Radiation heat protection forest fire extinguishing suit fabric

Abstract

The radiation heat protection forest fire extinguishing suit fabric comprises a surface layer, an inner layer and binding yarns used for connecting the two layers. The surface layer is of a tiny concave-convex structure formed by interweaving various fibers and yarns with different yarn counts, and the yarns of the surface layer comprise silver-plated nylon fibers and at least two of polyimide fibers, meta-aramid fibers and para-aramid fibers. The inner layer is formed by weaving inner layer yarns, and at least one of the inner layer yarns comprises para-aramid and flame-retardant viscose. According to the fabric, the radiation heat reflection efficiency is remarkably improved through the cooperation of chemical reflection of the silver-plated nylon fiber on the surface layer and physical diffuse reflection of the macroscopic concave-convex structure. And the inner layer realizes the balance of skin-friendly moisture absorption and high strength. On the premise of not increasing load, the radiation heat protection value and the heat protection performance of the fabric are greatly improved, the fabric has excellent antibacterial performance, antistatic performance and heat and moisture comfort, and all-around safety guarantee is provided for firemen.

Description

Technical Field

[0001] This application belongs to the field of special functional textile technology, specifically relating to a radiant heat protective forest fire fighting suit fabric and a method for preparing the radiant heat protective forest fire fighting suit fabric. Background Technology

[0002] Forest firefighting operations operate in extremely complex environments. Firefighters not only face direct threats from flames but also prolonged exposure to high-intensity, high-temperature radiant heat. Radiant heat, as one of the main forms of energy transfer in a fire, is a key factor causing heat burns and even heat stress in firefighters. Therefore, developing firefighting suit fabrics that can effectively block radiant heat while meeting the requirements for mountain mobility is a core issue for improving firefighter safety and combat effectiveness. Summary of the Invention

[0003] The first aspect of this application provides a radiant heat protective forest fire fighting suit fabric, the fabric including an outer layer, an inner layer, and a bonding yarn for connecting the outer layer and the inner layer. The surface layer is woven from various surface yarns with different fiber compositions and yarn counts to form a micro-uneven structure. The surface yarns include silver-plated nylon fibers; the surface yarns also include at least two of the following: polyimide fibers, meta-aramid fibers, and para-aramid fibers. The inner layer is woven from inner layer yarns, at least one of which contains para-aramid and flame-retardant viscose.

[0004] The second aspect of this application provides a method for preparing a radiant heat protective forest firefighting suit fabric as described in the first aspect of this application, wherein the outer layer yarn includes an outer layer warp yarn and an outer layer weft yarn; the inner layer yarn includes an inner layer warp yarn and an inner layer weft yarn, and the method includes the following steps: Yarn preparation steps include: preparing the outer layer yarn, inner layer yarn, and splicing yarn; The pre-weaving preparation steps include: calculating the total number of warp threads for the surface warp and the inner warp according to the arrangement ratio based on the fabric weight and yarn count; warping the surface warp and the inner warp separately to form surface warp beams and inner warp beams; integrating the surface warp beams and the inner warp beams into surface warp beams and inner warp beams using a sizing machine; sizing the surface warp; and, according to the designed fabric structure diagram and the warp and weft density configuration and cycle of the surface and inner layers, threading the surface warp and the inner warp into different heddle frames using a forward threading method, and then threading the threaded yarns onto the reed to complete the pre-weaving preparation. The weaving process includes: installing the warp beam prepared in the pre-weaving preparation step onto the loom, using a rapier double warp beam loom, setting the back beam to the middle back beam position, and adjusting the height of the lower back beam to 1000-1080 mm; installing the surface warp beam as the upper warp beam and the inner warp beam as the lower warp beam; setting the tension of the upper warp beam to 600-750 MV and the tension of the lower warp beam to 100-150 MV, and weaving in a cycle according to the designed weft yarn arrangement; The finishing steps include: using desizing enzyme to desize the greige fabric obtained from the weaving process to remove the sizing material applied to the warp yarns during weaving; washing away stains and desizing enzyme from the fabric surface; performing a durable waterproofing treatment on the fabric; and stretching the fabric to a specified width and stabilizing its dimensions under appropriate temperature and tension to obtain the finished fabric. Attached Figure Description

[0005] Figure 1 This is a schematic diagram of the yarn arrangement on the surface layer of a double-layer fabric according to an embodiment of this application.

[0006] Figure 2 This is a schematic diagram of the arrangement and weave structure of the inner layer yarns according to an embodiment of this application.

[0007] Figure 3 This is a schematic diagram of the structure of the inner and outer layer connection according to an embodiment of this application.

[0008] Figure 4 This is a schematic diagram of the joint spacing and joint loop according to an embodiment of this application. Detailed Implementation

[0009] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0010] Through extensive research, the inventors of this application have discovered that the commercially available or literature-reported forest firefighting clothing fabrics currently suffer from the following technical bottlenecks in addressing the threat of radiant heat, resulting in their overall performance failing to meet the needs of frontline combat.

[0011] First, the radiant heat protection mechanisms are simplistic and inefficient. Current technologies for improving heat protection primarily focus on increasing fabric thickness or applying dense coatings such as aluminum foil or flame-retardant silicone. The former directly leads to excessive fabric weight, exacerbating the physical exertion of firefighters during mountainous terrain; the latter, while reflecting some radiant heat, completely seals off the fabric's breathability and moisture-wicking channels, easily causing heat and sweat buildup during prolonged work, triggering severe heat and moisture stress, which also jeopardizes safety. In other words, existing solutions fail to establish an effective balance between the conflicting needs of reflecting radiant heat and expelling body heat and moisture.

[0012] Secondly, the synergy of material functions is poor, failing to construct a systematic protective layer. While many fabrics utilize high-performance flame-retardant fibers such as aramid and polyimide, their application often remains at the level of simple material stacking or homogeneous blending. For example, the surface fabric may use only a single type or proportion of aramid fibers, focusing primarily on flame retardancy and mechanical strength, while offering limited reflectivity against radiant heat. There is a lack of a design approach that can finely and progressively combine reflectivity, high-temperature resistance, and the inherent flame-retardant properties of the fibers. Therefore, it is impossible to form a highly efficient composite protective layer on the fabric surface that actively manages radiant heat while also ensuring durability.

[0013] Third, the comfort layer structure is rudimentary and struggles to achieve long-lasting dryness. The design of the side of the fabric closest to the skin is often neglected, or only hydrophobic synthetic fibers such as pure aramid are used to ensure strength. This prevents sweat from being quickly absorbed and wicked away from the skin, and moisture accumulates within the garment's microclimate, causing not only stuffiness and discomfort but also increasing the risk of burns due to moisture evaporation when exposed to high temperatures. Therefore, there is an urgent need for an inner layer structure that can achieve rapid absorption, diffusion, and evaporation of sweat while maintaining necessary strength, fundamentally improving wearing comfort and thermal safety.

[0014] In summary, existing forest firefighting clothing fabrics present a trade-off between protection and comfort in terms of radiant heat protection. This stems from systemic deficiencies in material selection, structural design, and functional integration. There is an urgent need for an innovative fabric design that can substantially improve radiant heat protection without significantly increasing weight or sacrificing breathability, while ensuring comfort during long-term operations.

[0015] Therefore, this application provides a radiant heat protective forest firefighting suit fabric 10, including an outer layer 110, an inner layer 120, and a bonding yarn for connecting the outer and inner layers. The outer layer is woven from multiple outer layer yarns of different fiber compositions and yarn counts to form a textured structure, and the outer layer yarns include silver-plated nylon fibers. The outer layer yarns also include at least two of polyimide fibers, meta-aramid fibers, and para-aramid fibers. The inner layer is woven from the inner layer yarns, and at least one inner layer yarn contains para-aramid and flame-retardant viscose.

[0016] First, in the surface design, silver-plated nylon fiber was introduced as the core functional unit for reflecting radiation heat.

[0017] Radiant heat is essentially electromagnetic waves, primarily located in the infrared band. Silver-plated fibers can efficiently reflect radiant heat because: First, silver has the highest electrical and thermal conductivity of all metals, and its outermost free electrons are extremely sensitive to electromagnetic waves. When infrared radiation acts on the silver layer, the free electrons oscillate at high speed and generate a reverse electromagnetic field, thus reflecting most of the energy back; its infrared reflectivity can reach over 95%. Second, the silver layer has extremely low emissivity, meaning it can not only reflect external heat but also effectively suppress secondary radiation into the interior after absorbing heat, forming a two-way thermal barrier. Third, in the fabric of this embodiment, the silver-plated nylon fibers are blended into the surface yarn. These discretely distributed silver fibers form countless microscopic reflective surfaces on the fabric surface, causing the incident thermal radiation to be continuously diffusely reflected, thus significantly attenuating the energy.

[0018] The inventors of this application have discovered through extensive research that silver plating on nylon fiber substrates yields better results than silver plating on other surface yarns. This is because: First, the amide bonds in nylon molecules have a strong affinity for silver ions, achieving a strong molecular-level bond during chemical silver plating. This ensures the silver layer is not easily peeled off after vigorous movement and frequent washing. In contrast, the surfaces of fibers such as aramid are too smooth and stable, resulting in poor silver adhesion. Second, nylon fibers possess excellent toughness, abrasion resistance, and wrinkle resistance. Their high elasticity ensures the continuity and integrity of the ultra-thin silver layer on the surface when the fabric is subjected to stretching, bending, and other deformations, thus maintaining stable reflective and conductive properties. If the substrate is easily broken or deformed, the silver layer will crack and fail. Third, nylon fibers have a certain degree of hygroscopicity, which helps to accommodate more silver ions. This allows the silver-plated nylon to not only perform high reflectivity and conductivity but also achieve long-lasting antibacterial effects through the release of silver ions, which is particularly important in firefighting environments where sweating is extremely high. Fourth, although nylon itself generally has low heat resistance, in the surface formulation of this application embodiment, the proportion of silver-plated nylon is controlled at a low level. It is mainly encapsulated as a functional unit within a large amount of high-temperature resistant fibers such as polyimide and aramid. The extremely high reflectivity of the silver layer can reflect a large amount of radiant heat in the early stages of a fire, thereby protecting itself and the surrounding fiber substrate. This demonstrates a clever balance between functional synergy and sacrificial protection.

[0019] Secondly, in the surface design, silver-plated nylon fibers are composited with at least two of the following: polyimide fibers, meta-aramid fibers, and para-aramid fibers. By interweaving different fiber components with various yarn counts, a macroscopic concave-convex structure is ultimately formed. This design strategy directly addresses the problems of limited radiative heat protection mechanisms and poor material synergy in existing technologies. It aims to construct a composite functional surface layer that combines high reflectivity, high temperature resistance, flame retardancy, and structural durability, thereby enhancing active defense against radiative heat from the source.

[0020] The textured surface significantly enhances radiative heat protection performance, primarily through several key mechanisms. First, it utilizes diffuse reflection. While smooth, flat surfaces allow radiation waves to penetrate or be absorbed directly, surfaces with textured microstructures alter the angle of incidence, scattering heat radiation in multiple directions and reducing the amount of heat entering the fabric per unit area. Second, it increases the effective reflective surface area. The interwoven textured structure effectively increases the physical surface area of ​​the fabric. Because the surface yarns contain highly reflective silver-plated nylon fibers, these metallized fibers, distributed across the undulating surface, more effectively intercept and reflect radiative heat from different angles. Third, it creates a micro-air buffer layer. The uneven surface creates tiny air gaps between the external heat source and the fabric, and air, being an excellent insulator, helps slow the rate at which heat is conducted into the deeper layers of the fabric.

[0021] In this embodiment, the uneven structure is designed through precise material ratios and differences in physical specifications. First, the difference in yarn thickness creates a physical thickness difference; thicker yarns will protrude more than thinner yarns during weaving. When these yarns of varying thicknesses are interwoven in a specific ratio, the fabric surface naturally exhibits unevenness. Second, the difference in resilience and thermal shrinkage rates of different fibers creates a chemical displacement difference. Fibers such as polyimide, aramid, and silver-plated nylon have different moduli and thermal shrinkage characteristics, resulting in slight tension changes during finishing or heating. Yarns with lower shrinkage rates remain crisp or even protrude, while yarns with higher shrinkage rates shrink, further enhancing the uneven surface morphology. Third, through specific fabric weave cycles, crisscrossing raised ribs can be constructed on the fabric surface, thereby solidifying the uneven geometric features of the fabric surface.

[0022] Furthermore, a crucial synergistic effect exists between the textured surface and the silver-plated nylon fibers. The textured surface, as the physical basis, alters the incident angle of heat radiation, inducing highly efficient diffuse reflection. Meanwhile, the silver-plated nylon fibers, as chemical functional elements, form countless microscopic mirrors on the textured surface. If only the textured surface exists, the reflectivity of radiative heat is limited; if only silver-plated nylon exists, the reflection angle is singular and may fail due to adhesion issues. Only by organically combining the two can the radiative heat protection value of the fabric be substantially improved without increasing the fabric thickness.

[0023] Third, in the inner layer design, at least one inner layer yarn must contain para-aramid and flame-retardant viscose. This design provides the necessary strength support for the inner layer through para-aramid, while introducing moisture-wicking function through flame-retardant viscose, thus laying the material foundation for building a strong yet skin-friendly and moisture-wicking comfortable layer. This aims to improve the garment's ability to manage its microclimate and enhance wearing comfort during long working hours.

[0024] Through targeted design of materials and functions in the outer and inner layers, the embodiments of this application achieve multiple beneficial effects. Regarding radiative heat protection, the silver-plated nylon fiber itself has high reflectivity, while the uneven structure formed by the interweaving of various yarns with different fiber compositions and counts increases the diffuse reflection of light and heat radiation, collectively reducing direct heat absorption. In terms of basic heat protection and mechanical strength, polyimide and aramid fibers are high-temperature resistant and flame-retardant fibers, providing the fabric with basic heat resistance and flame retardant properties, while para-aramid provides high-strength support for the inner layer. Regarding wearing comfort, flame-retardant viscose fiber has good moisture absorption, effectively improving the skin-friendly feel of the inner layer. Ultimately, through this innovative material combination and structural design, this invention synergistically resolves the inherent contradiction between high radiative heat protection and wearing comfort within a single fabric system, achieving a comprehensive improvement in both protective and comfort performance.

[0025] In some embodiments, the surface layer is woven from yarns A, B, and C; yarn A comprises 15%-25% polyimide fiber, 60%-70% meta-aramid fiber, 0%-15% flame-retardant viscose, and 2%-6% silver-plated nylon fiber, with the sum of all components being 100%; yarn B comprises 10%-22% para-aramid fiber, 75%-85% meta-aramid fiber, and 3%-8% silver-plated nylon fiber, with the sum of all components being 100%; yarn C comprises 30%-42% para-aramid fiber, 52%-65% meta-aramid fiber, and 3%-6% silver-plated nylon fiber, with the sum of all components being 100%. Unless otherwise specified, the proportions mentioned in this application are percentages by weight.

[0026] In this embodiment, the surface layer is woven from three specific yarns with complementary functions: yarn A, yarn B, and yarn C. Each yarn uses a carefully designed fiber quality ratio to ensure that the fabric surface layer achieves optimal synergistic effects in terms of mechanical properties, heat resistance, and radiative heat reflection.

[0027] The A-yarn forms the basic heat-resistant and reflective matrix of the surface layer. It consists of the following fiber weight percentages: 15% to 25% polyimide fiber, 60% to 70% meta-aramid fiber, 0% to 15% flame-retardant viscose fiber, and 2% to 6% silver-plated nylon fiber, with the sum of all components being 100%. This ratio is determined by multiple considerations: a higher proportion of meta-aramid (such as aramid 1313) provides excellent inherent flame retardancy, heat resistance, and thermal stability, acting as the first line of defense against flames and high temperatures. The introduction of polyimide fiber further enhances the overall high-temperature resistance limit and heat shrinkage resistance, complementing the meta-aramid. A small but essential amount of silver-plated nylon fiber (2%-6%) acts as a key functional element, uniformly dispersed within the matrix, responsible for efficiently reflecting radiant heat. The addition of flame-retardant viscose fiber (0%-15%) can adjust the spinnability, hand feel and cost of the yarn. Its content can be flexibly adjusted between 0 and 15% to meet different performance requirements.

[0028] Yarn B serves as a reinforcing and functional supplementary unit for the surface layer. It comprises the following fiber weight percentages: 10% to 22% para-aramid fiber, 75% to 85% meta-aramid fiber, and 3% to 8% silver-plated nylon fiber, with the sum of all components being 100%. This formulation is designed to: maintain excellent flame retardancy and heat resistance with a high proportion of meta-aramid; and introduce a certain proportion of para-aramid (such as aramid 1414) to significantly enhance the tensile, tear, and puncture resistance of the yarn and the final fabric, thereby improving the fabric's mechanical durability, utilizing its extremely high strength and modulus. Simultaneously, compared to yarn A, yarn B contains a slightly higher content of silver-plated nylon fiber (3%-8%), aiming to further enhance localized radiative heat reflection efficiency.

[0029] C-yarn primarily serves as the skeleton and densification unit of the surface structure. It is composed of the following fiber weight percentages: 30% to 42% para-aramid fiber, 52% to 65% meta-aramid fiber, and 3% to 6% silver-plated nylon fiber, with the sum of all components being 100%. In this composition, the significantly increased proportion of para-aramid (30%-42%) gives C-yarn extremely high rigidity and strength, making it ideal for use as warp yarn, providing stable structural support and dimensional stability for the entire surface fabric. Meta-aramid ensures its heat resistance, while a certain amount of silver-plated nylon fiber ensures that this skeleton unit also possesses basic reflective properties, preventing it from becoming a weak point in heat absorption.

[0030] The three yarns, A, B, and C, were designed based on a comprehensive consideration of the flame-retardant main framework, reflective functional points, and strong reinforcing ribs. By controlling the ratio difference between heat-resistant meta-aramid and strong para-aramid, the fabric can maximize local strength without increasing the overall thickness.

[0031] Moreover, all the yarns on the surface contain silver-plated nylon, which ensures that the surface maintains a relatively uniform reflective coating density regardless of the direction in which the fabric is stretched or wrinkled, and will not form heat radiation transmission gaps due to the low proportion of a certain yarn.

[0032] In some embodiments, the inner layer is woven from yarns B, D, and E; yarn D is a wrapping yarn composed of 100% para-aramid staple fiber yarn and 100% flame-retardant viscose staple fiber yarn, with the flame-retardant viscose staple fiber yarn located on the outer layer of yarn D; yarn E is para-aramid filament.

[0033] In this embodiment, the inner layer is woven from three types of yarns: B yarn, D yarn, and E yarn. This combination aims to achieve high strength, high comfort, and extended functionality simultaneously within the inner layer.

[0034] D-yarn is the core design element for achieving comfort in the inner layer. It is a composite yarn made using a special wrapping process. Specifically, D-yarn consists of a core yarn of 100% pure para-aramid staple fiber and an outer yarn of 100% pure flame-retardant viscose staple fiber, combined through a high-twist wrapping method. In this structure, the flame-retardant viscose staple fiber is deliberately placed on the outer layer of D-yarn. This design has crucial functional significance. When the fabric is made into clothing and worn, the flame-retardant viscose fiber on the outer layer can directly and fully contact the skin. Flame-retardant viscose fiber has good hydrophilicity and excellent moisture absorption and quick-drying properties, which can quickly absorb the sweat produced by the human body and conduct the moisture to the outer layer of the fabric for evaporation through the wicking effect, thereby keeping the skin contact surface dry and comfortable at all times, effectively alleviating the heat and humidity stress of firefighters under high-intensity operations. Meanwhile, the para-aramid staple fiber yarn, which serves as the core yarn, provides strong internal support for the D yarn, ensuring that the yarn can maintain good shape and mechanical properties even after absorbing moisture, thus avoiding fabric caking or decreased breathability caused by wet expansion.

[0035] E yarn is a para-aramid filament yarn. The filament structure gives E yarn extremely high continuous strength, excellent abrasion resistance, and a smooth surface. Introducing E yarn into the inner layer is mainly used to further enhance the overall tensile strength, tear resistance, and durability of the inner layer fabric, forming a mechanical combination that combines rigidity and flexibility with D yarn.

[0036] It is worth noting that B-yarn, as a yarn with specific protective functions, can be used in both the outer and inner layers. Introducing B-yarn into the inner layer weave allows the silver-plated nylon and para-aramid fibers contained within it to be carried into the inner layer. The silver-plated nylon fibers in the inner layer can reflect or block residual radiant heat that has not been fully reflected through the outer layer, effectively adding a built-in heat reflection barrier. Simultaneously, the para-aramid fibers in the B-yarn further enhance the weft strength of the inner layer.

[0037] In some embodiments, the outer layer yarn includes outer layer warp yarns and outer layer weft yarns; the inner layer yarn includes inner layer warp yarns and inner layer weft yarns; the outer layer is woven with a 2-up, 1-down twill weave, and the warp and weft directions form a grid of 0.25-0.4cm in size. The outer layer yarn uses C yarn as the outer layer warp yarn and A yarn and B yarn as the outer layer weft yarns, with the outer layer weft yarns arranged in a 1:4 ratio of A yarn to B yarn. The grid yarn is A yarn. Figure 1 As shown.

[0038] In some embodiments, the inner layer is woven in a 1-up-1-down pattern, with D and E yarns as the inner layer warp yarns; the inner layer warp yarns are arranged in the pattern of 2 D yarns, 1 E yarn, 1 D yarn, 1 E yarn, 2 D yarns, and 2 E yarns; the inner layer weft yarns are B yarns, D yarns, and E yarns, with the inner layer weft yarns arranged in the pattern of 2 D yarns, 1 E yarn, 1 D yarn, 1 B yarn, 1 E yarn, 2 D yarns, 1 B yarn, 2 E yarns, 1 D yarn, 1 E yarn, and 1 B yarn. Figure 2 As shown.

[0039] In this embodiment, to achieve the optimal performance of the aforementioned material system, the fabric structure and yarn arrangement of the fabric were precisely designed. The outer and inner layers, as independent yet interconnected systems, have their warp and weft yarns configured according to specific functional logic.

[0040] For the surface fabric, a 2-up, 1-down twill weave is used. This weave was chosen primarily for two advantages: First, the twill weave creates continuous diagonal lines on the fabric surface. Its structure is looser than plain weave and more stable than satin weave, providing the fabric with good flexibility and wrinkle resistance while maintaining a certain density. Second, through precise control of process parameters, this twill weave forms clear grids with dimensions of 0.25 cm to 0.4 cm in both warp and weft directions. This macroscopic grid structure forms the physical carrier of the surface's uneven texture. Simultaneously, forest firefighting clothing is highly susceptible to scratches from branches; the 0.25-0.4 cm micro-grids can confine localized tears to individual grid points, preventing the tears from widening.

[0041] To achieve the above structure and optimize performance, C yarn is used as the surface warp yarn. This is because C yarn contains a high proportion of para-aramid fibers, giving it extremely high strength and rigidity. Using C yarn as the warp yarn allows its excellent tensile strength to withstand the main warp tension during weaving and subsequent use, ensuring fabric dimensional stability and resistance to deformation, providing a robust skeleton for the entire surface layer. A yarn and B yarn are used as the surface weft yarns, arranged alternately in a 1:4 ratio. This arrangement strategy achieves an optimized allocation of function and cost: for every one A yarn mainly composed of polyimide and meta-aramid, four B yarns mainly composed of meta-aramid and para-aramid with a slightly higher silver-plated nylon content are introduced. This ratio makes the reinforcing and reflective functions of B yarn the mainstay of the weft direction, while A yarn intermittently provides additional high-temperature resistance and reflective base points. Crucially, A yarn is designated as the grid yarn. Because yarn A has different fiber composition and shrinkage characteristics than yarn B, it stands out more effectively on the fabric surface during interlacing and subsequent finishing processes. This actively and regularly forms the aforementioned grid-like protrusions, directly shaping the textured structure. Simultaneously, the grid yarn also acts as a reinforcing rib. Due to its polyimide content and different yarn count, it maintains the grid shape when heated, preventing the fabric from shrinking drastically at high temperatures.

[0042] The inner layer fabric is woven using a 1-up, 1-down plain weave. Plain weave is the simplest and most stable of all fabric weaves, with the most warp and weft interlacing points, resulting in a tight, flat, and strong fabric structure with relatively uniform breathability. This ensures that the inner layer, as a comfortable layer close to the skin, provides a stable and reliable skin-friendly experience and basic protection.

[0043] The inner layer's yarn configuration is also meticulously arranged, using D and E yarns as the inner warp. Their arrangement follows a specific cyclic sequence: 2 D yarns, 1 E yarn, 1 D yarn, 1 E yarn, 2 D yarns, 2 E yarns. This non-uniform arrangement regularly interweaves the highly absorbent D yarns and the high-strength E yarns in the warp direction. The purpose of this design is to create an alternating gradient of mechanical and moisture-wicking properties in the warp direction. The D yarns provide the main moisture-wicking channels, while the interspersed E yarns act as reinforcing ribs, significantly improving the overall strength and abrasion resistance of the inner warp, preventing excessive wear of the D yarns due to prolonged wear or friction. Simultaneously, this arrangement breaks up stress concentration in the fabric, ensuring extremely high strength while maintaining a certain softness and dynamic drape, avoiding the stiffness of traditional protective clothing.

[0044] The inner weft layer is composed of B, D, and E yarns, following a more complex cyclical arrangement: 2 D yarns, 1 E yarn, 1 D yarn, 1 B yarn, 1 E yarn, 2 D yarns, 1 B yarn, 2 E yarns, 1 D yarn, 1 E yarn, and 1 B yarn. This design achieves multiple functional integrations: First, the continued use of D and E yarns in the weft direction interweaves with the warp system, forming a stable, moisture-wicking, and high-strength main mesh for the inner layer. Second, introducing B yarns from the surface layer as weft yarns into the inner layer allows for their regular embedding in the weft direction. On one hand, the silver-plated nylon fibers in the B yarns form a hidden reflective network within the inner layer, enabling secondary interception and reflection of residual heat radiation that has penetrated the surface layer, enhancing the overall redundancy of thermal protection. On the other hand, the high-strength para-aramid fibers in the B yarns also supplement the mechanical properties of the inner layer in the weft direction. This arrangement ensures the optimized distribution of functional fibers in three-dimensional space.

[0045] In some embodiments, the yarn count of yarn A is 48. s / 2-55 s / 2, the yarn count of B yarn is 42s, and the yarn count of C yarn is 40s. s / 2-45 s / 2; The yarn count of D yarn is 48. s / 2-50 s / 2; D yarn is made of 100% flame-retardant viscose 48s-50s yarn and 100% para-aramid staple fiber yarn 48s-50s wrapped together, with a wrapping twist of 750-850 twists / meter; E yarn is 200D with Z twist, and a twist of 220-250 twists / meter.

[0046] In this embodiment, the specific specifications and key process parameters of the key yarns constituting the fabric, namely yarn A, yarn B, yarn C, yarn D and yarn E, are precisely defined to ensure that the fabric woven from them can achieve the best balance between lightweight, mechanical properties, protective performance and wearing comfort.

[0047] First, the choice of yarn count, i.e. yarn fineness, is crucial for the three functional yarns on the surface.

[0048] By selecting a yarn configuration with varying fineness and including combinations of single yarns and ply yarns, the surface texture of the fabric can be further enhanced by the difference in diameter and thickness between different yarn counts after weaving, thereby increasing the diffuse reflection effect on radiant heat.

[0049] Furthermore, the yarn count of yarn A is set at 48 English count double-ply to 55 English count double-ply (48 English count double-ply ... s / 2 - 55 s / 2). This range is designed to give A yarn a relatively fine and uniform diameter. A finer yarn count helps A yarn, when used as a quilting yarn, to form a finer and more uniform texture on the fabric surface, while also facilitating the even distribution of functional fibers such as silver-plated nylon in the yarn. The double-ply structure provides the necessary strength and abrasion resistance, ensuring that it is not prone to breakage during weaving and use.

[0050] The B yarn is set at 42 s (42s). This specification is slightly coarser than the double-ply equivalent fineness of the A yarn, but as the main body of the surface weft yarn, the moderate yarn count gives the B yarn good coverage and crispness. This helps support the twill lattice structure of the surface layer, and because it contains silver-plated nylon and para-aramid, the moderate thickness ensures that these functional fibers have sufficient cross-sectional area to perform their reflective and reinforcing functions.

[0051] The yarn count of C yarn is set at 40-count double-ply to 45-count double-ply (40 s / 2-45 s / 2). As the outer warp yarn that bears the main tension, C yarn has a count range that is slightly coarser than or equivalent to that of A yarn. The coarser, double-ply yarn structure gives C yarn extremely high strength and rigidity, sufficient to withstand the high tension during weaving and the warp load in garment use, providing a fundamental guarantee for the stability of the outer layer structure. At the same time, this fineness range also allows it to be well-matched with A and B yarns to achieve the desired fabric density and thickness.

[0052] Secondly, the specifications and processes of the two core yarns in the inner layer directly determine the comfort and durability.

[0053] The yarn count of D yarn is set at 48 English count double ply to 50 English count double ply (48 English count double ply). s / 2-50 s / 2). This relatively fine double-ply specification is to ensure that the inner fabric woven from D yarn has a soft and delicate feel against the skin. Simultaneously, to achieve its special structure of external moisture absorption and internal strength, D yarn is prepared through a specific wrapping process: a pure 100% flame-retardant viscose short-fiber yarn with a count of 48s to 50s is used as the outer wrapping yarn, and a pure 100% para-aramid short-fiber yarn with a count of 48s to 50s is used as the core yarn, and these are combined and wrapped. The key process parameter of wrapping twist is controlled between 750 twists / meter and 850 twists / meter. If the twist is too low, the outer flame-retardant viscose yarn and the core para-aramid yarn will not bond firmly, easily causing slippage or pilling during weaving or use, affecting durability and moisture absorption efficiency; if the twist is too high, the yarn will become too stiff, affecting the softness of the fabric, and may excessively compress the outer viscose fibers, thus reducing its moisture absorption capacity. A twist of 750-850 twists / meter ensures that the yarn remains flexible and easy to process while maintaining a firm wrap and clear functional layering. This high twist design also prevents the outer flame-retardant adhesive from peeling off during frequent friction. Furthermore, it enhances the capillary effect through physical compression, allowing moisture to be conducted more quickly along the yarn axis.

[0054] E-yarn is a 200 denier (200D) para-aramid filament yarn with Z-twist, and the twist is set at 220 twists / meter to 250 twists / meter. The 200D fineness ensures sufficient strength without being overly coarse or stiff, allowing for good compatibility with D-yarn. Adding Z-twist is a standard spinning process, giving the filament a certain degree of cohesion and strength, preventing it from unraveling. The twist range of 220-250 twists / meter represents the optimal balance between enhancing yarn strength, reducing weaving hairiness, and maintaining the smooth hand feel of the filament itself, facilitating weaving. This specification of E-yarn provides excellent continuous strength and fatigue resistance for the inner layer. Simultaneously, the combination of the filament form and the specific twisting process also provides the inner layer of the fabric with extremely high dimensional stability and warp and weft breaking strength. The combination of low-twist filaments and high-twist wrapped short fiber D yarns allows the fabric to absorb impact energy through the synergistic deformation of yarns with different twists when under stress, significantly improving the tear resistance of fire-fighting clothing fabrics.

[0055] Through precise matching of the yarn specifications and twist of groups A to E above, this fabric ultimately achieved a balance between weight control, protective performance, and mechanical strength, with a unit area mass of 205 g / m². 2 -230 g / m 2 .

[0056] In some embodiments, the outer layer yarn includes outer layer warp yarn and outer layer weft yarn; the inner layer yarn includes inner layer warp yarn and inner layer weft yarn; the ratio of outer layer warp yarn to inner layer warp yarn is 1.58-1.65:1, and the ratio of outer layer weft yarn to inner layer weft yarn is 1.70-1.80:1.

[0057] In this embodiment, to achieve a precise balance between multiple performance objectives such as protection, breathability, lightweight, and comfort, a crucial limit was placed on the yarn density ratio between the outer and inner layers of the double-layer fabric structure. This ratio is an optimized parameter determined based on considerations of the interactions between the double-layer fabric in terms of heat and moisture transfer, mechanical support, and spatial structure.

[0058] Specifically, the ratio of the total density of the surface warp yarns to the total density of the inner warp yarns is controlled to be 1.58:1 to 1.65:1. This means that, per unit width, the number of warp yarns forming the surface skeleton (mainly high-strength, heat-resistant C yarns) is approximately 1.58 to 1.65 times the number of warp yarns forming the inner base (composed of moisture-absorbing D yarns and high-strength E yarns arranged in a specific ratio). This ratio range has a clear functional orientation. A higher surface warp density ensures that the surface fabric has sufficient tightness, smoothness, and structural stability. The tight warp arrangement allows the surface layer, composed of C, A, and B yarns, to form a denser and more continuous physical barrier, effectively blocking the direct intrusion of high-temperature airflow, carbon dust, and some radiant heat, while providing a uniform and solid support base for the surface's uneven structure, making it regular in shape and durable. Secondly, a higher surface warp density is also directly related to the fabric's mechanical properties, especially the warp breaking strength and tear strength, ensuring the fabric's durability in harsh environments.

[0059] Simultaneously, the ratio of the total density of the surface weft yarns to the total density of the inner weft yarns is controlled to be 1.70:1 to 1.80:1. That is, per unit length, the number of weft yarns constituting the main body of the surface layer (arranged as A yarns and B yarns in a 1:4 ratio) is approximately 1.70 to 1.80 times the number of weft yarns constituting the main body of the inner layer (arranged as B yarns, D yarns, and E yarns in a complex cycle). Setting this higher weft density ratio enhances the coverage and protective integrity of the surface layer. In fabrics, weft yarns primarily affect the transverse tightness, hand feel, and the ability to block external stimuli such as friction and radiation. The high ratio of 1.70-1.80 ensures that the surface layer also has an extremely high yarn coverage coefficient in the weft direction, allowing functional elements such as silver-plated nylon fibers to form a nearly continuous reflective layer on the fabric surface, maximizing the reflection efficiency of radiant heat. Furthermore, the tight weft arrangement combined with the twill weave further solidifies the texture of the fabric surface and enhances the overall stiffness and shape retention of the fabric.

[0060] These two ratios work synergistically to create a gradient density structure within the fabric, with a tighter outer layer and a looser inner layer. The tighter outer layer is characterized by a significantly higher warp and weft density on the surface compared to the inner layer, creating a dense, robust, and highly reflective primary protective shell. The looser inner layer is reflected in its relatively lower yarn density, providing more pore space within the inner fabric. This allows for airflow and moisture exchange, facilitating the expulsion of perspiration through the relatively loose structure of the inner layer, significantly improving breathability and reducing heat buildup. Furthermore, when the fabric is heated, it provides the necessary structural flexibility for the inner layer to expand and form insulating air chambers; and it also gives the inner layer a softer, fluffier feel, enhancing wearing comfort.

[0061] In some embodiments, the polyimide fibers, meta-aramid fibers, and para-aramid fibers are loaded with submicron-sized antibacterial particles.

[0062] To endow the forest firefighting suit fabric with durable and efficient hygienic protection capabilities, addressing the challenges of firefighters sweating during prolonged work and the harsh environment conducive to microbial growth, special functional modifications were made to the high-temperature resistant fibers constituting the core of the fabric. Specifically, at least one of polyimide fibers, meta-aramid fibers, and para-aramid fibers was loaded with submicron-sized antibacterial particles on its surface or inside.

[0063] Introducing submicron-sized antibacterial particles into fibers allows for the exposure of more active sites per unit mass of antibacterial agent due to their extremely high specific surface area, significantly increasing the contact area with microorganisms and thus significantly improving antibacterial efficiency and speed. Their tiny size allows them to be more firmly and uniformly loaded onto the fiber surface and interior through physical adsorption, chemical bonding, or blend spinning, enabling controlled and sustained release of active ingredients under conditions such as friction and sweat wetting, ensuring long-lasting antibacterial effects. At the same time, the excellent dispersibility of submicron particles in the fiber matrix effectively avoids the formation of stress concentration points, minimizing the negative impact on the mechanical properties, heat resistance, and spinnability of the main fibers, thereby ensuring that the core physical properties of the fabric are not damaged.

[0064] The active ingredients of the antibacterial particles can be selected from, but are not limited to, materials with broad-spectrum, high-efficiency, and durable antibacterial properties such as nano-silver, nano-zinc oxide, nano-titanium dioxide (modified by photocatalysis), and quaternary ammonium salt compounds. The loading process can be implemented at different stages of fiber manufacturing: for example, in the spinning solution preparation stage, the precursor of the antibacterial particles or a well-dispersed particle suspension is uniformly mixed with a polymer solution, and antibacterial masterbatch or antibacterial composite fiber is produced by wet or dry spinning; or in the finishing stage of the finished fiber, the antibacterial particles are firmly fixed to the fiber surface through impregnation, coating, graft polymerization, or other techniques. Regardless of the process used, the goal is to achieve a stable and uniform distribution of the antibacterial particles in the fiber.

[0065] In some embodiments, the bonding yarn is a core-spun yarn, wherein the core yarn, which consists of a core yarn and an outer sheath fiber, is a super-elastic nickel-titanium alloy wire, and the outer sheath fiber includes aramid 1313 and flame-retardant viscose.

[0066] This spliced ​​yarn design gives the fabric unique intelligent thermal response characteristics.

[0067] First, the core yarn uses ultra-elastic nickel-titanium alloy yarn, which has a significant shape memory effect and super elasticity. When the fabric is exposed to high temperatures in a fire, and the ambient temperature exceeds the phase transformation trigger point of the alloy, the crystal structure inside the alloy yarn undergoes a transformation from martensite to austenite. This phase transformation process is accompanied by a huge release of internal stress, manifested as the alloy yarn generating a strong contraction force, with a macroscopic tendency to strive to return to the original preset straight state. It is this characteristic of thermal contraction that provides the most fundamental driving force for pulling and reconfiguring the spatial relationship between the surface and inner layers. When away from the heat, the ultra-elastic nickel-titanium alloy core-spun yarn can quickly stretch, reducing the air cavities formed between the surface and inner layers, while also reducing the surface density, allowing hot and humid gases inside and outside to be quickly expelled. That is, when the heat source disappears and the fabric temperature drops, the alloy yarn can transform back from the austenite phase to the flexible martensite phase, making the driven deformation reversible, thereby ensuring that the fabric can reliably and persistently switch between a high-protection state and a normal comfort state.

[0068] For example, the diameter of the knotting yarn can be 0.03 mm. This ensures sufficient driving force while minimizing its adverse effects on the overall softness and weight of the fabric, allowing it to be smoothly woven into the fabric structure like conventional textile yarns. For example, the yarn count of the knotting yarn is 26s-30s. This ensures that the knotting yarn has sufficient space in its microstructure to wrap the superelastic nickel-titanium alloy core yarn, enabling it to output stable mechanical support force during thermal deformation to maintain the geometry of the topological air cavity. At the same time, this yarn count range ensures good compatibility in fineness between the knotting yarn and the warp and weft yarns of the outer and inner layers, avoiding obvious physical protrusions at the knotting position. Thus, without significantly increasing the overall weight of the fabric, it ensures the softness and wearing comfort of the fabric, while also possessing sufficient mechanical strength and structural rigidity to connect the outer and inner layers and transmit driving force.

[0069] Secondly, the outer sheath fiber of the knot yarn uses a combination of aramid 1313 (meta-aramid) and flame-retardant viscose, which provides dual protection in terms of function. For example, the outer sheath fiber is a blend of aramid 1313 and flame-retardant viscose in a specific ratio, such as 60:40 by weight. Aramid 1313 provides excellent high-temperature resistance and flame-retardant properties, protecting the internal nickel-titanium alloy wire from oxidation or performance degradation due to high temperatures; the high strength and abrasion resistance of aramid 1313 itself also significantly enhances the overall tensile strength and abrasion resistance of the knot yarn, making it less prone to damage and breakage in complex weaving processes and harsh usage scenarios. The flame-retardant viscose further improves the stability and compatibility of the knot yarn when interlacing with the inner and outer layer yarns, improves the stiffness and static electricity problems that may exist in pure aramid yarn during processing, enhances the smoothness of the wrapping process, and gives the final knot yarn better softness and weavability. Furthermore, the addition of flame-retardant adhesive maintains the consistency of the overall flame-retardant system of the yarn, and its moderate hygroscopicity also helps to control static interference during the production process.

[0070] In the design of core-spun yarn that combines superelastic nickel-titanium alloy wire with an aramid flame-retardant outer layer, the high-temperature resistant outer fiber layer physically isolates the metal core from direct contact with the external fire environment. Simultaneously, it ensures that the bonding yarn is perfectly compatible with the surrounding fabric matrix in terms of appearance, feel, and chemical properties. More importantly, this outer fiber layer acts as an efficient intermediary for force and heat transfer. It can evenly and reliably transfer the strong axial shrinkage force generated by the thermal shrinkage of the internal alloy wire to the outer and inner warp yarns interwoven with it, thereby driving the entire fabric structure to deform according to a predetermined pattern.

[0071] By introducing a bonding yarn containing a nickel-titanium alloy core between the outer and inner layers, the fabric transforms from passive insulation to active defense. Under the high temperatures of a fire, the bonding yarn deforms, creating a predetermined space between the originally tightly fitted outer and inner layers. Due to the extremely low thermal conductivity of air, this dynamically generated interlayer gap effectively blocks the penetration of heat conduction and radiation. Combined with the aforementioned surface reflection and inner layer moisture absorption functions, this significantly enhances the thermal safety boundary for firefighters in extreme environments.

[0072] In some embodiments, the outer and inner layers are joined by bonding yarns to form a pentagonal nested with two rhombuses in a topological structure; the pentagonal structure generates an expansion cavity when heated, and the rhombus structure forms a support and traction point inside the cavity to prevent the fabric from collapsing when heated, such as... Figure 3 As shown.

[0073] The fabric in this embodiment connects the outer and inner layers using knotting yarns, thereby creating a unique topological structure where a pentagon nests two rhombuses between the two layers. This topological structure utilizes the temperature-sensitive deformation characteristics of the ultra-elastic nickel-titanium alloy wires in the knotting yarns to achieve a dynamic transformation of the fabric from a planar weave to a three-dimensional protective structure.

[0074] The design logic of this topology lies in achieving a scientific balance between expansion space and support strength. Specifically, the pentagonal structure serves as the main deformation unit when the fabric is heated. When the ambient temperature rises and triggers the shape memory effect of the knotting yarns, the knotting yarns within the pentagonal structure area drive the inner and outer layers away from each other, thereby generating periodically distributed expansion air cavities within the fabric. Due to the extremely low thermal conductivity of air, these dynamically generated air cavities form a dense insulating air wall, significantly blocking the conduction of external radiant heat to the inner layers.

[0075] Meanwhile, the two rhombus-shaped structures nested within the pentagon serve as core supports and displacement constraints. During the expansion of the air cavity, the joints of the rhombus-shaped structures form internal support and traction points. These traction points, like cables in a building structure, limit excessive displacement between the inner and outer layers, preventing the air cavity from collapsing or becoming unstable due to external pressure (such as wind pressure or limb compression during a firefighter's run). This nested rhombus structure ensures that the air cavity has extremely high physical structural strength after thermal expansion, allowing the fabric to maintain a stable thermal insulation gap even in extreme high-temperature environments, preventing the surface high-temperature fabric from directly contacting the skin and causing burns.

[0076] This pentagonal-nested rhombus topology achieves a quantitative improvement in protective effectiveness. Compared to traditional uniform bonding methods, the non-uniform topological space of this design can accommodate more still air, significantly improving the fabric's radiant heat protection value (RPP). Simultaneously, the traction effect of the rhombus structure ensures the fabric's flatness and structural integrity after heat deformation, not only solving the technical problems of traditional protective clothing easily clinging to the body and collapsing after heating, but also achieving intelligent and dynamic defense against the intense radiation environment of forest fires.

[0077] In some embodiments, the topology of a pentagon nested within two rhombuses is achieved through the following connection method.

[0078] The outer and inner layers are interwoven and joined at multiple joint points by connecting yarns, thus forming a topological structure; the outer layer yarns include the outer layer warp yarns, and the inner layer yarns include the inner layer warp yarns; the joint point is the position where the connecting yarn intersects and is fixed with the outer layer warp yarns and the inner layer warp yarns; The joints are arranged according to a predetermined spatial distribution pattern to form a joint loop; a complete joint loop includes joints formed by seven weft-direction joint yarns.

[0079] like Figure 4As shown, the first splicing yarn forms four first splicing points (1, 1-2, 1-3, 1-4) with the outer warp yarn and the inner warp yarn. The distances between adjacent first splicing points are 0.8-0.9cm, 0.4-0.5cm, and 0.8-0.9cm, respectively. The distance between the last first splicing point (1-4) in this splicing cycle and the first first splicing point in the adjacent cycle along the warp direction (not shown in the figure) is 0.4-0.5cm. The second joining yarn forms four second joining points (2, 2-2, 2-3, 2-4) with the outer and inner warp yarns. The distances between adjacent second joining points are 1.2-1.3cm, 0.2-0.3cm, and 1.2-1.3cm, respectively. The distance between the last second joining point (2-4) in this joining cycle and the first second joining point (not shown in the figure) in the adjacent cycle along the warp direction is 0.2-0.3cm. The third knot yarn forms three third knot points (3, 3-2, 3-3) with the outer warp yarn and the inner warp yarn. The distance between adjacent third knot points is 1.5-1.6cm. The distance between the last third knot point (3-3) in this knot cycle and the first third knot point in the adjacent cycle along the warp direction (not shown in the figure) is 1.5-1.6cm. The fourth knot yarn forms two fourth knot points (4, 4-1) with the outer warp yarn and the inner warp yarn. The distance between adjacent fourth knot points is 1.5-1.6cm, and the distance between the last fourth knot point in this knot cycle and the first fourth knot point in the adjacent cycle along the warp direction is 1.5-1.6cm. The fifth knot yarn forms three fifth knot points (5, 5-1, 5-2) with the outer warp yarn and the inner warp yarn. The arrangement of the fifth knot points is the same as that of the third knot point. The sixth knot yarn forms four sixth knot points (6, 6-1, 6-2, 6-3) with the outer warp yarn and the inner warp yarn. The arrangement of the sixth knot points is the same as that of the second knot points. The seventh knot yarn forms four seventh knot points (7, 7-1, 7-2, 7-3) with the outer warp yarn and the inner warp yarn. The arrangement of the seventh knot points is the same as that of the first knot point.

[0080] In this embodiment, the aforementioned pentagonal nested with two rhombus topology is achieved through the following connection method. The outer and inner layers of the fabric are interwoven and connected at multiple connection points by connecting yarns. The connection point is defined as the spatial position where the connecting yarn intersects, interweaves, and is fixed with the outer and inner layer yarns during the shuttle process.

[0081] To construct a stable three-dimensional air cavity, these joints are arranged according to a predetermined spatial pattern, forming a complete joint loop. This loop is completed collaboratively by seven joint yarns arranged along the weft direction (the first to the seventh joint yarns). By controlling the spacing between the hanging points of each joint yarn in the warp and weft directions, a non-uniform distribution of interlayer constraint force is achieved.

[0082] The first joining yarn forms four first joining points with the outer and inner warp yarns. In the weft direction, the distances between adjacent first joining points are set to 0.8-0.9 cm, 0.4-0.5 cm, and 0.8-0.9 cm respectively; while in the warp direction, the distance between the last first joining point in this joining cycle and the first first joining point in the adjacent cycle along the warp direction is 0.4-0.5 cm. This tight boundary arrangement provides longitudinal edge support for the pentagonal structure.

[0083] The second knot yarn forms four second knot points, with the spacing between adjacent second knot points being 1.2-1.3cm, 0.2-0.3cm, and 1.2-1.3cm respectively, and the cycle spacing being 0.2-0.3cm.

[0084] The third and fifth knotting yarns are arranged in the same way, each forming three knots, with adjacent spacing and cycle spacing of 1.5-1.6cm. This large-span spacing design provides ample expansion space for the central area of ​​the pentagonal structure.

[0085] The fourth knot yarn serves as the central axis of symmetry, forming two fourth knot points with adjacent spacing and loop spacing of 1.5-1.6 cm. The fourth knot yarn works in conjunction with the third and fifth knot yarns on the side wings to interweave two rhomboid tension frames inside the pentagonal air cavity.

[0086] The arrangement of the sixth and seventh knot yarns corresponds to that of the second and first knot yarns, respectively, thus completing a complete topological cycle symmetrical about the fourth knot yarn.

[0087] Through precise and asymmetrical joint control of the seven connecting yarns, this embodiment establishes a complex mechanical balance system between the outer and inner layers, ensuring the reliability and repeatability of the adaptive thermal protection function. When the superelastic nickel-titanium alloy wires in the connecting yarns are deformed by heat, due to the different constraint torques at each joint, the third to fifth connecting yarn areas with larger spacing will rapidly bulge outward to form an expansion air cavity with a pentagonal outline, while the first and second connecting yarns with shorter spacing and regular distribution, through the pulling force formed by high-frequency jointing, lock the rhomboid structure inside the air cavity. This process not only ensures the geometric accuracy of air cavity formation, but also ensures that the fabric can form a continuous and stable dynamic air insulation wall after heat deformation through cyclical and progressive spacing control, effectively solving the problem of thermal insulation failure caused by thermal collapse of protective clothing under large-area heat radiation.

[0088] The following describes a method 20 for preparing the radiant heat protective forest firefighting suit fabric according to an embodiment of this application. The outer layer yarn of the radiant heat protective forest firefighting suit fabric includes outer layer warp yarns and outer layer weft yarns; the inner layer yarn includes inner layer warp yarns and inner layer weft yarns. This preparation method 20 is achieved through steps S1-S4.

[0089] S1. Yarn Preparation. In this step, the outer layer yarn, inner layer yarn, and bonding yarn are prepared. The outer layer yarn includes yarn A, yarn B, and yarn C, and the inner layer yarn includes yarn D and yarn E. For example, the outer layer yarn is woven from yarns A, B, and C; yarn A includes 15%-25% polyimide fiber, 60%-70% meta-aramid fiber, 0%-15% flame-retardant viscose, and 2%-6% silver-plated nylon fiber; yarn B includes 10%-22% para-aramid fiber, 75%-85% meta-aramid fiber, and 3%-8% silver-plated nylon fiber; yarn C includes 30%-42% para-aramid fiber, 52%-65% meta-aramid fiber, and 3%-6% silver-plated nylon fiber. The inner layer yarn is woven from yarns B, D, and E; yarn D is a wrapped yarn, composed of 100% para-aramid staple fiber yarn and 100% flame-retardant viscose staple fiber yarn, with the flame-retardant viscose staple fiber yarn located on the outer layer of yarn D; yarn E is para-aramid filament. For example, yarn A has a count of 48. s / 2-55 s / 2, the yarn count of B yarn is 42s, and the yarn count of C yarn is 40s. s / 2-45 s / 2; The yarn count of D yarn is 48. s / 2-50 s / 2; D yarn is made of 100% flame-retardant viscose 48s-50s yarn and 100% para-aramid staple fiber yarn 48s-50s wrapped together, with a wrapping twist of 750-850 twists / meter; E yarn is 200D with Z twist, and a twist of 220-250 twists / meter.

[0090] S2. Pre-weaving preparation. In this step, the prepared yarn undergoes pre-weaving treatment. First, based on the fabric weight and yarn count, the total number of warp ends is calculated separately for the surface warp and inner warp according to their arrangement ratio (e.g., 1.58-1.65:1). Next, warping is performed. The surface warp (e.g., C yarn) and inner warp (e.g., D and E yarns arranged in a predetermined ratio) are warped separately to form surface warp beams and inner warp beams. Then, the surface warp beams and inner warp beams are combined into surface warp beams and inner warp beams using a sizing machine. Next, sizing is performed. The surface warp (e.g., C yarn) is sized to enhance its abrasion resistance and strength, adapting to high-tension weaving. Finally, heddle and reed threading is performed. Based on the designed fabric weave diagram (e.g., the outer layer is a 2-up-1-down twill weave and the inner layer is a 1-up-1-down plain weave) and the warp and weft density configuration and cycle of the outer and inner layers, the outer layer warp yarns and the inner layer warp yarns are threaded into different heddle frames using the straight-thread method, and the threaded yarns are then threaded onto the reed to complete the pre-weaving preparation.

[0091] S3. Weaving. In this step, the warp beam processed in step S2 is installed on the loom, and parameters are set and weaving begins. First, a rapier double warp beam loom is used, and the back beam is set to the middle back beam position, with the lower back beam height adjusted to 1040mm. Next, the outer warp beam is installed as the upper warp beam, and the inner warp beam as the lower warp beam. Then, the loom tension parameters are set. The tension of the upper warp beam (outer warp yarns) is controlled at 600-750MV, and the tension of the lower warp beam (inner warp yarns) is controlled at 100-150MV. Finally, the weaving parameters are controlled (the ratio of outer weft yarns to inner weft yarns is 1.70-1.80:1), and weaving is performed according to the designed weft yarn arrangement cycle. For the outer layer weft yarn, weft yarns A and B are alternately introduced in a 1:4 ratio. For the inner layer weft yarn, weft yarns are alternately introduced in a predetermined complex cycle (e.g., 2 D yarns, 1 E yarn, 1 D yarn, 1 B yarn, 1 E yarn, 2 D yarns, 1 B yarn, 2 E yarns, 1 D yarn, 1 E yarn, 1 B yarn). For the knotted weft yarn, the knotted yarn is used as a special weft yarn and introduced in a predetermined knotted cycle (e.g., every 7 weft yarns form a knotted cycle, controlling the distance between its interlacing points with the outer and inner layer warp yarns to form a pentagonal nested with two rhombus topological structures), thereby connecting the outer and inner layers into a whole.

[0092] S4. Finishing. In this step, the greige fabric obtained from step S3 is finished as follows to obtain the finished fabric. First, desizing is performed using desizing enzymes to remove the sizing applied to the warp yarns during weaving. Next, washing is performed to remove stains and desizing enzymes from the fabric surface, making the fabric clean. Then, waterproofing is performed: the fabric is treated with a durable waterproofing process. Finally, stretching and setting are performed: under appropriate temperature and tension, the fabric is stretched to a specified width (e.g., 155cm) and its dimensions are stabilized, ultimately obtaining a finished fabric with a unit area mass of 205 g / m²-230 g / m².

[0093] Unless otherwise specified, distance in this application refers to the physical distance between adjacent nodes.

[0094] The specific implementation method is described below.

[0095] Example 1 The yarn composition of a radiant heat protective forest firefighting suit fabric is as follows: the outer layer yarn A consists of 15% polyimide fiber, 65% meta-aramid fiber, 15% flame-retardant viscose, and 5% silver-plated nylon fiber, with a yarn count of 50. s / 2; Yarn B consists of 12% para-aramid, 85% meta-aramid, and 5% silver-plated nylon fiber, with a yarn count of 42s; Yarn C consists of 35% para-aramid, 62% meta-aramid, and 3% nylon-based conductive fiber, with a yarn count of 45s. s / 2. The inner layer D is made of 100% para-aramid staple yarn 50s and 100% flame-retardant viscose staple yarn 50s, with a twist of 800 twists / meter and a yarn count of 50. s / 2; Inner layer E yarn: 100% para-aramid filament, 200D, with Z-twist, twist of 250 twists / meter. The bonding yarn is made of 0.03mm diameter super-elastic nickel-titanium alloy wire and aramid 1313 accounting for 60%, flame retardant viscose accounting for 40%, core-spun together, with a bonding yarn count of 28s.

[0096] The fabric has a unit area mass of 205 g / cm², and its specifications are 420 threads / 10cm × 425 threads / 10cm, with a length of 155cm. The ratio of surface warp yarns to inner warp yarns is 1.61:1, and the ratio of surface weft yarns to inner weft yarns is 1.75:1. The surface and inner layers of the fabric are connected by knotted yarns, forming an inner pentagon with two nested rhombuses. The surface fabric uses a 2-up-1-down twill weave, with a 0.25cm grid in both warp and weft directions. The warp of the surface fabric uses C yarn, and the weft uses A and B yarns, with the ratio of A yarns to B yarns arranged in a 1:4 ratio. The grid yarn is A yarn.

[0097] The inner layer fabric has a 1-up, 1-down weave structure. The inner layer warp yarns are D yarns and E yarns. The arrangement ratio of D yarns to E yarns is 2 D yarns, 1 E yarn, 1 D yarn, 1 E yarn, 2 D yarns, and 2 E yarns. The inner layer weft yarns are B yarns, D yarns, and E yarns, arranged in the following order: 2 D yarns, 1 E yarn, 1 D yarn, 1 B yarn, 1 E yarn, 2 D yarns, 1 B yarn, 2 E yarns, 1 D yarn, 1 E yarn, and 1 B yarn. This constitutes one cycle.

[0098] The double-layer fabric requires 62 warp yarns for a complete weft yarn cycle and a total of 96 weft yarns for a complete weft yarn cycle.

[0099] The first joining yarn forms four first joining points with the outer and inner warp yarns. The distances between adjacent first joining points are 0.8 cm, 0.4 cm, and 0.8 cm, respectively. The distance between the last first joining point in this joining cycle and the first first joining point in the adjacent cycle along the warp direction is 0.4 cm. The second joining yarn forms four second joining points with the outer and inner warp yarns. The distances between adjacent second joining points are 1.2 cm, 0.2 cm, and 1.2 cm, respectively. The distance between the last second joining point in this joining cycle and the first second joining point in the adjacent cycle along the warp direction is 0.2 cm. The third joining yarn forms three third joining points with the outer and inner warp yarns. The distance between adjacent third joining points is 1.5 cm, and the distance between the last third joining point in this joining cycle and the first third joining point in the adjacent cycle along the warp direction is 1.5 cm. cm; the fourth knot yarn forms two fourth knot points with the outer and inner warp yarns, with a distance of 1.5 cm between adjacent fourth knot points, and the distance between the last fourth knot point in this knot cycle and the first fourth knot point in the adjacent cycle along the warp direction is 1.5 cm; the fifth knot yarn forms three fifth knot points with the outer and inner warp yarns, and the arrangement of the fifth knot points is the same as that of the third knot point; the sixth knot yarn forms four sixth knot points with the outer and inner warp yarns, and the arrangement of the sixth knot points is the same as that of the second knot point; the seventh knot yarn forms four seventh knot points with the outer and inner warp yarns, and the arrangement of the seventh knot points is the same as that of the first knot point. This is a complete knot cycle.

[0100] The yarn is warped, sizing, and threaded through heddles and reeds before being woven on a double-beam rapier loom. A back beam is used, with a lower back beam height of 1040mm. The upper beam consists of the surface yarn, with tension controlled at 650MV, and the lower beam tension is controlled at 130MV. The woven fabric undergoes finishing processes, including desizing, waterproofing, and stretching to achieve the finished product.

[0101] Example 2 The yarn composition of a radiant heat protective forest firefighting suit fabric is as follows: the outer layer yarn A is made of polyimide fiber, accounting for 20%; meta-aramid accounts for 65%; flame-retardant viscose accounts for 13%; silver-plated nylon fiber accounts for 2%; and the yarn count is 52. s / 2; Yarn B uses 17% para-aramid, 75% meta-aramid, and 8% silver-plated nylon fiber, with a yarn count of 42s; Yarn C uses 42% para-aramid, 55% meta-aramid, and 3% silver-plated nylon fiber, with a yarn count of 42s. s / 2. The inner layer D is made of 100% para-aramid staple yarn 50s and 100% flame-retardant viscose staple yarn 50s, with a twist of 800 twists / meter and a yarn count of 48. s / 2; Inner layer E yarn: 100% para-aramid filament, 200D, with Z-twist, twist of 250 twists / meter. The bonding yarn is made of 0.03mm diameter super-elastic nickel-titanium alloy wire and aramid 1313 accounting for 60%, flame retardant viscose accounting for 40%, core-spun together, with a bonding yarn count of 28s.

[0102] The fabric has a unit area mass of 215 g / cm², and its specifications are 430 threads / 10cm × 448 threads / 10cm, with a length of 155cm. The ratio of surface warp yarns to inner warp yarns is 1.58:1, and the ratio of weft surface warp yarns to inner warp yarns is 1.70:1. The surface and inner layers of the fabric are connected by knotted yarns, forming an inner pentagon with two nested rhombuses. The outer fabric uses a 2-up, 1-down twill weave, with a 0.35cm grid in both warp and weft directions. The warp of the outer fabric uses C yarn, and the weft uses A and B yarns, with the ratio of A yarn to B yarn arranged in 1:4. The grid yarn is A yarn. The inner fabric uses a 1-up, 1-down weave, with D and E yarns as the warp yarns. The ratio of D yarns to E yarns is 2 D yarns, 1 E yarn, 1 D yarn, 1 E yarn, 2 D yarns, and 2 E yarns. The weft of the inner fabric uses B yarns, D yarns, and E yarns, arranged in the following pattern: 2 D yarns, 1 E yarn, 1 D yarn, 1 B yarn, 1 E yarn, 2 D yarns, 1 B yarn, 2 E yarns, 1 D yarn, 1 E yarn, and 1 B yarn. This completes one cycle.

[0103] The double-layer fabric requires 60 warp yarns for a complete weft yarn cycle and a total of 92 weft yarns for a complete weft yarn cycle.

[0104] The first joining yarn forms four first joining points with the outer and inner warp yarns. The distances between adjacent first joining points are 0.85 cm, 0.45 cm, and 0.85 cm, respectively. The distance between the last first joining point in this joining cycle and the first first joining point in the adjacent cycle along the warp direction is 0.45 cm. The second joining yarn forms four second joining points with the outer and inner warp yarns. The distances between adjacent second joining points are 1.25 cm, 0.25 cm, and 1.25 cm, respectively. The distance between the last second joining point in this joining cycle and the first second joining point in the adjacent cycle along the warp direction is 0.25 cm. The third joining yarn forms three third joining points with the outer and inner warp yarns. The distance between adjacent third joining points is 1.55 cm, and the distance between the last third joining point in this joining cycle and the first third joining point in the adjacent cycle along the warp direction is 1.55 cm. cm; the fourth knot yarn forms two fourth knot points with the outer and inner warp yarns, with a distance of 1.55 cm between adjacent fourth knot points, and the distance between the last fourth knot point in this knot cycle and the first fourth knot point in the adjacent cycle along the warp direction is 1.55 cm; the fifth knot yarn forms three fifth knot points with the outer and inner warp yarns, and the arrangement of the fifth knot points is the same as that of the third knot point; the sixth knot yarn forms four sixth knot points with the outer and inner warp yarns, and the arrangement of the sixth knot points is the same as that of the second knot point; the seventh knot yarn forms four seventh knot points with the outer and inner warp yarns, and the arrangement of the seventh knot points is the same as that of the first knot point. This is a complete knot cycle.

[0105] The yarn is warped, sizing, and threaded through heddles and reeds before being woven on a double-beam rapier loom. A back beam is used, with a lower back beam height of 1030mm. The upper beam consists of the surface yarn, with tension controlled at 600MV, and the lower beam tension at 150MV. The woven fabric undergoes finishing processes including desizing, waterproofing, and stretching to achieve the final product.

[0106] Example 3 The yarn composition of a radiation heat protection forest fire fighting suit fabric is as follows: the outer layer yarn A contains 25% polyimide fiber, 70% meta-aramid fiber, and 5% silver-plated nylon fiber, with a yarn count of 55. s / 2; Yarn B uses 21% para-aramid, 75% meta-aramid, and 4% silver-plated nylon fiber, with a yarn count of 42s; Yarn C uses 41% para-aramid, 55% meta-aramid, and 4% silver-plated nylon fiber, with a yarn count of 45s. s / 2. The inner layer D is made of 100% para-aramid staple yarn 50s and 100% flame-retardant viscose staple yarn 50s, with a twist of 800 twists / meter and a yarn count of 48. s / 2; Inner layer E yarn: 100% para-aramid filament, 200D, with Z-twist, twist of 260 twists / meter. The bonding yarn is made of 0.03mm diameter super-elastic nickel-titanium alloy wire and aramid 1313 accounting for 60%, flame retardant viscose accounting for 40%, core-spun together, with a bonding yarn count of 28s.

[0107] The fabric has a unit area mass of 208 g / cm², and its specifications are 452 threads / 10cm × 440 threads / 10cm, with a length of 155cm. The ratio of surface warp yarns to inner warp yarns is 1.65:1, and the ratio of weft surface warp yarns to inner warp yarns is 1.80:1. The surface and inner layers of the fabric are connected by knotted yarns, forming an internal pentagon with two nested rhombuses. The outer fabric uses a 2-up, 1-down twill weave, with a 0.4cm grid formed in both warp and weft directions. The warp of the outer fabric uses C yarn, and the weft uses A and B yarns, with the ratio of A yarn to B yarn arranged in a 1:4 ratio. The grid yarn is A yarn. The inner fabric uses a 1-up, 1-down weave, with D and E yarns used in the warp. The ratio of D yarns to E yarns is 2 D yarns, 1 E yarn, 1 D yarn, 1 E yarn, 2 D yarns, and 2 E yarns. The weft of the inner fabric uses B yarns, D yarns, and E yarns, arranged in the following pattern: 2 D yarns, 1 E yarn, 1 D yarn, 1 B yarn, 1 E yarn, 2 D yarns, 1 B yarn, 2 E yarns, 1 D yarn, 1 E yarn, and 1 B yarn. This completes one cycle.

[0108] The double-layer fabric requires 68 yarns for a complete warp yarn cycle and a total of 100 weft yarns for a complete weft yarn cycle.

[0109] The first joining yarn forms four first joining points with the outer and inner warp yarns. The distances between adjacent first joining points are 0.9 cm, 0.5 cm, and 0.9 cm, respectively. The distance between the last first joining point in this joining cycle and the first first joining point in the adjacent cycle along the warp direction is 0.5 cm. The second joining yarn forms four second joining points with the outer and inner warp yarns. The distances between adjacent second joining points are 1.3 cm, 0.3 cm, and 1.3 cm, respectively. The distance between the last second joining point in this joining cycle and the first second joining point in the adjacent cycle along the warp direction is 0.3 cm. The third joining yarn forms three third joining points with the outer and inner warp yarns. The distance between adjacent third joining points is 1.6 cm, and the distance between the last third joining point in this joining cycle and the first third joining point in the adjacent cycle along the warp direction is 1.6 cm. cm; the fourth knot yarn forms two fourth knot points with the outer and inner warp yarns, with a distance of 1.6 cm between adjacent fourth knot points, and the distance between the last fourth knot point in this knot cycle and the first fourth knot point in the adjacent cycle along the warp direction is 1.6 cm; the fifth knot yarn forms three fifth knot points with the outer and inner warp yarns, and the arrangement of the fifth knot points is the same as that of the third knot point; the sixth knot yarn forms four sixth knot points with the outer and inner warp yarns, and the arrangement of the sixth knot points is the same as that of the second knot point; the seventh knot yarn forms four seventh knot points with the outer and inner warp yarns, and the arrangement of the seventh knot points is the same as that of the first knot point. This is a complete knot cycle.

[0110] The yarn is warped, sizing, and threaded through heddles and reeds before being woven on a double-beam rapier loom. A back beam is used, with a lower back beam height of 1050mm. The upper beam consists of the surface yarn, with tension controlled at 670MV, and the lower beam tension is controlled at 140MV. The woven fabric undergoes finishing processes including desizing, waterproofing, and stretching to achieve the final product.

[0111] Example 4 The yarn composition of a radiant heat protective forest firefighting suit fabric is as follows: the outer layer yarn A contains 25% polyimide fiber, 70% meta-aramid fiber, 6% flame-retardant viscose, and 5% silver-plated nylon fiber, with a yarn count of 50. s / 2; Yarn B consists of 17% para-aramid, 77% meta-aramid, and 6% silver-plated nylon fiber, with a yarn count of 42s; Yarn C consists of 40% para-aramid, 56% meta-aramid, and 4% silver-plated nylon fiber, with a yarn count of 42s. s / 2. The inner layer D is made of 100% para-aramid staple yarn 48s and 100% flame-retardant viscose staple yarn 48s, with a twist of 800 twists / meter and a yarn count of 48. s / 2; Inner layer E yarn: 100% para-aramid filament, 200D, with Z-twist, twist of 260 twists / meter. The bonding yarn is made of 0.03mm diameter super-elastic nickel-titanium alloy wire and aramid 1313 accounting for 60%, flame retardant viscose accounting for 40%, core-spun together, with a bonding yarn count of 28s.

[0112] The fabric has a unit area mass of 220 g / cm², and its specifications are 430 threads / 10cm × 445 threads / 10cm, with a length of 155cm. The ratio of surface warp yarns to inner warp yarns is 1.63:1, and the ratio of weft surface warp yarns to inner warp yarns is 1.72:1. The surface and inner layers of the fabric are connected by knotted yarns, forming an inner pentagon with two nested rhombuses. The outer fabric uses a 2-up, 1-down twill weave, with a 0.35cm grid in both warp and weft directions. The warp of the outer fabric uses C yarn, and the weft uses A and B yarns, with the ratio of A yarn to B yarn arranged in 1:4. The grid yarn is A yarn. The inner fabric uses a 1-up, 1-down weave, with D and E yarns as the warp yarns. The ratio of D yarns to E yarns is 2 D yarns, 1 E yarn, 1 D yarn, 1 E yarn, 2 D yarns, and 2 E yarns. The weft of the inner fabric uses B yarns, D yarns, and E yarns, arranged in the following pattern: 2 D yarns, 1 E yarn, 1 D yarn, 1 B yarn, 1 E yarn, 2 D yarns, 1 B yarn, 2 E yarns, 1 D yarn, 1 E yarn, and 1 B yarn. This completes one cycle.

[0113] The double-layer fabric requires 60 warp yarns for a complete weft yarn cycle and a total of 90 weft yarns for a complete weft yarn cycle.

[0114] The first joining yarn forms four first joining points with the outer and inner warp yarns. The distances between adjacent first joining points are 0.8 cm, 0.5 cm, and 0.8 cm, respectively. The distance between the last first joining point in this joining cycle and the first first joining point in the adjacent cycle along the warp direction is 0.5 cm. The second joining yarn forms four second joining points with the outer and inner warp yarns. The distances between adjacent second joining points are 1.2 cm, 0.2 cm, and 1.2 cm, respectively. The distance between the last second joining point in this joining cycle and the first second joining point in the adjacent cycle along the warp direction is 0.2 cm. The third joining yarn forms three third joining points with the outer and inner warp yarns. The distance between adjacent third joining points is 1.5 cm, and the distance between the last third joining point in this joining cycle and the first third joining point in the adjacent cycle along the warp direction is 1.5 cm. cm; the fourth knot yarn forms two fourth knot points with the outer and inner warp yarns, with a distance of 1.5 cm between adjacent fourth knot points, and the distance between the last fourth knot point in this knot cycle and the first fourth knot point in the adjacent cycle along the warp direction is 1.5 cm; the fifth knot yarn forms three fifth knot points with the outer and inner warp yarns, and the arrangement of the fifth knot points is the same as that of the third knot point; the sixth knot yarn forms four sixth knot points with the outer and inner warp yarns, and the arrangement of the sixth knot points is the same as that of the second knot point; the seventh knot yarn forms four seventh knot points with the outer and inner warp yarns, and the arrangement of the seventh knot points is the same as that of the first knot point. This is a complete knot cycle.

[0115] The yarn is warped, sizing, and threaded through heddles and reeds before being woven on a double-beam rapier loom. A back beam is used, with a lower back beam height of 1030mm. The upper beam consists of the surface yarn, with tension controlled at 660MV, and the lower beam tension is controlled at 140MV. The woven fabric undergoes finishing processes including desizing, waterproofing, and stretching to achieve the final product.

[0116] Example 5 The yarn composition of a radiation heat protection forest fire fighting suit fabric is as follows: the outer layer yarn A contains 17% polyimide fiber, 70% meta-aramid fiber, 9% flame-retardant viscose, and 6% silver-plated nylon fiber, with a yarn count of 48. s / 2; Yarn B uses 17% para-aramid, 75% meta-aramid, and 8% silver-plated nylon fiber, with a yarn count of 42s; Yarn C uses 38% para-aramid, 58% meta-aramid, and 4% silver-plated nylon fiber, with a yarn count of 40s. s / 2. The inner layer D is made of 100% para-aramid staple yarn 50s and 100% flame-retardant viscose staple yarn 50s, with a twist of 800 twists / meter and a yarn count of 50. s / 2; Inner layer E yarn: 100% para-aramid filament, 200D, with Z-twist, twist of 250 twists / meter. The bonding yarn is made of 0.03mm diameter super-elastic nickel-titanium alloy wire and aramid 1313 accounting for 60%, flame retardant viscose accounting for 40%, core-spun together, with a bonding yarn count of 28s.

[0117] The fabric has a unit area mass of 230 g / cm², and its specifications are 425 threads / 10cm × 452 threads / 10cm, with a length of 155cm. The ratio of surface warp yarns to inner warp yarns is 1.60:1, and the ratio of weft surface warp yarns to inner warp yarns is 1.72:1. The surface and inner layers of the fabric are connected by knotted yarns, forming an internal pentagon with two nested rhombuses. The outer fabric uses a 2-up, 1-down twill weave, with a 0.4cm grid formed in both warp and weft directions. The warp of the outer fabric uses C yarn, and the weft uses A and B yarns, with the ratio of A yarn to B yarn arranged in a 1:4 ratio. The grid yarn is A yarn. The inner fabric uses a 1-up, 1-down weave, with D and E yarns used in the warp. The ratio of D yarns to E yarns is 2 D yarns, 1 E yarn, 1 D yarn, 1 E yarn, 2 D yarns, and 2 E yarns. The weft of the inner fabric uses B yarns, D yarns, and E yarns, arranged in the following pattern: 2 D yarns, 1 E yarn, 1 D yarn, 1 B yarn, 1 E yarn, 2 D yarns, 1 B yarn, 2 E yarns, 1 D yarn, 1 E yarn, and 1 B yarn. This completes one cycle.

[0118] The double-layer fabric requires 70 warp yarns for a complete weft yarn cycle and a total of 98 weft yarns for a complete weft yarn cycle.

[0119] The first joining yarn forms four first joining points with the outer and inner warp yarns. The distances between adjacent first joining points are 0.85 cm, 0.4 cm, and 0.8 cm, respectively. The distance between the last first joining point in this joining cycle and the first first joining point in the adjacent cycle along the warp direction is 0.4 cm. The second joining yarn forms four second joining points with the outer and inner warp yarns. The distances between adjacent second joining points are 1.25 cm, 0.3 cm, and 1.25 cm, respectively. The distance between the last second joining point in this joining cycle and the first second joining point in the adjacent cycle along the warp direction is 0.3 cm. The third joining yarn forms three third joining points with the outer and inner warp yarns. The distance between adjacent third joining points is 1.5 cm, and the distance between the last third joining point in this joining cycle and the first third joining point in the adjacent cycle along the warp direction is 1.5 cm. cm; the fourth knot yarn forms two fourth knot points with the outer and inner warp yarns, with a distance of 1.5 cm between adjacent fourth knot points, and the distance between the last fourth knot point in this knot cycle and the first fourth knot point in the adjacent cycle along the warp direction is 1.5 cm; the fifth knot yarn forms three fifth knot points with the outer and inner warp yarns, and the arrangement of the fifth knot points is the same as that of the third knot point; the sixth knot yarn forms four sixth knot points with the outer and inner warp yarns, and the arrangement of the sixth knot points is the same as that of the second knot point; the seventh knot yarn forms four seventh knot points with the outer and inner warp yarns, and the arrangement of the seventh knot points is the same as that of the first knot point. This is a complete knot cycle.

[0120] The yarn is warped, sizing, and threaded through heddles and reeds before being woven on a double-beam rapier loom. A back beam is used, with a lower back beam height of 1040mm. The upper beam consists of the surface yarn, with tension controlled at 750MV, and the lower beam tension is controlled at 150MV. The woven fabric undergoes finishing processes including desizing, waterproofing, and stretching to achieve the final product.

[0121] In Examples 1-5, the polyimide fibers, meta-aramid fibers, and para-aramid fibers were all loaded with submicron-sized antibacterial particles.

[0122] Example 6 The only difference from Example 5 is that the inner warp yarns and the outer warp yarns are joined by a knotting yarn every two warp yarns, thus not forming a pentagonal nested with two rhombus topology.

[0123] Example 7 The only difference from Example 5 is that no antibacterial particles were loaded on the polyimide fiber, meta-aramid fiber, and para-aramid fiber.

[0124] Comparative Example 1 The only difference from Example 5 is that none of the yarns contain silver-plated nylon fibers. After removing the silver-plated nylon fibers, the proportions of the other components are increased proportionally to make their total 100%.

[0125] Comparative Example 2 The only difference from Example 5 is that the inner layer yarn uses only E yarn. The E yarn is made of 100% para-aramid filament with Z-twist, 210 twists / meter. In Example 5, both D yarn and B yarn are replaced with E yarn.

[0126] Comparative Example 3 This comparative example illustrates the crucial role of the textured structure formed by interwoven yarns in thermal protection performance. The surface yarn does not use the three different yarns A, B, and C from Example 5, but is instead equivalent to a single homogeneous composite yarn M. The fiber composition of yarn M was determined through calculation to be identical to the overall surface fiber composition of the surface yarns A, B, and C in Example 5, calculated using the actual weaving ratio (weft yarn A:B = 1:4, warp yarns all C, with the estimated mass ratio considering yarn count and density being approximately A:B:C = 10%:40%:50%). Specifically, it consists of 1.7% antibacterial submicron polyimide fiber, 65.5% antibacterial submicron meta-aramid, 26.1% antibacterial submicron para-aramid, 0.9% flame-retardant viscose, and 5.8% silver-plated nylon fiber. The entire surface structure uses yarn M, employing a 2-up, 2-down plain weave, resulting in a smooth and uniform surface without any textured or grid-like effects. All other process parameters are the same as in Example 5.

[0127] The test results of the product examples and comparative examples are shown in Table 1, where RPP represents the radiant heat protection value and TPP represents the thermal protection performance value. Gold, large, and white represent Staphylococcus aureus, Escherichia coli, and Candida albicans, respectively.

[0128] Table 1 Test results show that Examples 1-5, by optimizing the ratio of silver-plated nylon fiber, polyimide fiber, and aramid fiber in the surface yarn, and combining the uneven structure formed by the interweaving of various yarns with a specific pentagonal nested rhomboid air cavity design, achieved excellent comprehensive protective performance with a radiant heat protection value (RPP) of 8.6-10.3 cal / cm² and a thermal protection performance value (TPP) of 17.9-18.3 cal / cm², while maintaining good wearing comfort (total heat loss 500-620 W / m², water droplet diffusion time 12-15 s) and long-lasting antibacterial function (antibacterial rate after washing >87%). Specifically, the forest fire-fighting clothing fabrics of Examples 1-5 have good radiant heat resistance and comfort. The addition of silver-plated nylon fiber to the surface layer not only gives the fabric excellent antistatic properties, but also provides antibacterial properties and a certain degree of radiant heat reflection. In addition, the uneven texture formed by the interweaving of different yarn compositions and yarn counts further enhances the fabric's radiant heat reflection performance. The fabric uses ultra-elastic nickel-titanium alloy core-spun yarn as the connecting yarn between the outer and inner layers, forming a pentagonal nested with a horizontal rhombus and a vertical rhombus. When the fabric comes into contact with heat, the shape memory function of the alloy yarn allows it to quickly support the contraction of the inner and outer layers, forming irregular air cavities to increase thermal protection performance. At the same time, due to the density of the connecting yarn, the outer layer contracts even more densely, thus enhancing the reflection of radiant heat. When it moves away from the heat, the ultra-elastic nickel-titanium alloy core-spun yarn can quickly stretch, reducing the size of the air cavities formed between the outer and inner layers, and also reducing the density of the outer layer, allowing hot and humid gases inside and outside the fabric to be quickly expelled. In addition, the inner layer uses para-aramid and a combination of para-aramid and flame-retardant viscose, giving it a viscose-like yarn layer that is close to the skin, achieving rapid moisture absorption and thus providing excellent wearing comfort. Furthermore, the double-layer fabric woven in this design takes into account moisture resistance, thermal resistance, and thermal protection performance. After exposure to low radiant heat, the fabric surface color does not change, and the mechanical properties are not lost. It can be reused. After TPP testing, the fabric surface strength is reduced by 50%, but it still has certain thermal protection and mechanical properties. In addition, this product has good thermal and moisture comfort, providing forest firefighters with comfort and high radiant heat protection during forest fire fighting, making up for the shortcomings of existing forest fire fighting clothing fabrics in radiant heat protection performance, and highlighting excellent wearing comfort.

[0129] In Example 6, after removing the specific air cavity structure, the RPP and TPP decreased significantly, confirming the key role of the air cavity structure in improving thermal insulation performance. In Example 7, after removing the antibacterial particles, the thermal protection and comfort indicators were consistent with Example 5, but the antibacterial performance was lost. Comparative Example 1, due to the absence of silver-plated nylon fibers, showed a significant decrease in its RPP value, highlighting the necessity of this component for reflecting radiant heat. Comparative Example 2, using a pure aramid inner layer, experienced a sharp deterioration in comfort (total heat loss decreased to 415 W / m², water droplet diffusion time > 240 s), demonstrating the importance of introducing flame-retardant adhesive into the inner layer for maintaining wearing comfort. Comparative Example 3, while maintaining the overall material composition and air cavity structure, only changed the surface layer to a homogeneous flat structure, and its RPP value was significantly lower than that of Example 5, directly demonstrating the important contribution of the surface layer yarns of different fiber compositions and yarn counts interwoven to form a concave-convex structure in claim 1 to achieving high radiant heat protection performance.

[0130] Principles and steps not explicitly described in this invention are all obtainable by those skilled in the art through conventional technical means, and therefore will not be elaborated upon. Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A radiant heat protective forest firefighting suit fabric, characterized in that, The fabric includes an outer layer, an inner layer, and a bonding yarn for connecting the outer layer and the inner layer; The surface layer is woven from various surface yarns with different fiber compositions and yarn counts to form a textured structure. The surface yarns include silver-plated nylon fibers; the surface yarns also include at least two of polyimide fibers, meta-aramid fibers, and para-aramid fibers. The inner layer is woven from inner layer yarns, at least one of the inner layer yarns comprising para-aramid and flame-retardant viscose.

2. The fabric according to claim 1, characterized in that, The outer layer is woven from yarns A, B, and C; yarn A comprises 15%-25% polyimide fiber, 60%-70% meta-aramid fiber, 0%-15% flame-retardant viscose, and 2%-6% silver-plated nylon fiber; yarn C comprises 30%-42% para-aramid fiber, 52%-65% meta-aramid fiber, and 3%-6% silver-plated nylon fiber. And / or, The inner layer is woven from yarns B, D, and E; yarn D is a wrapped yarn, which is composed of 100% para-aramid staple fiber yarn and 100% flame-retardant viscose staple fiber yarn, and the flame-retardant viscose staple fiber yarn is located on the outer layer of yarn D; yarn E is para-aramid filament. The B yarn comprises 10%-22% para-aramid fiber, 75%-85% meta-aramid fiber, and 3%-8% silver-plated nylon fiber.

3. The fabric according to claim 2, wherein, The outer layer yarn includes outer layer warp yarn and outer layer weft yarn; the inner layer yarn includes inner layer warp yarn and inner layer weft yarn; The surface layer is woven with a 2-up, 1-down twill weave, and the warp and weft directions form a grid of 0.25-0.4cm. The surface layer yarn uses C yarn as the surface layer warp yarn and A yarn and B yarn as the surface layer weft yarn. The surface layer weft yarn is arranged in a 1:4 ratio of A yarn to B yarn, and the grid yarn is A yarn. The inner layer is woven in a 1-up, 1-down pattern, with D and E yarns as the inner layer warp yarns. The inner layer warp yarns are arranged in the following order: 2 D yarns, 1 E yarn, 1 D yarn, 1 E yarn, 2 D yarns, and 2 E yarns. The inner layer weft yarns are B yarns, D yarns, and E yarns, with the following order: 2 D yarns, 1 E yarn, 1 D yarn, 1 B yarn, 1 E yarn, 2 D yarns, 1 B yarn, 2 E yarns, 1 D yarn, 1 E yarn, and 1 B yarn.

4. The fabric according to claim 2, wherein, Yarn count of A is 48. s / 2-55 s / 2, the yarn count of B yarn is 42s, and the yarn count of C yarn is 40s. s / 2-45 s / 2; The yarn count of D yarn is 48. s / 2-50 s / 2; D yarn is made of 100% flame-retardant viscose 48s-50s yarn and 100% para-aramid staple fiber yarn 48s-50s wrapped together, with a wrapping twist of 750-850 twists / meter; E yarn is 200D with Z twist, and a twist of 220-250 twists / meter.

5. The fabric according to claim 2, wherein, The outer layer yarn includes outer layer warp yarn and outer layer weft yarn; the inner layer yarn includes inner layer warp yarn and inner layer weft yarn; the ratio of the outer layer warp yarn to the inner layer warp yarn is 1.58-1.65:1, and the ratio of the outer layer weft yarn to the inner layer weft yarn is 1.70-1.80:

1.

6. The fabric according to claim 2, wherein, The polyimide fibers, meta-aramid fibers, and para-aramid fibers are loaded with submicron-sized antibacterial particles.

7. The fabric according to claim 1, wherein, The bonding yarn is a core-spun yarn, composed of a core yarn and an outer layer of fibers. The core yarn is a super-elastic nickel-titanium alloy wire, and the outer layer of fibers includes aramid 1313 and flame-retardant viscose.

8. The fabric according to claim 7, wherein, The outer layer and the inner layer are connected by the connecting yarn to form a pentagonal nested with two rhombuses in a topological structure; the pentagonal structure generates an expansion air cavity when heated, and the rhombus structure forms a support and traction point inside the air cavity to prevent the fabric from collapsing when heated.

9. The fabric according to claim 8, wherein, The outer layer and the inner layer are interwoven and joined at multiple joint points by the connecting yarn, thereby forming the topological structure; the outer layer yarn includes outer layer warp yarn, and the inner layer yarn includes inner layer warp yarn; the joint point is the position where the connecting yarn intersects and is fixed with the outer layer warp yarn and the inner layer warp yarn; The joints are arranged according to a predetermined spatial distribution pattern to form a joint loop; a complete joint loop includes joints formed by seven weft-direction joining yarns, wherein: The first bonding yarn forms four first bonding points with the outer warp yarn and the inner warp yarn. The distances between adjacent first bonding points are 0.8-0.9cm, 0.4-0.5cm, and 0.8-0.9cm respectively. The distance between the last first bonding point in this bonding cycle and the first first bonding point in the adjacent cycle along the warp direction is 0.4-0.5cm. The second bonding yarn forms four second bonding points with the outer warp yarn and the inner warp yarn. The distances between adjacent second bonding points are 1.2-1.3cm, 0.2-0.3cm, and 1.2-1.3cm respectively. The distance between the last second bonding point in this bonding cycle and the first second bonding point in the adjacent cycle along the warp direction is 0.2-0.3cm. The third knot yarn forms three third knot points with the outer warp yarn and the inner warp yarn. The distance between adjacent third knot points is 1.5-1.6cm, and the distance between the last third knot point in this knot cycle and the first third knot point in the adjacent cycle along the warp direction is 1.5-1.6cm. The fourth knot yarn forms two fourth knot points with the outer warp yarn and the inner warp yarn. The distance between adjacent fourth knot points is 1.5-1.6cm, and the distance between the last fourth knot point in this knot cycle and the first fourth knot point in the adjacent cycle along the warp direction is 1.5-1.6cm. The fifth knot yarn forms three fifth knot points with the outer warp yarn and the inner warp yarn, and the arrangement of the fifth knot points is the same as that of the third knot points; The sixth knot yarn forms four sixth knot points with the outer warp yarn and the inner warp yarn, and the arrangement of the sixth knot points is the same as that of the second knot points; The seventh knot yarn forms four seventh knot points with the outer warp yarn and the inner warp yarn, and the arrangement of the seventh knot points is the same as that of the first knot points.

10. A method for preparing a radiant heat protective forest fire-fighting suit fabric as described in any one of claims 1-9, wherein the outer layer yarn comprises an outer layer warp yarn and an outer layer weft yarn; the inner layer yarn comprises an inner layer warp yarn and an inner layer weft yarn, the method comprising the following steps: Yarn preparation steps include: Prepare the outer layer yarn, the inner layer yarn, and the knotting yarn; The pre-weaving preparation steps include: calculating the total number of warp threads for the surface warp and the inner warp according to the arrangement ratio based on the weight and yarn count of the fabric; warping the surface warp and the inner warp separately to form a surface warp beam and an inner warp beam; integrating the surface warp beam and the inner warp beam into a surface warp beam and an inner warp beam respectively using a sizing machine; sizing the surface warp; and according to the designed fabric structure diagram and the warp and weft density configuration and cycle of the surface and inner layers, threading the surface warp and the inner warp into different heddle frames using a forward threading method, and then threading the threaded yarns onto the reed to complete the pre-weaving preparation. The weaving process includes: installing the warp beam prepared in the pre-weaving preparation step onto the loom, using a rapier double warp beam loom, setting the back beam to the middle back beam position, and adjusting the height of the lower back beam to 1000-1080 mm; installing the surface warp beam as the upper warp beam and the inner warp beam as the lower warp beam; setting the tension of the upper warp beam to 600-750 MV and the tension of the lower warp beam to 100-150 MV, and weaving in a cycle according to the designed weft yarn arrangement; The finishing steps include: using desizing enzyme to desize the greige fabric obtained from the weaving process to remove the sizing material applied to the warp yarns during weaving; washing away stains and desizing enzyme from the fabric surface; performing a durable waterproofing treatment on the fabric; and stretching the fabric to a specified width and stabilizing its dimensions under appropriate temperature and tension to obtain the finished fabric.

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