WO2000041850A1 - Produit abrasif en non-tisse a duree d'utilisation accrue - Google Patents

Produit abrasif en non-tisse a duree d'utilisation accrue Download PDF

Info

Publication number
WO2000041850A1
WO2000041850A1 PCT/US2000/000798 US0000798W WO0041850A1 WO 2000041850 A1 WO2000041850 A1 WO 2000041850A1 US 0000798 W US0000798 W US 0000798W WO 0041850 A1 WO0041850 A1 WO 0041850A1
Authority
WO
WIPO (PCT)
Prior art keywords
web
abrasive
abrasive product
filaments
product
Prior art date
Application number
PCT/US2000/000798
Other languages
English (en)
Inventor
Ronald E. Lux
Original Assignee
3M Innovative Properties Company
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 3M Innovative Properties Company filed Critical 3M Innovative Properties Company
Priority to EP00902399A priority Critical patent/EP1152866B1/fr
Priority to DE60010663T priority patent/DE60010663T2/de
Priority to JP2000593447A priority patent/JP4718013B2/ja
Publication of WO2000041850A1 publication Critical patent/WO2000041850A1/fr

Links

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24DTOOLS FOR GRINDING, BUFFING OR SHARPENING
    • B24D3/00Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents
    • B24D3/001Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents the constituent being used as supporting member
    • B24D3/002Flexible supporting members, e.g. paper, woven, plastic materials
    • B24D3/004Flexible supporting members, e.g. paper, woven, plastic materials with special coatings
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24DTOOLS FOR GRINDING, BUFFING OR SHARPENING
    • B24D11/00Constructional features of flexible abrasive materials; Special features in the manufacture of such materials
    • B24D11/001Manufacture of flexible abrasive materials
    • B24D11/005Making abrasive webs
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24DTOOLS FOR GRINDING, BUFFING OR SHARPENING
    • B24D11/00Constructional features of flexible abrasive materials; Special features in the manufacture of such materials
    • B24D11/04Zonally-graded surfaces
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24DTOOLS FOR GRINDING, BUFFING OR SHARPENING
    • B24D3/00Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents
    • B24D3/02Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents the constituent being used as bonding agent
    • B24D3/20Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents the constituent being used as bonding agent and being essentially organic
    • B24D3/28Resins or natural or synthetic macromolecular compounds
    • B24D3/32Resins or natural or synthetic macromolecular compounds for porous or cellular structure
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24DTOOLS FOR GRINDING, BUFFING OR SHARPENING
    • B24D7/00Bonded abrasive wheels, or wheels with inserted abrasive blocks, designed for acting otherwise than only by their periphery, e.g. by the front face; Bushings or mountings therefor
    • B24D7/02Wheels in one piece
    • DTEXTILES; PAPER
    • D04BRAIDING; LACE-MAKING; KNITTING; TRIMMINGS; NON-WOVEN FABRICS
    • D04HMAKING TEXTILE FABRICS, e.g. FROM FIBRES OR FILAMENTARY MATERIAL; FABRICS MADE BY SUCH PROCESSES OR APPARATUS, e.g. FELTS, NON-WOVEN FABRICS; COTTON-WOOL; WADDING ; NON-WOVEN FABRICS FROM STAPLE FIBRES, FILAMENTS OR YARNS, BONDED WITH AT LEAST ONE WEB-LIKE MATERIAL DURING THEIR CONSOLIDATION
    • D04H3/00Non-woven fabrics formed wholly or mainly of yarns or like filamentary material of substantial length
    • D04H3/08Non-woven fabrics formed wholly or mainly of yarns or like filamentary material of substantial length characterised by the method of strengthening or consolidating
    • D04H3/12Non-woven fabrics formed wholly or mainly of yarns or like filamentary material of substantial length characterised by the method of strengthening or consolidating with filaments or yarns secured together by chemical or thermo-activatable bonding agents, e.g. adhesives, applied or incorporated in liquid or solid form

Definitions

  • This invention provides a durable, nonwoven abrasive product having a significantly longer useful product life compared to conventional, but similar abrasive products.
  • Nonwoven, low-density abrasive products made of a uniform lofty web of continuous three-dimensionally bonded polyamide filaments have found successful application for treating or conditioning various types of surfaces. These applications include, in part, removing mill scale from steel coil stock, blending of weld lines, preparing surfaces for painting or other coating operation, and removing various surface coatings in repair and maintenance operations. These successes have spurred the inevitable pursuit of providing increased value to the end user for such abrasive products and particularly for increased useable product life.
  • the low-density abrasive product life (the time it takes to wear the abrasive product from its initial diameter to a diameter equal to that of its central attachment fixture) to be much shorter than desired. Under extreme conditions, the abrasive product life may be as short as one minute or less.
  • the present invention provides an improved nonwoven abrasive product.
  • the improved abrasive product has a porous, lofty web of multiple layers of coiled, autogenously bonded thermoplastic filaments, binder resin, abrasive granules and size resin, and typically exhibits product life of at least twice that of conventional, but similar, abrasive products.
  • the present invention provides a porous, lofty web that, before adding binder resin, abrasive granules or size resin, has a coil weight in the range of between 17 and 28 g/24 in 2 (1.097 and 1.808 kg/m 2 ) and preferably in the range of between 18 and 23 g/24 in 2 (1.162 and 1.486 kg/m 2 ).
  • this invention provides a porous, lofty web that exhibits periodic coil density variations in the machine direction, referred to in this specification as "variegation", of a magnitude of between 10 and 20 mm.
  • this invention provides a porous, lofty web of multiple layers of coiled, autogenously bonded thermoplastic filaments, binder resin, abrasive granules and size resin, and exhibits a measured load at a 1.52 cm deflection (averaged values) of greater than 3.20 kg.
  • the porous, lofty web has a uniform cross-section of at least one layer of filaments.
  • Each layer of filaments includes a multitude of continuous three-dimensionally undulated filaments made of extruded thermoplastic material in which adjacent filaments are interengaged and autogenously bonded where they touch one another.
  • These undulated filaments preferably are made of polyamide polymers and have diameters of about 5 to 125 mils (0.127 to 3.175 mm) and more preferably have diameters of about 14 to 20 mils (0.355 to 0.508 mm).
  • useful amounts of variegation include those having variegation periods (distance between density peaks) of between 10 and 20 mm.
  • the porous, lofty web is impregnated or coated with a tough binder resin that both bonds a multitude of abrasive granules uniformly throughout the web and further bonds adjacent filaments to one another.
  • an additional size resin is also impregnated or coated over the web, binder resin and abrasive granules to further bond the abrasive granules to the web.
  • Drawings The present invention is illustrated and described in Figures 1-5.
  • Fig. 1 is a schematic illustration of the process used to make an abrasive product of the present invention.
  • Figs. 2-4 are perspective views that illustrate three embodiments of an abrasive product of the present invention.
  • Fig. 5 is a cross sectional view of an abrasive product of this invention.
  • thermoplastic filaments other than polyamide filaments from which to make the lofty web have been unsuccessful.
  • Attempts to produce a tougher, denser abrasive product by using finer filaments have resulted in process difficulties since the more numerous fine filaments cause a shadowing effect that results in insufficient resin and mineral penetration into the thickness of the lofty web.
  • Still further attempts at using larger filament diameters have resulted in an abrasive product that has large voids in the lofty web due to higher amplitude oscillations of the molten filaments as they are integrated into a web.
  • Variegation or the occurrence of density variation in the machine direction, has long been considered a defect in the manufacture of low-density abrasive products made of a uniform lofty web of continuous three-dimensionally bonded filaments.
  • Variegation is, at least in part, a function of extrusion rate, melt temperature, quench tank geometry, quench fluid temperature, or harmonic mechanical motions of rollers, that occur during manufacture. Under conventional or typical operating conditions, variegation is not visually detectable. Under conditions of high extrusion rates and line speeds, variegation becomes visually detectable, and was considered to yield an unacceptable web. This empirical observation has served to limit production speeds practicable to make such abrasive articles.
  • the bending stiffness of low-density abrasive products made of a uniform lofty web of continuous three-dimensionally bonded polyamide filaments has been long considered to have a relatively low useful maximum value, typically less than 3.20 kg. This low maximum value has been maintained because of the undesired operating vibrational forces typically encountered when using such low-density abrasive articles having a measured load at a 1.52 cm deflection values of greater than 3.20 kg.
  • the end user will employ such articles not as a wheel where the abrasion is induced at the circumference of the article, but instead as a disc, where the abrasion occurs on a face of the disc.
  • Such uses when abrading a workpiece on the face of the disc impart substantial lateral forces on the abrasive article.
  • these types of uses may result in the article being flexed nearly 90° out-of-plane during each revolution, which causes heating of the article and a resultant shortening of useful product life.
  • the present invention advantageously exploits the unexpected understanding that increasing the coil weight of a low-density abrasive product significantly increases the useful abrasive product life.
  • the abrasive product life is more than doubled when compared to the product life of conventional low-density abrasive products.
  • Useful exploitation is also made of the surprising discovery that variegation, or periodic density variation in the web along its machine direction of between 10 mm and 20 mm, actually increases overall web integrity, as exhibited by machine direction and cross direction tensile test results.
  • the present invention also provides a low-density abrasive product that has a significant increase in the useful abrasive product life when the measured load at a 1.52 cm deflection value is greater than 3.20 kg.
  • "Coil" refers to the web of undulated polymeric filaments prior to the application of any coatings or particles.
  • Variegation refers to a sustained periodic variation of web (coil) density arising from manufacturing process conditions that is manifested as alternating higher and lower density “stripes” or “streaks" ("variegation pattern") traversing the web in the cross-machine direction, the periodicity appearing in the machine direction.
  • the abrasive product can be formed in a continuous process, if desired, virtually directly from the basic ingredients, i.e., from polyamide filament-forming material, liquid curable binder resin and abrasive granules. That is, the polyamide filament-forming material can be extruded directly into a lofty, open, porous, filament web. Abrasive granules, binder and size resins are then applied to the web to provide the finished abrasive product.
  • polyamide filament-forming material is inserted into an extruder equipped with a spinneret head which has a multitude of openings equally spaced in at least one row, preferably in a plurality of spaced rows of equally spaced openings.
  • the row or rows of molten filaments are then extruded downwardly, permitted to freely fall a short distance through an air space and then into a quench bath.
  • the filaments enter the quench bath, they begin to coil and undulate, thereby setting up a degree of resistance to the flow of the molten filaments, causing the molten filaments to oscillate just above the bath surface.
  • the spacing of the extrusion openings from which the filaments are formed is such that, as the molten filaments coil and undulate at the bath surface, adjacent filaments touch one another.
  • the coiling and undulating filaments are still sufficiently tacky as this occurs, and where the filaments touch, most adhere to one another to cause autogenous bonding to produce a lofty, open, porous filament web.
  • the web is then directed into the quench bath between opposed rollers positioned a distance below the surface of the quench bath where the filaments of the integrated mat will still be sufficiently plastic to be permanently deformed as they pass therebetween.
  • These rolls are operated at the same speed but in opposite directions to draw the formed filament web away from the area where the filaments initially coil and bond together.
  • the rolls are spaced to contact the surfaces of the web with slight pressure sufficient to smooth any uneven surface loops or undulations to provide a web with generally flat surfaces.
  • the roller contact will not provide a higher density of filaments at either surface of the web. Instead, the web will have a defined thickness after being passed between the rollers.
  • the surfaces of the rolls are preferably smooth to produce the generally flat surface.
  • the roll surfaces may have other configurations to provide an abrasive product with a modified surface.
  • a pleated surface roller will produce webs with a pleated surface.
  • the roller surface may have spikes uniformly disposed on its surface to provide for more secure web handling.
  • the rolls are operated at a surface speed substantially slower than the extrusion speed to permit sufficient time for the filaments to coil and undulate and form a lofty web with a high degree of undulation in each filament. This process produces a web wherein each filament is coiled and undulated throughout its length.
  • the undulations of each filament are typically irregular although it is possible to adjust the process to produce regular helically coiled filaments.
  • Irregular filament undulation is characterized by random looping, kinking or bending of the filaments through the web in a pattern defined generally by the pattern of openings of the spinneret. It should be noted that, where more than one row of filaments is extruded, a web is produced having layers of coiled and undulated filaments, each layer representing a row of extruded filaments. Each layer is discernible, sometimes with great difficulty, in the web. The adjacent filaments between layers will also be autogenously bonded together for the most part where they touch one another. This aspect of a multilayer web is shown in Fig. 5 which illustrates four rows 41, 42, 43 and 44 of undulated filaments 45. Note the outer rows 41 and 45, respectively, have substantially flat surfaces 46 and 47, respectively.
  • polyamide filament-forming material is heated to a molten state and extruded from an extrusion spinneret 10 which contains at least one row of openings to provide a bundle of free-falling filaments 11.
  • Filaments 11 are permitted to freely fall through an air space into a quench bath 12 where they coil and undulate at or near the surface of bath 12 to form an autogenously bonded web 13.
  • web 13 is then passed between opposed smooth-surfaced rollers 14 and 15 which may have a pattern of uniformly spaced spikes projecting from the roller surface which are positioned to provide a substantially flat- surfaced web.
  • Web 13 is then drawn around one of the rollers, e.g., roller 15, for removal from quench bath 12.
  • Web 13 is then passed over idler roll 16 between guide roll set 17 and dried in forced air oven 18 to remove residual quench liquid.
  • the web is wound onto a roll and stored for about 4 weeks to allow morphological equilibration.
  • the web is then passed through roll coating station 19 where liquid curable binder resin 20 is applied to web 13.
  • Other conventional web coating techniques may be employed to coat the web so long as such techniques provide a substantially uniform binder resin coating.
  • dip coating and spray-coating techniques may also be used.
  • the binder resin coating should be sufficient to permit uniform coating of the web with abrasive granules.
  • the wet coated web is passed beneath a first abrasive granule dropping station 21 to coat one side of the web with abrasive granules and deployed in an S-shaped arrangement around suitable idler rollers 21a, 21b, 21c, 21d and 21e to reverse the web surfaces (that is, face the bottom side up).
  • the other surface of the web is then passed under a second abrasive granule depositing station 22 to provide a web, which has been coated on both web surfaces with abrasive granules.
  • abrasive granule applications or coating devices may also be used; e.g., the abrasive granules may be applied by spray methods such as employed in sandblasting except with milder conditions, by electrostatic coating methods, and the like.
  • the abrasive granule-coated web is then passed through forced air oven 23, to cure the first binder resin coating and then a second coating of a size resin is applied with a suitable device such as spray station 24 which simultaneously sprays top and bottom surfaces of the web with a quantity of size resin material which will bond the abrasive granules to the surface of the web.
  • a suitable device such as spray station 24 which simultaneously sprays top and bottom surfaces of the web with a quantity of size resin material which will bond the abrasive granules to the surface of the web.
  • the quantity of the size resin coating should be limited so it will not cover or mask the abrasive granules.
  • Typical shapes of the abrasive product of the invention include those depicted by Figs. 2, 3 and 4.
  • Fig. 2 shows a rectangular shape abrasive product 30 while Fig. 3 shows an annulus shape abrasive product 50.
  • Fig. 4 shows yet another embodiment which is made by stacking several layers of the web after the second application of binder resin but prior to the second curing step, compressing the stack and curing to provide a relatively densified abrasive product which may be cut into any of a variety of shapes such as a cylinder.
  • the filament-forming material which is extruded to provide the lofty web contained in the low-density abrasive product of the invention is formed of a thermoplastic polyamide material which can be extruded through extrusion orifices to form filaments.
  • Particularly useful polyamide materials for forming the filaments of the web of the abrasive product of this invention are polycaprolactam and poly(hexamethylene adipamide) (e.g., commonly referred to as nylon 6 and nylon 6,6).
  • Other useful filament- forming materials may include polyolefins (e.g., polypropylene and polyethylene), polyesters (e.g., polyethylene terephthalate), polycarbonates and the like.
  • the webs produced by the process described above are particularly suited for abrasive products because they are extremely open, porous, and lofty which permits prolonged usage of the abrasive product for conditioning (for example, surfaces where large amounts of attrited matter are produced), without filling the web and thus interfering with the abrasive product's properties.
  • the degree of openness and loftiness is evidenced by the web void volume which is typically at least about 80% (preferably about 85% to about 97%) in the uncoated state.
  • the web Upon coating with the binder resin, the web also has a considerable degree of structural integrity that permits prolonged usage of the abrasive article.
  • the flattening effect of the rollers provides a unique abrasive structure that is highly open at the surface yet has a flat face capable of use on flat surfaces without requiring bending or modification of the web. Additionally, the web, even with the binder resin coating and abrasive granules, is flexible and conformable and will typically conform to most surfaces upon which it is used.
  • the web may be made in a wide variety of thicknesses, limited principally by the design of the spinneret through which it is extruded and the gap between rollers 14 and 15 illustrated in Fig. 1. Typical web thicknesses useful for abrasive products will vary between 1/4 inch to 3 inches (0.63 to 7.6 cm).
  • the filament diameter of the filaments in the web produced by the process described above may be varied by modification of the web-making process. Typically, the filament diameter for a suitable web will be on the order of 5 to 125 mils (0.127 to 3.175 mm), but preferably is on the order of 14 to 20 mils (0.355 to 0.508 mm).
  • spinneret extrusion openings of 5 to 125 mils (0.127 to 3.175 mm) will produce such webs.
  • the openings in the spinneret will be in rows, as previously stated, and separated by at least about 0.1 inch (2.54 mm) to produce satisfactory results.
  • the openings of adjacent rows may be offset from one another although the spinneret performs suitably when the openings in the rows are aligned.
  • the free fall height may vary between about 2 to 20 inches (5.08 to 50.8 cm) to produce a satisfactory product. Typically the free fall height will be on the order of from 5 to 15 inches (12.7 to 38.1 cm).
  • Nariegation manifests itself as a density variation periodicity.
  • the peak-to-peak spacing of this periodicity increases as the production rate increases.
  • the frequency of the periodicity increases as the production rate is decreased.
  • Nariegation may be detected analytically, but at some minimum amplitude or some maximum frequency, this pattern may be detected visually as discernibly heavier streaks that traverse the web in a cross- machine direction.
  • harmonic distortions due to local boiling of the quench fluid are harmonic distortions due to local boiling of the quench fluid (and are therefore influenced by extruder output, extrusion die design, extrusion temperatures, quench conditions, and materials and additives), motion-induced standing waves in the quench tank (that are therefore dependent, at least in part, on the design and dimensions of the quench tank), asynchronous operation of the various rollers that contact the web, and/or a combination of the above.
  • motion-induced standing waves in the quench tank that are therefore dependent, at least in part, on the design and dimensions of the quench tank
  • asynchronous operation of the various rollers that contact the web and/or a combination of the above.
  • the resultant web or coiled substrate weight should weigh between 17 and 28 g/24 in 2 (between 1.097 and 1.808 kg/m 2 ) and preferably should weigh between 18 and 23 g/24 in 2 (1.162 and 1.486 kg/m 2 ). Lesser weights do not provide the increased useable life of the resulting abrasive product. Heavier web weights result in a product that is insufficiently compliant to smoothly run against a typical workpiece. For longest end-product life, variegation is present. The preferred period of variegation is between 10 and 20 mm (peak-to-peak). The widths in the machine direction of the higher density variegated areas are typically about 5 to 10 mm.
  • the preferred binder resin employed in the production of the present abrasive products has a liquid state to provide a coatable composition, yet it can be cured to form a tough, adherent material capable of adherently bonding the abrasive granules to the web even under aggressive use conditions.
  • the binder resin when cured will have a tensile strength of at least 3000 psi (2.06 x 10 4 kPa) and an ultimate elongation of at least 180% and a Shore D hardness of at least 40.
  • the presently preferred resin binder material is a polyurethane which may be prepared from commercially available isocyanate prepolymeric materials such as materials sold under the trade designation ADIPRENE L type, for example, L-83, L-100, L-167, and L-315 (commercially available from Crompton & Knowles Corporation, Stamford, CT), which may be cured with, for example, p, p'-methylene dianiline (MDA).
  • ADIPRENE L type for example, L-83, L-100, L-167, and L-315
  • MDA p, p'-methylene dianiline
  • the reactive isocyanate groups of these materials may be blocked with blocking agents such as ketoxime or phenol to give a liquid material that may be cured with MDA.
  • the uncured, unblocked prepolymeric materials will have a nominal NCO content of from about 3% to 10%, a nominal viscosity at 30°C of about 6000 to 30,000 cps and a specific gravity of about 1.03 to 1.15 at 25°C.
  • the quantity of binder resin is sufficient to adherently bond the abrasive granules throughout the web to provide a long-lifed abrasive product yet is limited so that it will not cover or mask the abrasive granules themselves.
  • the binder resin also provides for additional filament to filament bonding in the web itself. While these filaments have been autogenously bonded together during the web forming operation, they may still be separated, especially if large mechanical forces are applied to the abrasive product.
  • the binder resin should be applied in an amount between 4.8 to 16.2 (dry) g/24 in 2 (0.310 to 1.050 kg/m 2 ).
  • a lesser amount of binder resin will not provide the long life. Heavier coatings will cause the abrasive product to be too stiff for use in some applications causing vibrations during operation. Problematic "smearing", or transfer of binder resin to the surface of the workpiece, will also be more likely at higher coating weights.
  • Suitable abrasive granules may be any known abrasive particles or materials commonly used in the abrasive articles.
  • the abrasive granule size may vary from 10 grit to 600 grit (average diameter 2 to 0.01 mm) and the minerals forming the abrasive granules may vary in Mohs hardness from 4 to 10. Examples of minerals that provide useful abrasive granules include pumice, topaz, garnet, alumina, corundum, silicon carbide, zirconia, ceramic aluminum oxide, and diamond. Agglomerated granules of abrasive particles and a binder may also be useful.
  • abrasive product may also contain mixtures of several granule sizes, different abrasive materials uniformly incorporated therein or different abrasive sizes, hardnesses or materials on either surface. It will be readily apparent in view of the present invention to modify the abrasive product for a particular application by selecting the appropriate abrasive material.
  • the abrasive product of the present invention may be modified in other ways without departing from the scope of the claims.
  • additive materials may be employed in the resin binder coating such as metal working lubricants (e.g., greases, oils, and metal stearates). Such additives are typically added during the second binder coating operation so as not to interfere with granule adhesion to the filaments.
  • metal working lubricants e.g., greases, oils, and metal stearates.
  • abrasive granules should be applied in an amount between 32.4 and 97.4 g/24 in 2 (2.092 and 6.280 kg/m 2 ).
  • a second, or "size” coating of resin may be applied to the abrasive product.
  • Size resins suitable for these size coatings are constitutionally the same as those used for the initial coating, and are applied and hardened in the same manner. Preferred coating weights for size resins are between
  • Abrasive products of the present invention will have a total weight, including all coatings, of between 60.4 to 159.8 g/24 in 2 (3.9 to 10.4 kg/m 2 ).
  • Abrasive products of the present invention will exhibit variegation with a period of 10 to 20 mm, that is, with high-density peaks appearing 10 to 20 mm apart. This level of variegation in an abrasive product is likely indiscernible to the eye, but is readily detected by instrumental methods.
  • the abrasive products of the present invention may be in any of a variety of shapes as typically encountered for nonwoven abrasive products. For example, suitable shapes in both rectangular pads or disc-shaped pads which may have a central opening for attachment of an arbor for rotation. Alternatively, they may be cut into shapes such as rectangular shapes and mounted about the periphery of a rotatable hub to provide a flap wheel. Other shapes are also contemplated. During converting steps, no particular care is taken to either include or avoid any particular variegation pattern, number or variegation periods.
  • the abrasive product of this invention may be laminated to other layers to provide a modified abrasive article.
  • the abrasive product may be laminated to a foam or sponge layer to provide dual cleaning functions or to provide a cushioning layer.
  • Any of a variety of mounting devices or handles may also be applied to the abrasive product to provide an implement that may have a removable or permanently attached handle.
  • the abrasive products of the present invention are aggressive treating or conditioning implements that may be utilized in any of a variety of situations. They are much more open than most commercially available nonwoven abrasive products and thus resist loading with swarf or other residual materials produced in use. They can thus be used for much longer periods of time than conventional nonwoven abrasive products. For example, these abrasive products will remove thick, hard, tough coatings of reflective sheeting material from road signs and will remove tempering or heat-treating oxides from metal surfaces.
  • the abrasive products of the invention have an optimum balance of filament strength, resin strength and abrasive mineral adhesion to have an attrition rate such that fresh abrasive mineral particles are constantly being exposed so that the product performs consistently throughout its entire life.
  • the abrasive products of the invention have been found to perform in a superior manner to conventional nonwoven abrasive products in the following situations such as removing paint from metal and wood surfaces, removing heat-treating and tempering oxides from wire rod and circular saw blades, removing thick protective grease coatings and oxide coatings from boiler heat exchange tubes prior to welding, removing rust, dirt and contamination from steel coil during reclaiming operations, removing reflective sheeting materials from highway signs during reclaiming operations, removing slag and oxide from the surface of welded parts, and removing the protective paper coating and hard plastic coatings during the reclamation of plastic sheets such as those formed of LEXAN polymer.
  • These abrasive products also produce decorative finishes on metal parts such as stainless steel tubing and sheeting.
  • the present invention is further illustrated by the following nonlimiting examples, wherein all parts are by weight unless otherwise specified.
  • the examples according to the present invention were evaluated for performance by using a wear test.
  • the wear test rotated a disc shaped sample of the present abrasive product against a 304 stainless steel screen coupon for a period of four minutes.
  • the screen coupon consisted of a 1.90 mm thick stainless steel sheet having a hexagonal close packed array of 7.92 mm diameter holes disposed 1.25 cm (center to center) apart.
  • the abrasive discs evaluated consisted of 21.5 cm diameter disc of abrasive product which was compressed between 7.6 cm diameter holding flanges to produce a cylindrical abrasive surface. The compressed disc was rotated on a rotating shaft at a rate of 2500 rpm with a force of 6.8 kg between it and the screen coupon.
  • the screen coupon was oscillated in a linear direction along the array of holes, the array of holes being moved in 12 second cycles 13.9 cm lengthwise.
  • One disc was tested for each evaluation. In the wear test, the total weight of the coupon was measured before and after the test to determine the amount of material cut or removed (reported in the table in grams as "cut") from the screen coupon to give an indication of the relative cutting ability of the abrasive product.
  • a preferred abrasive product of the invention will have a cut of at least 5 grams for the test identified above.
  • the weight loss of the abrasive disc was also determined and is also reported in Tables 3, 5 and 6 as Disc Loss (g) (weight loss of material during testing measured in grams).
  • the weight loss for a preferred abrasive product of this invention will be less than 40 grams.
  • Uncoated web test specimens were cut to dimensions of approximately 4" x 6" (10 cm x 15 cm) and placed on a black pad to maximize contrast.
  • a video apparatus consisting of a video microscope (I ⁇ FI ⁇ INAR, available from Infinity Photo-Optical Company, Boulder, CO), a CCD camera (model 4810, available from Cohu, Incorporated, Electronics Division, San Diego, CA), and a video display device was aimed at the specimen and positioned so that the displayed field of view was about the size of the specimen. Side incident illumination was adjusted to obtain the best image contrast for elucidating the variegation structure in the webs.
  • Samples 2.0 x 7.0 x 0.5 inch (5.1 x 17.8 x 1.27 cm) were cut from each of the materials tested, in both the machine direction and cross direction of the web.
  • Three to five samples were tested using a three point bend fixture on a SINTECH (MTS Systems Corporation, Eden Prairie, MN) load frame using ASTM Standard test method D790.
  • the samples were supported between two 1.000 inch (2.54 cm) radius supports spaced 6.0 inches (15.2 cm) apart and deflected 1.000 inch (2.54 cm) at a strain rate of 10 inches/min (25.4 cm/min) using a loading nose of radius 0.50 inch (1.27 cm). This rapid strain rate exceeds that specified by ASTM D790, but more closely approximates the stresses experienced in the application of the material.
  • the data was acquired and analyzed using a computerized data system. Measured load/deflection values were recorded. The average load at 0.60 inch (1.524 cm) deflection for each example is reported in Table 6.
  • a continuous filament nonwoven web was made similarly to that of Example 1 of U.S. Patent No. 4,227,350.
  • Polycaprolactam polymer nylon 6, available commercially under the trade designation ULTRAMID B3 from BASF Corporation, Polymers Division of Mt. Olive, NJ
  • the spinneret was heated to about 248°C and positioned about 12 inches (30.48 cm) above the surface of a quench bath which was continuously filled and flushed with tap water at the rate of about 0.5 gallon per minute (about 2 liters/minute). Filaments extruded from the spinneret were permitted to fall into the quench bath where they undulated and coiled between 4 inch (10.16 cm) diameter, 60 inch (1.52 m) long smooth-surfaced rolls. Both rolls were positioned in the bath with their axes of rotation about 2 inches (5.1 cm) below the surface of the bath, and the rolls were rotated in opposite directions at a rate of about 9 feet/minute (2.74 m/minute) surface speed.
  • the rolls were spaced to lightly compress the surfaces of the resultant extruded web, providing a flattened but not densified surface on both sides.
  • the polymer was extruded at a rate of about 700 lb./hr. (318 kg/hr.), producing a 59 inches wide, 0.66 inch thick (1.50 m wide x 16.8 mm thick) web having 8 rows of coiled, undulated filaments.
  • the resulting web weighed about 20.99 g/24 in 2 (1.356 kg/m 2 ) and had a void volume of about 92.6%.
  • the filament diameter averaged between 16 to 18 mils (0.406 to 0.457 mm).
  • the web was carried from the quench bath around one of the rolls and excess water was removed from the web by drying with a room temperature (about 23 °C) air blast. Web weights and filament diameters were varied by the adjustment of roll speed, air space for filament free- fall, and extruder output to produce the examples.
  • the dried web thus formed was later converted to an abrasive composition by applying a binder resin coating, mineral coating, and size coating.
  • the binder resin coating contained the ingredient shown in Table 1 and was applied via a 2-rolI coater. Following the application of the binder resin coating to achieve about 7.78 g/24 in 2 (0.503 kg/m 2 ) dry add-on, grade 36 SiC abrasive granules were then applied to the resin coated web via a drop coater. The web was agitated to encourage penetration of the granules into the interstitial spaces of the web. 2.6 kg/m 2 of abrasive granules were applied to the web. The composition was then heated in an oven for 6 minutes at 160°C. Coating conditions were varied to produce the various dry make and mineral coatings.
  • silane coupling agent available as "Z-6040” from Dow Corning Corporation, Midland, MI.
  • Examples L9-L11 were made identically to those of Examples LI through L8, with the exception that the output and line speed were varied to produce exemplary amounts of variegation in the various webs and that the quench bath was flushed with tap water at a rate of about 10 gallons/minute (about 40 liters/minute).
  • the webs of Examples L12 and Control were made identically to those of LI through L8, with the exception that the output and line speed were varied to produce exemplary amounts of variegation in the various webs.
  • Example LI 2 By varying only these parameters, variegation levels were made from nil to extreme, the latter (Example LI 2) having density extremes varying from 0.05268 g/cm 3 to 0.01611 g/cm 3 , with the average Example L12 density being 0.0441 g/cm 3 .
  • Tensile strength was measured according to ASTM D 1682, conditions 2C- T, and the values are reported in Table 4.
  • Variegation levels were measured according to the Variegation Test. The widths of visually distinct high-density regions were measured.
  • the webs of Examples L9 and LI 1, showing advantageous variegation and nil variegation, respectively, were converted into abrasive disc products as in Examples L1-L8. The coating weights are shown in Table 5.
  • Example L13 through LI 6 and Comparative Example A were prepared identically to those of Examples L1-L8, with the exception that the weights of the various coatings were varied as shown in Table 6 and that for webs of Examples L13 through LI 6 the quench bath was flushed with tap water at a rate of about 10 gallons/minute (about 40 liters/minute). Comparative Example A was made according to Example 9 of U.S. Patent 4,227,350. The resulting webs were tested according to the Load/Deflection Test and the measured load at a 1.52 cm deflection values are reported in Table 6, showing that average load at a 1.52 cm deflection values greater than 3.20 kg were obtained for the higher various coating weights employed in Examples L 13 -LI 6.
  • Abrasive articles such as discs, made from such webs with high average measured load/deflection values exhibit surprising use life increases when operated such that lateral forces are imparted (i.e., the abrasive articles are deflected out-of-plane during operation) to the abrasive disc.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Textile Engineering (AREA)
  • Polishing Bodies And Polishing Tools (AREA)

Abstract

La présente invention concerne un produit abrasif en non-tissé amélioré. Ce produit abrasif amélioré est formé d'une bande poreuse sensiblement épaisse constituée de plusieurs couches (41, 42, 43, 44) de filaments thermoplastiques (45) enroulés et liés de manière spontanée, de résine de liaison, de grains abrasifs et de résine colle. Quand, avant l'ajout de la résine de liaison, des grains abrasifs ou de la résine colle, la bande poreuse et sensiblement épaisse possède un poids des spires situé entre 17 et 28 g/24 in2 (1,097 et 1,808 kg/m2), lesdites spires étant de densité variable dans le sens machine, et que la bande poreuse sensiblement épaisse chargée présente une valeur de charge/flexion mesurée relativement élevée, la durée de vie d'utilisation du produit abrasif (30) est fortement accrue comparée à celle des produits abrasifs réalisés à partir de bandes dont le poids de spires est moindre et dans lesquelles la densité des spires n'est pas variable dans le sens machine.
PCT/US2000/000798 1999-01-15 2000-01-13 Produit abrasif en non-tisse a duree d'utilisation accrue WO2000041850A1 (fr)

Priority Applications (3)

Application Number Priority Date Filing Date Title
EP00902399A EP1152866B1 (fr) 1999-01-15 2000-01-13 Produit abrasif durable en non-tisse
DE60010663T DE60010663T2 (de) 1999-01-15 2000-01-13 Beständiges vliesstoff-schleiferzeugnis
JP2000593447A JP4718013B2 (ja) 1999-01-15 2000-01-13 耐久性のある不織研磨製品

Applications Claiming Priority (6)

Application Number Priority Date Filing Date Title
US23126399A 1999-01-15 1999-01-15
US09/231,263 1999-01-15
US26449599A 1999-03-08 1999-03-08
US09/264,495 1999-03-08
US40193899A 1999-09-23 1999-09-23
US09/401,938 1999-09-23

Publications (1)

Publication Number Publication Date
WO2000041850A1 true WO2000041850A1 (fr) 2000-07-20

Family

ID=27398170

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2000/000798 WO2000041850A1 (fr) 1999-01-15 2000-01-13 Produit abrasif en non-tisse a duree d'utilisation accrue

Country Status (1)

Country Link
WO (1) WO2000041850A1 (fr)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6786801B2 (en) 2001-12-11 2004-09-07 3M Innovative Properties Company Method for gasket removal
DE10354848A1 (de) * 2003-11-20 2005-06-30 Brandenburgische Technische Universität Cottbus Verfahren und Einrichtung zur Herstellung von pelletartigen Körpern aus ungebundenen Fasern
WO2005117667A1 (fr) * 2004-05-20 2005-12-15 3M Innovative Properties Company Article texture tridimensionnel et procedes de fabrication
WO2011094369A2 (fr) * 2010-01-29 2011-08-04 3M Innovative Properties Company Voile de revêtement et procédé de fabrication
CN102689270A (zh) * 2011-03-22 2012-09-26 中芯国际集成电路制造(上海)有限公司 固结磨料抛光垫及其制备方法
EP3558589A4 (fr) * 2016-12-23 2020-10-07 3M Innovative Properties Company Articles abrasifs à liant polymère et leurs procédés de fabrication

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SU916287A1 (ru) * 1980-07-04 1982-03-30 Ural Vnii Abrazivov Shlifovani Способ изготовления шлифовальной шкурки с переменной плотностью зерна i
WO1998023800A1 (fr) * 1996-11-27 1998-06-04 Minnesota Mining And Manufacturing Company Filaments non-etires, resistants, pouvant etre traites par voie fondue de façon durable, a macrodeniers, thermoplastiques,multicomposants
WO1998053956A1 (fr) * 1997-05-30 1998-12-03 Minnesota Mining And Manufacturing Company Article abrasif comportant de la mullite

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SU916287A1 (ru) * 1980-07-04 1982-03-30 Ural Vnii Abrazivov Shlifovani Способ изготовления шлифовальной шкурки с переменной плотностью зерна i
WO1998023800A1 (fr) * 1996-11-27 1998-06-04 Minnesota Mining And Manufacturing Company Filaments non-etires, resistants, pouvant etre traites par voie fondue de façon durable, a macrodeniers, thermoplastiques,multicomposants
WO1998053956A1 (fr) * 1997-05-30 1998-12-03 Minnesota Mining And Manufacturing Company Article abrasif comportant de la mullite

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6786801B2 (en) 2001-12-11 2004-09-07 3M Innovative Properties Company Method for gasket removal
DE10354848A1 (de) * 2003-11-20 2005-06-30 Brandenburgische Technische Universität Cottbus Verfahren und Einrichtung zur Herstellung von pelletartigen Körpern aus ungebundenen Fasern
DE10354848B4 (de) * 2003-11-20 2005-09-29 Brandenburgische Technische Universität Cottbus Verfahren und Einrichtung zur Herstellung von pelletartigen Körpern aus ungebundenen Fasern
WO2005117667A1 (fr) * 2004-05-20 2005-12-15 3M Innovative Properties Company Article texture tridimensionnel et procedes de fabrication
WO2011094369A2 (fr) * 2010-01-29 2011-08-04 3M Innovative Properties Company Voile de revêtement et procédé de fabrication
WO2011094369A3 (fr) * 2010-01-29 2011-12-15 3M Innovative Properties Company Voile de revêtement et procédé de fabrication
US8389425B2 (en) 2010-01-29 2013-03-05 3M Innovative Properties Company Bonded mat and method for making
CN102689270A (zh) * 2011-03-22 2012-09-26 中芯国际集成电路制造(上海)有限公司 固结磨料抛光垫及其制备方法
EP3558589A4 (fr) * 2016-12-23 2020-10-07 3M Innovative Properties Company Articles abrasifs à liant polymère et leurs procédés de fabrication
US11623324B2 (en) 2016-12-23 2023-04-11 3M Innovative Properties Company Polymer bond abrasive articles and methods of making them

Similar Documents

Publication Publication Date Title
EP1152866B1 (fr) Produit abrasif durable en non-tisse
US4227350A (en) Low-density abrasive product and method of making the same
EP0984847B1 (fr) Article abrasif comportant de la mullite
EP0451944B1 (fr) Articles de finition superficielle en tissu non tissé, renforcés avec une couche polymérique et sa méthode de fabrication
US20200139513A1 (en) Nonwoven abrasive article and method of making the same
CA1165569A (fr) Article abrasif a matiere abrasive noyee dans un support en fibres
US5858140A (en) Nonwoven surface finishing articles reinforced with a polymer backing layer and method of making same
EP1165289B1 (fr) Article abrasif et son procede de fabrication; appareil a roder
JP4555080B2 (ja) 研磨製品、その製造方法および使用方法、ならびにその製造のための装置
US20160008957A1 (en) Nonwoven abrasive article containing formed abrasive particles
JP2001508362A (ja) 研磨物品とその製造方法
CA2208086A1 (fr) Articles conformables de finissage de surfaces et leur procede de fabrication
WO2001062442A1 (fr) Articles abrasifs non tisses et procedes correspondants
EP0823947A1 (fr) Articles de recurage et leur procede de fabrication
WO2000041850A1 (fr) Produit abrasif en non-tisse a duree d'utilisation accrue
US20080160879A1 (en) Method of abrading a zirconium-based alloy workpiece
WO2005117667A1 (fr) Article texture tridimensionnel et procedes de fabrication
EP1386696A1 (fr) Produit abrasive et son procédé de fabrication

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): JP

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE

121 Ep: the epo has been informed by wipo that ep was designated in this application
DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
ENP Entry into the national phase

Ref country code: JP

Ref document number: 2000 593447

Kind code of ref document: A

Format of ref document f/p: F

WWE Wipo information: entry into national phase

Ref document number: 2000902399

Country of ref document: EP

WWP Wipo information: published in national office

Ref document number: 2000902399

Country of ref document: EP

WWG Wipo information: grant in national office

Ref document number: 2000902399

Country of ref document: EP