Patent Application
20080083432
The invention relates to methods and apparati for laundering fabric where the wash step can be comprised of a combination of steps involving different working fluids such as an aqueous, non-aqueous, or combination working fluid.
The present invention relates to a program of events, ingredients, controls, and sensors that make it possible to produce a laundering machine that is self-contained, automatic, and relatively compact. It can be used in the home, lightly in industry as well as commercially, and is capable of utilizing a complete aqueous cycle, a semi-aqueous cycle, or a non-aqueous cycle. Additionally, the present invention describes a method of drying fabric that contains water and a soil. The machine offers the consumer the ability not only to launder their traditional fabrics (cotton, polyesters, etc.) at home, but also have the ability to handle delicate fabrics such as dry-clean only fabrics, nano-coated fabrics, and fabrics that contain electronics as well.
Water, as a cleaning solvent itself, has many benefits as well as disadvantages. Water is useful as a cleaning agent for many soils especially hydrophilic soils and provides excellent solubility characteristics with conventional detergent formulations. However, water is responsible for damage (shrinkage and wrinkling) to many of the traditional garments laundered at home. Additionally, water is very polar causing it to hydrogen bond readily, has a high heat capacity, and a low vapor pressure making it difficult to remove from fabric without adding a lot of energy either in terms of heat or centrifugation.
On the contrary to aqueous-based cleaning, there have been numerous attempts at making a non-aqueous laundering system; however, there have been many limitations associated with such attempts. Traditional dry-cleaning solvents such as perchloroethylene are not feasible for in-home applications because they suffer from the disadvantage of having perceived environmental and health risks. Fluorinated solvents such as hydrofluoroethers have been proposed as potential solvents for such an application. These solvents are environmentally friendly, have high vapor pressures leading to fast drying times, and provide some level of cleaning, but have some limitations with hydrophilic stain removal.
Other solvents have been listed as potential fluids for such an application. Siloxane-based materials, glycol ethers, and hydrocarbon-based solvents all have been investigated. Typically, these solvents are combustible fluids but the art teaches some level of soil removal. However, since these solvents are combustible and usually have low vapor pressures, it would be difficult to dry with traditional convection heating systems. The solvents have low vapor pressures making evaporation slow; thus increasing the drying time needed for such systems. Currently, the National Fire Protection Association has product codes associated for flammable solvents. These safety codes limit the potential heat such solvents could see or the infrastructure needed to operate the machine. In traditional washer/dryer combination machines, the capacity or load size is limited based on the drying rate. However, with the present invention, the capacity of the machines will be more dependent upon the size of the drum than the size of the load.
The present invention uses some of these aforementioned solvents to clean fabrics without the drying problems associated with these solvents. This is accomplished by using a non-flammable, non-aqueous working fluid that solves many of these drying problems. This system incorporates a process wherein water or other polar solvents could be used as cleaning fluids and traditional means for removing the aqueous solvent from the fabric such as convection based drying methods could be utilized. This present invention also allows for a non-aqueous drying means for these aqueous cleaning solvents. Additionally aqueous and non-aqueous solvents can be combined giving the consumer the semi-aqueous option of cleaning with an aqueous solvent for superior hydrophilic soil removal, cleaning with a non-aqueous fluid for superior hydrophobic soil removal, and then drying with one or more non-aqueous fluids to provide reasonable drying/cycle times. Further the consumer can select a complete non-aqueous cycle wherein a non-aqueous fluid cleans the fabric and the same or an additional non-aqueous fluid is used for drying.
U.S. Pat. No. 5,498,266 describes a method using petroleum-based solvent vapors wherein perfluorocarbon vapors are admixed with petroleum solvent vapors to remove the solvents from the fabrics and provide improvements in safety by reducing the likelihood of ignition or explosion of the vapors. However, the long-term stability of these mixtures is unknown but has the potential of separating due to dissociating the separate components.
U.S. Pat. No. 6,045,588 describes a method for washing, drying and recovering using an inert working fluid. Additionally, this application teaches the use of liquid extraction with an inert working fluid along with washing and drying.
U.S. Pat. No. 6,558,432 describes the use of a pressurized fluid solvent such as carbon dioxide to avoid the drying issues. In accordance with these methods, pressures of about 500 to 1000 psi are required. These conditions would result in larger machines than need be for such an operation. Additionally, this is an immersion process that may require more than one rinse so additional storage capacity is needed.
US Patent Publication Number 20030084588 describes the use of a high vapor pressure, above 3-mm Hg, co-solvent that is subjected to lipophilic fluid containing fabric articles. While a high vapor pressure solvent may be preferred in such a system, US 20030084588 fails to disclose potential methods of applying the fluid, when the fluid should be used, methods minimizing the amount of fluid needed as well as potential use of aqueous fluids as well.
Various perfluorocarbons materials have been employed alone or in combination with cleaning additives for washing printed circuit boards and other electrical substrates, as described for example in U.S. Pat. No. 5,503,681. Spray cleaning of rigid substrates is very different from laundering soft fabric loads. Moreover, cleaning of electrical substrates is performed in high technology manufacturing facilities employing a multi-stage that is not readily adaptable to such a cleaning application.
U.S. Pat. No. 5,888,250 describes a biodegradable ether solvent which may be used as a dry cleaning solvent or as a solvent for completing non-aqueous cleaning in the home.
US Patent Publication Number 20030046963 is a patent application disclosing a machine that can be preprogrammed to use a selective amount of water for laundering fabrics.
WO 0194675 describes the use of an apparatus capable of aqueous and non-aqueous methods for laundering. This application fails to teach any embodiments in which these methods can be easily practiced. Additionally, the solvent choices readily identified by this application, decamethylcyclopentasiloxane and water, are readily incompatible and for such a machine or method to work the apparatus would need to be equipped with separate hosing or involve a clean-out cycle between runs utilizing a solvent or water. This application differs from the present invention in that the present invention describes an additional semi-aqueous method plus describes methods in detail on how to minimize the cycle times for both aqueous and non-aqueous-based cleaning fluids.
US Patent Publication Number 20030196277 describes figures wherein an apparatus is capable of completing both a solvent-based cleaning and water washing process. This application fails to teach any embodiments wherein the aforementioned processes can be completed. The present invention not only discloses and teaches methods, chemistries, and apparatus wherein a non-aqueous and aqueous cleaning cycle are possible, but methods for minimizing solvent usage as well as processes for minimizing cycle time.
The disclosures and drawings of each of the above references are incorporated herein by reference.
An object of the present invention is to provide a complete sequence of laundering wherein the system can utilize an aqueous process, a semi-aqueous process, or a non-aqueous process while drying quickly.
A further object of the invention is the provision of a specific process wherein an aqueous wash is followed by a non-aqueous rinse to improve the cycle time by reducing the time needed to dry.
Another object of the invention is the provision of techniques and methods for minimizing the amount of non-aqueous fluid needed and the time that the non-aqueous fluid should be in contact with the fabric articles.
Another object of the invention is the provision of a low energy drying process that results in improved fabric care and shorter drying times.
Another object of the invention is the provision of recovery methods and techniques for the semi-aqueous and non-aqueous systems described in this invention.
A further object of the invention is the provision of a single apparatus with multiple working fluid options including water wherein the apparatus is designed to complete either an aqueous, semi-aqueous, or non-aqueous laundering methods, low temperature drying, and recovery methods.
A further object of the invention is the provision of means for concentrating and disposing of soils in an environmentally friendly manner.
It is a further object that the materials used are all of a type that avoids explosion and manages flammability hazards.
Another object of the present invention is the provision of means wherein the drying always occurs in the presence of a non-flammable fluid rich environment.
It is still a further object of the present invention that the consumer can select an aqueous cleaning cycle and a non-aqueous fast drying cycle.
Another object of the present invention is the provision of means whereby the consumer can select a non-aqueous fast drying cycle with a traditional hand/feel wherein moisture is added at the end of the cycle.
It is still a further object of the present invention to provide specific chemistries and materials that make the aqueous, semi-aqueous, and non-aqueous processes of the present invention possible.
Further objects and advantages of the invention will become apparent to those skilled in the art to which this invention relates from the following description of the drawings and preferred embodiments that follow:
The present invention significantly reduces drying time for fabrics and other porous materials containing an aqueous solvent, by solvent extracting the aqueous solvent from the material before subjecting it to a drying gas. In addition, the invention reduces shrinkage. The present invention also relates to a two-stage solvent extraction of an aqueous solvent from fabrics and the like before drying. The two-stage extraction allows the first stage extraction to use liquids that are effected in removing an aqueous solvent but have properties that do not allow for faster drying. The second extraction is used to replace the first extraction fluid with one that is faster drying and safe at elevated temperatures. It is believed that the aqueous solvent bridges hydrogen bonded fibers together, and when the aqueous solvent is evaporated during drying it pulls the fibers close together. The present invention replaces the aqueous solvent with a non-aqueous liquid; so that when the non-aqueous liquid is removed, less shrinkage ensues.
Modifications of the machine shown in U.S. Patent Application 20040117919 has been used to test the efficacy of the washing and recovery operations of the present invention and which are described in the following specification are incorporated herein by reference.
Patent application Ser. No. 10/956,707 describes a similar technique utilizing a select rinse fluid and is therefore, included herein for reference.
Figures in both the aforementioned cases (US 20040117919 and 10/956,707) show machines that can be used for techniques described in this invention. In the instance for both an aqueous and non-aqueous working fluid, it should be noted that the dispensers might be separate for each classification of fluid, chambered separately within the same housing, or be the same dispenser. The key features would be sensing technology that would recognize the differences that exist between the working fluid's detergent formulation; thus indicating to the consumer that the wrong detergent type has been entered.
One embodiment of the present invention could comprise a consumable detergent composition comprising a surfactant capable of enhancing soil removal benefits and additionally being dissolved in either aqueous and/or non-aqueous working fluid, an aqueous and/or non-aqueous fluid, optionally other cleaning adjuncts capable of enhancing soil removal. The aqueous fluid, non-aqueous fluids and cleaning adjuncts which could be utilized in such a consumable composition will be discussed later in the specification. In addition, the constituents of the composition can be compounded within the confines of the machine.
The heater should be controlled in such a way that it can be operated regardless of the working fluid selected for operation. If the working fluid selected has a flash point, the heater should regulate the system to control the temperature to 30° F. below the flash point of the working fluid if the concentration of the working fluid exceeds 0.25% of its lower flammability limit or the oxygen concentration is greater than 8%.
Other condensing methods not mentioned may be utilized for such an invention. The condenser can be additionally selected from air to air heat exchangers, cold wire inserts, tube bank heat exchanger, cross-flow, counter flow, tube and shell, impinging jets, evaporative cooling, spray droplets, trickle beds, condensing spinning discs, cooling towers, thermoelectric or combinations thereof. The cooling medium can be air, water, refrigerant, or the working fluid. The condenser should be designed to handle multiple fluids and separate multiple fluids upon condensation.
The washing additive can be selected from the group consisting of: builders, surfactants, enzymes, bleach activators, bleach catalysts, bleach boosters, bleaches, alkalinity sources, antibacterial agents, colorants, perfumes, pro-perfumes, finishing aids, lime soap dispersants, composition malodor control agents, odor neutralizers, polymeric dye transfer inhibiting agents, crystal growth inhibitors, photobleaches, heavy metal ion sequestrants, anti-tarnishing agents, anti-microbial agents, anti-oxidants, linkers, anti-redeposition agents, electrolytes, pH modifiers, thickeners, abrasives, divalent or trivalent ions, metal ion salts, enzyme stabilizers, corrosion inhibitors, diamines or polyamines and/or their alkoxylates, suds stabilizing polymers, solvents, process aids, fabric softening agents, optical brighteners, hydrotropes, suds or foam suppressors, suds or foam boosters, fabric softeners, antistatic agents, dye fixatives, dye abrasion inhibitors, anti-crocking agents, wrinkle reduction agents, wrinkle resistance agents, soil release polymers, soil repellency agents, sunscreen agents, anti-fade agents and mixtures thereof.
The wash liquor is preferably a combination of a working fluid and optionally at least one washing additive. The chamber by its rotation adds mechanical energy 206 to the combination of the working fluid and fabric. The mechanical energy may be of the form of, but is not limited to, tumbling, agitating, impelling, nutating, counter-rotating the drum, liquid jets that spray fluids thus moving the fabrics, vibrating, oscillating, or combinations thereof. This mechanical energy is one form for processing the fabric load. Other forms may include adding, mixing and removing the fabric load. The mechanical energy should be added continuously or intermittently for a time ranging from 2-120 minutes, but may be longer depending on the amount of cleaning needed. The wash liquor is then removed in step 208. Potential methods for removing the wash liquor include, but are not limited to, centrifugation, liquid extraction, the application of a vacuum, the application of forced heated air, capillarity, the application of pressurized air, simply allowing gravity to draw the wash liquor away from the fabric, the application of moisture absorbing materials or mixtures thereof.
After removing the wash liquor, the wash liquor is prepared for disposal, 210. This process may be different than traditional laundry processes of today in that this step involves determining the amount of non-aqueous contaminants that exist in the liquor make-up and determining whether this amount can or should be disposed of down the drain. In step 212, the contaminants are disposed. The contaminants can be disposed down the drain or collected in a filter device and then disposed of periodically. The periodic disposal gives the flexibility of the machine not having to be located close to a water source.
A preferred embodiment of such a technique is to add wash liquor to a fabric load, processing the fabric load resulting in a second wash liquor, measuring the concentration of a non-aqueous fluid (i.e. decamethylcyclopentasiloxane) in the second wash liquor, if the concentration exceeds a predetermined acceptable level (i.e. 2%) the processing the second wash liquor to form a third and optionally fourth wash liquors and then disposing of the wash liquors.
Additional aqueous working fluid can be added as a rinse fluid or as a second wash step in 214. The working fluid can be accompanied by washing additives and the wash liquor is then mixed with the fabric load through added mechanical energy, 216. The added mechanical energy is similar to that described above. The wash liquor is removed in 218 and all the remaining steps involving the removal of the working fluid from the fabric load can be accomplished via the aforementioned techniques.
The wash liquor is prepared for disposal in 220 and this can be similar to or different than the preparation technique in step 210 and disposed in 222. The number of rinses can vary and steps 214 through 222 can be repeated as often as necessary.
A drying gas is introduced in step 224 and the working fluid is removed from the fabric and routed through a condenser and condensed in step 226. The drying gas can be selected from, but is not limited to, the following: air, nitrogen, carbon dioxide, other inert gases, and mixtures thereof. The fluid condensed in step 226 is prepared for disposal in step 228. This step may be similar to or different from steps 210 and 220 mentioned above. The contaminants are collected and then disposed in step 230. The disposal of contaminants could occur together if necessary. This embodiment describes a condensing drying technique that would result in a dry fabric load, 232. It should be noted that an open-loop drying system might be utilized where the working fluid vapor removed from the fabric during the drying process is removed from the system via ventilation to an external environment. An open-loop system is only possible for an aqueous cycle with a traditional dry. Some embodiments may incorporate a condensing, closed-loop as well as open-loop system depending on the working fluid choice. Open-loop drying in meant to describe a technique which takes the air from the drum and vents it externally to the environment without passing through a scrubbing technique such as adsorption, absorption or filtration.
The process described in
Additives can be coupled with the non-aqueous working fluid to further enhance the removal of the aqueous working fluid, the soil removal and/or the reduction of cycle time. These additives can be similar to those added with the aqueous working fluid or different. The additive can be selected from the group consisting of: builders, surfactants, enzymes, bleach activators, bleach catalysts, bleach boosters, bleaches, alkalinity sources, antibacterial agents, colorants, perfumes, pro-perfumes, finishing aids, lime soap dispersants, composition malodor control agents, odor neutralizers, polymeric dye transfer inhibiting agents, crystal growth inhibitors, photobleaches, heavy metal ion sequestrants, anti-tarnishing agents, anti-microbial agents, anti-oxidants, linkers, anti-redeposition agents, electrolytes, pH modifiers, thickeners, abrasives, divalent or trivalent ions, metal ion salts, enzyme stabilizers, corrosion inhibitors, diamines or polyamines and/or their alkoxylates, suds stabilizing polymers, solvents, process aids, fabric softening agents, optical brighteners, hydrotropes, suds or foam suppressors, suds or foam boosters, fabric softeners, antistatic agents, dye fixatives, dye abrasion inhibitors, anti-crocking agents, wrinkle reduction agents, wrinkle resistance agents, soil release polymers, soil repellency agents, sunscreen agents, anti-fade agents, temperature, pressure and mixtures thereof. Mechanical energy may be applied in the form of, but not limited to, tumbling, agitating, impelling, nutating, counter-rotating the drum, liquid jets that spray fluids thus moving the fabrics, vibrating, oscillating, or combinations thereof is added to the drum, 216. The wash liquor is removed from the drum in step 218. The removed wash liquor is sent to the recovery system, 242, which will be described in greater detail later in the specification.
The addition of the non-aqueous working fluid to the drum can be completed prior to completing a series of one or more aqueous rinse steps. The non-aqueous working fluid addition can be completed one or more times to decrease the aqueous working fluid concentration below a set value or until enough soil has been removed. The longer contact time and the more the non-aqueous fluid used in the rinse, the lower concentration of the remaining non-aqueous fluid. A drying gas is passed over the fabrics in step 224. The drying gas can be selected from, but not limited to, air, nitrogen, carbon dioxide, other inert gases, and mixtures thereof. Optionally, the drying gas can be heated to improve the removal of the working fluids from the fabric. The drying gas containing working fluid vapor is then passed over a condenser and the working fluids are condensed, 226. The condensed fluids are then separated in 246 and dry fabric, 232, results when sufficient working fluid vapor has been removed from the fabric.
A further embodiment is described in
At least one washing additive can be added to the non-aqueous working fluid. This washing additive can be similar or different from the washing additive added with the aqueous working fluid. The washing additive can be selected from the group consisting of: builders, surfactants, enzymes, bleach activators, bleach catalysts, bleach boosters, bleaches, alkalinity sources, antibacterial agents, colorants, perfumes, pro-perfumes, finishing aids, lime soap dispersants, composition malodor control agents, odor neutralizers, polymeric dye transfer inhibiting agents, crystal growth inhibitors, photobleaches, heavy metal ion sequestrants, anti-tarnishing agents, anti-microbial agents, anti-oxidants, linkers, anti-redeposition agents, electrolytes, pH modifiers, thickeners, abrasives, divalent or trivalent ions, metal ion salts, enzyme stabilizers, corrosion inhibitors, diamines or polyamines and/or their alkoxylates, suds stabilizing polymers, solvents, process aids, fabric softening agents, optical brighteners, hydrotropes, suds or foam suppressors, suds or foam boosters, fabric softeners, antistatic agents, dye fixatives, dye abrasion inhibitors, anti-crocking agents, wrinkle reduction agents, wrinkle resistance agents, soil release polymers, soil repellency agents, sunscreen agents, anti-fade agents and mixtures thereof.
The next difference between
Even more specifically, the non-aqueous working fluid is selected from the group consisting of perfluorinated hydrocarbons, decafluoropentane, hydrofluoroethers, methoxynonafluorobutane, ethoxynonafluorobutane, carbon dioxide, ionic liquids, HFE-7300, and/or mixtures thereof. At least one washing additive can be added to the second non-aqueous fluid. These additives can be the same or different from those added in any of the previous steps. The washing additive can be selected from the group consisting of: builders, surfactants, enzymes, bleach activators, bleach catalysts, bleach boosters, bleaches, alkalinity sources, antibacterial agents, colorants, perfumes, pro-perfumes, finishing aids, lime soap dispersants, composition malodor control agents, odor neutralizers, polymeric dye transfer inhibiting agents, crystal growth inhibitors, photobleaches, heavy metal ion sequestrants, anti-tarnishing agents, anti-microbial agents, anti-oxidants, linkers, anti-redeposition agents, electrolytes, pH modifiers, thickeners, abrasives, divalent or trivalent ions, metal ion salts, enzyme stabilizers, corrosion inhibitors, diamines or polyamines and/or their alkoxylates, suds stabilizing polymers, solvents, process aids, fabric softening agents, optical brighteners, hydrotropes, suds or foam suppressors, suds or foam boosters, fabric softeners, antistatic agents, dye fixatives, dye abrasion inhibitors, anti-crocking agents, wrinkle reduction agents, wrinkle resistance agents, soil release polymers, soil repellency agents, sunscreen agents, anti-fade agents and mixtures thereof.
Mechanical energy is then added to the system. After a time sufficient to lower the concentration of the first non-aqueous working fluid to lower than 50% by mass of the fabric, more preferably less than 25% and most preferably less than 15%, the wash liquor is removed and sent to the recovery system. The remaining working fluid is removed via a drying gas. The vapors from the drying gas are condensed and the condensate is separated in step 250 into mostly aqueous working fluid, the first non-aqueous working fluid and the second non-aqueous working fluid.
Laundering fabric with water as the polar working fluid, removing a substantial portion of the water via centrifugation, contacting the fabric with dipropylene glycol n-butyl ether to provide additional cleaning of some hydrophobic soils as well as to remove some of the water that remains in the fabric, removing a substantial portion of the dipropylene glycol n-butyl ether, contacting the fabric with ethoxynonafluorobutane to remove a majority of the dipropylene glycol n-butyl ether and remaining water, centrifuging the fabric load, and then contacting the fabric with heated air to remove the remaining working fluids is a preferred embodiment. This particular method can take place in an apparatus designed for both aqueous and non-aqueous working fluid. In addition, due to the relative compatibility of the dipropylene glycol n-butyl ether, water and ethoxynonafluorobutane, a single plumbing system could be utilized.
Another preferred method includes laundering fabric with water as the polar working fluid, removing a substantial portion of the water via centrifugation, contacting the fabric with decamethylcyclopentasiloxane to provide additional cleaning of some hydrophobic soils as well as to remove some of the water that remains in the fabric, removing a substantial portion of the decamethylcyclopentasiloxane, contacting the fabric with ethoxynonafluorobutane to remove a majority of the decamethylcyclopentasiloxane and remaining water, centrifuging the fabric load, and then contacting the fabric with heated air to remove the remaining working fluids. In this system, due to the relative incompatibility of decamethylcyclopentasiloxane and water, separate aqueous and non-aqueous plumbing systems should be utilized in an apparatus designed to complete the aforementioned method.
In
At least one washing additive can be added to the non-aqueous working fluid. This additive can be similar or different than the additives mentioned above. The washing additive can be selected from the group consisting of: builders, surfactants, enzymes, bleach activators, bleach catalysts, bleach boosters, bleaches, alkalinity sources, antibacterial agents, colorants, perfumes, pro-perfumes, finishing aids, lime soap dispersants, composition malodor control agents, odor neutralizers, polymeric dye transfer inhibiting agents, crystal growth inhibitors, photobleaches, heavy metal ion sequestrants, anti-tarnishing agents, anti-microbial agents, anti-oxidants, linkers, anti-redeposition agents, electrolytes, pH modifiers, thickeners, abrasives, divalent or trivalent ions, metal ion salts, enzyme stabilizers, corrosion inhibitors, diamines or polyamines and/or their alkoxylates, suds stabilizing polymers, solvents, process aids, fabric softening agents, optical brighteners, hydrotropes, suds or foam suppressors, suds or foam boosters, fabric softeners, antistatic agents, dye fixatives, dye abrasion inhibitors, anti-crocking agents, wrinkle reduction agents, wrinkle resistance agents, soil release polymers, soil repellency agents, sunscreen agents, anti-fade agents and mixtures thereof.
A similar or different non-aqueous fluid can be added in step 240. If the non-aqueous fluid added in step 260 is flammable, then it is preferred that the non-aqueous fluid in step 240 is non-flammable. In addition to non-flammability, other characteristics ideal for the non-aqueous fluid include but are not limited to: vapor pressure higher than the vapor pressure added in step 260, surface tension lower than the surface tension of the non-aqueous fluid in step 260 and Hansen Solubility parameters selected from the following criteria: a polarity greater than about 3 and hydrogen bonding less than 9; hydrogen bonding less than 13 and dispersion from about 14 to about 17; or hydrogen bonding from about 13 to about 19 and dispersion from about 14 to about 22. The only remaining step that differs from
In almost every instance, the non-aqueous working fluids are more expensive than their aqueous counterparts. Therefore, minimizing non-aqueous working fluid is essential for apparatuses and methods involving these fluids. One potential method for minimizing fluid usage is through spray rinse or spray wash technology. Spray wash/rinse technology works by adding the non-aqueous working fluids while the drum is spinning at a force sufficient to move the fabrics toward the wall of the drum. This may occur at a force greater than 1G. Generally this force is at a spinning speed of at least 50-rpm, more preferably greater than 100 rpm and most preferably greater than 200 rpm. The time required is dependent upon the application but should be greater than 30 seconds and shouldn't exceed 15 minutes. The amount of non-aqueous fluid required is to provide sufficient soil removal or sufficient removal of other working fluids. This amount should be less than 10 liters of non-aqueous fluid per kilogram of fabric, more preferably less than 5 liters per kilogram of fabric and most preferably less than 2 liters per kilogram of fabric.
As has been mentioned throughout the specification, there are many potential cycles, 500, that can be utilized by the consumer.
The materials having a low boiling point solvent (i.e. less than 100° C.) are separated and recovered in step 604. Methods for separating the low boiling point non-aqueous fluids from the wash liquor include, but are not limited to: fractional distillation, temperature reduction, addition of a flocculating agent, adsorption/absorption, liquid extraction through the use of another additive, filtration, gravimetric separation, osmosis, evaporation, pervaporation, pressure increase, ion exchange resin, chemisorption, single stage distillation, multiple stage distillation or a combination of the aforementioned steps. The final low boiling non-aqueous fluid that is recovered and stored for reuse should contain less than 50% by weight impurities including other working fluids, more preferably less than 25% and most preferably less than 10%.
Dissolved soils include those items that are dissolved in the working fluid, such as oils, surfactants, detergents, etc. Mechanical and chemical methods or both may remove dissolved soils 606. Mechanical removal includes the use of filters or membranes, such as nano-filtration, ultra-filtration and microfiltration, and/or cross flow membranes. Pervaporation may also be used. Pervaporation is a process in which a liquid stream containing two or more components is placed in contact with one side of a non-porous polymeric membrane while a vacuum or gas purge is applied to the other side. The components in the liquid stream sorb into the membrane, permeate through the membrane, and evaporate into the vapor phase (hence the word pervaporate). The vapor, referred to as “the permeate”, is then condensed. Due to different species in the feed mixture having different affinities for the membrane and different diffusion rates through the membrane, a component at low concentration in the feed can be highly enriched in the permeate. Further, the permeate composition may differ widely from that of the vapor evolved in a free vapor-liquid equilibrium process. Concentration factors range from the single digits to over 1,000, depending on the compounds, the membrane and process conditions.
Chemical separation may include change of state methods, such as temperature reduction (e.g., freeze distillation), temperature increase, pressure increase, flocculation, pH changes and ion exchange resins.
Other removal methods include electric coalescence, absorption, adsorption, endothermic reactions, temperature stratification, third component addition, dielectrophoresis, high performance liquid chromatography, ultrasonic, and thermo-acoustic cooling techniques.
Insoluble soils 608 may include water, enzymes, hydrophilic soils, salts, etc. Items may be initially insoluble but may become soluble (or vice versa) during the wash and recovery processes. For example, adding dissolvers, emulsifiers, soaps, pH shifters, flocculants, etc., may change the characteristic of the item. Other methods of insoluble soil removal include filtration, caking/drying, gravimetric, vortex separation, distillation, freeze distillation and the like.
The step of concentrating impurities 610 may include any of the above steps done that are done to reduce, and thereby purify, the working fluid recovery. Concentrating impurities may involve the use of multiple separation techniques or separation additives to assist in reclamation. It may also involve the use of a specific separation technique that cannot be done until other components are removed.
In some instances, the surfactants may need to be recovered. A potential means for recovering surfactants is through any of the above-mentioned separation techniques and the use of CO2 and pressure.
As used herein, the sanitization step 612 will include the generic principle of attempting to keep the unit relatively clean, sanitary, disinfected, and/or sterile from infectious, pathogenic, pyrogenic, etc. substances. Potentially harmful substances may reside in the unit due to a prior introduction from the fabrics cleaned, or from any other new substance inadvertently added. Because of the desire to retrieve clean clothes from the unit after the cycles are over, the amount of contamination remaining in the clothes ought to be minimized. Accordingly, sanitization may occur due to features inherent in the unit, process steps, or sanitizing agents added. General sanitization techniques include: the addition of glutaraldehyde tanning, silver, formaldehyde tanning at acidic pH, propylene oxide or ethylene oxide treatment, gas plasma sterilization, gamma radiation, electron beam, ultraviolet radiation, peracetic acid sterilization, thermal (heat or cold), chemical (antibiotics, microcides, cations, etc.), and mechanical (acoustic energy, structural disruption, filtration, etc.).
Sanitization can also be achieved by constructing conduits, tanks, pumps, or the like with materials that confer sanitization. For example, these components may be constructed and coated with various chemicals, such as antibiotics, microcides, biocides, enzymes, detergents, oxidizing agents, etc. Coating technology is readily available from catheter medical device coating technology. As such, as fluids are moving through the component, the fluids are in contact with the inner surfaces of the component and the coatings and thereby achieve contact-based sanitization. For tanks, the inner surfaces of tanks may be provided with the same types of coatings thereby providing longer exposure of the coating to the fluid because of the extended storage times. Any coating may also permit elution of a sanitizer into the fluid stream. Drug eluting stent technology may be adapted to permit elution of a sanitizer, e.g., elution via a parylene coating.
The non-aqueous fluid-rich phase, 806, are treated in a similar manner as described in
It should be understood that lines could be single plumbed conduits and contain multiple coaxial lines within or a device for cleaning out a substantial portion of the working fluid to prevent cross contamination. Such lines make it possible for incompatible aqueous and non-aqueous fluids to be utilized within a single line plumbed apparatus.
It should be understood that fabric enhancement chemistries could be added at any time throughout the process. Some potential chemistries include but are not limited to: fabric softeners, viscosity thinning agents such as cationic surfactants, soil repellency agents, fabric stiffening agents, surface tension reducing agents and anti-static agents.
In some instances the working fluids are immiscible and the miscibility gap could be overcome by a change in temperature or the addition of one or more components.
In any of the aforementioned figures, heating may be supplied at any time to heat the machine, one or more machine components, the fluids, the fabric, air or a combination thereof.
In general, fabrics have a tendency to be damaged by temperatures exceeding 60° C. and most inlet air temperatures in traditional dryers may exceed 175° C. In traditional non-aqueous systems, the working fluids of choice usually have flashpoints lower than 100° C. In addition to the high flash points, these working fluids have low vapor pressures and they require higher temperatures for removal from the fabric. The National Fire Protection Association regulates the temperatures to which these working fluids may be heated to 30° F. below the flash point of the solvent.
A non-flammable fluid combined with a flammable fluid increases the flash point of the solvent; thereby, increasing the safety associated with the system. The non-flammable, non-aqueous working fluid will volatilize more quickly creating a non-flammable-rich headspace above the working fluid; and this greatly reduces fire and explosion hazards due to the wash medium used. While most of the existing codes are set only for commercial machines, the ability to use this apparatus and method in the home can be more easily adapted with the preferred rinse fluid method. The method has the capabilities of mitigating the risk associated with the use of cleaning with a flammable solvent.
The preferred apparatus for such an operation should contain a myriad of components and can be modular in nature if need be and has already been disclosed in patent application Ser. No. 10/971,671 which is included herein for reference. The apparatus should contain storage containers for the working fluid(s) as well as rinse fluid(s). The apparatus should contain a drum or container for depositing clothes a means for controlling the drum such as a motor, a means for dispensing the working fluids, washing additives and the likes into the wash chamber, a blower to move air for drying, a heating means for heating the air, the fluids, the fabrics or the drum, a condensing means to remove the solvent vapors from the air stream, a means to add mechanical energy to the drum, means for sensing, a means for recovery and a control means.
In a preferred embodiment, the apparatus would be constructed in a manner where the size wouldn't require modifications to place the unit within the home.
One of the main benefits in addition to drying time that resulted from an aqueous working fluid with a non-aqueous working fluid is low energy consumption. Aqueous working fluids generally have high heat capacity and hydrogen bond to the fabric load requiring excessive energy to be removed from the fabric load. On the other hand, non-aqueous working fluids have lower specific heats, lower heat capacity and don't hydrogen bond to the fabric lower thereby lowering the energy required for removal from the fabric load.
It should be noted that even though some of the figures show a horizontal axis fabric care machine, all of the described inventions above can be completed in a vertical axis machine, a cabinet apparatus, or any other apparati that can complete fabric cleaning or other substrate cleaning apparati such as hard surface cleaners.
In some instances, thermal management may be very effective in such a process. The motors turning the drum and operating the pump traditionally give off heat. This heat may be effectively used in heating the non-aqueous fluid for drying, spinning and/or heating the rinse fluid to promote increased cleaning. Additionally, some type of cooling mechanism is a preferred embodiment to the reclamation system and this cooling system can be interspersed throughout the product to provide more energy efficient heating and cooling.
It should also be noted that a machine of this kind would be new to the world and methods for selling, installing, servicing and marketing would need to be further described. An example would be a method of marketing fabric care material for use in conjunction with a laundry machine capable of utilizing an aqueous, semi-aqueous and/or non-aqueous working fluid comprising the steps of: identifying the desired consumer benefits; selecting a material to respond the consumer benefit; and optionally, distributing the fabric care material to a vendor. The fabric care materials can be combined and sold in kits and instructions for use can be provided. Selling such a machine may require professional installation and professional servicing as well.
The present application is a Continuation of U.S. patent application Ser. No. 11/135,181, entitled “A Multifunctioning Method Utilizing A Two Phase Non-Aqueous Extraction Process”, filed May 23, 2005 which is a Continuation-in-Part of U.S. patent application Ser. No. 10/957,555, entitled “Fabric Laundering Using a Select Rinse Fluid and Wash Fluids”, filed Oct. 1, 2004, which is a Continuation-in-Part of 10/699,159, filed Oct. 31, 2003. U.S. patent application Ser. No. 11/135,181 is related to the following applications of overlapping inventorship and common ownership hereof and filed the same day as: “Methods And Apparatus For Laundering With Aqueous And Non-Aqueous Working Fluids”, our docket number 20040195; “Methods And Apparatus To Accelerate The Drying Of Aqueous Working Fluids”, our docket number 20050054; “A Method For A Semi-Aqueous Wash Process And A Recovery Method Employing The Same”, our docket number 20050156; and “A Method For Fluid Recovery In A Semi-Aqueous Wash Process” our docket number 20050157. U.S. patent application Ser. No. 11/135,181 is also related to the following applications, the specifications and drawings of which are incorporated by reference: 10/957,484, “Method and Apparatus Adapted for Recovery and Reuse of Select Rinse Fluid in a Non-Aqueous Wash Apparatus” filed Oct. 1, 2004; 10/957,485 “A Fabric Laundering Apparatus Adapted for Using a Select Rinse Fluid, filed Oct. 1, 2004; 10/956,707 “A Method for Laundering Fabric with a Non-Aqueous Working Fluid Using a Select Rinse Fluid, filed Oct. 1, 2004; 10/957,451 “Non-Aqueous Washing Apparatus and Method, filed Oct. 1, 2004, 10/957,486 “Non-Aqueous Washing Apparatus and Method, filed Oct. 1, 2004; and 10/957,487 “Non-Aqueous Washing Machine and Methods”, filed Oct. 1, 2004.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 11135181 | May 2005 | US |
| Child | 11998082 | Nov 2007 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 10957555 | Oct 2004 | US |
| Child | 11135181 | May 2005 | US |
| Parent | 10699159 | Oct 2003 | US |
| Child | 10957555 | Oct 2004 | US |
