Abstract:
There is provided an apparatus for treating garments and fabrics in a dry or wetted state or in an aqueous liquid. The apparatus has an apertured rotating barrel which hold the garments or fabric. A microprocess in association with a plurality of valves selectively admits oxidizing gas, or, steam and liquid into the barrel to desize and/or discolor the garments or fabrics.

Description:
FIELD OF THE INVENTION 
     This invention relates to an apparatus for the treatment of fabrics with oxidizing gases. More particularly, there is provided an apparatus for treating fabrics in an extraction stage of a laundering operation with oxidizing gases such as ozone so as to decolorize dyes or coloring agents on the fabrics. The fabrics can be dry, wetted or in aqueous liquid. 
     BACKGROUND OF THE INVENTION 
     The present invention is an improvement over the apparatus disclosed in U.S. Pat. No. 5,313,811, which is herein unincorporated by reference. The prior art apparatus requires a venturi system for introducing oxidizing gases into the processing vessel. Consequently, sufficient water must be present in order that a pump can push the water throughout the system, generate a vacuum and draw the oxidizing gas into the return pipe where it is blended with water and returned to the processing vessel. 
     In the cases where a desizing or abrasion step is run before or in conjunction with the oxidation, large amounts of dye are suspended in the water to operate the venturi. Therefore, the oxidizing agent attacks the dye in the return line between the venturi and the processing vessel. This occurrence decreases the efficiency in desizing and decolorizing garments or fabrics and increases the requirement for more oxidizing agent. Additionally, flowing water is required so that decolorization cannot be provided for dry or wetted garments. 
     Various other systems have been developed to treat fabric or garments with ozone. The systems generally use steam mixed with ozone enriched air or oxygen and the fabric or garments are suspended in a treatment chamber. The steam has the function of wetting the fabric or garments and to elevate the temperature to increase the reaction rate. 
     U.S. Pat. No. 1,823,352 to Crespi et al discloses an apparatus for bleaching textile fibers with a gaseous current, such as ozonized air. In the apparatus, textile material is suspended in a chamber where it is acted on by a gaseous ozonized air mixture which passes through the chamber. 
     U.S. Pat. No. 4,283,251 to Singh discloses a process relating to the ozone and peroxygen bleaching of cellulosic pulp. The process includes the steps of recycling extract effluent from the bleaching treatment. 
     U.S. Pat. No. 4,300,367 to Thorsen discloses the treatment of fibers with ozone—steam mixtures by conveying them through an open-ended chamber. The fibers are exposed to the ozone—steam mixture in the horizontal middle section of the chamber where the ozone is centrally introduced. 
     U.S. patent application Ser. No. 460,357 of Hall et al, which is herein incorporated by reference, discloses the fading of dyed cellulosic garments by the ozone degradation of the dye without any substantial degradation of the cellulosic materials in a vapor phase. 
     It should be understood that the term “dye” as used herein is meant to include any of the materials which are used to provide a color to a fabric such as conventional dyes, pigments, or the like. The term “fabric” as used herein is meant to include woven and non-woven cloth, knitted fabrics, garments, and the like. 
     A dry fabric or garment can contain up to about 5% moisture depending on atmospheric conditions. 
     SUMMARY OF THE INVENTION 
     In accordance with the invention there is provided a multi-purpose apparatus for laundering and selectively decolorizing a fabric, especially those containing cellulosic material having an oxidizable coloring agent such as a dye, pigment, organic or inorganic residues, and the like in a dry or wetted state or in a liquid. The fabric may comprise cotton, linen, or other bast fibers or rayon alone or in combination with other materials including natural and synthetic fibers, for example, wool, nylon, polyester, and the like. 
     The invention provides an apparatus for laundering and treating garments or fabrics with an oxidizing agent. The apparatus includes a housing having a chamber. The chamber contains a barrel or drum mounted for rotation in the chamber with means for rotating the barrel. Door means is provided on said housing for placing garments or fabrics into the chamber. Means is provided for introducing the oxidizing agent, which is a gas into the chamber. Pipe means associated with the chamber permits circulating the oxidizing gas into the chamber when required. There are means associated with the housing for introducing an aqueous fluid into the chamber and means for removing liquid from the chamber if required. The apparatus advantageously contains a microprocessor for selectively controlling the laundering cycles including washing, extracting, desizing, etc. with valves. 
     Advantageously, the oxidizing gas is introduced into the chamber through the door means. 
     The apparatus of the invention can be used to decolorize garments or fabrics having an oxidizable coloring agent by either placing an oxidizing gas in a liquid or treating the fabrics or garments with an oxidizing agent in a gaseous or vapor phase or both. 
     The apparatus is further capable of undergoing various laundering operations before or after treatment with an oxidizing agent, for example, desizing, extracting, washing and abrading. 
     The oxidizing agent can be gaseous or a liquid or a solid oxidant in a vapor state. Gaseous oxidizing agents include ozone, NOx and SOx. These gases can be used alone, in admixture or diluted with an inert or low reactive gas such as air. The oxidizing gases can be used in combination with steam or in an aqueous system. 
     The non-gaseous oxidants should be used in a vapor phase, preferably with wetted fabrics. More preferably, the non-gaseous oxidants are used in combination with steam. 
     The oxidant, for example, ozone primarily reacts with the colorant on the fabric when the fabric is wet. Therefore, the garment is wetted or treated in a wet state. The water content of the wetted fabric when treated is about 5 to 75% by weight, more preferably about 20 to 40% by weight or higher depending upon the degree of treatment, the type of oxidant and the effect desired. The process is performed in a chamber in which the oxidant is generally present in an amount of about 10 to 1000 mg. per liter, more preferably about 10 to 100 mg per liter. The temperature in the chamber of about 40 to 100 degrees C. Any excess oxidant emitted may be recycled back into the chamber or used to treat any effluent of the laundering process. 
     It is an object of the invention to provide an apparatus for use in a laundering operation to decolorize dyed garments or fabrics with an oxidant without degrading the fabric. 
     It is still further object of the invention to provide an apparatus for selectively and/or evenly decolorizing or fading dyed garments to produce fashion garments. 
     It is another object of the invention to provide an apparatus for use in a laundering operation which can desize, wash, extract and provide an oxidant to decolorize a colorant of a fabric or garment in a single chamber. 
     It is yet another object of the invention to provide an apparatus for decolorizing fabrics and garment where flowing water is not required. 
     Other objects and a fuller understanding of the invention will be had by referring to the following description and claims of a preferred embodiment, taken in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an isometric cross-sectional view of the apparatus of the invention, and 
     FIG. 2 is a front elevational view of a gas destruct apparatus of the invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Although specific terms are used in the following description for the sake of clarity, these terms are intended to refer only to the particular structure of the invention selected for illustration in the drawings and are not intended to define or limit the scope of the invention. 
     The apparatus of the invention will be next described in detail with reference to the annexed drawings. In the description that follows, the apparatus will be described particularly for use in connection with an oxidizing gas which is ozone. However, it should be understood that other types of oxidants may be utilized in the liquid as well as the vapor phase to decolorize the coloring agent present, particularly an oxidizable dye. Other suitable oxidants include chlorine, nitrous oxides and/or sulfur oxides. 
     As seen in FIGS. 1 and 2, an apparatus  10  of the invention includes a housing  11  having an ozone-resistant treatment chamber  22 . In the chamber  22  is an apertured drum or barrel  23  which is mounted on a shaft for rotation by a motor (not shown). The motor is preferably a variable speed motor with reverse capabilities. The variable speed motor allows a tumbling and extracting cycle. A gas-tight door  12  permits placement of garments or fabrics into the chamber. A door with a glass porthole is preferred so as to allow for inspection of the degree of decolorization of the fabric or garments. The door preferably is provided with at least on gas entry port  15 . 
     Associated with the chamber  22  is a hose with a valve  50  which is closed when a gas is present in the chamber. 
     Preferably, the barrel  23  is provided along its interior with structural ribs  25  to make the barrel rigid and provide a mechanism to aid in the tumbling of garments or fabric. The ribs  25  also aid in abrading of fabric or garments. The ribs  25  can function to abrade the fabric or garments to provide a fashion appearance to the fabric or garments. The ribs  25 , during a desize cycle assists in removing sizing in combination with an enzyme or ozone as the desizing agent. The ribs  25  also act as a tumbler during a washing cycle. Abrading means comprising roughening material such as abrasion panels may be provided on the ribs  25 , pumice stone or aluminum diamond plates may be used. 
     At the lower portion of the chamber  22  is a drain  42  to remove liquid from the chamber  22 . Associated with drain is a pipe  20  having a valve  21  for discharging liquid when it is opened and causing liquid to remain in the chamber  22  when closed. Water lines  46 ,  47  bring in hot or cold water into the chamber, as required. 
     At the upper portion of the chamber  22  is a vent pipe  13 , which allows oxidizing gas to escape at a controlled rate. Vent pipe  13  allows the oxidizing gas to flow to a flow control valve  18 . The flow control valve  18  remains in the normally open position until it receives a signal from a micro processor  41  that the apparatus is receiving oxidizing gases into the chamber  22 . At such time the flow control valve  18  closes to a predetermined setting to allow oxidizing gases to remain in the chamber  22  under greater concentration or under pressure. An additional vent pipe  13 A is used between the flow control valve  18  and an oxidizing gas destruction unit  37 . 
     The oxidizing gas destruction unit  37  consists of an oxidizing gas resistant material. It contains a heating element  40  usually located in the bottom of the unit. Above the heating element  40  is a bed  24  of various types of charcoal particles which aid in the destruction of the oxidizing gases. The oxidizing gas destruction unit  37  also contains a fan  38  which is powered by an electric motor  39 . The fan  38  and electric motor  39  provide a means to maintain a vacuum in the vessel  22 . This vacuum produced by the fan  38  and the electric motor  39  pulls the unexpended oxidizing gases through the destruction unit  37  thereby destroying any oxidizing gases prior to discharge through exhaust  38 A into the atmosphere. 
     The oxidizing gas destruction unit  37  is also utilized after the oxidizing gas cycle. In that after the oxidizing gas cycle, the chamber  22  must be purged of any remaining oxidizing gases. After the oxidation cycle, a signal is sent from the microprocessor  41  to the flow control valve  18  to open. At the same time the microprocessor  41  also sends a signal to the drain valve  21  to open, thus allowing air to free-flow through the oxidizing gas destruction unit  37 . 
     The apparatus also includes a 3-way valve  17  for the introduction of oxidizing gases. In FIG. 1, an ozone generator  16  is used as the source of the oxidizing gas. The ozone gas under pressure moves from the generator  16  through ozone resistant piping  19  to the 3-way valve  17 . During the oxidizing step, the micro processor  41  sends a signal to the electrically or air operated 3-way valve  17  to open, allowing the ozone to flow through ozone resistant piping  33 , then through an ozone resistant swivel fitting  30 . The ozone resistant swivel fitting  30  is used to allow all of the piping  33 A to a second 3-way valve  43 . The 3-way valve  43  is used to determine the flow direction of the ozone from this point forward. In position “a” the 3-way valve  43  opens to allow the ozone gas to flow through ozone resistant piping  44 , through port  15  located at the lower part of the door  12  into process chamber  22 . The port  15  may consist of one or a multiple of port openings. In position “b” the 3-way valve  43  opens in the opposite direction to allow the ozone gas to flow through ozone resistant piping  45 , through port  15 A located at the upper part of the door  12  into process chamber  22 . The port  15 A may consist of one or a multiple of port openings. 
     The 3-way valve  17  in the normal position (not receiving a signal from the micro processor  41  allows the ozone to travel through the ozone resistant piping  34  to an additional 3-way valve  27 . The ozone may be diverted through ozone resistant piping  36  into the vent line  13 A then into the destruction unit  37 . The 3-way valve  27  in the alternative position may divert the ozone gas to different areas of use, such as water treatment (not shown). 
     The apparatus optionally includes a steam jacket  48  and a port  49  for manually adding chemicals. A steam line may also be included to maintain water temperature during the process cycle if a higher temperature is required by the wash formula. 
     The microprocessor  41  provides electronic control of the valves, water, ozone, etc., depending upon the different operation required. For example, the apparatus can be operated to extract, wash, emit steam alone or with the oxidizing gas. 
     The following chart shows the arrangement of the valves during an ozone decolorization process of wetted garments and during their process  14  steps. 
     
       
         
               
               
               
               
               
               
               
             
               
               
               
               
               
               
               
             
           
               
                   
                   
               
               
                   
                 Micro-Pro 
                   
                   
                   
                   
                   
               
               
                   
                 Signal 
                 Valve 17 
                 Valve 43 
                 Valve 21 
                 Valve 18 
                 Valve 27 
               
               
                   
                   
               
             
             
               
                   
               
             
          
           
               
                 Formula Step: 
                   
                   
                   
                   
                   
                   
               
               
                 Desize w/o ozone 
                 No Signal 
                 Closed to 
                 N/A 
                 Closed 
                 Open 
               
               
                   
                   
                 Apparatus 
               
               
                 Desize w/ozone 
                 Signal 
                 Open to 
                 Open to 
                 Closed 
                 Closed 
                 N/A 
               
               
                   
                   
                 Apparatus 
                 15 or 15A 
               
               
                 Decolorize w/o 
                 No Signal 
                 Closed to 
                 N/A 
                 Closed 
                 Open 
               
               
                 ozone 
                   
                 Apparatus 
               
               
                 Decolorize w/ozone 
                 Signal 
                 Open to 
                 Open to 
                 Closed 
                 Closed 
                 N/A 
               
               
                   
                   
                 Apparatus 
                 15 or 15A 
               
               
                 Purge-after either 
                 Signal 
                 Closed to 
                 N/A 
                 Open 
                 Open 
                 N/A 
               
               
                 ozone step 
                   
                 Apparatus 
               
               
                   
               
               
                 *Valve 27 can be placed to either position without effect on the ozone process during the entire application. Valve 27 controls the ozone to the destruct unit or to elsewhere in the facility.  
               
               
                 **Valve 18 in the closed position means closed approximately 87% to still allow for sufficient vacuum by the destruction unit to keep the apparatus from becoming pressurized.  
               
             
          
         
       
     
     Although the invention has been described with a certain degree of particularity, it is understood that the present disclosure has been made only by way of example and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention.