Buffer damping cloth with bottom buffer protective layer for polishing and its preparation process

Abstract

This invention discloses a cushioning damping cloth with a bottom buffer protective layer for polishing and its preparation process, belonging to the technical field of damping cloth. The cushioning damping cloth with a bottom buffer protective layer for polishing of this invention includes a base buffer layer, a hot melt adhesive layer, and a polishing surface layer. The base buffer layer is bonded to the polishing surface layer by the hot melt adhesive layer. The base buffer layer includes a first elastic layer, a second elastic layer, a first fabric layer, a second fabric layer, and a third fabric layer. This invention solves the problem of large differences in elasticity among existing polyurethane porous adsorption pads of different elastic pads. The cushioning damping cloth with a bottom buffer protective layer for polishing proposed in this invention uses palm fiber monofilaments twisted into a spiral rope to obtain crimped palm fibers, which are then mixed and bonded with natural rubber. The bonded fiber web forms elastic nodes at the fiber intersections, improving the elasticity of the palm fibers and enhancing the compressive and tensile strength of the base buffer layer, thereby playing a cushioning and protective role.

Description

Technical Field

[0001] This invention relates to the field of damping cloth technology, specifically to a cushioning damping cloth with a bottom buffer protective layer for polishing and its preparation process. Background Technology

[0002] Damping cloth is a velvety polishing material with a fine texture, soft surface, porous structure, elasticity, and long service life. During polishing, it effectively absorbs polishing fluid, increasing cutting force while preventing scratches on the workpiece. Damping cloth is suitable for the final polishing of optical components, crystals, and metals and glass materials. It can also be used to polish special materials such as silicon, germanium, zinc selenide, gallium arsenide, alloy steel, ceramics, and acrylic glass.

[0003] Chinese Patent CN114683183B discloses a damping cloth for polishing precious metal surfaces and its manufacturing process. The damping cloth comprises, from the polishing contact surface to the adsorption surface, a grinding aid coating layer, a water-repellent base pad, and an elastic pad. The grinding aid coating layer uses hydrophilically modified polyvinylidene fluoride and polyethylene glycol as film-forming materials. The good hydrophilicity of the grinding aid coating layer allows the polishing liquid to be evenly dispersed. Polyethylene glycol is water-soluble. During the polishing process, the grinding aid coating layer slowly erodes, and the abrasive is evenly released to participate in the polishing, which can reduce the concentration of the polishing liquid and make the abrasive particles in the polishing liquid easier to disperse, thereby improving the polishing accuracy.

[0004] While this patent has to some extent solved the problem in the prior art that the micro powder under polishing cutting is easily stuck in the gaps and difficult to separate from the polishing pad, resulting in a large polishing loss rate of precious metals, the elastic pad in this patent is a polyurethane porous adsorption pad, and different elastic pads of polyurethane porous adsorption pads have large differences in elasticity. Summary of the Invention

[0005] The purpose of this invention is to provide a cushioning damping cloth with a bottom buffer protective layer for polishing and its preparation process. The palm fiber acts as the bottom buffer. After the palm fiber is treated with alkali, the interior of the palm fiber has a porous structure caused by the decomposition of lignin by alkali. After the esterified palm fiber is cooled, methyl palmitate becomes solid, and the antistatic agent and graphene are fixed on the surface of the palm fiber, which improves the antistatic, wear-resistant and heat-resistant properties of the palm fiber and solves the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a cushioning damping cloth for polishing with a bottom buffer protective layer, comprising a base buffer layer, a hot melt adhesive layer, and a polishing surface layer. The base buffer layer is bonded to the polishing surface layer by the hot melt adhesive layer. The base buffer layer comprises a first elastic layer, a second elastic layer, a first fabric layer, a second fabric layer, and a third fabric layer. A first elastic layer is sandwiched between the first fabric layer and the second fabric layer, and a second elastic layer is sandwiched between the second fabric layer and the third fabric layer. The first elastic layer is made of the following raw materials in parts by weight: 20-45 parts esterified palm fiber, 10-25 parts natural rubber, and 5-8 parts modifier. The second elastic layer is made of the following raw materials in parts by weight: 20-45 parts esterified palm fiber, 15-20 parts pig bristles, 10-25 parts natural rubber, and 5-8 parts modifier.

[0007] Preferably, the first fabric layer is woven from nylon fibers, the second fabric layer is woven from aramid fibers, and the third fabric layer is woven from polyester fibers.

[0008] Preferably, the modifier includes an antistatic agent and graphene, with the mass ratio of the antistatic agent to graphene being 1:2.

[0009] Preferably, the preparation process of the esterified palm fiber is as follows:

[0010] The palm leaf sheath fiber sheets are alkali washed to obtain alkali-treated palm fibers, which are then broken down and combed into palm fiber monofilaments.

[0011] Palm fiber monofilaments are twisted into spiral ropes using a rope-making machine. After being set at high temperature, the spiral ropes are removed and broken down to obtain curled palm fibers.

[0012] Alkali-washed palm fibers, methanol, and concentrated sulfuric acid are mixed and subjected to esterification to obtain esterified palm fibers.

[0013] Preferably, the ambient temperature for twisting the palm fiber monofilaments into a spiral rope is 120-140℃, and the holding time is 5-7 minutes.

[0014] Preferably, the polished surface layer is made of the following raw materials in parts by weight: 38-45 parts polyurethane, 25-36 parts epoxy resin, 2-6 parts dispersant, and 10-13 parts abrasive component.

[0015] Preferably, the abrasive composition comprises the following raw materials: 23-50% silicon carbide, 15-25% alumina, 5-10% chromium oxide, 12-18% titanium dioxide, 15-18% oxide ceramics, and 2-10% pig bristles.

[0016] Another technical problem to be solved by the present invention is to provide a process for preparing a cushioning damping cloth with a bottom buffer protective layer for polishing, comprising the following steps:

[0017] S1 is used to prepare the substrate buffer layer:

[0018] S11: The obtained esterified palm fiber is mixed with a modifier and cooled to obtain modified palm fiber. The modified palm fiber is blown by airflow into a three-dimensional uniform distribution state, so that the palm fiber overlaps with each other to form a network.

[0019] S12: Two layers of mesh palm fibers are stacked and mixed with natural rubber and bonded together. The bonded fiber mesh forms elastic nodes at the intersection of the fibers to form the first elastic layer.

[0020] S13: Cut the pig bristles to the height of two layers of mesh palm fibers, stack three layers of mesh palm fibers, and evenly insert the pig bristles vertically into the three layers of mesh palm fibers. Then mix and bond natural rubber with them to form the second elastic layer.

[0021] S14: Apply a layer of polyurethane adhesive to both sides of the first elastic layer and the second elastic layer, and lay them in the order of the third fabric layer, the second elastic layer, the second fabric layer, the first elastic layer and the first fabric layer from bottom to top. After laying them neatly, apply pressure until the polyurethane adhesive dries to form a base buffer layer.

[0022] S2 is used to prepare the polished surface layer:

[0023] S21: Add polyurethane and epoxy resin into the mixer, and mix the raw materials thoroughly by the high-speed rotating stirring blades to make them evenly mixed. Then add dispersant into the mixer to make the raw materials evenly dispersed. After the raw materials react and fuse, put the raw materials into the extruder, and extrude the raw materials into sheets by the rotating extrusion rollers to make polished surface layer semi-finished products.

[0024] S22: Silicon carbide, alumina, chromium oxide, titanium dioxide, oxide ceramics and pig bristles are mixed in proportion and then ground thoroughly to obtain an abrasive composition;

[0025] S23: The abrasive components are implanted onto the semi-finished polishing surface layer using the electrostatic sand-planting method to form the polishing surface layer;

[0026] S3 Preparation of Finished Product: Apply a hot melt adhesive layer to the side of the polished surface without abrasive components, and stack the base buffer layer and the hot melt adhesive layer together. Place them in a hot press, preheat first, and then hot press. After hot pressing, cool to room temperature and cut to obtain the finished buffer damping cloth.

[0027] Preferably, the pressure applied after coating the polyurethane adhesive in step S14 is 0.1-0.3 MPa, and the pressure application time is 30-60 seconds.

[0028] Preferably, in step S3, the hot-pressing temperature is 70-90℃, the hot-pressing time is 30-60s, and the hot-pressing pressure is 0.7-0.8Mpa.

[0029] Compared with the prior art, the beneficial effects of the present invention are:

[0030] 1. This invention utilizes palm fiber as a bottom buffer. After alkaline washing, the palm fiber has a porous structure due to the decomposition of lignin by alkali. After cooling, methyl palmitate becomes solid, fixing the antistatic agent and graphene on the surface of the palm fiber, thereby improving the antistatic, wear-resistant and heat-resistant properties of the palm fiber.

[0031] 2. This invention obtains coiled palm fibers by twisting palm fiber monofilaments into a spiral rope, and then bonding them with natural rubber. The bonded fiber web forms elastic nodes at the fiber intersections, which improves the elasticity of the palm fibers and enhances the compressive and tensile strength of the base buffer layer, thereby playing a buffering and protective role.

[0032] 3. The present invention utilizes the porous structure of palm fibers, and the multi-layer palm fiber network structure of the first and second elastic layers, to give the base buffer layer good water retention capacity. During the polishing process, it absorbs the polishing liquid and uses the liquid to play a buffering and protective role.

[0033] 4. This invention improves the compressive strength of the second elastic layer by inserting pig bristle material into the palm fiber mesh, which provides a certain support force to the thicker second elastic layer. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the buffer damping cloth structure of the present invention;

[0035] Figure 2 This is a schematic diagram of the base buffer layer structure of the present invention.

[0036] In the figure: 1. Base buffer layer; 11. First elastic layer; 12. Second elastic layer; 13. First fabric layer; 14. Second fabric layer; 15. Third fabric layer; 2. Hot melt adhesive layer; 3. Polished surface layer. Detailed Implementation

[0037] 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.

[0038] Example 1:

[0039] To resolve the existing issues, please refer to Figures 1-2This embodiment provides the following technical solution:

[0040] A cushioning damping cloth with a bottom buffer protective layer for polishing includes a base buffer layer 1, a hot melt adhesive layer 2, and a polishing surface layer 3. The base buffer layer 1 is bonded to the polishing surface layer 3 via the hot melt adhesive layer 2. The base buffer layer 1 includes a first elastic layer 11, a second elastic layer 12, a first fabric layer 13, a second fabric layer 14, and a third fabric layer 15. The first elastic layer 11 is sandwiched between the first fabric layer 13 and the second fabric layer 14, and the second elastic layer 12 is sandwiched between the second fabric layer 14 and the third fabric layer 15.

[0041] The first elastic layer 11 is made of the following raw materials in parts by weight: 20 parts esterified palm fiber, 10 parts natural rubber, and 5 parts modifier;

[0042] The second elastic layer 12 is made of the following raw materials in parts by weight: 20 parts esterified palm fiber, 15 parts pig bristles, 10 parts natural rubber, and 5 parts modifier.

[0043] The first fabric layer 13 is woven from nylon fibers, the second fabric layer 14 is woven from aramid fibers, and the third fabric layer 15 is woven from polyester fibers.

[0044] The base buffer layer 1 is made of nylon fiber, aramid fiber and polyester fiber stacked together to increase the toughness and wrinkle resistance of the base buffer layer 1 and improve the tensile strength of the base buffer layer 1.

[0045] The modifier includes an antistatic agent and graphene, with a mass ratio of 1:2. By adding the antistatic agent and graphene and filling them into the gaps in the palm fibers, the antistatic properties of the palm fibers can be improved, as well as their wear resistance and heat resistance.

[0046] The preparation process of esterified palm fiber is as follows:

[0047] The palm leaf sheath fiber sheets are alkali washed to obtain alkali-treated palm fibers, which are then broken down and combed into palm fiber monofilaments.

[0048] Palm fiber monofilaments are twisted into spiral ropes using a rope-making machine. After high-temperature setting, the ropes are removed and kept at an ambient temperature of 140°C for 5 minutes to decompose the spiral ropes and obtain curled palm fibers.

[0049] Alkali-washed palm fibers, methanol, and concentrated sulfuric acid are mixed and subjected to esterification to obtain esterified palm fibers.

[0050] The polished surface layer 3 is made of the following raw materials in parts by weight: 40 parts polyurethane, 30 parts epoxy resin, 3 parts dispersant, and 10 parts abrasive components.

[0051] The abrasive composition includes the following raw materials: 37% silicon carbide, 23% alumina, 8% chromium oxide, 12% titanium dioxide, 16% oxide ceramics, and 4% pig bristles.

[0052] To better illustrate the preparation process of a polishing damping cloth with a bottom buffer protective layer, this embodiment presents a preparation process for such a cloth, including the following steps:

[0053] S1 Preparation of base buffer layer 1:

[0054] S11: The obtained esterified palm fiber is mixed with a modifier and cooled to obtain modified palm fiber. The modified palm fiber is blown by airflow into a three-dimensional uniform distribution state, so that the palm fiber overlaps with each other to form a network.

[0055] S12: Two layers of mesh palm fiber are stacked and mixed with natural rubber and bonded together. The bonded fiber mesh forms elastic nodes at the intersection of the fibers to form the first elastic layer 11.

[0056] S13: Cut the pig bristles to the height of two layers of mesh palm fibers, stack three layers of mesh palm fibers, and evenly insert the pig bristles vertically into the three layers of mesh palm fibers. Then mix and bond natural rubber with them to form the second elastic layer 12.

[0057] S14: Apply a layer of polyurethane adhesive to both sides of the first elastic layer 11 and the second elastic layer 12, and lay them in the order of the third fabric layer 15, the second elastic layer 12, the second fabric layer 14, the first elastic layer 11 and the first fabric layer 13 from bottom to top. After laying them neatly, apply pressure until the polyurethane adhesive dries. The pressure is 0.2 MPa and the pressure application time is 45 seconds to form the base buffer layer 1.

[0058] S2 prepares polished surface layer 3:

[0059] S21: Add polyurethane and epoxy resin into the mixer, and mix the raw materials thoroughly by the high-speed rotating stirring blades to make them evenly mixed. Then add dispersant into the mixer to make the raw materials evenly dispersed. After the raw materials react and fuse, put the raw materials into the extruder and extrude them into sheets by the rotating extrusion rollers to make polished surface layer 3 semi-finished product.

[0060] S22: Silicon carbide, alumina, chromium oxide, titanium dioxide, oxide ceramics and pig bristles are mixed in proportion and then ground thoroughly to obtain an abrasive composition;

[0061] S23: The abrasive components are implanted onto the semi-finished polishing surface layer 3 using the electrostatic sand-planting method to form polishing surface layer 3;

[0062] S3 Preparation of finished product: Apply hot melt adhesive layer 2 to the side of polished surface layer 3 without abrasive components, and stack the base buffer layer 1 and hot melt adhesive layer 2 together in a hot press. First, preheat, and then hot press. The hot pressing temperature is 70℃, the hot pressing time is 45s, and the hot pressing pressure is 0.7Mpa. After hot pressing, cool to room temperature and cut to obtain the finished buffer damping cloth.

[0063] Example 2:

[0064] This embodiment uses the same preparation method as Example 1, and the raw materials for each layer are as follows:

[0065] The first elastic layer 11 is made of the following raw materials in parts by weight: 30 parts esterified palm fiber, 10 parts natural rubber, and 5 parts modifier;

[0066] The second elastic layer 12 is made of the following raw materials in parts by weight: 30 parts esterified palm fiber, 15 parts pig bristles, 10 parts natural rubber, and 5 parts modifier.

[0067] The other materials are the same as in Example 1. In this example, the amount of esterified palm fiber in the first elastic layer 11 and the second elastic layer 12 is increased.

[0068] Example 3:

[0069] This embodiment uses the same preparation method as Example 1, and the raw materials for each layer are as follows:

[0070] The first elastic layer 11 is made of the following raw materials in parts by weight: 45 parts esterified palm fiber, 10 parts natural rubber, and 5 parts modifier;

[0071] The second elastic layer 12 is made of the following raw materials in parts by weight: 45 parts esterified palm fiber, 15 parts pig bristles, 10 parts natural rubber, and 5 parts modifier.

[0072] Other materials are the same as in Example 1. In this example, the amount of esterified palm fiber in the first elastic layer 11 and the second elastic layer 12 is increased based on Example 2.

[0073] Example 4:

[0074] This embodiment uses the same preparation method as Example 1, and the raw materials for each layer are as follows:

[0075] The first elastic layer 11 is made of the following raw materials in parts by weight: 30 parts esterified palm fiber, 15 parts natural rubber, and 5 parts modifier;

[0076] The second elastic layer 12 is made of the following raw materials in parts by weight: 30 parts esterified palm fiber, 15 parts pig bristles, 15 parts natural rubber, and 5 parts modifier.

[0077] The other materials are the same as in Example 1. In this example, the amount of natural rubber in the first elastic layer 11 and the second elastic layer 12 is increased based on Example 2.

[0078] Example 5:

[0079] This embodiment uses the same preparation method as Example 1, and the raw materials for each layer are as follows:

[0080] The first elastic layer 11 is made of the following raw materials in parts by weight: 30 parts esterified palm fiber, 15 parts natural rubber, and 5 parts modifier;

[0081] The second elastic layer 12 is made of the following raw materials in parts by weight: 30 parts esterified palm fiber, 20 parts pig bristles, 15 parts natural rubber, and 5 parts modifier.

[0082] Other materials are the same as in Example 1. In this example, the amount of pig bristles in the second elastic layer 12 is increased based on Example 4.

[0083] Comparative Example 1:

[0084] In this comparative example, the first elastic layer 11 is not provided, and the other structures and materials are the same as in Example 1. The step of preparing the first elastic layer 11 in Example 1 is removed to prepare the buffer damping cloth in the comparative example.

[0085] Comparative Example 2:

[0086] This embodiment uses the same preparation method as Example 1, and the raw materials for each layer are as follows:

[0087] The first elastic layer 11 is made of the following raw materials in parts by weight: 30 parts esterified palm fiber, 15 parts natural rubber, and 5 parts modifier;

[0088] The second elastic layer 12 is made of the following raw materials in parts by weight: 30 parts esterified palm fiber, 15 parts natural rubber, and 5 parts modifier.

[0089] The other materials are the same as in Example 1. In this example, the pig bristle component in the second elastic layer 12 is removed.

[0090] The component comparisons of the above-described embodiments and comparative examples are shown in Table 1 below.

[0091] Table 1: Comparison of the composition of various embodiments and comparative examples

[0092]

[0093] The prepared buffer damping pads were tested, and the following data were obtained, as shown in Table 2:

[0094] Table 2: Performance test results of various embodiments and comparative examples

[0095]

[0096]

[0097] Table 2 shows that the buffer damping fabrics prepared in Examples 1 to 5 all have high compressibility and tensile strength. Among them, the buffer damping fabrics prepared in Examples 4 and 5 have the best compressibility and tensile strength. In Comparative Example 1, the lack of the first elastic layer 11 resulted in a significant decrease in both compression and tensile strength. In Comparative Example 2, the lack of pig bristle components in the second elastic layer 12 increased the compression ratio, but significantly reduced the compression rebound rate. This indicates that vertically arranged pig bristle material can improve the compression performance of the buffer damping fabric.

[0098] In summary, the polishing damping cloth with a bottom buffer protective layer proposed in this invention uses palm fiber as the bottom buffer. After alkaline washing, the palm fiber has a porous structure due to the decomposition of lignin by the alkali. After esterification, methyl palmitate becomes solid upon cooling, fixing the antistatic agent and graphene to the surface of the palm fiber, thus improving the antistatic, wear-resistant, and heat-resistant properties of the palm fiber. The palm fiber monofilaments are twisted into a spiral rope to obtain a crimped palm fiber, which is then mixed and bonded with natural rubber. The bonded fiber web forms elastic nodes at the fiber intersections, improving the elasticity of the palm fiber and enhancing the compressive and tensile strength of the base buffer layer 1, thereby playing a buffering and protective role. The palm fiber itself has a porous structure, and the first elastic layer 11 and the second elastic layer 12 have a multi-layer palm fiber web structure, giving the base buffer layer 1 good water retention capacity. During the polishing process, it absorbs the polishing liquid and uses the liquid to play a buffering and protective role.

[0099] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0100] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A cushioning damping cloth for polishing with a bottom cushioning protective layer, comprising a base cushioning layer (1), a hot melt adhesive layer (2), and a polishing surface layer (3), characterized in that: The base buffer layer (1) is bonded to the polished surface layer (3) through a hot melt adhesive layer (2). The base buffer layer (1) includes a first elastic layer (11), a second elastic layer (12), a first fabric layer (13), a second fabric layer (14), and a third fabric layer (15). The first elastic layer (11) is sandwiched between the first fabric layer (13) and the second fabric layer (14), and the second elastic layer (12) is sandwiched between the second fabric layer (14) and the third fabric layer (15). The first elastic layer (11) is made of the following raw materials in parts by weight: 20-45 parts of esterified palm fiber, 10-25 parts of natural rubber, and 5-8 parts of modifier. The second elastic layer (12) is made of the following raw materials in parts by weight: 20-45 parts of esterified palm fiber, 15-20 parts of pig bristles, 10-25 parts of natural rubber, and 5-8 parts of modifier. The modifier includes an antistatic agent and graphene, and the mass ratio of the antistatic agent to graphene is 1:

2. The preparation methods of the first elastic layer (11) and the second elastic layer (12) are as follows: S11: The obtained esterified palm fiber is mixed with a modifier and cooled to obtain modified palm fiber. The modified palm fiber is blown by airflow into a three-dimensional uniform distribution state, so that the palm fiber overlaps with each other to form a mesh; S12: The two layers of mesh palm fiber are stacked and mixed with natural rubber and bonded. The bonded fiber mesh forms elastic nodes at the fiber intersections to form the first elastic layer (11); S13: The pig bristles are cut to the height of the two layers of mesh palm fiber, three layers of mesh palm fiber are stacked, and the pig bristles are evenly inserted vertically into the mesh. In the three-layer mesh palm fiber, natural rubber is mixed and bonded to form the second elastic layer (12). The preparation process of the esterified palm fiber is as follows: the palm leaf sheath fiber sheet is alkali washed to obtain alkali-treated palm fiber, which is then broken down and combed into palm fiber monofilaments; the palm fiber monofilaments are twisted into a spiral rope using a rope making machine, and after high-temperature setting, the spiral rope is taken out and decomposed to obtain curled palm fiber; the alkali-washed palm fiber, methanol and concentrated sulfuric acid are mixed and esterified to obtain esterified palm fiber.

2. The polishing damping cloth with a bottom buffer protective layer according to claim 1, characterized in that: The first fabric layer (13) is woven from nylon fibers, the second fabric layer (14) is woven from aramid fibers, and the third fabric layer (15) is woven from polyester fibers.

3. The polishing damping cloth with a bottom buffer protective layer according to claim 2, characterized in that: The spiral rope made of palm fiber monofilaments is kept at an ambient temperature of 120-140℃ for 5-7 minutes.

4. The polishing damping cloth with a bottom buffer protective layer according to claim 3, characterized in that: The polished surface layer (3) is made of the following raw materials in parts by weight: 38-45 parts polyurethane, 25-36 parts epoxy resin, 2-6 parts dispersant, and 10-13 parts abrasive components.

5. The polishing damping cloth with a bottom buffer protective layer according to claim 4, characterized in that: The abrasive composition includes the following raw materials: 23-50% silicon carbide, 15-25% alumina, 5-10% chromium oxide, 12-18% titanium dioxide, 15-18% oxide ceramics, and 2-10% pig bristles.

6. A process for preparing a polishing damping cloth with a bottom buffer protective layer as described in claim 5, characterized in that, Includes the following steps: S1 Preparation of the base buffer layer (1): A layer of polyurethane adhesive is coated on both sides of the first elastic layer (11) and the second elastic layer (12), and laid in the order of the third fabric layer (15), the second elastic layer (12), the second fabric layer (14), the first elastic layer (11) and the first fabric layer (13) from bottom to top. After laying neatly, pressure is applied until the polyurethane adhesive dries to form the base buffer layer (1). S2 Preparation of polished surface layer (3): S21: Add polyurethane and epoxy resin into the mixer, and mix the raw materials thoroughly by the high-speed rotating stirring blades to make them uniform. Then add dispersant into the mixer to make the raw materials uniformly dispersed. After the raw materials react and fuse, put the raw materials into the extruder and extrude them into sheets by the rotating extrusion rollers to make polished surface layer (3) semi-finished product; S22: Mix silicon carbide, alumina, chromium oxide, titanium dioxide, oxide ceramics and pig bristles in proportion and grind them thoroughly to obtain abrasive components; S23: Use electrostatic sand planting method to plant the abrasive components onto the polished surface layer (3) semi-finished product to make polished surface layer (3); S3 Preparation of finished product: Apply hot melt adhesive layer (2) to the side of polished surface layer (3) without abrasive components, and stack the base buffer layer (1) and hot melt adhesive layer (2) together in a hot press. First, preheat, then hot press. After hot pressing, cool to room temperature and cut to obtain the finished buffer damping cloth.

7. The preparation process of the polishing damping cloth with a bottom buffer protective layer according to claim 6, characterized in that: The pressure applied after coating with polyurethane adhesive in step S1 is 0.1-0.3 MPa, and the pressure application time is 30-60 seconds.

8. The preparation process of the polishing damping cloth with a bottom buffer protective layer according to claim 7, characterized in that: The hot-pressing temperature in S3 is 70-90℃, the hot-pressing time is 30-60s, and the hot-pressing pressure is 0.7-0.8Mpa.

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