STRAINERS AND PLUGS

FIELD OF THE INVENTION

The present invention refers to a disposable strainer designed for use in sinks, bathtubs, drains and so on.

BACKGROUND OF THE INVENTION

It is nowadays customary to cover the drains of sinks with strainers that are usually made of metal or plastic and are designed to prevent masses of waste from entering the plumbing system. It is customary to manually collect the waste on the strainer, remove the strainer from the drain hole, empty the waste into the garbage can and return the strainer over the sink's drain hole for further use.

The need to collect the waste from the bottom of the sink by hands, pile it up on the strainer, remove the strainer, empty the waste into the garbage can, and clean the strainer from pieces of scummy waste that often stick to it, is unpleasant, to say the least, and constitutes a problem for the general public. The present invention offers an appropriate, efficient and inexpensive solution to this problem.

US 7,442,296 to Won describes a disposable drain strainer that is removably received within a drain opening having an adjacent drain rim substrate. The strainer has a strainer portion, a ring portion, and a seal release mechanism. Top and bottom surfaces of the ring portion are adapted to sealingly engage the drain rim substrate. The seal release mechanism is integral with the ring portion, and facilitates release of the seal so that the strainer can be readily be removed from the sink and discarded. The strainer is described to preferably have a thickness no greater than 0.091 cm (910 μιη). However, it will occur to the skilled in the art that for various reasons, such be made very much lower than that thickness, for example injection molding cannot make strainers thinner than 400μιη.

One object is to improve the adhesion of strainers to sinks; another to improve the printablilty of strainers; yet another is to provide strainers that are more efficient; another is to provide strainers easier to produce. Yet another is to reduce the waste of material by making the strainer thinner - than attainable under the limits of production by mold injection.

SUMMARY OF THE INVENTION

According to one aspect, an extra-thin and flexible strainer or plug, having a thickness of between 150 and 350 μιη is provided.

According to another aspect, a sink bath comprising: a surface; a drain, and a strainer or plug, the strainer or plug configured to fit over the sink's/ bath's drain and adhere to the sink/ bath surface adjacent to the drain, the strainer characterized as having a rim extending to at least 10 mm onto the sink/bath surface is provided.

According to yet another aspect, a strainer or plug comprising a circumferential ring, a middle concave part and a circumferential side is provided, the ring characterized as being at least 15 mm wide.

The strainer or plug may be configured for single use or for a small number of uses.

The strainer or plug is preferably made of a material that self-adheres to a wet sink surface.

Preferred embodiments further comprise at least one lifting tab.

Some embodiments further comprise materials that can be printed upon.

Some strainer embodiments further comprise tiny protrusions in the perforated bottom of the strainer's middle part.

Some embodiments are configured to exude a fragrance. Some strainer embodiments are composed of one or two strainers that are positioned one over the other and are joined in a way that enables them to be rotated in relation to one another.

Some strainer embodiments have two tabs are opposite each other.

Some strainer embodiments with tabs have the tabs are marked to allow easily identifying the tabs.

In some preferred embodiments the tabs are configured to allow breaking the adherence of the strainer or plug to the sink/bath surface.

Some strainer embodiments comprise recyclable or recycled materials.

Some strainer embodiments comprise materials selected from a group comprising PLA, PET, PP and PS, with the proviso that the materials exclude materials that lose mechanical strength within hours of contact with liquid.

Some strainer embodiments further comprise a material that catalyzes or facilitates decomposition or degradation of the strainer or plug.

Preferably, embodiments are produced by vacuum forming / thermo- forming.

Preferably, the extra thin strainer embodiments comprise a circumferential ring at least 10 mm wide.

Some embodiments are made of material that is sufficiently flexible to allow picking the strainer or plug as a sack.

Preferably, the strainer rim is sufficiently wide to prevent refuse from falling in a sink's drain when the strainer is removed from the sink.

Preferably, the rim is sufficiently wide to collect refuse not reaching a sink's/bath drain when the strainer is placed over the drain.

In some embodiments all surfaces of the plug or strainer are printed.

According to another aspect, vacuum forming /Thermoforming a strainer or plug is provided.

According to another aspect, a sink/bath is provided, the sink/bath comprising: a surface; a drain, a metal cover and a strainer or plug, the strainer or plug configured to fit over the sink's/bath's drain and adhere to the sink surface adjacent to the drain, the strainer characterized as having a rim extending to at least 15 mm beyond the metal cover.

Some embodiments further comprise OXO.

Some strainer embodiments have a ring at least 20mm wide.

BRIEF DESCRIPTION OF THE FIGURES

The drawings attached to the application are not intended to limit the scope of the invention and the possible ways of its application. The drawings are intended only to illustrate the invention and constitute only one of many possible ways of its application.

Figure 1 depicts a perspective view of a strainer that is composed of a circumferential ring with a lifting tab, and a concave middle part that is composed of a circumferential vertical side and a bottom with perforations; Figure 2 shows the strainer of Figure 1 in a view from above;

Figure 3 illustrates the strainer of Figure 1 in a side view, showing the lifting tab on the left;

Figure 4 shows the same strainer, viewing the lifting tab as facing into the page;

Figure 5 depicts in perspective view a strainer with additional protrusions designed to help trap waste and prevent it from going down the drain;

Figure 6 shows the strainer of Fig 5 in a cross-section side view;

Figure 7 depicts a side view of a double strainer made up of one perforated strainer and a conforming plug;

Figure 8 illustrates separation of the perforated strainer and plug of the double strainer;

Figure 9 schematically shows a side view of a double strainer made of two perforated strainers; Figure 10 shows a side view of the strainer depicted in Fig. 9, in which liquid passes via the strainer;

Figure 11 shows a top view of the bottoms of the two perforated strainers depicted in Fig. 9, in which liquid may pass via the strainer;

Figure 12 shows a top view of the bottoms of the two perforated strainers depicted in Fig. 9, in which liquid may not pass via the strainer;

Figure 13a shows a roll of plastic film for forming strainers;

Figure 13b shows the heating of a plastic film in a vacuum forming/

Thermoforming system;

Figure 13c shows the plastic film start to deform in the vacuum forming/

Thermoforming system;

Figure 13d shows the plastic film brought into contact with a vacuum mold in the vacuum forming/thermoforming system;

Figure 13e shows the vacuum formed sheet in the shape of a strainer on the mold;

Figure 13f shows the strainer separated from the mold.

DETAILED DESCRIPTION OF THE INVENTION

Strainers and plugs are provided. For simplicity, strainer embodiments are described hereinbelow, except for some specific examples of plugs. The description below of strainers thus is to be applied mutatis mudandis to plugs, unless a particular description of plugs is explicitly described following regarding those strainer embodiments.

The strainers are designed to be used over the drain holes of sinks, bathtubs, and so on. The strainer embodiments 1 in Figures 1 to 4 are intended to be used once or a small number of times at the most and have the general composition of a circumferential ring 2 and a middle part 3 with perforations 6.

The circumferential ring 2 constitutes the external rim of the strainer 2 and has the general shape of a flat, closed ring. The middle part 3 can be flat (particularly for use over drain holes in showers that have a metal lattice in the floor), concave or convex, and it can have a circumferential vertical side 4 and a bottom 5 with perforations 6 so as to form a general structure of a cylindrical or dome-like bowl. The circumferential side 4 can be vertical if the middle part has the general shape of a cylinder or it may be curved if the middle part has the general shape of a dome. The middle part 3 can be either convex or concave. The strainer 1 is made of one integral piece.

According to one aspect, the external diameter of the circumferential ring 2 is such as to essentially prevent waste falling into the drain when the strainer is picked up, as well as allow prolonged adhesion of the strainer to the sink surface when the trainer is placed on the sink drainage hole. . The external diameter of the strainer/plug is generally variable, for example about 135 mm in sinks with drain holes of 85mm that have a metal cover of 105mm, although it may be larger or smaller, provided the adhesive property of the strainer 1 is retained: all other parameters being equal, the larger the circumferential ring 2, the stronger the adhesion of the strainer 1, as will be explained later on in the application. In terms of ring width, the ring is typically at least 15mm wide so as to extend and contact at least 10 mm onto the sink or bathtub's surface: in many sinks there is a depression of a few mm surrounding the sink's drain, and the ring has to span and extend beyond this depression well onto the surface, and thus strainers, more particularly for sinks, preferably have a somewhat wider width of at least 20mm, whereas plugs for baths without such depressions may have a smaller diameter. The diameter of the middle part 3 corresponds, in general, to the dimensions of the drain holes the strainer 1 is intended to be used over. The depth of the middle part 3 (if it is concave) or its height (if it is convex) can range from 40 mm deep to 10 mm high, although other dimensions are also possible.

According to another aspect, the strainer 1 is very thin, preferably less than 400 microns thick and down to about 150μιη or less, dependent upon the strength of the material from which the strainer is made. The material has to be sufficiently thick to allow detaching the strainer from the sink surface and picking up the strainer loaded with refuse, without tearing or collapsing. In some embodiments, this novel minimal thickness enables the strainer 1 to be highly flexible. The unique structure of the strainer 1 enables both very efficient, fast and very inexpensive manufacture, being manufactured from a much reduced amount of material compared to strainers made by injection molding, conserving storage and shipping space. The environmental impact of the product is thus much reduced both in manufacture and in disposal. In addition, the fact that the strainer 1 is extra-thin and/or has a wide rim may enhance its adhesion, as will be explained later on.

In some embodiments, the strainer 1 can self-adhere upon contact with water. This property of the strainer 1 stems, among other things, from the type of materials used to manufacture it, its overall design, e.g. flexibility (from material and thickness) and surface area of the rim, and the unique property of water molecules that results in the creation of attraction and adhesion forces. The strainer 1 is made of a polymeric material, preferably of a type that is not mechanically compromised by short period wetting such as recycled and recyclable HDPE, PLA, PS, PP or PET with or without additives, including OXO, which is used to catalyze the biodegradation of the material. Paper is generally unsuitable, as it will lose its mechanical strength within minutes of becoming wet. All of the above materials can be supplied in extra thin sheets and extremely flexible and can be folded rapidly and efficiently. Most importantly, all of the above materials can self-adhere, such that when the strainer 1 [or more accurately, the circumferential ring 2] is placed on a sink surface and/or bathtub surface and/or basin surface with a drain hole and/or on the circumferential ring of the drain hole itself (hereinafter referred to as the "basin surface"), the strainer adheres efficiently to the basin surface thanks to the moisture captured between the underside of the circumferential ring 2 and the surface of the basin surface. The adhesion occurs, among other things, thanks to the vacuum created between the underside of the circumferential ring 2 and the surface of the basin, and also due to the fact that water penetrates between the two surfaces, causes attraction and adhesion forces between them.

In preferred embodiments wherein the rim is meant to adhere to the sink, the circumferential ring 2 is relatively large and its external diameter should preferably be significantly greater than that of the drain hole, i.e. at least 10mm wider, so that its contact area with the basin surface is large enough to create effective adhesion. In such a way, the strainer 1 is positioned firmly over the drain hole and does not shift. This adhesion is caused not only due to the weight and geometry of the strainer (in that the concave part fits into the drain hole) but also due to the properties and structure of the strainer and the properties of the water. The wide rim of the strainer 1 also enables the user to accumulate a greater quantity of waste and dirt on it, and the fact that the strainer 1 is extra thin and flexible also enhances the effectiveness of its adhesion. The wide rim also helps prevent from refuse falling into the drain when the strainer is lifted off the sink surface. It should be appreciated that commercially available strainers that are not as wide are precarious, as they expose the sink to blockages due to inadvertent spillage of waste into the drain during their manipulation.

The strainer 1 can be round, elliptic, or have any other geometric shape. As mentioned, the middle part 3 of the strainer 1 has perforations 6 and is designed to be positioned over the drain hole. The strainer 1 enables water to flow through the perforations 6 into the drain, whereas the waste is stopped and accumulates on the strainer 1. The strainer 1 can be equipped with one or more lifting tab 8 to facilitate its removal in order to discard it into a garbage can along with the waste accumulated on it as well as to help lift the strainer off the sink surface. In preferred embodiments, there are at least two tabs, preferably opposite each other. Two tabs may allow to stably lift the strainer in the shape of a sack, thus minimizing spillage and visibility of refuse on the strainer. The tabs themselves may be made of printable material, and be printed upon or highlighted, either in part or over their entire surface, to help a user locate the tabs.

In some embodiments, the material the strainer 1 is made of can be of a type that can be printed on, in which case the strainer 1 may serve as advertising space, (for instance for detergents, or kitchen products) or have some aesthetic print on it. In some embodiments, the material of the strainer 1 is made orcan contain or have a coating containing a fragrance.

In some embodiments a strainers such as Γ, shown in Figures 5 and 6 have tiny protrusions 7 on the bottom 5 of the middle part 3' so that the waste is caught on the protrusions and accumulates on them, creating an empty pocket between the waste and the strainer base, and preventing the perforations 6 from being clogged. In this way, water can flow freely through the perforations 6 into the drain hole even when waste has accumulated on the strainer Γ and thus improves drainage. The protrusions also improve the trapping and capture of the waste and prevent it from getting washed down the drain.

Other embodiments refer to double strainers 10, 10' shown in Figures 7 to 12 that are made up of two strainers of the kind described above or a strainer above a plug. In Figures 7 to 8 a strainer 12 is placed over a plug 14. In Figures 9 to 12 a strainer 12 is placed over another strainer 12'. For simplicity, only the bottom part of the strainer 12' is shown. The two strainers 12, 12' are placed one on top of the other and their centers are joined together in such a way that they can be rotated in relation to one another. When the perforations 6 on the two strainers 12, 12' are aligned, Figures 10 and 11, water can flow freely from the basin into the drain hole. Alternatively, one of the two strainers 1 can be rotated slightly so that the perforations 6 on the two strainers are not aligned and an impervious surface is formed, as in Figures 9 and 12. In this position, the double strainer 10 serves as a kind of stopper or plug, preventing water from flowing down the drain. The double strainer 10 can thus serve both as a strainer and as a stopper for the relevant basin according to need. In addition, the double strainer 10' is less likely to drip when it is removed and discarded along with the waste accumulated on it. The double strainer 10 can be composed of two separate parts - one strainer 1 with perforations 6 and a second "strainer" 1 without perforations that serves as a stopper.

The double strainer minimizes dripping of liquids from the strainer during the extraction of the strainer from the sink and transfer of the detritus to the rubbish bin.

Further embodiments refer to a component (not shown) that resembles the aforementioned strainer but has no perforations and is used as a single-use stopper for the drain hole and/or as a kind of drip-tray when discarding the waste from the drain hole into the garbage can. Optionally, the lifting tab in these embodiments span the centre of the strainer, to allow a larger surface area to be available for contact between the rim and the sink surface and thus maintain a complete seal and prevent seepage of water to the drain.

The strainer 1, may be used as follows: The user places the disposable strainer over the drain hole. The presence of residual water causes the strainer to self-adhere to the sink and prevents it from moving from its position over the drain hole. The user can collect the waste on the strainer, and if necessary, fold it so that it envelopes the waste and discard it into the garbage can along with the waste that is in it. In this sense, the strainer is disposable. When the strainer is used over a bathtub drain it can save the user the unpleasant task of collecting and removing hair that is caught in the drain's permanent lattice or in the drain hole itself. The strainer may also be used over floor drain holes (usually located in the bathroom floor) when the floor is being washed and the wash water is drained through the said drain hole. Thus the strainer prevents waste from entering into the drain system along with the water and also saves

1 the user the unpleasant task of having to collect such waste from the wash water.

Figure 13a shows an extra thin sheet of printable polymeric material, typically thinner than about 350μιη.

In general, plastic utensils are manufactured by injection molding or

Vacuum forming/ Thermoforming (herein below abbreviated as VF). Utensils of a size and shape complexity comparable to those of strainers/plugs, manufactured by injection molding, are limited to a minimal thickness of about 400μιη. Wide rims and sunken centers render the strainers impossible to produce to that thinness by injection molding.

There are a number of advantages to manufacture of multi-planar extra thin perforated strainers and plugs by VF. The thinness much improves the adhering strength of the strainers, allowing them to stay in place even inder a very strong stream of water. The increase adherence is due in part to the increased flexibility of the strainer that allows the strainer to better conform to every minute feature of the sink's surface. The increased adherence as well as the extra thinness also allows washing the detritus in a relatively strong stream of water onto the strainer, whereas thicker strainers have more limited adhesion and form a physical barrier due to their height above the sink surface.

Another advantage consequent to manufacture by VF is the ability now open to print over the entire surface of the strainer by simpler, cheaper and faster technologies, including the concave part, walls, contours, tabs etc on a sheet's surface, possibly with unique designs, advertisements and/or uniquely designed strainers), whereas injection molding only allows printing on the rim or the bottom of the strainer (to be precise - only on flat surfaces) or very slow and complex printing by technologies suitable for printing on 3D objects. The larger printable surface allows printing content that would be impossible to create in injection- molded strainers.

1 Moreover, the higher the proportion of recycled material in the material to be molded, the harder it is to produce quality printing on any surface of the molded material. However, surprisingly this limitation does not apply to VF formed strainers.

Referring to Figure 13b, an extra thin plastic sheet 2110 is typically decorated or printed upon (not shown), before being placed in a VF system 2300. The VF system comprises a vacuum block (mold) 2330 having suction holes 2340, heating element 2350, sheet holders 2360 and vacuum machine 2370.

Sometime after heating, the sheet 2110 becomes pliable, Figure 13c.

The sheet 2110 is then lowered to the vacuum block 2330, Figure 13d. A vacuum is then applied via the suction holes 2340, upon which the sheet 2110 conforms to the shape of the vacuum block 2330, Figure 13e. After cooling, the formed sheet 2110 is raised from the block 2330, Figure 13f, and removed from the VF system. The formed sheet may now be perforated to form a strainer, or may remain un-perforated to be a plug.

Some hydrophobic materials, for example polymers such as polypropylene and polystyrene, might adversely affect the adhering strength of the strainers to the sink surface since they repel water and thus do not strongly adhere to the water as hydrophilic materials do. Some materials might have a low specific-gravity, lower than water's, that may interfere with adherence. Nevertheless, the strainers and plug shave been found to have excellent adherence even with these materials, thanks to either/or the wide rims, the thinness and the flexibility of the material. . A flip side of the hydrophobicity is that the upper surface of the strainer repels water, which facilitates removal of the strainer without drips and may decrease the adhesion of the wet offal to the surfaces of the strainer.

Notably, most sinks have a metal cover over the drainage hole of the sink. The strainer embodiments have a rim that extends beyond the cover to the

1 ceramic or metal surface of the sink itself. The extension to the surface of the sink is particularly important in ceramic sinks, since it has been found that the strainers made of hydrophobic materials adhere better to wet ceramic surfaces than to wet metal surfaces.

Preferably, the strainer rim extends in such drains to at least 10mm beyond the cover.

The strainer 1, subject of the present invention, constitutes an efficient and inexpensive solution to the aforementioned problems and offers one or more of the many advantages, as follows: (a) Due to the strainer's wide rims in some embodiments, a larger amount of waste may be accumulated on it. (b) Use of the disposable strainer avoids the need, the trouble, and the unpleasantness of emptying the waste into the garbage can and rinsing the strainerbefore reusing it, as in the case of the standard strainer, (c) Using the disposable strainer is convenient, efficient, and more hygienic. The wide rim and its thinness allow efficient flow of refuse into the concave part and to accumulate a large quantity thereon. All these qualities help to minimize and ease any dealing with the rubbish, (d) The lifting tabs at or near the edges of the rim which allow minimal contact with the detritus, facilitate cancellation of adhesion and enable easily picking up the strainer, (e) The wide rim minimize invasion of refuse not stacked on the strainer into the drainage system, during disposal of the rubbish (optionally together with the very thin strainer), (f) The wide rim can be used for unique prominent advertisements, decoration etc. (g) The thinness in some embodiments allows printing on the entire surfaces of the strainer. Typically, only the top surface is printed. Such printing is not present or feasible in commercially available strainers, (h) When the invention is implemented on bathtubs and floor drains holes (usually located in bathroom floors), the strainer 1, subject of the invention, constitutes an efficient way of preventing waste from entering the plumbing system, (i) Most importantly, the strainer 1 self-adheres to surfaces upon contact with water, having a wide rim

1 and/or being very thin and very lightweight, and so adheres well to the surface around the drain hole.

1