WO2018217523A1

WO2018217523A1 - Cleaning article with decorative particles

Info

Publication number: WO2018217523A1
Application number: PCT/US2018/033083
Authority: WO
Inventors: Myhanh T. Truong; Shridhar B. Shinde; Gregory G. MEHSIKOMER
Original assignee: 3M Innovative Properties Company
Priority date: 2017-05-24
Filing date: 2018-05-17
Publication date: 2018-11-29
Also published as: KR20200011419A; US20200180112A1; BR112019024791A2; CN110662472A; CA3064720A1; EP3629871A1; MX2019013572A; TW201900780A

Abstract

The present invention is a cleaning article including a substrate, a base coating on at least a surface of the substrate, and a surface coating disposed on the base coating. The surface coating includes water, a binder, a cross-linker, a thickener, and decorative particles. The decorative particles constitute between about 30 to about 300 grams per square meter wet basis weight of the cleaning article. At least about 50% of the decorative particles remains on the cleaning article after use.

Description

CLEANING ARTICLE WITH DECORATIVE PARTICLES

Field

The present disclosure relates to a cleaning article. In particular, the present disclosure relates to a cleaning article having decorative particles.

Background

Cleaning articles, such as scouring materials, are produced in many forms. These cleaning articles may be formed from any known material used for cleaning or scouring and may include abrasive particles and other additives to increase their cleaning power. Examples of useful cleaning articles are formed from natural or synthetic sponges and nonwoven articles.

Nonwoven abrasive articles generally have a nonwoven web (e.g., a lofty open fibrous nonwoven web), abrasive particles, and a binder material (commonly termed a "binder") that bonds the fibers within the nonwoven web to each other and secures the abrasive particles to the nonwoven web. Examples of nonwoven abrasive articles include nonwoven abrasive hand pads and surface conditioning abrasive discs and belts such as those marketed by 3M Company of Saint Paul, Minnesota under the trade designation SCOTCH-BRITE.

Summary

In one embodiment, the present invention is a cleaning article including a substrate, a base coating on at least a surface of the substrate, and a surface coating disposed on the base coating. The surface coating includes water, a binder, a cross-linker, a thickener, and decorative particles. The decorative particles constitute between about 30 to about 300 grams per square meter wet basis weight of the cleaning article. At least about 50% of the decorative particles remains on the cleaning article after use.

Brief Description of the Drawings

FIG. 1 A is a photograph of a cleaning article of the present invention.

FIG. IB is a perspective view of a cleaning article of the present invention. FIG. 2A is a magnified view of a cleaning article of the present invention with decorative glitter particles.

FIG. 2B is a microscopic photograph of a first embodiment of decorative particles on the cleaning article of the present invention.

FIG. 2C is a microscopic photograph of a second embodiment of decorative particles on the cleaning article of the present invention.

FIG. 3 is a magnified view of a cleaning article of the present invention with decorative plastic particles.

It should be understood that numerous other modifications and embodiments can be derived by those skilled in the art, which fall within the scope and spirit of the principles of the disclosure. The figures may not be drawn to scale.

Detailed Description

FIG. 1 A shows a photograph and FIG. IB shows a perspective view of the cleaning article 10 of the present invention, which may be a scouring pad, having a durable surface coating that includes decorative particles. The surface coating of the cleaning article minimizes the amount of decorative particles that flake off during the coating process and during use without adversely affecting the cleaning efficiency of the cleaning article.

The cleaning article 10 includes a substrate 12 with a base coating 14 and a surface coating 14. The base coating 14 is embedded within the substrate 12. The surface coating 16 is then coated over the substrate 12 and the base coating 14. In one embodiment, the substrate 12 includes a top surface 18 and a bottom surface 20 opposite the top surface 18. In one embodiment, the top surface 18 and bottom surface 20 are generally planar. While FIG. 1 depicts the cleaning article 10 as being generally rectangular, it is understood that any number of shapes and sizes of the substrate may be used for the cleaning article 10. For example, the cleaning article 10 may be circular, triangular, or square surfaces may be provided.

Generally, either or both the top surface 18 and bottom surface 20 are working surfaces that are intended to make contact with the surface to be cleaned. In one embodiment, more than two working surfaces may be included. For example, if the substrate 12 has a cube shape, it may be that all six sides of the cube are working surfaces intended to contact the surface to be cleaned. In addition, although in FIG. 1, the surfaces are shown as including a texture but as a whole are generally planar, it is not essential that the working surface be planar. The working surface may be textured, patterned, angled, concavely or convexly curved. The working surface may include raised regions and recessed regions.

In one embodiment, the cleaning article 10 has a thickness of between about 2 and about 50 millimeters, particularly between about 15 and about 35 millimeters, and more particularly between about 10 and about 18 millimeters. In one embodiment, the cleaning article has a basis weight of between about 50 and about 1500 grams/meter^2, particularly between about 300 and about 1200 grams/meter², and more particularly between about 500 and about 900 grams/meter².

The substrate 12 may be any known material in the art used for wiping, cleaning, or scouring. Useful substrates include, but are not limited to: natural or synthetic sponges, pads formed of metal fibers such as steel wool pads or pads formed of narrow aluminum, bronze or plastic fibers or ribbons, paper, fabrics, knitted fabric, including three dimensional knitted spacers, woven fabric, and nonwoven fabric, polyurethane foams, and reticulated foams.

Nonwoven articles are particularly suitable as a substrate for the cleaning article 10. A nonwoven article is a web of fibers bonded to one another. One exemplary nonwoven web that may be suitable as the substrate 12 of the cleaning article 10 is the open, lofty, three-dimensional air-laid nonwoven substrate described in U.S. Pat.

2,958,593 to Hoover et al, the disclosure of which is included herein. This nonwoven web is formed by randomly disposed fibers. One commercial product comprising such a nonwoven web is that sold under the trade designation "Scotch-Brite" available from 3M Company, St. Paul, Minn.

Typically, the nonwoven fiber web includes an entangled web of fibers 22. The fibers may include continuous fiber, staple fiber, or a combination thereof. For example, the fiber web 22 may include staple fibers having a length of between about 20 to about 150 millimeters, particularly between about 40 and about 70 millimeters, and more particularly between about 40 and about 56 millimeters, although shorter and longer fibers (e.g., continuous filaments) may also be useful. The fibers may have a fineness or linear density of at least about 1.7 decitex (dtex, i.e., grams/10000 meters), at least about 6 dtex, or at least about 17 dtex, and less than about 560 dtex, less than about 280 dtex, or less than about 120 dtex, although fibers having lesser and/or greater linear densities may also be useful. If a spunbond nonwoven is used, the filaments may be of substantially larger diameter, for example, up to about 2 mm or more in diameter. It is contemplated that fibers of mixed denier can be used in the manufacture of a nonwoven web in order to obtain a desired surface finish. The use of larger fibers is also contemplated, and those skilled in the art will understand that the invention is not limited by the nature of the fibers employed or by their respective lengths, linear densities and the like.

The fiber web 22 may be made, for example, by conventional air laid, carded, stitch bonded, spun bonded, wet laid, and/or melt blown procedures. Air laid fiber webs may be prepared using equipment such as, for example, that available under the trade designation RANDO WEBBER from Rando Machine Company of Macedon, New York.

Nonwoven fiber webs are typically selected to be compatible with adhering binders and abrasive particles, if included, while also being compatible with other components of the cleaning article, and typically can withstand processing conditions

(e.g., temperatures) such as those employed during application and curing of the curable binder precursor. The fibers may be chosen to affect properties of the cleaning article such as, for example: flexibility, elasticity, durability or longevity, abrasiveness, and finishing properties. Examples of fibers that may be suitable include, but are not limited to: natural fibers, synthetic fibers, and mixtures of natural and/or synthetic fibers.

Examples of synthetic fibers include, but are not limited to: those made from polyester (e.g., polyethylene terephthalate), nylon (e.g., hexamethylene adipamide,

polycaprolactam), polypropylene, acrylonitrile (i.e., acrylic), rayon, cellulose acetate, polyvinylidene chloride-vinyl chloride copolymers, and vinyl chloride-acrylonitrile copolymers. Examples of suitable natural fibers include, but are not limited to: cotton, wool, jute, and hemp. The fiber may be of virgin material or of recycled or waste material, for example, reclaimed from garment cuttings, carpet manufacturing, fiber manufacturing, or textile processing. The fiber may be homogenous or a composite such as a bicomponent fiber (e.g., a co-spun sheath-core fiber). The fibers may be tensilized and crimped, but may also be continuous filaments such as those formed by an extrusion process. Combinations of fibers may also be used. In those nonwoven cleaning articles including a lofty open nonwoven fiber web (e.g., hand pads, and surface conditioning discs and belts, flap brushes, or nonwoven abrasive webs used to make unitized or convolute abrasive wheels) many interstices between adjacent fibers are substantially unfilled by the binder and optically abrasive particles, resulting in a composite structure of extremely low density having a network on many relatively large intercommunicated voids. The resulting lightweight, lofty, extremely open fibrous construction is essentially non-clogging and non-filling in nature, particularly when used in conjunction with liquids such as water and oils. These structures also can be readily cleaned upon simple flushing with a cleansing liquid, dried, and left for substantial periods of time, and then reused. Towards these ends, the voids in these nonwoven abrasive articles may make up at least about 75 percent, and preferably more, of the total space occupied by the composite structure.

To chemically bind the fibers together, the web 22 may be reinforced, for example, by the application of the base coating 14, which typically is a resin to bond the fibers at their mutual contact points to form a three-dimensionally integrated structure as described in Hoover et al. In some constructions, an additional second base coating is applied over the first base coating to further reinforce the web. The selection and amount of binder actually applied can depend on any of a variety of factors including, for example: the fiber weight in the nonwoven web, the fiber density, the fiber type, as well as the contemplated end use for the finished article. Exemplary methods of applying the base coating include :roll coating, spray coating, dry powder coating, suspended powder coating, powder dropping, liquid dip coating, fluidized bed powder coating, electrostatic powder coating, critical gas dilution liquid resin coating, or other commonly used coating processes.

Other known means of forming a three-dimensionally integrated structure from the nonwoven fibers are within the scope of the present invention. As an alternative or in addition to the base coating applied to the fibers to form the nonwoven, the fibers may be melt-bonded together at a portion of points where they contact one another to form a three-dimensionally integrated structure, as described in U.S. Pat. No. 5,685,935 to Heyer et al.

The base coating 14 generally includes water, binder, anti-foaming agent, additive, and pigment. In one embodiment, the base coating 14 includes between about 10 and about 50 wt% water, particularly between about 15 and about 45 wt% water, and more particularly between about 20 and about 40 wt% water. In one embodiment, the base coating 14 includes between about 40 and about 70 wt% binder, particularly between about 40 and about 60 wt% binder, and more particularly between about 35 and about 45 wt% binder. In one embodiment, the base coating 14 includes between about 0.01 and about 1 wt% anti-foaming agent, particularly between about 0.01 and about 0.75 wt% anti-foaming agent, and more particularly between about 0.05 and about 0.5 wt% anti- foaming agent. In one embodiment, the base coating 14 includes between about 2 and about 10 wt% additive, particularly between about 5 and about 7 wt% additive, and more particularly between about 7 and about 7 wt% additive. The selection of additive will depend on the binder selection. In one embodiment, the base coating 14 includes between about 0.2 and about 2 wt% pigment, particularly between about 0.5 and about 1.5 wt% pigment, and more particularly between about 0.6 and about 1 wt% pigment.

The base coating 14 may be applied to the substrate 12 by roll coating, spray coating, immersion coating, or other known coating techniques. The surface coating 16 may then be applied over the base coating 14 by roll coating, spray coating, immersion coating, or other known coating techniques.

The selection and amount of the base coating 14 actually applied to the substrate 12 can depend on any of a variety of factors including, for example, the substrate type. If the substrate is a nonwoven, factors to consider include the fiber weight in the nonwoven web, the fiber density, the fiber type, as well as the contemplated end use for the finished article. In one embodiment, the coating weight of the base coating 14 may range from about 50 to about 300 gsm(dry), and particularly from about 100 to about 200 gsm(dry). In one embodiment, the coating weight of the surface coating 16 may range from about 50 to about 400 gsm(wet), and particularly from about 150 to about 250 gsm(wet).

The surface coating 16 generally includes water, a binder, a crosslinker, a thickener and decorative particles 24. In one embodiment, the surface coating 16 includes between about 5 to about 25% by weight water, particularly between about 10 and about 25% by weight water and more particularly between about 15 and about 25% by weight water.

The binder incorporated in the surface coating 16 may be the same binder or different from the binder incorporated in the base coating 14. The binder is any substance that will cohere to the substrate. Following curing, the binder may be water soluble or water insoluble. In one embodiment, the binder of the surface coating 16 is a resin.

Suitable resins include, but are not limited to: phenolic resins, polyurethane resins, polyureas, styrene-butadiene rubbers, nitrile rubbers, epoxies, acrylics, and polyisoprene. The binder may be water soluble. Examples of water soluble binders include water-soluble binders include surfactants, polyethylene glycol, polyvinylpyrrolidones, polylactic acid

(PLA), polyvinylpyrrolidone/vinyl acetate copolymers, polyvinyl alcohols, carboxymethyl celluloses, hydroxypropyl cellulose starches, polyethylene oxides, polyacrylamides, polyacrylic acids, cellulose ether polymers, poly ethyl oxazolines, esters of polyethylene oxide, esters of polyethylene oxide and polypropylene oxide copolymers, urethanes of polyethylene oxide, and urethanes of polyethylene oxide and polypropylene oxide copolymers.

Examples of suitable curable binders include resole phenolic resins, novolac phenolic resins, epoxy resins, polymerizable acrylic monomers oligomers and polymers, alkyd resins, cyanate resins, aminoplast resins, urea-formaldehyde resins, urethane resins (one-part and two-part), and combinations thereof. Depending on the curable binder precursor system selected, an appropriate curative (e.g., a crosslinker, catalyst, or initiator) may also be present. The selection and amounts of suitable such curatives are well known in the abrasives art. An example of a commercially available polyurethane resin includes, but is not limited to, Alberdingk® U9380, available from AlberdingK Boley Inc. located in Greensboro, NC.

Curable binder compositions may contain various additives. For example, conventional resin filler(s) (e.g., calcium carbonate or fine fibers), lubricant(s) (e.g., alkali metal salts of stearic acid and light petroleum oils), grinding aid(s) (e.g., potassium fluorob orate), wetting agent(s) or surfactant(s) (e.g., sodium lauryl sulfate), defoamer(s), pigment(s), dye(s), biocide(s), coupling agent(s) (e.g., organosilanes), plasticizer(s) (e.g., polyalkylene polyols or phthalate esters), thickeners, and combinations thereof. Typically, the curable binder precursor will include at least one solvent (e.g., isopropyl alcohol, methyl ethyl ketone, water) to facilitate coating of the curable binder precursor on the nonwoven fiber web, although this is not a requirement.

In some embodiments, the curable binder precursor is a urethane prepolymer.

Examples of useful urethane prepolymers include, but are not limited to, polyisocyanates and blocked versions thereof. Typically, blocked polyisocyanates are substantially unreactive to isocyanate reactive compounds (e.g., amines, alcohols, thiols) under ambient conditions (e.g., temperatures in a range of from about 20 °C to about 25 °C), but upon application of sufficient thermal energy, the blocking agent is released, thereby generating isocyanate functionality that reacts with the amine curative to form a covalent bond.

Useful polyisocyanates include, for example, aliphatic polyisocyanates (e.g., hexamethylene diisocyanate or trimethylhexamethylene diisocyanate); alicyclic polyisocyanates (e.g., hydrogenated xylylene diisocyanate or isophorone diisocyanate); aromatic polyisocyanates (e.g., tolylene diisocyanate or 4,4'-diphenylmethane diisocyanate); adducts of any of the foregoing polyisocyanates with a polyhydric alcohol (e.g., a diol, low molecular weight hydroxyl group-containing polyester resin, and/or water); adducts of the foregoing polyisocyanates (e.g., isocyanurates, biurets); and mixtures thereof.

Useful commercially available polyisocyanates include, for example, those available under the trade designation ADIPRENE from Chemtura Corporation, Middlebury, Connecticut (e.g., ADIPRENE L 0311, ADIPRENE L 100, ADIPRENE L 167, ADIPRENE L 213, ADIPRENE L 315, ADIPRENE L 680, ADIPRENE LF 1800A, ADIPRENE LF 600D, ADIPRENE LFP 1950A, ADIPRENE LFP 2950A, ADIPRENE LFP 590D, ADIPRENE LW 520, and ADIPRENE PP 1095); polyisocyanates available under the trade designation MONDUR from Bayer Corporation, Pittsburgh, Pennsylvania (e.g., MONDUR 1437, MONDUR MP-095, or MONDUR 448); and polyisocyanates available under the trade designations AIRTHANE and VERSATHANE from Air Products and Chemicals, Allentown, Pennsylvania (e.g., AIRTHANE APC-504, AIRTHANE PST-95A, AIRTHANE PST-85A, AIRTHANE PET-91 A, AIRTHANE PET- 75D, VERSATHANE STE-95A, VERSATHANE STE-P95, VERSATHANE STS-55, VERSATHANE SME-90A, and VERSATHANE MS-90A).

To lengthen pot-life, polyisocyanates such as, for example, those mentioned above, may be blocked with a blocking agent according to various techniques known in the art. Exemplary blocking agents include ketoximes (e.g., 2-butanone oxime); lactams (e.g., epsilon-caprolactam); malonic esters (e.g., dimethyl malonate and diethyl malonate); pyrazoles (e.g., 3,5-dimethylpyrazole); alcohols including tertiary alcohols (e.g., t-butanol or 2,2-dimethylpentanol), phenols (e.g., alkylated phenols), and mixtures of alcohols as described. Exemplary useful commercially available blocked polyisocyanates include those marketed by Chemtura Corporation under the trade designations ADIPRENE BL 11, ADIPRENE BL 16, ADIPRENE BL 31, ADIPRENE BL 46, and ADIPRENE BL 500; and blocked polyisocyanates marketed by Baxenden Chemicals, Ltd., Accrington, England under the trade designation TRIXENE (e.g., TRIXENE BL 7641, TRIXENE BL 7642, TRIXENE BL 7772, and TRIXENE BL 7774).

Typically, the amount of any urethane prepolymer present in the curable binder precursor is in an amount of from about 10 to about 40 percent by weight, particularly in an amount of from about 15 to about 30 percent by weight, and even more particularly in an amount of from about to about 25 percent by weight based on the total weight of the curable binder precursor, although amounts outside of these ranges may also be used.

Exemplary curatives for urethane prepolymers include aromatic, alkyl-aromatic, or alkyl polyfunctional amines, preferably primary amines. Examples of useful amine curatives include 4,4'-methylenedianiline; polymeric methylene dianilines having a functionality of 2.1 to 4.0 which include those known under the trade designations

CURITHANE 103, commercially available from the Dow Chemical Company, and MDA- 85 from Bayer Corporation, Pittsburgh, Pennsylvania; l,5-diamine-2-methylpentane; tris(2-aminoethyl) amine; 3-aminomethyl-3,5,5-trimethylcyclohexylamine (i.e., isophoronediamine), trimethylene glycol di-p-aminobenzoate, bis(o- aminophenylthio)ethane, 4,4'-methylenebis(dimethyl anthranilate), bis(4-amino-3- ethylphenyl)m ethane (e.g., as marketed under the trade designation KAYAHARD AA by Nippon Kayaku Company, Ltd., Tokyo, Japan), and bis(4-amino-3,5- diethylphenyl)m ethane (e.g., as marketed under the trade designation LONZACURE M- DEA by Lonza, Ltd., Basel, Switzerland), and mixtures thereof. If desired, polyol(s) may be added to the curable binder precursor, for example, to modify (e.g., to retard) cure rates as required by the intended use. The amine curative should be present in an amount effective (i.e., an effective amount) to cure the blocked polyisocyanate to the degree required by the intended application; for example, the amine curative may be present in a stoichiometric ratio of curative to isocyanate (or blocked isocyanate) in a range of from 0.8 to 1.35; for example, in a range of from 0.85 to 1.20, or in a range of from 0.90 to 0.95, although stoichiometric ratios outside these ranges may also be used. In one embodiment, the binder cures to be generally clear or colorless. A binder that cures to be generally clear or colorless is more easily colored to a desired selected color. A binder that cures to be generally clear or colorless may also accentuate decorative particles 24 of the cleaning article 10. A binder that may have a color or cloudiness may be difficult to achieve a desired color. Examples of binders that cure to be generally colorless include styrene-butadiene rubbers, acrylics, and epoxies.

In one embodiment, the surface coating 16 includes between about 25 and about 70% by weight binder, particularly between about 40 and about 70% by weight binder, and more particularly between about 50 and about 65% by weight binder. In one embodiment, the binder constitutes between about 30 and about 300 grams per square meter (GSM) wet basis weight of the cleaning article, particularly between about 60 and about 150 GSM wet basis weight of the cleaning article, and more particularly between about 75 and about 125 GSM wet basis weight of the cleaning article.

In one embodiment, various processing techniques may be applied to all or a portion of the binder in the base coating 14 or the surface coating 16 to enhance the resistance to wear. For example thermal curing, UV curing, or e-beam curing may be used with the appropriately selected resins. In this embodiment, uncured portions wear faster than cured portion.

The surface coating 16 includes a crosslinker to promote linking of the polymer chains. In one embodiment, the surface coating 16 includes between about 1 and about 20%) by weight crosslinker, particularly between about 2 and about 15%> by weight crosslinker, and more particularly between about 3 and about 9% by weight crosslinker. Examples of suitable crosslinkers include, but are not limited to, amino crosslinkers, such as: methylated melamine resins, mixed ether melamine resins, butylated melamine resins, urea resins, butylated urea resins, benzoguanamine resins, and glycoluril resins. Examples of commercially available crosslinkers include, but is not limited to: Cymel® 373 and 385, available from Allnex located in Overland Park, KS; Resimine 714, 730, 731, 735 and 740, available from King Industries, Inc. located in Norwalk, CT.

A thickener is included in the surface coating 16 to increase the viscosity of the surface coating composition. In one embodiment, the surface coating 16 includes between about 0.5 and about 3% by weight thickener, particularly between about 0.5 and about 2.5% by weight thickener and more particularly between about 0.5 and about 2% by weight thickener. Examples of suitable thickeners include, but are not limited to, cellulosic thickeners, silicone elastomers, synthetic polymers, chemical based thickeners and combinations thereof. An example of a commercially available cellulosic thickener includes, but is not limited to, CAB-O-SIL, available from Cabot Corporation located in Alpharetta, GA.

The surface coating 16 of the present invention includes decorative particles 24 to enhance the aesthetic appearance of the cleaning article 10. As mentioned above, the decorative particles 24 are compatible with the clear binder resin of the surface coating 16. The decorative particles may include, but are not limited to: glitter, synthetic minerals, and natural minerals. Examples of suitable glitters include, but are not limited to: polyester glitters, polypropylene glitters, polyethylene glitters, and combinations thereof. An example of a commercially available polyester glitter includes, but is not limited to, Silver Sparkle Flake, available from Meadowbrook Inventions, located in Bernardsville, NJ. FIG. 2 A shows a magnified view of a cleaning article 10 of the present invention having decorative glitter particles 24a in the surface coating. FIG. 2B is a microscopic photograph of a first embodiment of decorative particles on the cleaning article of the present invention. FIG. 2C is a microscopic photograph of a second embodiment of decorative particles on the cleaning article of the present invention. FIG. 3 shows a magnified view of a cleaning article 10 of the present invention having decorative plastic particles 24b in the surface coating.

In one embodiment, the surface coating 16 includes between about 2 and about 30% by weight decorative particles 24, particularly between about 2 and about 20% by weight decorative particles and more particularly between about 3 and about 10% by weight decorative particles. In one embodiment, the decorative particles include between about 1 and about 30 wt% of the cleaning article, particularly between about 3 and about 15 wt% of the cleaning article, and more particularly between about 4 and about 8 wt% of the cleaning article. In one embodiment, the decorative particles constitute between about 30 to about 300 grams per square meter (GSM) wet basis weight of the cleaning article, particularly between about 50 to about 200 GSM wet basis weight of the cleaning article, and more particularly between about 60 to about 150 GSM wet basis weight of the cleaning article. In one embodiment, the decorative particles are between about 30 to about 500 microns each in size, particularly between about 30 and about 300 microns in size, and more particularly between about 30 and about 200 microns in size.

In order for the decorative particles 24 to be retained on the cleaning article 10 while providing the desired aesthetic affect, the size of the decorative particles 24 can be chosen relative to the size of the fibers in the fiber web 22. In one embodiment, a ratio of fiber size to decorative particle size is between about 0.1 to about 5, particularly between about 0.1 and about 3, and more particularly between about 0.1 and about 2.

The base coating 14, the surface coating 16 or both may include optional additives. For example, the additives may be dispersed throughout the binder of the coatings or separately applied following application of the coating. Exemplary additives include, but are not limited to: a crosslinker, filler, catalyst, fragrance, perfume, microcapsules, antibacterial agents, antimicrobial agents, antifungal agents, antifoaming agents, thickeners, fillers, or abrasives. In one embodiment, including filler such as titanium dioxide in the surface coating 16 aids in covering the color substrate, which may be the color of a base coating 14.

It may be particularly advantageous to include abrasive particles 26 on the cleaning article 10 to enhance the scouring ability of the cleaning article 10. The abrasive particles 26 may be included in the base coating 14, the surface coating 16, or may be separately applied after application of the base coating 14 or the surface coating 16, if included. The abrasive particles 26 that may be used in the cleaning article 10 include all known abrasive materials as well as combinations and agglomerates of such materials. Suitable abrasive materials include inorganic materials, for example aluminium oxide (including ceramic aluminium oxide, heat-treated aluminium oxide, and white-fused aluminium oxide), silicon carbide, tungsten carbide, alumina zireonia, diamond, ceria, cubic boron nitride, silicon nitride, garnet, and combinations thereof. Suitable abrasive materials also include softer, less aggressive materials such as polymeric particles and crushed natural materials (for example, crushed nut shells). Suitable polymeric materials for the abrasive particles include poiyamide, polyester, polyvinyl chloride, poly(methacrylic) acid, polymethylmethacrylate, polycarbonate, polystyrene, and melanune-fomialdehyde condensates. The abrasive particles should have a particle size small enough to allow them to penetrate into the bonded web 12' and, subject to that, it is contemplated that abrasive agglomerates, for example those described in US-A-4 625 275 and 4 799 939, may also be used. In one embodiment, the average particle sizes of the abrasive particles 26 range from about 1 to about 2000 microns.

In one embodiment, when the abrasive particles 26 are included in the base coating 14 or the surface coating 16, the coating includes between about 22 and about 65 wt% abrasive particles 26, particularly between about 22 and about 50 wt% abrasive particles 26, and more particularly between about 22 and about 40 wt% abrasive particles 26.

In one embodiment, the abrasive particles 26 are added to the cleaning article 10 separately from the base coating 14 and the surface coating 16. In this case, the abrasive particles 26 are added in an abrasive coating 28 after application of the base coating 14. The abrasive coating 28 generally includes water, binder, abrasive particles 26 and pigment. In one embodiment, the abrasive coating 28 includes between about 10 and about 25 wt% water, particularly between about 15 and about 25 wt% water, and more particularly between about 28 and about 25 wt% water. In one embodiment, the abrasive coating 28 includes between about 10 and about 30 wt% binder, particularly between about 15 and about 30 wt% binder, and more particularly between about 20 and about 25 wt% binder. In one embodiment, the abrasive coating 28 includes between about 22 and about 65 wt% abrasive particles 26, particularly between about 22 and about 50 wt% abrasive particles 26, and more particularly between about 22 and about 40 wt% abrasive particles 26. In one embodiment, the abrasive coating 28 includes between about 0.2 and about 2 wt% pigment, particularly between about 0.5 and about 1.5 wt% pigment, and more particularly between about 0.6 and about 1 wt% pigment.

In one embodiment, the cleaning article 10 includes a nonwoven substrate. The base coating 14 is a prebond binder that serves to reinforce the fibers of the web together. In other words, without the base coating 14, the nonwoven substrate does not have the structural integrity to maintain its shape through use and the base coating 14 is essential to holding the structure of the nonwoven together. The surface coating 16 having the decorative particles 24 is applied over the base coating 14. The cleaning article 10 may also include abrasive particles 26 added in the base coating 14, the surface coating 16, or separately. One suitable method of making this embodiment is to roll coat the base coating 14 over the fibers of the nonwoven and then to spray coat the surface coating 16. It is understood that the base coating 14 penetrates within the fiber web 22 to secure and reinforce the web 22 creating a nonwoven article with structural integrity. Also, it is understood that the surface coating 16 is applied over the base coating 14 to cover the base coating 14. The surface coating 16 may also partially penetrate into the fibers of the web 22. To make the cleaning article 10 as previously discussed, the nonwoven can be prepared by first forming a fiber web 22 by using crimped staple fibers in a "Rando Webber" web-forming machine (available from Rando Machine Corporation, Macedon, NY). The binder is applied to the fibers the nonwoven web to facilitate bonding of the fibers at their mutual contact points by the base coating 14. In one embodiment, the binder is roll coated onto the web 22. This coated web is then oven-dried to cure the binder of the base coating 14. Then, the web 22 is spray coated with the surface coating 16, which includes the decorative particles 24. This coated web is then oven-dried to cure the binder of the surface coating 16.

In another embodiment, the nonwoven can be prepared by first forming a web by using crimped staple fibers in a "Rando Webber" web-forming machine (available from Rando Machine Corporation, Macedon, NY). The binder is applied to the fibers the nonwoven web to facilitate bonding of the fibers at their mutual contact points by the base coating 14. In one embodiment, the binder is roll coated onto the web 22. This coated web is then oven-dried to cure the binder of the base coating 14 (intermediated web). Then, the web is spray coated with the surface coating 16, which includes the decorative particles 24 sprayed independently in series with the surface coating 16 (decorative web). This coated web is then oven-dried to cure the binder of the surface coating 16. This can be done in one continuous process on a single process manufacturing line or can be broken down into several process steps in different manufacturing lines. The cleaning article 10 of the present invention is a decorative cleaning tool that can clean a surface while retaining the decorative particles and not adversely affecting the cleaning efficiency of the cleaning tool. One particularly suitable application for the cleaning article 10 is as a scouring article utilized in cleaning, scrubbing and scouring dishes, pots, and pans. Such a cleaning article is intended to be used in excess of 5 independent cleaning cycles. The presence of the decorative particles does not

substantially affect the ability of the cleaning article to clean, or scour, a surface. The decorative particles of the surface coating 16 substantially remain on the cleaning article 10 even after use. Loss of the decorative particles can be visually evaluated by putting the samples in a soap solution with intermediate stirring for about 30 minutes. The loose decorative particles which dislodge from the cleaning article are collected to estimate the percent loss of decorative particles when put in actual use.

Generally, any dislodged decorative particles are transferred to the surface being cleaned. In one embodiment, at least about 98%, at least about 95%, at least about 90%, at least about 80%), at least about 75%, at least about 60%>, and at least about 50% of the decorative particles remain on the cleaning article after use.

Although specific embodiments of this invention have been shown and described herein, it is understood that these embodiments are merely illustrative of the many possible specific arrangements that can be devised in application of the principles of the invention. Numerous and varied other arrangements can be devised in accordance with these principles by those of ordinary skill in the art without departing from the spirit and scope of the invention. Thus, the scope of the present invention should not be limited to the structures described in this application, but only by the structures described by the language of the claims and the equivalents of those structures.

Examples

The present invention is more particularly described in the following examples that are intended as illustrations only, since numerous modifications and variations within the scope of the present invention will be apparent to those skilled in the art. Unless otherwise noted, all parts, percentages, and ratios reported in the following examples are on a weight basis.

MATERIALS

TEST METHODS Schiefer Cut Test

Schiefer cut testing was performed to evaluate the relative abrasiveness of the glitter coated nonwoven scouring materials. The test was performed in a generally similar manner as described in U.S. Patent No. 5,626,512 (Palaikis et al). The nonwoven scouring materials tested were cut into circular pad (8.25 cm in diameter). The test was conducted with the nonwoven scouring pad rotating at 250 rpm for 5000 revolutions under a load of 2.25 kg with water applied to the surface of the circular acrylic work piece (10.16 cm in diameter) at a rate of 40-60 drops per minute. Results are given as the weight loss of the acrylic work piece and are reported as grams per 5000 revolutions. Results are reported for the two major surfaces (top and bottom) of each of the nonwoven scouring pads tested.

Gardner Wear Test Wear testing was performed to evaluate the durability of the glitter coated nonwoven scouring materials. In this test the nonwoven scouring material was rubbed against an abrasive surface with the weight loss (of the nonwoven scouring material) noted after the test. Wear testing was performed in a generally similar manner as described in U.S. Patent No. 5,681,361 (Sanders, Jr.) with the differences being that the test sample size was a 8.5 cm x 8.5 cm, the abrading material was a 220 Grit Abrasive Belt (having aluminum oxide particles), the downward load applied to the test sample was 2.25 kg, and the results are reported as weight loss in grams per 50 cycles (back and forth equals 1 cycle).

Cleaning Efficiency Test

A 5.08 cm x 22.86 cm 18 gauge stainless steel panel was coated with a food soil mixture made up of 120 grams milk, 60 grams cheddar cheese, 120 grams hamburger, 120 grams tomato juice, 120 grams cherry juice, 20 grams flour, and 100 granulated sugar, and one egg. The coated panel was baked in an oven at 230°C for one hour. The panel was alternately coated and baked three times. The coated panel was then placed in a tray containing approximately 250 ml of a 4% aqueous dishwashing soap solution. A 7.5 cm x 10.0 cm pad of the nonwoven scouring material was inserted into the holder of a Gardner Heavy Duty Wear Tester No. 250. The nonwoven scouring pad was then run back and forth on the coated panel under an applied force of 2.25 kg until the coated panel was clean (no coated material visually remained on the panel). The number of cycles (back and forth equals one cycle) required to result in a clean panel was recorded. The nonwoven scouring pad was removed from the holder and then washed thoroughly under running tap water, so that all the food particles which were entrapped in the pad were washed off. Excess water was then removed (by shaking), and the test was repeated with the next coated panel. The test was repeated until 8 panels were tested. The cleaning efficiency of the scouring pad is reported as the Percent Performance Yield.

Glitter Loss Estimation A 3 inch x 4 inch (7.6 cm x 10.2 cm) pad of the glitter coated nonwoven scouring material was used for this test. The initial weight of the pad was recorded (Al). One liter of a lukewarm (40°C) 2% aqueous dishwashing soap solution was prepared and stirred well to create a foamy solution. The pad was then immersed in the soap solution for a 30 minutes with moderate stirring so that the pad was not stationary in the soap solution. The pad was then removed from the soap solution and the pad was squeezed for about one minute so that any soap solution taken up by the pad was squeezed out of the pad and back into the soap solution in the test container.

The soap solution was then filtered through a fine gauge fabric into another container. The initial weight of the fabric in grams was noted. The fabric only allowed only the soap solution to pass through to the second container, whereas any solid material (glitter particles, loose minerals, fibers, etc.) remained on the fabric surface. The fabric having the filtered solid materials was then allowed to dry and the weight after drying in grams was noted in grams. The solid material (glitter particles, loose minerals, fibers, etc.) that had collected on the fabric was removed from the fabric and weighed. The weight in grams was recorded as (A2). The estimated % Glitter Loss based on the initial weight of the glitter coated nonwoven scouring nonwoven scouring pad was calculated as: % Glitter Loss = (A2/Al) x 100.

Example 1

A lofty nonwoven web was prepared from EXYLON PA66 nylon staple fibers.

The nonwoven web was formed on a conventional air-laying web forming machine (available from the Rando Machine Corporation of Macedon, New York, under the trade designation RANDO-WEBBER). The thickness of the nonwoven web was 12.03 mm and the area weight (basis weight) of the web was approximately 190 grams per square meter (gsm). The nonwoven web was then impregnated with a prebond resin solution (Formulation 1) using a standard two-roll coater. The coated web was then dried and the prebond resin cured by passing the coated web through an oven having a temperature ranging from 125-140°C, yielding a prebonded, lofty nonwoven web. The amount of prebond resin solution coated as dry solids was 322 gsm.

The resultant prebonded, lofty nonwoven web was then spray coated on both major surfaces (top and bottom) with a binder solution containing abrasive particles (Formulation 2) to a wet add-on basis weight of 460 gsm. The coated web was then dried and the binder cured by passing the web through an oven having a temperature ranging from 140-180°C to form a strong abrasive coating on the lofty nonwoven web.

The resultant abrasive particle coated web was then spray coated on both major surfaces (top and bottom) with a binder solution containing glitter particles (Formulation 3) to a wet add-on basis weight of 75 gsm. The coated web was then dried and the binder cured by passing the web through an oven having a temperature ranging from 140-180°C to form a glitter particle coating on the lofty nonwoven web.

Formulations 1, 2 and 3 are provided in Table 1.

TABLE 1

Example 2

Glitter coated nonwoven scouring pads were prepared as described for Example 1 except that the thickness of the nonwoven web was approximately 12.63 mm and the amount of ALBERDINGK U 9380 in Formulation 3 was 49.35 wt%. Example 3

Glitter coated nonwoven scouring pads were prepared as described for Example 1 except that the thickness of the nonwoven web was approximately 11.89 mm, the amount of ALBERDINGK U 9380 in Formulation 3 was 49.35 wt%, and the wet add-on basis weight of the binder solution containing glitter particles was 121 gsm.

The glitter coated nonwoven scouring pads of Examples 1-3 were evaluated using the test methods described above. SCOTCH-BRITE Heavy Duty Scouring Pads (11 mm approximate pad thickness) were also tested as control samples. Schiefer Cut Test and Gardner Wear Test results are provided in Table 2 and Table 3. The data in Table 3 was obtained after machine washing the nonwoven scouring pads for 2 hours. Cleaning Efficiency results are provided in Table 4. The glitter coated nonwoven scouring pads still had a good glitter appearance after testing.

TABLE 2

TABLE 3

TABLE 4

*Ratio = Number of Panels cleaned /Average number of cycles for each individual test sample

"Performance Yield (%) = (Ratio value of individual test sample/Ratio value of Control) x 100

Example 4

An additional example of a glitter coated nonwoven scouring pad was prepared as described for Example 1 and two test samples of this material were used for estimating the percent glitter loss using the Glitter Loss Estimation test described above.

Test Sample 1 : Al = 6.7582 grams; A2 = 0.0366 grams; estimated % Glitter Loss = 0.5416%

Test Sample 2: Al = 6.7582 grams; A2 = 0.0074 grams; estimated % Glitter Loss = 0.1095%

Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.

Claims

What is claimed is:

1. A cleaning article comprising:

a substrate; and

a base coating on at least a surface of the substrate; and

a surface coating disposed on the base coating, the surface coating comprising: water;

a binder;

a cross-linker;

a thickener; and

decorative particles,

wherein the decorative particles constitute between about 30 to about 300 grams per square meter wet basis weight of the cleaning article,

and wherein at least about 50% of the decorative particles remains on the cleaning article after use.

2. The cleaning article of claim 1, wherein the binder is selected from the group consisting of: polyurethane, polyester, acrylic, styrene butadiene, melamine formaldehyde resin, and combinations thereof.

3. The cleaning article of claim 1, wherein the surface coating comprises between about 5 and about 25% by weight water.

4. The cleaning article of claim 1, wherein the surface coating comprises between about 25 and about 70% by weight binder.

5. The cleaning article of claim 1, wherein the surface coating comprises between about 1 and about 20% by weight crosslinker.

6. The cleaning article of claim 1, wherein the surface coating comprises between about 2 and about 30% by weight decorative particles.

7. The cleaning article of claim 1, wherein the surface coating comprises between about 0.5 and about 3% by weight thickener.

8. The cleaning article of claim 1, wherein the decorative particles comprise between about 1 and about 30 wt% of the cleaning article.

9. The cleaning article of claim 1, wherein the binder constitutes between about 30 and about 300 grams per square meter wet basis weight of the cleaning article.

10. The cleaning article of claim 1, wherein the substrate comprises fibers.

11. The cleaning article of claim 10, wherein a ratio of fiber size to decorative particle size is between about 0.1 to about 2.

12. The cleaning article of claim 1, wherein the decorative particles are between about 30 to about 500 microns each in size.

13. The cleaning article of claim 10, wherein the fibers have a length of between about 20 and about 150 millimeters.

14. The cleaning article of claim 1, where a thickness of the cleaning article is between about 2 and about 50 millimeters.

15. The cleaning article of claim 1, where the cleaning article has a basis weight of between about 50 and about 1500 grams/meter².

16. The cleaning article of claim 1, where the substrate comprises a nonwoven web, foam, paper, fabric or combination thereof.

17. The cleaning article of claim 1, where the decorative particles comprise glitter, melamine minerals, natural minerals or combination thereof.

8. The cleaning article of claim 1, further comprising abrasive particles.