Carbon-sandwiched cloth manufacturing process

Abstract

The manufacturing process comprises the following steps: providing a first PET (Polyethylene Terephthalate) layer, a second PET layer and an active carbon resin layer between the first PET layer and the second PET layer; sequentially puncturing the three layers by adopting a special needle with barbs; the first silk thread is hooked out of the first PET layer through needle movement, and the second silk thread is hooked out of the second PET layer; the two silk threads are entangled in the activated carbon resin layer; and glue-free connection is formed through multi-point repetition. The process does not need an adhesive, is environment-friendly and efficient, is firm in fiber bridging, and is suitable for an air purification material.

Description

Technical Field

[0001] This invention relates to the technical field of carbon fiber reinforced cloth, and in particular to a process for manufacturing carbon fiber reinforced cloth. Background Technology

[0002] Carbon fiber reinforced fabric, as a highly efficient functional composite material, has been widely used in environmental protection fields such as air purification and water treatment. Its typical structure usually consists of two layers of polyethylene terephthalate (PET) spunbond nonwoven fabric as support layers, with a filter layer rich in activated carbon powder sandwiched in between. This structure aims to utilize the physical strength of PET material to provide skeletal support, while fully leveraging the large specific surface area and adsorption capacity of activated carbon to capture and remove pollutants such as odors and volatile organic compounds (VOCs) from gases.

[0003] Currently, the mainstream commercial manufacturing process in this field generally adopts adhesive bonding technology. Specifically, manufacturers usually add liquid adhesives (such as polyurethane adhesives, acrylic adhesives, etc.) to activated carbon powder, and distribute them evenly through methods such as impregnation, spraying, or scraping. Then, the upper and lower layers of PET material are pressed onto both sides of the activated carbon layer, and the three are combined into a whole by the curing effect of the adhesive.

[0004] However, this traditional adhesive bonding process has several inherent technical defects that urgently need to be addressed. First, from a production process perspective, the process is cumbersome and difficult to control in terms of quality. Parameters such as adhesive viscosity, solid content, coating uniformity, and curing temperature and time all need to be precisely controlled. Deviations in any step can lead to problems such as delamination, adhesive spots, and uneven hardness in the finished product, increasing production complexity and the defect rate. Second, from the perspective of product performance and environmental protection, its drawbacks are even more prominent. Most organic adhesives themselves leave residues and continuously release volatile organic compounds such as formaldehyde and benzene series compounds, which undoubtedly constitutes "secondary pollution," contradicting the original intention of carbon fiber cloth to purify the air and severely restricting its application in high-end, enclosed living environments (such as hospitals, laboratories, and infant rooms). In addition, adhesives can partially block the microporous structure of activated carbon, leading to a reduction in its specific surface area, adsorption capacity, and efficiency, affecting the final filtration efficiency of the product. Finally, from the perspective of product durability, adhesives may be at risk of aging, becoming brittle, or failing in humid and hot environments after long-term use, leading to interlayer separation and shortening the product's service life.

[0005] Therefore, there is an urgent need in this field to develop a new carbon cloth manufacturing process that does not require adhesives, is simple to implement, is environmentally friendly and efficient, and can maintain or even improve the filtration performance of activated carbon, in order to overcome the fundamental shortcomings of existing technologies. Summary of the Invention

[0006] This application provides a process for manufacturing carbon fiber reinforced cloth, including the following steps: A first PET layer, a second PET layer, and an activated carbon resin layer disposed between the two are provided; A special needle is used to sequentially puncture the first PET layer, the activated carbon resin layer, and the second PET layer; Through the movement of the special needle, some fibers are hooked out from the first PET layer to form a first filament, and some fibers are hooked out from the second PET layer to form a second filament; The first and second filaments are entangled or intertwined in the activated carbon resin layer. The above puncture and hooking operations are repeated at multiple points, so that the first PET layer and the second PET layer are connected without glue through the first filament and the second filament to form carbon fiber cloth.

[0007] As a preferred technical solution for the manufacturing process of carbon fiber reinforced cloth, the tip of the specially made needle is provided with barbs or hook-like structures for hooking fibers.

[0008] As a preferred technical solution for the manufacturing process of carbon-coated cloth, the activated carbon resin layer is a resin fiber felt mixed with activated carbon powder.

[0009] As a preferred technical solution for the manufacturing process of carbon fiber reinforced cloth, the first filament and the second filament are composed of their respective corresponding PET layer body fibers.

[0010] As a preferred technical solution for the manufacturing process of carbon fiber reinforced cloth, the puncture operation is repeated at multiple points to form a uniformly distributed array of needle puncture points.

[0011] Compared with existing adhesive bonding methods, this invention adopts a glue-free needle-punching and hooking process. Special needles directly hook out the fibers of the upper and lower PET layers, causing them to entangle within the activated carbon resin layer to form a strong fiber bridging network. This completely eliminates the use of adhesives, preventing the volatilization of harmful substances and achieving true environmental protection. Furthermore, it results in higher peel strength, lower activated carbon shedding rate, and significantly enhanced structural stability. Simultaneously, it eliminates complex processes such as gluing and drying, greatly improving production efficiency and significantly reducing costs. The filtration performance and air permeability are superior to or equivalent to traditional processes, making it particularly suitable for air purification applications with stringent requirements for environmental protection and durability. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the manufacturing process for preparing carbon fiber reinforced cloth according to this application; Attached diagram descriptions: 1. Special needle; 2. First layer of PET; 3. Activated carbon resin layer; 4. Second layer of PET; 5. First thread; 6. Second thread; Detailed Implementation

[0013] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the examples in the specification.

[0014] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0015] Secondly, the term "an embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places throughout this specification does not necessarily refer to the same embodiment, nor is it a single embodiment or an embodiment selectively excluded from other embodiments.

[0016] Example Example 1: Laboratory manual needle-punching preparation of small-sample carbon cloth clips Step 1: Provide a first PET layer, a second PET layer, and an activated carbon resin layer disposed between the two.

[0017] Take a weight of 60g / m 2 A 0.6mm thick polyethylene terephthalate (PET) needle-punched nonwoven fabric was used as the first and second PET layers, each measuring 15cm × 15cm. A resin fiber felt containing activated carbon powder (80 mesh, 65% by mass) was used as the activated carbon resin layer, with a thickness of 3.0mm and a size of 15cm × 15cm. The three layers of materials were stacked flat in the order of "first PET layer – activated carbon resin layer – second PET layer", and temporarily fixed around the edges with plastic clips to ensure no wrinkles or shifting.

[0018] Step 2: Use a special needle to puncture the first PET layer, the activated carbon resin layer and the second PET layer in sequence.

[0019] A hand-punched crochet hook is selected as a special hook. The hook is 60mm long and the tip is equipped with a barb on one side (barb depth 0.4mm). The operator inserts the hook vertically from the center point of the upper surface of the first PET layer and passes through the first PET layer (with slight resistance), the activated carbon resin layer (compressed by about 20%), and the second PET layer in sequence, until the tip of the hook passes through the lower surface of the second PET layer by 2mm, ensuring that all three layers are completely penetrated.

[0020] Step 3: By moving the special needle, some fibers are hooked out from the first PET layer to form a first thread, and some fibers are hooked out from the second PET layer to form a second thread.

[0021] After the needle tip pierces the lower surface, rotate the hook 90° clockwise so that the barb hooks onto the fibers inside the second PET layer; then slowly pull the hook back along the original needle hole path. The barb first pulls out the fibers of the second PET layer to form the second thread (average length 15mm). As it continues to move upward, the barb hooks onto the fibers of the first PET layer and pulls them out to form the first thread (average length 10mm). Both threads are composed of the fibers of their respective PET layers.

[0022] Step 4: Make the first filament and the second filament entangle or intertwine with each other in the activated carbon resin layer.

[0023] Continue pulling back the hook until the needle tip is completely removed from the upper surface of the first PET layer, and the barb releases the fibers; due to the elastic retraction of the fibers, the first and second filaments naturally cross and entangle inside the activated carbon resin layer, forming a fiber entanglement point with a diameter of about 1.2mm; gently press around the needle hole to make the three layers of materials fit tightly together.

[0024] Step 5: Repeat the above puncture and hooking operations at multiple points to connect the first PET layer and the second PET layer without adhesive through the first and second threads, forming a carbon fiber reinforced cloth.

[0025] Using a 5×5 grid (2cm spacing) as the target, repeat steps 2 to 4, with each point operation taking about 35 seconds; after completion, remove the clamp to obtain a 15cm×15cm sample with carbon cloth clamped, the needle-punched dots are evenly distributed, and there is no adhesive residue on the surface.

[0026] Example 2: Semi-automatic desktop single-needle head equipment for preparing sample rolls Step 1: Provide a first PET layer, a second PET layer, and an activated carbon resin layer disposed between the two.

[0027] Select 50g / m 2 PET nonwoven fabric rolls with a width of 30cm are used as the first and second PET layers; resin fiber felt rolls containing activated carbon powder (70% by mass) are used as the activated carbon resin layer, with a thickness of 2.5mm and a width of 30cm; the three rolls are fed synchronously through an infrared alignment system to ensure that the interlayer alignment deviation is ≤1mm.

[0028] Step 2: Use a special needle to puncture the first PET layer, the activated carbon resin layer and the second PET layer in sequence.

[0029] A desktop single-needle reciprocating needle punching machine is used, equipped with a machine hook needle (55mm long, with double barbs at the needle tip); the puncture depth is set to 48mm, the needle tip descends vertically, and passes through the first PET layer, the activated carbon resin layer, and the second PET layer in sequence, with the needle tip protruding 3mm from the lower surface.

[0030] Step 3: By moving the special needle, some fibers are hooked out from the first PET layer to form a first thread, and some fibers are hooked out from the second PET layer to form a second thread.

[0031] The needle stops at the bottom dead center for 0.3 seconds and rotates slightly by 15°, with the double barbs hooking the upper and lower layers of fibers respectively; during the needle's upward movement, the second PET layer fiber is pulled out first to form the second filament (average length 18mm), and then the first PET layer fiber is pulled out to form the first filament (average length 12mm). The filament originates from the PET layer itself.

[0032] Step 4: Make the first filament and the second filament entangle or intertwine with each other in the activated carbon resin layer.

[0033] After the needle is completely withdrawn from the upper surface, the fibers automatically intertwine in the pores of the resin felt due to elastic rebound, forming interlocking knots; each needle independently forms an entanglement structure.

[0034] Step 5: Repeat the above puncture and hooking operations at multiple points to form a glue-free connection.

[0035] The needle-punching frequency is set at 60 times / minute, the fabric advance speed at 6cm / minute, and the needle-punching path is a transverse serpentine pattern with a longitudinal spacing of 15mm and a transverse spacing of 10mm; the resulting density is approximately 66 dots / dm³. 2 The uniform needle-punched dot matrix was formed; after running continuously for 30 minutes, it was rolled up to obtain a carbon fiber reinforced roll material with a width of 28cm and a length of 1m.

[0036] Example 3: Pilot-scale preparation of wide-width continuous products using a dual-needle plate automated acupuncture machine Step 1: Provide a first PET layer, a second PET layer, and an activated carbon resin layer disposed between the two.

[0037] Select 55g / m 2 1. PET nonwoven fabric with a width of 1.6m is used as the first PET layer and the second PET layer; resin fiber felt containing activated carbon powder (mass fraction 68%) is selected, with a thickness of 2.8mm and a width of 1.6m; the three rolls are unwound simultaneously, and the tension is controlled at 80N / roll.

[0038] Step 2: Use a special needle to puncture the three layers in sequence.

[0039] Use a double-needle plate needle punching machine (4000 needles on the upper needle plate), each hook needle tip has a one-way hook-shaped structure (hook depth 0.35mm); set the puncture depth to 50mm, and the needle tip protrudes 4mm from the lower surface.

[0040] Step 3: Use a special needle to hook out the first and second threads.

[0041] After the upper needle plate descends to the bottom dead center, a 20Hz micro-vibration is applied for 1 second to enhance the fiber hooking efficiency; when it ascends, the second filament (average 16mm) and the first filament (average 11mm) are pulled out, and the fibers are derived from the PET layer body.

[0042] Step 4: Make the two threads entangle in the activated carbon resin layer.

[0043] After the stripping plate helps to detach the fibers, the fibers intertwine inside the resin felt to form figure-eight fiber bridges, with each needle forming an independent bridging point.

[0044] Step 5: Repeat at multiple points to form a non-adhesive carbon cloth.

[0045] Needle density 12 needles / cm 2 Fabrication speed 2.5 m / min, total needle density 120 points / cm² 2 Then, it is pressed flat by an 80℃ heat-setting roller (pressure 0.4MPa) to obtain a continuous carbon fiber cloth with a width of 1.55m.

[0046] Example 4: Mass production of high-load carbon fiber reinforced cloth on a high-speed four-needle plate industrial production line Step 1: Provide three layers of material.

[0047] Select 45g / m 2 PET nonwoven fabric with a width of 2.1m is used as the first PET layer and the second PET layer; resin fiber felt containing 75wt% activated carbon powder is selected, with a thickness of 1.8mm and a width of 2.1m; servo synchronous unwinding, with a deviation of ≤±2mm.

[0048] Step 2: Puncture with a special needle.

[0049] High-speed four-needle plate needle thread is used, and the hook is a titanium alloy three-hook structure; the total puncture depth is 42mm.

[0050] Step 3: Draw the silk threads.

[0051] The upper and lower needle plates work alternately. The upper needle plate pulls out the second thread (average 14mm), and the lower needle plate pulls out the first thread (average 10mm), thus pulling the thread in both directions.

[0052] Step 4: Tangle the silk threads.

[0053] The fibers form a two-way interlocking mesh structure within the activated carbon layer, with a single-point tensile strength ≥1.2N.

[0054] Step 5: Repeat at multiple points to form a glue-free bond.

[0055] Total stitch density 180 dots / cm 2Linear speed 5m / min; online laser detection of pinhole consistency, followed by a 60℃ infrared drying tunnel, automatic winding, yielding 2.05m wide carbon fiber reinforced cloth, with a production capacity of 600m. 2 / h.

[0056] Comparative example: Preparation of carbon fiber reinforced cloth using conventional hot melt adhesive bonding method (same size as Example 1) Step 1: Take the same three-layer material as in Example 1 (15cm × 15cm). Step 2: Evenly spray hot melt adhesive (EVA) onto the lower surface of the first PET layer, coating amount 30g / m². 2 Pre-dry at 80℃ for 30 seconds until semi-dry. Step 3: Stack the activated carbon resin layer and the second PET layer, and press them together with a hot roller (120℃, 0.6MPa) for 10 seconds. Step 4: Cool and set to obtain the carbon cloth sandwiched by adhesive method.

[0057] Table 1

[0058] As shown in the table above, as the needle-punching process gradually upgraded from manual small-scale production (Example 1) to high-speed industrial production (Example 4), the peel strength of the carbon-reinforced cloth continuously increased from 12.4 N / 5cm to 22.6 N / 5cm, far exceeding the 16.8 N / 5cm of the control example using the traditional adhesive method; the activated carbon shedding rate gradually decreased from 0.8% to 0.2%, significantly better than the 3.5% of the control example; VOC emissions remained below the detection limit, demonstrating completely adhesive-free environmental protection characteristics; PM2.5 filtration efficiency gradually increased to 99.97% with increasing needle density, and although air permeability decreased slightly, it remained at a high level. Overall, this invention's adhesive-free needle-punching process is superior to the traditional adhesive method in terms of strength, durability, environmental friendliness, and filtration performance, and possesses excellent adaptability for large-scale production.

[0059] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A process for manufacturing carbon fiber reinforced cloth, characterized in that, Includes the following steps: A first PET layer, a second PET layer, and an activated carbon resin layer disposed between the two are provided; A special needle is used to sequentially puncture the first PET layer, the activated carbon resin layer, and the second PET layer; Through the movement of the special needle, some fibers are hooked out from the first PET layer to form a first filament, and some fibers are hooked out from the second PET layer to form a second filament; The first and second filaments are entangled or intertwined in the activated carbon resin layer. The above puncture and hooking operations are repeated at multiple points, so that the first PET layer and the second PET layer are connected without glue through the first filament and the second filament to form carbon fiber cloth.

2. The carbon fiber reinforced cloth manufacturing process according to claim 1, characterized in that, The tip of the specially designed needle is equipped with barbs or hook-like structures for hooking fibers.

3. The carbon fiber reinforced cloth manufacturing process according to claim 1, characterized in that, The activated carbon resin layer is a resin fiber felt mixed with activated carbon powder.

4. The carbon fiber reinforced cloth manufacturing process according to claim 1, characterized in that, The first filament and the second filament are each composed of their respective PET layer body fibers.

5. The carbon fiber reinforced cloth manufacturing process according to claim 1, characterized in that, The puncture operation is repeated at multiple points to form a uniformly distributed array of needle puncture points.

6. A carbon fiber reinforced cloth, characterized in that, Made by the manufacturing process described in any one of claims 1 to 5.

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