Natural leather substitute based on banana pseudostem fibers and method of preparation thereof

Abstract

The present invention relates to a natural leather substitute derived from banana pseudostem fibers and a method for its preparation. The method comprises extracting fibers from banana pseudostem, followed by cleaning to remove components that affect fiber cohesion. The cleaned fibers are then dried to a controlled moisture content and ground into a fine powder. A saline treatment is applied to modify fiber properties, enhancing binding characteristics. The treated fibers are then coated with a binder and finishing material on a release sheet to form a structured composite layer. The coated material undergoes a curing process at controlled conditions to achieve the desired texture and mechanical strength. The resultant natural leather substitute exhibits enhanced durability, flexibility, and water resistance compared to conventional alternatives, making it suitable for various commercial applications. The method offers a sustainable, eco-friendly alternative to animal-derived leather and synthetic substitutes while utilizing an agricultural byproduct.

Description

[0001] NATURAL LEATHER SUBSTITUTE BASED ON BANANA PSEUDOSTEM FIBERS AND METHOD OF PREPARATION THEREOF FIELD OF THE INVENTION

[0002] The present invention, in general, relates to a natural leather substitute and method of preparation thereof, and, more particularly, to a natural leather substitute prepared from organic products preferably fibres from banana pseudostem and a novel method of producing the natural leather substitute.

[0003] BACKGROUND OF THE INVENTION

[0004] Leather production has long been associated with various environmental and ethical concerns, including deforestation, excessive water consumption, and an emission of plurality of hazardous chemicals from tanning processes. The conventional leather industry heavily relies on animal hides, leading to significant ecological consequences such as land degradation, greenhouse gas emissions, and extensive water pollution. Additionally, synthetic leather alternatives are typically derived from petroleum-based polymers, which contribute to non-biodegradable waste accumulation and environmental toxicity.

[0005] With the increasing global emphasis on sustainability, numerous research efforts have been directed towards the development of alternative materials that replicate the mechanical properties and aesthetics of natural leather while minimizing environmental impact. One such alternative involves a use of plant-based fibers, particularly those extracted from agricultural by-products. Various fibers, including pineapple leaf fibers, coconut coir, and hemp, have been explored for their potential in producing leather-like materials. However, many of these materials require extensive chemical treatments or synthetic binders to achieve desired durability and texture, thereby undermining their ecological benefits.

[0006] WO2021121509A2 a method for producing a hydrophobic non-woven textile using fruit or vegetable pomace, which consists of residual skins, seeds, and pulp. A key limitation of this approach is the choice of raw material, as pomace lacks the structural integrity of stem fibers. Unlike pseudostem fibers, which are inherently fibrous and strong,pomace must be mechanically refined into disrupted fibers, leading to a loss of natural fiber length and strength. Further, the method involves milling or refining the pomace into disrupted fibers with a maximum length of 2.0 mm, that compromises mechanical strength and durability of final product of this disclosure. Furthermore, the disclosure relies on comminution (milling / refining) of the pomace, followed by the addition of density-modifying agents ranging from 10% to 85% (w / w). This dependency on chemical modifications alters a texture and compromises the fiber purity. The dehydration process in the disclosure involves centrifugation, filtration, pressing, and heating, which leads to inconsistencies in fiber composition and its mechanical properties.

[0007] Additionally, the prior art relies on hydrophobic polymer coatings to enhance the water resistance of the textile. The hydrophobic polymer coating process involves forming a single-layer non-woven textile, which is then coated with a polymer to achieve hydrophobicity. A moisture content of the prior art textile remains high which leads to degradation, microbial growth, and reduced lifespan.

[0008] Banana pseudostem, which is a by-product of banana cultivation, presents a promising source of fibers for sustainable material production. The pseudostem, being an abundant and renewable resource, is traditionally discarded as agricultural waste. The fibers extracted from banana pseudostem possess unique structural characteristics, including high tensile strength and flexibility, making them suitable for fabricating composite materials. The development of a method to convert these fibers into a leather substitute would not only offer a viable eco-friendly alternative but also contribute to waste valorisation.

[0009] The present invention addresses the aforementioned concerns by providing a method for preparing a leather-like material from banana pseudostem fibers through a series of extraction, cleaning, drying, grinding, saline treatment, coating, and heating steps. The resulting material offers comparable properties to conventional leather while maintaining sustainability and biodegradability.

[0010] OBJECTIVE OF THE INVENTION

[0011] The objective of the present invention is to provide a natural leather substitute derived from banana pseudostem fibers and a method for its preparation that overcomesthe limitations of existing synthetic and plant-based alternatives. The present invention aims to develop a durable, flexible, and eco-friendly material with improved mechanical properties comparable to natural leather while utilizing sustainable raw materials.

[0012] A key objective is to ensure that the fibrous integrity of banana pseudostem is preserved, enabling the formation of a strong, cohesive structure without excessive chemical modification. The method is structured to achieve a controlled moisture content, improving the durability, resistance to degradation, and longevity of a final product.

[0013] Additionally, the present invention seeks to create a multi-layered material with enhanced strength, flexibility, and texture, eliminating the need for synthetic hydrophobic coatings. By integrating biodegradable binders and finishing layers, the present invention provides an environmentally responsible alternative to conventional leather, suitable for applications in fashion, upholstery, accessories, and industrial use.

[0014] BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The accompanying figures illustrate several embodiments of the disclosure and, together with the description, serve to explain the principles of the disclosure. One of ordinary skill in the art readily recognizes that the embodiments illustrated in the figures are merely exemplary, and are not intended to limit the scope of the present disclosure.

[0016] FIG. 1 illustrates an exemplary flow diagram of a method of preparing natural leather substitute according to an embodiment of the present invention.

[0017] It may be noted by those skilled in the art that the diagrams, schematics, illustrations, and similar representations provided are conceptual views or processes demonstrating systems and methods embodying the present invention. The functionalities of the various elements depicted may be implemented using dedicated hardware or hardware that can run corresponding software. Similarly, any switches shown in the figures are conceptual and their functions might be achieved through program logic, dedicated logic, a combination of program control and dedicated logic, or manual operation, depending on the choice of the entity implementing the present invention. Additionally, it is recognized that the described hardware, software, processes, methods, and / or operating systems are illustrative and not restricted to any specific named examples.Further areas of applicability of the present disclosure will become apparent from the complete description provided hereinafter.

[0018] It should be understood that the complete description of exemplary embodiments is intended for illustration purposes only and is, therefore, not intended to necessarily limit the scope of the present disclosure.

[0019] DETAILED DESCRIPTION

[0020] The present disclosure is more particularly described in the following examples that are intended as illustrative only since numerous modifications and variations therein will be apparent to those skilled in the art. Various embodiments of the present disclosure are now described in detail. Referring to the drawings, like numbers, if any, indicate like components throughout the views. As used in the description herein and throughout the claims that follow, the meaning of "a", "an", and "the" includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein and throughout the claims that follow, the meaning of "in" includes "in" and "on" unless the context clearly dictates otherwise. Moreover, titles or subtitles may be used in the specification for the convenience of a reader, which shall have no influence on the scope of the present disclosure.

[0021] Additionally, some terms used in this specification are more specifically defined below.

[0022] The terms used in this specification generally have their ordinary meanings in the art, within the context of the present disclosure, and in the specific context where each term is used. Certain terms that are used to describe the present disclosure are discussed below, or elsewhere in the specification, to provide additional guidance to the practitioner regarding the description of the disclosure. For convenience, certain terms may be highlighted, for example using italics and / or quotation marks. The use of highlighting has no influence on the scope and meaning of a term; the scope and meaning of a term are the same, in the same context, whether or not it is highlighted. It will be appreciated that the same thing may be said in more than one way. Consequently, alternative language and synonyms may be used for any one or more of the terms discussed herein, nor is any special significance to be placed upon whether or not a term is elaborated or discussedherein. Synonyms for certain terms are provided. A recital of one or more synonyms does not exclude the use of other synonyms. The use of examples anywhere in this specification including examples of any terms discussed herein is illustrative only, and in no way limits the scope and meaning of the disclosure or of any exemplified term. Likewise, the disclosure is not limited to various embodiments given in this specification.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. In the case of conflict, the present document, including definitions will control.

[0024] As used herein, "around", "about" or "approximately" shall generally mean within 20 percent, preferably within 10 percent, and more preferably within 5 percent of a given value or range. Numerical quantities given herein are approximate, meaning that the term "around", "about" or "approximately" may be inferred if not expressly stated.

[0025] As used herein, "plurality" means two or more.

[0026] As used herein, the terms "comprising," "including," "carrying," "having," "containing," "involving," and the like are to be understood to be open-ended, i.e., to mean including but not limited to.

[0027] As used herein, the phrase at least one of A, B, and C should be construed to mean a logical (A or B or C), using a non-exclusive logical OR. It should be understood that one or more steps within a method may be executed in a different order (or concurrently) without altering the principles of the present disclosure.

[0028] The utilization of banana fibers as a substrate for various applications is backed by its commendable physical and chemical properties, which render it a high-quality fiber material. When examining its physical attributes, banana fibers boast excellent characteristics such as a favourable modulus of elasticity, impressive tensile strength, and notable stiffness. These qualities make banana fibers particularly well-suited for serving as a substrate in leather production. Additionally, banana fibers exhibit a remarkable strength and demonstrate lower strain at break, enhancing their suitability for use in various applications, including leather production. Furthermore, the inherent shiny appearance of banana fibers further enhances their appeal as a substrate material for leather production.Based on a large number of qualities of banana fibers, the present specification provides a method for preparing a natural leather substitute from banana pseudostem fibers and a resulting material of the method. The method comprises extracting fibers, subjecting the extracted fibers to a cleaning process, followed by drying, grinding, saline treatment, coating with binders, and curing to achieve a final structure of the natural leather substitute material. The process of the present invention ensures a formation of a flexible, durable, and environmentally friendly material with characteristics comparable to conventional natural leather.

[0029] BANANA PSEUDOSTEM

[0030] The banana pseudostem is a byproduct of banana cultivation, typically discarded after fruit harvesting. It is a thick stalk grows up from the ground and form the backbone of the herbaceous plant. It is a fibrous part of banana tree that comprises a cylindrical structure consisting of a plurality of layers of leaf sheaths. The pseudostem fibers are rich in cellulose, hemicellulose, and lignin, making them suitable for use in composite materials.

[0031] The banana pseudostem used in the present method is procured from commercial sources, as it is widely available as an agricultural by-product and is traded as a commodity in various markets (local and online). The banana pseudostem, which remains after a harvesting of bananas, is commonly utilized for multiple industrial applications and is readily obtainable without any restriction on its commercial use. Therefore, the raw material (Banana pseudostem) of the present invention is procured as a commodity from market sources rather than being sourced directly from nature or cultivated specifically for the invention. The procurement process provides a consistent and sustainable supply of raw material for fiber extraction while complying with the applicable legal framework governing a use of biological resources in India.

[0032] The method of the present invention begins with an extraction of fibers from the procured banana pseudostem. The banana pseudostem, which is a byproduct of banana cultivation, comprises long and fibrous strands that serve as a primary raw material of the present invention. Fiber extraction can be performed using one or more mechanical, manual, or enzymatic processes. In an embodiment following a mechanical process forfiber extraction, one or more decortication machines or fiber-extracting rollers may be used to separate a fibrous material in the banana pseudostem from the non-fibrous matrix. In another embodiment following a manual process for fiber extraction, the fibers may be peeled and stripped from the pseudostem using hand tools.

[0033] Following extraction, the raw fibers contain various natural impurities, including organic and inorganic components, which need to be removed or reduced to enhance fiber quality and ensure compatibility with subsequent processing steps. Therefore, once extracted, the fibers undergo a cleaning process to eliminate one or more components that can negatively impact fiber cohesion and binding during material formation. This step enhances an ability of the fibers to bond with binders, improving a durability and performance of the final leather substitute produced through this inventive method.

[0034] The cleaning process may comprise a plurality of techniques, including but not limited to washing, chemical treatment, and enzymatic hydrolysis, depending on a degree of purification required. The one or more components removed by the cleaning process may comprise organic components such as pectin, lignin, polysaccharides (cellulose and hemicelluloses), water-soluble materials, saturated and unsaturated fats, as well as inorganic components like metallic compounds, non-metallic compounds, and / or ash.

[0035] In an embodiment, water-soluble materials may be selectively reduced through an aqueous washing process. The extracted fibers may be subjected to a controlled soaking step in a deionized or mildly acidic water to remove excess soluble sugars, minerals, and other hydrophilic compounds. Such a removal of water-soluble materials may ensure that the fibers do not retain excessive moisture-attracting elements, which could otherwise impact a stability of the final material. The washing step may be optimized to achieve an appropriate balance between impurity removal and fiber retention, preserving the essential mechanical properties required for further processing.

[0036] In another embodiment, one or more from pectin, lignin, or polysaccharides (cellulose and hemicelluloses), may be removed using an alkaline treatment, wherein the fibers may be soaked in a dilute sodium hydroxide (NaOH) solution for a predetermined duration to break down the components, which act as a binding agent in plant structures, making it easier to wash away. In another embodiment, oxidative treatment of one or more of these organic components using hydrogen peroxide (H2O2) can be employed,which degrades the organic components without significantly affecting cellulose content. A degree of removal may be controlled to maintain a structural integrity of the fibers while ensuring an optimal bonding with the binder in later stages.

[0037] Further, in yet another embodiment, certain metallic and non-metallic compounds naturally present in the fibers may be minimized through a mild acid treatment. A diluted organic acid solution, such as but not limited to citric acid or acetic acid, may be used to dissolve and remove the unwanted mineral components without causing a degradation to the fibrous structure. This process may enhance a uniformity of the fibers and improve their compatibility with the binder system, leading to a more consistent final product.

[0038] Additionally, saturated and unsaturated fats, which may be present in trace amounts within the fiber matrix, may be reduced using a mild solvent extraction method. The fibers may be exposed to an ethanol or isopropanol-based solution, which selectively dissolves lipid-based compounds without compromising an overall integrity of the fibers. By reducing the fatty components, the treated fibers achieve improved adhesion properties and a more uniform texture in the final natural leather substitute.

[0039] Following cleaning step, the fibers are dried to a desired moisture content to prevent degradation and improve their compatibility with subsequent processing steps. The drying process may involve air drying, sun drying, or oven drying depending on one or more environmental conditions and production requirements. A moisture content is typically reduced to a predetermined controlled range to ensure ease of grinding and uniformity in the final product.

[0040] After drying, a moisture content of the fibers may be controlled within a range of 5% to 15%, ensuring an optimal balance between flexibility and structural integrity. Maintaining moisture below 15% prevents microbial growth and degradation while ensuring proper adhesion to the binder during the coating process. Conversely, reducing moisture below 5% may lead to excessive brittleness, making the fibers prone to breakage during subsequent processing. The drying step may be performed using air drying, sun drying, or controlled oven drying, with drying conditions adjusted to achieve a desired moisture level. A precise control of moisture content within the predetermined range enhances a mechanical performance and durability of the final natural leather substitute.After drying, the fibers are ground into a fine powdered form to facilitate uniform dispersion and coating during an upcoming binder application stage of the present invention. Grinding may be performed using mechanical grinders, milling machines, or pulverisers, ensuring that a fiber size is reduced to a level suitable for forming a homogeneous material. A particle size of the ground fibers may vary depending on an intended texture and / or one or more physical or mechanical properties of the final leather substitute.

[0041] The powdered fibers undergo a saline treatment, which enhances their binding properties and improves a stability of the final material. In this process, the fibers may be soaked in a saline solution for a predetermined period, allowing the salt ions to interact with the fiber structure. This treatment aids in fiber dispersion, prevents clumping, and enhances adhesion between the fibers and the binder.

[0042] Following the saline treatment, the fibers are coated with a binder to form a cohesive layer. The binder may be a single compound or a mixture of two or more compounds, selected from polyvinyl chloride (PVC), plasticizers such as Kanatol, chemical stabilizers, Bentazone, polyethylene, polyurethane, acrylic polymers, dyes, pigments, sodium salts, potassium salts, bio-based polyurethane (PU) adhesive, natural rubber, corn starch, natural adhesives, cork dust, walnut dust, and coconut dust. A selection of the binder can be determined based on a desired flexibility, durability, and an appearance of the final leather substitute.

[0043] The coated fibers are applied onto a release sheet, such as but not limited to a silicone-coated sheet, which facilitates the formation of a uniform material. In an embodiment, a finishing layer may also be applied comprising pigments, dyes, or protective coatings to achieve a desired aesthetic and functional properties.

[0044] The coated layers undergo a controlled heating process at a predetermined temperature to cure and set the material. Heating ensures proper bonding between the fibers and the binder while enhancing one or more mechanical properties of the leather substitute. The temperature and duration of heating may be optimized to achieve the desired flexibility, strength, and texture.In some embodiments, the coated fibers may also be pressed to achieve a specific thickness and surface texture, mimicking the feel of natural leather. This step may further refine the final material, making it suitable for a plurality of applications.

[0045] While heating at a predetermined temperature can be employed to enhance adhesion and finalize the structural properties of the material, some embodiment may comprise keeping the coated material at room temperature for a predetermined duration of time, for example but not limited to 24-72 hours. This controlled curing period allows the binder to set gradually, ensuring a uniform adhesion without excessive thermal exposure. A choice between heating and room-temperature curing may depend on a specific binder formulation and / or desired mechanical characteristics, providing flexibility in the manufacturing process while maintaining the integrity and durability of the natural leather substitute.

[0046] Further, the release sheet used in the present invention serves as a temporary substrate during the coating and curing stages, ensuring that the binder and fiber matrix achieve a desired structural integrity and surface finish before being separated from the sheet. For this purpose, a plurality of types of release sheets may be used, depending on a required texture, one or more adhesion properties, and / or processing conditions.

[0047] In an embodiment, a silicone-coated paper may be used as a release sheet providing a non-stick surface that allows for easy separation of a formed natural leather substitute after the curing process. The silicone coating on the release sheet may ensure that the binder does not adhere permanently to the release sheet while also offering a smooth and uniform texture to the final product. A thickness and flexibility of the silicone-coated paper based release sheet may be varied to optimize processing efficiency while maintaining cost-effectiveness.

[0048] In another embodiment, polymer-based release films such as polyethylene (PE) or polypropylene (PP) films can be used. These films offer excellent non-stick properties and can withstand elevated temperatures during the heating stage. A use of polymer-based release sheets may be advantageous when a glossy or uniform finish is desired on the final product. Further, such sheets may be reused multiple times, making them a more sustainable option in large-scale production.In another embodiment, a suitable release sheet option is polytetrafluoroethylene (PTFE)-coated fabric, that provides superior heat resistance and durability. PTFE-coated sheets may be useful in processes involving prolonged exposure to heat and pressure, ensuring that the binder and fiber composite does not adhere to the surface. These sheets may be beneficial for achieving a high-performance finish while maintaining a structural integrity of the final material.

[0049] In some embodiments, metal release sheets such as but not limited to stainless steel or aluminum plates with a non-stick surface coating can also be employed. These sheets may provide excellent dimensional stability and allow for uniform pressure distribution during the curing process. The use of metal sheets may be beneficial when a specific texture or embossed pattern is required in the final product, as the surface characteristics of the metal can be transferred onto the natural leather substitute.

[0050] Depending on the intended application and the desired characteristics of the final material, a selection of a suitable release sheet may be optimized to ensure ease of processing, efficient separation, and high-quality surface properties.

[0051] The natural leather substitute produced from banana pseudostem fibers in the present invention demonstrates superior mechanical properties compared to conventional natural leather substitutes and existing vegan leather materials, particularly in terms of tensile strength, tear resistance, flexibility, and durability. Many existing vegan leather materials rely on fruit or vegetable pomace, synthetic polymers, or composite materials that often lack the structural integrity and mechanical performance required for long-term use. In contrast, the present invention benefits from the high-strength fibrous composition of banana pseudostem, which undergoes selective treatment to remove undesirable components while preserving essential structural elements that contribute to superior mechanical strength.

[0052] One of the significant improvements is in tensile strength, where the present invention outperforms conventional natural leather substitutes due to the interwoven network of treated banana fibers, which provide a strong yet flexible structure. Many existing vegan leather materials rely on short fibers, binding agents, or synthetic reinforcements that weaken over time or under stress. The controlled binder application in the present invention ensures that the fibers retain their mechanical strength, makingthe material suitable for high-stress applications such as but not limited to footwear, upholstery, bags, jackets, and other accessories.

[0053] Further, the tear resistance of the present invention is notably an enhancement compared to existing vegan leather materials. Materials that use pomace-derived fibers or synthetic fillers often suffer from limited structural integrity, leading to higher susceptibility to tearing, particularly in applications requiring prolonged use and mechanical stress. The banana pseudostem based material of the present invention, by contrast, maintains fiber integrity through its optimized cleaning, drying, and binding processes, resulting in a more robust material that can endure repeated stress without failure.

[0054] In terms of flexibility and elongation, the present invention provides a balanced combination of pliability and strength, unlike many existing leather substitutes that may be brittle due to excessive binder content or lack of fiber reinforcement. A selective removal of certain fiber components, such as but not limited to inorganic materials, water soluble materials, lignin, and / or pectin, without excessive degradation of cellulose and hemicellulose, ensures that the material retains an optimal level of flexibility to prevent cracking or stiffness over time, which is a common drawback in existing synthetic or plantbased non-woven materials.

[0055] Furthermore, the abrasion resistance of the present invention is superior, as the fiber-binder composite is formulated to withstand wear and tear more effectively than many conventional vegan leather materials, which often suffer from surface degradation. A structured layering of the banana fiber-based material, along with a carefully selected finishing layer, prevents rapid wear and maintains surface integrity over prolonged usage. This makes the present invention particularly well-suited for applications requiring frequent handling and movement.

[0056] Moreover, the moisture resistance of the present invention is an improvement over many existing natural leather substitutes that rely on pomace fibers, which have a higher tendency to absorb water and lose their mechanical strength. The controlled fiber processing in the present invention ensures that the final material retains a balanced moisture absorption profile, preventing excessive swelling or weakening when exposed tohumidity or liquids. Additional surface treatments can further enhance water repellency, ensuring that the material remains durable in various environmental conditions.

[0057] Therefore, the banana pseudostem fiber-based natural leather substitute presents a significant advancement over conventional natural leather substitutes by offering a stronger, more flexible, and more durable alternative that better mimics the mechanical properties of natural leather. The innovative processing steps and fiber treatment methods contribute to a final material that is well-suited for demanding applications, ensuring longevity and performance superiority over many plant-based or synthetic leather alternatives.

[0058] Based on above description of the present invention, the following steps may be taken in an embodiment for preparing the natural leather substitute material from banana pseudostem fibers:

[0059] STEP A) EXTRACTING FIBERS FROM BANANA PSEUDOSTEM:

[0060] In order to extract fibers from a banana pseudostem, firstly the pseudostem is cut into manageable pieces of a desired length. The desired length may range from 10 cm to 5 meters based on the size of the banana pseudostem or a preference of an operator extracting the fibers.

[0061] In an embodiment, a mechanical decortication method may be employed to separate fibers from the banana pseudostem or stem pieces. The mechanical decortication process may involve passing the banana pseudostem or stem pieces through a decorticating machine that is configured to scrape away a non-fibrous material portion of the banana pseudostem or stem pieces and leave behind a fibrous bundles of banana fibers. The separated fibers are collected and prepared for further processing.

[0062] In another embodiment, the mechanical decortication may involve using one or more rotating blades or one or more rollers that may physically break down the pseudostem structure while minimizing a damage to the banana fibers and effectively removing non-fibrous material portion of the banana pseudostem or stem pieces. A quality of the extracted fibers is crucial, as it impacts the final product's properties. Therefore, the fibers extraction step may further comprise means and methods forcontrolling one or more decortication parameters, such as blade sharpness, speed, or pressure.

[0063] Further, in another embodiment, the banana pseudostem or stem pieces may undergo a preliminary soaking step to soften the fibers and facilitate an easier extraction. The soaking may be done in water or a mild chemical solution, which may break down the lignin and hemicellulose, and further aiding the separation of fibers. The extracted fibers may then rinsed to remove any residual chemicals or plant sap, ensuring they are ready for the cleaning stage.

[0064] Further, in another embodiment, the banana pseudostem or stem pieces may be rolled lightly to remove the excess moisture before feeding for extraction step. This step may be used to remove impurities in the rolled fibres such as pigments, broken fibres, coating of cellulose etc.

[0065] In another embodiment, a manual extraction process may be employed to separate fibers from the banana pseudostem or stem pieces. The manual extraction process may involve fastening the banana pseudostem or stem pieces on a platform or a frame and manually extracting the fibers using a comb alike tool.

[0066] However, in another embodiment, the fiber extraction may be performed by hand scraping, chemically, by retting, or using one or more raspadors tools.

[0067] STEP B) CLEANING THE EXTRACTED FIBERS:

[0068] The extracted fibers often contain impurities such as dirt, residual plant matter, and other contaminants. Cleaning is essential to ensure the quality of the final product. In an embodiment, the extracted fibers may be washed with clean water to remove impurities contained in the extracted fibers. In another embodiment, a mild detergent may be used for an enhancement in the cleaning process.

[0069] In an embodiment, the extracted fibers may be soaked in water for a predetermined duration of time to allow the impurities to loosen and be washed away. In a further embodiment, after soaking, the soaked fibers may be thoroughly rinsed to ensure removal of all contaminants or impurities. The cleaning process not only enhances the purity of the fibers but also improves their bonding properties in subsequent steps.In another embodiment, a chemical cleaning may be employed to remove one or more organic / non-organic components of the extracted fibers. The one or more organic / non-organic components of the extracted fibers may be selected from a group of polysaccharides, cellulose, hemicelluloses, lignin, pectin, water soluble material, saturated fat, unsaturated fat, one or more metallic / non-metallic compounds in the extracted fibers, or ash.

[0070] The cleaning may be done manually or using an automated washing system, depending on a scale of production or a desire of a cleaner performing the cleaning process. Further, manual cleaning may involve agitating the fibers soaked in water by hand to ensure that each of the fiber bundle is adequately cleaned.

[0071] In another embodiment, one or more automated washing systems may be employed for mechanical agitation or ultrasonic waves to achieve similar but more efficient cleaning results.

[0072] Further, in another embodiment, a series of multiple cleaning methods may be employed to efficient cleaning of the extracted fibers.

[0073] Further, an effectiveness of the cleaning process may be evaluated by analysing the water used for rinsing. Clear water indicates the removal of most impurities, while murky water suggests that further cleaning may be necessary. The cleaned fibers are then subjected to a final rinse with clean water to ensure all detergents and / or residual contaminants are removed.

[0074] Proper cleaning is crucial as any remaining impurities can interfere with an ability of extracted fibers to bond with binders and form a cohesive material. Further, remained impurities may affect the aesthetic properties of the final product, leading to discoloration or uneven texture, or short lifespan. Therefore, the cleaning process must be thorough and consistent to ensure high-quality fibers for subsequent processing steps.

[0075] STEP C) DRYING THE CLEANED FIBERS:

[0076] Once cleaned, the fibers must be dried to reduce their moisture content. Drying may be achieved through air drying, sun drying, or oven drying. Air drying involves spreading the fibers in a well-ventilated area, allowing them to dry naturally over time.This method is energy-efficient and environmentally friendly but may take long time to dry the cleaned fibers.

[0077] Sun drying involves spreading the fibers in a well-ventilated area that receives a significant amount direct / indirect sunlight, allowing the fibers to dry naturally over time. This method is energy-efficient and environmentally friendly but may take long time to dry the cleaned fibers. However, it is faster drying method than air drying.

[0078] Oven drying, on the other hand, comprises placing the cleaned fibers in an electrical or thermal oven at a controlled temperature. This method ensures uniform drying and significantly reduces drying time.

[0079] Oven drying is faster and provides more control over the drying conditions. The fibers may be placed in an oven set to a temperature range of 60-90°C. Higher temperatures may be used with care to avoid overheating that may damage the fibers. A drying duration in an oven may depend on a moisture content of the fibers.

[0080] In an embodiment, the cleaned fibers may be dried until they reach a moisture content of approximately 10-12%, which is optimal for the grinding process. A proper drying is crucial to prevent mold growth and ensure the structural integrity of fibers.

[0081] Further, a moisture content of the fibers being drying may be monitored throughout the drying process using any suitable machines, devices, or tools for moisture monitoring. The monitoring may be done using dedicated moisture meters or by weighing the fibers at regular intervals. Once a desired moisture content is achieved, the fibers may be removed from the drying area or oven, and allowed to cool to room temperature.

[0082] Further, in another embodiment, the cleaned fibers may be sliced into thin strands before drying. In another embodiment, the dried fibers may be sliced into thin strands after drying.

[0083] In an embodiment, during drying, the fibers may be spread out in thin layers on drying racks or mats. The drying area may be well-ventilated to facilitate the evaporation of moisture. Air drying may take few to several days, depending on the ambient temperature and humidity. Further, a regular turning of the fibers helps to ensure an even drying and prevent the growth of mold or mildew in the final product i.e., banana leather.

[0084] Properly dried fibers are essential for the grinding process. Excess moisture content in the dried fibers may cause the fibers to clump together, making grinding difficultand resulting in uneven particle sizes. Over-drying, on the other hand, can make the fibers brittle and prone to breaking during grinding. Therefore, achieving the optimal moisture content is critical for the subsequent steps in the process.

[0085] STEP D) GRINDING THE DRIED FIBERS INTO A POWDERED FORM:

[0086] The dried fibers are then ground into a fine powder using a mechanical grinder. The grinding process reduces the dried fibers to a powdered form, which enhances their ability to blend with binders and form a cohesive material. A particle size of the powdered fibers may be controlled by adjusting the grinder settings.

[0087] Further, in an embodiment, the ground fibers may be collected and passed through a sieve to ensure a uniform particle size distribution. The powdered form of the fibers increases their surface area, facilitates better interaction with a saline solution and binding agents in subsequent steps. This step is critical for achieving a smooth and homogeneous final product i.e., banana leather.

[0088] Mechanical grinding may be performed using various types of grinders, such as ball mills, hammer mills, or pulverisers. Each type of grinder has its advantages and is selected based on a desired particle size and production scale. For an exemplary but nonlimiting instance, a ball mill may provide fine grinding and is suitable for producing a uniform powder at small scale, while a hammer mill may be more efficient for a larger-scale operation.

[0089] The grinding process may comprise feeding the dried fibers into the grinder, where the fibers may be broken down into smaller particles through mechanical force. Further, the grinder settings, such as speed and blade configuration, may be adjusted to control the particle size. Fine grinding is essential to ensure that the powdered fibers mix well with the binders and form a uniform composite material.

[0090] After grinding, the powdered fibers may be sieved to remove any remaining oversized particles and ensure a consistent particle size distribution. Further, the sieving may be done using a series of mesh screens with decreasing mesh sizes. The sieved powder is then collected and stored in airtight containers to prevent moisture absorption and contamination.The quality of the powdered fibers is crucial for the final product's physical properties. A fine grinded and uniformly ground fibers ensure better interaction with binders resulting in a stronger and more durable leather. Additionally, a smooth, homogeneous powder may be easier to process and coat, leading to a higher-quality final product i.e., banana leather.

[0091] STEP E) APPLYING A SALINE TREATMENT TO THE POWDERED FIBERS:

[0092] The powdered fibers undergo a saline treatment to enhance their binding properties, water resistance properties, surface wettability, fire resistance properties, thermal stability, and durability.

[0093] In an embodiment, a saline solution consisting of sodium chloride (NaCI) and water, at a specific concentration may be used.

[0094] In another embodiment, any of the following saline solution may be used for the objective of saline treatment of the powdered fibers.

[0095] 1. Sodium Chloride (NaCI) Solution comprising Sodium chloride (NaCI) - Common table salt and Distilled water.

[0096] 2. Sodium Chloride and Calcium Chloride (CaCb) Solution comprising Sodium chloride (NaCI), Calcium chloride (CaCL), and Distilled water.

[0097] 3. Sodium Bicarbonate (NaHCOa) Solution comprising Sodium chloride (NaCI), Citric acid, and Distilled water.

[0098] 4. Sodium Chloride and Sodium Carbonate (NazCOa) Solution comprising Sodium chloride (NaCI), Sodium carbonate (NajCOa), Distilled water.

[0099] Further, a plurality of aminosaline solutions comprising combined effects of saline and amino compounds, may further enhance the above-mentioned properties and durability of banana pseudostem fibers. The amino groups may interact with the fibers, improving their reactivity with binders.

[0100] Ingredients of aminosaline solutions:

[0101] • Sodium chloride (NaCI) - Common table salt.

[0102] • Amino acid compound (e.g., L-arginine, L-lysine, or glycine).

[0103] Distilled water.Therefore, aminosaline solutions may also be used in any embodiments of the present invention.

[0104] The powdered fibers are soaked in this solution for a predetermined period, allowing the saline to penetrate and modify the fiber surfaces.

[0105] The saline treatment helps in breaking down any remaining lignin and other non-cellulosic materials, exposing more cellulose surfaces. This process enhances an ability of the fiber to bond with one or more binders or compounds applied in the coating process. After the treatment, the powdered fibers may be filtered and dried again to remove an excess moisture.

[0106] A concentration of the saline solution and the soaking duration are critical parameters that may influence an effectiveness of the saline treatment. An acceptable saline solution may have a concentration of 5-20% sodium chloride by weight. The powdered fibers may be immersed in the saline solution and agitated to ensure an even penetration. A soaking duration may range from a few hours to few days, depending on the fiber properties and desired modification level.

[0107] The saline treatment may enhance the fibers' surface properties, making them more reactive to the one or more binders or compounds, and improving the mechanical strength of the banana leather i.e., the final product. Saline treatment may also reduce a water absorption capacity of the fibers, contribute to a moisture resistance of the final product. After soaking, the fibers may be filtered to remove the saline solution and dried again to the optimal moisture content for coating.

[0108] A proper drying after the saline treatment is essential to prevent clumping and to ensure that the fibers are in a proper condition for the coating process.

[0109] STEP F) COATING THE SALINE-TREATED FIBERS:

[0110] The final step involves coating the saline-treated fibers with one or more layers of a binding and finishing material. A polymer-based binder, such as polyurethane, polyvinyl chloride (PVC), or acrylic polymers, may be applied to the fibers. The polymer-based binder may help in forming a cohesive sheet that mimics the properties of natural leather.

[0111] In an embodiment, a mixture comprising one or more chemical compounds may be applied to the fibers for the coating stage. The mixture may comprise one or morechemical components selected from a group of polyvinyl chloride (PVC), plasticizers such as Kanatol, chemical stabilizers, Bentazone, polyethylene, polyurethane, acrylic polymers, dyes, pigments, sodium salts, potassium salts, Bio polyurethane (PU) adhesive, natural rubber, corn starch, natural adhesive, cork dust, walnut dust, and coconut dust. For the purpose of the present invention, such a mixture also may be categorised as "binder".

[0112] Further, the coating process may involve spreading the binder over the fibers using a blade, roller or any other mechanical assembly to ensure an even distribution of the material. Further, in another embodiment, a plurality of layers may be applied to achieve the desired thickness and texture. Further, each layer may be allowed to cure before applying the next, ensuring proper bonding.

[0113] Further, the binder may be selected based on a desired property of the final product. For a non-limiting example, polyurethane may be used due to its flexibility, durability, and resistance to abrasion. For another non-limiting example, PVC may offer good mechanical properties and is resistant to a large number of chemicals and to moisture. For another non-limiting example, acrylic polymers may provide excellent clarity and are suitable for transparent or translucent coatings.

[0114] The coating process starts with preparing the polymer binder. In an embodiment, the preparation may comprise mixing the binder with appropriate solvents and additives to achieve a desired viscosity and properties.

[0115] The saline-treated fibers are then spread out in a thin layer, and the prepared binder is applied using a blade, roller, spray technique, or any other mechanical assembly to ensure an even distribution of the material. The binder penetrates the fibers, forming a uniform layer that bonds the fibers together.

[0116] In another embodiment, the binder may be mixed with saline treated powdered fibers without any further solvents or additives. The mixture may be directly coated using a blade, roller, spray technique, or any other mechanical assembly to ensure an even distribution of the material.

[0117] In a preferred embodiment, the coating is performed on a surface of a silicone release sheet to ensure controlled coating and a smooth coating surface and texture. The release sheet may be removed once the coating process is completed and the coatedmaterial is significantly dried such that a removal of release sheet would not damage any layer of the final product.

[0118] After a first layer of coating is applied, the material may be allowed to cure at room temperature or in an oven at predetermined temperature, depending on the binder used. The curing of coated material evaporates the solvents and facilitates a cross-linking of polymer chains, resulting in a solid, cohesive sheet of final product. In another embodiments, additional layers may be applied to build up the thickness and achieve the desired texture and mechanical properties.

[0119] In another embodiment, a different binder may be used to build up the thickness, achieve a desired texture, and desired chemical or mechanical properties in the final product.

[0120] In another embodiment, in addition to the binder, a finishing layer may be applied to enhance an appearance and durability of the final product i.e., banana leather. The finishing layer may contain pigments, dyes, or protective coatings, giving the material a desired colour and finish. The finishing layer may also be applied to provide additional physical protection against wear, moisture, and environmental factors.

[0121] In another embodiment, a backing layer may be applied to enhance a flexibility of the final product i.e., banana leather. The backing layer may be a cotton layer, a synthetic woven / non-woven fabric layer, a recycled woven / non-woven fabric layer, or a polymer layer.

[0122] In an embodiment, the coated material may be pressed to achieve the required thickness and texture of the final product. A pressing assembly for this purpose may be one or more weight blocks of different measures, a hydraulic, or a mechanical press to compress the coated material and ensure uniform thickness. A pressure and duration of pressing may be controlled to avoid damaging the material while achieving the desired properties.

[0123] After the coating process, the material may undergo a curing phase to allow the binder to set and achieve optimal adhesion with the fibers. Curing can be carried out under controlled conditions, either through thermal processing at a predetermined temperature or by allowing the material to rest at room temperature for a specific duration. This step ensures that the binder penetrates the fiber matrix effectively, forminga cohesive and durable structure. The curing process may also stabilize one or more coated layers, enhancing their mechanical properties such as but not limited to flexibility, tensile strength, and resistance to wear. A duration and conditions of curing may vary depending on a binder composition, with some formulations requiring gradual setting at ambient conditions to achieve uniform bonding without excessive thermal exposure. In some embodiments, a proper curing may be essential to obtaining a final material having a desired balance of strength, pliability, and longevity.

[0124] The finished product of the present invention is a sustainable, eco-friendly leather alternative with properties similar to natural leather. It may be used in various applications, including fashion, upholstery, and accessories, offering an ethical and environmentally friendly option to traditional leather.

[0125] The above-mentioned method produces a unique type of natural leather substitute (banana leather) that primarily has organic constituent (Banana pseudostem fibers) and better physical and chemical properties than existing different types of synthetic leathers including vegan leather.

[0126] It will be clear to those skilled in the art from the above description that further modifications beyond those discussed may be made without departing from the inventive concepts presented. As a result, the scope of the present invention is not limited to the details provided, but is instead defined by the claims. Furthermore, when interpreting the specification and claims, all terms should be understood in their broadest sense, consistent with the context. Specifically, the terms "include", "including", "comprise" and "comprising" are meant to indicate non-exclusive inclusion of elements, components, or steps, suggesting that additional elements, components, or steps may also be included or combined, even if not explicitly listed. Additionally, when the specification or claims refer to selecting at least one item from a group such as A, B, C, ..., and N, it should be understood as requiring only one item from the group, not necessarily a combination of items.

[0127] The embodiments / applications described hereinabove are exemplary of the present invention. The disclosure may enable those skilled in the art to make and use embodiments having alternative elements that likewise correspond to the elements of the present invention. The intended scope of the present invention may thus include otherembodiments that do not differ or that ^substantially differ from the literal language of the present invention. However, the scope of the present invention is accordingly defined as set forth in the present complete specification.

Claims

WE CLAIM:

1. A method for preparing a natural leather substitute from banana pseudostem fibers, the method comprising steps of:extracting fibers from banana pseudostem;cleaning the extracted fibers to remove components that affect fiber cohesion and binding;drying the cleaned fibers to a predetermined moisture content;grinding the dried fibers into a powdered form;subjecting the powdered fibers to a saline treatment;coating the saline-treated fibers with one or more binders on a release sheet; and curing the coated material under controlled conditions to form the natural leather substitute.

2. The method of claim 1, wherein the step of extracting fibers from banana pseudostem comprises mechanically or manually separating fibers from the pseudostem.

3. The method of claim 1, wherein the removed components in the cleaning step comprise at least one selected from a group comprising polysaccharides, lignin, hemicelluloses, pectin, water-soluble materials, saturated fats, unsaturated fats, metallic compounds, non-metallic compounds, and ash.

4. The method of claim 1, wherein the drying step is performed using at least one technique selected from air drying, sun drying, or oven drying to achieve a moisture content in the range of 5% to 15%.

5. The method of claim 1, wherein the grinding step is performed using a mechanical grinder to obtain powdered fibers of a predetermined particle size distribution.

6. The method of claim 1, wherein the saline treatment comprises immersing the powdered fibers in a saline solution for a predetermined duration to enhance fiber adhesion and compatibility with binders.

7. The method of claim 1, wherein the binder used in the coating step is selected from the group consisting of polyvinyl chloride (PVC), plasticizers, polyurethane, acrylic polymers, bio-based adhesives, natural rubber, corn starch, natural adhesive, cork dust, walnut dust, and coconut dust.

8. The method of claim 1, further comprising pressing the coated material to achieve a desired thickness and texture.

9. The method of claim 1, wherein the release sheet is selected from silicone-coated paper, Teflon sheets, polyethylene films, polypropylene films, or any non-adherent surface capable of facilitating material release.

10. A natural leather substitute produced from banana pseudostem fibers, the material comprising:fibers extracted from at least one banana pseudostem;the fibers being cleaned to remove one or more components selected from a group consisting of polysaccharides, cellulose, hemicelluloses, lignin, pectin, water- soluble materials, saturated fats, unsaturated fats, metallic or non-metallic compounds, and ash;the cleaned fibers being dried to a predetermined moisture content;the dried fibers being ground into a fine powder;the powdered fibers being treated with a saline solution;the saline-treated fibers being coated with at least one binder and a finishing material on a silicone release sheet; andthe coated fibers being cured to form the natural leather substitute with improved mechanical properties.

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