Abstract
A three-compartment water-soluble capsule, each compartment containing a part of a liquid detergent composition, the compartments being arranged side-by-side to provide a central compartment flanked on respective sides by a first and a second side compartment, the capsule being formed from two sheets of water-soluble film, the two sheets of film being sealed together to form a sealing web around each compartment, the sealing web lying in a sealing plane, each of the three compartments extending at a maximum the same distance above and below the sealing plane, wherein the sealing web comprises an annular sealing web defining the periphery of the capsule, and two internal sealing webs which each extend across the capsule, each internal sealing web serving to connect the central compartment with an adjacent side compartment and to separate their contents, wherein each internal sealing web has a continuously curved shape.
Claims
1. A three-compartment water-soluble capsule, each compartment containing a part of a liquid detergent composition, the three compartments being arranged side-by-side to provide a central compartment flanked on respective sides by a first side compartment and a second side compartment, the capsule being formed from two sheets of water-soluble film, the two sheets of film being sealed together to form a sealing web around each compartment, the sealing web lying in a sealing plane, each of the three compartments extending at a maximum the same distance above and below the sealing plane, wherein the sealing web comprises an annular sealing web defining the periphery of the capsule, and two internal sealing webs which each extend across the capsule in a machine direction, each internal sealing web serving to connect the central compartment with an adjacent side compartment and to separate the contents of the central and adjacent side compartments, wherein each internal sealing web has a curved shape, wherein each internal sealing web is free of straight portions, wherein the spacing between the two internal sealing webs decreases as the internal sealing web traverses the capsule from an outer position where the spacing is integral with the annular sealing web to a radially inner position at the midpoint of the length of the internal sealing web.
2. A three-compartment water-soluble capsule according to claim 1, wherein at least a portion of each internal web has a curved profile whose radius of curvature is in the range 12 mm to 22 mm.
3. A three-compartment water-soluble capsule according to claim 1, wherein the width of each internal sealing web is constant and wherein the width of each internal sealing web is ≤3 mm.
4. A three-compartment water-soluble capsule according to claim 1, wherein the extent of reduction of spacing between the two internal sealing webs is in the range 6 to 12 mm.
5. A three-compartment water-soluble capsule according to claim 1, wherein the capsule has second order rotational symmetry.
Description
DESCRIPTION OF EMBODIMENTS
(1) The invention will now be further described with reference to the following non-limiting embodiments and with reference to the drawings, of which:
(2) FIG. 1 is a prior art two-compartment capsule, being a reproduction of FIG. 1A of EP1394065;
(3) FIG. 2 is a prior art two-compartment capsule, being a reproduction of FIG. 7 of WO2014/202412;
(4) FIG. 3 is a schematic representation of a prior art three-compartment capsule available from El Corte Ingles (Spain);
(5) FIG. 4 is a perspective view of a capsule in accordance with the present invention;
(6) FIG. 5 is a top plan view of a capsule in accordance with the present invention;
(7) FIG. 6 is a cross-sectional view of the capsule illustrated in FIG. 5, taken along line II-II in FIG. 5;
(8) FIG. 7 is a side elevational view of the capsule illustrated in FIGS. 6 and 7;
(9) FIG. 8 is a perspective view of a three-cavity mould in accordance with the present invention;
(10) FIG. 9 is a perspective view of a rotary cylindrical drum comprising an array of hexagonal moulds on the surface;
(11) FIG. 10 is a alternate perspective view of the rotary cylindrical drum of FIG. 9;
(12) FIG. 11 is a side view of the rotary cylindrical drum of FIG. 10;
(13) FIG. 12 is a schematic illustration of the configuration of cavities in the mould of FIG. 8; and
(14) FIG. 13 is a schematic illustration of an alternative configuration of cavities in a mould.
(15) Each of the figures will now be discussed in turn.
(16) FIGS. 1, 2 and 3 have already been discussed. Similarly, FIG. 4 has already been discussed.
(17) Turning now to consider FIGS. 5 to 7, there is illustrated a further capsule 501 in accordance with the present invention, which capsule is largely identical to that the capsule shown in FIG. 4.
(18) The capsule 501 comprises three discrete compartments 502, 503, 504, each of which defines a respective substantially liquid-tight and hermetically sealed chamber containing a respective volume 505, 506, 507 of liquid product, as denoted schematically by the cross-hatched areas in FIG. 6. The compartments are arranged adjacent one another, side-by-side in a notional row, as will be described in more detail hereinafter. A central compartment 502 is thus located between a pair of side compartments 503, 504.
(19) As will be appreciated, each compartment 502, 503, 504 is defined between the upper and lower layers of PVA film, and is sealed around its respective periphery by the fusion of the two layers of film therearound. More particularly, and having regard to FIG. 5, it will be noted that the upper and lower film layers are fused together around the three compartments to form a generally annular web 508 extending around all of the compartments 502, 503, 504, and which has a hexagonal outer edge 509, as defined by the aforementioned cutting process. The upper and lower film layers are also fused together to form a pair of thin additional webs 510 which are formed integrally with the annular web 508 and which extend across the capsule 501 in spaced-relation to one another. Each of the additional webs 510 serves to separate the central compartment 502 from a respective side compartment 503, 504.
(20) As will be noted most clearly from FIG. 5, the central compartment 502 is substantially larger than the two side compartments 503, 504. The central compartment 502 may thus be considered to define a primary chamber, whilst the two side chambers 503, 504 may be considered to define respective secondary chambers. It is envisaged that in some embodiments, the two side compartments 503, 504 may be of equal size and volume. In the particular embodiment illustrated, the central compartment 502 is configured to hold a larger volume of liquid product 505 than each of the two side compartments 503, 504. In particular embodiments, it is envisaged that the volume of liquid product 5 provided within the central compartment 502 may be approximately three times greater than the volume of liquid detergent product 506, 507 provided in each of the side chambers 503, 504. As illustrated in FIG. 6, a respective small volume of air 511, 512, 513 may become trapped inside each compartment 502, 503, 504 during the manufacturing process.
(21) As shown most clearly in FIG. 5, the central compartment 502 has a somewhat S-shaped profile in plan view, defining a relatively narrow central region 514 which interconnects a pair of relatively wide end regions 515. The relatively narrow central region 514 is defined between a pair of opposed side edges 516 of the central compartment, the side edges 516 being defined by the respective additional webs 510, Each of the side edges 516 are shaped so as to comprise a respective convex portion 517 and a respective concave portion 518. The concave portion 518 of each side edge 516 serves to define a recess along each side of the central compartment 502.
(22) As also shown most clearly in FIG. 5, each side compartment 503, 504 is shaped so as to locate, at least partially, within a respective one of the above-mentioned recesses defined along the sides of the central compartment 502. In this regard, it is to be noted that each side compartment 503, 504 has a somewhat teardrop-shaped profile in plan view, defining a relatively bulbous region 519 at one end, and a relatively narrow and somewhat pointed region 520 at the opposite end. Because the central compartment 502 is somewhat S-shaped in profile as described above, in order to locate within the aforementioned recesses, the two side compartments 503, 504 are inverted relative to one another such that the bulbous region 519 of the left-hand side compartment 503 is located adjacent one end region 515 of the central compartment 502, and the bulbous region 519 of the right-hand side compartment 504 is located adjacent the opposite end region 515 of the central compartment 502. As will thus be noted, the bulbous region 519 of each side compartment is positioned adjacent the concave region 518 of a respective side edge 516 of the central compartment 502, whilst the opposite pointed region 520 of each side compartment is positioned adjacent the convex region 517 of the respective side edge 516 of the central compartment 502. Respective inwardly directed side edges 521 of the two side chambers 503, 504 are arranged adjacent, and in facing relation to, the side edges 516 of the central compartment 502 and have a substantially identical profile, such that the additional webs 510 of fused material which separate each side compartment 503, 504 from the central compartment 502 are of substantially uniform width along their length.
(23) The central compartment 502 presents a pair of outwardly directed end edges 522 at its oppositely directed ends, and each side compartment 503, 504 presents a respective outwardly directed side edge 523. Because of the above-described manner in which the teardrop-shaped side chambers 503, 504 locate at least partially within the recesses formed along the sides of the S-shaped central compartment 502, it will thus be appreciated that the outwardly directed edges 522, 523 of the compartments cooperate in a generally contiguous and approximate manner to define a notional circle 524, as denoted in phantom in FIG. 5.
(24) Turning now to consider FIG. 7, the capsule 501 is illustrated in side profile. As will be noted, the end regions 515 of the central compartment 502 are somewhat larger in vertical dimension than the central region 514, due to the fact that the end regions 515 are of course more volumous than the central region 514. A small depression or recess 525 is thus formed on the top and the bottom of the central compartment 502.
(25) As also illustrated in FIG. 7, each side chamber 503, 504 (only one being shown in FIG. 3) is configured such that its maximum depth in side profile coincides with its bulbous, and thus most volumous, region 519. The side chambers 503, 504 each narrow in side profile depth from the bulbous region to the relatively narrow and somewhat pointed end region 520. In preferred embodiments, it is envisaged that the maximum side profile depth of each side chamber 503, 504 will be less than or substantially equal to the minimum side profile depth of the central chamber 502, as illustrated.
(26) Production
(27) FIG. 8 shows a mould or cavity section 601 used to thermoform a first film to manufacture a three-compartment capsule of the present invention. The mould 601 has a hexagonal shape (six equal length external side walls 605 defining a hexagon), which permits it to tessellate in a hexagonal array of identical moulds. The mould has a first teardrop-shaped side cavity 602, an S-shaped central cavity 603, and a second teardrop-shaped side cavity 604. The second teardrop-shaped cavity 602 is inverted with respect to the first teardrop-shaped cavity 603. Each cavity is provided with a number of ducts (not shown) to which may be applied a vacuum.
(28) FIG. 9 shows a plurality of such hexagonal moulds/cavity sections 601 arranged in a regular array on the outside of a rotary cylindrical drum 606. The hexagonal moulds are arranged in columns.
(29) FIG. 10 shows the rotary cylindrical drum 606 of FIG. 9 from a different perspective. Here the array 607 is illustrated schematically with simple squares. The drum has a horizontal axis 608.
(30) FIG. 11 shows the rotary cylindrical drum 606 from the side. The first film 609 is fed from a supply roll (not shown) over a heating roller (not shown) which has a nominal surface temperature of between 90 and 150° C. When the first film used is for example Aicello PT90 the heating roller temperature is maintained between 120 and 140° C. Immediately after passing over the heating roller, the hot base film is fed onto the cavity section which is part of an array of such moulds around a rotary drum.
(31) Rotation of the cylinder so the cavities reach point 610 ensures that the heated first film fully covers the cavities in the cavity section. At point 705 a vacuum is then applied to the cavity section through its ducts. The vacuum is applied simultaneously to all the ducts. The vacuum pulls the first film into the cavities 602, 603 and 604 (as shown in FIG. 8) and holds it there. The film typically retains some elasticity at this stage. This leads to a tighter capsule which is preferred for ongoing line handling and robustness as well as consumer perception.
(32) Once the cavities are thermoformed and held in place with the vacuum, the three compartments 602, 603, 604 are filled. Filling is done at the apex of the cylinder 611.
(33) The liquid composition dispensed to each of the three compartments is as follows:
(34) TABLE-US-00001 Side compartment #1 Central compartment Side compartment #2 Surfactant Surfactants Surfactants Polymer cleaning Polymer cleaning Polymer cleaning Sequestrant Sequestrant Sequestrant Water Enzymes Water Hydroptrope Fluorescer Hydrotrope Opacifier Water Dyes Hydrotrope Dyes Perfume
(35) In other embodiments, the composition of side compartment #1 was modified so as to include encapsulated perfume.
(36) The composition of side compartment #1 is formulated, including through the use of an opacifier, so as to provide a white opaque composition. The central compartment is formulated, including provision of suitable dyes, to provide a blue colour. Side compartment #2 is formulated, including provision of suitable dyes, to provide a purple colour.
(37) Fill volume vs. brimful volume is aimed at a minimum of 80%. For example, for a 28 ml liquid fill the cavity volume is thus at most 35 ml.
(38) The volume of side compartment #1 is approximately 6 ml. The volume of side compartment #2 is also approximately 6 ml. The volume of the central compartment is approximately 18 ml.
(39) Filing of the central compartment 603 starts shortly before filling of the side compartments. This is done because the central compartment arrives under the filling station at the apex 611 just before the side compartments, by virtue of the central compartment being longer than the side compartments, and the orientation of the compartments with respect to the drum rotation direction such that the long axis of the compartments is aligned with the drum rotation direction, as shown in FIG. 9. The alignment of the three compartments (strictly the three cavities that will form the compartments) is also shown in FIG. 12.
(40) The filling station provides three filing nozzles, each one addressing respective first side, central and second side compartments.
(41) The three filling nozzles are arranged side-by-side in a line, which line is perpendicular to the drum rotation direction.
(42) In other arrangements, one of the filling nozzles may be stepped forward or backward from the line, for example by a distance that corresponds to the spacing, in the drum rotation direction, between the leading edges of the side and central compartments. For example, the central compartment filling nozzle may be stepped back from the two side compartment filling nozzles such that the leading edge of each of the three compartments arrives under their respective filling nozzles at substantially the same time.
(43) In the case of the preferred in-line arrangement, the central compartment will arrive under its filling nozzle earlier than will the respective side compartments. This can be understood from FIG. 12, where the direction of travel 620 is shown. Thus, advantageously, filling of the central compartment can commence before filling of the side compartments. To facilitate this, the central compartment filling nozzle is controlled so that it can operate (i.e. dispense liquid composition) independently of the side compartment filling nozzles. Alternatively or additionally the operation of the central compartment filling nozzle is controlled so that it begins dispensing at a different time, suitably before and suitably a predetermined time before, the side compartment filling nozzles. The operation of the central and side compartment nozzles may therefore be synchronised to provide this staggered (in time) dispensing.
(44) The apparatus comprises a nozzle control system configured to provide said control of the central compartment filling nozzle.
(45) Similarly, the length of time for which the central compartment filling nozzle is activated (i.e. is dispensing liquid composition) may be controlled so as to be different to the corresponding activation time (dispensing time) of the side compartment filling nozzles.
(46) In particular, taking into account the larger volume and/or greater length (aligned with the drum rotation direction) of the central compartment as compared to the side compartments (see FIG. 12), the central compartment filling nozzle is controlled so as to have a longer activation (dispensing) time. This permits, for example, the central compartment to be filled for longer, and hence deposit a larger amount of liquid composition. Thus, a longer “fill zone” 621 for the central compartment 603 is achieved as compared to the fill zone 622 for the side compartments 602, 604, as shown in FIG. 12.
(47) An alternative capsule (mould) arrangement 701 is shown in FIG. 13, whereby the three compartments 702, 703, 704 have the same general configuration and relationship as discussed for FIG. 12, such that the fill zone 705 for the central compartment 703 is considerably longer than the fill zone 706 for the side compartments 702, 704. Again, this achieved by independent control of the filling nozzles.
(48) As described herein, the fill rate for the central compartment filling nozzle may be different from, for example greater than, the fill rate of the side compartment filling nozzles.
(49) Returning to FIG. 11, immediately after filling of the liquid compartment the second film 612 is brought into position over the filled cavities. Immediately before this the second film has been passed through a water bath (not shown). This makes the lower surface of the second film 612 wet which acts as the mechanism for sealing the second film to the first film where it contacts it; thus forming the seal areas. The second film is a similar type to that used for the first film but is the slightly thinner, for example 60 micron Aicello. The seal area is made secure by pressure application of a sealing roller at position 613.
(50) Post sealing, the filled capsule is cut from the sheet at position 614. This is achieved by horizontal and inclined cuts from cylindrical cutter 615 (shown in FIG. 10). Thus, the horizontal cuts correspond to the horizontal (perpendicular to the direction of travel) opposing sides of the hexagons as shown in FIG. 9, and the included cuts correspond to the other tow pairs of opposing sides, being inclined as shown in FIG. 9. For those embodiments where a square or rectangular footprint is desired, only horizontal cuts may be provided by the cylindrical cutter 615. Vertical cuts, if required (e.g. for square cutting pattern) are provided by static knife blades 616.
