MXPA00008277A - Abrasive article and method for making the same - Google Patents

Abstract

The present invention relates to an abrasive article. The abrasive article of the present invention contains an abrasive layer, a polyurethane structure bonded to the abrasive layer and a substrate bonded to the polyurethane structure. The present invention also involves a method for making said abrasive article.

Description

ABRASIVE PRODUCT AND METHOD FOR ITS MANUFACTURE TECHNICAL FIELD OF THE INVENTION The present invention relates to an abrasive product that can be used in the cleaning of a metal, glass or plastic surface in a clean room, and a method for manufacturing the abrasive product.

BACKGROUND OF THE INVENTION Different abrasive parts have been developed for use in cleaning and that incorporate a surface for scrubbing or scrubbing within a polyurethane or other polymeric sponge. U.S. Patent No. 3,414,928 discloses a sponge containing plastic or wire wool embedded in the surface of a polyurethane or polyacetate sponge. U.S. Patent No. 3,570,036 discloses a multi-layer polyurethane sponge, wherein the surface layers contain alternating polyurethane foil tapes of different textures. U.S. Patent No. 3,810,841 discloses that abrasives, as well as other additives such as soaps and detergents, can be integrally incorporated into a polyurethane sponge having at least one crosslinked layer for the output of the additives. In clean rooms, where semiconductors are produced, magnetic storage media or thin-film or semiconductor circuits are common • find cleaning problems. It is almost always necessary to clean metal, glass or plastic surfaces to eliminate metallic and other particles, and to eliminate organic and other residues. For example, after a metal pipe has been installed in a clean room, it is necessary to clean the inside surface of the metal pipe to remove metal particles resulting from ^ P 10 previous manufacturing, cutting or milling operations. In theory, products for cleaning metal, glass or plastic surfaces in clean rooms must meet certain criteria. These products must be hydrophilic and dissipate static. In particular, but not exclusively if used in clean rooms where semiconductors are produced, magnetic storage media or thin film circuits, these products must have ^ Very low counts of potentially destructive particles when released into deionized water, particularly particles of size larger than approximately 0.5 μ, and very low account for potentially deleterious ions when released in deionized water, particularly chlorine, fluorine, sodium, sulfate, sulfite or silicon. So far, none of the cleaning pads available for cleaning metallic, glass or plastic surfaces in clean rooms have met all these criteria.

SUMMARY OF THE INVENTION The present invention relates to an abrasive product containing an abrasive layer, a polyurethane film structure bonded to the abrasive layer and a substrate bonded to the structure of the polyurethane film. When the abrasive product is immersed in deionized water, it releases less than approximately 36.0 x 10 particles of a size • 10 greater than about 0.5 μ per square meter of the structure and less than about 2.5 parts per million of chloride, fluoride, sodium, sulfate, sulfite or silicon ions. The substrate used in the abrasive product is a open cell polyurethane foam, static dissipative, hydrophilic. Preferably, the structure of the polyurethane film contains two layers of film of B polyurethane that are bonded together, and one of the polyurethane films is bonded to the abrasive layer. From Most preferably, one of the layers of the polyurethane film is in a polyurethane with high melting point and the other layer of polyurethane film is a low melting polyurethane. The polyurethane film layer with low melting point is bonded to the abrasive layer and the layer of polyurethane with high melting point is bonded to the layer of polyurethane film with low melting point and the substrate is bonded to the polyurethane layer with a point of ^ high fusion. The present invention also relates to a method 5 for producing an abrasive product. The method includes joining a polyurethane film structure to an abrasive layer and bonding a substrate to the polyurethane layer. When the structure of the polyurethane film contains two layers of polyurethane film, the method includes the bonding F 10 of the first layer of the polyurethane film to the surface of an abrasive layer, the bonding of a second layer of a polyurethane film. polyurethane on the first layer of polyurethane film and the bonding of a substrate on the second layer of polyurethane film. Preferably, the first layer of polyurethane film is a polyurethane with a low melting point and the second layer of polyurethane film is a polyurethane with a high melting point.

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an abrasive product, specifically to an abrasive pad. The present invention also relates to a method for manufacturing the abrasive product. The abrasive product of the present invention has an abrasive layer, a structure of polyurethane film bonded to the abrasive layer and a substrate bonded to the polyurethane film structure. The abrasive layer used in the present invention contains abrasive particles. The individual abrasive particles can be selected from those commonly used in the abrasive art, however, the abrasive particles (size and composition) will be chosen based on the abrasive particles suitable for use in the present invention including hardness, compatibility with the part. of proposed work and particle size. The abrasive particles may be composed of natural abrasives or manufactured abrasives. Examples of natural abrasives include: diamond, corundum, emery, garnet, bubrstone [sic], quartz, stoneware, flint, quartzite, silica, feldspar, pumice and talc. Examples of the abrasives manufactured include: boron carbide, cubic boron nitride, fused alumina, ceramics, aluminum oxide, heat-treated aluminum oxide, alumina zirconia, glass, silicon carbide, iron oxides, tantalum carbide , oxide of serious, oxide of tin, titanium carbide, synthetic diamond, manganese dioxide, zirconium oxide and silicon nitride. The abrasive particles used in this invention have a particle size in the range from about 60 grit to about 1200 grit (grit = grain size).

As used herein, the term "abrasive particle" includes agglomerates of individual abrasive particles. An abrasive agglomerate is formed when a plurality of abrasive particles are agglomerated together with a binder to form a larger abrasive particle that can provide a specific particulate structure. The particles forming the abrasive agglomerate may contain more than one type of abrasive particle. The abrasive product of the present invention also ^ 10 contains a polyurethane film structure. The polyurethane film structure used in the present invention contains at least two layers of polyurethane film. The two layers of polyurethane film are bonded together and one of the layers is attached to the abrasive layer. It is possible to use any polyurethane polymer for the film layers and the polyurethane polymer used for each of the layers k may be the same or different. Preferably, one of the film layers is a polyurethane layer with a point of low fusion. As used herein, the term "low melting point polyurethane layer" means that it melts at a lower temperature and the term "high melting point polyurethane layer" means that it melts at a higher temperature. An example of a polyurethane with low melting point that can be used in the present TO. invention is PURO Hl, which is available from Adhesive Films, Inc., 4 Barnett Road, Pine Broo, NJ 07058. An example of a • Polyurethane with high melting point that can be used in the present invention is PT6100S, which is available from Deerfield Urethane Inc., Route 5 & 10, Box 186, South Deerfield, MA 01273. Polyurethane with low melting temperature is bonded to the abrasive layer and polyurethane with high melting point joins the polyurethane at low melting temperature. ^ 10 The substrate used in the present invention is an open cell polyurethane foam, which dissipates static, hydrophilic and joins the structure of the polyurethane film. The polyurethane foam used in the present invention is a material that dissipates static in a natural way, that is, it has a safe electrostatic charge (ESD). The polyurethane foam material has a surface resistance of 10 to • approximately 108 ohs / cm2. In general, materials that have less surface resistance than approximately 10 12 ohms / cm2 are considered safe ESD. Materials that have surface resistances greater than about 10 12 olims / cm2 require treatment, such as processing with surfactants, to reduce surface resistance to acceptable levels. An example of an open cell, static dissipative, hydrophilic polyurethane foam that can be used in this invention is Ultra SOLV, which is commercially available from Ilshire Technologies, Inc. The abrasive product of the present invention 5 is prepared by bonding a polyurethane film structure to an abrasive layer and then bonding a substrate to the polyurethane film structure. When the polyurethane film structure contains a polyurethane layer with a low melting point and a polyurethane layer with a high melting point, the abrasive product is prepared by bonding the low melting point polyurethane layer to the abrasive layer, joining the polyurethane film with high melting point to the polyurethane film with low melting point and then attaching a substrate to the polyurethane film with high melting point. The abrasive product of the present invention is preferably a pad having a size from about 1"x 2" to about 10"x 10". The pad generally has parallel sides having a plate-like shape defining two broad surfaces, two long sides and two short ends. The abrasive product can be a triangular pad, in the form of a rod or other shapes depending on the applications. The entire abrasive product or components of the abrasive product, as in the substrate, can be washed, as described in U.S. Patent No. 5,460,655, the disclosure of which is incorporated herein by reference, to minimize the release of potentially destructive particles, particularly particles of a size greater than about 0.5 μ, and to minimize the potential release of potentially deleterious ions, particularly chloride, fluoride, sodium, sulfate, sulfite or silicon ions. Specifically, the product is washed so that when the product is immersed in deionized water it releases less than about 36.0 x 10 particles of a size greater than about 0.5 μ per square meter of apparent surface area of the product and less than about 2.5 parts per second. million chloride, fluoride, sodium, sulfate, sulfite or silicon ions. The washing process not only reduces the number of particles released from the product and reduces residual chemical contaminants but also reduces the amount of total non-volatile waste (TNVR) that would be released from the product during use. In general, the laundry process uses a detergent suspended in different molar ratios, such as sodium oxalate, sodium oleate, sodium perchlorate and sodium peroxydisulfate. The detergent solution contains no more than 0.002% of ions including chloride, bromide, sodium and the like. Optionally, the detergent can include oxidants, buffer solutions and moderate acid to optimize the material for specific applications. The preferred temperature range for the laundry process is between about 104 ° F (40 ° C) and about 149 ° F (65 ° C). The complete article can be washed after the final assembly of the components or each of the components of the product, particularly the abrasive layer and the substrate, can be washed individually before • 10 of the assembly of the product. For example, and not as a limitation, the examples of the present invention will now be given.

Example 1 - Construction of an abrasive pad 15 Micro-Mesh, an abrasive sheet marketed by Micro-Surface Finishing Products, Inc., 1217 West Street, Wilton, Iowa, was placed on a clean surface with one side A) abrasive down. The abrasive sheet contained silicon carbide as abrasive particles with a particle size of 180 grit. Silicon carbide? [sic] PURO Hl, a low melting polyurethane film, marketed by Adhesive Films, Inc. 4 Barnett Road, Pine Brook, NJ 07058, was deposited on the upper side of the fabric of the abrasive sheet. Then, PT6100S, a high melting polyurethane film, marketed by Deerfield Urethane, Inc., Route 5 & 10, Box 186 ,, South Deerfield, MA, was placed in the • top of the polyurethane film with low melting point. Then, four 3.5-inch by 5 4.5-inch movies were cut. The four films were then placed on a hot plate at the controlled temperature of 360 ° F with the abrasive side facing the hot plate. A weight of 10 pounds measuring 4 inches by 5 inches was then placed on top of the hot plate. 10 After 45 seconds, the laminate was removed from the hot plate and cut in one piece with the dimension of 3 inches by 4 inches. Laser analysis .Ablation ICP-MS was performed on the pad by Elemental Research Inc., 309-267 West Esplanade, North Vancouver, British Columbia, Canada. The Laser Analysis .Ablation ICP-MS is where a layer of material is removed by laser and vaporized. The material goes to a vacuum chamber and is analyzed by mass spectroscopy. The results of the analysis are shown in Table 1 below. twenty Table 1 • Lithium < 0.01 Beryllium 0.17 Boron 0.2 Sodium 11.0 Magnesium 40.0 Aluminum 170 Sulfur 12.0 Calcium Do not Scandio < 0.1 Titanium 52.0 Vanadium 15.0 Chrome 19.0 Manganese 6.5 Iron 180.0 Cobalt 0.18 Nickel 9.10 Copper 11.0 Zinc < 0.01 Gallium < 0.01 Germanium 0.60 Arsenic 0.65 Selenium < 1 • Bromine 0.08 Rubidium 0.06 Strontium 1.70 Itrium 0.32 Zirconium 2.70 • Niobium < 0.01 Molybdenum 0.51 Ruthenium < 0.01 Rhodium < 0.01 Palladium < 0.01 Silver < 0.01 Cadmium 0.07 Indian < 0.01 Tin 0.22. Antimony 0.05 Tellurium 0.37 Iodine 0.03 Cesium < 0.01 Barium 6.0 Lantano 0.33 • Cerium 0.45 Praseodymium 0.16 Neodymium < 0.01 Europio < 0.01 Samarium 0.05 Gadolinium 0.11 • Terbium 0.04 Disprosium 0.03 Holmium 0.03 Erbium 0.06 Thulium 0.04 Iterbium 0.10 Lutetium 0.02 Hafnium 0.03 Tantalum 0.02 Tungsten < 0.01 Renio < 0.01 Osmium < 0.01 Iridium < 0.01 Platinum 0.04 • Gold < 0.01 Mercury 0.01 Thallium < 0.01 Lead 3.80 Bismuth 0.07 Thorium < 0.01 • Uranium < 0.01 Is the entire pad washed after assembly or are components washed before assembly? The component (only the foam) is washed before assembly.

Example 2: Comparison with Scotchbrite® Some Scotchbrite® pads were subjected to the Ablation ICP-MS laser analysis. The results are shown below in Table 2. 10 Table 2 • Gl-PAD-7447a Gl-PAD-7447b Gl-PAD-7447c Lithium 32.0 77.0 59.0 Beryllium 2.40 3.20 2.30 Boron 12.0 20.0 14.0 Sodium 520 390 430 Magnesium 2200 3200 2700 Aluminum c p. pr cmp. pr cmp. pr Silicon 3300 5300 4300 Sulfur 32.0 35.0 30.? ' Calcium 56000 65000 62000 Scandium 2.4 4.6 2.0 Titanium 5900 9200 9000 Vanadium 16.0 42.0 46.0 Chrome 530 310 320 Manganese 590 830 710 Iron 6300 8500 8500 Cobalt 0.71 1.50 1.40 Nickel 9.90 13.0 17.0 Copper 29.0 23.0 31.0 Zinc 15.0 19.0 16.0 Gallium 270 51.0 37.0 Germanio 10.0 16.0 15.0 Arsenic 3.10 4.80 20.0 Selenium < 0.01 < 0.01 < 0.01 Bromine 0.10 0.10 0.07 Rubidium 6.20 7.50 5.10 Strontium 170 150 130 Itrium '79.0 99.0 31.0 Zirconium 390 990 480 Niobium 15.0 13.0 4.90 Molybdenum 9.60 6.50 6.30 Ruthenium 0.02 0.02 < 0.01 Rhodium 0.08 0.05 < 0.01 Palladium 2.10 2.70 1.70 Silver 0.46 1.50 0.52 Cadmium 0.21 0.17 0.35 Indian 0.23 0.18 0.41 Tin 18.0 6.90 6.40 Antimony 3.30 3.20 2.80 Tellurium < 0.01 0.19 0.37 Iodine < 0.01 < 0.01 < 0.01 »- ^ - ^ * ^ M ^ .¿w ^^ Cesium 0.07 0.16 0.18 Barium 63.0 89.0 65.0 Lantano 63.0 62.0 47.0 Cerium 210 260 150 Praseodymium 14.0 28.0 14.0 Neodymium 54.0 81.0 46.0 Europium 3.30 4.0 4.0 Samarium 14.0 17.0 12.0 Gadolinium 34.0 43.0 26.0 Terbium 2.40 3.40 2.10 Disprosio 19.0 29.0 13.0 Holmio 3.70 5.50 3.0 Erbium 11.0 17.0 7.60 Tulio 1.90 3.40 1.40 Iterbio 16.0 26.0 16.0 Lutecio 1.60 3.0 1.20 Hafnium 12.0 39.0 15.0 Tantalum 0.09 0.86 0.33 Tungsten 0.41 1.80 0.71 Renio 0.04 0.09 0.16 -... faith .- "ai JU¡t¿t * t i Osmio < 0.01 0.17 < 0.01 Iridium < 0.01 < 0.01 0.03 • Platinum < 0.01 < 0.01 0.11 Gold < 0.01 < 0.01 0.05 Mercury 0.10 0.08 0.22 Thallium < 0.01 < 0.01 0.06 Lead 12.0 23.0 15.0 Bismuth 0.49 0.71 4.0 Thorium 50.0 82.0 50.0 Uranium 12.0 41.0 12.0 Results: As seen in the results of Tables 1-2, the abrasive article of the present invention contains fewer metal ions than the Scotchbrite® 5 pads that were tested.

Claims (12)

1. CLAIMS P 1. An abrasive product consisting of: an abrasive layer; 5 a polyurethane film structure bonded to the abrasive layer; and a substrate attached to the structure of the polyurethane film, wherein when the product is immersed in deionized water it releases less than about 36.0 x 10 lv 10 particles of a size greater than about 0.5 μm per square meter of the structure and less than approximately
2. 2. 5 parts per million chloride, fluoride, sodium, suflate, sulfite or silicon ions. 2. The product of claim 1, wherein the substrate is an open cell, dissipative, hydrophilic, polyurethane foam.
3. 3. The product of claim 1, wherein the structure of the polyurethane film contains at least two layers of polyurethane film, which are • attached 20 yes, and one of which is attached to the abrasive layer.
4. 4. The product of claim 3, wherein one layer of polyurethane film contains a high melting polyurethane and the other layer of polyurethane film consists of a low melting polyurethane.
5. 5. The product of claim 4, wherein the low melting polyurethane film layer is bonded to the abrasive layer, the polyurethane ^ High melt is bonded to the low melting polyurethane film layer and the substrate is bonded to the layer 5 high-melting polyurethane film.
6. The product of claim 1, wherein the abrasive layer contains abrasive particles with a size from about 60 grit to about 1200 grit.
7. 7. An abrasive product comprising: w 10 an abrasive layer; a layer of low melting polyurethane bonded to the abrasive layer; a high melting polyurethane layer bonded to the low melting polyurethane layer; and a substrate attached to the high melting point polyurethane layer, wherein the product when immersed in water or deionized releases less than about 36.0 x 10 j particles larger than 0.5 μ per square meter of the structure and less than about 2.5 parts per million 20 of chloride, fluoride, sodium, sulfate, sulfite or silicon ions.
8. 8. The method of claim 7, wherein the substrate is an open cell polyurethane foam, dissipative from static, hydrophilic.
9. The method of claim 7 further comprises the steps of attaching a first layer of polyurethane film to the surface of the abrasive, joining a second layer of polyurethane film to the first layer of polyurethane film, wherein the first and Second layers of the polyurethane film define the structure of the polyurethane film.
10. The method of claim 9, wherein the first layer of polyurethane film is made of a low melting point polyurethane and the second layer of polyurethane is made of a high melting point polyurethane.
11. 11. A method for producing an abrasive product, the method comprising the steps of: a) bonding a low melting point polyurethane layer to an abrasive layer; b) attaching a high melting point polyurethane layer to the low melting point polyurethane layer; and c) attaching a substrate to the high melting point polyurethane, wherein the product releases less than about

    36. 0 x 10 particles of a size greater than about 0.5 μm per square meter of the structure and less than about 2.5 parts per million of chloride, fluoride, sodium, sulfate, sulfite or silicon ions.
12. 12. The method of claim 11, wherein the substrate is an open cell, dissipative, hydrophilic, polyurethane foam.