A wet preparation process of a core, the core and a production equipment thereof
By using a wet-process manufacturing method to bond polymer resins in a wetted state of nonwoven fabric and then drying them by contact heating, the problem of poor air permeability of traditional cores is solved, and a high-air-permeability and stable core without adhesives is achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- FOSHAN MEIDENG PAPER PRODS
- Filing Date
- 2023-11-27
- Publication Date
- 2026-07-24
Smart Images
Figure CN117426929B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of hygiene products, and in particular to a wet preparation process for a core, the core itself, and production equipment thereof. Background Technology
[0002] The core refers to the internal structure of hygiene products such as diapers or sanitary napkins, which is used to absorb and store water. Traditionally, the core uses fluff pulp to achieve the function of water absorption. In recent years, water absorption structures composed of non-woven fabric and polymer resin have become more popular, effectively reducing clumping.
[0003] The core is typically manufactured by bonding nonwoven fabric and polymer resin with adhesives. For example, adhesive is first applied to the surface of the nonwoven fabric to form an adhesive layer, then polymer resin is injected into the adhesive layer, and finally the two layers of nonwoven fabric are bonded together to form the core.
[0004] However, while the use of adhesives can bring a smooth and stable effect to the core, it is often found that the application of adhesives on nonwoven fabrics may clog the mesh, resulting in poor air permeability and affecting the user experience. Summary of the Invention
[0005] To improve the air permeability of the core, this application provides a wet preparation process for the core, as well as the core and its production equipment.
[0006] Firstly, the wet preparation process for a core provided in this application adopts the following technical solution:
[0007] A wet manufacturing process for a core includes the following steps:
[0008] S1. Unwind multiple nonwoven fabrics and pull the nonwoven fabrics, then wet the nonwoven fabrics with water;
[0009] S2. The adjacent nonwoven fabrics move closer to each other, and the polymer resin enters between the adjacent nonwoven fabrics, pressing the adjacent nonwoven fabrics together to form a pre-formed core.
[0010] S3. The preformed core is pulled, and the preformed core is heated in contact with the heating source. The heating source makes the preformed core tensile, and the preformed core is dried to form a core.
[0011] S4. Wind up the core to complete the wet preparation of the core.
[0012] By adopting the above technical solution, when the nonwoven fabric is wet, the polymer resin falls onto the surface of the nonwoven fabric and absorbs water appropriately, becoming an adhesive state that can bond with the nonwoven fabric. After drying, it can achieve the composite of adjacent nonwoven fabrics and the nonwoven fabric and polymer resin, thus eliminating the need for adhesives. Moreover, the internal structure of the core is more uniform, solving the problem of complex internal structure and blocked pores caused by adhesives in the past, and improving air permeability while ensuring stability.
[0013] The pre-formed core is heated and dried by contact heating to complete the forming of the pre-formed core. The heating source tensions the pre-formed core, which not only makes the pre-formed core stick tightly to the heating source, squeezes out water, increases the contact area and improves the drying efficiency, but also generates pressure to further bond the inner side of the non-woven fabric with the polymer resin, thereby obtaining a core with excellent structural stability and air permeability.
[0014] Optionally, in step S3, the heating source is a heating roller, the heating temperature of the preformed core by the heating roller is 90-105°C, and the traction speed of the preformed core when passing through the heating roller is 7-11 m / min.
[0015] By adopting the above technical solution, the roller structure can provide sufficient contact area and tension to the pre-formed core. The degree of drying and heat sealing can be controlled by controlling the heating temperature and traction time. If the degree of drying and heat sealing is too low, the moisture will not be dried, affecting the water absorption capacity. If the degree of drying and heat sealing is too high, the internal structure of the core will be damaged, the stability will be poor, and the core will easily clump after use.
[0016] Optionally, in step S1, water is sprayed into contact with the nonwoven fabric to wet it.
[0017] By adopting the above technical solution, the spraying method can allow water to penetrate into the interior of the nonwoven fabric structure, so that the adhesive state of the polymer resin after falling onto the surface of the nonwoven fabric will not be too diluted or too thick, thereby improving the bonding stability between the polymer resin and the nonwoven fabric.
[0018] Optionally, a surfactant is added to the water to wet the nonwoven fabric. The surfactant is prepared by long-chain alkylphenol polyoxyethylene ether, long-chain alkylbenzene sulfonate sodium and Tween, and the mass ratio of the long-chain alkylphenol polyoxyethylene ether, long-chain alkylbenzene sulfonate sodium and Tween is 1:(0.44~0.52):(2.5~2.8).
[0019] By adopting the above technical solution, the surfactant modifies the surface of the nonwoven fabric to be more hydrophilic, thereby increasing the affinity between the nonwoven fabric surface and the polymer resin. Combining the wetting and hydrophilic modification steps is not only highly efficient, but also ensures that the structure of the alkylphenol polyoxyethylene ether in the surfactant is in full contact with the polymer resin, resulting in higher stability of water storage in the core after drying.
[0020] Optionally, the long-chain alkylphenol polyoxyethylene ether is one or both of nonylphenol polyoxyethylene ether and dodecylphenol polyoxyethylene ether.
[0021] Optionally, the long-chain alkylbenzene sulfonate sodium is dodecylbenzene sulfonate sodium.
[0022] Optionally, the Tween is one or both of Tween-60 and Tween-80.
[0023] Optionally, the weight ratio of the surfactant to water is 1:(80-100), and the temperature of the liquid formed after adding the surfactant to the water is 70-80°C.
[0024] By adopting the above technical solution, an appropriate amount of surfactant can help improve the hydrophilicity of nonwoven fabrics.
[0025] Optionally, the amount of the polymer resin used is 160-200 g / m³. 2 The polymer resin is prepared by acrylic acid, acrylamide, vinyl 2-ethylhexanoate, N,N'-methylenebisacrylamide, initiator and bentonite, wherein the weight ratio of acrylic acid, acrylamide, vinyl 2-ethylhexanoate, N,N'-methylenebisacrylamide, initiator and bentonite is 1:(1~1.5):(0.18~0.32):(0.05~0.08):(0.01~0.05):(0.08~0.12).
[0026] By adopting the above technical solution, bentonite is incorporated into the polymer resin, along with a small amount of hydrophobic 2-ethylhexanoate, which affects the polymerization and molding of the polymer resin. This makes the interior of the polymer resin appropriately loose, resulting in better water absorption and air permeability. Furthermore, during the tensioning and drying process of the pre-formed core, the loose structure allows the hydrophilic groups of the surfactant to enter and bind inside the polymer resin, further improving the stability of the core structure.
[0027] Optionally, the preparation method of the polymer resin is as follows: alkali and water are added to acrylic acid to adjust the pH to 6.5-7.5, then acrylamide, vinyl 2-ethylhexanoate, N,N'-methylenebisacrylamide and bentonite are added, the mixture is heated to 65-75°C, and an initiator is added while stirring. After the initiator is added, the reaction continues for 1.5-2.5 hours. After the reaction is completed, the mixture is cooled, filtered, and the filter body is collected. The filter body is washed and dried to obtain the polymer resin.
[0028] By adopting the above technical solution, polymer resin is promoted to polymerize and form on the surface of bentonite by initiating polymerization, thereby obtaining a suitable polymer resin structure.
[0029] Secondly, the core provided in this application adopts the following technical solution:
[0030] A core comprising a polymer resin and multiple layers of nonwoven fabric, wherein the polymer resin is located between adjacent layers of nonwoven fabric.
[0031] By adopting the above technical solution, the core has good air permeability, water absorption and stability.
[0032] Thirdly, the wet production equipment for cores provided in this application adopts the following technical solution:
[0033] A wet production apparatus for a core includes an unwinding device, a wetting device, a blanking device, a pressing device, a drying device, and a winding device. The wetting device is used to wet the nonwoven fabric, the blanking device is used to allow polymer resin to fall onto the surface of the nonwoven fabric, the pressing device is used to press adjacent nonwoven fabrics together, and the drying device is used to dry the moisture.
[0034] In summary, this application has the following beneficial effects:
[0035] 1. When the nonwoven fabric is wet, the polymer resin will absorb moisture and become adhesive after falling onto the surface of the nonwoven fabric. It can then bond with the nonwoven fabric. After drying, it can achieve the composite of adjacent nonwoven fabrics and the nonwoven fabric and polymer resin, thus eliminating the need for adhesives. The internal structure of the core is more uniform, solving the problem of complex internal structure and pore blockage caused by adhesives in the past. It improves air permeability while ensuring stability.
[0036] 2. The pre-formed core is heated and dried by contact heating to complete the forming of the pre-formed core. The heating source makes the pre-formed core tensile, which not only makes the pre-formed core stick tightly to the heating source, squeeze out water, increase the contact area and improve the drying efficiency, but also generates pressure to further bond the inner side of the non-woven fabric with the polymer resin, thereby obtaining a core with excellent structural stability and air permeability. Attached Figure Description
[0037] Figure 1 This is a plan view of the wet production equipment for the core of this application.
[0038] Figure 2 This is a plan view of the wetting device, unloading device, and pressing device of the production equipment in this application.
[0039] Explanation of reference numerals in the attached figures:
[0040] 1. Nonwoven fabric; 11. Preformed core; 2. Unwinding device; 3. Wetting device; 31. Water spray head; 4. Feeding device; 41. Feeding bin; 5. Pressing device; 51. Pressing roller; 6. Drying cylinder; 7. Winding device. Detailed Implementation
[0041] The following is in conjunction with the appendix Figure 1 This application will be described in further detail.
[0042] Preparation Example 1
[0043] Preparation methods of polymer resins:
[0044] Dissolve 10g of potassium persulfate in 200mL of water to obtain an initiator solution.
[0045] 1000g of acrylic acid was added to 15L of water, NaOH was added and the pH was adjusted to 6.5, then 1000g of acrylamide, 180g of 2-ethylhexanoate, 50g of N,N'-methylenebisacrylamide and 80g of bentonite were added. The mixture was heated to 75℃, and the initiator solution was added dropwise while stirring. After the initiator solution was completely added, the reaction continued for 1.5h. After the reaction was completed, the mixture was cooled, filtered and the filter body was collected. The filter body was washed with water and ethanol and dried to obtain the polymer resin.
[0046] Preparation Example 2
[0047] Preparation methods of polymer resins:
[0048] Dissolve 50g of potassium persulfate in 300mL of water to obtain an initiator solution.
[0049] 1000g of acrylic acid was added to 15L of water, NaOH was added and the pH was adjusted to 7.5, then 1500g of acrylamide, 320g of 2-ethylhexanoate, 80g of N,N'-methylenebisacrylamide and 120g of bentonite were added. The mixture was heated to 65℃, and the initiator solution was added dropwise while stirring. After the initiator solution was completely added, the reaction continued for 2.5h. After the reaction was completed, the mixture was cooled, filtered and the filter body was collected. The filter body was washed with water and ethanol and dried to obtain the polymer resin.
[0050] Preparation Example 3
[0051] Preparation methods of polymer resins:
[0052] Dissolve 10g of potassium persulfate in 200mL of water to obtain an initiator solution.
[0053] 1000g of acrylic acid was added to 15L of water, NaOH was added and the pH was adjusted to 6.5, then 1000g of acrylamide, 50g of N,N'-methylenebisacrylamide and 80g of bentonite were added, and the mixture was heated to 75℃. The initiator solution was added dropwise while stirring. After the initiator solution was added, the reaction continued for 1.5h. After the reaction was completed, the mixture was cooled, filtered and the filter body was collected. The filter body was washed with water and ethanol and dried to obtain the polymer resin.
[0054] Preparation Example 4
[0055] Preparation methods of polymer resins:
[0056] Dissolve 10g of potassium persulfate in 200mL of water to obtain an initiator solution.
[0057] 1000g of acrylic acid was added to 15L of water, NaOH was added and the pH was adjusted to 6.5, then 1000g of acrylamide, 180g of 2-ethylhexanoate and 50g of N,N'-methylenebisacrylamide were added. The mixture was heated to 75℃, and the initiator solution was added dropwise while stirring. After the initiator solution was completely added, the reaction was continued for 1.5h. After the reaction was completed, the mixture was cooled, filtered and the filter body was collected. The filter body was washed with water and ethanol and dried to obtain the polymer resin.
[0058] Example 1
[0059] A wet manufacturing process for a core includes the following steps:
[0060] S1. Unwind multiple nonwoven fabrics and pull the nonwoven fabrics. In this embodiment, there are two nonwoven fabrics. The nonwoven fabrics are unwound by an unwinding device, and there are two unwinding devices. After the nonwoven fabrics are pulled to the wetting device, the wetting device sprays water onto the nonwoven fabrics to wet them.
[0061] S2. Two adjacent nonwoven fabrics move closer to each other under traction and move together to the bottom of the feeding device, which contains the polymer resin prepared in Preparation Example 1. The polymer resin falls between the two adjacent nonwoven fabrics, with a polymer resin dosage of 160 g / m². 2 Then, the pressing device presses two adjacent nonwoven fabrics together to form a pre-formed core.
[0062] S3. Traction of the pre-formed core, the pre-formed core is heated in contact with the heating source, the heating source includes multiple heating rollers, the heating rollers are specifically drying cylinder structures, the pre-formed core passes around the multiple heating sources in sequence under traction, the heating temperature of the pre-formed core by the heating rollers is 90℃, the traction speed of the pre-formed core when passing the heating rollers is 7m / min, the heating source makes the pre-formed core tensile, and the pre-formed core is dried to form the core.
[0063] S4. The winding device winds up the core, completing the wet preparation of the core.
[0064] Example 2
[0065] A wet manufacturing process for a core includes the following steps:
[0066] S1. Unwind multiple nonwoven fabrics and pull the nonwoven fabrics. In this embodiment, there are two nonwoven fabrics. The nonwoven fabrics are unwound by an unwinding device, and there are two unwinding devices. After the nonwoven fabrics are pulled to the wetting device, the wetting device sprays water onto the nonwoven fabrics to wet them.
[0067] S2. Two adjacent nonwoven fabrics move closer to each other under traction and move together to the bottom of the feeding device, which contains the polymer resin prepared in Preparation Example 1. The polymer resin falls between the two adjacent nonwoven fabrics, with a polymer resin dosage of 200 g / m². 2 Then, the pressing device presses two adjacent nonwoven fabrics together to form a pre-formed core.
[0068] S3. Traction of the pre-formed core, the pre-formed core is heated in contact with the heating source, the heating source includes multiple heating rollers, the heating rollers are specifically drying cylinder structures, the pre-formed core passes around the multiple heating sources in sequence under traction, the heating temperature of the pre-formed core by the heating rollers is 105℃, the traction speed of the pre-formed core when passing the heating rollers is 11m / min, the heating source makes the pre-formed core tensile, and the pre-formed core is dried to form the core.
[0069] S4. The winding device winds up the core, completing the wet preparation of the core.
[0070] Example 3
[0071] The difference between this embodiment and Embodiment 1 is that step S1 is different.
[0072] S1. Unwind multiple nonwoven fabrics and pull the nonwoven fabrics. In this embodiment, there are two nonwoven fabrics. The nonwoven fabrics are unwound by an unwinding device, and there are two unwinding devices. After the nonwoven fabrics are pulled to the wetting device, the wetting device sprays a mixture of water and surfactant onto the nonwoven fabric. The temperature of the mixture is 70°C, which wets the nonwoven fabric.
[0073] The surfactant to water weight ratio in the mixture is 1:80. The surfactant consists of 100g dodecylphenol polyoxyethylene ether, 44g sodium dodecylbenzenesulfonate, and 250g Tween-80.
[0074] Example 4
[0075] The difference between this embodiment and Embodiment 1 is that steps S1 and S2 are different.
[0076] S1. Unwind multiple nonwoven fabrics and pull the nonwoven fabrics. In this embodiment, there are two nonwoven fabrics. The nonwoven fabrics are unwound by an unwinding device, and there are two unwinding devices. After the nonwoven fabrics are pulled to the wetting device, the wetting device sprays a mixture of water and surfactant onto the nonwoven fabric. The temperature of the mixture is 80°C, which wets the nonwoven fabric.
[0077] The surfactant to water weight ratio in the mixture is 1:100. The surfactant consists of 100g dodecylphenol polyoxyethylene ether, 52g sodium dodecylbenzenesulfonate, and 280g Tween-80.
[0078] S2. Two adjacent nonwoven fabrics move closer to each other under traction and move together to the bottom of the feeding device. The feeding device contains the polymer resin prepared in Preparation Example 2. The polymer resin falls between the two adjacent nonwoven fabrics. Then the pressing device presses the two adjacent nonwoven fabrics together to form a preformed core.
[0079] Example 5
[0080] The difference between this embodiment and Embodiment 1 is that step S1 is different.
[0081] S1. Unwind multiple nonwoven fabrics and pull the nonwoven fabrics. In this embodiment, there are two nonwoven fabrics. The nonwoven fabrics are unwound by an unwinding device, and there are two unwinding devices. After the nonwoven fabrics are pulled to the wetting device, the wetting device sprays a mixture of water and surfactant onto the nonwoven fabric. The temperature of the mixture is 70°C, which wets the nonwoven fabric.
[0082] The surfactant to water weight ratio in the mixture is 1:80. The surfactant consists of 100g polyoxyethylene dodecyl ether, 44g sodium dodecylbenzenesulfonate, and 250g Tween-80.
[0083] Example 6
[0084] The difference between this embodiment and embodiment 3 is that steps S1 and S2 are different.
[0085] S1. Unwind multiple nonwoven fabrics and pull the nonwoven fabrics. In this embodiment, there are two nonwoven fabrics. The nonwoven fabrics are unwound by an unwinding device, and there are two unwinding devices. After the nonwoven fabrics are pulled to the wetting device, the wetting device sprays a mixture of water and surfactant onto the nonwoven fabric. The temperature of the mixture is 70°C, which wets the nonwoven fabric.
[0086] The surfactant to water weight ratio in the mixture is 1:80. The surfactant consists of 100g dodecylphenol polyoxyethylene ether, 44g sodium dodecylbenzenesulfonate, and 250g Tween-80.
[0087] S2. Two adjacent nonwoven fabrics move closer to each other under traction and move together to the bottom of the feeding device. The feeding device contains the polymer resin prepared in Preparation Example 3. The polymer resin falls between the two adjacent nonwoven fabrics. Then the pressing device presses the two adjacent nonwoven fabrics together to form a preformed core.
[0088] Example 7
[0089] The difference between this embodiment and Embodiment 1 is that steps S1 and S2 are different.
[0090] S1. Unwind multiple nonwoven fabrics and pull the nonwoven fabrics. In this embodiment, there are two nonwoven fabrics. The nonwoven fabrics are unwound by an unwinding device, and there are two unwinding devices. After the nonwoven fabrics are pulled to the wetting device, the wetting device sprays a mixture of water and surfactant onto the nonwoven fabric. The temperature of the mixture is 70°C, which wets the nonwoven fabric.
[0091] The surfactant to water weight ratio in the mixture is 1:80. The surfactant consists of 100g dodecylphenol polyoxyethylene ether, 44g sodium dodecylbenzenesulfonate, and 250g Tween-80.
[0092] S2. Two adjacent nonwoven fabrics move closer to each other under traction and move together to the bottom of the feeding device. The feeding device contains the polymer resin prepared in Preparation Example 4. The polymer resin falls between the two adjacent nonwoven fabrics. Then the pressing device presses the two adjacent nonwoven fabrics together to form a preformed core.
[0093] Comparative Example 1
[0094] The difference between this embodiment and Embodiment 1 is that step S3 is different.
[0095] S3. The pre-formed core enters the belt dryer, which includes a conveyor belt and a dryer. The pre-formed core is supported and driven into the dryer by the conveyor belt, and the conveyor belt does not tension the pre-formed core. The hot air circulation in the dryer dries the pre-formed core. The internal temperature of the dryer is 90℃. The speed of the pre-formed core passing through the dryer is 7m / min. The pre-formed core is dried to form a core.
[0096] Comparative Example 2
[0097] A method for preparing a core includes the following steps:
[0098] S1. Unwind two rolls of nonwoven fabric and coat one side of the nonwoven fabric with EVA hot melt adhesive at a rate of 10g / m². 2 .
[0099] S2. The polymer resin prepared in Example 1 was spread onto one side of a nonwoven fabric coated with EVA hot melt adhesive, at an amount of 160 g / m². 2.
[0100] S3. Bond the two nonwoven fabrics together to obtain the core.
[0101] Performance testing
[0102] Air permeability test: The air permeability of the core was tested in accordance with GB / T 5453-1997 "Determination of air permeability of textile fabrics", and the test results are recorded in Table 1.
[0103] Stability test: Take 100 mL of physiological saline (0.9% mass concentration) and heat it to 40℃. Then add the physiological saline to the core and place the core in a test chamber at 40±1℃ and 85±1%RH for 10 min. Then take out the core and perform the following pulling and swinging actions: The tester holds both ends of the core with one hand and swings one end of the core with one hand, repeating 10 times. Then stretches both ends of the core back and forth with both hands, repeating 10 times. Then rubs the core with both hands, repeating 10 times. The above is recorded as one set of actions. Repeat multiple sets of actions and record the number of sets of actions when the core shows clumping. The more sets of actions, the more stable the core structure. Record in Table 1.
[0104] Absorbency test: The core was tested for absorption rate and rewetting amount in accordance with QB / T 5650-2021 "Composite absorbent core for disposable paper sanitary products". The test results are recorded in Table 1.
[0105] Table 1
[0106] Air permeability (mm / s) Number of sets of pulling and swinging motions when forming a ball Absorption rate (g / g) Recirculation rate (g) Example 1 1885 6 20.6 3.1 Example 2 1929 6 20.4 3.0 Example 3 2089 7 21.6 2.2 Example 4 2041 7 21.4 2.4 Example 5 2065 6 21.3 4.0 Example 6 1740 4 19.5 3.6 Example 7 1792 4 19.0 3.7 Comparative Example 1 1576 1 14.2 6.8 Comparative Example 2 1337 6 16.8 4.5
[0107] Based on the analysis of the test results of Examples 1-2 and Comparative Example 2, compared with the core prepared by adhesive, the core prepared by the wet preparation process of this application has significantly improved air permeability, and the absorption rate and reabsorption amount are also improved. In addition, it can also withstand the pulling and shaking action simulated by external force, indicating that the wet preparation process of this application can produce a core that is breathable, stable and has good water absorption and storage capacity.
[0108] Based on the analysis of the test results of Example 1 and Comparative Example 1, compared with the method of drying by linear hot air, the method of drying by tensioning and heat bonding with a heating source as described in this application significantly improves the various performance characteristics of the core product, especially making the core structure more stable.
[0109] Based on the analysis of the test results of Examples 1 and 3-5, compared with simply wetting the nonwoven fabric with water, using the surfactant of this application to impregnate the nonwoven fabric helps to improve the bonding stability between the nonwoven fabric and the polymer resin, thereby promoting the water storage stability of the core.
[0110] Based on the analysis of the test results of Examples 1 and 6-7, compared with polymer resins lacking 2-ethylhexanoate or bentonite, the polymer resin of this application exhibits good performance in terms of air permeability and stability.
[0111] A wet production equipment for cores, such as Figure 1 and Figure 2 As shown, a wet production equipment for a core includes an unwinding device 2, a wetting device 3, a blanking device 4, a pressing device 5, a drying device, and a winding device 7.
[0112] There are two unwinding devices 2, which are used to unwind the nonwoven fabric 1, so that the two nonwoven fabrics 1 can be unwound separately.
[0113] The pressing device 5 includes two pressing rollers 51, which rotate in opposite directions and have a gap between them. After the two nonwoven fabrics 1 are unwound, they are conveyed toward the two pressing rollers 51 and pass around the pressing rollers 51. The two nonwoven fabrics 1 pass through the gap between the two pressing rollers 51 at the same time.
[0114] The wetting device 3 includes multiple spray heads 31, which are located above the pressing roller 51. The liquid sprayed from the spray heads 31 falls onto the nonwoven fabric 1 located on the pressing roller 51. The liquid is water or a mixture of water and surfactant, thereby wetting the nonwoven fabric 1.
[0115] The feeding device 4 includes a feeding bin 41, which is located above the pressing rollers 51 and between the two pressing rollers 51. The feeding bin 41 is used to hold polymer resin, and the feeding bin 41 allows the polymer resin to fall onto the nonwoven fabric 1. After the polymer resin falls onto the nonwoven fabric 1, the rotation of the two pressing rollers 51 causes the two nonwoven fabrics 1 to press together with the polymer resin to form a pre-formed core 11.
[0116] The drying device includes multiple drying cylinders 6. The pre-formed core 11 passes around the multiple drying cylinders 6 in sequence. The drying cylinders 6 provide tension force to the pre-formed core 11 and heat and dry the pre-formed core 11 to form a core.
[0117] The dried core enters the winding device 7 for winding, completing the wet preparation of the core.
[0118] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this specific embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.
Claims
1. A wet preparation process for a core, characterized in that: Includes the following steps: S1. Unwind multiple nonwoven fabrics and pull the nonwoven fabrics, then wet the nonwoven fabrics with water; In step S1, water is sprayed onto the non-woven fabric to wet it. S2. The adjacent nonwoven fabrics move closer to each other, and the polymer resin enters between the adjacent nonwoven fabrics, pressing the adjacent nonwoven fabrics together to form a pre-formed core. S3. The preformed core is pulled, and the preformed core is heated in contact with the heating source. The heating source makes the preformed core tensile, and the preformed core is dried to form a core. In step S3, the heating source is a heating roller, the heating temperature of the preformed core by the heating roller is 90~105℃, and the traction speed of the preformed core when passing through the heating roller is 7~11m / min; S4. Wind up the core to complete the wet preparation of the core; A surfactant is added to the water to wet the nonwoven fabric. The surfactant is prepared by long-chain alkylphenol polyoxyethylene ether, long-chain alkylbenzene sulfonate sodium and Tween. The mass ratio of long-chain alkylphenol polyoxyethylene ether, long-chain alkylbenzene sulfonate sodium and Tween is 1:(0.44~0.52):(2.5~2.8). The weight ratio of the surfactant to water is 1:(80~100), and the temperature of the liquid formed after adding the surfactant to the water is 70~80℃; The long-chain alkylphenol polyoxyethylene ether is one or both of nonylphenol polyoxyethylene ether and dodecylphenol polyoxyethylene ether; the long-chain alkylbenzene sulfonate sodium is dodecylbenzene sulfonate sodium. The amount of the polymer resin used is 160~200g / m³. 2 The polymer resin is prepared by acrylic acid, acrylamide, vinyl 2-ethylhexanoate, N,N'-methylenebisacrylamide, initiator and bentonite, wherein the weight ratio of acrylic acid, acrylamide, vinyl 2-ethylhexanoate, N,N'-methylenebisacrylamide, initiator and bentonite is 1:(1~1.5):(0.18~0.32):(0.05~0.08):(0.01~0.05):(0.08~0.12).
2. The wet preparation process of a core according to claim 1, characterized in that: The preparation method of the polymer resin is as follows: alkali and water are added to acrylic acid to adjust the pH to 6.5-7.5, then acrylamide, vinyl 2-ethylhexanoate, N,N'-methylenebisacrylamide and bentonite are added, the mixture is heated to 65-75℃, and an initiator is added while stirring. After the initiator is added, the reaction continues for 1.5-2.5 hours. After the reaction is completed, the mixture is cooled, filtered and the filter body is collected. The filter body is washed and dried to obtain the polymer resin.
3. A core, characterized in that: The core is prepared by a wet process according to any one of claims 1-2, comprising a polymer resin and multiple layers of nonwoven fabric, wherein the polymer resin is located between adjacent layers of nonwoven fabric.