor – rotates stepwise about a substantially horizontal drum axis A, with the drum remaining in its respective angular position between each rotation step. The second immersion vessel 3 can also be designed as a drum rotatable about a substantially horizontal axis of rotation, as described above.

[0063] After the first specified period t 1 has elapsed, the stack 13 of finished braided tube meshes 1 is removed from the first immersion bath vessel 2 and the liquid of the first immersion bath T1 adhering to the tube meshes 1 can drip off in step b).

[0064] Subsequently, in step c), the stack 13 of pre-woven tube braids 1 is immersed in a second immersion bath T2 containing an aqueous solution of a natural dye or color-active reagents and remains immersed in this second bath T2 for a second predetermined period t 2. Preferably, this also lasts until the tube braid is fully saturated with the aqueous solution of the natural dye or color-active reagents and sinks to the bottom of the second immersion vessel 3.

[0065] After the second specified period t 2 has elapsed, the stack 13 of finished braided tube meshes 1 is removed from the second immersion vessel 3 and the liquid of the second immersion bath T2 adhering to the tube meshes 1 can drip off in step d).

[0066] Then the stack 13 made from the finished braided reed meshes 1 is dried in step e).

[0067] Alternatively, instead of the second immersion bath T2, a closed container (not shown) can be provided into which the pipe mesh removed from the first immersion bath T1 is placed, preferably after most of the remaining adhering liquid has drained off, and where it is exposed to ammonia vapors for a predetermined third period t 3.

[0068] After the described dyeing process of the cane weave according to claim 1 or claim 2, the - preferably dried - cane weave is exposed in step f) to irradiation with ultraviolet light by a UV light source 4 for a fourth predetermined period t 4. This step f) can also be carried out at a later time, for example, when the dyed cane weave has already been processed and integrated into a piece of seating furniture.

[0069] Reference numerals in the claims, description and drawings serve only to improve understanding of the invention and are not intended to limit the scope of protection. Reference symbol list

[0070] It refers to: 1. Pipe mesh 2. First immersion vessel 3. Second immersion vessel 4. UV light source 10. Flat horizontal strand 10' flat horizontal strand 11. Overlap area 12. Flat vertical strand 12' flat vertical strand 13. Stack of finished woven pipe mesh 14. Flat first slanted strand 14' flat first slanted strand 16. Flat second slanted strand Arotation axis T1 first immersion bath T2 second immersion bath t1 first predetermined period t2 second predetermined period t3 third predetermined period t4 fourth predetermined period

Claims

1. A method for dyeing wickerwork with natural dyes or dye-effective reagents, wherein the wickerwork is formed by a plurality of intertwined flat strands obtained from the outer skin of a plant shoot whose smooth outer skin surface is directed towards one side, thus forming an upper smooth surface and a lower rough surface of the wickerwork, with the steps: a) immersing the wickerwork in a first immersion bath of an aqueous solution of a natural tanning agent and bathing the wickerwork in this aqueous tanning agent solution for a first predetermined period of time at least until the wickerwork has become saturated with the aqueous solution of the natural tanning agent and sinks to the bottom of the first immersion bath vessel and / or between one day and two weeks; b) removing the wickerwork from the first immersion bath; c) applying a natural dye or dye-effective reagents to the wickerwork for a second predetermined period of time between 12 hours and 24 hours or from 4 to 7 days or until the wickerwork is saturated with an aqueous solution of the natural dye or the dye-effective reagents in a second immersion bath vessel and sinks to the bottom of the second immersion bath vessel.

2. The method according to claim 1, characterised in that the application of a natural dye or dye-effective reagents to the wickerwork in step c) is carried out by immersing the wickerwork in the second immersion bath containing an aqueous solution of a natural dye or dye-effective reagents and bathing the wickerwork in this aqueous dyeing solution for the second predetermined period of time, and in that thereafter the following steps will follow; d) removing the wickerwork from the second immersion bath and preferably allowing the aqueous dye solution still adhering to it to drain off; e) drying the wickerwork.

3. The method according to one of the preceding claims, characterised in that the wickerwork is immersed in the immersion bath or immersion baths in the form of a loosely rolled coil.

4. The method according to claim 1 or 2, characterised in that that the wickerwork is immersed in the immersion bath or immersion baths in the form of mats.

5. Method according to one of the preceding claims, characterised in that that the first predetermined period of time lasts at least until the wickerwork, which is saturated with the solution of the natural tanning agent, sinks to the bottom of the first immersion bath.

6. The method according to one of the preceding claims, characterised in that that the first predetermined period of time is between two days and eight days, preferably between four and seven days.

7. The method according to one of the preceding claims, characterised in that the method step a) of bathing in the aqueous tanning agent solution in the first immersion bath is carried out at room temperature or below, wherein the aqueous tanning agent solution has a temperature between 0 °C and 30 °C, preferably between 5 °C and 20 °C, more preferably between 10 °C and 15 °C.

8. The method according to one of the preceding claims, characterised in that the second predetermined period of time is between 15 hours and 20 hours.

9. The method according to one of the preceding claims, characterised in that the method step c) of dyeing is carried out at room temperature or at a higher temperature, wherein the dyeing solution has a temperature between 10 °C and 90 °C, preferably between 15 °C and 60 °C, more preferably between 20 °C and 30 °C.

10. The method according to claim 1, characterised in that the application of a natural dye or color-active reagents to the wickerwork in step c) is carried out by exposing the wickerwork soaked with tannin in step a) to ammonia vapors in a closed chamber for a third predetermined period of time (t3).

11. The method according to one of the preceding claims, characterised in that the first immersion bath (T1) is agitated at least temporarily during the execution of step a).

12. The method according to one of claims 2 to 11, characterised in that the second immersion bath (T2) is agitated at least temporarily during the execution of step c).

13. The method according to one of the preceding claims, characterised in that after the dyeing process according to claim 1 or according to claim 2, the wickerwork is exposed in a step f) for a fourth predetermined period of time (t4) to irradiation with ultraviolet light from at least one UV light source (4).

14. Use of a dyeing method for braided wickerwork comprising the steps of - immersing the wickerwork in a first immersion bath consisting of an aqueous solution of a natural tanning agent and bathing the wickerwork in this aqueous tanning agent solution for a first predetermined period of time at least until the wickerwork has become completely saturated with the aqueous solution of the natural tanning agent and sinks to the bottom of the first immersion bath vessel (2) and / or between one day and two weeks; - removing the dyed material from the first immersion bath; - immersing the wickerwork in a second immersion bath containing an aqueous dye solution of a natural dyeing substance or dye-effective reagents and bathing the wickerwork in the dye solution for a second predetermined period of time at least until the wickerwork has become saturated with the aqueous dye solution and sinks to the bottom of the second immersion bath; - removing the wickerwork from the second immersion bath; - drying the wickerwork, for dyeing already braided wickerwork, in particular rattan or peddig wickerwork, wherein the wickerwork is formed by a plurality of flat strands obtained from the outer skin of a plant shoot and intertwined with each other, the smooth outer skin surface of which is directed towards one side, thus forming an upper smooth surface and a lower rough surface of the wickerwork, wherein the second predetermined period of time lasts until the wickerwork is soaked with the aqueous solution of the natural dye or the dye-effective reagents and sinks to the bottom of the second immersion bath vessel (3) or between 12 hours and 24 hours or from 4 to 7 days.

15. Use of a dyeing method for braided wickerwork comprising the steps of - immersing the wickerwork in a first immersion bath consisting of an aqueous solution of a natural tanning agent and bathing the wickerwork in this aqueous tanning agent solution for a first predetermined period of time at least until the wickerwork is soaked with the aqueous tanning agent solution and sinks to the bottom of the first immersion bath vessel (2) and / or between one day and two weeks; - removing the dyed material from the first immersion bath; - exposing the wickerwork soaked with tannin in a closed chamber to ammonia vapours, for dyeing already braided wickerwork, wherein the wickerwork is formed by a plurality of flat strands obtained from the outer skin of a plant shoot and intertwined with each other, the smooth outer skin surface of which is directed towards one side, thus forming an upper smooth surface and a lower rough surface of the wickerwork,16. A wickerwork (1), in particular rattan or peddig wickerwork, formed by a plurality of flat strands (10, 12, 14, 16) obtained from the outer skin of a plant shoot and intertwined with one another, the smooth outer skin surface of which strands is directed towards one side, thus forming an upper smooth surface and a lower rough surface of the wickerwork (1), in particular wickerwork (1) which has been treated as finished wickerwork (1) according to a method according to claims 1 to 13, characterised in that dyes introduced externally into the plant structure of the wickerwork (1) are distributed substantially uniformly up to the smooth outer skin surface.

17. A wickerwork according to claim 16, characterised in that the uniform distribution of the dyes or dye-effective substances is also present in those areas (11) of the wickerwork (1) in which individual strands (10', 12', 14') of the wickerwork (1) overlap each other.

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