CN113386058A

CN113386058A - Abrasive article and method of making such article

Info

Publication number: CN113386058A
Application number: CN202010170947.2A
Authority: CN
Inventors: 桑德罗·乔瓦尼·朱塞佩·费罗纳托
Original assignee: KGS Diamond Guangzhou Co Ltd
Current assignee: KGS Diamond Guangzhou Co Ltd
Priority date: 2020-03-12
Filing date: 2020-03-12
Publication date: 2021-09-14

Abstract

A method for making an abrasive article (10), comprising: providing a base sheet comprising a support layer (12), and a fastening member (20) of a quick release system QRS (18, 19); applying a metal coating (36) to the support layer and the QRS member; abrasive particles (38) are applied to at least a portion of the first surface of the support layer such that the particles are thermally coupled to the metal coating. The support layer defines a plurality of openings (26) extending therethrough from a first surface (14) of the support layer to a second surface (16) of the support layer opposite the first surface and allowing passage of abrasive dust. The QRS member is secured on or in the support layer and protrudes from the second surface and is configured to secure the article to a surface of a complementary fastening member (19) comprising the QRS. The metallic coating covers both the support layer and the QRS member and forms a thermally conductive path from the abrasive particles on the first surface to the QRS member on the second surface via the openings.

Description

Abrasive article and method of making such article

Technical Field

The present invention relates to abrasive articles, including articles for use in abrading or polishing processes of objects. Furthermore, the present invention relates to a method for manufacturing such an abrasive article.

Background

Abrasive articles are well known and may be used in a variety of surface treatment operations. Such operations may include grinding, leveling, polishing, etc. of relatively hard materials like stone (e.g., granite, marble), glass, ceramic (tungsten carbide), concrete, solid metals (e.g., aluminum, titanium, steel) and composites thereof, or fiberglass reinforced plastics and hard coatings. Alternatively, such surface treatment operations may be carried out on materials with a lower hardness (resistance to abrasion), such as paints or varnishes, intended to polish or totally remove a layer of such material. Depending on the product to be treated, the abrasive article may be applied in the form of, for example, a belt, a disc, or a sheet.

Such abrasive articles may be used in conjunction with a sanding tool that includes a backup pad to which the abrasive article may be temporarily attached using a Quick Release System (QRS), which may be, for example, a touch fastener (e.g., hook-and-loop attachment, also known as Velcro (Velcro)). Thus, the abrading tool can be reused while only the abrasive article needs to be replaced when the article is damaged or worn, or when an abrasive article having a different treatment effect is desired.

Patent document US2007/0028525a1 describes a known abrasive article comprising a porous mesh support layer having holes to allow passage of air and dust particles and hooks (hook) for attachment with a backup pad of a loop-equipped abrading tool. However, such known articles tend to overheat during use, which results in a high probability of generating burn marks on the surface of the treated object when the article is used for an extended period of time.

It is desirable to provide an abrasive article with a QRS that can withstand higher mechanical and thermal loads.

Disclosure of Invention

Thus, according to a first aspect of the invention, there is provided a method for making an abrasive article, the method comprising:

-providing a base sheet comprising a support layer and a fastening member of a QRS;

-applying an electrically and thermally conductive coating onto both the support layer and the fastening member; and

-applying abrasive particles onto at least a portion of the first surface of the support layer such that the abrasive particles are thermally connected with the coating.

In this method, the support layer defines a plurality of openings extending through the support layer from a first surface of the support layer to a second surface of the support layer opposite the first surface. The support layer is configured to allow abrasive dust (abrasion dust) to pass through the support layer. The fastening member is secured on or in the support layer and protrudes from the second surface of the support layer and is configured to temporarily secure the abrasive article to a surface of a complementary fastening member comprising a QRS. The coating is applied such that the coating (when in a solid phase) covers both the support layer and the fastening members and forms a thermally conductive path from the abrasive particles on the first surface to the fastening members on the second surface of the support layer via the openings. The coating may consist of any metal, metal alloy or metal-like substance which can be deposited by electrodeposition techniques from a suitable bath (bath) to form a solid phase coating completely covering the support layer and the fastening member and which is wear resistant, resistant to high operating temperatures and a good heat conductor. Preferably, the coating has a melting temperature of at least 200 ℃ (at atmospheric pressure), a thermal conductivity of at least 40 watts/meter kelvin, and a vickers hardness of at least 350 MPa, or preferably, above 500MPa (in solid form and at operating temperature).

The resulting abrasive article has improved heat dissipation properties. The coating is formed as a continuous body onto the exposed outer surfaces of both the support layer and the fastening members to form an uninterrupted thermal conduction path that allows excess heat, generated in the deposition of abrasive particles on the first surface during abrasive action, to be quickly conducted not only through the coating to the sides, but also through the coating, along and through the openings, and to the fastening members of the second surface of the support layer. Air or other fluid cooling medium may also be circulated through the openings to allow heat stored in the coating to be absorbed and carried away from the abrasive particles. For this purpose, the article-carrying abrading tool may be equipped with a circulation system and holes for circulating a cooling medium through openings of the abrasive article. The effective heat dissipation area of the coating is considerable, since the coating extends across both the support layer and the fastening member. The improved heat dissipation through the coating (through conductive and convective heat transfer) makes the article less prone to overheating during use, thereby reducing the likelihood of damage to the abrasive article or the object being treated during abrasive action, and/or reducing the duration or frequency of cooling interruptions. In addition, the coating may improve the mechanical strength of the abrasive article as it provides additional tear strength on the support layer.

The term "Quick Release System (QRS)" as used herein refers to a plurality of cooperating fastening members, including a first fastening member and a second fastening member, the first fastening member being densely distributed across a surface of a first object and the second fastening member being densely distributed across a complementary surface of a second object. At least one of these objects is flexible in dimensions to allow out-of-plane bending or folding. Once engaged, the two fastening members interlock to temporarily secure the two objects to one another while allowing the two objects to be separated again by a pulling force. The QRS may be a touch fastener, such as a hook and loop fastener, the first surface carrying a plurality of monofilament members protruding therefrom shaped like hooks, and the complementary surface carrying a plurality of multifilament members woven into annular protrusions. Alternatively, the QRS may be a mushroom-loop fastener, where there is a monofilament protrusion with a mushroom-shaped head, rather than a hook-type fastening member. It will be appreciated that the choice of the type of first component on the abrasive article will depend on the second component being provided on the back pad or mounting head of the sander. In this way, the back pad and mounting head are more likely to use either hook type fastening members or mushroom type fastening members, preferably, the abrasive article having the first element formed as a loop (loop). Alternatively, the back pad or mounting head may be provided with a loop-type fastener, and the abrasive element may be provided with a short strand (strand) carrying a hook or mushroom fastener at one distal end and secured to the support layer at the opposite distal end.

The opening in the support layer extends all the way through the support layer and is open on both the first and second surfaces of the support layer. These openings are arranged in a surface (i.e., two-dimensional) array across the support layer. The openings are sized to allow dust particles originating from the surface being sanded or wear of the abrasive article to be transported from the first surface, through the support layer, to the second surface. The openings may have various cross-sectional shapes, such as quadrilateral (e.g., rectangular, square, diamond, trapezoidal), elliptical (e.g., circular), or different polygonal (e.g., triangular, hexagonal, etc.). In the support mesh made of woven fibrous material, the openings may have a cross-sectional shape of a regular quadrilateral (e.g. regular diamond, rectangle, but preferably square). The characteristic cross-sectional dimension of the opening may be in the range of 0.1 mm to 4 mm. The spacing between the centers of immediately adjacent openings may be in the range of 0.77 millimeters to 2.25 millimeters.

In many embodiments, the open area (percentage) of the plurality of openings in the support layer is in a range of 20% to 60% of the total surface area of the abrasive article. An opening area percentage of the plurality of through openings in the indicated range achieves a good balance between the mechanical strength of the article on the one hand and the ability of the article to discharge heat and dust on the other hand.

The plurality of openings in the support layer may be formed in a regular (e.g., symmetrical) pattern along the surface. Such a pattern may exhibit two-dimensional periodicity, mirror symmetry, and/or discrete rotational symmetry. The term "discrete rotational symmetry" is used to indicate that the support layer exhibits symmetry when rotated through a non-zero angle of 180 ° or less about an axis perpendicular to the plane of the layer. Examples are a honeycomb pattern, a wire mesh with a plurality of diamond shaped openings, or a wire mesh with a plurality of square shaped openings. The pattern may be a cellular pattern in which a single cell shape is repeated along one or both surface dimensions, but the pattern may also be tessellated, in which rotational symmetry is assumed only once for a group of multiple cells. Having a periodic surface pattern allows the abrasive article to be produced on a stick, after which the abrasive article can be cut to any desired shape. A woven square mesh is preferred because it is inexpensive to manufacture and is symmetrical under a 90 deg. rotation.

In one embodiment, the fastening member is secured directly on or in the support layer prior to application of the coating. Then, the method may further include:

-applying a coating to cover and extend in a continuous manner across the exposed outer surfaces of both the support layer and the fastening member.

The support layer and the fastening member are formed into an integrated body (i.e., unitary body), and then the coating layer is simultaneously applied to the integrated body. In this context, "integrated" refers to a rigid attachment of the fastening members to the support layer such that their combined exposed surface area is less than the sum of the respective exposed surface areas of the support layer and the fastening members prior to integration. In contrast to a support layer and a fastening member (with its own backing layer, e.g. a mesh or glue film) which are coated separately before being attached to each other, integrating the support layer and the fastening member before applying the coating results in a significant reduction of the total outer surface of the support layer and the member which needs to be coated. The simultaneous coating of the integrated layer with the fastening member reduces the time required for coating and the amount of coating material required, resulting in a more efficient and/or economical manufacturing process.

The coating may also strengthen the mechanical connection between the fastening member and the support layer. Alternatively or additionally, for a mesh having separate interwoven strands (the strands are not initially secured to each other), the coating may help to secure the strands of the mesh in place.

The support layer and the fastening member may be integrally formed as a single piece. The term "integrally formed" herein means that the support layer and the fastening member are manufactured simultaneously as one unit, rather than as separate pieces that are subsequently mechanically attached, welded, bonded, or otherwise integrated. For example, a plastic screen with hooks or mushroom-shaped fastening members integrated on the lower surface may be integrally formed using a casting technique, a 3D printing technique, or injection molding.

In many embodiments, the coating forms a base layer. Then, the method may further include:

-applying a coating onto the support layer and the fastening member using electrolyte co-deposition, such that the abrasive particles are embedded in the portion of the coating present at the first surface of the support layer.

Electroplating (also called galvanic deposition) is a process whereby metal cations dissolved in a liquid medium are deposited as a thin layer on the surface of an object used as an electrode by an applied electric field. Electrolyte co-deposition is an electroplating method by which non-metallic particles (in this case, abrasive particles) are embedded in a metallic coating that forms the matrix and is obtained from a solution in which metal cations are dissolved and particles are suspended.

Preferably, the thickness of the finished electroplated coating comprising abrasive particles is in the range of 4 to 300 microns, the thickness depending on the particle size (grit size) of the particles.

In various embodiments, the method further comprises:

-applying an electrically conductive primer layer directly onto the support layer and the fastening member before applying the coating; and

-applying a coating onto the base coat using electroplating or electrolytic co-deposition.

The primer layer may be a metallic primer layer applied directly to the support layer and the fastening member, for example using electroless plating, to form a solid continuous metallic layer encapsulating the support layer.

"electroless plating" (also referred to as "electroless plating" or "autocatalytic plating") involves a chemical reaction of metal cations in an aqueous solution without the use of an electric field. The resulting metallic primer coating, which is thin relative to the electroplated metallic coating, imparts electrical conductivity to the coated outer surfaces of the support layer and fastening member, facilitating subsequent steps of coating the article with a (thicker) metallic layer using electroplating techniques. Conductance of applied solid phase primerA ratio of at least 10⁵Siemens per meter and, preferably, the base coat has a melting temperature (at atmospheric pressure) of at least 150 ℃. The primer layer may be any conductive metal or metal alloy that can be applied to the support layer and the fastening member by electroless plating, such as copper, gold or silver (possibly alloyed with other minor components), but is preferably nickel (an alloy). Preferably, the thickness of the undercoat layer formed by electroless plating of nickel is in the range of 0.05 to 8 micrometers. Alternatively, the primer layer may be of conductivity of at least 10⁵A non-metallic material having S/m and a melting temperature of at least 150 ℃.

In various embodiments, the method may further comprise:

-providing a base sheet shaped to be stored in a roll or a folded stack of elongated fabrics;

-unwinding or opening consecutive fabric portions of substrate sheet from said roll or folded stack continuously or intermittently;

-continuously or intermittently applying a coating layer onto both the support layer and the fastening members, and continuously or intermittently applying abrasive particles onto the first surface of the support layer of respective consecutive fabric portions that have been unrolled or opened, thereby forming fabric portions of the semi-finished abrasive sheet; and

-cutting a predetermined shape from at least one fabric portion of the semi-finished abrasive sheet to form an abrasive article.

Thus, a flexible semi-finished abrasive sheet (comprising a substrate with a coated support layer and QRS fastening members, and carrying a deposit with abrasive particles) can be conveniently produced in a roll-to-roll manner and subsequently cut (e.g., punched) into an abrasive article.

In various embodiments, the abrasive article may be formed as a pad, disc, sheet, or belt configured to perform an abrading and/or polishing process.

According to a second aspect of the present invention, and according to the advantages and effects described herein above with reference to the first aspect, there is provided an abrasive article for treating a surface. Abrasive articles include substrates, coatings, and deposits of abrasive particles. The base sheet comprises a support layer and a QRS fastening member. The support layer defines a plurality of openings extending through the support layer from a first surface of the support layer to a second surface of the support layer opposite the first surface. The openings are configured to allow abrasive dust to pass through the support layer. The fastening member is secured on or in the support layer and protrudes from the second surface of the support layer and is configured to temporarily secure the abrasive article to a surface of a complementary fastening member comprising a QRS. Abrasive particles cover at least a portion of the first surface of the support layer and are thermally coupled to the coating. The coating covers both the support layer and the fastening members and forms a thermally conductive path from the abrasive particles on the first surface to the fastening members on the second surface of the support layer via the openings.

In one embodiment, the support layer is a mesh formed of a plurality of filaments (wires) or a plurality of strands that cross or intersect one another and define a plurality of openings therebetween.

The term "web" as used herein refers to a network of interconnected strands/filaments that form a two-dimensional surface structure in a mechanically resting state. These threads/strands may be formed from a plurality of fibers (e.g., continuous monofilaments), from a plurality of continuous yarns (i.e., intertwined fibers), or from a plurality of continuous strands (i.e., intertwined yarns or strands) made from such fibers. These strands/filaments extend periodically in a continuous manner along the surface of the web and are arranged in a periodic and structured orientation with respect to each other. Herein, the mesh forms an "open mesh" in which the strands/filaments are patterned in a spaced apart arrangement such that the strands/filaments are spaced apart by a non-zero distance and enclose through-holes between them. The thickness dimension of the mesh surface structure is at least three orders of magnitude smaller than its two in-plane dimensions. In particular, typical cross-sectional dimensions of the fibers of the web may be in the range of 0.05 mm to 1.5 mm, and the thickness of the web in the out-of-plane direction may be in the range of 0.1 mm to several mm.

The filaments or strands of the mesh may be braided, welded, integrally formed, slit expanded, or the like. For example, the mesh may be a wire mesh formed of first strands extending in a first in-plane direction and second strands extending in a second in-plane direction, the second strands intersecting or intersecting the first strands. For example, the mesh may be a regular two-dimensional quadrilateral mesh of first and second strands or yarns interwoven with one another.

In various embodiments, the web is flexible to out-of-plane folding/bending deformations. The term "flexible" herein means that the web is sufficiently soft to allow out-of-plane buckling (e.g. bending or folding) to enable buckling by manual force from a resting planar state to a temporary curved shape of the order of a radius of curvature of a centimeter or even possibly a millimeter, without breaking. This flexibility simplifies the attachment and removal of the article from the base pad of the abrading tool and allows the article to be produced and stored on a roll or folded stack. Additionally, the mesh may have low elasticity (i.e., low bending stiffness) so that the temporary bent/folded shape does not cause significant internal restoring forces (as compared to the manual force applied to fold/bend the mesh) that urge the layer back to its planar state.

Preferably, the mesh is made of continuous monofilaments/ropes/yarns of synthetic (e.g. polymer, mineral, glass or ceramic) fibres, which have a high heat resistance (a burning/melting/decomposition temperature of at least 160 ℃) and are easy and reversibly flexible to bend or fold out of plane, and also have a high ultimate tensile strength (at least 100MPa) along its length. Applying one or more coatings to such a web imparts considerable heat dissipation capacity on the article and ensures sufficient flexibility. For example, the mesh may be composed of strands made of polyester fibers. The polyester is resistant to most chemicals, which allows the screen to be placed in a chemical solution to apply the above-mentioned electroless plating technique or plating technique without damaging the screen. In addition, polyesters have a typical melting temperature of about 250 ℃, which is convenient during manufacture of the article as well as during use.

In various embodiments, the mesh is a woven, knit, or knit fabric. Thus, the fastening member can be easily integrated into the screen. A weave, weave or knit pattern may be used in which loops or hooks naturally protrude from the bottom surface of the wire mesh. The hooks may be formed by using split threads or by cutting the loop in two parts. The coating fixes the position of all yarns in the screen relative to each other and the position of the fastening members relative to the screen. A woven, knitted or braided web material may be supplied on a roll, which may be usefully applied in roll-to-roll manufacturing processes for abrasive articles.

In various embodiments, the web is an extruded web, a punched web, or a web of slit-expanded material. The first surface of these types of webs (carrying the abrasive article) can be made substantially flat, which helps to enlarge the contact area between the article and the surface to be polished, and thus results in smoother polishing results and more uniform wear of the article during use.

In various embodiments, the fastening members are integrated with the strands of the mesh such that the fastening members and the strands engage along the contact surface, and such that the coating covers both the mesh and the fastening members and extends across both the mesh and the fastening members in a continuous manner without extending directly between the fastening members and the strands along the contact surface.

In an embodiment, the fastening member is formed by a monofilament having a base which is mechanically fixed to the support layer or incorporated into the support layer. For example, the bases may be embedded in the strands of the mesh support layer, or may be intertwined with the strands of the mesh.

Relying on mechanical fixation of the fastening members to the support layer avoids the need for adhesives or other bonding agents to attach the fastening members to the support layer. When electroplating is used to apply the metal coating, or when electroless plating is used to apply the metal primer, the mechanical bond is not affected by the chemical solution with the metal cations (as opposed to the adhesive bond) and does not contaminate the chemical solution by dissolving the adhesive. Furthermore, the binders used in the art typically have a high electrical resistivity, which can impede the flow of the desired charged particles during electroplating and thus can frustrate the deposition of metal.

The expression "intertwining with the mesh" refers herein to the results obtained by any technique known from textile processes (for example weaving, knitting, spinning, braiding, interlacing, or other processes of intertwining QRS filaments with the strands of a mesh).

The abrasive article can be formed as a rotationally symmetric pad, such as a circular pad, and wherein both the support layer and the openings have discrete rotational symmetries.

Abrasive articles with rotationally symmetric webs are well suited for application on abrading tools having an actuating head that rotates about a nominal axis perpendicular to the surface normal of the article and on which the article is centered.

The coating may be, for example, a metal coating consisting essentially of nickel or a nickel-based alloy. Nickel can be deposited in a uniform manner, is corrosion resistant and has a high hardness and wear resistance, being resistant to mechanical wear by friction along its surface.

The abrasive particles may consist essentially of diamond or cubic boron nitride (c-BN). The use of diamond or c-BN as abrasive particles makes the abrasive particles suitable for use in grinding surfaces of comparable hardness, such as rock. The particle size of the abrasive particles can vary from >0 to 250 μm.

The abrasive particles can be selectively deposited in a non-uniform manner across the first surface of the support layer (in a characteristic proportion greater than each opening) to form a pattern having localized surface regions of the particles that are narrow and interspersed by surface regions devoid of abrasive particles. The shape of such surface patterns and the spacing between them may be varied to adjust the flexibility and/or abrasiveness (abrasive aggregation) of the article. The distribution of particle deposits may for example be due to (discrete or continuous) plane symmetry in the article for a grinding process involving (continuous or oscillatory) rotational motion, or to translational symmetry in the article for a grinding process involving (continuous or oscillatory) linear motion.

Drawings

Embodiments will now be described, by way of example only, with reference to the accompanying schematic drawings in which corresponding reference symbols indicate corresponding parts. In the drawings, like numbering represents like elements. Multiple instances of an element may each include a separate letter appended to the reference number. For example, two instances of a particular element 22 may be labeled "22 a" and "22 b". Reference numbers may be used without an additional letter (e.g., "22") to generally refer to a non-specific instance or all instances of that element, while reference numbers may include an additional letter (e.g., "22 a") to refer to a specific instance of an element.

FIG. 1 schematically illustrates a perspective view of an abrasive article according to an embodiment;

2a-b show a top view and a cross-sectional side view of the article from FIG. 1;

FIG. 3 schematically illustrates an embodiment of a system and process for making an abrasive article;

fig. 4a-c illustrate steps in a process for making an abrasive article according to one embodiment.

The drawings are intended for purposes of illustration only and are not intended to limit the scope or protection sought by the claims.

REFERENCE SIGNS LIST

10 abrasive article

12 support layer (e.g., wire mesh)

14 first surface

16 second surface

18 QRS layer

19 QRS layer with complementary Member

20 fastening member

22 warp yarns

24 weft

26 through opening

27 reduced opening

28 base

30 contact surface

32 (initially) exposed surface

34 base coat

36 deposit coating

38 abrasive particles

40 grinding tool

42 rotating base

50 manufacturing system

52 supply roll

53 (of the substrate) Fabric part

54 collecting roller

55 (of abrasive sheet) fabric portion

56 guide roller

58 Electrostatic roller

60 first plating bath

62 first liquid

64 second plating bath

66 a second liquid

X longitudinal direction

Y transverse direction

Z normal direction

Axis of rotation A

Detailed Description

The following is a description of some embodiments of the invention, given by way of example only and with reference to the accompanying drawings.

FIG. 1 schematically illustrates a perspective view of an abrasive article 10, with a portion having been schematically cut away, showing a portion of the article 10 in cross-section. The article 10 may be used to abrade surfaces made of glass, metal, stone, ceramic, or composites.

The article 10 includes a support layer 12 formed as a web, the support layer 12 defining an upper surface 14 and a lower surface 16 on opposite sides. The upper surface 14 carries a deposit with abrasive particles 38 and is adapted to face a surface of an object to be treated (e.g., ground, polished, etc.).

The article 10 is configured to be attached to a disc-shaped base pad 42 of the sanding tool 40 by means of the hook and

loop fastening systems

18 and 19. Such a base pad 42 may be rotatable about a nominal axis of rotation a relative to the rest of the abrading tool 40 (not shown). On the lower surface 16 of the mesh 12, the article 10 is provided with a first QRS layer 18 formed by densely distributed fastening members 20, the fastening members 20 protruding downwards from the lower surface 16. In this embodiment, the fastening member 20 is a collar configured to engage and interlock with hooks on the complementary QRS layer 19 having hooks on the base pad 42. In the attached state ready for operation, the disc-shaped item 10 is centered with respect to the nominal axis a.

Fig. 2a shows a top view of a portion of the abrasive article 10 from fig. 1 in more detail. The screen 12 is coated with a plurality of

layers

34 and 36. The article and layers are shown in a partially peeled manner for illustrative purposes only.

The screen 12 is flexible and is formed from warp yarns 22 and weft yarns 24, the warp yarns 22 and weft yarns 24 being woven together such that the warp yarns 22 and weft yarns 24 cross each other in an alternating overlapping manner. In this embodiment, the warp yarns 22 and weft yarns 24 are made of polyester fibers that have been coated with a phenolic resin (not shown). The warp yarns 22 and the weft yarns 24 each have a diameter of about 250 μm. It will be appreciated that different wire (tread) diameters may be used depending on the desired mechanical properties of the resulting article.

As shown in fig. 2a, the weave pattern forms through openings 26 in the mesh 12, the through openings 26 being enclosed between adjacent pairs of mesh strands 22 and 24 of the mesh. The surface area of each opening 26 is about 0.5mm². The open area (percentage) of the plurality of openings 26 relative to the total area of the bare mesh 12 is about 40%.

In this embodiment, the fastening member 20 is also made of polyester fiber yarn coated with phenolic resin. The resin-coated fiber filaments have a diameter of about 60 μm and are wound in the weave pattern of the wire mesh 12 to form loops. The length of the collar is on average about 5.5 mm.

The screen 12 and the intertwined fastening members 20 are covered with a metallic base coat 34, a metallic primary coat 36 (which covers and completely encapsulates the base coat 34), and deposits of abrasive particles 38 (which are embedded in the primary coat 36 present on the upper surface 14 of the article 10). The primary coating 36 secures (immobilizes) the warp yarns 22, weft yarns 24, and fastening members 20 relative to one another.

Fig. 2b shows a side cross-sectional view of a portion of the abrasive article 10 showing the deposits having abrasive particles 38 located primarily on the top surface 14 of the screen 12. In contrast, the metal coating 36 is distributed in a continuous manner across the outer surfaces of the web 12 and the fastening members 20.

In this embodiment, the thickness of the primer layer 34 is about 0.2 μm, and the thickness of the primary coating layer 36 is about 100 μm. Both the main coat 36 and the base coat 34 are made of nickel. It should be understood that a wide variety of other metals, metal alloys, or metal-like materials having high thermal and electrical conductivity may be used, and that the preferred thickness of the metallic coating 36 is related to the desired thermal conductivity of the selected metal. Preferably, the bulk thermal conductivity (bulk thermal conductivity) of the coating 36 is at least 40 watts per meter Kelvin.

The deposits having abrasive particles 38 are embedded in the main coat 36 on the upper surface of the screen 12. In this embodiment, the base coating 36 is made of nickel and the abrasive particles 38 are diamond particles having a median particle diameter of 40 μm. However, it is understood that in other embodiments, other matrix materials having high melting temperatures and high thermal conductivities and abrasive grains having different materials and/or grit sizes may be used depending on the intended use of the article.

Application of the

coatings

34 and 36 to the web 12 causes the openings 26 to become reduced-size openings 27. As a result, the surface area of each reduced opening 27 is about 0.3mm²And the reduced open area of the openings 27 is about 30% relative to the total area of the abrasive article 10. The size and amount of the openings 27 are still large enough to allow dust particles to pass through the article 10. Such dust particles may originate from the surface being processed of the object, for example, or from wear of the article 10 itself. In addition to removing dust, the openings 27 also allow for ventilation through the abrasive article 10.

The coating 34 and the coating 36 provide a thermally conductive path from the upper surface 14 of the article 10, through the opening 27, and to the fastening member 20 on the lower surface 16. During use of the article 10, heat generated by friction between the upper surface 14 with the abrasive particles 38 and the surface of the object being treated may be conducted along these paths, through the screen 12, and toward the fastening members 20. The sanding tool 40 may be equipped with a cooling device in the base 42 that extends along the surface with the QRS layer 19 and allows heat accumulated in the QRS layer 18 to be removed by conductive heat transfer.

Alternatively or additionally, heat accumulated in

layers

34 and 36 may be absorbed and dissipated by convective heat transfer, for example, by air circulating through openings 27 absorbing a portion of the heat in coating 36 and transferring the heat away from article 10. For this purpose, the abrading tool 40 may be equipped with an air suction system having suction holes (not shown in fig. 1) provided in the base 42 to facilitate the flow of air through the openings 26.

Fig. 3 illustrates a method and system 50 for manufacturing an abrasive article 10 according to various embodiments. An elongated web of precursor material of the web is stored on a supply roll 52 and continuously or intermittently unwound into successive web portions 53, the web portions 53 being supplied by guide rolls 56 towards a first bath 60 with an electroless plating solution 62. The resulting primed fabric portion is moved continuously or intermittently by the electrostatic roller 58 toward and into a second plating bath 64, the second plating bath 64 holding a second liquid 66, the nickel ions and abrasive particles 38 being present in the second liquid 66. In the channel 64, an electric field is applied between the coated fabric sections 53 and the source area of the abrasive particles so as to deposit nickel ions as a coating 36 onto both the support layer 12 and the fastening member 20, while the abrasive particles 38 are simultaneously embedded in the resulting coating 36 on the first surface of the support layer of the respective consecutive fabric sections 53. The resulting fabric portion 55 of the semi-finished abrasive sheet is removed from the second plating tank 64 and stored on the collection roll 54. The fabric portions 55 are then cut into separate abrasive articles 10.

Fig. 4a-4c illustrate further method steps for making the abrasive article 10. Fig. 4a shows an initial step in which a base sheet having a web 12 and loop fastening members 20 is provided. Only the three warp yarns 22 and the fastening loops 20 of the net 12 are shown in cross-section, however, the weft yarns 24 are omitted. The fastening members 20 are attached to the base portions 28 wrapped around the web such that the base portions 28 and the strands 22 (and/or the strands 24) are joined along the contact faces 30. The loop portion of the element 20 projects on the underside 16 of the net 12.

Fig. 4b shows the application of a metallic primer layer 34 to the exposed outer surface area 32 of the web 12 and the fastening member 20 such that the web 12 and the element 20 become substantially entirely embedded within the primer layer 34. These exposed surface regions 32 are not coincident with the contact surface 30, meaning that the primer layer 34 is not applied directly to the surface regions 30 between the web 12 and the fastening member 20.

Fig. 4c shows the application of the metal coating 36 to the exposed surface of the primer layer 34 such that the web 12 with primer layer 24 and the fastening member 20 become substantially entirely embedded within the coating 36. Fig. 4c also shows that the deposit with diamond particles 38 is embedded in the portion of the metal coating 36 that appears on the upper surface side of the mesh 12. The resulting coating 36 secures the member 20 and strands 22(24) to each other and, at the same time, forms a metallic matrix material for securing the diamond particles 38 embedded therein in place.

The present invention may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the invention is, therefore, indicated by the appended claims rather than by the foregoing description. It will be apparent to those skilled in the art that alternative or equivalent embodiments of the invention may be devised and practiced. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.

Those skilled in the art and informed by the teachings herein will recognize that the present invention is applicable to any mesh or net that integrates a heat conductive hook surface or can be made into a heat conductive hook surface or loop surface. The screen may also be, for example, an extruded screen, a slit-and-expanded screen of material, a knitted screen, or a welded screen. It will be clear to the person skilled in the art how to wind the fastening members of a hook and loop system into the wire mesh or integrate them differently in the wire mesh. The choice of hook or loop on the abrasive article is determined by the type of fastening member provided on the base pad of the abrading tool.

The size and shape of various contemplated abrasive articles according to the present invention may be adjusted to fit the size of the base pad or mounting member of various abrading tools. An exemplary alternative is a disc-shaped abrasive article having a diameter of about 1 cm to several tens of cm. Other alternatives are closed-loop cylindrical sheets having a width comparable to their diameter or elongated closed-loop bands having a length significantly greater than their width. Still other embodiments include square or rectangular abrasive sheets having a width in the range of 10mm to 60cm and a length in the range of 10mm to 10 m. Abrasive pads having alternative shapes, such as (rounded) triangular, trapezoidal or pentagonal, are also contemplated.

In the embodiment described above, the abrasive particles 38 are densely, but randomly, distributed along the upper side of the article 10. In alternative embodiments, the particles may be distributed in a non-uniform manner to form a plurality of localized deposits that are shaped in a predetermined pattern on the upper surface of the article, for example to optimize the function of the abrasive article, or to make the abrasive article more aesthetically appealing.

In the above embodiment, the mesh and the fastening member are formed of resin-coated polyester fibers. In alternative embodiments, the mesh may be formed of other types of (continuous) fibrous materials, as long as the resulting filaments/strands/yarns are flexible and have high heat resistance (resistance to melting/combustion/thermal decomposition temperatures of at least 160 ℃) and high ultimate tensile strength (of at least 100MPa) along their length.

Furthermore, the shape of the openings in the screen should not be seen as limited to square openings. In alternative embodiments, the openings of the screen may have a regular cell shape, such as square, honeycomb, triangular or other polygonal shape, or even a combination of different shapes.

Claims

1. A method for making an abrasive article (10), the method comprising:

-providing a base sheet comprising a support layer (12), and a plurality of fastening members (20) of a quick release system QRS (18, 19); wherein the support layer defines a plurality of openings (26) extending therethrough from a first surface (14) of the support layer to a second surface (16) of the support layer opposite the first surface and configured to allow abrasive dust to pass therethrough; and wherein the fastening members (20) are fixed on or in the support layer and protrude from the second surface of the support layer and are configured to temporarily fix the abrasive article to a surface of a plurality of complementary fastening members (19) comprising the QRS;

-applying a coating (36) onto the support layer and the fastening member, the coating being electrically and thermally conductive;

-applying a plurality of abrasive particles (38) onto at least a portion of the first surface of the support layer such that the abrasive particles are thermally connected with the coating;

wherein the coating covers both the support layer and the fastening members and forms a thermally conductive path from the abrasive particles on the first surface to the fastening members on the second surface of the support layer via the openings.

2. The method according to claim 1, wherein the fastening member (20) is fixed directly on or in the support layer (12) before applying the coating (36), and wherein the method further comprises:

-applying the coating (36) to cover the exposed outer surface (32) of the support layer and the exposed outer surface of the fastening member and to extend in a continuous manner across the exposed outer surface (32) of the support layer and the exposed outer surface of the fastening member.

3. The method of claim 1 or claim 2, wherein the coating (36) forms a matrix layer, and wherein the method further comprises:

-applying the coating (36) onto the support layer (12) and onto the fastening members (20) by co-deposition using an electrolyte, and embedding the abrasive particles (38) in the portion of the coating (36) present at the first surface (14) of the support layer.

4. The method of any of claims 1-3, further comprising:

-applying a metallic base coat (34) directly onto the support layer (12) and the fastening member (20) by using electroless plating before applying the coating (36); and

-applying the coating (36) onto the metallic base coat (34) by using electroplating or electrolyte co-deposition.

5. The method of any of claims 1-4, further comprising:

-providing the substrate sheet shaped as an elongated fabric stored on a roll (52) or a folded stack;

-unwinding or opening a plurality of consecutive fabric portions (53) of the substrate sheet from the roll or the folded stack, continuously or intermittently;

-continuously or intermittently applying the coating (36) onto the support layer (12) and onto the fastening members (20) and applying abrasive particles (38) onto the first surface of the support layer of respective consecutive fabric portions (53) that have been unrolled or opened, thereby forming a plurality of fabric portions (55) of a semi-finished abrasive sheet; and

-cutting a pre-set shape from at least one of a plurality of fabric portions (55) of the semi-finished abrasive sheet to form the abrasive article (10).

6. The method according to any one of claims 1-5, forming the abrasive article (10) as a pad, disc, sheet, or belt configured to perform a grinding and/or polishing process.

7. An abrasive article (10) for treating a surface, comprising:

-a base sheet comprising a support layer (12), and a plurality of fastening members (20) of a quick release system QRS (18, 19); wherein the support layer (12) defines a plurality of openings (26) extending therethrough from a first surface (14) of the support layer to a second surface (16) of the support layer opposite the first surface and configured to allow abrasive dust to pass therethrough; and wherein the fastening members (20) are fixed on or in the support layer and protrude from the second surface of the support layer and are configured to temporarily fix the abrasive article to a surface of a plurality of complementary fastening members (19) comprising the QRS;

-an electrically and thermally conductive coating (36), the coating (36) covering both the support layer and the fastening means; and

-a deposit having a plurality of abrasive particles (38) covering at least a portion of the first surface (14) of the support layer and being thermally connected to the coating;

wherein the coating forms a thermally conductive path from the abrasive particles on the first surface to the fastening member on the second surface of the support layer via the opening.

8. The abrasive article (10) according to claim 7, wherein the support layer (12) is an open mesh formed from a plurality of strands (22,24), the plurality of strands (22,24) intersecting or intersecting one another and defining a plurality of openings (26) between the plurality of strands (22, 24).

9. The abrasive article (10) according to claim 8, wherein the fastening members (20) are integrated with the strands (22,24) of the netting such that the fastening members and the strands engage along a contact surface (30), and such that the coating (36) covers and extends across both the netting and the fastening members in a continuous manner without extending directly between the fastening members and the strands along the contact surface.

10. The abrasive article (10) according to any one of claims 7-9, wherein the fastening member (20) is formed from a plurality of monofilaments having bases (28), the bases (28) being mechanically fixed to the support layer (12) or being incorporated into the support layer (12).

11. The abrasive article (10) according to claim 10, wherein the bases (28) of the plurality of monofilaments are embedded in or intertwined with a plurality of strands (22,24) forming the support layer (12).

12. The abrasive article (10) according to any one of claims 8-11, wherein the web is formed from a plurality of woven, braided, or knitted strands.

13. The abrasive article (10) according to any one of claims 8-11, wherein the web is an extruded web, a punched web, or a web of slit-expanded material.

14. The abrasive article (10) according to any one of claims 8-13, wherein the web is flexible.

15. The abrasive article (10) according to any one of claims 8-14, wherein the web is made of a plurality of polyester fibers.

16. The abrasive article (10) according to any one of claims 7-15, wherein the plurality of openings (26) in the support layer (12) have an open area in a range of 20% to 60% of the surface area of the abrasive article.

17. The abrasive article (10) according to any one of claims 7-16, wherein the plurality of openings (26) in the web are disposed in a regular pattern having one or more of the following properties:

-a two-dimensional periodicity;

-mirror symmetry;

discrete rotational symmetry.

18. The abrasive article (10) according to any one of claims 7-17, being a rotationally symmetric pad, and wherein the support layer (12) and the plurality of openings (26) have discrete rotational symmetry.

19. The abrasive article (10) according to any one of claims 7-18, wherein the coating (36) is a metal coating consisting essentially of nickel or a nickel-based alloy.

20. The abrasive article (10) of any of claims 7-19, wherein the plurality of abrasive particles (38) consists essentially of diamond or cubic boron nitride.