Abstract:
An abrasive article having a multi-directional abrasion protrusion according to an exemplary embodiment of the present invention includes a flexible base substrate, and a plurality of abrasion protrusions integrally molded with the base substrate and having at least three sides forming a triangle, in which a plurality of abrasion protrusions has a directional property by grouping. 
     According to this constitution, loading resistance and durability are excellent, there are no attachment materials attached to an abraded surface in the case where a flat surface is abraded, abrasion can be efficiently and evenly performed in a predetermined shape even though abrasion particles are not enlarged to perform abrasion or abrasion is not repeated several times by using particulates, and abrasion performance can be improved.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority to and the benefit of Korean Patent Application No. 10-2012-0042266 filed in the Korean Intellectual Property Office on Apr. 23, 2012, the entire contents of which are incorporated herein by reference. 
       BACKGROUND OF THE INVENTION 
       [0002]    (a) Field of the Invention 
         [0003]    The present invention relates to an abrasive article having a multi-directional abrasion protrusion, and more particularly, to an abrasive article having a multi-directional abrasion protrusion, in which grinding performance is improved by providing various directional properties to an abrasion protrusion pattern (the degree of freedom is increased). 
         [0004]    (b) Description of the Related Art 
         [0005]    Recently, an abrasion method using fluidic abrasion slurry has been replaced with a solid abrasive article because problems that a large amount of slurry is required, separate equipment for agitation, treatment, discarding, and the like is required to manufacture slurry with a uniform concentration, and the abrasion method is not environmentally-friendly have been on the rise. 
         [0006]    However, the solid abrasive article has problems in that defects or flaws may remain which does not provide predetermined transparency to articles such as glass and progress traces and the like remain during abrasion, and particularly, a problem in that a lot of time is required in order to obtain a predetermined effect as compared to the fluidic abrasion slurry. 
         [0007]    As illustrated in  FIG. 1A , a ultraprecision finishing abrasive article  1  formed of a solid, in which abrasion protrusions  20  having a predetermined 3D structure shape are uniformly applied on a surface of a substrate  10 , is used in order to solve the problems. 
         [0008]    However, it can be seen that in the solid abrasive article, as illustrated in  FIG. 1B , in the case where the abrasion protrusion  20  has a quadrangular pyramid shape where a base portion  21  is quadrangular, when abrasion is performed in a direction (arrow direction) that is vertical to lateral sides  23  and  25  of a triangle extending from each base portion  21 , since the largest areas  23   a  and  25   a  and slopes  23   b  and  25   b  are ensured, abrasion performance is best. 
         [0009]    There are problems in that since the abrasion protrusions  20  are formed of abrasion particles at a minute level, abrasion dust collects between the abrasion protrusions  20  after abrasion, and since liquid used as a coolant and a lubricant does not sufficiently fulfill a function between the abrasion protrusions and a glass board, a portion of an abrasion material forming the abrasion protrusions is attached to a surface of the glass board after abrasion and abrasion performance is rapidly reduced. 
         [0010]    A way to space the abrasion protrusion  20  and the abrasion protrusion  20  apart from each other is proposed in order to solve the problems. 
         [0011]    However, in this case, there are problems in that a density of the abrasion protrusion  20  on a substrate is reduced to reduce grinding performance by a reduction in density, and in the case where a form of a general abrasive article, for example, an abrasion tape, is used, if considering that the form is used by performing rotation in one direction, many spaces where abrasion is not performed are formed. 
         [0012]    Further, in the case where the abrasion material is attached to a surface of a body to be ground, washing or abrasion is performed while pushing with strong force is performed in a final finishing step, but there is a problem in that the abrasion material cannot be removed by uniform abrasion protrusions  20  having a constant size, and thus abrasion is repeated several times by the abrasive article  1  having larger abrasion protrusions  20 . 
         [0013]    The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art. 
       SUMMARY OF THE INVENTION 
       [0014]    The present invention has been made in an effort to provide an abrasive article having a multi-directional abrasion protrusion, in which loading resistance and durability are excellent, there are no attachment materials attached to an abraded surface in the case where a flat surface is abraded, abrasion is efficiently and evenly performed in a predetermined shape even though abrasion particles are not enlarged to perform abrasion or abrasion is not repeated several times by using particulates, and abrasion performance is improved. 
         [0015]    An exemplary embodiment of the present invention provides an abrasive article having a multi-directional abrasion protrusion including: a flexible base substrate, and a plurality of abrasion protrusions integrally molded with the base substrate and having at least three sides forming a triangle. 
         [0016]    A plurality of abrasion protrusions has a directional property by grouping. 
         [0017]    According to an exemplary embodiment of the present invention, it is possible to provide an abrasive article having a multi-directional abrasion protrusion, in which loading resistance and durability are excellent, there are no attachment materials attached to an abraded surface in the case where a flat surface is abraded, abrasion can be efficiently and evenly performed in a predetermined shape even though abrasion particles are not enlarged to perform abrasion or abrasion is not repeated several times by using particulates, and abrasion performance is improved. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0018]      FIG. 1A  is a perspective view of a general abrasive article. 
           [0019]      FIG. 1B  is a top plan view of  FIG. 1A . 
           [0020]      FIG. 2A  is a top plan view of an abrasion protrusion of an abrasive article according to an exemplary embodiment of the present invention. 
           [0021]      FIG. 2B  is a top plan view of a grouped abrasion protrusion of the abrasive article according to the exemplary embodiment of the present invention. 
           [0022]      FIG. 3  is a top plan view of the abrasive article according to the exemplary embodiment of the present invention. 
           [0023]      FIG. 4  is a graph comparing an abrasion amount of the abrasive article according to the exemplary embodiment of the present invention and an abrasion amount of an abrasive article in the related art. 
           [0024]      FIG. 5  is a top plan view of an abrasive article according to a modified exemplary embodiment of the present invention. 
           [0025]      FIG. 6  is a top plan view of an abrasive article according to another modified exemplary embodiment of the present invention. 
           [0026]      FIGS. 7A and 7B  are top plan views of an abrasive article according to yet another modified exemplary embodiment of the present invention. 
           [0027]      FIGS. 8A and 8B  are top plan views of an abrasive article according to still another modified exemplary embodiment of the present invention. 
           [0028]      FIG. 9  is a top plan view of an abrasive article according to a further modified exemplary embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
       [0029]    Preferable exemplary embodiments of the present invention will be described in more detail with reference to the accompanying drawings, but a known technology portion will be omitted or compressed for briefness of the description. 
         [0030]      FIG. 2A  is a top plan view of an abrasion protrusion of an abrasive article according to an exemplary embodiment of the present invention,  FIG. 2B  is a top plan view of a grouped abrasion protrusion of the abrasive article according to the exemplary embodiment of the present invention,  FIG. 3  is a top plan view of the abrasive article according to the exemplary embodiment of the present invention, and  FIG. 4  is a graph comparing an abrasion amount of the abrasive article according to the exemplary embodiment of the present invention and an abrasion amount of an abrasive article in the related art. 
         [0031]    Referring to  FIG. 2A , an abrasion protrusion  120  uniformly applied on a surface of an abrasion substrate  110  of an abrasive article  100  according to the exemplary embodiment of the present invention may be integrally formed with the abrasion substrate  110 , and may be formed of a tetrahedron having four sides forming a triangle. 
         [0032]    An abrasion particle typically has a particle size in the range of about 0.1 to 1500 μm, and includes molten aluminum oxide including brown aluminum oxide, heat treated aluminum oxide, and white aluminum oxide, ceramic aluminum oxide, green silicon carbide, silicon carbide, chromia, alumina zirconia, diamond, iron oxide, ceria, cube boron nitride, boron carbide, garnet, and a combination thereof. 
         [0033]    The term “abrasion particle” means that single abrasion particles are bound to each other to form the abrasion protrusion, and the abrasion particles are dispersed in an organic binding agent to form the abrasion protrusion. The binding agent is induced from a binding agent precursor including an organic polymerizable resin. 
         [0034]    When the abrasive article of the present invention is manufactured, the binding agent precursor is exposed to an energy source helping initiation of a polymerization or curing process. Examples of the energy source include heat energy and radiation energy, and the latter includes an electronic beam, ultraviolet rays, and visible rays. A resin is polymerized to be converted into the binding agent where the binding agent precursor is agglomerated during the polymerization process. Abrasion coating is formed when the binding agent precursor is agglomerated. 
         [0035]    Typical and favorable examples of the organic resin include a phenollic resin, a urea-formaldehyde resin, a melamine formaldehyde resin, acrylated urethane, acrylated epoxy, an ethylene unsaturated compound, an aminoplaste derivative having a branched unsaturated carbonyl group, an isocyanurate derivative having at least one branched acrylate group, an isocyanate derivative having at least one branched acrylate group, vinyl ether, an epoxy resin, and a mixture and a combination thereof. 
         [0036]    A grinding aid may be added to improve chemical and physical characteristics of the abrasive article, and particularly, the grinding aid may be used to 1) improve friction between the abrasion particles and operation workpieces to be abraded, 2) prevent the abrasion particle from being “capped”, that is, prevent metal particles from being welded to upper portions of the abrasion particles (in the case of the metal workpieces), 3) reduce an interface temperature between the abrasion particles and the workpieces, 4) reduce required grinding force, or 5) prevent the metal workpieces from being oxidized, thus increasing a use life-span of the abrasive article. 
         [0037]    A selective additive such as a filler, fibers, a lubricant, a wetting agent, a thixotropic material, a surfactant, a dye, a pigment, an antistatic agent, a coupling agent, a plasticizer, and a suspending agent may be further included. The amount of the aforementioned materials is selected so as to provide a desired characteristic. The use thereof may affect corrosivity of the abrasion protrusion. In some cases, the additive may serve to much well corrode the abrasion protrusion, thus discharging blunt abrasion particles and exposing new abrasion particles. 
         [0038]    As illustrated in  FIG. 2A , the base portion  121  of the abrasion protrusion  120  may have three sides or four sides, and is constituted by three sides in the exemplary embodiment of the present invention, and is constituted so that a lateral side  123  of the abrasion protrusion  120  is gradually reduced in a height direction. 
         [0039]    If the abrasion protrusion  120  is constituted by the tetrahedron, when a body to be ground is positioned at the corner of the abrasion protrusion  120  during grinding, largest pressure is provided at an angle at which grinding efficiency is highest, herein, at a right angle to each side to perform abrasion well, and thus highest grinding efficiency or washing efficiency may be exhibited. 
         [0040]    Three angles at which grinding efficiency is high, for example, 55°, 172.5°, and 297.5° based on one corner may be provided to one abrasion protrusion  120 . 
         [0041]    Further, the side of the abrasion protrusion  120  may be constituted to be gradually reduced in a height direction, thus providing a secondary abrasion protrusion along the non-uniform abrasion side and more easily releasing the abrasion protrusion from a manufacturing tool when the abrasive article  100  as described later is manufactured. 
         [0042]    Meanwhile, as illustrated in  FIG. 2B , the abrasive article  100  according to the exemplary embodiment of the present invention may have a multi-directional property by grouping a plurality of abrasion protrusions  120 ,  130  . . . , for example, six abrasion protrusions  120 ,  130  . . . to constitute a hexahedron. 
         [0043]    In this case, a more larger cross-sectional area  125   a  may be provided by two lateral sides  123  and  133  when the first abrasion protrusion  120  and the second abrasion protrusion  130  are grouped and abrasion is performed in one direction using the hexahedron by the grouped abrasion protrusion  120 , as compared to a cross-sectional area  123 A used to perform abrasion in a direction that is vertical to one lateral side  123  of the abrasion protrusion  120  by one abrasion protrusion  120 . 
         [0044]    Accordingly, two or more different abrasion sides may be provided by using one abrasive article to obtain an effect of using two or more different abrasive articles, increase abrasion performance, and rapidly perform abrasion as compared to the related art. 
         [0045]    Meanwhile, according to the exemplary embodiment of the present invention, as illustrated in  FIG. 3 , six angles at which grinding efficiency is high, for example, 55°, 172.5°, 297.5°, 235°, 352.5°, and 117.5° at which grinding or washing efficiency is highest based on one corner, may be provided by arranging the tetrahedral abrasion protrusions  120  in a forward direction so as to allow the abrasion protrusions to be adjacent to each other, and repeatedly disposing the tetrahedral abrasion protrusions  130  disposed in a backward direction between the adjacent tetrahedral abrasion protrusions  120 . 
         [0046]    That is, abrasion may be performed in almost all directions by the abrasive article  100  having the grouped first and second abrasion protrusions  120  and  130  even though a separate abrasive article is not used in order to remove defects and the like formed during abrasion, and, generally, if there may be at least five separate abrasion protrusions per cm 2 , at least ten abrasion protrusions may be provided per cm 2  according to the exemplary embodiment of the present invention, and thus grinding efficiency may be increased as compared to the related art. 
         [0047]    Further, it can be seen that in the first abrasion protrusion  120  abraded in one direction, since a space in which abrasion is not performed may occur, surface defects of the body to be ground cannot be removed or grinding traces may remain, but a more flat surface may be obtained by performing removal by the second abrasion protrusion  130  disposed in a backward direction, thus removing the surface defects of the body to be ground and the grinding traces. 
         [0048]    Further, a multi-directional property may be further provided by rotating the grouped abrasion protrusions  120  and  130  at 90° in one direction and placing the abrasion protrusions end to end. 
         [0049]    As illustrated in  FIG. 4 , it can be seen that an abrasion time of about 7 mins and up to 15 mins is required to abrade the body having the size of 50 cm×50 cm to be ground by the abrasive article according to the exemplary embodiment of the present invention while about 25 mins or more are required to abrade the same body to be ground by an abrasive article in the related art in order to provide the abrasion side under the same condition through a microscope, and thus abrasion efficiency of two times or more is ensured. 
         [0050]    Now, an abrasive article according to another exemplary embodiment of the present invention will be described in detail with reference to  FIGS. 5 to 9 . 
         [0051]      FIG. 5  is a top plan view of an abrasive article according to a modified exemplary embodiment of the present invention,  FIG. 6  is a top plan view of an abrasive article according to another modified exemplary embodiment of the present invention,  FIG. 7  is a top plan view of an abrasive article according to yet another modified exemplary embodiment of the present invention, and  FIG. 8  is a top plan view of an abrasive article according to still another modified exemplary embodiment of the present invention. 
         [0052]    It can be seen that all abrasive articles provide an increased initial cutting rate (measured by a mass per a cycle), the cutting rate minimally deteriorates in each continuous abrasion cycle, and grinding efficiency is increased as compared to the related art. 
         [0053]    The abrasion protrusion illustrated in  FIGS. 5 to 8  may be manufactured by the same method of manufacturing the abrasive article as described below, and since the abrasion particle and the binding agent can be used like the related art, a detailed description thereof will be omitted. 
         [0054]    As illustrated in  FIG. 5 , an abrasion protrusion  220  according to the exemplary embodiment of the present invention has a rectangular base portion  221 , and four lateral sides  223  and  224  extending from four lateral sides of the base portion  221  to a vertex  222 . 
         [0055]    Since lateral sides  223   a  and  224   a  of the base portion  221  have different lengths, the abrasion protrusion  220  according to the exemplary embodiment of the present invention may have a first flat side  223   a  in a direction that is vertical to the first lateral side  223  in a first direction and a second flat side  224   a  in a direction that is vertical to the second lateral side  224  in a second direction to increase the multi-directional property or the degree of freedom by one abrasive article, thus obtaining an effect of two abrasive articles. 
         [0056]    As illustrated in  FIG. 6 , an abrasive article  300  according to another exemplary embodiment of the present invention is constituted by disposing a hexagonal base portion  321 , a first abrasion protrusion  320  having six lateral sides  323  and  325  extending from six lateral sides  321   a  of the base portion  321  to vertexes  322 , and a second abrasion protrusion  330  including any one of the six lateral sides  321   a  of the base portion  321  of the first abrasion protrusion  320 , in which lengths of the residual lateral sides are different from a length of any one of the six lateral sides of the base portion  321  of the first abrasion protrusion  320 , to connect the first abrasion protrusion and the second abrasion protrusion to each other. 
         [0057]    Since at least two of the lateral sides of the base portion  321  have different lengths, the abrasive article  300  according to the exemplary embodiment of the present invention may have a plurality of first flat sides  323   a  having different abrasion sides in a direction that is vertical to a first lateral side  323  in a first direction and a plurality of second flat sides  333   a  having different areas of the abrasion sides in a direction that is vertical to a second lateral side  333  in a second direction to increase the multi-directional property or the degree of freedom by one abrasive article, thus obtaining an effect of at least two or more abrasive articles. 
         [0058]    As illustrated in  FIG. 7A , an abrasive article  400  according to a modified exemplary embodiment of the present invention may provide a multi-directional property by, in an abrasion protrusion  420  where base portions  421  are triangles having the same area, disposing an n-th abrasion protrusion in a forward direction and an n+1-th abrasion protrusion in a backward direction in an n-th column, and disposing directions of the n-th abrasion protrusions of the n-th column and an n+1-th column to allow the directions to be symmetrical to each other. 
         [0059]    In this case, a plurality of abrasion protrusions  420  may be spaced apart from each other by a pitch p, and it is preferable that the pitch be set so that an area of the base portion  421  of the abrasion protrusion  420  is 90% or more based on an entire area of the abrasive article in order to increase abrasion efficiency. 
         [0060]    As illustrated in  FIG. 7B , an abrasive article  400 ′ according to a modified exemplary embodiment of the present invention may provide a multi-directional property to the abrasive article  400  by, in an abrasion protrusion  420 ′ where base portions  421 ′ are squares having the same area, rotating the square abrasion protrusion  420 ′ at 90° to dispose the abrasion protrusion in an n-th column and rotating the square abrasion protrusion  420 ′ at 90° to dispose the abrasion protrusion in an n+1-th column so that a first lateral side of an n-th abrasion protrusion of the n-th column faces three n-th lateral sides of the n+1-th column, thus offsetting the abrasion protrusion of the n-th column and the abrasion protrusion of the n+1-th column. According to this constitution, when the abrasion protrusion of the n-th column is abraded in one direction by the abrasive article  400 ′, grinding efficiency may be increased by removing abrasion traces occurring in the body to be ground by the abrasion protrusion of the n+1-th column. 
         [0061]    In this case, a plurality of abrasion protrusions  420 ′ may be spaced apart from each other by a pitch p, and it is preferable that the pitch be set so that an area of the base portion  421 ′ of the abrasion protrusion  420 ′ is 90% or more based on an entire area of the abrasive article in order to increase abrasion efficiency and increase a loading deterioration property. 
         [0062]    Referring to  FIG. 8A , an abrasive article  500  according to another exemplary embodiment of the present invention may increase grinding efficiency by, in the case where an abrasion protrusion  520  having a square base portion  521  is arranged in an n-th column, constituting an n-th abrasion protrusion  530  of an n+1-th column to be offset to the n-th abrasion protrusion  520  of the n-th column, and preferably disposing the n-th abrasion protrusion  530  of the n+1-th column to start on a perpendicular line of the n-th abrasion protrusion  520  of the n-th column, thus removing abrasion traces occurring in the body to be ground when the abrasion protrusion of the n-th column is abraded by the abrasion protrusion of the n+1-th column. Vertexes  522  and  532  of the first abrasion protrusion  520  and the second abrasion protrusion  530  are constituted to form a zigzag pattern. 
         [0063]    As illustrated in  FIG. 8B , an abrasive article  500 ′ according to another exemplary embodiment of the present invention may provide a multi-directional property by continuously disposing a first grouped abrasion protrusion  520 ′ and a second grouped abrasion protrusion  530 ′. 
         [0064]    Referring to  FIG. 9 , an abrasive article  600  according to another exemplary embodiment of the present invention is constituted by disposing a first abrasion protrusion  620  having at least one of a first shape, a first surface area, and a first directional property, and a second abrasion protrusion  630  having at least one of a second shape, a second surface area, and a second directional property to be grouped. 
         [0065]    In this case, a plurality of abrasion protrusions  620  and  630  may be spaced apart from each other by a pitch p, and it is preferable that the pitch be set so that an area of base portions  610  of the abrasion protrusions  620  and  630  is 90% or more based on an entire area of the abrasive article in order to increase abrasion efficiency and increase a loading deterioration property. 
         [0066]    While this invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. 
       &lt;Description of Symbols&gt; 
       [0067]      100 ,  200 ,  300 ,  400 ,  500 ,  600 : Abrasive article 
         [0068]      110 ,  210 ,  310 ,  410 ,  510 ,  610 : Base portion 
         [0069]      120 ,  130 ,  220 ,  230 ,  320 ,  330 ,  420 ,  520 ,  620 ,  630 : Abrasion protrusion