Patent Description:
Conventional buffs and buffing wheels (collectively referred to herein as "buffs") are used to polish parts made of metal, plastic, ceramic, glass, wood, stone, silicon, an optical materials, among others. Buffing is a finishing process which is typically accomplished after more rigorous stock removal treatment of a surface.

Buffs are frequently categorized as either "cut" buffs or "color" buffs. A "cut" buff is more aggressive and is typically employed with a coarser buffing compound, a medium to high pressure between the buff and the work piece, and the work piece is advanced against the direction of rotation of the buff. This results in the refinement of scratches on the work piece and yields a uniform matte finish. In contrast, a "color" buff is typically employed with a finer buffing compound, a medium to low pressure between the buff and the work piece, and the work piece is advanced in the direction of rotation of the buff. Application of a color buff results in a further refinement of scratches in the surface of the work piece and yields a reflective, mirror-like finish.

Conventional buffs are typically free of any fixed abrasive material. Instead, abrasive emulsions or solid waxy abrasive compounds are externally applied to the working surface of the buff, and periodically reapplied, during abrasive operations. Conventional buffing systems have various draw backs including high costs of maintaining and cleaning the abrasive compound transport and application systems, high material waste during buffing processes, and costs and concerns associated with disposal of abrasive compounds.

Therefore, there continues to be a demand for improved abrasive products and methods that can offer enhanced abrasive processing performance, efficiency, and improved surface quality.

From <CIT> there is known a fixed abrasive buff comprising a plurality of fixed abrasive cloths and a central hub, wherein the fixed abrasive cloths are attached to the hub, wherein each abrasive cloth comprises an abrasive composition fixed to a fabric, wherein the fabric comprises a woven fabric, a nonwoven fabric, or a combination thereof, wherein the abrasive composition comprises a polymeric binder and a plurality of abrasive particles dispersed in the polymeric binder, wherein the abrasive composition is disposed within the fibers of the fabric, wherein the fabric comprises a fabric thickness and wherein the abrasive composition comprises an abrasive composition thickness.

Skilled artisans appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the invention.

The following description in combination with the figures is provided to assist in understanding the teachings disclosed herein. The following discussion will focus on specific implementations and embodiments of the teachings. This focus is provided to assist in describing the teachings and should not be interpreted as a limitation on the scope or applicability of the teachings. However, other embodiments can be used based on the teachings as disclosed in this application.

As used herein, the term "aggregate" may be used to refer to a particle made of a plurality of smaller particles that have been combined in such a manner that it is relatively difficult to separate or disintegrate the aggregate particle into smaller particles by the application of pressure or agitation. This is in contrast to the term "agglomerate," which is used herein to refer to a particle made up of a plurality of smaller particles that have been combined in such a manner that it is relatively easy to separate the agglomerate particle or disintegrate the agglomerate particle back into smaller particles, such as by the application of pressure or hand agitation.

The materials, methods, and examples are illustrative only and not intended to be limiting. To the extent not described herein, many details regarding specific materials and processing acts are conventional and may be found in textbooks and other sources within the abrasive arts.

<FIG> shows an image of an embodiment of an abrasive buffing article (<NUM>) ("abrasive buff") comprising: a plurality of woven fabric layers (<NUM>). An abrasive composition is fixed to each of the fabric layers. Each of the fabric layers comprises a plurality of yarns, wherein the abrasive composition is disposed at least partially within the yarns and/or between the yarns. The abrasive composition comprises a polymeric binder and a plurality of abrasive particles dispersed in the polymeric binder.

<FIG> shows a process flow diagram of a method <NUM> of forming an abrasive buff. Step <NUM> comprises mixing together a plurality of abrasive grains and a polymeric binder to form a precursor composition. In an embodiment, the abrasive grains can comprise abrasive aggregates. Step <NUM> comprises impregnating a woven fabric with the precursor composition. In an embodiment, the abrasive grains penetrate into and between the fibers of the woven fabric. In an embodiment, the precursor composition can be disposed on both surfaces (i.e., the front side and the back side) of the woven fabric. Step <NUM> comprises curing the precursor composition to form an abrasive woven cloth. Step <NUM> comprises forming the abrasive woven cloth into an abrasive buff.

<FIG> is an image of a surface of a woven fabric substrate of an abrasive buff where an abrasive composition (i.e., abrasive grains dispersed in a polymeric binder composition) is disposed on and in the fabric such that the abrasive composition (including the abrasive grains) penetrate into and between the fibers of the woven fabric substrate according to an embodiment.

<FIG> is a cross sectional image of the same embodiment shown in <FIG> and shows that the abrasive composition is disposed on both surfaces (i.e., the front side and the back side) of the woven fabric substrate. The abrasive composition (including the abrasive grains) is penetrating into and between the fibers of the woven fabric.

The abrasive fabric of the abrasive buff can comprise varying amounts of abrasive composition. In an embodiment, the amount of abrasive composition can comprise as least <NUM> wt% of the abrasive fabric, such as at least <NUM>% wt%, at least <NUM> wt%, at least <NUM> wt%, at least <NUM> wt%, or at least <NUM> wt% of the abrasive fabric. In another embodiment, the abrasive composition can comprise not greater than <NUM> wt% of the abrasive fabric, such as not greater than <NUM> wt%, not greater than <NUM> wt%, not greater than <NUM> wt%, not greater than <NUM> wt%, not greater than <NUM> wt%, or not greater than <NUM> wt% of the abrasive fabric. The amount of the abrasive composition can be within a range of any minimum or maximum value noted above. In a specific embodiment, the amount of the abrasive composition can comprise from at least <NUM> wt% to not greater than <NUM> wt% of the abrasive fabric, such as at least <NUM> wt% to not greater than <NUM> wt% of the abrasive fabric, such as at least <NUM> wt% to not greater than <NUM> wt% of the abrasive fabric, such as at least <NUM> wt% to not greater than <NUM> wt% of the abrasive fabric.

The abrasive fabric of the abrasive buff can comprise varying amounts of fabric. In an embodiment, the amount of fabric can comprise as least <NUM> wt% of the abrasive fabric, such as at least <NUM>% wt%, at least <NUM> wt%, at least <NUM> wt%, at least <NUM> wt%, or at least <NUM> wt% of the abrasive fabric. In another embodiment, the fabric can comprise not greater than <NUM> wt% of the abrasive fabric, such as not greater than <NUM> wt%, not greater than <NUM> wt%, not greater than <NUM> wt%, or not greater than <NUM> wt% of the abrasive fabric. The amount of the fabric can be within a range of any minimum or maximum value noted above. In a specific embodiment, the amount of the fabric can comprise from at least <NUM> wt% to not greater than <NUM> wt% of the abrasive fabric, such as at least <NUM> wt% to not greater than <NUM> wt% of the abrasive fabric.

Alternatively, the amount of abrasive composition comprising the abrasive fabric can be expressed as an amount or "weight" (mass per unit area) of an abrasive composition added to the fabric (i.e., add-on weight). In an embodiment, the add-on weight can comprise at least <NUM> grams per square meter ("GSM"), such as least <NUM> GSM, at least <NUM> GSM, at least <NUM> GSM, at least <NUM> GSM, or at least <NUM> GSM. In another embodiment, the add-on weight can comprise not greater than <NUM> GSM, such as not greater than <NUM> GSM, not greater than <NUM> GSM, not greater than <NUM> GSM, not greater than <NUM> GSM, not greater than <NUM> GSM, not greater than <NUM> GSM, not greater than <NUM> GSM, not greater than <NUM> GSM, or not greater than <NUM> GSM. The add-on weight can be within a range of any minimum or maximum value noted above. In a specific embodiment, the add-on weight can comprise a weight of at least <NUM> GSM to not greater than <NUM> GSM, such as at least <NUM> GSM to not greater than <NUM> GSM, as at least <NUM> GSM to not greater than <NUM> GSM.

An abrasive buff can comprise a plurality of fabric layers. In an embodiment, each of the fabric layers can comprise an abrasive composition fixed to each of the fabric layers. In an embodiment, the fabric layers can comprise a woven fabric, a nonwoven fabric, or a combination thereof. In an embodiment, the abrasive composition can be disposed on a first side of the fabric. In an embodiment, the abrasive composition is further disposed on a second side of the fabric.

In a specific embodiment, the fabric comprises a woven fabric. In an embodiment, the woven fabric can comprise a plurality of yarns, such as warp yarns and weft yarns. In an embodiment, the abrasive composition can be disposed at least partially within or between the yarns, such as between the warp and weft yarns. In an embodiment, the abrasive composition can be further disposed through the fabric between the yarns from the first side of the fabric to the second side of the fabric.

In another specific embodiment, the fabric comprises a nonwoven fabric. As used herein the term "nonwoven fabric or web" means a web having a structure of individual fibers or threads that are interlaid, but not in an identifiable manner as in a knitted fabric. Nonwoven fabrics or webs can be formed from many processes such as for example, meltblowing processes, spunbonding processes, and bonded carded web processes. The basis weight of a nonwoven fabric is usually expressed in ounces of material per square yard (osy) or grams per square meter (gsm) and the fiber diameters are usually expressed in microns. (Note that to convert from osy to gsm, multiply osy by <NUM>). In an embodiment, the nonwoven fabric can comprise a spunbond fabric (also known as a "spunlaid" fabric) of spunbonded fibers. "Spunbonded fibers" refers to small diameter fibers that are formed by extruding molten thermoplastic material as filaments from a plurality of fine, usually circular capillaries of a spinneret with the diameter of the extruded filaments then being rapidly reduced. Spunbond fibers are generally not tacky when they are deposited onto a collecting surface. Spunbond fibers are generally continuous.

In an embodiment, a spunbond fabric can comprise a meltblown fabric of meltblown fibers. "Meltblown fibers" means fibers formed by extruding a molten thermoplastic material through a plurality of fine, usually circular, die capillaries as molten threads or filaments into converging high velocity, usually hot, gas (e.g. air) streams that attenuate the filaments of molten thermoplastic material to reduce their diameter, which may be to microfiber diameter.

Thereafter, the meltblown fibers are carried by the high velocity gas stream and are deposited on a collecting surface to form a web of randomly disbursed meltblown fibers. Meltblown fibers are microfibers that may be continuous or discontinuous, are generally smaller than <NUM> microns in average diameter, and are generally tacky when deposited onto a collecting surface.

In an embodiment, the spunbond fabric comprises bonds that hold the web together. In an embodiment, the bonds can comprise thermal bonds (thermal bonding), hydroentangling bonds, resin bonds, or a combination thereof. Thermal bonding can comprise flat bonding, point bonding (also known as pattern bonding), and through-air bonding. Flat bonding occurs by applying heat and consistent pressure in the form of a flat calender across the web, which creates a smooth surface of fibers bonded to each other. Point bonding (also known as pattern bonding) is the process of applying a heated roll with a pattern embossed in the roll. Fibers are bonded together only at the specific pattern points of the roll. Alternatively, point bonding can be accomplished by ultrasonic welding. Point bonding can comprise any or a combination of various point bonding patterns, such as an S-weave pattern, an Expanded Hansen-Pennings (EHP) pattern, a wire weave pattern, a Point Unbonded Pattern (PUB), or a combination thereof. Thru-air bonding draws the web through a heated drum, creating bonds throughout the fabric without applying a specific pressure to the web. In a specific embodiment, the fabric can comprise a nonwoven, spunbond, point bond fabric.

In an embodiment, the abrasive composition can be disposed at least partially within or between the fibers of the nonwoven web. In an embodiment, the abrasive composition can be further disposed through the nonwoven fabric between the fibers of the web from the first side of the fabric to the second side of the fabric.

An abrasive buff can comprise a plurality of fabric layers (also called "plys"). In an embodiment, the number of fabric layers can be at least <NUM> layers, such as at least <NUM> layers, at least <NUM> layers, at least <NUM> layers, or at least <NUM> layers. In another embodiment, the number of layers can be not greater than <NUM> layers, such as not greater than <NUM> layers, not greater than <NUM> layers, not greater than <NUM> layers, or not greater than <NUM> layers. The number of fabric layers can be within a range of any minimum or maximum value noted above. In a specific embodiment, the number of fabric layers can comprise from at least <NUM> layers to not greater than <NUM> layers, such as from at least <NUM> layers to not greater than <NUM> layers, at least <NUM> layers to not greater than <NUM> layers, or at least <NUM> layers to not greater than <NUM> layers.

In an embodiment, the fabric layer can comprise a woven cloth. In an embodiment, the woven cloth can comprise one or a plurality of woven patterns, including a plain weave, a basket weave, a rib weave, a balanced plain weave, a twill weave, a satin weave, or a combination thereof.

The thread count of a woven cloth can vary in the warp direction and vary in the weft direction, wherein <NUM> inch corresponds to <NUM>. In an embodiment, the woven cloth can comprise at least <NUM> threads per inch in the warp direction, such as least <NUM> threads per inch, at least <NUM> threads per inch, at least <NUM> threads per inch, at least <NUM> per inch, at least <NUM> threads per inch, at least <NUM> threads per inch, at least <NUM> threads per inch, or at least <NUM> threads per inch. In another embodiment, the woven cloth can comprise not greater than <NUM> threads per inch, such as not greater than <NUM> threads per inch, not greater than <NUM> threads per inch, not greater than <NUM> threads per inch, not greater than <NUM> threads per inch, or not greater than <NUM> threads per inch. The threads per inch can be within a range of any minimum or maximum value noted above. In a specific embodiment, the amount of threads per inch can comprise from at least <NUM> threads per inch to not greater than <NUM> threads per inch in the warp direction, such as from <NUM> threads per inch to not greater than <NUM> threads per inch, or from <NUM> threads per inch to not greater than <NUM> threads per inch.

The thread count of a woven cloth can vary in the weft direction and vary in the weft direction. In an embodiment, the woven cloth can comprise at least <NUM> threads per inch in the weft direction, such as least <NUM> threads per inch, at least <NUM> threads per inch, at least <NUM> threads per inch, at least <NUM> per inch, at least <NUM> threads per inch, at least <NUM> threads per inch, at least <NUM> threads per inch, or at least <NUM> threads per inch. In another embodiment, the woven cloth can comprise not greater than <NUM> threads per inch, such as not greater than <NUM> threads per inch, not greater than <NUM> threads per inch, not greater than <NUM> threads per inch, not greater than <NUM> threads per inch, or not greater than <NUM> threads per inch. The threads per inch can be within a range of any minimum or maximum value noted above. In a specific embodiment, the amount of threads per inch can comprise from at least <NUM> threads per inch to not greater than <NUM> threads per inch in the weft direction, such as from <NUM> threads per inch to not greater than <NUM> threads per inch, or from <NUM> threads per inch to not greater than <NUM> threads per inch.

The ratio of warp threads to weft threads of a woven fabric layer can vary. In an embodiment, the woven cloth comprises a ratio of warp threads to weft threads (warp:weft) ranging from <NUM>:<NUM> (e.g., <NUM>/<NUM> thread count) to <NUM>:<NUM> (e.g., <NUM>/<NUM> thread count), such as from <NUM>:<NUM> to <NUM>:<NUM>, or from <NUM>:<NUM> to <NUM>:<NUM>.

The "weight" (mass per area) of a fabric (whether woven or nonwoven) can vary. In an embodiment, the fabric weight can comprise at least <NUM> grams per square meter ("GSM")(g/m<NUM>), such as least <NUM> GSM, at least <NUM> GSM, at least <NUM> GSM, at least <NUM> GSM, or at least <NUM> GSM. In another embodiment, the fabric weight can comprise not greater than <NUM> GSM GSM, such as not greater than <NUM> GSM, not greater than <NUM> GSM, not greater than <NUM> GSM, not greater than <NUM> GSM, not greater than <NUM> GSM, not greater than <NUM> GSM, not greater than <NUM> GSM, not greater than <NUM> GSM, or not greater than <NUM> GSM. The fabric weight can be within a range of any minimum or maximum value noted above. In a specific embodiment, the fabric weight can comprise a weight of at least <NUM> GSM to not greater than <NUM> GSM, such as at least <NUM> GSM to not greater than <NUM> GSM, as at least <NUM> GSM to not greater than <NUM> GSM, or at least <NUM> GSM to not greater than <NUM> GSM.

The ratio of fabric weight to abrasive composition add-on weight ("add-on weight") can vary and can beneficially affect the performance of the fixed abrasive buff. In an embodiment, the ratio of fabric weight to add-on weight (fabric weight: add-on weight) can range from <NUM>:<NUM> to <NUM>:<NUM>, such as from <NUM>:<NUM> to <NUM>:<NUM>, or from <NUM>:<NUM> to <NUM>:<NUM>.

The fabric can comprise natural fibers, synthetic fibers, or a combination thereof. Natural fibers can comprise one or more natural fibers. In an embodiment, natural fibers can comprise cellulose, cotton, flax, hemp, jute, ramie, sisal, linen, silk, or a combination thereof. In another embodiment, natural fibers can comprise cotton. In a specific embodiment, natural fibers can consist essentially of cotton. Synthetic fibers can comprise one or more synthetic fibers. In an embodiment, synthetic fibers can comprise a polymer, a glass, a metal, a rubber, carbon, or a combination thereof. In another embodiment, synthetic fibers can comprise a polymer fiber. In a specific embodiment, a polymer fiber can comprise nylon, acrylic, olefin, polyester, rayon, modal, Dyneema, or a combination thereof. In a particular embodiment, a polymer fiber comprises polyester. In a specific embodiment, a synthetic fiber can consist essentially of polyester. In another particular embodiment, a polymer fiber comprises nylon. In a specific embodiment, a synthetic fiber can consist essentially of nylon.

The fabric can have a specific grain. For woven textiles, grain refers to the orientation of the weft and warp threads. The fabric grain can be a straight grain, a cross grain, or a bias grain. A fabric can be cut in any orientation and the chosen grain will affect the way the fabric hangs and stretches. Generally, a piece of fabric is said to be cut on a particular grain when the main seams of the finished piece are aligned with that grain. A fabric has a bias grain (or "a bias") when the fabric's warp and weft threads are at <NUM> degrees to its major seam lines. In an embodiment, the fabric comprises a bias. <FIG> illustrates an embodiment of a fabric having a bias. In a specific embodiment, the fabric of a fixed abrasive buff can be biased so that the warp and weft lines are in <NUM> degree contact angle on a work piece. In an embodiment, the fabric comprises a bias to prevent fraying and wear of the warp and/or weft lines.

The thickness of a fabric can vary and can beneficially affect the performance of the fixed abrasive buff. In an embodiment, the fabric thickness can comprise at least <NUM> microns, such as least <NUM> microns, at least <NUM> microns, at least <NUM> microns, at least <NUM> microns, at least <NUM> microns, at least <NUM> microns, or at least <NUM> microns. In another embodiment, the fabric thickness can comprise not greater than <NUM> microns, such as not greater than <NUM> microns, not greater than <NUM> microns, not greater than <NUM> microns, not greater than <NUM> microns, not greater than <NUM> microns, not greater than <NUM> microns, not greater than <NUM> microns, not greater than <NUM> microns, not greater than <NUM> microns, not greater than <NUM> microns, not greater than <NUM> microns, not greater than <NUM> microns, not greater than <NUM> microns, or not greater than <NUM> microns. The fabric thickness can be within a range of any minimum or maximum value noted above. In a specific embodiment, the fabric thickness can comprise a thickness of at least <NUM> microns to not greater than <NUM> microns, such as at least <NUM> microns to not greater than <NUM> microns, at least <NUM> microns to not greater than <NUM> microns, <NUM> microns to not greater than <NUM> microns, as at least <NUM> microns to not greater than <NUM> microns.

The abrasive buff comprises an abrasive composition fixed to each of the fabric layers. The abrasive composition can comprise a plurality of abrasive particles (also called abrasive grains herein) disposed on or in a polymeric binder. In an embodiment, the abrasive composition can further comprise a rheology modifier.

The amount of abrasive particles comprising the abrasive composition can vary. In an embodiment, the abrasive composition can comprise at least <NUM> wt% abrasive particles, such as least <NUM> wt%, at least <NUM> wt%, at least <NUM> wt%, at least <NUM> wt%, at least <NUM> wt%, at least <NUM> wt%, at least <NUM> wt%, or at least <NUM> wt% abrasive particles. In another embodiment, the abrasive composition can comprise not greater than <NUM> wt% abrasive particles, such as not greater than <NUM> wt%, not greater than <NUM> wt%, or not greater than 75wt% abrasive particles. The abrasive particles can be within a range of any minimum or maximum value noted above. In a specific embodiment, the amount of abrasive particles in the abrasive composition can comprise from at least 20wt% to not greater than 90wt%, such as from at least <NUM> wt% to not greater than <NUM> wt%, or from <NUM> wt% abrasive particles to not greater than <NUM> wt% abrasive particles.

The amount of polymeric binder comprising the abrasive composition can vary. In an embodiment, the abrasive composition can comprise at least <NUM> wt% polymeric binder, such as least <NUM> wt%, at least <NUM> wt%, or at least <NUM> wt% polymeric binder. In another embodiment, the abrasive composition can comprise not greater than <NUM> wt% polymeric binder, such as not greater than <NUM> wt%, not greater than <NUM> wt%, not greater than <NUM> wt%, not greater than <NUM> wt%, not greater than <NUM> wt%, not greater than <NUM> wt%, not greater than <NUM> wt%, not greater than <NUM> wt%, or not greater than 30wt% polymeric binder. The polymeric binder can be within a range of any minimum or maximum value noted above. In a specific embodiment, the amount of polymeric binder in the abrasive composition can comprise from at least <NUM> wt% to not greater than 80wt%, such as from at least <NUM> wt% to not greater than <NUM> wt%, or from <NUM> wt% polymeric binder to not greater than <NUM> wt% polymeric binder.

The amount of rheology modifier (also called a thickener herein) comprising the abrasive composition can vary. In an embodiment, the abrasive composition can comprise at least <NUM> wt% rheology modifier, such as least <NUM> wt%, at least <NUM> wt%, or at least <NUM> wt% rheology modifier. In another embodiment, the abrasive composition can comprise not greater than <NUM> wt% rheology modifier, such as not greater than <NUM> wt%, not greater than <NUM> wt%, not greater than <NUM> wt%, or not greater than <NUM> wt%. The rheology modifier can be within a range of any minimum or maximum value noted above. In a specific embodiment, the amount of rheology modifier in the abrasive composition can comprise from at least <NUM> wt% to not greater than 10wt%, such as from at least <NUM> wt% to not greater than <NUM> wt%.

The total thickness of the abrasive composition (i.e., the total abrasive coating thickness) can vary and can beneficially affect the performance of the fixed abrasive buff. It will be appreciated that if the abrasive fabric is coated on one side only, the total abrasive coating thickness will be equal to the thickness of the coating on one side. Similarly, if the abrasive fabric is coated on both sides, the total abrasive coating thickness will be equal to the sum of the thickness of the coating on both sides. In an embodiment, the total abrasive coating thickness can comprise at least <NUM> microns, such as least <NUM> microns, at least <NUM> microns, at least <NUM> microns, at least <NUM> microns, at least <NUM> microns, or at least <NUM> microns. In another embodiment, the abrasive coating thickness can comprise not greater than <NUM> microns, such as not greater than <NUM> microns, not greater than <NUM> microns, not greater than <NUM> microns, not greater than <NUM> microns, not greater than <NUM> microns, not greater than <NUM> microns, or not greater than <NUM> microns. The abrasive coating thickness can be within a range of any minimum or maximum value noted above. In a specific embodiment, the abrasive coating thickness can comprise a thickness of at least <NUM> microns to not greater than <NUM> microns, such as at least <NUM> microns to not greater than <NUM> microns, as at least <NUM> microns to not greater than <NUM> microns.

The ratio of fabric thickness to abrasive composition add-on thickness ("add-on thickness") can vary and can beneficially affect the performance of the fixed abrasive buff. In an embodiment, the ratio of fabric thickness to add-on thickness (fabric thickness: add-on thickness) can range from <NUM>:<NUM> to <NUM>:<NUM>, such as from <NUM>:<NUM> to <NUM>:<NUM>, or from <NUM>:<NUM> to <NUM>:<NUM>.

Abrasive particles can include essentially single phase inorganic materials, such as alumina, silicon carbide, silica, ceria, and harder, high performance superabrasive particles such as cubic boron nitride and diamond. Additionally, the abrasive particles can include composite particulate materials. Such materials can include aggregates, which can be formed through slurry processing pathways that include removal of the liquid carrier through volatilization or evaporation, leaving behind unfired ("green") aggregates, that can optionally undergo high temperature treatment (i.e., firing, sintering) to form usable, fired aggregates. Further, the abrasive regions can include engineered abrasives including macrostructures and particular three-dimensional structures. In certain embodiments, the abrasive particles comprise primary particles, aggregates, or a combination thereof. In certain embodiments, when the abrasive particles are at least partially abrasive aggregates, the abrasive aggregates may comprise unfired abrasive aggregates having a generally spheroidal or toroidal shape that are formed from a composition of abrasive grit particles and a nanoparticle binder (Nanozyte aggregates). In certain embodiments, the aggregates may be hollow and may comprise an interior space (Nanozyte aggregates).

In an embodiment, the abrasive particles are blended with a polymeric binder to form abrasive slurry. Alternatively, the abrasive particles are applied over the polymeric binder after the polymeric binder is coated on the backing. Optionally, a functional powder can be applied over the abrasive regions to prevent the abrasive regions from sticking to a patterning tooling. Alternatively, patterns can be formed in the abrasive regions absent the functional powder.

The abrasive particles can be formed of any one of or a combination of abrasive particles, including silica, alumina (fused or sintered), zirconia, zirconialalumina oxides, silicon carbide, garnet, diamond, cubic boron nitride, silicon nitride, ceria, titanium dioxide, titanium diboride, boron carbide, tin oxide, tungsten carbide, titanium carbide, iron oxide, chromia, flint, emery, and Tripoli. For example, the abrasive particles can be selected from a group consisting of silica, alumina, zirconia, silicon carbide, silicon nitride, boron nitride, garnet, diamond, co-fused alumina zirconia, ceria, titanium diboride, boron carbide, flint, emery, alumina nitride, and a blend thereof. Particular embodiments have been created by use of dense abrasive particles comprised principally of alpha-alumina.

The abrasive grain can also have a particular shape. An example of such a shape includes a rod, a triangle, a pyramid, a cone, a solid sphere, a hollow sphere, or the like. Alternatively, the abrasive grain can be randomly shaped.

In certain embodiments, a portion of the abrasive particles of the aggregate component may include a coating of a polymer component disposed between the abrasive particle and the polymeric binder. In certain embodiments, the polymer component may be directly in contact with the abrasive particles.

In an embodiment, the abrasive particles can have an average particle size not greater than <NUM> microns, such as not greater than <NUM> microns, such as not greater than about <NUM> microns, not greater than about <NUM> microns, not greater than about <NUM> microns, not greater than about <NUM> microns, not greater than about <NUM> microns, not greater than about <NUM> microns, or not greater than <NUM> microns. In another embodiment, the abrasive particle size can be at least <NUM> microns, such as at least <NUM> micron, at least <NUM> microns, at least <NUM> microns, at least <NUM> microns, at least <NUM> microns, at least <NUM> microns, at least <NUM> microns, at least <NUM> microns, at least <NUM> microns, or at least <NUM> microns. The average particle size can be within a range of any minimum or maximum value noted above. In a specific embodiment, the average particle size can comprise from at least <NUM> micron to not greater than <NUM> microns, such as from at least <NUM> microns to not greater than <NUM> microns, at least <NUM> microns to not greater than <NUM> microns, at least <NUM> microns to not greater than <NUM> microns, at least <NUM> microns to not greater than <NUM> microns, or at least <NUM> microns to not greater than <NUM> microns. The particle size of the abrasive particles is typically specified to be the longest dimension of the abrasive particle. Generally, there is a range distribution of particle sizes. In some instances, the particle size distribution is tightly controlled.

The polymeric binder can be formed of a single polymer or a blend of polymers. The binder composition can be formed from an epoxy composition, acrylic composition, a phenolic composition, a polyurethane composition, a phenolic composition, a polysiloxane composition, an acrylic latex composition, a thermoset rubber composition, a thermoset elastomer composition, a styrene butadiene rubber composition, an acrylonitrile-butadiene rubber composition, a polybutadiene composition, or a combination thereof. In a specific embodiment, the polymeric binder can comprise a self crosslinking carboxylated styrene butadiene composition. In another specific embodiment, the polymeric binder can comprise a carboxylated acrylic composition. In addition, the binder composition can include active filler particles, as described above, additives, or a combination thereof. In certain embodiments, the polymeric binder can be flexible after curing such that the coated fabric has a "soft" hand, also known as a soft "drape", so that the fabric feels soft to the touch, is flexible, and conformable around an object, not stiff.

The polymeric binder generally includes a polymer matrix, which binds abrasive particles to the backing or to a compliant coat, if such a compliant coat is present. Typically, the polymeric binder is formed of cured polymeric binder. In an embodiment, the polymeric binder includes a polymer component and a dispersed phase.

The polymeric binder can include one or more reaction constituents or polymer constituents for the preparation of a polymer. A polymer constituent can include a monomeric molecule, a polymeric molecule, or a combination thereof. The polymeric binder can further comprise components selected from the group consisting of solvents, plasticizers, chain transfer agents, catalysts, stabilizers, dispersants, curing agents, reaction mediators and agents for influencing the fluidity of the dispersion.

The polymer constituents can form thermoplastics or thermosets. By way of example, the polymer constituents can include monomers and resins for the formation of polyurethane, polyurea, polymerized epoxy, polyester, polyimide, polysiloxanes (silicones), polymerized alkyd, styrene-butadiene rubber, acrylonitrile-butadiene rubber, polybutadiene, or, in general, reactive resins for the production of thermoset polymers. Another example includes an acrylate or a methacrylate polymer constituent. The precursor polymer constituents are typically curable organic material (i.e., a polymer monomer or material capable of polymerizing or crosslinking upon exposure to heat or other sources of energy, such as electron beam, ultraviolet light, visible light, etc., or with time upon the addition of a chemical catalyst, moisture, or other agent which cause the polymer to cure or polymerize). A precursor polymer constituent example includes a reactive constituent for the formation of an amino polymer or an aminoplast polymer, such as alkylated urea-formaldehyde polymer, melamine-formaldehyde polymer, and alkylated benzoguanamine-formaldehyde polymer; acrylate polymer including acrylate and methacrylate polymer, alkyl acrylate, acrylated epoxy, acrylated urethane, acrylated polyester, acrylated polyether, vinyl ether, acrylated oil, or acrylated silicone; alkyd polymer such as urethane alkyd polymer; polyester polymer; reactive urethane polymer; phenolic polymer such as resole and novolac polymer; phenolic/latex polymer; epoxy polymer such as bisphenol epoxy polymer; isocyanate; isocyanurate; polysiloxane polymer including alkylalkoxysilane polymer; or reactive vinyl polymer. The polymeric binder can include a monomer, an oligomer, a polymer, or a combination thereof. In a particular embodiment, the polymeric binder includes monomers of at least two types of polymers that when cured can crosslink. For example, the binder formulation can include epoxy constituents and acrylic constituents that when cured form an epoxy/acrylic polymer. In a specific embodiment, the polymeric binder can comprise at least one of a polyurethane, a phenolic, an acrylic latex, or a combination thereof.

The polymeric binder can comprise a desirable glass transition temperature (Tg) that can contribute to beneficial abrasive properties. In an embodiment, the polymeric binder can comprise a glass transition temperature (Tg) of not greater than <NUM>, not greater than <NUM>, not greater than <NUM>, not greater than <NUM>, not greater than <NUM>, not greater than <NUM>, not greater than <NUM>, or not greater than -<NUM>. In another embodiment, the polymeric binder can comprise a glass transition temperature (Tg) of at least -<NUM>, at least -<NUM>, at least - <NUM>, or at least -<NUM>. The glass transition temperature (Tg) can be within a range of any minimum or maximum value noted above. In a specific embodiment, the glass transition temperature (Tg) can comprise from at least -<NUM> to not greater than <NUM>, such as from at least -<NUM> to not greater than <NUM>. In a specific embodiment, the polymeric binder comprises a glass transition temperature (Tg) in a range of at least -<NUM> to not greater than - <NUM>, such as -<NUM> to not greater than -<NUM>. In a another specific embodiment, the polymeric binder comprises a glass transition temperature (Tg) in a range of at least -<NUM> to not greater than <NUM>, such as -<NUM> to not greater than <NUM>.

In an embodiment, the abrasive composition can comprise a rheology modifier. The rheology modifier can comprise a cellulose composition, a fumed silica composition, a colloidal silicate composition, a polysaccharide composition, or a combination thereof. In a specific embodiment, the cellulose composition can comprise a hydroxypropyl cellulose composition. In another specific embodiment, the colloidal silicate composition can comprise a layered colloidal silicate composition, such as laponite, a synthetic smectite clay that is a layered hydrous magnesium silicate. In another specific embodiment, the polysaccharide composition can comprise a gum composition, such as a Xanthan gum composition.

The properties and advantage of the present disclosure are illustrated in further detail in the following nonlimiting examples. Unless otherwise indicated, temperatures are expressed in degrees Celsius, pressure is ambient, and concentrations are expressed in weight percentages.

Sample abrasive compositions S1-S2 having different types and amounts of abrasive particles and polymeric binder were prepared using the formulations listed in Table <NUM>. The components were thoroughly mixed together and the resulting compositions were stored for later use. The formulations are presented on a "dry" weight (i.e., cured) basis.

The sample abrasive compositions S1-S2 were used to prepare various abrasive cloths. The construction of abrasive cloths S3-S6 is shown in Table <NUM>.

An uncoated "blank" cloth according to Table <NUM> was unwound from a roll and dipped in the sample abrasive compositions using a dip tank. <FIG> depict non-woven material T30 and T70 prior to coating, respectively. A portion of the uncoated <NUM>/<NUM> Greige cloth was used as a control (C1). The dipped cloth was run through metering rolls to remove excess liquid. <FIG> shows an embodiment of the dipping step. The impregnated fabric was passed through an oven to cure the abrasive composition. The cured abrasive cloth was collected on a winding station for further processing. Abrasive sample cloths S3-S6 were produced as described. A portion of the sample abrasive cloths were cut into <NUM>-inch OD circles ("discs") for fabric analysis. The results of the testing are shown in Table <NUM>.

<FIG> show images of abrasive cloth sample S4. <FIG> show images of abrasive cloth sample S5.

Buff wheels were created according to conventional methods (Garfield Buff Company, Fairfield, NJ). The sample abrasive cloths were tucked into a metal clinch ring and a metal plate with center ("arbor") hole was inserted. The buff wheel specifications were: <NUM> plys, <NUM>" OD, <NUM>" ID, arbor hole <NUM>/<NUM>".

Abrasive testing of sample fixed abrasive buffs S3-S6 was conducted on an Heald Cinternal cylindrical grinder. The goal was to investigate the polishing and wear behavior of the fixed abrasive buffs in an automated process compared to traditional bar compound buffing by hand. <FIG> displays the test setup.

Test workpieces were brass door knobs. Testing was directed to surface finish refinement and surface gloss improvement of rough workpiece. The initial surface of the workpieces were pre-ground with a grinding belt to an initial surface roughness Ra of <NUM>-<NUM>µ inches. For comparison, one door knob from the field was used for comparison with the automated buffing results. The comparative part was then buffed with a control C1 and bar compound. The surface finish and surface gloss of both sides of the workpiece were measured. Buffing was conducted at a <NUM>° angle from the grinding marks as shown in <FIG>. All testing parameters are shown in Table <NUM>.

Sample inventive fixed abrasive buffs were tested against the conventional method of buffing (i.e., buffing with an uncoated buff and periodically applying traditional bar compound to the buff surface during buffing). The abrasive performance results after <NUM> second buffing time and <NUM> second buffing time are shown in Table <NUM>.

Sample abrasive compositions S7-S9 having different types and amounts of abrasive particles, polymeric binder, and rheology modifiers were prepared using the formulations listed in Table <NUM>. The components were thoroughly mixed together and the resulting compositions were stored for later use. The formulations are presented on a "dry" weight (i.e., cured) basis.

The specification and illustrations of the embodiments described herein are intended to provide a general understanding of the structure of the various embodiments. The specification and illustrations are not intended to serve as an exhaustive and comprehensive description of all of the elements and features of apparatus and systems that use the structures or methods described herein.

Claim 1:
A fixed abrasive buff comprising:
a plurality of fixed abrasive cloths; and
a central hub;
wherein the fixed abrasive cloths are attached to the hub; wherein each abrasive cloth comprises an abrasive composition fixed to a fabric; wherein the fabric comprises a woven fabric, a nonwoven fabric, or a combination thereof, wherein the abrasive composition comprises a polymeric binder and a plurality of abrasive particles dispersed in the polymeric binder; wherein the abrasive composition is disposed within the fibers of the fabric, wherein the fabric comprises a fabric thickness, wherein the abrasive composition comprises an abrasive composition thickness, and wherein the fixed abrasive buff comprises a ratio of fabric thickness to abrasive composition thickness ranging from <NUM>:<NUM> to <NUM>:<NUM>.