Abstract:
A gravity discharge device for liquids, especially concentrated liquid detergents, comprises a valve guide system whose surface area optimizes liquid flow. The discharge is especially useful with concentrated (“2×”) liquid detergents, whose viscosities tend to unacceptably slow their flow rate from home-use containers, especially when the containers progressively empty after multiple uses.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation-in-part of U.S. applications Ser. Nos. 11/728,469; 11/728,468; and 11/728,363, all concurrently filed Mar. 26, 2007, the disclosures of which are incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     This invention relates to improvements in discharge devices, such as diaphragm taps, designed for delivering viscous liquids such as concentrated laundry detergents. 
     BACKGROUND OF THE INVENTION 
     The eventual replacement of today&#39;s so-called “1×” liquid laundry detergents and liquid fabric softeners with modern, more concentrated “2×” formulations is of considerable commercial importance. Doubling the concentration of active ingredients in such compositions allows usage levels to be halved. Thus, for the same number of product usages, only half the volume of product need be supplied to the consumer. This results in considerable savings in packaging materials and shipping costs, as well as simplifying transportation and storage of the product by the consumer. Importantly, the overall carbon footprint of the product is reduced. Of course, the change-over from (1×) formulations to (2×) formulations is not without its problems. Changing the habits and practices of consumers can be remarkably challenging, especially since most consumers are quite satisfied with their current (1×) products. Accordingly, consumers must be educated regarding the benefits of the (2×) formulations and are quick to notice and assert their displeasure concerning any perceived problems associated with the change-over. On the other hand, consumers do expect some differences in product attributes that signal they are using the new (2×) version, 
     One expected visual and tactile signal for any concentrated liquid formulation is that it be more viscous that its less concentrated version. This expectation is easily met with liquid laundry detergents, due at least in part to the phase properties of the detersive surfactants used therein. For example, conventional (1×) liquid laundry detergents typically have viscosities in the range of 250 to 300 cps, whereas the counterpart (2×) formulations may have viscosities in the range of about 350 to about 700 cps, typically about 350 to about 500 cps. 
     One quite successful innovation in the marketing of (1×) formulations has been the introduction of large, economy-size containers from which liquid product is dispensed by means of a tap, rather than by pouring. Of course, the introduction of the (2×) formulation does allow the size of the container to be reduced, but tap dispensing is still desirable on the larger product sizes. 
     Unfortunately, however, it has now been unexpectedly discovered that the higher viscosities of (2×) formulations can result in unacceptably slow product flow through the tap dispensers that are commercially available for (1×) formulations. Moreover, to change the overall design and size of the currently-available taps would require quite expensive re-tooling. This presents a problem to the manufacturer: to meet consumer expectations for a (2×) product that is more viscous, but has an acceptable flow rate through a dispenser tap that can be produced economically. The present invention addresses this flow problem in a cost-effective manner, as will be seen from the following disclosure. 
     BACKGROUND ART 
     U.S. Pat. No. 4,452,425, to Anthony J. Lucking, issued Jun. 5, 1984, describes a plastic diaphragm tap comprising a tubular body open at one end and closed at the other end by a flexible resilient diaphragm. The diaphragm is connected to a shaft comprising a valve element, said valve element being arranged to close a valve seat at the open end of the tap. Finger pressure on the diaphragm displaces the valve element and opens the tap. Conversely, release of said pressure allows the normal resilience of the diaphragm to re-seat the valve element against the valve seat, thereby closing the tap. 
     The Lucking tap is disclosed for delivering liquids, such as wine or milk, from a storage container. The configurations of the valve seat and valve element in this tap are taught to cooperate so that the valve element self-centers against the valve seat to close the tap in dripless fashion. Reference can be made to U.S. Pat. No. 4,452,425 for details of the manufacture and use of said Diaphragm Tap. 
     Despite the teachings of U.S. Pat. No. 4,452,425, it has been the experience of the Applicants herein that diaphragm taps cannot be completely relied on to self-center and to satisfactorily close in dripless fashion under all circumstances. As will be appreciated, drippage of liquid laundry products from the tap would be unacceptable to the user of such products. It has also been discovered that, during use, the valve can skew off-center, with the result that liquid product can sometimes exit predominantly towards the rear of the tap, whereas at other times it can exit towards the front. This can lead to product spillage and a poor consumer experience. 
     In order to ensure proper centering of the valve, which is essential to ensure dripless closure and smooth, repeatable product flow from dose-to-dose, diaphragm taps can be fitted with a valve guide. The valve guide centrally positions the shaft that communicates between the diaphragm and the valve element in the tubular body. The valve guide is typically affixed to the internal walls of the tubular body by means of substantially horizontal support ribs, said ribs fixedly positioning the valve guide substantially concentrically with the midline axis of the tubular body. The valve guide comprises a throughhole through which the shaft slidingly passes as the valve is opened and closed by the respective application and release of pressure on the diaphragm. 
     Commercial experience with the delivery of conventional (1×) liquid laundry detergents using diaphragm taps that comprise valve guides has been excellent. As noted above, however, it has now been discovered that the flow rate of concentrated (2×) liquid detergents through such taps is too slow for some consumers. This is because the diaphragm tap is gravity-fed. Accordingly, as the product container empties with successive uses and the hydrostatic pressure decreases correspondingly, the flow rate is reduced. 
     Having discovered the flow rate problem with diaphragm taps used to deliver viscous liquids, it has now also been discovered that a more consumer acceptable flow rate for (2×) products can be achieved by modifying the tap in the manner disclosed herein. Surprisingly, the tap modified according to at least a preferred embodiment of the invention also provides consumer-acceptable flow rates across a range of viscosities, and even for conventional (1×) liquid products. This is a considerable commercial advantage, since the manufacturer of such products, e.g., liquid fabric enhancers such as detergents and softeners, can use the same tap interchangeably with both (1×) and (2×) liquid products. 
     SUMMARY OF THE INVENTION 
     In one aspect, the present invention comprises a discharge device comprising a body  100  having a hollow interior  200 , said body comprising a liquid inlet portion; a liquid outlet portion comprising a first end and a second end, wherein said first end comprises a button, wherein said liquid outlet has an orifice comprising an orifice surface area comprising a stem and valve system comprising a rib and a valve guide comprising a valve system surface area wherein said stem passes through said valve guide, and wherein, 
     said valve system surface area and said orifice surface area have a ratio of less than about 35%, preferably less than about 30%, or 20% or even 10%. 
     In one embodiment, the present invention encompasses a discharge device (i.e., “tap”) having a liquid outlet with a hollow interior. The valve system is located at the junction of the liquid inlet and the liquid outlet. The valve guide system has a valve guide and a first rib. The valve guide system has a valve guide having a valve guide width. The valve guide width is preferably less than about 1.15 mm. The first rib has a first rib width having a first rib width which is preferably less than about 2.5 mm. 
     In another embodiment, the invention encompasses a discharge device comprising a body having a hollow interior; a liquid inlet comprising a liquid inlet surface area, a liquid outlet wherein said liquid outlet has a hollow interior comprising a stem and a valve guide comprising a top, a bottom, and a valve guide surface area, said stem passes through said valve guide, and characterized in that said bottom of said valve guide is above (preferably, at least about 3 mm) said liquid inlet. 
     The invention also encompasses an article of manufacture, comprising a container comprising a reservoir for storing a liquid composition, especially a liquid (“2×”) detergent having a viscosity above about 350 cps, and an improved diaphragm tap, as disclosed above and as described more fully hereinafter. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of an embodiment of the discharge device of the present invention; 
         FIG. 2A  is a cross-section view along line  2 A- 2 A of the discharge device of  FIG. 1 . 
         FIG. 2B  is a cross-section view along line  2 B- 2 B of the discharge device of  FIG. 1  while the button is pressed. 
         FIG. 2C  is a cross-section view along line  2 A- 2 A of an alternative embodiment of the discharge device. 
         FIG. 3  is a front view of the discharge device. 
         FIG. 4  is a cross-section view along line  4 - 4  of the discharge device of  FIG. 3 . 
         FIG. 5  is a front view of an alternative embodiment of the discharge device. 
         FIG. 6  is a cross-section view along line  6 - 6  of the alternative embodiment of the discharge device of  FIG. 5 . 
         FIG. 7  is a front view of an alternative embodiment of the discharge device. 
         FIG. 8  is a cross-section view along line  8 - 8  of the alternative embodiment of the discharge device of  FIG. 7 . 
         FIG. 9  is a front view of an alternative embodiment of the discharge device. 
         FIG. 10A  is a cross-section view along line  10 A- 10 A of the alternative embodiment of the discharge device of  FIG. 9 . 
         FIG. 10B  is a front view of an alternative embodiment of the discharge device. 
         FIG. 10C  is the cross-section view along line  10 C- 10 C of the discharge device of  10 B. 
         FIG. 11  is a front view of an alternative embodiment of the discharge device. 
         FIG. 12  is a perspective view of an alternative embodiment of the discharge device. 
         FIG. 13  is a graph showing fluid flow through dispenser taps. 
     
    
    
     The figures herein are not necessarily drawn to scale. 
     DETAILED DESCRIPTION OF THE INVENTION 
     Section A will provide terms which will assist the reader in best understanding the features of the invention, but is not intended to introduce limitations in the terms inconsistent with the context in which they are used in this specification. These definitions are not intended to be limiting. 
     Section B will discuss the discharge device of the present invention. Section C will discuss examples of the present invention. 
     A. TERMS 
     As used herein, the “orifice” is measured as the cross-section of the smallest perimeter of the liquid outlet. Of course, for a cylindrical outlet, the perimeter has a constant value. 
     The viscosity of the liquid compositions can be measured at 21.1° C. using a Brookfield LV DV II instrument conducted according to the manufacturer&#39;s instructions with the #31 spindle run at 60 rpm. This approximates the shear rate, ca. 20 l/sec, of the product being dispensed from the container. 
     All percentages herein are by weight, unless otherwise specified. 
     The dimensions and values disclosed herein are not to be understood as being strictly limited to the exact numerical values recited. Instead, unless otherwise specified, each such dimension is intended to mean both the recited value and a functionally equivalent range surrounding that value. For example, a dimension disclosed as “40 mm” is intended to mean “about 40 mm”. 
     B. PACKAGE OF THE PRESENT INVENTION 
     I. Discharge Device 
     Referring to  FIG. 1 , a discharge device  20  is shown which is designed to dispense a liquid composition  1  from container  22 . In this embodiment the container comprises filler opening  2  that can be repeatedly sealed and opened, e.g., with a screw cap  3 . In-use, the screw cap is loosened or removed to allow air to enter the container. Indicia, such as arrow  4  or other instructions can be provided on the container as a reminder to the user to loosen the cap during use. 
     Referring to  FIG. 2A ,  FIG. 2B  and  FIG. 2C , the present invention provides a discharge device  20  for dispensing liquids, especially viscous liquids from a container  22  (See  FIG. 1 ). In the embodiment shown, the body  100  of the discharge device  20  has a liquid inlet portion  24  and a tubular liquid outlet portion  26 . The tubular liquid outlet portion  26  has an orifice  29 , a first (proximal) end  30 , and a second (distal) end  32  opposite to the first end  30 . The orifice  29  of the tubular liquid outlet portion  26  opens and closes by a valve system  35  (see  FIGS. 2A-10B ) comprising a stem  36  which passes through the throughhole  6  (see  FIG. 3 ) in valve guide  34 . (see  FIG. 3 ) In this embodiment, the stem  36  is fixedly inserted into the downwardly accepting socket  5  of button  42 , which, in this embodiment is a domed diaphragm, as discussed more fully hereinafter. 
     Generally, referring again to  FIG. 2A  and  FIG. 2C , when the button (diaphragm)  42  is unpressed, the stem  36 , terminating in a frusto-conical valve element  21 , which can be seated in the sidewalls  40  of the tubular liquid outlet portion  26  by compressing against the sidewall  40  so that no liquid can flow from the container  22  (See  FIG. 1 ) with which the discharge device  20  is used. Referring to  FIG. 2B , when pressure is applied to the button  42 , the stem  36  moves downwardly along the midline axis  44  to unseat the valve element  21  from the outlet orifice  29  which may have conical seating  50  constituted by the walls  40 . As a result, liquid flows along a liquid flow passageway around the stem  36  and valve guide  34  and rib(s)  60  and through the valve system  35  (see  FIGS. 3-10B ). In a preferred embodiment shown in  FIG. 2A , the sidewall  40  has a terminal edge  7 , which is preferably beveled in order to sealingly seat the frusto-conical valve element  21  when the valve is in the closed position. 
     Referring to  FIG. 1 , using a discharge device  20  of this type avoids the problems caused by a number of soap containers, bleach containers, conditioner containers, and other containers around the laundry area. It also eliminates the need for lifting a gallon container or other heavy item for handling this matter by being able to discharge the liquid from any surface. Moreover, it also reduces the amount of time needed to discharge the liquid and simplifies the application of the right amount of the product at the right time, thereby reducing waste. For those without the strength to lift a heavy container, this discharge device  20  and container  22  keep the washing liquid readily available. 
     The discharge device  20  and container  22  may be formed from any suitable material such as high-density polyethylene, low-density polyethylene, polypropylene or linear low-density polyethylene. 
     A. LIQUID INLET 
     Referring to  FIG. 2A , generally, the liquid inlet  24  is provided to allow liquid to flow therethough from the container  22  (see  FIG. 1 ) and into and through liquid outlet portion  26  and out of orifice  29 . 
     The attachment  62  can be formed with screw threads  38  (See  FIG. 2A ) to allow joining of the discharge device  20  to a container  22  (see  FIG. 1 ) at the container&#39;s liquid egress port  101  ( FIG. 2A ). It will be appreciated that the discharge device  20  can be attached to a container  22  in other ways, but a connection which is not destroyed on removal of the discharge device  20  after emptying the container  22  may be preferred because it makes the discharge device  20  reusable. Other ways attachment  62  can be used to attach the discharge device  20  and the container  22  are by pressure seal, an adhesive seal, a locking closure, a screw-type closure, a snap-fit closure, a heat seal, an ultrasonic seal, and/or a plug-seal and may optionally be air-tight and/or water-tight as desired for example, to prevent oxidation of the pourable product, absorption of moisture from the air, and/or water damage to the pourable product. 
     B. LIQUID OUTLET 
     Referring to  FIG. 2B , the liquid outlet portion  26  of the device  20  is formed to allow liquid to flow therethrough from the container  22  and to provide a seal at the second end  32  of the liquid outlet  26  to prevent liquid from leaking. As stated above, the liquid outlet  26  comprises an orifice  29 , which is characterized by its cross-sectional area  28 , a first end  30 , and a second end  32  opposite to the first end  30 . The liquid outlet portion  26  contains a valve guide  34  and a stem  36  which passes through the valve guide  34 . 
     i. Valve System 
     Referring to  FIG. 3-FIG .  10 B, the valve system  35  comprises the valve guide  34  and the rib(s)  60 . Both are described separately in detail below. The valve system  35  can be located anywhere along the liquid outlet portion  26 . As seen in  FIG. 2A  and  FIG. 2B , the valve system  35  can be in the path of the liquid flow passageway. In other words, the liquid is in contact with the valve system  35  when the button  42  is depressed to release the liquid from the container  22 . 
     Alternatively, as seen in  FIG. 2C , the valve guide  34  of valve system  35  can be constructed to not be in the path of the liquid flow passageway while the liquid is flowing from the liquid inlet  24  through the liquid outlet portion  26 . In this embodiment, the bottom  9  of the valve guide  34  is positioned at or above the junction  8  of the liquid inlet  24  and the outlet portion  26 . In other words, the liquid is not in substantial contact with the valve guide when the button is depressed to release the liquid from the container  22 . In this embodiment, the valve system  35  is used as a guide for the stem  36  to provide stability, but allows for faster liquid flow because there is not substantial liquid contact with the ribs and valve guide. However, it is to be understood that this is not a preferred arrangement for use herein, since downward pressure during operation of the device can cause the button to undesirably impinge on the valve guide/rib assembly. 
     a. Valve Guide 
     Referring to  FIG. 2A-FIG .  10 C, valve guide  34  is secured to the interior surface  19  of sidewall  40  of the liquid outlet  26  by ribs  60 . The valve guide  34  stabilizes the liquid flow profile and provides a maximum flow rate. Referring to  FIG. 3-FIG .  10 C, the higher flow rate is achieved by decreasing the surface area of the elements of the valve system that limit flow passage, which is the valve system  35 . To increase the flow through the valve system  35 , the cross sectional area of the valve system  35  is reduced while still maintaining the valve system  35 &#39;s structural performance. Generally, reducing the cross sectional area also decreases the width  59  of the valve guide  34  and the width  64  of the ribs  60 . Accordingly, reducing the width which is perpendicular to the flow of the liquid of the valve system  35  decreases drag on fluid passing through the liquid outlet  26 . Stated otherwise, the surface areas of the top side  13  (side facing the proximal end of the device) of the ribs and top side  11  of the valve guide are minimized, compared with current commercial practice, as discussed more fully hereinafter. 
     In addition, the valve guide  34  geometry can be changed to increase flow. Referring to  FIG. 10B , the width  59  of the valve guide  34  is ovalized  61 . The width  59  of the valve guide  34  is preferably at least less than about 1.15 mm. 
     b. Ribs 
     Referring to  FIGS. 3-10C , the ribs  60  connect the valve guide  34  to the interior surface  19  of the sidewall  40  of the liquid outlet  26 . The ribs  60  can be part of the sidewall (i.e., “walls”)  40  by molding or may be inserted by being bonded or spin welded. The ribs communicate between the interior surface  19  of the sidewall and the valve guide  34 . The width  64  of the ribs  60  is preferably at least less than about 2.5 mms. In this invention, the ribs  60  are reduced in width to decrease drag on fluid passing through (see  FIG. 3 ,  5 ,  7 ,  9 ,  10 B) the liquid outlet  26 . 
     Referring to  FIG. 4 ,  FIG. 6 ,  FIG. 8 , and  FIG. 10 , in addition, the rib  60  geometry can be changed to increase flow and reduce surface contact of the liquid with the valve system  35 . Referring to  FIG. 4  and  FIG. 8 , the rib  60  may be angled upward where the valve guide  34  is in a plane above the rib  60 . Referring to  FIG. 10A , in another embodiment, the rib  60  may be angled downward or inverted where the valve guide  34  is in a plane below the rib  60 . 
     ii. Stem 
     Referring to  FIG. 2A  and  FIG. 2B , the stem  36  forms a connection between the button  42  and the valve element  21  at liquid outlet  26 . The stem  36  comprises a first end  54  and a second end  56  opposite to the first end  54 . The first end  54  is adjacent to the button  42  and protrudes downwardly from the button  42 . The stem  36  can have its first end  54  shown seated in the button  42  and the second end  56  on conical (beveled) seating  50 . 
     The second end  56  of the stem  36  comprises the valve element  21  that seals the outlet  52  of the liquid outlet portion  26  at orifice  29  and is the sealing for controlling the normal or repetitive opening and re-sealing of the discharge device  20 . The second end  56  of the stem  36  comprises valve element  21  which can be conical or frusto-conical, and can be arranged to seat on the edge of orifice  29 , said orifice comprising a correspondingly tapered  50  edge  7  so as to close the liquid outlet portion  26 . The outer edge of the external surface of the valve element is flush with the adjacent part of the second (distal) end  32  of the liquid outlet  26  when the discharge device  20  is closed so that there is virtually no space within which liquid pass by virtue of its surface tension. A sealing bead  58  can optionally surround the stem  36  and/or valve element  21  to ensure adequate contact pressure on the liquid outlet  26  at the terminal edge  7  of orifice  28 . The stem  36  passes through a valve guide  34 . Typically, the stem  36  (including its valve element) extends the length of the liquid outlet portion  26 . The length of the stem  36  can be any length which fits within the liquid outlet portion. In one alternative embodiment, the length of the stem  36  (including valve element  21 ) can be about 33 mms. 
     iii. Button 
     Referring to  FIG. 2A  and  FIG. 2B , when the button  42  is depressed, liquid is released from the liquid outlet portion  26  through outlet  52 . Specifically, when the button  42  is depressed, the button  42  acts on the stem  36  movable along axis  44  so that orifice  29  of outlet portion  26  is opened. The stem  36  is supported by the valve guide  34  and rib(s)  60 . When the valve is opened, liquid is allowed to flow from the container  22  (see  FIG. 1 ) through the liquid inlet  24  past the stem  36  and valve guide  34  and ribs  60  and out of the orifice  29  of the liquid outlet portion  26 . On release of the button  42 , the stem retracts and outlet portion  26  is closed. 
     The button  42  can have a chamfered socket portion. The stem  36  can have its first end  54  shown seated in the button  42  and the second end  56  including the valve element  21 , on conical seating  50 . The valve element  21  at the second end  56  of the stem  36  seals the outlet of the discharge device  20  and is the sealing for controlling the normal or repetitive opening of the discharge device  20 . 
     In the preferred “diaphragm tap” embodiment shown in the FIGS., the button (i.e., the diaphragm)  42  needs to be resilient, but flexible, so that it is capable of large deformation under manual pressure but subsequently resuming its original shape when the pressure is removed. The button  42  is suitably formed from an elastomeric polymer, for example ethylene vinyl acetate, metallocene polythene or polybutylene terephthlate. 
     iv. Calculation of the Ratio of the Area of the Orifice Compared to the Valve System 
     The ratio of the area  28  of the orifice  29  (which, in a preferred embodiment, corresponds to the cross-sectional area, i.e., the “bore”, of the tubular outlet portion  26 ) compared to the area of the valve system is calculated by measuring the cross-sectional area, perpendicular to the flow of the liquid, of the valve system  35 , i.e., especially the surface area  10  of the top side  11  of the valve guide and the surface area  12  of the top side  13  of the valve guide support ribs and dividing this area by the area  28  of the orifice  29 . 
     To illustrate, the area of the valve system may be calculated as 53.9 square millimeter and the area of the orifice may be calculated as 152.2 square millimeter. Thus, 53.9 divided by 152.2 is the ratio 35.39%. Thus, the discharge device  20  can have ratio of the area  29  of the orifice  28  to the area of the valve system  35  obstructed at less than “about” 35% in the direction of the liquid flow. The software used to determine the area is Sold works 2007.™ 
     II. Container 
     Referring to  FIG. 1 , a discharge device  20  having a container  22  of sufficient size to rest on a shelf and sufficient length so that a dispensing mechanism is held conveniently for use provides the necessary solutions to the problems described above. The container  22  can rest on a shelf above the washer. The container  22  can be of sufficient size to hold a suitable amount of powder or liquid for washing purposes. 
     Preferably, the container  22  has a flat base  23  so that the container  22  can rest easily on a shelf mounted adjacent to the clothes washer. The container  22 , at least partially, overhangs a surface (e.g., shelf, washer, dryer). At the overhanging portion of the container  22 , there is a discharge device  20 . Because the container  22  can be taken down from the shelf, and placed on the washer or other surface to be filled, and the filling aperture in the top of the unit is large, it is easy to refill. 
     The discharge device  20  can fit a cup  63  marked for measuring the amount of liquid, which can be removably held therein. When it is desired to do laundry, it is possible to remove the cup  63  from the discharge device  20 , place the cup beneath the discharge device  20 , press the button  42  to open the outlet  52  of the liquid outlet  26 , fill the cup  63  with the desired amount of liquid, close the outlet  52  ( FIG. 2B ) of the liquid outlet  26  by removing any force placed on the button  42  ( FIG. 2B ), and remove the cup  63  ( FIG. 1 ) from beneath the discharge device  20 . Then the contents of the cup  63  ( FIG. 1 ) can be added to the clothes washer in order to do the laundry. The cup  63  ( FIG. 1 ) may be marked in Braille or levels for the amount of material necessary for each load or size of load of laundry. The cup  63  can also be marked to make it simpler for a person lacking laundry skills to determine how much of each laundry material is to be used. In this fashion, the laundry process may be more simply accomplished. 
     Referring to  FIG. 1 , as stated above, the container  22  is attached to the discharge device  20 . The container material can be any material. It is possible to make the container  22  of a clear plastic so that it can be easily determined when the liquid contained therein is running low, and when the container  22  needs to be refilled. The container  22  may be made of transparent material, translucent material, opaque material or any reasonable combination thereof. The only requirement is that the material be inert to the laundry agent contained therein. Clear bottle materials with which this invention may be used include, but are not limited to: polypropylene (PP), polyethylene (PE), polycarbonate (PC), polyamides (PA) and/or polyethylene terephthalate (PETE), polyvinylchloride (PVC); and polystyrene (PS). 
     The transparent container  22  according to the invention preferably has a transmittance of more than 25%, more preferably more than 30%, more preferably more than 40%, more preferably more than 50% in the visible part of the spectrum (approx. 410-800 nm). Alternatively, absorbency of the container  22  may be measured as less than 0.6 or by having transmittance greater than 25% wherein % transmittance equals: 110Absorbancy×100%. For purposes of the invention, as long as one wavelength in the visible light range has greater than 25% transmittance, it is considered to be transparent/translucent. Enzyme deactivation as a result of UV-damage may occur at very low transmission of UV-B radiation through the container wall. 
     III. Liquid 
     A variety of laundry agents may be used, kept handy for use and dispensed easily. However, it is to be understood that the formulation per se of liquid laundry detergents and liquid fabric enhancing agents such as fabric softeners forms no part of this invention. Liquid detergents typically comprise one or more anionic and nonionic surfactants, various chelators and builder materials, enzymes, bleaches, corrosion inhibitors, perfumes and an aqueous carrier. Liquid fabric softeners typically an aqueous carrier and one or more cationic and/or silicone ingredients that soften, lubricate and provide an anti-static finish on fabrics. The extensive patent literature in this field can be referred to for examples of such compositions. For convenience, the following is a non-limiting example of a concentrated (2×) liquid laundry detergent for use in the manner of the present invention. 
     
       
         
               
             
               
               
               
             
               
               
               
             
           
               
                   
               
               
                 LIQUID LAUNDRY DETERGENT 
               
             
          
           
               
                   
                 INGREDIENT 
                 % BY WEIGHT 
               
               
                   
               
             
          
           
               
                   
                 C12-15 alkyl ethoxylate 4.8 avg EO 
                 11.00 
               
               
                   
                 (commercial paste) 
                   
               
               
                   
                 C12 alkyl benzene sulfonate 
                 3.00 
               
               
                   
                 Sodium C12 alkyl sulfate (commercial paste) 
                 2.50 
               
               
                   
                 C12-14 alkyl ethoxylate .9 EO 
                 0.60 
               
               
                   
                 Citric acid 
                 4.00 
               
               
                   
                 Ethanol 
                 1.5 
               
               
                   
                 PEG 4000 
                 0.08 
               
               
                   
                 1,2 propanediol 
                 3.0 
               
               
                   
                 Monoethanolamine 
                 2.4 
               
               
                   
                 Sodium hydroxide 
                 1.8 
               
               
                   
                 Sodium cumene sulfonate 
                 0.6 
               
               
                   
                 Suds suppressor (DC 1520) 
                 0.01 
               
               
                   
                 Enzymes* 
                 0.10 
               
               
                   
                 Borax 
                 2.8 
               
               
                   
                 Perfume and minors 
                 0.1 
               
               
                   
                 Water 
                 balance 
               
               
                   
               
               
                 *mixture of protease, amylase and cellulase 
               
             
          
         
       
     
     C. EXAMPLES 
     Examples of some embodiments of the invention are set forth hereinafter by way of illustration and are not intended to be in any way limiting of the invention. The examples are not to be construed as limitations of the present invention since many variations thereof are possible without departing from its spirit and scope. In Examples I-VI the cross-sectional area of the bore of the outlet portion is about 152 mm. In all Examples the valve guide is concentric with midline axis  44 . 
     Example I 
     A liquid outlet comprises a hollow interior wherein a valve system is located at the junction of the liquid inlet with the outlet portion. The valve system comprises a valve guide and 2 ribs. The valve guide width is 0.75 mms. Each rib width is 1.55 mms wide. 
     Example II 
     A liquid outlet comprises a hollow interior wherein a valve system is located at the junction of the liquid inlet with the outlet portion. The valve system comprises a valve guide and 3 ribs. The valve guide width is 0.75 mms. Each rib width is 1.55 mms wide. 
     Example III 
     A liquid outlet comprises a hollow interior wherein a valve system is located at the junction of the liquid inlet with the outlet portion. The valve system comprises a valve guide and 1 rib. The valve guide width is 0.75 mms. The rib width is 1.55 mms. 
     Example IV 
     A liquid outlet comprises a hollow interior wherein the bottom of the valve guide of the valve system is located from about 1 mm to about 5 mm above the junction of the liquid inlet with the outlet portion. The valve system comprises a valve guide and 2 ribs. The valve guide is 1.0 mm wide. Each rib tapers and has two widths; the first width is 1.0 mm wide and the second width is 1.2 mm. 
     Example V 
     A discharge device comprises an orifice surface area and a valve system surface area. The orifice surface area is 152.2 square millimeter. The combination of the ribs and the valve guide comprise a valve system surface area. The valve system comprises 2 ribs and a valve guide. Because the valve system surface area is 29.7 square millimeter and the orifice surface area is 152.2 square millimeter, the ratio of the valve system area and the orifice surface area is 19.5%. The stem is 33 mms in length. 
     Example VI 
     A discharge device comprises an orifice surface area and a valve system surface area. The orifice surface area is 152.2 square millimeter. The combination of the ribs and the valve guide comprise a valve system surface area. The valve system comprises 2 ribs and a valve guide. Because the valve system surface area is 32.8 square millimeter and the orifice surface area is 152.2 square millimeter, the ratio of the valve system area and the orifice surface area is 21.6%. The stem is 33 mms in length. 
     As can be seen from the foregoing, the discharge devices herein may be of various types, but are all characterized by a stem that carries a valve element. The stem/valve element combination rides in the bore of the tubular outlet portion of the device, through which the liquid composition flows to exit the device. The valve guide herein functions to substantially center the shaft in the bore, thereby assuring that the valve element will be properly seated when the valve is closed. 
     As noted above, the discharge device operates by gravity. The outlet portion of the device comprises a proximal end, i.e., the end where downward pressure is applied by the user to open the valve, and a distal end, i.e., the end from where the liquid composition is discharged when the valve is opened. It will be appreciated that the proximal end can comprise all manner of elements to which downward hand or finger pressure can be applied in order to open the valve. Various tabs, knobs, pads and the like can be envisioned. In general, such elements may be referred to generically as “buttons.” In one embodiment, such buttons can be spring-loaded so that the valve is automatically re-seated when the downward pressure is released. 
     Furthermore, it will be appreciated that the valve stem can be associated with the activator “button” by any convenient means, including, but not limited to, adhesive bonding, screw threads, sweat fitting, and the like. 
     Likewise, various valve elements for sealing the open distal end of the outlet portion can be envisioned. For example, a simple O-ring closure element would serve the sealing function, as would a washer assembly, and the like. 
       FIG. 13  illustrates the flow problem associated with (2×) liquid detergents using current, commercial discharge devices and the solution afforded by the present invention. 
       FIG. 13  is a graphical representation of the flow of a liquid detergent from a container through the tubular outlet portion (bore) of domed taps. The variation in flow as the container progressively empties is clearly seen for both (1×) and (2×) compositions. In  FIG. 13 , the valve guide comprising an annular ring is held in place by support ribs in the flow path of the liquid detergent flowing through the bore and exiting the tubular outlet portion of the tap. In  FIG. 13 , curve  14  illustrates the flow of a (1×) liquid detergent having a viscosity of about 190 cps using a container comprising a preferred domed tap according to the present invention having a so-called “thin” valve guide with two support ribs and an annular ring, as described hereinafter. Curve  15  illustrates the flow of a (1×) liquid detergent with a current commercial valve guide having four support ribs and an annular ring, whose total top surface area is about twice that of the aforesaid “thin” device herein. Curve  16  illustrates the flow of a (2×) liquid detergent having a viscosity of about 465 cps using the “thin” device of a preferred embodiment of the present invention. Curve  17  shows the flow of the (2×) detergent with the aforesaid current commercial four-rib device. 
     As can be seen, an improvement in flow of about 30% is achieve by the present device as compared with the current commercial device when considering the latter stages of delivery of a (2×) liquid detergent. 
     Having thus described various aspects of the present invention, the following describes and exemplifies preferred, but non-limiting embodiments of the preferred devices herein, comprising diaphragm taps, and their use, but is not intended to limit the scope of the invention. 
     In one aspect, the invention encompasses, an article of manufacture, comprising:
         a) a container comprising a liquid composition releasably housed within said container;   b) a diaphragm tap associated with said container for dispensing said liquid composition, said tap comprising:
           i) a tubular outlet portion having a cross-sectional area (e.g., about 120-200 mm 2 ; preferably about 150 mm 2 ), said tubular outlet portion comprising an open proximal end and an open distal end, said distal end comprising a terminal edge, said tubular outlet portion comprising a sidewall having an inner surface;   ii) an inlet portion integrally formed with the sidewall of said tubular outlet portion at a junction (and, in a non-limiting example, intersecting at about a 90° angle), said inlet portion being associated with said container and providing fluid communication for said composition between said container and said tubular outlet portion;   iii) a valve assembly comprising a flexible resilient domed diaphragm fitted around the open proximal end of said tubular outlet portion and extending upwardly therefrom and comprising a downwardly accepting socket for receiving the first end of a stem, said stem carrying a valve element at its second end, said valve element being frusto-conical and configured to seat at the distal end, preferably on said terminal edge of the distal end, of said outlet portion, said terminal edge preferably being beveled to sealingly match said frusto-conical valve element; and   iv) a valve guide, preferably comprising an annular fitment (preferably, ring), said valve guide having a throughhole through which said stem slidingly passes, said valve guide being substantially centrally affixed with respect to the sidewall in said tubular outlet portion by means of support ribs communicating between said valve guide and the inner surface of the sidewall of said tubular outlet portion. In one aspect of the invention, said tap is characterized by: said valve guide and support ribs, together, having a total top surface area that is less than about 35%, preferably less than about 30%, most preferably less than about 20%, or even 10%, of the cross-sectional area of said tubular outlet portion of said tap. In a highly preferred mode, two support ribs are used to affix the valve guide, which is most preferably an annular ring. (Shown as  24  in  FIG. 9 )   
               

     In another aspect of the invention, said diaphragm tap employed on said article comprises a valve guide, preferably an annular ring, having a top surface area less than about 20.4 mm2, preferably from about 5 mm2 to about 15 mm2, and two support ribs, said two support ribs, together, having a top surface area less than about 21 mm2; and in a highly preferred mode, said tubular outlet portion has a cross-sectional area (i.e., bore) from about 145 mm2 to about 175 mm2. 
     In still another aspect, the invention encompasses the diaphragm taps described above per se for dispensing a liquid composition from a container, said taps being associable with said container via the inlet portion of said taps. 
     Example VII 
     A preferred article herein is as follows: 
     The body of a diaphragm tap is molded from polypropylene plastic. The tap body comprises a substantially cylindrical tubular outlet portion having a sidewall thickness of about 1.4 mm, a cross-sectional bore area of about 152 mm and a length of about 22 mm. The terminal edge of the open distal end of the outlet portion is beveled at an angle of about 15 degrees. The open proximal end of the outlet portion is sealingly capped with a flexible, resilient domed diaphragm, available from Worldwide Dispensers, Lester Prairie, Minn., which extends upwardly about 10 mm from the tubular outlet portion. 
     An inlet portion is integrally formed at about mid-point of said tubular portion and has a rectangular orifice communicating with the bore of the tubular outlet portion for the passage of liquid composition. The rectangular orifice has an area of about 144 mm 2 . 
     A valve guide comprising a ring having a wall thickness of about 0.75 mm and a wall depth of about 1.6 mm is positioned centrally in the bore of the tubular portion by means of two support ribs positioned at 180 degrees from each other on the periphery of the valve guide. The ribs are joined to the inner wall of the tubular outlet portion at an upward angle of about 45° to provide improved support for the valve guide, as compared with horizontal placement of such ribs. In this embodiment, each rib is of the same size and is about 4.4 mm in length, 1.4 mm thick and about 2.0 mm in width, on average (the rib tapers from 2.41 mm to 1.55 mm−avg=2.0) 
     The valve guide comprises a central throughhole having a diameter of about 4.5 mm and has an outside diameter of about 6.0 mm. 
     The operational valve comprises Rigidex™ plastic, has an overall length of about 32 mm and comprises a cylindrical stem whose diameter is about 3.1 mm, which terminates in a frusto-conical valve element at its distal end whose dimensions match the beveled end of the outlet portion. The stem passes through the throughhole of the valve guide and the proximal end of the stem is snugly fitted into a downwardly accepting socket that is molded into the domed diaphragm, and is thereby maintained in a concentric position with respect to the midline of the bore of the outlet portion of the tap. 
     The diaphragm tap is affixed to a container (typical range 3.0-10 liters) comprising a liquid laundry detergent having a typical viscosity range of about 190-500 cps, such that the outlet portion is substantially vertical. In-use, the assembly is judged by a panel of users to provide quite acceptable flow rates for the liquid detergent over repeated usages. 
     While the foregoing illustrates a preferred, two-ribbed version of the tap herein, it is to be understood that the tap herein can comprise a plurality (i.e., 3, 4 or more) of such ribs, as long as the sum of their areas does not cause the total surface area of the guide structure to exceed what is disclosed herein. The taps according to the present invention provide consumer-acceptable flow rates for liquids in the 250-700 cps range of viscosities. 
     All documents cited in the Detailed Description of the Invention are, in relevant part, incorporated herein by reference; the citation of any document is not to be construed as an admission that it is prior art with respect to the present invention. To the extent that any meaning or definition of a term in this document conflicts with any meaning or definition of the same term in a document incorporated by reference, the meaning or definition assigned to that term in this document shall govern. 
     While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.