Elastomer articles coated with bio-based hydrogels and methods for producing the same

Abstract

The present invention relates to a bio-based hydrogel coating composition for elastomer articles, which overcomes the problems of sweat accumulation, skin dryness, irritation, and difficulty in wearing wet gloves, while also providing an alternative to powdered elastomer articles. [Solution] The bio-based hydrogel coating is designed to improve the wearability, comfort, and hygiene of the above-mentioned elastomer articles. This innovative formulation eliminates the need for powder-based coatings while providing a multifaceted solution that overcomes the problems of sweat accumulation, skin dryness, irritation, and the difficulty of wearing wet gloves.

Description

Technical Field

[0001] The present invention relates to coatings and elastomeric articles. In particular, it relates to bio-based polymer hydrogel coatings and elastomeric articles coated therewith, and provides improvement of problems associated with long-term glove wearing, including sweat accumulation due to occlusion, skin dryness caused by transdermal water loss, irritation by chemical residues of gloves, and difficulty in wearing during glove replacement.

Background Art

[0002] Elastomeric materials, such as those used in the manufacture of elastomeric articles such as gloves, are widely used in various industries and medical settings to provide hand barrier protection against various hazards, including chemical substances, biological agents, and physical wounds. However, long-term glove wearing can cause several problems, including skin dryness, irritation, sweating, and difficulty in wearing wet gloves. To reduce the potential health problems associated with powdered gloves, powder-free gloves have been developed as a safer alternative.

[0003] Several patents, including U.S. Patent Publication No. 20060062815(A1), U.S. Patent No. 5614202(A), U.S. Patent Publication No. 20070053958(A1), U.S. Patent No. 6274154(B1), U.S. Patent No. 6423328(B2), and U.S. Patent No. 6630152(B2), disclose gloves incorporating moisturizers or skin soothing agents to alleviate skin problems caused by wearing gloves. In addition, gloves have been designed with specific coatings or materials to facilitate easier application, particularly when wet, as disclosed in U.S. Patent Publication No. 20080034467(A1), U.S. Patent No. 8313833(B2), International Publication No. 2006071308, U.S. Patent Publication No. 20220175068(A1), U.S. Patent Publication No. 20050132466(A1), and U.S. Patent Publication No. 20060141186(A1). Furthermore, as disclosed in Canadian Patent No. 3042804(C) and U.S. Patent No. 10023718(B2), developments have also been made to eliminate glove-related allergens by developing gloves that do not contain accelerators.

[0004] The problems associated with glove use are multifaceted. Prolonged wear of gloves can lead to moisture buildup, which can cause skin irritation and discomfort. Powdered gloves, once widely used, are now recognized as harmful to health due to the potential for inhalation and skin irritation. In addition, the need for moisturizers to soothe and protect the skin during prolonged glove use is extremely important. To prevent exposure to chemicals and skin reactions, gloves should also provide an effective barrier against chemical allergens. Finally, ease of putting on is essential to minimize the risk of contamination and improve usability. In particular, none of the existing powder-free elastomer products effectively address the above problems. None of the existing powder-free elastomer products have been able to provide an elastomer product that can address multiple problems, such as overcoming sweat buildup while providing moisturizing effects, providing a barrier against chemical allergens, and providing ease of putting on for the user. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] U.S. Patent Application Publication No. 20060062815(A1) [Patent Document 2] U.S. Patent No. 5614202(A) [Patent Document 3] U.S. Patent Application Publication No. 20070053958(A1) [Patent Document 4] U.S. Patent No. 6,274,154 (B1) [Patent Document 5] US Patent No. 6423328(B2) [Patent Document 6] US Patent No. 6630152(B2) [Patent Document 7] U.S. Patent Application Publication No. 20080034467(A1) [Patent Document 8] US Patent No. 8313833(B2) [Patent Document 9] International Publication No. 2006071308 [Patent Document 10] U.S. Patent Application Publication No. 20220175068(A1) [Patent Document 11] U.S. Patent Application Publication No. 20050132466(A1) [Patent Document 12] U.S. Patent Application Publication No. 20060141186(A1) [Patent Document 13] Canadian Patent No. 3042804(C) [Patent Document 14] US Patent No. 10023718(B2) [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] Therefore, the object of the present invention is to provide elastomer articles such as gloves coated with a biopolymer hydrogel to address the problems associated with prolonged glove wear. Specifically, the present invention aims to overcome the problems of sweat accumulation, skin dryness and irritation, and the difficulty of wearing wet gloves, while also providing an alternative to powdered elastomer articles. The biopolymer hydrogel coating is designed to improve the wearability, comfort, and hygiene of the elastomer articles. [Means for solving the problem]

[0007] Embodiments of the present invention provide a biopolymer hydrogel composition for use as a coating for elastomer articles, comprising a biopolymer hydrogel formed from polysaccharides extracted from mushrooms; glycerol; a preservative; and a thickener, wherein the polysaccharides are extracted from one or a combination of Tremella fuciformis, Lentinula edodes, Ganoderma lucidim, or Inonotus obliquus.

[0008] Embodiments of the present invention provide biopolymer hydrogel compositions for use as coatings, wherein the compositions exhibit improved hygroscopic properties, skin hydration properties, physical barrier properties, or ease of application to the user.

[0009] Embodiments of the present invention provide a method for producing an elastomer article having a biopolymer hydrogel composition coating, the method comprising the following steps: - The process of preparing and cleaning the mold; - The process of applying a coagulant to the mold; - A step of immersing a mold in aqueous polymer latex to form the body of the article; - A process of pre-leaching the formed article, followed by cooling; - A process of chlorinating and neutralizing an item; - A step of immersing an article in a coating composition to coat the outer surface of the article; - A step of drying the coated article; and - A step of demolding the article from a mold such that the outer surface becomes an inner surface having a coating by inverting and peeling off or equivalent means, comprising, wherein the coating composition is a biopolymer hydrogel coating according to the above embodiment.

[0010] An embodiment of the present invention is to provide an elastomeric article having a biopolymer hydrogel composition with outer and inner surfaces formed from an elastomeric material, and on the inner surface, a biopolymer hydrogel composition according to any one of the above embodiments is applied.

[0011] An embodiment of the present invention is to provide an elastomeric article having a biopolymer hydrogel composition containing an elastomeric material, and the elastomeric article is formed from an elastomeric material composed of a bio-based monomer selected from, but not limited to, bio-butadiene monomer, bio-acrylonitrile monomer, or bio-methacrylic acid monomer.

Brief Description of the Drawings

[0012] [Figure 1] FIG. 1 shows an exemplary overview of a method for synthesizing a biopolymer hydrogel composition for coating an elastomeric article. [Figure 2] FIG. 2 shows conventional means for forming an elastomeric glove having a coating. [Figure 3] FIG. 3 shows the results of a user perception experiment comparing an uncoated glove and a glove coated with a biopolymer hydrogel.

Embodiments for Carrying Out the Invention

[0013] It should be understood that the embodiments disclosed herein are illustrative of the principles of the claims. Other possible modifications are included in the claims. Therefore, as an example, and not limiting, other embodiments may be used according to the disclosure herein.

[0014] Therefore, the claims are not limited to the embodiments as strictly shown and described. Throughout this specification and the subsequent claims, unless otherwise specified in the context, the words “comprise” and “comprises” or “including” are used. The variations such as "ru (comprising)" are understood to mean that they include the integer or process, or group of integers or processes, that is listed, but do not exclude any other integer or process, or group of integers or processes.

[0015] In this specification, no reference to any prior publication (or information derived therefrom) or any publicly known matter shall be construed as acknowledging, acknowledging, or suggesting in any way that such prior publication (or information derived therefrom) or publicly known matter forms part of the common general knowledge within the scope of the attempt relating to this disclosure.

[0016] Figure 1 shows an illustrative overview of a method for synthesizing biopolymer hydrogels derived from Tremella fuciformis polysaccharide (TFP) compositions used for coating elastomer articles.

[0017] Embodiments of the present invention provide a composition for use as a coating for elastomer articles, comprising a mushroom polysaccharide extract extracted from mushrooms; glycerol; a preservative; and a thickener, which comprises a polymer hydrogel formed using a thickener.

[0018] Polymer hydrogels are formed using the synthesis process shown in Figure 1. While not limited to mushrooms, polymer hydrogels are formed starting with the formation of a dispersion containing polysaccharides obtained from mushrooms. Glycerol is incorporated into the dispersion along with preservatives and thickeners.

[0019] In a further embodiment of the present invention, an ela comprising a polymer hydrogel, according to the following steps, A composition is provided for use as a coating for ostomy articles: (a) A TFP extract, in a quantity of 5% by mass relative to the mass of water, derived from a polysaccharide source such as Tremella fuciformis (but not limited to this), is combined with water to form a dispersion using a high-speed mixer that preferably provides high shear conditions of approximately 8000 rpm. The shearing process is continued until the dispersion mixture becomes a homogeneous mixture; (b) Next, 2% by mass of glycerol relative to the mass of TFP is incorporated into the dispersion, and stirring is continued at a low speed at a temperature of about 80°C, preferably for about 20 minutes. This step enables significant crosslinking of the polysaccharide. Physical crosslinking is facilitated by the addition of glycerol, which interacts with the carboxyl and hydroxyl groups in the polysaccharide chain through the mechanism of disruption of hydrogen bonds and hydrophobic interactions; (c) The low-speed stirring process is preferably maintained at 80 rpm throughout the entire crosslinking process. (d) In order to increase viscosity and prevent microbial growth during storage, thickeners and preservatives are further added to the starch dispersion slurry.

[0020] It should be noted that the use of TFP extract in this disclosure is interchangeable with mushrooms as an alternative source of polysaccharides.

[0021] In the processing of compositions for producing polymer hydrogel coatings, the formation of polysaccharide dispersions includes a polysaccharide source, glycerol, a thickener, and a preservative. The polysaccharide source is selected from, but is not limited to, Tremella fuciformis, Lentinula edodes, Inonotus obliquus, Ganoderma lucidum, or any other similar mushroom species. For example, Tremella fuciformis is a naturally occurring and sustainable mushroom, offering a compelling alternative to conventional synthetic materials for glove coatings. Its biodegradability and reduced chemical footprint contribute significantly to environmental sustainability, making it a preferred choice for environmentally conscious consumers and businesses. Its natural properties and generally safe nature minimize the potential health hazards associated with some synthetic materials, making it a safer option for consumers.

[0022] In this invention, glycerol is primarily used as a crosslinking agent. However, it should be understood that equivalent crosslinking effects can be obtained with other crosslinking agents such as propylene glycol, polyethylene glycol, and sorbitol. The thickener (viscosity enhancer) is selected from, but is not limited to, gums such as guar gum, xanthan gum, locust bean gum, and gum arabic; cellulose derivatives such as methylcellulose, carboxymethylcellulose (CMC), hydroxyethylcellulose (HEC), and microcrystalline cellulose; and synthetic polymers such as polyacrylamide and polyvinyl alcohol (PVA). The preservative is selected from, but is not limited to, phenoxyethanol, chlorphenesin, potassium sorbate, and sodium benzoate.

[0023] The object of the present invention is to produce a composition for use as a coating for elastomer articles that exhibits higher hygroscopicity compared to existing coatings.

[0024] Polymer hydrogel coatings are formed from TFP extracts that readily form homogeneous hydrogel dispersions. The hydrogel absorbs water through both bonding and retention mechanisms that begin on the hydrogel surface. The absorption process begins when water molecules interact with hydrophilic functional groups, such as hydroxyl (-OH) groups, on the TFP chains located on the hydrogel surface. These hydroxyl groups, abundant in the polymer chains, have a strong affinity for water and form hydrogen bonds with surrounding water molecules. As water interacts with the surface, The water molecules diffuse into the hydrogel complex, which has an interconnected three-dimensional network structure formed by the crosslinking process. This crosslinked network structure creates a stable matrix of interconnected polymer chains, forming spaces or pores within its structure that can physically confine water molecules. This network structure (established by crosslinking) is crucial for maintaining the integrity of the hydrogel and preventing the polymer chains from dissolving or separating after absorbing water.

[0025] The object of the present invention is to provide a composition for use as a coating for elastomer articles that can provide a moisturizing effect to the user and thus replenish moisture to the skin while the elastomer article is in use.

[0026] Hydrogels are polymers with high water-retention capabilities, and when incorporated into gloves, they also provide an effective way to moisturize hands. Upon interacting with moisture, the smaller TFP components diffuse from the hydrogel matrix and engage with the skin surface. Because these TFP molecules are small, they penetrate the stratum corneum (SC) and reach deeper epidermal layers. At this point, the TFP molecules in the epidermal layers form a hydrophilic matrix that binds and retains both internal and sweat-derived moisture. This process establishes a moisture-retaining environment within the epidermis, improving hydration and the overall moisture balance of the skin. The moisturizing effect can be further adjusted by changing the TFP molecular weight, coating thickness, and hydrogel composition.

[0027] The object of the present invention is to provide a composition for use as a coating for elastomer articles that can provide a physical barrier layer that protects the skin from direct contact with chemical residues or allergens present in the elastomer article.

[0028] Elastomer articles such as gloves are essential for protection in various industries, but they may incidentally contain allergens and chemicals that can pose a risk to the wearer. These contaminants may originate from the manufacturing process, environmental exposure, or even specific use of the gloves. For example, latex gloves often contain proteins that can trigger allergic reactions in sensitive individuals, while residual accelerators in gloves can cause type IV hypersensitivity in some people. Chemical barrier coatings are crucial to mitigate these risks and protect the wearer's health. Such barriers can effectively prevent the transfer of allergens and chemicals from the glove surface to the skin, thereby reducing the likelihood of adverse reactions and ensuring wearer safety. Biopolymer hydrogel compositions forming coatings for elastomer articles such as gloves provide a barrier that effectively protects the skin from direct contact with harmful chemical residues or allergens that may be present in the elastomer material itself or may adhere to the surface during use. This coating forms a physical barrier between the skin and potential irritants, and its purpose is to significantly reduce the risk of skin reactions, allergies, and other harmful health effects associated with glove use.

[0029] The object of the present invention is to provide a composition for use as a coating for elastomer articles that can be easily attached by the user.

[0030] The process of putting on elastomer articles such as gloves may be referred to as "wearing" or "wearability." When considering the wearability of elastomer articles such as gloves, one way to determine wearability is to examine the coefficient of friction through a friction test. The coefficient of friction is a dimensionless number that quantifies the amount of friction between two contacting surfaces. It is a measure of the amount of resistance these surfaces have to sliding or slipping through each other. A lower coefficient of friction indicates that the two surfaces are smoother together, and therefore easier to put on. The presence of a TFP hydrogel coating results in a lower coefficient of friction overall, and therefore, wearing is easier under both dry and wet skin conditions. The process is facilitated. Specifically, when using the gloves, the slippery texture of the hydrogel and the excellent water absorption capacity of the hydrogel coating, which easily absorbs moisture from the surface of the user's hands, facilitate the putting process under both dry and wet hand conditions.

[0031] Therefore, an embodiment of the present invention provides an elastomer article incorporating a biopolymer hydrogel composition for use as a coating on the elastomer article, according to the following steps (shown in Figure 2): (a) The mold is prepared and cleaned with acidic and alkaline cleaning agents to remove dirt and residue. Typically, a first coat of coagulant containing, but not limited to, calcium nitrate or calcium carbonate as a latex coagulant and stearate as an anti-tack agent is applied to the mold to ensure proper glove formation and smooth peeling from the mold. Optionally, a wetting agent containing Teric 320 may be added to ensure proper wetting of the mold surface for a homogeneous coagulant coating. (b) The composition is then immersed in an aqueous polymer latex that forms the glove body. The latex immersion may consist of one or more immersion processes to achieve the desired thickness. (c) The elastic articles formed by this process undergo a pre-leaching process to remove excess protein and impurities, followed by a curing process in an oven with circulating hot air to dry out any remaining moisture by evaporation and to facilitate the crosslinking process of the gloves. After crosslinking, the gloves exhibit improved durability, resistance to tearing and stretching, improved chemical and heat resistance, and enhanced structural stability. (d) After the curing process is complete, the final articles are subjected to a cooling process, followed by chlorine treatment by immersing the elastomer articles in an 800-1200 ppm chlorinated aqueous solution to improve surface properties. Proper chlorine treatment reduces the stickiness of the gloves and makes them smoother for easier wear. (e) After chlorination, the gloves are subjected to neutralization by washing with a base such as sodium hydroxide or ammonia to remove residual chlorine and adjust the surface pH, and are subjected to a post-leaching process to remove residual impurities. (f) Next, the elastomer article is immersed in a TFP dispersion slurry formed by the process shown in Figure 1 (as described above in the specification of this patent application), thereby coating the outer surface of the glove with the TFP dispersion slurry. (g) Next, the elastomer article is subjected to further drying to remove water, thereby forming a solid coating on the outer surface of the elastomer article. (h) Next, the coated elastomer article is demolded from the mold by an inversion and peeling process, thereby inverting the outer surface (as it was on the mold) to become the inner surface of the elastomer article, as illustrated in Figure 1. By this manufacturing method, the final gloves exhibit enhanced hygroscopicity, moisture retention, good fit, physical barrier protection, and skin soothing effects, facilitated by the biopolymer hydrogel coating.

[0032] The object of the present invention is to manufacture an elastomer article, such as a glove, having an outer surface and an inner surface, by the method described above. The biopolymer hydrogel is applied to the outer surface, which is then inverted to become the inner surface. Thus, the final manufactured article has an outer surface and an inner surface coated with a biopolymer hydrogel coating.

[0033] The object of the present invention is to produce an elastomer material that is thin and can be considered powder-free. As disclosed herein, by using a biopolymer hydrogel coating, an ultrathin film can be formed on an elastomer material (e.g., gloves), resulting in a powder-free design. This thin coating layer reduces the need for conventional powder coatings that can absorb moisture from the skin, potentially causing allergic reactions or leaving residues. Hydrogel coatings also offer improved hygroscopicity, moisture retention, good wearability, and material properties. It provides a natural barrier protection and skin soothing effect, making it ideal for prolonged wear in a variety of applications, particularly in medical and industrial settings. According to the ASTM D6124 standard, a powder-free glove must contain less than 2 mg of powder per glove. When incorporated into gloves, the biopolymer hydrogel coating results in a glove with a powder content of less than 2 mg, thus meeting the ASTM standard.

[0034] Regarding the thickness of elastomer articles, gloves are preferably less than 0.2 mm thick, more preferably between 0.05 mm and 0.2 mm. Gloves less than 0.2 mm thick are considered thin gloves. Gloves of this thickness are designed to enhance tactile sensitivity, manual dexterity, and comfort in applications requiring precision and fine motor skills. These gloves are particularly suitable for medical procedures requiring delicate manipulation, such as microsurgery, and industrial work involving small or delicate parts. The reduced bulkiness and improved comfort of ultra-thin gloves contribute to improved visual-hand coordination, reduced fatigue, and improved overall performance in tasks requiring high tactile sensitivity and precision. Therefore, an object of the present invention is to manufacture elastomer articles, such as gloves, that are considered thin gloves with a thickness of less than 0.2 mm.

[0035] The object of the present invention is to produce a fully bio-based and sustainable elastomer material. Novel elastomer articles are formed from elastomer materials incorporating one or more bio-based monomers selected from, but not limited to, bio-butadiene monomers, bio-acrylonitrile monomers, or bio-methacrylic acid monomers. These bio-based monomers are derived from renewable and sustainable biological sources and significantly reduce the carbon footprint associated with the production of elastomer articles compared to conventional articles that utilize petroleum-derived monomers. The incorporation of these bio-based monomers facilitates the development of sustainable elastomer materials used in the production of elastomer articles, while simultaneously potentially improving performance properties, including durability, flexibility, chemical resistance, adhesion, crosslinking efficiency, and other desired properties.

[0036] While both latex and biolatex are natural rubber materials, their sources and allergenicity differ significantly. Latex originates from rubber trees, while biolatex originates from plant-based sources other than rubber trees. Biolatex production may have a lower environmental impact compared to conventional latex production and offers a more sustainable alternative to conventional latex derived from rubber trees. Biolatex production often involves less intensive agricultural work, potentially resulting in a lower overall environmental impact compared to latex production. In addition, because biolatex relies on renewable plant-based resources, it contributes to reducing the carbon footprint. Therefore, using biolatex in various applications can contribute to a more sustainable and environmentally conscious approach. Biolatex is a natural rubber material composed of long chains of repeating monomer units (such as biobutadiene monomer, bioacrylonitrile monomer, or biomethacrylic acid monomer).

[0037] Therefore, a further embodiment of the present invention provides an elastomer article incorporating a biopolymer hydrogel composition for use as a coating on the elastomer article, according to the following steps (shown in Figure 2), wherein conventional polymer latex is replaced by a polymer latex made from a fully bio-based (bio-based) monomer selected from, but not limited to, biobutadiene monomer, bioacrylonitrile monomer, or biomethacrylic acid monomer: (a) The type is prepared and washed with acid and alkaline cleaning agents to remove dirt and residue. Typically, the coagulant contains, but is not limited to, calcium nitrate or calcium carbonate as a bio-based latex coagulant and stearate as an anti-tack agent. A first coat is applied to the mold to ensure proper glove formation and smooth peeling from the mold. Optionally, a wetting agent containing Teric 320 may be added to ensure proper wetting of the mold surface for a homogeneous solidifying agent coating. (b) The composition is then immersed in an aqueous biopolymer latex that forms the glove body. The latex immersion may consist of one or more immersion processes to achieve the desired thickness. (c) The elastic articles formed by this process undergo a pre-leaching process to remove excess protein and impurities, followed by a curing process in an oven with circulating hot air to dry out any remaining moisture by evaporation and to facilitate the crosslinking process of the gloves. After crosslinking, the gloves exhibit improved durability, resistance to tearing and stretching, improved chemical and heat resistance, and enhanced structural stability. (d) After the curing process is complete, the final articles are subjected to a cooling process, followed by chlorine treatment by immersing the elastomer articles in an 800-1200 ppm chlorinated aqueous solution to improve surface properties. Proper chlorine treatment reduces the stickiness of the gloves and makes them smoother for easier wear. (e) After chlorination, the gloves are subjected to neutralization by washing with a base such as sodium hydroxide or ammonia to remove residual chlorine and adjust the surface pH, and are subjected to a post-leaching process to remove residual impurities. (f) Next, the elastomer article is immersed in a TFP dispersion slurry formed by the process shown in Figure 1 (as described above in the specification of this patent application), thereby coating the outer surface of the glove with the TFP dispersion slurry. (g) Next, the elastomer article is subjected to further drying to remove water, thereby forming a solid coating on the outer surface of the elastomer article. (h) Next, the coated elastomer article is demolded from the mold by an inversion and peeling process, thereby inverting the outer surface (as it was on the mold) to become the inner surface of the elastomer article, as illustrated in Figure 1. By this manufacturing method, the final gloves exhibit enhanced hygroscopicity, moisture retention, good fit, physical barrier protection, and skin soothing effects, facilitated by the biopolymer hydrogel coating. [Examples]

[0038] method In the following comparative examples, the following apparatus was used to process the composition on a laboratory scale. 1. Silverson Mixer (L5M-A, Silverson, USA) 2. Overhead stirrer (EUROSTAR 60 digital, Ika®-Werke GmbH & Co.KG, Germany) 3. Water bath heating system

[0039] Materials used in the examples The materials and methods described herein are provided as examples and are not intended to limit the scope. Other materials and methods may be used to practice the present invention, and it should be understood that the scope of the present invention is defined solely by the appended claims.

[0040] Mushroom polysaccharide extracts, including those from Tremella fuciformis, Lentinula edodes, Inonotus obliquus, and Ganoderma lucidum, can be used as the main component for the synthesis of the renewable polymer hydrogel in this invention. TFP extracts were commercially available from Shandong Focusfreda Biotech Co., Ltd (Treme-HA®, China) as exemplary candidates for hydrogel dispersions. Glycerol (USP 99.7%) was obtained from Stallion Chemical (M) Sdn. Bhd. (Malaysia). Storage The compounding agent and thickener were supplied by Shanghai Cosroma Biotech Co., Ltd (China) and Xi'an Best Bio-Tech Co., Ltd. (China), respectively.

[0041] The renewable NBR latex (biolatex) used in the manufacture of gloves is a bio-based alternative to conventional petrochemical-derived NBR latex. It is produced from biobutadiene, bioacrylonitrile, and biomethacrylic acid, using glucose or other sugars, starch-based materials, and greenhouse gases (GHG) CO2 as renewable natural or artificial photosynthetic biomass feedstock. The chemical synthesis and physical properties of renewable NBR latex (biolatex) are the same as those of petrochemical-derived NBR latex.

[0042] Synthesis method The synthesis process for the biopolymer hydrogel coatings disclosed above, as shown in Figure 1, is outlined below.

[0043] The formation of the polymer hydrogel began by dispersing a 5% (weight / weight) renewable Tremella fuciformis polysaccharide (TFP) extract in water until homogeneous using an 8000 rpm high-shear Silverson mixer. Glycerol was added at a 2% (weight / weight) ratio relative to the TFP mass, and the dispersion was stirred at low speed for 30 minutes using an overhead stirrer. The TFP dispersion was heated at 80°C for 20 minutes to achieve sufficient physical crosslinking for the formation of a hydrogel dispersion. The physical crosslinking of the TFP chains was facilitated by glycerol acting as a crosslinking agent, interacting with the carboxyl and hydroxyl groups within the polysaccharide chains. The stirring speed was maintained at 80 rpm using a flat-bladed propeller (10 cm × 10 cm) throughout the crosslinking process. Next, the hydrogel dispersion was diluted to 2% (weight / weight) and maintained at 60°C with continuous stirring at 80 rpm. Preservatives and thickeners were added in the final stage at concentrations of 0.02% (weight / weight) and 0.01% (weight / weight), respectively.

[0044] Next, the TFP hydrogel was coated onto the rubber gloves by a dip coating method before the final oven stage. Rubber elastomer gloves (shown in Figure 2 and disclosed above), manufactured with bio-based latex according to conventional glove manufacturing practices, were immersed in the hydrogel coating solution for a predetermined residence time. The hydrogel coating layer was dried in the final oven and then inverted in a peeling process, so that the hydrogel coated surface, which had previously been facing outwards, became the inner surface of the glove, i.e., the wearing side.

[0045] In vitro moisture absorption capacity of gloves The absorbency of the hydrogel coating was evaluated using an in vitro method modified from the ISO 9073-6:2000 standard used for evaluating the absorbency of nonwoven fabrics. 600 mg of a 0.5% (weight / volume) sodium chloride solution was spread uniformly on the inner surface of pre-weighed gloves as artificial sweat. The gloves were then left in a controlled environment for 20 minutes to simulate clinical wear conditions. Next, the inner coating was exposed to the external environment under a fume hood for 2 minutes to remove excess liquid. Finally, the gloves were weighed, and their absorbency was determined based on the results from four pairs of gloves.

[0046] Next, the absorption capacity is calculated based on the following formula. Absorption capacity (mg) = Final weight of glove - Initial weight of glove

[0047] Evaluation of the powder content of gloves The powder content of TFP hydrogel-coated gloves was evaluated according to ASTM D6124 standards. In this case, to be considered a powder-free glove, the powder content must be less than 2 mg / glove. It is necessary.

[0048] Determination of the coefficient of friction (COF, μ) The coefficient of friction (μ) of a hydrogel-coated rubber substrate was measured using a COF tester (MH2-500N, IMADA Co., LTD, Japan) combined with a digital force gauge (ZTS-5N, IMADA Co., LTD, Japan). The analysis was performed under dry and wet conditions in accordance with the ASTM D1894 standard. The test samples were cut to a size of 250 mm × 130 mm and placed on a flat surface with the mounting side facing upwards. A 200 g sled was slid across the test surface at a speed of 150 mm / min in cycle mode. The average static μ value was calculated using Force Recorder Standard software, and the result was obtained from three consecutive experiments for each sample set.

[0049] In the test under wet conditions, the warped surface was wetted with approximately 200 mg of deionized water. The water was evenly distributed by swiping the warped surface back and forth five times in both the horizontal and vertical directions. The subsequent procedure was as described above.

[0050] Table 1 shows a comparison of moisture absorption capacity, powder content, and surface friction coefficient between gloves coated with biopolymer hydrogel and uncoated gloves. [Table 1]

[0051] The above example demonstrates the gel-forming properties of TFP, which readily dissolves in water to form a homogeneous hydrogel dispersion. The TFP hydrogel is formed by physically crosslinking the TFP chains with the assistance of glycerol as a crosslinking agent, resulting in a continuous network structure film upon drying. The powder content of 0.16 mg / glove detected in gloves coated with TFP hydrogel confirmed its powder-free coating properties (Table 1). Appropriate microstructure of the hydrogel matrix is ​​necessary for excellent water capture and retention. As shown in Table 1, the TFP hydrogel exhibited significantly higher (p=0.0005) in vitro absorption (105.5 mg) compared to the negative control (40.2 mg), representing a 146% improvement in absorption. The hydrogel's excellent water retention capacity is attributed to the abundant hydroxyl (OH) groups in the high-molecular biopolymer network structure chains, which can capture and incorporate surrounding water molecules via hydrogen bonding.

[0052] The friction test was conducted to investigate the coefficient of friction between two surfaces: a sled and an elastomer glove. The wearability of the glove was strongly correlated with the coefficient of friction; the lower the friction, the smoother the surface. Therefore, it indicates that application is easy. As shown in Table 1, the presence of the TFP hydrogel coating resulted in a 30% overall reduction in the mean static friction coefficient (μ) under dry conditions (TFP hydrogel: 0.40±0.01, negative control: 0.57±0.03). On the other hand, under wet conditions (TFP hydrogel: 0.75±0.05, negative control: 1.28±0.07), a reduction of approximately 41% in static μ was recorded. This suggests that the TFP hydrogel coating facilitates the application process under both dry and wet hand conditions due to the slippery texture of the hydrogel and its excellent water absorption capacity that easily removes moisture from the surface of the hand.

[0053] User Perception Experiment User perception experiments were conducted to evaluate several parameters, including the fit under wet and dry hand conditions, sweat absorption, moisturizing effect, and finally, barrier protection against potential glove allergens and skin soothing effect. All glove samples were conditioned at room temperature for 24 hours. Prior to the experiment, subjects were asked to wash their hands thoroughly before wearing the gloves. Subjects were provided with either treated gloves (coated with TFP hydrogel) or untreated gloves (uncoated / negative control) in a blinded and randomized manner. The glove arrangement for each subject was recorded, and the experiment was repeated the following day with the gloves in the reverse arrangement. Subjects continued their daily work for either a 10-minute or 60-minute test period. The 10-minute test was used to evaluate features including fit under wet conditions, sweat absorption, and moisturizing effect, while the 60-minute test evaluated fit under dry conditions, as well as the barrier protection and skin soothing features of the coating. To evaluate wearability in a wet state, participants received a spray of a total of 600 mg of artificial sweat (0.5 wt / wt% NaCl). The palm and back of the hand surfaces were sprayed twice each, followed by two rubs to distribute evenly across the palm. Conversely, to evaluate wearability in a dry state, the gloves were worn directly on dry hands. User feedback was collected using a questionnaire on a 5-point Likert scale (1-5, from strongly disagree to strongly agree).

[0054] Several features of the gloves, including wearability under dry and wet hand conditions, sweat absorption, moisturizing effect, barrier protection, and skin soothing effect against residual chemicals, were evaluated through user perception experiments. The results are summarized in Figure 3, based on the mean Likert scale scores obtained for each evaluated feature. Glove wearability was evaluated based on ease of application, level of resistance, and level of adjustment required during application. Participants were then asked to score their level of agreement with the description that each side of the glove was easy to apply. For TFP hydrogel, all participants experienced faster and easier application in a dry state with less resistance and less adjustment required (TFP hydrogel: 4.5, negative control: 3.0). When applied with wet hands, the difference in perceived wearability was more pronounced, with a difference of approximately 70% identified based on the mean scores assigned (TFP hydrogel: 4.3, negative control: 2.5). These results are consistent with a significant reduction in the coefficient of friction compared to the negative control (Table 1), and therefore indicate improved wearability of gloves coated with TFP hydrogel.

[0055] The amount of sweat felt on the surface of the hand after removal was used as the criterion for evaluating the sweat-absorbing effect. Although the experimentally measured absorption rate increased by 146% (Table 1), only 60% of subjects showed a positive response to the sweat-absorbing properties of TFP hydrogel after 10 minutes of wear (TFP hydrogel: 4.2, negative control: 3.0). This may be due to absorption at the milligram (mg) level, which is an extremely small amount for all subjects to perceive. In contrast, the moisturizing effect was evaluated based on both visual and tactile judgments after removing the gloves. The majority of subjects (80%) felt a moisturizing effect during the 10 minutes of wearing TFP hydrogel, and some of the feedback from positive respondents included smoothness and a silky feel. It was found that the moisturizing effect is due to the ability of TFP to penetrate through SC to the core of the epidermis and retain moisture, and to function as a moisturizing barrier on SC that minimizes transepidermal water evaporation.

[0056] Furthermore, when the negative control (4.0) was worn for an extended period (60 minutes), most subjects experienced mild skin irritation, particularly itching and dryness. Notably, all respondents reported no skin irritation with the TFP hydrogel (5.0). This suggests that, in addition to its skin-soothing properties, TFP hydrogel acts as a physical barrier layer protecting the skin from direct contact with chemical residues or allergens in the gloves. In summary, TFP hydrogel (4.1) received a higher overall comfort score compared to the negative control (2.6). Overall, the perception of gloves coated with TFP hydrogel was better than that of the negative control. 80% of subjects agreed that TFP hydrogel provided a superior wearing experience and preferred gloves coated with TFP hydrogel. The improved comfort is attributed to the overall benefits offered by TFP hydrogel, including ease of application in both dry and wet conditions, sweat absorption, moisture retention, barrier protection, and skin soothing properties.

[0057] statistical analysis All measurements were performed in multiple repeated experiments as specified in each section, and the results were expressed as mean ± standard error (SE). GraphPad Prism 8.0.2 (GraphPad, CA, USA) was used to graph the data and to determine statistical significance (p<0.05) between means using Student's t-tests.

Claims

1. A biopolymer hydrogel composition for coating elastomer articles, comprising a biopolymer hydrogel formed from polysaccharides extracted from mushrooms.

2. A biopolymer hydrogel composition for use as a coating for elastomer articles, comprising the biopolymer hydrogel described in claim 1, glycerol, a preservative, and a thickener.

3. A biopolymer hydrogel composition according to claim 1 or 2, exhibiting improved hygroscopic properties.

4. A biopolymer hydrogel composition according to any one of claims 1 to 3, which exhibits skin moisture replenishment properties.

5. A biopolymer hydrogel composition according to any one of claims 1 to 4, which exhibits physical barrier properties that provide the user with barrier protection and skin soothing properties.

6. A biopolymer hydrogel composition according to any one of claims 1 to 5, which facilitates easy application.

7. The biopolymer hydrogel composition according to any one of claims 1 to 6, wherein the polysaccharide is extracted from one or a combination of Tremella fuciformis, shiitake mushroom, Reishi mushroom, or Chaga mushroom.

8. A method for producing an elastomer article having a biopolymer hydrogel composition coating, comprising the following steps: - The process of preparing and cleaning the mold; - A step of applying a coagulant to the mold; - A step of immersing the mold in aqueous polymer latex to form the body of the article; - A step of pre-leaching the formed article, followed by cooling; - A step of chlorinating and neutralizing the aforementioned article; - A step of immersing the article in a coating composition in order to coat the outer surface of the article; - A step of drying the coated article; and - A step of demolding the article from the mold by inverting and peeling it off or by equivalent means such that the outer surface becomes the inner surface having the coating. A method comprising the above, wherein the coating composition is a biopolymer hydrogel coating according to any one of claims 1 to 7.

9. An elastomer article having a biopolymer hydrogel composition: Outer surface, and The inner surface is formed from elastomer material. An elastomer article comprising a biopolymer hydrogel composition according to any one of claims 1 to 7, wherein the inner surface is coated with the biopolymer hydrogel composition according to any one of claims 1 to 7.

10. The biopolymer hydrogel composition according to any one of claims 1 to 7, the method according to claim 8, or the elastomer article according to claim 9, wherein the elastomer article is formed from an elastomer material formed from a monomer of a bio-based monomer.

11. The biopolymer hydrogel composition according to any one of claims 1 to 6, the method according to claim 8, or the elastomer article according to claim 9, wherein the elastomer article is formed from an elastomer material formed from a monomer selected from biobutadiene monomer, bioacrylonitrile monomer, or biomethacrylic acid monomer.

12. The biopolymer hydrogel composition according to any one of claims 1 to 7, the method according to claim 8, or the elastomer article according to claim 9, wherein the elastomer article is a glove.

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