CN114901430A

CN114901430A - Coated abrasive article and method of making a coated abrasive article

Info

Publication number: CN114901430A
Application number: CN202080085085.1A
Authority: CN
Inventors: 刘玉阳; 迈克尔·J·安嫩; 雅伊梅·A·马丁内斯; 李军廷; 张靖; 丹尼尔·A·比利希
Original assignee: 3M Innovative Properties Co
Current assignee: 3M Innovative Properties Co
Priority date: 2019-12-09
Filing date: 2020-12-07
Publication date: 2022-08-12
Also published as: US20230001544A1; WO2021116883A1; EP4072780A1

Abstract

A coated abrasive article is provided. The coated abrasive article includes a backing having opposed first and second major surfaces. The coated abrasive article also includes a make coat bonded to the first major surface. The coated abrasive article also includes abrasive particles that are directly bonded to the make coat. The abrasive particles are at least partially embedded in the make coat. The coated abrasive article also includes a size layer directly bonded to the make layer and the abrasive particles. One of the make coat and the size coat includes a patterned coating.

Description

Coated abrasive article and method of making a coated abrasive article

Background

Coated abrasive articles are widely used in abrading, dressing, or grinding various materials and surfaces during article manufacturing procedures. Generally, coated abrasive articles include a backing, a first layer of cured resin adhesive (make layer) applied to one major surface of the backing, abrasive particles, a second layer of cured resin adhesive (size layer), and optionally a third layer of cured resin adhesive (supersize layer). In some cases, grinding aids are used to improve grinding performance and are typically used as additives to form at least one of the aforementioned resin binder layers.

Drawings

Fig. 1A is a schematic illustration of an exemplary coated abrasive article according to the present disclosure.

FIG. 1B is a top view of an exemplary coated abrasive article.

Fig. 2A and 2B illustrate a method and results of pattern coating an abrasive article according to embodiments described herein.

FIG. 3 is a diagrammatic view of a method of making a patterned coated abrasive article according to embodiments described herein.

Fig. 4A-4D illustrate a patterned coated abrasive article according to embodiments described herein.

Fig. 5 illustrates a method of using a patterned coated abrasive article according to embodiments described herein.

Fig. 6 illustrates a coated abrasive article according to embodiments described herein.

Fig. 7A-7I illustrate coated abrasive articles made according to an embodiment.

Repeat use of reference characters in the present specification and drawings is intended to represent same or analogous features or elements of the disclosure. It should be understood that numerous other modifications and embodiments can be devised by those skilled in the art that will fall within the scope and spirit of the principles of this disclosure. The figures may not be drawn to scale.

Detailed Description

Coated abrasive articles are known in the art and typically include abrasive particles embedded in a make coat on a backing and coated with a size coat that reduces the dusting (shelling) of the abrasive particles from the backing. A supersize layer or other functional layers (including functional layers as well as a primer layer or laminate layer) may also be added to add functionality and/or alter parameters of the coated abrasive article.

Typically, the patterned coated abrasive article exhibits better abrading efficiency than a non-patterned coated abrasive article. This may be due to more efficient removal of swarf from the workpiece, judicious engineering of the grinding area, or facilitation of the effect of lubricants and/or grinding aids on the working surface.

As used herein, a "pattern" on a coated abrasive article refers to the intentional placement of material on a backing such that a portion of the backing or a portion of a previous layer remains uncoated. Thus, the patterned primer coating covers some but not all of the backing, such that portions of the backing remain uncovered. Similarly, a patterned layer of abrasive particles can result in some, but not all, of the make coat being coated with abrasive particles. The pattern includes a deliberate design with or without repeating units. The pattern may extend from the center of the abrasive disc or the central axis of the abrasive belt to the edge of the abrasive disc or the abrasive belt. Patterned coatings are intended to include any suitable method of forming well-defined areas of a given material coating as well as open areas without a given material coating. Thus, the patterned abrasive region can be designed independently of any pattern present on the fabric substrate to optimize both abrasive performance, dust removal, and antiloading characteristics. The pattern may comprise lines, swirls, polygons, letters, or numbers. In addition, other textual or product information may also be provided on the coated abrasive article. The pattern may also include a color such that portions of the final coated abrasive article have a first color and portions of the final coated abrasive article have a second color.

It is also known in the art that abrasive particles can be pattern coated and/or aligned on the surface of the backing. In some embodiments, patterned dispensing can be achieved using an alignment tool by methods similar to those described in PCT patent application publication 2016/205133(Wilson et al), 2016/205267(Wilson et al), 2017/007703(Wilson et al), 2017/007714(Liu et al). Transfer coating using a tool with patterned cavities can be similar to the transfer coating described in U.S. patent application publication 2016/0311081A1(Culler et al). In some embodiments, the abrasive particles may be applied to the make layer through a patterned mesh or screen.

Alignment of the abrasive particles may be accomplished using electrostatic or magnetic coatings, as described in the following applications: PCT patent application publications WO2018/080703(Nelson et al), WO2018/080756(Eckel et al), WO2018/080704(Eckel et al), WO2018/080705(Adefris et al), WO2018/080765(Nelson et al), WO2018/080784(Eckel et al), WO2018/136271(Eckel et al), WO2018/134732(Nienaber et al), WO2018/080755(Martinez et al), WO2018/080799(Nienaber et al), WO2018/136269(Nienaber et al), WO2018/136268(Jesme et al), WO2019/207415(Nienaber et al), WO2019/207417 (WO 201kel et al), WO2019/207416(Nienaber et al), and provisional applications for U.S. 2019/6314, U.S. 2019/2019, U.S. 2019, provisional application for provisional application number 7, U.S. 2019/2019, U.S. 2019, and provisional application number 587, and provisional application number 23, U.S. 2019, U.S. 2019/639.

The terms "cured", "curing" and "curable" refer to the joining together of polymer chains by covalent chemical bonds (typically by cross-linking molecules or groups) to form a network. Thus, in the present disclosure, the terms "cured" and "crosslinked" may be used interchangeably.

Fig. 1A and 1B show views of a coated abrasive article according to embodiments described herein.

Referring now to fig. 1A, coated abrasive article 100 includes backing 110 having a first major surface 112 and a second major surface 114 opposite first major surface 112. A make layer 120 is disposed on and bonded to the first major surface 112. Abrasive particles 130 and abrasive particles 130 are bonded to the make layer 120. The size layer 140 is disposed over and bonded to the make layer 120 and abrasive particles 130. An optional supersize layer or other functional layer is disposed over and bonded to size layer 140.

Referring now to FIG. 1B, one exemplary form of a coated abrasive article is a coated abrasive disk 150. However, other coated abrasive articles, such as abrasive belts, are also contemplated.

Exemplary suitable materials for the backing include polymeric films, metal foils, woven fabrics, knitted fabrics, paper, vulcanized fiber, nonwoven fabrics, foams, wire meshes, nets, laminates, combinations thereof and treated versions thereof. The coated abrasive article may be in the form of a sheet, disc, belt, pad, or roll. The backing may be rigid, semi-rigid, or flexible. In some embodiments, the backing should be sufficiently flexible to allow the coated abrasive article to be formed into a loop to make an abrasive belt that can be run on a suitable grinding apparatus. For applications requiring the stiffness of the backing, flexible backings may also be used by securing them to rigid support pads mounted to the grinding tool. For hands-free grinding applications where hardness and cost are considerations, vulcanized fiber backings are generally preferred. In some embodiments, the backing may be circular and may comprise a continuous, uninterrupted disc, while in other embodiments it may have a central spindle hole for mounting. Likewise, the circular backing may be flat, or it may have a recessed central hub, such as a recessed central disk of type 27. In some embodiments, the backing has mechanical or adhesive fasteners securely attached to the major surface opposite the abrasive layer.

The make layer, size layer, and optional supersize layer comprise resin binders that may be the same or different. Exemplary suitable binders can be prepared from corresponding binder precursors such as thermally curable resins, radiation curable resins, and combinations thereof.

The binder precursor (e.g., make layer precursor and/or size layer precursor) can comprise, for example, glues, phenolic resins, aminoplast resins, urea-formaldehyde resins, melamine-formaldehyde resins, urethane resins, polyfunctional (meth) acrylates that can polymerize in a free radical manner (e.g., aminoplast resins having pendant α, β -unsaturated groups, acrylated urethanes, acrylated epoxy resins, acrylated isocyanurates), epoxy resins (including bis-maleimides and fluorene-modified epoxy resins), isocyanurate resins, and mixtures thereof. Of these, phenolic resins are preferred, especially when used in conjunction with a vulcanized fiber backing.

Generally, phenolic resins are formed by the condensation of phenol and formaldehyde and are generally classified as resole or novolak phenolic resins. The novolac phenolic resin is acid catalyzed and has a formaldehyde to phenol molar ratio of less than 1: 1. Resol/resol phenolic resins may be catalyzed with a basic catalyst and have a formaldehyde to phenol molar ratio of greater than or equal to one, typically between 1.0 and 3.0, so that pendant methylol groups are present. Suitable basic catalysts for catalyzing the reaction between the aldehyde and phenol components of the resole resin include sodium hydroxide, barium hydroxide, potassium hydroxide, calcium hydroxide, organic amines, and sodium carbonate, all as a catalyst solution dissolved in water.

The resole is typically coated as a solution with water and/or an organic solvent (e.g., an alcohol). Typically, the solution comprises solids from about 70 wt% to about 85 wt%, although other concentrations may be used. If the solids content is very low, more energy is required to remove the water and/or solvent. If the solids content is very high, the viscosity of the resulting phenolic resin is too high, which often leads to processing problems.

Phenolic resins are well known and readily available from commercial sources. Examples of commercially available resoles that may be used in the practice of the present disclosure include those sold under the tradename VARCUM (e.g., 29217, 29306, 29318, 29338, 29353) by Durez Corporation (Durez Corporation); those sold under the trade name aerofen (e.g., aerofen 295) by Ashland Chemical company of barton, Florida, usa; and those sold under the trade name PHENOLITE (e.g., PHENOLITE TD-2207) by South of the river Chemical limited, Seoul, South Korea.

The binder precursor may also contain optional additives such as, for example, fillers (including grinding aids), fibers, lubricants, wetting agents, surfactants, pigments, dyes, coupling agents, resin curing agents, plasticizers, antistatic agents, and suspending agents. Examples of fillers suitable for use in the present invention include: wood pulp, vermiculite, and combinations thereof; metal carbonates such as calcium carbonate (e.g., chalk, calcite, marl, travertine, marble and limestone), calcium magnesium carbonate, sodium carbonate and magnesium carbonate; silica such as amorphous silica, quartz, glass beads, glass bubbles, and glass fibers; silicates such as talc, clay (montmorillonite), feldspar, mica, calcium silicate, calcium metasilicate, sodium aluminosilicate, sodium silicate; metal sulfates such as calcium sulfate, barium sulfate, sodium aluminum sulfate, aluminum sulfate; gypsum; vermiculite; wood flour; aluminum trihydrate; metal oxides such as calcium oxide (lime), aluminum oxide, titanium dioxide, and metal sulfites such as calcium sulfite.

The binder precursor can be applied by any known coating method including, for example, roll coating, extrusion die coating, curtain coating, knife coating, gravure coating, and spray coating.

The basis weight of the make layer used may depend on, for example, the intended use, the type and grade of abrasive particles, and the nature of the coated abrasive disk produced, but will typically be in the range of 1 gram per square meter (gsm), 2gsm, 5gsm, 10gsm, or 15gsm to 20gsm, 25gsm, 100gsm, 200gsm, 300gsm, 400gsm, or even 600 gsm.

Fig. 2A is a method of making a patterned coated abrasive article according to embodiments described herein. The method 200 may be used to provide a patterned coated abrasive article.

Details regarding the general manufacture of coated abrasive articles can be found, for example, in U.S. Pat. Nos. 4,734,104(Broberg), 4,737,163(Larkey), 5,203,884(Buchanan et al), 5,152,917(Pieper et al), 5,378,251(Culler et al), 5,417,726(Stout et al), 5,436,063(Follett et al), 5,496,386(Broberg et al), 5,609,706(Benedict et al), 5,520,711(Helmin), 5,954,844(Law et al), 5,961,674(Gagliardi et al), 4,751,138(Bange et al), 5,766,277(DeVoe et al), 6,077,601(DeVoe et al), 6,228,133(Thurber et al), and 5,975,988 (Christianson).

As noted above, it may be helpful to have the abrasive article with abrasive particles applied in a pattern. It is contemplated that in some embodiments, it may be more efficient to apply some layers uniformly in the coated abrasive article, and only a subset of the layers have the desired pattern. It may also be helpful to apply a pattern in all or almost all layers. However, applying a pattern in a subset of layers may provide a functional difference in abrading efficiency, or this may be used to associate the abrasive article with a particular manufacturer or to detect counterfeit products from different manufacturers. In addition, the patterned coating may require special tools. Thus, reducing the number of coatings that need to be patterned can reduce manufacturing costs. However, when only a subset of the coating was patterned, improvement in the patterned coating was still seen. For example, a patterned primer coating with a full size coating helps resist sand shedding.

In block 210, a backing is provided. Exemplary suitable materials for the backing include polymeric films, metal foils, woven fabrics, knitted fabrics, paper, vulcanized fiber, nonwoven fabrics, foams, wire meshes, nets, laminates, combinations thereof and treated versions thereof. Optionally, the coated abrasive article may further include, for example, a backsize (i.e., a coating on the major surface of the backing opposite the major surface having the abrasive coating), a presize or tie layer (i.e., a coating between the abrasive coating and the major surface to which the abrasive coating is secured), and/or an impregnant covering both major surfaces of the backing. The backing may also have a laminate applied as described in, for example, co-owned pending U.S. provisional applications 62/945242 and 62/945244, both of which were filed on 12/9 of 2019.

In block 220, a primer coating is provided. The primer coating may be applied as a curable primer layer deposited on a major surface of the backing. Application of the primer coating can be accomplished by any suitable method including, for example, spray coating, curtain coating, slot coating, roll coating, and/or knife coating. The coating weight will depend on the application and will be apparent to those skilled in the art. In one embodiment, the primer coating precursor is applied in a pattern on the backing, as indicated by block 222. For example, the primer coating precursor can be sprayed through a mask such that the primer coating precursor contacts and covers the backing substrate in a desired pattern. However, in other embodiments, the primer coating precursor is applied as a uniform coating, as indicated in block 224, such that the entire backing substrate receives a substantially uniform coating of the primer coating precursor. In some embodiments, other methods are possible, including gravure coating, flexographic printing, patterned roll coating, screen printing, or stencil printing.

In block 230, abrasive particles are provided. As discussed herein, the abrasive particles can include crushed abrasive particles, plate abrasive particles, and/or shaped abrasive particles. In some embodiments, applying abrasive particles may include providing abrasive particles of a first size and a second size. In some embodiments, providing abrasive particles can further include providing a plurality of types of abrasive particles, such as shaped abrasive particles and crushed abrasive particles.

In some preferred embodiments, at least some of the abrasive particles may be deposited according to a predetermined pattern. Examples of patterns include rectangular grids, parallel bars, hexagonal grids, parallel wavy lines, checkerboards, spirals, and arrays of partially filled circles. Some example patterns are shown in U.S. provisional application 62/945242 filed on 9.12.2019.

In embodiments where the patterned make coat precursor is applied in block 220, it may not be necessary to deposit the abrasive particles in a pattern because particles that land on areas of the backing without the make coat precursor will not adhere to the backing. Thus, the abrasive can be uniformly applied over the make coat precursor, as indicated in block 234.

However, it is also expressly contemplated that whether the make coat is applied uniformly or in a pattern, it may be beneficial to apply the abrasive particles in a pattern, as indicated by block 232. For example, the particles may be applied more densely in different areas of the abrasive article. In addition, different sized particles can be applied in different patterns. Further, the shaped abrasive particles can be applied to the same article in a different pattern than the crushed abrasive particles. As used herein, the term "pattern" refers to the overall pattern formed by the abrasive particles, rather than to the individual abrasive particles that make up the pattern.

After or during deposition of the abrasive particles, the curable make layer precursor is sufficiently cured (e.g., using heat and/or electromagnetic radiation) such that the make layer and abrasive particles are secured to the backing.

In block 240, a size coat is applied. In some embodiments, applying the size coat may include applying a size coat precursor that is later cured to produce the size coat. A size layer may be applied over the fully or at least partially cured primer layer. Coating may be accomplished by any suitable method, including, for example, spray coating, curtain coating, slot coating, roll coating, and/or knife coating. The coating weight will depend on the application and will be apparent to those skilled in the art. The curable size layer precursor is cured, for example, using heat and/or electromagnetic radiation. In one embodiment, the size coat is applied in a pattern, as indicated by block 242. The size coat may be applied as a pattern, regardless of whether the make coat or abrasive particles are pattern coated. For example, the size coat can be applied in a pattern to indicate the manufacturer or grade of the abrasive article. Additionally, as indicated by block 244, the size coat may be applied as a uniform coating over the patterned coated layer of abrasive particles and/or the patterned coated make coat. Because of the relative size of the abrasive particles compared to the abrasive article, the uniformly applied size coat can at least partially obscure the patterning of the abrasive particles, thereby producing an abrasive article that appears similar to a non-patterned coated abrasive article.

In block 250, additional functional layers may be provided. The functional layer may be applied as a supplement to the supersize coat or as a supersize coat. The functional layer can be deposited in a pattern, as indicated at block 252, which may be the same as or different from any patterned layer of abrasive particles. Additionally, in some embodiments, the functional layer is applied as a uniform coating, as indicated by block 254. For example, it may be desirable to, for example, deposit the grinding aid uniformly on the article. Additionally, the functional layer may also include a grinding aid and/or an antiloading material. For example, the supersize coat may be applied in a pattern to indicate the manufacturer or grade of the abrasive article.

Grinding aids are defined as particulate materials that are added to abrasive articles to have a significant impact on the chemical and physical processes of abrading. In particular, it is believed that the grinding aid may: (1) reducing friction between the abrasive particles and the workpiece being abraded; (2) prevent the abrasive particles from "plugging", i.e., preventing the metal particles from being welded to the top of the abrasive particles; (3) reducing the temperature of the interface between the abrasive particles and the workpiece; (4) the grinding force is reduced; and/or (5) synergistic effects with the above mechanisms. Generally, the addition of a grinding aid can increase the useful life of the coated abrasive article. Grinding aids encompass a wide variety of different materials and can be inorganic or organic.

Exemplary grinding aids can include inorganic halide salts, halogenated compounds and polymers, and organic and inorganic sulfur-containing materials. Exemplary grinding aids can be organic or inorganic and include waxes, halogenated organic compounds, e.g., chlorinated waxes such as naphthalene tetrachloride, naphthalene pentachloride, and polyvinyl chloride; halide salts such as sodium chloride, potassium cryolite, sodium cryolite, ammonium cryolite, potassium tetrafluoroborate, sodium tetrafluoroborate, silicon fluorides, potassium chloride, magnesium chloride; and metals and their alloys, such as tin, lead, bismuth, cobalt, antimony, cadmium, iron, and titanium. Examples of other grinding aids include sulfur, organic sulfur compounds, graphite and metal sulfides, organic and inorganic phosphate containing materials. Combinations of different grinding aids can be used.

Preferred grinding aids include halide salts, particularlyWhich is potassium tetrafluoroborate (KBF) ₄ ) Cryolite (Na) ₃ AlF ₆ ) And ammonium cryolite [ (NH) ₄ ) ₃ AlF ₆ ]. Other halide salts that may be used as grinding aids include sodium chloride, elpasolite, sodium tetrafluoroborate, silicon fluoride, potassium chloride, and magnesium chloride. Other preferred grinding aids are those in U.S. patent 5,269,821(Helmin et al), which describes grinding aid agglomerates composed of water soluble and water insoluble grinding aid particles. Other useful grinding aid agglomerates are those in which a plurality of grinding aid particles are bound together with a binder to form an agglomerate. Agglomerates of this type are described in U.S. Pat. No. 5,498,268(Gagliardi et al).

Examples of halogenated polymers that can be used as grinding aids include: polyvinyl halides (e.g., polyvinyl chloride) and polyvinylidene halides, such as those disclosed in U.S. patent 3,616,580(Dewell et al); highly chlorinated paraffins such as those disclosed in U.S. patent 3,676,092 (Buell); fully chlorinated hydrocarbon resins such as those disclosed in U.S. patent 3,784,365 (casterta et al); and fluorocarbons such as polytetrafluoroethylene and polychlorotrifluoroethylene as disclosed in U.S. patent 3,869,834(Mullin et al).

Inorganic sulfur-containing materials useful as grinding aids include elemental sulfur, ferrous sulfide, copper sulfide, molybdenum sulfide, potassium sulfate, and the like, as disclosed variously in U.S. Pat. Nos. 3,833,346(Wirth), 3,868,232(Sioui et al), and 4,475,926 (Hickory). Organic sulfur-containing materials (e.g., thiourea) useful in the present invention include those mentioned in U.S. patent 3,058,819 (Paulson).

The present disclosure also contemplates the use of a combination of different grinding aids, and in certain instances, this can produce a synergistic effect. The above-mentioned examples of grinding aids are intended as a representative description of grinding aids, and they are not intended to encompass all grinding aids.

The coated abrasive article can also include grinding aid particles arranged randomly, in a single predetermined pattern, or in a plurality of different patterns. At least a portion of the grinding aid particles can be positioned such that the pattern formed by the grinding aid particles comprises a plurality of parallel lines and/or a grid pattern. As another example, at least a portion of the grinding aid particles can be positioned such that the pattern formed by these grinding aid particles comprises a plurality of circles (hollow or filled). Also, at least a portion of the grinding aid particles can be arranged in a spiral, checkerboard, or stripe (in any orientation). The pattern of grinding aid particles can be the same as or different from the pattern of abrasive particles. The grinding aid particles (whether non-patterned) can be deposited as part of the deposition of abrasive particles discussed above with respect to step 230 or as part of a supersize coat applied as part of the functional coating described in block 250.

FIG. 2B is a flow chart 260 showing the result of including patterns in different applied layers on the backing. The flow chart 260 assumes that a single pattern is applied at any of the layers, and that for multiple layers, the same pattern is applied. However, it is expressly contemplated that the pattern of abrasive particles may be different than, for example, a patterned size coat. In addition, FIG. 2B only shows the abrasive article 270 resulting from the application of a patterned or uniformly coated make 262, abrasive particle layer 264, or size layer 266. However, it is expressly contemplated that a supersize layer or additional functional layer, which may be treated similarly to size layer 266, is also contemplated.

FIG. 3 is a diagrammatic view of a method of making a patterned coated abrasive article according to embodiments described herein. Fig. 3 shows a diagram 300 illustrating the deposition of different layers on a backing 320. Each layer is deposited by one of several dispensers 310. However, while several dispensers 310 are discussed, it is contemplated that in some embodiments, one dispenser 310 may dispense multiple layers of material.

The abrasive article has a backing 320 that may undergo one or more pretreatments or receive one or more make layers. The primer layer and pretreatment may alter the characteristics of the backing 320, for example, changing the hardness of the backing 320 to be greater or less than it would be without the pretreatment or primer layer.

The first dispenser 310 dispenses a primer coating 330 or a primer coating precursor that can be cured to the primer coating 330 onto the backing 320. Primer coating 330 may be deposited directly onto backing 320 or may be deposited onto a laminate deposited directly onto backing 320, as described in, for example, U.S. provisional applications 62/945242 and 62/945244, both filed on 12/9/2019. In one embodiment, the primer coating 330 or primer coating precursor can be deposited on the backing 320 as a uniform coating or as a uniform layer on the surface of the backing 320. In another embodiment, the primer coating 330 or primer coating precursor can be deposited in a pattern such that portions of the backing 320 do not receive the primer coating 330 or primer coating precursor.

The second dispenser 310 dispenses abrasive particles 340. Abrasive particles 340 may be shaped abrasive particles, crushed abrasive particles, and/or plate-like abrasive particles. Dispensing abrasive particles 340 from the second dispenser 310 may include dispensing a first set of abrasive particles 340 and a second set of abrasive particles 340.

The abrasive particles 340 may be dispensed by the dispenser 310 in a pattern such that some areas of the applied make coat 330 or some areas of the applied backing 320 remain uncovered. It is expressly contemplated that abrasive particles 340 can be deposited in a pattern, regardless of whether make coat 330 is deposited in a pattern, as shown in fig. 2B. However, if the make coat 330 is applied in a pattern and the abrasive particles 340 are uniformly applied, only the abrasive particles 340 embedded within the pattern of the make coat 330 will adhere to and be incorporated into the final abrasive article.

It is also contemplated that, while only one type and size of abrasive particles 340 is shown in fig. 3, in some embodiments, a first set of abrasive particles and a second set of abrasive particles are deposited. For example, the first and second sets of abrasive particles may differ in type, selected from shaped abrasive particles, crushed abrasive particles, plate-like abrasive particles, or agglomerate abrasive particles. Additionally or alternatively, the first and second sets of abrasive particles can differ in size, composition, or deposition pattern.

A size coat 350 or size coat precursor is deposited on top of the abrasive particles 340. Many size coatings impart color to abrasive particles, either naturally or by including pigments. Thus, pattern coating the size coating 350 can produce a visual pattern that is visibly apparent to a user of the abrasive article. While capable of detecting the pattern of abrasive particles 340, in some embodiments, abrasive particles 340 are small enough that the pattern is not readily visible. Because the pattern of abrasive particles 340 may change the quality or behavior of the abrasive article, the patterned size coating may help indicate to a user one or more attributes on the abrasive article, such as the grade or size of the abrasive particles.

One or more topcoat layers 360 may be applied over the size coat 350. The supersize coat may impart additional functionality to the abrasive article, such as grinding aids, lubricants, or other particles. The supersize coat 360 may also impart a color or visual indication to the final abrasive article.

Fig. 4A-4D illustrate a patterned coated abrasive article according to embodiments described herein. 4A and 4B show a patterned coated abrasive disk coated with a supersize layer. FIG. 4C shows a reticulated abrasive with a uniformly applied size coat. FIG. 4D shows a web-shaped abrasive having a size coat with a patterned coating.

The abrasive particles used in the embodiments herein, whether crushed or shaped, should have sufficient hardness and surface roughness to be useful as abrasive particles in abrading processes. Preferably, the abrasive particles have a mohs hardness of at least 4, at least 5, at least 6, at least 7, or even at least 8.

Useful ABRASIVE materials include, for example, fused aluminum oxide, heat treated aluminum oxide, white fused aluminum oxide, CERAMIC aluminum oxide materials (such as those commercially available as 3M CERAMIC ABRASIVE GRAIN from 3M Company of saint paul, Minnesota), black silicon carbide, green silicon carbide, titanium diboride, boron carbide, tungsten carbide, titanium carbide, cubic boron nitride, garnet, fused alumina zirconia, sol gel derived CERAMICs (e.g., alumina CERAMICs doped with chromia, ceria, zirconia, titania, silica, and/or tin oxide), silica (e.g., quartz, glass beads, glass bubbles, and glass fibers), feldspar, or steatite. Examples of sol gel derived crushed ceramic particles can be found in U.S. Pat. Nos. 4,314,827(Leitheiser et al), 4,623,364(Cottringer et al), 4,744,802(Schwabel), 4,770,671(Monroe et al), and 4,881,951(Monroe et al).

As previously mentioned, the abrasive particles can be shaped (e.g., precisely shaped) or random (e.g., crushed). Shaped abrasive particles and precisely shaped abrasive particles can be prepared, for example, by a molding process using sol-gel techniques described in the following patents: U.S. Pat. Nos. 5,201,916(Berg), 5,366,523(Rowenhorst (Re 35,570)) and 5,984,988 (Berg). U.S. patent 8,034,137(Erickson et al) describes alumina particles that have been formed into a particular shape and then crushed to form fragments that retain a portion of their original shape characteristics. Exemplary shapes of abrasive particles include crushed, pyramidal (e.g., 3-face, 4-face, 5-face, or 6-face pyramidal), truncated pyramidal (e.g., 3-face, 4-face, 5-face, or 6-face truncated pyramidal), cones, truncated cones, rods (e.g., cylindrical, worm-like), and prisms (e.g., 3-face, 4-face, 5-face, or 6-face prisms).

The abrasive particles can be independently sized according to a specified nominal grade recognized by the abrasives industry. Exemplary abrasive industry recognized grading standards include those promulgated by ANSI (american national standards institute), FEPA (european union of manufacturers of abrasives), and JIS (japanese industrial standard). ANSI grade designations (i.e., specified nominal grades) include, for example: ANSI 4, ANSI6, ANSI 8, ANSI 16, ANSI 24, ANSI 36, ANSI 46, ANSI 54, ANSI60, ANSI 70, ANSI 80, ANSI 90, ANSI 100, ANSI 120, ANSI 150, ANSI 180, ANSI220, ANSI 240, ANSI 280, ANSI 320, ANSI 360, ANSI 400, and ANSI 600. FEPA grade designations include F4, F5, F6, F7, F8, F10, F12, F14, F16, F20, F22, F24, F30, F36, F40, F46, F54, F60, F70, F80, F90, F100, F120, F150, F180, F220, F230, F240, F280, F320, F360, F400, F500, F600, F800, F1000, F1200, F1500, F2000, P12, P16, P20, P24, P30, P36, P40, P50, P60, P80, P100, P120, P150, P180, P220, P240, P280, P320, P360, P400, P500, P600, P1000, P2500, P1000, P1200, and P1200. JIS grade designations include: JIS8, JIS12, JIS16, JIS24, JIS36, JIS46, JIS54, JIS60, JIS80, JIS100, JIS150, JIS180, JIS220, JIS240, JIS280, JIS320, JIS360, JIS400, JIS600, JIS800, JIS1000, JIS1500, JIS2500, JIS4000, JIS6000, JIS8000 and JIS10,000.

Examples of shaped abrasive particles can be found in U.S. Pat. Nos. 5,201,916(Berg), 5,366,523(Rowenhorst (Re 35,570)), and 5,984,988 (Berg). U.S. patent 8,034,137(Erickson et al) describes crushed abrasive particles of alumina that have been formed into a particular shape and then crushed to form chips that retain a portion of their original shape characteristics. In some embodiments, the shaped alpha alumina particles are precisely-shaped particles (i.e., the particles have a shape determined, at least in part, by the shape of the cavities in the production tool used to make them). Details on such precisely shaped abrasive particles and methods of making them can be found, for example, in U.S. Pat. Nos. 8,142,531(Adefris et al), 8,142,891(Culler et al), and 8,142,532(Erickson et al); and U.S. patent application publications 2012/0227333 (adegris et al), 2013/0040537(Schwabel et al), and 2013/0125477 (adegris).

In those embodiments where the abrasive particles are shaped as triangular pieces (or triangular truncated pyramids), they may have a major surface with an apex at 90 degrees (corresponding to a right triangle), or they may have a major surface with an apex greater than 90 degrees (corresponding to an obtuse triangle), although this is not required. Examples include at least 91 degrees, at least 95 degrees, at least 100 degrees, at least 110 degrees, at least 120 degrees, or even at least 130 degrees.

In some preferred embodiments, the abrasive particles comprise plate-like crushed abrasive particles. Such abrasive particles may be obtained from commercial suppliers by known methods, and/or by shape sorting such crushed abrasive particles; for example, using shape sorting tables known in the art.

Examples of suitable abrasive particles include crushed abrasive particles comprising: fused aluminum oxide, heat treated aluminum oxide, white fused aluminum oxide, ceramic aluminum oxide materials (such as those commercially available as 3M ceramic ABRASIVE GRAIN from 3M company of St. Paul, Minn.), brown aluminum oxide, blue aluminum oxide, silicon carbide (including green silicon carbide), titanium diboride, boron carbide, tungsten carbide, garnet, titanium carbide, diamond, cubic boron nitride, fused zirconia corundum, iron oxide, chromium oxide, zirconium oxide, titanium dioxide, quartz, feldspar, flint, emery, sol-gel process ceramics (e.g., alpha alumina), and combinations thereof. Additional examples include crushed abrasive composites of abrasive particles (which may or may not be plate-like) in a binder matrix, such as those described in U.S. Pat. No. 5,152,917(Pieper et al). Many such abrasive particles, agglomerates, and composites are known in the art.

Preferably, the crushed abrasive particles comprise ceramic crushed abrasive particles, such as, for example, sol-gel derived polycrystalline alpha alumina particles. Ceramic crushed abrasive particles comprised of crystallites of alpha alumina, magnesium aluminate spinel and rare earth hexaaluminate can be prepared using sol-gel alpha alumina particle precursors according to the methods described in, for example, U.S. patent 5,213,591(Celikkaya et al) and U.S. published patent applications 2009/0165394 a1(Culler et al) and 2009/0169816 a1(Erickson et al).

Examples of sol-gel process-prepared abrasive particles from which the crushed abrasive particles can be isolated and methods for making the same can be found in U.S. Pat. Nos. 4,314,827(Leitheiser et al), 4,623,364(Cottringer et al), 4,744,802(Schwabel), 4,770,671(Monroe et al), and 4,881,951(Monroe et al). It is also contemplated that the crushed abrasive particles may comprise abrasive agglomerates such as, for example, those described in U.S. Pat. No. 4,652,275(Bloecher et al) or U.S. Pat. No. 4,799,939(Bloecher et al). In some embodiments, the crushed abrasive particles may be surface treated with a coupling agent (e.g., an organosilane coupling agent) or other physical treatment (e.g., iron oxide or titanium oxide) to enhance adhesion of the crushed abrasive particles to the binder. The crushed abrasive particles may be treated prior to their combination with the binder, or they may be surface treated in situ by including a coupling agent to the binder.

Additional details regarding the process of making sol-gel derived abrasive particles can be found, for example, in U.S. Pat. Nos. 4,314,827(Leitheiser), 5,152,917(Pieper et Al), 5,435,816(Spurgeon et Al), 5,672,097(Hoopman et Al) 5,946,991(Hoopman et Al) 5,975,987(Hoopman et Al) and 6,129,540(Hoopman et Al), and U.S. published patent application 2009/0165394 Al (Culler et Al).

Surface coatings on various abrasive particles can be used to improve adhesion between the abrasive particles and the binder in the abrasive article, or can be used to aid in electrostatic deposition. In one embodiment, the surface coating described in U.S. Pat. No. 5,352,254(Celikkaya) may be used in an amount of 0.1% to 2% of the surface coating relative to the weight of the abrasive particles. Such surface coatings are described in U.S. Pat. Nos. 5,213,591(Celikkaya et al), 5,011,508(Wald et al), 1,910,444(Nicholson), 3,041,156(Rowse et al), 5,009,675(Kunz et al), 5,085,671(Martin et al), 4,997,461(Markhoff-Matheny et al) and 5,042,991(Kunz et al). Additionally, the surface coating may prevent plugging of the shaped abrasive particles. The term "capping" is used to describe the phenomenon of metal particles from the workpiece being abraded welding on top of the crushed abrasive particles. Surface coatings that perform the above functions are known to those skilled in the art.

The crushed abrasive particles used in the practice of the present disclosure are preferably selected to have a length and/or width in the range of 0.1 to 3500 microns, more typically in the range of 100 to 3000 microns, and more typically in the range of 100 to 2600 microns, although other lengths and widths may also be used.

The crushed abrasive particles may be selected to have a thickness in the range of 0.1 to 1600 micrometers, more typically 1 to 1200 micrometers, although other thicknesses may be used. In some embodiments, the plate-like crushed abrasive particles may have an aspect ratio (length to thickness) of at least 2, 3, 4, 5,6, or more.

The length, width and thickness of the abrasive particles may be determined on an individual or average basis as desired. Suitable techniques may include inspection and measurement of individual particles, as well as the use of automated image analysis techniques (e.g., the use of a dynamic image analyzer, such as the camsize XT image analyzer available from Retsch Technology Gmbh, Haan, Germany, leich technologies Gmbh) according to test method ISO 13402-2:2006 "particle size analysis-image analysis method-part 2: dynamic graph analysis method ".

Fig. 5 illustrates a method of using a patterned coated abrasive article according to embodiments described herein. Fig. 5 may be referred to in connection with the abrasive article 600 of fig. 6. As shown in fig. 6, at least some of the shaped abrasive particles have an asymmetric profile when viewed from the side. This results in each abrasive particle 630 having a cutting face. In some embodiments, the shaped abrasive particles are oriented such that the cutting faces of at least some of the abrasive particles 630 are aligned and such that the cutting tips are oriented away from the backing, as described in 62/924,956 filed, for example, on day 10, 23, 2019. Abrasive particles 630 may be embedded within make coat 620 such that particles 630 are aligned perpendicular to backing 610, or such that an angle of inclination 660 exists. Size coat 640 may also be present.

The method 500 may be used to grind a plurality of different workpieces. Upon contact, one of the abrasive article and the workpiece are moved relative to each other in the use direction, and a portion of the workpiece is removed.

Examples of workpiece materials include metals, metal alloys, steel, alloy steels, aluminum-dissimilar metal alloys, ceramics, glass, wood-like materials, composites, painted surfaces, plastics, reinforced plastics, stone, and/or combinations thereof. The workpiece may be flat or have a shape or profile associated therewith. Exemplary workpieces include metal parts, plastic parts, particle boards, camshafts, crankshafts, furniture, and turbine blades.

Abrasive articles according to the present invention may be used to abrade a workpiece. The methods of abrading range from snagging (i.e., high pressure high cut) to abrading (e.g., abrading medical implants with abrasive tapes), the latter of which are typically made with finer grit sizes. One such method comprises the steps of: an abrasive article (e.g., a coated abrasive article, a nonwoven abrasive article, or a bonded abrasive article) is brought into frictional contact with a surface of a workpiece, and at least one of the abrasive article or the workpiece is moved relative to the other to abrade at least a portion of the surface.

In block 510, an abrasive article is provided. In one embodiment, an abrasive article includes a plurality of abrasive particles configured to have a first direction of use and a second direction of use. For example, referring to FIG. 6, moving the abrasive article in a first use direction refers to moving the abrasive article in direction 650 such that the cutting face 630 first encounters the workpiece. The second use direction refers to moving the abrasive article in direction 660. According to various embodiments, a method of using an abrasive article, such as an abrasive tape or disc, includes contacting shaped abrasive particles with a workpiece or substrate.

According to various embodiments, the depth of cut in the substrate or workpiece may be at least about 10 μm, at least about 20 μm, at least about 30 μm, at least about 40 μm, at least about 50 μm, or at least about 60 μm. A portion of the substrate or workpiece is removed as swarf by the abrasive article.

In block 520, the abrasive article is moved against the workpiece in a first direction, indicated, for example, as direction 650 in fig. 6.

According to various embodiments, the abrasive articles described herein may have several advantages when moved in a preferred direction of use. For example, the amount of material removed from the workpiece, the depth of cut in the workpiece, the surface roughness of the workpiece, or a combination thereof is greater in a first direction than in any other second direction at the same applied force, cutting speed, or a combination thereof.

For example, at least about 10%, or at least about 15%, at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at least about 65%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 100%, at least about 120%, at least about 130%, at least about 140%, at least about 150% more material is removed from the substrate or workpiece in the first use direction. In some embodiments, about 15% to about 500%, or about 30% to about 70%, or about 40% to about 60%, or less than, equal to, or greater than about 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 100%, 105%, 110%, 115%, 120%, 125%, 130%, 135%, 140%, 145%, 150%, 155%, 160%, 165%, 170%, 175%, 180%, 185%, 190%, 195%, 200%, 205%, 210%, 215%, 220%, 225%, 230%, 235%, 240%, 245%, 250%, 255%, 260%, 265%, 270%, 275%, 285%, 290%, 295%, 300%, 310%, 315%, 320%, 325%, 330%, 335%, 305%, 345%, in the first direction of use is removed in excess, 350%, 355%, 360%, 365%, 370%, 375%, 380%, 385%, 390%, 395%, 400%, 405%, 410%, 415%, 420%, 425%, 430%, 435%, 440%, 445%, 450%, 455%, 460%, 465%, 470%, 475%, 480%, 485%, 490%, 495%, or about 500% material. The amount of material removed may be referenced to an initial cut (e.g., the first cut of a cutting cycle) or a total cut (e.g., the sum of the amounts of material removed over a set number of cutting cycles).

As another example, the depth of cut in the substrate or workpiece may be at least about 10%, or at least about 30%, at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at least about 65%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 100%, at least about 120%, at least about 130%, at least about 140%, at least about 150% deeper in the first use direction. In some embodiments, the depth in the first use direction is from about 10% to about 500%, or from about 30% to about 70%, or from about 40% to about 60%, or less than, equal to, or greater than about 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 100%, 105%, 110%, 115%, 120%, 125%, 130%, 135%, 140%, 145%, 150%, 155%, 160%, 165%, 170%, 175%, 180%, 185%, 190%, 195%, 200%, 205%, 210%, 215%, 220%, 225%, 230%, 235%, 240%, 245%, 250%, 255%, 260%, 265%, 270%, 275%, 280%, 285%, 290%, 295%, 300%, 310%, 315%, 320%, 325%, 330%, 335%, 340%, 345%, 350%, (ii., 355%, 360%, 365%, 370%, 375%, 380%, 385%, 390%, 395%, 400%, 405%, 410%, 415%, 420%, 425%, 430%, 435%, 440%, 445%, 450%, 455%, 460%, 465%, 470%, 475%, 480%, 485%, 490%, 495%, or about 500%.

As another example, the arithmetic mean roughness value (Sa) of a workpiece or substrate cut by moving the abrasive article in a first direction of use may be higher than a corresponding substrate or workpiece cut under identical conditions but in a second direction of movement. For example, when cutting a workpiece or substrate in a first direction, the surface roughness may be about 30% higher, or about 40% higher, about 50% higher, about 60% higher, about 70% higher, about 80% higher, about 90% higher, about 100% higher, about 110% higher, about 120% higher, about 130% higher, about 140% higher, about 150% higher, about 160% higher, about 170% higher, about 180% higher, about 190% higher, about 200% higher, about 210% higher, about 220% higher, about 230% higher, about 240% higher, about 250% higher, about 260% higher, about 270% higher, about 280% higher, about 290% higher, about 300% higher, about 310% higher, about 320% higher, about 330% higher, about 340% higher, about 350% higher, about 360% higher, about 370% higher, about 380% higher, about 390% higher, about 400% higher, about 410% higher, about 420% higher, about 430% higher, about 440% higher, about 450% higher, about 460% higher, about 470% higher, about 480% higher, about 490% higher, or about 500% higher. The arithmetic mean roughness value may be in a range of about 1000 to about 2000, about 1000 to about 1100, or less than, equal to, or greater than about 1000, 1050, 1100, 1150, 1200, 1250, 1300, 1350, 1400, 1450, 1500, 1550, 1600, 1650, 1700, 1750, 1800, 1850, 1900, 1950, or about 2000.

Alternatively, as shown at block 530, the abrasive article can be moved in a second direction 660 different from the use direction 650. Although fig. 6 illustrates the second direction 660 as being 180 degrees different from the first direction 650, the second direction 660 may be rotated about 1 degree to 360 degrees, about 160 degrees to about 200 degrees, less than, equal to, or greater than about 1 degree, 5 degrees, 10 degrees, 15 degrees, 20 degrees, 25 degrees, 30 degrees, 35 degrees, 40 degrees, 45 degrees, 50 degrees, 55 degrees, 60 degrees, 65 degrees, 70 degrees, 75 degrees, 80 degrees, 85 degrees, 90 degrees, 95 degrees, 100 degrees, 105 degrees, 110 degrees, 115 degrees, 120 degrees, 125 degrees, 130 degrees, 135 degrees, 140 degrees, 145 degrees, 150 degrees, 155 degrees, 160 degrees, 165 degrees, 170 degrees, 175 degrees, 180 degrees, 185 degrees, 190 degrees, 195 degrees, 200 degrees, 205 degrees, 210 degrees, 215 degrees, 335 degrees, 220 degrees, 230 degrees, 240 degrees, 250 degrees, 260 degrees, 265 degrees, 270 degrees, 280 degrees, 275 degrees, 190 degrees, 295 degrees, 305 degrees, 315 degrees, 325 degrees, 310 degrees, 300 degrees, 325 degrees, 300 degrees, 325 degrees, 300 degrees, 15 degrees, 60 degrees, 15 degrees, 130 degrees, 60, 340 degrees, 350 degrees, 355 degrees, or about 360 degrees.

While it may be desirable to move the abrasive article in the first use direction 650, there are some reasons to move the abrasive article in the second direction 660. For example, contacting the substrate or workpiece with the abrasive article and moving the abrasive article in the second direction 660 can be beneficial for polishing the substrate or workpiece. While not intending to be bound by any particular theory, the inventors hypothesize that movement in the second direction may expose the substrate or workpiece to an angle other than the angle of inclination of the abrasive article, which is more suitable for polishing applications.

Coated abrasive articles made according to the methods of the present disclosure may be used, for example, to abrade a workpiece. Examples of workpiece materials include metals, metal alloys, dissimilar metal alloys, ceramics, glass, wood-like materials, composites, painted surfaces, plastics, reinforced plastics, stone, and/or combinations thereof. The workpiece may be flat or have a shape or profile associated therewith. Exemplary workpieces include metal parts, plastic parts, particle board, camshafts, crankshafts, furniture, and turbine blades. The force applied during grinding is typically in the range of about 1 kg to about 100 kg.

Coated abrasive articles made according to the methods of the present disclosure may be used manually and/or in conjunction with a machine. While abrading, at least one of the coated abrasive article and the workpiece is moved relative to the other. The milling may be performed under wet or dry conditions. Exemplary liquids for wet milling include water, water containing conventional rust inhibiting compounds, lubricants, oils, soaps, and cutting fluids. The liquid may also contain, for example, antifoam agents, degreasers.

All cited references, patents, and patent applications incorporated by reference in this application are incorporated by reference in a consistent manner. In the event of inconsistencies or contradictions between the incorporated reference parts and the present application, the information in the present application shall prevail. The preceding description, given to enable one of ordinary skill in the art to practice the claimed disclosure, is not to be construed as limiting the scope of the disclosure, which is defined by the claims and all equivalents thereto.

A coated abrasive article is provided. The coated abrasive article includes a backing having opposed first and second major surfaces. The coated abrasive article includes a make coat bonded to the first major surface. The coated abrasive article also includes abrasive particles that are directly bonded to the make coat. The abrasive particles are at least partially embedded in the make coat. The coated abrasive article also includes a size layer directly bonded to the make layer and the abrasive particles. One of the make coat and the size coat includes a patterned coating.

The article may be implemented such that the patterned coating comprises any of lines, swirls, polygons, letters, or numbers.

The article can be implemented such that the make layer comprises a patterned coating, and wherein the size layer comprises a uniform coating, such that for a portion of the backing, the size layer directly contacts the backing.

The article can be implemented such that both the make layer and the size layer include a patterned coating.

The article may be implemented such that the size layer includes a patterned coating, and wherein the coated abrasive article includes a first color and a second color, and wherein the first color is the color of the size layer.

The article may also include a topcoat.

The article can be implemented such that the supersize coating includes a supersize pattern.

The article can be implemented such that the make layer includes a cured resin.

The article may be implemented such that the size layer includes a cured resin.

The article may be implemented such that the backing comprises a polymeric film, a metal foil, a woven fabric, a knitted fabric, paper, vulcanized fiber, a nonwoven, a foam, a screen, a mesh, or a combination thereof.

The article can be implemented such that it further comprises a laminate coated directly to the first major surface of the backing, and wherein the make layer is bonded to the laminate.

The article may be implemented such that the backing is pre-treated with a backsize, presize, or impregnant.

The article can be implemented such that the abrasive particles are shaped abrasive particles.

The article can be implemented such that at least some of the shaped abrasive particles are aligned with respect to one another.

The article can be implemented such that at least some of the shaped abrasive particles are aligned, such that the cutting face of each of the shaped abrasive particles is aligned and such that the base of each of the shaped abrasive particles is embedded within the make layer.

The article may be implemented such that the abrasive particles are magnetically coated.

The article can be implemented such that the patterned coating includes repeating units.

The article can be implemented such that the patterned coating extends from the center of the abrasive article to the edge of the abrasive article.

The article may be implemented such that the abrasive article is an abrasive disc or an abrasive tape.

A method of making a coated abrasive article. The method includes depositing a curable make layer precursor on a major surface of the backing. The method also includes depositing a plurality of abrasive particles onto the curable make layer precursor. The method also includes at least partially curing the curable make layer precursor. The method also includes depositing a curable size coat precursor on the plurality of abrasive particles. The method also includes at least partially curing the curable size layer precursor. One of a curable make layer precursor and a curable size layer is deposited in a pattern on a major surface of the backing.

The method may be implemented such that the pattern includes repeating units.

The method may be implemented such that the pattern comprises lines, swirls, polygons, letters, or numbers.

The method may be implemented such that the pattern comprises a first color and a second color.

The method may be implemented such that the first color is a color of the cured size layer.

The method may be implemented such that the method further comprises depositing a top glue layer.

The method may be implemented such that the supersize layer is deposited in a supersize pattern, and wherein the second color comprises a supersize color.

The method can be implemented such that the plurality of abrasive particles are deposited such that only a first portion of each abrasive particle is embedded within the curable make layer precursor and a second portion of each abrasive particle is free of the make layer precursor.

The method can be implemented such that the backing comprises a polymeric film, a metal foil, a woven fabric, a knitted fabric, paper, vulcanized fiber, a nonwoven, a foam, a screen, a mesh, or a combination thereof.

The method can further include depositing a laminate coated directly to the first major surface of the backing, and wherein the make layer is bonded to the laminate.

The method may further comprise pre-treating the backing with a backsize, presize, or impregnant.

The method can be implemented such that the abrasive particles are deposited in a pattern of particles.

The method may be implemented such that the particle pattern is different from the pattern.

The method may be practiced such that the abrasive particles comprise crushed abrasive particles, plate abrasive particles, shaped abrasive particles, or shaped abrasive particles.

The method can be implemented such that the abrasive particles are shaped abrasive particles, and wherein each of the shaped abrasive particles comprises at least one polygonal face.

The method can be implemented such that each of the shaped abrasive particles includes at least one asymmetric surface.

The method can be implemented such that the abrasive particles are magnetically coated.

The method can be implemented such that the abrasive particles are aligned on the backing such that at least one polygonal face of some of the shaped abrasive particles is aligned with respect to one another.

The method can be implemented such that at least one polygonal face of some of the shaped abrasive particles is aligned with respect to the backing.

The method can be implemented such that the abrasive particles are angled relative to the backing.

Examples

All parts, percentages, ratios, and the like in the examples and the remainder of the specification are by weight unless otherwise indicated.

Unless otherwise indicated, all other reagents were obtained or purchased from fine chemical suppliers such as Sigma Aldrich Company of st.

Abbreviations of units used in the examples:

DEG C: degree centigrade

Diameter of

cm: centimeter

in: inch (L)

g: gram (R)

g/m ² : grams per square meter

rpm: revolutions per minute

mm: millimeter

wt.%: by weight%

Process for making a reticulated abrasive

The mesh backing was cut into small disks with a diameter of 6 inches or 3.5 inches before use.

The uniform primer coating was applied by applying 2.36g of primer resin to the diameter using a 3M hand rubber roller

6 inch mesh backing or 1.32g of primer resin applied to the diameter

On a 3.5 inch mesh backing.

The patterned primer coating was achieved by applying a primer resin to the web backing with a 3M hand rubber roller through a patterned stencil as described in U.S. provisional application 62/945242 filed on 2019, 12, 9.

The mineral drop coating is achieved by laying abrasive mineral grits onto the make resin layer.

And (3) curing process: the net-like abrasive sample was pre-cured at 90 ℃ for 2 hours, and then cured at 102 ℃ for at least 6 hours.

FIG. 7A shows the diameter

Is a 3.5 inch mesh backing, and FIG. 7B shows the diameter

A 3.5 inch mesh backing with a patterned primer and mineral coating. FIG. 7C shows the diameter

A 3.5 inch mesh abrasive with a patterned make coat, mineral, and size coat.

FIG. 7D shows the diameter

A 3.5 inch mesh backing with a uniform primer coating and a uniform mineral coating. FIG. 7E shows the diameter

Is a 3.5 inch mesh abrasive with a uniform make coat, a uniform mineral coating, and a patterned size coat. FIG. 7F shows the diameter

A 3.5 inch mesh abrasive with a patterned make coat, a patterned mineral coat, and a uniform size coat.

FIG. 7G shows the diameter

A 3.5 inch backing with BCA and FRPL 220 uniform primer coating and patterned mineral coating. Fig. 7H shows a close-up view of the article of fig. 7G.

FIG. 7I shows the diameter

A 6 inch mesh abrasive article with a uniform make coat, a uniform mineral coating, and a patterned antiloading coating.

The claims (modification according to treaty clause 19)

1. A coated abrasive article comprising:

a backing having opposed first and second major surfaces;

a make coat bonded to the first major surface;

abrasive particles bonded directly to the make coat, wherein the abrasive particles are at least partially embedded in the make coat;

a size layer directly bonded to the make layer and the abrasive particles; and is

Wherein one of the make coat and size coat comprises a patterned coating.

2. The article of claim 1, wherein the patterned coating comprises any of lines, swirls, polygons, letters, or numbers.

3. The article of any one of claims 1 to 2, wherein the make layer comprises the patterned coating, and wherein the size layer comprises a uniform coating such that, for a portion of the backing, the size layer directly contacts the backing.

4. The article of any one of claims 1 to 3, wherein the make layer and the size layer each comprise the patterned coating.

5. The article of any one of claims 1 to 4, wherein the size coat comprises the patterned coating, and wherein the coated abrasive article comprises a first color and a second color, and wherein the first color is the color of the size coat.

6. The article of any one of claims 1 to 5, and further comprising a topcoat.

7. The article of claim 6, wherein the supersize coating comprises a supersize pattern.

8. The article of any one of claims 1 to 7, wherein the primer layer comprises a cured resin.

9. The article of any one of claims 1 to 8, wherein the size layer comprises a cured resin.

10. The abrasive article of any one of claims 1 to 9, wherein the backing comprises a polymeric film, a metal foil, a woven fabric, a knitted fabric, paper, vulcanized fiber, a nonwoven, a foam, a screen, a mesh, or a combination thereof.

11. The abrasive article of any one of claims 1 to 10, and further comprising a laminate coated directly to the first major surface of the backing, and wherein the make layer is bonded to the laminate.

12. The abrasive article of any one of claims 1 to 11, wherein the backing is pre-treated with a backsize, presize, or saturant.

13. The abrasive article of any one of claims 1 to 12, wherein the abrasive particles are shaped abrasive particles.

14. The abrasive article of claim 13, wherein at least some of the shaped abrasive particles are aligned with respect to each other.

15. The abrasive article of claim 14, wherein at least some of the shaped abrasive particles are aligned such that a cutting face of each of the shaped abrasive particles is aligned and such that a base of each of the shaped abrasive particles is embedded within the make coat.

16. The abrasive article of any one of claims 13 to 15, wherein the abrasive particles are magnetically coated.

17. The abrasive article of any one of claims 1 to 16, wherein the patterned coating comprises repeating units.

18. The abrasive article of any one of claims 1 to 17, wherein the patterned coating extends from the center of the abrasive article to the edge of the abrasive article.

19. The abrasive article of any one of claims 1 to 18, wherein the abrasive article is an abrasive disc or an abrasive tape.

20. A method of making a coated abrasive article, the method comprising, in order:

depositing a curable make layer precursor on a major surface of the backing;

depositing a plurality of abrasive particles onto the curable make layer precursor;

at least partially curing the curable make layer precursor;

depositing a curable size layer precursor on the plurality of abrasive particles; and

at least partially curing the curable size layer precursor; and is

Wherein one of the curable make layer precursor and the curable size layer is deposited in a pattern on the major surface of the backing.

21. The method of claim 20, wherein the pattern comprises repeating units.

22. The method of any one of claims 20 to 21, wherein the pattern comprises lines, swirls, polygons, letters, or numbers.

23. The method of any of claims 20 to 22, wherein the pattern comprises a first color and a second color.

24. The method of claim 23, wherein the first color is a color of a cured size layer.

25. The method of claim 23, wherein the method further comprises depositing a supersize layer.

26. The method of claim 25, wherein the supersize layer is deposited in a supersize pattern, and wherein the second color comprises a supersize color.

27. The method of any one of claims 20 to 26, wherein the plurality of abrasive particles are deposited such that only a first portion of each abrasive particle is embedded within the curable make layer precursor and a second portion of each abrasive particle is free of make layer precursor.

28. The method of any one of claims 20 to 27, wherein the backing comprises a polymeric film, a metal foil, a woven fabric, a knitted fabric, paper, vulcanized fiber, a nonwoven, a foam, a screen, a mesh, or a combination thereof.

29. The method of any one of claims 20 to 28, and further comprising depositing a laminate coated directly to the first major surface of the backing, and wherein the make layer is bonded to the laminate.

30. A method according to any one of claims 20 to 29, and further comprising pre-treating the backing with a backsize, a presize or an impregnant.

31. The method of any one of claims 20 to 30, wherein the abrasive particles are deposited in a particle pattern.

32. The method of claim 31, wherein the particle pattern is different from the pattern.

33. The method of any one of claims 20 to 33, wherein the abrasive particles comprise crushed, plate, shaped or shaped abrasive particles.

34. The method of claim 33, wherein the abrasive particles are shaped abrasive particles, and wherein each of the shaped abrasive particles comprises at least one polygonal face.

35. The method of claim 35, wherein each of the shaped abrasive particles comprises at least one asymmetric surface.

36. The method of claim 34, wherein the abrasive particles are magnetically coated.

37. The method of claim 34, wherein the abrasive particles are aligned on the backing such that the at least one polygonal face of some of the shaped abrasive particles are aligned with respect to each other.

38. The method of claim 37, wherein the at least one polygonal face of some of the shaped abrasive particles is aligned with respect to the backing.

39. The method of claim 38, wherein the abrasive particles are angled relative to the backing.

Claims