A method for preparing modified cellulose fiber nonwoven material for ice crystal films

Abstract

This invention relates to a method for preparing modified cellulose fiber nonwoven materials for ice crystal films. A porous membrane, consisting of a cellulose fiber spunlace nonwoven fabric with a three-dimensional texture, is tightly sandwiched between a soluble metal anode and an inert cathode to construct an electrolytic cell. The electrolytic cell is immersed in an electrophoretic modification solution containing negatively charged biocompatible macromolecules. A DC voltage is applied between the two electrodes, driving the macromolecules to actively penetrate into the spunlace nonwoven fabric via an electric field. An electrochemical oxidation reaction causes the soluble metal anode to release crosslinking ions in situ. These crosslinking ions then react with the migrated macromolecules in situ, forming a gel network within the fiber network. Finally, the product is obtained after rinsing and drying. This invention makes the preparation process more efficient, achieving deep and uniform penetration and efficient in-situ fixation of the modifier in the fiber substrate. It also protects and even strengthens the original physical texture during the modification process, resulting in high-performance gel mask materials.

Description

Technical Field

[0001] This invention relates to the field of electrophoretic electrolysis mask material preparation technology, and in particular to a method for preparing modified cellulose fiber nonwoven material for manufacturing ice crystal films using electrophoretic electrolysis process. Background Technology

[0002] In today's skincare market, consumers have placed higher demands on the user experience and functionality of face mask products, driving the market towards premiumization and differentiation. Among these, a type of cellulose-based nonwoven mask with a unique three-dimensional texture (such as "ice diamond pattern") and gel-like feel—the Ice Diamond Pattern Gel Mask—is particularly popular. Often referred to as "ice crystal mask" in the market due to its crystal-clear appearance and unique gel texture, this type of product is highly favored by consumers. Its three-dimensional physical texture increases the contact area with the skin, helping to enhance the carrying capacity and penetration of the essence; simultaneously, its gel-like texture gives the material excellent adherence and a bouncy feel, significantly improving the user experience.

[0003] Currently, the mainstream technical approach for preparing such mask materials involves obtaining a cellulose nonwoven fabric with a predetermined physical texture through hydroentangling, followed by a complex chemical finishing process to impart gel properties. A representative traditional method typically includes: first, swelling the cellulose nonwoven fabric with a strong alkaline solution (such as sodium hydroxide) to open the internal channels of the fibers; then, using mechanical methods such as padding, allowing gelling agents such as sodium alginate to penetrate and adhere to the fibers; finally, through a series of wet chemical treatments such as drying, ion exchange in acidic or saline solutions (e.g., using calcium ions), and multiple washing and re-drying, the water-soluble sodium alginate is converted into a water-insoluble calcium alginate gel.

[0004] However, the aforementioned existing technologies have several inherent technical defects in practical applications. First, their processes are cumbersome and environmentally burdensome, involving multiple unit operations such as "alkali treatment - padding - acid / salt treatment - washing," resulting in high energy consumption, low production efficiency, and the large-scale use of strong acids and alkalis generates difficult-to-treat acid and alkaline wastewater, which is inconsistent with the development trend of green manufacturing. Second, the uniformity of modifier distribution and fixation rate are difficult to guarantee. Mechanical padding, as a passive application method, often leads to the modifier accumulating on the fiber surface and failing to penetrate the core layer, resulting in incomplete curing. Some gelling agents are lost during washing or use, affecting the gel stability and water-locking performance of the product. Furthermore, the treatment with high-concentration alkaline solutions may cause some damage to the molecular chains of cellulose, leading to a decrease in the mechanical strength and toughness of the final material. Finally, during the multiple soaking, padding, and washing processes, the wet fiber cloth is prone to deformation, which may blur the fine texture formed in the early physical molding, reducing the appearance and recognizability of the product.

[0005] Therefore, there is an urgent need in this technical field for a novel, efficient and environmentally friendly preparation method that abandons the traditional and complex chemical processing path and solves the aforementioned defects in the existing technology. Summary of the Invention

[0006] To address the technical problems of the prior art, this invention provides a method for preparing modified cellulose fiber nonwoven materials for ice crystal films. This method makes the preparation process more efficient and environmentally friendly, and improves product performance and texture. It achieves deep and uniform penetration and in-situ efficient fixation of the modifier in the fiber substrate, and protects or even strengthens the original physical texture during the modification process. This results in the preparation of high-end gel mask materials with superior performance and a greener production process, meeting market demands.

[0007] This invention discloses a method for preparing modified cellulose fiber nonwoven material for ice crystal films, comprising the following steps:

[0008] First, in step 1, a reaction substrate was prepared as the basis for subsequent electrochemical modification. It should be noted that the method used in this step, which involves preparing a nonwoven fabric with a three-dimensional texture via hydroentangling, is a mature or conventional technology in the field. Specifically, this step uses naturally derived cellulose fibers as raw materials, forming a uniform fiber web through pre-processes such as opening and carding. This is fundamental to ensuring the uniformity of the final product. Subsequently, the fiber web is laid on a mesh curtain with a specific preset three-dimensional texture pattern, and then reinforced by hydroentangling using high-pressure water jets. The physical impact of hydroentangling not only causes the fibers to entangle and form a nonwoven fabric with a certain mechanical strength, but also forces the fiber web to accurately replicate the three-dimensional morphology of the mesh curtain surface, thereby forming the preset three-dimensional texture on the nonwoven fabric. This invention uses the product prepared by this prior art—a cellulose fiber hydroentangled nonwoven fabric with a three-dimensional texture—as the starting material or reaction substrate for a novel subsequent electrochemical modification process. Its physical structure is also an important component of the final product's function and appearance.

[0009] The core innovation of this invention lies in the fact that, after obtaining the above-mentioned spunlace nonwoven fabric substrate, a series of unique electrochemical finishing steps (i.e., steps 2 to 5) are used to functionalize and modify it in a completely new way.

[0010] In step 2, the core reactants for functionalization modification are prepared. This step involves dissolving a negatively charged biocompatible macromolecule, such as sodium alginate, in deionized water to form an electrophoretic modification solution. The key here is that the selected macromolecule must carry a net negative charge, a prerequisite for its directional migration in the subsequent electric field; simultaneously, its biocompatibility ensures the safety of the final product for applications such as skin contact. Deionized water is used to avoid interference from impurity ions in the subsequent electrochemical process.

[0011] Subsequently, in step 3, a device for realizing the core reaction of this invention is constructed. This step uses the spunlace nonwoven fabric obtained in step 1 as a porous membrane, tightly sandwiched between a soluble metal anode and an inert cathode. This "sandwich" structure is the ingenious aspect of this invention. The spunlace fabric, as a porous membrane, has an internal fiber network and pore structure that constitutes the microscopic site for the reaction; the soluble metal anode, such as a calcium plate, not only acts as a conductor but, more importantly, serves as an "in-situ generator" of the crosslinking agent; while the inert cathode, such as a graphite plate, stably completes the circuit construction. This structure tightly bonds the reactants (spunlace fabric) to the source of the crosslinking agent (anode), laying the physical foundation for the subsequent efficient reaction.

[0012] Step 4 is the core execution stage of the technical solution of this invention, in which the modifier is penetrated and immobilized in situ. After immersing the electrolytic cell assembled in step 3 in the electrophoretic modification solution prepared in step 2 and applying a DC voltage, two key physicochemical processes occur simultaneously and synergistically. On the one hand, under the action of the electric field, the negatively charged biocompatible macromolecules in the electrophoretic modification solution are strongly driven to overcome fluid resistance and actively, rapidly, and directionally migrate towards the anode. During the migration process, they penetrate the pores on the surface of the spunlace nonwoven fabric and penetrate deep into the interior of the fiber network, achieving deep and uniform penetration of the entire three-dimensional substrate. On the other hand, the soluble metal plate, acting as the anode, undergoes an electrochemical oxidation reaction simultaneously under the action of the potential, thereby continuously and controllably releasing metal cations as crosslinking agents at the interface closely attached to the spunlace nonwoven fabric. The synergistic effect of these two processes is that the macromolecules that migrate to the vicinity of the anode immediately encounter the high concentration of newly generated crosslinking ions there and instantly undergo a crosslinking reaction to form a water-insoluble gel network. This synchronized "migration-generation-crosslinking" mechanism firmly and in situ locks the modifier into the interior and surface of the fiber.

[0013] Finally, in step 5, the modified material undergoes post-treatment. A simple deionized water rinse removes any remaining electrolytes from the surface, followed by drying to obtain the final modified cellulose fiber nonwoven material. Since the gel network is firmly fixed through insoluble chemical cross-linking, simple rinsing does not result in significant loss of the modifier.

[0014] Preferably, the cellulose fiber in step 1 is selected from at least one of lyocell fiber, cuprammonium fiber, viscose fiber, or cotton fiber; and the negatively charged biocompatible macromolecule in step 2 is sodium alginate, sodium hyaluronate, or carboxymethyl chitosan, with a mass concentration of 0.5% to 2.0% in the electrophoretic modification solution. Specifically, in this scheme, the cellulose fiber in step 1 is specifically selected from at least one of lyocell fiber, cuprammonium fiber, viscose fiber, or cotton fiber. These fibers are all commonly used regenerated cellulose fibers or natural cellulose fibers in the art, possessing good biocompatibility, moisture absorption, and mechanical strength, providing a reliable substrate for the preparation of high-performance nonwoven fabrics. Meanwhile, the negatively charged biocompatible macromolecule in step 2 is specifically sodium alginate, sodium hyaluronate, or carboxymethyl chitosan. These macromolecules are all polysaccharide derivatives with carboxyl functional groups, which carry a negative charge after ionization in aqueous solution, enabling them to migrate directionally under the action of an electric field. Furthermore, these macromolecules have excellent cross-linking and gelling capabilities with divalent or polyvalent metal ions subsequently released at the anode. By controlling the mass concentration of these macromolecules in the electrophoretic modification solution within the range of 0.5% to 2.0%, a suitable viscosity can be ensured. This guarantees a sufficient concentration of macromolecules in the solution for subsequent gelation reactions while avoiding excessive viscosity that would increase the fluid resistance to macromolecule migration within the fiber network. Therefore, the selection and concentration control of the above-mentioned raw materials lay the material foundation for the efficient and stable electrochemical gelation process, ensuring that the final material possesses both good mechanical properties and gelation function.

[0015] Preferably, the soluble metal anode in step 3 is a pure calcium plate, pure zinc plate, or pure magnesium plate, and the inert cathode is a graphite plate, platinum plate, or titanium plate; and the DC voltage applied in step 4 is 5V to 50V. It can be understood that the soluble metal anode in step 3 specifically uses a pure calcium plate, pure zinc plate, or pure magnesium plate, while the inert cathode uses a chemically stable graphite plate, platinum plate, or titanium plate. Calcium, zinc, and magnesium are chosen as anode materials because these metals have low electrochemical potentials, can undergo stable oxidation reactions under moderate voltages, and the generated Ca... 2+ Zn 2+ Mg 2+All ions used are known biocompatible ions capable of effectively cross-linking with macromolecular anions such as alginate. Graphite, platinum, or titanium are chosen as cathodes because they are chemically stable during electrolysis and do not participate in the reaction, ensuring the specificity of the electrochemical process; that is, the reaction is mainly concentrated at the anode interface. Simultaneously, the DC voltage applied in step 4 is controlled within the range of 5V to 50V. This voltage range is sufficient to provide the overpotential required to drive the electrophoretic migration of macromolecules and the electrochemical dissolution of the anode metal, ensuring the effective progress of the reaction; at the same time, this voltage is not too high, which could trigger violent water electrolysis or other side reactions, thus ensuring efficient energy utilization and process safety. This technical solution, through the optimized selection of electrode materials and operating voltage, constructs a highly efficient, stable, and specific electrochemical reaction system, providing a reliable process guarantee for the controllable release of cross-linked ions and the effective penetration of macromolecules.

[0016] Preferably, in step 4, the total amount of cross-linked ions released from the anode dissolution is quantitatively controlled by controlling the energizing time or the total charge, thereby achieving precise control over the total amount of gel generated. Specifically, in this scheme, the electrochemical treatment process in step 4 quantitatively controls the total amount of cross-linked ions released from the anode dissolution by controlling the energizing time or the total charge. According to Faraday's law of electrolysis, the amount of substance generated in the electrode reaction is strictly proportional to the total charge passing through the electrolytic cell. The total charge is the product of current and time, and this physical quantity can be precisely set and monitored using modern DC power supplies. Therefore, by pre-setting a precise energizing time (in constant voltage or constant current mode) or a precise total charge, the amount of anode metal undergoing the electrochemical oxidation reaction can be quantitatively controlled, thereby precisely controlling the total number of cross-linked ions released to the reaction interface. Since the subsequent cross-linking reaction is instantaneous and efficient, the total amount of gel generated directly depends on the total amount of cross-linked ions. This method transforms the gel formation process from a traditional, diffusion- and equilibrium-dependent, and quantitatively difficult-to-control wet chemical process into an electrochemical process precisely controlled by electrical charge. This quantitative control method based on electrical charge measurement allows the gel loading in the final product to be precisely preset and achieved, thereby ensuring high uniformity of product performance and batch-to-batch stability, and solving the technical problem of unstable product performance caused by fluctuations in process parameters in traditional methods.

[0017] Preferably, to further improve the penetration depth and uniformity of the modifier in the substrate, the soluble metal anode in step 3 is an alloy anode composed of at least two biocompatible metals. When a DC voltage is applied in step 4, the different metal components in the alloy anode undergo competitive oxidative dissolution, simultaneously releasing multiple metal ions as composite crosslinking agents to react with the biocompatible macromolecules and form a gel network with composite functions. Specifically, in this scheme, the soluble metal anode in step 3 is an alloy anode composed of at least two biocompatible metals. When a DC voltage is applied in step 4, due to the differences in the standard electrode potential and activity of different metal components in the alloy, they undergo competitive electrochemical oxidative dissolution, thereby simultaneously and synergistically releasing multiple metal ions from the anode surface. For example, using a calcium-zinc alloy as the anode, under the action of an electric field, Ca... 2+ and Zn 2+ Ions simultaneously enter the adjacent spunlace nonwoven fabric. These mixed metal ions act as composite cross-linking agents, reacting with the biocompatible macromolecules that have migrated there. Among them, the main component ions (such as Ca) 2+ The primary component ions (such as Zn) function to form the basic gel network framework, giving the material its main gel texture and moisturizing properties; while secondary component ions (such as Zn) play a crucial role. 2+ These components, either as cross-linking points or in the form of trapped ions, are uniformly embedded in the gel network, endowing the material with additional bioactivity, such as antibacterial and oil-controlling properties. This approach achieves one-step preparation of composite functional gel-modified materials in the same process step by simply replacing the anode, a single raw material. Compared to traditional multi-step impregnation or functional finishing processes, this method greatly simplifies the production process, reduces costs, and ensures uniform distribution of different functional components at the microscale in the material, thereby obtaining functionalized nonwoven materials with higher performance integration.

[0018] Preferably, to further improve the penetration depth and uniformity of the modifier in the substrate, a pretreatment step is included before step 3: the spunlace nonwoven fabric is placed as a diaphragm in a pretreatment solution containing inorganic salts with small molecule polyvalent anions, and a DC electric field is applied to this system, causing the small molecule polyvalent anions to adsorb onto the fiber surface as precursor ions, thereby optimizing the charge environment on the fiber surface; the inorganic salt containing the small molecule polyvalent anions is sodium citrate or sodium tripolyphosphate. Specifically, this scheme adds a pretreatment step before step 3, that is, the spunlace nonwoven fabric is placed in a pretreatment solution containing inorganic salts with small molecules and polyvalent anions (such as sodium citrate or sodium tripolyphosphate), and a brief DC electric field is applied. The technical principle is that the surface of natural cellulose fibers and the subsequent migrating macromolecular modifiers (such as alginate) both carry negative charges, and the electrostatic repulsion between the two will hinder the macromolecules from penetrating deep into the fiber network. In this pretreatment step, small, fast-migrating polyvalent anions such as citrate or phosphate can act as "vanguard" under the influence of an electric field, rapidly migrating and preferentially adsorbing onto the surface of cellulose fibers. This adsorption effectively optimizes the charge environment on the fiber surface, forming a uniform negative charge shielding layer, thereby significantly reducing the long-range electrostatic repulsion between the fibers and subsequently migrating macromolecules. This is equivalent to removing some electrostatic barriers for the penetration of the large-volume "main force," opening up a smoother migration path. Therefore, in the subsequent main electrochemical gelation step, biocompatible macromolecules can penetrate more quickly, deeply, and uniformly into the entire thickness space of the nonwoven fabric, resulting in a more uniform distribution of the final gel network across the entire cross-section from the surface to the core. This ultra-uniform gel distribution directly translates into a finer, more uniform macroscopic feel in the final product, as well as improved mechanical properties (such as toughness) due to reduced internal structural defects.

[0019] Preferably, to achieve precise functional zoning of the product and meet more advanced customization needs, the soluble metal anode in step 3 is a composite functional anode plate, which is spliced ​​together from at least two different pure metal sheets according to a preset pattern corresponding to the facial care zones. In step 4, different metal regions of the anode plate release different cross-linked ions in situ, thereby forming a gel of chemical components and functional zones at corresponding positions on the spunlace nonwoven fabric. Specifically, in this scheme, the soluble metal anode in step 3 is no longer a homogeneous metal plate, but a composite functional anode plate spliced ​​together from at least two different pure metal sheets according to a preset pattern corresponding to the facial care zones (such as T-zone and U-zone). During the electrochemical treatment in step 4, since the electric field lines are approximately perpendicular to the electrode surface within a small distance between the electrode and the substrate, the release and migration of ions are highly localized. This means that above different metal regions of the composite anode plate, corresponding electrochemical dissolution will occur independently, releasing cross-linked ions corresponding to the metal material of that region in situ. For example, in the zinc sheet region corresponding to the facial T-zone, Zn will be mainly released. 2+ Ions; while in the calcium-rich areas corresponding to the U-zone of the face, primarily Ca2+ is released. 2+ Ions. These cross-linked ions, released in the partitioned areas, cross-link with macromolecules such as alginate that migrate to the corresponding regions, thereby precisely replicating the functionalized gel partitions on the spunlace nonwoven fabric in a 1:1 ratio with the anode pattern. The resulting single nonwoven material sheet naturally possesses different chemical compositions and skincare benefits in different areas (e.g., oil control in the T-zone, moisturizing in the U-zone). This method eliminates the need for complex overprinting, spraying, or multi-step processing. By designing a special anode plate, it efficiently manufactures "intelligent partitioned care" products that perfectly match specific skincare needs in a single process step, providing significant flexibility and added value for the functional design of nonwoven materials.

[0020] Preferably, to achieve targeted functional enhancement in specific areas of the material, a targeted functional preloading step is included before step 2: using a micro-nozzle or stamp-like tool, a concentrated solution containing microcapsules or liposomes encapsulating skin-care active ingredients is precisely applied to a specific area of ​​the spunlace nonwoven fabric by dotting or printing; in step 4, the generated gel network anchors and embeds the pre-applied microcapsules or liposomes in situ. Specifically, this scheme adds a targeted functional preloading step before step 2, that is, using precise application methods such as micro-nozzles or stamp-like tools, a concentrated solution containing microcapsules or liposomes encapsulating skin-care active ingredients is precisely applied to a specific area of ​​the spunlace nonwoven fabric by dotting or printing. These microcapsules or liposomes can be functional carriers encapsulating active substances such as vitamin C and retinol. After completing this preloading step, the subsequent electrochemical gelation main process is carried out. The technical logic lies in cleverly utilizing the gel network formation process in subsequent step 4 to fix these passively pre-placed functional components. When cross-linked ions released from the anode react in situ with migrating biocompatible macromolecules within the fiber network to form a three-dimensional gel network, this emerging network structure physically anchors and encapsulates functional carriers such as microcapsules or liposomes pre-placed between the fibers. This in-situ encapsulation mechanism effectively protects the encapsulated active ingredients, preventing premature degradation or inactivation due to exposure during storage and initial use. Furthermore, the formed gel network also constitutes a sustained-release barrier, allowing these highly effective ingredients to be slowly and continuously released from the designated area during use, acting on the target skin, thereby improving the bioavailability of the active ingredients and potentially reducing their potential irritation. This approach, without altering the main manufacturing process, achieves the superimposed application of multiple highly customized localized potent functions to the product through a simple pretreatment step, significantly enhancing the product's technological content and personalized service capabilities.

[0021] Preferably, the soluble metal anode in step 3 is a layered composite anode, which is formed by laminating at least two different metal foils or sheets. In step 4, the electrochemical reaction starts from the outermost metal layer. When the outer metal layer is exhausted, the inner metal layer is automatically exposed and takes over the reaction, thereby sequentially depositing a multilayered functional gel on the spunlace nonwoven fabric. Specifically, in this scheme, the soluble metal anode in step 3 is a layered composite anode, which is formed by laminating at least two different metal foils or sheets. For example, a thin zinc foil is tightly laminated onto the surface of a thicker calcium plate, with the zinc foil layer facing the spunlace nonwoven fabric. The technical principle lies in utilizing the electrochemical reaction sequence of different metals. After applying voltage in step 4, the electrochemical reaction preferentially starts from the outermost metal layer, which is in direct contact with the electrolyte. Therefore, the outer zinc foil layer will be electrochemically dissolved first, releasing Zn. 2+Ions form a thin gel layer with antibacterial and oil-controlling functions on the substrate layer closely adhering to the fibers. As the reaction proceeds, once the outer zinc foil is completely consumed, the inner calcium plate is automatically exposed, becoming a new reaction interface and initiating electrochemical dissolution, releasing Ca. 2+ Ions. These Ca 2+ Ions will continue to build a main gel structure on top of the already formed zinc gel layer, primarily for moisturizing and water-locking functions. This method cleverly integrates complex programmed control processes, such as step-by-step feeding or programmed voltage regulation, into the structural design of an anode plate. Operators only need to apply a single, continuous current to automatically and sequentially prepare nonwoven materials with ordered multilayer functional structures (e.g., "inner antibacterial layer + outer moisturizing layer"). This process is extremely simple, stable, and reliable, yet the resulting product structure is highly functional and precise, providing a feasible path for the low-cost, large-scale production of advanced materials.

[0022] Preferably, to improve the liquid transport efficiency within the material, an implementation method for achieving self-construction of a microchannel network within the material includes a sacrificial structure embedding step before step 2: fibers or slurries composed of water-soluble polymer materials are applied or embedded into the spunlace nonwoven fabric according to a preset network pattern; in step 4, a gel network is formed and the sacrificial structure is embedded; during the rinsing process in step 5, the water-soluble polymer material is dissolved and removed, thereby forming in-situ interconnected hollow microfluidic channels consistent with the preset network pattern within the gelled material; the water-soluble polymer material is polyvinyl alcohol; the sacrificial structure is applied to the surface or interior of the spunlace nonwoven fabric using 3D printing or micro-dispensing technology. Specifically, this scheme adds a sacrificial structure embedding step before step 2, that is, using 3D printing or micro-dispensing technology, fibers or slurries composed of water-soluble polymer materials (such as polyvinyl alcohol) are applied or embedded into the spunlace nonwoven fabric according to a preset network pattern such as leaf veins. In step 4, a gel network forms and completely encapsulates these sacrificial structures. The key to this process lies in step 5, the rinsing stage. When the gelled material comes into contact with water, the encapsulated water-soluble sacrificial structures, such as polyvinyl alcohol, dissolve rapidly and are carried away by the water flow. Because the surrounding gel network has already cross-linked and solidified, possessing a stable three-dimensional structure, the spaces left after the sacrificial structures dissolve do not collapse. Instead, they spontaneously and in situ form interconnected hollow microfluidic channels that perfectly match the pre-designed pattern. These internal microchannels constitute a "highway" for liquids (such as serums), greatly accelerating the transport and diffusion of liquids within the material, allowing them to reach every corner of the material faster and more evenly. This two-stage transport mechanism of "rapid dispensing + slow absorption" significantly shortens the liquid's immersion time, ensuring uniform immersion and thus improving user experience and the utilization efficiency of active ingredients. The channel formation process is "spontaneous," requiring no additional etching or removal steps; it can be completed only during the routine cleaning process, resulting in high process integration and strong controllability.

[0023] Preferably, the electrophoretic modification solution in step 2 further disperses photosensitive semiconductor nanoparticles; the soluble metal anode in step 3 is replaced with a transparent conductive electrode; and in step 4, a preset illumination pattern is projected onto the non-contact surface of the transparent conductive electrode using a digital projector or a light source with a mask, selectively activating the electrochemical reaction in the illuminated area, thereby forming a patterned gel region corresponding to the illumination pattern on the spunlace nonwoven fabric. Specifically, this scheme adjusts the apparatus and raw materials: photosensitive semiconductor nanoparticles (such as nano-titanium dioxide) are additionally dispersed in the electrophoretic modification solution in step 2; the soluble metal anode in step 3 is replaced with a transparent conductive electrode (such as ITO glass). The core lies in the execution method of step 4: a preset illumination pattern is projected onto the non-contact surface of the transparent conductive electrode using a digital projector or a light source with a mask. Its technical principle is the photoelectrochemical catalytic effect. Without illumination, the catalytic activity of semiconductor nanoparticles is very low. However, when exposed to light of a specific wavelength, it generates highly oxidizing photogenerated holes, which greatly catalyze and accelerate the electrochemical reactions occurring on the adjacent anode surface, thereby "activating" the electric field strength and reaction rate in that region. Therefore, only in the illuminated areas is the electrochemical reaction significantly enhanced, efficiently driving macromolecular migration and cross-linking with pre-added cross-linking ions in the solution, while the reaction rate in the unilluminated "dark" areas is extremely slow. This scheme cleverly shifts the core control factor from "electricity" to "light." By changing the projected digital light pattern, the position, shape, and size of the gel formation can be altered in real time and non-contactly, with precision down to the micrometer level, without the need for any physical molds. The entire manufacturing process is fully computer-controlled, providing technological possibilities for personalized customization of functional areas and rapid product iteration. Even by adjusting the grayscale of the projected light intensity, complex functional areas with gradient changes in gel density can be formed on the material, representing an extremely high technological ceiling.

[0024] The technical effects achievable by the method for preparing modified cellulose fiber nonwoven material for ice crystal films according to the present invention include:

[0025] First, the electrochemical in-situ gelation reaction replaces the traditional wet chemical route of "alkali swelling-padding-acid / salt treatment-washing." The entire process eliminates the need for strong acids and alkalis, preventing the generation of acid and alkaline wastewater at the source, significantly simplifying the process, and reducing energy consumption and environmental treatment costs. Second, the active penetration of charged macromolecules using an electric field, compared to passive mechanical padding, enables a deeper and more uniform distribution of the modifier along the thickness of the nonwoven fabric. Simultaneously, crosslinking ions are generated in situ at the reaction interface and react instantly with the macromolecules enriched there, forming efficient in-situ solidification, ensuring a high fixation rate of the gel in the material, thereby improving the product's performance stability. Furthermore, the entire modification process is carried out in a mild, neutral electrolyte environment, avoiding damage to the cellulose molecular chains from high-concentration chemicals and perfectly protecting the original mechanical properties of the substrate. Furthermore, because the fiber density is lower in the "valleys" (line areas) of the spunlace fabric's three-dimensional texture, the local resistance formed in the electrolyte is lower than that in the "peaks" (solid surfaces). Under constant voltage conditions, current preferentially flows through the low-resistance areas, resulting in a relatively higher anodic dissolution and gel deposition rate in the "valleys." This differentiated deposition effect is equivalent to a precise chemical "outlining" and reinforcement of the original physical texture, making the three-dimensional texture of the final product clearer and more distinct, thus improving the product's appearance and recognizability. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of the basic electrochemical reaction device of the present invention;

[0028] Figure 2 This is a schematic diagram of the texture enhancement mechanism of the present invention;

[0029] Figure 3 This is a schematic diagram (top view of the anode plate) of the anode structure of the functional nursing material for zoned use in this invention;

[0030] Figure 4 It is about Figure 3 A cross-sectional view of the anode plate in its working state;

[0031] Figure 5 This is a schematic diagram of the layered anode structure of the sequential functional layered membrane of the present invention (initial layered anode structure);

[0032] Figure 6This is a schematic diagram of the layered anode structure of the sequential functional layered membrane of the present invention (layered anode structure after outer layer consumption);

[0033] Figure 7 This is a schematic diagram of the formation process of self-constructed microfluidic channels according to the present invention;

[0034] Figure 8 This is a schematic diagram of the photoelectrochemical customized preparation device of the present invention.

[0035] Figure label:

[0036] none. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below in conjunction with specific embodiments. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention. Unless otherwise stated, the reagents used in each embodiment are commercially available analytical grade or higher products, and the equipment used is conventional experimental equipment in the art.

[0038] Example 1

[0039] This embodiment aims to illustrate the basic preparation method of a modified cellulose fiber nonwoven material according to the present invention. The specific steps are as follows:

[0040] The first stage involves the preparation of a cellulose fiber spunlace nonwoven fabric with a three-dimensional texture. 100% Lyocell fiber with a denier of 1.5 dtex and a length of 38 mm is selected as the raw material. The fiber is fed into an opening machine for thorough opening, followed by carding in a carding machine to form a fabric with a basis weight of 45 g / m². 2 A uniform fiber web is formed. This fiber web is laid flat on a screen with a precisely engraved array of diamond-shaped protrusions. The protrusions on the screen are 0.5 mm high, and the diagonal lengths of the diamonds are 3 mm and 5 mm, respectively, forming the preset three-dimensional texture pattern. Subsequently, the fiber web is reinforced by hydroentangling using multiple hydroentangling heads. The hydroentangling pressure is set in an increasing mode: 30 bar for the first hydroentangling head, 60 bar for the second, and 100 bar for the third and fourth. The energy of the high-pressure water jet causes the fibers to shift, interweave, and entangle, thereby reinforcing the fabric and precisely replicating the diamond-patterned texture of the screen during this process, forming a semi-finished hydroentangled nonwoven fabric with a clear three-dimensional texture. The fabric is then subjected to preliminary dehydration and pre-drying treatment before use.

[0041] The second stage is post-electrochemical gelation finishing. First, an electrophoretic modification solution is prepared. 100g of food-grade sodium alginate (1% aqueous solution with a viscosity of 200 mPa·s at 20℃) is weighed and slowly added to 9900g of deionized water. The solution is stirred at low speed with a magnetic stirrer at room temperature for 4 hours until completely dissolved, forming a homogeneous and transparent electrophoretic modification solution with a mass concentration of 1.0%. The pH of this solution is approximately 6.8-7.2, indicating neutrality. Subsequently, an electrochemical reaction apparatus is constructed, such as… Figure 1 As shown, in an electrolytic cell measuring 30cm × 40cm, a pure calcium (Ca) metal plate (purity ≥ 99.9%) with a matching size and a thickness of 2mm is used as the soluble metal anode, and a high-purity graphite plate with the same size and a thickness of 5mm is used as the inert cathode. The spunlace nonwoven fabric prepared in the first stage is used as a porous membrane, smoothly and without wrinkles, tightly attached to the surface of the calcium plate anode. The graphite cathode is then placed parallel to each other, maintaining a distance of 2.0cm between the two electrodes, and fixed with insulating clamps to form the core of the electrolytic cell. The assembled electrolytic cell is completely immersed in the sodium alginate electrophoretic modification solution described above. A DC regulated power supply is connected, with the calcium plate connected to the positive electrode and the graphite plate to the negative electrode, applying a constant DC voltage of 20V and controlling the energizing time to be 180 seconds. During this process, negatively charged alginate macromolecules (Alg-COO-) in the solution migrate at high speed towards the anode under the drive of the electric field and penetrate the porous structure of the spunlace fabric, reaching deep into its interior. At the same time, an electrochemical oxidation reaction occurs at the calcium anode: Ca → Ca 2+ +2e - At the interface immediately adjacent to the spunlace fabric, calcium ions (Ca) of the cross-linking agent are continuously released in situ. 2+ Alginate ions that migrate to the anode interface immediately undergo a complexation and cross-linking reaction with freshly generated calcium ions to form a water-insoluble calcium alginate gel: 2(Alg-COO) - )+Ca 2+ →(Alg-COO)2Ca, thus firmly fixing alginate within the fiber network. According to Faraday's law of electrolysis, the total amount of calcium ions dissolved at the anode is proportional to the total charge passing through (the product of current and time). Therefore, by precisely controlling the energizing time to 180 seconds, the total amount of gel generated can be quantitatively controlled, ensuring the uniformity of product performance and batch stability. After reaching the preset time, the power is turned off, and the modified spunlace fabric, which has exhibited a distinct gel texture, is removed. It is then gently rinsed in flowing deionized water for 60 seconds to remove residual electrolytes from the surface, and then dried in a 70°C hot air oven until the moisture content is below 8%, thus obtaining the final product, the final ice crystal film.

[0042] The material prepared in this embodiment achieves a higher gel fixation rate due to the active and deep penetration of the modifier via electrophoresis and the immediate locking effect achieved through in-situ electrochemical crosslinking. Simultaneously, the formed calcium alginate gel endows the material with excellent water-locking properties, with a water retention rate exceeding 50 times its own dry weight. More importantly, this method utilizes the differences in electrical properties caused by the texture of the spunlace fabric itself. The "valleys" (line areas) of the ice-diamond texture have lower local resistance due to their lower fiber density and thinner thickness, while the "peaks" (rhomboid surfaces) have the opposite. Under constant voltage, current preferentially flows through the low-resistance "valleys," resulting in a higher current density in this region, a faster anodic dissolution rate, and the release of Ca. 2+ The presence of more ions allows the gel to deposit more thickly in the "valley" region; the mechanism can be found in [reference needed]. Figure 2 As shown. This differentiated gel deposition effect chemically "outlines" and reinforces the physical texture, making the texture of the final product clearer, deeper, and more three-dimensional than the original spunlace fabric, thus enhancing the product's appearance and texture.

[0043] Example 2

[0044] The preparation process in this embodiment is basically the same as in Example 1, with the key difference being the construction of the electrochemical reaction device in the second stage. The anode is no longer a pure calcium plate, but a calcium-zinc (Ca-Zn) alloy plate prepared by powder metallurgy, wherein the mass ratio of calcium to zinc is Ca:Zn = 98:2. The remaining device configuration (cathode, spacing, etc.) and operating parameters (1.0% sodium alginate solution, constant DC voltage of 25V, processing time of 180 seconds) remain unchanged.

[0045] In the electrochemical treatment process of this embodiment, after the power is turned on, the alloy anode undergoes electrochemical dissolution. Because calcium is more chemically reactive than zinc, calcium preferentially oxidizes: Ca → Ca 2+ +2e - Simultaneously, the applied 25V voltage provides a sufficiently large overpotential, allowing zinc to oxidize effectively: Zn → Zn 2+ +2e - Therefore, calcium and zinc ions are simultaneously released from the anode surface, acting as a composite crosslinking agent and entering the adjacent spunlace fabric. The released Ca... 2+ Ions act as the main cross-linking agent, forming a stable gel framework network with alginate, thus imparting the material with its primary moisturizing properties and gel texture. Simultaneously, the released Zn... 2+ Some of the ions also participated in the cross-linking with alginate, while others were uniformly captured and fixed in the calcium alginate gel network in ionic form or in situ generated zinc hydroxide particles.

[0046] This embodiment integrates moisturizing (derived from calcium alginate gel) and antibacterial and oil-controlling (derived from zinc ions, known for their broad-spectrum antibacterial, anti-inflammatory, pore-tightening, and sebum-regulating effects) functions into a single ice crystal film using a one-step method. Testing revealed that the finished material contains a uniformly distributed zinc content of approximately 0.1% (w / w) and exhibits significant antibacterial effects against Staphylococcus aureus and Propionibacterium acnes. This approach simplifies the process and ensures uniform distribution of functional components at the microscale by simply replacing the anode material, thus producing a multi-functional composite material in a single process step.

[0047] Example 3

[0048] This embodiment, based on the process of Example 1, adds an ion pretreatment step before the second-stage electrochemical gelation finishing. Specifically, a 0.2% (w / w) trisodium citrate aqueous solution is first prepared as the pretreatment solution. The spunlace nonwoven fabric obtained in the first stage of Example 1 is immersed in this pretreatment solution, using the same electrode configuration as the main reaction (pure calcium plate as the anode and graphite plate as the cathode), and a 10V DC voltage is applied for 45 seconds. During this process, the small, fast-migrating citrate ions act as the "vanguard," rapidly migrating and adsorbing onto the surface of the cellulose fibers under the influence of the electric field. After the pretreatment is completed, the still-wet spunlace fabric is removed and, without drying, directly transferred to the 1.0% sodium alginate electrophoretic modification solution described in Example 1 for the same electrochemical main reaction treatment as in Example 1 (pure calcium anode, 20V, 180 seconds), followed by rinsing and drying.

[0049] The technical effect stems from the optimization of the surface charge environment of the fibers. Both natural cellulose fibers and alginate macromolecules are negatively charged in aqueous solution, exhibiting electrostatic repulsion and hindering the macromolecules from penetrating deeper into the fiber network. The citrate ions adsorbed on the fiber surface during the pretreatment step effectively form a uniform negatively charged "shielding layer," reducing the long-range electrostatic repulsion between the fibers and subsequently migrating alginate macromolecules, thus opening a smoother penetration path for the macromolecules. Therefore, in the main reaction, alginate can be distributed more quickly, deeply, and uniformly throughout the thickness of the nonwoven fabric. Observing the cross-section of the material using a confocal laser scanning microscope reveals that the fluorescently labeled gel in the material prepared in this embodiment is extremely uniformly distributed along the entire thickness direction from the surface to the core, while the untreated sample is mainly enriched in the surface layer. This highly uniform gel distribution results in a more delicate and uniform macroscopic feel to the material prepared in this embodiment, free of hard or weak points, and its elongation at break is increased by approximately 15% compared to Example 1, exhibiting better toughness.

[0050] Example 4

[0051] The key improvement in this embodiment lies in the anode design of the second-stage electrochemical reaction device. Combined with... Figure 3 and Figure 4 As shown, the anode uses a "composite functional anode plate," which is based on an insulating epoxy resin board. Following the contours of a standard adult face, different metal sheets are precisely inlaid into a specific pattern. Specifically, pure zinc (Zn) metal sheets are used as the anode active area corresponding to the T-zone (forehead and nose); pure calcium (Ca) metal sheets are used as the anode active area corresponding to the U-zone (cheeks). All metal areas are flush, forming a coplanar anode working surface, and are connected to the positive terminal of the power supply via parallel wires on the back. Spunlace fabric is precisely aligned and covered onto the composite functional anode plate, followed by electrochemical treatment (1.0% sodium alginate solution, 30V constant DC voltage, treatment for 180 seconds).

[0052] Upon energization, electrochemical dissolution occurs simultaneously in different metal regions of the anode plate, and the release and migration of ions exhibit high locality. Therefore, in region T, the released Zn... 2+ Ions crosslink with the alginate groups that migrate to this area, forming a zinc-rich gel at the corresponding locations on the spunlace fabric, thus endowing this region with oil-controlling and antibacterial functions; in the U region, released Ca... 2+ Ions then form calcium-rich gels at corresponding locations, providing those areas with powerful moisturizing properties. Ultimately, the chemical composition and function of different areas on the spunlace fabric precisely replicate the metallic pattern of the anode plate. X-ray fluorescence spectroscopy surface scanning analysis of the finished product clearly shows that the T-zones are enriched with zinc, while the U-zones are enriched with calcium, perfectly matching the anode design with clear zoning boundaries. This embodiment eliminates the need for complex overprinting or multi-step processing; by designing a single special anode plate, an integrated functional material capable of precise zoning care for combination skin and other skin types is manufactured in a single process step.

[0053] Example 5

[0054] This embodiment, based on the process of Example 1, adds a targeted functional preloading step before the second-stage electrochemical gelation finishing process. Liposomes encapsulated with retinol are selected and prepared into a highly concentrated dispersion. Using a micro-dispensing machine, this concentrated dispersion is precisely "printed" onto the spunlace nonwoven fabric in a 1mm diameter dot matrix pattern, targeting areas of the face prone to wrinkles (such as the corners of the eyes and forehead). After preloading, this fabric is used in the subsequent main electrochemical gelation process, with the specific operation exactly the same as in Example 1 (1.0% sodium alginate solution, pure calcium anode, 20V, 180 seconds).

[0055] During the electrochemical treatment, the forming calcium alginate gel network physically embeds and fixes the retinol liposomes pre-placed between the fibers. This in-situ embedding provides effective physical protection for the environmentally sensitive retinol, preventing its deactivation due to exposure to air and light during storage and initial use. Simultaneously, the dense gel network also acts as a slow-release barrier, allowing retinol to be released slowly and continuously from the designated area during use, improving its efficiency on the target skin and reducing potential irritation. This embodiment, through a simple pretreatment step, flexibly adds a powerful local anti-wrinkle function to the product, greatly expanding the product's customizability.

[0056] Example 6

[0057] The preparation process in this embodiment is basically the same as in Example 1, with the key difference being the structure of the anode. Figure 5 and Figure 6 As shown, the anode is a layered composite anode, which is constructed by tightly laminating a 20 μm thick pure zinc (Zn) foil onto the surface of a 2 mm thick pure calcium (Ca) plate, with the zinc foil layer facing the spunlace nonwoven fabric. The electrochemical treatment parameters were set as follows: 1.0% sodium alginate solution, 22 V constant DC voltage, and treatment time of 240 seconds.

[0058] The electrochemical reaction preferentially begins with the outermost zinc foil. In the initial stages of the process, the zinc foil is electrochemically dissolved, releasing Zn. 2+ Ions form a thin, zinc-rich gel layer, primarily for antibacterial and oil-controlling purposes, on the substrate layer tightly adhering to the fibers. As the reaction proceeds, once the outer zinc foil is completely consumed (e.g., after approximately 60 seconds), the inner calcium plate is automatically exposed, becoming the new reaction interface. At this point, the calcium plate begins to dissolve electrochemically, releasing Ca2+. 2+ Ions continue to build a thicker, calcium-rich gel structure on top of the already formed zinc gel layer, which is mainly for moisturizing and locking in moisture.

[0059] This embodiment simplifies the complex "step-by-step feeding" or "programmed voltage control" process into a single continuous operation through the structural design of the anode itself. The operator only needs to continuously apply electricity for a sufficiently long time to automatically prepare a mask material with an ordered dual-layer functional structure of "inner antibacterial layer + outer moisturizing layer." This process is simple and reliable to control, yet the resulting product structure is highly functional and precise, making it an ideal way to achieve low-cost, large-scale production of advanced materials.

[0060] Example 7

[0061] This embodiment, based on the process of Embodiment 1, adds a pre-set template step before the second stage. For example... Figure 7As shown, a 20% (w / w) aqueous solution of polyvinyl alcohol (PVA, model 17-88, easily soluble in warm water) was first prepared and heated to 90°C to completely dissolve it. The solution was then cooled to room temperature to form a high-viscosity slurry. Using a triaxial micro-dispensing machine, the PVA slurry was printed onto the surface of the spunlace fabric in a pre-designed leaf vein network pattern with lines of 200 μm in diameter, forming a soluble template. The fabric was then briefly dried at 60°C to solidify and adhere the PVA lines. The spunlace fabric with the PVA template was then subjected to the same electrochemical treatment as in Example 1 (1.0% sodium alginate solution, pure calcium anode, 20V, 180 seconds), during which calcium alginate gel formed and completely embedded the PVA template. The key to this method lies in the final post-treatment step. The modified spunlace fabric was removed and rinsed directly in warm water at 40°C. The PVA template embedded in the gel dissolves rapidly and is carried away by the water flow. Since the surrounding gel network has solidified, the space left after the PVA dissolves will not collapse, thus forming in situ, spontaneously interconnected hollow microfluidic channels that are consistent with the printed pattern.

[0062] Scanning electron microscopy revealed clearly defined hollow circular channels in the cross-section of the finished product. These microchannels significantly enhance the transport efficiency of liquids such as serums. In the permeation rate test, a simulated serum with added dye rapidly diffused along the pre-designed channel network on the membrane of this embodiment, uniformly wetting the entire membrane within 10 seconds, while the membrane of Example 1 required more than 60 seconds. This clearly demonstrates the significant improvement in liquid transport efficiency brought about by the constructed microfluidic channels, thus enhancing the user experience.

[0063] Example 8

[0064] This embodiment modifies the apparatus and raw materials. (See reference...) Figure 8 As shown, the electrophoretic modification solution was prepared as follows: 0.5% (w / w) of calcium chloride was added to the 1.0% sodium alginate solution in Example 1 as a pre-set crosslinking ion source, and 0.05% (w / w) of food-grade nano-titanium dioxide (TiO2) was dispersed as photosensitive semiconductor nanoparticles. The anode of the electrochemical device was a transparent conductive ITO glass. A digital projector was installed outside the device, enabling it to accurately project a preset illumination pattern onto the back side of the ITO glass anode (the side not in contact with the spunlace fabric). During electrochemical treatment, a low DC bias voltage (e.g., 3V) was applied, and a "cross-shaped" illumination pattern was projected onto the anode using 365nm ultraviolet light through the digital projector for 300 seconds.

[0065] The underlying technology lies in photoelectrochemical catalysis. Without illumination, a low bias voltage of 3V is insufficient to trigger a significant electrochemical reaction. However, when ultraviolet light irradiates TiO2 nanoparticles, it generates highly oxidizing photogenerated holes. These holes significantly catalyze electrochemical reactions (such as the oxidation of water molecules) occurring on the adjacent ITO anode surface, thereby "activating" the electric field strength and reaction rate in the illuminated area. Therefore, only the anode area illuminated by the "cross-shaped" light pattern experiences a significantly enhanced electrochemical reaction, efficiently driving the migration of alginate ions and their reaction with pre-placed Ca in the solution. 2+ Cross-linking occurs. In the "dark" areas that are not exposed to light, the reaction rate is extremely slow, and almost no gel forms.

[0066] The resulting nonwoven material exhibits a clearly defined "cross-shaped" gel area that matches the projected pattern. This embodiment allows for real-time, zero-delay modification of the gel's position, shape, and size by altering the projected digital pattern, achieving micron-level precision without the need for physical molds. The entire manufacturing process is fully computer-controlled, providing a novel technological approach for instant, personalized customization of functional areas and rapid iterative product development.

[0067] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for producing a modified cellulose fiber nonwoven material for ice crystal films, characterized by, Includes the following steps: Step 1: Select cellulose fibers and make them into a fiber web by opening and combing. Lay the fiber web on a web-forming curtain with a preset three-dimensional texture pattern. Use multiple high-pressure water jets to vertically impact the fiber web to perform hydroentanglement reinforcement, causing the fibers to entangle and replicate the three-dimensional texture pattern of the web-forming curtain, forming a cellulose fiber hydroentangled nonwoven fabric with a three-dimensional texture. Step 2: Dissolve the negatively charged biocompatible macromolecules in deionized water to prepare an electrophoretic modification solution; Step 3: The spunlace nonwoven fabric obtained in Step 1 is used as a porous membrane and is flat and wrinkle-free and tightly attached to the surface of the soluble metal anode. Then, the inert cathode is placed in parallel so that the distance between the two electrodes is kept at 2.0 cm and fixed with insulating clamps to form the core of the electrolytic cell. Step 4: Immerse the electrolytic cell in the electrophoretic modification solution prepared in Step 2, apply a DC voltage between the two electrodes, and cause the negatively charged biocompatible macromolecules to migrate towards the anode and penetrate into the interior of the spunlace nonwoven fabric under the drive of the electric field. At the same time, the soluble metal anode undergoes an electrochemical oxidation reaction to release cross-linking ions in situ. The migrated macromolecules react with the released cross-linking ions to form a gel network. Step 5: Stop the power supply, take out the modified spunlace nonwoven fabric, rinse it with deionized water and dry it to obtain the modified cellulose fiber nonwoven material.

2. The method of producing a modified cellulose fiber nonwoven material for ice crystal films according to claim 1, characterized by, The cellulose fiber in step 1 is selected from at least one of lyocell fiber, cuprammonium fiber, viscose fiber or cotton fiber; and the negatively charged biocompatible macromolecule in step 2 is sodium alginate, sodium hyaluronate or carboxymethyl chitosan, and its mass concentration in the electrophoretic modification solution is 0.5% to 2.0%.

3. The method of claim 1, wherein the modified cellulose fiber nonwoven material for ice crystal film is characterized by, In step 3, the soluble metal anode is a pure calcium plate, a pure zinc plate, or a pure magnesium plate, and the inert cathode is a graphite plate, a platinum plate, or a titanium plate; and in step 4, the applied DC voltage is 5V to 50V.

4. The method of producing a modified cellulose fiber nonwoven material for ice crystal films according to claim 3, characterized by, In step 4, the total amount of crosslinked ions released from the anode by controlling the energizing time or the total charge is quantitatively controlled, thereby achieving precise control over the total amount of gel generated.

5. The method of claim 1, wherein the modified cellulose fiber nonwoven material for ice crystal film is characterized by, The soluble metal anode in step 3 is an alloy anode composed of at least two biocompatible metals; when a DC voltage is applied in step 4, the different metal components in the alloy anode undergo competitive oxidation and dissolution, and at the same time release multiple metal ions as composite crosslinking agents, which react with the biocompatible macromolecules to form a gel network with composite functions.

6. The method of claim 1, wherein the modified cellulose fiber nonwoven material for ice crystal film is characterized by, Before step 3, a pretreatment step is also included: the spunlace nonwoven fabric is placed as a diaphragm in a pretreatment solution containing inorganic salts containing small molecule polyvalent anions, and a DC electric field is applied to this system so that the small molecule polyvalent anions are adsorbed on the fiber surface as precursor ions to optimize the charge environment on the fiber surface; the inorganic salts containing the small molecule polyvalent anions are sodium citrate or sodium tripolyphosphate.

7. The method of claim 1, wherein the modified cellulose fiber nonwoven material for ice crystal film is characterized by, The soluble metal anode in step 3 is a composite functional anode plate, which is spliced ​​together by at least two different pure metal sheets according to a preset pattern corresponding to the facial care area; in step 4, different metal areas of the anode plate release different cross-linked ions in situ, thereby forming a gel of chemical components and functional areas at the corresponding positions on the spunlace nonwoven fabric.

8. The method of claim 1, wherein the modified cellulose fiber nonwoven material for ice crystal film is characterized by, Before step 2, a targeted preloading step is included: using a micro-nozzle or stamp tool, a concentrated liquid containing microcapsules or liposomes encapsulating skin care active ingredients is precisely applied to a specific area of ​​the spunlace nonwoven fabric by dotting or printing; in step 4, the generated gel network anchors and embeds the pre-applied microcapsules or liposomes in situ.

9. The method of claim 1, wherein the modified cellulose fiber nonwoven material for ice crystal film is characterized by, The soluble metal anode in step 3 is a layered composite anode, which is made of at least two different metal foils or sheets laminated together. In step 4, the electrochemical reaction starts from the outermost metal layer. When the outer metal layer is exhausted, the inner metal layer is automatically exposed and takes over the reaction, thereby sequentially depositing a multilayered functional gel on the spunlace nonwoven fabric.

10. The method of claim 1, wherein the modified cellulose fiber nonwoven material for ice crystal film is characterized by, Before step 2, a sacrificial structure embedding step is also included: fibers or slurries made of water-soluble polymer materials are applied or embedded into the spunlace nonwoven fabric according to a preset network pattern; In step 4, a gel network is formed and the sacrificial structure is embedded; during the rinsing process in step 5, the water-soluble polymer material is dissolved and removed, thereby forming in situ interconnected hollow microfluidic channels consistent with the preset network pattern inside the gelled material. The water-soluble polymer material is polyvinyl alcohol; the sacrificial structure is applied to the surface or interior of the spunlace nonwoven fabric using 3D printing or micro-dispensing technology.

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