A nonwoven fiber web composite inorganic board and its preparation method

Abstract

An inorganic board made of nonwoven fiber web composite and its preparation method are disclosed. The inorganic board made of nonwoven fiber web composite comprises two layers of nonwoven fiber web composite and an inorganic slurry. The inorganic slurry fills the gaps between the fiber webs of the upper and lower layers of nonwoven fiber web composite and is cured to form the inorganic board made of nonwoven fiber web composite. The inorganic board made of nonwoven fiber web composite has the characteristics of high strength and high nail-holding power.

Description

Technical Field

[0001] This article relates to the field of construction, and in particular to nonwoven fiber composite mesh, inorganic boards composed of nonwoven fiber mesh, and their preparation methods. Background Technology

[0002] Gypsum board is widely used as a green and environmentally friendly product for interior wall construction. However, existing gypsum boards have a fragile gypsum core with a paper surface, resulting in poor impact resistance and nail-holding power. This makes it inconvenient to hang heavy objects on the surface, insufficient strength for interior partition walls, and requires vertical handling during transport to prevent breakage. Because fibers are difficult to disperse and flow in gypsum slurry, methods such as adding inorganic fibers to the slurry have very limited effects and cannot fundamentally solve the problems of toughness and strength in gypsum board. Similarly, while embedding glass mesh into the core of the gypsum board or bonding glass cloth to the surface can improve its strength to some extent, the performance improvement is still very limited because it only involves bonding layered glass fibers to gypsum.

[0003] Nonwoven fabrics are textiles formed without spinning or weaving. They are porous honeycomb fiber webs / fabrics made by arranging short fibers or filaments in a directional or random manner and bonding them together. Common preparation methods include needle punching, thermal bonding, and chemical bonding. In recent years, the production technology of nonwoven materials has developed rapidly, enabling the production of three-dimensional honeycomb structures. These structures are widely used in medical and health applications, carpets, cleaning materials, geotechnical engineering, sound absorption and insulation, and filtration. From the nanoscale fiber diameters required for mask filter cloths and battery separators to the 10-micron to millimeter-scale fiber diameters for industrial scouring pads, seedbeds, sewage filters, and industrial carpets, three-dimensional honeycomb webs can be mass-produced. Summary of the Invention

[0004] The following is an overview of the subject matter described in detail herein. This overview is not intended to limit the scope of the claims.

[0005] Plant fibers are biodegradable and excellent green and environmentally friendly reinforcing materials. For example, hemp fibers have the best strength among natural fibers, are widely available, and have low cost. They also have outstanding advantages such as being renewable and biodegradable, making them an excellent choice for preparing biodegradable composite reinforcing materials. By selecting biodegradable natural plant fibers such as hemp fiber, coconut shell fiber, and straw fiber, and using nonwoven methods to create a three-dimensional honeycomb network, and then combining it with gypsum to form a composite material, the aforementioned shortcomings of existing gypsum boards can be effectively overcome.

[0006] This application describes a nonwoven fiber web with honeycomb-like pores, made by hot melt adhesive for the main fiber / binder or by combining the main fiber with welded fibers. This web is then bonded to a surface layer with hot melt adhesive to form a nonwoven fiber composite web. The upper and lower nonwoven fiber webs are then injected with gypsum slurry, resulting in a gypsum-filled composite web that is bonded together to form a single inorganic board. This board exhibits high strength and high nail-holding power.

[0007] The first aspect of this application provides a nonwoven fiber composite web having honeycomb-like pores, comprising a fiber web and a surface layer bonded to the fiber web.

[0008] In one exemplary embodiment, the fiber web has honeycomb-like pores.

[0009] In one exemplary embodiment, the thickness of the surface layer is 30-1500 μm, for example, 30 μm, 100 μm, 300 μm, 600 μm, 800 μm, 1000 μm, 1200 μm, 1400 μm or 1500 μm, but is not limited to the listed values, and other unlisted values ​​within this range are also applicable.

[0010] In one exemplary embodiment, the surface layer may be selected from at least one of inorganic fibers, organic fibers, organic / inorganic fiber blended fabrics, nonwoven porous fabrics, and paper made from plant fibers. The surface layer exhibits good compatibility with the fiber web to facilitate bonding the two layers together, imparts excellent sound insulation and thermal insulation properties to the gypsum board, and its porosity and hydrophilicity give the gypsum board surface excellent adhesion and coating properties.

[0011] In one exemplary embodiment, the nonwoven porous fabric is selected from at least one of chemically bonded nonwoven fabrics, thermally bonded nonwoven fabrics, needle-punched nonwoven fabrics, spunlace nonwoven fabrics, meltblown nonwoven fabrics, and spunbond nonwoven fabrics.

[0012] In one exemplary embodiment, the surface layer may be a nonwoven fabric composed of glass fiber and other fibers, wherein the other fibers are selected from at least one of straw fiber, hemp fiber, viscose fiber, polylactic acid fiber, PET fiber and polyamide fiber;

[0013] Preferably, the thickness of the nonwoven fabric is 500-1500μm, for example, 500μm, 1000μm or 1500μm, but it is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0014] In one exemplary embodiment, the surface layer may also be a protective paper used for conventional gypsum board.

[0015] In one exemplary embodiment, the fiber web is a three-dimensional mesh structure formed by bonding randomly oriented main fibers with a spray adhesive, or a three-dimensional mesh structure formed by bonding a mixture of main fibers and fused fibers.

[0016] In one exemplary embodiment, the thickness of the fiber web is 4-10 mm.

[0017] In one exemplary embodiment, the fiber web has three-dimensional, irregular, and interconnected pores;

[0018] Preferably, the average fiber spacing of the fiber web is 1 mm to 10 mm.

[0019] In one exemplary embodiment, the main fiber is selected from one or more of plant fibers, inorganic fibers, and petrochemical fibers;

[0020] Optionally, the petrochemical fiber is selected from one or more of polyamide, polyurethane, and polyacetate;

[0021] Optionally, the inorganic fiber is selected from at least one of basalt fiber and glass fiber;

[0022] Optionally, the plant fiber is a biodegradable natural plant fiber, preferably selected from at least one of coconut shell fiber, coconut palm fiber, hemp fiber, wood fiber, bamboo fiber, wheat straw fiber, rice straw fiber, and straw fiber;

[0023] Optionally, the hemp fiber is selected from at least one of flax, kenaf, jute, and apocynum;

[0024] Preferably, the diameter of the main fiber is 30μm to 200μm, for example, 30-60μm, 40-90μm, 40-140μm, etc., but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0025] Preferably, the fiber length of the main fiber is 3mm to 15mm.

[0026] In one exemplary embodiment, the host fiber is formed by mixing two or more fibers to create a honeycomb structure with the desired porosity range and high resilience.

[0027] In one exemplary embodiment, the spray adhesive is a hot melt adhesive, optionally selected from at least one of polyether-modified polyester, EVA hot melt adhesive, TPU hot melt adhesive, PES hot melt adhesive, maleic anhydride-grafted polyethylene hot melt adhesive, PA hot melt adhesive, PO hot melt adhesive, polycaprolactone hot melt adhesive, and polyhydroxybutyrate / valerate hot melt adhesive.

[0028] In one exemplary embodiment, the welded fiber is selected from at least one of modified polyethylene terephthalate (PET) copolymer fiber, maleic anhydride grafted polypropylene, phthalic anhydride grafted polyethylene, benzoic anhydride grafted ES fiber, polyurethane fiber, polyurethane elastomer fiber, modified polyurethane fiber, and modified polyamide fiber.

[0029] Optionally, the diameter of the fusion-bonded fiber is 10 μm to 50 μm.

[0030] The second aspect of this application provides a method for preparing a nonwoven fiber composite web, comprising: forming the fiber web and bonding and curing the fiber web with a surface layer.

[0031] In one exemplary embodiment, in the fiber web forming step, the main fibers of the fiber web are bonded and fixed together by a molten spray adhesive, including: loosening the main fibers, uniformly applying the hot melt adhesive of the spray adhesive to the surface of the main fibers, and blowing and forming the web; specifically, including:

[0032] After the main fiber is fully opened into individual fibers and separated, it enters the nozzle or gap. At the same time, the nozzle outlet is provided with a spraying hole. The hot melt adhesive of the sprayed binder is sprayed out from the spraying hole and evenly coated on the surface of the main fiber. The main fiber, which is evenly coated with the sprayed binder, is blown to the web forming machine through the auxiliary air duct outside the outlet to form a web.

[0033] Preferably, in the method, the minimum amount of adhesive sprayed from the spray nozzle has an average areal density of 1 g / m³. 2 -50.0g / m 2 For example, 5g / m 2 10g / m 2 20g / m 2 30g / m 2 40g / m 2 Or 50g / m 2 This applies to, but is not limited to, the listed values; other unlisted values ​​within this range also apply.

[0034] In one exemplary embodiment, the bonding temperature of the spray adhesive is 110-160°C, for example, 110°C, 120°C, 130°C, 140°C, 150°C or 160°C, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0035] In one exemplary embodiment, in the fiber web forming step, the main fibers of the fiber web are bonded and fixed together by fusion splicing fibers, including: loosening the main fibers and fusion splicing fibers separately, mixing and loosening them, and then blowing them into a web; specifically, it includes:

[0036] After the main fiber and the welded fiber are fully opened into individual fibers and separated, they are mixed and opened. The mixed and opened main fiber and the welded fiber are sent into a nozzle or gap and blown into a web forming machine under high pressure hot air. The web forming machine can be matched with negative pressure air to assist in web forming.

[0037] In one exemplary embodiment, the melting point of the fused fiber is 115°C-180°C, for example, 115°C, 120°C, 130°C, 140°C, 150°C, 160°C, 170°C or 180°C, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0038] In an exemplary embodiment, the bonding and curing of the fiber web and the surface layer includes: dipping one side of the fiber web into hot melt adhesive in a hot melt adhesive tank, bonding it to the surface layer, and then curing it to form a nonwoven fiber composite web.

[0039] Preferably, the hot melt adhesive is selected from at least one of polyether-modified polyester, EVA hot melt adhesive, TPU hot melt adhesive, PES hot melt adhesive, maleic anhydride-grafted polyethylene hot melt adhesive, PA hot melt adhesive, PO hot melt adhesive, polycaprolactone hot melt adhesive, and polyhydroxybutyrate / valerate hot melt adhesive.

[0040] A third aspect of this application provides an inorganic board material composed of nonwoven fiber webs, comprising two nonwoven fiber webs and an inorganic slurry, wherein the fiber webs of the two nonwoven fiber webs are arranged facing each other and the inorganic slurry fills the pores of the fiber webs of the upper and lower layers of the nonwoven fiber webs and is cured to form an inorganic board material composed of nonwoven fiber webs.

[0041] In one exemplary embodiment, the inorganic slurry is a fluid, pumpable slurry made by mixing hemihydrate gypsum and silicate cement as the main raw materials in water.

[0042] In one exemplary embodiment, the raw materials of the inorganic slurry, by weight, include: 65-90 parts hemihydrate gypsum, 3-13 parts silicate cement, 1-6 parts waste paper pulp, 1-6 parts filler, 0.2-3 parts industrial starch, and 0.5-4 parts additives.

[0043] Preferably, the hemihydrate gypsum is in the following weight parts, for example, 65, 70, 75, 80, 85 or 90, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0044] Preferably, the silicate cement has a weight ratio of, for example, 3, 6, 9, 12 or 13, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0045] Preferably, the waste paper pulp is in parts by weight, for example, 1, 2, 3, 4, 5 or 6, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0046] Preferably, the filler weight parts are, for example, 1, 2, 3, 4, 5 or 6, but not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0047] Preferably, the industrial starch is in parts by weight, for example, 0.2, 0.5, 1.0, 1.5, 2.0, 2.5 or 3.0, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0048] Preferably, the additive is present in parts by weight, for example, 0.5, 1, 2, 3 or 4, but is not limited to the listed values; other unlisted values ​​within this range are also applicable.

[0049] In one exemplary embodiment, the filler comprises one or more of lime and fly ash.

[0050] In one exemplary embodiment, the additive includes at least one of a water-reducing agent, a coagulation regulator, and a foaming agent.

[0051] In one exemplary embodiment, the water-reducing agent is selected from one or more of aliphatic water-reducing agents and polycarboxylate water-reducing agents; preferably, it is selected from one or more of potassium tartrate, acrylic acid and sodium acrylate, sulfonated styrene, isothiocyanate, and naphthalene ethanesulfonic acid.

[0052] In one exemplary embodiment, the coagulation regulator is selected from one or more of gypsum dihydrate, calcium chloride, calcium carbonate, volcanic ash, and sulfate; for example, the sulfate is calcium sulfate dihydrate.

[0053] In one exemplary embodiment, the foaming agent is selected from one or more of sodium dodecyl sulfate, sodium fatty alcohol polyoxyethylene ether sulfate, sodium α-alkenyl sulfonate, and hydrogen peroxide.

[0054] The fourth aspect of this application provides a method for preparing an inorganic board composed of nonwoven fiber web, including grouting of a lower layer of nonwoven fiber web, grouting of an upper layer of nonwoven fiber web, composite shaping of the two grouted nonwoven fiber webs, solidification drying, and cutting and packaging.

[0055] In one exemplary embodiment, the grouting of the lower nonwoven fiber composite mesh includes:

[0056] The lower nonwoven fiber composite mesh is introduced into the lower grouting section with its surface layer facing down. Inorganic slurry is injected into the fiber web side of the lower nonwoven fiber composite mesh until it fills the interconnected pores of the lower nonwoven fiber composite mesh and abuts against the surface layer of the lower nonwoven fiber composite mesh, forming an integral structure in which the lower nonwoven fiber composite mesh is embedded in the continuous phase of inorganic slurry.

[0057] Optionally, in the lower grouting section, a first slurry pipe and a first upper pressure roller are sequentially provided on one side of the fiber web of the lower nonwoven fiber composite web along the conveying direction. A first vibration device is provided at the bottom of the surface layer of the lower nonwoven fiber composite web. After the inorganic slurry is injected through the first slurry pipe, it is squeezed by the first upper pressure roller and vibrated by the first vibration device and injected to fill the interconnected honeycomb pores of the lower nonwoven fiber composite web and abut against the surface layer.

[0058] Optionally, the vibration frequency of the first vibration device is 30 to 200 Hz, for example, 30, 60, 90, 120, 150, 180 or 200, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0059] Optionally, the first vibration device may be a first vibration belt, and the first vibration belt is provided with a transmission roller to drive the first vibration belt to vibrate.

[0060] In one exemplary embodiment, the grouting of the upper nonwoven fiber composite mesh includes:

[0061] The upper nonwoven fiber composite web is introduced into the upper grouting section with its surface layer facing downwards. Inorganic slurry is injected into the fiber web side of the upper nonwoven fiber composite web, filling the interconnected pores of the upper nonwoven fiber composite web and abutting against the surface layer of the upper nonwoven fiber composite web, forming an integral structure in which the upper nonwoven fiber composite web is embedded in the continuous phase of inorganic slurry. The upper grouting section is located above the lower grouting section, and the conveying direction of the upper nonwoven fiber composite web is parallel to and opposite to the conveying direction of the lower nonwoven fiber composite web, with the same conveying speed.

[0062] Optionally, in the upper grouting section, a second slurry pipe and a second upper pressure roller are sequentially provided on one side of the fiber web of the upper nonwoven fiber composite web along the conveying direction. A second vibration device is provided at the bottom of the surface layer of the upper nonwoven fiber composite web. The inorganic slurry is injected through the second slurry pipe, squeezed by the second upper pressure roller and vibrated by the second vibration device, and injected to fill the interconnected honeycomb pores of the upper nonwoven fiber composite web and abut against the surface layer.

[0063] Optionally, the vibration frequency of the second vibration device is 30 to 200 Hz, for example, 30, 60, 90, 120, 150, 180 or 200, but is not limited to the listed values. Other unlisted values ​​within this range are also applicable.

[0064] Optionally, the second vibration device may be a second vibration belt, which has a transmission roller inside to drive the second vibration belt to vibrate.

[0065] In an exemplary embodiment, the composite shaping of the upper and lower nonwoven fiber composite webs after grouting includes: after grouting, turning the conveying direction of the upper nonwoven fiber composite web by 180° so that the fiber web of the upper nonwoven fiber composite web and the fiber web of the lower nonwoven fiber composite web face each other, and the conveying direction and speed are the same.

[0066] The upper nonwoven fiber composite web is brought into contact with and compacted after being turned, and excess slurry is removed and bonded together to form a continuous and integral structure of upper and lower slurry layers.

[0067] Optionally, during the turning process, a turning device is provided at the bottom of the surface layer of the upper nonwoven fiber composite web;

[0068] Optionally, the steering device is a steering roller;

[0069] Optionally, during the turning process, a baffle plate is also provided on one side of the upper nonwoven fiber composite web to fully prevent the slurry injected into the fiber web from flowing out and overflowing.

[0070] In one exemplary embodiment, the coagulation, drying, cutting, and packaging includes: coagulating, drying, cutting, and packaging the composite and shaped material to obtain an inorganic board material composited with a nonwoven fiber web.

[0071] The fifth aspect of this application provides an inorganic board material composed of a nonwoven fiber web prepared by the above method.

[0072] Compared with the prior art, this application has the following technical effects:

[0073] This application provides an inorganic board material comprising a nonwoven honeycomb fiber composite mesh, which is composed of an inorganic slurry filled with nonwoven honeycomb fibers having interconnected honeycomb pores. This solves the problem that the overall strength of gypsum board cannot be effectively improved by adding short-cut fibers to conventional gypsum slurry.

[0074] 1) A nonwoven fiber composite web is provided, comprising a honeycomb fiber web and a surface layer bonded to one side thereof. The honeycomb fiber web is formed by spraying an adhesive onto randomly oriented main fibers or by mixing and bonding main fibers with welded fibers, and has a three-dimensional mesh structure and three-dimensional random and interconnected pores;

[0075] 2) The highly fluid inorganic slurry is poured into the pores of the honeycomb fiber network to form an integral continuous phase, which fully maintains the strength of the inorganic board after the inorganic slurry is cured;

[0076] 3) The outer side of the board is a non-woven honeycomb fiber composite mesh surface layer, which can be inorganic fiber, organic fiber and organic / inorganic fiber blended fabric, non-woven porous fabric, and can be directly obtained as a decorative board with a three-dimensional velvet effect after surface spraying and dyeing treatment, while having better sound insulation and heat insulation performance.

[0077] 4) The fibers are interconnected to form a three-dimensional network, which fully integrates with the inorganic continuous phase, fundamentally improving the comprehensive mechanical properties of the board, such as flexural strength, impact resistance, and tensile strength, and increasing nail holding power by more than 150%.

[0078] Other features and advantages of this application will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the application. Other advantages of this application can be realized and obtained by means of the solutions described in the description and the accompanying drawings. Attached Figure Description

[0079] The accompanying drawings are used to provide an understanding of the technical solutions of this application and constitute a part of the specification. They are used together with the embodiments of this application to explain the technical solutions of this application and do not constitute a limitation on the technical solutions of this application.

[0080] Figure 1 This is a schematic diagram of the structure of the inorganic board material composited with nonwoven fiber web according to this application;

[0081] Figure 2 for Figure 1 A magnified view of a portion of the image;

[0082] Figure 3 This is a schematic diagram of the structure of the inorganic board material composited with nonwoven fiber web according to this application;

[0083] Figure 4 for Figure 3 A magnified view of a portion of the image;

[0084] Figure 5 This is a schematic diagram of the production process of the inorganic board composite with nonwoven fiber web in this application;

[0085] Figure 6This is a schematic diagram of another possible production process for the inorganic board composited with nonwoven fiber web in this application.

[0086] Explanation of reference numerals in the attached figures:

[0087] 1: Surface layer; 2: Fiber web; 3: First slurry pipe; 4: First upper pressure roller; 5: First vibration device; 6: Second slurry pipe; 7: Second vibration device; 8: Turning roller; 9: First transmission device; 10: Second transmission device; 11: Baffle plate; 12: Inorganic slurry. Detailed Implementation

[0088] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in detail below. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be arbitrarily combined with each other.

[0089] The present invention will be further described in detail below with reference to specific examples, but these examples should not be construed as limiting the present invention.

[0090] The raw materials used in the comparative examples and embodiments of this application are all commercially available products.

[0091] The inorganic slurry formulations in Examples 1 to 5 are shown in Table 1. The components and weight ratios of the additives in Examples 1-5 are as follows:

[0092] Potassium tartrate: sulfonated styrene: isothiocyanate: gypsum dihydrate: calcium carbonate: volcanic ash: sodium sulfate of fatty alcohol polyoxyethylene ether = 10:5:3:17:30:25:10.

[0093] Example 1.

[0094] In this nonwoven fiber composite web, the main fibers are jute fibers with a diameter of 25μm to 80μm and a length of 3-10mm. The welded fibers are maleic anhydride-grafted polypropylene fibers with a diameter of 15μm to 40μm and a length of 4-15mm. The main fibers and welded fibers are separated into individual fibers after thorough opening, then mixed and opened again. The mixture is then fed into an air-jet gap and blown by hot air at 135-145℃ onto a web-forming machine. The main fibers are bonded together by overlapping welded fibers, producing a nonwoven fiber composite web with interconnected pores. The specific thickness of the fiber web is 9mm. The surface layer is made of jute needle-punched fabric with a needle density of 400 needles / cm². 2 Surface layer density 100g / m³ 2 The surface layer is 0.6-0.9mm thick and is bonded to the honeycomb fiber mesh with maleic anhydride-grafted polyethylene hot melt adhesive.

[0095] See Figure 1-2The nonwoven fiber composite web includes a fiber web 2 and a surface layer 1 bonded to the fiber web 2, wherein the fiber web 2 has honeycomb-like pores.

[0096] See Figure 3-4 The inorganic board made of nonwoven fiber web composite includes two nonwoven fiber composite webs and an inorganic slurry. The fiber webs 2 of the two nonwoven fiber composite webs are arranged facing each other, and the inorganic slurry fills the pores of the fiber webs 2 of the upper and lower layers of nonwoven fiber composite webs and is cured to form an inorganic board made of nonwoven fiber web composite.

[0097] A method for preparing nonwoven fiber web composite inorganic boards includes the following steps:

[0098] Grouting of the lower nonwoven fiber composite mesh: The lower nonwoven fiber composite mesh is introduced into the lower grouting section with its surface layer facing downwards. Inorganic slurry is injected into the fiber web side of the lower nonwoven fiber composite mesh, filling the interconnected pores and abutting against the surface layer of the lower nonwoven fiber composite mesh, forming an integral structure in which the lower nonwoven fiber composite mesh is embedded in the continuous phase of inorganic slurry; see also Figure 5 In the lower grouting section, a first slurry pipe 3 and a first upper pressure roller 4 are sequentially arranged on one side of the fiber web of the lower nonwoven fiber composite web along the conveying direction. A first vibration device 5 is arranged at the bottom of the surface layer of the lower nonwoven fiber composite web. After the inorganic slurry is injected through the first slurry pipe 3, it is squeezed by the first upper pressure roller 4 and vibrated by the first vibration device 5 to fill the interconnected honeycomb pores of the lower nonwoven fiber composite web and abut against the surface layer. Here, the first vibration device 5 is a first vibration belt, and a transmission roller is provided inside the first vibration device 5.

[0099] Grouting of the upper nonwoven fiber composite mesh: The upper nonwoven fiber composite mesh is introduced into the upper grouting section with its surface layer facing downwards. Inorganic slurry is injected into the fiber web side of the upper nonwoven fiber composite mesh, filling the interconnected pores and abutting against the surface layer of the upper nonwoven fiber composite mesh, forming an integrated structure in which the upper nonwoven fiber composite mesh is embedded in the continuous phase of inorganic slurry; see also Figure 5The upper grouting section is located above the lower grouting section. The conveying direction of the upper nonwoven fiber composite web is parallel and opposite to that of the lower nonwoven fiber composite web, and the conveying speed is the same. In the upper grouting section, a second slurry pipe 6 and a second upper pressure roller (not shown) are provided on one side of the fiber web of the upper nonwoven fiber composite web along the conveying direction. A second vibration device 7 is provided at the bottom of the surface layer of the upper nonwoven fiber composite web. The inorganic slurry is injected through the second slurry pipe 6, vibrated by the second vibration device 7, and fills the interconnected honeycomb pores of the upper nonwoven fiber composite web and abuts against the surface layer. The second vibration device 7 is a second vibration belt, and a transmission roller is provided inside the second vibration device.

[0100] The bonding and shaping of the upper and lower layers of grouted nonwoven fiber composite mesh includes: after grooving, turning the conveying direction of the upper nonwoven fiber composite mesh 180° so that the fiber web of the upper nonwoven fiber composite mesh faces the fiber web of the lower nonwoven fiber composite mesh, and the conveying direction and speed are the same; bringing the upper and lower nonwoven fiber composite mesh into contact and compacting them, so that the interior and middle parts of the upper and lower nonwoven fiber composite meshes are filled with grooving; then removing excess grooving and bonding them together to form a continuous integral structure of upper and lower grooving layers; see also Figure 5 During the turning process, a turning device, namely a turning roller 8, is provided at the bottom of the surface layer of the upper nonwoven fiber composite web; see also Figure 6 During the turning process, a baffle plate 11 is also provided on one side of the fiber web of the upper nonwoven fiber composite web;

[0101] The solidification, drying, cutting, and packaging process includes: solidifying, drying, cutting, and packaging the composite and shaped materials to obtain inorganic boards made of nonwoven fiber webs.

[0102] Example 2.

[0103] In the nonwoven fiber composite web, the main fiber of the fiber web is poplar fiber with a diameter of 10μm to 20μm and a length of 3-6mm. The spray adhesive is modified polyhydroxybutyrate / valerate hot melt adhesive, and the welding temperature is 130-140℃ to produce a honeycomb fiber web. The surface layer is made by hot melt bonding of modified poplar fiber and maleic anhydride grafted modified polystyrene short fiber to form a nonwoven fabric with a fiber diameter of 5μm to 30μm and a length of 3-15cm. The surface layer thickness is 0.5-1.0mm. The honeycomb fiber web and the surface layer are bonded and fixed with modified polyethylene terephthalate hot melt adhesive.

[0104] The rest is the same as in Example 1.

[0105] Example 3.

[0106] In the nonwoven fiber composite web, the main fibers are bamboo pulp fibers provided by Guangzhou Jinmu Paper Industry Co., Ltd., with a diameter of 12μm to 35μm and a length of 2-6mm. The welded fibers are benzoic anhydride-grafted ES fibers, with a diameter of 6μm to 18μm and a length of 3-15mm. The main fibers and welded fibers are fully opened into individual fibers, separated, mixed, and then opened and finished. They are then fed into an air-jet gap and blown by hot air at 125-135℃ onto a web-forming machine to form a web. The main fibers are bonded together by the welded fibers to produce a nonwoven honeycomb fiber composite web with three-dimensional random and interconnected pores. The surface layer is made of flame-retardant modified PET nonwoven fabric with a specification of 70g / m². 2 The surface layer thickness is 0.3-0.8mm.

[0107] The rest is the same as in Example 1.

[0108] Example 4.

[0109] In nonwoven fiber composite mesh, the main fiber of the fiber mesh is coconut shell fiber, which is generally 3-8cm in length and 0.05-0.3mm in diameter. The fusion bonding fiber is made of polybutylene terephthalate to form a honeycomb fiber mesh. The surface layer is a protective paper with a thickness of 0.5-0.8mm. The honeycomb fiber mesh is bonded to the protective paper with EVA hot melt adhesive.

[0110] The rest is the same as in Example 1.

[0111] Example 5.

[0112] In the nonwoven fiber composite web, the main fiber of the fiber web is flax fiber with a diameter of 10μm to 30μm and a length of 3-8mm. The adhesive used for spraying is polyether-modified PET hot melt adhesive, with a welding temperature of 140-155℃, to produce a honeycomb-shaped fiber web. The surface layer is a nonwoven fabric produced by melt spinning a blend of polyethylene succinate and polybutylene terephthalate, with a fiber diameter of 5μm to 20μm and a thickness of 0.3-0.7mm after hydroentangling. The honeycomb fiber web and the surface layer are bonded and fixed with modified polyester hot melt adhesive.

[0113] The rest is the same as in Example 1.

[0114] Table 1. Inorganic slurry proportioning table

[0115]

[0116]

[0117] Comparative Example 1.

[0118] Commercially available Taishan brand ordinary gypsum board, 12mm thick.

[0119] Comparative Example 2.

[0120] The gypsum board is filled with 1.5% wt glass fiber.

[0121] test:

[0122] The inorganic boards prepared in the examples and comparative examples were tested. All test samples were 12 mm thick. The results are shown in Table 2.

[0123] Table 2. Properties of Inorganic Boards Composite with Nonwoven Fiber Web

[0124]

[0125]

[0126] Experimental tests have shown that, compared with ordinary gypsum board, the nonwoven fiber composite mesh of this invention improves nail-holding force by more than 150% and flexural strength by more than 50% (see Table 2 for details). The flexural strength test adopted the American standard ASTM C473-17, and the nail-holding force test adopted the standard GBT / 14018-2009.

[0127] Conclusion: This application provides an inorganic board material comprising a nonwoven honeycomb fiber composite mesh, which is composed of inorganic slurry filled with nonwoven honeycomb fibers having interconnected honeycomb pores. This solves the problem that the overall strength of gypsum board obtained by adding chopped fibers to conventional gypsum slurry is difficult to effectively improve.

[0128] 1) A nonwoven fiber composite mesh is provided, consisting of a honeycomb fiber mesh and a surface layer bonded to one side thereof. The honeycomb fiber mesh is formed by randomly oriented main fibers through spray bonding agent or by a mixture of main fibers and fused fibers bonded together, possessing a three-dimensional mesh structure and three-dimensional random and interconnected pores; 2) A highly fluid inorganic slurry is injected to fill the pores within the honeycomb fiber mesh to form an integral continuous phase, fully maintaining the strength of the inorganic board after the inorganic slurry is cured; 3) The outer side of the board is a nonwoven honeycomb fiber composite mesh surface layer, which can be inorganic fiber, organic fiber, organic / inorganic fiber blended fabric, or nonwoven porous fabric. After surface spraying and dyeing treatment, a decorative board with a three-dimensional velvet effect can be directly obtained, while also having better sound insulation and heat insulation performance; 4) The fibers are interconnected to form a three-dimensional mesh, fully utilizing the integral structure with the inorganic continuous phase, fundamentally improving the comprehensive mechanical properties of the board, such as flexural strength, impact resistance, and tensile strength, and increasing nail holding power by more than 150%.

[0129] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A method for making a nonwoven fiber web composite inorganic panel, the nonwoven fiber web composite inorganic panel comprising two nonwoven fiber composite webs and an inorganic slurry, the nonwoven fiber composite web comprising a fiber web and a face layer bonded to the fiber web, wherein, The two nonwoven fiber composite webs are arranged facing each other, and the inorganic slurry fills the pores of the upper and lower layers of the nonwoven fiber composite webs and is cured to form an inorganic board material composed of nonwoven fiber webs. The preparation method includes: Grouting of the lower nonwoven fiber composite mesh: The lower nonwoven fiber composite mesh is introduced into the lower grouting section with its surface layer facing down. Inorganic slurry is injected into the fiber mesh side of the lower nonwoven fiber composite mesh until it fills the interconnected pores of the lower nonwoven fiber composite mesh and abuts against the surface layer of the lower nonwoven fiber composite mesh, forming an integral structure in which the lower nonwoven fiber composite mesh is embedded in the continuous phase of inorganic slurry. The upper nonwoven fiber composite mesh is injected with grout. The upper nonwoven fiber composite mesh is introduced into the upper grouting section with its surface layer facing down. Inorganic slurry is injected into the fiber web side of the upper nonwoven fiber composite mesh, filling the interconnected pores of the upper nonwoven fiber composite mesh and abutting against the surface layer of the upper nonwoven fiber composite mesh, forming an integral structure in which the upper nonwoven fiber composite mesh is embedded in the continuous phase of inorganic slurry. The upper grouting section is located above the lower grouting section, and the conveying direction of the upper nonwoven fiber composite mesh is parallel to and opposite to the conveying direction of the lower nonwoven fiber composite mesh, with the same conveying speed. The upper and lower layers of nonwoven fiber composite mesh are composite shaped by grouting. After grouting, the conveying direction of the upper nonwoven fiber composite mesh is turned 180° so that the fiber mesh of the upper nonwoven fiber composite mesh and the fiber mesh of the lower nonwoven fiber composite mesh face each other and the conveying direction and speed are the same. The upper nonwoven fiber composite mesh and the lower nonwoven fiber composite mesh are then brought into contact and compacted. Excess grout is removed and the mesh is bonded together to form a continuous structure of upper and lower grout layers. Solidification, drying, cutting, and packaging: The composite-shaped material is solidified, dried, cut, and packaged to obtain an inorganic board made of nonwoven fiber web composite. The outer side of the inorganic board composite with nonwoven fiber mesh is the surface layer of nonwoven fiber composite mesh.

2. The method for preparing the nonwoven fiber web composite inorganic board according to claim 1, wherein, The surface layer is selected from at least one of inorganic fibers, organic fibers, organic / inorganic fiber blended fabrics, nonwoven porous fabrics, and paper made from plant fibers; or the surface layer is a nonwoven fabric composed of glass fiber and other fibers, wherein the other fibers are selected from at least one of straw fiber, hemp fiber, viscose fiber, polylactic acid fiber, PET fiber, and polyamide fiber; or the surface layer is a protective paper for gypsum board. The fiber web is a three-dimensional mesh structure formed by bonding randomly oriented main fibers with a spray adhesive, or a three-dimensional mesh structure formed by bonding a mixture of main fibers and fusion-bonded fibers.

3. The method for preparing the nonwoven fiber web composite inorganic board according to claim 2, wherein, The main fiber is selected from one or more of plant fibers, inorganic fibers and petrochemical fibers; The fusion-bonded fiber is selected from at least one of the following: modified polyethylene terephthalate copolymer fiber, maleic anhydride-grafted polypropylene, phthalic anhydride-grafted polyethylene, benzoic anhydride-grafted ES fiber, polyurethane fiber, and modified polyamide fiber.

4. The method for preparing the nonwoven fiber web composite inorganic board according to claim 2, wherein, The thickness of the surface layer is 30-1500 μm; The thickness of the fiber web is 4-10 mm, and the average fiber spacing of the fiber web is 1 mm to 10 mm; The diameter of the main fiber is 30μm to 200μm, and the fiber length of the main fiber is 3mm to 15mm; The diameter of the fusion-bonded fiber is 10 μm to 50 μm.

5. The method for preparing the inorganic board composite of nonwoven fiber web according to any one of claims 1 to 4, wherein, The raw materials of the inorganic slurry, by weight, include: 65-90 parts hemihydrate gypsum, 3-13 parts silicate cement, 1-6 parts waste paper pulp, 1-6 parts filler, 0.2-3 parts industrial starch, and 0.5-4 parts additives.

6. The method for preparing the nonwoven fiber web composite inorganic board according to claim 5, wherein, The filler comprises one or more of lime and fly ash; The additives include at least one of water-reducing agents, coagulation regulators, and foaming agents; The water-reducing agent is selected from one or more of aliphatic water-reducing agents and polycarboxylate water-reducing agents; The coagulation regulator is selected from one or more of calcium chloride, calcium carbonate, volcanic ash, and sulfate; The foaming agent is selected from one or more of sodium dodecyl sulfate, sodium fatty alcohol polyoxyethylene ether sulfate, sodium α-alkenyl sulfonate, and hydrogen peroxide.

7. The method for preparing the inorganic board composite of nonwoven fiber web according to any one of claims 1 to 4, wherein, In the lower grouting section, a first slurry pipe and a first upper pressure roller are sequentially arranged along the conveying direction on one side of the fiber web of the lower nonwoven fiber composite web. A first vibration device is provided at the bottom of the surface layer of the lower nonwoven fiber composite web. After the inorganic slurry is injected through the first slurry pipe, it is squeezed by the first upper pressure roller and vibrated by the first vibration device to fill the interconnected honeycomb pores of the lower nonwoven fiber composite web and abut against the surface layer; and / or In the upper grouting section, a second slurry pipe and a second upper pressure roller are provided on one side of the fiber web of the upper nonwoven fiber composite web along the conveying direction. A second vibration device is provided at the bottom of the surface layer of the upper nonwoven fiber composite web. The inorganic slurry is injected through the second slurry pipe, squeezed by the second upper pressure roller and vibrated by the second vibration device, and fills the interconnected honeycomb pores of the upper nonwoven fiber composite web and abuts against the surface layer.

8. The method for preparing the nonwoven fiber web composite inorganic board according to claim 7, wherein, The first vibration device is a first vibration belt, and the second vibration device is a second vibration belt.

9. The method for preparing the nonwoven fiber web composite inorganic board according to claim 8, wherein, The vibration frequencies of the first vibration device and the second vibration device are 30 to 200 Hz; The first and second vibrating belts are each equipped with a drive roller.

10. A method for preparing an inorganic board composite of nonwoven fiber web according to any one of claims 1 to 4, wherein, During the turning process, a turning device is provided at the bottom of the surface layer of the upper nonwoven fiber composite web.

11. The method for preparing the nonwoven fiber web composite inorganic board according to claim 10, wherein, The steering device is a steering roller.

12. The method for preparing the inorganic board composite of nonwoven fiber web according to any one of claims 1 to 4, wherein, During the turning process, a baffle plate is also provided on one side of the fiber web of the upper nonwoven fiber composite web.

13. The method for preparing the inorganic board composite with nonwoven fiber web according to any one of claims 1 to 4, further comprising the step of preparing the nonwoven fiber composite web, including: Fiber web formation and bonding / curing of the fiber web with the surface layer: In the fiber web forming step, the main fibers of the fiber web are bonded and fixed together by molten spray adhesive, or the main fibers of the fiber web are bonded and fixed together by fusion splicing fiber overlap.

14. The method for preparing the nonwoven fiber web composite inorganic board according to claim 13, wherein, The bonding and curing of the fiber web and the surface layer includes: dipping one side of the fiber web into hot melt adhesive in a hot melt adhesive tank and bonding and curing it with the surface layer to form a nonwoven fiber composite web.

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