Multi-layer flame-retardant fabric with low-temperature cryogenic protection and flashover prevention functions and preparation method of multi-layer flame-retardant fabric

Abstract

The invention discloses a multi-layer flame-retardant fabric with low-temperature cryogenic protection and flashover prevention functions and a preparation method of the multi-layer flame-retardant fabric. The multi-layer flame-retardant fabric comprises a thermal protection outer layer, a heat buffer layer, a flame-retardant thermal insulation layer and a skin-friendly comfortable layer; the thermal protection outer layer is a three-dimensional warp-knitted spacer fabric subjected to hydrophobic treatment and comprises a thermal protection outer layer surface layer and a thermal protection outer layer inner layer, and spacer yarns are alternately connected back and forth between the thermal protection outer layer surface layer and the thermal protection outer layer inner layer in the single vertical direction to form the three-dimensional warp-knitted spacer fabric; the spacing distance between every two adjacent spacer yarns is 0 to 10 mm; the heat buffer layer is a coating formed on the inner layer of the thermal protection outer layer; the flame-retardant thermal insulation layer is a thermal insulation felt made of a flame-retardant material The skin-friendly comfortable layer is formed by flame-retardant cotton fabric, polyimide fabric or aramid fiber / flame-retardant viscose blended fabric. The combined fabric provided by the invention has the advantages of low-temperature cryogenic protection, flame retardance, high-heat protection performance and high-temperature resistance, and realizes the balance of structure, function and performance.

Description

Technical Field

[0001] The invention discloses a low-temperature and deep-cold protection and anti-explosion multi-layer flame-retardant fabric and a preparation method thereof, belonging to the field of professional protective equipment for low-temperature and deep-cold hazardous environments and explosion accident disposal. Background Art

[0002] When working in ultra-low temperature environments, such as aviation fuel filling, liquefied natural gas (LNG) plants, and fire emergency response, workers need to wear special protective clothing to protect themselves from extreme low temperatures and splashes of cryogenic media. However, in these scenarios, there is not only a threat of low temperatures, but also the cryogenic media leaks and vaporizes, which can easily explode when encountering fire, and the temperature is extremely high, reaching over 1000°C, causing burns and scalds to personnel. Therefore, it is particularly important to develop protective clothing made of composite fabrics that can adapt to ultra-low temperature environments and have anti-bombing combustion, high temperature resistance, and heat insulation properties.

[0003] Traditional low-temperature protective clothing mainly focuses on the functions of keeping warm and preventing low-temperature liquids from splashing. It often uses polyester fabric or polyester coated waterproof fabric as the outer layer, polyester flakes as the thermal insulation layer, cotton, polyester, nylon and other fabrics as the inner layer, and several layers are composited to form a fabric with low-temperature protection effect. However, the combination of these materials performs poorly in terms of anti-explosion and heat insulation, which results in the inability to effectively protect workers from heat damage and burns when a fire or deflagration occurs. For example, Chinese patent application CN206612235 U discloses an ultra-low temperature protective clothing, the fabric of which adopts a three-layer composite structure, the outer surface adopts acid and alkali resistant coated cloth, the middle insulation layer adopts two layers of snow cotton, and the inner layer adopts knitted flannel. Although it has excellent cold-proof and warm-keeping properties, it does not have flame retardant and heat-insulating properties, and cannot cope with the high temperature and flame hazards during accidental explosion and combustion of low-temperature deep-cold media. For example, Chinese patent application CN 205197060 U discloses an ultra-low temperature protective clothing, whose fabric adopts a three-layer structure. The outer layer is polyimide fiber with a waterproof layer on the outer surface. The middle layer is made of polyimide flakes, and the inner layer is polyimide fiber, polyester, nylon or cotton. Although this combined fabric has the properties of preventing splashes of low-temperature liquids and explosions, the polyimide material can only withstand a maximum temperature of 400°C. At high temperatures of 1000°C and above, it will melt, decompose and break, and lose its protective effect. Its temperature resistance limit still needs to be improved. Summary of the invention

[0004] The purpose of the present invention is to provide a multi-layer flame-retardant fabric with low-temperature and deep-cold protection and anti-explosion flame retardancy. Through innovative structural design and combination optimization, the new functional flame-retardant fabric can maximize the technical characteristics and advantages of each functional layer; under the basic requirements of ensuring excellent flame retardant performance and thermal protection comfort, the protective temperature range of the thermal protection fabric is broadened, and its high temperature protection can reach 1000°C, while the low temperature protection can be as low as -200°C, achieving comprehensive protection in extreme temperature environments.

[0005] The multi-layer flame retardant fabric with low-temperature deep-cold protection and anti-explosion flame retardancy provided by the present invention comprises a heat protection outer layer, a heat buffer layer, a flame retardant heat insulation layer and a skin-friendly comfort layer. Through the layered structural design, the heat transfer inward is reduced step by step to achieve deep-cold protection and anti-explosion flame retardancy heat insulation effects.

[0006] Among them, the thermal protection outer layer: the first line of protection against flames and thermal environments, uses organic / inorganic coupling to improve the material's adaptable temperature range; uses a three-dimensional warp-knitted spacer fabric structure to improve its thermal insulation ability; the fabric is hydrophobic to reduce the adhesion of low-temperature and deep-cold media; and achieves flame retardancy, high temperature resistance, heat insulation, flame penetration resistance, and protection against splashing of low-temperature media.

[0007] Among them, the heat buffer layer: a coating material located on the inner side of the thermal protection outer layer, using one or more fillers in radiant heat reflective materials, aerogel materials or phase change materials, dispersed in a suitable adhesive, and fixed on the inner side of the thermal protection outer layer by coating, thereby improving the thermal protection outer layer's ability to reflect, block or absorb radiant heat, reducing the conduction of radiant heat, and improving the overall thermal protection effect.

[0008] Among them, the flame retardant thermal insulation layer is a key layer to reduce heat transfer, which is made of materials with certain thermal insulation properties. The material itself has flame retardancy, thermal stability, low thermal conductivity, porosity, and looseness, which can block heat transfer and have a thermal insulation and heat preservation effect.

[0009] Among them, the skin-friendly and comfortable layer: directly contacts the human skin, giving the inner layer permanent flame retardant properties, comfortable touch, etc., using flame retardant cotton, polyimide or aramid / flame retardant viscose blended fabrics.

[0010] Specifically, the heat protection outer layer is a three-dimensional warp knitted spacer fabric with hydrophobic treatment, including a heat protection outer layer surface layer and a heat protection outer layer inner layer, and the spacer yarn is alternately connected back and forth in a single vertical direction between the heat protection outer layer surface layer and the heat protection outer layer inner layer to form the three-dimensional warp knitted spacer fabric; the connection mode of the spacer yarn with the heat protection outer layer surface layer and the heat protection outer layer inner layer is cross-type; the spacing distance between the spacer yarns is 0mm to 10mm;

[0011] The weight of the outer thermal protection layer is not less than 300 g / m2 ;

[0012] The heat buffer layer is a coating formed on the inner layer of the heat protection outer layer;

[0013] The flame retardant heat insulation layer is a heat insulation felt made of flame retardant material, which can not only block the external heat from transferring inwards, isolate the heat generated by the fire, but also block the body heat from transferring outwards, thus achieving a warming effect;

[0014] The skin-friendly and comfortable layer is formed of flame-retardant cotton fabric, polyimide fabric or aramid / flame-retardant viscose blended fabric.

[0015] Preferably, the heat-protective outer surface layer and the spacer yarn are both made of high-temperature resistant core-spun yarn;

[0016] The heat protection outer surface layer is made of the high temperature resistant core-spun yarn in a manner of interweaving warp yarn and weft yarn, and the fabric structure is plain weave, twill weave or satin weave.

[0017] Preferably, the high temperature resistant core-spun yarn consists of a core yarn and a covering yarn;

[0018] The core yarn accounts for 40% to 60% of the mass of the high temperature resistant core-spun yarn, and the covering yarn accounts for 60% to 40% of the mass of the high temperature resistant core-spun yarn.

[0019] The core yarn is made of inorganic material, which is one or more of basalt fiber filaments, quartz fiber filaments, glass fiber filaments, alumina fiber filaments, zirconia fiber filaments, silicon carbide fiber filaments and other inorganic fiber filaments;

[0020] The covered yarn is made of organic material and is made by blending the following fibers in mass fractions: 10% to 60% flame-retardant viscose fiber, 0% to 30% nylon fiber, and 10% to 50% aramid fiber or polyimide fiber.

[0021] Preferably, the heat protection outer layer and inner layer are made of flame retardant blended yarn, and the fabric structure is plain, twill or satin;

[0022] The flame-retardant blended yarn is made of the following fibers in percentage by mass: 40% to 60% of preoxidized silk fibers and 60% to 40% of para-aramid fibers.

[0023] The thermal protection outer layer fully combines the respective advantages of the two through organic / inorganic coupling, improves the overall high temperature resistance, improves the wearing performance and comfort performance of the high temperature resistant fiber, and reduces costs; the thermal protection outer layer adopts a three-dimensional warp knitted spacer fabric structure, and the spacer yarn supports the two surface fabric layers to form a spacer layer of a certain thickness. A large amount of still air is stored in the spacer layer, and still air is the medium with the smallest thermal conductivity in nature, so that the thermal protection outer layer has better thermal insulation performance than ordinary single-layer fabrics.

[0024] Preferably, the coating liquid used for the heat buffer layer is one or more of heat-insulating fillers, nano-scale potassium hexatitanate whiskers or titanium dioxide anti-radiation heat fillers or phase-change microcapsule materials, which are mixed with other auxiliary materials such as coupling agents and added to waterborne polyurethane to form;

[0025] The coating weight is not less than 100g / m 2 .

[0026] Preferably, the flame retardant heat insulation layer is made of a mixture of one or more of basalt, pre-oxidized yarn, polyimide, aromatic sulfone fiber, and aramid fiber;

[0027] The flame retardant heat insulation layer is a single layer or multi-layer structure, and the gram weight is 10-600g / m 2 ;

[0028] The skin-friendly and comfortable layer is made of flame-retardant cotton fabric, polyimide fabric or aramid / flame-retardant viscose blended fabric, and the fabric weight is 100-150g / m 2 , with permanent flame retardant properties, good moisture absorption, softness, and skin-friendly comfort;

[0029] The flame retardant heat insulation layer and the skin-friendly comfort layer are connected by a quilting process;

[0030] The heat protection outer layer with the heat buffer layer is superimposed on the flame retardant heat insulation layer to form an air layer between the flame retardant heat insulation layer. The overall fabric has excellent low-temperature and deep-cold protection, anti-explosion, flame retardancy and heat insulation properties.

[0031] The present invention also provides a method for preparing the multi-layer flame retardant fabric, comprising the following steps:

[0032] S1. Preparing high temperature resistant core-spun yarn and flame retardant blended yarn;

[0033] S2, preparing the heat protection outer layer: drawing a machine drawing, inputting the machine drawing into the control system of the full-automatic rapier loom, and then weaving the high temperature resistant core-spun yarn and the flame retardant blended yarn after drawing in the healds and reeds to obtain the heat protection outer layer fabric with a three-dimensional spacer structure;

[0034] S3, performing a hydrophobic treatment on the outer layer of the thermal protection outer layer;

[0035] S4, preparing a coating liquid for the heat buffer layer;

[0036] S5, applying the coating liquid on the inner side of the fabric of the heat protection outer layer and curing;

[0037] S6, connecting the flame retardant heat insulation layer and the skin-friendly comfort layer by a quilting process;

[0038] S7, stacking the heat protection outer layer coated with the heat buffer layer and the flame retardant heat insulation layer / the skin-friendly comfort layer connected by quilting to form an air layer to obtain the multi-layer flame retardant fabric.

[0039] In step S2, the hydrophobic treatment is performed by padding;

[0040] The hydrophobic agents used include, but are not limited to, fluorocarbons, silicones, polyurethanes, and acrylics.

[0041] The high temperature protection of the multi-layer flame retardant fabric of the present invention can reach 1000°C, while the low temperature protection can be as low as -200°C, thus achieving comprehensive protection in extreme temperature environments.

[0042] Compared with the existing inventions, the present invention has the following beneficial technical effects:

[0043] 1. The heat protection outer layer improves the high temperature resistance limit of the outer layer fabric through organic / inorganic coupling, and improves the wearing performance and comfort performance of the high temperature resistant inorganic fiber, reduces costs, and makes the high temperature resistance limit reach 1000℃, which improves the high temperature resistance effect; at the same time, the three-dimensional warp knitted spacer structure is adopted to make the heat protection outer layer have more static air layers, which improves the thermal insulation effect of the protective clothing.

[0044] 2. Each layer of material uses inherently flame-retardant materials, giving the whole a permanent flame-retardant property.

[0045] 3. Through the multi-layer matching scheme, the high temperature resistance and heat insulation performance of the thermal protection outer layer, the heat buffering performance of the heat buffer layer, and the heat insulation and warmth retention performance of the flame retardant insulation layer are combined, which improves the thermal protection function of the combined fabric and has excellent heat insulation effect. The clothing made of this fabric has anti-flammability function.

[0046] The composite fabric of the present invention has low-temperature and deep-cold protection as well as flame retardancy, high heat protection performance and high temperature resistance, thus achieving a balance in structure, function and performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 The cross-sectional structure diagram of the composite fabric of the present invention includes: (1) a heat protection outer layer; (2) a heat buffer layer; (3) a flame retardant heat insulation layer; and (4) a skin-friendly comfort layer.

[0048] Figure 2 The cross-sectional structure diagram of the heat-protective outer layer fabric in the combined fabric of the present invention; in the figure: (5) heat-protective outer layer surface layer; (6) spacer yarn; (7) heat-protective outer layer inner layer.

[0049] Figure 3 This is a design effect diagram of the heat-protective outer layer fabric in the combined fabric of the present invention (weft view); in the figure: (8) heat-protective outer layer surface layer; (9) spacer yarn; (10) heat-protective outer layer inner layer. DETAILED DESCRIPTION

[0050] The present invention will be further described below in conjunction with specific embodiments, but the present invention is not limited to the following embodiments.

[0051] Unless otherwise specified, the experimental methods used in the following examples are conventional methods.

[0052] Unless otherwise specified, the reagents, materials, instruments, etc. used in the following examples can be obtained from commercial sources.

[0053] The test method of the fabric properties of the present invention is as follows:

[0054] GB / T 5445-2014 “Test for vertical damage length, smoldering and afterflaming time of textile combustion performance”;

[0055] GB / T 38302-2019 Test method for thermal protection performance of protective clothing;

[0056] GB / T 3923.1-2013 “Tensile properties of textile fabrics-Part 1: Determination of breaking strength and elongation at break (strip method)”;

[0057] GB / T 3917.3-2009 “Tear properties of textile fabrics - Part 3: Determination of tear strength of trapezoidal specimens”;

[0058] GB / T 21196.2-2007 "Textiles - Determination of the abrasion resistance of fabrics by the Martindale method - Part 2: Determination of specimen damage";

[0059] GB / T 4745-2012 “Testing and evaluating the waterproof performance of textiles - Water-impregnation method”;

[0060] GB / T 4669-2008 “Textiles - Determination of mass per unit length and mass per unit area”.

[0061] Example 1. Preparation of composite fabric

[0062] This embodiment provides a multi-layer flame-retardant fabric for low-temperature and deep-cold protection and anti-explosion combustion, which comprises, from the outside to the inside, a heat protection outer layer, a heat buffer layer, a flame-retardant heat-insulating layer, and a skin-friendly comfort layer;

[0063] Among them, the heat buffer layer is combined with the heat protection outer layer by coating; the flame retardant heat insulation layer and the skin-friendly comfort layer are connected by quilting technology, and the heat protection outer layer with the heat buffer layer coating is superimposed on the outermost layer to form an air layer between the flame retardant heat insulation layer to obtain a combined fabric, such as Figure 1 shown.

[0064] The specific preparation steps are as follows:

[0065] 1. Preparation of high temperature resistant core-spun yarn and flame retardant blended yarn for the thermal protection outer layer: The thermal protection outer layer is woven with high temperature resistant core-spun yarn and flame retardant blended yarn; specifically, the flame retardant blended yarn is made of pre-oxidized silk fiber (accounting for 60%) and para-aramid fiber (accounting for 40%); high temperature resistant core-spun yarn, wherein the high temperature resistant core yarn is basalt continuous fiber filament with a diameter of 9μm, and the covering yarn is made of flame retardant viscose fiber (accounting for 30%), nitrile chlorofiber fiber (accounting for 20%), and meta-aramid fiber (accounting for 50%), the core yarn accounts for 40% of the core-spun yarn, and the covering yarn accounts for 60% of the core-spun yarn.

[0066] 2. In this embodiment, the flame-retardant blended yarn is 20S / 2; the high temperature resistant core-spun yarn is 24S single yarn, the single yarn twist coefficient is 480T / m, and the yarn unevenness is 10.5%.

[0067] 3. Preparation of the thermal protection outer layer: Specifically, the surface of the thermal protection outer layer is made of basalt core-spun yarn, the organizational structure is a plain weave structure, the warp density is 330 strands / 10cm, the weft density is 240 strands / 10cm, and the single-layer weight is 240g / m 2 The middle spacer yarn uses basalt core-spun yarn as the vertical yarn, the spacing height of the spacer yarn is 8mm, and the span of the warp spacer yarn is 5 weft yarns; the outer and inner layers of the heat protection layer use flame-retardant blended yarn, the organization structure is plain weave, the warp density is 330 strands / 10cm, the weft density is 240 strands / 10cm, and the single layer weight is 220g / m 2 ; The weight of the thermal protection outer fabric is 480g / m 2 ; Breaking strength is 2350N / 5cm in warp direction and 1830N / 5cm in weft direction; Trapezoidal tear is 132N in warp direction and 110N in weft direction; Flame retardant performance is 0s afterburning in warp and weft direction of the surface layer, 0mm in damage length, no melting or dripping, 0s afterburning in warp and weft direction of the inner layer, 2mm in damage length; Wear resistance is 15,000 times. The cross-sectional structure diagram of the thermal protection outer layer is as follows Figure 2 and Figure 3 .

[0068] 4. Hydrophobic treatment of the outer layer of thermal protection: Specifically, first clean the outer layer of thermal protection fabric to remove surface grease, dust and other impurities to ensure that the fabric surface is clean and smooth; mix the C5 finishing agent with water in proportion (5%), add auxiliaries, stir evenly to form a finishing liquid; treat the fabric with two dips and two rolls of finishing liquid, and control the roll-off rate at 70% to 80%; dry the treated fabric at 105°C, and then bake at 170°C for 1 minute to complete the hydrophobic finishing. After treatment, the water-repellent level of the fabric reaches 4-5, with excellent waterproof performance.

[0069] 5. Preparation of thermal buffer layer: The thermal buffer layer is applied to the thermal protective outer fabric by coating; specifically, the thermal buffer layer uses silica aerogel powder and rutile nano-titanium dioxide as fillers, which are added to deionized water together with aluminum hydroxide powder, stirred into a suspension with an electric stirrer, and then added with dispersant sodium dodecylbenzene sulfonate after sufficient stirring, and then stirred and dispersed, and then added with water-based polyurethane and stirred evenly to obtain a coating liquid; the ratio of silica aerogel powder, rutile nano-titanium dioxide, and aluminum hydroxide powder is 1:1:3; the mass fraction of silica aerogel is 10%, and the mass fraction of nano-titanium dioxide is 10%; the thermal protective outer fabric is fixed on the needle plate of the coating machine for coating, the coating machine speed is controlled at 10mm / s, the coating thickness is 0.20mm, and the coating is applied 2 to 4 times, and then the fabric is placed in an oven at 80 to 100°C and dried for 30 minutes to obtain a coated fabric. The coating weight is 110g / m 2 .

[0070] 6. The flame retardant insulation layer is pre-oxidized silk felt with a gram weight of 200g / m 2 .

[0071] 7. The skin-friendly and comfortable layer is made of aramid / flame-retardant viscose blended fabric with a gram weight of 125g / m 2 .

[0072] 8. Preparation of combined fabrics: The flame retardant insulation layer and the skin-friendly comfort layer are sewn and connected by a quilting process, and a superimposed unit is used between the heat protection outer layer / heat buffer layer and the flame retardant insulation layer / quilting / skin-friendly comfort layer to form a certain air layer in the middle of the combined fabric.

[0073] The test results of the combined fabric obtained in Example 1 of the present invention are as follows:

[0074] The overall weight of the combined fabric is 920g / m 2 , flame and radiation heat protection performance (TPP) is 65cal / cm 2; Observe the combined fabric, the surface of the thermal protection outer layer does not shrink. Due to the presence of high temperature resistant basalt core-spun yarn, the surface of the thermal protection outer layer maintains a certain skeleton strength, and the inner layer of the thermal protection outer layer is carbonized; under the 1000℃ spray gun flame, the inner surface temperature rises by 24℃, and the burning time is 33s.

[0075] Comparative Example 1

[0076] The difference from Example 1 is that the heat protection outer layer does not use spacer fabric. Specifically, a single layer of fabric that is basically the same as the surface layer and the inner layer of the heat protection outer layer is used, and the two layers are superimposed. The rest is the same as Example 1.

[0077] The test results of the combined fabrics obtained in Comparative Example 1 are as follows:

[0078] The overall weight of the combined fabric is 900g / m 2 , flame and radiation heat protection performance (TPP) is 51cal / cm 2 ; Observe the combined fabric, its thermal protection outer layer does not shrink, and due to the presence of high temperature resistant basalt core-spun yarn, a certain skeleton strength is maintained, and the center of the inner layer of the thermal protection outer layer is damaged; under the 1000℃ spray gun flame, the inner surface temperature rises by 24℃, and the burning time is 25s. The results show that if the three-dimensional spacer fabric is not used as the thermal protection outer layer, the overall thermal protection performance of the fabric will be significantly reduced. This shows that the presence of the spacer structure can improve the thermal protection performance of the combined fabric.

[0079] Comparative Example 2

[0080] The difference from Example 1 is that the core yarn of the high temperature resistant core-spun yarn is made of different material. Specifically, the core yarn of the core-spun yarn is made of para-aramid filaments, and the linear density of the para-aramid filaments is 120D; the covering yarn of the core-spun yarn is the same as that in Example 1, and is made of flame-retardant viscose fiber (30%), nitrile chloroform fiber (20%), and meta-aramid fiber (50%). The core yarn accounts for 40% of the core yarn, and the covering yarn accounts for 60% of the core yarn.

[0081] The flame retardant performance of the outer surface of the thermal protection layer is 0s afterburning in the warp and weft directions, with a damage length of 5mm, no melting or dripping, and the inner layer has 0s afterburning in the warp and weft directions, with a damage length of 2mm.

[0082] The test results of the combined fabrics obtained in Comparative Example 2 are as follows:

[0083] The overall weight of the combined fabric is 910g / m 2 , flame and radiation heat protection performance (TPP) is 48cal / cm 2, observing the combined fabric, the surface of the thermal protection outer layer was damaged, the inner layer of the thermal protection outer layer was carbonized, the spacer yarn was carbonized and broken, causing the collapse of the spacer structure; under the 1000℃ spray gun flame, the inner surface temperature rose by 24℃, and the burning time was 24s.

[0084] The results show that if inorganic high temperature resistant core-spun yarn is not used as the outermost layer and spacing yarn of the heat protection outer layer, the protective ability of the fabric against high temperature flames will be significantly reduced, damage will occur, the spacing structure will be maintained for a shorter time, and heat will be more easily transferred to the inside. This shows that the present invention improves the high temperature resistance limit of the fabric by selecting inorganic high temperature resistant core-spun yarn, which has a significant impact on the overall performance.

[0085] Comparative Example 3

[0086] The difference between Example 1 and Embodiment 1 is that the covering yarn of the high temperature resistant core-spun yarn is made of different materials. Specifically, the covering yarn is made of flame-retardant viscose fiber (30%), nylon fiber (20%), and flame-retardant cotton fiber (50%). The core yarn accounts for 40% of the core-spun yarn, and the covering yarn accounts for 60% of the core-spun yarn.

[0087] The flame retardant performance of the outer surface of the thermal protection layer is that the warp and weft directions continue to burn for 0s, the damage length is 2mm, there is no melting or dripping, and the inner layer continues to burn for 2s in the warp and weft directions, and the damage length is 3mm.

[0088] The test results of the combined fabrics obtained in Comparative Example 3 are as follows:

[0089] The overall weight of the combined fabric is 910g / m 2 , flame and radiation heat protection performance (TPP) is 56cal / cm 2 ; , observe the combined fabric, the surface of the thermal protection outer layer does not shrink, maintains a certain skeleton strength, and the inner layer of the thermal protection outer layer is carbonized; under the 1000℃ spray gun flame, the inner surface temperature rises by 24℃, and the burning time is 28s.

[0090] The results show that by changing the covering yarn material of the core-spun yarn and using flame-retardant cotton to replace the aramid fiber with better heat resistance and flame retardant properties, the flame retardant properties of the outer surface fabric of the thermal protection layer decreased, and the overall thermal protection performance decreased. This shows that in the selection of the material of the covering yarn, the temperature resistance and flame retardant properties of the fiber should be improved as much as possible, which will help improve the overall performance.

[0091] Comparative Example 4

[0092] The difference between Example 1 and Embodiment 1 is that the composition ratio of the covering yarn of the high temperature resistant core-spun yarn is different. Specifically, the covering yarn is made of flame-retardant viscose fiber (30%), nylon fiber (30%), and meta-aramid fiber (40%). The core yarn accounts for 40% of the core yarn, and the covering yarn accounts for 60% of the core yarn.

[0093] The test results of the combined fabrics obtained in Comparative Example 4 are as follows:

[0094] The overall weight of the combined fabric is 915g / m 2 , flame and radiation heat protection performance (TPP) is 63cal / cm 2 ; , observe the combined fabric, the surface of the thermal protection outer layer does not shrink, maintains a certain skeleton strength, and the inner layer of the thermal protection outer layer is carbonized; under the 1000℃ spray gun flame, the inner surface temperature rises by 24℃, and the burning time is 32s.

[0095] The results show that changing the composition ratio of the covering yarn of the core-spun yarn has little effect on the overall thermal protection performance.

[0096] Comparative Example 5

[0097] The difference from Example 1 is that the composition ratio of the flame retardant blended yarn is different. Specifically, the flame retardant blended yarn is made of pre-oxidized silk fiber (accounting for 40%) and para-aramid fiber (accounting for 60%). The flame retardant performance of the heat-protective outer layer and inner layer fabric made of the flame retardant blended yarn is 0s in the warp and weft directions, and the damaged length is 6mm, which is slightly longer.

[0098] The test results of the combined fabric obtained in Comparative Example 5 are as follows:

[0099] The overall weight of the combined fabric is 925g / m 2 , flame and radiation heat protection performance (TPP) is 62cal / cm 2 ; Observe the combined fabric, the surface of the thermal protection outer layer does not shrink, maintaining a certain skeleton strength, the inner layer of the thermal protection outer layer is carbonized, and has a slight shrinkage compared with Example 1. This is because the thermal stability of the pre-oxidized silk fiber is stronger. By appropriately increasing the ratio, the thermal shrinkage rate of the fabric is reduced; under the 1000°C spray gun flame, the inner surface temperature rises by 24°C, and the burning time is 31s.

[0100] The results show that changing the composition ratio of flame retardant blended yarn has little effect on the overall thermal protection performance.

[0101] In general, the combined fabric provided by the present invention has excellent flame retardancy, heat insulation, warmth retention, high and low temperature resistance, and anti-explosion properties. Among them, the application of high temperature resistant core-spun yarn, especially inorganic high temperature resistant core yarn, and the existence of the spacing structure have a significant effect on the thermal protection performance.

[0102] The above-described embodiments are only preferred embodiments for fully illustrating the present invention, and the protection scope of the present invention is not limited thereto. Equivalent substitutions or changes made by those skilled in the art based on the present invention are within the protection scope of the present invention. The protection scope of the present invention shall be subject to the claims.

Claims

1. A multi-layer flame-retardant fabric with low-temperature and deep-cold protection and anti-explosion flame retardancy, comprising a heat protection outer layer, a heat buffer layer, a flame-retardant and heat-insulating layer and a skin-friendly and comfortable layer; The heat protection outer layer is a three-dimensional warp knitted spacer fabric with hydrophobic treatment, including a heat protection outer layer surface layer and a heat protection outer layer inner layer, and the spacer yarn is alternately connected back and forth in a single vertical direction between the heat protection outer layer surface layer and the heat protection outer layer inner layer to form the three-dimensional warp knitted spacer fabric; the connection between the spacer yarn and the heat protection outer layer surface layer and the heat protection outer layer inner layer is a cross type; the spacing distance between the spacer yarns is 0mm to 10mm; The heat buffer layer is a coating formed on the inner layer of the heat protection outer layer; The flame retardant heat insulation layer is a heat insulation felt made of flame retardant material; The skin-friendly and comfortable layer is formed of flame-retardant cotton fabric, polyimide fabric or aramid / flame-retardant viscose blended fabric.

2. The multi-layer flame retardant fabric according to claim 1, characterized in that: The heat protection outer surface layer and the spacer yarn are both made of high temperature resistant core-spun yarn; The heat protection outer surface layer is made of the high temperature resistant core-spun yarn in a manner of interweaving warp yarn and weft yarn, and the fabric structure is plain weave, twill weave or satin weave.

3. The multi-layer flame retardant fabric according to claim 2, characterized in that: The high temperature resistant core-spun yarn is composed of a core yarn and a covering yarn; The core yarn accounts for 40% to 60% of the mass of the high temperature resistant core-spun yarn, and the covering yarn accounts for 60% to 40% of the mass of the high temperature resistant core-spun yarn. The core yarn is made of inorganic material, which is one or more of basalt fiber filaments, quartz fiber filaments, glass fiber filaments, alumina fiber filaments, zirconia fiber filaments, silicon carbide fiber filaments and other inorganic fiber filaments; The covered yarn is made of organic material and is made by blending the following fibers by mass fraction: 10% to 60% of flame-retardant viscose fiber, 0% to 30% of nylon fiber, and 10% to 40% of aramid fiber or polyimide fiber.

4. The multi-layer flame retardant fabric according to any one of claims 1 to 3, characterized in that: The inner and outer layers of the heat protection layer are made of flame-retardant blended yarn, and the fabric structure is plain, twill or satin; The flame-retardant blended yarn is made of the following fibers in percentage by mass: 40% to 60% of preoxidized silk fibers and 60% to 40% of para-aramid fibers.

5. The multi-layer flame retardant fabric according to any one of claims 1 to 4, characterized in that: The coating liquid used in the heat buffer layer is one or more of heat-insulating fillers, nano-scale potassium hexatitanate whiskers or titanium dioxide anti-radiation heat fillers or phase-change microcapsule materials, mixed with other auxiliary materials such as coupling agents and added to water-based polyurethane to form; The coating weight is not less than 100g / m 2 .

6. The multi-layer flame retardant fabric according to any one of claims 1 to 5, characterized in that: The material of the flame retardant heat insulation layer is a mixture of one or more of basalt, pre-oxidized silk, polyimide, aromatic sulfone fiber, and aramid fiber; The flame retardant heat insulation layer is a single layer or multi-layer structure, and the gram weight is 10-600g / m 2 ; The skin-friendly and comfortable layer is made of flame-retardant cotton fabric, polyimide fabric or aramid / flame-retardant viscose blended fabric, and the fabric weight is 100-150g / m 2 .

7. The multi-layer flame retardant fabric according to any one of claims 1 to 6, characterized in that: The flame retardant heat insulation layer and the skin-friendly comfort layer are connected by a quilting process; The heat protection outer layer with the heat buffer layer is stacked on the flame retardant heat insulation layer to form an air layer between the flame retardant heat insulation layer.

8. The method for preparing the multi-layer flame retardant fabric according to any one of claims 1 to 7, comprising the following steps: S1. Preparing high temperature resistant core-spun yarn and flame retardant blended yarn; S2, preparing the heat protection outer layer: drawing a machine drawing, inputting the machine drawing into the control system of the full-automatic rapier loom, and then weaving the high temperature resistant core-spun yarn and the flame retardant blended yarn after drawing in the healds and reeds to obtain the heat protection outer layer fabric with a three-dimensional spacer structure; S3, performing a hydrophobic treatment on the outer layer of the thermal protection outer layer; S4, preparing a coating liquid for the heat buffer layer; S5, applying the coating liquid on the inner side of the fabric of the heat protection outer layer and curing; S6, connecting the flame retardant heat insulation layer and the skin-friendly comfort layer by a quilting process; S7, stacking the heat protection outer layer coated with the heat buffer layer and the flame retardant heat insulation layer / the skin-friendly comfort layer connected by quilting to form an air layer to obtain the multi-layer flame retardant fabric.

9. The preparation method according to claim 8, characterized in that: In step S2, the hydrophobic treatment is performed by padding; The hydrophobic agents used include, but are not limited to, fluorocarbons, silicones, polyurethanes, and acrylics.

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