Patent Description:
<CIT> forms the basis for the preamble of claim <NUM>.

In various embodiments, the present invention provides a nonwoven abrasive article including a nonwoven web including fibers and pores between the fibers. The nonwoven abrasive article includes abrasive particles, wherein each of the pores between the fibers independently includes one or more of the abrasive particles. Each pore is independently about the same size as the one or more abrasive particles therein.

In various embodiments, the present invention provides a nonwoven abrasive article including a nonwoven web including fibers and pores between the fibers. The fibers in the nonwoven web including first fibers having a first diameter and second fibers having a second diameter. The nonwoven abrasive particle includes abrasive particles, wherein at least a portion of the pores between the fibers independently includes one or more of the abrasive particles. The first fibers have a denier of about <NUM>. The second fiber have a denier of about <NUM>. The first fibers are about <NUM> wt% of the fibers in the nonwoven web. The second fibers are about <NUM> wt% of the fibers in the nonwoven web.

In various embodiments, the present invention provides a nonwoven abrasive article including fibers and pores between the fibers. The nonwoven abrasive article includes abrasive particles, wherein at least a portion of the pores between the fibers independently includes one or more of the abrasive particles. Each of the pores is independently about the same size as the one or more abrasive particles therein. A <NUM>-inch (<NUM>-cm) diameter <NUM>-inch (<NUM>-cm) width test wheel having the same composition as the nonwoven abrasive article tested on <NUM>/<NUM>-inch (<NUM>-cm) diameter carbon steel over <NUM> minutes, using <NUM> pounds (<NUM>) of force, at <NUM> rotations per minute, <NUM> seconds on and <NUM> seconds off, has a wear of about <NUM> to about <NUM> of the test wheel. A <NUM>-inch (<NUM>-cm) diameter <NUM>-inch (<NUM>-cm) width test wheel having the same composition as the nonwoven abrasive article tested on <NUM>/<NUM>-inch (<NUM>-cm) diameter carbon steel over <NUM> minutes, using <NUM> pounds (<NUM>) of force, at <NUM> rotations per minute, <NUM> seconds on and <NUM> seconds off, has a cut of the carbon steel of about <NUM> to about <NUM>. The nonwoven abrasive article has a density of about <NUM>/ in<NUM> to about <NUM>/ in<NUM>.

In various embodiments, the present invention provides a method of forming the nonwoven abrasive article. The method includes forming a prebond including a resin and the fibers. The method includes coating the abrasive particles onto the prebond. The method includes compressing the coated prebond. The method includes curing the compressed prebond, to provide the nonwoven abrasive article.

In various embodiments, the present invention provides a method of using the nonwoven abrasive article. The method includes abrading a substrate with the nonwoven abrasive article.

In various embodiments, the present nonwoven abrasive article has certain advantages over other nonwoven abrasive articles, at least some of which are unexpected. For example, in various embodiments, the nonwoven abrasive article of the present invention can have a better wear rate than other nonwoven abrasive articles. In various embodiments, the nonwoven abrasive article of the present invention can have a better cut rate than other nonwoven abrasive articles.

Some nonwoven abrasive articles including abrasive particles, such as shaped abrasive particles, can have high cut rates combined with high wear rates. For example, substituting shaped abrasive particles for crushed abrasive particles in nonwoven abrasive articles can result in increased cut rate but the same wear rate or an increased wear rate. In various embodiments, the present invention provides a nonwoven abrasive article including abrasive particles, such as shaped abrasive particles, having a high cut rate combined with a lower wear rate than other abrasive articles having a similar cut rate.

Reference will now be made in detail to certain embodiments of the disclosed subject matter, examples of which are illustrated in part in the accompanying drawings. While the disclosed subject matter will be described in conjunction with the enumerated claims, it will be understood that the exemplified subject matter is not intended to limit the claims to the disclosed subject matter.

Throughout this document, 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. For example, a range of "about <NUM>% to about <NUM>%" or "about <NUM>% to <NUM>%" should be interpreted to include not just about <NUM>% to about <NUM>%, but also the individual values (e.g., <NUM>%, <NUM>%, <NUM>%, and <NUM>%) and the sub-ranges (e.g., <NUM>% to <NUM>%, <NUM>% to <NUM>%, <NUM>% to <NUM>%) within the indicated range. The statement "about X to Y" has the same meaning as "about X to about Y," unless indicated otherwise. Likewise, the statement "about X, Y, or about Z" has the same meaning as "about X, about Y, or about Z," unless indicated otherwise.

In this document, the terms "a," "an," or "the" are used to include one or more than one unless the context clearly dictates otherwise. The term "or" is used to refer to a nonexclusive "or" unless otherwise indicated. The statement "at least one of A and B" has the same meaning as "A, B, or A and B. " In addition, it is to be understood that the phraseology or terminology employed herein, and not otherwise defined, is for the purpose of description only and not of limitation. Any use of section headings is intended to aid reading of the document and is not to be interpreted as limiting; information that is relevant to a section heading may occur within or outside of that particular section.

In the methods described herein, the acts can be carried out in any order without departing from the principles of the invention, 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.

The term "about" as used herein can allow for a degree of variability in a value or range, for example, within <NUM>%, within <NUM>%, or within <NUM>% of a stated value or of a stated limit of a range, and includes the exact stated value or range.

The term "substantially" as used herein refers to a majority of, or mostly, as in at least about <NUM>%, <NUM>%, <NUM>%, <NUM>%, <NUM>%, <NUM>%, <NUM>%, <NUM>%, <NUM>%, <NUM>%, <NUM>%, <NUM>%, <NUM>%, or at least about <NUM>% or more, or <NUM>%.

In various embodiments, the present invention provides a nonwoven abrasive article. The nonwoven abrasive article includes a nonwoven web including fibers. The nonwoven web can include pores between the fibers. The nonwoven abrasive article includes abrasive particles. In one embodiment, at least a portion of the pores between the fibers can independently include one or more of the abrasive particles. Each pore can independently be about the same size as the one or more abrasive particles therein.

The nonwoven abrasive article can further include a binder. The binder can adhere the abrasive particles to the fibers of the nonwoven web. The binder can be any suitable binder. The binder can be a thermoplastic or thermoset material. The binder can be a phenolic resin, a urethane resin, hide glue, an acrylic resin, a urea-formaldehyde resin, a melamineformaldehyde resin, an epoxy resin, or a combination thereof. Urethane resins can include materials curable to form a poly(urea-urethane), such as polyurethanes having isocyanate functionality thereon curable with amine-containing materials.

The nonwoven abrasive article can include one compressed layer of the nonwoven web having abrasive particles therein, or can include two or more compressed and bonded layers of the nonwoven web having abrasive particles therein. For example, the nonwoven abrasive article can include <NUM>-<NUM>, <NUM>-<NUM>, <NUM>, or less than, equal to, or greater than <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or about <NUM> compressed and bonded layers of the nonwoven web having abrasive particles therein. The nonwoven abrasive article can be a unitized abrasive wheel designed to abrade a substrate contacted to the outer perimeter of the wheel when the wheel is turned around a hole in its center (e.g., an arbor hole), such as by using a suitable grinding or cutting machine.

The nonwoven abrasive article can have any suitable wear rate. In various embodiments, the nonwoven abrasive article can have a lower wear rate than other nonwoven abrasive articles having a similar cut rate. In some embodiments, a <NUM>-inch (<NUM>-cm) diameter <NUM>-inch (<NUM>-cm) width test wheel having the same composition as the nonwoven abrasive article tested on <NUM>/<NUM>-inch diameter carbon steel over <NUM> minutes, using <NUM> pounds (<NUM>) of force, at <NUM> rotations per minute, <NUM> seconds on and <NUM> seconds off, has a wear of about <NUM> to about <NUM> of the test wheel, or about <NUM> to about <NUM> of the test wheel, or about <NUM> or less, or less than, equal to, or greater than about <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or about <NUM> or more.

The nonwoven abrasive article can have any suitable cut rate. In various embodiments a <NUM>-inch (<NUM>-cm) diameter <NUM>-inch (<NUM>-cm) width test wheel having the same composition as the nonwoven abrasive article tested on <NUM>/<NUM>-inch (<NUM>-cm) diameter carbon steel over <NUM> minutes, using <NUM> pounds (<NUM>) of force, at <NUM> rotations per minute, <NUM> seconds on and <NUM> seconds off, cuts about <NUM> to about <NUM> of the carbon steel, or about <NUM> to about <NUM>, or about <NUM> to about <NUM>, or about <NUM> to about <NUM>, or about <NUM> or less, or less than, equal to, or greater than about <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or about <NUM> or more.

The nonwoven abrasive article can have any suitable density, such as a density of at least about <NUM>/ in<NUM> to no greater than about <NUM>/ in<NUM>, or at least about <NUM>/ in<NUM> to no greater than about <NUM>/ in<NUM>, or about <NUM>/ in<NUM> or less, or less than, equal to, or greater than about <NUM>/ in<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> or <NUM>/ in<NUM>.

The nonwoven abrasive article includes abrasive particles. The abrasive particles can be any suitable abrasive particles. The abrasive particles can be irregularly shaped (e.g., crushed or ground particles) or shaped particles.

The abrasive particles can be formed from any suitable material. For example, the abrasive particles can include fused aluminum oxide based materials such as aluminum oxide, ceramic aluminum oxide (which may 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. The abrasive particles may be in the form of, for example, individual particles, agglomerates, composite particles, and mixtures thereof.

The abrasive particles can be irregularly shaped. For example, the abrasive particles can be obtained by a crushing, grinding, or comminution process that produces abrasive particles of random size and shape. The particles can then be screened to give particles having a particular size range.

The abrasive particles can be shaped abrasive particles. A shaped abrasive particle means an abrasive particle having at least a partially replicated shape. One process to make a shaped abrasive particle includes shaping the precursor ceramic abrasive particle in a mold having a predetermined shape to make shaped abrasive particles. Shaped abrasive particles, formed in a mold, are one species in the genus of shaped abrasive particles. Other processes to make other species of shaped abrasive particles include extruding the precursor abrasive particle through an orifice having a predetermined shape, printing the precursor shaped abrasive particle though an opening in a printing screen having a predetermined shape, or embossing the precursor shaped abrasive particle into a predetermined shape or pattern. Non-limiting examples of shaped abrasive particles include triangular plates as disclosed in <CIT>; <CIT>;<CIT>; <CIT>; <CIT>;<CIT>; <CIT>; and<CIT>; and in in <CIT>, <CIT>, and <CIT>; or elongated ceramic rods/filaments often having a circular cross section produced by Saint-Gobain Abrasives an example of which is disclosed in <CIT>. Shaped 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 can bonds smaller abrasive particles into an agglomerated structure. Shaped abrasive particles can exclude particles that can be obtained by a crushing, grinding, or comminution process that produces abrasive particles of random size and shape. The shaped abrasive particles can have any suitable shape. The shaped abrasive particles can include a perimeter that is polygonal, and can include sides that are substantially flat. The shaped abrasive particle can include a perimeter that is triangular (e.g., equatorial, isosceles), rectangular, circular, elliptical, trapezoidal, pentagonal, star-shaped, or a combination thereof.

The abrasive particles can have any suitable particle size (e.g., largest dimension). In various embodiments, the abrasive particle can have a particle size of about <NUM> microns to about <NUM>,<NUM> microns, or about <NUM> microns to about <NUM> microns, or about <NUM> microns to about <NUM> microns, or about <NUM> microns or less, or less than, equal to, or greater than about <NUM> microns, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>,<NUM>, <NUM>,<NUM>, or about <NUM>,<NUM> microns or greater.

The nonwoven abrasive article includes a nonwoven web including fibers. The fibers can be made of any suitable material. For example, the fibers can be natural fibers, synthetic fibers, or mixtures of natural and synthetic fibers. Examples of synthetic fibers can include polyester, nylon, polypropylene, acrylonitrile, rayon, cellulose acetate, polyvinylidene chloride-vinyl chloride copolymers, vinyl chloride-acrylonitrile copolymers, or combinations thereof. Examples of suitable natural fibers include cotton, wool, jute, and hemp. The fiber may be of virgin material or of recycled or waste material, for example, reclaimed from garment cuttings, carpet manufacturing, fiber manufacturing, or textile processing. The fiber can be homogenous or a composite such as a bicomponent fiber (e.g., a co-spun sheath-core fiber). The fibers can be continuous filaments such as those formed by an extrusion process.

The fibers can have any suitable shape. The fibers can have a circular cross-section. In some embodiments, the fibers can have a non-circular cross sectional shape or can be a blends of fibers having a circular and a non-circular cross sectional shape. Non-circular cross sectional shapes can include triangular, delta, H-shaped, trilobal, rectangular, square, dog-bone, ribbon-shaped, and oval. The diameter of a fiber having a non-circular cross section is the largest dimension of the non-circular cross-section of the fiber. The fibers can have a substantially uniform diameter, wherein the largest dimension of the cross section of each fiber is substantially the same from one end of the fiber to the other.

The fibers in the nonwoven web can have a single diameter (e.g., a single uniform diameter). The nonwoven web can be substantially free of fibers have a different diameter than the single diameter. The single diameter can be about <NUM> denier (e.g., grams per <NUM>,<NUM> meters) to about <NUM>,<NUM> denier, or about <NUM> denier to about <NUM> denier, or about <NUM> denier or less, or less than, equal to, or greater than about <NUM> denier, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or about <NUM>,<NUM> denier or more.

In some embodiments, the fibers in the nonwoven web can have more than one diameter. For example, the fibers in the nonwoven web can include first fibers having a first diameter (e.g., a first uniform diameter), and second fibers having a second diameter (e.g., second uniform diameter), wherein the first diameter is different than the second diameter. In various embodiments, the fibers in the nonwoven web can include any suitable number of diameters, such as further including third fibers having a third diameter, fourth fibers having a fourth diameter, and the like.

In a nonwoven web including first fibers and second fibers, the first fibers can form any suitable proportion of the fibers in the nonwoven web. For example, the first fibers can be about <NUM> wt% to about <NUM> wt% of the fibers in the nonwoven web, or about <NUM> wt% to about <NUM> wt%, or about <NUM> wt% to about <NUM> wt%, or about <NUM> wt% or less, or less than, equal to, or greater than about <NUM> wt%, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> wt%, or about <NUM> wt% or more of the fibers in the nonwoven web. The first fibers can be about <NUM> denier to about <NUM>,<NUM> denier, or about <NUM> denier to about <NUM> denier, or about <NUM> denier or less, or less than, equal to, or greater than about <NUM> denier, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or about <NUM>,<NUM> denier or more. The first fibers can be about <NUM> denier.

In a nonwoven web including first fibers and second fibers, the second fibers can form any suitable proportion of the fibers in the nonwoven web. For example, the second fibers can be about <NUM> wt% to about <NUM> wt% of the fibers in the nonwoven web, or about <NUM> wt% to about <NUM> wt%, or about <NUM> wt% to about <NUM> wt%, or about <NUM> wt% or less, or less than, equal to, or greater than about <NUM> wt%, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> wt%, or about <NUM> wt% or more of the fibers in the nonwoven web. The second fibers can be about <NUM> denier to about <NUM>,<NUM> denier, or about <NUM> denier to about <NUM> denier, or about <NUM> denier or less, or less than, equal to, or greater than about <NUM> denier, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or about <NUM>,<NUM> denier or more. The second fibers can be about <NUM> denier, or about <NUM> denier.

In a nonwoven web including first fibers and second fibers, the first fibers can have a smaller diameter than the second fibers. For example, the first fibers can have a denier that is about <NUM> denier to about <NUM> denier less than the second fibers, or about <NUM> denier to about <NUM> denier less than the second fibers, or about <NUM> denier or less, or less than, equal to, or greater than about <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or about <NUM> denier or more.

In some embodiments, the nonwoven web includes first fibers having a denier or about <NUM> that are about <NUM> wt% of the fibers in the nonwoven web, and second fibers having a denier of about <NUM> that are about <NUM> wt% of the fibers in the nonwoven web. In some embodiments, the nonwoven web can be substantially free of fibers other than the first fibers and second fibers.

The fibers of the nonwoven web include pores that are spaces in-between groups of fibers. The fibers forming a pore can be characterized as a cage around the pore, wherein the fibers forming the pore do not seal the pore off from the surrounding environment. Some or each of the pores between the fibers can independently include one or more of the abrasive particles, such that the one or more abrasive particles in the pore are in the interior of the cage formed by the fibers that form the pore. Each pore can independently be about the same size as the one or more abrasive particles therein. In addition to the pores that include abrasive particles, the nonwoven web can also include pores that are free of abrasive particles.

A pore can include one abrasive particle, or more than one abrasive particle. In some embodiments, the pores of the nonwoven abrasive article can include not more than one of the abrasive particles (e.g., the pore can include zero or one particle). In some embodiments, the pores of the nonwoven abrasive article can include not more than one of the abrasive particles and can be free of other abrasive particles. In some embodiments, the nonwoven abrasive article can include secondary pores between the fibers. In some embodiments, the secondary pores can be pores of the same or smaller size than the other pores. The secondary pores between the fibers can be free of abrasive particles.

In various embodiments, the one or more abrasive particles in each pore can independently have a volume that is any suitable proportion of the volume of the pore, wherein the volume of the pore can be considered to be the maximum volume of any shape that does not protrude from the boundary of the pore that the pore can accommodate. The one or more abrasive particles in each pore can independently have a volume that is about <NUM>% to about <NUM>% of the volume of the pore, or about <NUM>% to about <NUM>% of the volume of the pore, or about <NUM>% or less, or less than, equal to, or greater than about <NUM>%, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or about <NUM>% or more of the volume of the pore. In various embodiments, any suitable proportion of the total number of pores in the nonwoven abrasive article having a volume that is larger than the abrasive particle can include one or more abrasive particles, such as about <NUM>% to about <NUM>%, or about <NUM>% to about <NUM>%, or about <NUM>% to about <NUM>%, or about <NUM>% or less, or less than, equal to, or greater than about <NUM>%, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or <NUM>% or more.

The pores can be substantially conformed to the one or more abrasive particles therein. The abrasive particles can include one or more substantially flat faces (e.g., the abrasive particles can be shaped abrasive particles or can be randomly shaped particles including one or more substantially flat faces). The substantially flat face of the abrasive particle can be contacted by (e.g., directly contacted by or separated by binder that is less than <NUM> fiber diameters thick) one or more of the fibers of the nonwoven web that are substantially parallel to the flat face, such that the contacting fibers is flush and adjacent to the substantially flat face. Any suitable proportion of the surface area of substantially flat faces of the abrasive particle can be contacted by one or more of the parallel fibers (e.g., wherein the percentage given represents the percentage of the total surface area of all the flat faces contacted per particle), such as about <NUM>% to about <NUM>%, or about <NUM>% to about <NUM>%, or about <NUM>% or less, or about <NUM>%, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, or about <NUM>%.

The nonwoven abrasive article can include any suitable component. The nonwoven abrasive article can include or can be free of any material listed in this section.

The nonwoven abrasive article can include a surfactant, an emulsifier, a dispersant, a crosslinking agent, a catalyst, a rheology modifier, a density modifier, a cure modifier, a free radical initiator, a diluent, an antioxidant, a heat stabilizer, a flame retardant, a plasticizer, filler, an inorganic particle, a pigment, a dye, an adhesion promoter, antistatic additives, or a combination thereof.

In some embodiments, the nonwoven abrasive article can include filler particles. For example, the filler particles can be blended with the shaped abrasive particles. Examples of useful fillers for this invention can 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, aluminum trihydrate, 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), polysulfone, polystyrene, acrylonitrile-butadiene-styrene block copolymer, polypropylene, acetal polymers, polyurethanes, nylon particles) and thermosetting particles (such as phenolic bubbles, phenolic beads, polyurethane foam particles and the like). The filler may also be a salt such as a halide salt. Examples of halide salts include sodium chloride, potassium cryolite, sodium cryolite, ammonium cryolite, potassium tetrafluoroborate, sodium tetrafluoroborate, silicon fluorides, potassium chloride, and magnesium chloride. Examples of metal fillers include, tin, lead, bismuth, cobalt, antimony, cadmium, iron and titanium. Other fillers can include sulfur, organic sulfur compounds, graphite, lithium stearate, and metallic sulfides.

Various embodiments of the present invention provide a method of making the nonwoven abrasive article. The method can be any suitable method that generates an embodiment of the nonwoven abrasive article described herein.

The method can include forming a prebond including resin, fibers, and abrasive particles. The method can include compressing multiple prebonds together, followed by curing the compressed prebonds, to form the nonwoven abrasive article.

In some embodiments, the method can include forming a prebond that includes resin and fibers. The method can include coating abrasive particles onto the prebond. The method can include compressing the coated prebond. The method can include curing the compressed prebond, to provide the nonwoven abrasive article.

In various embodiments, the present invention provides a method of using the nonwoven abrasive article. The method can be any suitable method of using an embodiment of the nonwoven abrasive article described herein. The method can include abrading a substrate with an embodiment of the nonwoven abrasive article described herein.

Various embodiments of the present invention can be better understood by reference to the following Examples which are offered by way of illustration. The present invention is not limited to the Examples given herein.

Materials used in the Examples are described in Table <NUM>. Unless stated otherwise, all other reagents were obtained, or are available from fine chemical vendors such as Sigma-Aldrich Company, St. Louis, Missouri, or may be synthesized by known methods.

Preparation of prebonds. A nonwoven web was formed on an air laid fiber web forming machine, available under the trade designation "RANDO-WEBBER" from the Rando Machine Corporation of Macedon, New York. The fiber web was formed from fiber blends shown in Table <NUM>. The weight of the web was approximately <NUM> grams per square meter (gsm). The web was conveyed to a horizontal, two-roll coater, where a prebond resin was applied at a wet add-on weight of <NUM> gsm. The prebond resin had the following composition (all percentages relative to component weight): <NUM>% water, <NUM>% T403S, <NUM>% EP1, <NUM>% AF, <NUM>% LCD4115, <NUM>% T403LiSt, <NUM>% CARBEZ3S. The prebond resin was cured to a non-tacky condition by passing the coated web through a convection oven at <NUM> °F (<NUM>) for <NUM> minutes, yielding a prebonded, nonwoven web of having a basis weight of <NUM> gsm.

A slurry was prepared, including precision shaped abrasive particles, with the slurry having the formula described in Table <NUM>. The slurry was prepared in batches with a weight of about <NUM> to about <NUM> using an air-powered high-shear mixer with the speed adjusted to generate a strong vortex in the slurry while mixing. The component order of addition was in the sequence listed in Table <NUM>.

Unitized abrasive wheels were prepared from the prebonded nonwoven web as follows. A <NUM>-inch (<NUM>-centimeter) × <NUM>-inch (<NUM>- centimeter) section was cut from the prebonded, nonwoven web and saturated with abrasive slurry. The saturated prebonded web was then passed through the nip of a roll coater, consisting of <NUM>-inch (<NUM>- centimeter) diameter rubber rolls of <NUM>-Shore A durometer hardness, to remove excess slurry until the desired slurry add-on weight of <NUM> gsm was obtained. Typically, the web passes through the nip at <NUM> feet per minute (<NUM> meters per minute) under pressures of <NUM>-<NUM> psi (<NUM>-<NUM> kilopascal) to reach the target weight. Four sections of prebonded web were coated with the slurry in the above manner. The coated sections of prebonded web were placed in a forced air oven set at <NUM> °F (<NUM>) for <NUM> minute to remove a majority of the solvent. In order to form a single, unitized slab of nonwoven, abrasive material, the four sections were then stacked one on top of the other and placed in a hydraulic, heated platen press set at <NUM> °F (<NUM>). A release liner was placed on both sides of the stack, prior to placing it in the oven. Consistent thickness of the unitized slab was maintained by placing <NUM> inch (<NUM> centimeters) thick metal spacers in each corner of the platen. Pressure (<NUM>,<NUM> psi, <NUM> megapascal), was applied to the platens. After <NUM> minutes, the two sections of web had fused together into a single, unitized slab. This slab was placed in a forced air oven set at <NUM> °F (<NUM>) for <NUM> minutes. After removal from the oven, the slab was cooled to room temperature, and a <NUM>-inch (<NUM>-centimeter) diameter <NUM>-inch (<NUM>-centimeter) thick unitized abrasive wheel with a <NUM>-inch (<NUM>-centimeter) center hole was die cut from it using a SAMCO SB-<NUM> swing beam press manufactured by Deutsche Vereinigte Schuhmaschinen GmbH & Co. , Frankfurt, Germany. The samples prepared are described in Table <NUM>.

The Abrasion Test measured the abrasive efficiency of comparative test wheels and was conducted using a dual-spindle automated machine. A <NUM>-inch (<NUM>-centimeter) diameter <NUM>-inch (<NUM>-centimeter) thick test wheel mounted on one spindle and a <NUM>-inch (<NUM>-centimeter) diameter by <NUM>-inch (<NUM>-millimeter) thick carbon steel tube workpiece mounted on the other spindle. The workpiece was set to rotate at <NUM> revolutions per minute and the abrasive wheel was set to rotate at <NUM> revolutions per minute. The abrasive wheel and the workpiece could be urged together at a load of <NUM> pounds (<NUM> kilograms). During the test, the end of the pre-weighed rotating tube was urged against the pre-weighed wheel at the selected test load for <NUM>-second intervals followed by a noncontact period of <NUM> seconds. Each Abrasion Test ran for a total of <NUM> minutes with the total time the workpiece contacted the wheel being <NUM> minutes. Total Cut was determined by the weight loss of the workpiece and the Wheel Wear was determined by the weight loss of the abrasive wheel. Results were reported as Cut and Wear in grams for each test wheel. The grams of steel cut, and the grams of wheel worn, are illustrated in Table <NUM>.

<FIG> is a plot illustrating wear of the wheel sample versus wt% <NUM> denier fiber in the prebond of the wheel, for various sizes of abrasive particles. <FIG> is a plot illustrating cut of steel versus wt% FIB <NUM> (wt% of total fiber), for various sizes of abrasive particles. Table <NUM> gives normalized values for cut, wear, and efficiency (cut divided by wear), with values for cut and wear normalized to a value of <NUM> for prebonds containing <NUM>% FIB1 for each different abrasive particle, with the remaining fiber blends' cut and wear values being a ratio of the <NUM>% FIB1 cut and wear values. <FIG> illustrates normalized cut versus wt% FIB1 (wt% of total fiber). <FIG> illustrates normalized wear versus wt% FIB1 (wt% of total fiber). <FIG> illustrates normalized efficiency versus wt% FIB <NUM>.

Claim 1:
A nonwoven abrasive article comprising:
a nonwoven web comprising first fibers having a first diameter and second fibers having a second diameter, wherein the first diameter is different than the second diameter; and
abrasive particles distributed throughout at least a portion of the nonwoven web;
characterized in that the abrasive particles are shaped particles; and
the first fibers have a denier of at least <NUM> and no greater than <NUM>, the second fibers have a denier of at least <NUM>,
the first fibers are at least <NUM> wt% and no greater than <NUM> wt% of the fibers in the nonwoven web, and
the second fibers are at least <NUM> wt% and no greater than <NUM> wt% of the fibers in the nonwoven web.