Technical Field

The present disclosure generally relates to an abrasive article and a method of forming the abrasive article.

Background

Abrasive articles are widely used by consumers, manufacturers, and service providers to perform sanding and finishing operations on a given substrate or a workpiece. Such workpieces may be diverse in nature and can have surfaces made of plastic, wood, metal, or ceramic materials.

In general, the abrasive articles include a plurality of abrasive particles bonded to a backing, which can be either rigid or flexible. The abrasive articles include a single layer or a plurality of layers of abrasive particles bonded to the backing. In some cases, the abrasive particles are uniformly mixed with a polymeric binder to form a slurry, which is then coated onto the backing and cured to provide the abrasive articles. In some other cases, the abrasive particles can be directly adhered to a surface of the backing by at least partially embedding them in curable resins.

Summary

In a first aspect, the present disclosure provides a method of forming an abrasive article. The method includes providing an abrasive sheet. The abrasive sheet includes an abrasive sheet backing including a first major surface and a second major surface opposite to the first major surface. The abrasive sheet further includes an abrasive layer including a plurality of abrasive particles. The abrasive layer is disposed on at least a portion of the first major surface of the abrasive sheet backing. The method further includes providing a transfer film. The transfer film includes a transfer film backing and a supersize coating composition. The supersize coating composition is disposed on the transfer film backing. The supersize coating composition is in solid-state. The method further includes placing the transfer film on the abrasive sheet, such that the supersize coating composition contacts at least the abrasive layer. The method further includes applying heat and/or pressure on at least one of the second major surface of the abrasive sheet backing and the transfer film backing to transfer the supersize coating composition to the abrasive sheet, such that the supersize coating composition is disposed at least partially on the abrasive layer. The method further includes removing the transfer film backing from the supersize coating composition.

In a second aspect, the present disclosure provides an abrasive article. The abrasive article includes an abrasive sheet backing including a first major surface and a second major surface opposite to the first major surface. The abrasive article further includes an abrasive layer comprising a plurality of abrasive particles. The abrasive layer is disposed on a portion of the first major surface of the abrasive sheet backing. The abrasive article further includes a supersize coating composition disposed on a portion of the abrasive layer and not on the remaining portion of the first major surface of the abrasive sheet backing.

The details of one or more examples of the disclosure are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the disclosure will be apparent from the description and drawings, and from the claims.

Brief Description of Drawings

Exemplary embodiments disclosed herein may be more completely understood in consideration of the following detailed description in connection with the following figures. The figures are not necessarily drawn to scale. Like numbers used in the figures refer to like components. However, it will be understood that the use of a number to refer to a component in a given figure is not intended to limit the component in another figure labeled with the same number.

FIG. 1 is a schematic sectional view of a segment of an abrasive article, according to an embodiment of the present disclosure;

FIG. 2 is a flowchart for a method of forming the abrasive article, according to an embodiment of the present disclosure;

FIGS. 3A-3F are schematic diagrams depicting various steps of the method of forming the abrasive article, according to an embodiment of the present disclosure;

FIG. 4 is a photomicrograph of an Example Abrasive, according to an embodiment of the present disclosure;

FIG. 5A is a photomicrograph of a segment of a transfer film, according to an embodiment of the present disclosure;

FIG. 5B is a schematic perspective view of a transfer film backing, according to an embodiment of the present disclosure; and

FIG. 6 is a photomicrograph of the Example Abrasive after an attempt to remove any loading from the Example Abrasive.

Detailed Description

In the following description, reference is made to the accompanying figures that form a part thereof and in which various embodiments are shown by way of illustration. It is to be understood that other embodiments are contemplated and may be made without departing from the scope or spirit of the present disclosure. The following detailed description, therefore, is not to be taken in a limiting sense.

In the following disclosure, the following definitions are adopted. As used herein, all numbers should be considered modified by the term “about”. As used herein, “a,” “an,” “the,” “at least one,” and “one or more” are used interchangeably.

As used herein as a modifier to a property or attribute, the term “generally”, unless otherwise specifically defined, means that the property or attribute would be readily recognizable by a person of ordinary skill but without requiring absolute precision or a perfect match (e.g., within +/- 20 % for quantifiable properties).

The term “substantially”, unless otherwise specifically defined, means to a high degree of approximation (e.g., within +/- 10% for quantifiable properties) but again without requiring absolute precision or a perfect match.

The term “about”, unless otherwise specifically defined, means to a high degree of approximation (e.g., within +/- 5% for quantifiable properties) but again without requiring absolute precision or a perfect match.

As used herein, the terms “first” and “second” are used as identifiers. Therefore, such terms should not be construed as limiting of this disclosure. The terms “first” and “second” when used in conjunction with a feature or an element can be interchanged throughout the embodiments of this disclosure.

As used herein, “at least one of A and B” should be understood to mean “only A, only B, or both A and B”.

As used herein, the recitations of numerical ranges by endpoints include all numbers subsumed within that range as well as the endpoints (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, 5, etc.).

As used herein, the term “liquid-state” refers a state of a composition that flows freely but is of a constant volume and (1) having a viscosity of under 20000 centipoise or (2) having a storage modulus of less than 0.03 megapascals, or less than 0.01 megapascals as measured using techniques of Standard Reference Material 2491, National Institute of Standards and Technology (2002).

As used herein, the term “solid-state” refers to a state of a composition having at least one of the following properties:

(1) at least 50% solid (non-volatile) components, at least 75% solid components, at least 80% solid components, at least 85% solid components, at least 90% solid components, or at least 95% solid components;

(2) no more than 10 weight percent volatile components, no more than 5 weight percent volatile components, no more than 1 weight percent volatile components, or no more than 0. 1 weight percent volatile components; and/or

(3) a storage modulus of at least 0.03 Megapascals, at least 0.3 Megapascals, at least 1.0 Megapascals, at least 3.0 Megapascals as measured using techniques of Standard Reference Material 2491, National Institute of Standards and Technology (2002).

Abrasive articles are widely used by consumers, manufacturers, and service providers to perform sanding and finishing operations on a given substrate or a workpiece. Such workpieces may be diverse in nature and can have surfaces made of plastic, wood, metal, or ceramic materials.

In general, the abrasive articles include a plurality of abrasive particles bonded to a backing, which can be either rigid or flexible. The abrasive articles include a single layer or a plurality of layers of abrasive particles bonded to the backing.

In some cases, the abrasive particles are uniformly mixed with a polymeric binder to form a slurry, which is then coated onto the backing and cured to provide the abrasive articles. In some other cases, the abrasive particles can be directly adhered to a surface of the backing by at least partially embedding them in curable resins.

Upon use, for example, during sanding, there may be an accumulation of sanding debris or swarf onto an abrasive surface of such abrasive articles. Such accumulation of swarf may be deleterious to an abrading performance of the abrasive articles due to its tendency to reduce a cutting ability of the abrasive particles. In order to reduce or limit the accumulation of swarf, a supersize coating including an antiloading composition is applied to the abrasive articles.

Conventionally, a liquid solution or suspension of the supersize coating is applied to the abrasive surface via a liquid coating process and the liquid solution is evaporated during a subsequent drying step. However, this process may lead to foam formation as the abrasive articles pass through, for example, liquid reservoirs during a roll coating process. Further, the foam formation may lead to defects and may have adverse effects on the aesthetics of the abrasive articles. In some cases, defoamer compositions may be added to the liquid solutions of the supersize coatings to reduce the foam formation but they may negatively affect the abrading performance of the abrasive articles.

In some cases, the liquid solution of the supersize coating applied to the abrasive surface via the liquid coating process may infiltrate underlying layers at the time of coating, which may adversely affect the abrading performance of the abrasive article.

Further, the liquid solution of the supersize coating applied to the abrasive surface via the liquid coating process may form a wicking pattern around the abrasive particles of the abrasive articles.

Furthermore, the liquid solution of the supersize coating may include stearate-based compositions. In such cases, the liquid solution may require surfactants to properly suspend the stearate- based compositions in the liquid solution. The surfactants may negatively impact performance of the supersize coating.

Moreover, in some cases, the abrasive article may include the abrasive particles bonded to a portion of the backing. For example, in some cases, the abrasive article may include the abrasive particles disposed on the backing in a predetermined pattern. Therefore, there may be regions of the abrasive article including the abrasive particles and forming the abrasive surface, and other regions not including the abrasive particles.

Conventional liquid coating processes for applying the liquid solution of the supersize coating to the abrasive surface of the abrasive articles may not be effective in such cases. Specifically, such liquid coating processes may not provide a controlled application of the liquid solution of the supersize coating to the regions of the abrasive article including the abrasive particles. This may lead to application of the liquid solution of the supersize coating to the regions not including the abrasive particles. This may lead to wastage of the liquid solution of the supersize coating and may further increase manufacturing costs.

According to aspects of this disclosure, an abrasive article and a method of forming the abrasive article are disclosed.

The method includes providing an abrasive sheet. The abrasive sheet includes an abrasive sheet backing including a first major surface and a second major surface opposite to the first major surface. The abrasive sheet further includes an abrasive layer including a plurality of abrasive particles. The abrasive layer is disposed on at least a portion of the first major surface of the abrasive sheet backing. The method further includes providing a transfer film. The transfer film includes a transfer film backing and a supersize coating composition. The supersize coating composition is disposed on the transfer film backing. The supersize coating composition is in solid-state. The method further includes placing the transfer film on the abrasive sheet, such that the supersize coating composition contacts at least the abrasive layer. The method further includes applying heat and/or pressure on at least one of the second major surface of the abrasive sheet backing and the transfer film backing to transfer the supersize coating composition to the abrasive sheet, such that the supersize coating composition is disposed at least partially on the abrasive layer. The method further includes removing the transfer film backing from the supersize coating composition.

Since the supersize coating composition is in solid-state, the method of forming the abrasive article of the present disclosure may prevent the foam formation which is otherwise caused due to conventional liquid coating processes. Thus, the aesthetics of the abrasive articles may be improved. Moreover, addition of the defoamer compositions, which negatively impact the abrading performance of the abrasive articles, may not be required.

Further, since the supersize coating composition is in solid-state, the method may further prevent formation of the wicking pattern around the abrasive particles of the abrasive articles which may be otherwise present due to conventional liquid coating processes.

Further, the evaporation and/or drying of the supersize coating composition may not be required. This may reduce drying costs in terms of equipment costs and/or energy costs, as well as reduce manufacturing time.

Furthermore, as the supersize coating composition is in solid-state, the supersize coating composition may not infiltrate into the abrasive layer to contact the underlying layers at the time of coating.

In addition, since the supersize coating composition is in solid-state, there may be no requirement of the surfactants, that are otherwise required to suspend the stearate-based compositions of the supersize coating composition.

Moreover, the supersize coating composition in solid-state may be applied to one or more desired locations of the abrasive sheet in a controlled manner. For example, it may be desirable to apply the supersize coating composition on a portion of the abrasive layer and not on the remaining portion of the first major surface of the abrasive sheet backing. This is because application of the supersize coating composition on the remaining portion of the first major surface of the abrasive sheet backing may negatively impact the abrasive sheet backing and may also lead to wastage of the supersize coating composition and thereby may increase manufacturing costs.

Additionally, since the supersize coating composition in solid-state may be applied to the one or more desired locations of the abrasive sheet in the controlled manner, the supersize coating composition may be applied in different shapes and patterns based on desired application attributes. In some cases, the supersize coating composition may be printed in different shapes and patterns on the transfer film and transferred to the one or more desired locations of the abrasive sheet.

FIG. 1 illustrates a schematic sectional view of a segment of an abrasive article 100, according to an embodiment of the present disclosure.

The abrasive article 100 includes an abrasive sheet backing 110. The abrasive sheet backing 110 includes a first major surface 112 and a second major surface 114 opposite to the first major surface 112.

In some embodiments, the abrasive sheet backing 110 includes a mesh, a paper, a polymer film, or a fabric. In some embodiments, the abrasive sheet backing 110 may include any suitable backing. For example, the abrasive sheet backing 110 may include a cloth, vulcanized rubber, a woven or nonwoven fibrous material, a fibrous reinforced thermoplastic backing, substrates containing hooked stems, looped fabrics, metal foils, foam backings, and laminated multilayer combinations thereof.

The mesh may be made of polymeric or metal open-weave scrims. The paper may be saturated, barrier coated, pre-sized, backsized, untreated, or fiber-reinforced. The paper can be provided as laminates with a different type of backing material. The polymer film may be primed or unprimed. The cloth can be untreated, saturated, pre-sized, backsized, porous, or sealed, and they may be woven or stitch bonded. The cloth may include fibers or yams of cotton, polyester, rayon, silk, nylon, or blends thereof. The cloth may be provided as laminates with different backing materials described herein. The nonwovens may include scrims and laminates to different backing materials mentioned herein. The nonwovens may include cellulosic fibers, synthetic fibers, or blends thereof. The abrasive sheet backing 110 may be a stem web used alone or incorporating the nonwoven, or as a laminate with a different type of backing. The looped fabric may include brushed nylon, brushed polyester, polyester stitched loop, and loop material laminated to a different type of backing material. The foam backing may include natural sponge material or polyurethane foam and the like.

The abrasive sheet backing 110 may have a basis weight in the range from 25 grams per square meter (g/m ² ) to 300 g/m ² or more. In some embodiments, the abrasive sheet backing 110 may be treated with a presize, backsize, and/or saturant coating in accordance with conventional practices.

The abrasive article 100 further includes an abrasive layer 120. The abrasive layer 120 is disposed on a portion 124 of the first major surface 112 of the abrasive sheet backing 110.

The abrasive layer 120 includes a plurality of abrasive particles 122. In some embodiments, the abrasive sheet backing 110 at least partially receives the abrasive layer 120 thereon.

The plurality of abrasive particles 122 may include any suitable abrasive material or combination of materials having abrading capabilities. In some embodiments, the plurality of abrasive particles 122 may include at least one material having a Mohs hardness of at least about 8, at least about 9, or at least about 10. Examples of such materials include fused aluminum oxide, heat treated aluminum oxide, white fused aluminum oxide, black silicon carbide, green silicon carbide, titanium diboride, boron carbide, tungsten carbide, titanium carbide, diamond, silica, iron oxide, chromia, ceria, zirconia, titania, silicates, tin oxide, cubic boron nitride, garnet, fused alumina zirconia, sol gel abrasive particles, combinations of these, and the like.

In some embodiments, the plurality of abrasive particles 122 may be present in any suitable size(s) and shape(s). For example, with respect to size, the plurality of abrasive particles 122 may have an average size in the range from about 0.1 micrometers to 2500 micrometers. The plurality of abrasive particles 122 may also have any shape suitable for carrying out abrading operations. Examples of such shapes include rods, triangles, pyramids, cones, solid spheres, hollow spheres, combinations of these, and the like. The plurality of abrasive particles 122 may be present in substantially non-agglomerated form or, alternatively, may be in the form of abrasive agglomerates in which individual particles are adhered together.

In some embodiments, the abrasive layer 120 further includes a bond system 140. In some embodiments, the plurality of abrasive particles 122 is distributed in the bond system 140.

The bond system 140 includes a make coat 142, such that the plurality of abrasive particles 122 adheres to the abrasive sheet backing 110. In other words, the make coat 142 helps to adhere the plurality of abrasive particles 122 to the abrasive sheet backing 110. In some embodiments, the make coat 142 includes a binder. The binder may be an organic, polymeric binder, and is derived from a binder precursor.

In some embodiments, the bond system 140 further includes a size coat 144 to reinforce the abrasive layer 120. Specifically, the size coat 144 is applied over the make coat 142 and the plurality of abrasive particles 122 in order to reinforce the plurality of abrasive particles 122. In some embodiments, the size coat 144 includes a binder. The binder may be an organic, polymeric binder, and is derived from a binder precursor.

The abrasive article 100 further includes a supersize coating composition 130 disposed on a portion of the abrasive layer 120 and not on the remaining portion 126 of the first major surface 112 of the abrasive sheet backing 110. In some embodiments, the supersize coating composition 130 has a substantially uniform thickness. In other words, the supersize coating composition 130 is substantially evenly distributed on the portion of the abrasive layer 120 and does not segregate into patterns that may be expected due to wicking of the supersize coating composition 130 around the plurality of abrasive particles 122.

In some embodiments, the supersize coating composition 130 includes at least one metal salt of a fatty acid. In some embodiments, the supersize coating composition 130 includes at least one of zinc stearate and calcium stearate. The metal salts of the fatty acid may function as an anti -loading agent and a binder component.

The supersize coating composition 130 may be included over the size coat 144 in order to prevent or reduce accumulation of swarf (a material abraded from a workpiece) among the plurality of abrasive particles 122 during abrading operations. The accumulation of swarf may otherwise dramatically reduce a cutting ability of the abrasive article 100 over time. In some embodiments, the supersize coating composition 130 may also be included over the size coat 144 in order to incorporate grinding aids into the abrasive article 100. Some examples of classes of the grinding aids include waxes, organic halide compounds, halide salts, metals, and alloys of metals.

In some embodiments, the plurality of abrasive particles 122 may include a surface coating to enhance the abrading performance of the abrasive particles 122 in accordance with conventional practices. In some instances, the surface coating may include a material, such as a silane coupling agent, that increases adhesion between the plurality of abrasive particles 122 and at least one of the make coat 142, the size coat 144, and the supersize coating composition 130.

FIG. 2 illustrates a flowchart for a method 200 of forming the abrasive article 100 shown in FIG. 1, according to an embodiment of the present disclosure. FIGS. 3A-3F illustrate schematic diagrams depicting various steps of the method 200 of forming the abrasive article 100 shown in FIG. 1, according to an embodiment of the present disclosure.

Referring to FIGS. 2 and 3A, at step 232, the method 200 includes providing an abrasive sheet 210. The abrasive sheet 210 includes the abrasive sheet backing 110 including the first major surface 112 and the second major surface 114. The abrasive sheet 210 further includes the abrasive layer 120 including the plurality of abrasive particles 122. The abrasive layer 120 is disposed on at least the portion 124 of the first major surface 112 of the abrasive sheet backing 110.

Referring to FIGS. 2 and 3B, at step 234, the method 200 includes providing a transfer film 220. The transfer film 220 includes a transfer film backing 222. In some embodiments, the transfer film backing 222 includes a polypropylene film. In some embodiments, the transfer film backing 222 includes a crosslinked thermoset polymer.

The transfer film 220 further includes the supersize coating composition 130 disposed on the transfer film backing 222. The supersize coating composition 130 is in solid-state. Since the supersize coating composition 130 is in solid-state, there may be no requirement of surfactants, that are otherwise required to suspend stearate-based compositions of the supersize coating composition.

In some embodiments, the transfer film backing 222 includes an array of wells 224A (shown in FIG. 5A) at least partially receiving the supersize coating composition 130 therein. In some embodiments, the array of wells 224A is a microreplicated array of wells. The array of wells 224A may aid in containing the supersize coating composition 130 and may allow higher coating weights to be applied. The array of wells 224A may be particularly useful as the supersize coating composition 130 may not form durable fdms when coated onto smooth surfaces (e.g., a surface of the transfer fdm backing 222). Therefore, the array of wells 224A may provide required stability to the supersize coating composition 130.

In some embodiments, the transfer film backing 222 includes a plurality of microstructures 224B (shown in FIG. 5B) extending from the the transfer film backing 222. The supersize coating composition 130 is at least partially disposed on the plurality of microstructures 224B. In some embodiments, the plurality of microstructures 224B is microreplicated. The plurality of microstructures 224B may aid in containing the supersize coating composition 130 and may allow higher coating weights to be applied. The plurality of microstructures 224B may be particularly useful as the supersize coating composition 130 may not form durable films when coated onto the smooth surfaces. Therefore, the plurality of microstructures 224B may provide required stability to the supersize coating composition 130.

In some embodiments, the plurality of microstructures 224B includes a plurality of projections. The plurality of projections may include a plurality of protrusions, a plurality of posts, and/or a plurality of spikes. In the illustrated embodiment of FIG. 4, the plurality of microstructures 224B are cuboidal in shape. However, the plurality of microstructures 224B may be of any shape as per desired application attributes. For example, the plurality of microstructures 224B may be cylindrical in shape and/or conical in shape.

In some embodiments, the method 200 further includes applying the supersize coating composition 130 to the transfer fdm backing 222 in liquid-state to form the transfer fdm 220 prior to providing the transfer fdm 220 to form the abrasive article 100. In some embodiments, the supersize coating composition 130 may be applied to the transfer fdm backing 222 via any suitable coating processes, such as die coating, roll coating, or spray coating. In these processes, the supersize coating composition 130 may be applied as a liquid suspension/solution.

In some embodiments, the method 200 further includes drying the supersize coating composition 130 in liquid-state, such that the supersize coating composition 130 is in solid-state. However, in some other embodiments, the supersize coating composition 130 may be applied to the transfer fdm backing 222 in solid-state. In still other embodiments, the supersize coating composition 130 can be partially dried after application to the transfer fdm backing 222.

Referring to FIGS. 2 and 3C, at step 236, the method 200 includes placing the transfer fdm 220 on the abrasive sheet 210, such that the supersize coating composition 130 contacts at least a portion of the abrasive layer 120. In some embodiments, the transfer film backing 222 includes an elastomeric material. In some embodiments, the elastomeric material may enable transfer film 220 to better conform to at least the abrasive layer 120. In some embodiments, the transfer film 220 may be contacted with the abrasive sheet 210 in a heat roll nip. In some embodiments, the transfer film 220 and the abrasive sheet 210 may be co-winded into a single roll.

As the supersize coating composition 130 is in solid-state, the supersize coating composition 130 may not infiltrate (e.g., due to wicking around the plurality of abrasive particles 122) into the abrasive layer 120 to contact the underlying layers (such as, the abrasive sheet 210) at the time of coating. Therefore, in some embodiments, the supersize coating composition 130 has the substantially uniform thickness. In other words, the supersize coating composition 130 is substantially evenly distributed on the portion of the abrasive layer 120 and does not segregate into patterns that may be expected due to wicking of the supersize coating composition 130 around the plurality of abrasive particles 122.

Referring to FIGS. 2 and 3D, at step 238, the method 200 includes applying heat and/or pressure 225 on at least one of the second major surface 114 of the abrasive sheet backing 110 and the transfer fdm backing 222 to transfer the supersize coating composition 130 to the abrasive sheet 210, such that the supersize coating composition 130 is disposed at least partially on the abrasive layer 120. Specifically, the method 200 includes applying heat and/or pressure 225 on at least one of the second major surface 114 of the abrasive sheet backing 110 and a surface of the transfer film backing 222 opposite to the supersize coating composition 130 to transfer the supersize coating composition 130 to the abrasive sheet 210, such that the supersize coating composition 130 is disposed at least partially on the abrasive layer 120. In some embodiments, a melt temperature of the transfer film backing 222 is greater than about 100 degrees Celsius (°C). In some embodiments, the melt temperature of the transfer film backing 222 is greater than about 105 °C, greater than about 110 °C, greater than about 115 °C, greater than about 120 °C, greater than about 125 °C, greater than about 130 °C, greater than about 135 °C, greater than about 140 °C, greater than about 145 °C, or greater than about 150 °C. In still other embodiments, the transfer film 220 may be placed in close proximity to the abrasive sheet 210 and an oscillating pressure may be applied to the surface of the transfer film backing 222 opposite to the supersize coating composition 130 in order to effect transfer of the supersize coating composition 130 to the abrasive sheet 210.

In some embodiments, the transfer film backing 222 may be more mechanically robust than conventional commercially available backings. In some embodiments, the transfer film backing 222 may be more heat and/or pressure tolerant than the conventional commercially available backings. In some embodiments, the transfer film backing 222 may be more mechanically robust than the abrasive sheet backing 110. In some embodiments, the transfer film backing 222 may be more heat and/or pressure tolerant than the abrasive sheet backing 110. In the illustrated embodiment of FIG. 3D, applying the heat and/or pressure 225 on at least one of the second major surface 114 of the abrasive sheet backing 110 and the transfer fdm backing 222 of the transfer film 220 includes applying the heat and/or pressure 225 on each of the second major surface 114 of the abrasive sheet backing 110 and the transfer film backing 222 of the transfer film 220 to transfer the supersize coating composition 130 to the abrasive sheet 210. In some embodiments, temperature, pressure and dwell time of the heat and pressure 225 may be selected to ensure that at least some of the supersize coating composition 130 transfers to the abrasive sheet 210.

In some embodiments, the adhesion between the supersize coating composition 130 and the transfer film backing 222 is lower than the adhesion between the supersize coating composition 130 and the abrasive layer 120. Therefore, the supersize coating composition 130 may substantially transfer from the transfer film backing 222 to the abrasive layer 120.

In some embodiments, the adhesion between the supersize coating composition 130 and the abrasive layer 120 is greater than the adhesion between the supersize coating composition 130 and the abrasive sheet backing 110. Further, in some embodiments, the adhesion between the supersize coating composition 130 and the transfer film backing 222 is greater than the adhesion between the supersize coating composition 130 and the abrasive sheet backing 110. Therefore, the supersize coating composition 130 may substantially transfer to the abrasive layer 120 and may not substantially transfer to the abrasive sheet backing 110.

Since the supersize coating composition 130 is in solid-state, it may be applied to one or more desired locations of the abrasive sheet 210 in a controlled manner. For example, it may be desirable to apply the supersize coating composition 130 on the portion of the abrasive layer 120 and not on the remaining portion 126 of the first major surface 112 of the abrasive sheet backing 110. This is because application of the supersize coating composition 130 on the remaining portion 126 of the first major surface 112 of the abrasive sheet backing 110 may negatively impact the abrasive sheet backing 110 and may also lead to wastage of the supersize coating composition 130 and thereby may increase manufacturing costs.

Referring to FIGS. 2 and 3E, at step 240, the method 200 includes removing the transfer film backing 222 from the supersize coating composition 130. In some embodiments, removing the transfer film backing 222 from the supersize coating composition 130 may include unwinding the roll to remove the transfer film backing 222. Since the supersize coating composition 130 is in solid-state, the method 200 of forming the abrasive article 100 shown in FIG. 1 may prevent the foam formation.

Referring to FIG. 3F, in some embodiments, the method 200 (shown in FIG. 2) further includes applying heat 227 on at least one of the second major surface 114 and the supersize coating composition 130 after removing the transfer film backing 222. In the illustrated embodiment of FIG. 3F, applying the heat 227 on at least one of the second major surface 114 and the supersize coating composition 130 includes applying the heat 227 on each of the second major surface 114 and the supersize coating composition 130 after removing the transfer film backing 222.

In some embodiments, applying the heat 227 on at least one of the second major surface 114 and the supersize coating composition 130 after removing the transfer film backing 222 may melt the supersize coating composition 130 and form a clear layer. This may improve an appearance of the abrasive article 100. During conventional liquid-based coating processes, the heat 227 is required to both evaporate a supersize coating in liquid-state as well as raise the temperature of the supersize coating above its melting temperature. As the method 200 includes transfer of the supersize coating composition 130 in solid-state, the evaporation of the supersize coating composition 130 is not required. This may reduce evaporation costs in terms of equipment costs and/or energy costs, as well as reduce manufacturing time.

Example

The present disclosure is further described with reference to the following example that explain exemplary preparation of the abrasive article 100 shown in FIG. 1. The example will be explained in reference to FIGS. 1 to 3A-3F.

The following example is merely meant to exemplify the present disclosure, but is not intended to limit or otherwise define the scope of the present disclosure.

The transfer film 220 was prepared using the supersize coating composition 130. The supersize coating composition 130 included a zinc stearate dispersion having a trade designation “EC1428” and being commercially available from eChem Ltd. The supersize coating composition 130 was applied to a surface of the transfer film backing 222. The transfer film backing 222 included a polypropylene film including the microreplicated array of wells 224A (shown in FIG. 5A). The array of wells 224A was formed by a set of perpendicularly intersecting walls having a height of about 75 micrometers and a pitch of about 125 micrometers. The wells of the array of wells 224A were subdivided by a set of intersecting walls having a height of about 3 to 5 micrometers and a pitch of about 10 micrometers. The supersize coating composition 130 was applied using a 3M Performance Spray Gun with a 1.3 millimeter (mm) nozzle held at a distance of about 8 inches. After spraying a film of the supersize coating composition 130 for 18 passes the film was dried using a heat gun to drive off water. This resulted in the transfer film 220 including the supersize coating composition 130 in solid-state. The supersize coating composition 130 had a weight of about 70 grams per square meter (gsm).

A portion of the transfer film 220 was positioned, such that it contacted roughly one half of the abrasive sheet 210. The abrasive sheet 210 used has a trade designation “3M™ 710W Xtract™ Cubitron ™ II Net Sheet”, grade P80, and is commercially available from 3M, St. Paul, Minnesota. This construction was placed into a lab press at about 280 degrees Fahrenheit (°F) for about 30 seconds under an applied load of about 700 pound per square inch (psi). The construction was removed from the lab press and the transfer film 220 was immediately separated from the abrasive sheet 210 to obtain an Example Abrasive. By comparing weights of the abrasive sheet 210 before and after the transfer process, the weight of the supersize coating composition 130 was estimated to be 26 gsm.

FIG. 4 is a photomicrograph of the Example Abrasive having one half of the abrasive sheet 210 that was in contact with the transfer film 220 (shown in FIG. 3B) to form the abrasive article 100 and the other half of the abrasive sheet 210 that was not in contact with the transfer film 220. A demarcation 250 shows a separation between the abrasive article 100 and the other half of the abrasive sheet 210 that was not in contact with the transfer film 220.

FIG. 5A is a photomicrograph of a segment of the transfer film 220 after being separated from the abrasive sheet 210 (shown in FIG. 3C), according to an embodiment of the present disclosure.

As is apparent from FIG. 5A, the transfer film backing 222 of the transfer film 220 included the array of wells 224A. Further, the array of wells 224A of the transfer film backing 222 was distorted after the transfer process. Moreover, some portion of the supersize coating composition 130 did not transfer to the abrasive sheet 210.

To evaluate an abrading performance of the abrasive article 100, a thin layer of a body filler was applied to a painted metal surface. The body filler used has a trade designation “Platinum Plus Lightweight Filler” and is commercially available from 3M, St. Paul, Minnesota. After allowing the body filler to cure at room temperature for 10 minutes and 45 seconds, the Example Abrasive was hand sanded on the body filler for about 30 seconds. This sanding was conducted such that both the abrasive article 100 and the other half of the abrasive sheet 210 that was not in contact with the transfer film 220 were sanded on the body filler at the same time. Upon completion of the sanding interval, an attempt was made to remove any loading or swarf.

FIG. 6 is a photograph of the Example Abrasive after the attempt to remove the loading from the Example Abrasive. As is apparent from FIG. 6, the one half of the abrasive sheet 210 that was in contact with the transfer film 220 (shown in FIG. 3B) to form the abrasive article 100 had lesser loading in comparison to the other half of the abrasive sheet 210 that was not in contact with the transfer film 220.

In the present detailed description of the preferred embodiments, reference is made to the accompanying drawings, which illustrate specific embodiments in which the invention may be practiced. The illustrated embodiments are not intended to be exhaustive of all embodiments according to the invention. It is to be understood that other embodiments may be utilized, and structural or logical changes may be made without departing from the scope of the present invention. The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims.

Unless otherwise indicated, all numbers expressing feature sizes, amounts, and physical properties used in the specification and claims are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the foregoing specification and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by those skilled in the art utilizing the teachings disclosed herein.

As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” encompass embodiments having plural referents, unless the content clearly dictates otherwise. As used in this specification and the appended claims, the term “or” is generally employed in its sense including “and/or” unless the content clearly dictates otherwise.

Spatially related terms, including but not limited to, “proximate,” “distal,” “lower,” “upper,” “beneath,” “below,” “above,” and “on top,” if used herein, are utilized for ease of description to describe spatial relationships of an element(s) to another. Such spatially related terms encompass different orientations of the device in use or operation in addition to the particular orientations depicted in the figures and described herein. For example, if an object depicted in the figures is turned over or flipped over, portions previously described as below or beneath other elements would then be above or on top of those other elements.

As used herein, when an element, component, or layer for example is described as forming a “coincident interface” with, or being “on,” “connected to,” “coupled with,” “stacked on” or “in contact with” another element, component, or layer, it can be directly on, directly connected to, directly coupled with, directly stacked on, in direct contact with, or intervening elements, components or layers may be on, connected, coupled or in contact with the particular element, component, or layer, for example. When an element, component, or layer for example is referred to as being “directly on,” “directly connected to,” “directly coupled with,” or “directly in contact with” another element, there are no intervening elements, components, or layers for example.

Various examples have been described. These and other examples are within the scope of the following claims.