Ink cartridge and method of manufacture

The present invention relates to inkjet printing and more particularly to a cartridge for storing and dispensing ink, such as pigmented ink, for use with an inkjet printer, such as a continuous inkjet printer, an inkjet printer including the cartridge, and a method of manufacture of the cartridge.

In inkjet printing systems the print is made up of individual droplets of ink generated at a nozzle and propelled towards a substrate. There are two principal systems: drop on demand where ink droplets for printing are generated as and when required; and continuous inkjet printing in which droplets are continuously produced and only selected ones are directed towards the substrate, the others being recirculated to an ink supply.

Continuous inkjet printers supply pressurised ink to a print head drop generator where a continuous stream of ink emanating from a nozzle is broken up into individual regular drops by, for example, an oscillating piezoelectric element. The drops are directed past a charge electrode where they are selectively and separately given a predetermined charge before passing through a transverse electric field provided across a pair of deflection plates. Each charged drop is deflected by the field by an amount that is dependent on its charge magnitude before impinging on the substrate whereas the uncharged drops proceed without deflection and are collected at a gutter from where they are recirculated to the ink supply for reuse. The charged drops bypass the gutter and hit the substrate at a position determined by the charge on the drop and the position of the substrate relative to the print head. Typically the substrate is moved relative to the print head in one direction and the drops are deflected in a direction generally perpendicular thereto, although the deflection plates may be oriented at an inclination to the perpendicular to compensate for the speed of the substrate (the movement of the substrate relative to the print head between drops arriving means that a line of drops would otherwise not quite extend perpendicularly to the direction of movement of the substrate).

In continuous inkjet printing a character is printed from a matrix comprising a regular array of potential drop positions. Each matrix comprises a plurality of columns (strokes), each being defined by a line comprising a plurality of potential drop positions (e.g. seven) determined by the charge applied to the drops. Thus each usable drop is charged according to its intended position in the stroke. If a particular drop is not to be used then the drop is not charged and it is captured at the gutter for recirculation. This cycle repeats for all strokes in a matrix and then starts again for the next character matrix.

Ink is delivered under pressure to the print head by an ink supply system that is generally housed within a sealed compartment of a cabinet that includes a separate compartment for control circuitry and a user interface panel. The system includes a main pump that draws the ink from a tank of the ink supply system via a filter and delivers it under pressure to the print head. As ink is consumed the tank is refilled as necessary from a replaceable ink cartridge that is releasably connected to the tank by a supply conduit. The ink is fed from the tank via a flexible delivery conduit to the print head. The unused ink drops captured by the gutter are recirculated to the tank via a return conduit by a pump. The flow of ink in each of the conduits is generally controlled by solenoid valves and/or other like components.

As the ink circulates through the system, there is a tendency for it to thicken as a result of solvent evaporation, particularly in relation to the recirculated ink that has been exposed to air in its passage between the nozzle and the gutter. In order to compensate for this, “make-up” solvent is added to the ink as required from a replaceable solvent cartridge so as to maintain the ink viscosity within desired limits. This solvent may also be used for flushing components of the print head, such as the nozzle and the gutter, in a cleaning cycle. Therefore, a typical continuous inkjet printer has both a replaceable ink cartridge and a replaceable solvent cartridge. In this description, both ink cartridge and solvent cartridge are referred to as cartridges.

Various types of inks maybe used within the continuous inkjet printers. The ink may include an organic solvent selected from C1-C4 alcohols, C4-C8 ethers, C3-C6 ketones, C3-C6 esters, and mixtures thereof. Inks may contain different types of colourant. In some circumstances dye based inks are used. This may typically be the case where the substrate onto which printing is performed is relatively light in colour such that light reflected from the surface on which printing is to be performed is coloured by the dye contained within the ink resulting in a pattern visible to the user. On the other hand, where a surface on which printing is conducted is dark in colour, and therefore does not reflect much light, pigmented inks maybe preferred. In such the circumstances, the pigment contained within the ink may reflect certain colours of light, thereby ensuring that the printed image can be seen by a user. Of course, dye based, and pigmented inks may both be used for printing on some substrates, while pigmented inks may be used on light surfaces and, dye-based inks may be used on dark surfaces.

Where pigmented inks are used, the ink consists of a suspension of colourant (i.e. pigment) particles within a solvent. Various other components or additives (e.g. surfactants) may also be included within the composition of the ink. The ink composition may vary independence upon various characteristics, such as the colour required, the surface onto which printing is to be performed, solvents which are suitable for a particular application environment, and many other factors.

Inks may be required to be stored for extended periods of time. For example, it may be that a stock of ink is held which will be required to be used at any time, and which may need to be stored for several months before being used. Moreover, when an ink cartridge is installed within a printer, it may be that ink is withdrawn from the cartridge at various times. That is, it may be that ink is gradually withdrawn from the cartridge over an extended period of time, rather than being withdrawn within a single operation, or at a single time.

It will be understood, however, that during periods of extended storage, pigment particles, precipitates and other solid deposits can settle within a cartridge, forming a layer of sediment at the bottom surface of the cartridge. The sediment layer may be characterised by an extremely thick and viscous layer of ink which could cause blockages of ink supply pathways if it was to enter into the internal circuits of the printer. As such, printers using pigmented inks, and inks which may include precipitates and other solid deposits, tend to completely empty an ink cartridge when it is first installed, so as to avoid possible blockages (and associated problems). This results in printers for pigmented ink, and inks containing precipitates and other solid deposits being operated differently to printers for non-pigmented, precipitate-less (i.e. dye-based) inks. Alternatively, cartridges for pigmented inks and inks containing precipitates and solid deposits could be provided with a stirring device (e.g. a magnetic device), or some other form of disturbance mechanism (e.g. a fluid jet within the cartridge), which mixes ink within the cartridge once it has been installed in a printer. However, in either case, this will result in a more complex operation, and a printer and/or cartridge which must be operated differently to a printer for non-pigmented/precipitate-less inks. It is an object of the present invention, among others, to provide an improved cartridge for use with an inkjet printer (such as a continuous inkjet printer) which solves one or more problems, whether identified above or otherwise, of using pigmented inks, inks containing precipitates and/or solid deposits.

According to a first aspect disclosed herein there is provided a cartridge for storing and dispensing ink for use with an inkjet printer. The cartridge comprises a reservoir having at least one wall enclosing an internal space for storage of the ink, an outlet for dispensing the ink, the outlet provided at a base of the reservoir, and a sediment shield, the sediment shield having an aperture and defining an enclosed fluid communication path between the aperture and the outlet, the aperture being provided at a separation distance from the base of at least 5 millimetres.

The ink may be pigmented ink, and the at least one wall may define a volume for storage of the ink. The aperture may also be referred to as an opening or hole in the sediment shield. The sediment shield may be integrally formed with the cartridge. The sediment shield may be a separate member which is inserted into the reservoir of the cartridge.

In this way, the sediment shield is configured to prevent sediment (which may include pigment, precipitates and/or solid deposits) from reaching the outlet. In particular, while sediment may settle at the base of the reservoir when left for extended periods, the presence of a sediment shield, providing an enclosed fluid pathway, prevents sediment, or highly concentrated ink, or precipitates, or solid deposits, which may settle at the base of the reservoir, from being drawn into the outlet. The sediment may form a layer at the base of the reservoir that is several millimetres in thickness. As such, by proving an aperture further from the base than this distance, uptake of sediment can be minimised, thereby avoiding blockage of the outlet or an ink supply needle which is inserted through the outlet into the sediment shield.

The volume enclosed by the reservoir is substantially empty, except for ink. For example, there is no absorbent or porous member or materials provided within the reservoir to hold the ink. Such materials may interfere with the delivery of ink from the outlet, and may prevent proper emptying of the cartridge. The base may be defined as a side of the reservoir in which the outlet is provided, and from which ink is withdrawn. The base may be referred to as a base wall. When installed in a printer, the base may be located at the bottom of the reservoir, such that ink within the cartridge flows, under gravity, towards the base. Moreover, when stored for some time, pigment, or precipitates, or solid deposits within the ink may settle within the reservoir along an internal surface of the base.

Such sedimentation can result in the outlet becoming blocked. The shield may thus be configured to prevent sediment entering the outlet.

The sediment shield may be configured to restrict a sediment layer, which comprises pigment or precipitates within the ink and settles on an internal surface of the base, from reaching the outlet.

The cartridge may be configured such that ink can only pass from the reservoir to the outlet via the aperture. In other words, the only fluid communication path between the reservoir and the outlet includes passing through the aperture. This is advantageous, as it mitigates against any pigment, precipitates or solid deposits from reaching the outlet, especially if the orientation of the cartridge is changed after a prolonged period of time, where there may be a relatively large sediment layer. In embodiments, where the sediment shield comprises a plurality of apertures, the cartridge may be configured such that ink can only pass from the reservoir to the outlet via the plurality of apertures.

The sediment shield may comprise one or more apertures, each of the one or more apertures may be provided at a separation distance from the base of at least 5 millimetres. Ink may only pass from the reservoir to the outlet via the one or more apertures.

The sediment shield may comprise a barrier, and the barrier may be configured to block a vertical path between the outlet and the reservoir, when the cartridge is installed in a printer. That is to say, the sediment shield may comprise a closed end, the closed end being an end of the sediment shield which is furthest from the outlet of the cartridge.

The term “barrier may be configured to block” encompasses a solid wall or member, which does not permit the passage of fluid, pigment, precipitates or solid deposits. The term “barrier may be configured to block” also encompasses a member having a filter or mesh, or at least one small opening, which allows the passage of liquid, but would not permit the passage of pigment, particles or other solid deposits. This is in contrast to the, or each aperture, of the sediment shield, which may be sized such that liquid and pigment, precipitates or solid deposits would be able to pass through the, or each aperture. Although, it will be appreciated, that the, or each, aperture may be provided on an outer surface, in particular a side surface of the sediment shield, which mitigates against pigment, precipitates or solid deposits passing through the, or each aperture.

The barrier, in use, may be substantially horizontal relative to the length of the sediment shield, so as to prevent a vertical path from the reservoir to the outlet. The term “vertical path” encompasses a substantially straight pathway from a region of the reservoir that is axially above the outlet when the cartridge is installed in an inkjet printer. A vertical path, would be generally orthogonal to the barrier of the sediment shield.

The barrier may be integrally formed with the sediment shield, such that the sediment shield defines a closed end or closed top. In other embodiments, the barrier may be a cap, or an end closure, that is placed over the end of the sediment shield. In blocking a vertical fluid path, or in other words preventing fluid from the reservoir flowing through an end most region of the sediment shield further mitigates against pigment, precipitates or solid deposits from passing through the enclosed fluid communication path and reaching the outlet.

The, or each aperture may be provided on an elongate surface of the sediment shield. In other words, the, or each aperture, may be provided on an outer surface of the sediment shield which is not the closed or top surface. When the cartridge is in use, the elongate surface of the sediment shield is generally orthogonal to the base of the cartridge. In use, the elongate surface would be a generally vertical surface relative to the base of the cartridge. Although it will be appreciated that the elongate surface need not be strictly vertical. Providing the, or each aperture on the elongate surface of the sediment shield mitigates against pigment, precipitate or solid deposits from passing through the aperture and reaching the outlet compared to if the, or each aperture were provided on a horizontal surface of the sediment shield (such as the top surface). This is because if the, or each, aperture were provided on a top surface of the sediment shield, once pigment, precipitates or solid deposits are located above the aperture, they would fall through the aperture towards the aperture due to gravity. In contrast, any pigments, precipitates, or solid deposits which are located next to an aperture that is provided on a vertical (side) surface of the sediment shield, would fall towards the base of the cartridge, due to gravity, instead of passing through the aperture.

The sediment shield may be configured to maintain the separation distance between the aperture and the base as the ink is dispensed from the outlet.

This means that the sediment shield (in particular, its height) may not collapse as the ink level is lowered in the reservoir. The sediment shield may be made of a material that provides a sufficient rigidity, such that the sediment shield can maintain its shape without relying upon, for example, any floating force exerted by the ink.

The sediment shield may be configured to maintain a separation distance of at least 5 mm between the aperture and any wall of the reservoir, when the reservoir is full of ink.

In this way, sediment can be prevented from entering the aperture during periods of extended storage, even if a filled cartridge is stored without the “base” being the lowest part of the reservoir.

The cartridge may define a height from the base when the reservoir is full of ink, and the sediment shield may extend from the base less than 50% of the height of the cartridge. The height of cartridge, may be a length of the cartridge that is measured from the base of the cartridge to a distal wall or end of the cartridge which generally opposes the base of the cartridge. The height of the cartridge, may also be referred to as the overall length of the cartridge.

The sediment shield having a height which is less than 50% of the height of the cartridge ensures as much ink can be removed from the cartridge as possible (since the further the aperture is from the base, the more ink will remain in the cartridge when it is effectively “empty”). The sediment shield may have a height which is between around 10% and around 40% the height of the cartridge. The sediment shield may have a height which is between around 20% and 30% the height of the cartridge. The sediment shield may have a height which is between around 10% the height of the cartridge. The reservoir may comprise a top wall defining a surface opposite to the base. The reservoir may further comprise a plurality of side walls extending between the top wall and the base wall. The plurality of side walls may comprise a pair of opposed face walls, and a pair of opposed perimeter walls.

When the reservoir is full of ink, the initial internal volume of the reservoir, when in an un-deformed state, may be at least 50 % filled with ink. When the reservoir is full of ink, the face walls may be separated from one another. When the reservoir is empty, the face walls may deform so as to be in contact with one another, and also with the sediment shield.

The sediment shield may comprise at least one rib or protrusion, which extends from an outer surface of the sediment shield. Accordingly, the at least one rib or protrusion can maintain a separation distance between the outer surface of the sediment shield and a face wall of the cartridge when the reservoir is nearly empty. In doing so, the face walls are prevented from contacting the aperture of the sediment shield, and thereby allow remaining ink to leave the reservoir via the aperture.

The outlet may extend beyond the base. The outlet may extend at least 5 mm beyond the base in a direction opposite from the distance between the aperture and the base. As such, the aperture may be at least 10 mm from the outlet.

The sediment shield may comprise a tube which comprises the, or each, aperture and defines the enclosed fluid communication path between the aperture and the outlet. The tube may extend from the base into the reservoir. More specifically, the tube may extend from the outlet, past the base, and into the reservoir. The tube may be rigid.

The tube may comprise a bend. That is to say, that a centroid of the tube follows a curved path along a portion of the tube. In use, the bend in the tube may be provided in the reservoir of the cartridge. Providing a bend in the tube impedes movement of any pigment, precipitates or solid deposits which may have passed through the aperture and thereby further prevents pigment, precipitates or solid deposits from reaching the outlet. In embodiments where the tube comprises a bend, the separation distance between the aperture and the base is measured as an axial distance between the base and aperture, rather than the distance of the fluid path between the aperture and the base.

At least a portion of the tube may be flexible. In that it is meant that at least a portion of the tube can be elastically deformed, but will return to its original shape when a force which causes the tube to deform is removed. At least a portion of the tube being flexible may improve installation of the tube in cartridge, and in some embodiments may provide an improved seal between the tube and the outlet of the cartridge.

The, or each, aperture may be provided at a distance of at least 5 millimetres from a plane of the base at the location of the outlet.

The shield may comprise a central bore extending from the aperture to the outlet.

The shield may comprise an outlet opening configured to engage with the outlet. The outlet opening may comprise a hole. The outlet may be configured to receive a needle, to enable the ink to be withdrawn from the reservoir. The outlet may comprise a septum. The outlet opening may be configured to receive the needle inserted through the septum into the outlet.

The shield may comprise a plurality of apertures, each of the plurality of apertures being separated from the base at a separation distance of at least 5 millimetres.

The outlet opening may be provided at a first end of the shield. The aperture or the plurality of apertures may be provided at an opposite second end of the shield.

The plurality of apertures may be disposed around an outer surface of the shield.

The apertures may be evenly distributed around an outer surface of the shield. The apertures may be configured such that regardless of the orientation of the shield at least one aperture is facing at least partially, in each radial direction.

The shield may comprise four apertures disposed at 90 degrees from one another the outer surface of the shield. The aperture or apertures may be cross drilled.

The shield may comprise at least one groove extending along an outer surface of the shield from the base to the aperture.

The shield may comprise a plurality of apertures, and a corresponding plurality of grooves, each one of the plurality of grooves extended from the base to a respective one of the plurality of apertures. There may be four apertures and four grooves. The number of grooves may be less than the number of apertures. The shield may comprise a single groove.

The separation distance between the aperture and the base may be equal to or less than 25 millimetres. A maximum separation distance of 25mm between the aperture and the base ensures as much ink can be removed from the cartridge as possible (since the further the apertures are from the base, the more ink will remain in the cartridge when it is effectively “empty”). The maximum separation distance is in general a small percentage (e.g., less than 20%) of an overall length of the cartridge.

The, or each, aperture may a diameter equal to or greater than around 0.5 millimetres. The, or each, aperture may have a diameter less than or equal to around 4 millimetres. The, or each, aperture may have a diameter of around 2 millimetres

If the aperture is greater than around 4 millimetres in diameter, the risk of sediment (such as pigment, precipitates or other solid deposits) settling in the aperture and/or in an internal passage of the sediment shield may increase.

As the diameter of the aperture decreases, the rate at which ink in is able to leave the reservoir via the aperture is reduced. If the aperture is less than around 0.5 millimetres in diameter, the rate at which ink can leave the reservoir through the aperture may be too low for the rate of ink that is required by a printing system, which that cartridge is installed in. In other words, an aperture with a diameter less than around 0.5 millimetres is too restrictive to the flow of ink. The reservoir may be a collapsible reservoir. Walls defining the reservoir may be configured to collapse when the liquid is withdrawn from the reservoir. In general, such a reservoir does not have a venting hole, and the pressure within the reservoir is not allowed to equalise with the external environment. A negative pressure is typically maintained in the internal space of the collapsible reservoir.

The cartridge may be adapted to prevent air from entering the internal space from outside of the cartridge as the liquid is dispensed from the outlet.

The reservoir may comprise a single fluid port. The single fluid port may comprise the outlet. No air vent, or other equalisation vent, may be provided. Such a configuration will result in the pressure gradually reducing within the cartridge as ink is removed, causing the reservoir to collapse.

There is also provided an inkjet printer comprising a cartridge according to the first aspect, and a fluid connector for engaging with the outlet of the cartridge configured to receive ink from the cartridge.

According to a second aspect disclosed herein there is provided a method of manufacturing a cartridge according to the first aspect. The method comprises providing said reservoir having at least one wall enclosing an internal space for storage of the pigmented ink, and said outlet for dispensing the pigmented ink, the outlet being provided at a base of the reservoir; providing a sediment shield, the sediment shield having said aperture and an outlet opening for engagement with the outlet of the cartridge, the sediment shield defining an enclosed fluid communication path between the aperture and the outlet opening; and assembling the cartridge by arranging the sediment shield and the cartridge such that the outlet opening of the sediment shield is engaged with the outlet of the cartridge so as to define said enclosed fluid communication path between the aperture and the outlet.

Said assembling the cartridge by arranging the sediment shield and the cartridge may comprise inserting the sediment shield through the outlet of the cartridge. The sediment shield may be secured by an interference fit. The method may further comprise, before inserting the sediment shield through the outlet of the cartridge, filling the cartridge with pigmented ink.

The method may further comprise, after inserting the sediment shield through the outlet of the cartridge, closing the cartridge with a seal. The seal may comprise a septum.

According to a third aspect there is provided a sediment shield for installation in a cartridge for storing and dispensing pigmented ink for use with an inkjet printer, the cartridge comprising a reservoir having at least one wall enclosing an internal space for storage of the pigmented ink, and an outlet for dispensing the pigmented ink, the outlet being provided at a base of the reservoir. The sediment shield has an aperture and an outlet opening for engagement with the outlet of the cartridge, the sediment shield defining an enclosed fluid communication path between the aperture and the outlet opening. The sediment shield is configured such that, when engaged with the outlet of the cartridge, an enclosed fluid communication path is provided between the aperture and the outlet, and the aperture is provided at a separation distance from the base of at least 5 millimetres.

There is also provided a computer program comprising computer executable instructions that, when executed by a processor, cause the processor to control an additive manufacturing apparatus to manufacture a sediment shield described herein.

According to a further aspect of the present disclosure, there is provided a method of manufacturing a product via additive manufacturing, the method comprising: obtaining an electronic file representing a geometry of a product wherein the product is a sediment shield according to the third aspect; and controlling an additive manufacturing apparatus to manufacture, over one or more additive manufacturing steps, the product according to the geometry specified in the electronic file.

According to a further aspect of the invention, there is provided a method for storing and dispensing ink from a cartridge for use with an inkjet printer. The method comprising: storing the ink in a reservoir of the cartridge, and dispensing the ink from an outlet of the cartridge. Where dispensing the ink from the outlet of the cartridge comprises: withdrawing a volume of ink from the reservoir through an aperture, wherein when the cartridge is installed in an inkjet printer, the aperture is provided above a layer of sediment in the ink; and dispensing the volume of ink through the outlet of the cartridge.

The volume of ink withdrawn from the reservoir may pass through an enclosed fluid communication path between the aperture and the outlet.

Withdrawing the volume of ink through the aperture may substantially prevent precipitates in the reservoir from reaching the outlet of the cartridge. Precipitates, may include pigment and other solid deposits in the cartridge.

A separation distance between the aperture and any wall of the reservoir may be maintained during withdrawing a volume of ink from the reservoir. That is to say, a gap between the aperture and any wall which may define a reservoir as ink is withdrawn from the reservoir.

The volume of ink may be withdrawn from the reservoir through a plurality of apertures. The plurality of apertures may be spaced in the reservoir to prevent sediment from reaching the outlet. In other words, each of the apertures may be spaced at a distance from the base of the wall so as to prevent sediment, precipitates or solid deposits in the sediment layer from reaching the aperture.

Dispensing the ink from the reservoir may include collapsing the reservoir. In particular, walls defining the reservoir may be configured to collapse when the liquid is withdrawn from the reservoir.

According to a further aspect of the invention, there is provided a method for storing and dispensing ink from a cartridge for use with an inkjet printer. The method comprising: storing the ink in a reservoir of the cartridge and dispensing the ink from an outlet of the cartridge. Where dispensing the ink from the outlet of the cartridge comprises: withdrawing a volume of ink from the reservoir through an aperture provided at a separation distance of at least 5 millimetres from a base of the cartridge; and dispensing the volume of ink through the outlet of the cartridge.

The volume of ink withdrawn from the reservoir may pass through an enclosed fluid communication path between the aperture and the outlet. Withdrawing the volume of ink through the aperture may substantially prevent precipitates in the reservoir from reaching the outlet of the cartridge. Precipitates, may include pigment and other solid deposits in the cartridge.

A separation distance between the aperture and any wall of the reservoir may be maintained during withdrawing a volume of ink from the reservoir. That is to say, a gap between the aperture and any wall which may define a reservoir as ink is withdrawn from the reservoir.

The method may further comprise, maintain during withdrawing a volume of the ink from the reservoir, a separation distance between the aperture and any wall of the reservoir.

The volume of ink may be withdrawn from the reservoir through a plurality of apertures. The plurality of apertures may be spaced in the reservoir to prevent sediment from reaching the outlet. In other words, each of the apertures may be spaced at a distance from the base of the wall so as to prevent sediment, precipitates or solid deposits in the sediment layer from reaching the aperture.

Dispensing the ink from the reservoir may include collapsing the reservoir. In particular walls defining the reservoir may be configured to collapse when the liquid is withdrawn from the reservoir.

According to yet a further aspect of the invention there is provided a cartridge for storing and dispensing ink for use with an inkjet printer. The cartridge comprising a reservoir having at least one wall defining a volume for storage of the ink, an outlet for dispensing the ink, where the outlet is provided at a base of the reservoir; and a sediment shield. The sediment shield having an opening and defining an enclosed fluid communication path between the opening and the outlet, the opening being provided above a layer of sediment in the ink.

The ink may be pigmented ink. In this way, the sediment shield is configured to prevent sediment (which may include pigment, precipitates and/or solid deposits) from reaching the outlet. In particular, while sediment may settle at the base of the reservoir when left for extended periods, the presence of a sediment shield, providing an enclosed fluid pathway, prevents sediment, or highly concentrated ink, or precipitates, or solid deposits, which may settle at the base of the reservoir, from being drawn into the outlet. The sediment may form a layer at the base of the reservoir that is several millimetres in thickness. As such, by providing an opening above a sediment layer, uptake of sediment can be minimised, thereby avoiding blockage of the outlet or an ink supply needle which is inserted through the outlet into the sediment shield.

The volume enclosed by the reservoir is substantially empty, except for the ink. For example, there is no absorbent or porous member or materials provided within the reservoir to hold the liquid. Such materials may interfere with the delivery of liquid from the outlet, and may prevent proper emptying of the cartridge.

Such sedimentation can result in the outlet becoming blocked. The shield may thus be configured to prevent sediment entering the outlet.

The opening and the outlet may be vertically misaligned. That is to say, there is no vertical path from a region on a first side of the opening, to the outlet where the outlet is on a second side of the opening. This mitigates against, pigment, precipitates or solid deposits in the ink passing through the opening, and falling due to gravity directly towards the outlet. In turn blocking of the outlet, and pigment, precipitates or solid deposits reaching the outlet is reduced.

According to a yet further aspect of the present disclosure, there is provided a method of manufacturing a product via additive manufacturing, the method comprising: obtaining an electronic file representing a geometry of a product wherein the product is a cartridge according to the first aspect, or any of the above described aspects of a cartridge; and controlling an additive manufacturing apparatus to manufacture, over one or more additive manufacturing steps, the product according to the geometry specified in the electronic file. According to a yet further aspect of the present disclosure, there is provided a kit of parts for assembling a cartridge according to the first aspect, the kit of parts comprising a cartridge and a sediment shield.

Also disclosed herein there is provided a cartridge for storing and dispensing pigmented ink for use with an inkjet printer. The cartridge comprises a reservoir having at least one wall enclosing an internal space for storage of the pigmented ink, an outlet for dispensing the pigmented ink, the outlet provided at a base of the reservoir, and a sediment shield, the sediment shield having an aperture and defining an enclosed fluid communication path between the aperture and the outlet, the aperture being provided at a separation distance from the base of at least 5 millimetres.

It will be appreciated that features described in the context of one aspect may be combined with other aspects described herein. For example, features described above in the context of a cartridge that comprises a sediment shield may also be applied to a sediment shield provided separately from a cartridge, or to a method of manufacture of a sediment shield, or a kit of parts.

Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings in which:

Figure 1 schematically illustrates a continuous inkjet printer;

Figure 2 schematically illustrates a continuous inkjet printer;

Figure 3 schematically illustrates a cross-section of a known ink cartridge;

Figure 4 is a photograph showing an ink cartridge;

Figure 5 schematically illustrates a cross-section of part of a known ink cartridge;

Figure 6 schematically illustrates a cross-section of part of an ink cartridge;

Figure 7 schematically illustrates a sediment shield for use in the ink cartridge of Figure 6;and Figure 8 schematically illustrates a cross section of part of an ink cartridge according to another embodiment of the invention.

In the figures, like parts are denoted by like reference numerals. It will be appreciated that the drawings are for illustration purposes only and may not be drawn to scale.

Figure 1 schematically illustrates an inkjet printer 1. The printer 1 comprises a printer main body 1a connected to printhead 3 by an umbilical cable 1 b. The printer main body 1a may comprise the ink supply system and a printer controller, and the printer main body 1a may have a display 1c and/or keypad 1d for use by an operator. The printhead 3 is arranged to print on a substrate S.

Referring now to figure 2, the inkjet printer 1 comprises an ink supply system 2, the print head 3 and typically a controller 4. The ink supply system 2 may typically comprise an ink system 5 and a service module 6. In figure 2, fluid flow through the inkjet printer 1 is illustrated schematically by solid arrows and control signals are illustrated schematically by dashed arrows. The service module 6 typically comprises two cartridge connections for engagement with a fluid cartridge. In particular, the service module 6 may comprise an ink cartridge connection 7 for engagement with an ink cartridge 8 and a solvent cartridge connection 9 for engagement with a solvent cartridge 10. The service module 6 further comprises a printer connection 11 for releasable engagement with an inkjet printer. The printer connection 11 typically comprises a plurality of fluid ports, each fluid port arranged to connect to a fluid pathway within the inkjet printer 1 to allow fluid to flow between the service module 6 and other parts of the inkjet printer 1 , such as the ink system 5 and the print head 3 (via the umbilical 1 b). The printer connection 11 further comprises an electrical connector arranged to engage with a corresponding connector on the inkjet printer 1 . Each of the ink and solvent cartridge connections 7, 9 typically comprises a fluid connector for engaging an outlet of respective ink and solvent cartridges 8, 10 so as to allow fluid to flow from the cartridges 8, 10 into the service module 6. From the service module 6, ink and solvent can flow to the ink system 5 via the printer connection 11 . In operation, ink from the ink cartridge 8 and solvent from the solvent cartridge 10 can be mixed within the ink system 5 so as to generate printing ink of a desired viscosity which is suitable for use in printing. This ink is supplied to the print head 3 and unused ink is returned from the print head 3 to the ink system 5. When unused ink is returned to the ink system 5 from the print head 3, air may be drawn in with ink from a gutter of the print head 3. The air may then become saturated with solvent in the gutter line.

The ink jet printer 1 is typically controlled by controller 4. Controller 4 receives signals from various sensors within the inkjet printer 1 and is operable to 10 provide appropriate control signals to the ink supply system 2 and the print head 3 to control the flow of ink and solvent through the inkjet printer 1. The controller 4 may be any suitable device known in the art, and typically includes at least a processor and memory.

In operation, ink is delivered under pressure from ink supply system 2 to print head 3 and recycled back via flexible tubes which are bundled together with other fluid tubes and electrical wires (not shown) into the umbilical cable 1 b (shown in figure 1). The ink supply system 2 is typically located in a cabinet or main body 1a and the print head 3 is disposed outside of the cabinet, connected to the cabinet via the umbilical cable 1b. In order to maintain correct consistency of the ink, the ink supply system 2 may be operable to mix ink removed from the cartridge 8 with solvent removed from the cartridge 10 and to mix them together so as to obtain an ink having the correct viscosity and/or density for a particular printing application.

Figure 3 shows a schematic cross-section view of an ink cartridge 8 which could be used within the printer 1 shown in figure 1. The ink cartridge 8 includes a reservoir 12 defining an internal volume 14. The cartridge 10 further comprises an outlet 16 for dispensing the contents of the cartridge 10 to the ink supply system 13 of the printer 1. The outlet 16 may be provided with a fluid-tight seal 17 or valve which forms a fluid-tight engagement with the ink cartridge connection 7 of the ink supply system 2. The reservoir 12 comprises a base wall 18 a top wall 20 and opposing perimeter side walls 22 extending between the base wall 18 and the top wall 20. Opposing face walls 24 (not shown in Fig 3) also extend between the base wall, the top wall 20 and the two opposing side perimeter side walls 22.

The cartridge 1 is made of a non-elastic and flexible material. “Non-elastic” means that the material does not stretch easily under tension by becoming longer/wider and thinner. “Flexible” means that the material is able to bend or to deform easily. It will be understood that the description of the cartridge above refers to the cartridge 8 being in an orientation in which the outlet 16 is provided at the bottom of the cartridge, in the base wall 16. Of course, during storage and transport the cartridge 8 may be orientated in any way. However, in use, it will generally be the case that the cartridge is orientated with the outlet 16 towards (although not necessarily precisely at) the lowest side. In this way the ink will be concentrated at the lower end of the cartridge, with any air gap provided at the upper side of the cartridge 8. Such an arrangement ensures that air is not sucked out of the cartridge 8 via the outlet 16.

In the illustration shown in figure 3, ink 26 is stored within the reservoir 12 and extends from the bottom wall 18 of the reservoir 12 up to a fill line F which is approximately 90% of the way up the perimeter side walls 22. A void 28 is provided at the upper end of the cartridge, adjacent to the top wall 20, accounting for approximately 10 % of the internal volume of the reservoir 12.

There is no venting hole provided in the reservoir 12. That is, the outlet provided the only fluid pathway between the internal volume within the reservoir and the outside. A negative pressure is applied (by a pump provided within the ink supply system 2) to the outlet 16, resulting in ink being removed from the reservoir 12. During use, the pressure within the pressure within the reservoir gradually decreases as more ink is removed, and the absence of any venting hole prevents air (or another gas) from entering the reservoir to equalise the pressure. As a consequence, as liquid is dispensed from the reservoir 12, the reservoir 12 begins to collapse (or deform) in order to accommodate the decreasing internal volume of the reservoir 12. In an example, the overall volume of the reservoir 12 is 770ml, and the filling volume of liquid within the reservoir 12 is around 750ml, leaving a head space of 20ml. A pump providing 400mbar vacuum may be used to withdraw the liquid from the reservoir 12. When substantially all of the liquid has been withdrawn from the reservoir 12, the reservoir 12 becomes substantially fully collapsed and severely deformed, eventually achieving an empty internal space (or void) of around 20ml.

As described above, particles of pigmented ink can settle during storage to form a sediment layer. Such a sediment layer 30 can be seen along the base wall 18 in figure 3. The sediment layer may be the thickness of several millimeters (e.g. 3 mm) in the bottom or sides of the cartridge. The sediment layer may have formed after several days, weeks, or months of storage. For example, a sediment layer may begin to form after around two weeks of storage. It will be understood, of course, that characteristics of the formation of any sediment layer will depend upon the type and concentration of pigment within the ink. For example, pigmented inks containing hard pigment particles (e.g. TiO2) may sediment more quickly than those inks containing softer pigments (e.g. Isoindoline, Quinacridone or Carbon). Typically Hard pigmented inks provide greater contrast as they are opaque and are able to reflect light. Soft pigments do this to a lesser degree.

Figure 4 shows a photograph taken of a cartridge which has been cut in half after it has been substantially emptied. A sediment layer 30 can clearly be seen along the base wall 18 of the cartridge, and around the outlet 16.

Referring again to figures 3 and 4, it can be seen that the sediment layer 30 extends into the region of the cartridge around the outlet 16. An ink needle 32, which forms part of the ink cartridge connection 7 can be seen clearly in Figure 3 extending into the outlet 16.

Figure 5 shows a cross-section of the outlet, showing the construction in more detail. The seal 17 takes the form of a septum, which extending across the outlet 16 preventing ink 26 from leaking from the outlet 16. When installed in a printer, the needle 32 is pushed through the septum 17 allowing ink 26 to be removed from within the cartridge 8. The needle may typically extend into the outlet by up to around 10 millimeters. Of course the length of the needle may vary between different applications, the width of the needle may also vary depending on the ink in use, and the relative rate at which the ink is to be extracted from the cartridge. It will be understood from Figure 5 that it would be relatively easy for the opening of the needle to become blocked by sediment drawn from within the cartridge, or settling within the region of the outlet 16 surrounding the needle 32. In this case, the needle may be prevented from extracting ink from the cartridge. Alternatively, sediment may be drawn into the needle, and may cause blockages in other components of the printer 1 (e.g. filters, valves, pipes, etc.). In such circumstances, operation of the printer may be stopped and cleaning may need to be carried out.

So as to prevent pigment sedimentation from entering the needle 32, a sediment shield is provided according to an aspect of the present disclosure. Figure 6 shows a schematic cross-section view of the outlet region of an ink cartridge 8 which includes a sediment shield 34. In all other respects, the ink cartridge 8 is similar to the cartridge described above with reference to Figure 3. Like components are provided with like references and will not be described again.

As can be seen clearly in Figure 6, the sediment shield is provided around and over the needle 32 and is arranged within the outlet 16. A similar sediment shield can be seen in the photograph of Figure 4. The sediment shield 34 includes a first end 36 which is disposed adjacent to the septum 17 within the outlet 16 and includes an internal fluid pathway 38 which extends from the first end 36 to a second end 40. The second end 40 is provided with a plurality of apertures 42 which connect the internal pathway 38 to the needle 32, which is inserted into the pathway 38 at the first end 36. In this way, the sediment shield 34 defines a closed fluid communication path between the apertures 42 and the needle 32, which provides an outlet for ink from the reservoir 12. The apertures 42 are provided at a distance from the base wall 18 which is sufficient to ensure that, in all ordinary circumstances, the apertures 42 are at a height which is greater than the thickness of any sediment layer 30. The shield 34 is further configured to maintain a separation between the apertures 42 and the perimeter walls 22, and top walls 20, so as to ensure that sediment does not block the apertures even if the cartridge is stored in different orientations. It will further be understood that when the reservoir 12 is full of ink, the shield 34 is configured to maintain a separation (e.g. at least 5 mm) between the apertures 42 and the face walls 24. However, when the cartridge has been emptied of ink, the collapse of face walls 24 may result in the face walls 24 coming close to the apertures 42. In alternative embodiments, the sediment shield 34 may comprise at least one rib or protrusion on the elongate surface, which extend radially outwardly from sediment shield 34. Accordingly, the at least one rib or protrusion can maintain a separation distance between the elongate surface of the sediment shield 34 and a face wall 24 of the cartridge when the reservoir is nearly empty. In doing so, the face walls 24 are prevented from contacting the apertures 42 of the sediment shield 34, and thereby allow ink to leave the reservoir via the aperture 42 even when the cartridge has nearly been emptied of ink. The at least one rib or protrusion can prevent complete collapse of the face walls 24. When the cartridge 8 is in use, the elongate surface of the sediment shield may be a substantially vertical surface and be generally orthogonal to the base 18 of the cartridge 8. Figure 7 shows a schematic illustration of the sediment shield 34 removed from the outlet 16. The sediment shield is substantially as described with reference to Figure 6. The overall length of the sediment shield in this embodiment is approximately 50 millimetres, with a single opening 37 being provided at the first end 36. The shield 34 is substantially cylindrical in shape, having a constant outer diameter of around 7 millimetres. The shield 34 may be formed from a relatively rigid plastic material such as, for example, PPS or PEEK. It will be understood that any suitable material may be used, and that the material (and thickness) may be selected so as to provide a rigid tube which requires considerable force to be bent or significantly deformed. This prevents the shield from collapsing when the cartridge collapses, or from flexing or falling over, such that the apertures 42 fall into regions of sediment.

The outlet opening 37 is configured to receive a needle 32 inserted through the septum 17 into the outlet 16. The inner diameter of the opening 37, and also the fluid pathway 38 is the same at around 4 millimetres. The inner diameter of the opening 37 is greater than the outer diameter of the needle 32, which may be approximately 2.5 millimetres. This allows the ink to flow along the fluid pathway and into openings which may be provided on the sides of the needle 32. Alternative outlet or sealing arrangements may be provided, with adaptations being made to the shield as necessary to allow the shield to engage with the outlet, and to shield the outlet from sediment.

The internal pathway 38 extends from the first end 36 to the second end 40 of the shield 34. As noted above, a plurality of apertures 42 are provided close to the second end 40. The apertures are around 2 millimetres in diameter. In the illustrated embodiment, the apertures 42 are provided around 4 millimetres from the second end 40. In the illustrated embodiment, four apertures 42 are provided which are disposed at approximately 90 degrees from one another around the external circumferential surface of the cylindrical shield 34. The apertures 42 are each in fluid communication with the internal pathway 38. Provided four apertures in this way allows the four apertures to be easily formed by a cross drilling.

The second end 40 of the shield 34 is closed. That is, whereas the first end 36 includes the opening 37 which is disposed along the axial direction of the shield 34, the second end has no such axial aperture such that the top surface of the shield 34 at the second end 40 is closed, and does not provide any pathway for fluid, or indeed sediment, to enter the internal pathway 38. In other words, the closed second end prevents fluid from entering the internal passage 38 in a vertical direction, when the cartridge is installed in a printer. Rather, the only pathway through which fluid can enter the internal passage 38 is via the apertures 42, which are disposed around the vertical surface of the shield 34, rather than the horizontal top surface.

The top horizontal surface can be considered to be barrier which blocks fluid from entering the internal passage 38 via the top horizontal surface of the second end 40. The barrier is integrally formed with the vertical surface of the shield 34. In other embodiments, the barrier may be a cap or cover which is placed over the second end of the shield 34; the cap or cover may be sealed to the sediment shield 34.

It will be understood of course that in alternative embodiments different dimensions and shapes may be used as appropriate. For example, the length, the outer diameter, the internal diameter, and the aperture size and position may be varied, and may be selected so as to allow the shield to fit comfortably within the outlet 16, which, in this instance has an internal diameter of around 10 millimetres. In other embodiments, the sediment shield 34 may comprise a bend. The bend may further restrict any sediment which enters the internal passage 38 from reaching the first end 36. This is because a bend in the sediment shield 34 causes the centroid of the internal passage 38 to deviate from an axial path/line, such that sediment cannot simply fall under gravity towards the outlet 16. Instead any sediment would have to pass along the bend in the internal passage 38. In addition, and advantageously, a bend in the sediment shield may allow for insertion into different shaped cartridges, for example, cartridges which do not have an outlet provided on a planar base. Providing a bend in the sediment shield 34, also allows for a vertically closed top or barrier to be provided even when the outlet of the cartridge is not in vertical or axial alignment with the second end 40 of the sediment shield 34.

The shield 34 may be secured in the outlet 16 be interference fit. For example, the external diameter of the shield 34 may be substantially equal to the internal diameter of the outlet 16, allowing an interference fit to be achieved between the shield and the cartridge. Of course, alternative securing mechanisms may be used as required. Further, in an alternative embodiment, at least a portion of the sediment shield 34 may be flexible; such that the sediment shield can be more easily manipulated into place in the cartridge and/or aid in providing an interference fit at the outlet 16 of the cartridge.

The above described arrangement ensures that during storage, or indeed during use when the ink cartridge 8 maybe installed within a printer 1 for an extended period of time, any sedimentation of pigment within the cartridge 8 does not fall upon, or block, the outlet 16, and in particular the needle 32. The apertures 42 provided around the external circumferential surface of the shield 34 ensure that there is, however, a fluid pathway from the internal volume within the reservoir 12 to the outlet 16, allowing ink to be removed from the cartridge 8.

In this way, correct functioning of the cartridge 8, and printer 1 in which the cartridge is installed maybe prolonged, with disruption due to blocked ink pipes being avoided, or at least reduced.

It will be understood that the internal volume within the cartridge is empty, except for the presence of ink, or air or solvent vapor which may fill a small region of the cartridge which is not filled with ink (i.e. void 28). In particular, there is no substrate, or porous member, within the cartridge which holds the ink.

Furthermore, as described above, as ink is removed from the cartridge 8, the reservoir 12 will gradually collapse. It will be understood, therefore, that as ink is removed from the cartridge 8 the walls of the cartridge, and in particular the opposing face walls 24, will gradually collapse towards one another, reducing the internal volume of the reservoir 12 significantly. Eventually the face walls 24 may come into contact with each other, with a small residual volume of the reservoir 12 being formed around the perimeter walls 22 and top and bottom walls 20, 18. Any ink remaining within the cartridge 8 will be confined to these perimeter regions, and, provided that the cartridge remains in an upright orientation (for example as shown in the Figures), the ink will be concentrated towards the lower part of the cartridge and along the base wall 18.

In view of the collapsing nature of the reservoir 12, it will be understood that if apertures 42 where only provided on surfaces of the shield 34 that were facing the sidewalls 24, they could become blocked by contact with the sidewall 24. However, by providing four apertures disposed at 90 degrees from one another around the external surface of the shield, it is possible to ensure that, regardless of the orientation of the shield 34 relative to the walls, at least one aperture will always be facing away from any of the face walls 24. In this way, it can be ensured that ink will be able to enter the apertures 42 regardless of the extent to which the reservoir 12 has collapsed. This allows the shield 34 to be installed without precise alignment

Of course, alternative numbers of apertures may be used. For example, three apertures, or five apertures may be evenly disposed around the external surface of the shield 34. Further alternatives may also be used. For example, a single aperture may be provided, or a pair of elongate apertures extending around the circumferential of the shield.

The shield 34 is also provided with a plurality of grooves 44 which extend from the first end 36 to the second end 40 along the outer surface of the shield 34. The grooves 44 are substantially parallel to the internal pathway 38 and extend all the way to the apertures 42. Furthermore, the grooves 44 are substantially aligned with the apertures 42 such that each of the four grooves 44 terminates at a respective one of the four apertures 42. The grooves 44 thus provide an additional pathway along the external surface of the shield 34 along which fluid (i.e. ink) can flow from the internal volume within the reservoir 12 and into the apertures 42. This further allows the majority of any ink remaining in the reservoir 12 to be extracted via the internal pathway 38, even when the reservoir is substantially collapsed. That is, even if the face walls 24 are substantially touching, and are pressed against the external surfaces of the shield 34, the grooves 44 will allow any ink pooling towards the base wall 18 to flow up the grooves 44, through the aperture 42, and down the internal pathway 38 so as to be transported through the needle 32 when a negative pressure is applied to the outlet 16. In this way, it is possible to ensure that a maximum amount of ink can be extracted from the cartridge while simultaneously preventing sediment from being drawn into the needle 32. The grooves 44 may have a width of approximately 2 millimetres.

In alternative embodiments, the grooves 44 may not be substantially parallel to the internal pathway 38. For example, the grooves 44 may extend in a spiral around the outer surface of the sediment shield 42 from between the first end 36 and the second end 40. The grooves 44 may extend from the first end 36 to the second end 40 in any suitable manner. In other embodiments, the grooves 44 may extend from the apertures 44 at the second end 40, towards the first end 36, but end at the first end 36 above where a sediment layer would be when installed in a cartridge. For example, the end of the grooves 44 at the first end 36 may be spaced approximately 2 millimetres from the base wall 18 of the cartridge so as to mitigate against any pigment, precipitates or solid deposits in a sediment layer being drawn into the grooves 44.

Of course, the sediment shield may comprise only a single groove 44. The single groove, may extend from the first end 36 (including a region of the first end, spaced above the base wall 18) to the second end 40 substantially parallel with the internal pathway 38, or in a spiral around the outer surface of the sediment shield 42, or in any other suitable shape or manner.

It can be seen that the body of the shield 34 between the first end 36 and the apertures 42 (which are disposed towards the second end 40) is substantially free from apertures. That is, the opening 37 at the first end 36 and the apertures 42 at the second end, are the only openings into the shield 34. The region between those apertures maybe referred to as a closed region which encloses the fluid communication path between the aperture(s) and the outlet.

The closed region may extend for a certain minimum distance above the level of the base wall 18. The level of the base wall 18 may be considered to be defined by a plane 18P substantially coincident with an internal surface of the base wall 18 around the outlet 16. As shown in Figure 6, the distance between the internal surface of the base wall 18 and the apertures 42 is defined by distance D. In the embodiment shown, and in particular in the arrangement shown in Figure 6, the distance D is preferably at least 5 millimetres above the level of the base wall 18, this ensures that even while significant sedimentation has occurred, the apertures 42 are above the level of sedimentation. It will of course be understood that the extent to which these apertures are provided above the base wall will vary upon particular circumstances, and the level of sedimentation expected. However, a 5-10 millimetre closed region above the base wall is considered to provide a reasonable degree of protection form sediment uptake, while also ensuring as much ink can be removed from the cartridge as possible (since the further the apertures 42 are from the base wall 18, the more ink will remain in the cartridge when it is effectively “empty”). The overall length of the shield tube 34 will vary depending upon the design of the outlet 16. Indeed, in the illustrated embodiment the outlet extends for a distance d1 of around 25 millimetres from the base wall. That is, the septum 17 is around 25 millimetres below the level of the base wall 18. In one or more embodiments (such as that which is illustrated), the shield has a length of at least 25 millimetres from the septum 17 to become level with the base wall 18, and therefore may extend a further distance above the level of the base wall before the apertures are provided. In the illustrated arrangement it will be appreciated that a shield length of at least 35 millimetres should be provided so as to provide a sufficient separation (i.e. around 5 millimetres), between the level of the base wall 18, and the apertures 42. A further distance d2 is provided above the apertures, before the top surface of the shield 34. In alternative arrangements a different shield length maybe appropriate.

It will further be understood that additional apertures can be provided within the shield at a level above this minimum level. That is, additional rows of apertures maybe provided at within the region d2, at distances which are further away from the base wall 18 than the minimum level of around 5 millimetres. However, it is important that no apertures are provided in the closed region of the shield 34, which would allow extremely thick viscous ink to be drawn into the outlet.

It will be appreciated that in the above described embodiment a needle 32 is used to extract ink from the reservoir 12 via a septum 17 provided at the outlet 16. However, in alternative arrangements other fluid seals or valve arrangements may be used, and may still benefit from operation of the shield (which will prevent sediment from entering the outlet.

Similarly, while the sediment shield may be particularly beneficial when used with collapsing cartridges (i.e. those with no air or pressure release vents), it can still be used to beneficial effect in systems having a pressure equalisation system of this sort (or indeed any other sort). Such a shield may omit certain features described herein (e.g. grooves 44, and/or a plurality of apertures 44 disposed around the outer circumference of the shield 34, with a single aperture being sufficient). This is because, with a noncollapsing reservoir, the risk of the apertures becoming blocked by a collapsing surface wall is much reduced. The cartridge 8 may be formed from a thermoplastic material, suitably by rotational moulding or blow moulding. The thermoplastic material may, for example, be high density polyethylene (HDPE). HDPE provides a high strength-to-density ratio and is resistant to many different solvents. It will be appreciated that by rotational moulding or blow moulding, the body of the cartridge 8 including the reservoir 12 and the outlet 16 can be formed at the same time as a single-piece item.

The shield may be formed from a thermoplastic material. The thermoplastic material may, for example, be polypropylene (PP). The shield may be formed from any suitable process. For example, the shield may be formed by injection molding. Injection molding provides a low cost manufacturing process suitable for high volume production.

The shield may be formed using an additive manufacturing process. Similarly, the cartridge could be formed using an additive manufacturing process. The present disclosure therefore also includes methods of manufacturing the shield and/or the cartridge via additive manufacturing and computer software, firmware or hardware for controlling the manufacture of such products via additive manufacturing. As used herein, “additive manufacturing” refers generally to manufacturing processes wherein successive layers of material(s) are provided on each other to “build-up” layer-by-layer or “additively fabricate”, a three-dimensional component. A common example of additive manufacturing is 3D printing; however, other methods of additive manufacturing are available. Rapid prototyping or rapid manufacturing are also terms which may be used to describe additive manufacturing processes. Additive manufacturing processes typically fabricate components based on three-dimensional (3D) information, for example a three-dimensional computer model (or design file), of the component. A design file, or computer aided design (CAD) file, is a configuration file that encodes one or more of the surface or volumetric configuration of the shape of the product, and can take any now known or later developed file format.

The structure of one or more parts of the shield and/or cartridge described herein may be represented digitally in the form of a design file, and the design file may be produced using modelling (e.g. CAD modelling) software and/or through scanning the surface of a physical sediment shield and/or cartridge (e.g., a sediment shield prototype, and/or cartridge prototype) to measure the surface configuration of the sediment shield and/or cartridge. Once obtained, the design file may be converted into a set of computer executable instructions that, once executed by a processer, cause the processor to control an additive manufacturing apparatus to produce a shield and/or cartridge according to the geometrical arrangement specified in the design file. The conversion may convert the design file into slices or layers that are to be formed sequentially by the additive manufacturing apparatus. The instructions (otherwise known as geometric code or “G-code”) may be calibrated to the specific additive manufacturing apparatus and may specify the precise location and amount of material that is to be formed at each stage in the manufacturing process. Design files or computer executable instructions may be stored in a transitory or non-transitory computer readable storage medium. The code or instructions may be translated between different formats, converted into a set of data signals and transmitted, received as a set of data signals and converted to code, stored, etc., as necessary. The instructions may be an input to the additive manufacturing system, which may execute the instructions to fabricate the shield described herein.

Once each of the shield 34 and cartridge 8 have been manufactured (by whatever means), and the cartridge has been filled with ink, the shield 34 may be inserted into the outlet 16 of the cartridge 8, forming an interference fit. In this way, the sediment shield and cartridge can be arranged such that the outlet opening 37 of the sediment shield 34 is engaged with the outlet 16 of the cartridge so as to define a enclosed fluid communication path between the apertures 42 and the outlet 16.

Once the shield has been inserted, the septum 17 can be applied (and possibly retained by a crimped retaining ring - not shown). It will be appreciated that while the cartridge can be filled after the insertion of the shield but before the application of the septum 17, this may reduce the filling speed significantly.

As described above, the provision of several apertures 42 disposed around the outer surface of the shield 34 ensures that the cartridge assembly process does not need to take into account shield orientation with respect to the outlet 16. Of course, it will be appreciated that the shield should be inserted into the outlet 16 with the second end 40 inserted first, such that the first end 36 is provided around the needle 32 when a needle is subsequently inserted through the septum 17.

Figure 8 shows a schematic cross-section view of an ink cartridge 108 comprising a sediment shield 134 according to another embodiment of the invention. The ink cartridge 108 includes a reservoir 112 defining an internal volume 114. The cartridge 108 further comprises an outlet 116 for dispensing the contents of the cartridge 108 to an ink supply system of a printer. The reservoir 112 comprises a base wall 118 a top wall 120 and opposing perimeter side walls 122 extending between the base wall 118 and the top wall 120. Opposing face walls (not shown in Fig 8) also extend between the base wall, the top wall 120 and the two opposing side perimeter side walls 122.

It will be understood that the description of the cartridge 108 above refers to the cartridge 108 being in an orientation in which the outlet 116 is provided at the bottom of the cartridge, in the base wall 118. Of course, during storage and transport the cartridge 108 may be orientated in any way. However, in use, it will generally be the case that the cartridge 108 is orientated with the outlet 116 towards (although not necessarily precisely at) the lowest side. In this way the ink will be concentrated at the lower end of the cartridge, with any air gap provided at the upper side of the cartridge 108. Such an arrangement ensures that air is not sucked out of the cartridge 108 via the outlet 116.

There is no venting hole provided in the reservoir 112. That is, the outlet 116 provided the only fluid pathway between the internal volume 114 within the reservoir and the outside.

A negative pressure is applied (by a pump) to the outlet 116, resulting in ink being removed from the reservoir 112. During use, the pressure within the reservoir 112 gradually decreases as more ink is removed, and the absence of any venting hole prevents air (or another gas) from entering the reservoir 112 to equalise the pressure. As a consequence, as liquid is dispensed from the reservoir 112, the reservoir 112 begins to collapse (or deform) in order to accommodate the decreasing internal volume of the reservoir 112. In an example, the overall volume of the reservoir 112 is 770ml, and the filling volume of liquid within the reservoir 12 is around 750ml, leaving a head space of 20ml. A pump providing 400mbar vacuum may be used to withdraw the liquid from the reservoir 112. When substantially all of the liquid has been withdrawn from the reservoir 112, the reservoir 112 becomes substantially fully collapsed and severely deformed, eventually achieving an empty internal space (or void) of around 20ml.

Although not shown, the outlet may be configured to receive a needle, to enable the ink to be withdrawn from the reservoir 112. The sediment shield 134 is provided in the reservoir 112. The sediment shield 134 is a substantially flat structure, for example a plate, and extends between the opposing face walls and between the side walls 22. The sediment shield 134 divides the reservoir 114 into a first region 114a, above the sediment shield 134, and a second region 114b below the sediment shield 134. The sediment shield 134 comprises an aperture 144. The aperture 144 is a hole or opening in the sediment shield 134 and there is an enclosed fluid communication path from the aperture 144 to the outlet 116. There is a fluid pathway from the first region 114a to the outlet 116 of the cartridge 108, via the aperture 144. Fluid in the first region 114a may only exit the cartridge via the outlet 116, and passes through the aperture 144 to do so.

The aperture 144 may have a substantially circular cross-section. The aperture 144 may have a diameter that is greater than or equal to around 0.5 millimetres. The aperture 144 may have a diameter that is less than or equal to around 4 millimetres. The aperture 144 may have a diameter that is around 2 millimetres.

The sediment shield 134 may be made of a material that provides a sufficient rigidity, such that the sediment shield 134 can maintain its shape without relying upon, for example, any floating force exerted by the ink. The sediment shield 134 may be a moulded member. The sediment shield 134 may be integrally formed with the walls of the cartridge 108. The sediment shield 134 may be a separate member which is inserted into the reservoir 122 during a manufacturing or assembly process; the sediment shield may form an interference fit with walls of the reservoir 112.

The shield 134 is further configured to maintain a separation between the aperture 144 and the perimeter walls 122, and top walls 120, so as to ensure that sediment does not block the apertures even if the cartridge is stored in different orientations. It will further be understood that when the reservoir 112 is full of ink, the shield 134 is configured to maintain a separation (e.g. at least 5 mm) between the aperture 144 and the side walls 122. In use, as ink is withdrawn from the cartridge, the sediment shield 134 maintains a separation distance between the aperture 144 and any wall of the reservoir 122. The separation distance that is maintained may be at least 5 millimetres. The sediment shield 134, and the aperture 144, may be provided at a separation distance from the base 118 of at least 5 millimetres. As already described above, ink may comprise precipitates and solid deposits, and where ink is pigmented ink, the ink comprises pigments. Said precipitates, pigments, and solid deposits, can settle on surfaces of the cartridge 108, if the cartridge 108 is stored for long periods of time, and form a sediment layer. The sediment layer, if settling on the base 118 of the cartridge can block the outlet 116 of the cartridge 108 and prevent complete emptying of the cartridge. In addition, if sediment is able to exit the cartridge 108 it can cause blockages in the printer system that the ink cartridge 108 is connected with.

In Figure 8, a sediment layer may form on the base wall 118 of the cartridge 108 and on an upper surface 138 of the sediment shield 134. Because the sediment shield 134 is provided towards the base wall 118 of the cartridge 108, the first region 114a has a larger volume for storing ink compared to the second, lower, region 114b. As such, if the cartridge it left for an extended period of time, the sediment layer that will form on the upper surface 138 of the sediment shield 134 will be greater (i.e. thicker) than the sediment layer that forms on the base wall 118, due to proportionally more pigment, precipitates, and solid deposits being in the upper region 114a. The sediment shield 134 therefore restricts sediment from reaching the outlet 116 of the cartridge.

When the cartridge 108 is full of ink, the volume defined by the first region 114a may be around 99% of the total volume of the reservoir 112, and hence the volume of the reservoir 112 defined by the second region is around 1%. The volume of the reservoir 112, when full of ink (i.e. when the reservoir is filled to a predetermined fill volume, which may be indicated by a fill line), defined by the first region 114a may be between around 90% and 99%. The volume of the reservoir 112, when full of ink, defined by the second region 114b may be between around 1 % and 10%.

The volume of the first region 114a may be between around 1 .5 to around 10 times larger than the volume of the second region 114b, when the ink cartridge is full of ink (i.e. when the reservoir is filled to a predetermined fill volume, which may be indicated by a fill line). The volume of the first region 114a may be between around 5 to around 8 times larger that the volume of the second region 114b when the ink cartridge is full of ink. The volume of the first region 114a may be between around 7 times larger that the volume of the second region 114b when the ink cartridge is full of ink. It will be appreciated, that the volume of the lowermost region 114b the reservoir 112 should be smaller, and preferably as small as possible in view of other constraints of the cartridge, (which may include but are not limited to the shape of the cartridge, and the size of a needle which is to be inserted into the cartridge), in order to minimise the thickness of a sediment layer which may form on the base wall 118 of the cartridge 108.

The aperture 144 is not aligned with the outlet 116. In other words, the aperture 144 is not vertically above the outlet 116. This is because, if the aperture 144 were aligned with the outlet 116, any sediment which passes through the aperture 144, would then fall, due to gravity, directly towards the outlet 116, and potentially block the outlet 116. By the aperture 144 being vertically misaligned with the outlet 116, any sediment that passes through the aperture 144, is more likely to settle on the base wall 118 of the cartridge rather than at the outlet 116. Therefore, the sediment shield 134 blocks a direct vertical path between ink in the first region 114a and the outlet 116 of the ink cartridge 118.

In Figure 8, the aperture 144 is spaced apart from the side wall 122. In other embodiments, the aperture 144 may be located at an edge of the sediment shield 134, such that there is a small region, at the edge of the sediment shield 134 which does not contact a side wall 122 or an opposing wall, where the aperture 144 is provided. In this instance, the aperture 144 may include a notch or recess in the sediment shield 144. Alternatively, the sediment shield 134 may extend between opposing walls, and extend from one of the side walls 122 towards the opposing side wall 122, but only be in contact with one of the side walls 122. In this case, the aperture 144 would be an elongate aperture 144 defined by the sediment shield 134 and a side wall 122.

The aperture 144 is an opening in the sediment shield 134. In other embodiments, a mesh or a filter may extend across the aperture 144. The mesh or filter would allow the passage of ink between the first region 114a and the second region 114b, but would comprise pores which are sized to prevent the passage of pigment, precipitates and solid deposits between the first region 114a and the second region 114b. Further, the sediment shield 134 may comprise at least two apertures 144. For the reasons described above, it is preferable that any apertures 144 provided in the sediment shield are not in vertical alignment with the outlet 116 (i.e. the apertures 144 and the outlet are vertically misaligned). The sediment shield 134 is shown in Figure 8 as extending between the side walls 22 and the opposing walls in a plane that is parallel with the base wall 118. In other embodiments, the sediment shield 134 may be a sloped wall or plate relative to the base wall 118, and is configured to direct sediment away from the aperture 144. The sediment shield 134 may, in other embodiments, be a dome shaped member, such that it comprises a convex surface and a concave surface. Where the convex surface defines at least part of the second region 114b and the concave surface defines at least part of the first region 114a (i.e. the concave surface defines the upper surface 138 of the sediment shield).

Although the sediment shield 134 of Figure 8 is shown in isolation of the sediment shield 34 described in Figures 6 and 7, it will be appreciated that the sediment shield 34, and variants of it, can be used in an ink cartridge, in combination with the sediment shield 134 of Figure 8, and variants of it. Providing the sediment shield 34, as shown in Figure 6 and 7, would prevent sediment formed in a sediment layer on the base wall 118 from reaching the outlet 116; and the sediment shield 134, provided above, would reduce the thickness of the sediment layer formed at the base wall 118, thereby further mitigating against sediment blocking the outlet. It will be appreciated, that if a sediment shield 34 of the type shown in Figures 6 and 7 is provided in combination with a sediment shield 134 of the type shown in Figure 8, the lowermost region 114b of the reservoir should define a height which is large enough to receive the sediment shield 34.

While embodiments of the present disclosure are described above, it will be appreciated that these are provided by way of example only, and are not intended to be limiting in nature. Indeed, various alternatives and variations to the specific embodiments described herein will be understood to be possible without departing from the scope of the present disclosure. The scope of the invention is defined by the appended claims.

In addition to or as an alternative to the above, the following examples are described. The features described in any of the following examples may be utilized with any of the other examples described herein.

Example 1 A cartridge for storing and dispensing pigmented ink for use with an inkjet printer, the cartridge comprising: a reservoir having at least one wall enclosing an internal space for storage of the pigmented ink, an outlet for dispensing the pigmented ink, the outlet provided at a base of the reservoir; and a sediment shield, the sediment shield having an aperture and defining an enclosed fluid communication path between the aperture and the outlet, the aperture being provided at a separation distance from the base of at least 5 millimetres.

Example 2

A cartridge for storing and dispensing ink for use with an inkjet printer, the cartridge comprising: a reservoir having at least one wall enclosing an internal space for storage of the ink, an outlet for dispensing the ink, the outlet provided at a base of the reservoir; and_a sediment shield, the sediment shield having an aperture and defining an enclosed fluid communication path between the aperture and the outlet, the aperture being provided at a separation distance from the base of at least 5 millimetres.

Example 3

A cartridge according to example 1 , wherein the sediment shield is configured to restrict a sediment layer, which comprises pigments within the ink and settles on an internal surface of the base, from reaching the outlet.

Example 4

A cartridge according to any combinations of examples 1 to 3, wherein the sediment shield is configured to restrict a sediment layer, which comprises precipitates within the ink and settles on an internal surface of the base, from reaching the outlet.

Example 5

A cartridge according to any combinations of examples 1 to 4, wherein the sediment shield comprises one or more apertures, each of the one or more apertures being provided at a separation distance from the base of at least 5 millimetres; and wherein ink can only pass from the reservoir to the outlet via the one or more apertures. Example 6

A cartridge according to any combinations of examples 1 to 5, wherein the sediment shield comprises a barrier, and the barrier blocks a vertical fluid path between the outlet and the reservoir when the cartridge is installed in a printer, and/or wherein the, or each aperture is provided on an elongate surface of the sediment shield.

Example 7

A cartridge according to any combinations of examples 1 to 6, wherein the sediment shield is configured to maintain the separation distance between the aperture and the base as the ink is dispensed from the outlet.

Example 8

A cartridge according to any combinations of examples 1 to 7, wherein sediment shield is configured to maintain a separation distance of at least 5 mm between the aperture and any wall of the reservoir, when the reservoir is full of ink.

Example 9

A cartridge according to any combinations of examples 1 to 8, wherein the cartridge defines a height from the base when the reservoir is full of ink, and the sediment shield extends from the base less than 50% the height of the cartridge

Example 10

A cartridge according to any combinations of examples 1 to 9, wherein the outlet extends beyond the base.

Example 11 A cartridge according to any combinations of examples 1 to 10, wherein the sediment shield comprises a tube which comprises the, or each, aperture and defines the enclosed fluid communication path between the aperture and the outlet.

Example 12

A cartridge according to example 11 , wherein the tube is rigid.

Example 13

A cartridge according to any combinations of examples 11 to 12, wherein the tube comprises a bend.

Example 14

A cartridge according to any combinations of examples 11 to 13, wherein at least a portion of the tube is flexible.

Example 15

A cartridge according to any combinations of examples 1 to 14, wherein the, or each, aperture is provided at a distance of at least 5 millimetres from a plane of the base at the location of the outlet.

Example 16

A cartridge according to any combinations of examples 1 to 15, wherein the shield comprises a central bore extending from the aperture to the outlet.

Example 17

A cartridge according to any combinations of examples 1 to 16, wherein the shield comprises an outlet opening configured to engage with the outlet.

Example 18 A cartridge according to any combinations of examples 1 to 17, wherein the shield comprises a plurality of apertures, each of the plurality of apertures being separated from the base at a separation distance of at least 5 millimetres.

Example 19

A cartridge according to example 18, wherein the plurality of apertures are disposed around an outer surface of the shield.

Example 20

A cartridge according to any combinations of examples 18 to 19, wherein the shield comprises four apertures disposed at 90 degrees from one another the outer surface of the shield.

Example 21

A cartridge according to any combinations of examples 1 to 20, wherein the shield comprises at least one groove extending along an outer surface of the shield from the base to the aperture.

Example 22

A cartridge according to any combinations of examples 1 to 21 , wherein the shield comprises a plurality of apertures, and a corresponding plurality of grooves, each one of the plurality of grooves extended from the base to a respective one of the plurality of apertures.

Example 23

A cartridge according to any combinations of examples 1 to 22, wherein the separation distance between the aperture and the base is equal to or less than 25 millimetres.

Example 24 A cartridge according to any combinations of examples 1 to 23, wherein the, or each, aperture has a diameter equal to or greater than around 0.5 millimetres; and/or wherein the, or each, aperture has a diameter less than or equal to around 4 millimetres; and/or wherein the, or each, aperture has a diameter around 2 millimetres.

Example 25

A cartridge according to any combinations of examples 1 to 24, wherein the reservoir is a collapsible reservoir.

Example 26

A cartridge according to any combinations of examples 1 to 25, wherein the cartridge is adapted to prevent air from entering the internal space from outside of the cartridge as the liquid is dispensed from the outlet.

Example 27

A cartridge according to any combinations of examples 1 to 26, wherein the reservoir comprises a single fluid port.

Example 28

An inkjet printer comprising: a cartridge according to any combinations of examples 1 to 27; and a fluid connector for engaging with the outlet of the cartridge configured to receive ink from the cartridge.

Example 29

A method of manufacturing a cartridge according to any combinations of examples 1 to 28, the method comprising: providing said reservoir having at least one wall enclosing an internal space for storage of the ink, and said outlet for dispensing the ink, the outlet being provided at a base of the reservoir; providing a sediment shield, the sediment shield having said aperture and an outlet opening for engagement with the outlet of the cartridge, the sediment shield defining an enclosed fluid communication path between the aperture and the outlet opening; and assembling the cartridge by arranging the sediment shield and the cartridge such that the outlet opening of the sediment shield is engaged with the outlet of the cartridge so as to define said enclosed fluid communication path between the aperture and the outlet.

Example 30

A method of manufacturing a cartridge according to example 30, wherein the ink is pigmented ink.

Example 31

A method for storing and dispensing ink from a cartridge for use with an inkjet printer, the method comprising: storing the ink in a reservoir of the cartridge; and dispensing the ink from an outlet of the cartridge; wherein dispensing the ink from the outlet of the cartridge comprises: withdrawing a volume of ink from the reservoir through an aperture, wherein when the cartridge is installed in an inkjet printer, the aperture is provided above a layer of sediment in the ink; and dispensing the volume of ink through the outlet of the cartridge.

Example 32

A method for storing and dispensing ink from a cartridge for use with an inkjet printer, the method comprising: storing the ink in a reservoir of the cartridge; and dispensing the ink from an outlet of the cartridge; wherein dispensing the ink from the outlet of the cartridge comprises: withdrawing a volume of ink from the reservoir through an aperture provided at a separation distance of at least 5 millimetres from a base of the cartridge; and dispensing the volume of ink through the outlet of the cartridge.

Example 33

A method according to any combinations of examples 31 to 32, wherein the volume of ink withdrawn from the reservoir passes through an enclosed fluid communication path between the aperture and the outlet. Example 34

A method according to any combinations of examples 31 to 33, wherein withdrawing the volume of ink through the aperture substantially prevents precipitates in the reservoir from reaching the outlet of the cartridge

Example 35

A method according to any combinations of examples 31 to 34, further comprising maintaining, during withdrawing a volume of the ink from the reservoir, a separation distance between the aperture and any wall of the reservoir.

Example 36

A method according to any combinations of examples 31 to 36, wherein the volume of ink is withdrawn from the reservoir through a plurality of apertures.

Example 37

A method according to any combinations of examples 31 to 35, wherein dispensing ink from the reservoir includes collapsing the reservoir.

Example 38

A cartridge for storing and dispensing ink for use with an inkjet printer, the cartridge comprising: a reservoir having at least one wall defining a volume for storage of the ink, an outlet for dispensing the ink, the outlet provided at a base of the reservoir; and a sediment shield, the sediment shield having an opening and defining an enclosed fluid communication path between the opening and the outlet, the opening being provided above a layer of sediment in the ink.

Example 39 A cartridge according to example 38, wherein the opening and the outlet are vertically misaligned

Example 40

A sediment shield for installation in a cartridge for storing and dispensing ink for use with an inkjet printer, the cartridge comprising a reservoir having at least one wall enclosing an internal space for storage of the ink, and an outlet for dispensing the ink, the outlet being provided at a base of the reservoir, wherein: the sediment shield has an aperture and an outlet opening for engagement with the outlet of the cartridge, the sediment shield defining an enclosed fluid communication path between the aperture and the outlet opening; and the sediment shield is configured such that, when engaged with the outlet of the cartridge, an enclosed fluid communication path is provided between the aperture and the outlet, and the aperture is provided at a separation distance from the base of at least 5 millimetres.

Example 41

A sediment shield according to example 40, wherein the ink is pigmented ink.

Example 42

A computer program comprising computer executable instructions that, when executed by a processor, cause the processor to control an additive manufacturing apparatus to manufacture a sediment shield according any combinations of examples 40 to 41.

Example 43

A cartridge for storing and dispensing ink for use with an inkjet printer, the cartridge comprising: a reservoir having at least one wall enclosing an internal space for storage of the ink, an outlet for dispensing the ink, the outlet provided at a base of the reservoir; and a sediment shield, the sediment shield having an aperture and defining an enclosed fluid communication path between the aperture and the outlet.

Example 44 A cartridge according to example 44, wherein the aperture is provided at a separation distance from the base of at least 5 millimetres.

Example 45

A cartridge according to any combinations of examples 43 to 44, wherein the sediment shield is a plate.

Example 46

A cartridge according to any combinations of examples 43 to 45, wherein the sediment shield comprises a barrier, and the barrier blocks a vertical path between the outlet and a region of the reservoir when the cartridge is installed in a printer.

Example 47

A cartridge according to any combinations of examples 43 to 46, wherein the sediment shield is configured to maintain the separation distance between the aperture and the base as the ink is dispensed from the outlet.

Example 48

A cartridge according to any combinations of examples 43 to 47, wherein the sediment shield extends between at least two opposing walls of the reservoir.

Example 49

A cartridge according to any combinations of examples 43 to 48, wherein sediment shield is configured to maintain a separation distance of at least 5 millimetres between the aperture and any wall of the reservoir, when the reservoir is full of ink.

Example 50 A cartridge according to any combinations of examples 43 to 49, wherein the sediment shield divides the reservoir into a first region and a second region, wherein the first region is vertically above the second region, when the cartridge is installed in a printer.

Example 51

A cartridge according to example 50, wherein the volume of the first region is greater than the volume of the second region.

Example 52

A cartridge according to any combinations of examples 50 to 51 , wherein the sediment shield comprises a convex surface and a concave surface, and the first region is at least partly defined by the concave surface.

Example 53

A cartridge according to any combinations of examples 43 to 52, wherein the aperture and the outlet are vertically misaligned.

Example 54

A cartridge according to any combinations of examples 43 to 53, wherein the sediment shield is substantially parallel with the base of the cartridge.

Example 55

A cartridge according to any combinations of examples 43 to 53, wherein the sediment shield is at an angle relative to the base of the cartridge, and is configured to direct any precipitates in the ink away from the aperture.

Moreover, any of the specific features set forth in any of the examples described above may be combined into beneficial examples of the described embodiments. That is, any of the specific features are generally applicable to all examples of the invention. Various embodiments have been described.