EP0546831A2 - Abrasif revêtu contenant une couche en résine époxy appliquée en base aqueuse - Google Patents

Abrasif revêtu contenant une couche en résine époxy appliquée en base aqueuse Download PDF

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Publication number
EP0546831A2
EP0546831A2 EP92311283A EP92311283A EP0546831A2 EP 0546831 A2 EP0546831 A2 EP 0546831A2 EP 92311283 A EP92311283 A EP 92311283A EP 92311283 A EP92311283 A EP 92311283A EP 0546831 A2 EP0546831 A2 EP 0546831A2
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Prior art keywords
coat
epoxy resin
make coat
backing
coated abrasive
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EP92311283A
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German (de)
English (en)
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EP0546831A3 (en
EP0546831B1 (fr
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Chong Soo c/o Minnesota Mining and Lee
Scott J. C/O Minnesota Mining And Buchanan
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3M Co
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Minnesota Mining and Manufacturing Co
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24D—TOOLS FOR GRINDING, BUFFING OR SHARPENING
    • B24D3/00—Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents
    • B24D3/02—Physical 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
    • B24D3/20—Physical 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
    • B24D3/28—Resins or natural or synthetic macromolecular compounds
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24D—TOOLS FOR GRINDING, BUFFING OR SHARPENING
    • B24D3/00—Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24D—TOOLS FOR GRINDING, BUFFING OR SHARPENING
    • B24D3/00—Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents
    • B24D3/34—Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents characterised by additives enhancing special physical properties, e.g. wear resistance, electric conductivity, self-cleaning properties
    • B24D3/342—Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents characterised by additives enhancing special physical properties, e.g. wear resistance, electric conductivity, self-cleaning properties incorporated in the bonding agent
    • B24D3/344—Physical features of abrasive bodies, or sheets, e.g. abrasive surfaces of special nature; Abrasive bodies or sheets characterised by their constituents characterised by additives enhancing special physical properties, e.g. wear resistance, electric conductivity, self-cleaning properties incorporated in the bonding agent the bonding agent being organic

Definitions

  • This invention relates to a coated abrasive having a plurality of abrasive grains bonded to a backing by means of one or more binders, in particular a binder formed from an epoxy resin that is coatable from water.
  • Coated abrasives comprise a backing having abrasive grains bonded thereto by one or more binders.
  • These binders typically comprise a glutinous or resinous adhesive, and may optionally contain one or more additives.
  • resinous adhesives include epoxy resins, phenolic resins, urethane resins, acrylate resins, and aminoplast resins.
  • additives include fillers, grinding aids, wetting agents, dispersing agents, pigments, coupling agents, and dyes.
  • a grinding aid is included in the binder to improve the abrading characteristics of the coated abrasive. It is believed that the grinding aid has a significant effect on the chemical and physical processes of abrading, thereby providing improved performance.
  • Minnesota Mining and Manufacturing Company of St. Paul Minnesota has manufactured Regalite Polycut coated abrasives that contain an overcoating of an epoxy resin with a potassium tetrafluoroborate grinding aid dispersed in the epoxy resin.
  • the binders previously referred to are typically applied by coating from an organic solvent. There are several advantages in coating a resinous binder from an organic solvent, rather than from water.
  • the lower surface tension of organic solvents typically provides better wetting and better adhesion, lower viscosities, and better dispersions of the additives.
  • U.S. Patent No. 4,396,657 discloses a saturant for impregnating the multifilament yarns of a stitchbonded coated abrasive backing comprising an epoxy resin, a dicyandiamide, blocked isocyanates, and/or imidazole curing agents.
  • the epoxy resin is capable of being coated from water.
  • U.S. Patent No. 3,615,303 discloses a treatment for the backing of a coated abrasive.
  • the treatment referred to as an intermediate layer, comprises an epoxide resin mixture based on (a) 4,4'-dihydroxydiphenyl-2, 2-propane (Bisphenol A), (b) an epoxide resin based on Bisphenol A internally plasticized by a reaction with castor oil, (c) carbamic acid alkyl esters, and (d) a curing agent.
  • This epoxide resin is capable of being coated from water.
  • This invention provides a coated abrasive article having a plurality of abrasive grains bonded to a backing by means of one or more binders.
  • the binders can be formed from an epoxy resin that is capable of being coated from water.
  • the coated abrasive comprises:
  • a grinding aid in the size coat or supersize coat or both size coat and supersize coat in addition to the epoxy resin capable of being coated from water, curing agent, and emulsifier.
  • the coated abrasive comprises:
  • Epoxy equivalent weight is the average molecular weight of the resin divided by the average number of epoxy functional groups per molecule.
  • the purpose of the curing agent is to initiate polymerization of the epoxy resin, which is the resinous adhesive in the binder.
  • the purpose of the grinding aid is to improve the abrading characteristics of the coated abrasive. Examples of typical grinding aids include potassium tetrafluoroborate and cryolite.
  • the weight ratio of the epoxy resin to the grinding aid ranges from about 10 to 85 parts epoxy resin to about 15 to 85 parts grinding aid.
  • the coat containing the epoxy resin and the grinding aid be the outermost coat of the coated abrasive article in order to position the grinding aid in direct contact with the workpiece being abraded.
  • FIG. 1 is a side view of a coated abrasive made according to the present invention.
  • FIG. 2 is a side view of a coated abrasive made according to the present invention.
  • epoxy resin refers to epoxy resins capable of being coated from water unless indicated otherwise;
  • epoxy dispersion refers to a dispersion containing an epoxy resin, an emulsifier for the epoxy resin, a curing agent for the epoxy resin, and water.
  • FIGS. 1 and 2 depict embodiments wherein at least one of the make coat, size coat, or optional supersize coat is formed from a composition comprising an epoxy resin, an emulsifier for the epoxy resin, a curing agent, and water. It is also acceptable for the make coat and size coat, make coat and supersize coat, size coat, and supersize coat, or make coat, size coat and supersize coat to be formed from the epoxy composition. In some instances, it is preferred that the size coat or supersize coat or both coats contain, in addition to the epoxy resin, the emulsifier for the epoxy resins, and the curing agent, a grinding aid. Grinding aids are particularly useful in coarse grade abrasives that are used for abrading metals.
  • coated abrasive 10 comprises a backing 12 and a plurality of abrasive grains 14 supported by and adherently bonded to backing 12 by means of a binder 16, hereafter referred to as the make coat. Overlying abrasive grains 14 and make coat 16 is a binder 18, hereafter referred to as the size coat. Size coat 18 further secures abrasive grains 14 to backing 12.
  • the size coat can be prepared from a composition comprising an epoxy resin, an emulsifier for the epoxy resin, a curing agent, a grinding aid, and water. In this particular embodiment, the size coat is the outermost coating of the coated abrasive, and it can directly contact the workpiece being abraded.
  • coated abrasive 20 comprises a backing 22 and a plurality of abrasive grains 24 supported by and adherently bonded to backing 22 by means of a binder 26, hereafter referred to as the make coat. Overlying the abrasive grains 24 and make coat 26 is a binder 28, hereinafter referred to as the size coat. Coated abrasive 20 further comprises supersize coat 30 overlying size coat 28.
  • Supersize coat 30 can be formed from a composition comprising an epoxy resin, an emulsifier for the epoxy resin, a curing agent, a grinding aid, and water.
  • the supersize coat is the outermost coating of the coated abrasive, and it can directly contact the workpiece being abraded. It is also acceptable for both size coat 28 and supersize coat 30 to be formed from a composition comprising an epoxy resin, an emulsifier for the epoxy resin, a curing agent, a grinding aid, and water.
  • Backings 12 and 22 are preferably selected from materials that can be formed into sheets, such as paper, cloth, polymers, nonwoven materials, e.g., an open, porous non-woven web, vulcanized fibre, combinations thereof, and treated versions thereof.
  • Abrasive grains 14 and 24 are preferably selected from such abrasive materials as silicon carbide, fused aluminum oxide, heat-treated aluminum oxide, garnet, alumina zirconia, ceramic aluminum oxide, diamond, cubic boron nitride, and combinations thereof.
  • Make coats, size coats, and supersize coats not formed from the epoxy dispersion can be formed from a glutinous or resinous adhesive, and they may also contain other additives.
  • resinous adhesives suitable for preparing make coats, size coats, and supersize coats include phenolic resins, urea formaldehyde resins, epoxy resins not coatable from water, urethane resins, acrylate resins, aminoplast resins, melamine resins, and mixtures thereof.
  • Additives suitable for make coats, size coats, and supersize coats include wetting agents, grinding aids, fillers, coupling agents, dyes, pigments, antistatic agents, and combinations thereof.
  • Epoxy resin contains an oxirane ring, i.e., The epoxy resin is polymerized or cured by means of a ring opening mechanism.
  • Epoxy resins suitable for this invention must be coatable from water.
  • Epoxy resins suitable for this invention include both monomeric epoxy compounds and polymeric epoxy compounds.
  • the epoxy resins may vary greatly in the nature of their backbones and their substituent groups; for example, their backbones can be aliphatic, cycloaliphatic, or aromatic.
  • a representative example of an aliphatic epoxy resin is diglycidyl ether of a polyoxyalkylene glycol.
  • cycloaliphatic epoxy resins include epoxycyclohexanecarboxylates, e.g., 3,4-epoxy-2-methylcyclohexylmethyl 3,4-epoxycyclohexanecarboxylate, and 3,4-epoxy-2-methylcyclohexylmethyl 3,4-epoxy-2-methylcyclohexanecarboxylate.
  • aromatic epoxy resins include 3,3-bis[4-(2,3-epoxypropoxy)-phenyl]propane (diglycidyl ether of bisphenol A), N,N,N,N'-tetraglycidyl-4,4'-diaminodiphenylmethane, and triglycidyl-p-aminophenol.
  • the backbone of the epoxy resin can be modified with organic substituents, such as, for example, a urethane epoxy resin.
  • the addition of the urethane group to the epoxy backbone can increase the flexibility of the resulting cured binder. In some instances, e.g., with respect to fine grade coated abrasive products, flexibility provides some advantages.
  • the preferred epoxy resin for the size coat or supersize coat is a diglycidyl ether of bisphenol A.
  • n can range from 0 to 10, but it preferably ranges from 1 to 4. As the value of n increases, the viscosity of the resin also increases. If the viscosity of the resin is too high, it will be difficult to apply as a coating.
  • Another type of epoxy resin is a novolac resin, which is illustrated below.
  • n' can range from 0 to 4, preferably from about 0.2 to 2. The higher values of n' result in a more viscous resin.
  • the epoxide equivalent weight (EEW) can range from 160 to 700. For the make coat, it is required that this equivalent weight be less than about 500, preferably in the range of about 165 to about 350 and most preferably in the range of about 180 to about 250.
  • a make coat that is formed from an epoxy composition having a higher EEW tends to solidify too fast. Excessively rapid solidification tends to result in poor adhesion of the abrasive grains to the make coat.
  • the make coat formed from the epoxy dispersion having the higher EEW has to be heated prior to the application of the abrasive grains to inhibit solidification of the make coat.
  • steam can be applied to the surface of the make coat to resoften the surface to inhibit solidification of the make coat to allow the abrasive grains to adhere properly.
  • the preferred EEW for a size coat or supersize coat formed from an epoxy dispersion is typically in the range of 200 to 700.
  • the pH of the epoxy resin by itself, can range from about 3 to about 8.5, preferably from about 3.5 to about 8.
  • Examples of commercially available epoxy resins suitable for this invention include the CMD series or "EPI-REZ" series epoxy resins from Rhone-Poulenc, Louisville, Kentucky.
  • the epoxy resin is dispersed in water with the aid of an emulsifier to form a dispersion, hereafter referred to as "epoxy dispersion".
  • the epoxy dispersion will contain from 30 to 90% solids, preferably about 45% to about 75% solids.
  • Emulsifiers that are suitable for preparing the epoxy dispersion include cationic, anionic, and nonionic emulsifiers. Cationic dispersions result in a positive charge on the resin particle or on the emulsifier, whereas anionic dispersions provide negative charges. Nonionic dispersions do not have charges associated with them. Nonionic emulsifiers are preferred.
  • emulsifiers suitable for this invention include sodium dioctyl sulfosuccinate, alcohol ethoxylates, and alcohol alkoxylates.
  • a curing agent can then be added to the epoxy dispersion. The purpose of the curing agent is to initiate the polymerization of the epoxy resin after the composition has been coated so that a thermosetting, chemical resistant polymer will be formed.
  • the epoxy dispersion contains from about 0.01 to about 30% by weight curing agent, preferably 1 to 5% by weight curing agent, based upon the weight of the epoxy resin.
  • curing agents suitable for the epoxy resins of this invention include amines, such as polyamidoamines and tertiary amines, amides such as dicyandiamide, mercaptans, and imidazoles, such as 2-methyl imidazole, 2-phenyl imidazole, and 2-ethyl-4-methylimidazole.
  • the preferred curing agent is 2-ethyl-4-methylimidazole, commercially available from Air Products Company under the trade designation "EMI-24". It is also preferred that the curing agent be dispersed in water prior to being added to the epoxy dispersion.
  • Other useful curing agents for the epoxy resin include urea-formaldehyde resins and melamine formaldehyde resins.
  • urea-formaldehyde resins examples include "DURITE AL 8401" and “DURITE AL 8405" resins, available from the Borden Chemical Co.
  • the weight ratio of epoxy resin to urea-formaldehyde resin typically ranges from 40 to 80 parts epoxy resin to 20 to 60 parts urea-formaldehyde resin.
  • the epoxy dispersion for preparing the size coat or supersize coat also contain a grinding aid, particularly for coated abrasives containing coarse to medium grade abrasive grains.
  • grinding aids are particulate materials, the addition of which to a coated abrasive article enhances the abrading performance of the coated abrasive article. It is believed that the grinding aid exercises a significant effect on the chemical and physical processes encountered during abrading, thereby providing improved performance. In particular, it is believed that the grinding aid will carry out one or more of the following:
  • Classes of grinding aids suitable for this invention include waxes, organic halide compounds, halide salts, metals, and alloys of metals.
  • Organic halide compounds typically break down during abrading and release a halogen acid or a gaseous halide compound.
  • Examples of organic halides include chlorinated waxes, such as tetrachloronaphthalene, pentachloronaphthalene; and polyvinyl chloride. Chlorinated waxes can also be considered to be waxes.
  • halide salts include sodium chloride (NaCl), potassium chloride (KCl), potassium fluoroborate (KBF4), ammonium cryolite (NH4)3AlF6, cryolite (Na3AlF6), and magnesium chloride (MgCl2).
  • metals include tin, lead, bismuth, cobalt, antimony, cadmium, iron, and titanium.
  • Other grinding aids include sulfur and organic sulfur compounds, graphite, and metallic sulfides. Combinations of grinding aids can be used, and in some instances may produce a synergistic effect.
  • the preferred grinding aid for stainless steel is potassium tetrafluoroborate.
  • the preferred grinding aid for mild steel is cryolite.
  • the ratio of epoxy resin to grinding aid preferably ranges from about 10 to about 85, preferably about 15 to about 60, parts by weight epoxy resin to about 15 to about 85, preferably about 40 to about 85, parts by weight grinding aid.
  • a dispersing agent to the epoxy dispersion.
  • a dispersing agent for example, if potassium tetrafluoroborate is used as a grinding aid, it is preferred to add a dispersing agent to the epoxy dispersion to lower its viscosity.
  • cryolite is used as a grinding aid, it is not always necessary to add a dispersing agent to the epoxy dispersion.
  • Representative examples of commercially available dispersing agents suitable for this invention include fluorosurfactants having the trademarks of "FLUORAD", available from Minnesota Mining and Manufacturing Company, St. Paul, Minnesota, and "AEROSOL OT", available from Rohm & Haas Company.
  • the concentration of the dispersing agent is less than 2%, based on the weight of the epoxy resin.
  • the viscosity of the composition containing epoxy resin, emulsifier, curing agent, and water should be less than 10,000 centipoises, preferably less than 5,000 centipoises. If the viscosity is greater than 30,000 centipoises, it is difficult to process the composition in the manufacture of a coated abrasive.
  • resins can also be included in the epoxy dispersion.
  • phenolic resins which can co-react with the epoxy resin, can be included.
  • urethanes and rubber compounds can be added to the dispersion in order to improve the toughness of the cured epoxy resin.
  • Latexes can be added to the epoxy dispersion to increase the flexibility of the cured binder.
  • additives such as dyes, defoamers, pigments, fillers, and coupling agents, can be used in the composition for preparing the size coat or supersize coat of this invention.
  • a defoamer to remove unwanted air bubbles.
  • make coats 16 and 26 and size coat 28 can also be prepared from compositions comprising an epoxy resin coatable from water, an emulsifier for the epoxy resin, a curing agent, a grinding aid, and water.
  • the make coat of the coated abrasive article utilizes conventional resole phenolic resin containing calcium carbonate as a filler
  • the size coat of the coated abrasive article utilizes a conventional resole phenolic resin containing cryolite as a grinding aid
  • the coated abrasive article utilizes a supersize coat made from a composition containing a diglycidyl ether of bisphenol A epoxy resin, nonionic emulsifier, water, an imidazole curing agent, potassium tetrafluoroborate grinding aid, and "AEROSOL OT" dispersing agent. It is preferred that the grinding aid be in the outermost coat of the coated abrasive so that it can be in direct contact with the workpiece being abraded.
  • the epoxy dispersion Once the epoxy dispersion has been applied to the coated abrasive article, it can be heated to bring about polymerization of the epoxy resin. Heating is typically conducted for a period of from about 10 to about 250 minutes, preferably from about 20 to about 50 minutes, at temperatures from about 80 to about 130°C, preferably from about 105 to about 115°C.
  • the abrading performance of a coated abrasive containing an epoxy resin of this invention is significantly improved over that of a coated abrasive containing an epoxy resin coated from an organic solvent, with everything else being equal. Furthermore, it has been found that the performance of the coated abrasive containing the epoxy resin of this invention does not decrease over time as rapidly as does that of a coated abrasive containing an epoxy resin coated from an organic solvent.
  • the advantages of utilizing the epoxy resin of this invention rather than epoxy resins coated from an organic solvent include reduction of pollution, greater ease of cleaning from the coating station, and greater ease of roll coating onto the surface of the coated abrasive.
  • the backing was a polyester cloth with a four over one weave containing a phenolic/latex saturant, backsize coat, and presize coat.
  • the make coat contained 48% by weight resole phenolic resin and 52% by weight calcium carbonate as a filler.
  • the make coat (83% solids) was applied to the backing at a wet weight of approximately 190 g/m2.
  • fused alumina abrasive grain grade 80
  • ceramic aluminum oxide abrasive grain was electrostatically coated onto the make coat at a weight of 460 g/m2.
  • the resulting article was cured for 15 minutes at 79°C and then for 60 minutes at 96°C.
  • a size coat containing resole phenolic resin (32% by weight), iron oxide (2% by weight), and cryolite (66% by weight) was applied over the abrasive grains at a weight of about 250 g/m2.
  • the size coat contained approximately 76% solids.
  • the resulting article was cured for 35 minutes at 66°C and then for 75 minutes at 88°C.
  • the coated abrasive article was finally cured for 10 hours at 100°C.
  • a supersize coat was applied over the size coat and then cured for 30 minutes at 100°C.
  • Table I The formulation of the supersize coat of the coated abrasive article in each example is set forth in Table I.
  • the coated abrasive article of each example was then converted into 7.6 cm by 335 cm endless abrasive belts.
  • Two belts from each example were tested on a constant load surface grinder.
  • a pre-weighed, 304 stainless steel workpiece approximately 2.5 cm by 5 cm by 18 cm was mounted in a holder, positioned vertically, with the 2.5 cm by 18 cm face confronting approximately 36 cm diameter 60 Shore A durometer serrated rubber contact wheel with one on one lands over which was entrained the coated abrasive belt.
  • the workpiece was then reciprocated vertically through a 18 cm path at the rate of 20 cycles per minute, while a spring-loaded plunger urged the workpiece against the belt with a load of 6.7 kg as the belt was driven at about 2,050 meters per minute.
  • coated abrasive articles that contained both epoxy resins that were coated from water and cryolite did not perform as well as coated abrasive articles that contained both epoxy resins that were coated from solvent and cryolite.
  • the supersize coats for Examples 5 and 6 were prepared, it was noted that there was excessive foaming. This foaming can be reduced with the addition of an appropriate anti-foaming agent.
  • Example 7 and Comparative Example D illustrate how a dispersing agent aids in the dispersion of potassium tetrafluoroborate grinding aid.
  • the mixture formed a thick paste.
  • Coated abrasive discs were prepared according to the following procedure.
  • a conventional calcium carbonate filled resole phenolic resin was applied to 0.76 mm thick vulcanized fibre backing sheet to form a make coat.
  • grade 50 heat treated aluminum oxide abrasive grains were drop coated onto the make coat.
  • a blend of 30% ceramic aluminum oxide abrasive grains (grade 50) and 70% heat treated aluminum oxide abrasive grains (grade 50) were electrostatically coated onto the make coat.
  • the ceramic aluminum oxide abrasive grains were made according to U.S. Patent No. 4,881,951.
  • the make coat was then precured for 200 minutes at about 90°C.
  • a conventional cryolite filled resole phenolic resin was applied over the abrasive grains to form a size coat.
  • the size coat was precured for 90 minutes at 88°C. Then the supersize coat was applied over the size coat.
  • Table III sets forth the formulations for preparing the supersize coats, the coating weight of the supersize coats, and curing temperatures for the supersize coats.
  • Formulation I contained 29.57% BPAW, 1.4% EMI, 0.78% "AEROSOL OT", 2.29% iron oxide, 55% KBF4, and 10.92% water.
  • Formulation II contained 35.08% BPAW, 1.68% EMI, 0.78% "AEROSOL OT", 2.17% iron oxide, 52.4% KBF4, and 7.89% water.
  • Formulation III contained 39.83% BPAW, 1.93% EMI, 0.78% "AEROSOL OT", 2.07% iron oxide, 49.75% KBF4, and 5.64% water. After the formulations for preparing the supersize coats were applied, the sheet material was cured for 30 minutes at the temperatures set forth in Table III and then final cured for 24 hours at 99°C. After the curing steps, the sheet material was flexed and rehumidified. After the curing steps, Formulation I contained 76% grinding aid, Formulation II contained 72% grinding aid, and Formulation III contained 68% grinding aid.
  • the sheet material for each example was then converted into 17.8 cm diameter discs with a 2.2 cm diameter center hole.
  • the discs were mounted on a beveled aluminum back up pad and used to grind the face of a 2.5 cm by 18 cm 304 stainless steel workpiece.
  • the discs were driven at 5,500 rpm while the portion of the disc overlaying the beveled edge of the backup pad contacted the workpiece at 4.54 kg pressure.
  • the wear path of the disc was about 140 cm2.
  • Each disc was used to grind a separate workpiece for one minute each for a total duration of 12 minutes.
  • the initial cut was the amount of stainless steel removed in the first minute, and the final cut was the amount of stainless steel removed in the last minute of abrading.
  • Table IV Table III Example no.
  • Formulation Coating weight (g/m2) Cure temperature (°C) 8 III 143 98 9 III 143 121 10 III 184 98 11 III 184 121 12 I 143 98 13 I 143 121 14 I 184 98 15 I 184 121 16 II 163 110 Table IV Example no.
  • Initial cut (g)
  • Final cut (g)
  • Total cut (g) 8 23.4 3.4 110.1 9 24.8 3.4 111.5 10 26.5 3.1 119.9 11 23.8 2.6 113.1 12 26.6 3.2 119.8 13 25.1 3.9 121.5 14 27.1 4.5 136.9 15 25.8 3.6 128.2 16 26.8 3.9 124.8
  • the supersize coat for Comparative Example E contained an epoxy resin coatable from solvent and a cryolite grinding aid and the supersize coats for Examples 17 and 18 contained an epoxy resin coatable from water and a cryolite grinding aid.
  • the article of Comparative Example E was substantially identical to the coated abrasive article of Comparative Example B.
  • the coated abrasive article of Example 17 was substantially identical to the coated abrasive article of Example 5 and the coated abrasive article of Example 18 was substantially identical to the coated abrasive article of Example 6.
  • the coated abrasive articles of these examples were tested in the same manner as were the coated abrasive articles of Examples 1 through 6, except that the workpiece was a 4150 tool steel.
  • the grinding results are set forth in Table V.
  • Table V Example Initial cut (g) Total cut (g) Comparative E 65.6 962 17 58 944 18 63 959
  • the coated abrasive article of Comparative Example F was made and tested in the same manner as was the coated abrasive article of Comparative Example A.
  • the grinding results are set forth in Table VI.
  • the coated abrasive article of Example 19 was made and tested in the same manner as was the coated abrasive article of Comparative Example F except that a different supersize coat was employed.
  • the supersize coat was prepared by charging into a container 2,225 g of a urea-formaldehyde resin ("DURITE Al 8405", Borden Chemical Co.), 2,225 g of epoxy resin (BPAW), 1,555 g of water, 50 g of "AEROSOL OT” dispersing agent, and 5 g of X2-5147 dispersing agent (Dow Chemical Co.). The mixture was stirred until homogeneous; then 225 g of iron oxide pigment and 8,325 g of KBF4 grinding aid were added thereto. The resulting mixture was stirred until homogeneous, and was then applied to the surface of the coated abrasive article at a wet coating weight of 184 g/m2. The grinding results are set forth in Table VI. The supersize coat was cured in the same manner as was the supersize coat in Example 1. Table VI Example Initial cut (g) Final cut (g) Total cut (g) Comparative F 79.7 24.6 581.2 19 86.1 24.6 674.4
  • the coated abrasive article was converted into a 10.2 cm diameter disc and secured to a foam back up pad by means of a pressure-sensitive adhesive.
  • the coated abrasive disc and back up pad assembly were installed on a Schiefer testing machine and the coated abrasive disc was used to abrade a workpiece made of polymethyl methacrylate ("PLEXIGLASS").
  • the load was 4.5 kg. All of the testing was done under conditions of a water flood.
  • the cut was the total amount of polymethyl methacrylate removed during 500 rotations of the coated abrasive disc. Additionally, the cut data represented an average for two coated abrasive discs.
  • a make coat that consisted of 65.7 g of PFAW, 8.08 g of AA, and 26.22 g of water was prepared. The percentage of solids was 45%.
  • the make coat was knife coated onto a waterproof A weight paper at a dry weight of approximately 4 g/m2. The make coat was dried in air for about three minutes. Then, grade P320 silicon carbide was electrostatically projected into the make coat at a weight of approximately 40 g/m2. The resulting construction was cured for five minutes at a temperature of 100°C. Next, a size coat was applied over the abrasive grains at a weight of about 36 g/m2. The size coat was of the same composition as the make coat, except that the percentage of solids was 40%. The resulting construction was cured for about 20 minutes at a temperature of 100°C.
  • the coated abrasive article for Example 21 was made in the same manner as was used in Example 20, except that the weight of the size coat was 44 g/m2.
  • the coated abrasive article for Comparative Example G was a grade 320 "3M 413Q IMPERIAL WETORDRY" A weight paper commercially available from the Minnesota Mining and Manufacturing Company, St. Paul, Minnesota.
  • the abrasive grains were silicon carbide.
  • the coated abrasive article for Comparative Example H was a grade 320 "3M 213Q IMPERIAL WETORDRY" A weight paper commercially available from the Minnesota Mining and Manufacturing Company, St. Paul, Minnesota.
  • the abrasive grains were aluminum oxide.
  • the coated abrasive article for Comparative Example I was a grade 320 coated abrasive article that employed a waterproof A weight paper, and was commercially available from the Komatsubara Company, Japan.
  • the abrasive grains were silicon carbide.
  • Example 21 performed better than the articles of Comparative Examples G, H, and I.
  • the coated abrasive article in Example 22 used a make coat and a size coat that were formed from an epoxy dispersion. All of the coated abrasive articles in this set of examples were tested according to the Schiefer Test, and the test results are set forth in Table VIII. In addition, for this set of examples, the surface finish of the workpiece was measured at the end of the 500 cycles by a Type M4P Perthometer. Ra is the arithmetic mean of the departures of the profile from the mean line in microinches and Rtm is the mean of the maximum peak-to-valley values from each of five consecutive sampling lengths in microinches.
  • a make coat precursor that consisted of PFAW (1,005 g) of AA (1,230 g), silicone surfactant (15 g) and water (3,990 g) was prepared.
  • PFAW had a pH of 7.0, contained 57% solids, and had an epoxy equivalent weight of approximately 205.
  • AA contained about 100% solids.
  • This make coat precursor was roll coated onto a waterproof A weight paper at a wet weight of approximately 4 g/m2. Then, grade 1200 silicon carbide was electrostatically projected into the make coat at a weight of approximately 11 g/m2. The resulting construction was cured for 10 minutes at a temperature of 120°C. Next, a size coat was applied over the abrasive grains at a weight of about 9 g/m2. The size coat was of the same material as the make coat. The resulting construction was cured for between 15 to 20 minutes at a temperature of 120°C.
  • the coated abrasive article of Example 23 was made in the same manner as was that of Example 22, except that the abrasive grain was a grade 600 silicon carbide.
  • the weights of the make coat, abrasive grain, and size coat were about 2, 10 and 17 g/m2, respectively.
  • Example 24 The coated abrasive article in Example 24 was made in the same manner as was that of Example 22, except that the abrasive grain was a grade 400 silicon carbide.
  • the weight of the make coat, abrasive grain, and size coat were about 5, 18 and 15 g/m2, respectively.
  • the coated abrasive article for Comparative Example J was a grade 1200 "IMPERIAL MICROFINE" A weight paper commercially available from Minnesota Mining and Manufacturing Company, St. Paul, Minnesota.
  • the coated abrasive article for Comparative Example K was a grade 1200 waterproofed coated abrasive A weight paper commercially available from the Komatsubara Company, Japan under the trade designation "KOVAX”.
  • the coated abrasive article for Comparative Example L was a grade 1200 coated abrasive that contained a waterproof A weight paper. Comparative Example L was commercially available from the Nikken Company, Japan.
  • the coated abrasive article for Comparative Example M was a grade 600 waterproofed coated abrasive A weight paper commercially available from the Komatsubara Company, Japan under the trade designation "KOVAX”.
  • the coated abrasive article for Comparative Example N was a grade 400 waterproofed coated abrasive A weight paper commercially available from the Komatsubara Company, Japan under the trade designation "KOVAX”.
  • cut and finish need to be balanced.
  • the present invention provides this balance by providing a high cut with a low or fine surface finish.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Polishing Bodies And Polishing Tools (AREA)
EP92311283A 1991-12-11 1992-12-10 Abrasif revêtu contenant une couche en résine époxy appliquée en base aqueuse Expired - Lifetime EP0546831B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US804968 1985-12-02
US80496891A 1991-12-11 1991-12-11

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EP0546831A2 true EP0546831A2 (fr) 1993-06-16
EP0546831A3 EP0546831A3 (en) 1993-08-18
EP0546831B1 EP0546831B1 (fr) 1997-01-22

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EP (1) EP0546831B1 (fr)
JP (1) JPH05261666A (fr)
KR (1) KR930012202A (fr)
AU (2) AU656640B2 (fr)
BR (1) BR9204977A (fr)
DE (1) DE69217019T2 (fr)
MX (1) MX9207000A (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008079934A2 (fr) * 2006-12-21 2008-07-03 Saint-Gobain Abrasives, Inc. Articles abrasifs à faible corrosion et procédés de formation de ceux-ci
CN106368134A (zh) * 2016-09-23 2017-02-01 广东省建筑科学研究院集团股份有限公司 一种特殊路段路面安全改造用反光超薄层及其施工方法

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6843815B1 (en) * 2003-09-04 2005-01-18 3M Innovative Properties Company Coated abrasive articles and method of abrading
US8287611B2 (en) 2005-01-28 2012-10-16 Saint-Gobain Abrasives, Inc. Abrasive articles and methods for making same
US7591865B2 (en) 2005-01-28 2009-09-22 Saint-Gobain Abrasives, Inc. Method of forming structured abrasive article
US8435098B2 (en) 2006-01-27 2013-05-07 Saint-Gobain Abrasives, Inc. Abrasive article with cured backsize layer
CN100478137C (zh) * 2006-03-31 2009-04-15 厦门致力金刚石工具有限公司 一种砂布及其制造方法

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3615303A (en) * 1968-10-18 1971-10-26 Reichhold Albert Chemie Ag Coated abrasive article
FR2307024A1 (fr) * 1975-04-11 1976-11-05 Mobil Oil Compositions de revetement possedant une excellente resistance a la corrosion
DE2657881A1 (de) * 1976-12-21 1978-06-22 Sia Schweizer Schmirgel & Schl Schleifmittel
EP0284064A2 (fr) * 1987-03-27 1988-09-28 Ciba-Geigy Ag Abrasif photodurcissable
EP0486308A2 (fr) * 1990-11-14 1992-05-20 Minnesota Mining And Manufacturing Company Abrasif revêtu avec une couche superficielle en résine epoxy base aqueuse et un additif de polissage

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US4751138A (en) * 1986-08-11 1988-06-14 Minnesota Mining And Manufacturing Company Coated abrasive having radiation curable binder
US4997717A (en) * 1987-03-27 1991-03-05 Ciba-Geigy Corporation Photocurable abrasives
US5061294A (en) * 1989-05-15 1991-10-29 Minnesota Mining And Manufacturing Company Abrasive article with conductive, doped, conjugated, polymer coat and method of making same
US5368618A (en) * 1992-01-22 1994-11-29 Minnesota Mining And Manufacturing Company Method of making a coated abrasive article
US5256170A (en) * 1992-01-22 1993-10-26 Minnesota Mining And Manufacturing Company Coated abrasive article and method of making same

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3615303A (en) * 1968-10-18 1971-10-26 Reichhold Albert Chemie Ag Coated abrasive article
FR2307024A1 (fr) * 1975-04-11 1976-11-05 Mobil Oil Compositions de revetement possedant une excellente resistance a la corrosion
DE2657881A1 (de) * 1976-12-21 1978-06-22 Sia Schweizer Schmirgel & Schl Schleifmittel
EP0284064A2 (fr) * 1987-03-27 1988-09-28 Ciba-Geigy Ag Abrasif photodurcissable
EP0486308A2 (fr) * 1990-11-14 1992-05-20 Minnesota Mining And Manufacturing Company Abrasif revêtu avec une couche superficielle en résine epoxy base aqueuse et un additif de polissage

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008079934A2 (fr) * 2006-12-21 2008-07-03 Saint-Gobain Abrasives, Inc. Articles abrasifs à faible corrosion et procédés de formation de ceux-ci
WO2008079934A3 (fr) * 2006-12-21 2012-02-02 Saint-Gobain Abrasives, Inc. Articles abrasifs à faible corrosion et procédés de formation de ceux-ci
CN106368134A (zh) * 2016-09-23 2017-02-01 广东省建筑科学研究院集团股份有限公司 一种特殊路段路面安全改造用反光超薄层及其施工方法

Also Published As

Publication number Publication date
AU656640B2 (en) 1995-02-09
MX9207000A (es) 1993-06-01
AU2977392A (en) 1993-06-17
DE69217019T2 (de) 1997-07-03
AU669825B2 (en) 1996-06-20
EP0546831A3 (en) 1993-08-18
AU7894294A (en) 1995-01-27
BR9204977A (pt) 1993-06-15
JPH05261666A (ja) 1993-10-12
KR930012202A (ko) 1993-07-20
EP0546831B1 (fr) 1997-01-22
DE69217019D1 (de) 1997-03-06

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