Patent Publication Number: US-2019166976-A1

Title: Device for separately dispensing materials for use together on human skin

Description:
BACKGROUND 
     Technical Field 
     The present disclosure relates generally to methods and devices for containing and separately dispensing materials for use together on human skin. In particular it relates to methods and devices for containing and separately dispensing a sunscreen and a UV indicator for use on the human skin, where the UV indicator is applied underneath the sunscreen on one or more small regions of the body, and is used to visually alert a user to apply more sunscreen or reduce their exposure to the sun. 
     Description of the Related Art 
     Sunscreens are widely used to reduce or prevent over exposure to ultraviolet (UV) radiation by reducing the level of UV radiation reaching the skin. Physical or inorganic sunscreens (such as those containing titanium dioxide or zinc oxide) generally operate by blocking or scattering UV radiation, whereas chemical or organic sunscreens generally operate by absorbing UV radiation. 
     A wide variety of sunscreen products are available. These sunscreens are typically commercially available as fluids, such as creams, lotions, gels and liquids, or as solids such as powders. Sunscreens are typically contained or packaged in flexible tubes or hard containers such as bottles, either plastic or metal, having dispensers such as orifices, nozzles, pumps, sprays or brushes. The packaging generally indicates the strength of UV protection afforded by the sunscreen (for example, a sun protection factor or SPF rating), and contains directions on proper application and reapplication procedures. 
     For a variety of reasons, once applied to the skin, sunscreens tend to become less effective over time. For example, the sunscreen may rub off, may be removed through sweating or immersion in water, and/or the effectiveness of the sunscreen may be reduced because of absorption into the skin or photo-degradation. Also, some sunscreens have a shelf-life and may become less effective upon prolonged storage. Generally the user cannot tell when a sunscreen is no longer providing effective or adequate UV protection. It can also be difficult for the user to know if they have applied an adequate coating of sunscreen to their skin in order to provide a desired degree of UV protection. 
     UV indicators that contain photochromic molecules, that reversibly change color upon exposure to UV radiation, are known. Formulations of such UV indicators that can be applied directly to human skin are presently being developed. Such UV indicators can be applied underneath a sunscreen as a marker on one or more small regions of the body, and used to visually alert a user to apply more sunscreen or reduce their exposure to the sun based on a change in color of the UV indicator marker. The color change that occurs when the sunscreen is no longer providing adequate UV protection can be, for example, from colored to colorless, colorless to colored, from one color to another, or can be a change in the intensity of the color, depending upon the particular UV indicator being used. UV indicators comprising molecules that change color irreversibly upon exposure to UV radiation are also known, and can be used as dosimeter-type indicators to give a visual indication of cumulative UV exposure. 
     BRIEF SUMMARY 
     Devices for containing and separately dispensing two materials for use on human skin are provided. In some embodiments, a device for containing and separately dispensing two materials for use on human skin has a primary chamber containing a sunscreen and a secondary chamber containing a UV indicator. 
     In some embodiments, a device for containing and separately dispensing two materials for use on human skin comprises a container and a double flip-top cap mounted thereto. The container defines a primary chamber for containing a primary material, and the double flip-top cap is mounted over an opening in the container. The double flip-top cap comprises a base via which it is mounted to the container and via which a primary material can be dispensed from the container. For example, the base can comprise a nozzle having an aperture. The double flip-top cap further comprises a middle section hinged to the base, the middle section serving as a flip-top lid for the container. The double flip-top cap further comprises a top section hinged to the middle section, the middle section and the top section cooperating to define a secondary chamber for containing a secondary material, and the top section serving as a flip-top lid for the secondary chamber. The primary and secondary materials have different compositions. In some embodiments, the primary material is a sunscreen and the secondary material is a UV indicator. 
     In some embodiments, a device for containing and separately dispensing two materials for use on human skin comprises a container and a dual cap assembly mounted thereto. The container defines a primary chamber for containing a primary material, and the dual cap assembly is mounted over an opening in the container. The dual cap assembly comprises a base via which it is mounted to the container and via which a primary material can be dispensed from the container. For example, the base can comprise a nozzle having an aperture. The dual cap assembly further comprises a middle section that can be removeably attached to the base to close off or provide access to the primary chamber, for example, by a snap-fit or screw thread fastening mechanism. The dual cap assembly further comprises a top section that can be removeably attached to the middle section to close off or provide access to a secondary chamber, for example, by a snap-fit or screw thread fastening mechanism. The middle section and top section cooperate to define the secondary chamber for containing a secondary material. The primary and secondary materials have different compositions. In some embodiments, the primary material is a sunscreen and the secondary material is a UV indicator. 
     In some embodiments of the devices described above, the container is a squeeze tube. In other embodiments of the devices described above, the container is a bottle. In some embodiments of the devices described above, the container is an aerosol can and the base comprises a spray nozzle. 
     In some embodiments of the devices described above, the secondary chamber contains an applicator for applying a UV indicator to human skin. The applicator can be a stamp (or die), for example. 
     Also provided are methods of using embodiments of the devices described herein to dispense and apply two materials to human skin. 
     In some embodiments, a method for dispensing two materials for application to human skin comprises: obtaining a device having a primary chamber containing a sunscreen and a secondary chamber containing a UV indicator. The method comprises opening the secondary chamber; dispensing and applying a quantity of the UV indicator from the secondary chamber to a first portion of the skin of a user; closing the secondary chamber; opening the primary chamber; dispensing a quantity of sunscreen from the primary container and applying it over the UV indicator on the first portion of the skin of the user and to a second portion of the skin of the user; and closing the primary chamber. 
     In other embodiments, a method for dispensing two materials for application to human skin comprises: obtaining a device having a container defining a primary chamber containing sunscreen and a double flip-top cap mounted to the container, the double flip-top cap comprising a secondary chamber containing a UV indicator; flipping open a hinged top section of the double flip-top cap to provide access to the secondary chamber, for example by partially disengaging the top section from a middle section of the double flip-top cap; dispensing and applying a quantity of the UV indicator from the secondary chamber to a first portion of the skin of a user, for example, using a stamp located in the secondary chamber; closing the top section of the double flip-top cap, for example, by re-engaging the hinged top section with the middle section; flipping open a hinged middle section of the double flip-top cap to provide access to the primary chamber, for example, by partially disengaging the middle section from a base of the double flip-top cap; dispensing a quantity of sunscreen from the primary chamber via the base and applying it over the UV indicator on the first portion of the skin of the user and to a second portion of the skin of the user; closing the middle section of the double flip-top cap, for example, by re-engaging the hinged middle section with the base. 
     In still further embodiments, a method for dispensing two materials for application to human skin comprises: obtaining a device comprising a container defining a primary chamber containing sunscreen and a dual cap assembly mounted to the container, and the dual cap assembly comprising a secondary chamber containing a UV indicator; separating a top section of the dual cap assembly from a middle section of the dual cap assembly to provide access to the secondary chamber; dispensing and applying a quantity of the UV indicator from the secondary chamber to a first portion of the skin of a user, for example, using a stamp located in the secondary chamber; re-attaching the top section of the dual cap assembly to the middle section of the dual cap assembly to close off the secondary chamber; separating the middle section of the dual cap assembly from a base of the dual cap assembly to provide access to the primary chamber; dispensing a quantity of sunscreen from the primary chamber via the base and applying it over the UV indicator on the first portion of the skin of the user and to a second portion of the skin of the user; re-attaching the middle section of the dual cap assembly to the base dual cap assembly to close off the primary chamber. 
     These and other features, and advantages of the present invention will become more readily apparent from the attached drawings and the detailed description of preferred embodiments, which follow. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side view of an embodiment of a device for containing and separately dispensing materials for use on human skin, the device comprising a primary chamber and a double flip-top cap comprising a secondary chamber; 
         FIGS. 2A, 2B, 2C, and 2D  are various different views of the double flip-top cap shown in  FIG. 1 ; 
         FIGS. 3A and 3B  are top and side cutaway views of the base of the double flip-top cap shown in  FIG. 1 ; 
         FIGS. 4A, 4B and 4C  are underside, top and side views of the middle section of the double flip-top cap shown in  FIG. 1 , and  FIGS. 4D, 4E and 4F  are top, underside, and side views of the top section of the double flip-top cap shown in  FIG. 1 ; 
         FIGS. 5A, 5B, 5C and 5D  are side views of the double flip-top cap shown in  FIG. 1  with the hinged sections in different positions; 
         FIG. 6  is a cross-sectional side view of an embodiment of a dual cap assembly mounted on a container; 
         FIG. 7  is a cross-sectional side view of another embodiment of a dual cap assembly mounted on a container; 
         FIG. 8  is a side view of another embodiment of a device for containing and separately dispensing materials for use on human skin, the device comprising a spray can and a cap assembly comprising a spray nozzle and a secondary chamber; 
         FIG. 9  is a side view of another embodiment of a device for containing and separately dispensing materials for use on human skin, the device comprising a spray can and cap assembly with a container/applicator detachably mounted thereto. 
         FIG. 10  is a side view of a double flip-top cap according to another embodiment. 
         FIG. 11  is a side view of a double flip-top cap according to another embodiment. 
     
    
    
     Like reference numerals refer to like parts throughout the several views of the drawings. 
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     As used herein, the term “sunscreen” includes materials sold for use on human skin to reduce exposure of the skin to UV radiation and protect exposed skin from sunburn, for example, by absorbing, scattering and/or blocking UV radiation. Sunscreens include fluids such as creams, lotions, liquids, gels, sprays and balms, and include solids such as powders. 
     As used herein, the term UV indicator refers to materials comprising one or more types of photochromic molecules that change color when exposed to UV radiation. The color change is preferably reversible, but in some embodiments is irreversible. UV indicators can include fluids such as solutions, suspensions, inks or gels comprising photochromic molecules, or solids such as powders comprising photochromic molecules. 
     Referring to  FIG. 1 , an embodiment of a device  10  for containing and separately dispensing two materials for use on human skin is shown. Device  10  comprises a container  14 , and a double flip-top cap  12  mounted on container  14 . Although container  14 , is illustrated in  FIG. 1  as a flexible squeeze tube it can be, for example, a hard-walled container such as a bottle or can. In different embodiments, walls  16  of primary container  14  can be made of flexible or rigid plastic, flexible or rigid metal, glass, composite materials or other suitable materials. Walls  16  define a primary chamber (i.e., an interior volume of container  14 ) containing a primary material, such as a sunscreen  58 . 
     Double flip-top cap  12  comprises a base  32  via which it is mounted to container  14  and via which sunscreen  58  is dispensed. A middle section  30  of cap  12  is hinged to base  32  and serves as a flip-top lid or closure for container  14  for closing off and providing access to the primary chamber. A top section  24  of cap  12  is hinged to middle section  30 . Middle section  30  and top section  24  cooperate to define a secondary chamber containing an indicator (as shown in further detail in reference to  FIGS. 4 and 5  below). Top section  24  serves as a flip-top lid or closure for closing off and providing access to the secondary chamber. The secondary chamber can contain a secondary material, such as a UV indicator. 
     A primary material, such as sunscreen  58  can be dispensed from within container  14  via base  32  when middle section  30 , serving as a flip-top lid, is opened. When middle section is in a closed position, as shown in  FIG. 1 , primary chamber in container  14  is closed off or substantially sealed. A secondary material, such as a UV indicator, can be dispensed from the secondary chamber when top section  24 , serving as a flip-top lid, is opened. When top section  24  is in a closed position, as shown in  FIG. 1 , the secondary chamber is closed off or substantially sealed. Base  32  is typically mounted to container  14  connected by a screw thread fastening mechanism (see  FIGS. 6 and 7 ). 
       FIGS. 2A, 2B, 2C and 2D  are right-side, left-side, front and top views, respectively, of the double flip-top cap  12  shown in  FIG. 1 . Flexible hinges  34  and  36  attach top section  24  to middle section  30 , and middle section  30  to base  32 , respectively. Hinges  34  and  36  are preferably on opposite sides of the double flip-top cap  12  as shown in  FIGS. 2A and 2B , so that when one section ( 30  or  24 ) is flipped to an open position, the other section has less tendency to open at the same time. In other embodiments the flexible hinges  34 ,  36  could be on the same side of the cap or at some other position relative to one another. The double flip-top cap  12  is typically made of plastic, and flexible hinges  34  and  36  can be made of thin plastic integrally formed with the rest of the cap, as is conventional and is well known to those skilled in the art. In some embodiments, the top section  24  and the middle section  30  can be formed together, the base  32  formed separately and these two parts connected via, for example, a slip-fit connection to form hinge  34 . In some embodiments, the base  32  and the middle section  30  can be formed together, the top section  24  formed separately and these two parts connected via, for example, a slip-fit connection forming hinge  36 . Indents  38  and  40  shown in  FIG. 2C  provide an area upon which fingers can grip to open the flip-top lids (sections  24  and  30  respectively). 
       FIGS. 3A and 3B  illustrate a top view and a side cutaway view, respectively, of base  32  of double flip-top cap  12 . Base  32  comprises a protruding nozzle  43 , with opening or aperture  44  formed therethrough, via which the primary material such as sunscreen  58  can be dispensed from a container to which base  32  is mounted. As shown in  FIG. 3B , base  32  is internally threaded with threads  42  via which it can be mounted to an externally threaded container. 
       FIGS. 4A-C  show an underside view, a top view and a side view, respectively, of the middle section  30  of double flip-top cap  12 . Middle section  30  has a recess  46  formed therein that fits over protruding nozzle  43  of base  32 , to prevent leakage of material via aperture  44 , when middle section  30  is in a closed position with respect to base  32 . In other embodiments, middle section  30  may comprise a plug that inserts into aperture  44  to block it when middle section is in a closed position. Other suitable sealing mechanisms that will be apparent to those skilled in the art may be incorporated into middle section  30  and/or base  32  for this purpose. Middle section  30  also comprises another recess  48  containing a stamp  50  that may be impregnated or soaked with the secondary material, such as a UV indicator ink. The stamp can be made of a polymer foam or a sponge-like rubber or other suitable material. It may be patterned with an image or design such as image  52 .  FIGS. 4D-F  show a top view, an underside view and a side view, respectively, of the top section  24  of double flip-top cap  12 . Top section  24  has a recess  54  to that fits over and accommodates stamp  50  that protrudes from recess  48  in middle section  30 . Thus, top section  24  and middle section  30  cooperate to define a secondary chamber  56 , formed by recesses  54  and  48 , for containing a secondary material, which in the illustrated embodiment is a UV indicator ink stored in stamp  50 . In the illustrated embodiment, recesses  48  and  54  have approximately the same dimensions. In some embodiments there is a patterned stamp located in one recess (for example recess  48 ) and an ink pad located impregnated with a UV indicator ink located in the other recess (for example, recess  54 ). When top section  24  is in a closed position the stamp is in contact with the pad to wet or load the stamp with ink. In some embodiments, an ink well can be provided to be in fluid communication with an ink pad, which ink pad can wet or load the stamp with ink as illustrated in  FIG. 11  and described in more detail below. 
     In some embodiments the stamp and/or ink pad are readily removable so that they can be replaced or refilled. In some embodiments recesses  48  and  54  are different sizes or depths, and in some embodiments there is a recess in only one of the top section  24  or middle section  30 . 
     A gasket or other suitable sealing mechanism (not shown) can be used to substantially seal secondary chamber  56  when top section  24  is in a closed position with respect to middle section  30 , so that secondary material (such as a UV indicator) does not leak from secondary chamber  56 , and so that there is less tendency for stamp  50  and/or an ink pad (if present) in the secondary chamber to dry out. 
       FIGS. 5A, 5B, 5C, and 5D  illustrate views of double flip-top cap  12  with the hinged sections in different positions. In  FIG. 5A  middle section  30  is engaged with base  32  and top section  24  is engaged with middle section  30 , so both flip-top lids (sections  30  and  24 ) are in a closed position. A snap-fit mechanism or other suitable mechanism can be used so that a reasonable degree of manual force is required to open the lids, so that there is less tendency for them to open accidently when device  10  is not in use. In  FIG. 5B  middle section  30  is pivoted to an open position. In  FIG. 5C  top section  24  is flipped or pivoted to an open position. In  FIG. 5D  both middle section  30  and top section  24  are flipped or pivoted to an open position. Nozzle  44  and recesses  46 ,  48  and  54  are shown with dotted lines in  FIGS. 5A and 5C . 
     A method of use of device  10  having double flip-top cap  12  such as shown in  FIGS. 1-5  is as follows: hinged top section  24  is flipped open and the exposed stamp  50  having the UV indicator material therein is used to apply a quantity of UV indicator to a small region of the skin in areas of high exposure such as the arms, shoulders, or back. Hinged top section  24  is closed and then hinged middle section  30  is opened by flipping it in the opposite direction from how top section  24  was opened. Sunscreen is dispensed from the primary chamber in container  14 ; the sunscreen material is applied over the UV indicator that was applied to a small region of the skin and to other portions of the user&#39;s sun-exposed skin as desired. The UV indicator may be applied as any suitable mark or shape such as a round spot or in a predetermined design such as a flower, animal, etc. The applied UV indicator will change color based upon the intensity and length of exposure to UV radiation through the sunscreen. The device may include directions as to the significance of different colors or levels of color saturation. A bright red spot, for example, may provide a warning that additional sunscreen should be applied. 
     The double flip-top cap as shown above has two hinged sections. Other suitable mechanisms may be used for removeably attaching or fastening various sections of a cap assembly to one another. The cap can comprise snap-fit, push-on or screw-on sections or a combination of attachment mechanisms. For example, in some embodiments one or both hinges  34  and  36  are omitted, and middle section  30  removeably snap-fits to base  32  and/or top section  24  removeably snap-fits to middle section  30  (such as shown in  FIG. 7  below). In other embodiments (such as shown in  FIG. 6  below) middle section  30  is removeably fastened to base  32  and/or top section  24  is removeably fastened to middle section  30  by a screw thread fastening mechanism. In general the hinges are more convenient for ease of use of the device, and for keeping the components of the device together. 
     Thus, double flip-top cap  12  illustrated in  FIGS. 1-5  can allow a single device to be used to store and dispense two materials for application to human skin, that are to be used in association with one another. The double flip-top cap  12  is a convenient way of sealing and providing access to a primary chamber in container  14  to which the cap is mounted, and to a secondary chamber within the cap  12  itself. The double flip-top cap thereby facilitates storage and separate dispensing of a primary material and a secondary material for use on human skin, and in particular storage and separate dispensing of a sunscreen and a UV indicator. The indicator can be applied to the skin using a stamp or other suitable applicator that is contained within the secondary chamber. 
     Some alternative embodiments of devices for storing and separately dispensing a sunscreen and a UV indicator are illustrated in  FIGS. 6-11 . 
     In the embodiment shown in  FIG. 6  a dual cap assembly  612  is mounted to a container  614  (only partially shown in  FIG. 6 ). Dual cap assembly comprises base  632  which is mounted to container  614  by a screw thread fastening mechanism. Base  632  has a nozzle  643  (with an aperture therethrough) for dispensing sunscreen from container  614 . Middle section  630  removeably snap-fits on to base  632 , with recess  646  accommodating nozzle  643  to close off container  614  and preferably form a seal over the aperture in nozzle  643 . Top section  624  removeably screws on to middle section  630  by a screw thread fastening mechanism. Sections  624  and  630  define a secondary chamber holding an inked stamp  650  and optionally an ink pad (not shown). 
     In the embodiment shown in  FIG. 7  a dual cap assembly  712  is mounted to a container  714  (only partially shown in  FIG. 7 ). Dual cap assembly comprises base  732  which is mounted to container  714  by a screw thread fastening mechanism. Base  732  has a nozzle  743  (with an aperture therethrough) for dispensing sunscreen from container  714 . Middle section  730  removeably snap-fits on to base  732 , with recess  746  accommodating nozzle  743  to close off container  714  and preferably form a seal over the aperture in nozzle  743 . Top section  724  snap-fits on to middle section  730 . Sections  724  and  730  define a secondary chamber holding an inked stamp  750  and optionally an ink pad (not shown). 
       FIG. 8  shows a device  800  for containing and separately dispensing two materials for use on human skin, the device  800  comprising an aerosol or pump-spray container  814  having a dual cap assembly  812  mounted thereon. Sunscreen is dispensed from container  814  via a nozzle  843  in base  832  by pressing down on dual cap assembly  812 . Dual cap assembly  812  further comprises a middle section  830  and top section  824 . Top section can be a flip-top lid, a screw-on lid, a snap-fit lid or the like as described above. Middle section  830  and top section  824  define a secondary chamber  866  containing a UV indicator for use with the sunscreen in container  814 . Middle section can be integrally formed with base  832 , or can be fixed to base  832  or can be removeable attached to base  832 . 
       FIG. 9  shows a device  900  for containing and separately dispensing two materials for use on human skin, the device  900  comprising an aerosol or pump-spray container  914  having a cap assembly  912  mounted thereon. Sunscreen is dispensed from container  914  via a nozzle  943  in base  932  by pressing down on cap assembly  912 . Cap assembly  912  further comprises a flexible clip  970  via which a container/applicator device such as pen  990   a , brush  990   b  or stamp  990   c  can be removeably mounted to base  932 . Container/applicator device  990  contains a UV indicator which can be applied to human skin using the device, for use in association with sunscreen stored in container  914 . A removable cap  995  is used to close off or seal container/applicator device when not in use. Flexible clip  970  can be integrally formed with base  932  or can be fastened to base  932  using an adhesive or glue  974  as shown in  FIG. 9 . 
       FIG. 10  shows a side view of a double flip-top cap  1112  according to another example embodiment. The double flip-top cap  1112  can be mounted to a wide variety of containers, for example, containers  14 ,  614 ,  714 ,  814 , etc., which have not been shown for clarity of illustration and description. The double flip-top cap  1112  is generally similar to the double flip-top cap  12 , but provides a variation in which the double flip-top cap  1112  includes an ink well recess  1144  that partially extends through a middle section  1130 . In particular, the ink well recess  1144  is located below a recess  1148  that extends through the middle section  1130  from an upper surface of the middle section  1130 . The ink well recess  1144  is sized and shaped to receive UV indicator ink. In this manner, a secondary chamber  1156  is defined at least in part by a recess  1154  disposed in a top section  1124 , the recess  1148  and the ink well recess  1144  disposed in the middle section  1130 . 
     In this embodiment of the double flip-top cap  1112 , a self-inking UV applicator  1150 , e.g., a foam stamp, is positioned in the recess  1148  of the middle section  1130 , with an upper portion protruding outwardly from the recess  1148  of the middle section  1130  and into the recess  1154  of the top section  1124 . A lower side of the self-inking UV applicator  1150  is positioned adjacent to the ink well recess  1144  and is in fluid communication with the ink well recess  1144 . Providing an ink well recess  1144  in fluid communication with the UV applicator  1150  allows the UV applicator  1150  to become re-saturated between uses and provides a metered volume of ink. The metered volume of ink material generally results in a relatively consistent thickness of the ink layer deposited on the skin of the user, which positively contributes to a perceived depth of color change when the UV indicator ink, e.g., photochromic dye, is exposed to UV radiation. For example, the protrusion of the UV applicator  1150  above a rim of the middle section  1130  can result, upon re-saturation of the UV applicator  1150  and a standardized compression of the UV applicator  1150 , in deposition of approximately similar amounts of ink. 
     Moreover, the positioning of the self-inking UV applicator  1150  adjacent to the ink well recess  1144  and in fluid communication with the UV indicator ink disposed therein allows for re-saturation of the self-inking UV applicator  1150 . For instance, the ink well recess  1144  and the self-inking UV applicator are sized and shaped to allow capillary forces to pull or draw the UV indicator ink disposed in the ink well recess  1144  toward the self-inking UV applicator  1150  to re-saturate the UV applicator  1150 . In some instances, the re-saturation of the UV applicator  1150  via capillary forces can work in tandem with gravitational forces. For instance, when a device having the double flip-top cap  1112  coupled to a container is positioned with an exterior surface of the top section  1124  facing or abutting a horizontal or an inclined surface, the gravitational forces along with the capillary forces can direct or draw the UV indicator ink toward the UV applicator  1150  and re-saturate the UV applicator  1150 . In some instances, when the device is positioned on a horizontal or an inclined surface such that a right side or a left side of the device is facing or abutting the horizontal or the inclined surface, the gravitational forces along with the capillary forces can direct or draw the UV indicator ink toward the UV applicator  1150  and re-saturate the UV applicator  1150 . Again, providing the ink well recess  1144  and positioning the ink well recess  1144  adjacent to the UV applicator  1150  in this manner advantageously allows for re-saturation of the UV applicator  1150  which, in conjunction with the UV applicator  1150  extending above the rim of the middle section  1130  and compressed a standardized amount when pressed against the user&#39;s skin (contact with the upper rim of middle section  1130  with the user&#39;s skin determining the amount of compression), allows for a relatively consistent metering of the ink layer deposited on the skin of the user between uses and through the lifecycle of the device. 
     Moreover, the self-inking UV applicator  1150  described above can be provided in a wide variety of devices. For example, the device  614  illustrated in  FIG. 6  can include an ink well recess disposed in the middle section  630  with UV indicator ink disposed in the ink well recess to pull or draw the UV indicator ink to re-saturate the UV applicator  1150 . Similarly, the middle sections  730 ,  830  of corresponding dual cap assembly  712  and device  800  can also include an ink well recess to pull or draw the UV indicator ink to re-saturate the UV application  1150 . 
       FIG. 11  illustrates a double flip-top cap  2112  according to another example embodiment. The double flip-top cap  2112  provides a variation in which it includes a stamp  2050  located in one recess (for example recess  2048  of a middle section  2030 ) and an ink pad  2070  impregnated with a UV indicator ink located in another other recess (for example, recess  2054  of a top section  2024 ). The double flip-top cap  2112  also includes an ink well  2071  located in the top section  2024  that includes UV indicator ink and is in fluid communication with the ink pad  2070 . When top section  2024  is in a closed position, the stamp  2050  is in contact with the ink pad  2070  to wet or load the stamp  2050  with ink. The UV indicator ink in the ink well  2071  can saturate or re-saturate the ink pad  2070 . 
     Since many modifications, variations, and changes in detail can be made to the described embodiments of the invention, it is intended that all matters in the foregoing description and shown in the accompanying drawings be interpreted as illustrative and not in a limiting sense. Thus, the scope of the invention should be determined by the appended claims and their legal equivalents. 
     The various implementations, examples, and embodiments described above can be combined to provide further implementations, examples, and embodiments respectively. To the extent that they are not inconsistent with the specific teachings and definitions herein, all of the U.S. patents, U.S. patent application publications, U.S. patent applications, foreign patents, foreign patent applications and non-patent publications referred to in this specification and/or listed in the Application Data Sheet are incorporated herein by reference, including but not limited to U.S. Provisional Patent Application Ser. No. 62/338,235 filed May 18, 2016.