Abrasive pad and method of manufacturing the same

Abstract

This invention relates to abrasive pads and methods for manufacturing the same. The aim is to provide abrasive pads with high design freedom and methods for manufacturing the same. The abrasive pad includes an abrasive layer, wherein the abrasive layer has an abrasive surface and a back surface opposite to the abrasive surface, a protrusion on the abrasive surface side, and a recess corresponding to the protrusion on the back surface side. The abrasive pad includes a filler filling the recesses of the abrasive layer, the filler comprising resin.

Description

Technical Field

[0001] This invention relates to abrasive pads and methods for manufacturing the same. Background Technology

[0002] Typically, polishing processes using polishing pads are performed on optical materials such as lenses, parallel planar plates and mirrors, semiconductor wafers, semiconductor devices, hard disk substrates, metals, and ceramics. Various types of polishing pads are known, including those using non-woven fabric, those using foamed or non-foamed polyurethane, those with fixed abrasive grains, and those using a resin layer with a raised or recessed pattern as the polishing surface.

[0003] Among them, abrasive pads with a raised or recessed abrasive layer have the following advantages: the grooves forming the raised or recessed pattern affect the flowability of the slurry, thereby increasing the grinding speed and uniformly grinding the workpiece. Methods for manufacturing such abrasive pads include, for example: forming grooves by cutting the surface of a flat substrate; forming the raised or recessed pattern on a substrate using screen printing; and manufacturing a mold with the raised or recessed pattern and molding it using the mold.

[0004] For example, Patent Document 1 discloses an abrasive pad with an embossed pattern formed by transferring the pattern from a printing plate having an embossed pattern formed of photosensitive resin. Patent Document 2 discloses an abrasive pad with an embossed pattern formed using a molding die made of silicone rubber or the like after transferring the embossed pattern from a printing plate having an embossed pattern formed of photosensitive resin.

[0005] Existing technical documents Patent documents Patent Document 1: Japanese Patent Application Publication No. 2019-178248 Patent Document 2: Japanese Patent Application Publication No. 2019-178258 Summary of the Invention

[0006] The problem that the invention aims to solve Various types of abrasive pads have been developed, exemplified by Patent Document 1, but there is still a desire to increase the freedom of design.

[0007] The present invention was made in view of the above-mentioned problems, and its purpose is to provide an abrasive pad with high design freedom and a method for manufacturing the same.

[0008] Methods for solving problems The inventors of this application conducted in-depth research to solve the above-mentioned problems and found that the above-mentioned problems could be solved by using an abrasive pad with a specified structure and a method for manufacturing the same, thus completing the present invention.

[0009] That is, the present invention is as follows. [1] Abrasive pads are abrasive pads with abrasive layers. The polishing layer has a polishing surface and a back surface opposite to the polishing surface. A protrusion is located on the polishing surface side, and a recess corresponding to the protrusion is located on the back surface side. The abrasive pad has a filler that fills the recesses of the abrasive layer. The filler contains resin. [2] The abrasive pad as described in [1], wherein, There are gaps on the back side of the recess where the filling material is not present. [3] The abrasive pad as described in [1], wherein, There is a covering portion on the back side that at least covers the recess. [4] The abrasive pads described in [1] to [3], wherein, The abrasive layer comprises a coating having the abrasive surface. [5] A method for manufacturing an abrasive pad, specifically a method for manufacturing an abrasive pad having an abrasive layer, the method comprising: The process of forming a protrusion on one side of the film and forming a concave portion on the opposite side of the film corresponding to the protrusion to obtain the polishing layer; The process of filling the recess with a material comprising a curable resin; and The process of curing the curable resin to form a filler. [6] The method for manufacturing the abrasive pad as described in [5], wherein, After the process of forming the filler, there are gaps in the recess where the filler is not present. [7] The method of manufacturing an abrasive pad as described in [5] or [6] further includes a step of laminating a coating layer on the surface of the abrasive layer having the protrusion.

[0017] Invention Effects According to the present invention, it is possible to provide an abrasive pad with a high degree of design freedom. Attached Figure Description

[0018] Figure 1 A cross-sectional view is shown to schematically illustrate an example of the configuration of the abrasive pad in this embodiment.

[0019] Figure 2AA cross-sectional view is shown to schematically illustrate another configuration example of the abrasive pad of this embodiment.

[0020] Figure 2B A cross-sectional view is shown to schematically illustrate another configuration example of the abrasive pad of this embodiment.

[0021] Figure 2C A cross-sectional view is shown to schematically illustrate another configuration example of the abrasive pad of this embodiment.

[0022] Figure 2D A cross-sectional view is shown to schematically illustrate another configuration example of the abrasive pad of this embodiment.

[0023] Figure 3 A cross-sectional view is shown to schematically illustrate another configuration example of the abrasive pad of this embodiment.

[0024] Figure 4 This is a flowchart illustrating an example of a method for manufacturing an abrasive pad according to this embodiment.

[0025] Figure 5 This is a schematic diagram illustrating step S1 in an example of the method for manufacturing the polishing pad according to this embodiment.

[0026] Figure 6 This is a schematic diagram illustrating step S1 in an example of the method for manufacturing the polishing pad according to this embodiment.

[0027] Figure 7 This is a schematic diagram illustrating step S2 in an example of the method for manufacturing the polishing pad according to this embodiment.

[0028] Figure 8 This is a schematic diagram illustrating step S3 in an example of the method for manufacturing the polishing pad according to this embodiment.

[0029] Explanation of reference numerals in the attached figures 10, 200, 210, 220, 230, 300… Abrasive pad; 11… Abrasive layer; 111… Abrasive surface; 112… Back side; 113… Protrusion; 114… Recess; 12… Filler; 13… Void; 20… Cover; 30… Coating; 40… Film; 50… Resin composition; 60… Light source; L… Ultraviolet light. Detailed Implementation

[0030] Hereinafter, embodiments of the present invention (hereinafter referred to as "this embodiment") will be described in detail, but the present invention is not limited thereto and various modifications can be made without departing from its spirit. It should be noted that in the accompanying drawings, the same reference numerals are used for the same elements, and repeated descriptions are omitted. Furthermore, unless otherwise stated, positional relationships such as up, down, left, and right are based on the positional relationships shown in the accompanying drawings. In addition, the scale of the accompanying drawings is not limited to the scale shown.

[0031] 1. Grinding pad The abrasive pad of this embodiment includes an abrasive layer, which has an abrasive surface and a back surface opposite to the abrasive surface. The abrasive surface side has a protrusion, and the back surface side has a recess corresponding to the protrusion. The abrasive pad may include a filler filling the recesses of the abrasive layer; the filler may also contain resin.

[0032] Figure 1 A schematic cross-sectional view of the abrasive pad according to this embodiment is shown in the figure. Figure 1 As shown, the polishing pad 10 includes a polishing layer 11, which has a polishing surface 111 and a back surface 112 opposite to the polishing surface. The polishing layer 11 has a protrusion 113 and a flat portion 115 without the protrusion 113 on the polishing surface 111 side. The polishing layer 11 has a recess 114 corresponding to the protrusion 113 on the back surface 112 side. Figure 1 As shown, the abrasive pad 10 may also have a filler 12 that fills the recess 114 of the abrasive layer 11, and the filler 12 may also contain resin.

[0033] For the abrasive pad 10 of this embodiment, since different materials can be used for the filler 12 and the abrasive layer 11 in the molding of the concave-convex pattern of the abrasive layer 11, the design freedom is high. In addition, the abrasive pad of this embodiment can improve the abrasive speed and reduce the surface roughness of the workpiece after abrasion.

[0034] Hereinafter, the components of the abrasive pad 10 of this embodiment will be described in detail.

[0035] 1.1. Abrasive Layer The abrasive layer 11 has an abrasive surface 111 and a back surface 112 opposite to the abrasive surface. The abrasive layer 11 has a protrusion 113 on the abrasive surface 111 side and a recess 114 corresponding to the protrusion 113 on the back surface 112 side. The abrasive surface 111 is the side on which the workpiece is abraded.

[0036] The material constituting the abrasive layer 11 is not particularly limited, and resins are an example. The resin is not particularly limited, and examples include thermoplastic resins such as polyethylene, polypropylene, polyvinyl chloride, polystyrene, ABS resin, acrylic resin, polycarbonate, polyamide, and polyester resin; thermosetting resins such as phenolic resin, epoxy resin, acrylic resin, urethane resin, and formaldehyde resin; and photocurable resins such as isocyanurate resins, acrylic (methacrylic) ester resins and their urethane-modified resins, and Thiokol resins. The abrasive layer may contain one type of resin alone or two or more types in combination. In addition to the above, the abrasive layer may also contain optional components such as polymerization initiators and curing agents.

[0037] 1.1.1.Protrusion The grinding layer 11 has protrusions 113. By having protrusions 113 and flat portions 115 on the grinding surface 111, liquid components such as coolant used during grinding can be supplied to or discharged from the grinding surface 111, and grinding debris can be efficiently discharged. The protrusions 113 are preferably arranged in a regular pattern when viewed from above. By arranging the protrusions 113 in a regular pattern, more homogeneous grinding can be performed, and a grinding with a superior surface finish can be achieved. It should be noted that "viewed from above" means viewed from below in each figure. Furthermore, "regular pattern" refers to an arrangement pattern obtained by regularly arranging multiple protrusions 113 as units.

[0038] The arrangement pattern of the protrusions 113 on the grinding surface 111 is not particularly limited as long as it is an arrangement pattern having both protrusions 113 and flat portions 115. Among these, an arrangement pattern having multiple dot-shaped protrusions 113 is preferred. Examples of the arrangement pattern of the multiple protrusions 113 include: an arrangement pattern in which the multiple protrusions 113 are arranged in a concentric circle when viewed from above; an arrangement pattern in which the multiple protrusions 113 are arranged in a grid-like manner when viewed from above; an arrangement pattern in which the multiple protrusions 113 are arranged radially when viewed from above; an arrangement pattern in which the multiple protrusions 113 are arranged spirally when viewed from above; and an arrangement pattern formed by combining these.

[0039] It should be noted that the three-dimensional shape of the dots in the case of the dotted protrusions 113 pattern is not particularly limited. Examples include hemispherical, approximately hemispherical, spherical cap-shaped, approximately spherical cap-shaped, spherical band-shaped, approximately spherical band-shaped, semi-ellipsoidal, approximately semi-ellipsoidal, cylindrical (e.g., cylindrical, approximately cylindrical, elliptical cylindrical, approximately elliptical cylindrical, and polygonal prism), and truncated cone (e.g., truncated cone, approximately truncated cone, truncated elliptical cone, approximately truncated elliptical cone, and truncated polygonal cone). Among the above, the truncated cone shape can be a truncated cone shape extending from the back side towards the grinding surface side, or a truncated cone shape extending from the grinding surface side towards the back side side.

[0040] Regarding the height of the protrusion 113, from the viewpoint of more effectively and reliably achieving the aforementioned effects, it is preferably 0.01 mm to 10 mm, more preferably 0.1 mm to 5 mm, and even more preferably 0.3 mm to 3 mm. By ensuring the height of the protrusion 113 is within the aforementioned range, there is a tendency to further improve the discharge of grinding debris and further reduce the surface roughness of the workpiece. Furthermore, regarding the height of the protrusion 113, it is preferable that at least one of the plurality of protrusions 113 is within the aforementioned range, more preferably that the average height of the plurality of protrusions 113 is within the aforementioned range, and even more preferably that all of the plurality of protrusions 113 are within the aforementioned range.

[0041] From the viewpoint of more effectively and reliably achieving the aforementioned effect, the area of ​​the protrusion 113 when viewed from above is preferably 0.1 mm. 2 Above 100mm 2 The following is more preferably 1mm 2 Above 50mm 2 Hereinafter, 3mm is further preferred. 2 The above 25mm 2 The following applies. By ensuring that the area of ​​the protrusion 113 in plan view is within the aforementioned range, there is a tendency to further improve the removal of grinding debris and further reduce the surface roughness of the workpiece. Furthermore, regarding the area of ​​the protrusion 113 in plan view, it is preferable that at least one of the plurality of protrusions 113 is within the aforementioned range; more preferably, it is preferable that the average area of ​​the plurality of protrusions 113 in plan view is within the aforementioned range; and even more preferably, it is preferable that all of the plurality of protrusions 113 are within the aforementioned range. It should be noted that the area of ​​the protrusion 113 in plan view is the largest of the cross-sectional areas when the protrusion 113 is cut at any height along a plane parallel to the grinding surface.

[0042] From the viewpoint of more effectively and reliably achieving the aforementioned effects, the spacing width of the protrusions 113 (the width of the flat portion 115) is preferably 0.1 mm to 10 mm or less, more preferably 0.1 mm to 5 mm or less, and even more preferably 0.3 mm to 3 mm or less. By ensuring the spacing width of the protrusions 113 is within the aforementioned range, there is a tendency to further improve the removal of grinding debris and further reduce the surface roughness of the workpiece being ground. Here, "spacing width" refers to the shortest distance between two protrusions 113. Furthermore, regarding the spacing width of the protrusions 113, it is preferable that at least one of the spacings of the plurality of protrusions 113 is within the aforementioned range, more preferably that the average spacing width between the plurality of protrusions 113 is within the aforementioned range, and even more preferably that all of the spacing widths between the plurality of protrusions 113 are within the aforementioned range.

[0043] 1.1.2.Concave part The polishing layer 11 has recesses 114. The recesses 114 may also be filled with filler 12. The recesses 114 may also be formed simultaneously on the back surface 112 when the protrusions 113 are formed. The arrangement pattern of the recesses 114 can be the same as the arrangement pattern of the protrusions 113. The three-dimensional shape of the space defined by the recesses 114 can be the same as the three-dimensional shape of the dotted protrusions 113.

[0044] From the viewpoint of more effectively and reliably achieving the aforementioned effects, the depth of the recess 114 is preferably 0.01 mm to 10 mm, more preferably 0.1 mm to 5 mm, and even more preferably 0.3 mm to 3 mm. By ensuring the depth of the recess 114 is within the aforementioned range, there is a tendency to further improve the removal of grinding debris and further reduce the surface roughness of the workpiece. Furthermore, regarding the depth of the recess 114, it is preferable that at least one of the plurality of recesses 114 is within the aforementioned range, more preferably that the average depth of the plurality of recesses 114 is within the aforementioned range, and even more preferably that all of the plurality of recesses 114 are within the aforementioned range.

[0045] From the viewpoint of more effectively and reliably achieving the aforementioned effect, the area of ​​the recess 114 as viewed from top view is preferably 0.1 mm. 2 Above 100mm 2 The following is more preferably 1mm 2 Above 50mm 2 Hereinafter, 3mm is further preferred. 2 The above 25mm 2 The following applies. By ensuring that the area of ​​the recess 114 as viewed from above is within the aforementioned range, there is a tendency to further improve the removal of grinding debris and further reduce the surface roughness of the workpiece. Furthermore, regarding the area of ​​the recess 114 as viewed from above, it is preferable that at least one of the plurality of recesses 114 is within the aforementioned range; more preferably, it is preferable that the average area of ​​the plurality of recesses 114 as viewed from above is within the aforementioned range; and even more preferably, it is preferable that all of the plurality of recesses 114 are within the aforementioned range. It should be noted that the area of ​​the recess 114 as viewed from above is the largest cross-sectional area among those obtained by cutting the recess 114 at any depth along a plane parallel to the grinding surface.

[0046] 1.1.2.1. Filler The abrasive pad 10 in this embodiment may also include a filler 12. The filler 12 in this embodiment fills the recess 114 and may contain resin. The filler 12 may be filled in a state containing uncured resin and then cured, or it may be filled in a state containing cured resin. By including the filler 12, the protrusion 113 is strengthened.

[0047] The resin contained in filler 12 is not particularly limited, and examples include thermoplastic resins such as polyethylene, polypropylene, polyvinyl chloride, polystyrene, ABS resin, acrylic resin, polycarbonate, polyamide and polyester resin; thermosetting resins such as phenolic resin, epoxy resin, acrylic resin, urethane resin and formaldehyde resin; and photocurable resins such as isocyanurate resin, acrylic (methacrylic) ester resin and its urethane modified resin, and Thiokol resin.

[0048] The resin contained in filler 12 can also be a different type from the resin forming the abrasive layer. Using such a resin, there is a trend towards further increased design freedom for abrasive pads. The resin contained in filler 12 can be used alone or in combination with two or more types. In addition to the above, filler 12 may also contain optional components such as polymerization initiators and curing agents.

[0049] Relative to the total amount of filler 12, the resin content in filler 12 can be 50% by mass or more, 75% by mass or more, 90% by mass or more, 95% by mass or more, 98% by mass or more, or 100% by mass, meaning that filler 12 is formed solely of resin. Furthermore, the upper limit of the resin content in filler 12 can be 100% by mass, 98% by mass, 95% by mass, or 90% by mass.

[0050] The filler 12 can fill the recess 114 in a way that does not create voids, but it is preferable to fill the recess 114 in a way that creates voids. That is, it is preferable that there are voids without filler 12 within the recess 114. By having voids without filler 12, these voids can provide cushioning, thus further improving the follow-through of the abrasive pad 10 to the workpiece and tending to result in a better surface roughness of the workpiece after abrasion. From the viewpoint of achieving such an effect more effectively and reliably, it is more preferable that the aforementioned voids exist on the back side within the recess 114.

[0051] 1.2. Covering section In this embodiment, the polishing pad may also have a cover portion. Figure 2 shows an example of a polishing pad with a cover portion. The polishing pad 200 shown in Figure 2 may have a cover portion 20 that covers at least a portion of the recess 114, or it may have a cover portion that covers at least the recess 114. By having the polishing pad 200 have such a cover portion 20, it is possible to more effectively prevent the filler 12 from separating from the polishing layer 11. In addition, the cover portion 20 may have cushioning properties during polishing, or it may have adhesive properties to other components. By having such a cover portion 20, there is a tendency to further increase the design freedom, such as allowing the cushioning properties of the polishing pad 200 to be within a more suitable range.

[0052] The cover portion 20 can be sheet-shaped, for example, a sheet-shaped portion of a size capable of covering all of the plurality of recesses 114 of the polishing layer 11. Alternatively, the cover portion 20 can be one or more, and a portion of the plurality of recesses 114. The cover portion 20 can also be multiple independent components.

[0053] The material constituting the cover 20 is not particularly limited, and examples include thermoplastic resins such as acrylic resin, vinyl resin, olefin resin, styrene resin, polyester resin, polycarbonate resin, and polyamide resin. One type of material may be used alone, or two or more types may be used in combination. The cover 20 may also be a nonwoven fabric.

[0054] The cover portion 20 may also contain an adhesive for bonding to the abrasive layer and filler. Alternatively, the cover portion 20 may contain an adhesive for bonding to a grinding platform or the like on a surface opposite to the surface in contact with the abrasive layer 11. Examples of adhesives used in such a cover portion 20 include various thermoplastic adhesives such as acrylic adhesives, nitrile adhesives, nitrile rubber adhesives, polyamide adhesives, polyurethane adhesives, polyester adhesives, and silicone adhesives. One or more of these adhesives may be used individually.

[0055] The cover portion 20 may also be a layered component formed from multiple sheet-like parts. That is, the cover portion 20 may, for example, contain a layer of adhesive for bonding to the polishing layer 11, and a cushioning layer; it may also contain a layer of adhesive for bonding to the polishing platform, etc., and may have a release layer that covers the layer containing the adhesive for bonding to the polishing platform, etc., before bonding to it. Alternatively, the cover portion 20 may also be double-sided tape.

[0056] When the abrasive pad has a cover portion 20, a gap 13 may also be present in the recess 114. Figures 2B to 2D Another example of abrasive pad configuration with a cover portion is shown. Figure 2B The abrasive pad 210 shown has a gap 13 between the filler 12 and the cover 20 (in other words, the back side within the recess 114). Figure 2C The polishing pad 220 shown has a gap 13 between the polishing layer 11 and the filler 12 (in other words, the polishing surface side within the recess 114). Figure 2D The polishing pad 230 shown is not filled with filler 12, and has a gap 13 between the polishing layer 11 and the cover portion 20 described later. Even so Figure 2DAs shown in the abrasive pad 230, even when the recess 114 is not filled with filler, compared to an abrasive pad without a recess, the cushioning can be further precisely controlled by adjusting the size of the gap 13 in the recess 114, thus providing a high degree of design freedom.

[0057] 1.3. Coating In this embodiment, the abrasive pad 300 may also have a coating 30 on the abrasive layer 11. Figure 3 An example of an abrasive pad 300 with a coating 30 is shown. In this case, the coating 30 becomes the abrasive surface 111. By giving the abrasive pad 300 a coating 30, there is a trend to further increase the design freedom, such as the wettability, surface roughness, and hardness of the abrasive pad being within a more suitable range. The coating 30 may also have multiple layers.

[0058] The materials constituting the coating 30 are not particularly limited. Examples include resins, and more specifically, thermoplastic resins such as polyethylene, polypropylene, polyvinyl chloride, polystyrene, ABS resin, acrylic resin, polycarbonate, polyamide, and polyester resin; thermosetting resins such as phenolic resin, epoxy resin, acrylic resin, urethane resin, and formaldehyde resin; photocurable resins such as isocyanurate resins, acrylic (methacrylic) ester resins and their urethane-modified resins, and Thiokol resins; and fluoropolymers such as polytetrafluoroethylene and polyvinylidene fluoride. One type of resin constituting the coating 30 may be used alone, or two or more types may be used in combination.

[0059] Relative to the total amount of coating 30, the resin content in coating 30 can be 50% by mass or more, 75% by mass or more, 90% by mass or more, 95% by mass or more, 98% by mass or more, or 100% by mass, meaning that coating 30 is formed solely of resin. Furthermore, the upper limit of the resin content in coating 30 can be 100% by mass, 98% by mass, 95% by mass, or 90% by mass.

[0060] The coating 30 may also contain metal oxides. By including metal oxides, the surface roughness and wettability can be kept within a more suitable range, and the tendency for adhering substances and grinding debris from the slurry to adhere can be further suppressed. Examples of metal atoms constituting the metal oxides include copper (Cu), zinc (Zn), titanium (Ti), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), thorium (Th), vanadium (V), molybdenum (Mo), tungsten (W), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), gallium (Ga), germanium (Ge), tin (Sn), and lead (Pb). The metal oxide constituting the coating 30 can be used alone or in combination of two or more.

[0061] Relative to the total amount of coating 30, the content of metal oxides in coating 30 can be 0.1% by mass or more, 1% by mass or more, 3% by mass or more, 5% by mass or more, 7% by mass or more, or 10% by mass or more. Furthermore, the upper limit of the content of metal oxides in coating 30 can be 30% by mass, 20% by mass, 15% by mass, or 12% by mass.

[0062] 1.4. Manufacturing method of grinding pad Figure 4 The flowchart illustrates an example of a method for manufacturing an abrasive pad according to this embodiment. The manufacturing method in this embodiment is a method for manufacturing an abrasive pad having an abrasive layer, which may include: a step S1 of forming a protrusion on one side of a film and forming a recess on a side opposite to the protrusion to obtain an abrasive layer; a step S2 of filling the recess with a material comprising a curable resin (hereinafter also referred to as a "resin composition"); and a step S3 of curing the curable resin to form a filler.

[0063] 1.4.1. Process S1 First, such as Figure 5 As shown, a membrane 40 is prepared. The membrane 40 is not particularly limited as long as it is a sheet-like component and the protrusions 113 can be formed by processing. Examples of materials constituting the membrane 40 include those used to form the abrasive layer 11. Preferably, the protrusions 113 can be formed by sheet molding. Examples of such materials include thermoplastic resins such as polyethylene, polypropylene, polyvinyl chloride, polystyrene, ABS resin, acrylic resin, polycarbonate, polyamide, and polyester resin. Furthermore, to improve adhesion with the filler 12, cover 20, and coating 30 described later, the abrasive surface side and / or back side of the membrane 40 may be roughened or coated with resin for anchoring treatment.

[0064] The thickness of the film 40 is not particularly limited, but is preferably 0.001 mm to 50 mm, more preferably 0.05 mm to 10 mm, and even more preferably 0.1 mm to 1.0 mm. By keeping the thickness of the film 40 within the above range, it tends to be easier to perform sheet molding.

[0065] Next, as Figure 6As shown, a protrusion 113 is formed on the film 40 prepared in step S1 to obtain a polishing layer 11. A recess 114 can also be formed simultaneously on the back side when forming the protrusion 113. The method for forming the protrusion 113 is not particularly limited; for example, methods such as sheet molding (vacuum forming, compressed air forming, and hot pressing) can be used to form the protrusion 113. In this embodiment, by using sheet molding, films containing resins that are difficult to solidify after filling a mold such as a gravure plate to form a raised or recessed pattern can also be used as polishing layers. The sheet molding method is not particularly limited, and conventionally known methods can be used. Alternatively, by injection molding or similar methods, heated and molten resin can be injected into a mold, thereby obtaining the polishing layer 11 without preparing a film 40.

[0066] 1.4.2. Process S2 Next, in process S2, as Figure 7 As shown, resin composition 50 is filled into recess 114. Resin composition 30 comprises a curable resin. As a curable resin, there is no particular limitation as long as it is a resin that can be cured; for example, resins exemplified as thermosetting resins and photocurable resins in the description of fillers for abrasive pads can be cited.

[0067] There are no particular limitations on the method of filling the recess 114 with the resin composition 50. For example, methods such as applying and filling by means of a scraper or the like, and injecting into the recess 113 by means of a syringe or the like, can be used.

[0068] The resin composition 50 can be filled into the recess 114 without gaps, or it can be filled into the recess 114 in a way that creates voids. By filling in a way that creates voids, voids are created in the recess 114 when the polishing pad is made. These voids can provide cushioning, thus further improving the followability of the polishing pad 10 to the workpiece and tending to improve the surface roughness of the workpiece after polishing. In addition, such a polishing pad with voids in the recess 114 is not easy to manufacture in conventional manufacturing methods, such as using a gravure to cure the resin in the shape of the gravure, but it can be easily manufactured in the manufacturing method of this embodiment, thus providing a high degree of freedom in the design of the polishing pad. As a method for creating voids, examples include: filling the recess 114 with the resin composition 50 in such a way that the volume of the filler is smaller than the volume of the recess 114; and generating air bubbles in the resin composition 50 by bubbling or the like after filling the recess 114 with the resin composition 50.

[0069] 1.4.3. Process S3 Furthermore, in process S3, such as Figure 8 As shown, the resin composition 50 that has been filled in the recess 114 is cured to form the filler 12. Figure 8As an example, this illustrates a method of curing the resin composition 50 by irradiating it with ultraviolet light L from a light source 60. This yields an abrasive pad.

[0070] Figure 8 In this method, ultraviolet light is used to cure the resin composition 50, but there is no particular limitation as long as the method is suitable for the material of the resin composition 50 used. Other methods for curing the resin composition 50 include heat curing methods (including methods of leaving at room temperature) and methods of mixing and leaving, such as in a two-component mixture.

[0071] 1.4.4. Other processes The method for manufacturing the abrasive pad in this embodiment may also include other steps (not shown). For example, it may include a step of attaching the cover portion 20 to the back surface 112 of the abrasive layer 11 in such a way that it at least covers the recess 114. If the cover portion 20 is a layered component formed from multiple sheet-like components, the pre-stacked layered cover portion 20 may be attached to the film 40, or some of the sheet-like components constituting the cover portion 20 may be sequentially attached to the film 40.

[0072] The method for manufacturing the abrasive pad in this embodiment may also include a step of bonding the coating 30 to the film 40. The bonding step of the coating 30 may occur before step S1, before step S2, before step S3, or after step S3. If the coating 30 is a layered component formed from multiple sheet-like components, the pre-layered layered coating 30 may be bonded to the film 40, or some of the sheet-like components constituting the coating 30 may be sequentially bonded to the film 40. Alternatively, the coating 30 may be bonded by applying the components forming the coating 30 to the film 40.

[0073] When a thermoplastic resin is used as the resin composition 50, the method for manufacturing the abrasive pad in this embodiment may also include a step of solidifying the resin composition 50 instead of the curing step in step S3. The solidification of the resin composition 50 may be carried out at room temperature or at a temperature cooled to below room temperature.

[0074] In another embodiment, the manufacturing method described herein is a method for manufacturing an abrasive pad having an abrasive layer. This method includes forming a protrusion on one side of the film and forming a recess on the opposite side of the film at a portion corresponding to the protrusion to obtain the abrasive layer. The method may also exclude the step of filling the recess with a material containing a curable resin, or the step of curing the curable resin to form a filler. In this case, gaps can be provided within the recess, and the size of the gaps can be adjusted, thus enabling a manufacturing method with a high degree of design freedom.

[0075] Example The present invention will be described in more detail below using examples. The present invention is not limited to the following examples.

[0076] (Making of a grinding pad) [Example 1] A 0.18 mm thick polycarbonate resin sheet is vacuum-formed with a flat portion having a roughly truncated pyramidal shape with a height of 0.35 mm and a square width of 3 mm, and a spacing of 1 mm between the protrusions. Acrylic resin is then filled into the recesses of the resin sheet to create voids on the back side of the recesses. The resin is then cured by irradiation with ultraviolet light. Next, double-sided adhesive tape is applied to the back side of the abrasive layer. A polytetrafluoroethylene sheet containing titanium dioxide is then applied to the abrasive surface side of the abrasive layer to obtain an abrasive pad.

[0077] [Example 2] A 0.18 mm thick polycarbonate resin sheet is vacuum-formed with a flat portion having approximately truncated pyramidal protrusions 0.35 mm high and 3 mm square, and a spacing of 1 mm between the protrusions. The recesses of the resin sheet are filled with acrylic resin, creating voids on the back side of the recesses. The resin is then cured by irradiation with ultraviolet light. Next, double-sided adhesive tape is adhered to the back side of the abrasive layer to obtain an abrasive pad.

[0078] [Example 3] A 0.18 mm thick polycarbonate resin sheet is vacuum-formed with a flat portion having approximately truncated pyramidal protrusions of 0.35 mm height and 3 mm square width, and a spacing of 1 mm between the protrusions. Next, double-sided adhesive tape is applied to the back side of the abrasive layer. A polytetrafluoroethylene sheet containing titanium oxide is then applied to the abrasive surface side of this abrasive layer to obtain an abrasive pad.

[0079] [Example 4] A polycarbonate resin sheet with a thickness of 0.18 mm is vacuum-formed with a flat portion having a roughly truncated pyramidal shape with a height of 0.35 mm and a square width of 3 mm, and a spacing of 1 mm between the protrusions. Next, double-sided adhesive tape is attached to the back side of the abrasive layer to obtain an abrasive pad.

[0080] [Grinding test] For the grinding pads of Examples 1 to 4, grinding tests were conducted under the following test conditions to evaluate the grinding speed and surface roughness.

[0081] (Grinding conditions) Testing machine: Small single-sided grinding machine (platform size 380mm) Slurry: Diol-based (containing 0.7% by mass of polycrystalline diamond with an average particle size of 22 μm) Slurry supply rate: 5 mL / min Load: 165g / cm 2 Speed: 100 rpm Time: 30 minutes / batch × 3 batches Workpiece to be ground: 2-inch diameter ceramic substrate (Grinding speed) The grinding speed is calculated by dividing the difference in thickness of the workpiece before and after grinding by the time. The results for the first batch are shown in Table 1.

[0082] (Surface roughness of the material being ground) The surface roughness Sa of the ground material was measured at 10x magnification using a Zygo NewView 5010 optical interferometer (product name, manufactured by Canon). The results for batch 3 are shown in Table 1.

[0083] (Pad wear) The amount of pad wear is calculated as the difference in thickness of the grinding pad before and after grinding.

[0084] [Table 1] Conventional products (having an abrasive layer obtained by curing thermosetting resin in a mold) have a grinding speed of approximately 0.10 μm / min, and the surface roughness of the workpiece after grinding is 100 nm or more. In contrast, the grinding speed of any of the abrasive pads in Examples 1 to 4 is 1.00 μm / min or more, and the surface roughness of the workpiece after grinding is 15.0 nm or less, which is excellent. Furthermore, the abrasive pad of Example 1 was subjected to a grinding test (4 batches) using a 6B double-sided polishing machine. The results showed that the wear of the pad after grinding was less than 10 μm, and the lifespan of the abrasive pad was also good.

[0085] In addition to using polycrystalline diamond with an average particle size of 18 μm, the GaN (gallium nitride) substrate was polished under the same test conditions. The results showed that the polishing speed of the conventional product was 1.10 μm / min and the surface roughness of the polished object was 180 nm. In contrast, the polishing pad of Example 1 had a polishing speed of 1.00 μm / min and a surface roughness of 100 nm. The two products achieved the same polishing speed and produced a good polished object.

[0086] Industrial availability The polishing pad of the present invention is industrially applicable as a polishing pad suitable for surface processing of optical materials such as lenses, parallel planar plates and mirrors, semiconductor wafers, semiconductor devices, hard disk substrates, metals and ceramics (especially ceramic materials).

Claims

1. Abrasive pad, which is an abrasive pad with an abrasive layer. The polishing layer has a polishing surface and a back surface opposite to the polishing surface. A protrusion is located on the polishing surface side, and a recess corresponding to the protrusion is located on the back surface side. The abrasive pad has a filler that fills the recesses of the abrasive layer. The filler contains resin.

2. The polishing pad of claim 1, wherein, On the back side within the recess, there exists a gap where the filling material is absent.

3. The polishing pad of claim 1, wherein, There is a covering portion on the back side that at least covers the recess.

4. The polishing pad of claims 1-3, wherein, The abrasive layer comprises a coating having the abrasive surface.

5. A method for manufacturing an abrasive pad, wherein the abrasive pad has an abrasive layer, the manufacturing method comprising: The process of forming a protrusion on one side of the film and forming a concave portion on the opposite side of the film corresponding to the protrusion to obtain the polishing layer; The process of filling the recess with a material comprising a curable resin; and The process of curing the curable resin to form a filler.

6. The method for manufacturing the abrasive pad as described in claim 5, wherein, After the process of forming the filler, there are gaps in the recess where the filler is not present.

7. The method of manufacturing an abrasive pad as described in claim 5 or 6, further comprising the step of laminating a coating layer on the surface of the abrasive layer having the protrusion.

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