CN108698756B

CN108698756B - Soaking bag

Info

Publication number: CN108698756B
Application number: CN201780010813.0A
Authority: CN
Inventors: F·贝尼纳蒂
Original assignee: Unilever Nederland BV
Current assignee: Ekatra Research And Development Uk Ltd
Priority date: 2016-02-11
Filing date: 2017-02-07
Publication date: 2020-01-10
Anticipated expiration: 2037-02-07
Also published as: CN108698756A; EP3414188A1; WO2017137399A1; PL3414188T3; JP2019504803A; AU2017217607A1; EA037708B1; US20200216258A1; AU2017217607B2; EA201891424A1; BR112018015073A2; EA037708B9; EP3414188B1

Abstract

The invention relates to an inflatable infusion bag (1, 5), wherein the infusion bag is in a permanently compressed state in the absence of water and is transformed into an inflated state in the presence of water.

Description

Soaking bag

Technical Field

The invention relates to a soaking bag. More particularly, the present invention relates to an infusion bag (e.g., tea bag) that expands to adopt a three-dimensional shape when submerged in water.

Background

For many years infusion packets (e.g. tea bags) have typically been flat and are obtained primarily as square or round sheets of porous filter material with infusible material (e.g. tea leaves) sandwiched between the sheets. Such a bag limits the movement of the infusible material within the infusion bag to substantially two dimensions. As a result, the soaking performance of such a pack is limited.

Recently, mass-produced infusion packets having a more three-dimensional state have been developed. Particularly successful are tetrahedral-shaped packets, such as those whose production is described in WO 95/01907 (Unilever). This type of infusion bag is believed to improve infusion performance by allowing more space for the infusible material to move.

Multiple infusion packets are often packaged together in cartons for sale. For example, PG Tips pyramid tea bags are sold in cartons containing 20, 40, 80, 160 or 240 tea bags. A disadvantage of providing three-dimensional infusion packets is that they have a larger volume than two-dimensional packets and therefore cannot be packaged for sale efficiently.

Efforts have been made to provide three-dimensional infusion packets having a flattened configuration for packaging.

EP 0053204 (Unilever) discloses a tea bag having a generally tetrahedral shape having at least one fold allowing it to be folded into a flat configuration. A pulling device secured to the bag facilitates unfolding of the bag.

WO 2013/174710(Unilever) discloses an infusion bag comprising gussets which are substantially flat prior to use and which may rise when submerged in an infusion liquid, such that the infusion bag adopts a more three-dimensional shape.

EP 0846632 (Fuso Sangyo Kabushiki Kaisha) discloses a liquid permeable flexible bag which is folded so that it can be easily contained in an outer package and unfolded upon extraction so that the inner space of the bag is enlarged.

The flattened (or unexpanded) form of such infusion packets is achieved by folding the three-dimensional infusion packet in a defined manner. The three-dimensional shape that the infusion bag is expected to adopt in use will inevitably affect the shape of its flattened form. Furthermore, in order to facilitate mass production of such infusion packets, the flattened form must be achieved by a relatively simple folding pattern. Thus, the expandable infusion packets described in the prior art have only a very limited number of possible configurations in their unexpanded form.

Thus, there remains scope to provide a dip bag form that provides the soaking properties associated with three-dimensional bags and that can be packaged for sale in a more convenient and/or efficient manner than is currently the case.

Disclosure of Invention

In a first aspect, the present invention relates to an inflatable infusion bag, wherein the infusion bag is in a permanently compressed state in the absence of water and is transformed into an inflated state in the presence of water.

The compressive nature of such infusion packets means that they can be conveniently and efficiently packaged. This is advantageous from an environmental point of view, since less secondary packaging material is required to package a given number of infusion packets (e.g. compared to a standard infusion packet having substantially the same inflated state).

In a second aspect, the present invention relates to a package comprising a plurality of inflatable infusion packets according to the first aspect of the present invention.

In a third aspect, the present invention relates to a method of manufacturing an inflatable infusion packet according to the first aspect of the invention.

In a fourth aspect, the present invention relates to an inflatable infusion packet according to the first aspect of the invention obtainable by the method of the third aspect of the invention.

The present invention relates to an inflatable infusion bag, wherein the infusion bag is in a permanently compressed state in the absence of water and is transformed into an inflated state in the presence of water.

As used herein, the term "permanently compressed state" means a form intended to remain stable for an indefinite period of time. The infusion bag itself is in the form of a permanent compression and does not transform into an expanded state in the absence of water. In other words, the infusion packets of the present invention do not rely on an envelope or similar secondary packaging to maintain their compressed form.

When the infusion bag of the present invention is in its permanently compressed state, it cannot be unfolded by merely lightly pulling or manipulating its constituent materials. This is in contrast to infusion packets which have been folded to achieve a flattened form, which, even in the absence of water, tend to adopt a more expanded form when handled in this manner.

The infusion bag of the present invention is transformed into an expanded state in the presence of water. Although (all other parameters being equal) the time it takes for the infusion bag to adopt the expanded state is generally faster in hot water than in cold water, both hot and cold water cause this transition. Therefore, the inflatable infusion bag is suitable for preparing hot and cold beverages.

When the infusion bag of the present invention is in its permanently compressed state, it does not deform during operation and preferably has a substantially rigid structure. When the infusion bag adopts its expanded state in the presence of water, it becomes deformable and preferably has a flexible structure (in other words, they lose the rigidity which they preferably have in the permanently compressed state).

The time taken for the infusion packet to pass from the compressed state to the expanded state in the presence of hot water (for example at a temperature of 90 to 100 ℃) is generally relatively fast and is generally a few seconds. Thus, the expandable infusion packet is particularly suitable for infusion beverages prepared with hot water, such as tea or herbal infusions. Consumers want to prepare such beverages as quickly and conveniently as possible, and the total brewing time is usually not more than 6 minutes. Thus, in the presence of hot water, the infusion bag preferably transitions from the compressed state to the expanded state in no more than 30 seconds, more preferably no more than 20 seconds, and most preferably no more than 10 seconds.

The inflatable infusion packets are also suitable for infusion beverages prepared with cold water (e.g. from

Iced tea brewed in a cold brew tea bag). Such beverages typically have a longer brew time than hot drinks, which may be, for example, 5 minutes or more. Thus, the rapid transition of the infusion packet from the compressed state to the expanded state is less important in view of the consumer acceptance of the product. In the presence of cold water (e.g., at a temperature of 15 to 25 ℃), the infusion bag preferably transitions from the compressed state to the expanded state in no more than 240 seconds, more preferably no more than 180 seconds, still more preferably no more than 120 seconds, and most preferably no more than 90 seconds.

The transition of the inflatable infusion bag from the permanently compressed state to the inflated state results in a "tumbling" motion. Without wishing to be bound by theory, the inventors believe that this movement improves the infusion performance of the infusion bag.

The inflatable infusion packet preferably contains a beverage precursor. As used herein, the term "beverage precursor" refers to a manufacturing composition suitable for preparing a beverage. The beverage precursor can be contacted with an aqueous liquid (e.g., water) to provide a beverage (i.e., a substantially aqueous drinkable composition suitable for human consumption). This process is called brewing. During brewing, the beverage precursor typically releases certain soluble substances into the aqueous liquid, such as flavor and/or aroma molecules.

The beverage precursor preferably comprises plant material, with tea and/or herbal material being particularly preferred. As used herein, "tea plant material" refers to dried leaf and/or stem material (i.e., "leaf tea") derived from tea tree (Camellia sinensis). The term "herbal material" refers to materials commonly used as herbal infusion precursors. Preferably, the herbal material is selected from the group consisting of chamomile, cinnamon, elderberry, ginger, hibiscus, jasmine, lavender, lemongrass, mint, lewis bauhinia, rose hip, vanilla and verbena. The beverage precursor may additionally or alternatively include fruit pieces (e.g., apples, blackcurrants, mangoes, peaches, pineapples, raspberries, strawberries, etc.) and/or other flavor ingredients (e.g., bergamots, citrus peels, synthetic flavor particles, etc.). The beverage precursor preferably excludes plant material that requires pressure for optimal brewing. In particular, the beverage precursor preferably excludes plant material derived from coffee (especially ground coffee).

Since smaller amounts are difficult to dispense and dose accurately, it is preferred that the beverage precursor has a mass of at least 1 g. More preferably, the mass is at least 1.2g, and most preferably at least 1.4 g. It is further preferred that the mass of the beverage precursor is less than 4g, as larger quantities become inconvenient to store and/or handle. More preferably, the mass is less than 3.5g, and most preferably less than 3 g.

The inflatable infusion bag preferably has a first geometry in its permanently compressed state and a second geometry in its inflated state. Although the second geometry may be an expanded version of the first geometry, it is preferred that the first and second geometries are different. In other words, the infusion bag preferably has a particular geometry in a permanently compressed state and transitions to an expanded state in which a different geometry is employed.

For example, the infusion bag may have a substantially disc-shaped cylindrical configuration in the compressed state (i.e., the first geometry is cylindrical) and then transition to have a substantially tetrahedral configuration in the expanded state upon addition of water (i.e., the second geometry is tetrahedral).

The first geometry preferably has a first face and a second face connected along a length (L), wherein the cross-section along the length (L) is constant and the shape is the same as the first face and the second face. The first and second faces are preferably parallel to each other.

Preferably, the first geometry is cylindrical or prismatic.

When the first geometry is cylindrical, the first face and the second face are circular or elliptical and are connected by a curved surface along the length (L).

When the first geometry is prismatic, the first face and the second face are polygonal and are connected along the length (L) by a plurality of joining faces, which are delimited from each other by a plurality of joining edges. The engaging surface is preferably square or rectangular (i.e. the prism shape is preferably a straight prism). However, it should be understood that in a less preferred configuration, the faying surface may be a parallelogram (i.e., the prism may be a tilted prism).

The first and second faces may have any simple polygonal shape (i.e., a shape in which the boundaries of the polygon do not intersect with themselves); thus, the polygonal shape may be concave or convex. Non-limiting examples of suitable polygonal shapes include: triangular, quadrilateral, pentagonal, hexagonal, heptagonal, octagonal, nonagonal, decagonal, and the like.

The geometry and dimensions of the infusion bag in its permanently compressed state will determine how efficiently a plurality of such bags may be packaged.

The first geometry preferably has a width (W), wherein the width (W) is greater than or equal to the length (L).

The width (W) is the widest dimension of the first or second face in a plane perpendicular to the length (L). For example, for a cylindrical shape having a circular cross-section, the width (W) is the diameter of the circular cross-section, while for a cylindrical shape having an elliptical cross-section, the width (W) represents the major axis of the elliptical cross-section. Similarly, for a prism shape having a square cross section, the width (W) represents a diagonal line of the square cross section.

The length (L) of the cylindrical or prismatic infusion packet in the permanently compressed state is preferably greater than 2mm, more preferably greater than 3mm, and most preferably greater than 4 mm. The length (L) is preferably no greater than 20mm, more preferably no greater than 18mm, and most preferably no greater than 16 mm.

The width (W) of the cylindrical or prismatic infusion packet in the permanently compressed state is preferably greater than 14mm, more preferably greater than 17mm, and most preferably greater than 20 mm. The width (W) is preferably not more than 45mm, more preferably not more than 40mm, and most preferably not more than 35 mm.

The inflatable infusion bag preferably has a second geometry in its inflated state. As mentioned above, the second geometry is preferably a different shape than the first geometry.

Embodiments are not excluded in which the second geometry is substantially flat (e.g. comprising a dip bag of infusible material sandwiched between square or circular sheets of porous material). However, such an embodiment is less preferred as this type of infusion bag is believed to limit the movement of the infusible material to substantially two dimensions, thereby limiting its infusion performance. Moreover, due to their substantially flat nature, packaging multiple infusion packets of this type has been relatively efficient.

Therefore, it is preferred that the second geometric shape is a three-dimensional shape. There is no particular limitation on the second geometry, and it may be any three-dimensional shape. However, it is desirable that the infusion bag having the second geometry be easily mass manufactured. Thus, preferred examples of the second geometric shape include shapes such as tetrahedrons, pyramids, hemispheres, spheres, cubes, and the like. It is particularly preferred that the second geometry is spherical, hemispherical, tetrahedral or pyramidal.

The present invention contemplates compressing a conventional infusion bag to achieve a form in which the infusion bag is in a permanently compressed state. Non-limiting examples of conventional infusion packets include spherical or hemispherical infusion packets such as those described in EP 0811562(Unilever), WO2012/095247(Unilever) or WO 2005/051797(Tetley) and tetrahedrally shaped infusion packets such as those described in WO 95/01907(Unilever), WO 2004/033303(IMA SPA) or WO 2012/004169 (Unilever).

The inflatable infusion bag preferably has a first geometry in its permanently compressed state and a second geometry in its inflated state. Although the second geometry may be an expanded version of the first geometry, it is preferred that the first and second geometries are different. In other words, the infusion bag preferably has a particular geometry in a permanently compressed state and transitions to an expanded state in which it has a different geometry.

The inflatable infusion bag has a volume V in a permanently compressed state_CAnd in the expanded stateHas a volume V_E. In order to achieve a significant reduction of the packaging space occupied by each compressed infusion packet without affecting the infusion performance, a significant increase in volume occurs when the infusion packet transitions from its permanently compressed state to its expanded state upon addition of water. Thus, V_EPreferably at least 2V_CMore preferably at least 2.5V_CAnd most preferably at least 3V_C. The expandable infusion bag should be capable of transitioning from its permanently compressed state to its expanded state upon addition of water in an efficient manner. Thus, V_EPreferably not more than 10V_CMore preferably not more than 8V_CAnd most preferably not more than 6V_C。

The inflatable infusion bag of the present invention may be made of any suitable material. Nonwoven materials are particularly preferred because these materials typically have relatively little "memory" in the fibers and therefore readily transition from a compressed state to an expanded state upon the addition of water. Non-limiting examples of nonwoven materials include nonwoven materials made from continuous filaments (e.g., PET, PLA, PP) and wet-laid nonwoven materials (e.g., a cellulose/polymer blend including cellulose and a polymer such as PP, PE, or PLA).

As discussed above, the geometry of an inflatable infusion bag in its permanently compressed state will determine how efficiently a plurality of such bags may be packaged. However, whatever particular geometry is chosen, the infusion bag of the present invention requires less storage space in its compressed state than in its expanded state.

The form of the package is not limited. For cost reasons it is preferred that the manufacture of the selected package is not overly complicated. From the viewpoint of simplicity, it is preferred that the package is a tube or a carton. Another benefit of this packaging solution is that the packaged product requires only a small amount of storage space in the consumer's home. Indeed, it is preferred that the secondary package be sufficiently compact that the infusion bag can be conveniently carried by the consumer or stored at work.

Examples of such tubular packages include cardboard, plastic or metal tubes with a suitably shaped cross-section. For example, if the compressed shape of an inflatable infusion bag is triangular in cross-section, a hollow tube having a triangular cross-section may efficiently package a plurality of such infusion bags. It is also contemplated that the tubular wrapper may be formed around the compressed infusion bag. For example, a plurality of compressed infusion packets may be arranged in a stack and packaged in a tubular manner by a sheet of flexible packaging material (e.g. paper or plastic) which is wrapped in a circumferential manner around the stacked infusion packets and sealed at the sheet edge junction (i.e. along the longitudinal direction such that the seal is substantially parallel to the length (L) of the compressed infusion packets).

In a preferred embodiment, the package is a tube and the first geometry is cylindrical (i.e., the inflatable infusion bag has a substantially disc-shaped cylindrical configuration in a permanently compressed state).

The tube need not have the same cross-section as the inflatable infusion bag. Thus, in embodiments where the package is a tube and the first geometry is cylindrical, the tube may have a circular or elliptical cross-section and thus match the cross-section of the first geometry.

Alternatively, the cross-section of the tube may not match the cross-section of the first geometry. In such embodiments, the space between the infusion bag and the tube is believed to assist in removing the infusion bag from the carton (by allowing the consumer to easily grasp the curved surface of the infusion bag). Tubes having a square or rectangular cross-section are particularly preferred because of the ease of manufacture of such cartons.

It will be appreciated that similar effects may be achieved with other dip bag shapes. For example, an inflatable infusion bag in which the first geometry is a hexagonal prism may be packaged in a tube having a square cross-section or the like.

As mentioned above, the secondary package may be a carton. The above-described tubular form relates to a packaging solution for compressing a stack of infusion packets. Rather, cartons provide a solution for packaging compressed infusion packets or rows (where each layer or row includes two or more compressed infusion packets). The compressed infusion packets may be packaged in this manner regardless of the first geometry of the infusion packet. For maximum packaging efficiency, it is preferred that the first geometry is fully interlocking. However, this is not a necessary requirement and a non-fully fitted shape will also be more efficiently packaged than a conventional non-compressed infusion packet. Furthermore, the spaces between the rows of compressed infusion packets having a non-fully tessellated shape may facilitate convenient removal of individual infusion packets from the carton by the consumer.

In a preferred embodiment, the package is a carton and the first geometry is square or rectangular prismatic (i.e., the inflatable infusion packet assumes a prismatic configuration having a square or rectangular cross-section in a permanently compressed state).

In another preferred embodiment, the package is a carton and the first geometry is cylindrical (i.e., the inflatable infusion packet assumes a cylindrical configuration having a substantially disc shape in a permanently compressed state). Cartons having a square or rectangular cross-section are particularly preferred because of the ease of manufacture of such cartons. The space between the infusion packet row and the carton is believed to assist in removing the infusion packet from the carton (by allowing the consumer to easily grasp the curved surface of the infusion packet).

In particular, the invention relates to a method comprising the following steps:

(a) providing an infusion bag in an expanded state;

(b) inserting the soak bag into a mold;

(c) pressure is applied to transform the infusion bag into a permanently compressed state.

As already discussed, the present invention contemplates compressing a conventional infusion bag to achieve a form in which the infusion bag is in a permanently compressed state. Thus, the infusion packet provided in step (a) is preferably a conventional infusion packet and may be manufactured by any known method. A tetrahedral shaped infusion bag is particularly preferred.

Inserting the infusion package provided in step (a) into a mould. Preferably, the mould is metallic, for example it may conveniently be made of steel.

The pressure applied in step (c) is preferably 3000 to 4200kPa, more preferably 3100 to 4100 kPa. Factors that affect the appropriate pressure include the type of material from which the infusion bag is made and the size/weight of the infusion bag. The pressure applied in step (c) is generally higher where a greater degree of compression is required and lower where a lesser degree of compression is required.

The pressure is preferably applied via a piston fitted in the mould. Preferably, the piston is metal, for example it may conveniently be made of aluminium. The mold and the piston are preferably made of different metals.

It will be appreciated that the amount of infusible material contained within the infusion bag has a given volume (e.g. the volume occupied by 3g of infusible material will be greater than the volume occupied by 2g of infusible material). As a general rule, the more infusible material contained within an infusion bag, the greater the volume that infusible material occupies. Thus, infusion packets that include a greater amount of infusible material will generally be compressed to a lesser extent than infusion packets that include a lesser amount of infusible material.

In another aspect, the present invention relates to an inflatable infusion bag according to the first aspect of the invention, wherein the inflatable infusion bag is obtainable by the method of the third aspect of the invention. In other words, an inflatable infusion packet, wherein the infusion packet is in a permanently compressed state in the absence of water and is transformed into an inflated state in the presence of water, is obtainable by a process comprising the steps of: (a) providing an infusion bag in an expanded state; (b) inserting the soak bag into a mold; (c) pressure is applied to transform the infusion bag into a permanently compressed state.

Drawings

The invention is described, by way of example, with reference to the following drawings, in which:

FIG. 1a is a perspective view of an inflatable infusion bag in a permanently compressed state;

FIG. 1b is a perspective view of the inflatable infusion bag of FIG. 1a in an inflated state;

FIG. 2a is a perspective view of a compressed infusion packet according to the invention, which has been placed in a receptacle ready for infusion;

FIG. 2b is a schematic view of the infusion packet of FIG. 2a with water added to the container for preparing a beverage;

FIG. 3a is a perspective view showing the arrangement of a plurality of compressed infusion packets;

FIG. 3b is a perspective view showing one embodiment of a package comprising a plurality of compressed infusion packets;

FIG. 3c is a perspective view showing an alternative embodiment of a package comprising a plurality of compressed infusion packets;

FIG. 4 shows a series of perspective views illustrating possible shapes of an inflatable infusion bag in its permanently compressed state in accordance with the present invention;

FIG. 5a is a perspective view of an infusion bag having a hemispherical expanded state;

FIG. 5b is a perspective view of the infusion bag having a cubical expanded state;

FIG. 6 is a perspective view showing a carton including a plurality of compressed infusion packets;

FIG. 7 shows a different arrangement of a plurality of compressed infusion packets;

figure 8 is a perspective view showing a carton including a plurality of compressed infusion packets.

Detailed Description

FIG. 1a shows an inflatable infusion bag in accordance with the invention in its permanently compressed state. The compressed infusion bag (1) is cylindrical and has a circular cross-section. In this form, the infusion bag has a circular first face (2) and a circular second face (opposite the first face and therefore not visible in fig. 1 a) connected along the length (L) by a curved surface (4). The cross-section along the length (L) is constant and the same shape as the first and second faces (i.e. circular). In the illustrated embodiment, the width (W) is the diameter of the circular cross-section.

FIG. 1b shows the infusion packet of FIG. 1a in an expanded state. The expanded infusion packet (5) has adopted a three-dimensional tetrahedral shape. Thus, the infusion bag has a different shape in its expanded state than in its compressed state. The three-dimensional expanded state allows the infusible material (6) space to move within the infusion bag (5), which is believed to improve infusion performance.

FIG. 2 illustrates the transition of an inflatable infusion bag according to the invention from its permanently compressed state to its inflated state. This transformation occurs under conditions typically used by consumers to prepare infusions from conventional infusion packets.

Figure 2a shows the infusion packet before infusion begins. The compressed infusion packet (1) has been placed in a container (7), in this case a cup, suitable for receiving a quantity of hot water. To prepare a beverage from a compressed infusion packet, the consumer adds hot water to the container. The infusion bag is transformed into an expanded state in the presence of water (8). The amount of water that consumers use to prepare beverages from conventional infusion packets varies and is not geographically constant. Thus, it is preferred that the amount of water that will cause the infusion bag to transition from its permanently compressed state to its expanded state is not significant, although it will be appreciated that this volume is typically greater than V_E(100ml of water is usually sufficient). Figure 2b shows the infusion packet during infusion. The infusion bag is now in its expanded state (5) and has adopted a three-dimensional tetrahedral shape.

The compressed infusion packets of the present invention may be conveniently packaged as shown in figure 3.

Figure 3a shows a plurality of compressed infusion packets (1), the compressed infusion packets (1) being stacked on top of each other. This arrangement results in a form with a constant cross-section (in this case a circular cross-section) since the infusion bag has a regular shape in the compressed state.

Figure 3b shows a possible way of packaging a plurality of compressed infusion packets (1). The stack of inflatable infusion packets is held together by a secondary packaging (9). In fig. 3b, the secondary package (9) is tubular and takes the form of a sheet (e.g. formed of paper or plastic) which extends in a circumferential manner around the infusion bag and is sealed at its edge junction.

Figure 3c shows an alternative way of packaging a plurality of compressed infusion packets (1). In fig. 3c, the secondary package (9) is a cardboard tube with a square cross-section. This carton is in the form of a square prism. Although the compressed infusion packets do not fill the entire volume of the carton, packaging efficiency is still improved (i.e. a carton designed to hold the same number of conventional infusion packets in expanded form will have a significantly greater volume).

Although not shown, it should be understood that a greater variety of secondary packaging forms are possible (e.g., cardboard or plastic tubing, etc.).

The shape of the inflatable infusion bag in its permanently compressed state may be prismatic. Fig. 4 shows some possible prismatic configurations.

In fig. 4a, the compressed infusion bag is in the form of a triangular prism. In this form, the first and second faces of the infusion bag are triangular and connected along the length (L) by three rectangular engagement faces (11), the three rectangular engagement faces (11) being delimited from each other by three engagement edges (12). In this embodiment, the width (W) is the distance between two adjacent vertices of the triangular cross-section.

In fig. 4b, the compressed infusion bag is a square prism. In this form, the first and second faces of the infusion bag are square and are connected along the length (L) by four rectangular engagement faces (11), the four rectangular engagement faces (11) being delimited from each other by four engagement edges (12). In this embodiment, the width (W) is the diagonal of the square cross-section.

Fig. 4c and 4d show two possible hexagonal prism configurations for the compressed infusion packet. In both cases, the first and second faces of the infusion packet are hexagonal and connected along the length (L) by six rectangular joining faces (11), the six rectangular joining faces (11) being delimited from each other by six joining edges (12). The compressed infusion bag of figure 4c has a convex hexagonal cross-section, whereas the compressed infusion bag of figure 4d has an L-shaped concave hexagonal cross-section.

The shape of the inflatable infusion bag in its inflated state is not limited and may be any geometric shape. Fig. 5 shows some possible configurations.

In fig. 5a, the inflated infusion bag (5) is in the shape of a three-dimensional hemisphere, whereas in fig. 5b it is in the shape of a cube in its inflated form.

It should be understood that there is no particular relationship between the shape of the inflatable infusion bag in its compressed state and its inflated shape. In particular, an infusion bag having any of the expanded shapes shown in fig. 1b, 5a and 5b may be compressed so as to have any of the configurations shown in fig. 1a, 4b, 4c and 4 d.

The shape of the infusion packet in its compressed state may be used as a code to help the consumer identify the appropriate product. For example, a range of products are typically sold by a particular manufacturer (e.g., green tea, black tea, fruit and herbal infusions, etc.). Typically, each member of the series uses the same shape of infusion bag (e.g., tetrahedron). Each type of product is sold in a separate package (e.g., a carton containing a number of infusion packets) and the information provided on the package identifies the particular product type. The invention allows each product in the series to have a different shape in the permanently compressed state (while still maintaining a common shape in the expanded state). For example, infusion packets containing black tea may have a cylindrical shape, while those containing green tea may have a hexagonal prismatic shape, and so on. In this way, the consumer is still able to visually identify each product in the series even though the compressed infusion packets have been removed from the package in which they were sold.

Figure 6 shows a possible way of packaging a plurality of compressed infusion packets. In the figure, a plurality of compressed infusion packets (1) are arranged inside a cardboard carton (15). The square cross-section of the infusion packets (1) means that they are completely nested, thus allowing a very efficient use of the internal space within the carton.

Figure 7 shows a different arrangement of a plurality of compressed infusion packets. Figure 7a shows a plurality of compressed infusion packets (1) with hexagonal cross-section, which plurality of compressed infusion packets (1) have been stacked on top of each other. The regular shape of these infusion packets in the compressed state means that the infusion packet stack has a constant cross section. The stack of inflatable infusion packets may be packaged to maintain this arrangement (e.g. in a similar manner to that shown in figure 3 b).

Figure 7b shows an alternative arrangement of a compressed infusion bag (1) having a hexagonal cross-section. In this arrangement, the compressed infusion packets are arranged in a single layer. The regular hexagonal cross-section of the infusion packets (1) means that they are completely nested. The expandable infusion packets may be packaged to maintain this arrangement (e.g., by packaging them in a paperboard carton).

Figure 8 shows a possible way of packaging a plurality of compressed infusion packets. In the figure, a plurality of compressed infusion packets (1) are arranged inside a cardboard carton (15). The circular cross-section of the infusion packets (1) means that they are not completely nested. However, the compressed infusion packets are still packaged very efficiently, while the small amount of space around the compressed infusion packet allows the consumer to easily remove the individual infusion packets by grasping their curved surfaces.

Although not shown, it should be understood that the final packaging arrangement may include multiple layers of compressed infusion packets. Indeed, it is also envisaged that each layer of infusion packets may have a different shape in the compressed form. For example, the first layer may consist of a dip bag having a hexagonal cross-section, while the second layer consists of a dip bag having a square cross-section.

Examples of the invention

A commercially available PG Tips pyramid tea bag (bag weight about 2.9g) was provided. The tea bag is substantially tetrahedral in shape (approximately 65mm side length) in the expanded state. Volume (V) of the tea bag in the expanded state_E) About 32365mm³。

The tea bag is inserted into a steel mold in the shape of a hollow cylinder and is transformed into a permanent compression state by applying a pressure of 500psi (about 3447kPa) via an aluminum piston sliding within the cylinder mold, thereby compressing the tea bag. The tea bag is substantially cylindrical in shape (having a circular cross-section) in a permanently compressed state. The compressed cylindrical form of the tea bag has a width (W) of about 34mm and a length (L) of about 7.5 mm. Volume (V) of the tea bag in a permanently compressed state_C) About 6809mm³。

The permanently compressed tea bag was placed in an empty cup and 200ml of hot water was added. The tea bag is converted into an expanded form within a few seconds. Moreover, this transformation causes the tea bag to "tumble". This movement helps to rapidly brew the tea leaves contained within the tea bag without the need to stir or otherwise agitate the tea bag.

For comparison, an uncompressed commercial PG Tips pyramid tea bag (bag weight about 2.9g) was placed in an empty cup and 200ml of hot water was added. The addition of water resulted in a temporary flattening of the tea bag. Furthermore, although the tea bag floats once the water is added, it does not "tumble" and is substantially stationary during brewing. The lack of movement means that the tea contained in the tea bag does not brew as quickly as possible.

Claims

1. An inflatable infusion bag wherein the infusion bag is in a permanently compressed state in the absence of water and transforms to an inflated state in the presence of water and wherein the infusion bag has a substantially rigid structure in the permanently compressed state that does not deform upon handling.

2. The inflatable infusion bag of claim 1, wherein the infusion bag has a volume, V, in the permanently compressed state_CAnd has a volume V in the expanded state_EAnd wherein V_EIs 2V_CTo 10V_C。

3. The inflatable infusion bag of claim 1 or 2 wherein the infusion bag has a first geometry in its permanently compressed state and a second geometry in its inflated state, wherein the first and second geometries are different.

4. The inflatable infusion packet of claim 3, wherein the first geometric shape is cylindrical.

5. The inflatable infusion packet of claim 3, wherein the first geometric shape is prismatic.

6. The inflatable infusion packet of claim 3, wherein the second geometric shape is a sphere, a hemisphere, a tetrahedron, or a pyramid.

7. An inflatable infusion bag according to claim 1 or 2, wherein said infusion bag is made of a non-woven material.

8. A package comprising a plurality of inflatable infusion packets as claimed in any one of claims 1 to 7.

9. The package of claim 8, wherein the package is a tube or carton.

10. The package of claim 9, wherein the infusion packet has a first geometry in its permanently compressed state, the package is a tube and the first geometry is cylindrical.

11. The package of claim 9, wherein the infusion packet has a first geometry in its permanently compressed state, the package is a carton and the first geometry is a square or rectangular prism.

12. The package of claim 9, wherein the infusion packet has a first geometry in its permanently compressed state, the package is a carton and the first geometry is cylindrical.

13. A method of manufacturing an inflatable infusion packet as claimed in any of claims 1 to 7, the method comprising:

(a) providing an infusion bag in an expanded state;

(b) inserting the infusion bag into a mold;

(c) applying pressure to transform the infusion bag into a permanently compressed state, wherein the infusion bag has a substantially rigid structure in the permanently compressed state that does not deform upon handling.

14. The process of claim 13, wherein the pressure applied in step (c) is 3000 to 4200 kPa.