JP6605761B1 - Abrasive - Google Patents

Abstract

An object of this invention is to provide the abrasive which can thicken a grinding | polishing part, suppressing the fall of a polishing rate. The abrasive of the present invention is an abrasive comprising a substrate and a polishing layer laminated on the surface side of the substrate and containing abrasive grains and a binder, and the polishing layer has a plurality of columnar polishing parts. The plurality of polishing parts are arranged in a staggered manner, the average thickness of the polishing part is 300 μm or more, the area of the top surface of the polishing part is 6 mm 2 or more, and the average thickness of the base material is 300 μm or more and 3000 μm. It is as follows.

Description

  The present invention relates to an abrasive.

  For example, fixed abrasive abrasives are generally used for processing glass substrates used in electronic devices such as hard disks. As such an abrasive, an abrasive constituted by laminating a polishing layer containing abrasive grains and a binder on the surface of a base material is known (see, for example, Japanese Patent No. 6091704). In the above-mentioned conventional abrasive, the polishing layer is composed of a plurality of regions (polishing portions) whose surface is divided by grooves, and the maximum peak height of the polishing portion surface is controlled, so that the processing efficiency and the finished flatness are high. Both levels are compatible.

  The above-mentioned conventional abrasive is a fixed abrasive grain system, and the polishing layer is gradually worn by polishing, and the life is reached by the abrasion of the polishing layer. Therefore, in order to extend the life of the conventional abrasive, it is necessary to increase the thickness of the polishing layer, that is, the height of each polishing portion.

  However, if the height of the polishing part is increased as it is, the aspect ratio of the polishing part becomes large, and the polishing part tends to collapse during grinding. For this reason, the abrasive tends to have a lifetime due to the falling of the polishing portion. When the aspect ratio of the polishing part is lowered in order to make the polishing part difficult to fall down, the area of each polishing part increases. When the area of each polishing part is large, the substrate is likely to warp as the polishing layer is cured and contracted when the polishing layer is produced by printing or the like. For this reason, it may be difficult to perform uniform polishing due to warpage of the substrate. By increasing the average thickness of the base material, the warpage of the base material is alleviated, but there is a limit to the relaxation. Moreover, when a base material becomes thick, the flexibility and ductility of a base material will fall, and it will become difficult for an abrasive | polishing material to track the surface shape of a to-be-cut body. For this reason, there is a possibility that a polishing rate may fall.

Japanese Patent No. 6091704

  The present invention has been made in view of such inconveniences, and an object of the present invention is to provide an abrasive capable of thickening the polishing portion while suppressing a decrease in the polishing rate.

  As a result of earnestly examining the abrasive that prevents the substrate from warping even if the polishing portion is thickened while suppressing the decrease in the polishing rate, in addition to adjusting the thickness of the substrate, the present inventors It was found that the warpage of the substrate was dramatically improved by arranging the portions in a staggered manner, and the present invention was completed. The reason why the warpage of the base material is dramatically improved by arranging the polishing portions in a staggered manner is not certain, but the warpage generated in staggered polishing portions by arranging the polishing portions in a staggered manner is not certain. It is presumed that this is because it becomes easier to cancel each other.

That is, the invention made to solve the above problems is an abrasive comprising a base material and a polishing layer laminated on the surface side of the base material and containing abrasive grains and a binder. The plurality of polishing portions are staggered, the average thickness of the polishing portions is 300 μm or more, the area of the top surface of the polishing portions is 6 mm ² or more, and the base material The average thickness of is not less than 300 μm and not more than 3000 μm.

  Since the abrasive has an area of the top surface of the polishing portion that is equal to or greater than the lower limit, even if the average thickness of the polishing portion is equal to or greater than the lower limit, the polishing portion is unlikely to fall during grinding. Further, since the abrasive has an average thickness of the base material equal to or higher than the above lower limit and a plurality of polishing portions are arranged in a staggered manner, even if the average thickness of the polishing portion is equal to or higher than the lower limit, the abrasive warps. Is unlikely to occur. Furthermore, since the said abrasive makes the average thickness of a base material below the said upper limit, it is easy to follow the surface shape of a to-be-cut body, and a polishing rate can be raised. Therefore, the abrasive can thicken the polishing portion while suppressing a decrease in the polishing rate.

  As ratio of the average thickness of the said grinding | polishing part with respect to the average thickness of the said base material, 0.7-4 is preferable. By setting the ratio of the average thickness of the polishing portion to the average thickness of the base material to be equal to or higher than the lower limit, the polishing portion can be made thick while suppressing a decrease in the polishing rate. Moreover, generation | occurrence | production of the curvature of a base material can be suppressed by making ratio of the average thickness of the said grinding | polishing part with respect to the average thickness of the said base material below an upper limit.

The value of the area of the top surface was divided by the average thickness of the abrasive portion, 0.015 mm ² / [mu] m or more 0.04 mm ² / [mu] m or less. By setting the value obtained by dividing the area of the top surface of the polishing portion by the average thickness within the above range, the polishing portion can be made thick while suppressing the occurrence of warping of the substrate.

The area of the top surface of the polishing part is preferably 100 mm ² or less, and the average thickness of the polishing part is preferably 5000 μm or less. Generation | occurrence | production of the curvature of a base material can be suppressed by making the area of the top surface of the said grinding | polishing part below into the said upper limit. Moreover, the polishing part can be made difficult to fall by setting the average thickness of the polishing part to the upper limit or less.

  The binder is preferably composed mainly of a thermosetting resin. By using a thermosetting resin as the main component of the binder, for example, it is possible to prevent the occurrence of glass cracking during polishing of the glass material.

  “The plurality of polishing portions are staggered” means that the polishing portions are arranged at equal intervals in a plurality of parallel rows, pass through the center of the polishing portions included in one row, and with respect to this one row. This is an arrangement in which the centers of the polishing portions of the one row and the adjacent row are not positioned in the orthogonal direction. The “main component” means a component having the highest content, preferably a component having a content of 50% by mass or more, more preferably 90% by mass or more.

  As described above, the abrasive of the present invention can thicken the polishing portion while suppressing a decrease in the polishing rate. Therefore, the abrasive of the present invention has a long life.

It is a typical fragmentary top view which shows the abrasives which concern on one Embodiment of this invention. It is a typical fragmentary sectional view in the AA line of FIG. It is a typical fragmentary sectional view which shows the abrasive | polishing material which concerns on embodiment different from FIG.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings as appropriate.

  The abrasive 1 shown in FIGS. 1 and 2 includes a base material 10, a polishing layer 20 laminated on the front surface side of the base material 10, and an adhesive layer 30 laminated on the back surface side of the base material 10. Further, the polishing layer 20 includes a plurality of polishing portions 20a and grooves 20b disposed between the polishing portions 20a.

  The abrasive 1 is suitably used as a fixed abrasive for polishing a surface of a glass material, particularly for polishing a surface of an aluminosilicate glass substrate used for a cover glass, a hard disk or the like.

<Base material>
The substrate 10 is a plate-like or sheet-like member for supporting the polishing layer 20.

  Although it does not specifically limit as a main component of the base material 10, Polyethylene terephthalate (PET), polycarbonate (PC), polypropylene (PP), polyethylene (PE), polyimide (PI), polyethylene naphthalate (PEN), aramid, aluminum , Copper and the like. Among these, PET, PC, and aluminum that have good adhesion to the polishing layer 20 are preferable. Moreover, the process which improves adhesiveness, such as a chemical process, a corona process, and a primer process, may be performed on the surface of the base material 10.

  Moreover, the base material 10 is good to have flexibility or ductility. Thus, since the base material 10 has flexibility or ductility, the abrasive 1 follows the surface shape of the workpiece, and the contact area between the polishing surface and the workpiece is increased. Further increase. Examples of the material of the flexible base material 10 include PET and PC. Moreover, aluminum, copper, etc. can be mentioned as a material of the base material 10 which has ductility.

  The shape and size of the base material 10 are not particularly limited. For example, a square shape having a side of 140 mm or more and 160 mm or less, a disk shape having a diameter of 200 mm or more and 2022 mm or less, a circle having an outer diameter of 200 mm or more and 2022 mm or less, and a circle having an inner diameter of 100 mm or more and 658 mm or less. It can be a ring or the like. Moreover, the structure by which the several base material 10 juxtaposed on the plane is supported by a single support body may be sufficient.

  The lower limit of the average thickness of the substrate 10 is 300 μm, and more preferably 500 μm. On the other hand, the upper limit of the average thickness of the substrate 10 is 3000 μm, and more preferably 1000 μm. If the average thickness of the substrate 10 is less than the above lower limit, the substrate 10 may be easily warped. Conversely, if the average thickness of the base material 10 exceeds the above upper limit, the flexibility of the base material 10 becomes insufficient, and the effect of improving the polishing rate may be insufficient.

<Polishing layer>
The polishing layer 20 includes a plurality of abrasive grains 21 and a binder 22 in the polishing portion 20a.

(Abrasive grains)
Examples of the abrasive grains 21 include diamond abrasive grains, alumina abrasive grains, silica abrasive grains, ceria abrasive grains, and silicon carbide abrasive grains. Among them, diamond abrasive grains that are harder than other abrasive grains are preferable. By using the abrasive grains 21 as diamond abrasive grains, the polishing power can be improved and the polishing rate can be further improved.

  Note that the diamond of the diamond abrasive grains may be single crystal or polycrystalline, or may be diamond that has been subjected to treatment such as Ni coating. Of these, single crystal diamond and polycrystalline diamond are preferable. Single crystal diamond is harder than other diamonds and has higher grinding power. In addition, since polycrystalline diamond is easy to cleave in a microcrystalline unit constituting the polycrystal and hardly crushes, the decrease in the polishing rate is small even if polishing is performed for a long time.

  The average particle diameter of the abrasive grains 21 is appropriately selected from the viewpoint of the polishing rate and the surface roughness of the workpiece after polishing. As a minimum of the average particle diameter of abrasive grain 21, 2 micrometers is preferred, 10 micrometers is more preferred, and 15 micrometers is still more preferred. On the other hand, the upper limit of the average particle diameter of the abrasive grains 21 is preferably 150 μm, more preferably 125 μm, and even more preferably 100 μm. When the average particle diameter of the abrasive grains 21 is less than the above lower limit, the polishing power of the abrasive 1 is insufficient, and the polishing rate may be reduced. Conversely, when the average particle diameter of the abrasive grains 21 exceeds the above upper limit, the polishing accuracy may be reduced. Here, the “average particle size” refers to a 50% value (50% particle size, D50) of a volume-based cumulative particle size distribution curve measured by a laser diffraction method or the like.

  As a minimum of content of abrasive grain 21 in polish part 20a, 0.5 volume% is preferred, 2 volume% is more preferred, and 4 volume% is still more preferred. On the other hand, as an upper limit of content of the said abrasive grain 21, 55 volume% is preferable, 45 volume% is more preferable, and 35 volume% is further more preferable. If the content of the abrasive grains 21 is less than the lower limit, the polishing power of the polishing layer 20 may be insufficient. Conversely, if the content of the abrasive grains 21 exceeds the upper limit, the polishing layer 20 may not be able to hold the abrasive grains 21.

(binder)
Although it does not specifically limit as a main component of the binder 22, Resin or an inorganic substance is mentioned. Among them, a resin, particularly a thermosetting resin, is preferable because it is less likely to cause glass breakage when polishing a glass material and is suitable for glass polishing.

  Examples of the resin include polyurethane, phenol resin, epoxy, polyester, cellulose, ethylene copolymer, polyvinyl acetal, polyacrylic acid and salts thereof, polyacrylate ester, polyvinyl alcohol, polyvinyl chloride, polyvinyl acetate, polyamide, and the like. Resins can be mentioned. Of these, polyacrylates, epoxies, polyesters, and polyurethanes that are easy to ensure good adhesion to the substrate 10 are preferable, and epoxy having thermosetting properties is more preferable. The resin may be at least partially crosslinked.

  Examples of the inorganic substance include silicate, phosphate, and polyvalent metal alkoxide. Among them, a silicate having a high abrasive grain holding power is preferable. Examples of such silicates include sodium silicate and potassium silicate.

  The binder 22 may appropriately contain various auxiliary agents and additives such as a dispersant, a coupling agent, a surfactant, a lubricant, an antifoaming agent, and a colorant depending on the purpose.

(Other)
In addition, the polishing layer 20 may include a filler in the polishing portion 20a. Examples of such a filler include oxides such as alumina, silica, cerium oxide, magnesium oxide, zirconia, and titanium oxide, and composite oxides such as silica-alumina, silica-zirconia, and silica-magnesia. You may use these individually or in combination of 2 or more types as needed. Among these, alumina that can provide high polishing power is preferable.

  The average particle diameter of the filler also depends on the average particle diameter of the abrasive grains 21, but the lower limit of the average particle diameter of the filler is preferably 0.01 μm and more preferably 2 μm. On the other hand, the upper limit of the average particle diameter of the filler is preferably 40 μm, more preferably 20 μm, and even more preferably 15 μm. If the average particle size of the filler is less than the lower limit, the polishing rate may be lowered due to insufficient effect of improving the elastic modulus of the binder 22 by the filler. On the other hand, when the average particle diameter of the filler exceeds the upper limit, the filler may hinder the polishing power of the abrasive grains 21.

  The average particle diameter of the filler is preferably smaller than the average particle diameter of the abrasive grains 21. As a minimum of a ratio of an average particle diameter of the above-mentioned filler to an average particle diameter of abrasive grain 21, 0.01 is preferred, 0.05 is more preferred, and 0.1 is still more preferred. On the other hand, the upper limit of the ratio of the average particle diameter of the filler to the average particle diameter of the abrasive grains 21 is preferably 0.8, and more preferably 0.6. If the ratio of the average particle diameter of the filler to the average particle diameter of the abrasive grains 21 is less than the lower limit, the polishing rate may be reduced due to insufficient effect of improving the elastic modulus of the binder 22 by the filler. Conversely, if the ratio of the average particle diameter of the filler to the average particle diameter of the abrasive grains 21 exceeds the upper limit, the filler may impair the polishing power of the abrasive grains 21.

  The content of the filler with respect to the polishing part 20a depends on the content of the abrasive grains 21, but the lower limit of the content of the filler with respect to the polishing part 20a is preferably 15% by volume, more preferably 30% by volume. preferable. On the other hand, the upper limit of the content of the filler is preferably 75% by volume, more preferably 72% by volume. If the content of the filler is less than the lower limit, the polishing rate may be lowered due to insufficient effect of improving the elastic modulus of the binder 22 by the filler. Conversely, if the content of the filler exceeds the upper limit, the filler may hinder the polishing power of the abrasive grains 21.

(Polishing part)
The polishing part 20a is columnar. That is, the area of the bottom surface of the polishing portion 20a is 0.9 to 1.5 times, preferably 0.93 to 1.2 times, more preferably 0.95, the area of the top surface of the polishing portion 20a. It is not less than twice and not more than 1.05 times.

  The plurality of polishing portions 20a are staggered in the same shape. The shape of the top surface of the polishing portion 20a can be a circular shape as shown in FIG. 1, a square shape, a polygonal shape, or the like. From the viewpoint of the effect of reducing the warpage of the substrate 10, a circular shape or a square shape with relatively low anisotropy is preferable, and a circular shape is particularly preferable.

  The plurality of polishing units 20a are arranged in a plurality of parallel rows. The intervals (distance between centers, pitch) of the polishing portions 20a arranged in one row are equal. The interval between the polishing portions 20a is the same between a plurality of rows. Further, an interval between a plurality of rows (a distance between straight lines connecting the centers of the polishing portions 20a in each row) is equal to the interval between the polishing portions 20a. Further, the centers of the polishing portions 20a in the row adjacent to the one row are located in a direction orthogonal to the one row from the midpoint of a straight line connecting the centers of the polishing portions 20a adjacent in the one row. That is, the position of the polishing unit 20a in the adjacent row is shifted by a half pitch from the position of the polishing unit 20a in one row. Therefore, as for the arrangement of the plurality of polishing portions 20a, the same pattern is repeated every two rows in the plurality of rows. Thus, by arrange | positioning the some grinding | polishing part 20a, the curvature of the base material 10 can be reduced effectively.

  The lower limit of the average pitch of the polishing portions 20a arranged in one row is preferably 3 mm, and more preferably 5 mm. On the other hand, the upper limit of the average pitch is preferably 15 mm, and more preferably 10 mm. If the average pitch is less than the lower limit, the average area of the top surface of the polishing portion 20a cannot be increased, and the polishing portion 20a may easily fall during polishing. On the contrary, when the average pitch exceeds the upper limit, the width of the groove 20b between the adjacent polishing portions 20a is increased, and the base material 10 is likely to be warped.

The lower limit of the average area of the top surface of the polishing unit 20a is 6 mm ² and more preferably 15 mm ² . On the other hand, as an upper limit of the average area of the top surface of the polishing part 20a, 100 mm ² is preferable, and 30 mm ² is more preferable. If the average area of the top surface of the polishing portion 20a is less than the above lower limit, the polishing portion 20a may easily fall down during polishing. Conversely, if the average area of the top surface of the polishing part 20a exceeds the above upper limit, the substrate 10 may be easily warped.

  The lower limit of the area occupation ratio of the plurality of polishing portions 20a with respect to the entire polishing layer 20 is preferably 5%, more preferably 20%, and even more preferably 30%. On the other hand, the upper limit of the area occupation ratio of the polishing portion 20a is preferably 60% and more preferably 55%. If the area occupancy of the polishing portion 20a is less than the lower limit, the pressure applied during polishing is excessively concentrated on the polishing portion 20a, which may cause the polishing portion 20a to peel from the substrate 10. Conversely, if the area occupancy ratio of the polishing portion 20a exceeds the upper limit, the contact area of the polishing layer 20 with the workpiece during polishing increases, and the polishing rate may decrease due to frictional resistance. The “area of the entire polishing layer” is a concept including the area of the groove of the polishing layer.

  As a minimum of average thickness of polish part 20a, it is 300 micrometers and 1000 micrometers is more preferred. On the other hand, the upper limit of the average thickness of the polishing portion 20a is preferably 5000 μm and more preferably 3000 μm. If the average thickness of the polishing portion 20a is less than the above lower limit, the life may be insufficient. On the contrary, if the average thickness of the polishing part 20a exceeds the upper limit, the polishing part 20a may be easily collapsed during polishing.

  As a minimum of ratio of average thickness of polish part 20a to average thickness of substrate 10, 0.7 is preferred and 1 is more preferred. On the other hand, the upper limit of the ratio of the average thickness of the polishing portion 20a is preferably 4, and more preferably 2.5. When the ratio of the average thickness of the polishing portion 20a is less than the lower limit, a warp reduction effect due to the thickness of the base material 10 cannot be sufficiently obtained with respect to a decrease in the polishing rate due to the base material 10 becoming thick. There is a fear. Conversely, if the ratio of the average thickness of the polishing portion 20a exceeds the upper limit, the substrate 10 may be easily warped.

The lower limit of the value of the area of the top surface is divided by the average thickness of the polishing portion 20a (the area / thickness ratio) is preferably from ^{0.015mm 2 / μm, 0.02mm 2 /} μm is more preferable. On the other hand, the upper limit of the area / thickness ratio is preferably ^{0.04mm 2 / μm, 0.03mm 2 /} μm is more preferable. If the area / thickness ratio is less than the lower limit, the polishing portion 20a may easily fall during polishing. On the contrary, when the area / thickness ratio exceeds the upper limit, the substrate 10 may be easily warped.

(groove)
The bottom surface of the groove 20 b is configured by the surface of the base material 10.

  The average width of the groove 20b is determined by the area of the top surface of the polishing portion 20a and the area occupancy. The lower limit of the average width of the groove 20b is preferably 0.3 mm, and more preferably 0.5 mm. On the other hand, the upper limit of the average width of the grooves 20b is preferably 10 mm, and more preferably 8 mm. If the average width of the grooves 20b is less than the above lower limit, the polishing powder generated by polishing may be clogged in the grooves 20b. On the contrary, if the average width of the groove 20b exceeds the upper limit, the work body is likely to fall into the groove 20b during polishing, which may cause damage to the work body. The “average width of the groove” means the length (D in FIG. 1) of the portion where the straight line L connecting the centers M of the adjacent polishing portions 20a in one row passes through the groove 20b as shown in FIG. Point to.

<Adhesive layer>
The adhesive layer 30 is a layer that supports the abrasive 1 and fixes the abrasive 1 to a support for mounting on the polishing apparatus.

  Although it does not specifically limit as an adhesive agent used for this contact bonding layer 30, For example, the reactive adhesive, an instant adhesive agent, a hot-melt adhesive agent, the adhesive agent which can be replaced, etc. can be mentioned.

  As the adhesive used for the adhesive layer 30, a pressure-sensitive adhesive is preferable. By using a pressure-sensitive adhesive as the adhesive used for the adhesive layer 30, the abrasive 1 can be peeled off from the support and can be replaced, so that the abrasive 1 and the support can be easily reused. Such an adhesive is not particularly limited. For example, an acrylic adhesive, an acrylic-rubber adhesive, a natural rubber adhesive, a synthetic rubber adhesive such as butyl rubber, a silicone adhesive, and a polyurethane adhesive. Agents and the like.

  The lower limit of the average thickness of the adhesive layer 30 is preferably 0.05 mm, and more preferably 0.1 mm. On the other hand, the upper limit of the average thickness of the adhesive layer 30 is preferably 0.3 mm, and more preferably 0.2 mm. When the average thickness of the adhesive layer 30 is less than the above lower limit, the adhesive force is insufficient, and the abrasive 1 may be peeled off from the support. On the contrary, when the average thickness of the adhesive layer 30 exceeds the above upper limit, for example, due to the thickness of the adhesive layer 30, there is a possibility that the workability may be lowered, such as causing trouble when the abrasive 1 is cut into a desired shape. .

<Abrasive manufacturing method>
The abrasive 1 can be manufactured, for example, by a manufacturing method mainly including a preparation step, a polishing layer forming step, and an adhesive layer sticking step.

(Preparation process)
In the preparation step, a polishing layer composition containing the abrasive grains 21 and the binder 22 is prepared.

  Specifically, a polishing layer composition containing a material for forming the abrasive grains 21 and the binder 22 is prepared as a coating liquid. In addition, since content of the abrasive grain 21 in solid content turns into content of the abrasive grain 21 of the grinding | polishing part 20a after manufacture, the quantity of solid content is adjusted so that content in the grinding | polishing part 20a may become a desired value. Determine as appropriate.

  Also, a diluent such as water or alcohol is added to control the viscosity and fluidity of the coating solution. By this dilution, a part of the abrasive grains 21 included in the polishing part 20 a can be protruded from the surface of the binder 22. That is, by adding a diluent, the thickness of the binder 22 is reduced when the polishing layer composition is dried in the polishing layer forming step, and the protruding amount of the abrasive grains 21 can be increased. Therefore, a high polishing rate can be expressed from the initial stage of polishing by this dilution.

(Polishing layer forming process)
In the polishing layer formation step, the polishing layer 20 is formed by printing the polishing layer composition prepared in the preparation step. The polishing layer forming step includes a coating step and a drying step.

[Coating process]
In the coating step, the polishing layer composition is applied to the surface of the substrate 10.

  Specifically, using the coating liquid prepared in the preparation step, the polishing layer 20 having a plurality of polishing portions 20a and grooves 20b disposed between the polishing portions 20a is formed on the surface of the substrate 10 by a printing method. To do. In order to form the groove 20b, a mask having a shape corresponding to the shape of the groove 20b is prepared, and the coating liquid is printed through the mask. As this printing method, for example, screen printing, metal mask printing or the like can be used.

  As the mask for printing, a mask made of SUS or fluorine resin is preferable. Since the mask made of SUS or fluororesin can thicken the mask, the polishing portion 20a having a large average thickness can be easily manufactured.

  The thickness of the polishing portion 20a can be adjusted mainly by the thickness of the mask and the coating amount. Therefore, in this coating step, the coating amount of the polishing layer composition may be adjusted so that the average thickness of the polishing portion 20a is a desired value.

[Drying process]
In the drying step, the coating liquid (composition for the polishing layer) after the coating step is dried by heating. The coating liquid is cured by this heat drying, and the polishing layer 20 is formed. This drying process is performed by removing the mask.

  As a minimum of heating temperature in a drying process, 80 ° C is preferred and 100 ° C is more preferred. On the other hand, the upper limit of the heating temperature is preferably 300 ° C, more preferably 200 ° C. If the heating temperature is less than the lower limit, the composition for the polishing layer is not sufficiently cured, the amount of wear increases, and the life of the abrasive 1 may be shortened. Conversely, if the heating temperature exceeds the upper limit, the polishing part 20a may be altered by heat.

  Although the heating time in the drying step depends on the heating temperature, the lower limit of the heating time is preferably 2 hours, more preferably 2.5 hours. On the other hand, the upper limit of the heating time is preferably 40 hours, more preferably 32 hours, and even more preferably 20 hours. When the heating time is less than the lower limit, the composition for the polishing layer is not sufficiently cured, the amount of wear increases, and the life of the abrasive 1 may be shortened. Conversely, if the heating time exceeds the upper limit, the production efficiency may be reduced.

(Adhesive layer application process)
In the adhesive layer sticking step, the adhesive layer 30 is laminated on the back surface side of the substrate 10. Specifically, for example, a previously formed tape-like adhesive layer 30 is attached to the back surface of the substrate 10.

<Advantages>
Since the abrasive 1 has an area of the top surface of the polishing portion 20a of 6 mm ² or more, even if the average thickness of the polishing portion 20a is 300 μm or more, the polishing portion 20a hardly falls during grinding. Further, since the abrasive 1 has an average thickness of the substrate 10 of 300 μm or more and a plurality of polishing portions 20a are arranged in a staggered manner, even if the average thickness of the polishing portions 20a is 300 μm or more, the substrate 10 Is less likely to warp. Furthermore, since the abrasive 1 has an average thickness of the substrate 10 of 3000 μm or less, it is easy to follow the surface shape of the workpiece, and the polishing rate can be increased. Therefore, the abrasive 1 can thicken the polishing portion 20a while suppressing a decrease in the polishing rate.

[Other Embodiments]
The present invention is not limited to the above-described embodiment, and can be implemented in a mode in which various changes and improvements are made in addition to the above-described mode.

  In the above embodiment, a case has been described in which the interval between the rows of the plurality of polishing portions is made equal to the interval between the polishing portions in one row, but the interval between the rows is the interval between the polishing portions in one row. And may be different. For example, a plurality of polishing units may be arranged in one row of polishing units and in a row adjacent to the polishing unit, and two polishing units in the vicinity of the polishing unit may form an equilateral triangle. Good. In addition, when making the space | interval between rows different from the space | interval between the grinding | polishing parts in one row | line | column, it is preferable that it is 3 mm or more and 15 mm or less as a space | interval between rows. If the distance between the rows is less than the above lower limit, the average area of the top surface of the polishing part cannot be increased, and the polishing part may easily fall during polishing. On the other hand, if the distance between the rows exceeds the above upper limit, the width of the groove between the adjacent rows becomes large, and the base material may be easily warped.

  In the above embodiment, the case where the position of the polishing portion in the adjacent row is shifted by a half pitch from the position of the polishing portion in one row has been described. However, the shift in this position is not limited to a half pitch. / 3 pitch may be used. In this case, the same pattern is repeated every three rows as the arrangement of the plurality of polishing portions.

  In the above embodiment, the case where the abrasive has the adhesive layer has been described. However, the adhesive layer is not an essential constituent element and can be omitted. When the abrasive does not have an adhesive layer, the adhesive layer sticking step of the abrasive manufacturing method is omitted.

  Alternatively, as shown in FIG. 3, the abrasive 2 may include a support body 40 laminated via an adhesive layer 30 on the back surface side and a second adhesive layer 31 laminated on the back surface side of the support body 40. . When the abrasive 2 includes the support 40, the handling of the abrasive 2 is facilitated.

  Examples of the main component of the support 40 include thermoplastic resins such as polypropylene, polyethylene, polytetrafluoroethylene, and polyvinyl chloride, and engineering plastics such as polycarbonate, polyamide, and polyethylene terephthalate. By using such a material as the main component of the support body 40, the support body 40 has flexibility, the abrasive 2 follows the surface shape of the workpiece, and the polishing surface and the workpiece are in contact with each other. Therefore, the polishing rate is further improved.

  As an average thickness of the support body 40, it is 0.5 mm or more and 3 mm or less, for example. If the average thickness of the support 40 is less than the above lower limit, the strength of the abrasive 2 may be insufficient. On the other hand, if the average thickness of the support 40 exceeds the above upper limit, it may be difficult to attach the support 40 to the polishing apparatus, or the flexibility of the support 40 may be insufficient.

  The second adhesive layer 31 can use the same adhesive as the adhesive layer 30. The second adhesive layer 31 can have an average thickness similar to that of the adhesive layer 30.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated further in detail, the said invention is not limited to a following example.

[Example 1]
Diamond abrasive grains (“SCMD-C12-22” from Sino Crystal Diamond, average particle size 16 μm), alumina as filler (Al ₂ O ₃ , “LA4000” from Pacific Random Co., Ltd., average particle size 4 μm), and Mix the epoxy resin (Mitsubishi Chemical Co., Ltd. “JER828”) as a binder, adjust the content of diamond abrasive grains in the solid content to 3% by volume, and the content of filler to 75% by volume, A coating solution was obtained.

A base material (average thickness: 500 μm) mainly composed of polycarbonate, which is a thermosetting resin, was prepared as a base material, and the surface of the base material was coated by printing using the coating liquid. As a printing pattern, a metal mask having a circular opening (average area 11.95 mm ² ) having a diameter of 3.9 mm in plan view with an area occupation ratio of 9% and an average thickness of 350 μm was used. . The openings are staggered. The coating amount was adjusted so that the average thickness of the polished part was 350 μm. The coating solution was cured by drying in an oven at 120 ° C. for 16 hours. In this way, an abrasive of Example 1 was obtained.

[Example 2]
An aluminum sheet (A1050, average thickness 300 μm) was prepared as a base material, and was coated on the surface of the base material by printing using the same coating liquid as in Example 1. As a printing pattern, a metal mask having a square-shaped (average area: 6.76 mm ² ) opening having a side of 2.6 mm in plan view with an area occupation ratio of 44% and an average thickness of 350 μm is used. It was. The openings are staggered. The coating amount was adjusted so that the average thickness of the polished part was 350 μm. The coating solution was cured by drying in an oven at 120 ° C. for 16 hours. In this way, an abrasive of Example 2 was obtained.

[Example 3]
An aluminum sheet (average thickness: 300 μm) was prepared as a base material, and was coated on the surface of this base material by printing using the same coating liquid as in Example 1. As a printing pattern, a fluororesin mask having a circular opening (average area 28.27 mm ² ) having a diameter of 6 mm in plan view with an area occupation ratio of 44% and an average thickness of 1000 μm was used. The openings are staggered. Further, the coating amount was adjusted so that the average thickness of the polished part was 1000 μm. The coating solution was cured by drying in an oven at 120 ° C. for 16 hours. In this way, an abrasive of Example 3 was obtained.

[Example 4]
An abrasive of Example 4 was obtained in the same manner as Example 3 except that a base material (average thickness: 500 μm) containing polycarbonate as a main component was used as the base material.

[Example 5]
A base material (average thickness: 500 μm) containing polycarbonate as a main component was prepared as a base material, and was coated on the surface of this base material by printing using the same coating liquid as in Example 1. As a printing pattern, a fluororesin mask having a square shape (average area of 6.76 mm ² ) having a side of 2.6 mm in plan view with an area occupation ratio of 44% and an average thickness of 350 μm is used. Using. The openings are staggered. The coating amount was adjusted so that the average thickness of the polished part was 350 μm. The coating solution was cured by drying in an oven at 120 ° C. for 16 hours. In this way, an abrasive of Example 5 was obtained.

[Comparative Example 1]
A base material composed mainly of polyethylene terephthalate (“Melinex S” manufactured by Teijin DuPont Films Ltd., average thickness: 75 μm) is prepared as the base material, and this base material is coated using the same coating liquid as in Example 1. The surface was coated by printing. As a printing pattern, a metal mask having a square-shaped opening (average area 2.25 mm ² ) with an area occupancy of 36% and an average thickness of 350 μm is used. It was. In addition, the said opening part is the block pattern shape arranged regularly. The coating amount was adjusted so that the average thickness of the polished part was 350 μm. The coating solution was cured by drying in an oven at 120 ° C. for 16 hours. In this way, an abrasive of Comparative Example 1 was obtained.

[Comparative Example 2]
A polishing material of Comparative Example 2 was obtained in the same manner as Comparative Example 1 except that an aluminum sheet (average thickness of 300 μm) was used as the substrate.

[Comparative Example 3]
A base material (average thickness: 100 μm) containing polycarbonate as a main component was prepared as a base material, and the surface of the base material was coated by printing using the same coating liquid as in Example 1. As a printing pattern, a fluororesin mask having an opening of a circular shape (average area 28.27 mm ² ) having a diameter of 6 mm in plan view with an area occupation ratio of 44% and an average thickness of 1000 μm was used. The openings are staggered. Further, the coating amount was adjusted so that the average thickness of the polished part was 1000 μm. The coating solution was cured by drying in an oven at 120 ° C. for 16 hours. In this way, an abrasive of Comparative Example 3 was obtained.

[Comparative Example 4]
A base material (average thickness: 500 μm) containing polycarbonate as a main component was prepared as a base material, and was coated on the surface of this base material by printing using the same coating liquid as in Example 1. As a printing pattern, a mask made of a fluororesin having a square shape (average area: 16 mm ² ) having a side of 4 mm in plan view with an area occupation ratio of 34% and an average thickness of 350 μm was used. In addition, the said opening part is the block pattern shape arranged regularly. The coating amount was adjusted so that the average thickness of the polished part was 350 μm. The coating solution was cured by drying in an oven at 120 ° C. for 16 hours. In this way, an abrasive of Comparative Example 4 was obtained.

[Evaluation]
About the abrasive | polishing material of Examples 1-5 and Comparative Examples 1-4, the curvature of the abrasive | polishing material, the lifetime of the abrasive | polishing material, and the difficulty of falling of a grinding | polishing part were evaluated with the following judgment criteria. The results are shown in Table 1.

<War of abrasive>
The warpage of the abrasive was visually determined according to the following criteria.
A: There is no deformation on the back side (the side opposite to the surface on which the polishing layer is formed) of the base material, and no warpage is recognized.
B: Deformation is observed on the back side of the base material, but follows the flat surface when the abrasive is left on the flat surface.
C: Deformation is observed on the back side of the base material, and warping is recognized even when left on a flat surface.

<Abrasive life>
The life of the abrasive is considered to be determined by the average thickness of the polished part. Therefore, the following criteria were used.
A: The average thickness of the polished part is 1000 μm or more and has a long life.
B: The average thickness of the polished part is 300 μm or more and less than 1000 μm, and the life is slightly short.
C: The average thickness of the polished part is less than 300 μm and the life is short.

<Hardness of the grinding part to fall over>
It is considered that the difficulty of falling of the polishing portion is determined by the ratio of the height to the area of the top surface of the polishing portion. Specifically, it is considered that the larger the value (area / thickness ratio) obtained by dividing the area of the top surface of the polished portion by the average thickness, the more difficult it is to collapse. Therefore, the area / thickness ratio was calculated, and the following criterion was used based on the calculated value.
A: The area / thickness ratio is 0.02 mm ² / μm or more, and the polished part is difficult to collapse.
B: area / a thickness ratio 0.015 mm ² / [mu] m or more 0.02mm less than ² / [mu] m, the polishing unit is relatively difficult fall.
C: The area / thickness ratio is less than 0.015 mm ² / μm, and the polished part is easily collapsed.

  In Table 1, “PC” means polycarbonate, “PET” means polyethylene terephthalate, and “Al” means an aluminum sheet for the material of the substrate.

From Table 1, it can be seen that in the abrasives of Examples 1 to 5, the polishing part is difficult to collapse, and the warp of the substrate is suppressed while the polishing layer has a thick and long life. On the other hand, in the abrasives of Comparative Examples 1 and 3, since the average thickness of the base material is less than 300 μm, the base material is warped. In the polishing material of Comparative Example 2, since the area of the top surface of the polishing portion is less than 6 mm ² , the polishing portion tends to collapse. In the polishing material of Comparative Example 4, since the polishing portions are not arranged in a staggered manner, warping of the base material occurs.

From the above results, a plurality of polishing portions of the abrasive material are arranged in a staggered manner, the area of the top surface of the polishing portion is 6 mm ² or more, and the average thickness of the substrate is 300 μm or more. It can be seen that an abrasive that has a long life with an average polishing layer thickness of 300 μm or more and an excellent polishing rate can be obtained.

  The abrasive of the present invention can thicken the polishing portion while suppressing a decrease in the polishing rate. Therefore, the abrasive of the present invention has a long life.

DESCRIPTION OF SYMBOLS 1, 2 Abrasive material 10 Base material 20 Polishing layer 20a Polishing part 20b Groove 21 Abrasive grain 22 Binder 30 Adhesive layer 31 2nd adhesive layer 40 Support body

Claims (2)

A polishing material comprising a base material and a polishing layer laminated on the surface side of the base material and containing abrasive grains and a binder,
The polishing layer has a plurality of columnar polishing portions,
The plurality of polishing parts are arranged in a staggered manner,
The average thickness of the polishing part is 300 μm or more,
Area of the top surface of the abrasive part is at 15 mm ² or more 100 mm ² or less,
Ri Der average thickness of 300μm or more 3000μm or less of the substrate,
Value the area of the top surface is divided by the average thickness of the abrasive portion is at 0.015 mm ² / [mu] m or more 0.04 mm ² / [mu] m or less,
An abrasive having a ratio of an average thickness of the polishing portion to an average thickness of the substrate of 1 or more and 4 or less . The abrasive according to claim 1, wherein the binder contains a thermosetting resin as a main component.

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