The present invention pertains to a magnetic closure system for containers that have a wand-type applicator and wiper, but no screw threads.
Many cosmetic and personal care products are sold in containers that use a threaded or screw-type closure system. Containers that use a lug style closure system also require the closure to rotate relative to the container in order to effect a tight seal. More specifically, when it comes to containers that use a wiper and a wand-type applicator (for example, containers for mascara, lip gloss, and eye shadow) the screw-type, rotating closure system dominates the market. A wiper placed in the neck of a container is generally designed to make a tight seal against the neck. A flange of the wiper lays on top of the landing area of the container. As the closure and container are drawn together through their relative rotation, the closure pushes down on the wiper, and compresses the wiper against the landing area of the container. When the packaging is executed properly, this compression creates an effective seal to protect the product. Typically, the closure rotation stops, and the closure is fully mounted on the container when the wiper cannot be compressed further. This event is generally silent, and is of little or no interest to a user. Furthermore, to create an effective seal, a substantial amount of effort is required every time the container is closed. If twisted to tightly, the closure may be difficult to loosen. For some people, the effort required to effect the relative rotation of the container and closure may be substantial or impossible. These are problems that cry out to be rectified.
A main object of the invention is to provide an effective alternative to screw-type closures for containers that use a wiper and a wand-type applicator.
For products that use a wand and wiper, another object is to provide a closure-container system that is easier to open, and easier to close while maintaining an effective seal.
Another object is to make dull, wand-type applicators a thing of the past by providing a luxury experience to consumers.
The present challenges are met by a container and closure as described herein. A container (1) (with or without screw threads) comprises a custom wiper (3) that sits in the neck of the container, and one or more magnetic elements (2) that encircle the neck of the container. A closure (5) comprises an overshell (8) that supports a handle (5b) and one or more ferromagnetic elements (6). A conic section (5g) depends from the handle, and a wand (5d) depends from the conic section. The wand supports an application surface (4) on its distal end.
As a user inserts the application surface and wand into the container through the wiper, the magnetic elements (2) attract the ferromagnetic elements (6) until the magnetic and ferromagnetic elements make contact, or until they are a predetermined distance apart. The result is a satisfying, reassuring metallic “click” sound, accompanied by a luxurious tactile sensation. The strength of the magnetic elements (2) for the ferromagnetic elements (6) is sufficient to effect a tight seal in two sealing zones: between the conic section (5g) of the closure and the beveled surface (3g) of the wiper (3); and between the bottom (5a) of the handle and the custom sealing lip (3a) on the top of the wiper. To open the container, a user merely has to pull the container and closure apart, preferably by tilting the closure in relation to the container, so that some of the contact between the magnetic and ferromagnetic elements is reduced.
One or more magnetic elements are associated with the container (1), in the area around the neck (1b). The magnetic element(s) must be securely attached to neck and able to interact with one or more ferromagnetic elements (6) of the overshell (8). Thus it is preferable if the one or more magnetic elements are positioned close to the top of the neck, near the landing area (1f), and preferably distributed around the circumference of the neck (1b). In the preferred embodiment shown in
In some preferred embodiments, the one or more magnetic elements (2) are metallic. For the ring magnet shown in the
Examples of potentially useful magnets include hard ferrite magnets, which are cost effective; AlNiCo (aluminum-nickel-cobalt) magnets, which are permanent metallic magnets; SmCo (samarium-cobalt) magnets, which are permanent metallic rare earth magnets. One preferred magnet is a ring of NdFeB (neodymium-iron-boron), having a magnetization grade of N45, and having a preferred internal diameter of 12 mm, and preferred external diameter of 14 mm, a preferred height of 14.5 mm. Of course depending of the packaging design these dimensions can be adjusted. N45 is a standard neodymium-iron-boron grade for which the maximum energy product (BHmax) ranges from 43 to 46 MGOe (megaGause-Oersteds; 1 MGOe is approximately equal to 7957.74715 J/m3). Useful magnets of invention may have a maximum energy product in the range of about 10 to about 100 MGOe, preferably about 25 to about 75 MGOe, more preferably about 40 to about 50 MGOe. However, the magnetic field experienced by the one or more ferromagnetic elements (6) in the overshell (8) will also depend on the shape and mass of the magnet. Some potentially useful magnets will have an axial magnetization and a mas off about 100 grams to about 1000 grams.
Referring to
Up to now, we have described features of a conventional wiper, which may be suitable for some embodiments of the invention. However, when airtight sealing of the container (1) must be guaranteed, it is preferable to use a custom wiper, as now described. In a custom wiper according to the present invention, the upper opening (3e) is surrounded by a beveled surface (3g). Furthermore, where the beveled surface meets the flange (3f), a sealing lip (3a) extends upwardly and outwardly from the beveled surface. In some preferred embodiments of the invention, the sealing lip is formed as a flat flap that encircles the upper opening (3e) of the wiper. The beveled surface (3g) and sealing lip (3a) interact with a custom closure (5) to form an effective airtight seal. Preferably, the beveled surface (3g) and the sealing lip (3a) are molded from relatively flexible thermoplastic elastomers, such as polyurethanes or polyesters having a Shore hardness less than about 50. This flexibility improves the airtightness in the sealing zones of the beveled surface and sealing lip. It is also preferable for the lower opening (3d) to be molded from relatively flexible thermoplastic elastomers. This is because molded brushes generally require a wiper orifice that is molded from flexible material to avoid any damage to the molded bristles during the wiping.
The custom wiper (3) of
Referring to
The handle (5b) will generally be large enough to be comfortably gasped in the hand of a user. Handles for wand-type applicators are typically cylindrical, from about 10 to about 30 mm in diameter. Usually the diameter of the handle is chosen to match the diameter of the container, although this is not required. The length of the handle may typically range from about 20 mm to about 50 mm, but longer handles are also known. An overshell (8) is provided to give the handle (5b) a finished appearance, and to secure one or more ferromagnetic elements around the handle. The overshell fits snuggly over the handle, so that the handle cannot back out of the overshell, in normal use. The handle may be provided with ridges (5c, as shown in
Referring to
The conic section (5g) depends from the handle (5b). The angle of the conic section is steeper than the angle of the beveled surface (3g, 9g-12g)) of the wiper (3, 9-12). However, when the closure (5) is fully seated on the container (1), then the conic section (5g) of the closure (5) contacts the beveled surface of the wiper, causing the beveled surface to flex to more nearly match the angle of the conic section, and a sealing engagement is effected 360° around the beveled surface. To ensure good contact between the conic section (5g) and the beveled surface (3g), the diameter of the conic section, at the level where the conic section contacts the beveled surface, should be slightly larger than the diameter of the beveled surface. Generally the conic section and beveled surface will have an interference from about 0.1 mm to 0.25 mm, preferably about 0.15 mm. This interference provides one seal against leakage. In a package with a threaded closure mechanism, this interference seal would typically be sufficient to prevent leakage. However, since the present package does not use a threaded closure mechanism, a second sealing zone is provided in the form of a sealing lip (3a, 9a-12a) that encircles the upper opening (3e, 9e-12e) of the wiper (3, 9-12).
The wand (5d) depends from the conic section and supports an application surface (4) on its distal end. In
As noted, the compression of the sealing lip (3a, 9a-12a) by the handle (5b), as effected by the magnetic attraction of the ring magnet (2) for the steel ring (6), is sufficient to make a second effective seal. By “effective seal” we mean sufficiently air tight and water tight for commercial purposes. In fact, depending on the magnet material used, it may be necessary to include a plastic ring (7) to attenuate some of the force of magnetic attraction. If the handle is held on the container too strongly by the magnet, then a user may find it difficult to remove the application surface (4) from the container. When the available magnet is too strong, this situation may be alleviated by placing plastic ring (7) in between the ring magnet (2) and the steel ring (6). The plastic ring may be glued into the overshell (8) or directly onto the steel ring. The plastic ring is shown in
In addition to an effective seal in a non-screw threaded closure system, the force of attraction between the ring magnet (2) and the steel ring (6) is sufficient to make an audible clicking noise when the two elements make contact. As the wand-type applicator is inserted into the container, suddenly the applicator is pulled along by a “magical” force, and it clicks into place. The sound is satisfying and reassuring, and provides the user with a luxury experience. Thus, it is preferable if the ring magnet (2) and the steel ring (6) are able to make solid contact with a force that is sufficient to make an audible clicking noise. But even when a plastic ring (7) is disposed between the two, a sound that acknowledges closure of the container may still be heard.