Grinding sheet and preparation method thereof

Abstract

The invention discloses a grinding sheet and a preparation method thereof. The grinding sheet comprises a base material; and the grinding layer is arranged on one side of the base material and comprises silicon carbide micro powder, and the side, away from the base material, of the silicon carbide micro powder is arranged in a concave-convex shape. The preparation method of the grinding sheet comprises the following steps: mixing silicon carbide micro powder, acrylic resin, isocyanate and a diluent into a mixed solution, stirring the mixed solution under the conditions of rotating speed r, ultrasonic power p and stirring time T1 to form slurry, and coating the surface of a base material with the slurry; baking the surface of the slurry at a first temperature t1 for a first baking time T2 until no viscosity exists, and rolling; and carrying out secondary baking at a second temperature t2 for a second baking time T3 to form the grinding sheet. Due to the concave-convex arrangement of the grinding sheets, the fiber height control is more stable when the ferrule is ground, and the grinding sheets are directly added with water for grinding instead of traditional grinding liquid, so that the problems of unstable fiber height control, chemical pollution and low efficiency in the traditional grinding process are solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of optical fibers, and in particular relates to a polishing sheet and a preparation method thereof. Background Art

[0002] The grinding and polishing process includes four steps: degumming, medium grinding, fine grinding, and fine polishing. In the fine grinding process, traditional technology uses polyurethane polishing flannel to achieve changes in the height of the optical fiber in the ferrule. The fiber height will also vary depending on the softness or hardness of the flannel. In this process, grinding fluid needs to be added to draw the fiber. Traditional grinding fluids include silicon carbide grinding fluid, aluminum oxide grinding fluid, cerium oxide grinding fluid, etc. The main components of the grinding fluid include abrasive particles, deionized water, and chemical additives. The abrasive particles include silicon carbide and aluminum oxide. Chemical additives include oxidants, pH regulators, surfactants, etc. The specific components of the grinding fluid vary depending on the application scenario. In the fine grinding process to achieve fiber drawing, it is very likely that the grinding fluid will remain in the ferrule holes due to improper cleaning during the grinding process, thereby affecting the yield of the subsequent polishing, such as scratches, black and white spots, etc. The existing grinding process has defects such as high chemical fiber liquid pollution, difficulty in cleaning, and the fiber height decreases with the number of grindings. Summary of the Invention

[0003] To solve the above problems, the primary purpose of the present invention is to provide a grinding sheet and a preparation method thereof, which are used to solve the technical problems of poor grinding effect and environmentally unfriendly grinding fluid caused by the current grinding process of grinding consumables.

[0004] To achieve the above object, the technical solution of the present invention is as follows:

[0005] The present invention provides a polishing sheet, comprising:

[0006] substrate;

[0007] The grinding layer is arranged on one side of the substrate and comprises silicon carbide micropowder. The silicon carbide micropowder is arranged in a concave-convex shape on the side away from the substrate.

[0008] The silicon carbide powder is arranged in a concave-convex pattern relative to the surface of the grinding layer on the side away from the substrate. This creates a non-uniform grinding surface, avoiding the over-cutting and fiber height reduction problems caused by traditional flat grinding. This allows the silicon carbide powder surface of the grinding sheet to grind the fiber end face of the ferrule to varying depths, thereby varying the fiber height within the ferrule. This concave-convex arrangement of the silicon carbide powder solves the problems of unstable fiber height control, chemical contamination, and low efficiency in traditional grinding processes, achieving high precision, environmental friendliness, and cost-effectiveness.

[0009] Furthermore, the grinding layer further comprises:

[0010] a connecting layer, covering one side of the substrate;

[0011] The silicon carbide micropowder is arranged on the connecting layer, and the connecting layer partially wraps the silicon carbide micropowder; the silicon carbide micropowder at least partially protrudes from the surface of the connecting layer on a side away from the substrate.

[0012] Furthermore, the substrate is PET polyester film.

[0013] Furthermore, the coarseness standard of the silicon carbide micropowder is 4000 mesh.

[0014] When the coarseness standard of silicon carbide micropowder is 4000 mesh, its high hardness characteristics can achieve ultra-precision grinding of optical fibers, semiconductors and other materials.

[0015] Furthermore, the connecting layer includes glue.

[0016] Furthermore, the polishing layer is entirely covered on the surface of the substrate.

[0017] Furthermore, the connecting layer entirely covers the surface of the substrate.

[0018] Furthermore, the silicon carbide powder is distributed on the entire surface of the connection layer, and the silicon carbide powder is arranged at intervals.

[0019] Furthermore, the grinding layer is fixedly connected to the substrate.

[0020] Furthermore, the silicon carbide particles and the connecting layer are fixedly connected, and the connecting layer is fixedly connected to the substrate.

[0021] The present invention also provides a method for preparing an abrasive sheet, comprising the steps of:

[0022] Mixing silicon carbide powder, acrylic resin, isocyanate, and diluent into a mixed liquid, stirring the mixed liquid at a speed r, ultrasonic power p, and stirring time T1 to form a slurry, and applying the slurry to the surface of the substrate;

[0023] The slurry surface is baked at a first temperature t1 and a first baking time T2 until it is no longer sticky and is rolled up; and a second baking is performed at a second temperature t2 and a second baking time T3 to form an abrasive sheet.

[0024] Furthermore, the mixing ratio of the silicon carbide powder, the acrylic resin, the isocyanate, and the diluent is 3:5:1:1.

[0025] Furthermore, the rotation speed r is 450 r / min; and / or the ultrasonic power p is 100 w; and / or the stirring time T1 is 45 min.

[0026] Furthermore, the first temperature t1 is 60° C.; and / or the first baking time T2 is 20 seconds.

[0027] Furthermore, the second temperature t2 is 40° C.; and / or the second baking time T3 is 12 hours.

[0028] Compared with the prior art, the beneficial effects of the present application are as follows: the grinding sheet includes: a substrate; a grinding layer, which is arranged on one side of the substrate and includes silicon carbide micropowder, and the silicon carbide micropowder is arranged in a concave-convex shape on the side away from the substrate. The silicon carbide micropowder is arranged in a concave-convex shape relative to the surface of the grinding layer on the side away from the substrate, and the concave-convex arrangement forms a non-uniform grinding surface, thereby avoiding the problems of over-cutting or fiber height reduction caused by traditional plane grinding, so that the silicon carbide micropowder surface of the grinding sheet can grind the optical fiber end face of the ferrule to different depths to obtain a change in the height of the optical fiber in the ferrule. The concave-convex arrangement design of silicon carbide micropowder solves the problems of unstable fiber height control, chemical pollution and low efficiency in traditional grinding processes, and combines high precision, environmental protection and economy.

[0029] The method for preparing an abrasive sheet includes: mixing silicon carbide micropowder, acrylic resin, isocyanate, and a diluent into a mixed liquid; stirring the mixed liquid at a rotation speed r, an ultrasonic power p, and a stirring time T1 to form a slurry; applying the slurry to a substrate surface; baking the slurry surface at a first temperature t1 and a first baking time T2 until it is no longer sticky and then rolling it up; and baking it again at a second temperature t2 and a second baking time T3 to form an abrasive sheet. The method for preparing the abrasive sheet is simple and increases the production efficiency of the abrasive sheet. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a structural schematic diagram of a grinding sheet provided by the present invention.

[0031] Figure 2 It is a schematic flow chart of a method for preparing an abrasive sheet provided by the present invention.

[0032] Figure 3 This is a test schematic diagram of polishing an optical fiber using a flat polishing sheet and water in Example 1.

[0033] Figures 4 to 6 This is the first set of test data for the grinding process of the existing flat grinding sheet in Example 1.

[0034] Figures 7 to 9 This is the second set of test data for the grinding process of the existing flat grinding sheet in Example 1.

[0035] Figures 10 to 12 This is the third set of test data for the grinding process of the existing flat grinding sheet in Example 1.

[0036] Figure 13 This is a test schematic diagram of polishing an optical fiber with the polishing sheet of the present application plus water in Example 2.

[0037] Figures 14 to 16 This is the first set of test data for the grinding process of the grinding sheet in Example 2.

[0038] Figures 17 to 19 This is the second set of test data for the grinding process of the grinding sheet in Example 2.

[0039] Figures 20 to 22 This is the third set of test data for the grinding process of the grinding sheet in Example 2.

[0040] Figure 23 This is a test schematic diagram of polishing optical fiber with black cloth and polishing liquid in Example 3.

[0041] Figures 24 to 26 This is the first set of test data for the grinding process of the black cloth in Example 3.

[0042] Figures 27 to 29 This is the second set of test data for the grinding process of the black cloth in Example 3.

[0043] Figures 30 to 32 This is the third set of test data for the grinding process of the black cloth in Example 3.

[0044] In the figure: 100, substrate; 200, grinding layer; 210, silicon carbide silicon powder; 220, connecting layer. DETAILED DESCRIPTION

[0045] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0046] To achieve the above object, the technical solution of the present invention is as follows:

[0047] See also Figures 1 to 32 The present invention provides a polishing sheet, comprising: a substrate 100; a polishing layer 200, which is arranged on one side of the substrate 100 and includes silicon carbide micropowder 210, and the silicon carbide micropowder 210 is arranged in a concave-convex shape on the side away from the substrate 100.

[0048] The silicon carbide powder 210 is arranged in a concave-convex pattern on the side of the polishing layer 200 facing away from the substrate 100. This creates a non-uniform grinding surface, avoiding the over-cutting and fiber height reduction problems associated with traditional flat polishing. This allows the silicon carbide powder 210 surface of the polishing sheet to polish the fiber end face of the ferrule to varying depths, thereby varying the fiber height within the ferrule. This concave-convex arrangement of the silicon carbide powder 210 solves the problems of unstable fiber height control, chemical contamination, and low efficiency associated with traditional polishing processes, achieving high precision, environmental friendliness, and cost-effectiveness.

[0049] Furthermore, the polishing layer 220 is entirely covered on the surface of the substrate 110 .

[0050] Furthermore, the grinding layer 22 is fixedly connected to the substrate 100 .

[0051] The grinding layer 220 completely covers the surface of the substrate 100, which can avoid local stress concentration or uneven processing and ensure the consistency of the workpiece surface. In addition, the grinding layer 220 completely covers the surface of the substrate 100, increasing the overall working area of ​​the grinding sheet, thereby improving the grinding efficiency of the grinding sheet in the future.

[0052] Furthermore, the polishing layer 200 also includes: a connecting layer 220, which is covered on one side of the substrate 100; silicon carbide micropowder 210 is arranged on the connecting layer 220, and the connecting layer 220 partially wraps the silicon carbide micropowder 210; the silicon carbide micropowder 210 at least partially protrudes from the surface of the connecting layer 220 on the side away from the substrate 100.

[0053] Furthermore, the substrate 100 is a PET polyester film.

[0054] Furthermore, the silicon carbide powder 210 has a 4000 mesh standard, meaning the particle diameter of the silicon carbide powder 210 is approximately 3 μm to 5 μm. The high hardness of the 4000 mesh standard allows for ultra-precision grinding of materials such as optical fibers and semiconductors.

[0055] Furthermore, the connection layer 220 includes glue.

[0056] Furthermore, the connection layer 220 entirely covers the surface of the substrate 100 .

[0057] Furthermore, the silicon carbide powder 210 is distributed on the entire surface of the connection layer 220 , and the silicon carbide powder 210 is arranged at intervals.

[0058] Furthermore, the silicon carbide particles 210 and the connecting layer 220 are fixedly connected, and the connecting layer 220 is fixedly connected to the substrate 100 .

[0059] The connecting layer 220 is entirely coated on the surface of the substrate 100, and the silicon carbide micropowder 210 is distributed on the entire surface of the connecting layer 220, and the silicon carbide micropowder 210 is arranged at intervals. Therefore, when the grinding sheet is used for grinding in the future, high-precision grinding and uniform grinding can be achieved. The silicon carbide micropowder 210 is arranged at intervals to avoid abrasive accumulation, ensuring that each silicon carbide micropowder 210 effectively participates in cutting, reducing waste, and the evenly distributed abrasive wears more uniformly, avoiding local premature failure, and the overall wear resistance of the grinding sheet is improved.

[0060] The polishing sheet provided by the present invention features a concave-convex arrangement of silicon carbide powder 210 relative to the surface of the polishing layer 200 on the side facing away from the substrate 100. This uneven arrangement creates a non-uniform grinding surface, avoiding the overcutting and fiber height reduction problems associated with conventional flat grinding. This allows the surface of the silicon carbide powder 210 on the polishing sheet to grind the fiber end face of the ferrule to varying depths, thereby varying the fiber height within the ferrule. This concave-convex arrangement of silicon carbide powder 210 overcomes the problems of unstable fiber height control, chemical contamination, and low efficiency associated with conventional grinding processes, achieving high precision, environmental friendliness, and cost-effectiveness.

[0061] The present invention also provides a method for preparing an abrasive sheet, comprising the steps of:

[0062] Step 100: Silicon carbide powder, acrylic resin, isocyanate, and diluent are mixed into a mixed liquid, and the mixed liquid is stirred under the conditions of a rotation speed r, ultrasonic power p, and stirring time T1 to form a slurry, and the slurry is applied to the surface of the substrate 100.

[0063] In step 100 , the mixing ratio of silicon carbide powder, acrylic resin, isocyanate, and diluent is 3:5:1:1.

[0064] In step 100 , the rotation speed r is 450 r / min; and / or the ultrasonic power p is 100 w; and / or the stirring time T1 is 45 min.

[0065] Specifically, in step 100, 30 parts of 4000# silicon carbide micropowder 210, 50 parts of acrylic resin, 10 parts of isocyanate, and 10 parts of diluent are used, and a spiral stirring rod is used to stir them evenly at a speed of 450r / min under the action of ultrasound. The ultrasonic power is 100w and the stirring time is 45min to form a flowing liquid as the slurry to be used. Then, a scraper is used to evenly apply the slurry to one side surface of the substrate 100.

[0066] Step 200: baking the slurry surface at a first temperature t1 and a first baking time T2 until it is no longer sticky and then rolling it up; and baking it again at a second temperature t2 and a second baking time T3 to form an abrasive sheet.

[0067] In step 200 , the first temperature t1 is 60° C.; and / or the first baking time T2 is 20 seconds.

[0068] In step 200 , the second temperature t2 is 40° C.; and / or the second baking time T3 is 12 hours.

[0069] Specifically, in step 200, the slurry is first baked in a 60°C oven for 20 seconds to allow the surface of the slurry to dry until the surface of the slurry is non-sticky, and then rolled up; a second baking is performed, the second baking temperature is 40°C, and the baking time is 12 hours.

[0070] After step 200 is completed, that is, after baking, a grinding sheet is formed, which can be used to grind with water without repeatedly adding fiber liquid. It is easy to clean and belongs to water-based grinding. There is no residue, and the yield rate is steadily improved.

[0071] Based on the above-mentioned polishing sheet provided by this application, in order to verify the actual effect of the polishing sheet and its polishing process, a traditional flat polishing sheet, the polishing sheet of this application, and a traditional black cloth were used as polishing consumables to perform polishing tests on the ferrule and optical fiber. The specific examples are as follows:

[0072] Example 1:

[0073] In Example 1, a common flat grinding sheet is added with water to realize the fiber drawing action. Specifically, the common flat grinding sheet includes: a substrate, a coating is provided on the surface of the substrate, the coating is a silicon carbide coating, and the coating is a flat coating. The substrate is made of PET. The common flat grinding sheet is used to perform a grinding test on the optical fiber on an automatic grinding machine. During the test, a certain time, speed, and pressure need to be set. In the specific embodiment, the time is set to 70s, the speed is 120r / min, and the pressure parameter is 4000g for the flat grinding sheet. The optical fiber height test data obtained by the grinding test is shown in Figure 3~ Figure 12 As shown in the figure, the optical fiber heights in the flat polishing sheets are all negative values. The optical fiber heights are not raised, but are ground down instead. This shows that if the coating is simply a flat coating, it has no ability to pull the optical fiber.

[0074] Example 2:

[0075] This embodiment 2 specifically relates to a process for pure water-based fiber drawing and polishing of an MPO / MT optical fiber connector, and more specifically relates to a process for pure water-based fiber drawing and polishing that achieves a change in fiber height by using the granularity of the surface of its grinding consumables. The grinding sheet includes a substrate, a coating on the surface of the substrate, a silicon carbide coating, and the coating is not flat but has an uneven granularity. The substrate is made of PET. The grinding sheet of this application is used to perform a grinding test on an automatic grinding machine for optical fiber. The grinding sheet includes silicon carbide micropowder 210 with a convex shape. The time for the grinding sheet is set to 80s, the rotation speed is 160r / min, and the pressure parameter is 7000g. The optical fiber height test data obtained by the grinding test is as follows: Figures 13 to 22 As shown, the optical fiber height has a certain value, about 1300 to 1600, and has a certain fiber height. Therefore, the concave-convex structure of the silicon carbide micropowder 210 makes the fiber height control more stable. The grinding disc of the present application directly uses water to replace traditional grinding fluids, such as grinding fluids containing chemical additives, to avoid residual contamination such as scratches, black and white spots and other defects. And it is convenient to clean after grinding, saving time and improving production capacity. In addition, the use of the grinding disc of the present application can save the cost of purchasing grinding fluid and waste liquid treatment, which meets the requirements of green production.

[0076] Example 3:

[0077] In Example 3, abrasive liquid is added to black cloth or white cloth to complete the fiber drawing. Specifically, black cloth or white cloth is selected as raw material polyester fiber. The optical fiber is ground on an automatic grinding machine using black cloth or white cloth. The parameters set in the black cloth grinding test are consistent with the parameters set for the grinding test of the grinding sheet in Example 2, that is, the grinding sheet setting time is 80s, the speed is 160r / min, and the pressure parameter is 7000g. Figures 23 to 32 It can be seen from the data that the optical fiber height also reaches 1300-1600, which is similar to the data of the polishing test using the polishing sheet in the embodiment.

[0078] From Examples 1 and 2, it can be seen that although the coatings of the substrates are the same, the pulling action cannot be achieved without the uneven graininess. From Examples 2 and 3, it can be seen that although the substrates are different, the effects achieved are basically the same. Therefore, the abrasive sheet of the present application can completely replace the traditional black cloth or white cloth. Therefore, the abrasive sheet with water in the present application can replace the traditional black cloth with abrasive liquid process, and can achieve a certain fiber height. The most obvious effect is that the abrasive sheet with water in the abrasive sheet grinding process is easy to clean, and no particles of the abrasive liquid will remain to affect the next step of polishing, reducing the proportion of polishing scratches, thereby further improving the yield rate.

[0079] It should be noted that traditional polyurethane polishing velvet can be reused, but the wear of the velvet will cause the optical fiber to be missed, thereby causing physical damage to the end face of the optical fiber and the appearance of some cracks. The polishing sheet in this application is a disposable polishing consumable, so that after the optical fiber is polished by the polishing sheet, the fiber height consistency obtained is greatly improved, completely solving the problem of fiber height reduction in traditional processes.

[0080] The above-mentioned grinding sheet and the method for preparing the grinding sheet provided in this application are applied to the process of fine grinding. Fiber drawing can be achieved using the above-mentioned grinding sheet and water. In the process of grinding optical fibers using this grinding sheet, PET polyester film replaces the traditional polyurethane polishing velvet cloth as the substrate 100 or carrier, and water replaces the traditional grinding liquid as the grinding medium. Fiber drawing is achieved with the help of the silicon carbide micropowder 210 of the grinding layer 200, that is, with the help of the uneven particles on the surface of the grinding consumables. The silicon carbide micropowder 210 on the surface of the grinding layer 200 is used to provide a non-planar grinding state for the ferrule, that is, to make the surface of the ferrule undulate up and down, thereby achieving changes in fiber height.

[0081] Based on the above-mentioned polishing sheet and the preparation method of the polishing sheet, the process flow of using the polishing sheet to polish the optical fiber has the following advantages: 1. The optical fiber is polished directly by adding water to the polishing sheet. Water is added once and there is no need to repeatedly add fiber liquid. The consistency of the fiber height obtained after polishing is greatly improved, which completely solves the problem of fiber height decrease in traditional processes and the polishing is stable throughout the process; 2. The optical fiber is polished by adding water to the polishing sheet, that is, water-based polishing, which leaves no residue, saves 1 to 3 minutes per plate, and the production capacity increases linearly. It is also easy to clean and the efficiency is improved; 3. The end face polishing quality of the optical fiber is more stable, the scrap rate is greatly reduced, the quality is more guaranteed, and the yield exceeds 95%; 4. By replacing traditional polishing liquid with water, the use of chemical fiber liquid is reduced, the cost of waste liquid treatment is reduced, green production is more compliant, and environmental protection and energy saving are achieved.

[0082] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A polishing sheet, characterized in that: include: substrate; The grinding layer is arranged on one side of the substrate and comprises silicon carbide micropowder. The silicon carbide micropowder is arranged in a concave-convex shape on the side away from the substrate.

2. The polishing sheet according to claim 1, wherein: The grinding layer also includes: a connecting layer, covering one side of the substrate; The silicon carbide micropowder is arranged on the connecting layer, and the connecting layer partially wraps the silicon carbide micropowder; the silicon carbide micropowder at least partially protrudes from the surface of the connecting layer on a side away from the substrate.

3. The polishing sheet according to claim 1, wherein: The substrate is PET polyester film.

4. The polishing sheet according to claim 1, wherein: The coarseness standard of the silicon carbide micropowder is 4000 mesh.

5. The polishing sheet according to claim 1, wherein: The connecting layer includes glue.

6. A method for preparing an abrasive sheet, characterized in that: Including steps: Mixing silicon carbide powder, acrylic resin, isocyanate, and diluent into a mixed liquid, stirring the mixed liquid at a speed r, ultrasonic power p, and stirring time T1 to form a slurry, and applying the slurry to the surface of the substrate; The slurry surface is baked at a first temperature t1 and a first baking time T2 until it is no longer sticky and is rolled up; and a second baking is performed at a second temperature t2 and a second baking time T3 to form an abrasive sheet.

7. A method for preparing an abrasive sheet according to claim 6, characterized in that: The mixing ratio of the silicon carbide micropowder, the acrylic resin, the isocyanate, and the diluent is 3:5:1:

1.

8. A method for preparing an abrasive sheet according to claim 6 or 7, characterized in that: The rotation speed r is 450 r / min; and / or the ultrasonic power p is 100 w; and / or the stirring time T1 is 45 min.

9. The method for preparing an abrasive sheet according to claim 6, wherein: The first temperature t1 is 60° C.; and / or the first baking time T2 is 20 seconds.

10. A method for preparing an abrasive sheet according to claim 6 or 9, characterized in that: The second temperature t2 is 40° C.; and / or the second baking time T3 is 12 hours.

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