Wet wipes container with improved closure

A wet wipe container having improved opening and improved tear resistance between the lid and the base among other features. The container includes a container base and a container lid that is connected to the container base. In one embodiment, the container lid has a guide ridge that extends downward into the interior of the container. The guide ridge permits the container lid to be in a partially open position and provides better alignment between the container lid and the container base during closing of the container. In another embodiment, the container includes a closure that has an upwardly extending tongue projection, a flattened grip area and an assistive region to increase the ease with which the container can be opened. The invention also relates to a container having a more tear resistant container lid. The container lid has a hinge channel of a primary thickness. The hinge channel has two end regions that are of a secondary thickness that is greater than the primary thickness. The increased thickness of the end regions resists the tearing that can occur in the lid after repeated opening and closing of the container.

FIELD OF THE INVENTION
 The present invention relates to a container for premoistened wipes. The
 invention particularly concerns container lids and container bases that
 secure to each other more easily. The engagement between the container lid
 and the container base is facilitated by structural guides that better
 position the lid on top of the base and by an improved closure. The
 invention also concerns an improvement in the tear resistance of the
 container lid and an improvement in the compression strength of the
 container.
 DESCRIPTION OF THE RELATED ART
 Wet wipes are well known commercial consumer products which have been
 available in many forms. Perhaps the most common form of wet wipes has
 been a stack of moistened sheets which have been packaged in a plastic
 container. The wet wipes have been made from a variety of materials which
 have been moistened with a variety of suitable wiping solutions.
 Typically, the wet wipes have been stacked in the container in either a
 folded or unfolded configuration. For example, containers of wet wipes
 have been available wherein each of the wet wipes stacked in the container
 has been arranged in a folded configuration such as a c-folded, z-folded
 or quarter-folded configuration as are well known to those skilled in the
 art. Some of the folded wet wipes have also been interfolded with the wet
 wipes immediately above and below in the stack of wet wipes. In an
 alternative configuration, the wet wipes have been placed in the container
 in the form of a continuous web of material which includes perforations to
 separate the individual wet wipes and which is wound into a roll. Such wet
 wipes have been used for baby wipes, hand wipes, household cleaning wipes,
 industrial wipes and the like.
 The conventional packages which contain wet wipes, such as those described
 above, have typically been designed to be positioned on a flat surface
 such as a countertop. Such conventional packages have generally provided a
 plastic container or tub which provides a sealed environment for the wet
 wipes to ensure that they do not become overly dry. Some of the
 conventional packages have also been configured to provide one at a time
 dispensing of each wet wipe which can be accomplished using a single hand
 after the package has been opened. Such single handed, one at a time
 dispensing is particularly desirable because the other hand of the user or
 care giver is typically required to be simultaneously used for other
 functions. For example, when changing a diaper product on an infant, the
 care giver typically uses one hand to hold and maintain the infant in a
 desired position while the other hand is attempting to dispense a baby
 wipe to clean the infant
 However, the opening of such conventional containers for wet wipes has not
 been completely satisfactory. For example, many conventional containers
 are not capable of being opened by a single hand or, if designed for
 opening by a single hand, are not easy to open with a single hand for all
 users. In such containers, the user typically has to open the package with
 both hands before dispensing a wet wipe. Many of such containers have been
 hard to open because they have included a cover which provides a positive
 frictional seal with the container body when closed to ensure that the wet
 wipes do not become overly dry. In addition, many conventional containers
 have included relatively small opening mechanisms which are difficult to
 manipulate with a single hand.
 Another difficulty associated with conventional containers for wet wipes is
 that the lids of the containers typically must either be completely open
 or completely closed. Depending on the weight of the wet wipes remaining
 in the container, the container may tip backwards from the weight of an
 open lid. Therefore, conventional containers do not provide for a
 partially open position between the lid and the base of the container.
 Consequently, as the supply of wet wipes in the container is depleted, it
 becomes more difficult to obtain a wipe from the container using a single
 hand. In some conventional containers, there is poor alignment between the
 container lid and the container base. The poor alignment hinders the
 user's ability to secure the lid to the base, particularly when the
 operation must be done with a single hand.
 With some wet wipe uses, such as with wet wipes for diaper changes, the
 container holding the wipes is opened and closed with great frequency.
 Frequent opening and closing of the container lid causes wear and stress
 on the connection or attachment between the lid and the base. After a
 number of opening and closing cycles, the connection can begin to fail
 and, in some cases, will result in the container lid tearing away from the
 container base. The rough surface produced by a torn lid can catch on skin
 or on fabric, thus becoming a nuisance. In the past, the exterior contours
 of some conventional containers have had right angles with rough edges
 that can catch on skin or fabric. For example, right angles often exist at
 the connection point between container lids and container bases.
 During shipping and storage of the containers, the containers are often
 stacked vertically on top of each other. The stacking can be done on a
 pallet or within a shipping/storage container. The vertical stacking of
 the containers on top of each other results in a substantial force acting
 on the top of the container. If the container does not have sufficient
 compressive strength, the lid or base can become deformed by outward
 bowing or buckling. Some conventional containers have not been designed to
 withstand the magnitude of force experienced during routine shipping and
 storage.
 SUMMARY OF THE INVENTION
 In response to the difficulties and problems discussed above, a new
 container for wet wipes that has improved opening and dispensing, is
 capable of maintaining a partially open position, has improved alignment
 between lid and base, has improved tear resistance and has improved
 compression strength has been discovered. The purposes and advantages of
 the present invention will be set forth in and apparent from the
 description that follows, as well as will be learned by practice of the
 invention. Additional advantages of the invention will be realized and
 attained by the containers particularly pointed out in the written
 description and claims hereof, as well as from the appended drawings.
 In one aspect, the present invention relates to a wet wipe container that
 includes a container base and a container lid. The container lid is
 connected to the container base. The container lid and the container base
 can be a single component or can be separate components. The connection
 between the container lid and the container base can be in the form of an
 ultrasonic bond, an interlocking hinge or other form of connection known
 in the art. The container lid has a top and a front wall, a rear wall and
 a pair of opposed side walls. The walls extend downwardly from the top of
 the container lid in a generally rectangular configuration. The walls can
 also extend downward in a generally trapezoidal configuration. The
 container base has a bottom and a front wall, a rear wall, and a pair of
 opposed side walls. The walls extend upwardly from the bottom of the
 container base in a generally rectangular configuration to provide an
 interior for containing the wet wipes. The walls can also extend upward in
 a generally trapezoidal configuration.
 The top of the container lid has a downwardly extending guide ridge. The
 rear wall of the container lid defines a length that is approximately the
 same as the overall length of the container. The guide ridge is generally
 parallel to the rear wall of the container lid and the guide ridge is
 located close to or proximate the rear wall. The guide ridge has a length
 that is less than the length of the rear wall. For example, the ratio of
 the length of the guide ridge to the length of the rear wall, which
 generally represents the length of the container, can be desirably, but
 not exclusively, from about 40% to about 90%. Further, the guide ridge can
 extend downward a distance of from about 0.25 inches to about 0.75 inches.
 The guide ridge can also have a thickness that is from about 0.0625 inches
 to about 0.25 inches. The rear wall of the container base has an upper
 portion that defines a receiving edge. The receiving edge is generally
 configured to receive the guide ridge of the container lid. For example,
 the receiving edge can be arc-shaped. The receiving edge gradually
 receives the guide ridge as the container lid is rotated from an open
 position to a closed position. Among other things, the guide ridge
 facilitates single hand opening and closing of the container. Further, the
 guide ridge improves the alignment between the container lid and the
 container base. The guide ridge also permits a partially open position of
 the container lid. The container is stable and does not tip over when the
 container lid is partially open, even if there are only a few wet wipes
 remaining in the container. In the partially open position, the container
 lid is from about 1.5 inches to 3.0 inches above the container base. The
 partially open position allows a person to reach into the container to
 pick up a wet wipe with only one hand.
 The container lid can be fabricated from a polymer, copolymer or mixtures
 of both. For example, the container lid can be made primarily of a
 copolymer of styrene-butadiene-styrene. The container lid can be
 transparent or translucent to, in part, facilitate determination of the
 quantity of wipes remaining in the container. The container base can
 likewise be fabricated from a polymer, copolymer or mixtures of both. For
 example, the container base can be primarily made of polystyrene. The
 container base can be made of either an opaque, translucent or transparent
 material. Dyes, tints and colorants can be added to the material of either
 the container lid or the container base. The wet wipe containers of the
 invention can be beneficially used for secondary purposes when they are no
 longer used to contain wet wipes. For example, the containers can be used
 to store small toys, art supplies and other household items. When the
 container lid and container base are translucent or transparent, it is
 possible to see what is inside of the container without opening the lid.
 The corners that are formed at the intersections of the various walls of
 the container lid and the container base can be rounded. More
 particularly, the corners between the front walls, the rear walls, the
 side walls, the top and the bottom can be curvilinear. The container lid
 and the container base can be joined together at their respective rear
 walls. The container lid and the container base can be joined or connected
 by the variety of ways known in the art including by ultrasonic bonds.
 In another aspect, the present invention relates to a wet wipe container
 including a container base and a separate container lid that is attached
 to the container base. The container lid can be attached to the container
 base in a variety of ways including by a hinge arrangement, by pins, by
 interlocking edges, by ultrasonic bonding and other ways of attachment
 known in the art. The container lid has a top and a front wall, rear wall
 and a pair of opposed side walls. The walls extend downwardly from the top
 in a generally rectangular configuration.
 The rear wall of the container lid includes an outwardly extending flange.
 The outwardly extending flange can be primarily two-dimensional and,
 therefore, the flange has a width and a length. The flange can be thought
 of as being divided into three areas: the area immediately adjacent the
 rear wall of the container lid, a hinge channel and an attachment area.
 The attachment area is located most distally to the rear wall of the
 container lid and the hinge channel is located between the immediately
 adjacent area and the attachment area. The three areas are primarily
 linear and they are configured to be generally parallel to each other and
 to the rear wall of the container lid. Each of the areas has an
 independent length that is no greater than the length of the rear wall of
 the container lid. Starting from the area near the rear wall, the length
 of the flange can gradually taper along the width of the flange. In this
 case, the length of the flange near the rear wall would be greater than
 the length of the flange at the attachment area. The length of the hinge
 channel would be between the lengths of the area near the rear wall and of
 the attachment area. For example, the ratio of the length of the flange at
 the hinge channel to the total length of the container lid can be from
 about 60% to about 85% and the ratio of the length of the flange at the
 attachment area to the total length of the container lid can be from about
 50% to about 75%.
 The hinge channel has two end regions, each end region being located at an
 end of the hinge channel. The hinge channel has a primary thickness and
 the end regions of the hinge channel have a secondary thickness that is
 greater than the primary thickness. The primary thickness of the hinge
 channel can be from about 0.005 inches to about 0.015 inches. The
 secondary thickness of the end regions can desirably be from about 20% to
 about 100% greater than the primary thickness.
 In addition to the thickness of the hinge channel, there is an overall
 thickness to the outwardly extending flange. The thickness of the flange
 can vary over the width of the flange. For example, the flange thickness
 includes the thickness near the rear wall, the secondary thickness of the
 end region of the hinge channel and the thickness of the attachment area.
 If the thickness of the flange near the rear wall of the container lid and
 of the attachment area are greater than the secondary thickness, the
 thickness of the flange can gradually decrease along the width until the
 thickness matches the secondary thickness. Conversely, if the thickness of
 the flange near the rear wall and of the attachment area are less than the
 secondary thickness, the thickness of the flange can gradually increase
 along the width until the thickness matches the secondary thickness. The
 outwardly extending flange has two ends that are generally defined by the
 width of the flange. These ends can have a curvilinear shape that forms an
 angle of less than ninety degrees away from the rear wall of the container
 lid. The gradual curve to the ends of the flange can prevent skin and
 fabric from catching on the flange.
 The wet wipe container also includes a container base that includes a
 bottom and a front wall, rear wall and a pair of opposed side walls. The
 walls extend upward from the bottom of the container base in a generally
 rectangular configuration that provides an interior for containing the wet
 wipes. The walls can also extend upward in a generally trapezoidal
 configuration. The rear wall of the container base can have a top portion
 that includes an outwardly extending lip. The container lid can be
 attached to the container go base by attaching the attachment area of the
 container lid to the outwardly extending lip of the rear wall of the
 container base. The container lid and the container base can be attached
 to each other by various methods known in the art including an
 interlocking hinge, by pins and by ultrasonic bonding.
 The container lid and the container base can be either transparent or
 translucent to provide an indication of the quantity of wet wipes
 remaining in the container. The container lid and the container base can
 be made of various polymers, copolymers, and mixtures including
 polystyrene and mixtures including polystyrene. The various corners formed
 by the front walls, rear walls, side walls, the top and the bottom of the
 container lid and the container base can be curvilinear.
 In another aspect, the present invention relates to a wet wipe container
 that includes a container base, a container lid and a closure. The
 container lid is connected to the container base and either the container
 lid itself can include a hinge or a hinge can be formed between the
 container lid and the container base. As an example of the connection
 between lid and base, the container lid and the container base can be
 ultrasonically bonded together. The closure is configured to releasably
 hold the container lid on the container base in a closed position.
 The closure includes an upright tongue projection that is continuous with
 and extends upward from a top surface of a front wall of the container
 base. The upright tongue projection can have curved edges and a flattened
 grip area that is generally in the center of the tongue projection. The
 top surface of the front wall of the container base can have an arcuate
 depression below the grip area of the tongue projection. The closure also
 includes an assistive region that is below the arcuate depression and is
 generally concentric with the tongue projection. The closure also includes
 an aperture that is located in a convex portion of a front wall of the
 container lid. When the container is closed, the tongue projection extends
 upward through the aperture. In another embodiment, the tongue projection
 extends downward from the container lid and the aperture is located within
 a convex portion of the container base.
 The container lids of containers having such closures can further include a
 top and a rear wall and a pair of opposed side walls that extend
 downwardly from the top in a generally rectangular configuration. The
 container bases of containers having such closures can further include a
 bottom and a rear wall and a pair of opposed side walls that extend
 upwardly from the bottom in a generally rectangular configuration to
 provide an interior for containing the wet wipes. The container base can
 also have a generally trapezoidal configuration.
 As with the other containers of the invention, the container lid and the
 container base can be transparent or translucent to provide an indication
 of the quantity of wet wipes remaining in the container. The container lid
 and the container base can be made of various polymers, copolymers, and
 mixtures including polystyrene and mixtures including polystyrene. The
 various corners formed by the front walls, rear walls, side walls, the top
 and the bottom of the container lid and the container base can be
 curvilinear.
 In yet another aspect, the present invention relates to a wet wipe
 container that includes a container base and a container lid that is
 connected to the container base. The container base includes a bottom and
 a front wall, rear wall and a pair of opposed side walls. The walls extend
 upwardly from the bottom in a generally rectangular configuration to
 provide an interior for containing the wet wipes. The walls can include
 one or more generally linear ribs that are formed into the walls. The ribs
 can be vertical or horizontal.
 The ribs can extend along the entire length or width of the wall(s) or the
 ribs can extend only along a portion of the length or width of the
 wall(s). The ribs provide the container with improved compression strength
 to resist the crushing or buckling that may occur during shipping and
 storage. The ribs also provide a more aesthetic appearance to the
 container.
 Thus, the present invention, in its various aspects, advantageously relates
 to a container for wet wipes that, when compared to conventional
 containers of wet wipes, provides convenient single handed access to the
 wet wipes. In particular, the present invention provides an aesthetically
 pleasing container for wet wipes that has an easy-to-use and ergonomic
 closure. The improved closure provides reliable single handed opening and
 dispensing for improved consumer acceptance. The containers are
 particularly desirable for baby wipes intended for use in the typical
 diaper changing routine in which usually only one of the hands of the
 care-giver is available for retrieval of a wet wipe. Further, the
 container of the invention is stable in a partially open position
 regardless of the quantity of wet wipes in the container. Being able to
 maintain a partially open position of the lid prevents the weight of the
 container lid from tipping the container backwards when only a small
 quantity of wet wipes remain in the container. The container also provides
 improved alignment between the container lid and the container base,
 thereby further assisting single hand operation. Advantageously, the
 container of the invention has a lid that is more tear resistant under
 repeated use than conventional lids and a curved edge contour that
 prevents skin or fabric from catching on an edge of the container.
 Additionally, the container of the invention provides better compression
 strength and, therefore, improved resistance to crushing and buckling.
 It is to be understood that both the foregoing general description and the
 following detailed description are exemplary and are intended to provide
 further explanation of the invention claimed. The accompanying drawings,
 which are incorporated in and constitute part of this specification, are
 included to illustrate and provide a further understanding of the
 containers of the invention. Together with the description, the drawings
 serve to explain the various aspects of the invention.

DETAILED DESCRIPTION OF THE INVENTION
 The present invention is directed at solving problems related to the use
 and durability of conventional containers for wet wipes. As
 representatively illustrated in FIGS. 1-8, the present invention provides
 a wet wipe container 20 that is configured to dispense wet wipes in a
 convenient and reliable manner for personal use. The wet wipe container 20
 includes a container base 22 and a container lid 24 that is connected or
 attached to the container base 22. The container base 22 and the container
 lid 24 can be formed as a single piece or they can be separate pieces. The
 container lid 24 can be connected to the container 22 by various
 mechanical and chemical methods known in the art, including, but not
 limited to, hinges, interlocking members, use of glue or other bonding
 material or ultrasonic bonding.
 The wet wipes may be arranged in the container 20 in any manner which
 provides convenient and reliable one at a time dispensing and which
 ensures that the wet wipes do not become overly dry. For example, the wet
 wipes may be arranged in the container 20 as a plurality of individual
 sheets arranged in a stacked configuration to provide a stack of wet wipes
 which may or may not be individually folded. The wet wipes may be
 individual wet wipes which are folded in a c-fold or z-fold configuration
 as are known to those skilled in the art and then stacked on top of each
 other to provide the stack of wet wipes. Alternatively, if the wet wipes
 are to be arranged in a stacked configuration in the container 20, the
 individual wet wipes may be interfolded such that the leading and trailing
 end edges of successive wipes in the stacked configuration overlap. In
 such a configuration, the leading end edge of the trailing wet wipe is
 loosened from the stack by the trailing end edge of the leading wet wipe
 as the leading wet wipe is removed by the user. The wet wipes may be
 interfolded to facilitate such dispensing by means known to those skilled
 in the art.
 Alternatively, the wet wipes may be arranged in the container 20 as a
 continuous web of interconnected wet wipes which are folded in an
 accordion-like stacked configuration. The individual wet wipes may be
 connected together along lines of frangibility, such as lines of
 perforations, to ensure that the trailing wet wipe is in position for
 grasping by the user after the leading wet wipe is removed. For example,
 the wet wipes may be provided by a continuous web of material which has a
 series of lines of frangibility extending across the width of the web. The
 portion of the web of material between successive lines of frangibility
 provides each individual wet wipe. The lines of frangibility may be
 provided by means known to those skilled in the art such as perforations,
 indentations or cuts in the web of material. For example, the lines of
 frangibility or perforations may be provided in the web of material by
 passing the web of material between a die cutter roll and anvil roll.
 After the lines of frangibility have been incorporated into the web of
 material, the web may then be arranged in a stacked configuration for easy
 insertion into the interior 38 of the container 20.
 The wet wipe container 20 of the present invention can comprise any
 suitable number of individual wet wipes depending upon the desired
 packaging and end use. For example, the container 20 may be configured to
 include a stack of wet wipes which may include at least about 5 wet wipes
 and desirably from about 16 to about 320 individually wet wipes.
 Each wet wipe is generally rectangular in shape and defines a pair of
 opposite side edges and a pair of opposite end edges which may be referred
 to as a leading end edge and a trailing end edge. The leading end edge of
 each wet wipe is typically positioned in the container 20 to be grasped by
 a user to facilitate a removal of the wet wipe from the container 20. Each
 wet wipe defines an unfolded width and an unfolded length. The wet wipe
 may have any suitable unfolded width and length. For example, the wet wipe
 may have an unfolded length of from about 2.0 to about 80.0 centimeters
 and desirably from about 10.0 to about 25.0 centimeters and an unfolded
 width of from about 2.0 to about 80.0 centimeters and desirably from about
 10.0 to about 45.0 centimeters.
 Materials suitable for the wet wipes of the present invention are well
 known to those skilled in the art. The wet wipes can be made from any
 material suitable for use as a moist wipe, including meltblown, coform,
 air-laid, bonded-carded web materials, hydroentangled materials and the
 like and can comprise synthetic or natural fibers or combinations thereof.
 The wet wipes may have a basis weight of from about 25 to about 120 grams
 per square meter and desirably from about 40 to about 90 grams per square
 meter.
 In a particular aspect, the wet wipes may comprise a coform basesheet of
 polymeric microfibers and cellulosic fibers having a basis weight of from
 about 60 to about 80 grams per square meter and desirably about 75 grams
 per square meter. Such coform basesheets are manufactured generally as
 described in U.S. Pat. No. 4,100,324 to Anderson et al. which issued Jul.
 11, 1978, and which is herein incorporated by reference. Typically, such
 coform basesheets comprise a gas-formed matrix of thermoplastic polymeric
 meltblown microfibers, such as, for example, polypropylene microfibers,
 and cellulosic fibers, such as, for example, wood pulp fibers. The
 relative percentages of the polymeric microfibers and cellulosic fibers in
 the coform basesheet can vary over a wide range depending on the desired
 characteristics of the wet wipes. For example, the coform basesheet may
 comprise from about 20 to about 100 weight percent, desirably from about
 20 to about 60 weight percent, and more desirably from about 30 to about
 40 weight percent of polymeric microfibers based on the dry weight of the
 coform basesheet being used to provide the wet wipes.
 The wet wipes of the different aspects of the present invention contain a
 liquid which can be any solution which can be absorbed into the wet wipes.
 The liquid contained within the wet wipes may include any suitable
 components which provide the desired wiping properties. For example, the
 components may include water, emollients, surfactants, preservatives,
 chelating agents, pH buffers or combinations thereof. The liquid may also
 contain lotions, ointments and/or medicaments.
 The amount of liquid contained within each wet wipe may vary depending upon
 the type of material being used to provide the wet wipe, the type of
 liquid being used, the type of container being used to store the stack of
 wet wipes, and the desired end use of the wet wipe. Generally, each wet
 wipe can contain from about 150 to about 600 weight percent and desirably
 from about 250 to about 450weight percent liquid based on the dry weight
 of the wipe for improved wiping. In a particular aspect wherein the wet
 wipe is made from a coform material comprising from about 30 to about 40
 weight percent polymeric microfibers based on the dry weight of the wipe,
 the amount of liquid contained within the wet wipe is from about 300 to
 about 400 weight percent and desirably about 330 weight percent based on
 the dry weight of the wet wipe. If the amount of liquid is less than the
 above-identified range, the wet wipes may be too dry and may not
 adequately perform. If the amount of liquid is greater than the
 above-identified range, the wet wipes may be oversaturated and soggy and
 the liquid may pool in the bottom of the container.
 As illustrated in FIGS. 1-8, the wet wipe container 20 includes a container
 base 22 that defines a bottom 28 that is connected to a front wall 30, a
 rear wall 32, and a pair of opposed side walls 34 and 36. The front, rear
 and side walls extend upwardly from the bottom 28 in a generally
 perpendicular manner to form a rectangular container base 22. The
 container base 22 can also have a trapezoidal shape. The bottom and front,
 rear and side walls of the container base 22 generally define an open
 interior 38 for containing the wet wipes. The wet wipe container 20 also
 includes a container lid 24 that defines a top 40 that is connected to a
 front wall 42, a rear wall 44 and a pair of opposed side walls 46 and 48.
 The front, rear and side walls extend downwardly from the top 40 in a
 generally perpendicular manner to form a rectangular container lid 24.
 The container base 22 and container lid 24 of the container 20 may be
 provided by a variety of materials that are inexpensive and capable of
 retaining liquids. Suitable materials include polypropylene, polyethylene,
 polystyrene and the like or combinations thereof. For example, the
 container base 22 may be fabricated from a polystyrene material having a
 thickness of from about 0.010 inches to about 0.080 inches. The container
 lid 24 may be fabricated from a combination of a styrene-butadiene-styrene
 copolymer with a polystyrene material having a thickness of from about
 0.005 inches to about 0.060 inches.
 The walls 30, 32, 34 and 36 of the container base 22 may be integral with
 the bottom 28 or may include separate members that are connected or joined
 to the bottom 28 to provide the container base 22. Similarly, the walls
 42, 44, 46 and 48 of the container lid 24 may also be integral with the
 top 40 or may include separate members that are connected or joined to the
 top 40 to provide the container lid 24. Desirably, the connections or
 corners between the walls and the top 40 and bottom 28 of the base 22 and
 lid 24 are curvilinear to provide a more aesthetically pleasing container
 20.
 The different components of the container 20 may be provided by
 conventional techniques such as thermoforming or injection molding as they
 are known to those of skill in the art. With respect to the containers of
 the invention, in some embodiments the container base 22 and container lid
 24 are provided as integral units. In some cases, injection molding
 techniques can be used to form the integral units. When the container base
 22 and container lid 24 are separate components, thermoforming techniques
 typically are used.
 In an embodiment of the containers of the invention, the container 20
 includes a container base 22 and a container lid 24 as described herein.
 In addition to a top 40 and front wall 42, rear wall 44 and side walls 46,
 48, the container lid 24 can also include a downwardly extending guide
 ridge 50. The guide ridge 50 generally is parallel to the rear wall 44 of
 the container lid 24. The guide ridge 50 is generally located close to or
 proximate the rear wall 44. The rear wall 32 of the container base 22 has
 an upper portion 52. The upper portion 52 is the uppermost portion of the
 rear wall 32 and, therefore, the portion of the rear wall 32 that comes in
 closest contact with the container lid 24. The upper portion 52 extends
 along the full length of the rear wall 32. The upper portion 52 defines a
 receiving edge 54. The receiving edge 54 is configured to receive the
 guide ridge 50 of the container lid 24. For example, the receiving edge 54
 can be arc-shaped to receive the guide ridge 50. The receiving edge 54
 receives the guide ridge 50 as the container lid 24 is closed upon the
 container base 22.
 In one embodiment of the invention, as the container lid 24 is rotated
 downward toward a closed position, the guide ridge 50 comes into contact
 with the receiving edge 54 and the receiving edge 54 urges the guide ridge
 50 downward and ahead of the receiving edge 54. Therefore, the guide ridge
 50 is spaced sufficiently away from the rear wall 44 to be able to land in
 front of the receiving edge 54 when the container lid 24 is closed on the
 container base 22. Because the guide ridge 50 extends downward from the
 top 40 of the container lid 24, the guide ridge 50 can be described as
 having a "depth" as opposed to a height. The depth of the guide ridge 50
 is sufficient to extend below the lowest point or bottom of the receiving
 edge 54. The combination of the guide ridge 50 and the receiving edge 54
 increases the ease with which the container lid 24 can be closed on the
 container base 22. Further, the guide ridge 50/receiving edge 54
 combination assists with the alignment of the container lid 24 onto the
 container base 22 for purposes of providing a secure closed position.
 Because the container lid 24 and the container base 22 are aligned
 properly, the container lid 24 can completely cover the container base 22
 and there is a reduced likelihood that the container lid 24 will "pop" off
 the container base 22. If the container lid 24 becomes partially or
 entirely detached from the container base 22, moisture will be lost from
 the wet wipe product stored in the container 20. As a consequence, the wet
 wipe product loses its ability to perform its intended function.
 The combination of the guide ridge 50 and the receiving edge 54 also
 assists with single hand use of the container 20 by permitting a partially
 open relationship between the container lid 24 and the container base 22.
 Typically, existing containers are only capable of maintaining either a
 completely open or a completely closed position. When only a low quantity
 of wet wipes remain in a container 20 and the container lid 24 is in the
 open position, the entire container 20 can tip backwards from the weight
 of the container lid 24 not being sufficiently counterbalanced. Tipping of
 the container 20 makes single hand grasping of the wet wipes difficult.
 The partially open position is achieved when the guide ridge 50 rests on
 the receiving edge 54. With containers of the invention, the difficulties
 associated with the container 20 tipping over are overcome while the user
 can still remove wet wipes from the container 20 with one hand. The
 container 20 of the invention does not tip over even when no wet wipes
 remain in the interior 38 of the container 20. Generally, when the
 container lid 24 is in the partially open position, it is approximately
 1.5 inches to 3.0 inches away from the container base 22. For at least
 these reasons, the containers of the invention are easier to use with a
 single hand and they are more stable when small numbers of wet wipes
 remain in the container 20.
 The guide ridge 50 and the receiving edge 54 can have a variety of
 configurations. Typically, the receiving edge 54 is shaped or contoured to
 at least partially complement the downward facing contour or shape of the
 guide ridge 50. While the receiving edge has a thickness, the receiving
 edge 54 is primarily two dimensional. The receiving edge 54 can extend the
 full length of the upper portion 52 of the rear wall 32 or extend only
 along part of the length of the upper portion 52. The guide ridge 50 has a
 length 51 (shown in FIG. 3), a depth 55 (depicted in FIG. 7) and a
 thickness 53 (depicted in FIG. 3). Generally, the length 51 of the guide
 ridge 50 is less than the length of the rear wall 44. The guide ridge 50
 can desirably have a ratio of the length 51 of the guide ridge 50 to the
 length of the rear wall 44 of from about 40% to about 90%. In most
 embodiments, the depth 55 of the guide ridge 50 ranges from about 0.25
 inches to about 0.75 inches. The thickness 53 of the guide ridge 50 can
 range from about 0.0625 inches to about 0.25 inches. The position of the
 guide ridge 50 against the rear wall 32 of the container base 22 when the
 container lid 24 is closed is visible in the representative cross-section
 of a container 20 end depicted in FIG. 7.
 As described herein, the containers of the invention can be manufactured
 out of polymers, copolymers or mixtures of polymers and copolymers.
 Additional components can be added to provide various functionalities to
 either the overall container 20 or the individual container base 22 and
 container lid 24. In one example, the container base 22 is formed from
 approximately 98% of a high impact polystyrene such as is available from
 Dow Chemical of Midland, Mich. as Dow SYTRON.RTM. 484. The remainder of
 the composition of the container base 22 can be an impact modifier such as
 STEREON.RTM. which is available from the Firestone Company. In an example
 of a container lid 24 of the invention, the container lid 24 is made of
 approximately 70% of a styrene-butadiene-styrene copolymer such as
 FINAPRENE.TM. Thermoplastic Elastomers, Finaclear 520 available from the
 Fina Oil and Chemical Company. The container lid 24 can also include
 approximately 20% of a general purpose polystyrene such as FINA.RTM.
 Polystyrene 524B available from the Fina Oil and Chemical Company. The
 container lid 24 can further include approximately 10% of a high impact
 polystyrene such as the Dow SYTRON.RTM. 484. If desired, the container lid
 24 can include a colorant in an amount of from about 0.08% to about 1.2%
 by weight. Suitable colorant compounds are known to those of skill in the
 art.
 One or the other of the container lid 24 and the container base 22 of the
 containers of the invention can be transparent, translucent or opaque.
 There are certain advantages associated with either of the container lid
 24 or the container base 22 being transparent or translucent. For example,
 when the container lid 24 is transparent, the user of the container 20 can
 readily determine the quantity of wet wipes remaining in the container 20.
 That is, the user can determine the quantity of wet wipes remaining in the
 container 20 without having to open the container lid 24 of the container.
 This is useful, in part, because some wet wipe products are sold without
 containers in refill packs. The consumer may make intermittent purchases
 of the wet wipes in a container 20, such as described herein but may also
 make supplemental purchases of the wet wipes in refill packs. The
 consumers may refill the container 20 with wet wipes purchased as part of
 the refill packs. When the container lid 24 and container base 22 are
 translucent, the container 20 of the invention is desirable for secondary
 uses. For example, when a consumer no longer uses the container 20 for
 holding wet wipes, the consumer may want to use the container 20 to store
 small toys, art supplies and other household items. If the container 20 is
 translucent, one can see what is inside of the container 20 without having
 to open the lid 24 or without having to relocate items that may be on top
 of or around the container 20.
 Aesthetic and functional advantages are also obtained when one or the other
 of the container lid 24 or container base 22 are colored. For example,
 differently colored containers can be used to distinguish the packaging
 for different types of wet wipe products. Similarly, aesthetic and
 functional advantages can be achieved when the container lid 24 or the
 container base 22 have graphics printed on them. In addition to aesthetic
 benefits, the graphics can be used to distinguish between various wet wipe
 product types.
 As already described herein, the container lid 24 and the container base 22
 can be formed of a single integral piece or be formed as separate pieces.
 With respect to containers of the invention that are formed from two
 separate pieces, the container lid 24 is attached or connected to the
 container base 22 using a variety of techniques known to those of skill in
 the art. In some embodiments, the container lid 24 and the container base
 22 are attached at their rear walls. The rear wall 44 of the container lid
 24 can be attached to the rear wall 32 of the container base 22 through
 the use of glues, adhesives or other bonding agents; through heat sealing;
 through ultrasonic bonding; or through the use of physical connectors such
 as pins or interlocking members.
 In another embodiment of the present invention, the container 20 includes a
 container base 22 and a separate container lid 24 that is attached to the
 container base 22. As representatively illustrated in FIGS. 6-8, the rear
 wall 44 of the container lid 24 has an outwardly extending flange 60. The
 outwardly extending flange 60 is generally two-dimensional and the flange
 60 has a width 61 and a length 63. The outwardly extending flange 60
 extends away from the plane of the rear wall 44 in a primarily
 perpendicular direction. The flange 60 includes three general areas: the
 area nearest the rear wall 44, that is, the immediately adjacent area 66;
 the hinge channel 64; and the attachment area 62. The attachment area 62
 is located furthest away from the rear wall and the hinge channel 64 is
 centrally located between the immediately adjacent area 66 and the
 attachment area 62. Each of the three areas or sections of the flange 60
 is primarily linear in shape and each area has an individual length, width
 and thickness. The three areas are generally parallel to each other and
 extend in a direction that is primarily parallel to the rear wall 44 of
 the container lid 24. The rear wall 32 of the container base 22 has a top
 or upper portion 52 that runs linearly along the portion of the rear wall
 32 that is furthest away from the bottom 28. The top portion 52 has an
 outwardly extending lip 70. The outwardly extending lip 70 is generally
 planar and extends away from the top portion 52 in a direction that is
 primarily perpendicular. The container lid 24 is attached to the container
 base 22 by attachment of the flange 60 to the outwardly extending lip 70.
 More specifically, the attachment area 62 of the flange 60 is attached to
 the outwardly extending lip 70. Therefore, in general terms, the container
 lid 24 and the container base 22 are attached to each other along their
 rear walls. The attachment area 62 and the outwardly extending lip can be
 attached to each other using any of the techniques generally known to
 those of skill in the art. One example of a suitable technique is
 ultrasonic bonding.
 In one embodiment of the invention, the end edges of the flange 60 can be
 tapered. The tapering of the flange 60 ends results in the ends of the
 flange 60 being curved. When an end of the flange 60 has a curvilinear
 shape, the end forms an angle 69, depicted in FIG. 8, away from the rear
 wall 44 that is less than ninety degrees. In conventional containers, the
 edge of the hinge between the container lid and container base can be
 perpendicular, or at ninety degrees, with the back panel of the container
 lid. Provision of a curvilinear shape and angle of less than ninety
 degrees provides several advantages to the container 20. Curvature of the
 end edges of the flange 60 gives a more user-friendly container 20 in that
 the flange 60 is less likely to catch on fabric or skin. When the flange
 60 edges are tapered along a curve, the immediately adjacent area 66 has
 the greatest length and the attachment area 62 has the smallest length.
 While the length of the flange 60 does not typically exceed the length of
 the rear wall 44, the lengths of the three areas can vary depending on
 whether and how the tapering is executed. For example, in a particular
 embodiment, the length of the hinge channel 64 can be from about 60% to
 about 85% of the length of the rear wall 44. The length of the attachment
 area 62 can be from about 50% to about 75% of the length of the rear wall
 44.
 In an additional embodiment of the invention, the hinge channel 64 has two
 ends, each end of the hinge channel 64 including an end region 68. The
 hinge channel 64 has a primary thickness and the end regions 68 have a
 secondary thickness. The secondary thickness of the end regions 68 is
 generally greater than the primary thickness of the hinge channel 64. For
 example, the primary thickness of the hinge channel 64 can be from about
 0.005 inches to about 0.015 inches. The secondary thickness of the end
 regions 68 is from about 20% to about 100% greater than the primary
 thickness. In a similar embodiment, the overall thickness of the outwardly
 extending flange 60 varies along the width of the flange 60. As with the
 tapered flange 60 length described herein, the thickness of the flange 60
 can have a gradual change across the three areas of the flange 60. An
 example of the gradual change or tapering of the thickness of the flange
 60 is depicted in FIG. 8.
 In one example of a flange 60 of the invention, the immediately adjacent
 area 66 has an initial thickness 73 of about 0.040 inches at the point
 nearest the rear wall 44. The end region 68 of the hinge channel 64 has a
 thickness 65 of about 0.015 inches; the remainder of the hinge channel 64
 has a thickness 67 of about 0.009 inches. The thickness of the flange 60
 can then increase over the transition from the end region 68 or hinge
 channel 64 to the attachment area 62. The attachment area 62 is shown in
 FIGS. 8A and 8B as having a thickness 71 that is approximately the same as
 the thickness 73 of the immediately adjacent area 66, however the
 thicknesses 71 and 73 can be different. As shown in FIG. 8A, the thickness
 73 of the flange 60 in the immediately adjacent area 66 can gradually thin
 from about 0.040 inches to about 0.015 inches, the thickness 65 of the end
 region 68. The thickness 65 of the flange 60 can remain fairly constant
 over the width of the end region 68. On the other side of the end region
 68, the thickness 71 of the flange 60 would gradually increase across the
 width of the attachment area 62 until the thickness 71 reached a value of
 about 0.040 inches. The variation in the thickness 73 of the immediately
 adjacent area 66, the thickness 67 of the hinge channel 64 and the
 thickness 71 of the attachment area 62 over the width of the flange 60 is
 depicted generally in FIG. 8B.
 With the containers of the invention, performance benefits are seen with a
 container lid 24 having an outwardly extending flange 60 from the rear
 wall 44 where the flange 60 has a hinge channel 64 with an end region 68
 of a greater secondary thickness 65. When the hinge channel 64 has an end
 region 68 of a secondary thickness 65, the hinge channel 64 is more
 resistant to tearing. The hinged areas of conventional containers
 typically are susceptible to tearing after repeated use. Apparently, the
 hinge becomes strained over time to the point of tearing from the repeated
 opening and closing of the lid. In order to demonstrate the improved tear
 resistance of the containers of the invention, the apparatus depicted in
 FIGS. 9 and 10 was constructed to simulate repetitive opening and closing
 of a container lid 24. A representation of a flex test instrument 80 is
 shown in FIGS. 9 and 10. The flex test instrument 80 can simulate
 container lid 24 motion on two containers 20 at a time. The flex test
 instrument 80 includes a motor assembly 82 that is housed approximately in
 the center of the instrument platform 90. The motor art assembly 82
 includes a gear motor, motor controller and miter gear. Suitable motor
 assembly 82 components can be purchased by part number from the following
 manufacturers: (1) Gear Motor--W. W. Grainger, Part #4Z539; (2) Motor
 Controller--W. W. Grainger, Part #4Z527; and (3) Miter Gear--W. M. Berg,
 Part #MX-3-D. The motor assembly 82 drives rotating motion arm 84 through
 a range of motion that emulates the range of motion experienced by a
 container lid 24 from repeated opening and closing. Relative to the
 vertical plane, the rotating motion arm 84 moves over a range of from
 about -78.degree. to about +78.degree.. Each cycle of the rotating motion
 arm 84 is detected and recorded by a counter 92. A suitable counter 92 is
 part number H7CS-B of the Omron Corporation of Japan, or an equivalent.
 FIG. 9 shows operation of the flex test instrument 80 when the container
 lids 24 are in a virtually closed position and FIG. 10 shows the flex test
 instrument 80 when the container lids 24 are in an open position. In
 setting up the flex test instrument 80 to perform a test, the containers
 20 are placed on the platform 90 of the instrument 80. The containers are
 placed between two spacer bars, one in front of the container 20 and one
 behind the container 20. The rear spacer bars are not visible in the
 figures. The front spacer bar is an adjustable spacer bar 88 and can be
 moved rearwardly through rotation of a knob 94 until a position is
 achieved that firmly holds the container 20 on the platform 90. Each
 branch of the rotating motion arm 84 terminates with a slotted end 86. The
 slotted end 86 slides over and clips to a portion of the front wall 42 of
 the container lid 24. In order to demonstrate the improved tear resistance
 associated with the containers of the invention, comparative tests were
 conducted between a conventional container and a container 20 of the
 invention using the flex test instrument 80. To represent a conventional
 container, a HUGGIES NATURAL CARE.RTM. container was tested. The container
 20 of the invention had a separate container lid 24 with an outwardly
 extending flange 60. The outwardly extending flange 60 included a hinge
 channel 64 having a primary thickness 67, the hinge channel 64 having an
 end region 68 of a greater secondary thickness 65. The primary thickness
 67 was about 0.009 inches and the secondary thickness 65 was about 0.015
 inches. The flex test instrument 80 was operated at about 50 cycles/min.
 The conventional HUGGIES NATURAL CARE.RTM. container experienced tearing
 across the entire length of the hinged area after about 9,000 cycles. The
 representative container 20 of the invention experienced no tearing of the
 hinge channel 64 after about 28,000 cycles.
 The present invention is also directed to a wet wipe container 20 having a
 container lid 24 that is connected to a container base 22 and a closure 56
 that is configured to releasably hold the container lid 24 on the
 container base 22 in a closed position. As illustrated in FIGS. 1-8, the
 container lid 24 is hingedly connected to the container base 22. The
 container base 22 includes a front wall 30 that extends upward from a
 bottom 28. The front wall 30 has a top surface 72. The top surface 72 is
 in a position that is furthest away on the front wall 30 from the bottom
 28. The closure 56 includes an upright tongue projection 58 that is
 continuous with and extends upward from the top surface 72. The tongue
 projection 58 has curved edges and is generally semi-circular in
 configuration. The tongue projection 58 is of a length suitable for
 gripping. The tongue projection 58 includes a flattened grip area 74. The
 flattened grip area 74 is approximately of a length that can be easily
 pushed against by a full size human finger or thumb. The flattened grip
 area 74 is generally located in the center of the tongue projection 58 and
 may have a width that is greater than the width of the tongue projection
 58. The larger width of the grip area 74 can create a flat surface on the
 top of the tongue projection 58 for improved performance.
 The top surface 72 may also include an arcuate depression 76 that is
 located primarily below the flattened grip area 74 of the tongue
 projection 58. In addition to the tongue projection 58 and the arcuate
 depression 76, the top surface may further include an assistive region 78.
 The assistive region 78 is positioned below the arcuate depression 76 and
 has a shape that is generally concentric, and therefore semi-circular,
 with the configuration of the tongue projection 58. The rise of the
 semi-circular assistive region 78 approaches but does not need to touch
 the arcuate depression 76. The closure 56 also includes an aperture 98.
 The aperture 98 is formed within the front wall 42 of the container lid
 24. The front wall 42 has a convex portion 96 that extends somewhat
 outward and away from the front wall 42 in a perpendicularly-oriented
 direction. The aperture 98 is long enough to accommodate the length of the
 tongue projection 58. When the container 20 is in a closed position, the
 tongue projection 58 extends upward through the aperture 98. In another
 embodiment, the tongue projection 58 could extend downward from the front
 wall 42 of the container lid 42 and the aperture 98 could be located
 within the top surface 72 of the front wall 30 of the container base 22.
 Either of the container lid 24 and the container base 22 can be transparent
 or translucent. Further, either of the container lid 24 and the container
 base 22 can be colored. In some applications, it is desirable to have the
 container lid 24 be of a different color than the container base 22. If
 the container lid 24 is colored, the aperture 98 is more visible and the
 container 20 is easier to close. It is also easier to determine that the
 container 20 is securely closed when the components of the closure 56 have
 different colors.
 The closure 26 provides a more user-friendly and ergonomic way to open the
 container 20. The closure 26 of the invention provides for single hand
 opening and closing of the container 20. Single hand container opening is
 important for some wet wipe applications such as for diapering of a young
 child. In the case of baby wipes, often times a parent must use one hand
 to hold the child while changing a diaper and then must use their other
 hand to pick up a wipe for cleaning. If the parent does not open the wipe
 container 20 before beginning the diaper changing process, then they must
 do it single handedly while changing the diaper. The baby wipe container
 20 of the invention is very easily opened with one hand. In one method of
 opening the container 20, one or two fingers can be placed on top of the
 tongue projection 58 while the thumb is placed under the convex portion 96
 of the container lid 24 and against the assistive region 78. With the
 fingers in this type of arrangement on the closure 26, the thumb can push
 against the assistive region 78 to raise the container lid 24 up and over
 the flattened grip area 74. The guide ridge 50 located on the underside of
 the top 40 of the container lid 24 maintains the container lid 24 in a
 partially open position. The partially open position of the container lid
 24 prevents the container 20 from tipping over if a small number of wipes
 remain in the container 20.
 In another embodiment, the present invention relates to a wet wipe
 container 20 that has a container base 22 and a container lid 24 that is
 connected to the container base 22. The container base 22 includes a
 bottom 28 and a front wall 30, rear wall 32 and a pair of opposed side
 walls 34, 36. The walls extend upward from the bottom 28 in a generally
 rectangular configuration to provide an interior 38 for containing the wet
 wipes. The walls may have one or more generally linear ribs 100 formed
 into the walls. The ribs 100 can be linear or slightly curved. The spacing
 between the ribs 100 can vary and the ribs 100 can be oriented either
 horizontally or vertically.
 The ribs 100 provide several benefits including a more aesthetically
 appealing appearance and a container base 22 that can be more easily
 gripped and handled. The ribs 100 make it easier to pick up and hold the
 container 20. Another benefit of the ribs 100 is that the ribs 100
 substantially improve the compression strength of the container 20. During
 shipping and storage and even during display, containers are stacked
 vertically on top of each other. Depending on how many containers are
 stacked, a given container 20 experiences some amount of vertical
 compression force. Conventional containers are susceptible to crushing and
 buckling when they have a quantity of containers stacked on top of them.
 Conventional container lids become crushed in a downward direction and the
 container bases buckle from the vertical force. The presence of ribs 100
 formed into one or more walls of the container base 22 gives the container
 20 overall better resistance to compressive forces. Therefore, the
 containers 20 of the invention experience less crushing and are more
 resistant to buckling. The ribs 100 can vary in length and can be of
 varying length within a given wall.
 Accordingly, the different aspects of the present invention can
 advantageously provide containers for wet wipes which, when compared to
 conventional containers for wet wipes, provide improved single handed
 opening and dispensing. Such containers are particularly useful for
 dispensing baby wipes since the care giver typically only has one hand
 free during the diapering process. Thus, the containers for wet wipes of
 the present invention are reliably and easily opened by one hand of the
 user or care giver for improved convenience and personal hygiene.
 Additionally, the containers of the invention can maintain a partially
 open position of the container lid and provide better alignment between
 the container lid and the container base. The container lids of the
 invention are also more tear resistant and are less likely to fail upon
 repeated opening and closing of the lid. Further, the containers of the
 invention have improved compression strength and are more difficult to
 crush.
 While the invention has been described in detail with respect to the
 specific aspects thereof, it will be appreciated that those skilled in the
 art, upon attaining an understanding of the foregoing, may readily
 conceive of alterations to, variations of, and equivalents to these
 aspects. Accordingly, the scope of the present invention should be
 assessed as that of the appended claims and any equivalents thereto.