GB2542337A

GB2542337A - A method of manufacturing a liquid receptacle

Info

Publication number: GB2542337A
Application number: GB1516006.2A
Authority: GB
Inventors: Khan Fuad
Original assignee: Hpc Healthline UK Ltd
Current assignee: Hpc Healthline UK Ltd
Priority date: 2015-09-09
Filing date: 2015-09-09
Publication date: 2017-03-22
Anticipated expiration: 2035-09-09
Also published as: GB2542337B; GB201516006D0

Abstract

A method of manufacturing a liquid receptacle comprises applying an adhesive to the inner surface 10 of a liquid receptacle 1 and dispensing a liquid absorbent material 24 from an applicator 12 onto the liquid receptacle 1 while moving the receptacle. The dispensed liquid absorbing material is applied across a selected region of the inner surface 12 and in particular to the region to which the adhesive is applied. Movement may be controlled so that the absorbing material 24 is applied in a layer having a single granule depth. The applicator 12 may comprise a rotating shaft 16 which acquires absorbent material onto its surface and dispenses it in a downwardly moving curtain. The applicator may be arranged to dispense the liquid absorbing material in a row, and the receptacle may be moved in a direction orthogonal to the length of the row. A conveyor 26 may move the receptacle. Preferably the receptacle 1 is formed from a pulp fibre material and the liquid absorbing material is a granular super absorbent polymer. The disposable receptacle may be a bedpan or urinal.

Description

A METHOD OF MANUFACTURING A LIQUID RECEPTACLE

The present invention relates to a method of manufacturing a liquid receptacle including a liquid absorbing material, and in particular to a method of forming a disposable receptacle such as a bedpan or urinal formed from moulded pulp fibre having a liquid absorbing material provided on the surface thereof.

Liquid receptacles are widely used through the healthcare industry. Bedpans and other toileting receptacles such as urinals, slipper pans, potties and commode pans are used in hospitals for toileting bedridden or infirm patients. Other receptacles such as washbowls and kidney trays are also commonly and frequently used. Such receptacles, and in particular bedpans and other toileting receptacles, were conventionally reusable receptacles formed from metal or moulded plastic. More recently the advantages of disposable receptacles have been recognised. Disposable receptacles and commonly manufactured from moulded pulp fibre, which is a low cost and easily disposable material. The use of single-use disposable receptacles obviates the requirement to clean and sterilise the receptacles after use. It has been identified that reusable receptacles are not consistently cleaned to an acceptable standard, leading to the spread of infection. For this reason, disposable receptacles are now promoted as best practice in infection control.

The transportation of liquid receptacles that contain liquid after use is problematic in a healthcare environment due to the risk of spilling the contents en route to the sluice room. This is a particular problem where the receptacle contains urine and/or faecal matter. Aerosolisation of pathogens, which may for example occur when carrying an open bedpan through a ward, is attributed to a high number of hospital-acquired infections, such infections having high morbidity and mortality rates. It is therefore highly desirable to ensure that disposable liquid receptacles mitigate the risk of airborne transmission, while still allowing for low cost manufacture that is essential for single use products within the healthcare industry.

Furthermore, many toileting receptacles are used by a patient while remaining in bed.

Use of these products on an unstable surface such as a mattress can leads to spills. In addition to causing embarrassment for the user, such spills cost time and money in terms of bed change, patient shower, and new linen, which is a huge hidden cost in using items of this type.

It is known within the healthcare industry to place a sachet of absorbent gel material such as granules of superabsorbent polymer (SAP) into a liquid receptacle to absorb liquid within the container, and therefore minimise or prevent the risk of spillage and aerosolisation. Post-use, the gel may be cleaned from the receptacle allowing reuse, or in the case of single use receptacles disposed of with the receptacle. While desirable for reusable receptacles, the use of sachets with disposable containers undesirably increases the cost of the container. Furthermore, it has been found that constraining the gel within a sachet leads to an inefficient and non-uniform absorption within the container. The use of sachets and other insertable products also risks the insert not being present with the container at the point of use, or falling from the container before full absorption has occurred. In addition, by using an arbitrary amount of gel, as in a sachet, for different vessels and needs leads to an excess of gel or sometimes not enough gel. Excess gel is not beneficial to macerators and pipe work and not enough gel does not provide the desired safety against spillage.

It is therefore desirable to provide an improved method of manufacturing of a liquid receptacle which addresses the above described problems and/or which offers improvements generally.

According to the present invention there is provided a method manufacturing a liquid receptacle as described in the accompanying claims.

In an embodiment of the invention there is provided a method of manufacture of a liquid receptacle, the method comprising the steps of: providing a liquid receptacle; applying an adhesive to the inner surface of the liquid receptacle; dispensing a liquid absorbent material from an applicator onto liquid receptacle; and moving the liquid receptacle relative to the applicator such that the dispensed liquid absorbing material is applied across a selected region of the inner surface.

Applying the liquid absorbing material in a controlled manner in which the receptacle is moved relative to an applicator allows the area to which the material is applied to be accurately controlled and applying the material to a predetermined region ensures that the absorbent material is used in an economical manner. Applying and adhering the absorbent material directly to the surface of the receptacle in this manner provides a receptacle with an integrated absorbent layer arranged across the predetermined absorbency region. This avoids the need for providing the absorbent material separately, as well as enabling a more efficient and better performing absorption. The selected region may be on the base of the receptacle.

The adhesive is preferably applied to a predefined region on the inner surface of the liquid receptacle and the liquid absorbent material is dispensed from the applicator onto the predefined region at a first end and the receptacle is moved relative to the applicator such that the dispensed liquid absorbing material is applied across the predefined region to a second end. The adhesive and the absorbent material are therefore applied only to the region in which they are required. Therefore by controlling the amount of gel adhered to a receptacle, one can match the gel's absorbent capacity to capacity of the vessel, ensuring that only the amount of gel required is used. This avoids the problem of excess gel fouling macerators.

The liquid receptacle is preferably a disposable liquid receptacle formed from a pulp fibre material. The liquid absorbing material is preferably a granular super absorbent polymer.

The applicator may be arranged to dispense the liquid absorbing material in a row and the liquid receptacle is moved relative to the applicator in a direction orthogonal to the length of the row.

Preferably the liquid receptacle is placed on a conveyor and the conveyor moves the receptacle relative to the applicator. The conveyor allows for accurate control of the movement of the receptacle.

The applicator preferably comprises a rotating shaft arranged to acquire liquid absorbing material onto its surface from within the applicator and dispense the liquid absorbing material in a downwardly moving curtain.

Rotation of the shaft may be controlled to apply liquid absorbing material only to the predefined region. The commencement and cessation of rotation defines the start and stop points of the application of the liquid absorbing material.

The liquid absorbing material may be a granular material and the surface of the shaft is configured to dispense the liquid absorbing material in a single row such that the curtain has a depth of only one granule. The surface configuration may be formed by knurling or otherwise. Preferably the shaft picks up granular material fed to the shaft from a hopper above the shaft.

The speed at which the liquid receptacle moves relative to the applicator may be controlled to ensure the liquid absorbing material is applied to the receptacle in a layer having a single granule depth. For a given speed of application of the granular material, increasing the speed of the conveyor decreases the density and vice versa.

The speed at which the liquid receptacle moves relative to the applicator is controlled to ensure the liquid absorbing material is applied across the receptacle in a uniform density layer. Uniform density is achieved if the speed of the conveyor is constant relative to the speed of application, i.e. the speed of rotation of the shaft.

The rotation speed of the shaft may be controlled to ensure the liquid absorbing material is applied to the receptacle in a layer having a single granule depth. The rate at which the rows of granules are supplied is selected to ensure rows of granules do not deposit on top of each other.

The rotation speed of the shaft may be controlled to ensure the liquid absorbing material is applied to the receptacle in a uniform density layer.

According to another aspect of the present invention there is provided a liquid receptacle having a layer of liquid absorbing material adhered directly to at least a region of the inner surface of the receptacle. The term 'directly' includes an arrangement in which the material is adhered by a liquid adhesive applied to the surface, but also includes an arrangement in which bonding is effected via an adhesive substrate such as an adhesive film bonded to the surface between the liquid absorbing layer and the surface. The liquid absorbing material is preferably a super absorbent material (SAP) adhered to the inner surface. Adhering the absorbent material directly to the surface of the receptacle provides a receptacle with an integrated absorbent layer, which avoids the need for providing the absorbent material separately, as well as enabling a more efficient absorption. This ensures that the absorbent material is always present at the point of use. In addition, the use of a thin, uniformly applied layer enables a more economical use of the absorbent material than, for example, the use of a sachet of such material, as well as increasing the absorbency efficiency of the material.

Preferably the SAP is a granular material and the layer of SAP has a single granule depth. Preferably the SAP layer has a uniform density.

The receptacle may be formed of a moulded pulp fibre material.

The present invention will now be described by way of example only with reference to the following illustrative figures in which:

Figure 1 shows the application of a layer of super absorbent polymer to a liquid receptacle in according with an embodiment of the present invention.

Referring to Figure 1, a disposable liquid receptacle 1 includes a base 2 and a plurality of side walls 4 defining a liquid containing volume 6. An opening 8 to the receptacle 1 is formed at the upper edge of the walls 4. The liquid receptacle 1 is formed from a moulded pulp fibre preferably including a sizing agent which waterproofs the material. In other embodiments of the invention the receptacle may be formed from any suitable disposable material. The receptacle 1 may be a moulded or otherwise pre-formed container, but in other embodiments may be a sheet of material formed as a blank that may be formed at the point of use of otherwise into a receptacle through a series of folds or other forming operations. For example, the receptacle may be a cardboard blank having a series of fold lines that is formed into a receptacle at the point of use.

The receptacle 1 includes an inner surface 10. An absorbent material such as a Super Absorbent Polymer (SAP) is applied and bonded directly to the inner surface of the receptacle 1 to absorb liquid introduced into the receptacle. Preferably the absorbent material comprises SAP granules. A process is described for the application of the SAP granules to the receptacle. A predefined region within the receptacle is determined to which the SAP granules are to be applied. The shape, size and location of the region will vary depending on the shape, size and application of the receptacle. In the receptacle 1 of Figure 1, the predefined region is on the upwardly facing inner surface of the base 2. An adhesive is applied to the predetermined region. The adhesive may be applied by spraying, rolling, printing or any other suitable means. Alternatively the adhesive may be a preformed adhesive substrate, such as a double sided adhesive sheet, that is applied to the predefined region. The adhesive is preferably a liquid adhesive, and is further preferably a solvent based adhesive which prevents the adhesive from becoming unbonded from the receptacle 1 by the liquid. Alternatively the adhesive may be a liquid adhesive such as Polyvinyl Acetate (PVA).

An applicator 12 is provided for applying the SAP granules to the predefined region once the adhesive has been applied. The adhesive may be applied to the receptacle 1 immediately preceding application of the SAP granules, or at some preceding time. For example, in the case of an adhesive substrate, the substrate may be adhered to the receptacle 1 some time prior to the application process and may include a release sheet that is removed immediately preceding SAP granule application. The applicator 12 includes a hopper 14 that contains the SAP granules. A roller 16 is provided at the lower outlet 18 of the hopper 14. The roller 16 comprises a cylindrical shaft having a series of small ridges and indentations along its outer surface formed for example by knurling.

The knurled shaft 16 is arranged to rotate at the base of the hopper 14. As the SAP granules 20 at the base of the hopper 14 come into contact with the shaft 16 the ridges of the knurled shaft 16 pick up the granules and carry them across an arc of rotation. The knurling may be precisely configured to enable the shaft 16 to pick up very accurate amounts of granules. The shaft 16 rotates away from the base of the hopper 14 carrying the granules towards the outlet 22 of the applicator 12. At the point of rotation where the tangent of the surface of the shaft 16 is substantially vertical, the granules fall away from the shaft 16 downwardly towards the outlet 22. The shaft 16 is configured to cause the granules to fall away from the shaft 16 in a straight line arrangement a single granule deep, creating a curtain 24 formed from a single row of granules a single granule deep and having a length defined by the length of the shaft 16. Deflector plates are preferably at the feed outlet to prevent air currents from distorting the uniform pattern of material distribution.

The receptacle 1 is placed onto a conveyor 26. The adhesive may be applied to the receptacle 1 while it is on the conveyor 26. The conveyor 26 is arranged to move the receptacle linearly beneath the applicator 12 and to cause the receptacle to pass beneath the dispensing curtain 24 of SAP granules. The curtain of granules 24 is configured to correspond in width to the width of the preselected region on the upper surface of the base 2, and the conveyor 26 and receptacle 1 are arranged such that the direction of travel of the receptacle is parallel to the longitudinal direction of the predefined region, and such that the longitudinal direction is orthogonal to the length of the curtain of granules 24.

As the receptacle 1 passes beneath the curtain 24 the granules deposit onto the adhered surface in a uniform row, and as the receptacle 1 continues to move the row extends longitudinally forming a uniform layer 28. The length of the deposition layer 28 is determined by the speed of the conveyor 26 and the dispending period of the applicator. The density of the SAP granules may be varied by varying the rotation speed of the shaft 16 and/or by varying the speed of the conveyor 26. The density of the curtain 24 i.e. its granular depth and the number of granules along each row, may be varied by varying the configuration, spacing and depth of the grooves of the knurled shaft 16. This method of application therefore achieves a highly controllable application of the SAP granules to the predefined surface region of the receptacle 1. By maintaining the dispensing shaft 24 to a depth of 1 granule, and by controlling the application speed through varying the curtain speed and/or speed of the conveyor, the deposited layer of SAP may be applied at a layer depth of only 1 granule. The density of the deposited layer may also be optimised by controlling application speed through varying the shaft speed and/or speed of the conveyor. It has been found that absorption is most efficient for a uniform, single granule depth layer of high density. This also ensures that the SAP material is utilised in the most efficient manner possible thereby minimising material usage and minimising cost. By applying the material directly to only the predefined region, the method also avoids wastage by preventing the application of SAP granules to regions where adhesion is not required.

Whilst endeavouring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the

Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.

Claims

1. A method of manufacture of a liquid receptacle, the method comprising the steps of: providing a liquid receptacle; applying an adhesive to the inner surface of the liquid receptacle; dispensing a liquid absorbent material from an applicator onto the liquid receptacle; and moving the liquid receptacle relative to the applicator such that the dispensed liquid absorbing material is applied across a selected region of the inner surface.

2. A method according to claim 1 wherein the adhesive is applied to a predefined region on the inner surface of the liquid receptacle; the liquid absorbent material is dispensed from the applicator onto the predefined region at a first end and the receptacle is moved relative to the applicator such that the dispensed liquid absorbing material is applied across the predefined region to a second end.

3. A method according to claim 1 or 2 wherein the liquid receptacle is a disposable liquid receptacle formed from a pulp fibre material.

4. A method according to any preceding claim wherein the liquid absorbing material is a granular super absorbent polymer.

5. A method according any preceding claim wherein the applicator is arranged to dispense the liquid absorbing material in a row and the liquid receptacle is moved relative to the applicator in a direction orthogonal to the length of the row.

6. A method according to any preceding claim wherein the liquid receptacle is placed on a conveyor and the conveyor moves the receptacle relative to the applicator.

7. A method according to any preceding claim wherein the applicator comprises a rotating shaft arranged to acquire liquid absorbing material onto its surface from within the applicator and dispense the liquid absorbing material in a downwardly moving curtain.

8. A method according to claim 7 wherein rotation of the shaft is controlled to apply liquid absorbing material only to the predefined region.

9. A method according to claim 7 or 8 wherein the liquid absorbing material is a granular material and the surface of the shaft is configured to dispense the liquid absorbing material in a single row such that the curtain has a depth of only one granule.

10. A method according to claim 9 wherein the speed at which the liquid receptacle moves relative to the applicator is controlled to ensure the liquid absorbing material is applied to the receptacle in a layer having a single granule depth.

11. A method according to claim 9 wherein the speed at which the liquid receptacle moves relative to the applicator is controlled to ensure the liquid absorbing material is applied to the receptacle in a uniform density layer.

12. A method according to any one of claims 9 to 11 wherein the rotation speed of the shaft is controlled to ensure the liquid absorbing material is applied to the receptacle in a layer having a single granule depth.

13. A method according to claim 9 wherein the rotation speed of the shaft is controlled to ensure the liquid absorbing material is applied to the receptacle in a uniform density layer.