WO2020128857A1 - Motif linéaire en quinconce pour articles abrasifs - Google Patents

Motif linéaire en quinconce pour articles abrasifs Download PDF

Info

Publication number
WO2020128857A1
WO2020128857A1 PCT/IB2019/060953 IB2019060953W WO2020128857A1 WO 2020128857 A1 WO2020128857 A1 WO 2020128857A1 IB 2019060953 W IB2019060953 W IB 2019060953W WO 2020128857 A1 WO2020128857 A1 WO 2020128857A1
Authority
WO
WIPO (PCT)
Prior art keywords
particles
row
abrasive article
particle
distance
Prior art date
Application number
PCT/IB2019/060953
Other languages
English (en)
Inventor
Joseph B. Eckel
Aaron K. NIENABER
Thomas J. Nelson
Ann M. Hawkins
Amelia W. KOENIG
Original Assignee
3M Innovative Properties Company
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 3M Innovative Properties Company filed Critical 3M Innovative Properties Company
Publication of WO2020128857A1 publication Critical patent/WO2020128857A1/fr

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24D—TOOLS FOR GRINDING, BUFFING OR SHARPENING
    • B24D18/00—Manufacture of grinding tools or other grinding devices, e.g. wheels, not otherwise provided for
    • B24D18/0072—Manufacture of grinding tools or other grinding devices, e.g. wheels, not otherwise provided for using adhesives for bonding abrasive particles or grinding elements to a support, e.g. by gluing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24D—TOOLS FOR GRINDING, BUFFING OR SHARPENING
    • B24D11/00—Constructional features of flexible abrasive materials; Special features in the manufacture of such materials
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24D—TOOLS FOR GRINDING, BUFFING OR SHARPENING
    • B24D2203/00—Tool surfaces formed with a pattern

Definitions

  • Abrasive particles and abrasive articles made from the abrasive particles are useful for abrading, finishing, or grinding a wide variety of materials and surfaces in the manufacturing of goods. For example, finishing of welding beads, flash, gates, and risers off castings by off-hand abrading with a handheld right-angle grinder is an important application for coated abrasive discs There continues to be a need for improving the cost, performance and other features of the abrasive articles.
  • FIGs. 1A-1B are schematic diagrams of shaped abrasive particles having a planar trigonal shape, in accordance with various embodiments.
  • FIGs. 2A-2E are schematic diagrams of shaped abrasive particles having a tetrahedral shape, in accordance with various embodiments.
  • FIGs. 3A and 3B are sectional views of coated abrasive articles, in accordance with various embodiments.
  • FIG. 4 is a schematic diagram showing a system for manufacturing abrasive articles in accordance with various embodiments.
  • FIG. 5 is a section of tooling from the system of FIG. 4 in accordance with various embodiments.
  • FIG. 6 is a top view of a coated abrasive belt.
  • FIG. 7 is a top view of a coated abrasive belt having staggered rows in accordance with various embodiments.
  • FIG. 8 is a top view of a coated abrasive disc.
  • FIG. 9 is a top view of a coated abrasive belt having staggered rows in accordance with various embodiments.
  • FIG. 10 is a schematic diagram showing particles aligned longitudinally and laterally on an abrasive article.
  • FIG. 11 is a schematic diagram showing particles in which adjacent rows are misaligned laterally on an abrasive article in accordance with various embodiments.
  • values expressed in a range format should be interpreted in a flexible manner to include not only the numerical values explicitly recited as the limits of the range, but also to include all the individual numerical values or sub-ranges encompassed within that range as if each numerical value and sub-range is explicitly recited.
  • a range of “about 0.1% to about 5%” or“about 0.1% to 5%” should be interpreted to include not just about 0.1% to about 5%, but also the individual values (e.g., 1%, 2%, 3%, and 4%) and the sub-ranges (e.g., 0.1% to 0.5%, 1.1% to 2.2%, 3.3% to 4.4%) within the indicated range.
  • the acts can be carried out in any order without departing from the principles of the disclosure, except when a temporal or operational sequence is explicitly recited. Furthermore, specified acts can be carried out concurrently unless explicit claim language recites that they be carried out separately. For example, a claimed act of doing X and a claimed act of doing Y can be conducted simultaneously within a single operation, and the resulting process will fall within the literal scope of the claimed process.
  • shaped abrasive particle means an abrasive particle having a predetermined or non-random shape.
  • One process to make a shaped abrasive particle such as a shaped ceramic abrasive particle includes shaping the precursor ceramic abrasive particle in a mold having a predetermined shape to make ceramic shaped abrasive particles.
  • Ceramic shaped abrasive particles, formed in a mold are one species in the genus of shaped ceramic abrasive particles.
  • Other processes to make other species of shaped ceramic abrasive particles include extruding the precursor ceramic abrasive particle through an orifice having a predetermined shape, printing the precursor ceramic abrasive particle though an opening in a printing screen having a predetermined shape, or embossing the precursor ceramic abrasive particle into a predetermined shape or patter.
  • the shaped ceramic abrasive particles can be cut from a sheet into individual particles. Examples of suitable cutting methods include mechanical cutting, laser cutting, or water-jet cutting.
  • Non-limiting examples of shaped ceramic abrasive particles include shaped abrasive particles, such as triangular plates, or elongated ceramic rods/filaments. Shaped ceramic abrasive particles are generally homogenous or substantially uniform and maintain their sintered shape without the use of a binder such as an organic or inorganic binder that bonds smaller abrasive particles into an agglomerated structure and excludes abrasive particles obtained by a crushing or comminution process that produces abrasive particles of random size and shape.
  • a binder such as an organic or inorganic binder that bonds smaller abrasive particles into an agglomerated structure and excludes abrasive particles obtained by a crushing or comminution process that produces abrasive particles of random size and shape.
  • the shaped ceramic abrasive particles comprise a homogeneous structure of sintered alpha alumina or consist essentially of sintered alpha alumina.
  • the present application discloses abrasive articles that include shaped abrasive particles, non-shaped abrasive particles or a combination thereof.
  • the abrasive articles can include staggered linear patterns formed on at least a portion of the abrasive article and such patterns can be formed by a linear arrangement of the particles on the abrasive article.
  • the staggered linear pattern can include a plurality of longitudinal rows that repeat across at least a portion of the abrasive article, and the longitudinal rows can be staggered relative to one another such that the particles in every other row are laterally aligned with one another, but particles in adjacent rows are laterally misaligned or staggered relative to one another.
  • the staggered linear patter can include a plurality of lateral rows that repeat across at least a portion of the abrasive article, and the lateral rows can be staggered relative to one another such that the particles in every other row are longitudinally aligned with one another, but particles in adjacent rows are longitudinally misaligned or staggered relative to one another.
  • Such design having staggered rows of particles can be applicable to abrasive articles in the form of sheets, discs, belts, pads, or rolls. As described further below, such design of an abrasive article having staggered rows of particles may provide one or more possible advantages.
  • FIGs. 1A and IB show an example of shaped abrasive particle 100, as an equilateral triangle conforming to a truncated pyramid.
  • shaped abrasive particle 100 includes a truncated regular triangular pyramid bounded by a triangular base 102, a triangular top 104, and plurality of sloping sides 106A, 106B, 106C connecting triangular base 102 (shown as equilateral although scalene, obtuse, isosceles, and right triangles are possible) and triangular top 104.
  • Slope angle 108A is the dihedral angle formed by the intersection of side 106A with triangular base 102.
  • slope angles 108B and 108C (both not shown) correspond to the dihedral angles formed by the respective intersections of sides 106B and 106C with triangular base 102. In the case of shaped abrasive particle 100, all of the slope angles have equal value.
  • side edges 110A, 110B, and 1 IOC have an average radius of curvature in a range of from about 0.5 mm to about 80 mm, about 10 mm to about 60 mm, or less than, equal to, or greater than about 0.5 mm, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, or about 80 mm.
  • sides 106A, 106B, and 106C have equal dimensions and form dihedral angles with the triangular base 102 of about 82 degrees
  • dihedral angle between the base and each of the sides may independently range from 45 to 90 degrees (for example, from 70 to 90 degrees, or from 75 to 85 degrees).
  • Edges connecting sides 106, base 102, and top 104 can have any suitable length.
  • a length of the edges may be in a range of from about 0.5 mm to about 2000 mm, about 150 mm to about 200 mm, or less than, equal to, or greater than about 0.5 mm, 50, 100, 150, 200, 250, 300, 350, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, 1100, 1150, 1200, 1250, 1300, 1350, 1400, 1450, 1500, 1550, 1600, 1650, 1700,
  • shaped abrasive particle 100 can have a length L defined between side edges 110A and HOC of the side 106A, and a height H defined between bottom edge of side 106A and side edge 110B.
  • the length L can be defined as the longest length among the sides 106.
  • a width W of the particle 100 can be defined between base 102 and top 104.
  • FIGs. 2A-2E are perspective views of the shaped abrasive particles 200 shaped as tetrahedral abrasive particles.
  • shaped abrasive particles 200 are shaped as regular tetrahedrons.
  • shaped abrasive particle 200A has four faces (220A, 222A, 224A, and 226A) joined by six edges (230A, 232A, 234A, 236A, 238 A, and 239 A) terminating at four vertices (240A, 242A, 244A, and 246A). Each of the faces contacts the other three of the faces at the edges.
  • tetrahedral abrasive particles 200 can be shaped as irregular tetrahedrons (e.g., having edges of differing lengths).
  • a length of tetrahedral abrasive particles 200 can be described as the longest length among the differing lengths.
  • shaped abrasive particle 200B has four faces (220B, 222B, 224B, and 226B) joined by six edges (230B, 232B, 234B, 236B, 238B, and 239B) terminating at four vertices (240B, 242B, 244B, and 246B).
  • Each of the faces is concave and contacts the other three of the faces at respective common edges.
  • a particle with tetrahedral symmetry e.g., four rotational axes of threefold symmetry and six reflective planes of symmetry
  • shaped abrasive particles 200B can have one, two, or three concave faces with the remainder being planar.
  • shaped abrasive particle 200C has four faces (220C, 222C, 224C, and 226C) joined by six edges (230C, 232C, 234C, 236C, 238C, and 239C) terminating at four vertices (240C, 242C, 244C, and 246C).
  • Each of the faces is convex and contacts the other three of the faces at respective common edges. While a particle with tetrahedral symmetry is depicted in FIG. 2C, it will be recognized that other shapes are also permissible.
  • shaped abrasive particles 200C can have one, two, or three convex faces with the remainder being planar or concave.
  • shaped abrasive particle 200D has four faces (220D, 222D, 224D, and 226D) joined by six edges (230D, 232D, 234D, 236D, 238D, and 239D) terminating at four vertices (240D, 242D, 244D, and 246D). While a particle with tetrahedral symmetry is depicted in FIG. 2D, it will be recognized that other shapes are also permissible. For example, shaped abrasive particles 200D can have one, two, or three convex faces with the remainder being planar.
  • Deviations from the depictions in FIGs. 2A-2D can be present.
  • An example of such a shaped abrasive particle 200 is depicted in FIG. 2E, showing shaped abrasive particle 200E, which has four faces (220E, 222E, 224E, and 226E) joined by six edges (230E, 232E, 234E, 236E, 238E, and 239E) terminating at four vertices (240E, 242E, 244E, and 246E). Each of the faces contacts the other three of the faces at respective common edges. Each of the faces, edges, and vertices has an irregular shape.
  • the edges can have the same length or different lengths.
  • the length of any of the edges can be any suitable length.
  • the length of the edges can be in a range of from about 0.5 mm to about 2000 mm, about 150 mm to about 200 mm, or less than, equal to, or greater than about 0.5 mm, 50, 100, 150, 200, 250, 300, 350, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, 1100, 1150, 1200, 1250, 1300, 1350, 1400, 1450, 1500, 1550, 1600, 1650, 1700, 1750, 1800, 1850, 1900, 1950, or about 2000 mm.
  • shaped abrasive particles 200A-200E can be the same size or different sizes. Any of shaped abrasive particles 100 or 200 can include any number of shape features.
  • the shape features can help to improve the cutting performance of any of shaped abrasive particles 100 or 200.
  • suitable shape features include an opening, a concave surface, a convex surface, a groove, a ridge, a fractured surface, a low roundness factor, or a perimeter comprising one or more comer points having a sharp tip.
  • Individual shaped abrasive particles can include any one or more of these features.
  • At least one magnetic material may be included within or coated to shaped abrasive particle 100 or 200.
  • magnetic materials include iron; cobalt; nickel; various alloys of nickel and iron marketed as Permalloy in various grades; various alloys of iron, nickel and cobalt marketed as Femico, Kovar, FerNiCo I, or FerNiCo II; various alloys of iron, aluminum, nickel, cobalt, and sometimes also copper and/or titanium marketed as Alnico in various grades; alloys of iron, silicon, and aluminum (about 85:9:6 by weight) marketed as Sendust alloy; Heusler alloys (e.g., Cu 2 MnSn); manganese bismuthide (also known as Bismanol); rare earth magnetizable materials such as gadolinium, dysprosium, holmium, europium oxide, alloys of neodymium, iron and boron (e.g., Nd 2 Fe 14 B).
  • samarium and cobalt e.g., SmCo 5
  • MnSb MnOFe 2 O 3
  • Y Fe 5 O 12 CrO 2 MnAs
  • ferrites such as ferrite, magnetite; zinc ferrite; nickel ferrite; cobalt ferrite, magnesium ferrite, barium ferrite, and strontium ferrite; yttrium iron garnet; and combinations of the foregoing.
  • the magnetizable material is an alloy containing 8 to 12 weight percent aluminum, 15 to 26 wt% nickel, 5 to 24 wt% cobalt, up to 6 wt% copper, up to 1 % titanium, wherein the balance of material to add up to 100 wt% is iron.
  • a magnetizable coating can be deposited on an abrasive particle 100 using a vapor deposition technique such as, for example, physical vapor deposition (PVD) including magnetron sputtering.
  • PVD physical vapor deposition
  • Including these magnetizable materials can allow shaped abrasive particle 100 or 200 to be responsive a magnetic field. Any of shaped abrasive particles 100 or 200 can include the same material or include different materials.
  • Shaped abrasive particle 100 or 200 can be formed in many suitable manners for example, the shaped abrasive particle 100 or 200 can be made according to a multi -operation process.
  • the process can be carried out using any material or precursor dispersion material.
  • the process can include the operations of making either a seeded or non-seeded precursor dispersion that can be converted into a corresponding (e.g., a boehmite sol-gel that can be converted to alpha alumina); fdling one or more mold cavities having the desired outer shape of shaped abrasive particle 100 with a precursor dispersion; drying the precursor dispersion to form precursor shaped abrasive particle; removing the precursor shaped abrasive particle 100 from the mold cavities; calcining the precursor shaped abrasive particle 100 to form calcined, precursor shaped abrasive particle 100 or 200; and then s
  • the mold cavities may be fdled with a melamine to form melamine shaped abrasive particles.
  • the process can include the operation of providing either a seeded or non-seeded dispersion of a precursor that can be converted into ceramic.
  • the precursor can be seeded with an oxide of an iron (e.g., FeO).
  • the precursor dispersion can include a liquid that is a volatile component.
  • the volatile component is water.
  • the dispersion can include a sufficient amount of liquid for the viscosity of the dispersion to be sufficiently low to allow filling mold cavities and replicating the mold surfaces, but not so much liquid as to cause subsequent removal of the liquid from the mold cavity to be prohibitively expensive.
  • the precursor dispersion includes from 2 percent to 90 percent by weight of the particles that can be converted into ceramic, such as particles of aluminum oxide monohydrate (boehmite), and at least 10 percent by weight, or from 50 percent to 70 percent, or 50 percent to 60 percent, by weight, of the volatile component such as water.
  • the precursor dispersion in some embodiments contains from 30 percent to 50 percent, or 40 percent to 50 percent solids by weight.
  • Suitable precursor dispersions include zirconium oxide sols, vanadium oxide sols, cerium oxide sols, aluminum oxide sols, and combinations thereof.
  • Suitable aluminum oxide dispersions include, for example, boehmite dispersions and other aluminum oxide hydrates dispersions. Boehmite can be prepared by known techniques or can be obtained commercially. Examples of commercially available boehmite include products having the trade designations “DISPERAL” and“DISPAL”, both available from Sasol North America, Inc., or“HIQ-40” available from BASF Corporation. These aluminum oxide monohydrates are relatively pure; that is, they include relatively little, if any, hydrate phases other than monohydrates, and have a high surface area.
  • the physical properties of the resulting shaped abrasive particle 100 or 200 can generally depend upon the type of material used in the precursor dispersion.
  • a“gel” is a three-dimensional network of solids dispersed in a liquid.
  • the precursor dispersion can contain a modifying additive or precursor of a modifying additive.
  • the modifying additive can function to enhance some desirable property of the abrasive particles or increase the effectiveness of the subsequent sintering step.
  • Modifying additives or precursors of modifying additives can be in the form of soluble salts, such as water-soluble salts.
  • They can include a metal-containing compound and can be a precursor of an oxide of magnesium, zinc, iron, silicon, cobalt, nickel, zirconium, hafnium, chromium, yttrium, praseodymium, samarium, ytterbium, neodymium, lanthanum, gadolinium, cerium, dysprosium, erbium, titanium, and mixtures thereof.
  • concentrations of these additives that can be present in the precursor dispersion can be varied.
  • the introduction of a modifying additive or precursor of a modifying additive can cause the precursor dispersion to gel.
  • the precursor dispersion can also be induced to gel by application of heat over a period of time to reduce the liquid content in the dispersion through evaporation.
  • the precursor dispersion can also contain a nucleating agent.
  • Nucleating agents suitable for this disclosure can include fine particles of alpha alumina, alpha ferric oxide or its precursor, titanium oxides and titanates, chrome oxides, or any other material that will nucleate the transformation.
  • the amount of nucleating agent, if used, should be sufficient to effect the transformation of alpha alumina.
  • a peptizing agent can be added to the precursor dispersion to produce a more stable hydrosol or colloidal precursor dispersion.
  • Suitable peptizing agents are monoprotic acids or acid compounds such as acetic acid, hydrochloric acid, formic acid, and nitric acid. Multiprotic acids can also be used, but they can rapidly gel the precursor dispersion, making it difficult to handle or to introduce additional components.
  • Some commercial sources of boehmite contain an acid titer (such as absorbed formic or nitric acid) that will assist in forming a stable precursor dispersion.
  • the precursor dispersion can be formed by any suitable means; for example, in the case of a sol-gel alumina precursor, it can be formed by simply mixing aluminum oxide monohydrate with water containing a peptizing agent or by forming an aluminum oxide monohydrate slurry to which the peptizing agent is added.
  • Defoamers or other suitable chemicals can be added to reduce the tendency to form bubbles or entrain air while mixing. Additional chemicals such as wetting agents, alcohols, or coupling agents can be added if desired.
  • a further operation can include providing a mold having at least one mold cavity, or a plurality of cavities formed in at least one major surface of the mold.
  • the mold is formed as a production tool, which can be, for example, a belt, a sheet, a continuous web, a coating roll such as a rotogravure roll, a sleeve mounted on a coating roll, or a die.
  • the production tool can include polymeric material.
  • suitable polymeric materials include thermoplastics such as polyesters, polycarbonates, poly(ether sulfone), poly(methyl methacrylate), polyurethanes, polyvinylchloride, polyolefin, polystyrene, polypropylene, polyethylene or combinations thereof, or thermosetting materials.
  • the entire tooling is made from a polymeric or thermoplastic material.
  • the surfaces of the tooling in contact with the precursor dispersion while the precursor dispersion is drying, such as the surfaces of the plurality of cavities include polymeric or thermoplastic materials, and other portions of the tooling can be made from other materials.
  • a suitable polymeric coating can be applied to a metal tooling to change its surface tension properties, by way of example.
  • a polymeric or thermoplastic production tool can be replicated off a metal master tool.
  • the master tool can have the inverse pattern of that desired for the production tool.
  • the master tool can be made in the same manner as the production tool.
  • the master tool is made out of metal (e.g., nickel) and is diamond-turned.
  • the master tool is at least partially formed using stereolithography.
  • the polymeric sheet material can be heated along with the master tool such that the polymeric material is embossed with the master tool pattern by pressing the two together.
  • a polymeric or thermoplastic material can also be extruded or cast onto the master tool and then pressed.
  • the thermoplastic material is cooled to solidify and produce the production tool. If a thermoplastic production tool is utilized, then care should be taken not to generate excessive heat that can distort the thermoplastic production tool, limiting its life.
  • Access to cavities can be from an opening in the top surface or bottom surface of the mold.
  • the cavities can extend for the entire thickness of the mold.
  • the cavities can extend only for a portion of the thickness of the mold.
  • the top surface is substantially parallel to the bottom surface of the mold with the cavities having a substantially uniform depth.
  • At least one side of the mold, the side in which the cavities are formed, can remain exposed to the surrounding atmosphere during the step in which the volatile component is removed.
  • the cavities have a specified three-dimensional shape to make shaped abrasive particle 100.
  • the depth dimension is equal to the perpendicular distance from the top surface to the lowermost point on the bottom surface.
  • the depth of a given cavity can be uniform or can vary along its length and/or width.
  • the cavities of a given mold can be of the same shape or of different shapes.
  • a further operation involves filling the cavities in the mold with the precursor dispersion (e.g., by a conventional technique).
  • a knife roll coater or vacuum slot die coater can be used.
  • a mold release agent can be used to aid in removing the particles from the mold if desired. Examples of mold release agents include oils such as peanut oil or mineral oil, fish oil, silicones, polytetrafluoroethylene, zinc stearate, and graphite.
  • a mold release agent such as peanut oil, in a liquid, such as water or alcohol, is applied to the surfaces of the production tooling in contact with the precursor dispersion such that from about 0.1 mg/in 2 (0.6 mg/cm 2 ) to about 3.0 mg/in 2 (20 mg/cm 2 ), or from about 0.1 mg/in 2 (0.6 mg/cm 2 ) to about 5.0 mg/in 2 (30 mg/cm 2 ), of the mold release agent is present per unit area of the mold when a mold release is desired.
  • the top surface of the mold is coated with the precursor dispersion. The precursor dispersion can be pumped onto the top surface.
  • a scraper or leveler bar can be used to force the precursor dispersion fully into the cavity of the mold.
  • the remaining portion of the precursor dispersion that does not enter the cavity can be removed from the top surface of the mold and recycled.
  • a small portion of the precursor dispersion can remain on the top surface, and in other examples the top surface is substantially free of the dispersion.
  • the pressure applied by the scraper or leveler bar can be less than 100 psi (0.6 MPa), or less than 50 psi (0.3 MPa), or even less than 10 psi (60 kPa). In some examples, no exposed surface of the precursor dispersion extends substantially beyond the top surface.
  • a further operation involves removing the volatile component to dry the dispersion.
  • the volatile component can be removed by fast evaporation rates. In some examples, removal of the volatile component by evaporation occurs at temperatures above the boiling point of the volatile component.
  • An upper limit to the drying temperature often depends on the material the mold is made from. For polypropylene tooling, the temperature should be less than the melting point of the plastic. In one example, for a water dispersion of from about 40 to 50 percent solids and a polypropylene mold, the drying temperatures can be from about 90° C to about 165° C, or from about 105° C to about 150° C, or from about 105° C to about 120° C. Higher temperatures can lead to improved production speeds but can also lead to degradation of the polypropylene tooling, limiting its useful life as a mold.
  • the precursor dispersion shrinks, often causing retraction from the cavity walls.
  • the resulting shaped abrasive particle 100 can tend to have at least three concave major sides. It is presently discovered that by making the cavity walls concave (whereby the cavity volume is increased) it is possible to obtain shaped abrasive particle 100 that have at least three substantially planar major sides.
  • the degree of concavity generally depends on the solids content of the precursor dispersion.
  • a further operation involves removing resultant precursor shaped abrasive particle 100 from the mold cavities.
  • the precursor shaped abrasive particle 100 or 200 can be removed from the cavities by using the following processes alone or in combination on the mold: gravity, vibration, ultrasonic vibration, vacuum, or pressurized air to remove the particles from the mold cavities.
  • the precursor shaped abrasive particle 100 or 200 can be further dried outside of the mold. If the precursor dispersion is dried to the desired level in the mold, this additional drying step is not necessary. However, in some instances it can be economical to employ this additional drying step to minimize the time that the precursor dispersion resides in the mold.
  • the precursor shaped abrasive particle 100 or 200 will be dried from 10 to 480 minutes, or from 120 to 400 minutes, at a temperature from 50° C to 160° C, or 120° C to 150° C.
  • a further operation involves calcining the precursor shaped abrasive particle 100 or 200.
  • calcining essentially all the volatile material is removed, and the various components that were present in the precursor dispersion are transformed into metal oxides.
  • the precursor shaped abrasive particle 100 or 200 is generally heated to a temperature from 400° C to 800° C and maintained within this temperature range until the free water and over 90 percent by weight of any bound volatile material are removed.
  • a water-soluble salt can be introduced by impregnation into the pores of the calcined, precursor shaped abrasive particle 100. Then the precursor shaped abrasive particle 100 are pre-fired again.
  • a further operation can involve sintering the calcined, precursor shaped abrasive particle 100 or 200 to form particles 100 or 200.
  • the precursor includes rare earth metals, however, sintering may not be necessary.
  • the calcined, precursor shaped abrasive particle 100 or 200 are not completely densified and thus lack the desired hardness to be used as shaped abrasive particle 100 or 200.
  • Sintering takes place by heating the calcined, precursor shaped abrasive particle 100 or 200 to a temperature of from 1000° C to 1650° C.
  • the length of time for which the calcined, precursor shaped abrasive particle 100 or 200 can be exposed to the sintering temperature to achieve this level of conversion depends upon various factors, but from five seconds to 48 hours is possible.
  • the duration of the sintering step ranges from one minute to 90 minutes.
  • the shaped abrasive particle 14 can have a Vickers hardness of 10 GPa (gigaPascals), 16 GPa, 18 GPa, 20 GPa, or greater.
  • Additional operations can be used to modify the described process, such as, for example, rapidly heating the material from the calcining temperature to the sintering temperature, and centrifuging the precursor dispersion to remove sludge and/or waste.
  • the process can be modified by combining two or more of the process steps if desired.
  • FIG. 3 A is a sectional view of coated abrasive article 300.
  • Coated abrasive article 300 includes backing 302 defining a surface along an x-y direction.
  • Backing 302 has a first layer of binder, hereinafter referred to as make coat 304, applied over a first surface of backing 302.
  • Attached or partially embedded in make coat 304 are a plurality of shaped abrasive particles 200A. Although shaped abrasive particles 200A are shown any other shaped abrasive particle described herein can be included in coated abrasive article 300.
  • An optional second layer of binder, hereinafter referred to as size coat 306, is dispersed over shaped abrasive particles 200A. As shown, a major portion of shaped abrasive particles 200A have at least one of three vertices (240, 242, and 244) oriented in substantially the same direction.
  • shaped abrasive particles 200A are oriented according to a non-random distribution, although in other embodiments any of shaped abrasive particles 200A can be randomly oriented on backing 302. In some embodiments, control of a particle’s orientation can increase the cut of the abrasive article.
  • Backing 302 can be flexible or rigid. Examples of suitable materials for forming a flexible backing include a polymeric film, a metal foil, a woven fabric, a knitted fabric, paper, vulcanized fiber, a staple fiber, a continuous fiber, a nonwoven, a foam, a screen, a laminate, and combinations thereof. Backing 302 can be shaped to allow coated abrasive article 300 to be in the form of sheets, discs, belts, pads, or rolls. In some embodiments, backing 302 can be sufficiently flexible to allow coated abrasive article 300 to be formed into a loop to make an abrasive belt that can be run on suitable grinding equipment.
  • Make coat 304 secures shaped abrasive particles 200A to backing 302, and size coat 306 can help to reinforce shaped abrasive particles 200A.
  • Make coat 304 and/or size coat 306 can include a resinous adhesive.
  • the resinous adhesive can include one or more resins chosen from a phenolic resin, an epoxy resin, a urea-formaldehyde resin, an acrylate resin, an aminoplast resin, a melamine resin, an acrylated epoxy resin, a urethane resin, a polyester resin, a dying oil, and mixtures thereof.
  • FIG. 3B shows an example of coated abrasive article 300B, which includes shaped abrasive particles 100 instead of shaped abrasive particles 200.
  • shaped abrasive particles 100 are attached to backing 302 by make coat 304 with size coat 306 applied to further attach or adhere shaped abrasive particles 100 to the backing 302.
  • size coat 306 applied to further attach or adhere shaped abrasive particles 100 to the backing 302.
  • the majority of the shaped abrasive particles 100 are tipped or leaning to one side. This results in the majority of shaped abrasive particles 100 having an orientation angle b less than 90 degrees relative to backing 302.
  • Abrasive article 300 can also include conventional (e.g., crushed) abrasive particles.
  • useful abrasive particles include fused aluminum oxide-based materials such as aluminum oxide, ceramic aluminum oxide (which can include one or more metal oxide modifiers and/or seeding or nucleating agents), and heat-treated aluminum oxide, silicon carbide, co-fused alumina-zirconia, diamond, ceria, titanium diboride, cubic boron nitride, boron carbide, garnet, flint, emery, sol-gel derived abrasive particles, and mixtures thereof.
  • fused aluminum oxide-based materials such as aluminum oxide, ceramic aluminum oxide (which can include one or more metal oxide modifiers and/or seeding or nucleating agents), and heat-treated aluminum oxide, silicon carbide, co-fused alumina-zirconia, diamond, ceria, titanium diboride, cubic boron nitride, boron carbide, garnet, flint, e
  • the conventional abrasive particles can, for example, have an average diameter ranging from about 10 mm to about 2000 mm, about 20 mm to about 1300 mm, about 50 mm to about 1000 mm, less than, equal to, or greater than about 10 mm, 20, 30, 40, 50, 100, 150, 200, 250, 300, 350, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 1050, 1100, 1150, 1200, 1250, 1300, 1350, 1400, 1450, 1500, 1550, 1650, 1700, 1750, 1800, 1850, 1900, 1950, or 2000 mm.
  • the conventional abrasive particles can have an abrasives industry-specified nominal grade.
  • abrasives industry-accepted grading standards include those known as the American National Standards Institute, Inc. (ANSI) standards, Federation of European Producers of Abrasive Products (FEPA) standards, and Japanese Industrial Standard (HS) standards.
  • Exemplary ANSI grade designations include: ANSI 12 (1842 mm), ANSI 16 (1320 mm), ANSI 20 (905 mm), ANSI 24 (728 mm), ANSI 36 (530 mm), ANSI 40 (420 mm), ANSI 50 (351 mm), ANSI 60 (264 mm), ANSI 80 (195 mm), ANSI 100 (141 mm), ANSI 120 (116 mm), ANSI 150 (93 mm), ANSI 180 (78 mm), ANSI 220 (66 mm), ANSI 240 (53 mm), ANSI 280 (44 mm), ANSI 320 (46 mm), ANSI 360 (30 mm), ANSI 400 (24 mm), and ANSI 600 (16 mm).
  • Exemplary FEPA grade designations include P12 (1746 mm), P16 (1320 mm), P20 (984 mm), P24 (728 mm), P30 (630 mm), P36 (530 mm), P40 (420 mm), P50 (326 mm), P60 (264 mm), P80 (195 mm), P100 (156 mm), P120 (127 mm), P120 (127 mm), P150 (97 mm), P180 (78 mm), P220 (66 mm), P240 (60 mm), P280 (53 mm), P320 (46 mm), P360 (41 mm), P400 (36 mm), P500 (30 mm), P600 (26 mm), and P800 (22 mm).
  • An approximate average particles size of reach grade is listed in parenthesis following each grade designation.
  • Shaped abrasive particles 100 or 200 or crushed abrasive particles can include any suitable material or mixture of materials.
  • shaped abrasive particles 100 can include a material chosen from an alpha-alumina, a fused aluminum oxide, a heat-treated aluminum oxide, a ceramic aluminum oxide, a sintered aluminum oxide, a silicon carbide, a titanium diboride, a boron carbide, a tungsten carbide, a titanium carbide, a diamond, a cubic boron nitride, a garnet, a fused alumina-zirconia, a sol-gel derived abrasive particle, a cerium oxide, a zirconium oxide, a titanium oxide, and combinations thereof.
  • shaped abrasive particles 100 or 200 and crushed abrasive particles can include the same materials.
  • shaped abrasive particles 100 or 200 and crushed abrasive particles can include different materials.
  • Filler particles can also be included in abrasive articles 200 or 300.
  • useful fillers include metal carbonates (such as calcium carbonate, calcium magnesium carbonate, sodium carbonate, magnesium carbonate), silica (such as quartz, glass beads, glass bubbles and glass fibers), silicates (such as talc, clays, montmorillonite, feldspar, mica, calcium silicate, calcium metasilicate, sodium aluminosilicate, sodium silicate), metal sulfates (such as calcium sulfate, barium sulfate, sodium sulfate, aluminum sodium sulfate, aluminum sulfate), gypsum, vermiculite, sugar, wood flour, a hydrated aluminum compound, carbon black, metal oxides (such as calcium oxide, aluminum oxide, tin oxide, titanium dioxide), metal sulfites (such as calcium sulfite), thermoplastic particles (such as polycarbonate, polyetherimide, polyester, polyethylene, poly(vinylchloride), polys
  • metal fillers include, tin, lead, bismuth, cobalt, antimony, cadmium, iron and titanium.
  • Other miscellaneous fillers include sulfur, organic sulfur compounds, graphite, lithium stearate and metallic sulfides.
  • individual shaped abrasive particles 100 or individual crushed abrasive particles can be at least partially coated with an amorphous, ceramic, or organic coating.
  • suitable components of the coatings include, a silane, glass, iron oxide, aluminum oxide, or combinations thereof. Coatings such as these can aid in processability and bonding of the particles to a resin of a binder.
  • Some shaped abrasive particles 100 or 200 can include a polymeric material and can be characterized as soft abrasive particles.
  • the soft shaped abrasive particles described herein can independently include any suitable material or combination of materials.
  • the soft shaped abrasive particles can include a reaction product of a polymerizable mixture including one or more polymerizable resins.
  • the one or more polymerizable resins such as a hydrocarbyl polymerizable resin.
  • Such resins include those chosen from a phenolic resin, a urea formaldehyde resin, a urethane resin, a melamine resin, an epoxy resin, a bismaleimide resin, a vinyl ether resin, an aminoplast resin (which may include pendant alpha, beta unsaturated carbonyl groups), an acrylate resin, an acrylated isocyanurate resin, an isocyanurate resin, an acrylated urethane resin, an acrylated epoxy resin, an alkyl resin, a polyester resin, a drying oil, or mixtures thereof.
  • the polymerizable mixture can include additional components such as a plasticizer, an acid catalyst, a cross-linker, a surfactant, a mild-abrasive, a pigment, a catalyst and an antibacterial agent.
  • the polymerizable resin or resins may be in a range of from about 35 wt% to about 99.9 wt% of the polymerizable mixture, about 40 wt% to about 95 wt%, or less than, equal to, or greater than about 35 wt%, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92,
  • the cross-linker may be in a range of from about 2 wt% to about 60 wt% of the polymerizable mixture, from about 5 wt% to about 10 wt%, or less than, equal to, or greater than about 2 wt%, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or about 15 wt%.
  • suitable cross linkers include a cross-linker available under the trade designation CYMEL 303 LF, of Allnex USA Inc., Alpharetta, Georgia, USA; or a cross-linker available under the trade designation CYMEL 385, of Allnex USA Inc., Alpharetta, Georgia, USA.
  • the mild-abrasive may be in a range of from about 5 wt% to about 65 wt% of the polymerizable mixture, about 10 wt% to about 20 wt%, or less than, equal to, or greater than about 5 wt%, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29
  • suitable mild-abrasive s include a mild-abrasive available under the trade designation MINSTRON 353 TALC, of Imerys Talc America, Inc., Three Forks, Montana, USA; a mild-abrasive available under the trade designation USG TERRA ALBA NO.l CALCIUM SULFATE, of USG Corporation, Chicago, Illinois, USA; Recycled Glass (40-70 Grit) available from ESCA Industries, Ltd., Hatfield, Pennsylvania, USA, silica, calcite, nephebne, syenite, calcium carbonate, or mixtures thereof.
  • MINSTRON 353 TALC of Imerys Talc America, Inc., Three Forks, Montana, USA
  • USG TERRA ALBA NO.l CALCIUM SULFATE of USG Corporation, Chicago, Illinois, USA
  • Recycled Glass (40-70 Grit) available from ESCA Industries, Ltd., Hatfield, Pennsylvania, USA, silica, calcite,
  • the plasticizer may be in a range of from about 5 wt% to about 40 wt% of the polymerizable mixture, about 10 wt% to about 15 wt%, or less than, equal to, or greater than about 5 wt%, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30,
  • suitable plasticizers include acrylic resins or styrene butadiene resins.
  • acrylic resins include an acrylic resin available under the trade designation RHOPLEX GL-618, of DOW Chemical Company, Midland, Michigan, USA; an acrylic resin available under the trade designation HYCAR 2679, of the Lubrizol Corporation, Wickliffe, Ohio, USA; an acrylic resin available under the trade designation HYCAR 26796, of the Lubrizol Corporation, Wickliffe, Ohio, USA; a polyether polyol available under the trade designation ARCOL LG-650, of DOW Chemical Company, Midland, Michigan, USA; or an acrylic resin available under the trade designation HY CAR 26315, of the Lubrizol Corporation, Wickliffe, Ohio, USA.
  • An example of a styrene butadiene resin includes a resin available under the trade designation ROVENE 5900, of Mallard Creek Polymers, Inc., Charlotte, North Carolina,
  • the acid catalyst may be in a range of from 0.5 wt% to about 20 wt% of the polymerizable mixture, about 5 wt% to about 10 wt%, or less than, equal to, or greater than about 1 wt%, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or about 20 wt%.
  • suitable acid catalysts include a solution of aluminum chloride or a solution of ammonium chloride.
  • the surfactant can be in a range of from about 0.001 wt% to about 15 wt% of the polymerizable mixture about 5 wt% to about 10 wt%, less than, equal to, or greater than about 0.001 wt%, 0.01, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or about 15 wt%.
  • surfactants examples include a surfactant available under the trade designation GEMTEX SC-85-P, of Innospec Performance Chemicals, Salisbury, North Carolina, USA; a surfactant available under the trade designation DYNOL 604, of Air Products and Chemicals, Inc., Allentown, Pennsylvania, USA; a surfactant available under the trade designation ACRYSOL RM-8W, of DOW Chemical Company, Midland, Michigan, USA; or a surfactant available under the trade designation
  • the antimicrobial agent may be in a range of from 0.5 wt% to about 20 wt% of the polymerizable mixture, about 10 wt% to about 15 wt%, or less than, equal to, or greater than about 0.5 wt%, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or about 20 wt%.
  • An example of a suitable antimicrobial agent includes zinc pyrithione.
  • the pigment may be in a range of from about 0.1 wt% to about 10 wt% of the polymerizable mixture, about 3 wt% to about 5 wt%, less than, equal to, or greater than about 0.1 wt%, 0.2, 0.4, 0.6, 0.8, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, or about 10 wt%.
  • suitable pigments include a pigment dispersion available under the trade designation SUNSPERSE BLUE 15, of Sun Chemical Corporation, Parsippany, New Jersey, USA; a pigment dispersion available under the trade designation SUNSPERSE VIOLET 23, of Sun Chemical Corporation, Parsippany, New Jersey, USA; a pigment dispersion available under the trade designation SUN BLACK, of Sun Chemical Corporation, Parsippany, New Jersey, USA; or a pigment dispersion available under the trade designation BLUE PIGMENT B2G, of Clariant Ltd., Charlotte, North Carolina, USA.
  • the mixture of components can be polymerized by curing.
  • each of the plurality of shaped abrasive particles 100 or 200 can have a specified z-direction rotational orientation about a z-axis passing through shaped abrasive particles 100 or 200 and through backing 302 at a 90 degree angle to backing 302.
  • Shaped abrasive particles 100 or 200 are orientated with a surface feature, such as a substantially planar surface particle 100 or 200, rotated into a specified angular position about the z-axis.
  • the specified z-direction rotational orientation abrasive article 300A or 300B occurs more frequently than would occur by a random z-directional rotational orientation of the surface feature due to electrostatic coating or drop coating of the shaped abrasive particles 100 or 200 when forming the abrasive article 300A or 300B.
  • the cut rate, finish, or both of coated abrasive article 300A or 300B can be varied from those manufactured using an electrostatic coating method.
  • At least 50, 51, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 99 percent of shaped abrasive particles 100 or 200 can have a specified z-direction rotational orientation which does not occur randomly and which can be substantially the same for all of the aligned particles.
  • about 50 percent of shaped abrasive particles 100 or 200 can be aligned in a first direction and about 50 percent of shaped abrasive particles 100 or 200 can be aligned in a second direction.
  • the first direction is substantially orthogonal to the second direction.
  • the specific z-direction rotational orientation of formed abrasive particles can be achieved through use of a precision apertured screen that positions shaped abrasive particles 100 or 200 into a specific z-direction rotational orientation such that shaped abrasive particle 100 or 200 can only fit into the precision apertured screen in a few specific orientations such as less than or equal to 4, 3, 2, or 1 orientations.
  • a rectangular opening just slightly bigger than the cross section of shaped abrasive particle 100 or 200 comprising a rectangular plate will orient shaped abrasive particle 100 or 200 in one of two possible 180 degree opposed z-direction rotational orientations.
  • the precision apertured screen can be designed such that shaped abrasive particles 100 or 200, while positioned in the screen's apertures, can rotate about their z-axis (normal to the screen's surface when the formed abrasive particles are positioned in the aperture) less than or equal to about 30, 20, 10, 5, 2, or 1 angular degrees.
  • the precision apertured screen having a plurality of apertures selected to z-directionally orient shaped abrasive particles 100 and 200 into a pattern, can have a retaining member such as adhesive tape on a second precision apertured screen with a matching aperture pattern, an electrostatic field used to hold the particles in the first precision screen or a mechanical lock such as two precision apertured screens with matching aperture patterns twisted in opposite directions to pinch particles 100 and 200 within the apertures.
  • the first precision aperture screen is filled with shaped abrasive particles 100 and 200, and the retaining member is used to hold shaped abrasive particles 100 in place in the apertures.
  • adhesive tape on the surface of a second precision aperture screen aligned in a stack with the first precision aperture screen causes shaped abrasive particles 100 to stay in the apertures of the first precision screen stuck to the surface of the tape exposed in the second precision aperture screen's apertures.
  • coated backing 302 having make layer 304 is positioned parallel to the first precision aperture screen surface containing the shaped abrasive paitides 100 or 200 with make layer 304 facing shaped abrasive paitides 100 or 200 in the apertures. Thereafter, coated backing 302 and the first predsion aperture screen are brought into contact to adhere shaped abrasive particles 100 or 200 to the make layer. The retaining member is released such as removing the second predsion aperture screen with taped surface, untwisting the two predsion aperture screens, or eliminating the electrostatic field.
  • the first precision aperture screen is then removed leaving the shaped abrasive particles 100 or 200 having a specified z-directianal rotational orientation on the coated abrasive article 300 for further conventional processing such as applying a size coat and curing the make and size coats.
  • the curable binder precursor comprises a make layer precursor
  • the magnetizable particles comprise magnetizable abrasive particles.
  • a size layer precursor may be applied over the at least partially cured make layer precursor and the magnetizable abrasive particles, although this is not a requirement. If present, the size layer precursor is then at least partially cured at a second curing station, optionally with further curing of the at least partially cured make layer precursor. In some embodiments, a supersize layer is disposed on the at least partially cured size layer precursor.
  • coated abrasive article system 1300 includes shaped abrasive paitides 1302 removably disposed within cavities 1402 of production tool 1350 having first web path 1304 guiding production tool 1350 through system 1300 such that it wraps a portion of an outer circumference of shaped abrasive particle transfer roll 1308.
  • System 1300 can include, for example, idler rollers 1310 and make coat delivery system 1312.
  • Second web path 1306 for resin coated backing 1314 passes through the system 1300 such that the resin layer is positioned feeing a dispensing surface 1404 (FIG. 5) of production tool 1350 that is positioned between resin coated backing 1314 and an outer circumference of the shaped abrasive particle transfer roll 1308.
  • Make coat delivery system 1312 can be a simple pan or reservoir containing the make coat resin or a pumping system with a storage tank and delivery plumbing to translate make coat resin 1316 to a needed location.
  • Backing 1314 can be a cloth, paper, film, nonwoven, scrim, or other web substrate.
  • Make coat applicator 1312 can be, for example, a coater, a roll coaler, a spray system, a die coater, or a rod coater.
  • a pre-coated coated backing can be positioned by an idler roll 1310 for application of shaped abrasive particles 1302 to the first major surface.
  • production tool 1350 comprises a plurality of cavities 1402 having a complimentary shape to intended shaped abrasive particle 1302 to be contained therein.
  • Shaped abrasive particle feeder 1320 supplies at least some shaped abrasive particles 1302 to production tool 1350.
  • Shaped abrasive particle feeder 1320 can supply an excess of shaped abrasive particles 1302 such that there are more shaped abrasive particles 1302 present per unit length of production tool in the machine direction than cavities 1402 present Supplying an excess of shaped abrasive partides 1302 helps to ensure that a desired number of cavities 1402 within the production tool 1350 are eventually filled with shaped abrasive particle 1302.
  • Shaped abrasive particle feeder 1320 can be the same width as the production tool 1350 and can supply shaped abrasive particles 1302 across the entire width of production tool 1350.
  • Shaped abrasive particle feeder 1320 can be, for example, a vibratory feeder, a hopper, a chute, a silo, a drop coater, or a screw feeder.
  • filling assist system 1330 is provided after shaped abrasive moussee feeder 1320 to move shaped abrasive particles 1302 around on the surface of production tool 1350 and to help orientate or slide shaped abrasive partides 1302 into the cavities 1402.
  • Filling assist system 1330 can be, for example, a doctor blade, a felt wiper, a brash having a plurality of bristles, a vibration system, a blower or air knife, a vacuum box, or combinations thereof.
  • Filling assist system 1330 moves, translates, sucks, or agitates shaped abrasive partides 1302 on dispensing surface 1404 (top or upper surface of production tool 1350 in FIG. 4) to place more shaped abrasive partides 1302 into cavities 1402.
  • Without filling assist system 1330 generally at least some of shaped abrasive particles 1302 dropped onto dispensing
  • filling assist system 1330 can be oscillated laterally in the cross direction or otherwise have a relative motion such as circular or oval to the surface of production tool 1350 using a suitable drive to assist in completely filling each cavity 1402 in production tool 1350 with a shaped abrasive particle 1302.
  • the bristles may cover a section of dispensing surface 1404 from 2-60 inches (5.0-153 cm) in length in the machine direction across all or most all of the width of dispensing surface 1404, and lightly rest on or just above dispensing surface 1404, and be of a moderate flexibility.
  • Vacuum box 1332 if included in the filling assist system 1330, can be in conjunction with production tool 1350 having cavities 1402 extending completely through production tool 1350.
  • Vacuum box may be located near shaped abrasive particle feeder 1320 and may be located before or after shaped abrasive particle feeder 1320, or encompass any portion of a web span between a pair of idler rolls 1310 in the shaped abrasive particle filling and excess removal section of the apparatus.
  • production tool 1350 can be supported or pushed on by a shoe or a plate to assist in keeping it planar in this section of the apparatus instead or in addition to vacuum box 1332.
  • FIG. 4 it is possible to include one or more components in system 1330 to remove excess shaped abrasive particles 1302, in some embodiments it may be possible to include only one component in system 1330.
  • shaped abrasive particles 1302 in production tool 1350 travel towards resin coated backing 1314.
  • Shaped abrasive particle transfer roll 1308 is provided and production
  • tooling 1350 can wrap at least a portion of the roll's circumference. In some embodiments, production tool 1350 wraps between 30 to 180 degrees, or between 90 to 180 degrees of the outer circumference of shaped abrasive particle transfer roll 1308. In some embodiments, the speed of the dispensing surface 1404 and the speed of the resin layer of resin coated backing 1314 are speed matched to each other within ⁇ 10 percent, ⁇ 5 percent, or ⁇ 1 percent, for example.
  • One method includes a pressure assist method where each cavity 1402 in production tooling 1350 has two open ends or the back surface or the entire production tooling 1350 is suitably porous and shaped abrasive particle transfer roll 1308 has a plurality of apertures and an internal pressurized source of air. With pressure assist, production tooling 1350 does not need to be inverted but it still may be inverted.
  • Shaped abrasive particle transfer roll 1308 can also have movable internal dividers such that the pressurized air can be supplied to a specific arc segment or circumference of the roll to blow shaped abrasive particles 1302 out of the cavities and onto resin coated backing 1314 at a specific location.
  • shaped abrasive particle transfer roll 1308 may also be provided with an internal source of vacuum without a corresponding pressurized region or in combination with the pressurized region typically prior to the pressurized region as shaped abrasive particle transfer roll 1308 rotates.
  • the vacuum source or region can have movable dividers to direct it to a specific region or arc segment of shaped abrasive particle transfer roll 1308.
  • the vacuum can suck shaped abrasive particles 1302 firmly into cavities 1402 as the production tooling 1350 wraps shaped abrasive particle transfer roll 1308 before subjecting shaped abrasive particles 1302 to the pressurized region of shaped abrasive particle transfer roll 1308.
  • This vacuum region be used, for example, with shaped abrasive particle removal member to remove excess shaped abrasive particles 1302 from dispensing surface 1404 or may be used to simply ensure shaped abrasive particles 1302 do not leave cavities 1402 before reaching a specific position along the outer circumference of the shaped abrasive particle transfer roll 1308.
  • production tooling 1350 travels along first web path 1304 back towards the shaped abrasive particle filling and excess removal section of the apparatus with the assistance of idler rolls 1310 as necessary.
  • An optional production tool cleaner can be provided to remove stuck shaped abrasive particles still residing in cavities 1402 and/or to remove make coat resin transferred to dispensing surface 1404. Choice of the production tool cleaner can depend on the configuration of the production tooling and could be either alone or in combination, an additional air blast, solvent or water spray, solvent or water bath, an ultrasonic horn, or an idler roll the production tooling wraps to use push assist to force shaped abrasive particles 1302 out of the cavities 1402. Thereafter production tooling 1350 or belt advances to a shaped abrasive particle filling and excess removal section to be filled with new shaped abrasive particles 1302.
  • Various idler rolls 1310 can be used to guide the shaped abrasive particle coated backing 1314 having a predetermined, reproducible, non-random pattern of shaped abrasive particles 1302 on the first major surface that were applied by shaped abrasive particle transfer roll 1308 and held onto the first major surface by the make coat resin along second web path 1306 into an oven for curing the make coat resin.
  • a second shaped abrasive particle coater can be provided to place additional abrasive particles, such as another type of abrasive particle or diluents, onto the make coat resin prior to entry in an oven.
  • the second abrasive particle coater can be a drop coater, spray coater, or an electrostatic coater as known to those of skill in the art Thereafter a cured backing with shaped abrasive particles 1302 can enter into an optional festoon along second web path 1306 prior to further processing such as the addition of a size coat, curing of the size coat, and other processing steps known to those of skill in the art of making coated abrasive articles.
  • system 1300 is shown as including production tool 1350 as a belt, it is possible in some alternative embodiments for system 1300 to include production tool 1350 on vacuum pull roll 1308.
  • vacuum pull roll 1308 may include a plurality of cavities 1402 to which shaped abrasive particles 1302 are directly fed. Shaped abrasive particles 1302 can be selectively held in place with a vacuum, which can be disengaged to release shaped abrasive particles 1302 on backing 1314. Further details on system 1300 and suitable alternative may be found at US 2016/0311081, to 3M Company, St Paul MN, the contents of which are hereby incorporated by reference.
  • the system 1300 described above may also be used to accurately place non-shaped particles. Due to the configuration of the production tool 1350 placement of particles is very specifically controlled, and may be used to form patterns of a first level, second level, and higher despite the particles themselves not having any pre-determined shape. In one example, a blend of shaped and non-shaped particles may also be used. In selected examples, relatively precise placement of non-shaped particles, using methods and equince described above may be used to form one or more patterns, in a similar manner to patterns formed through placement of shaped particles of the abrasive article, etc. It is recognized that the example abrasive articles described herein can include precisely-shaped particles, non- shaped particles or a combination thereof.
  • an abrasive article can include a linear pattern having particles arranged in staggered longitudinal rows or staggered lateral rows.
  • the staggered linear pattern is such that particles in adjacent rows can be laterally or longitudinally misaligned or staggered relative to one another, while particles in every other row can be aligned.
  • the staggered linear pattern can either be staggered in a longitudinal direction on the article or staggered in a lateral direction on the article.
  • Such design of abrasive articles having staggered rows of particles can be applicable to abrasive articles in the form of sheets, discs, belts, pads, or rolls.
  • the term“adjacent” refers to particles that are next to each other in different rows
  • the term “neighboring” or“neighbor” refers to particles that are next to each other in the same row.
  • Each particle can be described as having a unique lateral, longitudinal position on the abrasive article.
  • the figures described below include examples of an abrasive article in the form of a disc and a belt.
  • the article can be defined as having one or more longitudinal axes or longitudinal positions, which can be defined relative to a length of the article, and one or more lateral axes or lateral positions, which can be defined relative to a width of the article.
  • the disc in which the abrasive article is a disc, the disc can similarly be defined for purposes herein as having longitudinal positions that extend radially from a center point of the disc and lateral positions that can be formed by concentric circles formed around the center point of the disc. Concentric circles on the disc can have shared longitudinal positions that create longitudinal rows on the disc.
  • FIG. 6 shows an abrasive article 1500 in the form of a belt or sheet.
  • the belt 1500 can comprise a plurality of particles 1502, such as ceramic particles, attached to a backing substrate 1504.
  • the specified z-directian rotational orientation positions the substantially planar surface of the backing substrate 1504 at an angle of approximately 0 degrees to a longitudinal axis 1506 of the belt 1500.
  • each individual shaped abrasive particle is represented as a short line segment representative of the position of the base (sloping sidewall) of the shaped abrasive particle attached to the make coat.
  • the arrow indicates the direction of travel of the belt 1500 when placed onto a grinding tool.
  • the pattern created by the plurality of particles 1502 can comprise a plurality of parallel lines that can be described as longitudinal rows that are generally parallel to the longitudinal axis 1506. In addition to a longitudinal position on the substrate 1504, the particles 1502 can be described as having a lateral position on the substrate.
  • the particles 1502 are aligned laterally and longitudinally relative to one another. For example, as shown in FIG. 6, particle 1502A in a first row 1508 is in alignment with adjacent particle 1502A’ in a second row 1510; similarly, particle 1502B in the first row 1508 is in alignment with adjacent particle 1502B’ in the second row 1510. Neighboring particles 1502A and 1502B are in alignment relative to one another along a first longitudinal position, and neighboring particles 1502A’ and 1502B’ are in alignment relative to one another along a second longitudinal position.
  • FIG. 7 shows an abrasive article 1600 also in the form of a belt or sheet and comprising a plurality of particles 1602, such as ceramic particles, attached to a backing substrate 1604.
  • the specified z-direction rotational orientation positions the substantially planar surface of the backing substrate 1604 at an angle of approximately 0 degrees to a longitudinal axis 1606 of the belt 1600.
  • each individual shaped abrasive particle is represented as a short line segment representative of the position of the base (sloping sidewall) of the shaped abrasive particle attached to the make coat.
  • the arrow indicates the direction of travel of the belt 1600 when placed onto a grinding tool.
  • the belt 1600 can include a plurality of longitudinal rows that are generally parallel to the longitudinal axis 1606.
  • the plurality of longitudinal rows on the belt 1600 can be staggered such that particles 1602 in adjacent longitudinal rows can be laterally misaligned or staggered relative to one another.
  • the plurality of longitudinal rows can include a first row 1608, a second row 1610, a third row 1612, and a fourth row 1614.
  • the particles 1602 in the first row 1608 can be laterally aligned with particles 1602 in the third row 1612.
  • particles 1602 in the second row 1610 can be laterally aligned with particles 1602 in the fourth row 1614.
  • Particles 1602 in the second row 1610 and fourth row 1614 can be laterally staggered relative to particles in the first row 1608 and third row 1612.
  • Particle 1602A in the first row 1608 can be longitudinally aligned with neighboring particle 1602B in the first row 1608.
  • Particle 1602A can be laterally aligned with particle 1602A” in the third row 1612.
  • particle 1602B can be laterally aligned with particle 1602B” in the third row 1612.
  • Particle 1602A can be laterally mis-aligned or staggered relative to adjacent particle 1602A’ in the second row 1610.
  • Particle 1602B can be laterally mis aligned or staggered relative to adjacent particle 1602B’ in the second row 1610.
  • Particle 1602A’ can be referred to as adjacent to particle 1602A and adjacent to particle 1602B.
  • particle 1602B’ can be referred to as adjacent to particle 1602B and adjacent to particle 1602C.
  • Such pattern of rows 1608, 1610, 1612 and 1614 can repeat across at least a portion of the belt 1600.
  • the staggered linear pattern of FIG. 7 is described as staggering the longitudinal rows. It is recognized that the staggered linear pattern can include staggering the lateral rows such that every other lateral row is longitudinally aligned while adjacent lateral rows are longitudinally staggered.
  • FIG. 7 is not necessarily drawn to scale.
  • the particles 1602 may be more or less compact, relative to one another, than what is shown in FIG. 7.
  • the number of particles attached to the substrate 1604 may be more or less than what is shown in FIG. 7.
  • the longitudinal rows may include more or less particles 1602 than what is shown in FIG. 7.
  • a distance between neighboring particles (in the same longitudinal row) can be less than or greater than a distance between adjacent particles (in different rows). The spacing and distances between neighboring and adjacent particles is further described below in reference to FIGs. 10 and 11
  • the design of the particles having a staggered linear pattern on the article 1600 as shown in FIG. 7 may provide one or more advantages or benefits.
  • the staggered pattern may mask (or minimize to the eye of an individual looking at the abrasive article 1600) any unfilled or irregularly filled positions on the article 1600 where a particle was intended to be placed.
  • the staggered rows of particles may prevent a domino effect if one particle moves out of position (for example, the particle tips over from its upright position).
  • the staggered pattern may prevent such particle from also tipping over or otherwise disturbing an adjacent particle.
  • adjacent particles are aligned with one another, if one particle tips over or starts to tip, this can lead to multiple adjacent particles tipping one another over.
  • FIG. 8 shows a portion of an abrasive article 1700 in the form of a disc.
  • the disc 1700 can comprise a plurality of particles 1702, such as ceramic particles, attached to a backing substrate 1704.
  • the specified z-direction rotational orientation positions the substantially planar surface of the backing substrate 1704 circumferentially and a pattern created by the plurality of particles 1702 comprises a plurality of concentric circles.
  • the disc 1700 can be described for purposes herein as having longitudinal positions, which extend radially from a center point of the disc 1700, and lateral positions, which correspond to the concentric circles formed around the center point of the disc 1700.
  • each individual shaped abrasive particle is represented as a short line segment representative of the position of the base (sloping sidewall) of the shaped abrasive particle attached to the make coat.
  • the arrow indicates a direction of travel of the disc 1700 when placed onto a grinding tool.
  • the plurality of particles 1702 can be arranged on the disc 1700 such that at least a portion of the particles in the plurality of particles 1702 are aligned longitudinally and laterally relative to other particles 1702 on the disc 1700.
  • the placement of the particles 1702 along the concentric circles on the disc 1700 in a particular longitudinal position can create a longitudinal row of particles 1702 on the disc 1700.
  • the disc 1700 can include particles 1702 that are placed on the substrate 1704 in a pattern to form a first longitudinal row 1708, a second longitudinal row 1710, a first concentric circle 1720, and a second centric circle 1722.
  • the particles 1702 that form the first circle 1720 are arranged laterally relative to one another and the particles 1702 that form the second circle 1722 are arranged laterally relative to one another.
  • FIG. 9 shows a portion of an abrasive article 1800 in the form of a disc and comprising a plurality of particles 1802, such as ceramic particles, attached to a backing substrate 1804.
  • the specified z-direction rotational orientation positions the substantially planar surface of the backing substrate 1804 circumferentially.
  • a pattern created by the plurality of particles 1802 on the disc 1800 comprises a plurality of concentric circles, albeit a different number of concentric circles compared to the concentric circles on the disc 1700 (as described further below).
  • the disc 1800 can have a plurality of longitudinal positions, which extend radially from a center point of the disc 1800, and a plurality of lateral positions, which correspond to positions on the concentric circles formed around the center point of the disc 1800.
  • each individual shaped abrasive particle is represented as a short line segment representative of the position of the base (sloping sidewall) of the shaped abrasive particle attached to the make coat.
  • the arrow indicates a direction of travel of the disc 1800 when placed onto a grinding tool.
  • the disc 1800 can include a plurality of longitudinal positions or longitudinal rows on the disc 1800.
  • the plurality of longitudinal rows on the disc 1800 can be staggered such that particles 1802 in adjacent longitudinal rows can be laterally misaligned or staggered relative to one another.
  • the plurality of longitudinal rows can include a first row 1808, a second row 1810, a third row 1812, and a fourth row 1814.
  • the particles 1802 in the first row 1808 can be laterally aligned with particles in the third row 1812.
  • particles in the second row 1810 can be laterally aligned with particles in the fourth row 1814.
  • Particles 1802 in the second row 1810 and fourth row 1814 can be laterally staggered relative to particles 1802 in the first row 1808 and third row 1812.
  • Such pattern of rows 1808, 1810, 1812, and 1814 can repeat across at least a portion of the belt 1800.
  • the disc 1800 may have about twice as many concentric circles (formed by the particles 1802) as the disc 1700.
  • FIG. 9 illustrates concentric circles 1820 and 1822, which may be located on the disc 1800 in a similar lateral position to the concentric circles 1720 and 1722 of the disc 1700.
  • the disc 1800 can also include a concentric circle 1819 that is closer to the center point of the disc 1800 and a concentric circle 1821 positioned between the concentric circles 1820 and 1822.
  • the concentric circles 1819 and 1821 are created by the staggered particles 1802 in the second row 1810 and fourth row 1814.
  • the concentric circle 1821 can be positioned at an equidistance between the concentric circle 1820 and the concentric circle 1822.
  • a similar pattern of the circles 1819, 1820, 1821 and 1822 can repeat radially outward on the substrate 1804 from the center point of the disc 1800.
  • FIG. 9 shows longitudinal rows on the disc 1800 that are staggered such that particles 1802 in adjacent longitudinal rows can be laterally misaligned or staggered relative to one another.
  • lateral rows on the disc 1800 can instead be staggered such that adjacent lateral rows can be longitudinally misaligned or staggered relative to one another.
  • FIG. 9 is not necessarily drawn to scale.
  • the particles 1802 may be more or less compact, relative to one another, than what is shown in FIG. 9.
  • the number of particles attached to the substrate 1804 may be more or less than what is shown in FIG. 9.
  • the longitudinal rows on the substrate 1804 may include more or less particles 1802 than what is shown in FIG. 9.
  • a distance between neighboring particles 1802 (in the same longitudinal row) can be less than or greater than a distance between adjacent particles 1802 (in different rows). The spacing and distances between neighboring and adjacent particles is further described below in reference to FIGs. 10 and 11.
  • the design of the disc 1800 having a staggered linear pattern for placement of the particles on the backing substrate 1804 may provide at least the same advantages or benefits as described above in reference to the belt 1600 of FIG. 7. By creating staggered longitudinal rows on the disc 1800 (or staggered lateral rows), such staggered linear pattern may mask or decrease
  • the staggered linear pattern may minimize or eliminate the potential for tipping of multiple particles that can result from a domino effect after one particles moves out of its upright position.
  • abrasive articles having a staggered linear pattern can be formed by placing the particles in longitudinal rows on the article and staggering the longitudinal rows such that the particles are laterally misaligned relative to adjacent particles in the adjacent longitudinal row.
  • the particles can be arranged in a variety of configurations to accommodate a desired spacing between neighboring particles (in the same longitudinal rows) and a desired spacing between adjacent particles (in different longitudinal rows).
  • FIG. 10 is a schematic of a plurality of particles 1902 arranged in longitudinal and lateral rows.
  • the particles 1902 can be generally aligned longitudinally and laterally, assuming the particles 1902 are properly positioned on the backing substrate.
  • the particles 1902 can be similar to the particle 100 of FIGs. 1A and IB except that angle 108 of particles 1902 is about 90 degrees.
  • the particles 1902 are arranged lengthwise in a longitudinal direction, such that the length of the particle 1902 (see length L in FIG. 1A) is oriented generally along a longitudinal axis and the width of the particle 1902 (see width W in FIG. IB) is oriented generally along a lateral axis. It is recognized that in other examples the particles 1902 can be arranged lengthwise in a lateral direction.
  • a distance 1950 between neighboring particles 1902A and 1902B can be defined as a distance from a center point of particle 1902A to a center point of particle 1902B.
  • a distance 1952 between adjacent particles 1902B and 1902B’ can be defined as a distance from a center point of particle 1902B to a center point of particle 1902B’ .
  • the distance 1952 can be greater than, equal to or less than the distance 1950 depending on a spacing between neighboring particles and a spacing between adjacent particles.
  • the distance 1952 can be less than the distance 1950.
  • the distance 1952 can be less than half the distance 1950.
  • the center point of a particle refers to its center point relative to a width of the particle (shown in a lateral direction in FIG. 10) and relative to a length of the particle (shown in a longitudinal direction in FIG. 10).
  • FIG. 11 is a schematic of a plurality of particles 2002 arranged in a staggered linear pattern.
  • the particles 2002 can be similar to the particle 100 of FIGs. 1A and IB except that angle 108 of particles 2002 is about 90 degrees.
  • the particles 2002 are arranged lengthwise in a longitudinal direction, such that the length of the particle 2002 (see length L in FIG. 1 A) is oriented generally along a longitudinal axis and the width of the particle 2002 (see width W in FIG. IB) is oriented generally along a lateral axis. It is recognized that in other examples the particles 2002 can be arranged lengthwise in a lateral direction.
  • a plurality of longitudinal rows can include a first row 2008 and a second row 2010.
  • the pattern of the first row 2008 and second row 2010 can repeat as shown in FIG. 11.
  • Neighboring particles 2002A and 2002B in the first row 2008 can be separated by a distance 2050.
  • Neighboring particles 2002A’ and 2002B’ in the second row 2010 can be separated by a distance 2054.
  • the distances 2050 and 2054 can be generally equal.
  • the distance 2050 can be less than or greater than the distance 2054.
  • each particle 2002 in the second row 2010 can be placed at a lateral position that is equidistant to its two adjacent particles in the first row 2008.
  • the particle 2002B’in the second row 2010 can have a center point that is at a lateral position that corresponds to a lateral position in the first row 2008 that is at a mid-point between a top end of the particle 2002A and a bottom end of the particle 2002B.
  • a spacing between adjacent particles 2002B and 2002B’ can be defined as a diagonal distance 2056 between the center point of the particle 2002B and the center point of the particle 2002B’.
  • a spacing between adjacent particles 2002B and 2002C’ can be defined as a diagonal distance 2058 between the center point of the particle 2002B and a center point of the particle 2002C’.
  • the diagonal distances 2056 and 2058 can be equal.
  • the diagonal distances 2056 and 2058 can also be described relative to the distance between particles 2002B’ and 2002C’.
  • a distance 2060 can be defined as a lateral distance between neighboring particles 2002B’ and 2002C’ and specifically as the distance between the center point of particle 2002B’ and the center point of particle 2002C’ .
  • the distance 2060 can be the same measurement as the distance 2054 between the particle 2002A’ and the particle 2002B’.
  • the distance 2060 can be equal to the distances 2056 and 2058, in which case the three distances 2056, 2058 and 2060 can form a unilateral triangle.
  • the distance 2060 can be greater than one or both of the distances 2056 and 2058.
  • one or both of the distances 2056 and 2058 can be more than half of the distance 2060.
  • the distances 2056 and 2058 can be equal to one another. In other examples, the distances 2056 and 2058 can be different from one another, the spacing between adjacent particles in different rows can vary, or the spacing between neighboring particles in the same row can vary.
  • abrasive articles having a staggered linear pattern can include precisely- shaped particles, non-shaped particles, or a combination thereof.
  • the abrasive articles can include coated, shaped abrasive particles and at least a portion of the shaped abrasive articles can have a similar size and geometry.
  • the shaped abrasive particles can include triangular-shaped particles (described above in detail as an equilateral triangle conforming to a truncated pyramid), tetrahedral-shaped particles or a combination thereof.
  • the linear patterns described herein of longitudinal rows of particles with a staggered design can extend across some or all of the abrasive article.
  • substantially all of the particles on the abrasive article can be arranged in staggered rows.
  • some of the particles on the abrasive article can be arranged in staggered rows, while some of the particles can be laterally and longitudinally aligned or some of the particles can be randomly arranged on the backing substrate.
  • Example 1 provides an abrasive article comprising a backing substrate, a plurality of particles arranged laterally and longitudinally on the backing substrate, and an adhesive attaching the plurality of particles to the backing substrate. At least a portion of the particles of the plurality of particles can be arranged in a repeating pattern of a first longitudinal row and a second longitudinal row, the first longitudinal row comprising multiple particles arranged along a first longitudinal position on the article and neighboring particles in the first row are separated from one another by a first distance, the second row comprising multiple particles arranged along a second longitudinal position on the article, the second longitudinal position generally in parallel with the first longitudinal position, and neighboring particles in the second row are separated from one another by a second distance.
  • the particles in the second row can be laterally mis-aligned relative to the particles in the first row such that each of the particles in the second row has a different lateral position on the backing substrate compared to a lateral position of each of the particles in the first row.
  • Example 2 provides the abrasive article of Example 1 optionally configured wherein the plurality of particles comprises precisely-shaped particles.
  • Example 3 provides the abrasive article of Example 2 optionally configured wherein at least one of the precisely-shaped particles comprises a first side and a second side separated by a thickness t, the first side comprises a first face having a triangular perimeter and the second side comprises a second face having a triangular perimeter, wherein the thickness t is equal to or smaller than the length of the shortest side-related dimension of the particle.
  • Example 4 provides the abrasive article of Example 3 optionally further comprising at least one sidewall connecting the first side and the second side.
  • Example 5 provides the abrasive article of Example 4 optionally configured wherein the at least one sidewall is a sloping sidewall.
  • Example 6 provides the abrasive article of Example 2 optionally configured wherein at least one of the precisely-shaped particles is tetrahedral and comprises four faces joined by six edges terminating at four tips, each one of the four faces contacting three of the four faces.
  • Example 7 provides the abrasive article of Example 6 optionally configured wherein at least one of the four faces is substantially planar.
  • Example 8 provides the abrasive article of Example 6 or 7 optionally configured wherein at least one of the four faces is concave.
  • Example 9 provides the abrasive article of any one of Examples 6-8 optionally configured wherein at least one of the four faces is convex.
  • Example 10 provides the abrasive article of any one of Examples 1-9 optionally configured wherein a z-direction rotational angle about a line perpendicular to a major surface of the backing substrate and passing through individual particles of the plurality of particles is substantially the same for a portion of the plurality of particles.
  • Example 11 provides the abrasive article of any one of Examples 1-10 optionally configured wherein the particles are formed of a ceramic material.
  • Example 12 provides the abrasive article of any one of Examples 1-11 optionally configured wherein the particles are formed of a polymeric material.
  • Example 13 provides the abrasive article of any one of Examples 1-12 optionally configured wherein the backing substrate is a disc.
  • Example 14 provides the abrasive article of Example 13 optionally configured wherein at least a portion of the particles of the plurality of particles are arranged to form a plurality of concentric circles.
  • Example 15 provides the abrasive article of Example 14 optionally configured wherein particles from a first circle among the plurality of concentric circles have a shared longitudinal position with particles from other circles among the plurality of concentric circles, and the shared longitudinal positions create the first and second longitudinal rows on the disc.
  • Example 16 provides the abrasive article of any one of Examples 1-12 optionally configured wherein the backing substrate is a belt.
  • Example 17 provides the abrasive article of Example 16 optionally configured wherein the first and second longitudinal positions are first and second longitudinal axes of the article.
  • Example 18 provides the abrasive article of any one of Examples 1-17 optionally configured wherein the first distance is defined as a space between a center point of a first particle in the first row and a center point of a second particle in the first row, and the second particle is a neighbor of the first particle, and wherein the second distance is defined as a space between a center point of a third particle in the second row and a center point of a fourth particle in the second row, and the third particle is a neighbor of the fourth particle.
  • Example 19 provides the abrasive article of any one of Examples 1-18 optionally configured wherein the second distance is equal to the first distance.
  • Example 20 provides the abrasive article of any one of Examples 1-18 optionally configured wherein the second distance is different than the first distance.
  • Example 21 provides the abrasive article of any one of Examples 1-20 optionally configured wherein a third distance is defined as a space between adjacent particles in the first row and the second row, the third distance measured as a diagonal distance between a center point of a first particle in the first row and a center point of a second particle in the second row.
  • Example 22 provides the abrasive article of Example 21 optionally configured wherein the third distance is less than at least one of the first distance and the second distance.
  • Example 23 provides the abrasive article of Example 21 optionally configured wherein the third distance is at least half the length of the first distance or the second distance.
  • Example 24 provides the abrasive article of Example 21 optionally configured wherein the third distance is generally equal to at least one of the first distance and the second distance.
  • Example 25 provides a coated abrasive article comprising a flexible backing substrate, a plurality of particles attached to the flexible backing substrate, and a curable adhesive for attaching the particles to the flexible backing substrate. At least a portion of the particles in the plurality of particles can have similar geometry relative to one another and each of the particles has a lateral position and a longitudinal position on the flexible backing substrate.
  • At least a portion of the particles of the plurality of particles can be arranged on the flexible backing substrate in a plurality of rows, each row is created by attaching multiple particles in alignment along a first longitudinal position on the article to create neighboring particles, the neighboring particles in each row are separated from one another by a first distance, and the plurality of particles comprises a first row, a second row adjacent to the first row, and a third row adjacent to the second row.
  • the rows of particles can be staggered relative to one another such that particles in the first row are laterally aligned with particles in the third row and particles in the second row are laterally staggered relative to particles in the first and third rows.
  • Each particle in the second row can be positioned laterally in a space equidistant between neighboring particles in each of the first and third rows.
  • Example 26 provides the abrasive article of Example 25 optionally configured wherein the plurality of particles further comprises a fourth row adjacent to the third row, and the particles in the fourth row are aligned laterally with particles in the second row.
  • Example 27 provides the abrasive article of Example 26 optionally configured wherein the first, second, third and fourth rows of particles repeat across at least a portion of the flexible backing substrate.
  • Example 28 provides the abrasive article of any one of Examples 25-27 optionally configured wherein the particles are formed of a ceramic material.
  • Example 29 provides the abrasive article of any one of Examples 25-28 optionally configured wherein the particles are formed of a polymeric material.
  • Example 30 provides the abrasive article of any one of Examples 25-29 optionally configured wherein at least a portion of the particles in the plurality of particles are precisely- shaped particles.
  • Example 31 provides the abrasive article of Example 30 optionally configured wherein at least one of the precisely-shaped particles comprises a first side and a second side separated by a thickness t, the first side comprises a first face having a triangular perimeter and the second side comprises a second face having a triangular perimeter, wherein the thickness t is equal to or smaller than the length of the shortest side-related dimension of the particle.
  • Example 32 provides the abrasive article of Example 30 optionally configured wherein at least one of the precisely-shaped particles is tetrahedral and comprises four faces joined by six edges terminating at four tips, each one of the four faces contacting three of the four faces.
  • Example 33 provides the abrasive article of any one of Examples 25-32 optionally configured wherein the flexible backing substrate is a disc.
  • Example 34 provides the abrasive article of any one of Examples 25-32 optionally configured wherein the flexible backing substrate is a belt.
  • Example 35 provides the abrasive article of any one of Examples 25-34 optionally configured wherein the first distance is defined relative to a distance from a center point of a first particle in the first row to a center point of a second particle in the first row, and the second particle is a neighbor of the first particle.
  • Example 36 provides the abrasive article of any one of Examples 25-35 optionally configured wherein a second distance is a space between adjacent particles in the first row and the second row, and the second distance is a diagonal distance from a center point of a first particle in the first row to a center point of a second particle in the second row.
  • Example 37 provides a method of forming an abrasive article, the method comprising: aligning a plurality of particles into a pattern, wherein the pattern includes particles positioned laterally and longitudinally to form a plurality of longitudinal rows, transferring the pattern to a backing substrate containing a layer of adhesive, and curing the adhesive.
  • the plurality of longitudinal rows can be arranged in a repeating pattern of a first longitudinal row and a second longitudinal row, the first longitudinal row comprising multiple particles arranged along a first longitudinal position on the article and neighboring particles in the first row are separated from one another by a first distance.
  • the second row can comprise multiple particles arranged along a second longitudinal position on the article, the second longitudinal position is generally parallel to the first longitudinal position, and neighboring particles in the second row are separated from one another by a second distance.
  • the particles in the second row can be laterally mis-aligned relative to the particles in the first row such that each of the particles in the second row has a different lateral position on the backing substrate compared to a lateral position of each of the particles in the first row.
  • Example 38 provides the method of Example 37 optionally configured wherein aligning the plurality of particles into a pattern includes spacing neighboring particles of a respective row at a greater distance than spacing between adjacent particles in the first and second rows.
  • Example 39 provides the method of Example 37 or 38 optionally configured wherein aligning the plurality of particles into a pattern includes collecting the plurality of particles into pockets formed in a tooling surface.
  • Example 40 provides an article or method of any one or any combination of Examples 1- 39, which can be optionally configured such that all steps or elements recited are available to use or select from.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Polishing Bodies And Polishing Tools (AREA)

Abstract

L'invention concerne des articles abrasifs et des procédés associés qui comprennent des particules abrasives agencées selon un motif sur au moins une partie d'un substrat de support de l'article. Le motif peut comprendre une pluralité de rangées longitudinales qui se répètent sur au moins une partie de l'article abrasif, et les rangées longitudinales peuvent être en quinconce les unes par rapport aux autres de telle sorte que les particules dans chaque autre rangée soient alignées latéralement les unes par rapport aux autres, mais que les particules dans des rangées adjacentes soient décalées latéralement ou en quinconce les unes par rapport aux autres. Dans un autre exemple, le motif peut comprendre une pluralité de rangées latérales dans lesquelles des particules dans chaque autre rangée latérale sont alignées longitudinalement mais des particules dans des rangées latérales adjacentes sont décalées longitudinalement ou en quinconce. Une telle conception ayant des rangées en quinconce de particules peut être applicable à des articles abrasifs se présentant sous la forme de feuilles, de disques, de courroies, de tampons ou de rouleaux.
PCT/IB2019/060953 2018-12-18 2019-12-17 Motif linéaire en quinconce pour articles abrasifs WO2020128857A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US201862780987P 2018-12-18 2018-12-18
US62/780,987 2018-12-18

Publications (1)

Publication Number Publication Date
WO2020128857A1 true WO2020128857A1 (fr) 2020-06-25

Family

ID=69159855

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IB2019/060953 WO2020128857A1 (fr) 2018-12-18 2019-12-17 Motif linéaire en quinconce pour articles abrasifs

Country Status (1)

Country Link
WO (1) WO2020128857A1 (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11911876B2 (en) 2018-12-18 2024-02-27 3M Innovative Properties Company Tooling splice accommodation for abrasive article production
US11992918B2 (en) 2018-12-18 2024-05-28 3M Innovative Properties Company Abrasive article maker with differential tooling speed
US12011807B2 (en) 2018-12-18 2024-06-18 3M Innovative Properties Company Shaped abrasive particle transfer assembly
US12017327B2 (en) 2018-12-18 2024-06-25 3M Innovative Properties Company Particle reception in abrasive article creation

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2012112305A2 (fr) * 2011-02-16 2012-08-23 3M Innovative Properties Company Article abrasif revêtu ayant des particules abrasives céramiques façonnées alignées en rotation et procédé de fabrication
US20150291866A1 (en) * 2014-04-14 2015-10-15 Saint-Gobain Ceramics & Plastics, Inc. Abrasive article including shaped abrasive particles
US9457453B2 (en) * 2013-03-29 2016-10-04 Saint-Gobain Abrasives, Inc./Saint-Gobain Abrasifs Abrasive particles having particular shapes and methods of forming such particles
US20160311081A1 (en) 2013-12-23 2016-10-27 3M Innovative Properties Company A coated abrasive article maker apparatus

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2012112305A2 (fr) * 2011-02-16 2012-08-23 3M Innovative Properties Company Article abrasif revêtu ayant des particules abrasives céramiques façonnées alignées en rotation et procédé de fabrication
US9457453B2 (en) * 2013-03-29 2016-10-04 Saint-Gobain Abrasives, Inc./Saint-Gobain Abrasifs Abrasive particles having particular shapes and methods of forming such particles
US20160311081A1 (en) 2013-12-23 2016-10-27 3M Innovative Properties Company A coated abrasive article maker apparatus
US20150291866A1 (en) * 2014-04-14 2015-10-15 Saint-Gobain Ceramics & Plastics, Inc. Abrasive article including shaped abrasive particles

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11911876B2 (en) 2018-12-18 2024-02-27 3M Innovative Properties Company Tooling splice accommodation for abrasive article production
US11992918B2 (en) 2018-12-18 2024-05-28 3M Innovative Properties Company Abrasive article maker with differential tooling speed
US12011807B2 (en) 2018-12-18 2024-06-18 3M Innovative Properties Company Shaped abrasive particle transfer assembly
US12017327B2 (en) 2018-12-18 2024-06-25 3M Innovative Properties Company Particle reception in abrasive article creation

Similar Documents

Publication Publication Date Title
US12011807B2 (en) Shaped abrasive particle transfer assembly
WO2020128844A1 (fr) Macro-motif pour articles abrasifs
US20220055182A1 (en) Multiple orientation cavities in tooling for abrasives
US20220040814A1 (en) Patterned abrasive substrate and method
KR102469608B1 (ko) 미세입자 코팅된 연마 그레인을 갖는 연마 물품
WO2020128717A1 (fr) Substrat abrasif à motifs et procédé
US11992918B2 (en) Abrasive article maker with differential tooling speed
CN113226650B (zh) 带有锯齿的成形磨料颗粒及其制造方法
US20220055185A1 (en) Coated abrasive article having spacer particles, making method and apparatus therefor
US20220056327A1 (en) Bonded abrasive article precursor
WO2020128857A1 (fr) Motif linéaire en quinconce pour articles abrasifs
US20220033699A1 (en) Self-orienting shaped abrasive particles
US20220063061A1 (en) Camouflage for abrasive articles
US20220048162A1 (en) Backfill to secure orientation for abrasive structure
US20230332029A1 (en) Abrasive particles
EP4323149A1 (fr) Structures linéaires de particules abrasives alignées

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 19835794

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 19835794

Country of ref document: EP

Kind code of ref document: A1