The present invention relates to a device for applying a laundry composition to a fabric.

WO 2017/067851 discloses an applicator device for releasing fluid detergent to a surface, comprising a container to house fluid detergent composition and a fluid release system housed in the container. The fluid release system comprises a plunger having a top and a base and a resilience member, wherein the plunger base is provided with at least one seal knob that operably mates with a corresponding fluid release port on one face of the container and the top of the plunger opens into an air chamber located in the wall of the container.

WO 2018/091264 discloses a device for applying a fluid to a surface, comprising a container with first and second sides defining substantially planar surfaces, the second side with a dispensing opening, a compartment for housing a fluid and one or more extension members on the second side for contacting the surface when the device is in use. The device further comprises a fluid release system for dispensing the fluid from the second side with a plunger comprising a base operably mated with the dispensing opening, a resilience member, and a top which projects into an air chamber for allowing air into the compartment when fluid is released. The one or more extension members are configured such that the dispensing opening is located at a height of at least 3.5 mm from the surface when the one or more extension members contact the surface.

WO 2019/129461 discloses a device for dispensing a liquid detergent, comprising a reservoir configured to hold a liquid detergent, a liquid bellows in fluid communication with the reservoir via a first one-way valve configured to allow liquid to move from the reservoir to the liquid bellows. The liquid bellows is configured to expel liquid contained in the bellows into a mixing chamber. A compressible air chamber is also provided with an outlet through which air can be expelled into the mixing chamber upon collapse of the air chamber. An actuator is provided for compressing the air and liquid chambers and includes at least one dispensing aperture through which a detergent air mixture e.g. foam can be dispensed.

Despite the prior art there is a need for improved devices for applying liquid detergent to fabric. In particular, there is a need for devices with improved dispensing mechanism, which enables controlled dispensing of a liquid detergent with ease of use. Accordingly, and in a first aspect, there is provided a device for applying a liquid detergent to a fabric, the device comprising a detergent tank for containing the liquid detergent and an application surface for contacting the fabric in use and comprising an outlet disposed thereon such that liquid detergent is dispensed through the application surface onto the fabric, said device comprising a first and second unit dose dispenser between said tank and said application surface and wherein said first and second unit dose dispensers are disposed on opposing ends of a rocking member such that when the device is compressed and pushed in a first direction by the user the first unit dose dispenser expels a unit dose of liquid detergent while the second unit dose dispenser is filled from the liquid detergent tank and when the device is compressed and pushed in a second direction, substantially opposite the first direction, the second unit dose dispenser expels a unit dose of liquid detergent while the first unit dose dispenser is filled.

In use, a consumer compresses and rubs an applicator device against a fabric thereby dispensing a liquid detergent and applying it to the fabric. This simulates a conventional detergent bar application on the fabric. The amount of the liquid detergent dispensed, or the dosage of the liquid detergent depends on the pressure applied during compression of the device. Often it is observed that the dosage varies with factors, such as, duration of compression, applied pressure by different consumers etc. Thus, the performance of the device also varies accordingly. One way to achieve better control over the dosage is to incorporate a unit dose dispenser in the device. Typically, a unit dose dispenser dispenses a known amount on every compression and refill on subsequent relaxation. Consequently, the consumer needs to sequentially compress and relax while rubbing the device in use, which is a tiresome exercise for the consumer. Therefore, it is desirable to have a device with improved dispensing mechanism, which enables controlled dispensing of a liquid detergent with ease of use.

We have surprisingly found that a rocking dispensing assembly provides improved dispensing control during rubbing of a so called ‘liquid in bar’ arrangement where a bar shaped device is used to house a liquid detergent and where compression of the device against the fabric during use causes liquid to be dispensed.

The rocking member permits asymmetric application of detergent to the fabric during use. When one end of the device is compressed the unit dose dispenser on that side, dispenses detergent; conversely the opposite end is relaxed, and the corresponding unit dose dispenser fills with liquid drawn from the tank.

The rocking member preferably comprises a pivot about which it rocks during use. It is also found that the device according to embodiments of the invention the liquid detergent is dispensed only when the device is rubbed along a particular direction, for example, along a general longitudinal axis of the device. When sufficient liquid detergent has been used the device is merely scrubbed in a direction substantially orthogonal to the longitudinal axis instead.

The device according to the invention comprises a detergent tank for containing a liquid detergent. The detergent tank preferably comprises a pressure equalising valve which allows air into the detergent tank when the liquid detergent is disposed from the detergent tank to the unit dose dispenser.

Detergent liquids are well known in the art and any of those commercially available may be used in a device according to the invention. Preferably, the device comprises liquid detergent in the tank. More preferably, such liquid detergent has a viscosity of from 10 to 4000 centipoise.

The device comprises an application surface for contacting the fabric in use and through which detergent is dispensed onto the fabric. The detergent tank is thus in fluid communication with the outlet disposed on the application surface.

The unit dose dispenser is disposed such that when the device is compressed by the user during use the detergent tank is compressed against the fabric from above, i.e. the device is compressed between the user’s hand and a supporting surface beneath the fabric. Preferably, the unit dose dispenser forms a unit dose chamber defined by a resilient wall, for example as might be provided by an elastomeric sleeve or a bellows.

Preferably, the liquid detergent tank comprises a pressure equalizing valve located on a wall of the tank. In another embodiment, the pressure equalising valve may be disposed inside a secondary compartment attached to the detergent tank. Preferably the pressure equalising valve comprises a one-way valve which allows air into the detergent tank and block the liquid detergent to spill out from the tank.

Preferably, the unit dose dispenser comprises a pair of one-way valves oriented to permit liquid to flow from the detergent tank towards the outlet on the application surface. This is referred to as a flow direction. The one-way valves thus prevent liquid from flowing in an opposite direction to the flow direction. Thus, as the tank is compressed against the fabric, the unit dose dispensers are subjected to a positive air pressure. If the device is being used for the first time the unit dose dispensers) is/are empty and so this merely results in the air being expelled from inside the unit dose dispenser(s). However, when the downward pressure is released the pressure inside the unit dose dispensers) is/are reduced such that a negative air pressure results. This draws in liquid detergent from the tank and through the first one-way valve into the unit dose dispenser(s). The following time the device is compressed, the positive pressure exerted on the unit dose dispenser(s) cause the contents to be dispensed out through the outlet(s) and onto the fabric.

Preferably, the device comprises a biased resilient means for maintaining the device in a relaxed position in which there is no pressure exerted on the unit dose dispenser(s) and the tank remains at its most distant from the application surface.

Preferably, the biased resilient means is a spring or other such device, for example, a resilient member and which is squashed or compressed when pressure is applied to the top of the device and the opposing top and bottom surfaces are urged towards one another.

In a preferred embodiment the biased resilient means is in the form of a bellows. In an alternative embodiment the biased resilient means is in the form of a plunger which fits snugly within a cylinder so that air pressure maintains the device in a relaxed position.

Preferably the detergent tank comprises a substantially rigid outer shell. The rigid shell provides structural strength to the device for containing the liquid detergent in it. It also helps in gripping the device while in use and it is preferred that the outer shell is shaped and dimensioned so as to resemble a bar of soap. This not only allows easy handling by the user but also helps reassure the user who is used to using bars of soap to clean clothes that the liquid in bar product functions in a similar manner.

The shell may be made by moulding polymeric materials selected form polypropylene, polyethylene, polycarbonates etc. and blends thereof. Apart from these examples, any polymeric material used as rigid packaging material for laundry liquid is suitable for the purpose of the invention.

Preferably the detergent tank comprises an opening sealable with a cap for filling the tank with liquid detergent. The device is designed for multiple use. To achieve this the detergent tank is sufficiently dimensioned to hold enough liquid detergent for multiple uses. In another aspect the detergent tank is refillable such that when the detergent tank is empty, the user removes the cap and fills the detergent tank with the liquid detergent and reapplies the cap.

Preferably the application surface is roughened. The roughened surface allows the user to generate more foam more quickly in use compare to a smooth surface.

The unit dose dispenser directs the flow of the liquid detergent from the detergent tank to the applicator and expelling a unit dose of the liquid detergent during use. A unit dose is a predefined dose of liquid detergent to be dispensed per use. Preferably the unit dose dispenser or dispensers are dimensioned such that a single or combined dose equates with from 0.1 to 0.5g of liquid detergent.

Preferably the unit dose dispenser comprises a bellows for providing resilience during use of the device. The bellows also helps in flowing of the liquid detergent in the unit dose dispenser. During use, when the bellows expands the unit dose dispenser fills with the liquid detergent from the detergent tank and when the bellows compresses the unit dose dispenser expels the liquid detergent through the outlet.

Preferably the outlet comprises a one-way valve for allowing the detergent to flow through the application surface and blocking the immediate flow of external fluid back into the device.

According to a second aspect, there is provided a method for treating a fabric comprising taking a device according to the first aspect placing the device onto the fabric, compressing the device to dispense the liquid detergent onto the fabric and agitating the liquid detergent on the fabric.

Embodiments of the invention will now be described with reference to the following non-limiting example in which Figure 1 is a cross section of a detergent applicator.

The liquid in bar device (1) has a detergent tank (6) for containing and storing the liquid detergent. The detergent tank (6) is filled through a sealable opening (3) which is closed by a cap (4) which mates with a screw thread (5) on the top of the detergent tank wall (2).

The device (1) also has a pair of opposing lower chambers which act as a unit dose dispenser (7) each of which has a one-way valve as an inlet (16) and another one-way valve as an outlet (12). Both one-way valves are formed from a resilient seal (11) which flexes on application of pressure from one side to open the valve and yet does not open on pressure from the opposite side. The unit dose dispenser (7) is defined also by a resilient sleeve in the form of a bellows means (15).

The device (1) also has a flat plate (8) on the bottom of the device (1) and which has an application surface (9) which is used to rub against the fabric to clean it during use.

The flat pate (8) is maintained apart from the base (17) of the reservoir by a rocking member formed around a pivot (22) and about which is connected a pair of opposing arms one connected to the detergent tank base (17) and the other connected to the flat plate (8). This permits the flat plate (8) to move towards and away from the base (17) of the detergent tank depending which side of the pivot pressure applied.

The gap (14) between the flat plate (8) and the base (17) of the detergent tank (6) permits relative motion between the two by acting as a pressure equalizing orifice. Air thus passes in and out of the gap (14) as the plate and detergent tank (6) are compressed against one another during use. The baffle (13) prevents liquid from the exterior from entering the space between the base (17) and the plate (8). The flat plate (8) also has a roughened layer (9) for increasing cleaning capability as the plate (8) is rubbed over the fabric during use.

To use, the consumer places the device (1) on an item of fabric (not shown) and applies pressure from the top (2). This pressure exerts a positive pressure on the base of the device and when the device is moved in direction (A) squeezes the unit such that the unit dose dispenser (7a) is compressed between the flat plate (8) and the base (17). Simultaneously, the other unit dose dispenser (7b) is stretched so that the negative pressure created draws liquid into the chamber (7b) from the detergent tank (6). The unit dose dispenser (7) is shaped by a bellows means (15) which therefore determines the maximum unit dose size.

Further, when positive pressure is applied to unit dose dispenser (7a) the contents of the unit dose dispenser (7a) are squeezed out through the one-way valve (12) and onto the fabric.

When the device is moved in direction (B), the opposite occurs in that unit dose dispenser (7a) becomes relaxed and so fills, while unit dose dispenser (7b) is compressed and any liquid contained therein is expelled through the one-way valve and onto the fabric.

Figure 2 shows a view of the underside of the device embodied in figure 1. Shown in the figure is the flat base (8) and the application surface (9) to provide improved agitation during rubbing. Also shown is the resilient seal (11) and the dispensing orifice (12) through which liquid detergent is dispensed.

Figure 3 is a side elevation of the same embodiment. Shown is the screw cap (4) for closing the detergent tank and the application surface (9) on the flat plate (8) forming the bottom of the device. Figure 4 is a plan view of the same embodiment showing the screw cap (4) and the top surface (2) on which pressure is applied by the user using use.