A high grinding force polishing pad for crystal polishing and a production process thereof

Abstract

The application discloses a high-grinding-force polishing pad for crystal polishing and a production process thereof, and belongs to the technical field of crystal polishing. The high-grinding-force polishing pad for crystal polishing comprises a polishing pad main body, four stabilizing rings are arranged in the polishing pad main body, and a toughening sheet is arranged between the four stabilizing rings; the toughening sheet comprises a bending-resistant strip, a pressure-resistant sheet and a fixing column; the stabilizing ring is prepared from PVC resin; and the toughening sheet is prepared from a block copolymer of SBS toughening material. The application solves the problems that the existing polishing pad consumes a large amount of energy for polishing work of a crystal, influences the service life and is not conducive to long-term use. The toughening sheet is uniformly arranged outside the stabilizing ring, the position of the toughening sheet is limited, the polishing pad main body is kept stable, the toughening sheets are arranged between the four stabilizing rings in sequence, the stabilizing ring and the toughening sheet can keep position stable in high-speed rotation, the working precision is improved, and the service life is prolonged.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of crystal polishing, in particular to a high-grinding-force polishing pad for crystal polishing and a production process thereof. BACKGROUND

[0002] In the process of polishing and polishing wafer products, a separate polishing pad is needed at the bottom of the wafer to improve the efficiency of polishing and polishing, and the wax-free pad is a new type of pad, which is a specially made polishing sheet containing glass fiber, resin and other materials. According to the needs of the diameter and thickness of the pre-polishing single wafer, grooves are made on the sheet for use. The sheet can be firmly attached to the polished metal carrier, and a layer of pure water is lightly applied to the groove, so that the single wafer can be adsorbed and polished. It is very suitable for single-sided polishing of sapphire sheets, LED substrates, wax-free silicon wafers, glass panels, optical crystal sheets and laser crystal sheets.

[0003] A polishing pad and a method for preparing the polishing pad are disclosed in Chinese Patent No. CN108161713B. The preparation method of the polishing pad comprises the following steps: mixing liquid pre-polymer, curing agent and hollow micro-element at 50-85℃ to form a curable mixture, the viscosity of the curable mixture is 3000-20000cps, and the gel is cured, and the polishing pad is obtained; the liquid pre-polymer is a polyurethane pre-polymer prepared by reacting polyol and isocyanate; the gel mold adopts real-time temperature sensor and first digital control system on the mold, infrared temperature instrument and second digital control system on the exhaust hood to realize the regulation and control of the temperature of the reaction material in the mold. The patent gives the optimal process conditions in the pouring and gelatinization process, the gelatinization mold can accurately and real-timely regulate the gelatinization temperature change, the polishing pad of the present application is uniform from top to bottom, has few stripes, uniform density and performance, and the yield of the product is close to 100%.

[0004] The polishing pad of the above-mentioned patent consumes a lot in the actual use process of polishing the crystal, affects the service life, and is not conducive to long-term use. SUMMARY

[0005] The present application provides a high-grinding-force polishing pad for crystal polishing and a production process thereof, which solves the problem of the polishing pad in the above background technology, which consumes a lot in the actual use process of polishing the crystal, affects the service life, and is not conducive to long-term use.

[0006] To achieve the above-mentioned purpose, the present application provides the following technical scheme: a high-grinding-force polishing pad for crystal polishing, comprising a polishing pad main body, four stabilizing rings are arranged in the interior of the polishing pad main body, a toughening sheet is arranged between the four stabilizing rings, the toughening sheet comprises a bending-resistant strip, a pressure-resistant sheet and a fixing column.

[0007] The stabilizing ring is made of PVC resin;

[0008] The toughening sheet is a block copolymer prepared by using SBS toughening material.

[0009] Preferably, it is prepared from the following components in parts by weight:

[0010] Polyurethane 100-120 parts;

[0011] 10-12 parts of modified curing agent;

[0012] 100-120 parts of epoxy resin polymer;

[0013] 30-35 parts of PVC resin;

[0014] 50-60 parts of SBS toughening material.

[0015] Preferably, the outer surface of the polishing pad body is provided with an integrally formed polishing surface, an integrally formed polishing head is provided in the middle of the polishing surface, and the four stabilizing rings are arranged in sequence on the surface of the polishing surface.

[0016] Preferably, a connecting shock-absorbing pad is installed at the lower end of the polishing pad body, and the connecting shock-absorbing pad is adhesively connected to the polishing pad body. The lower end surface of the connecting shock-absorbing pad is provided with an integrally formed positioning groove, and the interior of the positioning groove is provided with an integrally formed mounting groove. The outside of the mounting groove is surrounded by fastening holes, and the fastening holes are used to fix the connecting shock-absorbing pad and the polishing machine.

[0017] Preferably, a plurality of toughening sheets are provided, and the plurality of toughening sheets are fixedly connected to the stabilizing ring. The toughening sheets are embedded in the polishing pad body and fit the polishing pad body.

[0018] Preferably, four anti-bending strips are provided, and the four anti-bending strips are all fixed at the front end of the pressure-resistant sheet. The fixing column is used to fix the toughening sheet, and the fixing column is embedded in the polishing pad body and fixedly connected to the polishing pad body.

[0019] A production process for a high-grinding-force polishing pad for crystal polishing comprises the following steps:

[0020] Step 1: Heat and melt the polyurethane, modified curing agent and epoxy resin polymer and pour them into a mold. The mold is heated to 35-45°C, and the materials in the mold are naturally foamed to form the polishing pad body.

[0021] Step 2: Extrude the PVC resin into rings, and process them into four stabilizing rings of different diameters according to the size of the polishing pad;

[0022] Step three: the stable ring is bonded with the formed material by adhesive, and then is pressed into the polishing pad body. After that, the adhesive is cured by baking again. After curing, the polishing pad is polished to be flat;

[0023] Step four: the SBS toughening material is heated to make the styrene and butadiene melt and flow into strips. After cooling, the toughening sheet is obtained by cutting;

[0024] Step five: the cut toughening sheet is installed between the four stable rings, and the distance between each toughening sheet is the same;

[0025] Step six: the polishing pad body is baked to heat, and the toughening sheet is embedded in the polishing pad body. Then, the polishing pad with a flat surface is obtained by polishing with a high-precision lathe.

[0026] Preferably, in step two, the extrusion of PVC resin into a ring includes the following steps:

[0027] The PVC resin pellets, lubricant, stabilizer, modifier and colorant are mixed and heated;

[0028] After mixing, the extrusion is carried out by a screw extruder;

[0029] During the extrusion molding process, ring dies are arranged at the terminal to prepare four sizes of stable rings through four different dies.

[0030] Preferably, in step four, the production process of the toughening sheet includes the following steps:

[0031] The plastic toughening composite material is obtained by using melt mixing extrusion with polypropylene and SBS as the main material, calcium carbonate as the filler, and ethylene-vinyl acetate grafted maleic anhydride as the solvent.

[0032] The mechanical properties, flow properties, heat resistance and thermal properties of the composite material are tested and analyzed to observe the influence law of SBS;

[0033] The screw length-diameter ratio L / D of the extruder is 24:1, the extrusion melt temperature range is set to 148-198℃, the feeding section temperature is less than 80℃, and the pressure-resistant sheet is obtained by extrusion molding.

[0034] After extrusion molding, three groups of SBS anti-bending strips are adhered to the outside of the pressure-resistant sheet, and SBS fixing columns are adhered outside. After heating and adhering, the toughening sheet is obtained by cooling.

[0035] Preferably, in step six, the polishing process of the polishing pad includes the following steps:

[0036] The polishing pad body is placed in the lower die and heated. The toughening sheet and the stable ring protruding from the surface of the polishing pad body are polished.

[0037] The rubber is pasted on the back of the polishing pad body, and the damping pad is adhered and connected;

[0038] Grooves and holes are engraved on the surface of the connected damping pad, and the molding process is completed.

[0039] Compared with the prior art, the present application has the following advantages:

[0040] 1、The present application sets the stabilizing ring and the toughening sheet on the surface of the polishing pad body, and the polishing surface of the polishing pad body is reinforced and toughened, SBS can flow after being heated, and is easy to be molded, after cooling to room temperature, the polystyrene chain segment is gathered into glassy micro area, which plays a role of physical crosslinking point for the polybutadiene chain segment, so that the material exhibits the characteristics of rubber, improves the toughness, impact strength, bending resistance and low temperature resistance of the plastic, SBS has good compatibility with polyurethane, improves the service life of the polishing pad, is conducive to long-term work, and realizes the best working effect.

[0041] 2、The toughening sheet uniformly surrounds the outside of the stabilizing ring, the position of the toughening sheet is limited, the polishing pad body maintains sufficient stability, PVC resin is a polar non-crystalline polymer, and the molecules have strong interaction, which is a hard and brittle material with low impact strength, after adding the impact modifier, the elastomer particles of the impact modifier can reduce the total crazing initiation stress, and prevent the crazing from expanding and growing by using the deformation and shear band of the particles themselves, so as to achieve the purpose of impact resistance, thereby improving the working life, and the toughening sheets arranged between the four stabilizing rings can keep the position of the stabilizing ring and the toughening sheet stable during high-speed rotation, improve the working precision, and prolong the service life. DETAILED DESCRIPTION

[0042] Figure 1 It is a front view of the present application;

[0043] Figure 2 It is a bottom view of the present application;

[0044] Figure 3 It is a front view of the internal structure of the present application;

[0045] Figure 4 It is a top view of the internal structure of the present application;

[0046] Figure 5 It is a structure diagram of the toughening sheet of the present application.

[0047] In the figure: 1, polishing pad main body; 101, polishing surface; 102, polishing head; 2, connecting damping pad; 201, positioning groove; 202, mounting groove; 203, fastening hole; 3, stabilizing ring; 4, toughening piece; 401, anti-bending strip; 402, pressure-resistant piece; 403, fixing column. DETAILED DESCRIPTION

[0048] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0049] In order to solve the problem that the existing polishing pad consumes a lot in polishing work of crystals in actual use, affects the service life, and is not conducive to long-term use, please refer to Figure 1 Figure 5 The embodiment provides the following technical solutions:

[0050] A high-grinding-force polishing pad for polishing crystals comprises a polishing pad main body 1, four stabilizing rings 3 are arranged in the polishing pad main body 1, and a toughening piece 4 is arranged between the four stabilizing rings 3. The toughening piece 4 comprises an anti-bending strip 401, a pressure-resistant piece 402 and a fixing column 403. The toughening pieces 4 arranged in sequence between the four stabilizing rings 3 can keep the stabilizing rings 3 and the toughening pieces 4 stable in high-speed rotation, improve the working precision, and prolong the service life.

[0051] The stabilizing ring 3 is prepared from PVC resin. The PVC resin is a polar non-crystalline polymer, has strong interaction between molecules, is a hard and brittle material, and has low impact strength. After adding an impact modifier, the elastomer particles of the impact modifier can reduce the total craze initiation stress, prevent the craze from expanding and growing by using the deformation and shear band of the particles themselves, and absorb the impact energy transmitted into the material body, so that the impact resistance is achieved, and the working life is improved.

[0052] The toughening piece 4 is prepared from a block copolymer of SBS toughening material. The SBS toughening material plays a role of a physical crosslinking point for a polybutadiene segment, so that the material exhibits the characteristics of rubber, the toughness, impact strength, bending resistance and low-temperature resistance of the plastic are improved, SBS has good compatibility with polyurethane, the service life of the polishing pad is improved, long-term work is facilitated, and the best working effect is achieved.

[0053] ​The outer surface of the polishing pad body 1 is provided with an integrally formed polishing surface 101, the middle of the polishing surface 101 is provided with an integrally formed polishing head 102, and four stabilizing rings 3 are arranged in sequence on the surface of the polishing surface 101. The crystal surface is polished and polished by the polishing head 102 and the polishing surface 101.

[0054] The lower end of the polishing pad body 1 is provided with a connecting damping pad 2, the connecting damping pad 2 is adhesively connected with the polishing pad body 1, the lower end surface of the connecting damping pad 2 is provided with an integrally formed positioning groove 201, the inside of the positioning groove 201 is provided with an integrally formed mounting groove 202, the outside of the mounting groove 202 is surrounded by a fastening hole 203, the fastening hole 203 is used for fixing the connecting damping pad 2 and the polishing machine, and the bottom of the connecting damping pad 2 is opened for installation work, so as to be disassembled and replaced, facilitating continuous work.

[0055] The toughening sheet 4 is provided with a plurality of toughening sheets 4, the plurality of toughening sheets 4 are fixedly connected with the stabilizing ring 3, the toughening sheet 4 is embedded in the inside of the polishing pad body 1 and is attached with the polishing pad body 1, four stabilizing rings 3 are arranged on the polishing pad body 1, and the toughening sheet 4 is uniformly surrounded by the stabilizing ring 3 outside, so that the position of the toughening sheet 4 is limited.

[0056] The anti-bending strip 401 is provided with four anti-bending strips 401, the four anti-bending strips 401 are fixed at the front end of the pressure-resistant sheet 402, the fixed column 403 is used for fixing the toughening sheet 4, and the fixed column 403 is embedded in the polishing pad body 1 and fixedly connected with the polishing pad body 1. In the production work, the fixed column 403 is embedded in the inside of the polishing pad body 1 for connection work, and in the long-term use process, the toughening sheet 4 is uniformly stressed by the cooperation of the anti-bending strip 401 and the pressure-resistant sheet 402, so as to improve the use effect.

[0057] Specifically, four stabilizing rings 3 are arranged on the polishing pad body 1, the toughening sheet 4 is uniformly surrounded by the stabilizing ring 3 outside, so that the position of the toughening sheet 4 is limited, so that the polishing pad body 1 maintains sufficient stability, the PVC resin is a polar non-crystalline polymer, the molecules have strong interaction, it is a hard and brittle material, the impact strength is low, after adding the impact modifier, the elastomer particles of the impact modifier can reduce the total craze initiation stress, and can prevent the craze from expanding and growing by using the deformation and shear band of the particles themselves, and can absorb the impact energy transmitted into the material body, so as to achieve the purpose of impact resistance, thereby improving the working life, and the toughening sheet 4 arranged in sequence between the four stabilizing rings 3 can still maintain the position stable in high-speed rotation, improve the working precision, and prolong the service life.

[0058] Example one:

[0059] A high-grinding-force polishing pad for crystal polishing is prepared from the following components by weight fraction:

[0060] Polyurethane 100 parts;

[0061] Modified curing agent 10 parts;

[0062] Epoxy resin polymer 100 parts;

[0063] PVC resin 30 parts;

[0064] SBS toughening material 50 parts.

[0065] A production process of a high-grinding-force polishing pad for crystal polishing, comprising the following steps:

[0066] Step one: after heating and melting the polyurethane, modified curing agent and epoxy resin polymer, pour them into a mold, heat the mold to 35℃, and naturally foam the material in the mold to form a polishing pad body 1. The polishing pad uses epoxy resin as the base material, has mechanical properties and corrosion resistance;

[0067] Step two: extrude the PVC resin into a ring, and according to the size of the polishing pad, process four stable rings 3 of different diameters to improve the stability of the working position;

[0068] Step three: bond the stable rings 3 to the formed material through an adhesive, press them into the polishing pad body 1, and then cure the adhesive by re-baking. After curing, polish and smooth the surface, quickly install and prepare the work;

[0069] Step four: heat the SBS toughening material, and make it flow into a strip after being heated and melted. After cooling, cut the toughening sheet 4. After being heated, the SBS material can flow and be easily processed. After cooling to room temperature, the polystyrene chain segment aggregates into a glassy microzone, which acts as a physical crosslinking point for the polybutadiene chain segment, thereby making the material exhibit rubber properties, improving the toughness, impact strength, bending resistance and low temperature resistance of the plastic. SBS has good compatibility with polyurethane, which improves the service life of the polishing pad, is conducive to long-term work, and achieves the best working effect. The polishing pad body 1 has elasticity through the toughening sheet 4, which improves the use effect;

[0070] Step five: install the cut toughening sheet 4 between the four stable rings 3, and the distance between each toughening sheet 4 is the same. The arrangement of the toughening sheet 4 between the four stable rings 3 enables the stable ring 3 and the toughening sheet 4 to remain positionally stable during high-speed rotation, improves working precision, and prolongs service life;

[0071] Step six: bake and heat the polishing pad body 1, embed the toughening sheet 4 into the polishing pad body 1, and then polish it through a high-precision lathe to obtain a polishing pad with a smooth surface. The polishing pad is connected through the embedding of the fixing column 403 into the polishing pad body 1, which facilitates the preparation work.

[0072] The extruding ring work of the PVC resin in step two includes the following steps:

[0073] Mix and heat the PVC resin pellets, lubricants, stabilizers, modifiers, and complementary agents;

[0074] After the mixing is completed, perform the extrusion work through a screw extruder;

[0075] During the extrusion molding process, a ring mold is set at the terminal, and four different molds are used to produce four sizes of stable rings 3, which have heat-resistant effects and improve the working effect.

[0076] The production process of the toughening sheet 4 in step four includes the following steps:

[0077] Use polypropylene and SBS as the main materials, calcium carbonate as the filler, and ethylene-vinyl acetate grafted maleic anhydride as the compatibilizer to obtain a plastic toughening composite material through melt mixing extrusion;

[0078] Test and analyze the mechanical properties, flow properties, heat resistance, and thermal properties of the composite material, observe the influence law of SBS, add a test process, and improve the product quality of SBS;

[0079] The screw length-diameter ratio L / D of the extruder is 24:1, the extrusion melt temperature range is set to 148°C, the feeding section temperature is less than 80°C, and the pressure-resistant sheet 402 is obtained through extrusion molding;

[0080] After extrusion molding, three groups of SBS anti-bending strips 401 are bonded to the outside of the pressure-resistant sheet 402, and SBS fixing columns 403 are adhered to the outside. Heat them to bond, then cool them to obtain the toughening sheet 4. In the production work, the fixing columns 403 are embedded in the inside of the polishing pad main body 1 for connection work. During long-term use, the toughening sheet 4 is uniformly stressed through the cooperation of the anti-bending strips 401 and the pressure-resistant sheet 402 to improve the use effect.

[0081] The polishing process of the polishing pad in step six includes the following steps:

[0082] Place the polishing pad main body 1 in the lower mold and heat it. Polish the toughening sheet 4 and the stable ring 3 protruding from the surface of the polishing pad main body 1. The four stable rings 3 are arranged in order on the polishing surface 101. The polishing head 102 and the polishing surface 101 polish and polish the crystal surface;

[0083] Paste the glue on the back of the polishing pad main body 1 and adhere the connection shock pad 2;

[0084] Groove and punch on the surface of the connection shock pad 2 to complete the molding process.

[0085] Embodiment two:

[0086] A high grinding force polishing pad for crystal polishing is prepared from the following components by weight parts:

[0087] Polyurethane 120 parts;

[0088] Modified curing agent 12 parts;

[0089] Epoxy resin polymer 120 parts;

[0090] PVC resin 35 parts;

[0091] SBS toughening material 60 parts.

[0092] A production process of a high grinding force polishing pad for crystal polishing, comprising the following steps:

[0093] Step one: after heating and melting the polyurethane, modified curing agent and epoxy resin polymer, pour them into the mold, heat the mold to 40℃, and the material in the mold foams naturally to form the polishing pad body 1. The polishing pad uses epoxy resin as the base material, which has mechanical properties and corrosion resistance;

[0094] Step two: extrude the PVC resin into a ring, and according to the size of the polishing pad, process four different diameter stabilizing rings 3, which are evenly distributed to improve the stability of the working position;

[0095] Step three: the stabilizing ring 3 is bonded to the formed material through an adhesive, and then pressed into the polishing pad body 1. The adhesive is cured again after baking, and then polished and leveled for preliminary installation and preparation;

[0096] Step four: heat the SBS toughening material, heat the styrene and butadiene to make them flow into strips after melting, and then cut the toughening sheet 4 after cooling. The SBS material can flow after heating, which is easy to process. After cooling to room temperature, the polystyrene chain segment aggregates into a glassy microzone, which plays a role of physical crosslinking point for the polybutadiene chain segment, so that the material exhibits the characteristics of rubber, improves the toughness, impact strength, bending resistance and low temperature resistance of the plastic. SBS has good compatibility with polyurethane, which improves the service life of the polishing pad, is conducive to long-term work, and achieves the best working effect. The polishing pad body 1 has elasticity through the toughening sheet 4, which improves the use effect;

[0097] Step five: install the cut toughening sheet 4 between the four stabilizing rings 3, and the distance between each toughening sheet 4 is the same. The toughening sheet 4 arranged between the four stabilizing rings 3 can still keep the position stable during high-speed rotation, which improves the working precision and prolongs the service life;

[0098] Step six: bake heating polishing pad body 1, insert the toughening piece 4 into the polishing pad body 1, and then polish by high-precision lathe to obtain a polishing pad with smooth surface. The polishing pad body 1 is connected by being embedded in the polishing pad body 1 through the fixing column 403, which facilitates the preparation work.

[0099] In step two, the extrusion into a ring of the PVC resin includes the following steps:

[0100] The PVC resin particles, lubricant, stabilizer, modifier and colorant are mixed and heated;

[0101] After mixing, the extrusion work is carried out by a screw extruder;

[0102] In the extrusion molding process, a ring mold is arranged at the terminal, and four different molds are used to prepare four sizes of stable rings 3. The stable ring 3 has heat-resistant effect, which improves the working effect.

[0103] In step four, the production process of the toughening piece 4 includes the following steps:

[0104] The plastic toughening composite material is obtained by using melt mixing extrusion with polypropylene and SBS as the main material, calcium carbonate as the filler, and ethylene-vinyl acetate grafted maleic anhydride as the phase solvent;

[0105] The mechanical properties, flow properties, heat resistance and thermal properties of the composite material are tested and analyzed to observe the influence law of SBS, and a test process is added to improve the product quality of SBS;

[0106] The length-diameter ratio L / D of the screw of the extruder is 24:1, the extrusion melt temperature range is set to 175℃, the feeding section temperature is less than 80℃, and the pressure-resistant piece 402 is obtained by extrusion molding;

[0107] After extrusion molding, three groups of SBS anti-bending strips 401 are adhered to the outside of the pressure-resistant piece 402, and SBS fixing columns 403 are adhered outside. After heating, the toughening piece 4 is obtained by cooling. In the production work, the toughening piece 4 is connected by being embedded in the polishing pad body 1 through the fixing column 403. In the long-term use process, the toughening piece 4 is uniformly stressed by cooperating the anti-bending strips 401 with the pressure-resistant piece 402, so as to improve the use effect.

[0108] In step six, the polishing pad polishing process includes the following steps:

[0109] The polishing pad body 1 is placed in the lower mold, heated, and the toughening piece 4 and the stable ring 3 protruding from the surface of the polishing pad body 1 are polished. The four stable rings 3 are arranged in sequence on the polishing surface 101. The polishing head 102 and the polishing surface 101 polish and polish the crystal surface;

[0110] The rubber is pasted on the back of the polishing pad body 1 to adhere the shock pad 2;

[0111] Grooves are engraved on the surface of the shock pad 2, and the molding process is completed.

[0112] Example three:

[0113] A high-grinding-force polishing pad for crystal polishing is prepared from the following components by weight:

[0114] 100 parts of polyurethane;

[0115] 10 parts of modified curing agent;

[0116] 100 parts of epoxy resin polymer;

[0117] 35 parts of PVC resin;

[0118] 60 parts of SBS toughening material.

[0119] A production process of a high-grinding-force polishing pad for crystal polishing includes the following steps:

[0120] Step one: after the polyurethane, modified curing agent and epoxy resin polymer are heated and melted, they are poured into a mold, the mold is heated to 45°C, and the materials in the mold are naturally foamed and formed to obtain a polishing pad body 1. The polishing pad uses epoxy resin as the base material, has mechanical properties and corrosion resistance;

[0121] Step two: extrude the PVC resin into a ring, and according to the size of the polishing pad, process four different diameter stabilizing rings 3 to improve the stability of the working position;

[0122] Step three: the stabilizing ring 3 is bonded to the formed material through an adhesive, and then pressed into the polishing pad body 1. The adhesive is cured again by baking, and then polished and leveled for preliminary installation and preparation work;

[0123] Step four: heat the SBS toughening material, heat the styrene and butadiene to make them flow into strips after melting, and then cut the toughening sheet 4 after cooling. After being heated, the SBS material can flow and be easily processed. After cooling to room temperature, the polystyrene chain segment aggregates into a glassy microzone, which acts as a physical crosslinking point for the polybutadiene chain segment, thereby making the material exhibit the characteristics of rubber, improving the toughness, impact strength, bending resistance, low temperature resistance of the plastic, and improving the service life of the polishing pad. It is conducive to long-term work and achieves the best working effect. The toughening sheet 4 makes the polishing pad body 1 elastic and improves the use effect;

[0124] Step five: the cut toughening piece 4 is installed between the four stable rings 3, the distance between each toughening piece 4 is the same, and the toughening pieces 4 arranged in turn between the four stable rings 3 can still keep stable position in high-speed rotation, improve the working precision and prolong the service life;

[0125] Step six: bake the polishing pad body 1, embed the toughening piece 4 into the polishing pad body 1, and then polish by high-precision lathe to get the polishing pad with smooth surface. The polishing pad body 1 is connected by embedding the fixing column 403 into the polishing pad body 1, which is convenient for preparation work.

[0126] In step two, the extrusion ring work of PVC resin includes the following steps:

[0127] Mix and heat the PVC resin granules, lubricant, stabilizer, modifier and complementary agent;

[0128] After mixing, extrude by screw extruder;

[0129] In the extrusion molding process, ring mold is set at the terminal, and four different molds are used to prepare four sizes of stable rings 3. The stable ring 3 has heat resistance effect, which improves the working effect.

[0130] In step four, the production process of toughening piece 4 includes the following steps:

[0131] Take polypropylene and SBS as main materials, calcium carbonate as filler, and ethylene-vinyl acetate grafted maleic anhydride as phase solvent, and plastic toughening composite material is obtained by melt mixing extrusion;

[0132] Test and analyze the mechanical properties, flow properties, heat resistance and thermal properties of the composite material, observe the influence law of SBS, add test process, and improve the product quality of SBS;

[0133] The length-diameter ratio L / D of the screw of the extruder is 24:1, the extrusion melt temperature range is set to 198℃, the feeding section temperature is less than 80℃, and the pressure-resistant piece 402 is obtained by extrusion molding;

[0134] After extrusion molding, three groups of SBS anti-bending strips 401 are adhered to the outside of the pressure-resistant piece 402, and SBS fixing columns 403 are adhered outside. Heat to adhere, and then cool to obtain the toughening piece 4. In the production work, the toughening piece 4 is connected by embedding the fixing column 403 into the polishing pad body 1. During long-term use, the toughening piece 4 is uniformly stressed by the cooperation of the anti-bending strip 401 and the pressure-resistant piece 402, so as to improve the use effect.

[0135] In step six, the polishing pad polishing process includes the following steps:

[0136] Put the polishing pad body 1 in the lower mold, heat, polish the toughening piece 4 and the stabilizing ring 3 protruding from the surface of the polishing pad body 1, and polish the crystal surface through the polishing head 102 and the polishing surface 101;

[0137] Paste the glue on the back of the polishing pad body 1, and adhere the shock pad 2;

[0138] Carve grooves on the surface of the shock pad 2, and complete the forming process.

[0139] Comparative Example 1:

[0140] The crystal polishing pad is prepared from the following components by weight:

[0141] 100 parts of polyurethane;

[0142] 10 parts of modified curing agent;

[0143] 100 parts of epoxy resin polymer.

[0144] The preparation process is as follows:

[0145] Step 1: Pour the polyurethane, modified curing agent and epoxy resin polymer into the mold after melting, heat the mold to 35℃, and naturally foam the material in the mold to form the polishing pad body 1. The polishing pad uses epoxy resin as the base material, which has mechanical properties and corrosion resistance;

[0146] Step 2: Extrude PVC resin into a ring, and process four different diameter stabilizing rings 3 according to the size of the polishing pad. The uniformly distributed four stabilizing rings 3 improve the stability of the working position;

[0147] Step 3: The stabilizing ring 3 is bonded to the formed material by adhesive, and then pressed into the polishing pad body 1. The adhesive is cured again after baking, and then polished and leveled for preliminary installation and preparation;

[0148] Step 4: Heat the SBS toughening material, heat the styrene and butadiene to make it flow into a strip after melting, and then cut it to obtain the toughening piece 4. The SBS material can flow after heating, which is easy to process. After cooling to room temperature, the polystyrene chain segment aggregates into a glassy microzone, which plays a role of physical crosslinking point for the polybutadiene chain segment, so that the material exhibits the characteristics of rubber, improves the toughness, impact strength, bending resistance, low temperature resistance of plastic, and has good compatibility with polyurethane, which improves the service life of the polishing pad, is conducive to long-term work, realizes the best working effect, and makes the polishing pad body 1 elastic through the toughening piece 4 to improve the use effect;

[0149] Step five: the cut toughening sheet 4 is installed between the four stabilizing rings 3, the distance between each toughening sheet 4 is the same, and the toughening sheets 4 arranged in turn between the four stabilizing rings 3 can still keep stable position in high-speed rotation, improve working precision and prolong service life;

[0150] Step six: bake the polishing pad body 1, embed the toughening sheet 4 into the polishing pad body 1, and then polish by high-precision lathe to obtain a polishing pad with smooth surface. The polishing pad body 1 is connected by embedding the fixing column 403 into the polishing pad body 1, which is convenient for preparation work.

[0151] In step two, the extrusion ring work of PVC resin includes the following steps:

[0152] The PVC resin particles, lubricant, stabilizer, modifier and colorant are mixed and heated;

[0153] After mixing, the screw extruder is used for extrusion work;

[0154] During the extrusion molding process, a ring mold is arranged at the terminal, and four different molds are used to prepare four sizes of stabilizing rings 3. The stabilizing ring 3 has heat resistance effect, which improves the working effect.

[0155] In step four, the production process of the toughening sheet 4 includes the following steps:

[0156] The plastic toughening composite material is obtained by using melt mixing extrusion with polypropylene and SBS as the main material, calcium carbonate as the filler, and ethylene-vinyl acetate grafted maleic anhydride as the solvent.

[0157] The mechanical properties, flow properties, heat resistance and thermal properties of the composite material are tested and analyzed to observe the influence law of SBS, and a test process is added to improve the product quality of SBS;

[0158] The length-diameter ratio L / D of the screw of the extruder is 24:1, the extrusion melt temperature range is set to 148℃, the feeding section temperature is less than 80℃, and the pressure-resistant sheet 402 is obtained by extrusion molding;

[0159] After extrusion molding, three groups of SBS anti-bending strips 401 are adhered to the outside of the pressure-resistant sheet 402, and SBS fixing columns 403 are adhered outside. After heating, the toughening sheet 4 is obtained by cooling. In the production work, the fixing column 403 is embedded in the polishing pad body 1 for connection work. During long-term use, the toughening sheet 4 is uniformly stressed by the cooperation of the anti-bending strip 401 and the pressure-resistant sheet 402, so as to improve the use effect.

[0160] In step six, the polishing pad polishing process includes the following steps:

[0161] Put the polishing pad body 1 in the lower mold, heat, polish the toughening piece 4 and the stabilizing ring 3 protruding from the surface of the polishing pad body 1, and polish the crystal surface through the polishing head 102 and the polishing surface 101;

[0162] Paste the glue on the back of the polishing pad body 1, and adhere the shock-absorbing pad 2;

[0163] Carve grooves on the surface of the shock-absorbing pad 2, and complete the forming process.

[0164] Comparative Example Two:

[0165] The crystal polishing pad is prepared from the following components by weight:

[0166] 100 parts of polyurethane;

[0167] 10 parts of modified curing agent;

[0168] 100 parts of epoxy resin polymer.

[0169] The preparation process is as follows:

[0170] Step One: Pour the polyurethane, modified curing agent, and epoxy resin polymer into the mold after melting, heat the mold to 45°C, and naturally foam the material in the mold to form the polishing pad body 1. The polishing pad uses epoxy resin as the base material, which has mechanical properties and corrosion resistance.

[0171] Step Two: Extrude the PVC resin into a ring, and process four different diameter stabilizing rings 3 according to the size of the polishing pad. The evenly distributed four stabilizing rings 3 improve the stability of the working position.

[0172] Step Three: The stabilizing ring 3 is bonded to the formed material by adhesive, and then pressed into the polishing pad body 1. The adhesive is cured again after baking, and then polished and leveled for preliminary installation and preparation.

[0173] Step Four: Heat the SBS toughening material, and make it flow into a strip after melting by heating styrene and butadiene. After cooling, cut the toughening piece 4. The SBS material can flow after heating, making it easy to process and form. After cooling to room temperature, the polystyrene chain segment aggregates into a glassy microzone, which acts as a physical crosslinking point for the polybutadiene chain segment, thereby making the material exhibit rubber properties, improving the toughness, impact strength, bending resistance, and low temperature resistance of the plastic. SBS has good compatibility with polyurethane, which improves the service life of the polishing pad, is conducive to long-term work, and achieves the best working effect. The polishing pad body 1 has elasticity through the toughening piece 4, improving the use effect.

[0174] Step five: the cut toughening piece 4 is installed between the four stabilizing rings 3, the distance between each toughening piece 4 is the same, and the toughening pieces 4 arranged in turn between the four stabilizing rings 3 can still keep stable position in high-speed rotation, thereby improving working precision and prolonging service life;

[0175] Step six: baking and heating the polishing pad body 1, embedding the toughening piece 4 into the polishing pad body 1, and then polishing by a high-precision lathe to obtain a polishing pad with a smooth surface. The polishing pad body 1 is connected by embedding the fixing column 403 into the polishing pad body 1, which facilitates the preparation work.

[0176] In step two, the extrusion ring forming of the PVC resin includes the following steps:

[0177] The PVC resin particles, lubricant, stabilizer, modifier and colorant are mixed and heated;

[0178] After mixing, the screw extruder is used for extrusion;

[0179] In the extrusion molding process, a ring mold is arranged at the terminal, and four different molds are used to prepare four sizes of stabilizing rings 3. The stabilizing ring 3 has heat resistance effect, which improves the working effect.

[0180] In step four, the production process of the toughening piece 4 includes the following steps:

[0181] The plastic toughening composite material is obtained by using melt mixing extrusion with polypropylene and SBS as the main material, calcium carbonate as the filler, and ethylene-vinyl acetate grafted maleic anhydride as the solvent.

[0182] The mechanical properties, flow properties, heat resistance and thermal properties of the composite material are tested and analyzed to observe the influence law of SBS, and a test process is added to improve the product quality of SBS;

[0183] The length-diameter ratio L / D of the screw of the extruder is 24:1, the extrusion melt temperature range is set to 198℃, the feeding section temperature is less than 80℃, and the pressure-resistant piece 402 is obtained by extrusion molding;

[0184] After extrusion molding, three groups of SBS anti-bending strips 401 are adhered to the outside of the pressure-resistant piece 402, and the SBS fixing column 403 is adhered outside. After heating, the toughening piece 4 is obtained. In the production process, the fixing column 403 is embedded in the polishing pad body 1 for connection work. During long-term use, the toughening piece 4 is uniformly stressed by the cooperation of the anti-bending strip 401 and the pressure-resistant piece 402, so as to improve the use effect.

[0185] In step six, the polishing pad polishing process includes the following steps:

[0186] The polishing pad body 1 is placed in the lower mold, heated, and the toughened sheet 4 and the stabilizing ring 3 protruding from the surface of the polishing pad body 1 are polished, the four stabilizing rings 3 are arranged in sequence on the surface of the polishing surface 101, and the polishing head 102 and the polishing surface 101 polish and grind the surface of the crystal;

[0187] The rubber is pasted on the back of the polishing pad body 1, and the shock pad 2 is adhered and connected;

[0188] Grooves and holes are made on the surface of the connected shock pad 2 to complete the forming process.

[0189] The polishing pad prepared in the above examples and comparative examples is placed on the polishing machine, and the silicon wafer containing the silicon oxide layer is polished. The rotation speed of the silicon wafer is 150 rpm, the rotation speed of the platen is 130 rpm, and the grinding speed is 0.2 m / min. The polishing load is 2.1 psi, and the polishing cutting depth is 0.2 mm. After polishing, washing and drying; the film thickness is detected by using a reflectance spectrum film thickness meter, and the polishing efficiency is calculated; at the same time, the number of scratches is observed; the material characteristic coefficient of the silicon wafer is about 148 W / mK; according to the cutting force formula, the grinding cutting force can be calculated by the following formula:

[0190] Fc=k*ap*b*vf

[0191] Wherein, Fc is the grinding cutting force, the unit is N; k is the material characteristic coefficient; ap is the cutting depth, the unit is mm; b is the number of grinding tools; vf is the grinding speed, the unit is m / min.

[0192] The specific data is shown in the following table:

[0193]

[0194] From the above table, it can be seen that under the condition of the same grinding cutting force, the hardness of the polishing pad in example one, example three and example two is lower than that of comparative example one and comparative example two, which shows that the PVC resin and SBS toughening material composition can reduce the hardness of the polishing pad. The wear of example one, example two and example three is less than that of comparative example one and comparative example two, which shows that the PVC resin and SBS toughening material composition can reduce the wear. The number of scratches of example one, example two and example three is less than that of comparative example one and comparative example two, which shows that the PVC resin and SBS toughening material composition can reduce the number of scratches.

[0195] Working principle: the polyurethane, modified curing agent and epoxy resin polymer are heated and melted, then poured into the mold, the mold is heated, the material in the mold is naturally foamed and formed, the polishing pad body 1 is obtained, the polishing pad uses epoxy resin as the base material, has mechanical properties and corrosion resistance, the PVC resin particles, lubricant, stabilizer, modifier and color matching agent are mixed and heated, after mixing, the screw extruder is used for extrusion, the annular mold is arranged at the terminal during the extrusion molding process, four different molds are used to prepare four sizes of stable rings 3, the stable ring 3 has heat resistance effect, improves the working effect, the stable ring 3 is bonded with the formed material through the adhesive, then is pressed into the polishing pad body 1, the adhesive is cured again after baking, and then is polished and flattened, and is quickly installed for preparation, the plastic toughening composite material is obtained by using melt mixing extrusion with polypropylene, SBS as the main material, calcium carbonate as the filler and ethylene-vinyl acetate graft maleic anhydride as the phase solvent, the mechanical properties, flow properties, heat resistance and thermal properties of the composite material are tested and analyzed, the SBS influence law is observed, the test process is added, and the product quality of SBS is improved, the length-diameter ratio L / D of the screw of the extruder is 24:1, the temperature of the feeding section is less than 80℃ after the extrusion melt temperature range setting is completed, the pressure-resistant sheet 402 is obtained by extrusion molding, three groups of SBS bending prevention strips 401 are adhered outside the pressure-resistant sheet 402 after extrusion molding, the SBS fixing column 403 is adhered outside, and the toughening sheet 4 is prepared by heating and adhering and then cooling, in the production work, the fixing column 403 is embedded in the polishing pad body 1 for connection, in the long-term use process, the toughening sheet 4 is uniformly stressed through the cooperation of the bending prevention strip 401 and the pressure-resistant sheet 402, so as to improve the use effect, the cut toughening sheet 4 is installed between the four stable rings 3, the distance between each toughening sheet 4 is the same, and the toughening sheet 4 arranged between the four stable rings 3 can still keep position stable in high-speed rotation, improves the working precision and prolongs the service life, the polishing pad body 1 is placed in the lower mold, heated, and the toughening sheet 4 and the stable ring 3 protruding from the surface of the polishing pad body 1 are polished, the four stable rings 3 are arranged in sequence on the polishing surface 101, the crystal surface is polished and polished by the polishing head 102 and the polishing surface 101, the damping pad 2 is adhered and connected on the back of the polishing pad body 1, grooves and holes are engraved on the surface of the connected damping pad 2, the molding process is completed, and the polishing machine is fixedly connected with the damping pad 2 through the fastening hole 203, in the long-term use process, the toughening sheet 4 is uniformly stressed through the cooperation of the bending prevention strip 401 and the pressure-resistant sheet 402, so as to improve the use effect.

[0196] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting; it is not intended to exclude myriad other embodiments of the present application that other inventors can develop based on the same general inventive concepts embodied by the described embodiments. That is, although the present application is described in terms of particular embodiments and illustrative figures, it should be apparent that the scope of the present application is not limited to these specific embodiments.

[0197] While the embodiments of the application have been shown and described herein, it will be understood by those skilled in the art that many changes, modifications, substitutions and alterations to these embodiments can be made without departing from the principles and spirits of the application, and it is intended that the scope of the application be limited solely by the scope of the appended claims and the equivalents thereof.

Claims

1. A high-grinding-force polishing pad for crystal polishing, comprising a polishing pad body (1), characterized in that: Four stabilizing rings (3) are provided inside the polishing pad body (1), and toughening sheets (4) are installed between the four stabilizing rings (3), and the toughening sheets (4) include anti-bending strips (401), pressure-resistant sheets (402) and fixing columns (403); The stabilizing ring (3) is made of PVC resin; The toughening sheet (4) is a block copolymer prepared by using SBS toughening material.

2. The high-grinding-force polishing pad for crystal polishing according to claim 1, characterized in that: It is prepared from the following components in parts by weight: Polyurethane 100-120 parts; 10-12 parts of modified curing agent; 100-120 parts of epoxy resin polymer; 30-35 parts of PVC resin; 50-60 parts of SBS toughening material.

3. The high-grinding-force polishing pad for crystal polishing according to claim 1, characterized in that: The outer surface of the polishing pad body (1) is provided with an integrally formed polishing surface (101), an integrally formed polishing head (102) is provided in the middle of the polishing surface (101), and four stabilizing rings (3) are arranged in sequence on the surface of the polishing surface (101).

4. The high-grinding-force polishing pad for crystal polishing according to claim 1, characterized in that: A connecting shock-absorbing pad (2) is installed at the lower end of the polishing pad body (1), the connecting shock-absorbing pad (2) is bonded to the polishing pad body (1), an integrally formed positioning groove (201) is provided on the lower end surface of the connecting shock-absorbing pad (2), an integrally formed mounting groove (202) is provided inside the positioning groove (201), a fastening hole (203) is surrounded on the outside of the mounting groove (202), and the fastening hole (203) is used for fixing the shock-absorbing pad (2) and the polishing machine.

5. The high-grinding-force polishing pad for crystal polishing according to claim 1, characterized in that: A plurality of toughening sheets (4) are provided, and the plurality of toughening sheets (4) are fixedly connected to the stabilizing ring (3). The toughening sheets (4) are embedded in the interior of the polishing pad body (1) and fit in contact with the polishing pad body (1).

6. The high-grinding-force polishing pad for crystal polishing according to claim 1, characterized in that: Four anti-bending strips (401) are provided, and the four anti-bending strips (401) are all fixed at the front end of the pressure-resistant sheet (402). The fixing column (403) is used to fix the toughening sheet (4), and the fixing column (403) is embedded in the polishing pad body (1) and fixedly connected to the polishing pad body (1).

7. A process for producing a high-grinding-force polishing pad for crystal polishing according to any one of claims 1 to 6, characterized in that: The steps include: Step 1: Heat and melt the polyurethane, modified curing agent and epoxy resin polymer and then pour them into a mold. The mold is heated to 35-45° C., and the materials in the mold are naturally foamed to form a polishing pad body (1). Step 2: Extruding PVC resin into rings, and processing and forming four stabilizing rings (3) of different diameters according to the size of the polishing pad; Step 3: The stabilizing ring (3) is bonded to the formed material through an adhesive, and then pressed into the polishing pad body (1), and the adhesive is baked again to solidify. After solidification, it is polished and smoothed; Step 4: heating the SBS toughening material, heating styrene and butadiene to melt the material and flow it into strips, and then cutting it into toughened sheets (4) after cooling; Step 5: The cut toughening sheets (4) are installed between the four stabilizing rings (3), and the distance between each toughening sheet (4) is the same; Step 6: Bake and heat the polishing pad body (1), embed the toughening sheet (4) into the polishing pad body (1), and then grind it on a high-precision lathe to obtain a polishing pad with a smooth surface.

8. The production process of a high-grinding-force polishing pad for crystal polishing according to claim 7, characterized in that: In the second step, the extrusion ring forming process of the PVC resin comprises the following steps: Mix and heat the PVC resin pellets, lubricant, stabilizer, modifier and color corrector; After the mixing is completed, the extrusion is carried out through a screw extruder; During the extrusion process, a ring die is set at the terminal, and four sizes of stabilizing rings (3) are prepared through four different dies.

9. The production process of a high-grinding-force polishing pad for crystal polishing according to claim 7, characterized in that: In the step 4, the production process of the toughening sheet (4) includes the following steps: The plastic toughened composite material is prepared by melt mixing and extrusion with polypropylene and SBS as main materials, calcium carbonate as filler, and ethylene-vinyl acetate grafted maleic anhydride as a compatibilizer. By testing and analyzing the mechanical properties, flow properties, heat resistance and thermal properties of composite materials, the influence of SBS was observed; The extruder screw length-to-diameter ratio L / D is 24:1, the extrusion melt temperature range is set to 148-198° C., the feeding section temperature is less than 80° C., and the pressure-resistant sheet (402) is obtained by extrusion molding; After extrusion molding, three sets of SBS anti-bending strips (401) are bonded to the outside of the pressure-resistant sheet (402), and SBS fixing columns (403) are bonded to the outside. The sheet is heated to bond, and then cooled to obtain a toughening sheet (4).

10. The production process of a high-grinding-force polishing pad for crystal polishing according to claim 7, characterized in that: In step 6, the polishing process of the polishing pad includes the following steps: The polishing pad body (1) is placed in a lower mold, heated, and the toughening sheet (4) and the stabilizing ring (3) protruding from the surface of the polishing pad body (1) are polished; Applying glue to the back of the polishing pad body (1) and adhering and connecting the shock-absorbing pad (2); Grooves and holes are punched on the surface of the connecting shock-absorbing pad (2) to complete the forming process.

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