Patent Application
20250050363
The invention relates to a foam dispenser. This comprises a plastic bottle made of a flexible plastic having a bottle opening, a closure cap that seals the bottle opening and has a dispensing opening for a foam, a foam-generating device for foaming a solution, said device comprising a chamber having at least one wall, at least one inlet for air in a wall of the chamber, and at least one inlet for liquid in a wall of the chamber, and at least one porous body that is arranged in the chamber, the foam-generating device being arranged in or connected to the closure cap, and a riser pipe that is arranged inside the bottle and is connected to an inlet.
Disinfectants or cleaning agents are often alcoholic solutions, since alcohols have a good microbiocidal effect depending on the chain length. Such products are available as a solution, gel or foam. Alcoholic solutions are difficult to foam, as alcohol is a defoaming agent. To generate a foam in hand-operated dispensers or automatic dispensers, a foam-generating device is used when foaming alcohol-based products, which ensures that a foam is produced when the liquid and air are mixed. The dispenser systems, especially in the case of mechanical dispensers, often consist of a plurality of sensitive components and are thus complex to manufacture and more expensive.
GB 1 478 607 A describes a hand-operated device for producing and dispensing foam using a bottle with a riser pipe. The bottle contains a rigid porous body in which liquid and air are mixed. The air flow is regulated via a valve.
The object of the invention is to provide a hand-operated foam dispenser which overcomes the disadvantages known from the prior art and, in particular, can be produced inexpensively with few components and enables the foaming of alcoholic solutions.
The object is solved according to the invention by a foam dispenser for foamable products according to patent claim 1.
Further embodiments are the subject of the subclaims or are described below.
The foam dispenser according to the invention comprises
The porous body consists of an open-cell foam material and the open-cell foam material in the chamber has a density of more than 0.03 g/cm3. The density is determined by measuring the outer dimensions of the porous body, determining the weight of the porous body and calculating the density from the weight and volume. The measurement or determination of the outer dimensions of the porous body is based on its dimensions in the chamber.
According to the invention, a porous body is understood to be at least one porous body, i.e. when a porous body is described, exactly one porous body or a plurality of porous bodies are included.
The foam dispenser according to the invention is a manual foam dispenser which is hand-operated, i.e. in which the foam is generated by squeezing the bottle by hand. The plastic bottle is thus made of a flexible plastic so that it can be squeezed. The plastic bottle is preferably made of polypropylene (PP), polyethylene terephthalate (PET), low density polyethylen (LDPE), high density polyethylen (HDPE) or a mixture thereof, particularly preferably of HDPE and LDPE.
The foam dispenser according to the invention preferably contains an alcoholic or non-alcoholic mixture, which is typically a solution. The mixture contains at least one surfactant or a surface-active substance that acts as a foamable substance. The surfactant is preferably a silicone surfactant. Preferably, the surfactant or the surface-active substance is present in the mixture in an amount of 0.2 to 5% by weight, particularly preferably 0.2 to 2.5% by weight. The foam dispenser according to the invention can be used for cleaning agents for skin and hands, for surfaces or instruments, or for disinfectants for skin or hands, for surfaces or instruments, for wound cleaning agents or wound disinfectants or for cosmetic agents, such as hair or skin cleaning agents or hair or skin care products.
The plastic bottle preferably contains an alcoholic solution, particularly preferably an alcoholic disinfectant. The alcoholic disinfectant preferably contains
The plastic bottle can also contain a low-alcohol solution, such as a surface disinfectant. The low-alcohol solution preferably contains
Alternatively, the plastic bottle can contain an aqueous solution, such as a soap formulation.
The aqueous solution preferably contains
To foam an alcoholic composition, it must be mixed with foamable substances, i.e. surfactants or surface-active substances. Alcohols disrupt the surface tension and are also used as defoamers. The foaming of an alcohol-containing composition thus requires corresponding chemical excipients and additionally further physical/mechanical means, such as a foam dispenser which, according to the invention, has a chamber having at least one porous body in which liquid and air can be mixed to generate foam.
The open-cell foam material is preferably made of a polymer material, particularly preferably polyurethane (PUR) or acrylonitrile butadiene gum, also known as nitrile butadiene rubber (NBR).
The open-cell foam material in the chamber has a density of more than 0.03 g/cm3. The density refers to the density of the porous body placed in the chamber, which body can be uncompressed or compressed. For an uncompressed porous body, the density of the uncompressed foam in the chamber is specified. For a compressed porous body, the density of the compressed foam in the chamber is specified. Preferably, the foam material placed in the chamber has a density of at least 0.035 g/cm3, particularly preferably at least 0.045 g/cm3. Further preferably, the foam material placed in the chamber has a density of at most 0.08 g/cm3, preferably of at most 0.06 g/cm3. The foam material in the chamber preferably has a density of more than 0.03 g/cm3 and no more than 0.06 g/cm3.
In the uncompressed state, the foam material preferably has a number of pores (=number of pores along a straight line per linear inch) of 50 to 130 pores/inch, preferably 60 to 100 pores/inch, particularly preferably 60 to 80 pores/inch, for example around 70 pores/inch. The cell count is preferably determined microscopically.
The foam material preferably has a mean pore size of 0.3 mm to 0.9 mm in the uncompressed state, measured according to ASTM D 3576-2004, preferably from 0.4 mm to 0.8 mm.
In a preferred embodiment, the porous body is compressed in the chamber, wherein the porous body is preferably compressed by 10% to 50% of the volume of the uncompressed body, particularly preferably by 15% to 50%, more preferably by 35% to 50% and most preferably by 35% to 40%. Compression increases the density of the foam and can also change the shape of the foam's pores. Both the increase in density and the change in shape can have the effect that the solution can be foamed better.
For example, the chamber can have a volume of 1 cm3 to 5 cm3, preferably 1 cm3 to 3 cm3 and particularly preferably 1 cm3 to 2 cm3. In particular, the chamber has a volume of 1.4 cm3 to 2 cm3. The porous body or the total number of porous bodies preferably fills the volume of the chamber to at least 80%, more preferably to at least 85%, even more preferably to at least 90%, particularly preferably to at least 95% and in particular essentially completely.
The porous body is preferably fixed to the wall of the chamber, preferably by being clamped in its position in the chamber by contact with the wall. This ensures that the liquid has to flow through the pores of the foam and prevents the porous body from floating on the liquid. The porous body is particularly preferably in full contact with the side walls of the chamber, so that the liquid must flow through the foam material when flowing through the chamber and no liquid can flow past the porous body. In this case, the porous body has the same cross-section as the chamber. The porous body preferably has a height that is at least half the length of the chamber, since a particularly good foam is produced if the liquid and air have a sufficient distance to travel in which they can mix in the pores of the foam material.
In one embodiment, the chamber is at least partially cylindrical and the porous body is cylindrical. If the chamber contains a plurality of porous bodies, these can, for example, be shaped as partial pieces of a cylinder, e.g. as two half cylinders or as pie pieces, which in total again have the shape of a cylinder.
When using a plurality of porous bodies, all porous bodies are preferably made of the same foam material. This has the advantage that the foam dispenser is easier and cheaper to manufacture, as there is no need to keep different materials in stock. In addition, the same mixing effect is achieved in all areas and a uniform foam is produced if the porous bodies are made of the same material.
The chamber, which is preferably at least partially cylindrical, preferably has a chamber base and at least one chamber wall, which extends from the chamber base in the direction of the top side of the closure cap, wherein at least one inlet is arranged in the chamber base and at least one inlet is arranged in a chamber wall. If the chamber base is circular, the chamber has a curved chamber wall.
In one embodiment, the chamber has only a single inlet in the chamber base, which inlet is connected to the riser pipe and preferably forms the inlet for air when used upside down. An air chamber can be arranged in a connecting piece between the end of the riser pipe and the inlet, from which air chamber the air flows through the inlet into the chamber.
The chamber preferably has at least two, preferably three to six, particularly preferably three or four inlets in the chamber wall or the side wall of the chamber, wherein the inlets are preferably arranged evenly spaced apart and preferably form the inlet for liquid when used upside down.
The air inlet is the inlet that is connected to an air reservoir in the bottle during use. The liquid inlet is the inlet that is connected to a liquid reservoir during use. The riser pipe, which is arranged inside the bottle, is preferably connected to an inlet in the base of the chamber and preferably forms the inlet for air.
In a preferred embodiment, the chamber is at least partially designed as a double-walled hollow cylinder. The double-walled hollow cylinder has an inner and an outer cylinder, which are arranged concentrically to each other in the overlapping area and are preferably offset relative to their longitudinal axis or have different lengths, so that the area at the chamber base is only single-walled. The porous body is arranged in the inner cylinder. In this embodiment, the inlets in the side wall of the chamber are preferably arranged only in the outer cylinder, particularly preferably only in the lower, non-double-walled part of the chamber. The inner hollow cylinder can be connected to the closure cap and, for example, be formed in one piece with the closure cap.
The embodiment of the chamber as a double-walled hollow cylinder is particularly advantageous because the liquid flow is directed through the double-walled cylinder. The liquid first enters the outer of the two hollow cylinders and thus the foam-free area and is then transported to the lower opening of the inner hollow cylinder. This allows it to flow into the porous body from below so that the entire length of the porous body can be utilized for foam generation. Since the foam material is fixed in the inner cylinder, the foam dispenser is easier to assemble, since the porous body is already in position when the closure cap is screwed or clamped and does not have to be fixed during the screwing or clamping process. It is also easy to replace the porous body by replacing only the inner cylinder of the chamber or the closure cap connected to the inner cylinder.
The foam dispenser according to the invention can be used to generate foam either upside down, i.e. with the bottle turned upside down with the bottle base pointing upwards, or upright, with the bottle base pointing downwards. Upwards means vertically upwards towards the ceiling and downwards means vertically downwards towards the floor. The bottle can also be held at a slight angle during use, this is also included in upside down and upright.
When generating foam, if the bottle is closed, the outlet opening of the bottle is opened first, e.g. by opening a hinged lid, pulling off a protective cap or pulling up a pull closure. The bottle is
This generates foam, which exits through the outlet opening in the closure cap and is collected with the other hand. To foam the liquid, the porous body made of open-cell foam material is located inside the chamber, which foam material has cavities in which air and liquid are mixed together to generate a foam. Optionally, a part of the chamber in which at least one inlet is located is empty and does not contain a porous body. Air and liquid are preferably already partially mixed after entering the chamber before they are transported premixed into the porous body.
If the bottle is used upside down, foam is generated as follows:
The chamber having the porous body has one or more inlets, which lie below the liquid level inside the bottle in the upside down position. The riser pipe is located at the top of the chamber when the bottle is inverted and ends in the air space of the bottle above the liquid level. When pressure is applied to the bottle body, the air is forced down through the riser pipe. At the same time, the liquid from the bottle is sucked into the chamber through the inlets due to the different pressure ratios during this process. Air and liquid are mixed in the pores of the open-cell foam material and the foam is discharged downwards as foam through the outlet opening.
When using the bottle in an upright position, foam is generated as follows:
The chamber having the porous body has one or more inlets that lie above the liquid level inside the bottle. The riser pipe, which is located at the base of the chamber in the upright position, extends to the base of the bottle. When pressure is applied to the bottle body, the liquid is forced upwards through the riser pipe, wherein the different pressure ratios during this process cause the air to be sucked in from the headspace of the bottle. Air and liquid are mixed together in the pores of the open-cell foam material and the resulting foam is discharged upwards out of the outlet opening.
In the case of the upright position, it is advantageous if the opening for the foam outlet is not directed vertically upwards, but the foam is discharged via a spout having a lateral direction.
Since the foam dispenser is hand-operated, the bottle is preferably a size that is easy to hold with one hand. The bottle has a volume of 50 ml to 500 ml, for example. Preferably, the bottle has a volume of 100 ml to 250 ml, in particular 100 ml to 150 ml.
In a bottle having a volume of less than 500 ml, the inlet for air preferably has a diameter of 1.0 mm to 1.4 mm. The inlet for liquid preferably has a diameter of 0.6 mm to 0.8 mm.
The ratio of the size of the inlet opening(s) for air to the size of the inlet opening(s) for liquid is preferably 1:0.9 to 1:1.5, particularly preferably 1:0.9 to 1:1.1. If the ratio of air inlets to liquid inlets is approximately 1:1, as in the last-mentioned preferred embodiment, the foam generation works both upside down and upright.
The ratio of the total size of air inlets and liquid inlets has an influence on foam generation. The diameter of the inlet opening for air must not be too large and the air content must not be too high, otherwise good foam will not be formed.
One embodiment of the foam-generating device is designed as an insert with a flange. The flange is placed on the upper edge of the bottle neck, with the closure cap attached to the neck of the bottle and holding the insert in place.
In one embodiment, the closure cap and foam-generating device are formed in one piece and the closure cap with the foam-generating device is attached to the neck of the bottle, preferably screwed on or crimped.
In one embodiment, the foam-generating device is designed as an insert which is snapped into the closure cap, glued to the closure cap or welded to the closure cap, wherein the closure cap is attached with the insert to a neck of the bottle, preferably screwed on or crimped.
The closure cap can have a conventional design and can, for example, comprise a hinged lid or a protective cap or be designed as a pull closure. It also usually has a fastening device with which it is attached to the neck of the bottle, e.g. a screw thread or a crimp closure.
The foam dispenser according to the invention can be designed as a disposable product for disposal after emptying the liquid or as a refillable reusable product. In a reusable product, both the alcoholic or non-alcoholic solution can be refillable and/or the porous body can be replaceable.
The foam dispenser according to the invention can be manufactured cost-effectively, since it is composed of only a few components. Thanks to the foam-generating device, foam can also be generated with alcoholic solutions and both with upside down and upright application. According to the invention, foam is generated using a hand-operated foam dispenser with few components. Due to the compact design without a motor, electrical parts or valves for control, cost-effective manufacture is possible and handling is easy, intuitive and trouble-free. An alcoholic disinfectant can be applied as a foam using the foam dispenser according to the invention. Due to its consistency, foam has the advantage of being easier to dose and distribute than liquids. While a liquid hand sanitizer, for example, flows quickly from the hand when it is dispensed and thus not only gets on the hand but also on the floor, foam flows more slowly and can thus be spread more easily and drip-free on the hands.
Another object of the invention is the use of a foam dispenser according to the invention for foaming an alcoholic solution, preferably an alcoholic disinfectant.
Another object of the invention is a method for foaming an alcoholic solution, preferably an alcoholic disinfectant, comprising the steps of
To determine the density of the uncompressed foam, first the outer dimensions of a foam material sample are measured and the volume is calculated from the outer dimensions. The weight of the foam material sample is also determined and the density is calculated using the formula density=weight/volume. The density of the uncompressed foam material is thus determined in accordance with the ISO 845 (g/cm3) or ASTM D 3574-11A (lb/ft3) standards. If the porous body in the chamber of the foam dispenser is compressed, the density increases accordingly by the degree of compression. To calculate the density, reference is made in the present case to the volume that the porous body has in the chamber when in the compressed state.
The number of pores is determined microscopically. For this purpose, a straight line is made along one surface of the foam material and the number of pores along this line is counted over a distance of 1 inch.
The pore size is determined in accordance with ASTM D 3576-2004. For this purpose, a thin layer of foam material of a defined size is cut and placed in a special projector. The projector projects the sample together with a reference line. The length of the reference line is specified in millimeters. The number of cells that are intersected by the reference line is counted. The mean pore size is calculated from the length of the reference line and the number of pores.
The invention is explained in more detail with reference to the Figures. The Figures show:
In all the embodiments shown, the side wall of the chamber can have further inlets that are located outside the sectional plane and are thus not shown.
A foam dispenser with a bottle size with a capacity of 100 ml and a structure similar to that shown in
Different embodiments of the foam dispenser were filled with different solutions, a high-alcohol solution, a low-alcohol solution and an aqueous cleaning formulation, in order to investigate foam generation, particularly with a high alcohol content of the foamable solution. The tested solutions had the following compositions:
Foam generation tests were carried out by turning the foam dispenser upside down and squeezing the bottle by hand until foam or liquid came out of the dispensing opening. The foam quality was assessed visually and haptically. The following values between 1 and 10 were assigned:
Table 1 in the appendix summarizes the foam generation tests carried out and the evaluation of the foam quality. It can be seen that a stable foam can be produced with the foam dispenser according to the invention even with a high alcohol content of 80% by weight (foam quality value>5). The tested aqueous soap formulation without alcohol produced a very firm foam with high stability.
The invention is not limited to one of the embodiments described above, but can be modified in a variety of ways.
| Number | Date | Country | Kind |
|---|---|---|---|
| 21217300.9 | Dec 2021 | EP | regional |
The present application is a national stage application of International Application No. PCT/EP2022/083475, filed Nov. 28, 2022, which claims priority to European Patent Application No. 21217300.9, filed Dec. 23, 2021, the entire contents of which are incorporated herein by reference in their entirety.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2022/083475 | 11/28/2022 | WO |
