Patent Publication Number: US-2005125926-A1

Title: Cleaning article with indicator

Description:
TECHNICAL BACKGROUND  
      The present invention generally relates to a cleaning article for cleaning applications, and more specifically, to a cleaning article comprising an indicator, wherein the indicator wears due to continuous use to convey to the user that the cleaning article has met its useful lifespan and needs to be replaced.  
     BACKGROUND OF THE INVENTION  
      The general use of woven and nonwoven fabrics as cleaning and cleansing articles is well known in the art. Various end-use articles are commercially available which utilize a combination of topical, performance enhancing additives and/or multi-layered laminate constructions. Enhanced versions of articles used in cleaning applications further incorporate an optional cleaning fluid, including but not limited to, soaps, lotions, disinfectants, polishing solutions, and glass cleaners.  
      Disposable cleaning articles with indicators or sensors are also known. Usually such cleaning articles signal the user that the functional cleaning additive has been exhauster or that the cleaning article has come in contact with a substance that triggers the sensor. U.S. Pat. No. 6,501,002, to Roe, et al., discloses a disposable surface cleaning article having a sensor which detects bodily waste contamination on a surface and which provides a signal indicating the presence of such contamination. U.S. Pat. No. 4,678,704, to Fellows, discloses a cleaning article comprising an active agent along with an indicator dye that fades to indicate exhaustion of the active component.  
      Often, disposable cleaning articles are still usable even after the active component has been depleted. Dry disposable cleaning articles may be utilized for several days as well before actually needing to be discarded. Without an indicator present on the cleaning article, which conveys that the cleaning article has met or exceeded its useful life span, it&#39;s easy to lose track of how long the disposable cleaning article has been utilized.  
      A need remains for a disposable cleaning article that indicates when a disposable cleaning article has met or exceeded its useful life span. The present invention contemplates a cleaning article comprised of an indicator wears upon continuous use, notifying the user that it is time to replace the disposable cleaning article.  
     SUMMARY OF THE INVENTION  
      The present invention is directed to a cleaning article for cleaning applications, and more specifically, to a cleaning article comprising an indicator, wherein the indicator fades during use to convey to the user that the cleaning article has met or exceeded its useful life span and needs to be replaced.  
      In accordance with the present invention, the disposable cleaning article is comprised of a binder having a finite life span that acts as an indicator. Due to the continuous use of article the binder begins to fade and eventually is removed, indicating that usefulness of the disposable cleaning article has expired. The finite life span of the indicator is beneficial in a disposable cleaning article to act as a reminder to replace the expended cleaning article with a fresh article.  
      In a first embodiment, a portion of the disposable cleaning article is permanently imprinted with a symbol, language, or other indicator that notifies the user to dispose of the cleaning article. The permanent print is covered or otherwise obscured by a finite life span binder, which will fade due to continuous use over a pre-determined length of time so as to reveal the permanent print beneath the finite life span binder, signaling the user to replace the cleaning article.  
      In a second embodiment, a portion of the disposable cleaning article is permanently imprinted with an outline of a symbol or unspecified language that notifies the user to dispose of the cleaning article. As the finite life span binder begins to expire, the binder will eventually be removed due to use leaving behind the outline of the symbol or language, signaling the user to replace the cleaning article.  
      In a third embodiment, the finite life span binder is applied to the cleaning article in a gradient or scale-like formation, whereby the finite life span binder slowly fades due to use along the scale. Optionally, the scale may be broken down into separate colors indicating when the cleaning article is fresh, slightly used, and needs replacing.  
      The disposable cleaning article may be one or more layers of woven and/or nonwoven fabric, as well as film, and not meant to be a limiting factor of the present invention. Further, the disposable cleaning article may be coated and/or impregnated with an aqueous or non-aqueous cleaning composition; however the indicator of the disposable cleaning article functions independently from the amount of cleaning composition present in the disposable cleaning article.  
      Other features and advantages of the present invention will become readily apparent from the following detailed description, the accompanying drawings, and the appended claims. 
    
    
     DETAILED DESCRIPTION  
      While the present invention is susceptible of embodiment in various forms, there is shown in the drawings and will hereinafter be described a presently preferred embodiment of the invention, with the understanding that the present disclosure is to be considered as an exemplification of the invention, and is not intended to limit the invention to the specific embodiment illustrated.  
      The disposable cleaning article of the present invention may be one or more layers, wherein the layers may be selected from the group consisting of wovens, nonwovens, such as spunlace, spunbond, meltblown, air laid, wet laid, and films or a combination thereof. Manufacture of the cleaning article embodying the principles of the present invention may include providing the fibrous matrix, which can include the use of staple length fibers, continuous filaments, and the blends of fibers and/or filaments having the same or different composition. Fibers and/or filaments are selected from natural or synthetic composition, of homogeneous or mixed fiber length. Suitable natural fibers include, but are not limited to, cotton, wood pulp and viscose rayon. Synthetic fibers, which may be blended in whole or part, include thermoplastic and thermoset polymers. Thermoplastic polymers suitable for blending with dispersant thermoplastic resins include polyolefins, polyamides and polyesters. The thermoplastic polymers may be further selected from homopolymers; copolymers, conjugates and other derivatives including those thermoplastic polymers having incorporated melt additives or surface-active agents. Staple lengths are selected in the range of 0.25 inch to 10 inches, the range of 1 to 3 inches being preferred and the fiber denier selected in the range of 1 to 22, the range of 2.0 to 8 denier being preferred for general applications. The profile of the fiber and/or filament is not a limitation to the applicability of the present invention.  
      Spunlace fabrics, otherwise known as hydroentangled fabrics, are known in the art and disclosed in U.S. Pat. No. 3,485,706, to Evans, hereby incorporated by reference. The hydroentanglement of fibers or filaments of the fabric acts to provide the fabric with a useful level of integrity. Subsequent to entanglement, fabric integrity can be further enhanced by the application of binder compositions and/or by thermal stabilization of the entangled fibers or filaments.  
      Spunlace fabrics may be made in accordance with the apparatus shown in FIG. 1, whereby the apparatus includes a foraminous forming surface in the form of belt  12  upon which the precursor web P is positioned for entangling or pre-entangling by manifold  14 .  
      The entangling apparatus of FIG. 1 may optionally include an imaging and patterning drum  18  comprising a three-dimensional image transfer device for effecting imaging and patterning of the lightly entangled precursor web. The image transfer device includes a moveable imaging surface which moves relative to a plurality of entangling manifolds  22  which act in cooperation with three-dimensional elements defined by the imaging surface of the image transfer device to effect imaging and patterning of the fabric being formed.  
      A spunbond process involves supplying a molten polymer, which is then extruded under pressure through a large number of orifices in a plate known as a spinneret or die. The resulting continuous filaments are quenched and drawn by any of a number of methods, such as slot draw systems, attenuator guns, or Godet rolls. The continuous filaments are collected as a loose web upon a moving foraminous surface, such as a wire mesh conveyor belt. When more than one spinneret is used in line for the purpose of forming a multi-layered fabric, the subsequent webs is collected upon the uppermost surface of the previously formed web. The web is then at least temporarily consolidated, usually by means involving heat and pressure, such as by thermal point bonding. Using this means, the web or layers of webs are passed between two hot metal rolls, one of which has an embossed pattern to impart and achieve the desired degree of point bonding, usually on the order of 10 to 40 percent of the overall surface area being so bonded.  
      A related means to the spunbond process for forming a layer of a nonwoven fabric is the melt blown process. Again, a molten polymer is extruded under pressure through orifices in a spinneret or die. High velocity air impinges upon and entrains the filaments as they exit the die. The energy of this step is such that the formed filaments are greatly reduced in diameter and are fractured so that microfibers of finite length are produced. This differs from the spunbond process whereby the continuity of the filaments is preserved. The process to form either a single layer or a multiple-layer fabric is continuous, that is, the process steps are uninterrupted from extrusion of the filaments to form the first layer until the bonded web is wound into a roll.  
      The present invention also contemplates the use of sub-denier, as well as nano-denier filaments within the cleaning article. Nano-denier continuous filaments preferably have a denier of less than or equal to 1000 nanometers, and preferably have a denier less than or equal to about 500 nanometers.  
      Suitable nano-denier continuous filament layers can be formed by either direct spinning of nano-denier filaments or by formation of a multi-component filament that is divided into sub-denier filaments prior to deposition on a substrate layer. U.S. Pat. Nos. 5,678,379 and No. 6,114,017, incorporated herein by reference, exemplify direct spinning processes practicable in support of the present invention. Multi-component filament spinning with integrated division into sub-denier filaments can be practiced in accordance with the teachings of U.S. Pat. Nos. 5,225,018 and No. 5,783,503, incorporated herein by reference.  
      One or more layers of woven or nonwoven fabric may be used in combination with a film layer in formation of the cleaning article. Various film layers may include, cast films, extruded films, and reticulated films. Extruded films utilizing the composition of the present invention can be formed in accordance with the following representative direct extrusion film process. Blending and dosing storage comprising at least one hopper loader for thermoplastic polymer chip and, optionally, one for pelletized additive in thermoplastic carrier resin, feed into variable speed augers. The variable speed augers transfer predetermined amounts of polymer chip and additive pellet into a mixing hopper. The mixing hopper contains a mixing propeller to further the homogeneity of the mixture. Basic volumetric systems such as that described are a minimum requirement for accurately blending the additive into the thermoplastic polymer. The polymer chip and additive pellet blend feeds into a multi-zone extruder. Upon mixing and extrusion from the multi-zone extruder, the polymer compound is conveyed via heated polymer piping through a screen changer, wherein breaker plates having different screen meshes are employed to retain solid or semi-molten polymer chips and other macroscopic debris. The mixed polymer is then fed into a melt pump, and then to a combining block. The combining block allows for multiple film layers to be extruded, the film layers being of either the same composition or fed from different systems as described above. The combining block is connected to an extrusion die, which is positioned in an overhead orientation such that molten film extrusion is deposited at a nip between a nip roll and a cast roll.  
      In addition, breathable films, such as monolithic and microporous films, or reticulated films, can also be used within the cleaning article. Monolithic films, as taught in U.S. Pat. No. 6,191,211, and microporous films, as taught in U.S. Pat. No. 6,264,864, both patents herein incorporated by reference, represent the mechanisms of forming such breathable barrier films. Reticulated films, such as those of U.S. Pat. Nos. 4,381,326 and No. 4,329,309, are representative of macroporous films.  
      In accordance with the present invention, the disposable cleaning article is comprised of a binder having a finite life span that acts as an indicator. Due to the continuous use of article the binder begins to fade and eventually is removed, indicating that usefulness of the disposable cleaning article has expired. The finite life span of the indicator is beneficial in a disposable cleaning article to act as a reminder to replace the expended cleaning article with a fresh article. One example of a binder with a finite lifespan is a cross-linked starch-latex co-polymer.  
      In a first embodiment, a portion of the disposable cleaning article is permanently imprinted with a symbol, language, or other indicator that notifies the user to dispose of the cleaning article. The permanent print is covered or otherwise obscured by a finite life span binder, which will fade due to continuous use over a pre-determined length of time so as to reveal the permanent print beneath the finite life span binder, signaling the user to replace the cleaning article.  
      In a second embodiment, a portion of the disposable cleaning article is permanently imprinted with an outline of a symbol or unspecified language that notifies the user to dispose of the cleaning article. As the finite life span binder begins to expire, the binder will eventually be removed due to use leaving behind the outline of the symbol or language, signaling the user to replace the cleaning article.  
      In a third embodiment, the finite life span binder is applied to the cleaning article in a gradient or scale-like formation, whereby the finite life span binder slowly fades due to use along the scale. Optionally, the scale may be broken down into separate colors indicating when the cleaning article is fresh, slightly used, and needs replacing.  
      The cleaning article embodying the principles of the present invention is especially suitable for home care cleaning or cleansing articles. The nonwoven article may be used in various home care applications, wherein the end use article may be a dry or wet hand held sheet, such as a wipe, a mitt formation, or a cleaning implement capable of retaining the article. The various end uses are suitable for cleaning household surfaces such as, kitchen and bathroom countertops, sinks, bathtubs, showers, appliances, and fixtures.  
      It is within the purview of the present invention that the cleaning article may be utilized in a wet or dry state. An aqueous or non-aqueous cleaning composition may be topically applied or impregnated into the cleaning article. Cleansing compositions suitable for such end use applications include those that are described in U.S. Pat. Nos. 6,103,683 to Romano, et al., No. 6,340,663 to Deleo, et al., No. 5,108,642 to Aszman, et al., and No. 6,534,472 Arvanitidou, et al., all of which are hereby incorporated by reference. Selected cleaning compositions may also include surfactants, such as alkylpolysaccharides, alkyl ethoxylates, alkyl sulfonates, and mixtures thereof; organic solvent, mono- or polycarboxylic acids, odor control agents, such as cyclodextrin, peroxides, such as benzoyl peroxide, hydrogen peroxide, and mixtures thereof, thickening polymers, aqueous solvent systems, suds suppressors, perfumes or fragrances, and detergent adjuvants, such as detergency builder, buffer, preservative, antibacterial agent, colorant, bleaching agents, chelants, enzymes, hydrotropes, and mixtures thereof. The aforementioned compositions preferably comprise from about 50% to about 500%, preferably from about 200% to about 400% by weight of the nonwoven cleaning article.  
      The cleaning article embodying the principles of the present invention is also suitable for personal cleaning or cleansing articles. Nonlimiting examples of such applications include dry or wet facial wipes or sponges, body wipes or sponges, and baby wipes. Suitable methods for the application of various aqueous and non-aqueous compositions comprise aqueous/alcoholic impregnates, including flood coating, spray coating or metered dosing. Further, more specialized techniques, such as Meyer Rod, floating knife or doctor blade, which are typically used to impregnate cleansing solutions into absorbent sheets, may also be used.  
      Cleansing compositions suitable for such personal end use applications include, but are not limited to exfollients, anti-acne agents, anticaking agents, antioxidants, binders, chemical additives, natural additives, colorants, cosmetic astringents, cosmetic biocides, drug astringents, emulsifiers, humectants, skin bleaching agents, skin-conditioning agents (emollient, humectants, miscellaneous, and occlusive), skin protectants, solvents, foam boosters, hydrotropes, solubilizing agents, suspending agents (nonsurfactant), sunscreen agents, ultraviolet light absorbers, and viscosity increasing agents (aqueous and nonaqueous).  
      In addition to home care and personal care end uses, the nonwoven cleaning article may be used in industrial applications. For instance, the article may be useful in cleaning outdoor surfaces, such as lawn furniture, grills, and outdoor equipment. Aqueous or non-aqueous functional industrial solvents include, oils, such as plant oils, animal oils, terpenoids, silicon oils, mineral oils, white mineral oils, paraffinic solvents, polybutylenes, polyisobutylenes, polyalphaolefins, and mixtures thereof, toluenes, sequestering agents, corrosion inhibitors, abrasives, petroleum distillates, and the combinations thereof.  
      From the foregoing, numerous modifications and variations can be effected without departing from the true spirit and scope of the novel concept of the present invention. It is to be understood that no limitation with respect to the specific embodiment disclosed herein is intended or should be inferred. The disclosure is intended to cover, by the appended claims, all such modifications as fall within the scope of the claims.