Preparation method of ultra-soft coating abrasive cloth

Abstract

The invention discloses a preparation method of ultra-soft coating abrasive cloth, and particularly relates to the technical field of abrasive cloth preparation, the preparation method comprises the following steps: S1, pretreatment of a base material; s2, primer coating is carried out; s3, electrostatic sand planting; s4, coating and curing surface glue; s5, preparing and curing a multifunctional coating; and S6, carrying out finished product post-treatment. According to the invention, through targeted modification of the pure polyester gray fabric, the adhesive force of the coating is greatly improved while the super-soft fitting property is maintained; by means of the sand planting technology, both coarse grinding materials and fine grinding materials can achieve high and uniform sand planting density, so that the excellent cutting efficiency is obtained, meanwhile, the nanometer aluminum oxide enhanced surface glue is combined, the grinding material falling-off rate is extremely low, and the product durability is greatly improved; through a compound coating of nano silicon dioxide, magnesium hydroxide and polytetrafluoroethylene micro powder, the functions of high temperature resistance, high flame retardance and blockage resistance are synchronously achieved, and the problems that a traditional product is single in performance and limited in scene are solved.

Description

Technical Field

[0001] This invention relates to the field of abrasive cloth preparation technology, and more specifically, to a method for preparing ultra-soft coated abrasive cloth. Background Technology

[0002] As a basic consumable, the performance of abrasive cloth directly determines processing efficiency, surface quality, and overall cost. For a long time, the market has mainly relied on two types of products: traditional abrasive cloth with high-strength industrial fabric (such as heavy cotton canvas or synthetic fiber blended fabric) as the base material, and dry abrasive paper with a special paper base material. Traditional abrasive cloth benefits from the toughness and density of its base material, exhibiting excellent durability and environmental adaptability in high-intensity, high-load coarse grinding scenarios such as grinding machine tool castings and removing rust from steel structures. However, the inherent rigidity of its base material results in extremely poor adhesion, making it unsuitable for precision grinding of complex curved surfaces. Furthermore, its rough surface easily leads to uneven abrasive distribution and difficulty in chip removal, often resulting in uneven grinding, clogging, and low processing efficiency and surface finish.

[0003] To meet the precision polishing needs of industries such as automotive, electronics, and furniture, dry sandpaper has emerged. It uses a thin and soft paper base and achieves high-density, orderly arrangement of abrasive particles through electrostatic sanding technology, thus possessing excellent adhesion, high cutting efficiency, and good surface finish. However, the paper base material has fatal flaws such as weak mechanical strength, poor tear resistance, and insufficient resistance to damp heat, making it completely unable to withstand heavy-duty grinding. Moreover, it is extremely easy to break and deform in humid environments or at high temperatures generated by metal grinding, and its application is strictly limited to low-intensity precision operations.

[0004] To overcome these limitations, the industry has made numerous attempts, such as using cotton-polyester blended fabrics to balance strength and cost; adding single-function additives (such as flame retardants or antistatic agents) to the coating; or improving the sand-coating process. However, these improvements often come at the expense of other aspects, either failing to fundamentally resolve the contradiction between the substrate's softness and adhesion, or improving only one performance at the expense of others. A comprehensive abrasive cloth product that simultaneously possesses ultra-soft adhesion, high abrasive holding power, excellent temperature resistance and flame retardancy, and long-lasting anti-clogging properties has remained elusive. Furthermore, whether it's traditional abrasive cloth or... Dry abrasive paper often has relatively simple or coarse abrasive planting process parameters, failing to finely match them according to the physical characteristics of abrasive particle size (such as mass, specific surface area, and agglomeration). This can lead to coarse abrasive particles falling off prematurely due to poor embedding, while fine abrasive particles may affect the surface processing quality due to uneven distribution or agglomeration. Therefore, developing a preparation method that can adaptively adjust the core abrasive planting parameters according to the target abrasive particle size, thereby achieving optimal abrasive distribution and holding force for each particle size product, is of great significance for improving the overall performance and reliability of abrasive materials. Summary of the Invention

[0005] To overcome the above-mentioned defects of the prior art, the present invention provides a method for preparing ultra-soft coated abrasive cloth.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a method for preparing ultra-soft coated abrasive cloth, comprising the following steps: S1. Substrate Pretreatment: Using civilian clothing fiber fabric as the substrate, the following treatments are performed sequentially: S101, directional degreasing: In a 5%-6% sodium hydroxide solution, treat at 60-65℃ for 25-35 minutes with a bath ratio of 1:20. After degreasing, wash with water until the pH is 6.5-7.5. After drying, control the moisture content of the substrate to 6%-8%. S102, Twin-roll calendering: A combination of galvanized hard rollers and nitrile rubber elastic rollers is used to calender the fabric at 80-85℃ and 6-7MPa pressure, with a conveying speed of 2.5-3m / min. S103, Plasma Modification: For fine abrasive substrates of 200 mesh and above, treat with 350-450W power for 3-5 seconds in an atmosphere of argon to oxygen volume ratio of 9:1. S2. Primer Coating: Mix E-44 epoxy resin and 2123 phenolic resin at a mass ratio of 1:1, add 3%-5% xylene diluent (by mass of total resin) to adjust the viscosity to 2000-2500 mPas, and apply to the pretreated substrate surface using a doctor blade and roller coating process. Then pre-bake at 100-105℃ for 6-8 minutes to allow the primer to cure to 40%-50%. S3, Electrostatic Abrasive Coating: Selective abrasive coating for different particle size ranges. For 40-200 mesh coarse abrasives, under conditions of 30-35kV voltage and substrate tension of 60-70N / m, the abrasive planting time is 13-15s, and the abrasive planting density is 75 particles / cm³. 2 Embedding depth 50%; For fine abrasives of 200-5000 mesh, under conditions of 45-50kV voltage and substrate tension of 50-60N / m, sand planting for 8-10 seconds is performed, with a sand planting density of 120 grains / cm³. 2 Embedding depth 30%; S4. Topcoat Coating and Curing: A topcoat is applied to the substrate after sand planting. The topcoat is made by adding 1%-2% of the total mass of the topcoat to the base coat formula, and then drying it at 120℃ for 2 hours and ultrasonically dispersing it for 10 minutes. The coating thickness is controlled by a micro-concave roller coating process, and then cured at 125-130℃ for 25-30 minutes to achieve an overall curing degree of 90% for the abrasive layer. S5. Preparation and curing of multifunctional coating: Prepare a coating slurry containing acrylic resin, 5%-8% nano-silica, 10%-12% magnesium hydroxide and 1%-2% polytetrafluoroethylene micro powder by weight of the coating, and apply it to the topcoat layer using a high-pressure airless spraying process with a spraying pressure of 0.8-1.0 MPa. Then, perform a three-stage curing process: leveling at 120℃ for 5 min, curing at 150-160℃ for 15-20 min, and forced air cooling. S6. Finished product post-processing: The physical and functional properties of the cured sandpaper are tested. After passing the test, it is cut into specifications and packaged with moisture-proof materials.

[0007] As a further improvement to the technical solution of the present invention, the civilian clothing fiber fabric in S1 is a 100% polyester plain weave fabric that has undergone degreasing and calendering pretreatment. The yarn specifications of the polyester plain weave fabric are 75D / 36F FDY150D / 96F DTY, the warp density is 552 threads / inch, the weft density is 452 threads / inch, and the weight is 95-105g / m.

[0008] As a further improvement to the technical solution of the present invention, the electrode spacing of the plasma treatment in S103 is 5-8mm.

[0009] As a further improvement to the technical solution of the present invention, the scraper gap is 0.10-0.12mm when coating with coarse abrasive in S2, and 0.07-0.09mm when coating with fine abrasive.

[0010] As a further improvement to the technical solution of the present invention, the coarse abrasive in S3 is brown corundum, and the fine abrasive is ceramic abrasive; before sand planting, the abrasives need to be dried at 105-110℃ for 12-15 minutes to reduce the moisture content to 0.3%.

[0011] As a further improvement to the technical solution of the present invention, in step S4, the depth of the micro-concave roller cavity is 30-40m when applying coarse abrasive adhesive and the depth of the cavity is 20-30m when applying fine abrasive adhesive.

[0012] As a further improvement to the technical solution of the present invention, the solid content of the acrylic resin in S5 is 45%-50%, and the glass transition temperature is 50-60℃.

[0013] As a further improvement to the technical solution of the present invention, the coating slurry in S5 also contains a nano-silver antibacterial agent with a particle size of 20-50nm, accounting for 1%-2% of the total mass of the coating.

[0014] As a further improvement to the technical solution of the present invention, the resin system used in S2 and S4 is a water-based epoxy-acrylic composite resin system, and a solvent recovery device is provided in the coating and curing section.

[0015] As a further improvement to the technical solution of the present invention, sensors are installed at the key workstations of S1-S5, and process parameters are collected in real time through the PLC system and compared and adaptively adjusted with the preset process model.

[0016] The method for preparing ultra-soft coated abrasive cloth provided by this invention achieves breakthroughs in terms of softness, adhesion, wear resistance, durability, comprehensive functionality, and environmental friendliness through precise structural pretreatment of the substrate, abrasive layer construction, synergistic effect of multifunctional coating, and intelligent control of the process. Its technical effects are significantly superior to traditional abrasive cloth and dry sandpaper, specifically manifested in the following ways: 1. Through the synergistic effect of targeted degreasing and physical calendering, the processing aids on the substrate surface are removed, and the surface smoothness and fiber orientation are fundamentally improved, providing an ideal and stable adhesion interface for subsequent coatings. After plasma modification in a specific atmosphere, the substrate surface changes from hydrophobic to hydrophilic, and the number of polar functional groups increases significantly, which significantly enhances the chemical bonding force and physical anchoring force with the organic coating, overcoming the problem of coatings easily peeling off from flexible substrates. 2. Optimization of particle size adaptability in sand planting process: Addressing the significant differences in mass and volume between coarse and fine abrasives, this invention designs two completely independent systems of sand planting voltage, time, and tension parameters. For example, a relatively low voltage, a longer application time, and a higher substrate tension are used for coarse abrasives to ensure they can overcome their own weight and fully embed and achieve deep anchoring. For fine abrasives, a higher voltage, a shorter application time, and moderate tension are used to overcome their tendency to agglomerate using a strong electric field, achieving high-density, shallow, and uniform fixation. Through the synergistic control of these parameters and the pre-curing degree of the base adhesive, both coarse and fine abrasives can achieve high and uniform sand planting density, resulting in excellent cutting efficiency. Simultaneously, combined with a nano-alumina-reinforced topcoat, the abrasive shedding rate is extremely low, significantly improving product durability. 3. The nano-silica in the coating is uniformly dispersed in the resin matrix and combines with the acrylic resin during the curing process to form a stable composite structure. This effectively inhibits the thermal decomposition and softening tendency of the resin matrix, enabling the product to adapt to high-temperature scenarios such as welding and grinding of workpieces after heat treatment, which traditional coated abrasive cloths cannot handle. The added magnesium hydroxide flame retardant achieves a highly efficient and environmentally friendly flame retardant effect through multiple mechanisms such as endothermic decomposition, release of water vapor, and generation of magnesium oxide barrier when heated, enabling the product to reach a high flame retardant rating and greatly improving operational safety in flammable, explosive, or high-temperature spark environments. The introduced polytetrafluoroethylene micropowder, with its extremely low surface energy, makes it difficult for various abrasive particles to adhere to the coating surface, maintaining the continuous exposure and sharpness of the abrasive grains, significantly reducing cleaning downtime during processing, and improving continuous operation efficiency and surface finish consistency. This coating system has good compatibility and can be easily integrated with antibacterial agents such as nano-silver or other functional components, thereby meeting the additional requirements for product cleanliness and safety in special industries such as medical devices and electronic assembly. In summary, this invention uses civilian clothing fiber fabric to replace traditional industrial fabric, significantly reducing raw material costs. Its inherent fiber fineness and fabric structure provide excellent initial softness for the product. Specifically, by selecting low-cost, readily available civilian fabric with a good fiber structure, and then addressing its shortcomings as an industrial substrate through targeted pretreatment, an optimized substrate with low cost, ultra-softness, and high adhesion is obtained. Through the targeted pretreatment of this invention, it is successfully transformed into an abrasive cloth substrate with both ultra-softness and high interfacial bonding strength. This invention not only successfully integrates the durability of traditional abrasive cloth with the precision of dry sandpaper, but also, through material and process innovation, endows the product with new functions such as high-temperature resistance, flame retardancy, and anti-clogging, creating an ultra-soft coated abrasive cloth that can be widely used in high-end manufacturing, precision machining, and special working conditions. Attached Figure Description

[0017] Figure 1 This is a flowchart of the method of the present invention. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] As attached Figure 1 The method for preparing an ultra-soft coated abrasive cloth, as shown, includes the following steps: S1. Substrate Pretreatment: Using civilian clothing fiber fabric as the substrate, the following treatments are performed sequentially: S101, directional degreasing: In a 5%-6% sodium hydroxide solution, treat at 60-65℃ for 25-35 minutes with a bath ratio of 1:20. After degreasing, wash with water until the pH is 6.5-7.5. After drying, control the moisture content of the substrate to 6%-8%. S102, Twin-roll calendering: A combination of galvanized hard rollers and nitrile rubber elastic rollers is used to calender the fabric at 80-85℃ and 6-7MPa pressure, with a conveying speed of 2.5-3m / min. S103, Plasma Modification: For fine abrasive substrates of 200 mesh and above, treat with 350-450W power for 3-5 seconds in an atmosphere of argon to oxygen volume ratio of 9:1. S2. Primer Coating: Mix E-44 epoxy resin and 2123 phenolic resin at a mass ratio of 1:1, add 3%-5% xylene diluent (by mass of total resin) to adjust the viscosity to 2000-2500 mPas, and apply to the pretreated substrate surface using a doctor blade and roller coating process. Then pre-bake at 100-105℃ for 6-8 minutes to allow the primer to cure to 40%-50%. S3, Electrostatic Abrasive Coating: Selective abrasive coating for different particle size ranges. For 40-200 mesh coarse abrasives, under conditions of 30-35kV voltage and substrate tension of 60-70N / m, the abrasive planting time is 13-15s, and the abrasive planting density is 75 particles / cm³. 2 Embedding depth 50%; For fine abrasives of 200-5000 mesh, under conditions of 45-50kV voltage and substrate tension of 50-60N / m, sand planting for 8-10 seconds is performed, with a sand planting density of 120 grains / cm³. 2 Embedding depth 30%; S4. Topcoat Coating and Curing: Topcoat is applied to the substrate after sand planting. The topcoat is made by adding 1%-2% of the total mass of the topcoat to the base coat formula. Nano-alumina is dried at 120℃ for 2 hours and ultrasonically dispersed for 10 minutes. The coating thickness is controlled by a micro-gravity roller coating process. Then, it is cured at 125-130℃ for 25-30 minutes to achieve an overall curing degree of 90% for the abrasive layer. S5. Preparation and curing of multifunctional coating: Prepare a coating slurry containing acrylic resin, 5%-8% nano-silica, 10%-12% magnesium hydroxide and 1%-2% polytetrafluoroethylene micro powder by weight of the coating, and apply it to the topcoat layer using a high-pressure airless spraying process with a spraying pressure of 0.8-1.0 MPa. Then, perform a three-stage curing process: leveling at 120℃ for 5 min, curing at 150-160℃ for 15-20 min, and forced air cooling. S6. Finished product post-processing: The physical and functional properties of the cured sandpaper are tested. After passing the test, it is cut into specifications and packaged with moisture-proof materials.

[0020] Preferably, the civilian clothing fiber fabric in S1 is a 100% polyester plain weave fabric that has undergone degreasing and calendering pretreatment. The yarn specifications of the polyester plain weave fabric are 75D / 36F FDY150D / 96F DTY, with a warp density of 552 threads / inch, a weft density of 452 threads / inch, and a weight of 95-105 g / m.

[0021] Preferably, the electrode spacing for plasma treatment in S103 is 5-8 mm.

[0022] Preferably, the scraper gap is 0.10-0.12 mm when coarse abrasive is coated in S2, and the scraper gap is 0.07-0.09 mm when fine abrasive is coated.

[0023] Preferably, the coarse abrasive in S3 is brown corundum, and the fine abrasive is ceramic abrasive; before abrasive is applied, the abrasives need to be dried at 105-110℃ for 12-15 minutes to reduce the moisture content to 0.3%.

[0024] Preferably, in S4, the depth of the micro-concave roller cavity is 30-40 μm when applying coarse abrasive adhesive and 20-30 μm when applying fine abrasive adhesive.

[0025] Preferably, the solid content of the acrylic resin in S5 is 45%-50%, and the glass transition temperature is 50-60℃.

[0026] Preferably, the coating slurry in S5 also contains a nano-silver antibacterial agent with a particle size of 20-50nm, accounting for 1%-2% of the total mass of the coating.

[0027] Preferably, the resin system used in S2 and S4 is a water-based epoxy-acrylic composite resin system, and a solvent recovery device is provided in the coating and curing section.

[0028] Preferably, sensors are installed at key workstations S1-S5 to collect process parameters in real time through the PLC system and compare and adaptively adjust them with the preset process model.

[0029] Example 1: Preparation of an ultra-soft coated abrasive cloth This embodiment provides a method for preparing ultra-soft coated abrasive cloth, which strictly follows the core steps and parameter ranges defined in claim 1.

[0030] S1. Substrate pretreatment: S101. Targeted Degreasing: 100% polyester plain weave fabric (yarn specifications: 75D / 36FFDY150D / 96F DTY) with a weight of about 100g / m was selected as the base material. A 5.5% sodium hydroxide aqueous solution was prepared with a bath ratio of 1:20. The fabric was immersed in the alkaline solution and treated at 63℃ for 30min. During the treatment, the amount of wax residue was monitored by high performance liquid chromatography (HPLC). The reaction was terminated when the wax content was lower than 0.5%. Subsequently, the fabric was washed in stages with deionized water at 45℃ using countercurrent water for a total of 4 times, 5min each time. Finally, the pH value of the fabric was neutralized to about 7.0. S102, Twin-roll calendering: The washed fabric is dried with hot air (temperature 83℃, wind speed 1.8m / s) to control the moisture content to about 7%. The dried fabric is then fed into a calendering unit consisting of a galvanized hard roll (Ra0.02m) and a nitrile rubber elastic roll (Shore hardness 85 HA). The roll temperature is set to 82℃, the rolling pressure to 6.5 MPa, and the fabric conveying speed to 2.8 m / min. After calendering, the substrate surface is smooth and flat, without obvious wrinkles. S103, Plasma Surface Modification: In this embodiment, 200-5000 mesh fine abrasive is used. Therefore, the calendered substrate is subjected to plasma treatment. A mixture of argon and oxygen (volume ratio 9:1) is used as the treatment atmosphere. The plasma generator power is set to 400W and the treatment electrode distance (distance between the substrate and the electrode) is 6mm. The substrate surface is scanned for 4 seconds. After treatment, the hydrophilicity of the substrate surface is significantly improved. S2, Base Coating: Preparation of the primer: Weigh E-44 epoxy resin and 2123 phenolic resin at a mass ratio of 1:1, mix them, and add xylene diluent accounting for 4% of the total resin mass. Stir at 900 r / min for 30 min at 25℃, and the viscosity is measured to be 2200 mPas. Using a doctor blade roller coating equipment, adjust the doctor blade gap to 0.08 mm according to the plan to implant fine abrasive later, and evenly coat the primer on the pretreated substrate. Then, immediately send the coated substrate into a 105℃ hot air circulating oven with a wind speed of 2.2 m / s for 7 min to pre-bake, so that the primer reaches partial curing (curing degree of about 45%). At this time, the adhesive surface is slightly sticky but not sticky to the touch. S3, Electrostatic Sand Planting: Abrasive preparation: Select 3000-mesh ceramic micro powder as fine abrasive, place it in a hot air drying oven at 108℃ for 13 minutes to ensure that the moisture content is less than 0.3%, and then use an ultrasonic vibrating screen to sieve it to remove agglomerates and impurities. Sand planting operation: The substrate coated with primer is passed flat through the electrostatic sand planting area with a tension of 55 N / m. The high-voltage electrostatic generator is turned on and the voltage is increased to 48 kV. The substrate is sand planted for 9 seconds. During the sand planting process, the abrasive is vertically and uniformly implanted into the incompletely cured primer layer under the action of strong electric field, forming a high-density abrasive layer. The abrasive is uniformly distributed and there is no agglomeration when observed by volume microscopy. S4. Topcoat application and curing: Topcoat formulation: Based on the base coat formulation, an additional 1.5% by weight of nano-alumina (50nm particle size) was added to the topcoat. This nano-alumina had been pre-dried at 120℃ for 2 hours and ultrasonically dispersed for 10 minutes. Using a micro-grooving roller coating device with a cell depth of 25m, the topcoat was evenly applied to the sand-coated surface, controlling the wet film thickness. Subsequently, the sand was placed in a curing oven at 128℃ and cured for 28 minutes. Differential scanning calorimetry (DSC) determined that the overall curing degree of the abrasive layer reached over 92% after curing. S5. Preparation and curing of multifunctional coatings: S501, Coating Slurry Preparation: First, divide the acrylic resin with a solid content of 48% and a glass transition temperature of 55℃ into two parts. Take one part (accounting for 50% of the total acrylic resin) and mix it with nano-silica (particle size 25nm) accounting for 6% of the total coating mass. Disperse it using 500W ultrasonic for 20min. Then, add magnesium hydroxide accounting for 11% of the total coating mass and polytetrafluoroethylene micro powder accounting for 1.5% of the total coating mass. Stir at high speed of 1500r / min for 40min using a paddle mixer. Finally, add the remaining acrylic resin and stir at 800r / min for 15min to obtain a uniform and stable coating slurry with a viscosity of 1100mPas at 25℃. S502. Spraying and Curing: High-pressure airless spraying equipment is used, with a 0.4mm nozzle. Under a spraying pressure of 0.9MPa, the coating slurry is evenly sprayed onto the surface of the abrasive cloth at a distance of 19cm. The spraying amount is synchronized with the substrate conveying speed (2.8m / min). Then, a three-stage curing process is performed: first, leveling is carried out at 120℃ for 5min; then, forced curing is carried out at 155℃ for 18min; finally, the abrasive cloth is rapidly cooled to room temperature by forced air cooling (wind speed 3.5m / s). S6. Finished product post-processing: The cured abrasive cloth is sampled and tested according to standards such as GB / T3923.1 and GB / T2408, including tensile strength, abrasive shedding rate, flame retardancy rating, and high temperature resistance. After passing the test, the wide abrasive cloth is cut into rolls of 1 meter wide and 20 meters long using a CNC slitting machine. The rolls are then wrapped in 0.08mm thick PE moisture-proof film, packed into five-layer corrugated cardboard boxes, and contain montmorillonite desiccant to complete the packaging.

[0031] Example 2: Ultra-soft coated abrasive cloth with antibacterial function This embodiment, based on Embodiment 1, further embodies the additional features of claim 8, namely, endowing the product with antibacterial function, specifically: In the S5 stage of slurry preparation for multifunctional coating preparation and curing, in addition to adding magnesium hydroxide and polytetrafluoroethylene micro powder, an additional 1.2% of the total coating mass and a particle size of 30nm nano-silver antibacterial agent was added. This antibacterial agent was pre-modified to improve its dispersibility in the resin. The remaining preparation steps and parameters were exactly the same as in Example 1. The resulting product, while maintaining all the properties of Example 1, showed excellent antibacterial effect after antibacterial testing (such as JIS Z 2801).

[0032] Example 3: Using a water-based system and sand-coated abrasive cloth This embodiment comprehensively demonstrates the sand-planting characteristics of claims 9 and 1, showcasing an environmentally friendly production process. Specifically: (1) In S2, primer coating and S4, topcoat coating and curing, the resin system is replaced with a water-based epoxy-acrylic composite emulsion with equivalent solid content. Deionized water is used as a diluent during preparation, and the stirring process is adjusted accordingly to adapt to the characteristics of the water-based system. An activated carbon adsorption + condensation recovery device is connected to the coating and drying parts to treat the small amount of water vapor and possible volatile organic matter that escapes from the oven. (2) In S3, electrostatic sand planting, selective sand planting is performed on abrasives of different particle size ranges purchased by the user: For 40-200 mesh abrasives, under conditions of 30-35kV voltage and substrate tension of 60-70N / m, the abrasive planting time is 13-15s, and the abrasive planting density is 75 particles / cm³. 2 Embedding depth 50%; For abrasives of 200-5000 mesh, under conditions of 45-50kV voltage and substrate tension of 50-60N / m, sand planting should be carried out for 8-10 seconds, with a sand planting density of 120 grains / cm³. 2 Embedding depth 30%.

[0033] Comparative example: Traditional sandpaper To verify the effectiveness of the present invention, a commercially available ordinary sandpaper with industrial fabric as the base material and phenolic resin as the binder was selected as a comparative example.

[0034] Performance comparison: Key performance tests were conducted on the products obtained in Examples 1-3 and the comparative product, and the results are shown in the table below: Test Project Example 1 Example 2 Example 3 Comparative Example feel and fit Extremely soft and easily conforms to curved surfaces Extremely soft and easily conforms to curved surfaces Extremely soft and easily conforms to curved surfaces It has a relatively hard texture and limited ability to conform to curved surfaces. Abrasive layer adhesion Abrasive shedding rate is extremely low. Abrasive shedding rate is extremely low. Abrasive shedding rate is extremely low. The abrasive shedding rate is extremely low and relatively high. High temperature resistance (200℃, 24h) The coating is intact, with no chalking or cracking. The coating is intact, with no chalking or cracking. The coating is intact, with no chalking or cracking. The coating is visibly charred and brittle. Flame retardant rating (GB / T2408) V-0 level V-0 level V-0 level Not reached Level V-0 Anti-clogging Excellent performance; grinding debris is easily detached. Excellent performance; grinding debris is easily detached. Excellent performance; grinding debris is easily detached. Generally, it is easy to accumulate debris. Antibacterial properties (JIS Z 2801) No antibacterial agents added, not tested. >99% (anti-Staphylococcus aureus) No antibacterial agents added, not tested. No antibacterial agents added, not tested. This invention selects civilian clothing fiber fabric as a cross-border substrate and overcomes the defect that its original characteristics are not suitable for industrial grinding through a series of targeted pretreatment processes, thus providing a new material basis for the development of high-performance composite abrasive cloth. The test results show that the ultra-soft coated abrasive cloth prepared by the method of this invention, while maintaining ultra-softness, surpasses traditional abrasive cloth in terms of comprehensive performance such as abrasive bonding strength, high temperature resistance, flame retardancy, and anti-clogging. Examples 2 and 3 further show that this invention has good functional scalability and environmentally friendly production potential.

[0035] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. 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 method of making an ultra-soft coated abrasive, comprising: The method comprises the following steps: S1, substrate pretreatment: select a civilian clothing fiber base cloth as a substrate, and sequentially perform the following treatments: S101, directional degreasing: in a 5%-6% sodium hydroxide solution, treat at 60-65°C for 25-35 min, bath ratio 1:20, after degreasing, wash to pH 6.5-7.5, and dry the substrate to control the moisture content at 6%-8%; S102, double roller calendering: adopt a combination of galvanized hard roller and nitrile rubber elastic roller, and calender the base cloth at 80-85°C and 6-7 MPa pressure, and the conveying speed is 2.5-3 m / min; S103, plasma modification: for a fine abrasive substrate of 200 mesh and above, treat in an atmosphere of argon and oxygen with a volume ratio of 9:1 at a power of 350-450 W for 3-5 s; S2, primer coating: mix E-44 type epoxy resin and 2123 type phenolic resin at a mass ratio of 1:1, add 3%-5% xylene diluent based on the total mass of the resin, adjust the viscosity to 2000-2500 mPas, and coat on the pretreated substrate surface by using a doctor blade roll coating process, then pre-dry at 100-105°C for 6-8 min to make the primer curing degree reach 40%-50%; S3, electrostatic sanding: selectively sand different particle size ranges of abrasives: For 40-200 mesh coarse abrasive, sanding for 13-15 s at 30-35 kV voltage, substrate tension 60-70 N / m, sanding density 75 grains / cm 2 , embedding depth 50% For 200-5000 mesh fine abrasive, sanding for 8-10 s at 45-50 kV voltage, substrate tension 50-60 N / m, sanding density 120 particles / cm 2 , embedding depth 30% S4, topcoat coating and curing: coat the topcoat on the substrate after sanding, the topcoat is based on the primer formula and adds 1%-2% nano alumina based on the total mass of the topcoat, which is dried at 120°C for 2 h and ultrasonically dispersed for 10 min, and the coating thickness is controlled by using a micro concave roller coating process, then cure at 125-130°C for 25-30 min to make the overall curing degree of the abrasive layer reach 90%; S5, multifunctional coating preparation and curing: prepare a coating slurry containing acrylic resin, 5%-8% nano silicon dioxide, 10%-12% magnesium hydroxide and 1%-2% polytetrafluoroethylene powder based on the total mass of the coating, and coat on the topcoat layer by using a high-pressure airless spraying process with a spraying pressure of 0.8-1.0 MPa, then sequentially perform three-stage curing of 120°C leveling for 5 min, 150-160°C curing for 15-20 min, and forced air cooling; S6, finished product post-treatment: detect the physical and functional properties of the cured abrasive cloth, cut according to the specifications after passing the test, and package with moisture-proof materials.

2. The method of claim 1, wherein: The base cloth in S1 is a 100% polyester plain cloth after degreasing and calendering pretreatment, and the yarn specification of the polyester plain cloth is 75D / 36F FDY 150D / 96F DTY, the warp density is 552 ends / inch, the weft density is 452 ends / inch, and the grammage is 95-105 g / m.

3. The method of claim 1, wherein: The electrode distance of the plasma treatment in S103 is 5-8 mm.

4. The method of claim 1, wherein: The doctor blade gap is 0.10-0.12 mm when coating coarse abrasives, and the doctor blade gap is 0.07-0.09 mm when coating fine abrasives.

5. The method of claim 1, wherein: The coarse abrasive in the S3 is brown corundum, and the fine abrasive is ceramic abrasive; before sanding, the abrasives are dried at 105-110 DEG C for 12-15 min, so that the moisture content is 0.3%.

6. The method of claim 1, wherein: The micro-concave roller screen hole depth for coating the coarse abrasive surface glue in the S4 is 30-40 m, and the screen hole depth for coating the fine abrasive surface glue is 20-30 m.

7. The method of claim 1, wherein: The solid content of the acrylic resin in the S5 is 45%-50%, and the glass transition temperature is 50-60 DEG C.

8. The method of claim 1, wherein: The coating slurry in the S5 further adds 1%-2% of nano-silver antibacterial agent with a particle size of 20-50 nm based on the total mass of the coating.

9. The method of claim 1, wherein: The resin system used in the S2 and S4 is a water-based epoxy-acrylic composite resin system, and a solvent recovery device is equipped in the coating and curing section.

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