MXPA97004749A - Article of conformable superficial finishing, and method for the manufacture of the mi - Google Patents

Abstract

The present invention relates to an article for surface finishing, characterized by: a three-dimensional non-woven raised net, of fibers having at least one larger surface, said fibers being joined to each other at their points of mutual contact; porous reinforcement resistant to re-stretching having first and second major surfaces, the first major surface of the fabric is positioned on and along a larger surface of the non-woven network, a layer comprising a flexible polymer coated on and coextensive with the second surface of the fabric, the layer having an exposed surface of low pressure and portions extending through said reinforcing fabric encapsulating the fibers along a larger surface of the

Description

ARTICLE OF CONFORMABLE SUPERFICIAL FINISH, AND METHOD FOR THE MANUFACTURE OF THE SAME This invention relates to a conformable surface finishing article, comprising a three-dimensional nonwoven web reinforced with fabric, and to a method for manufacturing such an article. The fibrous, three-dimensional, non-woven, conformable surface finishing articles are known to eliminate corrosion, surface defects, roughness and the like, as well as to impart desirable surface finishes on various articles of aluminum, brass, copper, steel, and wood, for example. Such articles include discs, endless bands and pads made according to the teachings of US Patent No. 2,958,593 issued to Hoover et al. Such articles for nonwoven surface finishes have not been completely satisfactory, since they can become entangled on the sharp edges or stretch and break when in the form of endless bands. It is desirable, therefore, to develop surface finishing articles comprising non-woven portions which are REF: 24964 strong and resistant to stretching and ripping during use. Efforts to reinforce the non-woven surface finishing products have included needle basting the three-dimensional network, fixing the net to a non-woven backing or backing or a combination thereof. The resulting articles, although widely used, have also been less than satisfactory in some applications. The needle basting of the nonwoven web, for example, produces denser areas which carry the abrasive / binding requirements at higher loads to other areas within the network. These densified areas form more aggressive, harder abrasive surfaces, which can scratch the workpiece in subsequent applications for surface finishes. In addition, woven backing reinforcements often lack conformability to engage the contours on many surfaces, resulting in "edge cuts" where the edge of the movable band cuts aggressively in the contoured areas of the workpiece. Finishing operations such as the final finishing of fine furniture, musical instruments, or items for performing activities such as skis, for example, are exemplary of surface finishing operations that require improved articles for surface finishing. Accordingly, there is a need for a non-woven surface finishing article which is resistant to tearing, stretching and / or breaking during use, while at the same time being flexible and conformable for use under contoured surfaces. Preferably, the non-woven web in such article may not include densified abrasive areas. Other efforts to provide articles for appropriate nonwoven surface finishes have used an open mesh fabric to force the nonwoven web. Frequently, the net is stitched with needles and the sewn fibers of the net are projected through the web. Such bands of woven, stretch-resistant surface finish show improvements in tear strength and in some uses on contoured surfaces where the band is supported against the work piece, by a contact wheel. However, in applications where a stationary platen is pushed against the band, excessive friction against the platen and needle-sewn non-woven fibers projecting through the woven fabric generates significant heat that can scorch the platen during operation. In addition, the roughness of the non-abrasive surface of such bands can prevent the application of uniform pressure by the platen and thereby prevent smooth running of the strip on the workpiece. Therefore, there is a need for an appropriate surface finish article for use on contoured surfaces, and which can be operated by using a stationary platen to provide a consistent finish on the workpiece, and without excessive wear of the platen. It may be desirable to provide such an article with a reinforcement that provides a smooth surface of low friction, and wherein the nonwoven web lacks densified abrasive areas. The present invention provides articles for non-woven, conformable surface finishes, and a method for the manufacture of such articles. The articles of the invention include bands, pads, discs, abrasives, and for polishing, and the like which include a suitable low friction surface in belt applications where a platen pushes the article against a workpiece.

In one aspect of the invention, there is provided a surface finishing article comprising a three dimensional raised net woven of fibers having at least one larger surface, fibers joined together at their points of mutual contact; a stretch-resistant porous reinforcing fabric having first and second major surfaces, the first major surface of the fabric being placed on and along a larger surface of said non-woven network; a layer comprising a flexible polymer coated on and coextensive with the second major surface of the fabric, said layer having an exposed surface of low friction and portions extending through the encapsulation fibers of the reinforcement fabric, throughout of a larger area of the network. In describing the details of the invention, it will be understood that certain terms have the specific meanings described therein. "Hardenable coatable composition" or "coatable composition", refers to a viscous composition comprising a polymer or components that will react to form a polymer, and which will harden into a solid polymeric layer, which remains solid at ambient conditions, as well as the working conditions for the surface finish article. "Low friction surface" refers to a polymer surface in a surface finish article which, when a platen is pushed against the surface, provides a lower coefficient of friction than the same type of surface finish article without such a polymer surface. "Surface finish article" refers to any endless belt, disk, pad or similar article comprising a three-dimensional network of non-woven fibers which is useful in abrasive or finishing operations on wood, metal, plastic or other surfaces. "Stretch value" refers to the amount in which a fabric is stretched in one direction, when it is subjected to a tension of 17,500 Newtons per linear meter of width. The stretch value is calculated as [. { stretched measurement - initial measurement) / (initial measurement)] x 100. In still another aspect of the invention, there is provided a method for the manufacture of the aforementioned surface treatment articles, which comprises the placement of a resistant reinforcing fabric to stretch,. porous having first and second major surfaces adjacent to a larger surface of a high, three-dimensional, non-woven network of fibers, such that the first major surface of the fabric substantially covers a larger surface of the network; applying a coatable composition so that a portion of the composition extends through the fabric to contact and encapsulate the fibers along a larger surface of the network adjacent to the first major surface of the fabric, while forms an exposed surface coextensive with the second major surface of the fabric; and hardening said coatable composition to provide the article for surface finishing. Preferably, the nonwoven web is not sewn with a needle. The preferred reinforcing fabric is a stretch-resistant woven material, comprising flat woven fabrics having openings between the warp and fill yarns of at least about 0.10 mm2. In general, the reinforcing fabric will comprise a woven material with sufficiently large openings in it to allow portions of the polymeric layer to extend therethrough and form discrete bonding portions with the fibers along a larger surface of the fabric. nonwoven. The effective dimensions of the openings can be varied depending on the type of polymer used and the temperature at which it is applied to the fabric. The preferred polymer is an extrudable thermoplastic material in molten form. More preferably, the polymer is nylon 6. The polymer is applied as a hardenable and recoverable composition, and typically a molten polymer. With the application of pressure, the coatable composition will be forced through the openings in the fabric to encapsulate the fibers along a larger surface of the network, while also forming an exposed surface coating of low friction and coextensive with the outer surface of the fabric. This surface may be flat with dimples or otherwise textured, as may be required. Those of skill in the art will better understand the details of the present invention after special consideration of the remainder of the description including the drawings, the detailed description of the preferred embodiment and the appended claims. In the description of the structures of the preferred embodiments of the present invention, reference is made to various drawings, wherein: Figure 1 is a perspective view of a surface finishing strip according to the present invention; Figure 2 is a perspective view of a surface finishing disk according to the present invention; Figure 3 is an enlarged sectional view of a segment of the surface finishing strip in Figure 1 taken on line 3-3 of Figure 1; and Figure 4 is a schematic diagram describing a method for manufacturing a surface finishing article according to the present invention. A conformable surface finish article is provided in any of the various forms such as endless bands, discs, pads and the like. The articles of the invention comprise a network of non-woven surface finish secured to a stretch-resistant reinforcing fabric, by a polymeric coating that provides a low friction surface suitable for the application of a platen or thick plate thereto. The polymeric coating portions extend through the fabric layer to form discrete bonding areas with the fibers, from which a polymer, the fabric and the non-woven web are joined in a unitary finished article. In the discussion of the details of the preferred embodiments, reference is made to the various figures, wherein the structural features are designated using reference numbers, and where similar reference numbers indicate similar structures. With general reference to the figures, the surface finishing article of the invention is shown in the form of an endless band 10 (Figure 1). A three-dimensional non-woven web 12 and a woven stretch-resistant reinforcing fabric 14 are components of the web 10. The non-woven network 12 includes a first major surface 12a or internal, and a larger surface 12b or external, with the second surface 12b which is the working surface of band 10 (see figure 3). The reinforcing fabric 14 preferably comprises a non-woven material having a plurality of openings therethrough (generally indicated at 15). The fabric 14 is applied against the first surface 12a of the non-woven layer 12. An adjacent flexible polymeric layer 16 extends over and is coextensive with a larger surface of the fabric 14 that forms the exposed surface of 17a, and which provides a surface of drive of the band 10, which in use could be carried on drive rolls and supported between them on a platen of a surface finishing machine (not shown). The exposed surface 17a is preferably a low friction surface to prevent the production of heat between it and the surface of the stage. The portions 17b (FIG. 3) of the polymeric layer 16 extend through the openings of the fabric 14, to form discrete bonding areas with the fibers 11 along the first major surface 12a of the non-woven layer 12. The articles of the present invention may also be provided in the form of discs such as the disc 18 shown in Figure 2. The disc 18 may include a central opening 20 to facilitate assembly. Except for its converted external shape, the internal structure of the disc 18 is identical to that of the band 10 of Figure 1, including a non-woven layer 12, a woven material 14, and a polymeric material 16, as described above. The articles for surface finishes of the invention also comprise the surface finishing pads (not shown) having the profile described above which can be cut or converted to any of a variety of shapes, for example, rectangular, square, circular, ovals, etc. All articles for surface finishing of this type have the features described, will be understood as within the scope of the present invention. Further details of the components of the surface finishing articles of the invention are given below.

The Non-Woven Network The non-woven web comprises a non-woven, fibrous, low density, open, raised web made of suitable synthetic fiber such as nylon, polyester and the like. The network is preferably able to withstand the temperatures at which the impregnation resins and the adhesive binders are cured without deterioration. The fibers of the net are preferably endowed with tensile strength and wavy, but may also be continuous filaments formed by a nonwoven fabric production process made of fused filaments, such as that described in the North American Patent of Invention No. 4,227,350 to Fitzer, for example. The fibers that are satisfactory for use in the non-woven network are between about 20 and about 100 millimeters and preferably between about 40 and about 65 millimeters in length, and have a denier in the range of about 1.5 to about 500 and preferably , from about 15 to about 100. It is contemplated that mixed denier fibers may be used in the manufacture of a non-woven portion 12, in order to obtain a desired surface finish. The use of large fibers is also contemplated to allow the inclusion of larger abrasive particles within the articles of the invention. Those skilled in the art will understand that the invention is not limited by the nature of the fibers employed or by their respective denier lengths and the like. The non-woven web is easily formed on a "Rando weaver" machine (commercially available from Rando Machine Company, New York) or can be formed by other conventional carding processes. Where a nonwoven material of the non-woven type made of fused filaments is employed, the filaments may be of a substantially larger diameter, for example, up to 2 millimeters or more in diameter. The use of larger diameter fibers allows the use of larger abrasive particles in the finished article. Useful nonwoven webs preferably have a weight per unit area of at least about 100 g / m2 and more preferably about 250 g / m2. Minor amounts of fiber within the non-woven network will provide items that have somewhat shorter commercial work beams. The weights of the above fibers will typically provide a net, prior to sewing or impregnation having a thickness of from about 6 to about 75 millimeters, and preferably about 25 millimeters. Commercially available nonwoven webs, suitable for the use of the invention, include those identified in the following examples. The nonwoven web 12 can also be optionally reinforced and consolidated by needle basting, a treatment that mechanically reinforces the nonwoven web by passing matting needles through it. During this treatment, the needles pull the fibers of the network with them while passing through the non-woven network so that, after the needle has been retracted, the individual fiber collections of the network are oriented in the direction of the thickness of the non-woven fabric. The amount or degree of needle basting can include the use of about 8 to about 20 needle penetrations per square centimeter of the net surface when needle needles are used. x 18 x 25 x 3.5 RB, F20 6-32-5.55B / 3B / 2E / L90 (commercially available from Foster Needle Company, Manitowoc, Wisconsin). The needle basting is easily achieved by the use of a conventional needle loom which is commercially available for example, from DiLo, Inc. of Charlotte, North Carolina. After the optional needle-basting step, the non-woven fabric is impregnated with either resin-abrasive slurry or a resin binder (eg, without abrasive particles) depending on the aggressiveness required of the finished article. The non-woven web is completely saturated with the resin-abrasive suspension or the resin binder using any of a number of conventional application techniques, such as spray coating, dip coating or roll coating, using a two roller coater, for example. Preferred resins for use in the coating of the non-woven network are those which, after curing, will be relatively hard and which will provide firm bonding of the constituent fibers to one another. Exemplary of the resins which are useful in the present invention include phenolic resins, aminoplast resins, having outstanding α, β-unsaturated carbonyl groups, urethane resins, epoxy resins, ethylenically unsaturated resins, acrylated isocyanurate resins, urea resins -formaldehyde, isocyanurate resins, acrylated urethane resins, acrylated epoxy resins, bismaleimide resins, epoxide resins modified with fluorine, and combinations thereof. Catalyst and / or curing agents can be added to the binder precursor to initiate and / or eliminate polymerization. Preferably, the binders used in the present invention are phenolic resins such as resole and novolac resins, described in Kirk-Othmer, Encycl opedi a of Chemical Thecnol ogy, third edition, John Wiley and Sons, 1981. New York, volume 17, pages 384-399, incorporated by reference herein. Resole phenolic resins are incorporated from an alkaline catalyst and a molar excess of formaldehyde, typically having a molar ratio of formaldehyde to phenol, between about 1.0: 1.0 and 3.0: 1.0. The novolac resin is prepared under acid catalysts and with a molar ratio of formaldehyde to phenol of less than 1.0: 1.0. Commercially available phenolic resins, suitable for use in the present invention, include those known under the trade designations "Durez" and "Varcu", available from Occidental Chemicals Corporation (N Tonawanda, New York): "Resinox", available from Monsanto Corporation; and "Arofene" and "Arotap", both available from Ashland Chemical Company. The first and / or second surfaces 12a and 12b, respectively, of the non-woven web 12 are coated with the aforementioned resin binder, which may also include optional abrasive particles. The abrasive particles can also be mentioned in a separate step after the application of the resin binder to the network 12. The abrasive particles suitable for use herein, are preferably of degree 24 or thinner, such as those normally used for finishing operations. Suitable abrasive particles include aluminum oxide including ceramic aluminum oxide, heat treated aluminum oxide and aluminum oxide fused to white; silicon carbide, alumina-zirconia, diamond, ceria, cubic boron nitride, garnet, flint, emery and combinations of the above. In addition, abrasive agglomerates such as those described in US Patent Nos. 4,652,275 and 4,799,939 can be used, the descriptions of which are incorporated by reference herein. Bands coated with abrasive mineral, satisfactory for use in finishing articles, should typically have a non-woven surface having a Shore A Hardness Tester (HA), according to ASTM Test Method D2240-86, of approximately less than 10 to approximately 85, as measured with an "A" instrument foot diameter of 5 millimeters. Although an HA value of less than 10 is considered to be outside the range of ASTM D2240, readings of about 5 have been measured on the smoother articles of the invention. A lower Durometer measurement typically results in a band that is easily torn and broken by the sharp corners of the work pieces, for example. The items of higher durometer measurements are excessively dense and will often be loaded with abrasive pieces. Where the article is to be used in polishing applications, the non-woven web 12 will usually not include abrasive particles, but may include less abrasive minerals such as talc, for example.

The reinforcing fabric The reinforcing fabric 14 is preferably a stretch-resistant woven fabric, with a low stretch value when pulled in opposite directions. A stretch value of less than 20% is preferred and a value of less than about 15% is more preferred. Suitable materials for use as a reinforcement fabric in the articles of the invention, include without limitation, thermobonded fabrics, knitted fabrics, stitched-knitted fabrics and the like. Those skilled in the art will appreciate that the invention is not limited to the selection of one reinforcing fabric over another, and it is contemplated that the invention will include any type of material which would otherwise have the required properties as described herein. One aspect of the present development is the use of a reinforcing fabric comprising a woven material with sufficiently large openings in it, to allow portions of the polymeric layer to extend therethrough, forming discrete joining portions 17b with the fibers of the nonwoven web 12, along the first major surface 12a. The effective dimensions of the openings can be varied depending on the type of polymer used and the temperature at which it is applied to the fabric. Where nylon 6 is used, the reinforcing fabric will preferably comprise flat woven fabrics having openings between the warp and fill yarns and about 0.10 mm2. A flat woven fabric that has 16 kilos of warp and 16 filler yarns per 2.54 cm (1 inch) (for example, 16 x 16) of nylon 6.6 threads of 840 denier, which have a fabric weight of 149 g / m2 (4.4 oz./yd2) is most preferred for use with a nylon polymer 6. Such material is commercially available from Highland Industries of Greensboro, North Carolina. Other materials can be used, such as those made of polyester, cotton, animal hair, other polyamides and the like. Preferably, at least one layer of fabric 14, resistant to stretching, woven, is included within articles 10 and 12 of the invention. Additional layers of fabric (not shown) can be used in addition to the first layer of woven fabric 14, to provide additional dimensional strength, as long as the openings in the woven fabrics are at least partially aligned so as not to substantially prevent extrusion of the fabric. polymer through the two layers of fabric and into the non-woven layer 12. Where two or more layers of fabric are included, they are preferably placed adjacent to one another in the finished article.

The Polymeric Layer The polymeric layer 16 encapsulates the reinforcing fabric 14, resistant to stretching, woven.

Preferably, the polymer is applied as a hardenable, curable composition in the form of a viscous fluid and typically in the molten state.

With the application of pressure, the coatable composition will be extruded through the openings in the reinforcement fabric 14 and into the nonwoven web 12. In this manner, the molten polymer flows around and encapsulates the fibers around the first major side 12a of the network 12. The polymer is then hardened in a known manner to form a continuous, thick reinforcing polymer layer 16 which forms a surface outside of the article. Preferably, the polymer is applied and hardened without significant penetration through the balance of the nonwoven web 12. The hardened polymer layer 16, comprises a flexible surface 17a of low friction, or extensive with the reinforcing fabric and portions 17b which they extend through the fabric 14 and are attached to the fibers of the net 12. The low friction backing surface 17a of the finished article can be flat without projections or depressions therein. Alternatively, the surfaces 17a may be corrugated or otherwise textured to adapt the article to a particular end use. If desired, printed signs can be applied to the surface 17a. A polymeric layer 16 is formed from a coatable composition applied to the network 12 and the fabric 14. The coatable composition may comprise liquid reactive components or a thermoplastic polymer material which has been sufficiently fluidized by heat, for example, and hardened to forming the polymeric layer 16, as described herein. Preferred are those polymers which will harden in themselves as by curing and remain solids at room temperature. The curing of the composition can be achieved in a known manner such as by heating in a furnace, exposure to ultraviolet light, the use of peroxides and the like. Alternatively, thermoplastic polymers that solidify at room temperature can also be used. The polymer layer may be within a clearly broad range of hardness ranges. Preferably, the hardness will be in the range of about Shore 50A to about Shore 80D and more preferably from about Shore 90A to about Shore 70D. It will be appreciated, however, that articles having polymeric layers with hardness values outside these ranges may be appropriate for use in specific applications, and the invention need not be considered as limited to the aforementioned hardness ranges. Softer materials of approximately Shore 90A can generate excessive friction and thermally degrade in certain applications, such as in those applications that require the use of a stationary platen, for example. These softer materials, however, may be employed in belt applications that do not require the use of a stationary platen, such as a device for tensioning polishing belts where there is relative limited movement between the back of the article for surface finishing and the medium drive used. The harder materials of approximately Shore 70D may be excessively rigid and, therefore, will generally be unsuitable for use in the formation of endless bands. However, such articles may be useful in some applications for surface finishing disc, for example. The thickness of the polymer layer is preferably between about 0.175 mm and about 1.75 mm and more preferably between about 0.250 mm and about 1.0 mm. The polymer layers smaller than about .250 mm generally lack structural integrity and durability. Thicker layers of about 1.00 mm may be undesirably stiff for use in endless bands, but may be appropriate for at least some applications involving discs or pads. In general, a thickness greater than about 1.75 mm will make the article too stiff for most applications.

In the selection of the polymer for the manufacture of the layer 16, consideration is given to the final use of the finished article, allowing the required flexibility of the article and its conformability to the surface of the work piece. An additional consideration in the formation of the endless bands, is the ability of the polymer to provide a low friction surface capable of withstanding the significant heat production caused by the application of the stationary stage, for example. An article made without the ability to withstand the heat generated during use, will experience a reduced life and may present a safety hazard. Preferably, the polymer employed in the articles of the invention is an extruded polymer in molten form, which may include compatible fillers, pigments, reinforcing fibers, antioxidants, lubricants and the like. Suitable melt extrudable polymers, for use in the invention, include thermoplastics such as nylon, polyesters, polypropylenes, polyethylene / vinyl acetate copolymers, acrylic / butadiene / styrene copolymers, and the like. Thermoplastic elastomers such as ionomers, polyesters, polyurethanes, polyamide ethers, and the like, are also suitable fused extrudable polymers. The polymeric layer can be formed from the polymerization of liquid reagents in the above-described recoverable composition and, useful reactive polymer systems include the heat-cured or radiation-cured urethane, the polyester and epoxy resins. An example of a useful liquid reagent system for use in the invention is the two-part laminated adhesive composition described in Example 1 of US Patent No. 4,331,453, incorporated by reference herein. The most preferred polymer is nylon 6, such as that which is commercially available for commercial designation "Ultramid" from BASF Corporation of Parsippany, New Jersey. In the endless bands, the polymer will preferably have a melting temperature greater than about 115 ° C as measured by differential scanning calorimetry (DSC) according to the method described in ASTM 537-86. More preferred are those polymers having a melting temperature greater than about 150 ° C, especially when used in endless bands,. which will be subject to high pressures of the work piece. Materials that have melting temperatures lower than 115 ° C can fail prematurely, especially in band applications, where a platen will be pushed against the polymer at high pressures.

Manufacturing method With reference to Figure 4, a preferred method for manufacturing the article according to the invention is schematically illustrated and will now be described. A complete batch 120 including a non-woven web 122 is fed from a feed roller 124. The non-woven web 122 may be pre-stitched with a hardened, coated needle, as described herein. A reinforcing fabric 126 is fed from the feed roll 128 to a pair of pressure rollers 130 (rolling roll) and 132 (casting roll) that rotate in the opposite direction where the non-woven web 122 and the fabric 126 are joined to form a laminate. An extrusion apparatus equipped with a film die 134 is positioned to apply a sheet of a coating composition 136 within the fastening point, so that the composition is applied to the external surface of the canvas 126. The successive layers of the fabric 126 , the coatable composition 136, and the non-woven web 122 are passed between the rolls 130, 132 which form the composition 136 by applying pressure to the opposite sides of the aforementioned layers. The coatable composition 136 is thereby forced through the pores or openings within the fabric 126, and simultaneously smoothed on the outermost surface of the fabric 126. The rotating roller 130 may be equipped with a removable surface sleeve or sleeve (not shown) or it may be plated with chrome or textured. The two rollers 130 and 132 are cooled with water at a temperature sufficient to harden the composition 136 as when it passes between the rollers 130,132. Where the composition 136 is nylon 6, the roll temperature is typically about 16 ° C. Where a textured or matte finish is desired for the polymeric layer, the roller 132 is coated with a textured material or is equipped with a suitable sleeve or sleeve to impart the desired finish.

In this way, a continuous sheet 140 of surface finishing material comprising the non-woven web 122 and the fabric 126 joined together by an uncured polymer layer is formed. The polymer layer formed in this way comprises a smooth low friction surface coextensive with the reinforcing fabric and the portions extending through the fabric forming discrete joining areas which encapsulate the fibers of the protected network 122. A roller 138 guides the web 140 of the surface finishing material to an advance regulating roller 142 from which the material 140 can subsequently be cut to form discs, pads, endless bands or the like. It will be understood that the above process can be modified and in the invention is not designed to be limited to the specific steps described above. The continuous material 140 can be fed directly from the pressure rollers 130 and 132 to a cutting station (not shown) where the sheet 140 can be cut into finished articles. It is also contemplated that the film die 134 may be cut to apply the coating composition 136 between the non-woven web 122 and the fabric 126. In such an embodiment, the pressure coming from the pressure rollers 130 and 132 will be sufficient to force the polymer fused through the side of the fabric 126 adjacent the non-woven web 122, first coating the non-woven fibers with the composition 136 and forcing the composition through the openings in the fabric, to form the smooth exposed surface of low friction, continuous of the article, as discussed above. Other modifications to the described process may be made while remaining within the contemplated scope of the invention. The inventive characteristics of the articles for surface finishing and the manufacturing methods described herein are further demonstrated in the following Examples. It is intended that all Examples be exemplary of the embodiments of the invention and not limiting in any way.

EXAMPLES Commercial Designations Reference is made to certain ingredients in the following Examples by their trade designations, which will be understood to have the meanings described below. "Ultramid" is a commercial designation for nylon 6 polymer, commercially available from BASF Corporation of Parsippany, New Jersey. "Scotch-Brite" is a commercial designation for a class of commercially available non-woven materials from the Minnesota Mining and Manufacturing Company of St. Paul, Minnesota. "High Strength A-VFN" refers to a strip-based nonwoven material that includes alumina abrasive particles (equivalent grain 220-320), available in various widths and lengths under the former "Scotch-Brite" trade designation of Minnesota Mining and Manufacturing Company. This material comprises a net not stitched with nylon fiber needle of 13.5 denier, which has been roller coated, with a polyurethane binder on which a suspension of phenolic / alumina resin has been applied and cured. The weight of the finished net for this material is approximately 774 g / m2. "Clean and Finish" is a commercial designation for a non-woven network of "Scotch-Brite", typically used in polishing applications and available from Minnesota Mining and .Manufacturing Company. The "Type T" networks used herein were needle-necked networks of 6 denier polyester fibers, which were coated with a polyurethane / talc composition and cured. The weight of the finished net for this material is approximately 523 g / m2. "Hi-Pro" is a commercial designation for a nonwoven web based on continuous filaments, commercially available from Minnesota Mining and Manufacturing Company of St. Paul, Minnesota. This material is a net not stitched with a needle, made of nylon fibers (250 microns (10 mil thick)). The fibers of the nets are coated with a urethane resin and the abrasive particles (alumina) are coated on the urethane before curing. The weight of the finished network is approximately 1423 g / m2. "Adiprene BL-16" is a commercial designation for a block polyfunctional isocyanate polymer from Uniroyal Chemical Company, Inc. of Middlebury, Connecticut. "MAG 280" is a commercial designation for an abrasive product commercially available from Hermes Abrasives, Ltd., of Germany. The product was used as a control in the comparative tests, and comprises a nonwoven web attached to a fabric reinforcement. The aluminum oxide is fixed to the nonwoven network.

Extrusion conditions The simple "Johnson Spartan" model 70 screw extruder, obtained from Johnson Plastics Machinery Company, was used in the extrusion of the polymeric layer in certain Examples, as indicated, the extruder was a 6.35 cm (2.5 inch) single screw extruder. ) equipped with a 0.61 meter (24 inch) flexible flange film die with flange space set at 0.50 mm (0.020 inches). The extruder had five temperature control zones along the barrel, which were adjusted to provide five temperature zones of 212, 240, 245, 250 and 255 ° C from the feed section to the 'measurement section of the barrel. The film die also had five temperature zones across its width, all of which were adjusted to provide a uniform temperature of 250 ° C. The extruder was operated at 21 rpm, resulting in its width, all of which were adjusted to provide a uniform temperature of 250 ° C. The extruder was operated at 21 rpm, resulting in a current draw or call of 28 amps, and a barrel pressure of 77.5 kg / cm2 (1100 psi).

EXAMPLE 1 An article for surface finish was developed having three identifiable layers comprising a non-woven web of an abrasive based on continuous filaments ("Hi-pro", Minnesota Mining and Manufacturing Company); a reinforcing fabric consisting of 16 x 16 plain woven canvas of 6.6 denier, 840 denier nylon yarns, weighing approximately 149 g / m2 (Highland Industries, Spartanburg, South Carolina) and a polymer layer of nylon 6 polymer. ("Ultramid", BASF Corporation). The nylon 6 polymer was introduced as a molten film processed from the single screw extruder, which was adjusted to provide a melting temperature of the 265 ° C. The flange of the die was placed at 5.1 cm (2 inches) above a pair of rotating, opposite pressure rollers. The first roller was a 20.3 cm (8 in) diameter chrome-plated molding roll. The second roller (rolling roller) was the same diameter as the first, and was fitted with a jacket roll cover coated with smooth surface polytetrafluoroethylene (Available under the trade designation "Edlon HST-2" from Edlon Roll Coverings of Avondale , Pennsylvania). Both rolls were described with water, by circulating cold water through them, to provide a surface temperature on each roll of 16 ° C. The coatable composition was a molten polymeric film which was applied to the back surface of the cloth opposite the nonwoven web just opposite the fastening point to provide a coating weight of the polymeric film of approximately 504 g / m2 and a cast layer approximately 0.51 mm thick. The rollers were operated at a surface speed of 1.3 meters per minute. The three layers were pressed together between the two rolls at a pressure of about 5.98 kg / cm 3 (85 psi) and the polymer was cooled and hardened after exposure to the cooled mold roll to provide a finished article.

EXAMPLE 2 An article for surface finish was made as in Example 1, except that the molten polymer layer was approximately 0.89 mm thick. The increased thickness of the polymer was achieved by decreasing the speed of the chromium-plated molding roller, from a surface velocity of 1.3 meters per minute to 0.65 meters per minute, to allow a thicker melt layer to accumulate on the surface. lining or backing of the fabric before compression of the layers between the rollers. An inspection of the articles of Examples 1 and 2 above was conducted by visual inspection and by the attempt to manually delaminate the layers thereof. Any delamination of the adhesive was considered unacceptable. The reinforcing fabric and the polymeric layer in the article of Example 1 were partially manually pulled, indicating that the thinner polymer layer in this article provided inadequate bonding. The article of Example 2, however, with its thicker polymeric layer could not be peeled off and therefore was considered acceptable for use in surface finishing applications.

EXAMPLE 3 An article for surface finishing comprising a non-woven web ("Scotch-Brite" High Strengh A-VFN, Minnesota Mining and Manufuring Company), and a reinforcing fabric consisting of a nylon 16 x 16 canvas ( as in Example 1). The two layers were stacked together and a layer of nylon 6 ("ultramid", BASF Corporation) was applied to the side of the stack by extrusion as in Example 1. The extruder was adjusted to produce a melting temperature of the 260 °. The chromium plated molding roller was rotated at a surface speed of 1.2 m / min. with the resulting molten polymeric layer deposited on cloth, with a thickness of approximately 0.55 mm. The three layers were consolidated by passing them between the two pressure rollers to between 0.11 and 0.32 kg / cm2 (1.6 and 4.6 psi). The resulting surface finish article was visually inspected and manual delamination of the layers attempted. The article was judged as well bonded, flexible, and had a flat, smooth polymer surface.

EXAMPLE 4 Another article was made for surface finishing, according to the procedure of Example 3, with the exception that the chromium-plated molding roll was replaced with a textured roller (plasma coating # 915, thickness 152.4 microns (0.006 inches ), 225 ± 5 rms, 58 Rc hardness commercially available from Plasma Coatings, Inc. of Waterbury, Connecticut) to create an exterior polymeric coating surface with a matte finish. Inspection of the finished article confirmed that it was well linked and flexible.

EXAMPLE 5 An article was developed for surface finishing first by mixing 72. 2 grams of a block polyfunctional isocyanate polymer ("Adiprene BL-16" Uniroyal Chemical Company, Inc.) with 31.2 grams of a 35% solution of methylene-dianiline (MDA) (available from BASF Corporation, Germany) in 2-ethoxyethanol acetate ("Arcosol PM Acétate" by Arco Chemical, Houston, Texas). A 0.08 mm (0.003 inch) polyethylene terephthalate (PET) film was coated on a 3% solution of poly (vinylalcohol) (PVA) in isopropanol (commercially available under the trade designation "Partall" No. 10, Worum Chemical Co., St. Paul, Minnesota) by brushing a uniform coating of the solution onto the film with a paint brush. The PVA solution served as a release agent. The solution was allowed to dry on the film overnight at ambient conditions. About half of the polyisocyanate / polyamine mixture was emptied onto the coated film and distributed on its surface. A section cut from 6.6 nylon 16 x 16 fabric was hand pressed into the polymer blend. The polymer mixture was easily extruded through the openings in the canvas with the application of moderate force. A section cut from the non-woven network material ("Scotch-Brite" High Strength A-VFN, Minnesota Mining and Manufacturing Company) was applied to the canvas and the composite article was cured in a convection oven at 121 ° C for 45 minutes. . After cooling to ambient conditions, the composite article was removed from the PET film and inspected by visual examination and manually delaminating the layers of the finished article. The polymeric layer had successfully united all the layers in the article and, the article was judged as a useful article for surface finishing.

EXAMPLE 6 Another article was made as in Example 5, except that two layers of canvas were placed on the polymeric film before adding it to the non-woven layer. The resulting article was well linked and judged to be appropriate for surface finishing applications.

EXAMPLE 7 Another article was elaborated according to the Example 5, except that a two-part unsaturated polyester resin was used instead of the polyisocyanate / polyamine mixture. The polymeric resin was commercially available under the trade designation "Castin Craft Clear Liquid Casting Resin and Catalyst" from ETI of Fields Landing, California. The polymer was cured at ambient conditions. An inspection of the resulting article indicated that it was well bonded and was suitable for surface finishing applications.

EXAMPLE CONTROL A An article was prepared for surface finishing as in Example 3, except that the stretch-resistant fabric reinforcement material was omitted. The resulting article was used as a control in the following comparative test.

PROOF OF BREAKING Comparative tests were conducted for the article of invention of Example 3 and Control Example A. Test specimens of 6.35 x 27.9 cm (2.5 x 11 inches) were cut from the articles of the previous examples. The specimens were then tested for breaking strength according to the Standard Elmendorf Break Test with a 6400 gram pendulum as described in Test Method D-1424 of the ASTM. The data are described in Table 1.

Table 1 1. It indicates that the experimental sample breaks at a force of the limits of the test apparatus.

The above data indicates that the sample of the invention had higher breaking strength than the control, thus indicating the additional strength given to the articles of the invention, by the inclusion of a porous reinforcing fabric combined by a polymeric layer comprising a flexible surface of low friction and portions that extend through the fabric, and encapsulate the fibers of the network.

RESISTANCE TO STRETCHING The stretch test was conducted for comparison of the article of the invention of Example 3 and Control Example A. Two test specimens were prepared, one for the Example and one for the Control A, each measuring approximately 2.5 x 17.8 cm (1 x 7 inches). Each of the specimens was mounted on a Sintech traction tester (available from MTS Systems of Minneapolis, Minnesota). The initial calibration was 12.7 cm (5 inches), and a full-scale load cell of 90.7 kg was used. (200 pounds). The speed of the cruzeta was adjusted to separate 2.54 cm (1 inch) per minute. The specimens were pulled until a load of 45.4 kg (100 pounds) was achieved. The elongated absolute elongations were measured and the results of those measurements are described in Table 2.

Table 2 The specimens were broken at a load of 38.6 kg (85 pounds).

The results in Table 2 establish that the low stretch values are obtained by the articles of the invention. The control article experienced significant elongation and stretching before breaking to load only 38.6 kg (85 pounds). The article of the invention of Example 3 had lower elongation and stretch, and was able to easily withstand 45.4 kg (100 pounds) of load without breaking.

FRICTION PROOF A determination of the coefficients of the static and kinetic friction was made for the articles of the invention of Examples 3 and 4 and for a control ("MAG 280", by Hermes Abrasives, Ltd, of Germany). The control (hereinafter "Control Example B") comprised a synthetic network coated with aluminum oxide abrasive and fixed to a cloth reinforcement. Specimens were cut by measuring 11.4 x 11.4 cm (4.5 x 4.5 inches) from the articles of Examples 3 and 4 and from Control Example B. ASTM test method 1894-90 was followed, "The static and friction kinetics of the plastic film and the sheet ". The comparative data are described in Table 3.

Table 3 The results shown in Table 3 show a lower coefficient of friction, desired, for the articles of the invention compared to the control, which lacked an oolimeric liner or support. The article of Example 4 gave slightly higher test values than those for the article of Example 3, showing that a matte finish on the polymeric layer as that of Example 4, will experience more friction in those applications in bands requiring the use of a platen. The coefficients of friction for Example 4, however, are still lower than those for Control B and are acceptable.

EXAMPLE 8 An article for surface finish was prepared comprising a non-woven web having a thickness of approximately 9 mm (0.35 inches) ("Scotch-Brite", "Clean and Finish" roller, type T, Minnesota Mining and Manufacturing Company), and a reinforcing fabric consisting of 16 x 16 nylon canvas (as in Example 1). The two layers were stacked together and a layer of nylon 6 ("Ultramid", BASF Corporation) was applied to the side of the stack by extrusion, as in Example 1. The extruder was adjusted to produce a melting temperature of the polymer. of 260 ° C. The molding roll was rotated at a surface speed of 1.2 m / min. resulting in a layer of molten polymer approximately 0.55 mm thick. The three layers were consolidated by passing them between the pressure rollers that rotate in the opposite direction, which applied pressures between 0.11 and 0.32 kg / cm2 (1.6 and 4.6 psi). The chromium plated molding roller was replaced with a textured roller (plasma coating # 915, thickness 152.4 microns (0.006 inches) 225 ± 50 rms, hardness 58 Rc, commercially available from Plasma Coatings, Inc., of Waterbury, Connecticut) to provide a matte finish to the polymeric layer. The resulting composite article was well linked and flexible. The article was cut into a strip measuring 12.7 cm x 6.55 m (5 inches x 2.58 inches) and worked in an endless band by conventional butt splicing. The band of Example 8 was comparatively tested in a commercially available surface-applied non-woven surface finish webbing product (FB "Scotch-Brite" type T surface-conditioning band, from Minnesota Mining and Manufacturing Company, hereby go ahead "Example Control C"). Control C comprised a nonwoven web which has been stitched with a needle in a canvas reinforcement. The fibers of the network were coated with a non-abrasive polyurethane coating. A layer of nylon 6 coated the back of the canvas and encapsulated the needle-woven fibers by connecting through the canvas. The polymer provided a smooth surface for the application of a platen against it. The band of Example 8 was mounted on a shock shoe having drive and actuated contact wheels, a support mix and a hand plate used to push the band against the work piece. A standard polishing compound was applied to the working surface of the band and, using the platen, the rotating band was pushed against a surface on a finished wooden piano cabinet as a top coating of lacquer for a period of approximately two minutes. . The treated wood was then inspected for the stripes. Control C was identically tested. A visual inspection and comparison of the polished surfaces with the previous bands revealed deep scratches on the surface treated with the Control C basted with a needle. The band of Example 8, however, provided a finished surface without objectionable scratches on the lacquer. The preferred embodiment of the invention has now been discussed and described in some detail. Those skilled in the art will appreciate that various changes and modifications in the written mode can be made without departing from the true spirit and scope of the invention, as defined in the following claims.

It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention. Having described the invention as above, property is claimed as contained in the following:

Claims (10)

1. An article for surface finish, characterized by: a three-dimensional non-woven raised web, of fibers having at least one larger surface, said fibers being joined to each other at their points of mutual contact; a porous reinforcing fabric resistant to re-stretching having first and second major surfaces, the first major surface of the fabric is placed on and along a larger surface of the nonwoven web; a layer comprising a flexible polymer coated on and coextensive with the second major surface of the fabric, the layer having an exposed surface of low pressure and portions extending through said reinforcing fabric by encapsulating the fibers along a surface largest in the network.

2. The article for surface finishing according to claim 1, characterized in that the fibers of the network are joined together at their points of contact with each other with an adhesive binder comprising a resinous thermosetting adhesive selected from the group consisting of phenolic resins, aminoplast resins having outstanding α, β-unsaturated carbonyl groups, urethane resins, epoxy resins, ethylenically unsaturated resins, acrylated isocyanurate resins, urea-formaldehyde resins, isocyanurate resins, acrylated urethane resins, acrylated epoxy resins, bismaleimide resins, epoxy resins modified with fluorine, and combinations thereof.

3. The article for surface finishing according to claim 2, characterized in that the binder further comprises abrasive particles selected from the group consisting of aluminum oxide, silicon carbide, alumina-zirconia, diamond, ceria, cubic boron nitride, garnet, and combinations thereof.

4. The article for surface finishing according to claim 1, characterized in that the fabric is a material selected from the group consisting of woven fabric, thermobonded fabric, fabric. knitted by stitches and cloth joined by stitches, and wherein the fabric includes a plurality of openings in it of about 0.10 mm2.

5. The article for surface finish according to claim 4, characterized in that the woven material comprises nylon 6.6 yarns and having 16 warp yarns and 16 fill yarns per 2.54 cm (1 inch), said yarns having a denier of about 840 denier and the fabric having a weight of approximately 149 g / m2.

6. The article for surface finishing according to claim 1, characterized in that the polymer is an extrudable thermoplastic material in molten form, selected from a group consisting of polyamide, polyester, polypropylene, polyethylene / vinyl acetate copolymer, acrylic copolymer / butadiene / styrene, ionomer, polyurethane, polyamide ether, and combinations thereof, and wherein said polymer has a hardness from about Shore 50 A to about Shore 80 D, and a thickness between about 0.175 mm and about 1.75 mm.

7. The article for surface finishing according to claim 1, characterized in that the polymer is a cured resin selected from the group consisting of polyurethane, polyester, epoxy resin, and combinations thereof.

8. A method for the manufacture of an article for surface finish, characterized by: the placement of a reinforcement fabric resistant to porous stretching, having first and second surfaces greater and adjacent to a larger surface of a three-dimensional, non-woven raised net, of fibers, such that said first major surface of the fabric substantially covers a larger surface of the network; the application of a coatable composition, so that a portion of the composition extends through the fabric to be contact and encapsulate the fibers along a larger surface of the network adjacent to the first major surface of the fabric, at time forming a coating having a surface exposed on and coextensive with the second major surface of the fabric; and hardening a coating composition to provide the article for surface finishing.

9. The method according to claim 8, characterized in that said application further comprises placing the composition on the second major surface of the fabric, and forcing a portion of the composition through the fabric to encapsulate the fibers along the length of the fabric. a larger surface of the net, while the rest of the composition is simultaneously smoothed on the second major surface of the fabric, to form the exposed surface; and wherein the forcing and smoothing are achieved by arranging the net, the fabric and the composition in successive layers, and passing said layers between rollers that rotate in the opposite direction, at least one of said rollers having a surface configured for Smooth the rest of the composition, forcing the rollers the composition through the fabric.

10. The method according to claim 8, characterized in that the application comprises placing the composition between the first major surface of the fabric and a larger surface of the network, to encapsulate the fibers along a larger surface of the network, while a portion of the composition is simultaneously forced through the fabric to the second major surface of the fabric, and the composition is smoothed over the second larger surface to form an exposed surface, and where forcing and smoothing are achieved by the arrangement of the net, the fabric and the composition in successive layers and passing said layers between the rollers that rotate in the opposite direction, at least one of said rollers having a surface that is configured to smooth the remainder of said composition, applying the rollers pressure the layers to force the composition through the fabric, and smoothing and softening the rest on the second gives larger surface. SUMMARY OF THE INVENTION The conformable surface finishing articles and a method for the manufacture of such articles are described. The articles comprise a three-dimensional non-woven raised fiber network (12),. a thick stretch-resistant reinforcing fabric (14) having first and second major surfaces, with the first major surface positioned along a larger surface of the net (12) and one layer (16) comprising a polymer coated on and coextensive with the second major surface of the reinforcing fabric and having a flexible, low-friction, exposed surface (17a) and portions (17b) that extend through the reinforcing fabric that encapsulates the fibers along the larger area of the network. The method comprises placing a porous reinforcing fabric (14) resistant to stretching, adjacent to a larger surface (12a) of a three-dimensional non-woven raised fiber network (12) by applying a coatable composition (16), so that a portion (17b) of the composition extends through the fabric to contact and encapsulate the fibers along the major surface (12a) of the network (12) while also forming an exposed surface substantially smooth, coated on and coextensive with the fabric, and hardening the composition.