WO2019123922A1

WO2019123922A1 - Polishing material and method for manufacturing polishing material

Info

Publication number: WO2019123922A1
Application number: PCT/JP2018/042368
Authority: WO
Inventors: 聡一郎中根; 友樹岩永
Original assignee: バンドー化学株式会社
Priority date: 2017-12-19
Filing date: 2018-11-15
Publication date: 2019-06-27
Also published as: JPWO2019123922A1; CN110177653A; CN110177653B

Abstract

The purpose of the present invention is to provide a polishing material whereby a polishing part can be made thicker while a reduction in polishing rate is suppressed, and a method for manufacturing a polishing material. This polishing material (1) is provided with a substrate (10) and a polishing layer (20) that includes abrasive grains (21) and a binder (22) and is layered on the surface side of the substrate (10), the polishing layer (20) having a plurality of columnar polishing parts (20a), the polishing parts (20a) including fumed silica, and the substrate (10) having a heat-resistant resin as a main component thereof.

Description

Abrasive material and method of manufacturing abrasive material

The present invention relates to an abrasive and a method of manufacturing the abrasive.

For example, in the processing of a glass substrate used in an electronic device such as a hard disk, an abrasive of fixed abrasive is generally used. As such an abrasive, an abrasive composed of an abrasive layer containing abrasive grains and a binder laminated on the surface of a substrate is known.

In the fixed abrasive, the polishing layer is composed of a plurality of polishing parts. By thus configuring the polishing layer with a plurality of polishing portions, the occupancy rate of the area in contact with the workpiece decreases, and the surface pressure at the time of polishing increases, so a high polishing rate can be expressed. In addition, since grinding dust can be removed by the grooves formed between the plurality of polishing portions, it is possible to suppress a decrease in the polishing rate due to clogging of the abrasive.

In such an abrasive, the abrasive layer is gradually worn away with the processing of the glass substrate, and therefore, in order to increase the life of the abrasive, it is required to thicken the abrasive portion. The polishing layer is generally formed using a printing method. In the case of using the printing method, if the thickness of the polishing portion is increased, the aspect ratio is increased, so that the liquid tends to drip during printing, and it becomes difficult to form each polishing portion in a columnar shape. For this reason, in the conventional thick abrasive of the polishing portion, a pyramidal polishing portion or a polishing portion having a large top surface area is used (see, for example, JP-A-2014-18893).

However, when the polishing portion is formed in a pyramidal shape, the area of the top surface of the polishing portion increases as the polishing layer wears, so the surface pressure at the time of polishing may decrease and the polishing rate may decrease. In addition, when the area of the polishing portion is increased, it is necessary to widen the width of the groove between the polishing portions in order to reduce the area occupancy rate. When the width of the groove is increased, the workpiece tends to fall into the groove, and therefore, the workpiece may be wrinkled. For this reason, when the area of the polishing portion is increased, it is difficult to reduce the area occupancy rate, so the contact pressure at the time of polishing may be decreased, and the polishing rate may be decreased.

JP, 2014-18893, A

The present invention has been made in view of such problems, and it is an object of the present invention to provide an abrasive and a method of manufacturing the abrasive, which can thicken the polishing portion while suppressing a decrease in the polishing rate.

As a result of intensive investigations by the present inventors on a method of producing an abrasive material capable of forming individual polished portions in a columnar shape even if the polished portions are thickened, the fumed silica is contained in the polished portions to print the polished layer. It paid attention to the fact that the liquid dripping at the time of formation is suppressed, and it becomes easy to form each polished part in a column. In the case where the polishing portion contains fumed silica, the adhesion between the base and the polishing portion may be lowered and it may be easily peeled off. The present inventors have found that the ease of peeling between the substrate and the polishing portion can be solved by using a substrate containing a heat resistant resin as a main component as the substrate, and completed the present invention.

That is, the invention made in order to solve the above-mentioned subject is an abrasives provided with a substrate, and an abrasive layer laminated on the surface side of this substrate and containing an abrasive grain and a binder, and the above-mentioned abrasive layer is plural. The polishing portion has fumed silica, and the base material contains a heat resistant resin as a main component.

Since the said polishing part contains fumed silica, the said polishing material can form a polishing part in columnar shape, even if it is a thick grinding | polishing part. For this reason, since it is not necessary to make the abraded part into a cone shape or to increase the area of the top surface of the abraded part, the abrading rate of the abradable material hardly decreases even if the abraded layer is worn. Moreover, since the said base material has heat resistant resin as a main component, the said abrasives can suppress the fall of the adhesiveness of the base material and grinding | polishing part by the abrasive | polishing part containing fumed silica. For this reason, the said abrasives are hard to peel off a base material and a grinding | polishing part. Therefore, the said abrasives can thicken a grinding | polishing part, suppressing the fall of a grinding | polishing rate.

As content of the said fumed silica in the said grinding | polishing part, 0.1 volume% or more and 20 volume% or less are preferable. By setting the content of the fumed silica in the polishing portion in the above range, it is possible to stably form a columnar polishing portion while suppressing the decrease in adhesion due to the fumed silica content at the time of production of the abrasive. Therefore, a more stable polishing rate can be expressed.

As average thickness of the said grinding | polishing part, 300 micrometers or more and 5000 micrometers or less are preferable. By setting the average thickness of the polishing portion in the above range, the effect of exhibiting a stable polishing rate by the inclusion of fumed silica in the polishing portion is easily exhibited.

The substrate may be polycarbonate or biaxially stretched polyethylene terephthalate. By making the said base material into a polycarbonate or a biaxially-stretched polyethylene terephthalate, the adhesiveness of a base material and a grinding | polishing part can increase, and it can further make a base | substrate and a grinding | polishing part peeling difficult.

Another invention made in order to solve the above-mentioned subject is a manufacturing method of an abrasives provided with a substrate and an abrasive layer laminated on the surface side of this substrate and containing an abrasive grain and a binder. For forming the polishing layer by printing the composition for polishing, the polishing layer has a plurality of columnar polishing portions, the composition for polishing layer contains fumed silica, and the substrate is a heat resistant resin As the main component.

In the method for producing an abrasive, since the composition for the abrasive layer contains fumed silica, when forming the abrasive layer by printing, the fumed silica gives thixotropy to the composition for the abrasive layer and suppresses dripping. it can. For this reason, even if it is a thick grinding | polishing part, a columnar grinding | polishing part can be formed by using the manufacturing method of the said abrasives. Further, in the method of manufacturing the abrasive, the base material contains the heat resistant resin as a main component, and therefore, even if the composition for the abrasive layer contains fumed silica, the base and the abrasive part are hardly peeled off. Therefore, by using the method for producing the abrasive, it is possible to produce an abrasive having a thick polishing portion while suppressing a decrease in the polishing rate.

Here, the "main component" means a component with the highest content, preferably a component with a content of 50% by mass or more, more preferably 90% by mass or more.

As described above, in the abrasive of the present invention and the abrasive produced by the method of producing an abrasive of the present invention, the thickness of the polishing portion can be increased while suppressing a decrease in the polishing rate. Therefore, the abrasives of the present invention and the abrasive produced by the method of producing an abrasive of the present invention can have a long life while exhibiting a stable polishing rate.

It is a typical fragmentary plan view showing the abrasives concerning one embodiment of the present invention. It is a typical fragmentary sectional view in the AA line of FIG. It is a flowchart which shows the manufacturing method of the abrasives which concern on one Embodiment of this invention. FIG. 3 is a schematic partial cross-sectional view showing an abrasive according to an embodiment different from FIG. 2;

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

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

The said abrasives 1 are used suitably, for example as a fixed abrasive abrasives for surface grinding | polishing of a glass material, especially surface grinding of the aluminosilicate glass substrate used for a cover glass, a hard disk, etc.

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

The base material 10 contains a heat resistant resin as a main component. As such a heat resistant resin, polycarbonate, biaxially stretched polyethylene terephthalate, polyimide, polyamide and the like can be mentioned. Among them, polycarbonate and biaxially stretched polyethylene terephthalate are preferable, and polycarbonate is more preferable. By using a polycarbonate or biaxially stretched polyethylene terephthalate as the substrate 10, the adhesion between the substrate 10 and the polishing portion 20a can be enhanced, and the substrate 10 and the polishing portion 20a can be hardly peeled off.

As a minimum of the glass transition temperature of substrate 10, 60 ° C is preferred, 80 ° C is more preferred, and 100 ° C is still more preferred. When the glass transition temperature of the substrate 10 is less than the above lower limit, the heat resistance is insufficient, and the substrate 10 is easily deformed by heat when forming the polishing portion 20 a. For this reason, there is a possibility that the adhesiveness of substrate 10 and polish part 20a may fall. On the other hand, the upper limit of the glass transition temperature of the substrate 10 is not particularly limited. For example, the glass transition temperature of the substrate 10 is 500 ° C. or less.

Also, the substrate 10 may have flexibility. Thus, since the base material 10 has flexibility, the said abrasives 1 track the surface shape of a to-be-cut body, and the contact area of a grinding surface and a to-be-cut body becomes large, a polishing rate can be raised. .

In addition, the process which improves adhesiveness, such as a chemical treatment, a corona treatment, and a primer process, may be performed on the surface of the base material 10.

The shape and size of the substrate 10 are not particularly limited, and for example, a square shape having one side of 140 mm to 160 mm, a disk of 200 mm to 2022 mm in diameter, an outer diameter of 200 mm to 2022 mm, and an inner diameter of 100 mm to 658 mm It can be annular or the like. In addition, the plurality of substrates 10 juxtaposed on a plane may be supported by a single support.

The lower limit of the average thickness of the substrate 10 is preferably 70 μm, more preferably 300 μm, and still more preferably 500 μm. On the other hand, as an upper limit of average thickness of substrate 10, 3000 micrometers is preferred and 2000 micrometers is more preferred. If the average thickness of the substrate 10 is less than the above lower limit, warpage of the substrate 10 may be easily generated when the polished portion 20 a is thick. Conversely, when the average thickness of the substrate 10 exceeds the above upper limit, the substrate 10 does not easily follow the surface shape of the workpiece, and the polishing rate may be reduced.

<Abrasive layer>
The polishing layer 20 includes abrasive grains 21, a binder 22 and fumed silica 23 in the polishing portion 20 a. In addition, the polishing unit 20a includes a filler (not shown).

(Abrasive)
Examples of the abrasive grains 21 include diamond abrasive grains, alumina abrasive grains, silica abrasive grains, ceria abrasive grains, silicon carbide abrasive grains and the like. Among them, diamond abrasives which are harder than other abrasives are preferable. By making the said abrasive grain 21 into a diamond abrasive grain, polishing power can be improved and a polishing rate can further be improved.

In addition, as a diamond of a diamond abrasive grain, a single crystal or a polycrystal may be sufficient, and the diamond by which Ni coating etc. were processed may be sufficient. Among them, single crystal diamond and polycrystalline diamond are preferable. Single crystal diamond is harder and more abrasive than other diamonds. In addition, polycrystalline diamond is apt to be easily cleaved in a microcrystalline unit constituting a polycrystalline, and it is difficult for the eye to crush to progress, so that the reduction in polishing rate is small even if polishing is performed for a long time.

The average particle size of the abrasive grains 21 is appropriately selected from the viewpoint of the polishing rate and the surface roughness of the object after polishing. The lower limit of the average particle size of the abrasive grains 21 is preferably 2 μm, more preferably 10 μm, and still more preferably 15 μm. On the other hand, as an upper limit of the average particle diameter of the abrasive grain 21, 150 micrometers is preferable, 125 micrometers is more preferable, and 100 micrometers is more preferable. If the average particle diameter of the abrasive grains 21 is less than the above lower limit, the polishing force of the polishing material 1 may be insufficient, and the polishing rate may be reduced. Conversely, if the average particle size of the abrasive grains 21 exceeds the above upper limit, the polishing accuracy may be reduced. Here, the "average particle size" refers to the 50% value (50% particle size, D50) of the 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, the upper limit of the content of the abrasive grains 21 is preferably 55% by volume, more preferably 45% by volume, and still more preferably 35% by volume. 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, when the content of the abrasive grains 21 exceeds the upper limit, the abrasive 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, resins are preferable from the viewpoint of adhesion to the substrate 10.

As said resin, resin, such as polyurethane, polyphenol, epoxy, polyester, cellulose, ethylene copolymer, polyvinyl acetal, polyacrylic acid and its salt, polyacrylic ester, polyvinyl alcohol, polyvinyl chloride, polyvinyl acetate, polyamide etc. Can be mentioned. Among them, polyacrylic esters, epoxy, polyesters and polyurethanes are preferred, which can easily ensure good adhesion to the substrate. The resin may be at least partially crosslinked.

Moreover, a silicate, a phosphate, a polyhydric-metal alkoxide etc. can be mentioned as said inorganic substance. Among them, silicates having high abrasive retention are preferred. Examples of such silicates include sodium silicate and potassium silicate.

The binder 22 may appropriately contain various assistants and additives such as a dispersant, a coupling agent, a surfactant, a lubricant, an antifoamer, and a colorant according to the purpose.

(Fumed silica)
Fumed silica 23 is a kind of dry silica and is fine particles (powder). The composition is amorphous silica or high purity glass.

The lower limit of the average primary particle size of the fumed silica 23 is preferably 5 nm, more preferably 7 nm. On the other hand, the upper limit of the average primary particle diameter of fumed silica 23 is preferably 100 nm, more preferably 60 nm, and still more preferably 40 nm. If the average primary particle diameter of the fumed silica 23 is less than the above lower limit, it tends to fly, which may make it difficult to handle the abrasive 1 at the time of production. On the contrary, when the average primary particle diameter of the fumed silica 23 exceeds the above upper limit, the thixotropic property by the fumed silica 23 at the time of manufacture of the said abrasives 1 runs short, and there exists a possibility that the grinding part 20a can not be made into a column.

As a minimum of content of fumed silica 23 in polish part 20a, 0.1 volume% is preferred and 1 volume% is more preferred. On the other hand, the upper limit of the content of fumed silica 23 is preferably 20% by volume, more preferably 10% by volume, and still more preferably 8% by volume. When the content of the fumed silica 23 is less than the above lower limit, the thixotropic property by the fumed silica 23 at the time of production of the abrasive 1 is insufficient, and there is a possibility that the polishing portion 20a can not be formed into a columnar shape. Conversely, when the content of fumed silica 23 exceeds the above upper limit, the abrasion of the polishing portion 20a is likely to proceed and the life of the abrasive material 1 may be reduced, or the adhesion between the substrate 10 and the polishing portion 20a is It may decrease.

(filler)
Examples of the 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 them, alumina is preferable because high polishing power is obtained.

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

The average particle size of the filler may be smaller than the average particle size of the abrasive grains 21. The lower limit of the ratio of the average particle size of the filler to the average particle size of the abrasive grains 21 is preferably 0.01, more preferably 0.05, and still more preferably 0.1. On the other hand, the upper limit of the ratio of the average particle size of the filler to the average particle size of the abrasive grains 21 is preferably 0.8, and more preferably 0.6. If the ratio of the average particle size of the filler to the average particle size of the abrasive grains 21 is less than the lower limit, the polishing rate may be reduced due to the insufficient effect of the filler on the elastic modulus of the binder 22. Conversely, if the ratio of the average particle size of the filler to the average particle size of the abrasive grains 21 exceeds the upper limit, the filler may inhibit the polishing force of the abrasive grains 21.

Although the content of the filler to the polishing portion 20a depends on the content of the abrasive grains 21, the lower limit of the content of the filler to the polishing portion 20a is preferably 15% by volume, and more preferably 30% by volume. preferable. On the other hand, as a maximum of content of the above-mentioned filler, 75 volume% is preferred, and 72 volume% is more preferred. If the content of the filler is less than the lower limit, the polishing rate may be reduced due to the insufficient effect of the filler on the elastic modulus improvement of the binder 22. Conversely, if the content of the filler exceeds the upper limit, the filler may inhibit the polishing force of the abrasive grains 21.

(Polishing section)
The polishing portion 20a is columnar. That is, the area of the bottom surface of the polishing portion 20a is 0.9 times to 1.5 times the area of the top surface of the polishing portion 20a, preferably 0.93 times to 1.2 times, more preferably 0.95. It is twice or more and 1.05 or less.

The plurality of polishing units 20 a have a block pattern that is regularly arranged in the same shape. The shape of the top surface of the polishing portion 20a is not particularly limited, but may be square as shown in FIG. 1, circular, polygonal or the like.

The lower limit of the average area of the top surface of the polishing unit 20a, preferably 1 mm ^2, 2 mm ² is more preferable. On the other hand, as a maximum of the average area of the top face of polish part 20a, 150 mm ² is preferred and 130 mm ² is more preferred. If the average area of the top surface of the polishing portion 20 a is less than the above lower limit, the polishing portion 20 a may be peeled off from the base material 10. On the other hand, if the average area of the top surface of the polishing portion 20a exceeds the above upper limit, the contact area of the polishing layer 20 to the cut object becomes large at the time of polishing, and the polishing rate may be reduced due to frictional resistance.

The lower limit of the area occupancy ratio of the plurality of polishing portions 20a to the entire polishing layer 20 is preferably 5%, and more preferably 10%. On the other hand, the upper limit of the area occupancy of the polishing portion 20a is preferably 60%, and more preferably 55%. If the area occupancy rate of the polishing portion 20a is less than the above lower limit, the pressure applied at the time of polishing is too concentrated on the narrow polishing portion 20a, and the polishing portion 20a may be peeled off from the base material 10. On the contrary, when the area occupancy of the polishing portion 20a exceeds the upper limit, the contact area of the polishing layer 20 to the workpiece at the time of polishing becomes large, and the polishing rate may be reduced due to the frictional resistance. In addition, "the area of the whole grinding | polishing layer" is the concept also including the area of the groove | channel of a grinding layer.

As a minimum of average thickness of polish part 20a, 300 micrometers is preferred and 500 micrometers is more preferred. On the other hand, as a maximum of average thickness of polish part 20a, 5000 micrometers is preferred and 3000 micrometers is more preferred. If the average thickness of the polishing portion 20a is less than the above lower limit, the life may be insufficient, or the shape stabilization effect of the polishing portion 20a at the time of production due to the inclusion of the fumed silica 23 of the polishing portion 20a may not be sufficiently expressed. There is. Conversely, if the average thickness of the polishing portion 20a exceeds the above upper limit, there is a possibility that the polishing portion 20a can not be formed into a columnar shape.

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

The average width of the grooves 20b is determined by the area and the area occupancy of the top surface of the polishing portion 20a, but the lower limit of the average width of the grooves 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, more preferably 8 mm. If the average width of the grooves 20b is less than the above-mentioned lower limit, there is a possibility that abrasive powder generated by polishing may clog the grooves 20b. Conversely, if the average width of the grooves 20b exceeds the above-described upper limit, the workpiece tends to fall into the grooves 20b at the time of polishing, and therefore, the workpiece may be damaged.

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

The adhesive used for the adhesive layer 30 is not particularly limited, and examples thereof include reactive adhesives, instant adhesives, hot melt adhesives, and adhesives that can be replaced.

As an adhesive used for this adhesive layer 30, an 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 and replaced from the support, and reuse of the abrasive 1 and the support becomes easy. Such an adhesive is not particularly limited, but, for example, acrylic adhesive, acrylic-rubber adhesive, natural rubber adhesive, synthetic rubber adhesive such as butyl rubber, silicone adhesive, polyurethane adhesive Agents and the like.

As a lower limit of the average thickness of adhesion layer 30, 0.05 mm is preferred and 0.1 mm is more preferred. On the other hand, as an upper limit of the average thickness of adhesion layer 30, 0.3 mm is preferred and 0.2 mm is more preferred. If the average thickness of the adhesive layer 30 is less than the above lower limit, the adhesive strength may be insufficient, and the abrasive 1 may be peeled off from the support. Conversely, if the average thickness of the adhesive layer 30 exceeds the above upper limit, there is a possibility that the workability may be deteriorated, for example, when the abrasive material 1 is cut into a desired shape due to the thickness of the adhesive layer 30 .

<Advantage>
In the polishing material 1, since the polishing portion 20 a contains fumed silica 23, the polishing portion 20 a can be formed in a columnar shape even with a thick polishing portion 20 a. For this reason, since it is not necessary to make the said grinding | polishing part 20a cone shape of the said abrasives 1, or to enlarge the area of the top face of the grinding | polishing part 20a, the grinding | polishing rate falls even if the grinding layer 20 wears. hard. Moreover, since the said base material 10 has heat resistant resin as a main component, the said abrasives 1 can suppress the fall of the adhesiveness of the base material 10 and the grinding | polishing part 20a because the grinding | polishing part 20a contains the fumed silica 23. . For this reason, with the said abrasives 1, the base 10 and the grinding | polishing part 20a do not separate easily. Therefore, the said abrasives 1 can thicken the grinding | polishing part 20a, suppressing the fall of a grinding | polishing rate.

[Method of producing abrasives]
The method for producing an abrasive shown in FIG. 3 mainly includes a preparation step S1, a polishing layer forming step S2, and an adhesive layer sticking step S3. By using the manufacturing method of the said abrasives, it is a polishing provided with the base material 10 shown, for example in FIG.1 and FIG.2, and the grinding layer 20 which is laminated on the surface side of this base material 10, and contains abrasive grain 21 and binder 22. The material 1 can be manufactured.

<Preparation process>
In the preparation step S1, a composition for an abrasive layer containing abrasive grains 21, a binder 22, and fumed silica 23 is prepared.

Specifically, a composition for an abrasive layer containing materials for forming the abrasive grains 21, the fumed silica 23, and the binder 22 is prepared as a coating liquid. The content of the abrasive grains 21 and the fumed silica 23 in the solid content is the content of the abrasive grains 21 and the fumed silica 23 of the polished portion 20a after production, respectively, so the content in the polished portion 20a is desired. Determine the amount of solids as appropriate to achieve the value of

Moreover, in order to control the viscosity and fluidity of the coating liquid, a diluent such as water or alcohol is added. By this dilution, a part of the abrasive grains 21 contained in the polishing portion 20 a can be made to project from the surface of the binder 22. That is, by adding the diluent, when the composition for polishing layer is dried in the polishing layer forming step S2, the thickness of the binder 22 is reduced, and the protrusion amount of the abrasive grains 21 can be increased. Therefore, this dilution makes it possible to develop a high polishing rate from the beginning of polishing.

<Abrasive layer formation process>
In the polishing layer forming step S2, the polishing layer 20 is formed by printing of the composition for a polishing layer prepared in the preparation step S1. The polishing layer forming step S2 includes a coating step and a drying step.

(Coating process)
In the coating step, the composition for a polishing layer is coated on the surface of the substrate 10. As the base material 10, one having a heat resistant resin as a main component is used.

Specifically, using the coating liquid prepared in the preparation step S1, the polishing layer 20 having a plurality of polishing portions 20a and grooves 20b disposed between the polishing portions 20a by printing on the surface of the substrate 10 is formed. Form. 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, etc. can be used.

As a mask for the said printing, the mask made from SUS or a fluorine resin is preferable. Since a mask made of SUS or a fluorine resin mask can be thickened, 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, it is good to adjust the amount of application of the above-mentioned constituent for polish layers so that average thickness of polish part 20a may be 300 micrometers or more, more preferably 500 micrometers or more at this coating process. The service life of the abrasive 1 can be improved by adjusting the coating amount so that the average thickness of the polishing portion 20a is equal to or more than the above lower limit. On the other hand, the upper limit of the average thickness of the polishing portion 20a adjusted in the coating step is not particularly limited, but is preferably 5000 μm and more preferably 3000 μm from the viewpoint of the manufacturing cost.

(Drying process)
In the drying step, the coating liquid (composition for polishing layer) after the coating step is dried by heating. The coating liquid is cured by the heat drying to form the polishing layer 20.

This drying step is performed with the mask removed. In the manufacturing method of the said abrasives, since the composition for abrasive layers contains the fumed silica 23, the fumed silica 23 gives thixotropy to the composition for abrasive layers. For this reason, the viscosity of the composition for polishing layers during heating can be appropriately controlled, and dripping can be suppressed. Therefore, even when the polishing portion 20a is thick, the columnar polishing portion 20a can be formed.

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

The heating time in the drying step depends on the heating temperature, but the lower limit of the heating time is preferably 2 hours, more preferably 2.5 hours. On the other hand, as an upper limit of the said heating time, 40 hours are preferable, 32 hours are more preferable, and 20 hours are further more preferable. If the heating time is less than the above lower limit, the composition for polishing layer may not be sufficiently cured, the amount of wear may be increased, and the life of the abrasive 1 may be shortened. Conversely, if the heating time exceeds the upper limit, the manufacturing efficiency may be reduced.

<Adhesive layer sticking process>
In adhesion layer sticking process S3, adhesion layer 30 is laminated on the back side of substrate 10. Specifically, for example, a tape-shaped adhesive layer 30 formed in advance is attached to the back surface of the substrate 10.

<Advantage>
In the method for producing an abrasive, the composition for the abrasive layer contains fumed silica 23. Therefore, when the abrasive layer 20 is formed by printing, the fumed silica 23 gives thixotropy to the composition for the abrasive layer, and the liquid is a liquid. Who can stop it. For this reason, even if it is the thick grinding | polishing part 20a, the columnar grinding | polishing part 20a can be formed by using the manufacturing method of the said abrasives. Moreover, in the manufacturing method of the said abrasives, since the base material 10 has heat resistant resin as a main component, even if it is a case where the composition for abrasive layers contains fumed silica 23, the base material 10 and the grinding | polishing part 20a are Hard to peel off. Therefore, by using the method for producing the abrasive, it is possible to produce an abrasive having a thick polishing portion 20a while suppressing a decrease in the polishing rate.

Other Embodiments
The present invention is not limited to the above embodiment, and can be implemented in various modifications and improvements in addition to the above embodiment.

Although the said embodiment demonstrated the case where a grinding | polishing part was block pattern shape, a grinding | polishing part is not limited to a block pattern shape. That is, the plurality of polishing portions may have different shapes or may be irregularly arranged. However, from the viewpoint of reducing the anisotropy of polishing, the polishing portion is preferably in the form of a block pattern.

Although the above-mentioned embodiment explained the case where a polish part included a filler, a filler is not an essential component, and the abrasives which have a polish part which does not contain a filler are also the intention of the present invention.

Although the above-mentioned embodiment explained the case where an abrasives has an adhesion layer, an adhesion layer is not an essential component and can be omitted. When the abrasive does not have the adhesive layer, the adhesive layer attaching step of the method of manufacturing the abrasive is omitted.

Alternatively, as shown in FIG. 4, the abrasive 2 may be provided with a support 40 laminated via the adhesive layer 30 on the back surface side and a second adhesive layer 31 laminated on the back surface side of the support 40. . When the abrasive 2 includes the support 40, the abrasive 2 can be easily handled.

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 40, the support 40 has flexibility, and the abrasive 2 follows the surface shape of the object to be cut, and the abrading surface and the object to be cut The polishing rate is further improved because the

The average thickness of the support 40 can be, for example, 0.5 mm or more and 3 mm or less. If the average thickness of the support 40 is less than the lower limit, the strength of the abrasive 2 may be insufficient. On the other hand, when the average thickness of the support 40 exceeds the upper limit, the support 40 may not be easily attached to the polishing apparatus, and the flexibility of the support 40 may be insufficient.

The same adhesive as the adhesive layer 30 can be used for the second adhesive layer 31. Further, the second adhesive layer 31 can have the same average thickness as the adhesive layer 30.

Hereinafter, the present invention will be described in more detail by way of examples and comparative examples, but the present invention is not limited to the following examples.

Example 1
Diamond abrasive grains ("SCMD-C12-22" from Sino Crystal Diamond, average particle size 16 μm), Alumina as filler (Al ₂ O ₃ , Pacific Random Co., Ltd. "LA 4000", average particle size 4 μm), fumes Desilica (“aerosil 200” by Aerosil Co., Ltd.) and epoxy resin (“JER 828” by Mitsubishi Chemical Corporation) as a binder are mixed, and the content of diamond abrasives in the solid content is 3% by volume, and the content of filler The amount was adjusted to 71% by volume and the content of fumed silica was 5% by volume to obtain a coating liquid.

A substrate (average thickness: 300 μm) mainly comprising polycarbonate, which is a heat resistant resin, was prepared as a substrate, and was coated on the surface of the substrate by printing using the above-mentioned coating liquid. As a printing pattern, a fluorine resin mask having an opening with a circular shape (average area of 28.27 mm ² ) with a diameter of 6 mm in plan view with an area occupancy of 44% and an average thickness of 1000 μm was used. The opening is in the form of a block pattern. Moreover, the coating amount was adjusted so that the average thickness of a grinding | polishing part might be 1000 micrometers. The coating liquid was cured by drying in an oven at 120 ° C. for 16 hours.

In addition, a hard vinyl chloride resin plate having an average thickness of 1 mm is used as a support for supporting the substrate and fixing it to the polishing apparatus, between the back surface of the substrate and the front surface of the support, and the back surface of the support A pressure-sensitive adhesive having an average thickness of 130 μm was attached to a surface plate of a polishing machine described later. A double-sided tape ("# 5605 HGD" from Sekisui Chemical Co., Ltd.) was used as the pressure-sensitive adhesive.

Thus, the abrasive of Example 1 was obtained.

Example 2
The abrasive of Example 2 was obtained in the same manner as in Example 1 except that the coating amount was adjusted so that the average thickness of the polishing portion was 300 μm.

[Example 3]
An abrasive of Example 3 was obtained in the same manner as in Example 1 except that a base material (average thickness: 75 μm) mainly comprising biaxially stretched polyethylene terephthalate, which is a heat resistant resin, was prepared as the base material.

Comparative Example 1
Example except that the coating liquid of Example 1 was adjusted so that the content of the diamond abrasive grains in the solid content was 3% by volume and the content of the filler was 76% by volume without containing fumed silica The abrasives of Comparative Example 1 were obtained in the same manner as in 1.

Comparative Example 2
An abrasive of Comparative Example 2 was obtained in the same manner as Comparative Example 1 except that a substrate (average thickness: 300 μm) mainly composed of biaxially stretched polyethylene terephthalate was prepared as the substrate.

Comparative Example 3
An abrasive of Comparative Example 3 was obtained in the same manner as Comparative Example 1 except that an aluminum plate (average thickness: 300 μm) was prepared as a substrate.

Comparative Example 4
An abrasive of Comparative Example 4 was obtained in the same manner as Example 1, except that an aluminum plate (average thickness: 300 μm) was prepared as a substrate.

[Evaluation]
With respect to the abrasives of Examples 1 to 3 and Comparative Examples 1 to 4, the life of the abrasives, the peeling between the substrate and the polishing portion, and the dripping during printing were evaluated based on the following judgment criteria. The results are shown in Table 1.

<Abrasive Life>
The life of the abrasive is considered to be determined by the average thickness of the polishing portion. Therefore, the following judgment criteria were used.
A: The average thickness of the polished portion is 1000 μm, and the life is high.
B: The average thickness of the polished portion is 300 μm, and the life is slightly short.

<Peeling of base material and polishing part>
After bending the obtained abrasives, it was judged by visual observation whether or not peeling between the base and the polishing portion had occurred.
A: Peeling between the substrate and the polishing portion is observed.
B: Peeling between the substrate and the polishing part is not observed.

<Drip on printing>
If dripping occurs during printing, deformation occurs to the printed pattern after drying and curing. It was judged by visual observation of the obtained abrasives whether or not this deformation occurred.
A: No deformation of printed pattern observed after drying and curing.
B: Deformation of printed pattern is observed after drying and curing.

In Table 1, "PC" of the substrate is polycarbonate, "PET" is biaxially oriented polyethylene terephthalate, and "Al" is an aluminum plate.

From Table 1, in the abrasives of Examples 1 to 3, neither peeling between the base and the polishing portion nor deformation of the print pattern after drying and curing due to liquid dripping is recognized regardless of the thickness of the polishing portion. On the other hand, in the abrasives of Comparative Examples 1 to 3, deformation of the printed pattern after drying and curing due to dripping is recognized, and in the abrasive of Comparative Example 4, peeling between the base and the polishing portion is observed.

Since the abrasives of Comparative Examples 1 to 3 do not contain fumed silica, it is considered that dripping occurred and deformation of the print pattern after drying and curing was observed. In the polishing material of Comparative Example 4, although the deformation of the printed pattern after drying and curing due to dripping could be suppressed by containing fumed silica, peeling between the substrate and the polishing portion occurs because the substrate is an aluminum plate. It is thought that

From the above results, when fumed silica is contained in the polishing part and the main component of the base material is a heat resistant resin, dripping can be suppressed and a thick columnar polishing part can be formed. It is understood that the life can be extended while suppressing the decrease of

With the abrasive of the present invention and the abrasive produced by the method of producing an abrasive of the present invention, the thickness of the polishing portion can be increased while suppressing a decrease in the polishing rate. Therefore, the abrasives of the present invention and the abrasive produced by the method of producing an abrasive of the present invention can have a long life while exhibiting a stable polishing rate.

1, 2 Abrasive material 10 Substrate 20 Abrasive layer 20a Abrasive portion 20b Groove 21 Abrasive particle 22 Binder 23 Fumed silica 30 Adhesive layer 31 Second adhesive layer 40 Support

Claims

An abrasive comprising: a substrate; and an abrasive layer laminated on the surface side of the substrate and containing an abrasive and a binder,
The polishing layer has a plurality of columnar polishing portions,
The polishing section contains fumed silica,
The abrasive which the said base material has heat resistant resin as a main component.
The abrasive according to claim 1, wherein the content of the fumed silica in the polishing portion is 0.1% by volume or more and 20% by volume or less.
The abrasives according to claim 1 or 2, wherein an average thickness of the polishing portion is 300 μm or more and 5000 μm or less.
The abrasive according to claim 1, 2 or 3, wherein the substrate is polycarbonate or biaxially stretched polyethylene terephthalate.
What is claimed is: 1. A method of producing an abrasive comprising: a base material; and an abrasive layer laminated on the surface side of the base material and containing abrasive grains and a binder,
Forming a polishing layer by printing the polishing layer composition,
The polishing layer has a plurality of columnar polishing portions,
The above composition for polishing layer contains fumed silica,
The manufacturing method of the abrasives in which the above-mentioned base material makes heat resistant resin the main ingredients.