Nozzle assembly for producing center-filled goods

Abstract

A nozzle assembly for co-extruding two liquids at a high temperature, the nozzle assembly comprising: an outer nozzle jacket having a first terminus; and an inner nozzle having a second terminus, wherein the inner nozzle is disposed within the outer nozzle jacket, the second terminus of the inner nozzle extends further than the first terminus of the outer nozzle jacket; and a process for co-extruding two liquids, thereby forming a center-filled good.

Description

[0001] NOZZLE ASSEMBLY FOR PRODUCING CENTER-FILLED GOODS

[0002] FIELD OF THE INVENTION

[0003] The present invention relates to a nozzle assembly for producing center-filled goods. The present invention particularly relates to nozzle assembly for co-extruding liquids with improved process control. The invention further relates to the process and inner nozzle.

[0004] BACKGROUND

[0005] In the mass production of center filled confections such as gummy, also known as jelly candy or fruit snacks using starch deposition equipment or methods, a low viscosity during deposition is desirable to avoid "candy tailing." The problem of candy tailing is a phenomenon where a string of product runs from one deposit to the next, thereby inter-linking the desired individual sweets or pieces of confection. An additional problem in the production of center-filled products is an off-centered filling which results in a portion of the shell being thin and subject to breakage. A troublesome problem with off-centered product is that the pieces are more prone to leakage. Off-centered products tend to result in "leakers" or product in which the center or filler component leaks out of the shell or is exposed due to weakness or thin spots in the shell.

[0006] Excessively thin walls resulting from off-centered fillers may also limit the shapes into which the product can be molded, and may also limit the amount of filling because during deposition and molding, the generally cylindrical shape of the shell may be substantially changed. The change in shell shape for enrobing of the filler, and the change in shape to fill a mold cavity may further thin the shell walls.

[0007] The thinning problem may be further exacerbated when depositing into a mold cavity having a disproportionally longer vertical dimension or greater depth, than horizontal dimension, or width or vice versa (i.e., tall and slender or short and wide). For a given piece weight, when depositing into a cavity of these proportions there is less leeway for increasing the shell flow rate so as to create thicker shell side walls because the surface area of the piece (both shell and center) is much greater. To obtain thicker walls it may necessary to substantially reduce the amount of filler, thereby detracting from the sensation of a different texture or liquid center. The leakage problem is of particular concern in the production of liquid or fluid filled confections. Leakage creates a sticky product and detracts from the liquid center sensation. The leakage may occur during material handling processes inherent in the manufacture of gummy or jelly sweets or fruit snacks. For example, leakage may occur after molding during oiling, polishing, and packaging operations as well as during transport and long term shelf storage in bags or pouches.

[0008] Another problem with off-centered products is that their appearance my be undesirable, even if the leaked filler is non-sticky. For example, for center filled products having a different colored or flavored center, the filler may be visible on the surface, or the different filler flavor may be tasted prematurely. Also, products having a transparent or translucent shell component and an off-centered filling may appear less attractive than a centered filler even if the filler has not leaked to the outer surface of the shell component.

[0009] Center filled confections are generally produced using commercially available Mogul or starch depositor equipment such as starch depositors manufactured by NID Pty. Ltd., Winkler and Dunnebier, and Werner Makat. In center fill manifold and nozzle combinations used for starch depositing, a center product or filler component runs down an inner tube down the center or middle of the manifold nozzle to near the extraction point of the nozzle. At this point it is surrounded by the shell component which has been flowing down the annular space in the nozzle between the nozzle outer wall and the inner tube. Generally, the manifolds are machined to have only one entry point for the shell component per cavity or nozzle.

[0010] However, it has been found that in the production of gummy or jelly candies or fruit snacks, as the shell portion is very fluid to avoid candy tailing, the shell component tends to preferentially flow down the side at which it was introduced into the annular space in the manifold. As a result, the center product is preferentially forced to the far side (side furthest away from the point of shell introduction in the manifold) in the stream emanating from the nozzle tip. This preferential flow of the shell component along the single side of introduction in the annular space and displacement of the filler by the shell component results in off-centered product. The loss in concentricity tends to be more pronounced when the viscosity of the filler component is substantially less than the viscosity of the shell component, such as in liquid center filled products. These issues are known within the field of confectionary, but apply mutatis mutandis to the field of pharmaceutical carriers. The present invention aims to resolve at least some of the problems and disadvantages mentioned above. The aim of the invention is to provide a method which eliminates those disadvantages. The present invention targets at solving at least one of the aforementioned disadvantages.

[0011] SUMMARY OF THE INVENTION

[0012] The present invention and embodiments thereof serve to provide a solution to one or more of the above-mentioned disadvantages. It should be noted that these solutions apply to the field of confectionary. However, by solving many of these problems, it makes center-filled products increasingly suitable as pharmaceutical carrier. In particular, a center-filled product comprising an amount of liquid or syrup, which may or may not further comprise active pharmaceutical ingredients (APIs). This advantageously provides both advantages of solid oral dosages, such as high control over the dosage regime of the patient and convenience of use, as well as syrups such as a mechanical component to the method of action, immediate relief and quick dispersion of the API within the syrup.

[0013] The present invention and embodiments thereof serve to provide a solution to one or more of above-mentioned disadvantages. To this end, the present invention relates to a nozzle assembly according to claim 1.

[0014] Preferred embodiments of the nozzle assembly are shown in any of the claims 2 to 10. A specific preferred embodiment relates to an invention according to claim 4. The particular nozzle shape is also shown in figures 4A and 4B and found highly desirable to improve control over the obtained center-filled good.

[0015] In a second aspect, the present invention relates to an inner nozzle according to claim 10. Preferred embodiments of the inner nozzle are shown in any of claims 11- 12.

[0016] In a third aspect, the present invention relates to a method for producing center- filled goods according to claim 13. Preferred embodiments of the method are shown in any of the claims 14 to 15.

[0017] DESCRIPTION OF FIGURES The following description of the figures of specific embodiments of the invention is merely exemplary in nature and is not intended to limit the present teachings, their application or uses. Throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features.

[0018] Figure 1 shows a schematic representation of the production process of center-filled goods through co-extrusion.

[0019] Figure 2 shows a nozzle assembly as per the prior art

[0020] Figure 3A shows a schematic representation of a center-filled good wherein the shell matrix has sufficient thickness an

[0021] Figure 3B shows a schematic representation of a center-filled good displaying phase dropping.

[0022] Figure 3C shows a schematic representation of a center-filled good displaying stringing.

[0023] Figure 4A shows a schematic representation of a preferred embodiment of an inner nozzle according to present invention.

[0024] Figure 4B shows a cross-section of a preferred embodiment of an inner nozzle according to present invention.

[0025] Figure 5 shows a schematic representation of a preferred embodiment of an outer nozzle according to present invention.

[0026] Figure 6 shows a schematic representation of an embodiment of a flow distribution body according to present invention.

[0027] Figure 7 shows an exploded representation of a preferred embodiment of the nozzle assembly according to present invention.

[0028] Figure 8A shows a schematic cross section of preferred embodiment of the nozzle assembly according to present invention.

[0029] Figure 8B shows a detailed representation of the schematic cross section of the nozzles of figure 8A.

[0030] List of reference signs :

[0031] 1 Nozzle assembly

[0032] 2 Inner nozzle

[0033] 3 Outer nozzle

[0034] 4 Inner passageway

[0035] 5 Annular passageway

[0036] 6 Inner nozzle terminus

[0037] 7 Outer nozzle terminus 8 Nozzle jacket

[0038] 9 Flow distributing protrusions

[0039] 10 Flow distributing apertures

[0040] 11 Flow distribution body

[0041] 12 Inner nozzle body

[0042] 13 Inner nozzle body receiver

[0043] 14 Inner nozzle body recess

[0044] 15 Connecting screws

[0045] 16 Connecting screw holes

[0046] 17 Nozzle thickness

[0047] 20 Shell matrix hopper

[0048] 21 Center-filler hopper

[0049] 22 Shell matrix melt

[0050] 23 Center-fill liquid

[0051] 24 Shell matrix plunger

[0052] 25 Center-fill plunger

[0053] 26 Manifold

[0054] 27 Shell matrix melt passageway

[0055] 28 Mold

[0056] 30 Center-filled good

[0057] 31 Shell matrix

[0058] 32 Center-fill

[0059] 33 Undesirable center-filled good

[0060] 34 Shell stringing

[0061] 35 Center-fill stringing

[0062] DETAILED DESCRIPTION OF THE INVENTION

[0063] The present invention relates to a nozzle assembly for co-extruding two liquids. Key features of the assembly provide significant technical advantages in controlling the formation of the liquid interfaces, through the design of both the inner and outer nozzles.

[0064] Unless otherwise defined, all terms used in disclosing the invention, including technical and scientific terms, have the meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. By means of further guidance, term definitions are included to better appreciate the teaching of the present invention.

[0065] As used herein, the following terms have the following meanings:

[0066] "A", "an", and "the" as used herein refers to both singular and plural referents unless the context clearly dictates otherwise. By way of example, "a compartment" refers to one or more than one compartment.

[0067] "Comprise", "comprising", and "comprises" and "comprised of" as used herein are synonymous with "include", "including", "includes" or "contain", "containing", "contains" and are inclusive or open-ended terms that specifies the presence of what follows e.g. component and do not exclude or preclude the presence of additional, non-recited components, features, element, members, steps, known in the art or disclosed therein.

[0068] Furthermore, the terms first, second, third and the like in the description and in the claims, are used for distinguishing between similar elements and not necessarily for describing a sequential or chronological order, unless specified. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that the embodiments of the invention described herein are capable of operation in other sequences than described or illustrated herein.

[0069] The recitation of numerical ranges by endpoints includes all numbers and fractions subsumed within that range, as well as the recited endpoints.

[0070] The expression "% by weight", "weight percent", "%wt" or "wt%", here and throughout the description unless otherwise defined, refers to the relative weight of the respective component based on the overall weight of the formulation.

[0071] Whereas the terms "one or more" or "at least one", such as one or more or at least one member(s) of a group of members, is clear per se, by means of further exemplification, the term encompasses inter alia a reference to any one of said members, or to any two or more of said members, such as, e.g., any >3, >4, >5, >6 or >7 etc. of said members, and up to all said members.

[0072] Unless otherwise defined, all terms used in disclosing the invention, including technical and scientific terms, have the meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. By means of further guidance, definitions for the terms used in the description are included to better appreciate the teaching of the present invention. The terms or definitions used herein are provided solely to aid in the understanding of the invention.

[0073] Reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment, but may. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner, as would be apparent to a person skilled in the art from this disclosure, in one or more embodiments. Furthermore, while some embodiments described herein include some but not other features included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the invention, and form different embodiments, as would be understood by those in the art. For example, in the following claims, any of the claimed embodiments can be used in any combination.

[0074] "Terminus" refers to the ending part or tip of a nozzle, where the extruded liquid exits.

[0075] "Circumference of Inner Nozzle" pertains to the perimeter of the cross-sectional shape of the inner nozzle's terminus.

[0076] "Circumference of Outer Nozzle" pertains to the perimeter of the cross-sectional shape of the outer nozzle jacket's terminus.

[0077] "Cross-sectional Shape" refers to the shape observed when cutting perpendicular to the length of the nozzle. The cross-sectional shape can generally be seen directly at the terminus of the nozzle.

[0078] "Curvature" denotes the measure of the roundedness of the edges of the nozzle's cross-sectional shape, terminus, typically defined by a mathematical function of the curve. "Thermal effusivity" is the square root of the product of a materials thermal conductivity and its volumetric heat capacity. It is a measure of a materials thermal inertia.

[0079] "Drip extrusion" or "deposition extrusion" is a manufacturing process used primarily in the production of certain food products and biopolymers. In this process, a liquid or semi-liquid material is extruded through a nozzle and deposited drop by drop onto a substrate, into a mold or into a solution where it solidifies or gels. In drip co-extrusion or deposition co-extrusion, two liquids are simultaneously extruded through a nozzle and deposited drop by drop onto a substrate, into a mold or into a solution.

[0080] In a first aspect, the invention relates to a nozzle assembly for co-extruding two liquids, the nozzle assembly comprising: an outer nozzle jacket having a first terminus; and an inner nozzle having a second terminus, wherein the inner nozzle is disposed within the outer nozzle jacket.

[0081] In a preferred embodiment, the invention relates to a nozzle assembly for drip co- extrusion or deposition co-extrusion. The adapted nozzle assembly is specifically designed to reduce common issues associated with drip co-extrusion of center filled goods such as candy tailing, interlinking, off-center filling which tend to lead to leakage.

[0082] In a second aspect, the invention relates to the inner nozzle for extruding the centerfill liquid.

[0083] In a third aspect, the invention relates to a process for co-extruding two liquids.

[0084] Structure of the Nozzle Assembly

[0085] A. Outer Nozzle Jacket

[0086] The outer nozzle jacket plays a critical role in forming the liquid-air interface, stabilizing forces, and maintaining a well-controlled liquid flow.

[0087] Terminus Design: The first terminus of the outer nozzle jacket may have a round circumference. This feature promotes a smooth and even flow of the outer liquid, aiding in the formation of the liquid-air interface. Shape Constancy: In a preferred embodiment, the last section of the outer nozzle maintains a constant shape for at least 1 cm from the terminus, allowing for unidirectional flow. This feature minimizes perturbing forces on the liquid interface, enhancing the stability of the extrusion process.

[0088] B. Inner Nozzle

[0089] The inner nozzle is central to the nozzle assembly, offering a variety of features that contribute to controlled flow and formation of liquid-liquid interface between inner and outer liquids, thus resulting in improved operational stability. This in turn results in better quality assurance of the obtained center-filled goods. Additionally, this provides the ability to produce center-filled goods with a larger ratio of center-fill liquid to shell matrix in a reliable manner.

[0090] In a preferred embodiment, the terminus of the inner nozzle extends further than the terminus of the outer nozzle. In a preferred embodiment, the terminus of the inner nozzle extends beyond the terminus of the outer nozzle. The applicant surprisingly found that extending the terminus of the inner nozzle beyond the terminus of the outer nozzle significantly improved the controlled production of center-filled goods through coextrusion. Without being bound by theory, it is believed that forming the air-liquid interface between the shell matrix and the air prior to forming the liquid-liquid interface between shell matrix and center-fill liquid improves control over the process.

[0091] The properties of both inner and outer nozzle which are disclosed herein are most important at and near the nozzle terminus, for example in the last 5 mm as measured from the nozzle terminus, more preferably in the last 1 cm as measured from the nozzle terminus, most preferably in the last 1.5 cm as measured from the nozzle terminus.

[0092] Material Composition: The inner nozzle is preferably comprised of materials with high thermal conductivity and / or thermal effusivity.

[0093] Suitable materials include metals such as stainless steel, aluminum, copper, and bronze. The most preferred material is steel, more preferably stainless steel, offering robust thermal properties and structural integrity. In a preferred embodiment, the inner nozzle has a thermal conductivity of at least 1 W I (m*K), more preferably at least 5 W / (m*K), more preferably at least 10 W / (m*K). In a preferred embodiment, the inner nozzle has a thermal effusivity of at least 1 kJ I (m2*K*s1 / 2), more preferably at least 5 kJ / (m2*K*s1 / 2), most preferably at least 10 kJ / (m2*K*s1 / 2).

[0094] The applicant found that small, local variations or fluctuations in temperature have a significant effect on the extrusion process, for example by impacting viscosity. These fluctuations were reduced by utilizing a nozzle with a high thermal effusivity, which allow the nozzle to better maintain its equilibrium temperature throughout the intermittent extrusion of inner and outer liquids.

[0095] In a further preferred embodiment, the inner nozzle has a high thermal conductivity, in combination with a thin inner nozzle thickness. In a further preferred embodiment, the inner nozzle has a thermal conductivity of at least 1 W / (m*K), more preferably at least 5 W / (m*K), more preferably at least 10 W / (m*K) and an inner nozzle thickness of at most 3 mm, more preferably at most 2 mm, more preferably at most 1.5 mm, more preferably at most 1.0 mm, more preferably at most 0.75 mm, more preferably at most 0.50 mm. This is particularly advantageous when the shell matrix melt and inner liquid are extruded at different temperatures. Insulating and I or thick inner nozzles result in quenching of the hotter fluid at the liquid-liquid interface upon extrusion. This destabilizes the flow. The nozzle design of present application reduces the quenching effect while minimizing temperature effects upstream of the nozzle terminus. This gives the operator more flexibility in determining the ideal extrusion temperature for the inner liquid and outer shell melt independently.

[0096] Surface Roughness: In a preferred embodiment, the inner nozzle has a surface roughness (Ra) measured as the arithmetic mean roughness alongside the length of the inner nozzle, and wherein the Ra value is at least 0.1 pm, more preferably at least 0.3 pm, more preferably at least 0.5 pm, more preferably at least 0.75 pm. In another embodiment, the inner nozzle has a surface roughness Ra between 0.5 and 1.5 pm, more preferably between 0.7 and 1 pm.

[0097] This roughness contributes to slowing down the flow along the surface, aiding in forming a stable and well-controlled liquid-liquid interface.

[0098] In a further preferred embodiment, the surface roughness is combined with an increased nozzle surface area relative to extrusion volume of the inner liquid. This is achieved by increasing the perimeter of the inner nozzle relative to the crosssectional area enclosed by said perimeter of said inner nozzle.

[0099] Cross-sectional Shape and Curvature: The cross-sectional shape of the inner nozzle's terminus is preferably characterized by continuous and smooth curves, devoid of sharp angles or vertices. This is advantageous as corners and edges both strongly impact the local flow characteristics and because viscous fluids may remain inside the corners. Preferably, the perimeter of the inner nozzle is maximized relative to the enclosed area. More preferably, the cross-sectional shape of the inner nozzle resembles a rounded multi-lobed figure, such as a rounded four-leaved clover or a similar configuration. By maximizing the perimeter relative to the enclosed area, a smoother transition between flow within the inner nozzle and free flowing liquids forming a liquid-liquid interface is obtained. Most preferably, the cross-sectional shape of the inner nozzle is a rounded, four-lobed shape.

[0100] In a preferred embodiment, the second terminus of the inner nozzle has a cross- sectional shape with a circumference-to-area ratio greater than that of a circle. Increasing the inner nozzle surface area relative to the extrusion volume, by increasing the inner nozzle's cross-sectional perimeter relative to the cross-sectional area enclosed by said perimeter, increases the friction of the nozzle's surface.

[0101] At or near a surface, fluid flow rate is decreased in what is known as a boundary layer or region. This boundary layer generally exhibits laminar flow patterns, which are significantly more predictable and devoid of eddies. This allows the nozzle to promote well-controlled laminar flow patterns particularly where the liquid-liquid interface will be formed. These effects are most pronounced on the center-fill liquid, but similar effects are noted at the inner perimeter of the annular passageway for the shell matrix. Additionally, these effects are described with respect to mass flow rates. However, similar considerations apply to convective thermal transfer. Laminar flow rates result in similar velocity as well as temperature boundary layer conditions.

[0102] That is to say, the inner nozzle surface creates conditions beneficial to the formation of the liquid-liquid interface. The flow rates are controlled and slower. Flow components, including eddies, that deviate from the axial direction are minimized. If both liquids are at a different temperature, the boundary layers formed at both sides of the inner nozzle exhibit a temperature profile which at the inner nozzle wall lies close to the contact temperature resulting of bringing both liquids into direct contact. These factors result in a very well controlled flow regime at both sides of the inner liquid nozzle, thereby promoting a controlled formation of the liquid-liquid interface.

[0103] The increased surface area of the inner nozzle prior to extrusion is rapidly reduced towards a minimal surface area upon formation of the liquid-liquid interface as a consequence of the liquids surface energy. This process is believed to dominate the formation of the liquid-liquid interface, acting as a damping force on other perturbations.

[0104] Preferably, corners are avoided. By having a rounded shape, similar boundary flow conditions can be obtained across the inner nozzle's surface. Corners and edges lead to specific boundary flow conditions which deviate from those found at flat or rounded edges. Additionally, capillary action is stronger within sharp edges, leading to liquid not being extruded or being extruded slowly. The applicant found inner nozzle shapes with corners were more likely to result in stringing of the center-filled goods upon extrusion.

[0105] In a more preferred embodiment, the second terminus of the inner nozzle has a rounded, multi-lobed cross-sectional shape, preferably a rounded four-lobed cross- sectional shape. In a more preferred embodiment, the second terminus of the inner nozzle has a cross-sectional shape of a rounded four-leaved clover. A rounded, four- lobed cross sectional shape resembling a rounded four-leaved clover can be seen in figures 4A and 4B. The applicant found an inner nozzle with this shape showed significantly better process control and quality assurance of center-filled goods compared to circular, oval, square, (not rounded) 4 and 5-pointed star-shapes and (not rounded) four-leaved clover shapes.

[0106] In a preferred embodiment, the last section of the inner nozzle maintains a constant shape for at least 1 cm from the terminus, allowing for unidirectional flow. This feature minimizes perturbing forces on the liquid interface, enhancing the stability of the extrusion process.

[0107] Effects of the nozzle assembly

[0108] A. Stable Interface Formation

[0109] The design of the nozzle assembly promotes that the liquid-air interface of the outer liquid forms before the liquid-liquid interface. This staged formation provides a stable outer interface, reducing perturbing forces during the formation of the inner interface. The constant shape of the annular passageway and the inner passageway near their respective nozzle terminus, the surface roughness of the inner nozzle, and the specific shape design all contribute to this stability.

[0110] B. Controlled Flow Dynamics

[0111] By increasing the surface roughness and adopting a unique cross-sectional shape, the assembly slows down the flow along the inner nozzle's surface. This control over the flow dynamics enables a well-regulated and consistent liquid-liquid interface. The use of materials with high thermal conductivity and capacity, such as steel, exhibits similar control over the temperature profile of both liquids; gradually bringing both liquids to their respective contact temperature rather than quenching, thereby further enhancing the control of the flow.

[0112] C. Minimized Perturbing Forces

[0113] The nozzle assembly design ensures unidirectional flow of both liquids, minimizing forces on the liquid-liquid interface. Unlike traditional coaxial nozzles with cone- shaped endings, this design avoids inward pressure on the inner liquid, reducing the risk of interface disturbances.

[0114] Process of co-extruding two liquids to form a center-filled good

[0115] In a third aspect, the invention relates to a process of co-extruding two liquids to form a center-filled good using a nozzle assembly as defined in claim 1, the method comprising: a) initiating extrusion of an outer shell liquid from the outer nozzle; b) initiating extrusion of an inner liquid from the inner nozzle having a second terminus that protrudes beyond the first terminus of the outer nozzle jacket, wherein the initiation of the inner liquid extrusion occurs shortly after the initiation of the outer shell liquid extrusion; c) stopping the extrusion of the inner liquid; and d) subsequently stopping the extrusion of the outer shell liquid, wherein the outer shell liquid fully encapsulates the inner liquid.

[0116] In a further preferred embodiment, the outer shell liquid is extruded at outer shell extrusion temperature Te, os; and wherein the inner liquid is extruded at inner liquid extrusion temperature Te, n, wherein the outer shell extrusion temperature Te, os and the inner liquid extrusion temperature Te, n differ by at least 5°C, preferably at least 20°C. More preferably, the outer shell extrusion temperature Te, os is at least 5°C higher than the inner liquid extrusion temperature Te, n, more preferably at least 10°C higher, more preferably at least 20°C higher, more preferably at least 30°C higher, more preferably at least 35°C higher, more preferably at least 4O°C higher, more preferably at least 50°C higher.

[0117] The nozzles disclosed in present application advantageously overcome some of the drawbacks to co-extruding liquids at different temperatures, particularly improving the quality assurance and stability of the obtained center-filled product. Consequently, the nozzles disclosed in present application allow larger variations in inner and outer liquid temperatures during the co-extrusion process. In turn, this gives formulators a wider range of options with respect to liquids and compounds to be included within those liquids to choose from.

[0118] Preferably the center-fill product is formed by encapsulation of the inner liquid within the outer shell by concentric extrusion - dripping techniques. In such methods, the outer shell flows from the outer concentric nozzle first, followed by inner liquid flow from the inner concentric nozzle while flow from outer shell concentric nozzle continues. The inner liquid flow is stopped, then subsequently the outer shell flow is stopped. This sequence of liquid flows may be accompanied by a nozzle movement. Each sequence of liquid flows produces a single drop, which upon cooling down forms a stable center-fill product according to the first aspect of the present invention. Advantageously, no contacting the outer shell into gelation or fixation mixtures, such as mixture comprising calcium ions, is required.

[0119] Preferably, the invention relates to a process of drip co-extrusion or deposition coextrusion. In such a process, each of the steps a), b), c) and d) are performed in a sequential order. This leads to the formation of an individual center-filled good which is deposited.

[0120] In a preferred embodiment, the process of drip co-extrusion further comprises the step of :

[0121] - deposition of a droplet onto a substrate, wherein said outer shell liquid encapsulates said inner liquid entirely.

[0122] In a more preferred embodiment, said substrate onto which said droplet is deposited is a mold. More preferably, said substrate onto which said droplet is deposited is both a mold and the final packaging. Advantageously, this eliminates demolding and packaging steps as well as possible issues with leakage during these steps. In a further more preferred embodiment, said substrate onto which said droplet is deposited is a plastic backing provided with a series of pre-formed pockets, each pre-formed pocket suitable for deposition and packaging of a single center-filled good. Most preferably, said substrate is a blister. A blister includes one or a series of pre-formed cavities or pockets made from a formable material, preferably a thermoformed plastic and a backing which can be made from various materials such as foils including metallic foils, polymers and paperboard.

[0123] In a preferred embodiment, the process of drip co-extrusion comprises the step of deposition of each center-filled good into a pre-formed pocket of a blister; and the subsequent provision of a backing material onto said blister thereby obtaining a blister with center-filled goods. This has a multitude of advantages. Each center- filled good is packaged in an individual container formed between the pre-formed pocket and the backing. This reduces the issues if leaking does occur. It also allows opening the blister for each individual center-filled good to be consumed immediately, thereby improving shelf life. As the blister acts as both mold and packaging, additional demolding and packaging steps are eliminated.

[0124] In an embodiment, the substate, in particular the blister, may be actively cooled during deposition. In a further embodiment, the blister may be cooled to a temperature between -30 and 0°C, more preferably a temperature between -25° and -10°C, most preferably about -15°C. Active cooling of the blister aids in protecting the material while speeding up the deposition and gellification of the outer shell. However, it comes at a high operational energy cost.

[0125] In a more preferred embodiment, the pre-formed pocket of said blister is made from a polymer, more preferably a thermoplastic polymer. This allows easy production and recycling of the blister. Further more preferably, said thermoplastic polymer has a softening point at ION as measured according to ISO 306:2022 of at least 120°C, more preferably at least 130°C, more preferably at least 140°C, more preferably at least 150°C. When the blister is used as both mold and packaging, it is important that said blister can withstand deposition of the hot droplet without shrinkage or deformation without resulting in non-uniform, deformed or faulty packaging. In a further preferred embodiment, the blister is not cooled during deposition. More preferably, the blister is maintained at room temperature during deposition. Most preferably, the blister has a temperature between 5 and 25°C during deposition of the droplet into the pre-formed pocket. Advantageously, with sufficiently high temperature resistance, active cooling to protect the blister material is not required resulting in much lower operational energy requirements and complexity. If sped up gelling of the center-filled liquid is desired, this can be more energy efficiently achieved by passing or storing the blister in a cooling cell subsequent to the drip coextrusion of the material.

[0126] Preferably, said thermoplastic polymer has tensile modulus measured according to ISO 527-2:2012 of at least 1000 MPa, more preferably at least 1200 MPa, more preferably at least 1400 MPa. Sufficiently high tensile strength is desirable to ensure sufficiently rigid packaging. Especially when the center-filled good comprises a genuine inner liquid with relatively low viscosity in a high amount, the center-filled good is easily deformed and can burst upon deformation. To avoid bursting, for example when in the pocket of a consumer, sufficiently high rigidity of the preformed pockets is desired.

[0127] Preferably, said thermoplastic polymer has a gas permeability to nitrogen N2as measured by DIN 53380 of at most 50 cm3.mm / m2.d.bar, more preferably at most 40 cm3.mm / m2.d.bar, more preferably at most 30 cm3.mm / (m2.d.bar).

[0128] Preferably, said thermoplastic polymer has a gas permeability to oxygen O2as measured by DIN 53380 at 23°C and 50% relative humidity of at most 250 cm3.mm / m2.d.bar, more preferably at most 220 cm3.mm / (m2.d.bar), more preferably at most 180 cm3.mm / m2.d.bar.

[0129] Preferably, said thermoplastic polymer has a gas permeability to water vapor H2O as measured by DIN 53380 at 38°C and 90% relative humidity of at most 1.0 g.mm / (m2.d), more preferably at most 0.8 g.mm / (m2.d) , more preferably at most 0.7 g.mm / (m2.d) , more preferably at most 0.6 g.mm / (m2.d) , more preferably at most 0.5 g.mm / (m2.d) , more preferably at most 0.4 g.mm / (m2.d) , more preferably at most 0.3 g.mm / (m2.d).

[0130] In a preferred embodiment, said thermoplastic polymer is translucent. More preferably, said thermoplastic material is clear. This advantageously allows inspection of the center-filled goods during and after closing the blister with its backing. This is desirable to avoid faulty products such as blisters containing leaking center-filled goods. It is also desired by consumers as the ability to inspect the products in a packaged state improves consumer confidence in the product.

[0131] A low gas permeability is desired to ensure sufficient shelf life of the center-filled goods. This is particularly desired to avoid oxidation, discoloration, drying out and hardening of the soft gummies. In a preferred embodiment, the pre-formed pocket of said blister is made from a thermoplastic polymer and has a thickness of at least 200 pm, more preferably at least 250 pm. In a preferred embodiment, the pre-formed pocket of said blister is made from a thermoplastic polymer and has a thickness of at most 600 pm, more preferably at most 400 pm, more preferably at most 350 pm. It was found that a blister formed according to the preferred embodiment resulted in a blister which would withstand deposition of the hot droplet into it and result in a high quality packaging with minimal material requirements; without the need for cooling.

[0132] In the most preferred embodiment, the thermoplastic polymer is selected from: polyethylene terephthalate (PET), polypropylene (PP), polycarbonate (PC), polyvinyl chloride (PVC), more preferably PET and PP, most preferably PP. These polymers are capable of achieving the desirable properties as outlined above. PP and PET are more preferred as PVC requires significant amounts of additives for processability and achieving necessary properties, while still being less temperature resistant. PET and PP are superior at providing a gas barrier compared to PC. In addition, PC is more difficult to process into a pre-formed blister.

[0133] Outer liquid or shell matrix melt

[0134] In a preferred embodiment, the outer shell liquid is extruded at an elevated temperature. Preferably, the shell matrix melt is maintained at an elevated temperature in the shell matrix hopper. In a preferred embodiment, the outer shell liquid is extruded at a temperature of at least 30°C, more preferably at least 40°C, more preferably at least 50°C, more preferably at least 60°C, more preferably at least 70°C, more preferably at least 75°C, more preferably at least 80°C. In a preferred embodiment, the outer shell liquid is extruded at a temperature between 50 °C and 100°C, more preferably between 50 °C and 95 °C, more preferably between 60 °C and 95 °C, more preferably between 75 °C and 95 °C; most preferably between 85 and 95°C. Extruding the outer shell liquid at an elevated temperature significantly decreases its viscosity. This is particularly desirable to reduce stringing of the outer shell liquid upon extrusion. The outer liquid is generally more viscous, which makes this measure particularly interesting for a shell matrix. The high viscosity of the shell matrix results from its need to form a shell matrix upon cooling and I or contacting with gelation or crosslinking compounds. Preferably, the shell matrix melt forms a stable shell by cooling. In a preferred embodiment, the inner liquid is extruded at a lower temperature than the outer shell liquid. Preferably, the inner liquid is maintained at a temperature close to room temperature in the inner liquid hopper. In a preferred embodiment, the center filled good is filled with an inner liquid. As the inner liquid is sufficiently liquid at room temperature, heating is not required and maintaining the inner liquid at room temperature reduces energy requirements of the process. In addition, maintaining the inner liquid at a substantially lower temperature improves the process stability. Without being bound by theory, it is believed to be attributable to the more similar viscosities of inner and outer liquids during drip co-extrusion as well as quenching effect of the cool inner liquid on the hot outer liquid, accelerating gel formation of the outer shell.

[0135] In an preferred embodiment, said outer shell comprises 0.5-25 wt.% of a pectin relative to the weight of the outer shell. In an embodiment, said pectin is chosen from the group of : high methoxyl (HM) pectin, low methoxyl (LM) pectin or low methoxyl amidated (LMA) pectin.

[0136] In an embodiment, said outer shell further comprises a dicarboxylic acid or a tricarboxylic acid. The dicarboxylic acid or tricarboxylic acid improved the gel formation and resulted in a stronger and more elastic outer shell. In an embodiment, said outer shell further comprises a dicarboxylic acid, preferably a linear saturated dicarboxylic acid, more preferably Oxalic acid, Malonic acid, Succinic acid, Glutaric acid, pyruvic acid or Adipic acid. In an embodiment, said outer shell further comprises a dicarboxylic acid, preferably an unsaturated dicarboxylic acid, more preferably Maleic acid, Fumaric acid, Glutaconic acid, Traumatic acid or Citraconic acid. In an embodiment, said outer shell further comprises a dicarboxylic acid, preferably a substituted dicarboxylic acid, more preferably Tartronic acid, Mesoxalic acid, Malic acid, Tartaric acid or Glutamic acid. In an embodiment, said outer shell further comprises a tricarboxylic acid, preferably Citric acid, Isocitric acid, Aconitric acid or Agaric acid. In a particular preferred embodiment, said outer shell comprises tartaric or pyruvic acid, most preferably pyruvic acid. It was surprisingly found that these carboxylic acids had the greatest effect on gel strength, without compromising health and taste requirements. In a preferred embodiment, said outer shell comprises a dicarboxylic acid or tricarboxylic acid in an amount of at least 0.05 wt.% relative to the weight of the outer shell, more preferably in an amount of at least 0.1 wt.% relative to the weight of the outer shell, more preferably in an amount of at least 0.3 wt.% relative to the weight of the outer shell, more preferably in an amount of at least 0.5 wt.% relative to the weight of the outer shell, more preferably in an amount of at least 0.8 wt.% relative to the weight of the outer shell, more preferably in an amount of at least 1.0 wt.% relative to the weight of the outer shell.

[0137] In a preferred embodiment, said outer shell has a viscosity of 25-1000 Pa s measured at 20°C.

[0138] Inner liquid or center-fill liquid

[0139] In a preferred embodiment, said inner liquid has a moisture content of 5-99 wt.% as measured by ISO 760: 1978. In a preferred embodiment, the inner liquid has a viscosity of 0.01-20 Pa s measured at 20°C.

[0140] In a preferred embodiment, the inner liquid has a viscosity of 0.01-20 Pa s (Pa.s) measured at 20°C. Because the inner liquid has a viscosity of at most 20 Pa s measured at 20°C, the inner liquid is suitable to burst out of the outer shell when the outer shell ruptures.

[0141] The inner liquid has a sufficiently lower viscosity to provide a burst effect. When the center-fill product bursts, a liquid syrup is noticeably spread across the oral cavity and later down the throat. This further ameliorates the swift formation of soothing layer over the pharynx, providing immediate relief. In a preferred embodiment, the inner liquid has a viscosity of at most 18 Pa s measured at 20°C, more preferably a viscosity of at most 15 Pa s measured at 20°C, more preferably a viscosity of at most 10 Pa s measured at 20°C, more preferably a viscosity of at most 8 Pa s measured at 20°C, more preferably a viscosity of at most 6 Pa s measured at 20°C, more preferably a viscosity of at most 5 Pa s measured at 20°C. Viscosity is preferably measured according to ISO2555. In an embodiment, the viscosity of the inner liquid measured at 20°C is between 0.1 and 15.0 Pa s, preferably between 0.5 and 10.0 Pa s and more preferably between 1.0 and 10.0 Pa s.

[0142] In an embodiment, said inner liquid has a moisture content of at least 10 wt.% relative to the weight of the inner liquid, as measured by ISO 760: 1978. Because the outer shell comprises a combination of pectin and a hydrolysable tannin, the outer shell is suitable to encapsulate an inner liquid with a moisture content greater than 10 wt.%, as measured by ISO 760: 1978, for a prolonged period. Other materials, such as gelatin, can also form an outer shell but gelatin outer shells would not be suitable to encapsulate a liquid with such moisture content for longer periods of time. The water would migrate and can hydrolyze the outer shell. In a preferred embodiment, the inner liquid has a moisture content of at least 11 wt.% relative to the weight of the inner liquid as measured by ISO 760: 1978, more preferably a moisture content of at least 12 wt.% relative to the weight of the inner liquid as measured by ISO 760: 1978, more preferably a moisture content of at least 13 wt.% relative to the weight of the inner liquid as measured by ISO 760: 1978, more preferably a moisture content of at least 14 wt.% relative to the weight of the inner liquid as measured by ISO 760: 1978, more preferably a moisture content of at least 15 wt.% relative to the weight of the inner liquid as measured by ISO 760: 1978, more preferably a moisture content of at least 16 wt.% relative to the weight of the inner liquid as measured by ISO 760: 1978. In another preferred embodiment, the moisture content is at most 30 wt.% relative to the weight of the inner liquid as measured by ISO 760: 1978, more preferably the moisture content is at most 25 wt.% relative to the weight of the inner liquid as measured by ISO 760: 1978, most preferably the moisture content is at most 20 wt.% relative to the weight of the inner liquid as measured by ISO 760: 1978.

[0143] In a preferred embodiment, the inner liquid has a viscosity of at most 50 Pa s (Pa.s) measured at 20°C. Because the inner liquid has a viscosity of at most 50 Pa s measured at 20°C, the inner liquid is suitable to burst out of the outer shell when the outer shell ruptures. The inner liquid has a sufficiently lower viscosity to provide a burst effect. When the center-fill product bursts, a liquid syrup is noticeably spread across the oral cavity and later down the throat. This further ameliorates the swift formation of soothing layer over the pharynx, providing immediate relief. In a preferred embodiment, the inner liquid has a viscosity of at most 25 Pa s measured at 20°C, more preferably a viscosity of at most 20 Pa s measured at 20°C, more preferably a viscosity of at most 10 Pa s measured at 20°C, more preferably a viscosity of at most 8 Pa s measured at 20°C, more preferably a viscosity of at most 6 Pa s measured at 20°C, more preferably a viscosity of at most 5 Pa s measured at 20°C. Viscosity is preferably measured according to ISO2555. In an embodiment, the viscosity of the inner liquid measured at 20°C is between 0.1 and 50.0 Pa s, preferably between 0.5 and 25.0 Pa s and more preferably between 1.0 and 10.0 Pa s.

[0144] In an embodiment, the center fill liquid may be extruded at any desirable temperature, irrespective of the extrusion temperature of the shell matrix melt. In a preferred embodiment, the center fill liquid may be extruded at a substantially lower temperature than the shell matrix melt. This allows the inclusion of inner liquid components or compounds which cannot withstand high temperatures. This is particularly interesting when the center-filled good aims to deliver pharmaceutical compounds, many of which do not withstand high temperatures.

[0145] In a preferred embodiment, the center-fill product comprises the inner liquid in an amount of at least 0.1 g, more preferably at least 0.2 g, more preferably at least 0.3 g, more preferably at least 0.4 g, more preferably at least 0.5 g, more preferably at least 0.6 g, more preferably at least 0.7 g, more preferably at least 0.8 g, more preferably at least 0.9 g, more preferably at least 1.1 g, more preferably at least 1.2 g, more preferably at least 1.3 g, more preferably at least 1.4 g, more preferably at least 1.5 g, more preferably at least 1.6 g, more preferably at least 1.7 g, more preferably at least 1.8 g, more preferably at least 1.9 g, more preferably at least 2.0 g-

[0146] In a preferred embodiment, the center-fill product comprises the outer shell matrix in an amount of at least 2.0g, more preferably at least 2.5g, more preferably at least 2.8g, more preferably at least 3.0g, more preferably at least 3.1g, more preferably at least 3.2g, more preferably at least 3.3g.

[0147] In a preferred embodiment, the center-fill product comprises the outer shell matrix in an amount of at most 5.0g, more preferably in an amount of at most 4.5g, more preferably in an amount of at most 4.0g, more preferably in an amount of at most 3.5g.

[0148] One advantage of the present invention is the ability to store and deliver to the oral cavity a relatively large amount of liquid with a relatively high moisture content compared to the prior art. This is required to provide sufficient syrup to the oral cavity to obtain the benefits from the mechanical action of syrup, as well as allowing higher doses to be delivered in general.

[0149] In an embodiment, said outer shell and / or said inner liquid comprises a hydrolysable tannin or source of hydrolysable tannin, wherein said hydrolysable tannin is present in an amount of 0.2-20 wt.% relative to the weight of the center-fill product, preferably 0.3-10 wt.%. In an embodiment, said outer shell comprises a hydrolysable tannin or source of hydrolysable tannin, wherein said hydrolysable tannin is present in an amount of 0.2-20 wt.% relative to the weight of the centerfill product, preferably 0.3-10 wt.%. In an embodiment, said inner liquid comprises a hydrolysable tannin or source of hydrolysable tannin, wherein said hydrolysable tannin is present in an amount of 0.2-20 wt.% relative to the weight of the centerfill product, preferably 0.3-10 wt.%. Center-fill good or center-fill gummy

[0150] In a preferred embodiment, the center-fill product delivers a pharmaceutically active center-fill to a patient in need thereof. More preferably, the center-fill product has a syrup as center-fill. Solid, stable and convenient center-fill products may be used as carriers for an amount of syrup. This advantageously provides both advantages of solid oral dosages, such as high control over the dosage regime of the patient and convenience of use, as well as syrups such as a mechanical component to the method of action, immediate relief and quick dispersion of the API within the syrup.

[0151] In a preferred embodiment, the center-fill product comprises the inner liquid in an amount of at least 5 wt.% relative to the weight of the center-fill product, more preferably in an amount of at least 10 wt.% relative to the weight of the center-fill product, more preferably in an amount of at least 15 wt.% relative to the weight of the center-fill product, more preferably in an amount of at least 20 wt.% relative to the weight of the center-fill product, more preferably in an amount of at least 25 wt.% relative to the weight of the center-fill product, more preferably in an amount of at least 30 wt.% relative to the weight of the center-fill product, more preferably in an amount of at least 35 wt.% relative to the weight of the center-fill product, more preferably in an amount of at least 40 wt.% relative to the weight of the centerfill product, more preferably in an amount of at least 45 wt.% relative to the weight of the center-fill product, more preferably in an amount of at least 50 wt.% relative to the weight of the center-fill product, more preferably in an amount of at least 55 wt.% relative to the weight of the center-fill product, more preferably in an amount of at least 60 wt.% relative to the weight of the center-fill product, more preferably in an amount of at least 65 wt.% relative to the weight of the center-fill product, more preferably in an amount of at least 70 wt.% relative to the weight of the centerfill product. Higher amounts of inner liquid are desirable, when both mechanical as well as pharmaceutical methods of action are desired.

[0152] In more preferred embodiment, the center-fill product comprises the inner liquid in an amount of 20 to 50 wt.% relative to the weight of the center-fill product, more preferably in an amount of 20 to 40 wt.%, more preferably 20 to 35 wt.%, more preferably 25 to 35 wt.%, more preferably 25 to 30 wt.%, all relative to the total weight of the center-fill product. The inventors found these ratios lead to a sufficiently high liquid fill while simultaneously being able to eliminate leaking center- filled gummy. In a preferred embodiment, each gummy has a total weight of at least 1g, more preferably at least 2g, more preferably at least 3g, more preferably at least 4g. In a preferred embodiment, each gummy has a total weight of at most 10g, more preferably at most 8g, more preferably at most 6g, more preferably at most 5g. These weights allow for a high inner liquid to volume ratio and sufficient inner liquid to experience a clear burst effect upon the burst of the outer shell when the gummy is held in the mouth until bursting.

[0153] For a mechanical method of action generally a higher amount of liquid is required. To ensure the center-fill product remains manageable in size and weight, higher relative amounts of inner liquid are thus desirable or necessary. The trade-off for high amounts of inner liquid is a lower long-term stability and more difficulty with quality assurance. Reducing the amount of outer shell material in particular leads to higher chances of the soft gummy bursting, breaking, or leaking prematurely. When the inner liquid is a syrup, this results in a sticky, difficult to clean and very unpleasant mess. A single soft gummy bursting in a jar, pocket or any other type of bulk packaging can easily ruin the contents of all other items therein. It is thus of high importance that sufficient strength as well as long term stability is ensured. By consequence, commercial products are typically over dimensioned when compared to laboratory counterparts. Where on laboratory scale producing gels comprising with a high amount of inner liquid is doable, producing such soft gummies in bulk while ensuring long term stability and no premature leakage occurs is far more difficult.

[0154] Advantageously, the nozzle assembly of present invention allows the production of center-fill goods with high amounts of center fill relative to shell material reliably. The nozzle assembly of present disclosure helps ensure the center-fill is centered within the center-fill product. This diminishes the chances for uneven center-fill, thin shell matrix portions and stringing issues. Consequently, present application allows center-fill products with a high amount of inner liquid or center fill to be produced reliably.

[0155] The invention is further described by the following non-limiting examples which further illustrate the invention, and are not intended to, nor should they be interpreted to, limit the scope of the invention. DESCRIPTION OF FIGURES

[0156] Figure 1 shows a schematic representation of a continuous production process of center-filled goods through co-extrusion which may be employed.

[0157] The production process consists of at least two hoppers (20, 21), for the outer shell matrix melt (20) and one for the center-fill liquid (21), wherein each hopper is controlled by a plunger (24, 25) and fluidly connected to the manifold (28). Both fluid flows are redirected within the manifold to the nozzle assembly, from which the fluids are co-extruded.

[0158] The shell matrix melt 22 may be supplied to the outer nozzle 3 from a shell matrix hopper 20. The outer nozzle 3 may also be in flow communication with a shell matrix plunger 24 which moves between a first and a second position to deposit the shell component 22. The manifold 26 may comprise a shell matrix melt passageway 27 which fluidly connects the shell matrix hopper 22 to the outer nozzle 3, particularly the annular passageway 5.

[0159] The center or filler component 23 may be supplied to the inner nozzle 2 from a filler component hopper 21. The inner nozzle 2 may also be in flow communication with a center fill plunger 25, which moves between a first and a second position to deposit the center-fill liquid or inner liquid 23. The shell matrix 22 and the center-fill liquid 23 are coextruded in a mold 28 having mold cavities or impressions. Shell matrix melt 22 is supplied at a temperature above its melting point in shell matrix hopper 20.

[0160] Figure 2 displays a nozzle assembly from the prior art. This nozzle assembly is disclosed in US4229484. The nozzle assembly of figure 2 is a comparative example.

[0161] Figure 3A shows the desired center-filled product 30. As shown in figure 3A, the center-fill 32 is entirely encapsulated by shell matrix 31, with substantially even sidewalls, with the center-fill centered substantially centered within the shell matrix and absent of uneven side-walls, absent of thin portions and absent of stringing.

[0162] Figure 3B shows an embodiment of an undesirable center-filled product 33. As can be seen in figure 3B, the center-fill 32 is not centered within shell matrix 31 but instead close to its bottom wall. As a consequence, the side-walls are substantially uneven and the shell matrix displays thin portions. This type of deformation is often the result of phase-dropping, a problem common when coextruding liquids with nozzles of the prior art, particularly when the outer liquid has a low viscosity and I or when the inner liquid has a high density.

[0163] Figure 3C shows an embodiment of an undesirable center-filled product 33. As can be seen in figure 3C, the center-fill 32 is not centered within shell matrix 31. In addition, the center-filled product 33 shows evidence of stringing. This is evident from the string-like protrusion of the shell matrix 34 and the string-like protrusion of the inner liquid 35. Stringing occurs when either or both of the extrusion liquids are not expelled from their respectively nozzles sufficiently quickly. As a result, a protrusion often resembling a string of extrusion liquid that is late to exit the respective nozzle is found attached to the product. Removing the string often results in piercing the shell-matrix and leaking of the center-filled fluid therefrom. Stringing becomes more likely and problematic when extruding more viscous liquids.

[0164] Figure 4A shows a schematic representation of a preferred embodiment of an inner nozzle body according to present invention. Figure 4A shows an inner nozzle body 12. One end of the inner nozzle body 12 consists of the inner nozzle 2, with at its end the inner nozzle terminus 6. The other end is suited to be attached to either a flow distribution body 11 or the manifold 26. The inner nozzle body is hollow, forming an inner passageway 4, suitable fluidly communicate the inner fluid towards the inner nozzle terminus 6.

[0165] Preferably, the inner nozzle body 12 can be partially inserted into the flow distribution body 11 and fixed in place by connecting screws 15 which fit alongside inner nozzle body receivers 13. The inner nozzle body is provided with recess 14. This recess improves the ease of manufacturing and the ease of assembling the inner nozzle body 12 and the flow distribution body 11; by ensuring the inner body receivers 13 are aligned with the connecting screw holes 16 in the flow distribution body 11.

[0166] Figure 4B shows a cross-section of a preferred embodiment of an inner nozzle according to present invention. As can be seen on figure 4B, the inner nozzle has a rounded four-lobed shape at the side of the nozzle terminus 6. This rounded four- lobed shape increases the perimeter of the inner nozzle at the terminus relative to the cross sectional area within its perimeter. The inner nozzle has a constant wall thickness, and thus a similar shape on its outer and its inner perimeter. The wall thickness 17 of the inner nozzle is 0.35 mm. The inner nozzle is made of stainless steel with a surface roughness Ra of at least 0.8 |jm.

[0167] Figure 5 shows a schematic representation of a preferred embodiment of an outer nozzle according to present invention. Figure 5 shows an embodiment of a nozzle jacket 8, comprising an outer nozzle 3 which has an outer nozzle terminus 7. In a preferred embodiment, the nozzle jacket 8 is attached to the manifold 26. The flow distribution body 6 and inner nozzle body 12 are assembled and placed within the manifold 26. In accordance with the present invention, the inner nozzle terminus 6 then protrudes from, that is to say extends beyond, the terminus of the outer nozzle 7.

[0168] Figure 6 shows a schematic representation of an embodiment of a flow distribution body according to present invention. Figure 5 shows an embodiment of a flow distribution body 11 in accordance with present invention. The flow distribution body 11 contains, along its outside, a series of flow distributing protrusions 9 and 9', and in between said protrusions a series of flow distributing apertures 10 and 10'.

[0169] Figure 7 shows an exploded representation of a preferred embodiment of the nozzle assembly according to present invention. Figure 7 shows the inner nozzle body 12, which is partially inserted into flow distribution body 11, until the inner nozzle body receiver 13 align with the connecting screw holes 16, through which both parts are fixated to one another. The assembled inner nozzle body and flow distribution body are then to be inserted into the manifold 26. The nozzle jacket 8 is attached to the other end of manifold 26, so that the inner nozzle terminus 6 extends beyond the outer nozzle terminus 7.

[0170] When the flow distribution body 11 is placed within the manifold 26 and the nozzle jacket 8, an annular passageway 5 is formed in the space between the flow distributing body 11 and the manifold 26 and nozzle jacket 8 which fluidly connects the shell matrix melt passageway 27 until it is extruded between the outer nozzle terminus 3 and the inner nozzle terminus 2. This can be clearly seen on figure 8A.

[0171] The flow distributing apertures 10 and 10' located on the flow distribution body 11 at least substantially evenly distribute the shell component 22 within the annular passageway 5 before the shell matrix 22 contacts and partially enrobes the centerfill liquid 23 which is fed through the inner passageway 4 of the inner nozzle 2. This is further improved by providing two sets of flow distributing protrusions 9 and 9' and flow distributing apertures 10 and 10', wherein flow distributing protrusions 9' and flow distributing apertures 10' are downstream along the flow direction of the annular passageway from flow distributing protrusions 9 and flow distributing apertures 10. At two of the lower flow distributing apertures 10', two connecting screw holes 16 are provided to fixate the inner nozzle body to the flow distributing body. The connecting screw 16 are sealed after fixation, the connecting screw holes 16 should not allow any fluid passage from the annular passageway 5 to the inner passageway 4.

[0172] Figure 8A shows a schematic cross section of preferred embodiment of the nozzle assembly according to present invention.

[0173] Figure 8B shows a detailed representation of the schematic cross section of the nozzles of figure 8A.

[0174] The nozzle assembly 1 has an inner nozzle 2 which conveys a center or filler component 23 through an inner passageway 4. The inner nozzle 2 is located within an outer nozzle 3 which creates an annular passageway 5 for conveyance of a shell component 22.

[0175] As can be seen in figures 8A and 8B, the annular passageway 5 is formed between nozzle jacket 8 and flow distribution body 11 and inner nozzle body 12. These are fixated to one another through screws 15 within inner nozzle body receiver 13. The annular passageway is partially blocked by flow distributing protrusions 9 and 9', which forces the shell matrix melt 22 to flow through the flow distributing apertures 10 and 10'. These help ensure a proper distribution of the shell matrix melt, in particular to remove the lateral flow component derived from introducing the shell matrix melt 22 laterally from the shell matrix melt passageway 27. Similar measures are not required for the center-fill liquid, as the center-fill liquid is extruded co-axially from center-fill hopper 21, through inner passageway 4 towards the inner nozzle.

[0176] The shell matrix melt 22 flows through the annular passageway 5 and is extruded from the space between the outer nozzle terminus 7 and the inner nozzle terminus 6. The center-fill fluid 23 flows through the inner passageway 4 and is extruded from the inner nozzle terminus 6.

[0177] The inner nozzle terminus 6 extends beyond the outer nozzle terminus 7. The annular passageway 5 and the inner passageway 4 are substantially unidirectional for over 1 cm prior to their respective terminus. This promotes a unidirectional fluid flow which does not comprise any flow components which can destabilize the liquidliquid interface formed at the inner nozzle terminus.

[0178] The present invention is in no way limited to the embodiments described in the examples and / or shown in the figures. On the contrary, methods according to the present invention may be realized in many different ways without departing from the scope of the invention.

Claims

CLAIMS1. Nozzle assembly for drip co-extruding two liquids at a high temperature, the nozzle assembly comprising:- an outer nozzle jacket having a first terminus; and- an inner nozzle having a second terminus, wherein the inner nozzle is disposed within the outer nozzle jacket, characterized in that the second terminus of the inner nozzle extends further than the first terminus of the outer nozzle jacket.

2. Nozzle assembly of claim 1, wherein the second terminus of the inner nozzle has a cross-sectional shape with a circumference-to-area ratio greater than that of a circle.

3. Nozzle assembly according to any of claims 1-2, wherein the second terminus of the inner nozzle does not have corners.

4. Nozzle assembly according to any of claims 1-3, wherein the second terminus of the inner nozzle has a rounded, multi-lobed cross-sectional shape, preferably a rounded four-lobed cross-sectional shape.

5. Nozzle assembly according to any of claims 1-4, wherein the second terminus of the inner nozzle has a cross-sectional shape of a rounded four-leaved clover.

6. Nozzle assembly according to any of claims 1-4, wherein the inner nozzle has a thermal conductivity of at least 1 W / (m*K), preferably at least 10 W / (m*K).

7. Nozzle assembly according to any of claims 1-5, wherein the inner nozzle has a thermal effusivity of at least 1 kJ / (m2*K*s1 / 2), preferably at least 10 kJ I (m2*K*s1 / 2).

8. Nozzle assembly according to any of claims 1-6, wherein the inner nozzle has a surface roughness (Ra) measured as the arithmetic mean roughness alongside the length of the inner nozzle, and wherein the Ra value is at least 0.1 pm, preferably at least 0.5 pm.

9. Nozzle assembly according to any of claims 1, wherein the first terminus of the outer nozzle jacket has a round circumference.

10. Nozzle assembly according to any of claims 1, wherein both the inner nozzle and the outer nozzle jacket have a constant cross-sectional shape for a length of at least 1 cm prior to their respective terminus.

11. Inner nozzle for extrusion of a center-fill liquid, said inner nozzle having a terminus, wherein said the terminus of the inner nozzle has a cross- sectional shape with a circumference-to-area ratio greater than that of a circle.

12. Inner nozzle according to claim 1, wherein the terminus of the inner nozzle has a rounded, multi-lobed cross-sectional shape, preferably a rounded four-lobed cross-sectional shape.

13. Method of drip co-extruding two liquids to form a center-filled good using a nozzle assembly as defined in claim 1, the method comprising: a) initiating extrusion of an outer shell liquid from the outer nozzle; b) initiating extrusion of an inner liquid from the inner nozzle having a second terminus that protrudes beyond the first terminus of the outer nozzle jacket, wherein the initiation of the inner liquid extrusion occurs shortly after the initiation of the outer shell liquid extrusion; c) stopping the extrusion of the inner liquid; and d) subsequently stopping the extrusion of the outer shell liquid, wherein the outer shell liquid fully encapsulates the inner liquid.

14. Method of co-extruding two liquids according to claim 13, wherein the outer shell liquid is extruded at outer shell extrusion temperature Te, os; and wherein the inner liquid is extruded at inner liquid extrusion temperature Te, n, wherein the outer shell extrusion temperature Te, os and the inner liquid extrusion temperature Te, n differ by at least 5°C, preferably at least 20°C.

15. Method according to claim 13, wherein the outer shell extrusion temperature Te, os is at least 30°C higher than the inner liquid extrusion temperature Te, n.

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