Method for manufacturing hypoallergenic biotic gloves

Abstract

A method for manufacturing bio-gloves significantly reduces protein extraction content and the risk of allergic reactions. The method includes cleaning and heating a mold, immersing the mold in a coagulant solution, and pre-vulcanizing it using alkaline protease, ultraviolet irradiation, and polyols derived from cellulose materials. The latex-coated mold is dried, cleaned, vulcanized using specific vulcanizing agents and accelerators, chlorinated, and then a second impregnated in polyurethane to form a hypoallergenic inner layer. The resulting gloves have a multi-layered structure, including a first layer, a second layer, and a third layer. The first layer comprises nitrile rubber, neoprene rubber, or isoprene rubber combined with polysaccharide biomaterials; the second layer comprises a natural rubber layer or other synthetic rubber combined with polysaccharide biomaterials; and the third layer comprises a polyurethane layer. The final gloves have a bio-content of 3-40%, a tensile strength of 14-40 MPa, an elongation at break of 350-800%, a protein extraction concentration of less than 50 ppm, and a palm thickness greater than 0.03 mm.

Description

[Technical Field]

[0001] This invention relates to the field of disposable gloves, and more specifically, to a method for manufacturing bio-gloves with low protein extraction content to reduce the risk of allergic reactions in users. [Previous Technology]

[0002] Disposable gloves are widely used in various industries, including healthcare, food processing, and chemical handling, to provide a protective barrier against contaminants and harmful substances. Early disposable gloves were primarily made of natural rubber, but natural rubber has long been associated with type I allergic reactions, caused by water-soluble proteins present in latex. Additionally, accelerators and other chemicals used in the vulcanization process of natural rubber can cause type IV chemoallergies. Compared to natural rubber latex gloves, nitrile butadiene rubber gloves (NBR gloves) are favored for their superior oil resistance, chemical resistance, and puncture resistance. However, compared to natural rubber gloves, traditional NBR gloves have poor elasticity. Therefore, there is a need for a glove and its manufacturing method that can possess the elasticity of natural rubber while effectively reducing protein extraction content and allergenicity. [Summary of the Invention]

[0003] To address the aforementioned problems, the primary objective of this invention is to provide a method for manufacturing bio-gloves that significantly reduces protein extraction content and sensitization, thereby lowering the risk of allergic reactions in users. This is achieved through the use of specific proteases, ultraviolet irradiation, and advanced polymer formulations during the pre-vulcanization process, resulting in bio-gloves with enhanced safety and performance characteristics. Another objective of this invention is to enhance the structural integrity and performance of the gloves by using a multi-impregnation technique, combining various polymer materials such as nitrile rubber, chloroprene rubber, isoprene rubber, natural rubber, and polyurethane with polysaccharide biomaterials. This multi-layered structure aims to improve the gloves' chemical resistance, puncture resistance, and abrasion resistance. A further objective of this invention is to optimize the vulcanization process using specific vulcanizing agents and accelerators to ensure that the gloves achieve the desired mechanical properties, such as tensile strength and elongation, while maintaining low protein extraction content. A further objective of this invention is to simplify the manufacturing process by integrating effective cleaning and neutralization steps to remove residual chlorine and other soluble contaminants, ensuring a safe and low-sensitization final product. Based on the above and other objectives, this invention provides a method for manufacturing biogloves that significantly reduces protein extraction content and the risk of allergic reactions in users, while maintaining good elasticity. This method combines several innovative steps and materials to enhance the safety and performance of the gloves. The manufacturing process begins by cleaning the mold in a cleaning tank and heating it in an oven to remove moisture. The mold is then immersed in a coagulant solution in a coagulant impregnation tank and heated in a coagulant oven to fix the coagulant onto the mold. The coagulant ensures proper coagulation and adhesion of the latex to be impregnated. The mold is then immersed in a latex solution. It should be noted that this latex solution has undergone pre-vulcanization treatment, a process involving the addition of 0.1% to 2.0% alkaline protease at a pH of 9.5 to 10.5 and stirring at room temperature for 12 to 48 hours. In addition, the latex solution is irradiated with ultraviolet light at a wavelength of 240-270 nm and an intensity of 1.0-15.0 mW / cm² for 5 seconds to 120 minutes. Furthermore, polyols are incorporated into the latex solution at a concentration of 10-30% of the total solids, reacting with the acid groups in the latex to form a network structure. After the mold is immersed in the latex solution for a period of time, the latex-coated mold is heated in a pre-drying oven to remove moisture, washed with water in a pre-leaching tank for 60 to 300 seconds, and then dried in a drying oven. Next, the latex-coated mold is vulcanized at 100-120°C for 18 to 25 minutes. The latex mixture contains vulcanizing agents and accelerators. These vulcanizing agents and accelerators include inorganic oxides, sulfur, zinc dibutyldithiocarbamate, and zinc diethyldithiocarbamate.The concentrations of inorganic oxides, sulfur, zinc dibutyldithiocarbamate, and zinc diethyldithiocarbamate are 0.6-2 phr, 0.6-2 phr, 0.2-1 phr, and 0.2-1 phr, respectively. After vulcanization, the gloves are washed in a chlorine bath with a concentration of 100-1000 ppm for 60-300 seconds, followed by rinsing with water to neutralize residual chlorine. The gloves are then rinsed with water in a post-drip filtration bath for 60-300 seconds. The next step involves immersing the gloves in a secondary material impregnation bath containing 1-10% polyurethane (PU) polymer material to form an inner layer at least 0.01 mm thick. After drying and demolding, the bio-glove manufacturing is complete. This invention provides a scalable and cost-effective solution for producing high-quality, hypoallergenic nitrile rubber gloves suitable for a wide range of applications, overcoming the limitations of existing methods and providing enhanced safety and performance characteristics. To make the above-mentioned features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings.

Implementation Method

[0005] This invention relates to a novel method for manufacturing bio-gloves, designed to significantly reduce protein extraction content and decrease the risk of allergic reactions. Traditional nitrile rubber gloves are widely used in various industries, including healthcare, food processing, and chemical handling, and are favored for their superior oil resistance, chemical resistance, and puncture resistance. However, despite these advantages, traditional nitrile rubber gloves may pose an allergic risk to some users due to residual proteins and chemicals from the manufacturing process. Furthermore, traditional nitrile rubber gloves also suffer from poor elasticity. In the context of this invention, "protein extraction content" refers to the amount of extractable protein in the glove. Extractable proteins are those that can dissolve from the glove material upon contact with aqueous solutions or under normal use. These proteins are of particular concern because they may come into direct contact with the user's skin and may cause allergic reactions, especially in individuals sensitive to proteins in natural rubber latex. The manufacturing process of the hypoallergenic nitrile rubber bio-gloves of this invention is carefully designed to minimize protein extraction content. This is achieved through a series of pre-vulcanization treatments (described in detail below), including the use of alkaline protease and ultraviolet irradiation. These steps are specifically designed to break down and remove proteins that may be extracted during use, thereby reducing the gloves' allergenic potential. The effectiveness of these treatments in reducing protein extractability has been rigorously tested and validated to meet industry standards such as ASTM D5712. Results show a significant reduction in protein extractability in the gloves of this invention, confirming the hypoallergenic properties of the final product. Reducing protein extractability is a key aspect of this invention as it directly impacts the gloves' hypoallergenic characteristics. By targeting extractable proteins, this process ensures greater glove safety for users, particularly in sensitive environments such as medical and food processing. The manufacturing method described in this invention enhances glove safety and performance by combining specific steps and materials. Key innovations include the use of alkaline protease, UV irradiation, and polyols during pre-vulcanization. Furthermore, a multilayer structure is utilized to integrate the advantages of synthetic and natural rubbers to improve the gloves' mechanical properties and hypoallergenic characteristics. Additionally, the method uses a secondary impregnation process with polyurethane to form an inner layer that comes into contact with the user's skin, further reducing the risk of type IV chemical allergies due to accelerators and other chemicals used during vulcanization. This inner layer acts as a barrier, improving the comfort and safety of the gloves for users with sensitive skin. In addition to reducing sensitization potential, the method of this invention also aims to optimize the mechanical properties of the gloves. The reaction of polyols with acid groups in the latex forms a network structure, improving the tensile strength and elongation of the final product. Multi-layer impregnation further strengthens the gloves, making them suitable for demanding applications. Please refer to Figure 1, which illustrates a flowchart of the manufacturing process of the bio-gloves of this invention. This manufacturing process begins with mold preparation and the pre-vulcanization of the latex.Proper mold preparation is essential to ensure that the finished bio-gloves have a smooth, defect-free surface and that the latex adheres evenly to the mold during manufacturing. The mold preparation process includes two main steps: cleaning the mold (step S110) and heating the mold (step S110) to remove moisture. Before immersing the mold in the coagulant and latex solution, it must be thoroughly cleaned to remove any contaminants that could affect glove quality. As shown in Figure 2, in this embodiment, the mold cleaning process typically includes the following steps: S111 (Initial Rinse): First, rinse the mold with water to remove any loose particles and surface dust. S112 (Detergent Wash): Then, wash the mold with a detergent solution to remove grease, oil, and other organic residues. This step ensures that the mold surface is free of contaminants that could interfere with latex adhesion. S113 (Brushing): The mold can be brushed manually or using a mechanical brush to ensure that all residues are thoroughly removed, especially in areas that are difficult to clean with rinsing alone. S114 (Rinsing): After brushing, thoroughly rinse the mold with clean water to remove any residual detergent and residue. S115 (Initial Drying): The cleaned mold requires initial drying, which can be achieved by air drying or forced ventilation. After cleaning and drying, the mold must be heated to remove any residual moisture (i.e., step S120). This step S120 is used to prevent defects in the subsequent latex coating and ensure proper adhesion of the latex to the mold. As shown in Figure 3, the heating process typically includes the following steps: S121 (Preheating): The mold is placed in an oven and preheated to a specific temperature to ensure all moisture evaporates. The preheating temperature and time are adjusted on a case-by-case basis to achieve the desired effect. S122 (Continuous Heating): The temperature is typically set between 50°C and 100°C, depending on the requirements of the manufacturing process. The mold is heated for a sufficient time to ensure complete drying. S123 (Cooling): After heating, the mold can be allowed to cool slightly before proceeding to the next step of the manufacturing process. This cooling period helps stabilize the mold temperature and ensures uniformity of the latex coating in subsequent steps. After the mold is prepared, the next step is the coagulant impregnation process. This process ensures that the latex film in subsequent steps initially forms and adheres to the cleaned and heated mold. The coagulant impregnation process includes two main stages: immersing the mold in the coagulant solution (step S130) and heating the mold in a coagulant oven (step S140). The purpose of step S130 is to promote the coagulation of the latex applied in subsequent steps on the mold, forming a uniform latex film that will become the glove. As shown in Figure 4, the coagulant impregnation process includes the following steps: S131 (Preparing the coagulant solution): The coagulant solution typically contains calcium nitrate dissolved in a water or alcohol solution. The concentration of calcium nitrate is carefully controlled to ensure effective coagulation and uniform film formation. The coagulant solution may also include additives, such as surfactants or wetting agents, to improve the wettability of the mold and the uniformity of the coating.S132 (Immersion): The mold is immersed in the coagulant solution. Those skilled in the art can control the immersion time to ensure the mold is uniformly coated with the coagulant. Typically, the immersion time ranges from a few seconds to several minutes, depending on the desired coagulant layer thickness and specific process parameters. S133 (Lifting): The mold is slowly lifted from the coagulant solution at a controlled speed to ensure a uniform coating is formed on the mold surface. The lifting speed can be adjusted to affect the thickness of the coagulant layer; a slower lifting speed generally results in a thicker coating. S134 (Preliminary Drying): After immersion, the mold may undergo a brief preliminary drying process to stabilize the coagulant layer before proceeding to the next step. Preliminary drying can be accelerated using ambient air or forced air. After step S130, the mold is heated in a coagulant oven to activate the coagulant and prepare the latex adhesion surface for subsequent steps. As shown in Figure 5, the heating process includes the following steps: S141 (Preheating): The mold is placed in a coagulant oven and preheated to a specific temperature. The preheating step ensures the coagulant layer is properly dried and activated, preparing it for the subsequent latex impregnation process. S142 (Continuous Heating): The temperature in the coagulant oven is controlled within a specific range, typically between 50°C and 100°C, to ensure optimal drying and activation of the coagulant. The duration of heating is also controlled, typically ranging from a few minutes to an hour, depending on process requirements and the thickness of the coagulant layer. Throughout the heating process, temperature and time are monitored and adjusted as needed to ensure uniform activation of the coagulant. This ensures proper adhesion of the latex to the mold in the next step. S143 (Cooling): After a period of continuous heating, in some embodiments, the mold is allowed to cool slightly before the latex impregnation process. This cooling period helps stabilize the coagulant layer, ensuring a uniform latex film formation. Next, steps such as latex impregnation (step S160) and pre-drying (step S170) are performed. It should be noted that in this embodiment, steps S160 to S170 need to be repeated twice to form the first layer 110 and the second layer 120 of the bio-glove 100 as shown in Figure 8, respectively. Step S160 is to form a uniform latex layer on the mold and enhance the mechanical properties of the glove. Referring to Figure 6, immersing the mold in the latex solution includes the following steps: S161 (Preparation of latex solution): In the first execution of step S160, the latex solution is prepared by mixing nitrile rubber latex with polysaccharide biomaterials and various additives to achieve the desired properties. In other embodiments, the latex solution can be other synthetic rubbers, such as chloroprene rubber and isoprene rubber combined with polysaccharide biomaterials. In the second execution of step S160, the latex solution is prepared by mixing natural rubber latex with various additives to achieve the desired properties. These additives may include stabilizers, surfactants, and other compounds to improve the stability and uniformity of the latex.In addition, the latex solution is thoroughly homogenized to ensure compositional consistency. S162 (Immersion): The heated mold coated with a coagulant is immersed in the latex solution. The immersion time is controlled to achieve the desired latex layer thickness. Typically, the immersion time ranges from a few seconds to several minutes. S163 (Lifting): The mold is lifted from the latex solution. The lifting speed affects the thickness and uniformity of the latex layer, so the lifting speed needs to be controlled. Next, step S170 is performed. In one embodiment, step S170 involves heating in a pre-drying oven to remove excess moisture from the latex-coated mold. In this step, the mold is placed in a pre-drying oven with a set temperature typically between 50°C and 80°C, a temperature range sufficient to evaporate moisture without degrading the latex layer. The drying duration typically lasts from 5 to 30 minutes, depending on the latex layer thickness and process requirements. After completing step S170, step S160 is performed a second time. The main component of the latex solution used in the second execution of step S160 is natural rubber latex. It is important to note that, regardless of whether it is the first or second execution of step S160, the latex solution used must undergo a pre-vulcanization process (step S150). Since natural rubber contains a relatively high amount of protein, step S150 is necessary to remove the protein. Referring also to Figure 7, step S150 of the pre-vulcanization process includes the following steps: S151 (Adding alkaline protease): This step can occur before the mold is immersed in the latex solution. Alkaline protease is added to the latex solution at a concentration of 0.1% to 2.0% by weight. The protease helps to break down proteins in the latex, reducing the allergenicity of the final glove. Furthermore, the pH of the latex solution is adjusted, for example, to 9.5 to 10.5 to optimize the activity of the alkaline protease. This pH range ensures that the protease can effectively break down proteins during the pre-vulcanization process. Moreover, the latex solution with added protease is stirred at room temperature for 12 to 48 hours. This prolonged agitation ensures that the protease has sufficient time to act on the protein, further reducing its content in the final product. S152 (UV Irradiation): The latex-coated mold is irradiated with a UV lamp in the wavelength range of 240-270 nm. This specific wavelength range effectively decomposes proteins and other organic compounds in the latex. The intensity of the UV irradiation is controlled between 1.0 and 15.0 mW / cm². The irradiation time can range from 5 seconds to 120 minutes, depending on the desired protein reduction level and other process parameters. Additionally, it is worth noting that in other embodiments, the entire latex solution can be irradiated before the mold is immersed in the latex solution, depending on the requirements. S153 (Polyol Incorporation): This step occurs before the mold is immersed in the latex solution, where a polyol is incorporated into the latex solution at a concentration of 10-30% of the total solids in the latex solution.These polyols react with the acid groups in the latex to form a network structure that enhances the mechanical properties of the glove. In one embodiment, the polyols chemically react with the carboxylic acid groups in the latex to form ester bonds, crosslinking the latex molecules. This crosslinking forms a network structure in the latex, improving its tensile strength, elasticity, and resistance to water-soluble protein dissolution. In this embodiment, the polyols are also derived from cellulose materials. Referring to Figure 1, after latex impregnation, pre-vulcanization, and pre-drying are completed, pre-leaching (step S180) is performed. This step involves cleaning the mold in a pre-leaching tank to remove water-soluble proteins and other impurities. In step S180, the mold is immersed in a cleaning solution in the pre-leaching tank, which is typically water. In some cases, additional agents, such as surfactants or mild detergents, may be added to enhance the removal of impurities. The mold is cleaned in the pre-leaching tank for 60 to 300 seconds. The specific duration depends on the impurity content and the requirements of the manufacturing process. Additionally, the cleaning solution may be gently stirred or agitated to improve the efficiency of protein and impurity removal. This ensures that all surfaces of the latex-coated mold are thoroughly cleaned. In this step S180, the cleaning solution is typically maintained between 20°C and 40°C, which helps to increase the solubility of proteins and other contaminants, promoting their removal. After completing steps such as pre-drying and pre-leaching, the vulcanization process is initiated (step S190). The vulcanization process involves heating the latex-coated mold under the action of a vulcanizing agent and an accelerator to form crosslinks between rubber molecules, thereby improving the elasticity, strength, and durability of the glove. In this step S190, the latex-coated mold is placed in a vulcanization oven, and the temperature is controlled to ensure that the vulcanization process proceeds efficiently without causing degradation of the latex or other materials. In this embodiment, the temperature is typically maintained between 100°C and 120°C. In this embodiment, the mold heating time ranges from 18 to 25 minutes. Of course, those skilled in the art can adjust the heating time according to the thickness of the latex layer, the composition of the latex mixture, and other process parameters. During vulcanization, specific vulcanizing agents and accelerators are added to the latex. These substances promote the cross-linking of rubber molecules. The vulcanizing agents and accelerators typically include the following compounds: Inorganic oxides: In this embodiment, the concentration of inorganic oxides is 0.6-2 phr. Inorganic oxides enhance the stability and mechanical properties of rubber by promoting effective cross-linking. Sulfur: Sulfur is the primary vulcanizing agent, and its concentration in this embodiment is 0.4-2 phr. It forms cross-links between rubber molecules, greatly improving the elasticity and durability of the gloves. Zinc dibutyldithiocarbamate: Zinc dibutyldithiocarbamate acts as a secondary accelerator, and its concentration in this embodiment is 0.2-1 phr. It accelerates the vulcanization process, reduces the time required to complete cross-linking, and improves the efficiency of the process.Zinc diethyldithiocarbamate: Zinc diethyldithiocarbamate is another secondary accelerator, with a concentration of 0.2-1 phr in this embodiment. Similar to zinc dibutyldithiocarbamate, it accelerates the vulcanization process, ensuring uniform crosslinking within the latex matrix. The vulcanizing agent and accelerator are thoroughly mixed into the latex solution prior to the mold impregnation process (step S160). This ensures that these compounds are uniformly distributed within the latex matrix, promoting consistent vulcanization across all parts of the glove. Next, refer to Figure 1. The post-vulcanization chlorination treatment (step S210) and washing (step S220) are used to remove any residual proteins, chemicals, and other contaminants that may remain after vulcanization, further reducing the risk of allergic reactions and ensuring the cleanliness and safety of the final product. In step S210, the purpose of the chlorination washing step is to remove residual proteins and other contaminants from the glove surface. Chlorination treatment is particularly effective in denaturing proteins, making them insoluble in the latex and easier to wash, which helps reduce the glove's sensitizing potential. In this embodiment, the chlorine solution is prepared by dissolving chlorine in water, typically at a concentration between 100 and 1000 ppm, sufficient to denature proteins without damaging the latex material. In step S210, the vulcanized gloves, along with the mold, are immersed in the chlorine solution. The immersion time is carefully controlled to ensure thorough treatment. Typically, the gloves are immersed for 60 to 300 seconds. During immersion, the chlorine solution can be gently agitated to improve treatment effectiveness and ensure uniform contact of chlorine across all glove surfaces. After immersion in the chlorine solution, the gloves undergo a rinsing process in step S220 to neutralize residual chlorine and remove any proteins and other contaminants dissolved in the chlorine solution. In this step, the gloves are rinsed with clean water to wash away the chlorine solution. Multiple rinsing cycles may be performed to ensure complete removal of chlorine and other residues. In some cases, a neutralizing agent, such as sodium thiosulfate, may be added to the rinse water to ensure complete neutralization of residual chlorine. Next, step S230 is performed, rinsing in a post-drip tank to remove any remaining soluble contaminants, ensuring the gloves are ultimately clean. This step further reduces the risk of allergic reactions, ensuring the gloves are free of any residual chemicals and proteins. The post-drip tank contains clean water, typically maintained at room temperature or lukewarm (20°C to 40°C) to improve the solubility of remaining contaminants. The rinsing process involves immersing the gloves in the cleaning solution for 60 to 300 seconds. The immersion time is controlled to ensure thorough cleaning. Simultaneously, gentle agitation or stirring of the cleaning solution can be used to enhance the efficiency of contaminant removal, ensuring all surfaces of the gloves are thoroughly cleaned. Then, step S240 is performed, conducting a secondary immersion process to coat the inner surface of the bio-gloves with a layer of polyurethane, providing a smooth, non-irritating barrier, reducing the risk of type IV chemical allergies, and improving overall user comfort.The polyurethane solution is prepared by dissolving or dispersing a polyurethane polymer material in a suitable solvent or aqueous medium. The concentration of the polyurethane solution is adjusted to achieve the desired properties of the inner coating. Typically, the weight percentage concentration of polyurethane in the polyurethane solution ranges from 1% to 10%, a concentration that ensures a uniform and effective coating that adheres well to the latex surface. The secondary immersion process involves immersing the glove, still on the mold, into the polyurethane solution. The immersion time is controlled to ensure a thin, uniform layer of polyurethane is applied to the inner surface of the glove. Immersion times typically range from a few seconds to several minutes, depending on the desired coating thickness. The mold is slowly lifted from the polyurethane solution at a controlled speed; the lifting speed affects the thickness and uniformity of the polyurethane layer, with slower lifting speeds generally resulting in a thicker coating. Furthermore, in this embodiment, the formed polyurethane inner layer is typically 0.01 to 0.04 mm thick. This thickness provides an effective barrier against allergens and irritants without significantly affecting the glove's flexibility and tactile sensitivity. Following this, a drying step (step S250) and a demolding step (step S260) are performed to ensure the gloves are completely dry and safely removed from the mold without compromising their integrity or quality. Step S250 ensures that any residual solvent or moisture from the secondary impregnation process is removed. In this step, the gloves are placed in a drying oven or subjected to forced air drying at a temperature controlled between 50°C and 70°C. This temperature range is sufficient to evaporate any residual moisture or solvent without damaging the latex or polyurethane layers. The drying time is carefully controlled, typically lasting 20 to 60 minutes, depending on the characteristics of the gloves and the thickness of the layers. This time ensures the gloves are thoroughly dried and fully vulcanized. Proper air circulation is maintained within the drying oven to ensure all gloves dry evenly. This prevents localized overheating or undried conditions that could affect the quality and performance of the gloves. The drying process is monitored to ensure that the temperature and duration remain within the specified range. Any deviations are corrected immediately to ensure consistent quality. Step S260 is the process of carefully removing the fully dried gloves from the mold. In manual processes, skilled workers carefully peel the gloves from the mold. This method requires precise manipulation to avoid tearing or stretching the gloves. In automated processes, mechanical equipment gently removes the gloves from the mold. Automated systems can improve efficiency and consistency, reducing the risk of damage. In some cases, a release agent or lubricant may be applied lightly to facilitate the demolding process. This helps prevent the gloves from sticking to the mold, reducing the risk of tearing. Mechanical equipment such as air jets or robotic fingers can be used to assist in removing the gloves from the mold. These devices gently lift the edges of the gloves, making them easier to peel. After demolding, the gloves undergo a thorough inspection to check for defects or damage. This includes checking for thickness uniformity, tears or holes, and overall quality. Defective gloves are identified and removed from the production line. The remaining gloves are sorted and prepared for packaging.Samples are taken from each batch of gloves for testing to ensure they meet specified standards for tensile strength, elongation, and low allergenicity. This ensures the gloves perform as intended in their intended application. The gloves are packaged according to industry standards and ready for distribution. Proper packaging helps maintain the quality and hygiene of the gloves until delivery to the end user. Please refer to Figure 8, which illustrates a structural schematic diagram of one embodiment of the bio-glove of the present invention. As shown in Figure 8, the bio-glove 100 has a multi-layered structure, the main purpose of which is to enhance its mechanical properties, chemical resistance, and low allergenicity. The composition, function, and thickness of each layer in the bio-glove 100 will be described in detail below. In this embodiment, the multi-layered structure of the bio-glove 100 includes a first layer 110, a second layer 120, and a third layer 130. The first layer 110 is mainly composed of nitrile rubber combined with polysaccharide biomaterials. Nitrile rubber has excellent oil resistance, chemical resistance, and puncture resistance. In addition, the first layer 110 can also use or be blended with other synthetic rubbers, such as neoprene and isoprene rubber combined with polysaccharide biomaterials, to achieve specific properties. As the main structural component of the bio-glove 100, the first layer 110 provides the necessary strength, durability, and chemical resistance. The use of nitrile rubber or other synthetic rubbers ensures that the bio-glove 100 can withstand harsh environments and chemical exposures, making it suitable for a variety of industrial and medical applications. The second layer 120 is primarily composed of natural rubber, chosen for its superior elasticity, tensile strength, and comfort, which enhances the overall flexibility and fit of the bio-glove 100. The second layer 120 provides the glove with additional strength and elasticity, improving wearer comfort and fit. The natural rubber layer also enhances tactile sensitivity, making the glove suitable for delicate handling. Furthermore, in other embodiments, the second layer 120 can also be composed of other synthetic rubbers combined with polysaccharide biomaterials. Synthetic rubbers, such as nitrile rubber or neoprene, provide superior resistance to oils, chemicals, and punctures, making the glove suitable for use in harsh industrial environments and chemical processing applications. The addition of polysaccharide biomaterials (such as cellulose or starch) enhances the environmental friendliness of gloves, making them a more sustainable option. These biomaterials are biodegradable, helping to reduce the product's carbon footprint. The combination of synthetic rubber and polysaccharide biomaterials also provides a balanced way to maintain the glove's mechanical properties. Polysaccharides can act as fillers or reinforcing agents, improving the strength and durability of the synthetic rubber layer. Such gloves are not only strong and durable but also lightweight and comfortable for extended wear. Furthermore, the combination of synthetic rubber and polysaccharide biomaterials ensures low protein extraction content, thereby reducing the risk of allergic reactions. This makes the gloves suitable for users with sensitivities to natural rubber proteins, expanding their applications in diverse fields such as medical, food processing, and laboratory settings.In summary, the second layer 120, whether composed of natural or synthetic rubber combined with polysaccharide biomaterials, plays a crucial role in enhancing the overall performance of the glove. It provides the necessary strength, elasticity, and comfort while also meeting specific requirements for chemical resistance, sustainability, and hypoallergenicity. This versatility ensures that the bio-glove 100 is suitable for a wide range of applications, offering high performance and user satisfaction. In this embodiment, the third layer 130 is primarily composed of polyurethane, which possesses hypoallergenic properties and the ability to form a smooth, non-irritating inner surface. The main function of the third layer is to provide a hypoallergenic barrier, reducing the risk of type IV chemical allergies. The third layer 130 improves comfort for users with sensitive skin, providing a smooth inner surface that makes the bio-glove 100 easy to put on and take off. The third layer 130 is formed during a secondary impregnation process (step S240). In this embodiment, the thickness of the first layer 110 typically ranges from 0.01 mm to 0.2 mm. This range ensures that the bio-glove 100 has sufficient strength and chemical resistance while maintaining flexibility. The second layer 120 also ranges in thickness from 0.01 mm to 0.2 mm. This second layer 120 increases the overall thickness of the glove, enhancing its elasticity and comfort without making it too bulky. The third layer 130 ranges in thickness from 0.01 mm to 0.04 mm. This layer is designed to be thin enough to maintain flexibility and comfort while providing an effective hypoallergenic barrier. The total thickness of the glove, combining all three layers, typically ranges from 0.03 mm to 0.44 mm. The multi-layered structure of the bio-glove 100 in this embodiment balances the needs for strength, flexibility, and hypoallergenicity, making it a high-performance glove suitable for a variety of applications. Finally, the bio-glove manufactured through this innovative process exhibits a range of superior properties, making it ideal for a variety of demanding applications. The bio-content of the bio-glove ranges from 3% to 40%, reflecting the inclusion of renewable and biodegradable materials such as polysaccharide biomaterials. This significant bio-content highlights the glove's environmental sustainability, meeting the growing market demand for eco-friendly products. The gloves offer tensile strengths ranging from 14 to 40 MPa, ensuring they possess the necessary mechanical strength to withstand harsh conditions. This high tensile strength is crucial for applications requiring high stress and tensile strength, such as industrial environments, medical procedures, and laboratory work. The increased tensile strength also contributes to glove durability, reducing the frequency of replacements and thus providing cost-effectiveness. The bio-gloves exhibit elongation at break ranging from 350% to 800%, demonstrating excellent flexibility and elasticity. This characteristic is particularly important to ensure that the bio-gloves can stretch and conform to the user's hand without tearing, providing a comfortable and secure fit. High elongation at break is essential for maintaining dexterity and tactile sensitivity, enabling users to easily perform delicate and precise operations.A key feature of bio-gloves is their low protein extraction concentration, below 50 ppm. This low concentration is achieved through a pre-vulcanization process, including the use of alkaline protease and UV irradiation, which effectively breaks down and eliminates extractable proteins. By reducing the protein extraction content, the gloves significantly reduce the risk of allergic reactions, making them suitable for individuals with latex sensitivity or allergies. This hypoallergenic characteristic enhances the gloves' suitability for use in medical, food handling, and other sensitive environments. The palm thickness of the gloves is greater than 0.03 mm, providing a balance between protection and tactile sensitivity. This thickness ensures that the gloves provide an adequate barrier against contaminants and hazardous substances while maintaining the flexibility required for delicate movements. The optimal palm thickness also contributes to the overall durability of the gloves, enabling them to withstand abrasion in a variety of applications. In summary, bio-gloves made using this method possess a range of advanced properties: Bio-content: 3% to 40%, highlighting the use of renewable materials; Tensile strength: 14 to 40 MPa, ensuring mechanical strength; Elongation at break: 350% to 800%, providing excellent flexibility and elasticity. Protein extraction concentration: below 50 ppm, reducing the risk of allergic reactions. Palm thickness: greater than 0.03 mm, balancing protection and tactile sensitivity. These properties make biogloves ideal for a variety of applications, providing high performance, safety, and sustainability. The innovative combination of materials and advanced manufacturing processes ensure that the gloves meet the stringent requirements of various industries, providing user comfort and environmental benefits. To verify the hypoallergenicity and environmental sustainability of the biogloves, the applicant commissioned two comprehensive test reports from a third-party organization. These test reports provide important insights into the protein extraction content and biobased carbon content of the gloves, demonstrating their suitability for sensitive users and environmentally friendly applications. The first test report, conducted by SGS Taiwan Ltd. (Report No.: HQ40011 / 2023), focuses on analyzing the water-soluble protein extraction content in the biogloves of this invention. Using the ASTM D5712-15 method, specifically the modified Lowry method, the analysis results show that the protein extraction content in the test sample is 27.5 ppm. This low content of water-soluble extractable protein indicates a low risk of allergic reactions in the bio-gloves of this invention. The test was conducted under controlled environmental conditions: an ambient temperature of 25 ± 3°C and a relative humidity of 65 ± 10%, using a Shimadzu UV-1700 UV-VISIBLE spectrophotometer. The results confirm that the protein extract content of the bio-gloves of this invention is within an acceptablely low range, making them suitable for individuals with latex sensitivities.The second test report, provided by Beta Analytic (report number: Beta-660692), assessed the bio-based carbon content of the bio-gloves. Using ASTM D6866-22 Method B (AMS) TOC, the report showed that the gloves contain 37% bio-based carbon, meaning that 37% of the carbon content in the gloves comes from renewable biomass sources, such as plant or animal by-products, while the remaining 63% comes from fossil sources such as petroleum. The measured percentage of modern carbon (pMC) was 36.61 ± 0.12 pMC. This test was also adjusted using an atmospheric adjustment factor to reflect contemporary CO2 levels. This high proportion of bio-based carbon underscores the environmental sustainability of the gloves and demonstrates their alignment with the growing demand for environmentally friendly products. The analysis was conducted according to stringent standards, and the results were certified to ISO / IEC 17025:2017 test PJLA #59423, ensuring high accuracy and reliability. These test reports collectively validate the dual advantages of the bio-gloves of this invention: low allergenicity and a significant amount of renewable materials used. An SGS report confirms that the gloves have extremely low protein extraction content, reducing the likelihood of allergic reactions, while a Beta Analytic report highlights the gloves' commitment to sustainability, showing that a significant portion of their composition is derived from natural sources. These findings make the bio-gloves of this invention a superior choice for health-conscious and environmentally conscious consumers, ensuring safety, comfort, and environmental friendliness in a variety of applications. Although the invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the invention. Those skilled in the art can make modifications and refinements without departing from the spirit and scope of the invention. Therefore, the scope of protection of this invention should be determined by the appended claims. [Simplified Explanation of the Diagram]

[0004] Figure 1 is a flowchart illustrating the manufacturing process of the bio-glove of the present invention. Figure 2 is a flowchart illustrating the process of cleaning the mold of the present invention. Figure 3 is a flowchart illustrating the heating process of the present invention. Figure 4 is a flowchart illustrating the coagulant impregnation process of the present invention. Figure 5 is a flowchart illustrating the heating process of the present invention. Figure 6 is a flowchart illustrating the process of immersing the mold in the latex solution of the present invention. Figure 7 is a flowchart illustrating the pre-vulcanization process of the present invention. Figure 8 is a structural schematic diagram of one embodiment of the bio-glove of the present invention.

Claims

1. A method for manufacturing bio-gloves, comprising: (a) Provide a mold suitable for manufacturing gloves, wherein a coagulant is fixed on the surface of the mold; (b) Immersing the mold in a latex solution, and then pre-drying the latex-coated mold to form a latex-coated mold; (c) Washing the latex-coated mold with water; (d) Drying the latex-coated mold; (e) Vulcanizing the latex-coated mold to cure the latex and produce a glove; (f) Chlorinating the vulcanized glove to remove residual proteins and contaminants; (g) Rinsing the chlorinated glove to remove residual chlorine; (h) Immersing the glove in a primary and secondary material impregnation tank containing a polyurethane polymer material, wherein the polyurethane weight percentage concentration is 1% to 10%; (i) Drying the glove; and (j) Demolding the glove; wherein, steps (b) through (d) are performed at least twice before step (e). In the first execution of steps (b) to (d), the latex solution comprises synthetic rubber combined with biopolysaccharides; in the second execution of steps (b) to (d), the latex solution comprises natural or synthetic rubber combined with biopolysaccharides. Prior to the execution of steps (b) to (d), the latex solution has undergone a pre-vulcanization treatment, which includes: adding an alkaline protease to the latex solution at a weight percentage of 0.1% to 2.0% of the total weight of the latex solution, and stirring at room temperature at pH 9.5 to 10.5 for 12 to 48 hours; and exposing the latex-coated mold to a UV lamp with a wavelength of 240 to 270 nm and an intensity of 1.0 to 15.0 mW / cm² for 5 seconds to 120 seconds. The process involves irradiating the latex with ultraviolet light for several minutes; and adding a polyol to the latex solution, wherein the weight of the added polyol is 10% to 30% of the total solids in the latex solution, so that the polyol reacts with the acid groups in the latex to form a network structure, wherein the polyol is a polyol derived from cellulose material; wherein the bioglossy gloves manufactured by the above method have an extractable protein content of less than 50 ppm.

2. The method of claim 1, wherein step (e) comprises being performed at a temperature of 100-120°C for 18-25 minutes, and the latex comprises a vulcanizing agent and an accelerator.

3. The method for manufacturing bio-gloves as described in claim 2, wherein the vulcanizing agent and accelerator comprise inorganic oxides, sulfur, zinc dibutyldithiocarbamate, and zinc diethyldithiocarbamate; wherein, The concentrations of inorganic oxides, sulfur, zinc dibutyldithiocarbamate, and zinc diethyldithiocarbamate were 0.6–2 phr, 0.2–1 phr, and 0.2–1 phr, respectively.

4. The method of manufacturing bio-gloves as claimed in claim 1, wherein step (f) comprises immersing the glove in a chlorine solution with a concentration of 100-1000 ppm for 60-300 seconds.

5. The method of manufacturing bio-gloves as claimed in claim 1, wherein step (h) is to form an inner layer about 0.01-0.04 mm thick, and the bio-glove has a tensile strength of 14-40 MPa and an elongation at break of 350%-800%.

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