Abstract:
A disposable, solution-mixing hair colorant dispenser: tubular rear segment including first reservoir having rupturable front end; tubular middle segment including second reservoir having rupturable rear and front ends; tubular front segment including rear end and forward-projecting porous applicator. Rupturing member near adjacent ends of first and second reservoirs for rupturing both when first and second segments are engaged. Rupturing member near front end of second reservoir for rupturing same when second and third segments are engaged. Alternative rupturing members: double-ended between first and second reservoirs and single-ended attached to third segment; double-ended within second reservoir; single-ended within first reservoir and single-ended attached to third segment. Segments threaded for endwise engagement to seal segments and rupture reservoirs. Fluids mixed and dispensed through applicator.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates to mixing and dispensing small volumes of liquids (more particularly, hair colorants) and especially to a disposable handheld container having reservoirs for mixing hair colorant ingredients and an applicator for applying them to a person&#39;s hair.  
           [0003]    2. Description of the Related Art  
           [0004]    Coloring a person&#39;s hair may entail preparing an unstable mixture of two or more solutions and applying them to the hair in the short time before they lose their effectiveness. This commonly involves opening several containers, mixing their contents, and perhaps transferring the mixture to yet another container, preferably one having a spout or applicator, from which to pour, drip, or paint the mixture onto the hair. These steps waste time, effort, and material and make a mess.  
           [0005]    It would be helpful if the hair stylist could mix the solutions without pouring, apply the mixture without first transferring it, and dispose of the spent containers instead of cleaning and re-using them within the limited space available in most salons.  
           [0006]    What is needed is economy of steps, an inexpensive yet highly functional structure, and containment and facile disposal of waste.  
         SUMMARY OF THE INVENTION  
         [0007]    It is an object of the present invention to provide an inexpensive, disposable hair colorant dispenser which preserves separate components of a coloring solution until the time of use, mixes them without opening separate containers and pouring the contents back and fourth, and also functions as a tool for applying the mixture.  
           [0008]    It is an additional object of the present invention to provide such a dispenser in which fluid communication is reliably established between a plurality of compartments with simple manipulation of a clean, non-leaking container.  
           [0009]    In accordance with these objects and with others which will be described and which will become apparent, an exemplary embodiment of the hair colorant dispenser in accordance with the present invention comprises first, second and third segments;  
           [0010]    the first segment comprising a tubular housing having a rear end and having a ruputurable front end adapted for forcible engagement with the second segment, a first reservoir being defined in the first segment; a first rupturing means disposed within the first reservoir to rupture the front end when the first and second segments are forcibly engaged;  
           [0011]    the second segment comprising a tubular housing having ends to engage the first and third segments, a second reservoir being defined within the second segment, said second reservoir having rupturable rear and front ends, the rear end also being rupturable by the rupturing means of the first segment when the first and second segments are forcibly engaged;  
           [0012]    said third segment comprising a tubular housing, a front end defining an applicator, a rear end for forcible endwise engagement with the front end of the second segment, and second rupturing means attached to the rear end.  
           [0013]    Forcible engagement of the first and second segments lets fluid flow between the first and second reservoirs. Forcible engagement of the second and third segments lets fluid flow from the second reservoir to the applicator.  
           [0014]    It is an advantage of this embodiment that a single rupturing member reliably pierces two membranes and holds both open.  
           [0015]    In another exemplary embodiment of the hair colorant dispenser in accordance with the present invention, at least one of the first and second segments has sealing means for confining a fluid as they are engaged.  
           [0016]    In another exemplary embodiment, at least one of the three segments has such sealing means.  
           [0017]    In another exemplary embodiment, the front end surface of the first segment can be forced rearwardly onto the rupturing means.  
           [0018]    In another exemplary embodiment, the rupturing means has a sharp edge near the front end surface and is supported within the first reservoir so as to resist being pushed rearward when the front end surface is pushed rearward.  
           [0019]    In another exemplary embodiment, the applicator includes a porous wick.  
           [0020]    In another exemplary embodiment, the front end surface of the third segment is adapted for engagement with the front end surface of the second segment, so that the third segment can be mounted on the front end of the second segment for protection during shipment. It can be removed, reversed and re-attached for use.  
           [0021]    In another exemplary embodiment, the rear end surface of the third segment is securely and sealingly engageable with the front end surface of the second segment such that the second rupturing means projects rearward a sufficient distance to rupture the front end surface of the second segment, and the front end surface of the third segment is securely and sealingly engageable with the front end surface of the second segment such that clearance exists for the applicator to be disposed forward of the front end surface of the second segment.  
           [0022]    In another exemplary embodiment, each of the first and second rupturing means includes at least one base member fixed relative to the tubular housing and at least one cutting edge disposed distally on the base member. The cutting edge and base member cooperate, when fully engaged with the respective rear and front end surfaces of the second segment, to hold the ruptured surfaces open so that fluids may easily pass between the first, second, and third segments.  
           [0023]    In another exemplary embodiment, each of the first and second rupturing means includes several base members joined to form a common cutting edge and to define at least two fluid passages around the base members within the tubular housing.  
           [0024]    Another exemplary embodiment of a hair colorant mixing and dispensing apparatus in accordance with the present invetion comprises endwise serially sealingly engageable first, second and third tubular segments, a first rupturing means disposed between the first and second segments, and a second rupturing means disposed between the second and third segments;  
           [0025]    the first segment defining an interior including a first reservoir; the second segment defining an interior including a second reservoir; the third segment defining an interior including an applicator communicating with the interior;  
           [0026]    the first rupturing means comprising at least one stabilizing member for securing it to an end of at least one of the first and second segments;  
           [0027]    the first rupturing means comprising at least one cutting edge fixed to the at least one stabilizing member and disposed toward at least one of the respective ends of the first and second segments, the first rupturing means comprising at least one thrusting member contacting the at least one cutting edge;  
           [0028]    the first and second segments when so engaged defining a range of relative longitudinal displacement including first and second relative positions;  
           [0029]    engagement in the and second position and all in intermediate positions forming a seal between adjacent ends of the segments to prevent fluid leakage; engagement in the second position resulting in the transmission of force through the at least one thrusting member, thereby rupturing adjacent ends of said segments and holding open the ruptured ends to let fluid pass;  
           [0030]    the second rupturing means comprising at least one stabilizing member for securing the second rupturing means to an end of at least one of the second and third segments; the second rupturing means comprising at least one cutting edge fixed to the at least one stabilizing member and disposed toward the end of the second segment;  
           [0031]    the second rupturing means comprising at least one thrusting member contacting the at least one cutting edge;  
           [0032]    the second and third segments when so engaged defining a range of relative longitudinal displacement including first and second relative positions; engagement in the first, second and all intermediate positions forming a seal between adjacent ends of the segments to prevent fluid leakage;  
           [0033]    engagement in the second position resulting in the transmission of force through the at least one thrusting member thereby rupturing an end of the second segment and holding it open.  
           [0034]    Engagement of the first, second, and third segments in the second relative positions lets fluid flow between the first and second reservoirs and into the applicator.  
           [0035]    It is an advantage of this embodiment that forces are balanced between the cutting edges of the first rupturing member to assure that both membranes between the first and second reservoirs are opened.  
           [0036]    In another embodiment of the hair colorant dispenser in accordance with the present invention, the applicator comprises a porous wick.  
           [0037]    In another embodiment, the front end surface of the third segment is adapted for engagement with the front end surface of the second segment, whereby the third segment may be mounted on the front end of the second segment so that the applicator is adjacent the front end surface of the second segment for shipment and storage.  
           [0038]    In another embodiment, the rear end surface of the third segment is securely and sealingly engageable with the front end surface of the second segment so that the second rupturing means projects rearward a sufficient distance to rupture the front end surface of the second segment; and the front end surface of the third segment is likewise engageable with the front end surface of the second segment so that sufficient clearance exists for the applicator to be disposed forward of the front end surface of the second segment for shipment and storage.  
           [0039]    In another embodiment, each of the first and second rupturing means comprises a plurality of base members joined to form a common cutting edge and to define at least two fluid passages around the base members within the housing.  
           [0040]    In another embodiment, a first stabilizing member secures a first cutting edge to the first segment and a second stabilizing member secures a second cutting edge to the second segment.  
           [0041]    In another embodiment, a first stabilizing member secures a first cutting edge and a second cutting edge to one of the first and second segments.  
           [0042]    Another exemplary embodiment of a hair colorant mixing and dispensing apparatus in accordance with the present invetion comprises a first segment, a second segment, and a third segment;  
           [0043]    the first segment comprising a tubular body, a closed rear end, and an open front end, the tubular body and the front end being adapted for engagement with the second segment; a first reservoir being defined between the rear end and the front end within the body, the first reservoir comprising a frangible front membrane disposed proximate the front end of the first segment, the first reservoir being stiff enough to resist longitudinal compression;  
           [0044]    the second segment comprising a tubular body, an open rear end, and an open front end, the rear end being adapted for endwise engagement with the first segment, the front end being adapted for engagement with the third segment; a second reservoir being defined between the rear end and the front end within the body, the second reservoir comprising a frangible front membrane and a frangible rear membrane;  
           [0045]    rupturing means being disposed within the second reservoir and comprising a rear punch disposed proximate the rear end surface of the second reservoir and a front punch disposed proximate the front end surface thereof and longitudinally spaced apart a first length from the rear punch;  
           [0046]    the second reservoir being longitudinally compressible such that, when so compressed, the front membrane is disposed less than the first length from the rear membrane;  
           [0047]    the third segment comprising a tubular body; a front end defining an applicator, and an open rear end adapted for endwise engagement with the second segment;  
           [0048]    the first, second, and third segments cooperating, when engaged, to force the front membrane of the second reservoir rearwardly toward the front punch and to force the front membrane of the first reservoir and the rear membrane of the second reservoir forwardly toward the rear punch;  
           [0049]    whereby engagement of the first segment with the second segment lets fluid flow between the first reservoir and the second reservoir, and engagement of the second segment with the third segment lets fluid flow between the second reservoir and the applicator.  
           [0050]    It is an advantage of this embodiment that a single rupturing member is utilized to open all three membranes that must be opened to mix and dispense the contents. It is a further advantage that, because the rupturing member is contained within the second reservoir, it is unlikely to be lost or damaged.  
           [0051]    Another exemplary embodiment of a hair colorant dispenser in accordance with the present invention further comprises a connector disposed between the front punch and the rear punch for holding the first punch and the second punch in longitudinally spaced-apart relation.  
           [0052]    In another exemplary embodiment, the second reservoir defines at least one interior bracing surface and the front punch and the rear punch are supported by the interior bracing surface so as to resist the first punch and the second punch in longitudinally spaced-apart relation.  
           [0053]    Also in accordance with the same objects, an exemplary method of mixing and dispensing hair colorant in accordance with the present invention comprises the steps of:  
           [0054]    providing front, middle and rear serially endwise engageable tubular dispenser segments;  
           [0055]    providing first and second mixture components individually and separately sealed behind a plurality of membranes located in the rear and middle segments;  
           [0056]    providing at lest one cutter on at least one of the rear and middle segments, the at least one cutter having at least one force-balancing means assuring that the cutter encounters sufficient resistance penetrating each one of the membranes to be cut by the at least one cutter, that the at least one cutter will substantially open every one of the membranes;  
           [0057]    engaging the rear and middle segment to drive the at least one cutter to rupture the membranes and thereby to unseal and mix together the first and second mixture components;  
           [0058]    providing an applicator on the front segment; and  
           [0059]    engaging the middle and front segments to dispense the components through the applicator.  
           [0060]    Another exemplary method of mixing and dispensing hair colorant in accordance with the present invention includes the further step of providing a cutter on the front segment.  
           [0061]    It is an advantage of the present invention that all membranes that must be ruptured to mix and dispense the contents are reliably ruptured and held open to provide unimpeded fluid flow. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0062]    For a further understanding of the objects and advantages of the present invention, reference should be had to the following detailed description, taken in conjunction with the accompanying drawing, in which like parts are given like reference numbers and wherein:  
         [0063]    [0063]FIG. 1 is a perspective view of an exemplary embodiment of a hair colorant dispenser in accordance with the present invention;  
         [0064]    [0064]FIG. 2 is a side view thereof;  
         [0065]    [0065]FIG. 3 is a side sectional view thereof;  
         [0066]    [0066]FIG. 4 is a side sectional view thereof;  
         [0067]    [0067]FIG. 5 is a side sectional view thereof;  
         [0068]    [0068]FIG. 6 is a side view thereof;  
         [0069]    [0069]FIG. 7 is a side sectional view of an exemplary embodiment of a hair colorant dispenser in accordance with the present invention;  
         [0070]    [0070]FIG. 8 is a side sectional view thereof;  
         [0071]    [0071]FIG. 9 is a side sectional view thereof;  
         [0072]    [0072]FIG. 10 is a side sectional view of an exemplary embodiment of a hair colorant dispenser in accordance with the present invention;  
         [0073]    [0073]FIG. 11 is a side sectional view thereof;  
         [0074]    [0074]FIG. 12 is a side sectional view thereof;  
         [0075]    [0075]FIG. 13 is a side sectional view thereof; and  
         [0076]    [0076]FIG. 14 is a side sectional view thereof; 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0077]    The invention will now be described with reference to FIG. 1, which illustrates in perspective view a preferred embodiment of the hair colorant dispenser  40  (“dispenser”) in accordance with the present invention shown generally by the reference number  40  comprising a first segment  42 , a second segment  44 , and a third segment (not visible in FIG. 1) including a wick-like applicator  48  adapted for dripping, dabbing, or painting the liquid contents of the dispenser  40  onto a person&#39;s hair.  
         [0078]    [0078]FIG. 2, an enlarged side view of a preferred embodiment of the dispenser  40 , shows the first segment  42  including a closed first segment rear end  50  and a first segment front end  52 ; the second segment  44  including a second segment rear end  54  and a second segment front end  56 , and the applicator  48 . The first segment front end  52  is joined to the second segment rear end  54 . The applicator  48  projects forward and is disposed proximate the second segment front end  56 .  
         [0079]    [0079]FIG. 3, a side view of a preferred embodiment of the dispenser  40 , shows the first segment  42  and part of the second segment  44  including the second segment rear end  54 . The first segment  42  includes a closed first segment rear end  50 , a tubular first segment body  58 , and an externally threaded open first segment front end  52 . A sealed first reservoir  60  is disposed within the first segment body  58  and comprises a tubular first reservoir body  62 , a frangible first reservoir front end surface  64  projecting forward of the first segment front end  52 , and a longitudinally compressible first reservoir crumple zone  66 . A first rupturing member  68  is stabilized within the first reservoir  60  and comprises a bifurcated first thrusting member  70 , a first cutting edge  72 , and a first spreading member  74  attached thereto and disposed proximate the first reservoir front end surface  64 . The first thrusting member  70  may be formed integrally with the first reservoir body  62  or it may be braced within the first reservoir  60 , so long as it resists rearward displacement relative to the first segment  42  when the first reservoir body  62  is disposed against the closed first segment rear end  50 .  
         [0080]    With continued reference to FIG. 3, the second segment  44  comprises a tubular second segment body  76  and an internally threaded open second segment rear end  54 . A second reservoir  78  is disposed within the second segment body  76  and comprises a tubular second reservoir body  80  and a frangible second reservoir rear end surface  82 . The second reservoir  78  is supported within the second segment  44  so as to resist forward displacement relative to the second segment  44 . The second segment rear end  54  and the first segment front end  52  are adapted for mutual threaded engagement.  
         [0081]    [0081]FIG. 4, a side view of the embodiment of FIG. 3, shows the first segment front end  52  partially screwed into the second segment rear end  54 , the first cutting edge  72  and the first reservoir front end surface  64  being proximate the second reservoir rear end surface  82 .  
         [0082]    [0082]FIG. 5, a side view of the embodiment of FIG. 3, shows the first segment front end  52  completely screwed into the second segment rear end  54 . The first reservoir front end surface  64  has interfered longitudinally with the second reservoir rear end surface  82 . The first reservoir crumple zone  66  has been compressed, allowing the first reservoir front end surface  64  to be displaced rearwardly onto the first cutting edge  72 . The first cutting edge  72  has pierced the first reservoir front end surface  64  and the second reservoir rear end surface  82 , both of which are thereafter held open by cooperation of the first cutting edge  72 , the first thrusting member  70 , and the first spreading member  74 . The held-open first reservoir front end surface  64  and second reservoir rear end surface  82  and the bifurcated first thrusting member  70  establish fluid communication between the first reservoir  60  and the second reservoir  78 .  
         [0083]    [0083]FIG. 6, a side view of the embodiment of FIG. 3, shows the second segment  44  and the third segment  46  and a part of the first segment  42  including the first segment front end  52  screwed into the second segment rear end  54 . The second segment  44  comprises an open, internally threaded second segment front end  56 . The second reservoir  78  comprises a frangible second reservoir front end surface  84  disposed within the second segment body  76  and proximate the second segment front end  56 .  
         [0084]    With continued reference to FIG. 6, the third segment  46  comprises an externally threaded tubular third segment body  86  to which are attached a rearward-projecting second rupturing member  88  and a forward-projecting applicator  48 . The second rupturing member  88  comprises a rearward-projecting bifurcated second thrusting member  90  affixed to the third segment  46  and a second cutting edge  92  and a second spreading member  94  formed distally thereon. The applicator  48  is formed of a porous, fibrous, or ducted material capable of conducting and dispensing a liquid. The third segment body  86  and the second segment front end  56  are adapted for mutual threaded engagement. It will be appreciated that after the third segment  46  is fully screwed into the second segment front end  56 , the second cutting edge  92  has pierced the second reservoir front end surface  84 , which is thereafter held open by cooperation of the second cutting edge  92 , the second thrusting member  90 , and the second spreading member  94 . The held-open second reservoir front end surface  84  and the bifurcated second thrusting member  90  establish fluid communication between the second reservoir  78  and the applicator  48 .  
         [0085]    The first segment  42  and second segment  44  may comprise a polymeric structure stiff enough to be manually grasped and twisted without buckling or cracking; strong enough and hard enough to bear the longitudinal force of propelling a pointed cutting edge through a frangible membrane; and hard enough to generate this force from torque by threaded engagement. Ideally, the first segment front end  52 , second segment rear end  54 , second segment front end  56 , and third segment  46  should be plastic enough and smooth enough to confine liquid contents under light pressure without any need for additional washers or o-rings.  
         [0086]    The first reservoir body  62  and the second reservoir body  80  may comprise a polymeric structure stiff enough to resist longitudinal compression except in the first reservoir crumple zone  66 . The first reservoir front end surface  64 , second reservoir rear end surface  82 , and second reservoir front end surface  84  may comprise a polymeric structure frangible enough to be pierced by a pointed cutting edge. Low or medium density polyethylene, polypropylene, and other common container materials are contemplated. A metallic, glass, ceramic, or composite reservoir material may in some cases be preferred for opacity or impermeability.  
         [0087]    The first thrusting member  70 , first cutting edge  72 , and first spreading member  74  may comprise a polymeric structure having sufficient stiffness and hardness to pierce a frangible membrane. High density polyethylene, polycarbonate, polystyrene, and polyvinyl chloride are contemplated, although metal, glass, ceramic, or wood may be preferred.  
         [0088]    [0088]FIG. 7, a side view of another preferred embodiment of the hair colorant dispenser  40  in accordance with the present invention, shows the first segment  42  and part of the second segment  44  including the second segment rear end  54 . Also shown are the first segment  42 , a closed first segment rear end  50 , a tubular first segment body  58 , an externally threaded open first segment front end  52 , a sealed first reservoir  60  disposed within the first segment body  58  and comprising a tubular first reservoir body  62 , a frangible first reservoir front end surface  64  projecting forward of the first segment front end  52 , and a longitudinally compressible first reservoir crumple zone  66 ; a first rupturing member  68  stabilized within the first reservoir and comprising a bifurcated first thrusting member  70  and a first cutting edge  72  attached thereto and disposed proximate the first reservoir front end surface  64 .  
         [0089]    With continued reference to FIG. 7, also shown is the second segment  44  comprising a tubular second segment body  76  and an internally threaded open second segment rear end  54 ; a second reservoir  78  disposed within the second segment body  76  and comprising a tubular second reservoir body  80  and a frangible second reservoir rear end surface  82  and being supported within the second segment  44  so as to resist forward displacement relative to the second segment  44 ; the second segment rear end  54  and the first segment front end  52  being adapted for mutual threaded engagement. An elastic ring seal  96  is disposed within the second segment body  76  adjacent and to the rear of the second reservoir rear end surface  82 . The ring seal  96  may be formed of rubber, silicone, or any suitable washer-forming or gasket-forming material.  
         [0090]    [0090]FIG. 8, a side view of the embodiment of FIG. 7, shows the first segment front end  52 , the structures thereof being already identified with reference to FIG. 7, partially screwed into the second segment rear end  54 , the first cutting edge  72  being advanced into and displacing the first reservoir front end surface  64  and the second reservoir rear end surface  82 , the seal  96  being trapped in a space defined by the first reservoir body  62 , the first segment front end  52 , the second segment rear end  54 , and the second reservoir front end surface  84 .  
         [0091]    [0091]FIG. 9, a side view of the embodiment of FIG. 7, shows the first segment front end  52  completely screwed into the second segment rear end  54 . The first cutting edge  72  has pierced the first reservoir front end surface  64  and the second reservoir rear end surface  82 , both of which are held open by cooperation of the first cutting edge  72 , the first thrusting member  70 , and the first spreading member  74 . The held-open first reservoir front end surface  64  and second reservoir rear end surface  82  and the bifurcated first thrusting member  70  establish fluid communication between the first reservoir  60  and the second reservoir  78 . The seal  96  helps to prevent leakage of liquid between the first segment front end  52  and second segment rear end  54 . The sealing engagement of the third segment  46  to the second segment front end  56  may be enhanced in a similar manner.  
         [0092]    This exemplary embodiment transmits longitudinal force to a single cutting edge to reliably rupture the first reservoir front end surface  64  and the second reservoir rear end surface  82 , the resistance being supplied by the second reservoir  78  and ultimately the second segment  44 .  
         [0093]    [0093]FIG. 10 shows a side view of another exemplary embodiment of the hair colorant dispenser  40  in accordance with the present invention comprising a first segment  42  including a closed first segment rear end  50 , a tubular first segment body  58 , and an externally threaded open first segment front end  52 . A sealed first reservoir  60  is disposed within the first segment body  58  and comprises a tubular first reservoir body  62 , a frangible first reservoir front end surface  64 , and an open-ended tubular lining  98  projecting forward thereof. A double-ended, coupling rupturing member  100  is stabilized within the lining  98  and projects therefrom to a distance forward of the first segment front end  52 . The double-ended, coupling rupturing member  100  comprises a tubular connector  102 , a front punch  104  including a cruciform front cutting edge  106  and a cruciform front stop  108 , and a rear punch  110  including a cruciform rear cutting edge  112  and a cruciform rear stop  114 .  
         [0094]    [0094]FIG. 11, a side view of the embodiment of FIG. 10, shows the second segment  44  comprising a tubular second segment body  76 , an internally threaded open second segment rear end  54 , and an internally threaded open second segment front end  56 . A second reservoir  78  is disposed within the second segment body  76  and comprises a tubular second reservoir body  80 , a frangible second reservoir rear end surface  82 , and a frangible second reservoir front end surface  84 . The second reservoir  78  is supported within the second segment  44  so as to resist longitudinal displacement relative to the second segment  44 . The second segment rear end  54  and the first segment front end  52  are adapted for mutual threaded engagement. An elastic ring rear seal  116  is disposed within the second segment body  76  adjacent and to the rear of the second reservoir rear end surface  82 . An elastic ring front seal  118  is disposed within the second segment body  76  adjacent and to the rear of the second reservoir front end surface  84 . Alternatively, the second reservoir  78  may be modified to form both forward-projecting and rearward-projecting linings comparable to the lining  98  formed on the first reservoir  60 ; the linings may be formed of a moderately plastic material capable of sealing the engagement between the first segment  42  and the second segment  44  or between the second segment  44  and the third segment  46 .  
         [0095]    [0095]FIG. 12, a side view of the embodiment of FIG. 10, shows the first segment front end  52  partially approximated to the second segment rear end  54 . The connector  102  is shown stabilized within the lining  98  and partly engaged with the rear seal  116 . The rear punch  110  is proximate the first reservoir front end surface  64 . The front punch  104  is proximate the second reservoir rear end surface  82 .  
         [0096]    [0096]FIG. 13, a side view of the embodiment of FIG. 10, shows the first segment front end  52  completely screwed into the second segment rear end  54 . The cruciform rear punch  110  has pierced the first reservoir front end surface  64 . The cruciform rear stop  114  has interfered with the first reservoir front end surface  64  and is thereby urged forward. The cruciform front punch  104  has pierced the second reservoir rear end surface  82 . The cruciform front stop  108  has interfered with the second reservoir rear end surface  82  and is thereby urged rearward. The connector  102  assures that the frontward and rearward force are balanced by piercing both the first reservoir front end surface  64  and the second reservoir rear end surface  82 , rather than advancing excessively beyond one and piercing the other only partially or not at all. The front punch  104 , front stop  108 , rear punch  110 , rear stop  114 , and connector  102  cooperate to hold open the ruptured first reservoir front end surface  64  and second reservoir rear end surface  82  and to establish fluid communication between the first reservoir  60  and the second reservoir  78 .  
         [0097]    [0097]FIG. 14, a side view of the embodiment of FIG. 10, shows part of the second segment  44  and the entire third segment  46 , the third segment  46  comprising an externally threaded tubular third segment body  86  to which are attached a rearward-projecting single-ended rupturing member  120  and a forward-projecting applicator  48 . The single-ended rupturing member  120  comprises a rearward-projecting third punch  122  and third stop  124  formed distally thereon. The applicator  48  is formed of a porous, fibrous, or ducted material capable of conducting and dispensing a liquid. The third segment body  86  and the second segment front end  56  are adapted for mutual threaded engagement. It will be appreciated that when the third segment  46  is fully screwed into the second segment front end  56 , the single-ended rupturing member  120  will have engaged the front seal  118 , the third punch  122  will have pierced the second reservoir front end surface  84 , and the third stop  124  will thereafter cooperate with the third punch  122  to hold open the second reservoir front end surface  84 , thereby establishing fluid communication between the second reservoir  78  and the applicator  48  as indicated by the arrow in the cut-out view.  
         [0098]    This exemplary embodiment balances the forces exerted on the front punch  104  and the rear punch  110  of the double-ended rupturing member, thereby assuring reliable rupture of two reservoir ends surfaces.  
         [0099]    With a single twisting operation, all described embodiments of the present invention provide for reliable rupture of all three frangible reservoir end surfaces in order to mix the contents of the first reservoir  60  and the second reservoir  78  and to dispense the mixed contents.  
         [0100]    Optionally, the first segment body  58  and the second segment body  76  may be squeezed to facilitate mixing (liquid may be forced back and forth between the first reservoir  60  and the second reservoir  78 ). Optionally, gravity and a small volume of air or other gas may be used to mix the contents by inverting the dispenser  40  several times. Optionally, the contents may quickly be delivered to the applicator  48  by squeezing one or both of the first segment  42  and the second segment  44 .  
         [0101]    Optionally, a cap may be provided to protect the applicator  48 . Optionally, the applicator  48  may be designed to be substantially shorter than the rupturing member and the third segment  46  may be externally threaded so as to engage the second segment front end  56  with the applicator  48  facing the second segment front end  56 . With the second segment  44  and the third segment  46  so joined, the applicator  48  (which may be soft and easily damaged or soiled) may be protected from external impacts and, at the same time, the rupturing member is kept completely away from the second reservoir front end until the time of use. For dispensing contents, the third segment  46  is unscrewed, reversed, and screwed back onto the second segment  44 .  
         [0102]    Optionally, the first segment rear end  50  may be externally threaded to engage the second segment rear end  54 . Thus, the dispenser  40  may be shipped with the first rupturing member  68  (or the front punch  104 , as the case may be) positioned safely away from the second reservoir rear end surface  82 . If this is done, a cap should be provided to protect the first reservoir front end surface  64  from impacts and to prevent ejection of the first reservoir  60  (or of the double-ended rupturing member, as the case may be).  
         [0103]    It is to be understood that internal threading and external threading may be interchanged, that a lining may in some cases be interchanged with a ring seal, and that both the lining and the ring seal can be omitted if the segments can be made to sealingly engage without a lining or seal.  
         [0104]    It is to be understood that the double-ended rupturing member could be broken into equal or unequal parts and the parts apportioned between the first segment  42  and the second segment  44 .  
         [0105]    It is to be understood that the first rupturing member  68  could be transferred from the first reservoir  60  to the second reservoir  78  and inverted.  
         [0106]    It is to be understood that the second rupturing member  88  or the third punch  122  (each having been disclosed as projecting rearwardly from the third segment  46 ) may be omitted if an additional rupturing member were to be so disposed within the second reservoir  78  that the second reservoir front end surface  84  were rupturable upon compression of the second reservoir  78  when the third segment  46  is screwed into the second segment front end  56  surface. The second reservoir  78  could, for example, have a crumple zone such that the second reservoir front end surface  84  and the second reservoir rear end surface  82  are pierced by opposite ends of a single rupturing member disposed within the second reservoir  78 . The first reservoir  60  could in such a case be supplied without a crumple zone, so that the first reservoir front end surface  64  is ultimately pierced by the same cutting edge or punch that pierces the second reservoir rear end surface  82 . Indeed, a double-ended rupturing member of the type described with reference to FIG. 10 could be provided with an elongated connector  102  and could be disposed within the second reservoir  78  to rupture three end surfaces. In such an arrangement, the second reservoir  78  should have sufficient freedom of longitudinal movement and sufficient longitudinal compressibility to allow for the balancing of forces so that the rupturing member will adequately pierce all three membranes. This arranagement would be advantageous in that threre would be no externally projecting cutting edges nor any externally projecting double-ended rupturing member to be dislodged or damaged by mishandling or to inflict injury on persons.  
         [0107]    While the foregoing detailed description has described several embodiments of a hair colorant dispenser  40  in accordance with the present invention, it is to be understood that the above description is illustrative only and not limiting of the disclosed invention. Indeed, it will be appreciated that the embodiments discussed above and the virtually infinite embodiments that are not mentioned could easily be within the scope and spirit of the present invention. Thus, the present invention is to be limited only by the claims as set forth below.