JP2017185557A - Method for manufacturing abrasive pad - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing an abrasive pad by which slicing can be easily performed even if an abrasive pad has a high hardness.SOLUTION: A method for manufacturing an abrasive pad comprises: a process in which a prepolymer and a hardening agent are mixed thereby generating an urethane bond or an urea bond from the prepolymer and the hardening agent; casting process in which a mixture 301 of the prepolymer and the hardening agent is flown into a mold; slicing process in which a block-like product 302 produced in said casting process is sliced; a process in which a sheet-like product 303 produced in said slicing process is maintained in a high temperature state thereby generating a crosslinking reaction; and a process in which after termination of said crosslinking reaction process, the sheet-like product 303 is molded thereby obtaining an abrasive layer 101.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a method for manufacturing a polishing pad used for polishing glass substrates, semiconductor devices, and the like.

  A polishing pad is used for polishing optical materials, semiconductor devices, glass substrates for hard disks, and the like, and particularly preferably used for polishing a device in which an oxide layer or a metal layer is formed on a semiconductor wafer. The polishing pad is made of a synthetic resin such as polyurethane, and has predetermined polishing characteristics depending on the physical properties of the synthetic resin, the distribution of voids formed in the synthetic resin, and the like.

  The polishing pad can be produced by mixing a prepolymer and a curing agent, pouring the mixture into a mold, and slicing the obtained block-shaped molded product with a blade. Here, some polishing pads have a high hardness (for example, those having a Shore D hardness of 55 or more), and when slicing such a polishing pad, there is a risk that the blade will be worn out or the thickness of the polishing pad will be uneven. There is.

  On the other hand, Patent Document 1 describes a method of manufacturing a polishing pad that performs slicing after adjusting the surface hardness of the polyurethane foam block by heating or the like. Patent Document 2 describes a method for manufacturing a polishing pad in which a surface layer portion of a resin block is heated by a heating means and slice processing is performed on the surface layer portion.

JP 2005-169578 A JP 2006-142474 A

  However, in the method described in Patent Document 1, since it is the surface of the polyurethane foam block to be heated, there is a problem that the inside of the block has high hardness and cannot be sliced sufficiently. Moreover, in the method described in Patent Document 2, it is necessary to provide a heating device in the slicing machine, and there is a problem that the manufacturing cost of the polishing pad increases.

  In view of the circumstances as described above, an object of the present invention is to provide a method for manufacturing a polishing pad that can be easily sliced even with a high-hardness polishing pad.

  In order to achieve the above object, a method for producing a polishing pad according to an embodiment of the present invention includes a step of mixing a prepolymer and a curing agent to form a urethane bond or a urea bond by the prepolymer and the curing agent, and the prepolymer. And a casting process for pouring the mixture of the curing agent into the mold, a slicing process for slicing the block-like material generated by the casting process, and a sheet-like material generated by the slicing process are maintained at a high temperature and crosslinked. A step of causing a reaction, and a step of forming the sheet-like material to obtain a polishing layer after completion of the crosslinking reaction step.

  According to this manufacturing method, since the polymer is polymerized by urethane bonds or urea bonds and the block-like material is sliced in a state where the crosslinking reaction is not completed, the hardness of the block-like material at the time of slicing is small. The block-like material can be easily sliced. As a result, it is possible to prevent slicing blades from being worn out and uneven thickness of the sheet-like material.

  In the slicing step, slicing may be performed in a state where the internal temperature of the block-shaped material is 80 ° C. or higher by reaction heat due to generation of the urethane bond or the urea bond.

  In the production method according to the present invention, slicing is performed in a state in which the heat of reaction due to the formation of urethane bonds or urea bonds is accumulated inside the block-shaped material. The internal temperature is preferably 80 ° C. or higher, and more preferably 100 ° C. or higher. In general, polymers used for polishing pads tend to have lower hardness as the temperature rises. By slicing while the heat of reaction due to urethane bonds or urea bonds is accumulated inside, it is easy to block Can be sliced.

  The Shore D hardness of the polishing layer may be 55 or more.

  As described above, in the production method according to the present invention, since the block-like material is sliced in a state where the crosslinking reaction has not progressed, the polishing layer finally produced has a high hardness polishing with a Shore D hardness of 55 or more. Even when the pad is manufactured, the Shore D hardness at the time of slicing is small, and slicing is easy.

  The prepolymer may be an isocyanate compound, and the curing agent may be a polyol curing agent or a polyamine curing agent.

  The isocyanate compound and the polyol curing agent generate a urethane bond and then a crosslinking reaction. Since the crosslinking reaction has a slower reaction rate than the urethane bond formation reaction, the block-like product can be sliced before the crosslinking reaction proceeds. Similarly, an isocyanate compound and a polyamine-based curing agent cause a crosslinking reaction after forming a urea bond. Since the crosslinking reaction has a slower reaction rate than the urea bond formation reaction, the block-like product can be sliced before the crosslinking reaction proceeds.

  In the step of mixing the prepolymer and the curing agent, hollow fine particles having an outer shell made of a thermoplastic resin may be further mixed.

  By further mixing hollow fine particles with the prepolymer and the curing agent, it is possible to form voids by the hollow fine particles in the polishing layer and adjust the polishing characteristics of the polishing layer.

  As described above, according to the present invention, it is possible to provide a method for manufacturing a polishing pad that can be easily sliced even with a high-hardness polishing pad.

1 is a perspective view of a polishing pad according to an embodiment of the present invention. It is sectional drawing of the same polishing pad. It is sectional drawing of the hollow microparticles contained in the polishing layer of the polishing pad. It is a chemical formula of the urethane bond in the polymer which comprises the polishing layer with which the polishing pad is provided. It is a chemical formula of the urea bond in the polymer which comprises the polishing layer with which the polishing pad is provided. It is a chemical formula of the crosslinking reaction in the polymer which comprises the polishing layer with which the polishing pad is provided. It is a flowchart which shows the manufacturing method of the polishing pad. It is a schematic diagram which shows the manufacturing apparatus of the same polishing pad. It is a schematic diagram which shows the block-like thing of the polymer in the manufacturing process of the polishing pad. It is a schematic diagram which shows the block slice method in the manufacturing process of the polishing pad. It is a schematic diagram which shows the block slice method in the manufacturing process of the polishing pad. It is a schematic diagram which shows the sheet-like object in the manufacturing process of the polishing pad. It is a schematic diagram which shows the sheet-like material and adhesive layer in the manufacturing process of the polishing pad. It is a schematic diagram which shows the sheet-like object and adhesive layer which formed the groove | channel in the manufacturing process of the polishing pad. It is a schematic diagram which shows the sheet-like thing, adhesive layer, and cushion layer in the manufacturing process of the polishing pad. It is a flowchart which shows the manufacturing method of the polishing pad which concerns on the comparative example of this invention. It is a schematic diagram which shows the measuring method of the internal temperature of a block-shaped thing in the manufacturing method of the polishing pad which concerns on embodiment of this invention.

  A polishing pad according to an embodiment of the present invention will be described.

[Configuration of polishing pad]
FIG. 1 is a perspective view showing a polishing pad 100 according to this embodiment. As shown in the figure, the polishing pad 100 includes a polishing layer 101, an adhesive layer 102, and a cushion layer 103.

  The polishing layer 101 is a layer that contacts the object to be polished and performs polishing. Hereinafter, the surface of the polishing layer 101 is referred to as a polishing surface 101a. A groove 101b for improving the flow of the slurry liquid is formed on the polishing surface 101a. Note that the groove 101b is not necessarily provided.

  The adhesive layer 102 is a layer that adheres the polishing layer 101 and the cushion layer 103, and is, for example, an adhesive tape.

  The cushion layer 103 is a layer that makes the contact of the polishing layer 101 with the object to be polished uniform. The cushion layer 103 can be made of a flexible material such as a nonwoven fabric or a synthetic resin.

  The polishing pad 100 is attached to the polishing apparatus with an adhesive tape or the like disposed on the cushion layer 103. The size (diameter) of the polishing pad 100 can be determined according to the size of the polishing apparatus and the like, and can be, for example, about 10 cm to 1 m in diameter. The shape of the polishing pad 100 is not limited to a disk shape, and may be a belt shape or the like.

  The polishing pad 100 is rotationally driven while being pressed against the object to be polished by the polishing apparatus, and polishes the object to be polished. At that time, a slurry liquid is supplied between the polishing pad 100 and the object to be polished. The slurry liquid is supplied to the polishing surface 101a via the groove 101b and discharged.

[Configuration of polishing layer]
FIG. 2 is a schematic cross-sectional view of the polishing pad 100. As shown in the figure, the polishing layer 101 includes a polymer 110 and bubbles 111. The bubbles 111 are not necessarily provided. In addition, illustration of the groove | channel 101b is abbreviate | omitted in FIG.

  The polymer 110 is a main constituent material of the abrasive material. The polymer 110 may be a polymer formed by a polymerization reaction between a prepolymer and a curing agent. Examples of such a polymer include polyurethane. Polyurethane is suitable as the polymer 110 because it has good availability and processability and has suitable polishing properties.

  The prepolymer can be a compound having an isocyanate group terminal (hereinafter referred to as an isocyanate compound), which is a compound obtained by reacting a polyisocyanate compound and a polyol compound under conditions usually used, and a polyurethane bond and an isocyanate. A group is included in the molecule. Moreover, the other component may be contained in the polyurethane bond containing isocyanate compound within the range which does not impair the effect of this invention.

  The polyisocyanate compound means a compound having two or more isocyanate groups in the molecule, and for example, diphenylmethane diisocyate can be used.

  In addition, as the polyisocyanate compound, m-phenylene diisocyanate, p-phenylene diisocyanate, 2,6-tolylene diisocyanate (2,6-TDI), 2,4-tolylene diisocyanate (2,4-TDI), Naphthalene-1,4-diisocyanate, diphenylmethane-4,4′-diisocyanate, 3,3′-dimethoxy-4,4′-biphenyl diisocyanate, 3,3′-dimethyldiphenylmethane-4,4′-diisocyanate, xylylene-1 , 4-diisocyanate, 4,4'-diphenylpropane diisocyanate, trimethylene diisocyanate, hexamethylene diisocyanate (HDI), isophorone diisocyanate, propylene-1,2-diisocyanate, butylene-1,2-diisocyanate Cyclohexylene-1,2-diisocyanate, cyclohexylene-1,4-diisocyanate, dicyclohexylmethane-4,4′-diisocyanate (hydrogenated MDI), p-phenylene diisothiocyanate, xylylene-1,4-diiso Examples include thiocyanate and ethylidin diisothiocyanate. These 1 type (s) or 2 or more types can be used.

  The polyol compound means a compound having two or more alcoholic hydroxyl groups (OH) in the molecule. For example, poly (oxytetramethylene) glycol (or polytetramethylene ether glycol) (PTMG) or diethylene glycol ( DEG) can be used.

  Other polyol compounds include diol compounds such as ethylene glycol and butylene glycol, triol compounds, etc .; polyether polyol compounds such as the above-mentioned PTMG; reaction products of ethylene glycol and adipic acid and reactions of butylene glycol and adipic acid Polyester polyol compounds such as products; polycarbonate polyol compounds, polycaprolactone polyol compounds and the like. These 1 type (s) or 2 or more types can be used.

  As the curing agent, a polyamine curing agent can be used. The polyamine-based curing agent is a substance having two or more amino groups, and MOCA (3,3-dichloro-4,4-diaminodiphenylmethane) can be used. In addition, multimeric MOCA containing a trimer in which trimolecular chloroanilines are bonded via a methylene group can be used as a polyamine-based curing agent. Moreover, you may utilize polyamine type hardening | curing agents other than MOCA.

  Moreover, a polyol type hardening | curing agent can also be utilized for a hardening | curing agent. The polyol curing agent is a substance having two or more hydroxyl groups, and can be, for example, ethylene glycol or polyether polyol.

  In addition, as a polyol-based curing agent, a low molecular weight polyol compound such as butylene glycol and hexanediol, and a reaction product of polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol (PTMG), bisphenol A and propylene oxide. Polyether polyol compounds such as, a reaction product of ethylene glycol and adipic acid, a polyester polyol compound such as a reaction product of butylene glycol and adipic acid, a high molecular weight polyol compound such as a polycarbonate polyol compound and a polycaprolactone polyol compound. .

  As the curing agent, one or more of the polyamine curing agent and the polyol curing agent can be used.

  Here, each component is mixed so that R value which is an equivalent ratio of the amino group or hydroxyl group present in the curing agent to the isocyanate group present at the end of the prepolymer is 0.70 to 1.20. . The R value is preferably 0.70 to 1.20, more preferably 0.80 to 1.00, and still more preferably 0.85 to 0.95. By setting the R value to 1 or less, the excess isocyanate group is used for the crosslinking reaction described later.

  The polishing layer 101 of the polishing pad 100 of the present invention is composed of a polyurethane resin produced by the reaction of the prepolymer and the curing agent. This polyurethane resin may be in a non-foamed state or in a foamed state (foam). But you can. As a foaming method, any of foaming using hollow fine particles, chemical foaming, and mechanical foaming generally employed in the industry can be employed. FIG. 2 illustrates foaming using hollow fine particles.

  The hollow fine particles 111 are hollow spherical objects and are contained in the polymer 110. FIG. 3 is a schematic cross-sectional view of the hollow fine particles 111. As shown in the figure, the hollow fine particles 111 have a spherical outer shell 111a made of a thermoplastic resin, and an inner space 111b surrounded by the outer shell 111a. The hollow fine particles 111 can be formed by wrapping a liquid low-boiling point hydrocarbon in a thermoplastic resin shell and heating.

  The thermoplastic resin is softened by heating, the low-boiling hydrocarbon is changed to a gas, and the thermoplastic resin is expanded by the pressure of the gas, whereby the hollow fine particles 111 are formed. For example, isobutane or pentane is used as the low boiling point hydrocarbon, and vinylidene chloride or acrylonitrile is used as the thermoplastic resin.

  As the hollow fine particles 111, commercially available products can be used. For example, the Matsumoto Microsphere series (manufactured by Matsumoto Yushi Seiyaku Co., Ltd.) and the Expandcell series (manufactured by Akzo Nobel) can be used as the hollow fine particles 111.

  The size of the hollow fine particles 111 is not particularly limited, but may be about 20 μm to 200 μm in diameter, and two or more types of hollow fine particles having different diameters may be used. The content ratio of the hollow fine particles 111 in the polishing material is preferably 10 to 60% by volume and more preferably 15 to 45% by volume with respect to the polishing material. When the polishing layer 101 is worn by polishing, the hollow fine particles 111 are exposed to the polishing surface 101a and affect the polishing characteristics of the polishing surface 101a.

  In addition to foaming using the exemplified hollow fine particles, chemical foaming, mechanical foaming, and the like are conceivable. Examples of chemical foaming include a method of generating carbon dioxide from an isocyanate compound by adding water. . Examples of the mechanical foaming include a method in which an inert gas such as air, nitrogen, oxygen, carbon dioxide, helium, and argon is mechanically stirred and mixed into the foam curable composition. As other foaming methods, foam stabilizers, catalysts, and the like that are commonly used in the art may be added to the foamable composition. Examples of the foam stabilizer include a surfactant, and more specifically include, for example, a polyether-modified silicone. Any catalyst commonly used in the art can be used in the present invention.

  The polishing layer 101 may be composed of only the polymer 110 without including the hollow fine particles 111.

[Reaction between prepolymer and curing agent]
As described above, the polishing layer 101 includes the polymer 110 formed by the reaction of the prepolymer and the curing agent. 4 to 6 are chemical formulas showing the reaction between the prepolymer and the curing agent.

  When a prepolymer that is an isocyanate compound and a polyol-based curing agent are mixed, first, polymerization by urethane bonds shown in FIG. 4 occurs. ˜NCO is an isocyanate group possessed by an isocyanate compound, and ˜OH is a hydroxyl group possessed by a polyol curing agent. This reaction has a high reaction rate and is an exothermic reaction. By this reaction, the polymer is cured to obtain a block-like product.

  After the polymerization reaction due to the urethane bond is almost finished, the crosslinking reaction shown in FIG. 6 proceeds. ˜NHCOO˜ is a urethane bond existing in the isocyanate compound molecule or a urethane bond generated by the reaction of the isocyanate compound and the polyol compound, and ˜NCO is an excess isocyanate group possessed by the isocyanate compound. This cross-linking reaction is a reaction having a slower reaction rate than the polymerization reaction by urethane bonds. As this reaction proceeds, the polymer forms a crosslinked structure and the hardness increases.

When a prepolymer that is an isocyanate compound and a polyamine-based curing agent are mixed, first, polymerization by a urea bond shown in FIG. 5 occurs. ˜NCO is an isocyanate group possessed by an isocyanate compound, and ˜NH ₂ is an amino group possessed by a polyamine curing agent. This reaction has a high reaction rate and is an exothermic reaction. By this reaction, the polymer is cured and a block-like product is obtained.

  After the polymerization reaction by the urea bond is almost finished, the crosslinking reaction shown in FIG. 6 proceeds. ˜NHCOO˜ is a urethane bond present in the isocyanate compound molecule, and ˜NCO is an excess isocyanate group of the isocyanate compound. This cross-linking reaction is a reaction having a slower reaction rate than the polymerization reaction by urea bonds. As this reaction proceeds, the polymer forms a crosslinked structure and the hardness increases.

  When a prepolymer that is an isocyanate compound, a polyol-based curing agent, and a polyamine-based curing agent are mixed, after the urethane bond shown in FIG. 4 and the urea bond shown in FIG. 5 are formed, the crosslinking reaction shown in FIG. 6 proceeds.

  The polymer 110 can be a polymer formed by reacting a prepolymer that is an isocyanate compound with one or both of a polyol-based curing agent and a polyamine-based curing agent.

[Production method of polishing pad]
A method for manufacturing the polishing pad 100 will be described. FIG. 7 is a flowchart showing a manufacturing method of the polishing pad 100, and FIG. 8 is a schematic diagram of a manufacturing apparatus 200 used for manufacturing the polishing pad 100. The manufacturing apparatus 200 includes a first storage tank 201, a second storage tank 202, a stirring tank 203, and a mold 204.

  First, a prepolymer is charged into the first storage tank 201, and a foaming agent is charged as necessary. The prepolymer is the above-described isocyanate compound. Instead of the foaming agent, the hollow fine particles described above may be introduced. The inside of the first storage tank 201 is depressurized and degassed, and pressurized with an inert gas.

  Further, a curing agent is put into the second storage tank 202. The curing agent is one or both of the polyol-based curing agent and the polyamine-based curing agent described above. The second storage tank 202 is heated to melt the curing agent.

  The contents of the first storage tank 201 (hereinafter, the first solution) are sent from the first storage tank 201 to the stirring tank 203, and the contents (hereinafter, the second solution) of the second storage tank 202 are transferred from the second storage tank 202 to the stirring tank 203. To send. At the same time, the first solution and the second solution are mixed in the stirring tank 203 (St101). At the same time as the mixing is started, a polymerization reaction by a urethane bond (FIG. 4) or a urea bond (FIG. 5) is started.

  Subsequently, a fluid mixture 301 containing a prepolymer and a curing agent is poured into a mold 204 to perform casting (St102). The mold 204 may be heated. As the polymerization reaction proceeds, the mixture 301 is cured, and a block-like product made of a polymer is formed. FIG. 9 is a schematic diagram of the block-like object 302 generated by the casting process. The size of the block-shaped object 302 is, for example, 80 cm × 80 cm, and the thickness is, for example, 40 mm.

  The time variation of the internal temperature of the block-like object 302 during the casting process is shown in [Table 1] below. FIG. 17 is a schematic diagram showing a method for measuring the internal temperature. The internal temperature of the block 302 is shown in FIG. 17, and thermocouples T are provided on the top (location 10 mm from the top) and the bottom (location 30 mm from the top) of the block 302, and the internal temperature immediately after casting The temperature was measured. As can be seen from [Table 1], it can be seen that the internal temperature rises due to the heat of reaction accompanying the formation of urethane bonds or urea bonds immediately after the start of casting, and then gradually decreases.

  Subsequently, the block-like object 302 is sliced (St103). FIGS. 10 and 11 are schematic views of slices. As shown in these drawings, the block-shaped object 302 is fixed by the suction surface plate 205, the blade 206 is moved with respect to the block-shaped object 302, and the block-shaped object 302 is sliced. Note that the blade 206 may be fixed, and the block 302 and the suction surface plate 205 may be moved with respect to the blade 206.

  It is preferable that the slicing is performed in a state where heat generated by a polymerization reaction by urethane bond or urea bond is stored in the block-shaped object 302 and the internal temperature of the block-shaped object 302 is 80 ° C. or higher. Specifically, as shown in Table 1, slicing is preferably performed within 30 minutes after the start of casting. When slicing is performed after 30 minutes have elapsed, the crosslinking reaction proceeds with a decrease in the internal temperature, so that the hardness of the block-like object 302 is increased and the slicing may not be performed well. A sheet-like object is formed from the block-like object 302 by this slicing. FIG. 12 is a schematic diagram of the sheet-like material 303. The sheet-like object 303 has a thickness of 1 mm, for example, and about 20 sheet-like objects 303 can be formed from the block-like object 302.

  Subsequently, the sheet-like material 303 is accommodated in a dryer, and heated and dried (St104). By this heating / drying step, the above-described crosslinking reaction (FIG. 6) proceeds, and the polymer constituting the sheet-like material 303 is further cured. The heating / drying step is performed, for example, at 120 ° C. for several hours to several days until the sheet-like material has a desired hardness. The Shore D hardness of the sheet-like material 303 at the completion of the heating / drying process is, for example, 55 or more at room temperature (25 ° C.).

  Subsequently, an adhesive layer is laminated on the sheet-like material 303 (St105). FIG. 13 is a schematic diagram showing the sheet-like material 303 and the adhesive layer 304. The adhesive layer 304 can be laminated by sticking an adhesive tape to the sheet-like material 303, for example.

  Subsequently, a groove is formed in the sheet-like material 303 (St106). FIG. 14 is a schematic diagram showing the sheet-like object 303 and the adhesive layer 304 in which the groove 303a is formed. Note that the step of forming the groove 303a may be omitted.

  Subsequently, a cushion layer is laminated on the adhesive layer 304 (St107). FIG. 15 is a schematic diagram showing the sheet-like object 303, the adhesive layer 304, and the cushion layer 305. The cushion layer 305 can be laminated by sticking to the adhesive layer 304.

  Subsequently, the laminate of the sheet-like material 303, the adhesive layer 304, and the cushion layer 305 is cut (St108). By this cutting, the laminate is formed into a predetermined shape, and the polishing pad 100 (FIG. 1) is formed. The sheet-like material 303 corresponds to the polishing layer 101, the adhesive layer 304 corresponds to the adhesive layer 102, and the cushion layer 305 corresponds to the cushion layer 103. It should be noted that the steps St105 to 108 after the crosslinking reaction has not necessarily been performed in this order.

[Effect]
The effect of the present invention will be described after comparison with a comparative example which is a conventionally known manufacturing method. FIG. 16 is a flowchart showing a manufacturing method according to a comparative example. In the manufacturing method according to the comparative example, the first solution and the second solution are mixed (St201) and cast (St202). Thereby, a urethane bond (FIG. 4) or a urea bond (FIG. 5) is formed. Subsequently, the block-like material formed by casting is heated and dried with a dryer (St203).

  Thereby, a crosslinking reaction (FIG. 7) advances and the polymer which comprises a block-shaped thing hardens | cures. The heating / drying process is continued until the block-like material has a desired hardness. Subsequently, the block-like object is sliced (St204) to form a sheet-like object.

  Subsequently, an adhesive layer is laminated (St205), and a groove is formed (St206). Further, a cushion layer is laminated (St207) and cut into a desired shape (St208), thereby generating a polishing pad.

  In the manufacturing method according to the comparative example, as described above, the block-like material is sliced after the heating / drying step. At this time, since the cross-linking reaction of the polymer constituting the block-like product proceeds as described above, and the block-like product has a certain hardness, the block-like product has a high hardness (Shore D hardness 55 or more). Since the hardness of the block-like material is large, the relative movement with respect to the blade in the slicing process is impossible, the blade used for slicing is worn out, or the thickness of the sheet-like material is uneven.

  On the other hand, in the manufacturing method (FIG. 7) according to the present embodiment, since the slice (St103) is performed before the heating / drying step (St104), that is, before the crosslinking reaction is completed, the hardness of the block-shaped product is small. Can be sliced. Thereby, it is possible to prevent the blade used for slicing from being worn and to make the thickness of the sheet-like material uniform.

  Moreover, in the manufacturing method according to the present embodiment, a step of heating the block-like object is not required in order to reduce the hardness, and the manufacturing cost can be reduced. The manufacturing method according to the present embodiment is suitable for a polishing pad having a high hardness of the polishing layer 101, and particularly suitable for a high-hardness polishing pad having a Shore D hardness of 55 or more.

DESCRIPTION OF SYMBOLS 100 ... Polishing pad 101 ... Polishing layer 102 ... Adhesive layer 103 ... Cushion layer 110 ... Polymer 111 ... Hollow fine particle 301 ... Mixture 302 ... Block-shaped thing 303 ... Sheet-like thing

Claims (5)

Mixing the prepolymer and the curing agent to form urethane bonds or urea bonds by the prepolymer and the curing agent;
A casting step of pouring the mixture of the prepolymer and the curing agent into a mold;
A slicing step of slicing the block-like material generated by the casting step;
Maintaining the sheet-like material produced by the slicing step in a high temperature state and causing a crosslinking reaction;
A method for producing a polishing pad comprising: a step of forming the sheet-like material to obtain a polishing layer after completion of the crosslinking reaction step. It is a manufacturing method of the polishing pad according to claim 1,
In the slicing step, the polishing pad is manufactured by slicing in a state where the internal temperature of the block-shaped material is 80 ° C. or higher by reaction heat due to the generation of the urethane bond or the urea bond. It is a manufacturing method of the polishing pad according to claim 1,
The method for producing a polishing pad, wherein the Shore D hardness of the polishing layer is 55 or more. It is a manufacturing method of the polishing pad according to claim 1,
The prepolymer is an isocyanate compound;
The said hardening | curing agent is a polyol type hardening | curing agent or a polyamine type hardening | curing agent. The manufacturing method of a polishing pad. It is a manufacturing method of the polishing pad according to claim 1,
In the step of mixing the prepolymer and the curing agent, a hollow fine particle having an outer shell made of a thermoplastic resin is further mixed.

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