KR20110095309A - Carboxylic acid ester color-stabilized phenolic resin bound abrasive products and methods for making same - Google Patents

Abstract

Phenolic resin binders; Color stabilizers; coloring agent; And a color stable abrasive article comprising abrasive grains. Color stabilizers include one or more carboxylic acid esters. The color stable abrasive article comprises: mixing a resol and a color stabilizer to form a resol composition; Contacting the plurality of abrasive particles with the resol composition; And curing the resol composition to produce a color stable abrasive article. Accordingly, the present invention provides a method for producing an abrasive in which a color stable phenol resin is bound, and an abrasive which is resistant to color change with time and high temperature exposure and maintains the mechanical strength of the phenol resin.

Description

CARBOXYLIC ACID ESTER COLOR-STABILIZED PHENOLIC RESIN BOUND ABRASIVE PRODUCTS AND METHODS FOR MAKING SAME}

Related Application (s)

This application claims the benefit of US Provisional Application No. 61 / 199,472, filed November 17, 2008. The entire teaching of this application is incorporated herein by reference.

The present invention relates to an abrasive in which a carboxylic acid ester color stable phenol resin is bound and a method for producing the same.

The term "phenol resin" represents a wide range of resin products obtained from the reaction product of phenol and aldehyde. Phenol reacts with formaldehyde under both acidic and basic conditions. If the base-catalyst mixture of phenol and formaldehyde contains at least 1 mole of formaldehyde per mole of phenol, a thermoset (single step) resin, or "resole" is produced. Common base compounds used as catalysts for resol resins include hydroxides of alkali metals such as sodium, potassium or lithium. While alkali metal hydroxide-catalyst phenol resins are commercially useful, these resins have the undesirable tendency to blacken as they age, heat or cure. The degree of blackening is known to depend on the curing or use temperature of the resin and the time exposed to such temperature.

Alkali metal hydroxide-catalyst phenolic resins are commonly used as components of a bonding system of abrasive products (eg, abrasive coated, bonded, and steric low density abrasive products). The blackening problem of the resin is particularly pronounced in abrasive paper and three-dimensional low density abrasive products because of the more visual presence of the bonding system. In addition, the degree of blackening increases with temperature and exposure time, so any change in the temperature distribution of the product results in color shift in the product itself. Color shift is particularly noticeable in the case of light colored products, which makes them unacceptable for aesthetic or other reasons.

The abrasive bonding system may also include colorants to identify the manufacturer, product type, use, and the like. Blackening of the resin inhibits the desired coloration, such that the final product has a different color from the added colorant. For example, a resin that usually turns yellow after the curing process will produce a green product when combined with a blue dye or pigment. On the other hand, when the same yellow resin as above is combined with a green dye or pigment, the resin will usually produce only another shade of green.

One known method of imparting color stability to phenol resols involves adding melamine formaldehyde resin to the formulation. While this method achieves color stability, it imparts brittleness, prolongs curing time, and results in mechanical weakness, thereby degrading grinding performance in the final product.

Another proposed method involves adding ammonium based salt to phenol resol. However, this method is not effective enough to stabilize the color of phenolic resin products with specific colorants such as light blue and orange pigments or dyes.

There is a need for an effective phenolic resin color stabilizer that reduces the aforementioned problems without imparting undesirable properties to the final product.

In one aspect, the present invention relates to a color stable abrasive article comprising a phenolic resin binder, a color stabilizer, a colorant and abrasive grains. Color stabilizers include one or more carboxylic acid esters, esters, carboxylic acids, dione groups or acrylic groups.

In another aspect, the invention relates to a method of making a color stable abrasive article, the method comprising: mixing a resol and a color stabilizer to form a resol composition; Contacting the plurality of abrasive particles with the resol composition; And curing the resol composition to produce a color stable abrasive article. The color stabilizer comprises at least one carboxylic acid ester, ester, carboxylic acid, dione group or acrylic group.

In another aspect, the present invention relates to a method of polishing a workpiece, the method comprising applying a color stable abrasive article to the workpiece during the polishing operation to remove a portion of the workpiece. The abrasive includes a binder comprising a phenol resin; Color stabilizers comprising at least one carboxylic acid ester, ester, carboxylic acid, dione group or acrylic group; And abrasive grains.

Accordingly, the present invention provides a method for producing an abrasive in which a color stable phenol resin is bound, and an abrasive which is resistant to color change with time and high temperature exposure and maintains the mechanical strength of the phenol resin.

The foregoing and other objects, features and advantages of the present invention will become apparent from the following more detailed description of the preferred embodiments of the invention as shown in the accompanying drawings, wherein like reference numerals designate the same throughout the different figures. Point to a component. These drawings are not necessarily to scale, emphasis instead being placed upon illustrating embodiments of the invention.
1 is a schematic diagram showing a cross-sectional view of one embodiment of a coated abrasive tool according to the present invention.
2 is a schematic diagram showing a cross-sectional view of another embodiment of a coated abrasive tool according to the present invention.
3 includes photographs of fertilized phenolic resin specimens containing no color stabilizer and cured phenolic resin specimens containing color stabilizer of the present invention.
Figure 4 includes photographs comparing the color change in the control and the color change in one embodiment of the present invention that occurs over time during the curing process.
FIG. 5 is a graph illustrating a color change occurring in the specimens of FIG. 4 over time. FIG.

The teachings of all patents, published applications and references cited herein are hereby incorporated by reference in their entirety. In particular, US Patent Application Serial No. 61 entitled "Acrylate Color-Stabilized Phenolic Bound Abrasive Products and Methods for Making Same" of Wijaya, filed concurrently with the present application; The entirety of / 199,471 is incorporated herein by reference.

The present invention relates to an abrasive article comprising a color stable phenolic resin binder by at least one carboxylic acid ester. The color stable abrasive article further comprises colorants and abrasive grains. As used herein, an abrasive or abrasive resin is considered to have “color stability” if the color after about 2 hours of curing at about 235 ° F. and the color cured about 8 hours at about 235 ° F. is essentially the same.

The term " phenol resin " refers to phenols such as phenol, resorcinol, alkyl-substituted phenols (e.g. cresol), xylenol, p-tert-butylphenol, and p-phenylphenol, and formaldehyde, acetaldehyde and It refers to all resin reaction products with aldehydes such as furfuraldehyde. "Color stable alkali metal hydroxide-catalyst phenol resin" refers to a cured alkali metal hydroxide phenol resin whose color is stabilized by a color stabilizer.

The abrasive is characterized by comprising a phenolic resin binder, at least one carboxylic acid ester color stabilizer, at least one optional colorant, abrasive grains, support members or backings, and a curing agent, unreacted thermoplastics, fillers, grinding aids, and Other additives may be further included.

Structure and manufacturing method of abrasive article

According to one embodiment, the color stable abrasive article comprises a phenolic resin binder, a color stabilizer, and an abrasive material. The color stable abrasive article may be abrasive grinding, molding or abrasive cloth abrasive.

The abrasive foam tool of the present invention may include a substrate, an abrasive material, and one or more phenolic resin binders that secure the abrasive material to the substrate. As used herein, the term "abrasive cloth tool" includes a nonwoven abrasive tool. Abrasive materials, such as abrasive grains, abrasive particles or aggregates thereof, may be present in a single layer (eg, resin-polishing layer) or two layers (eg, make coat and size coat) structure of the abrasive paper tool. Examples of abrasive foam tools that can be manufactured through the methods of the present invention are shown in FIGS. 1 and 2. Referring to FIG. 1, in abrasive polishing tool 10, substrate 12 is treated with an optional backsize coat 16 and an optional presize coat 18. The make coat 20 is stacked on top of the optional pre-sized coat 18, on which abrasive material 14, such as abrasive or abrasive grains, is applied. Optionally, size coat 22 is applied over make coat 20 and abrasive material 14. The upper size coat 22 is any supersize coat 24. Depending on their specific use, the abrasive foam tool 10 may or may not include a backsize coat 16 and / or a freesize coat 18. In addition, depending on their specific uses, the abrasive wrapping tool 10 may or may not include a size coat 22 and / or a supersize coat 24. Shown in FIG. 2 is an example of an abrasive foam tool that may be formed by the methods of the present invention, wherein the abrasive foam tool 30 is a single piece of abrasive material and abrasive (s) (binder-polishing layer 32). Layer and optionally backsize coat 16. Optionally, as shown in FIG. 1, a presized coat 18, a size coat 22, and a supersize coat 24 may be included in the abrasive cloth tool 30. The abrasive foam article may contain a color stable phenolic resin binder in one or more monolayers selected from the group consisting of a binder-abrasive layer, a backsize coat, a presize coat, a make coat, a size coat, and a supersize coat.

As shown in FIG. 1, according to embodiments comprising a size coat and a supersize coat, the abrasive material may be applied separately by gravity, electrostatic deposition or air stream or as a slurry together with the polyurethane adhesive composition. Can be. The make coat 20 serves to adhere the abrasive material to the surface of the substrate, and may be formed by impregnating the support substrate with an abrasive free phenolic resin binder.

According to the embodiment of FIG. 2, the support substrate is impregnated with a resin / abrasive slurry containing an abrasive material and a resin composition (containing phenolic resin binder and color stabilizer) to form a binder / abrasive layer 32.

According to one embodiment, a method of making a color stable abrasive article comprises: mixing a resol, and a color stabilizer comprising at least one carboxylic acid ester to form a resol composition; Contacting the plurality of abrasive particles with the resol composition; And curing the resol composition to produce a color stable abrasive article. The color stable abrasive article formed by this method includes, for example, a molded abrasive and an abrasive grindstone abrasive in addition to the abrasive cloth abrasive described above.

With regard to molded abrasive, the (polishing) article is formed by any of the techniques known in the art, wherein the abrasive structure is molded before the curing step. Such techniques include, for example, embossing techniques. According to one embodiment, for example, a phenol resin binder; At least one compound selected from the group consisting of carboxylic esters, esters, carboxylic acids, dione group-containing compounds, acrylic group-containing compounds, and combinations thereof; Any colorant; And a mixture comprising the abrasive can be contacted with the substrate and an abrasive tool with the mixture adhered to one surface of the substrate. The abrasive structure is thus shaped along the shape of the abrasive tool inner surface.

The abrasive grinding article includes a phenol resin binder; At least one compound selected from the group consisting of carboxylic esters, esters, carboxylic acids, dione group-containing compounds, acrylic group-containing compounds, and combinations thereof; Any colorant; And agglomerates comprising abrasive grains. The agglomerates are then formed using any of the techniques known in the art for abrasive grinding. Techniques suitable for producing abrasive grinds are described, for example, in US Pat. No. 5,738,696 to Wu; Wu, et al . US Pat. No. 5,738,697; Bright, et al . US Pat. No. 6,679,758; And US Patent Publication No. 2003/0192258 A1 to Simon, the entire contents of each of which are incorporated herein by reference.

A color stable abrasive article is applied to the workpiece surface during the polishing operation to remove a portion of the workpiece surface to polish the workpiece surface.

Phenolic Resin Binder

Typical phenolic resins used in the present invention are resols, where resol is used in the presence of an alkali metal hydroxide catalyst for phenol and formaldehyde, with a molar ratio of phenol to formaldehyde of about 1: 1 to about 1: 3 and phenol: alkali metal hydroxide. Is produced by reacting a molar ratio of from about 1: 1 to about 100: 1. The color of this resol, or base-catalyst phenol resin, is stabilized by the addition of one or more carboxylic acid esters. An example of an aqueous single-stage liquid phenolic resin that can be used as a binder is Durez Varcum Resin No. manufactured by Durez. There is 94908.

Color stabilizer

Color stabilizers used in the present invention include carboxylic acid esters, esters, carboxylic acids, dione group-containing compounds, acrylic group-containing compounds, and combinations thereof. For example, suitable compounds include methyl lactate, ethyl lactate, n-propyl lactate, butyl lactate, 2-ethylhexyl lactate, heptanoic acid, lactic acid, ethyl acetoacetate, 2,2,5-trimethyl- 1-3-dioxane-4-6-dione, and 2- (dimethylamino) ethylmethacrylate.

In certain embodiments, the color stabilizer is present in an amount from about 1% to about 40% by weight of the phenol resin. In other embodiments, the color stabilizer is present in an amount from about 4% to about 10% by weight of the phenol resin.

It has been found that ethyl lactate is particularly effective. For example, one embodiment of the present invention includes:

Ingredient                        % ---__

Durez 94-908 PF Resin 53.89

Ethyl lactate 2.72

Tamol 165A 0.8

Nalco 2341 0.29

Blue Dye / Pigment 4.81

Syn. Cryolite 37.3

Cab-o-sil 0.19

Heptanoic acid, lactic acid, ethyl acetoacetate, 2,2,5-trimethyl-1-3-dioxane-4-6-dione and 2- (dimethylamino) ethylmethacrylate are 5% or 10% of the total weight of the resin. It has proven to be an effective color stabilizer when added in small amounts of%.

coloring agent

The abrasive may comprise colorants, for example dyes or pigments. In general, some of the colorants can be seen through the cured resin. According to some embodiments, a portion of the colorant is contained in the cured resin, in any support substrate and / or in the coating between any support substrate and the cured resin. According to certain embodiments, the colorant may comprise an organic polycyclic dye, an organic monoazo dye, an organic diazo dye, an organometallic complex, an inorganic pigment (metal-oxide or complex). The dye may be perinone, anthraquinone, azo dye complex and thioindigoid.

Fluorescent colorants are dyes or pigments containing fluorescent organic molecules. A detailed description of fluorescent colorants can be found in Zollinger, H., "Color Chemistry: Synthesis, Properties, and Applications of Organic Dyes and Pigments", 2 ^nd Ed., VCH, New York, 1991, the full teaching of which Incorporated herein by reference. As used herein, fluorescent colorants include, for example, xanthenes, thioxanthenes, fluorenes (eg, fluorescein, rhodamine, eosin, phloxines, uranines, succinates). Succineins, sacchareins, rosamines, and rhodols), naphthylamines, naphthylimides, naphtholactam, azalactone, azalactone, methine, oxazine , Thiazine, benzopyran, coumarin, aminoketone, anthraquinone, isoviolanthrone, anthrapyridone, pyranine, pyrazolone, benzothiagen, perylene, or thioindigoide. More preferably, the fluorescent colorant is a group consisting of xanthene, thioxanthene, benzopyran, coumarin, aminoketone, anthraquinone, isoviolatron, anthrapyridone, pyranine, pyrazolone, benzothiagen, thioindigoide and fluorene Is selected. Most preferably, the fluorescent colorant is thioxanthene.

Those skilled in the art will appreciate that for many commercially available colorants, the specific chemical structure of individual derivatives (eg, thioxanthene derivatives) within a class may not be publicly available. Thus, "Colour Index International", 4 ^th Ed. As defined in the American Association of Textile Chemists and Colorists, Research Triangle Park, NC, 2002, certain fluorescent colorants are commonly designated by color index (CI) names. The color index is also available online at www.colour-index.org. Full teachings on color index are incorporated herein by reference.

Examples of preferred fluorescent colorants include C.I. Solvent Orange 63 (Hostasol Red GG, Hoechst AG, Frankfurt, Germany), C.I. Solvent Yellow 98 (Hostasol Yellow 3G, Hoechst AG, Frankfurt, Germany), and C.I. Solvent Orange 118 (FL Orange SFR, Keystone Aniline Corporation, Chicago, Illinois).

The amount of colorant that can be used depends on the details of the intended use, the properties of the colorant, other components in the composition, and the like. Those skilled in the art will be familiar with how to determine these details to determine the amount of colorant for a particular use. Usually, the amount of colorant is in the weight fraction of the total composition, from about 0.01 to about 2%, more preferably from about 0.05 to about 0.5%, most preferably about 0.2%.

In certain embodiments, the colorant is a red, orange, yellow, green, blue, indigo or purple colorant. In certain embodiments, the colorant is a fluorescent colorant such as, for example, fluorescent red, blaze orange, fluorescent yellow, fluorescent green, and the like.

Examples of suitable colorants include Elcoment Orange GS (Blaze), Elcoment Green Nort Liq., And especially Elcoment Blue RS available from Greenville Colorants, SC Greenville; And Akrosperse E5137 available from Akrochem Corp. of Akron, Ohio.

Colorants can be used to identify abrasives, for example for commercial branding, to indicate uses (such as wet, dry, wood, metal, etc.), or to identify grit sizes.

Abrasive material

The abrasive grains include, but are not limited to, silica, (melted or sintered) alumina, zirconia, zirconia / alumina oxide, silicon carbide, garnet, diamond, cubic boron nitride (CBN), silicon nitride, ceria, titanium dioxide Any one or combination of abrasive grains containing titanium diboride, boron carbide, tin oxide, tungsten carbide, titanium carbide, iron oxide, chromia, flint, and emery It may include. For example, abrasive grains include silica, alumina, zirconia, silicon carbide, silicon nitride, boron nitride, garnet, diamond, co-fused alumina zirconia, ceria, titanium diboride, boron carbide, flint, emery, alumina nitride, and their It may be selected from the group consisting of a mixture. In some examples, high density abrasive grains consisting predominantly of alpha-alumina and / or gamma alumina are available.

The abrasive grains may also comprise abrasive aggregates, also known as aggregated abrasive grains. The abrasive aggregates comprise abrasive particles adhered together through the particle binder material. Abrasive particles present in the abrasive aggregates are abrasives known to be used in abrasive tools, such as silica, (fused or sintered) alumina, zirconia, zirconia / alumina oxide, silicon carbide, garnet, diamond, cubic boron nitride ( CBN), silicon nitride, ceria, titanium dioxide, titanium diboride, boron carbide, tin oxide, tungsten carbide, titanium carbide, iron oxide, chromia, flint, emery, and combinations thereof. . The abrasive particles can have any size or shape. The abrasive aggregates may be glued together through particle binder materials (eg, metal, organic or glassy materials, or combinations of these materials). For abrasive aggregates suitable for use in the present invention Knapp, et al . Further described in US Pat. No. 6,797,023, which is incorporated herein by reference in its entirety.

The abrasive grains can have one or more specific shapes. Examples of such specific shapes include rods, triangles, pyramids, cones, solid spheres, hollow spheres, and the like. Alternatively, the abrasive grains may have an irregular shape.

Usually, the average particle diameter of an abrasive grain is 2000 microns or less, for example, about 1500 microns or less. In another example, the size of the abrasive grain is about 750 microns or less, for example about 350 microns or less. In some embodiments, the size of the abrasive grain is at least about 0.1 microns, for example, from about 0.1 microns to about 1500 microns, and more generally from about 0.1 microns to about 200 microns, or from about 1 micron to about 100 microns. . The size of the abrasive grain is usually specified by the longest dimension of the abrasive grain. In general, there is a range distribution of abrasive size. In some examples, the grain size distribution is tightly controlled.

Support member / base material

The abrasive article may comprise a support member or a substrate. The substrate can be flexible or rigid. The substrate can be made of many different materials, including those conventionally used as substrates in abrasive paper manufacture. Suitable substrates include polymeric films (eg prime films), such as polyolefin films ( eg polypropylene including biaxially oriented polypropylene), polyester films ( eg polyethylene terephthalate), polyamide films, Or cellulose ester films; Metal foil; Mesh (fabric in mesh); Foams ( eg , natural sponge materials or polyurethane foams); Cloth ( eg , woven, non-woven, wool, stitch-bond, quilt, or fibers (such as polyester, nylon, silk, cotton, polycotton or rayon) or yarn); paper; Vulcanized paper; Vulcanized rubber; Vulcanized fibers; Nonwoven materials; Substrates treated with these; Or any combination thereof.

The substrate may include one or more of a saturation material, a presized layer or a backsized layer. Usually the purpose of these layers is to seal the substrate or to protect the twisted yarns or fibers in the substrate. If the substrate is a woven material, at least one of these three layers is usually used. By adding a presize layer or a backsize layer, the front or back side of the substrate can be further "smooth". Any other layer known in the art (eg, a tie layer; Stoetzel, et. , Which is incorporated herein by reference in its entirety). al . US Pat. No. 5,700,302) may be used.

In some embodiments, a very smooth surface may be desirable as the abrasive article is intended to be used as a precision grinding material. Examples of such smooth surface substrates include finely calendered paper, plastic films or fabrics with smooth surface coatings.

The substrate may have antistatic properties. The addition of an antistatic material tends to result in less static buildup in the abrasive article when sanding the wood or similar material with the abrasive article. Further details regarding antistatic substrates and substrate treatments are described, for example, in Buchanan,et alUS Patent No. 5,108,463; Buchanan,et alUS Patent No. 5,137,542; US Pat. No. 5,328,716 to Buchanan; Buchanan,et alUS Pat. No. 5,560,753, which is hereby incorporated by reference in its entirety.

The substrate is for example Stout, et or fibrous reinforced thermoplastics, as described in US Pat. No. 5,417,726 to al ., for example Benedict, et. and an annular spiceless belt as described in US Pat. No. 5,573,619 to al . (incorporated herein by reference in its entirety). Likewise, the description is given, for example, by Chesley, et. Al . US Pat. No. 5,505,747, which may include a polymeric substrate with protruding hooking stems. Similarly, a description may be made of, for example, Follett, et. , The entire contents of which are incorporated herein by reference. loop fabrics as described in US Pat. No. 5,565,011 to al .

Other Ingredients

The abrasive article of the present invention may also include various other components, such as curing additives, unreacted thermoplastics, fillers, grinding aids, and other additives.

According to some embodiments, the abrasive article includes a curing additive, such as a photoinitiator, that generates free radicals when exposed to radiation such as UV radiation. Free-radical generators include organic peroxides, azo compounds, quinones, benzophenones, nitroso compounds, acrylic halides, hydrozones, mercapto compounds, pyryllium compounds, triacrylimidazoles, bisimidazoles, chloroalkyltriazines , Benzoin ether, benzyl ketal, thioxanthone, acetophenone, derivatives of these compounds may be included. Photoinitiators the most commonly used of these are benzyl ketals, such as 2,2-dimethoxy-2-phenyl acetophenone (available as IRGACURE ^® 651 brand from Ciba Specialty Chemicals, Inc.) and acetophenone derivatives such as 2,2- Diethoxyacetophenone ("DEAP", available from First Chemical Corporation), 2-hydroxy-2-methyl-1-phenyl-propan-1-one ("HMPP", trademarked DAROCUR ^® 1173 from Ciba Specialty Chemicals purchase available), 2-benzyl -2-N, N- dimethylamino-1- (4-morpholinophenyl) -1-butanone (available as IRGACURE ^® 369 brand purchased from Ciba Specialty Chemicals Corp.); And 2-methyl-1- (4- (methylthio) phenyl) -2-morpholinopropan-1-one (available under the IRGACURE ^® 907 trademark from Ciba Specialty Chemicals).

The abrasive article may include, for example, non-reactive thermoplastics such as polypropylene glycol, polyethylene glycol, and polyoxypropylene-polyoxyethene block copolymers.

Fillers include organic fillers, inorganic fillers, and nano fillers. Examples of suitable fillers include metal carbonates such as calcium carbonate, sodium carbonate; Silica such as quartz, glass beads, glass bubbles; Silicates such as talc, clays, calcium metasilicates; Metal sulfates such as barium sulfate, calcium sulfate, aluminum sulfate; Metal oxides such as calcium oxide, aluminum oxide; Aluminum trihydrate, and combinations thereof, including but not limited to.

The abrasive article may include a grinding aid to increase the grinding efficiency and cutting rate. Useful grinding aids are inorganic, such as halogenated salts such as sodium cryolite and potassium tetrafluoroborate; Or organic, such as chlorinated wax (eg, polyvinyl chloride). According to one particular embodiment, the abrasive article comprises cryolite and potassium tetrafluoroborate having a particle size in the range of about 1 micron to about 80 microns, most typically in the range of about 5 microns to about 30 microns. Include. The concentration of the grinding aid in the make coat is usually about 50% by weight or less, based on the weight of the make coat including the abrasive, for example, often from about 0.1% to 50% by weight, most commonly About 10% to 30% by weight.

Examples of additional additives include coupling agents such as A-174 and A-1100, titanates, and zircoaluminates available from Osi Specialties, Inc .; Antistatic agents such as graphite, carbon black and the like; Suspending agents such as fumed silica (eg, Cab-O-Sil M5, Aerosil 200); Pore blockers, such as zinc stearate and calcium stearic acid; Lubricants such as waxes, PTFE powders, polyethylene glycols, polypropylene glycols, and polysiloxanes; Wetting agents; Pigments; Dispersing agent; And antifoaming agents.

excuse

Example  One

The present invention will be described in more detail with reference to the following examples without intention of limiting the invention.

As color stabilizers of the following compounds: heptanoic acid, lactic acid, ethyl acetoacetate, 2,2,5-trimethyl-1-3-dioxane-4-6-dione, and 2- (dimethylamino) ethylmethacrylate The performance was tested. Preparations containing pure phenolic resin and color stabilizer (4% to 10% per weight of resin) were prepared and cured at 180 ° C. for 12 hours; Heptanoic acid was cured at 250 ° F. for 6 hours. Cured samples are shown in FIG. 3.

Example  2

Ethyl lactate as a color stabilizer in phenolic resin size coat formulations was tested and compared to a control formulation without ethyl lactate. The formulations are described below:

Control size formulation (" Color stability  Without " Considered )

ingredient %

Durez 94-908 PF resin 55.39

Tamol 165A 0.81

Nalco 2341 0.32

Blue Dye / Pigment 4.94

Synthetic Cryolite 38.34

Cab-O-Sil 0.20

Color stability  Size Formulation (Ethyl Lactate  Containing)

ingredient %

Durez 94-908 PF Resin 53.89

Ethyl lactate 2.72

Tamol 165A 0.8

Nalco 2341 0.29

Blue Dye / Pigment 4.81

Synthetic Cryolite 37.3

Cab-o-sil 0.19

All of the above formulations were applied to previously prepared abrasive paper samples. These samples include substrates, wherein on the substrates, the mate coats and abrasive grains were coated and cured to a moderate degree prior to application of the usual size coats during normal manufacturing procedures.

After the two size coats were applied to prefabricated abrasive paper to prepare a standard size cure, five samples were taken from each and placed in an oven at 235 ° F., followed by a “post cure” process. To mimic one of the samples was taken out of the oven after 2, 4, 6, 8 and 24 hour residence times. The visual comparison result for the color shift is shown in FIG. 4.

In addition to the above qualitative comparison for color shift, a qualitative comparison was further performed using HunterLab's MiniScan XE Plus colorimeter and the results are provided in FIG. 5.

Figure 5 shows Delta E, the degree of reduction of overall color shift with ethyl lactate. Normal post-curing step conditions were 4 hours to 8 hours. In this case, the delta E observable for the color unstable size increased from 11.14 to 17.18 during this time, showing a difference of 6.04. When ethyl lactate was used at 5% by weight of the resin, delta E increased only from 6.12 to 8.31, showing a difference of 2.19, indicating a significant reduction in color shift.

Equal Example

While the invention has been shown and described with reference to preferred embodiments, it will be apparent to those skilled in the art that various changes may be made in form and detail in these embodiments without departing from the scope of the invention including the appended claims. I will understand that.

Claims (15)

a) a binder comprising a phenolic resin;
b) color stabilizers comprising at least one carboxylic acid ester; And
c) color stable abrasive articles comprising abrasive grains. The color stable abrasive article of claim 1, wherein the color stabilizer comprises a compound selected from the group consisting of carboxylic acid esters, esters, carboxylic acids, dione group-containing compounds, acrylic group-containing compounds, and combinations thereof. The color stable abrasive article of claim 2, wherein the color stabilizer comprises lactate. The color stabilizer according to claim 2, wherein the color stabilizer is heptanoic acid, lactic acid, ethyl acetoacetate, 2,2,5-trimethyl-1,3-dioxane-4-6-dione, ethyl lactate, and 2- (dimethylamino) Color stable abrasive article comprising at least one compound selected from the group consisting of ethyl methacrylate. The color stable abrasive article of claim 1, wherein the phenolic resin is resol. The color stable abrasive article of claim 1, wherein the color stabilizer is present in an amount from about 1% to about 40% by weight of the phenol resin. The color stable abrasive article of claim 6, wherein the color stabilizer is present in an amount from about 4% to about 10% by weight of the phenolic resin. The color stable abrasive article of claim 1, further comprising a support member. The color stable abrasive article of claim 1, further comprising a common agent. 10. The color stable abrasive article of Claim 9, wherein the coagent is a glycol. The color stable abrasive article of claim 1, further comprising a curing additive comprising at least one additive selected from the group consisting of peroxides and UV photoinitiators. The color stability of claim 1, wherein there is no noticeable visual color change as a result of comparing the abrasive article cured at about 235 ° F. for about 2 hours and the same abrasive article cured at about 235 ° F. for about 8 hours. Abrasive products. The color of claim 1, wherein the phenolic resin binder and color stabilizer are present in at least one layer selected from the group consisting of a binder-polishing layer, a backsize coat, a freesize coat, a make coat, a size coat, and a supersize coat. Stability abrasive products. a) mixing a resol, and a color stabilizer comprising at least one carboxylic acid ester to form a resol composition;
b) contacting the plurality of abrasive particles with the resol composition; And
c) curing the resol composition to produce a color stable abrasive article. A method of polishing a workpiece, comprising applying a color stable abrasive article to the workpiece surface during the polishing operation to remove a portion of the workpiece surface.
a) a binder comprising a phenolic resin;
b) a color stabilizer comprising a compound selected from the group consisting of carboxylic esters, esters, carboxylic acids, dione group-containing compounds, acrylic group-containing compounds, and combinations thereof; And
c) A workpiece grinding method comprising abrasives.

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