Abstract:
A device for activating a two component reaction system where the two reaction component are in separate containers with one container inside the other. A pressure differential between the pressure in the inner and outer containers is made so the inner container has the higher pressure. The inner container has a line around at least one part of the inner container and extends through the outer container. The line is aligned to tear the container when it is pulled.

Description:
BACKGROUND 
       [0001]    This invention relates to an activation device for activating a two component reaction system where the two reaction component are in separate containers with one container inside the other. An example of such a reaction system is a system for heaters of personal hygiene wipes or cloths used to cleanse various parts of the body. More particularly, the invention relates to an improved activation device package for a personal hygiene wipe or cloth that is temperature controlled to give increased comfort and utility. 
         [0002]    Personal hygiene wipes are often used by persons when they are away from their home and do not have access to a shower or bath. They are also used when the part of the person that is to be cleaned is small, and a shower or bath consumes too much time. 
         [0003]    In order to be effective, however, personal hygiene wipes need to be warmed or heating in order to more effectively clean the hands or other parts of the user&#39;s anatomy. At the present time, warm wipes are only attainable by the use of an external source of hot water, or by inserting the wipes into a microwave or other heating device. This presents a danger as the degree of heating may vary, and it is possible to have excessive heat applied to the skin. 
         [0004]    A major drawback of the use of an exothermic reaction to generate heat upon demand is that the various components have to be kept totally separated from each other until they are combined, and when combined need to react quickly and over a reasonable surface area. If the reaction only takes place at one location, excessive heat will be generated. If the reaction components are spread out, there has not been any way to combine them from the dispersed locations to generate uniform exothermic reaction. The problem that occurs is that the heater gives too much heat to part of the object to be heated and too little to other parts. 
         [0005]    Yet another drawback to chemical generation of heat is that the reaction depends on adequate mixing that does not happen quickly enough to be useful. 
         [0006]    It would be a great advantage if a way of bringing a two component reaction system together to react in a quick and effective manner. 
         [0007]    Another advantage would be to provide a way of bringing a two component reaction system together that is controlled and requires a specific action by the user such that the action is not one experienced by the system when carried about prior to use. 
         [0008]    Yet another advantage would be to provide a way to activate a heater to generate heat by an exothermic reaction over a personal hygiene wipe sized area quickly, without having to wait for an activation agent to make its way to all the reaction components. 
         [0009]    Other advantages will appear hereinafter. 
       SUMMARY 
       [0010]    It has now been discovered that the above and other advantages of the present invention may be accomplished in the following manner. The unique aspect of this invention is the placement of one reaction component of a two component reaction system inside one container and the second reaction component inside a second container that is inside the first container. An actuation device is provided to open the inner container so the reaction can be effectively activated in a simple manner. Specifically, the activation device comprises a line or cord on the inner container that extends through the outer container, whereby pulling on the line causes the line to open the inner container. In a preferred embodiment, the inner container is made of a foil type material that is torn by pulling on the line. 
         [0011]    The invention uses a two component activation device such as those used for a heater in a package holding personal hygiene wipes. Other two component reaction systems, such as, by way of example and not by way of limitation, are systems where the reaction absorbs heat or effectively provides a cooling effect. Another example of a two component system is one that keeps an adhesive such as an epoxy resin separate from the catalyst that causes it to react until the time for bonding something is at hand. Cosmetics, edible products, medicines and diet supplements are other examples of products that it may be desirable to mix quickly, particularly mixing a solid and a liquid. 
         [0012]    The device of this invention allows the activation of the reaction when the user decides the time has come to do so. There is, in the preferred embodiment, a pressure differential between the outer container at a lower pressure than the inner container so that the reaction agent is thrust out of the inner container into contact with the reaction component inside the outer container. The outer container may have an internal vacuum sufficient to pull the activation agent into the outer container upon opening said seal. Alternatively, the inner container may have a pressure above atmospheric pressure to accomplish the same rapid mixing. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]      FIG. 1  is a perspective view of the device of this invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0014]    The device of this invention,  10  generally, is shown in  FIG. 1  and includes an outer container  11  having a first reaction component  13  therein. Also inside the outer container  11  is inner container  16  having a second reaction component  17  therein. Part of the inner container  16  is an activation element  27 , described in more detail below. In order to have an uniform and even mixing of the two reaction components, it is preferred that the inside of inner pouch  23  be at atmospheric pressure or 14.7 psi, and the inside of the outer pouch  19  be under vacuum. Preferred pressures in outside pouch  19  are from about 8 psi to about 13 psi, with 10 or 11 psi being preferred. It is necessary to have a pressure differential between the inside of both pouches to be sufficient to pull the activating agent  25  to the entire area where the heat generating material  21  has been placed. Alternatively, the inner pouch can have an increased pressure of from about 17 to 22 psi, and preferably from about 19 to 20 psi. Too little or too great a pressure differential is not desired, for design and reliability reasons. 
         [0015]    Attached to the inner container  16  is a line  19 . Line  19  can be any size or shape as long as it is capable of causing the inner container  16  to tear open when the end  21  of line  19  is pulled. In a preferred embodiment, inner container  16  is made from a heat stamp foil that is moisture impervious and that tears or rips when the line  19  is pulled. 
         [0016]    Preferred is an outer pouch  11  made from Aclar®, which is a polychlorotrifluoroethylene (PCTFE) material manufactured and sold by Honeywell International Inc. Aclar film is crystal clear, biochemically inert, chemical-resistant, nonflammable, and plasticizer- and stabilizer-free. Aclar laminates provide a wide range of gauges and thus barrier levels to allow flexibility in selecting the optimum barrier level for the chemical system chosen. Other similar pouch materials may be used as well. All that is required is that the material have a functional moisture and vapor barrier for the other components of the invention. 
         [0017]    The preferred embodiment is shown in  FIG. 1 , where line  19  encircles inner container  16  and also passes through the periphery  18  thereof. Periphery  18  is not in communication with the contents of container  16 . Periphery  18  includes holes  23  and  25 , which do not disturb the contents  17 . Line  19  has been looped completely around container  16 , back through hole  23  and out to end  21 . Pulling on end  21  of line  19  causes the loop portion of line  19  to tighten and tear inner container  16 , thus activating the reaction between reaction components  13  and  17 . This reaction is accelerated by the vacuum inside container  11 . 
         [0018]    There are a number of combinations of heat generating materials and activating agents that are suitable for use in the present invention. The selection of specific components is to be based upon cost, compatibility, ease of control of the exotherm, and other factors. 
         [0019]    The preferred activating material of this invention is water. This is plentiful and safe, and reacts with a number of materials to produce an exothermic reaction. 
         [0020]    The preferred heat generating material is a crystal that, when free from moisture, is stable for up to three to five years or more, and which react when moisture is present to generate heat. The preferred crystal is made from crystalline calcium oxide. Calcium oxide is commercially available from a number of sources, one of which being Calcium Oxide Fisher Scientific S79946. For efficient integration of this component into the fabric, the calcium oxide is ground into small particles or crystals and a sieve is used to insure uniform particle size. 
         [0021]    The weight of the heat generating material to the volume of actuation agent ranges from about 1:2 to about 1:1, and preferably about 3:4. In the most preferred mixture of the heat generating material is a mixture of calcium oxide and citric acid with the further addition of a zeolite powder. Preferred is a ratio of calcium oxide to citric acid to powdered zeolite is from about 14 to 20 for calcium oxide, from about 1 to 2 for citric acid, and from about 7 to 10 for powdered zeolite. Most preferred is a ratio of calcium oxide to citric acid to powdered zeolite is 17:1.5:8.5 and the ratio of the solids to the volume of water is about 3:4. 
         [0022]    More than 150 zeolite types have been synthesized and 48 naturally occurring zeolites are known. They are basically hydrated alumino-silicate minerals with an “open” structure that can accommodate a wide variety of positive ions, such as Na+, K+, Ca 2 +, Mg 2 + and others. These positive ions are rather loosely held and can readily be exchanged for others in a contact solution. Some of the more common mineral zeolites are: analcime, chabazite, heulandite, natrolite, phillipsite, and stilbite. An example mineral formula is: Na 2 Al 2 Si 3 O 10 -16H 20 . 
         [0023]    In order to have an uniform and even production of heat from the exotherms, it is preferred that the inside of inner pouch  16  be at atmospheric pressure or 14.7 psi, and the inside of the outer pouch  11  be under vacuum. Preferred pressures in outside pouch  11  are from about 8 psi to about 13 psi, with 10 or 11 psi being preferred. It is necessary to have a pressure differential between the inside of both pouches to be sufficient to pull the activating agent  17  to the entire area where the heat generating material  17  has been placed. Too little or too great a pressure differential is not desired, for design and reliability reasons. 
         [0024]    In a series of tests of the preferred embodiment as described above using water to react with calcium oxide, 100% of the activations by bending the packages resulted in warm personal hygiene wipes. Then a similar set of packages were prepared, with the only change being no vacuum inside the outer pouch, only 30% of the wipes achieved the desired temperature, 
         [0025]    It is also an embodiment of the present invention to employ a temperature changing chemical that causes a drop in temperature when contacted by water, creating an endothermic reaction. The solid materials may, for example, include materials such as sodium sulfate* 10H 2 O; sodium bicarbonate, ammonium nitrate, ammonium chloride, urea, ammonium dichromate, citric acid, potassium perchlorate, potassium sulfate, potassium chloride, calcium nitrate, and vanillin. These solid compounds react with water in an endothermic fashion to impart cooling. Reactions can be with water based mixtures as well as other liquid systems. Other uses of the activation of a two component reaction system 
         [0026]    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.