EP1993926B1

EP1993926B1 - Vacuum storage container

Info

Publication number: EP1993926B1
Application number: EP07757905A
Authority: EP
Inventors: Carl L. Bergman; Ryan J. Coonce
Original assignee: Glad Products Co
Current assignee: Glad Products Co
Priority date: 2006-03-14
Filing date: 2007-03-05
Publication date: 2011-05-11
Anticipated expiration: 2027-03-05
Also published as: EP1993926A4; KR20090004924A; MX2008011708A; ES2363564T3; CN101432206A; WO2007106676A3; EP1993926A2; WO2007106676A2; AU2007226721A1; CA2645421A1; JP2009530193A; US20100200588A1; ZA200807819B

Abstract

A thin-walled vacuum storage container made of a plastic material may have a base providing a storage cavity and a detachable lid connectable to the base for covering the storage cavity. To evacuate the storage cavity, the container also includes a valve element communicating with the storage cavity and that may be adapted to interface with a vacuum device. The base and/or the lid can have at least one wall made by a thin-wall manufacturing process wherein the wall thickness is about 2.5 millimeters or less. Alternately, the base and/or lid can have at least one wall with a flow-length-to-wall-thickness ratio of about 90: 1 or greater.

Description

BACKGROUND

A variety of different containers are available for storing and preserving food items for later consumption. Such containers may be flexible, as in the case of plastic storage bags, or may be rigid, as in the case of plastic and glass-walled storage containers. An advantage of rigid storage containers is that they can maintain their shape and thereby protect the stored food items from being crushed. Another advantage is that rigid containers are usually easily washable and therefore can be reusable. Also, it is desirable that rigid containers be temperature and microwave resistant to allow for heating, cooling and freezing of the stored food items within the container. To accomplish these advantages, rigid containers are often made as a relatively thick-walled structure of a stiff material such as Pyrex™ glassware or polycarbonate plastic. Such I materials, in addition to being relatively heavy, are also costly.
To preserve the food items within the storage container, it is desirable to minimize their contact with air that can dehydrate and spoil the food items, Accordingly, thick-walled rigid containers are typically made to effect a sufficient air-tight seal. It is also desirable to reduce the quantity of air that may become trapped within the container during storage. Such trapped air can be removed by "burping" or, in other words, depressing the lid of a thick-walled, rigid container into the storage cavity of the container to displace air trapped therein. To maintain and withstand the vacuum conditions and to facilitate the above mentioned advantages, rigid vacuum storage containers are made with dense material and substantial wall thicknesses, all of which adds additional costs to the storage container.
The documents US 5,974,686 , EP 0 524 551 A1 , US 3,854,618 and DE 103 48 119 disclose a variety of different containers for storing and preserving food items.

BRIEF SUMMARY OF THE INVENTION

The invention provides a rigid storage container according to claim 1. To remove air that may become trapped in the container after the base and lid have been connected, the container includes a valve element that communicates with the storage cavity. A valve element can interface with a vacuum device to remove air from the storage cavity, thereby placing the contents under a vacuum environment. When not interfaced with the vacuum device, the valve element normally seals the storage cavity to prevent the ingress of air. To reduce weight and cost, the base and lid of the container can be substantially formed with generally rigid thin-walls made of a suitable plastic material.
Production of the thin-walls can be accomplished by any of the various suitable thin-walled manufacturing techniques, such as thin-walled injection molding. Such manufacturing techniques can produce parts having a thin-walled thickness of about 2.5 millimeters or less. Another characteristic of parts manufactured by thin-walled techniques is that such parts can have a flow-length-to-wall-thickness ratio of about 90 to 1 or greater. A flow-length-to-wall-thickness ratio compares the distance which plastic material must displace or move within a mold with the wall thickness of the molded part.
An advantage of thin-walled vacuum storage containers is that they are generally light-weight and inexpensive as compared to prior art containers. Another advantage is that thin-walled containers are sufficiently rigid to be washable and therefore reusable. These and other advantages and features of the thin-walled vacuum storage containers will be apparent from the following drawings and detailed description of the embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is an exploded view of a thin-walled vacuum storage container including a base and a lid with a valve element and also showing the nozzle of a vacuum device for producing a vacuum within the container.
Figure 2 is a perspective view of a vacuum storage container interfacing with the vacuum device.
Figure 3 is a cross-sectional view taken through the storage container along line 3-3 of Figure 2 showing the valve element and the base-lid connection.
Figure 4 is a detailed view of the indicated area in Figure 3 which is labeled Figure 4 showing in better detail the base-lid connection.
Figure 5 is a perspective view of the storage container with the storage cavity appropriately evacuated.
Figure 6 is a cross-sectional view of the evacuated storage container of Figure 5.
Figure 7 is a perspective view of the vacuum storage container according to the invention having a feature in the form of projecting embossments for protecting the valve element.
Figure 8 is an elevational cross-sectional view taken through the storage container of Figure 7 along line 8-8 and showing multiple storage containers in a stacked relationship.
Figure 9 is a perspective view of a vacuum storage container having a feature in the form of projecting fingers for protecting the valve element.
Figure 10 is a partially exploded perspective view of another vacuum storage container showing another type of valve element, particularly a duck-bill valve element, and the nozzle of a vacuum device.
Figure 11 is a cross-sectional view taken through the storage container of Figure 10 along line 11-11.
Figure 12 is a cross-sectional view similar to Figure 3 and Figure 11 taken of a storage container showing another type of valve element, particularly a diaphragm valve element, in a closed state.
Figure 13 is a cross-sectional view of the storage container and diaphragm valve element of Figure 12 showing the diaphragm valve element in an open state and interfacing with the nozzle of a vacuum device.
Figure 14 is a partially exploded perspective view of the storage container of Figure 12.
Figure 15 is a perspective view of another vacuum storage container having a round or circular shape.
Figure 16 is a cross-sectional view similar to Figure 3 taken of another vacuum storage container wherein the base and detachable lid are connected by a hinge.
Figure 17 is a detailed view similar to Figure 4 taken of another vacuum storage container wherein the base and detachable lid are connected together by corresponding protrusions in a snap-fit relationship.
The only container according to the invention is the one shown in Figs. 7,8.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Now referring to the Figures, wherein like reference numbers refer to like elements, there is illustrated in FIGS. 1 and 2 the parts of a vacuum storage container 100 including a base 102 and a detachable lid 104 that can be connected to the base. To receive items for storage, the base 102 is shaped to provide a void or storage cavity 106. In the illustrated embodiment, the base 102 is rectangular and includes a flat, centrally located bottom panel 108 and four straight, generally upright side panels 110. In some embodiments, the upright side panels can actually angle slightly outward to facilitate nested stacking of multiple bases together. The space opposite the bottom panel 108 and surrounded by the top edges of the side panels 110 provides an opening 112 for accessing the storage cavity. The side edges of each of the side panels 110 are interconnected to bound the storage cavity 106, with the exception of the opening 112, and thereby provide the rectangular shape of the storage container 100. In other embodiments, however, the storage container can have any number of base panels and side panels and can have any suitable shape including cup-shaped and/or bowl-shaped. For example, referring to FIG., 15, there is illustrated a vacuum storage container 160 having a circular shaped lid 164 detachably connected to a base 162 having a circular cross-section. Because the circular side panel 168 of the base 162 tapers, the base overall is shaped as a truncated cone. In addition, the containers may be in different sizes.
To completely enclose the storage cavity 106, in the illustrated embodiment, the lid 104 is formed as another generally flat panel having a peripheral edge 114 that corresponds to the rectangular shape of the base 102. Of course, the lid can have any other suitable shape depending upon the arrangement and shape of the base. Referring to FIGS. 3 and 4, to facilitate an airtight seal between the base 102 and lid 104 when connected, the base includes an upward extending projecting tongue 116 that extends continuously about a rim established by the interconnected side panels 110. Disposed into the lid 104 continuously about the peripheral edge 114 is a U-shaped groove 118 for receiving the tongue 116 when the lid and base are connected. Improved air tightness can be realized by placing a resilient gasket 120 in the groove 118. The gasket 120 can be made of elastomeric material. Thus, when the base 102 and lid 104 are connected, the tongue 116 can press into gasket 120 with the gasket urging back against the tongue thereby creating a positive sealing effect. In one embodiment, the gasket may be compressible. In other embodiments, the gasket 120 may be eliminated, and the base 102 and lid 104 make an airtight seal, for example, by using specified tolerances, cut backs, undercuts or other techniques. In addition, the containers may also be vacuum tight.
Referring to FIGS. 1 and 2, to preserve food items stored in the storage cavity 106, there is attached to the lid 104 a valve element 122 which communicates with the storage cavity when the base and lid are connected. In the embodiment illustrated in FIGS. 1, 2, and 3, the valve element 122 is an umbrella type valve element. The umbrella type valve element 122 can be made from a flexible material, such as, rubber, and includes a circular flexible skirt 124 and a neck 126 projecting from approximately the center of the skirt. To attach the valve element 122 to the lid 104 such that the valve element communicates with the storage cavity 106, there are disposed through the center of the lid three closely-spaced holes or apertures 128 in a straight line with each other. The neck 126 is inserted into the center aperture 128 to retain the valve element 122 to the lid 104 in such a manner that the flexible skirt 124 overlays the apertures. In other embodiments, the lid may include one, two, four, five or more apertures. For example, in a one aperture embodiment, the center aperture may be used to retain the valve element and also allow the passage of air, such as, by a loose fit or by a groove in the neck of the valve element. Referring to FIG. 3, in various embodiments, to prevent contamination of the valve element 122 by contents stored within the storage container 100, a filter 129 can be fitted about valve element on the inside of the container. The filter 129 may be filter material. The filter may separate liquids and/or solid particles from the air.
To evacuate the storage cavity, referring to FIGS. 1 and 2, the valve element 122 can interface with a vacuum device. For example, a nozzle 132 of a handheld vacuum device 130 is placed adjacent the lid 104 and surrounds the valve element 122. The tip of the nozzle 132 can include a gasket 134 that can be made from a resilient material, such as, foam to ensure a good seal between the vacuum device 130 and the storage container 100. When the vacuum device 130 is activated, the flexible skirt 124 lifts upward from the lid 104 exposing the apertures 128. Hence, air trapped in the storage cavity 106 can be removed by the vacuum device 130. When the vacuum device 130 is turned off or removed from the storage container 100, the skirt 124 resiliently falls adjacent the lid 104 covering the apertures 128 and thereby preventing air from reentering the container 100. Moreover, the vacuum within the storage cavity 106 will tend to pull the flexible skirt 124 adjacent the lid 104 via the apertures 128 thereby the apertures remain sealed.
When the storage cavity 106 is under vacuum, referring to FIGS. 5 and 6, the lid 104 may be drawn or displaced partially into the storage cavity. Because the nozzle 132 of the vacuum device includes the gasket 134, a seal is maintained between the vacuum device and the storage container even as the lid 104 displaces. To release the vacuum, an individual can pry or lift the flexible skirt 124 of the valve element 122 with his or her fingers to expose the apertures 128 allowing air to enter the storage cavity 106. Once the vacuum has been released, the lid 104 springs back from being disposed into the storage cavity and the container 100 returns to its un-evacuated shape shown in FIGS. 2 and 3. Other techniques may be used to release the vacuum which may be integrated into the valve design, such as, a button on the top of the valve. In various embodiments, the storage container 100 can include a vacuum indicating feature such as a visible indicator 136. Referring to FIGS. 1, 2, and 3, the indicator 136 is disposed on the top of the lid 104 and can be formed as an even thinner-walled depression made into the thin-walled lid panel. Normally, when the storage cavity 106 is not under vacuum conditions, the indication blister 136 projects upwards from the lid 104. However, as illustrated in FIGS. 5 and 6, when evacuating the storage cavity, the surrounding atmospheric pressure exerts a force upon the indicator 136 causing the indicator 136 to indent or "pop" across the plane of the lid 104 into the storage cavity. Hence, the indicator 136 provides a visible indication that the storage container 100 is in an evacuated condition. If the vacuum is released, the indicator can pop back to it normal upwards projecting condition.
To secure the lid 104 to the base 102, the container 100 can include one or more interlocking latches 140. Referring to FIG. 1, the latches 140 each include a latch plate 142 that is pivotally connected to and extends from the peripheral edge 114 of the lid 104. Each latch plate 142 includes an elongated slot 144 disposed therein. The base 102 includes corresponding latch tongues 146 that project outward from the upper edge of the side panels 110 proximate the opening 112. When the lid 104 is connected to the base 102, the latch plates 142 can be pivoted downward so that the latch tongue 146 is received in the slot 144. In an embodiment, the latch tongue 146 can be sized slightly larger than the slot 144 or offset with respect to the slot so that the tongue is frictionally received in the slot. In other embodiments, the lid may be connected to the base by using a snap fit as shown in FIG. 17 or by using threads on the base and lid. In another embodiment, the lid may be positioned onto the base and held in position when the vacuum is applied to the container.
The base 102 and lid 104 can be made from thin-walled plastic material. The plastic material may be a thermoplastic material, such as, for example, polypropylene, polyethylene, polyethylene terephthalater, nylon, polystyrene, EVA, thermoplastic polyester, metallocene, or combinations thereof. The material may include fillers, colorants, additives, and reinforcements. Referring to FIG. 3, the thickness of a substantial portion or majority of the bottom panel 108 and upright side panels 110 as indicated by dimension 148 can be about 2.5 millimeters or less. Likewise, the substantial portion of the lid 102 can have a thickness indicated by dimension 150 of about 2.5 millimeters or less. In further embodiments, the thicknesses indicated by dimensions 148 and 150 can be in a first range of 0.5 mm to 2.5 mm, in a second range of 1.0 mm to 2.0 mm, and in a third range of 1.5 mm to 2.0 mm.
The thin-walled base and lid can be made by any suitable thin-walled manufacturing method including, for example, thin-walled injection molding, thermoforming, blow molding, vacuum molding, centrifugal molding, compression molding and combinations thereof. Another characteristic of thin-walled parts made typically by injection molding is that they can have large flow-length-to-wall-thickness ratios. Where the thin-walled parts are made by injection molding, hot or molten plastic is inserted under pressure into a mold through a gate or injection site and flows throughout the mold filling voids and thereafter cooling and forming the finished part. The distance that plastic travels from the injection site to an extremity of the mold is known as flow-length. The average thickness of the part along the flow-length distance can be compared to the flow-length distance itself to provide the flow-length-to-wall-thickness ratio. Where the molded part has very thin walls, the ratio can become large, for example, on the order of 90:1 or greater.
As an example of flow-length-to-wall-thickness ratio, referring to FIG. 3, the injection site or gate of the mold for the base 102 can correspond to the center of the bottom panel 108 at the location designated by reference number 152. As can be appreciated, when the base 102 is made, molten plastic must move from the injection site 152 to the upper rim of the side panels 110. This distance from the injection site 152 to the rim of the side panels 110 is then compared to the average wall thickness along the distance to arrive at the flow-length-to-wall-thickness ratio. For the base 102 and lid 104 made from thin-walled techniques, the flow-length-to-wall-thickness can be 90:1 or greater. The flow-length-to-wall-thickness ratio may be in a first range of 90:1 to 300:1, in a second range of 90:1 to 200:1, or in a third range of 90:1 to 130:1.
Another characteristic of making the containers with thin-walls is the internal vacuum pressure that can be maintained in the storage cavity. For example, the stiffness and strength of the bottom panel 108 and side panels 110 is sufficient to resist collapse up to vacuum pressures of about 5 pounds per square inch absolute ("PSIA"). It is believed that at pressures of about 5 PSIA, food items can be sufficiently preserved while the container 100 can generally maintain its shape at least to the extent illustrated in FIGS. 5 and 6. However, at pressures lower than 5 PSIA, the stiffness and strength of the container panels may be overcome and the container will fail. The container has failed if air leaks into the container and/or deformation of the container is such that the container is no longer usable. The container may fail in a first range of 5 PSIA to 13.7 PSIA, in a second range of 6.7 PSIA to 13.7 PSIA, or in a third range of 6.7 PSIA to 12.0 PSIA.
Referring to FIG. 7, there is illustrated an embodiment of a vacuum storage container 200 according to the invention having a feature on the lid 204 designed for protecting the valve element 222. Like the previous embodiment, the lid 204 of the present embodiment is detachably connectable to a generally rectangular base 202 to enclose a storage cavity. To evacuate the storage cavity, the valve element 222 is attached to a center location of the lid 204 and communicates with the storage cavity. Included as part of and protruding upwards from the lid 204 and arranged radially about the valve element 222 is a plurality of embossments 250 which rise higher above the plane of lid than the valve element. In the illustrated embodiment, four embossments 250 are arranged at right angles with each other but, in other embodiments, any suitable number and arrangements can be used. As illustrated, the embossments can each be shaped as three-dimensional parabolas.
Referring to FIG. 8, because the embossments 250 rise above the valve element, they can protect the valve element 222 from coming into contact with other objects that could damage the valve element or otherwise unintentionally release the vacuum inside the storage container 200. One advantage of this function of the embossments 222 is that they allow for multiple storage containers 200 to be stacked one upon another which facilitates transportation and storage of the containers. Also illustrated in FIG. 8, the embossments 250 can be formed as hollow structures depressed into the lid 204 and with the same thin-walled thickness of the rest of the lid. However, in other embodiments, the embossments can be solid and can include other shapes and sizes. The embossments may also provide additional strength to the lid.
For example, referring to FIG. 9, in another embodiment of the vacuum storage container 300, thin narrow fingers 350 rather than wide parabolic embossments protrude from the lid 304. In the illustrated embodiment, the fingers 350 are again arranged radially about the valve element 322 and at right angles with each other, but in other embodiments can have any other suitable arrangement or number. To protect the valve element 322, the fingers 350 extend higher above the plane of the lid than the valve element.
Referring to FIGS. 10 and 11, there is illustrated another embodiment of a storage container 400 having a lid 404 with a different type of valve element 422 attached thereto. To protect the valve element 422 in the illustrated embodiment, the lid 404 includes a centrally located depressed region 424 that deflects partly into the storage cavity 406. In the illustrated embodiment, the depressed region 424 can have a rectangular shape suitably sized to accommodate the nozzle 432 of a vacuum device 430. In other embodiments, the depressed region 424 can have any other suitable shape. The valve element 422 is located within this depressed region 424 and is generally recessed below the plane of the lid 404. Accordingly, multiple storage containers 400 can be stacked one on top of another without interfering or damaging the valve element 422. In other embodiments, the container may use the embossments noted herein to protect the valve.
The particular valve element 422 illustrated in FIGS. 10 and 11 is a duckbill valve element. The duckbill valve element 422 can be made of any suitable resilient or flexible material and includes a tubular base portion 426 from which projects two upward projecting lips 428 that normally oppose and press against each other along a seam line 429. The tubular base portion 426 is attached over a hole 405 disposed through the lid 404 within the depressed region 424 for example, by adhesive or by press-fitting the tubular base portion into the hole. When a vacuum device 430 is interfaced with the duckbill valve clement 422, the lips 428 can separate thereby opening the seam line 429 and thus allowing air to be removed from the storage cavity 406. When the vacuum device is turned off or removed, the lips 428 resiliently return to sealing against each other along the seam line 429 thereby preventing the environmental air from be drawn into the storage cavity. Other embodiments of the duckbill valve may be used.
Referring to FIGS. 12, 13 and 14, there is illustrated another embodiment of a vacuum storage container 500 having another type of valve element, in particular, a diaphragm valve element 522. The diaphragm valve element 522 may be positioned in a depressed region 524 disposed into the lid 504 such that the valve element is generally recessed below the plane of the lid in order to protect the valve element. In its normally closed position, illustrated in FIG. 12 and 14, the diaphragm valve 522 includes a generally planar flexible diaphragm 526 with a circular peripheral edge 528 and a central aperture 530 disposed therein. Excess material 532 in the form of a folded collar or sleeve is included within the plane of the flexible diaphragm 526 and extends annularly and concentricly about the aperture 530. To enable communication between the diaphragm valve element 522 and the storage cavity 506, one or more holes 505 are disposed at off-center positions through the depressed region 524 of the lid 504. The diaphragm valve 522 is then attached by its peripheral edge 528 to the lid 504 such that the excess material 532 can generally align over the lid holes 505. The inner portion of the flexible diaphragm 526 including the central aperture 530 adjacently overlay a solid portion of the depressed region 524. Hence, fluid communication between the lid holes 505 and the diaphragm aperture 530 is not normally possible.
Referring to FIG. 13, when the nozzle of a vacuum device 550 is interfaced with the diaphragm valve element 522 and suction applied, the rolling collar or sleeve 532 unfurls and allows the central portion of the flexible diaphragm 526 to lift away from the lid 504. Hence, air from the storage cavity 506 can move through the lid holes 544 and exit through the diaphragm aperture 530. Once the nozzle of the vacuum device 550 is removed or the vacuum device is turned off, the rolling collar or sleeve 532 refurls so that the central portion of the diaphragm 526 again overlies the depressed lid region 524 scaling the storage cavity 506 as illustrated in FIG. 12. Other embodiments of a diaphragm valve may be used. Referring to FIG. 16, there is illustrated another embodiment of a vacuum storage container 600 wherein the base 602 and lid 604 are integrally joined to each other by a hinge 605. For example, the hinge 605 can be a flexible living hinge which extends between and is integrally formed with both an upright side panel 610 of the base 602 and the peripheral edge of the lid 604. The living hinge 605 can extend along one of the sides of the storage container 600. To access the storage cavity 606, the lid 604 may pivot about the living hinge 605 away from the base 602. In a further variation, to secure the base 602 and lid 604 together when connected, a latching mechanism 640 of the aforementioned type can be included on the container side opposite the living hinge 605. In other embodiments, the base and lid may be secured using other techniques noted herein, such as, a snap fit.
Referring to FIG. 17, there is illustrated in detail another embodiment of a vacuum storage container 700 wherein, instead of the aforementioned latching mechanism, the base 702 and lid 704 can be secured together by a snap-fit relationship. Specifically, the lid 704 includes a three-sided groove 718 formed about its peripheral edge that can receive a vertically projecting tongue 716 extending from the upper edges of the base 702. For providing an airtight seal, a resilient gasket 720 can be included in the groove 718. To facilitate the snap-fit relationship, a protrusion 722 can extend inwards from an outer wall of the groove 718 and a corresponding protrusion 724 can extend outwards from the vertical tongue 716. When the tongue 716 is received in the groove 718, the protrusions 722, 724 can slide past and then interlock or "snap" behind one another. The protrusions 722, 724 can be placed continuously or intermittently about the peripheries of the base 702 and lid 704.
All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.
The use of the terms "a" and "an" and "the" and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms "comprising," "having," "including," and "containing" are to be construed as open-ended terms (i.e., meaning "including, but not limited to,") unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., "such as") provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.
Preferred embodiments of this invention are described herein, including the best mode known to the inventor(s) for carrying out the invention. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventor(s) expect skilled artisans to employ such variations as appropriate, and the inventor(s) intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.

Claims

A rigid storage container (100; 200; 300; 400; 500; 600; 700) comprising:
a base (102; 202; 602; 702) having a base wall thickness (150), the base (102; 202; 602; 702) providing a storage cavity (106; 406; 506; 606) accessible by an opening (112);

a lid (104; 204; 304; 504; 604; 704) having a lid wall thickness, the lid (104; 204; 304; 504; 604; 704) is positioned over the base (102; 202; 602; 702) for covering the opening (112);

one of the base wall thickness (150) and lid wall thickness is about 2.5 millimeters or less; and

a valve element (122; 222; 322; 422; 522) communicating with the storage cavity (106; 406; 506; 606), wherein the lid (104; 204; 304; 504; 604; 704) includes an upward projecting embossment (250) near the valve element arranged to rise higher above a plane of the lid than the valve element (252) and wherein the lid (104; 204; 304; 504; 604; 704) includes a recessed portion (424; 524) depressed toward the storage cavity (106; 406; 506; 606), the valve element (122; 222; 322; 422; 522) being attached to the lid (104; 204; 304; 504; 604; 704) within the recessed portion (424; 524).
The storage container of claim 1, wherein the wall thickness (150) is in a range of 0.5 millimeters to 2.5 millimeters.
The storage container of claim 1 further comprising a gasket between the base (102; 202; 602; 702) and the lid, wherein preferably the gasket (120; 720) is compressibly deformed when the lid engages the base.
The storage container of claim 1, wherein the base (102; 202; 602; 702) includes a tongue (116; 716) projecting from a rim outlining the opening (112), and the lid (104; 204; 304; 504; 604; 704) includes a corresponding groove (118; 718) for receiving the tongue (116; 716) when the base (102; 202; 602; 702) and lid (104; 204; 304; 504; 604; 704) are connected.
The storage container of claim 4, further comprising a resilient gasket (120) in the groove (118; 718).
The storage container of claim 1, further comprising a latch (140) for securing the lid (104; 204; 304; 504; 604; 704) and the container (100; 200; 300; 400; 500; 600; 700).