Sodium alginate modified lyocell fiber needle-punched non-woven fabric mask base cloth and preparation method thereof

Abstract

The invention relates to the technical field of textile materials, and discloses a sodium alginate modified lyocell fiber needle-punched non-woven fabric mask base cloth and a preparation method thereof.The base cloth is formed by interweaving sodium alginate coated modified lyocell fibers through a multi-needle-plate needle punching technology and comprises a lyocell fiber core layer and a sodium alginate hydrogel layer serving as a shell layer, the surface and the tail end of the lyocell fiber are uniformly coated with the hydrogel, the hydrogel and the lyocell fiber form a firm core-shell structure, the hydrogel can expand after absorbing water to fill a strip ring structure and pores formed by needling, a space is provided for water absorption expansion of the hydrogel, the structure can be filled after expansion of the hydrogel, the stiff feeling of needling base cloth is eliminated, the bonding uniformity between the fibers is improved, and the needling quality of the lyocell fiber is improved. Meanwhile, the whole breathable channel of the base cloth is not blocked, and breathability and ductility are both considered; in addition, the liquid absorption capacity of the base cloth can be improved through high water absorption of the hydrogel film, and balance of liquid absorption, liquid retention and softness is achieved in cooperation with the bearing effect of the needling structure.

Description

Technical Field

[0001] This invention relates to the field of textile materials technology, specifically to sodium alginate modified lyocell fiber needle-punched nonwoven fabric mask base and its preparation method. Background Technology

[0002] Sodium alginate is a linear polysaccharide extracted from natural algae such as brown algae. As a natural biomolecular material, it possesses excellent biocompatibility, safety, and hydrophilicity. It is non-toxic, non-irritating, and can be gently tolerated by human skin, and it is completely biodegradable in the natural environment. The mask base fabric, as the carrier of the mask essence, directly determines the user experience, essence carrying efficiency, and skincare auxiliary effects, making it a core component of mask products. Currently, there are many types of mask base fabric materials on the market, mainly including cotton fiber, viscose fiber, lyocell fiber, chemical fiber, and composite fiber. Among them, lyocell fiber is widely used in the preparation of high-end mask base fabrics due to its excellent moisture absorption, breathability, softness, and biodegradability, and the absence of harmful residues.

[0003] However, existing lyocell fiber mask base fabrics still face several technical bottlenecks in practical applications: Firstly, their liquid absorption and retention properties are limited. Although traditional lyocell base fabrics have better moisture absorption than cotton fibers, they struggle to quickly and fully absorb high-concentration, high-viscosity functional essences. Furthermore, the absorbed essence is prone to dripping and loss during use, reducing its utilization rate. Secondly, their softness and skin feel need optimization. Lyocell fibers exhibit fibrillation on their surface, resulting in a high coefficient of friction between fibers. Facial skin is sensitive and delicate, and the sharp ends of lyocell fibers, when used as base fabrics, not only create a noticeably rough feel but also easily cause a stinging sensation when these sharp fiber ends come into contact with the skin. First, it is more likely to cause skin discomfort; second, it lacks antibacterial properties. During the production, storage and use of the mask base fabric, pathogenic bacteria such as Escherichia coli and Staphylococcus aureus can easily grow, posing a risk of skin infection. Existing antibacterial base fabrics mostly rely on the addition of chemical antibacterial agents, which pose irritation and biosafety risks; third, although the hydroentangling process can produce a smooth and delicate base fabric, it has the problems of large water consumption, high production cost and low processing efficiency; although the ordinary needle punching process is low cost and high efficiency, it relies on the needle to puncture and cause the fibers to entangle, which easily forms a stiff strip structure and irregular pores, resulting in a base fabric that is hard to the touch, not easy to stretch, and prone to wrinkling when it fits the facial contours, resulting in poor adaptability.

[0004] Regarding the issues of improving fiber absorbency, maintaining fluidity, softness and skin-friendliness, and inhibiting bacterial growth, a highly moisturizing facial mask based on cellulose fibers and its preparation method have been disclosed. The modified mask base fabric is prepared by treatment with isopropanol, sodium hydroxide, tetramethylammonium hydroxide, propylene oxide, and glucose oxidase. However, the additives in this method are all chemical reagents, and strong alkalis and propylene oxide are prone to leave residues in the base fabric, which may not only irritate the skin but also damage the skin barrier, and also poses poor environmental safety. This paper discloses a water-absorbing and gelling spunlace fabric containing seaweed fibers and its preparation method, as well as a method for preparing a composite seaweed fiber mask base fabric based on grafted modified propylene glycol alginate. The former is composed of seaweed fibers and other hydrophilic fibers, which gel upon absorbing water. However, in this technical solution, the fibers are randomly mixed and entangled, resulting in uneven dispersion of the seaweed fibers. Furthermore, the high pressure of the spunlace process leads to local compaction of the fabric surface and uneven porosity. The latter improves the moisture absorption of the base fabric by grafting a modifier of octyl mercaptan and diallylamine onto the macromolecules of propylene glycol alginate. However, it suffers from drawbacks such as cumbersome process, high temperature and energy consumption, and easy damage to the fiber structure, affecting the skin feel. A method for preparing lyocell fibers containing Chlorella components is also disclosed, which improves the antibacterial properties of the fibers by adding natural Chlorella extract and flame-retardant antibacterial compounds. However, existing modification technologies have defects. For example, the chemical grafting modification process is complex, requiring multiple steps such as high-temperature ester exchange and chelation adsorption, which easily damages the original structure of the lyocell fibers, leading to a decrease in softness and poor environmental performance. Adding antibacterial ingredients directly, such as extracts and fibers, is merely a physical mixture with low binding strength, making it easy to fall off during use and resulting in insufficient antibacterial effect. Summary of the Invention

[0005] The purpose of this invention is to provide sodium alginate modified lyocell fiber needle-punched nonwoven fabric for facial masks and its preparation method, so as to solve the technical problems of existing facial mask base fabrics such as poor skin adhesion, low liquid carrying capacity, reliance on chemical antibacterial agents, and difficulty in stretching.

[0006] The technical solution of the present invention is as follows:

[0007] The mask base fabric is a sodium alginate-modified lyocell fiber needle-punched nonwoven fabric. The mask base fabric has a fiber entanglement network porous structure. The fiber entanglement network porous structure is formed by multiple sodium alginate-modified lyocell fibers entangled with each other through a needle-punching process. The fiber entanglement network porous structure includes lyocell fibers as the core layer and a sodium alginate hydrogel layer covering the surface of the core layer as the shell layer.

[0008] Further optimization involves the sodium alginate hydrogel layer being a dense hydrogel film formed by the cross-linking of sodium alginate and calcium chloride, and the sodium alginate hydrogel layer also coating the ends of the lyocell fibers.

[0009] Further optimization is achieved by using a sodium alginate hydrogel layer with a thickness of 50-200 nm and a mask base fabric with a basis weight of 60-90 g / m².2 .

[0010] The preparation method of sodium alginate modified lyocell fiber needle-punched nonwoven fabric mask base fabric includes the following steps:

[0011] Step 1: Immerse Lyocell fibers in a coating solution of sodium alginate and calcium ion crosslinking agent, so that sodium alginate and calcium ion crosslinking agent form a sodium alginate hydrogel layer and coat the surface of Lyocell fibers to obtain sodium alginate modified Lyocell fibers.

[0012] Step 2: Card the sodium alginate modified lyocell fibers into a web, and then perform a needle punching process.

[0013] Reinforcement is used to form the base fabric blank;

[0014] Step 3: Dry the base fabric blank to obtain sodium alginate modified lyocell fiber mask base fabric.

[0015] Further optimization involves the following: the mass concentration of sodium alginate in the coating solution is 0.1-10%, the mass concentration of the calcium ion crosslinking agent is 0.1-10%, and the pH value of the coating solution is 6.5-7.5.

[0016] Further optimization involves using calcium chloride as the calcium ion crosslinking agent, with an impregnation bath ratio of (1:10) to (1:50). After impregnation, the process further includes rinsing the fibers with deionized water to remove free sodium alginate and uncrosslinked calcium ions from the surface.

[0017] To further optimize the process, before step 1, a pretreatment step for the lyocell fiber is included: the lyocell fiber is ultrasonically cleaned in deionized water and then dried to a constant weight.

[0018] Further optimization involves using a multi-needle plate needle punching process in step 2, where multiple sets of needle plates alternately puncture the fibers to intertwine and entangle them, forming a base fabric blank with a loop structure and pores.

[0019] Further optimization involves ensuring that the moisture content of the mask base fabric is 1-10% after drying in step 3.

[0020] The beneficial effects of this application are:

[0021] 1. By utilizing the high water absorption of the sodium alginate hydrogel layer, the essence is quickly absorbed and stored in the gel network. At the same time, the microporous structure of the lyocell fiber absorbs the liquid simultaneously. This dual effect greatly increases the liquid absorption rate of the base fabric, which can absorb up to 15-20 times its own weight. This effectively solves the problems of low water absorption and short moisturizing time of existing base fabrics, achieving long-lasting moisturizing. In addition, the hydrogel filling the pores can reduce the dripping of essence and improve utilization.

[0022] 2. After absorbing water, the hydrogel expands in the upward, downward and left and right directions to fill the needle-punched pores and strip structure, improve the stiffness of the needle-punched base fabric, enhance its extensibility, make it easy to stretch and closely fit the facial contours without wrinkles, and adapt to various face shapes.

[0023] 3. By completely encapsulating the surface and ends of Lyocell with sodium alginate hydrogel, the part in contact with facial skin becomes a soft and smooth hydrogel, reducing the coefficient of friction between fibers, avoiding the problems of fibrillation and sharp ends of Lyocell fibers, eliminating irritation from fibrillation of Lyocell fibers and fiber residue, improving skin-friendliness, and eliminating the phenomenon of hair loss and fiber residue after use, simplifying the cleansing process after use.

[0024] 4. Both sodium alginate and lyocell fiber are natural biodegradable materials with excellent biocompatibility. Sodium alginate has natural antibacterial properties, releasing antibacterial active ingredients. The three-dimensional gel network formed by cross-linking with calcium chloride can, under neutral conditions, adsorb and encapsulate bacteria and slowly release free Ca²⁺ to interfere with bacterial enzyme activity. It is non-toxic, non-chemically irritating, and suitable for sensitive skin. At the same time, all materials used are biodegradable, which is in line with the trend of green and environmentally friendly development. It also has certain anti-mildew properties and improves the storage stability of the product.

[0025] 5. The multi-needle plate needle punching process significantly reduces water consumption, lowers costs, and improves efficiency compared to the hydroentangling process. Moreover, the preparation process does not require complex equipment, the process is mature and controllable, and it is suitable for large-scale mass production. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of the mask base fabric with a fiber entangled mesh porous structure in Example 1;

[0027] Figure 2 This is a schematic diagram of the structure of sodium alginate modified lyocell fiber in Example 1;

[0028] Figure reference numerals: 1-Lyocell fiber, 2-Sodium alginate hydrogel layer. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only for explaining the invention and are not intended to limit the invention; that is, the described embodiments are merely some embodiments of the invention, and not all embodiments. The components of the embodiments of the invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0030] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0031] It should be noted that relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0032] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0033] Example 1

[0034] This embodiment provides a sodium alginate-modified lyocell fiber needle-punched nonwoven fabric mask base fabric. This mask base fabric has a fiber entanglement network porous structure, formed by multiple sodium alginate-modified lyocell fibers intertwined through a needle-punching process. The fiber entanglement network porous structure includes a lyocell fiber 1 as the core layer and a sodium alginate hydrogel layer 2 covering the surface of the core layer and serving as the shell layer. The sodium alginate hydrogel layer 2 is a dense hydrogel film formed by the cross-linking of sodium alginate and calcium chloride, and it covers the ends of the lyocell fiber 1. The thickness of the sodium alginate hydrogel layer is 80 nm, and the basis weight of the mask base fabric is 70 g / m². It is prepared through the following steps:

[0035] Lyocell fiber 1 was ultrasonically cleaned in deionized water for 20 minutes at an ultrasonic power of 300W, and then dried in an 80℃ oven until constant weight for later use.

[0036] Sodium alginate was dissolved in deionized water and stirred to prepare a 2% sodium alginate solution. Then, 1% calcium chloride was added as a calcium ion crosslinking agent. The solution was stirred continuously at 80°C for 30 minutes until it was mixed evenly. The pH of the coating solution was adjusted to 6.8 with citric acid solution to obtain a stable coating solution.

[0037] The pretreated Lyocell fiber was immersed in the above coating solution, and the bath ratio of Lyocell fiber to coating solution was controlled at 1:20. The mixture was stirred at a constant temperature of 25°C for 60 minutes to allow sodium alginate to fully crosslink with calcium chloride to form sodium alginate hydrogel layer 2, which was uniformly coated on the surface and ends of Lyocell fiber 1. Then Lyocell fiber 1 was taken out and rinsed with deionized water 3 times for 10 minutes each time to remove free sodium alginate and calcium ions that did not participate in crosslinking. The fiber was then dried to obtain sodium alginate modified Lyocell fiber.

[0038] Sodium alginate-modified lyocell fibers were fed into a carding machine and carded into a web to obtain a uniform fiber web. This web was then reinforced using a multi-needle plate needle punching process, employing three sets of needle plates that alternately punched the fibers at a needle density of 250 needles / cm². 2 The needle-punching depth is 8mm, which causes the fibers to intertwine and entangle, forming a base fabric blank with a strip loop structure and pores;

[0039] The base fabric blank was placed in an 85℃ oven and dried for 60 minutes. The moisture content of the dried film base fabric was controlled to be 6%, thus obtaining sodium alginate modified lyocell fiber needle-punched nonwoven fabric mask base fabric.

[0040] The mask base fabric prepared in Example 1 is as follows: Figure 1 As shown, sodium alginate and calcium chloride crosslink to form a three-dimensional network hydrogel that coats the surface and ends of lyocell fibers. Simultaneously, the hydrogel and the needle-punched structure work synergistically. The carboxyl groups on the sodium alginate molecular chain form hydrogen bonds with the hydroxyl groups on the lyocell fiber surface, and combined with calcium chloride crosslinking, form a dense and robust hydrogel film that completely coats the fiber ends, preventing sharp irritation. The strip-like structure and pores formed by the multi-needle plate needle-punching process provide space for the hydrogel to absorb water and expand. After expansion, the hydrogel fills the aforementioned structure, eliminating the stiffness of the needle-punched base fabric, improving the uniformity of fiber bonding, and without blocking the overall air permeability channels of the base fabric, thus balancing breathability and extensibility. Furthermore, the high water absorption of the hydrogel film itself enhances the liquid absorption capacity of the base fabric, and combined with the load-bearing function of the needle-punched structure, achieves a balance between liquid absorption and retention and softness.

[0041] Example 2

[0042] This embodiment provides a sodium alginate-modified lyocell fiber needle-punched nonwoven fabric mask base fabric. This mask base fabric has a fiber entanglement network porous structure, formed by multiple sodium alginate-modified lyocell fibers intertwined through a needle-punching process. The fiber entanglement network porous structure includes a lyocell fiber 1 as the core layer and a sodium alginate hydrogel layer 2 covering the surface of the core layer and serving as the shell layer. The sodium alginate hydrogel layer 2 is a dense hydrogel film formed by the cross-linking of sodium alginate and calcium chloride, and it covers the ends of the lyocell fiber 1. The thickness of the sodium alginate hydrogel layer is 150 nm, and the basis weight of the mask base fabric is 80 g / m². It is prepared through the following steps:

[0043] (1) Place the Lyocell short fibers in deionized water and ultrasonically clean for 30 minutes with an ultrasonic power of 350W. Then place them in an 85℃ oven to dry to constant weight for later use.

[0044] (2) Dissolve sodium alginate in deionized water, stir to dissolve and prepare a sodium alginate solution with a mass concentration of 6%, then add calcium chloride with a mass concentration of 5% as a calcium ion crosslinking agent, stir continuously at 80℃ for 40 min until the mixture is uniform, adjust the pH of the coating solution to 7.2 with citric acid solution to obtain a stable coating solution;

[0045] (3) The pretreated Lyocell fiber was immersed in the above coating solution, and the bath ratio of Lyocell fiber to coating solution was controlled to be 1:40. The mixture was stirred at a constant temperature of 25°C for 60 min to allow sodium alginate to fully crosslink with calcium chloride to form sodium alginate hydrogel, which was uniformly coated on the surface and end of Lyocell fiber. Then Lyocell fiber 1 was taken out and rinsed with deionized water 3 times for 10 min each time to remove free sodium alginate and calcium ions that did not participate in crosslinking. The fiber was then dried to obtain sodium alginate modified Lyocell fiber.

[0046] (4) The sodium alginate modified lyocell fiber is fed into a carding machine and carded into a web to obtain a uniform fiber web. Then, it is reinforced by a multi-needle plate needle punching process. Three sets of needle plates are used to alternately punch the web, and the needle punching density is 250 needles / cm. 2 The needle-punching depth is 8mm, which causes the fibers to intertwine and entangle, forming a base fabric blank with a strip loop structure and pores;

[0047] (5) Place the base fabric blank in a 90℃ oven and dry for 60 minutes. Control the moisture content of the dried film base fabric to 4% to obtain sodium alginate modified Lyocell fiber needle-punched nonwoven fabric mask base fabric.

[0048] Example 3

[0049] This embodiment provides a sodium alginate-modified lyocell fiber needle-punched nonwoven fabric mask base fabric. This mask base fabric has a fiber entanglement network porous structure, formed by multiple sodium alginate-modified lyocell fibers intertwined through a needle-punching process. The fiber entanglement network porous structure includes a lyocell fiber 1 as the core layer and a sodium alginate hydrogel layer 2 covering the surface of the core layer and serving as the shell layer. The sodium alginate hydrogel layer 2 is a dense hydrogel film formed by the crosslinking of sodium alginate and calcium chloride, and it covers the ends of the lyocell fiber 1. The thickness of the sodium alginate hydrogel layer 2 is 200 nm, and the basis weight of the mask base fabric is 90 g / m². It is prepared through the following steps:

[0050] (1) Place the Lyocell short fibers in deionized water and ultrasonically clean for 25 minutes with an ultrasonic power of 320W. Then place them in an 82℃ oven to dry to constant weight for later use.

[0051] (2) Dissolve sodium alginate in deionized water, stir to dissolve and prepare a sodium alginate solution with a mass concentration of 3%, then add calcium chloride with a mass concentration of 2% as a calcium ion crosslinking agent, stir continuously at 80°C for 30 minutes until the mixture is uniform, adjust the pH of the coating solution to 7.5 with citric acid solution to obtain a stable coating solution;

[0052] (3) The pretreated Lyocell fiber was immersed in the above coating solution, and the bath ratio of Lyocell fiber to coating solution was controlled to be 1:50. The mixture was stirred at a constant temperature of 25°C for 60 min to allow sodium alginate to fully crosslink with calcium chloride to form sodium alginate hydrogel, which was uniformly coated on the surface and end of Lyocell fiber. Then Lyocell fiber 1 was taken out and rinsed with deionized water 3 times for 10 min each time to remove free sodium alginate and calcium ions that did not participate in crosslinking. The fiber was then dried to obtain sodium alginate modified Lyocell fiber.

[0053] (4) The sodium alginate modified lyocell fiber is fed into a carding machine and carded into a web to obtain a uniform fiber web. Then, it is reinforced by a multi-needle plate needle punching process. Three sets of needle plates are used to alternately punch the web, and the needle punching density is 250 needles / cm. 2 The needle-punching depth is 8mm, which causes the fibers to intertwine and entangle, forming a base fabric blank with a strip loop structure and pores;

[0054] (5) Place the base fabric blank in a 95℃ oven and dry for 60 minutes. Control the moisture content of the dried film base fabric to 10% to obtain sodium alginate modified Lyocell fiber needle-punched nonwoven fabric mask base fabric.

[0055] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. The scope of patent protection of the present invention shall be determined by the claims. Similarly, any equivalent structural changes made based on the description and drawings of the present invention shall also be included within the scope of protection of the present invention.

Claims

1. A sodium alginate-modified lyocell fiber needle-punched nonwoven fabric mask base fabric, characterized in that, The mask base fabric is a fiber entangled mesh porous structure. The fiber entangled mesh porous structure is formed by multiple sodium alginate modified lyocell fibers intertwined through a needle punching process. The fiber entangled mesh porous structure includes lyocell fibers (1) as the core layer and sodium alginate hydrogel layer (2) covering the surface of the core layer and serving as the shell layer.

2. The sodium alginate-modified lyocell fiber needle-punched nonwoven fabric mask base fabric according to claim 1, characterized in that, The sodium alginate hydrogel layer (2) is a dense hydrogel film formed by cross-linking sodium alginate and calcium chloride, and the sodium alginate hydrogel layer (2) also covers the ends of the lyocell fiber (1).

3. The mask base fabric of sodium alginate modified lyocell fiber needle-punched nonwoven fabric according to claim 1, characterized in that, The sodium alginate hydrogel layer (2) has a thickness of 50-200 nm, and the base fabric of the mask has a basis weight of 60-90 g / m². 2 .

4. A method for preparing sodium alginate-modified lyocell fiber needle-punched nonwoven fabric mask base fabric, characterized in that, Includes the following steps: Step 1: Immerse Lyocell fiber (1) in a coating solution of sodium alginate and calcium ion crosslinking agent, so that sodium alginate and calcium ion crosslinking agent form a sodium alginate hydrogel layer (2) and coat the surface of Lyocell fiber (1) to obtain sodium alginate modified Lyocell fiber. Step 2: The sodium alginate modified lyocell fiber is combed into a web and then reinforced by needle punching to form the base fabric blank; Step 3: Dry the base fabric blank to obtain sodium alginate modified lyocell fiber mask base fabric.

5. The preparation method according to claim 4, characterized in that, The coating solution contains sodium alginate at a mass concentration of 0.1-10%, calcium ion crosslinking agent at a mass concentration of 0.1-10%, and the coating solution has a pH value of 6.5-7.

5.

6. The preparation method according to claim 4, characterized in that, The calcium ion crosslinking agent is calcium chloride, and the impregnation bath ratio is (1:10)-(1:50); after impregnation, the fiber is rinsed with deionized water to remove free sodium alginate and calcium ions that have not participated in crosslinking.

7. The preparation method according to claim 4, characterized in that, Before step 1, a pretreatment step for the lyocell fiber is included: the lyocell fiber (1) is ultrasonically cleaned in deionized water and then dried to constant weight.

8. The preparation method according to claim 4, characterized in that, In step 2, the needle punching process is a multi-needle plate needle punching process, in which multiple sets of needle plates alternately puncture to make the fibers intertwine and entangle, forming a base fabric blank with a strip loop structure and pores.

9. The preparation method according to claim 4, characterized in that, After the base fabric blank is dried in step 3, the moisture content of the mask base fabric is 1-10%.

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