Compact system for packaging microfibrillated cellulose

Abstract

The present invention relates to a system for compact packaging of microfibrillated cellulose, the system comprising a package comprising at least one polymeric material. The package contains a content consisting essentially of microfibrillated cellulose ("MFC") present as a suspension in a solvent. The resulting system has an essentially round or essentially rectangular or oval outer periphery, as defined by the dimensions of the package when completely filled with the content. The system of the present invention is particularly advantageous for providing a rigid, strong, essentially round package shape. The resulting packaged MFC units can be easily stacked on a pallet. The package maintains the water-holding capacity of the suspension (paste). The present invention also relates to a process for manufacturing such a system. [Selected figure] Figure 3

Description

Technical Field

[0001] The present invention relates to a system for the compact packaging of microfibrillated cellulose.

[0002] Microfibrillated cellulose is typically commercialized as a paste-like suspension that cannot be easily emptied from a container. The system of the present invention includes a package containing at least one polymeric material. The package contains a content consisting essentially of microfibrillated cellulose ("MFC") present as a suspension in a solvent. The microfibrillated cellulose has a solids content (i.e., the weight of MFC relative to the total weight, i.e., "w / w"% ) in the solvent of 2% dry matter to 50% dry matter, preferably 3% to 30%, more preferably 5% to 12%. The resulting system has an outer perimeter that is essentially round, essentially rectangular, or oval when defined by the dimensions of the package when completely filled with the content.

[0003] The system of the present invention has the advantage, inter alia, of providing a rigid and strong package shape that is essentially round or essentially rectangular or oval. The resulting packaged MFC units can be easily stacked on a pallet. The package maintains the water retention capacity of the suspension (paste).

[0004] The present invention also relates to a manufacturing process for such a system.

Background Art

[0005] Microfibrillated cellulose (also known as "network" cellulose or "ultrafine" cellulose, or especially as "cellulose nanofibril", hereinafter also referred to as "MFC") is a cellulose-based product and is described, for example, in Patent Document 1, Patent Document 2, and Patent Document 3. According to Patent Document 2, microfibrillated cellulose has a reduced length scale (diameter, fiber length) with respect to cellulose, improved water retention, and adjustable viscoelastic properties. MFC having further improved properties and / or properties adapted for specific applications is known, in particular, from Patent Document 4 and Patent Document 5.

[0006] Microfibrillated cellulose ready for transportation to the customer after production is typically present as a "paste", i.e., as a suspension in a solvent of solid microfibrillated fibers, typically in water. Dehydrated microfibrillated cellulose having a typical dry content (solid content) of 8 to 15% has handling problems. This paste (suspension) is neither a liquid nor a solid but a paste and has non-Newtonian fluid properties (see FIG. 1 for a photograph of non-incorporated microfibrillated cellulose dehydrated to a solid content of 8 to 12%).

[0007] Patent Document 6 discloses a conditioning process for microfibrillated cellulose that allows it to be more easily transported in a dry form and then re-wetted and defibrated at a different location. Patent Document 7 discloses that the pulp obtained after refining can be further dehydrated, for example, for transportation and then diluted to a suitable consistency before use.

[0008] Conventional packages such as plastic bags, buckets, or drums have been found not to be ideal for containing large volumes / large amounts of microfibrillated cellulose. Microfibrillated cellulose can be filled into various types of containers, but it is relatively difficult and resource-intensive to empty containers such as bottles, bags, or cans, which are typically used for solid or liquid transportation.

[0009] The MFC may, in principle, be filled in a plastic bag, which is relatively easy to empty, but this bag cannot be stacked typically due to the "air pockets" formed in this bag. The presence of such air pockets causes problems when trying to stack the filled bags on a pallet. Especially during storage and transportation, these bags will take various shapes, making transportation difficult if not impossible.

Prior Art Documents

Patent Documents

[0010]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Patent Document 7

Summary of the Invention

Problems to be Solved by the Invention

[0011] Based on the above, the present invention aims to provide a compact package specifically for microfibrillated cellulose existing as a "paste", which avoids or minimizes any or all of the drawbacks outlined above.

Means for Solving the Problems

[0012] The inventors have surprisingly found that a microfibrillated cellulose (MFC) suspension having a dry matter (solid) content of 2% by weight / weight ("w / w") to 50 w / w%, preferably 3 w / w% to 30 w / w%, more preferably 5 w / w% to 12 w / w% can be packaged in a manner such that the performance characteristics of the microfibrillated cellulose do not (significantly) deteriorate, as might be the case in conventional packaging, for example, simple filling into a plastic sack.

[0013] According to a first aspect of the present invention, the above problems and the like are solved by a system including the following: · At least one package containing at least one polymer material; · Contents of the package completely enclosed by the package, the contents consisting essentially of microfibrillated cellulose present in at least one solvent; The microfibrillated cellulose and the solvent form a suspension of the microfibrillated cellulose in the solvent, The solid content of the microfibrillated cellulose relative to the total weight of the suspension is 2% by weight / weight ("w / w") to 50 w / w%, preferably 3 w / w% to 30 w / w%, more preferably 5 w / w% to 12 w / w%, and the package, when filled entirely with the contents, is essentially round or essentially rectangular or oval, defining the outer perimeter of the overall system, i.e., the packaged microfibrillated cellulose, The length of the system is 1.5 times or more, preferably 3 times or more, more preferably 4 times or more the maximum width defining the cross-section of the outer perimeter (which is essentially round, oval, or rectangular).

[0014] According to the present invention, the term "suspension" is understood generally by those skilled in the art and as described in the IUPAC "Gold Book", [PAC, 1972, 31, 577 (Manual of Symbols and Terminology for Physicochemical Quantities and Units, Appendix II: Definitions, Terminology and Symbols in Colloid and Surface Chemistry; page 606)] to mean a liquid in which solid particles (here, fibers) are dispersed.

[0015] In the present invention, a suspension of microfibrillated cellulose fibers in a solvent has the consistency of a "paste" and exhibits non-Newtonian fluid properties (see Figure 1). Such suspensions / pastes may also be called "gels" (or "hydrogels" if the solvent is water).

[0016] According to the present invention, the parameter "dry matter" (also known as "solids content") refers to the amount of MFC remaining when all the solvent (typically water) has been removed, and is given as a weight percentage relative to the total weight of the suspension containing MFC and the solvent.

[0017] According to the present invention, the "solids content" of microfibrillated cellulose in a solvent is measured by oven drying (105 °C, 16 hours). Weigh a sample of 30 g or more into a pre-weighed aluminum weighing dish. Then dry this sample at 105 °C for 16 hours. Weigh the aluminum weighing dish with the dried material and calculate the dry matter based on the following formula: [(weight (dish plus sample after drying) - weight (dish)) × 100%] / weight (sample before drying)

[0018] Unless otherwise specified, all parameters mentioned in this disclosure are measured under standard conditions, i.e., at room temperature (20 °C), ambient pressure (1 bar), and ambient humidity of 50%.

[0019] Unless otherwise specified, all ratios given for the amounts of the components of the entire system are given as % by weight relative to the total weight of the contents of the system (i.e., excluding the package).

[0020] According to the present invention, the requirement that the contents are "enclosed" by the package means that the entire contents, i.e., the MFCs present as paste / suspension / gel, are contained within the package, and that the package, which is essentially non-extensible, almost non-extensible, or partially extensible, is present in an amount sufficient to assume a predetermined final outer dimension that can be achieved to the maximum extent without breaking or otherwise impairing the structural integrity of the package.

[0021] The package containing the contents is closed with respect to at least one opening, i.e., the package can be oriented in the direction of gravity without losing its contents. In the final realization of transportation, the package containing the contents is closed with respect to both (or all if more than two openings are present) openings / ends (see Figure 2, right panel, showing such a final realization of the present invention).

[0022] In an embodiment of the present invention, the package is a tube or tubular object, i.e., it has an essentially round outer periphery and is longitudinally elongated by 1.5 times or more, preferably 3 times or more, more preferably 4 times or more with respect to its width (length "l" > diameter "d").

[0023] According to the present invention, the package contains at least one polymer material, preferably two or more different polymer materials.

[0024] In an embodiment of the present invention, the at least one polymer is not an elastomer and the package is realized as a (composite) film.

[0025] In an embodiment of the present invention, the film has a thickness of 50 μm to 5 mm, preferably 100 μm to 2 mm, and more preferably 100 μm to 500 μm.

[0026] In an embodiment of the present invention, the package realized as a film, composite material, etc. has a tensile strength in the range of 5 MPa to 500 MPa, preferably 20 MPa to 300 MPa, when measured according to ASTM standard D882 - 02 (issued in June 2002).

[0027] As long as suitable tensile strength, elongation rate, and / or tensile modulus of the package can be achieved, there is no limitation regarding at least one polymer material [or any combination of two or more such materials, or at least one polymer material combined with any other suitable (non - polymer) material].

[0028] Also, as long as the package can contain MFC under typical storage and transportation conditions, there is no limitation regarding the type of polymer material (of the polymer material or any composite material containing at least one polymer). Also, there is no limitation regarding the number of layers, polymers, etc. (such as metals or fibers) constituting the package.

[0029] In an embodiment of the present invention, the at least one polymer is selected from polymers used in food package and non - food package applications. Thus, preferred polymers include polyethylene, especially HDPE, LDPE, and LLDPE (see the following discussion for more details), polypropylene, polycarbonate, PET, and any combination thereof or any combination with other materials such as fibers, metal coatings / foils, etc.

[0030] There are no restrictions on the dimensions of the package when the package, preferably a tubular package film, is filled with the MFC paste (contents) such that dimensional stability is achieved (see Figure 2 for a description of such a dimensionally stable system).

[0031] In embodiments of the present invention, the diameter of the system, i.e., the diameter and / or the longest dimension defining the cross-section of the package encompassing (and containing) the MFC paste, is from 2 cm to 50 cm, preferably from 5 cm to 30 cm, and more preferably from 10 cm to 25 cm.

[0032] In embodiments of the present invention, the weight of the system holding the MFC paste, i.e., one individual tubular structure, is from 1 kg to 50 kg per unit, preferably from 2 kg to 20 kg.

[0033] According to the present invention, the requirement that the contents of the system "consist essentially of" MFC means that the contents need to contain 90% by weight or more (relative to the total weight of the contents), preferably 95% by weight or more, and more preferably 99% by weight or more of MFC, i.e., microfibrillated cellulose fibers, suspended in a solvent, i.e., as a paste or gel as described above.

[0034] There are no limitations with respect to the solvent as long as the solvent can hold the MFC fibers in suspension under typical conditions for storage and transportation.

[0035] In embodiments of the present invention, the solvent is a hydrophilic solvent, preferably a polar solvent, and more preferably a protic solvent. Preferred solvents are water or alcohol or any combination of such solvents.

[0036] In a preferred embodiment, the solvent consists essentially of water, i.e., contains 90% or more, preferably 95% or more, and more preferably 99% or more water. "Water" is distilled water, processed water, or tap water as commonly used in industrial applications.

[0037] According to the present invention, the term "substantially round" means that the entire perimeter of the system (a package filled with contents until the package reaches its maximum outer dimensions without being torn or otherwise impaired) is described by a circle, and the relative difference between the major axis and the minor axis of the elliptical perimeter (clearly this difference is 0% for an ideal circle where the major axis and the minor axis are the same and correspond to a radius r) does not exceed 10%, preferably does not exceed 5%, with respect to the ideal circle [(πr 2 ) described by].

[0038] Thus, "oval" means that there are a major axis and a minor axis that are different from each other, but the difference does not exceed 30%, preferably does not exceed 20%.

[0039] Thus, the term "substantially rectangular" means that the entire perimeter of the system (a package filled with contents until the package reaches its maximum outer dimensions without being torn or otherwise impaired) is described by a rectangle, and the deviation from the ideal rectangle does not exceed 10%, preferably does not exceed 5%, with respect to the curvature of any side of the rectangle and / or with respect to any angle of the rectangle.

[0040] In a preferred embodiment, the substantially rectangular cross-section is substantially square.

[0041] The "round" or oval or "rectangular" or "square" geometry of the entire system is advantageous for the operation of the present invention because their "rolls" or "bricks" can then be further stacked and stably packaged, for example, in boxes and / or on pallets, when defined by the package and the microfibrillated cellulose applied thereto.

[0042] Furthermore, in addition to providing a firm and robust package shape, the inventors have found that when the microfibrillated cellulose is packaged according to the present invention, a compact package (equal pressure from all sides) stabilizes the microfibrillated cellulose and avoids sedimentation and / or separation effects, so that the water retention capacity of the microfibrillated cellulose is maintained essentially unchanged. On the other hand, when stored in a normal plastic bag, water droplets become visible after a short period, i.e., MFC cannot retain its water retention capacity.

[0043] Without being bound by theory, it is believed that, inter alia, the extrusion process as used during packaging and according to the present invention further stabilizes and homogenizes the MFC. Thus, when using the package of the present invention, the water retention properties of the MFC are generally retained in contrast to other known storage and transport systems.

[0044] According to the present invention, the system may include, in addition to the package and the content, further components, such as one or more labels or codes or any further (secondary) package.

[0045] The “microfibrillated cellulose” (MFC) according to the present invention is cellulose fibers that have been subjected to a mechanical treatment that results in an increase in specific surface area and a decrease in the size of the cellulose fibers in terms of cross-section (diameter) and / or length, and the decrease in size preferably results in “fibrils” having a diameter in the nanometer range and a length in the micrometer range, and is to be understood in relation to cellulose fibers.

[0046] In cellulose, which is the starting product for producing microfibrillated cellulose (typically present as "cellulose pulp"), there is no, or at least not significant, or not even detectable, part where individualized and "separated" cellulose "fibrils" can be found. Cellulose in wood fibers is an aggregate of fibers. In cellulose (pulp), elementary fibrils aggregate to form microfibrils, which further aggregate to form larger fibril bundles and ultimately cellulose-based fibers. The diameter of the wood-based fibers of cellulose pulp is typically in the range of 10 - 50 μm (the length of these fibers is even longer). When this cellulose fiber is microfibrillated, a heterogeneous mixture of "released" fibrils with a cross-sectional diameter and length in the range of nm - μm can be obtained. In the resulting microfibrillated cellulose, fibrils and bundles of fibrils can coexist.

[0047] In the microfibrillated cellulose ("MFC") described throughout this disclosure, individual fibrils or fibril bundles can be identified and easily distinguished by a conventional optical microscope, for example, at a magnification of 40 times.

[0048] According to a second aspect, all or some of the above-mentioned problems are solved by a process for a package of microfibrillated cellulose, which includes at least the following steps: · Providing a package that contains at least one polymer material and has an essentially round or oval or essentially rectangular perimeter when filled with contents up to its intended maximum outer dimensions, and has a length dimension that is essentially perpendicular to the area defined by the perimeter, and the perimeter is 1.5 times or more, preferably 3 times or more, more preferably 4 times or more of the length dimension; · Extruding microfibrillated cellulose from an extruder into the package until the package is filled throughout with microfibrillated cellulose to achieve its intended outer dimensions.

[0049] In an embodiment of the present invention, the process results in a system according to any of the embodiments disclosed above.

[0050] In an embodiment of the present invention, the process includes at least the following further steps: · Closing the package at all ends after filling the package with MFC such that the resulting system not only retains dimensional stability under typical conditions of transport and / or storage, but also achieves dimensional stability such that the contents are retained under said typical conditions of transport and / or storage; · Placing the MFC suspension into a vacuum filling device to further homogenize the suspension (paste) before extruding the MFC from the extruder.

[0051] Figure 3 shows a representative process for filling the package with MFC paste.

[0052] In step 1, the MFC paste is transported by a conveyor from the final dewatering step of the manufacturing process of MFC based on cellulose pulp. This MFC is then transported to a pump and / or an extruder.

[0053] The MFC may be transported in portions (as described in Figure 3) or continuously. In step 1, other suitable means (other than a conveyor) may be used.

[0054] In step 2, preferably in an extruder, the MFC is further mixed, homogenized, and extruded into the package through a nozzle, preferably at a constant rate.

[0055] There is no limitation on the extruder, and any extruder suitable for treating pastes of the consistency and viscosity of MFC may be used. As an example, any extruder / pump system commercially available from Karl Schnell Company, particularly a KS pump system based on the principle of a positive displacement vacuum pump, i.e., any vacuum filling system, may be used. This design is particularly suitable for high-viscosity products.

[0056] Therefore, in the embodiments of the present invention, the extruder is a vacuum filling unit or includes a vacuum filling unit.

[0057] In the embodiments of the present invention, the entire pump is emptied during the extrusion process.

[0058] In step 3, preferably in a clipping machine, a tubular package (containing MFC as the content) is closed, preferably with two clips at each end of the tube.

[0059] A conveyor is used for transportation between different stations [step (4) in Figure 3]. The entire process may preferably be fully automated.

[0060] Any device used in this process is a labeling device (5) for labeling each tube with, for example, a batch number, product type, manufacturing date, etc., a case erector (7) for corrugated cardboard or cardboard boxes for transportation, and a palletizing machine for packing corrugated cardboard or cardboard boxes onto a pallet.

[0061] In the embodiments of the present invention, a robot (6) is used to lift the filled tube and lower it into a cardboard box for cartons and / or to lift corrugated cardboard or cardboard boxes. A "single box" (one tube) or a "multi-box" (more than two or three tubes) can be lifted.

[0062] According to a third aspect of the present invention, all or some of the above-described problems are solved by using a system as described in any of the above embodiments for the storage and / or transportation of MFC.

[0063] The present invention will be described in more detail below with reference to the accompanying drawings, which are merely illustrative.

Brief Description of the Drawings

[0064]

Figure 1

Figure 2

Figure 3

DETAILED DESCRIPTION OF THE INVENTION

[0065] As already shown above, the at least one polymer used in the package of the present system may be selected from polymers used in food package and non-food package applications. Thus, preferred polymers include polyethylene, especially HDPE, LDPE, and LLDPE, polypropylene, polycarbonate, PET, and any combination thereof, or any combination with other materials such as fibers, metal coatings / foils, etc.

[0066] Low density polyethylene, i.e., LDPE, is a thermoplastic package that is easy to process and can be blended with other polymers and / or additives such as EVA, HDPE, LLDPE, fillers, pigments, etc. to modify its basic properties.

[0067] Linear low density polyethylene (LLDPE) has properties similar to LDPE, but has higher tensile and impact strength and better heat sealability, while LDPE has higher transparency, ease of processing, and higher gloss.

[0068] Metallocene polyethylene, i.e., mPE, is a low density polyethylene produced using a metallocene catalyst. Rapid sealing is possible with this technology. The resulting package has excellent puncture resistance and oxygen permeability and good break tensile strength, and is much stronger than ordinary polyethylene.

[0069] High-density polyethylene, i.e., HDPE, is a flexible but harder and stronger milky white translucent thermoplastic material with good impact strength and excellent puncture resistance. HDPE is more rigid than other polyethylene films, which is an important property for packages that need to maintain their shape.

[0070] Polypropylene, i.e., PP, is a thermoplastic material with high transparency, high gloss, and good tensile strength. The two most important types of PP are cast polypropylene (CPP) and biaxially oriented polypropylene (BOPP). Both types have high gloss, outstanding optical properties, good or excellent heat-sealing performance, high heat resistance, and good dimensional stability. Generally, CPP has higher tear and impact resistance, better cold-temperature performance, and better gas-barrier and heat-sealing properties, while BOPP has higher tensile strength, higher modulus of elasticity (rigidity), lower extensibility, and lower haze.

[0071] Polycarbonate (PC) is an amorphous engineering thermoplastic material with excellent mechanical, optical, electrical, and thermal properties. It is extremely tough and has remarkable impact resistance and high optical transparency. PC films are used in film applications that require high scratch resistance, chemical resistance, weather resistance, and highly clear transparency.

[0072] Vinyl film, also known as polyvinyl chloride, i.e., PVC, is a versatile and inexpensive thermoplastic material with good dimensional stability, good impact strength, and excellent weather resistance. It can be easily die-cut and printed with conventional screen and offset printing methods.

[0073] The polyester film is a high-performance, very clear thermoplastic made from polyethylene terephthalate (PET). Compared to other common plastic films, the PET film has high tensile strength, excellent dimensional stability, low moisture absorption, and good retention of physical properties over a fairly wide temperature range.

[0074] Polyvinylidene chloride (PVDC) is a synthetic thermoplastic produced by the polymerization of vinylidene chloride. The most common type is the biaxially oriented film. PVDC has remarkable oxygen and humidity barrier properties, is printable using common ink systems, and provides excellent adhesion strength, high heat resistance, and low water absorption.

[0075] Polyamide (PA), also known as nylon, is a transparent printable thermoplastic with a relatively high melting point, exceptional strength and toughness, and good oxygen barrier properties. The two most common types are the non-oriented and biaxially oriented nylon films. Biaxially oriented polyamide, i.e., BOPA film, can be used for various applications where particularly high gas barrier properties are required.

[0076] As already described above, in principle, as long as the fiber bundles present in the original cellulose pulp in the manufacturing process of MFC are sufficiently comminuted so that the average diameter of the resulting fibers / fibrils is in the nanometer range, and thus a larger surface of the cellulose-based material is created compared to the surface available in the original cellulose material, any type of microfibrillated cellulose (MFC) can be used for the contents of the package when used in accordance with the present invention. MFC may be prepared according to any process described in the art, including the prior art specifically cited in the "Background Art" section above.

[0077] The origin of the cellulose used to prepare MFC According to the present invention, there are no specific restrictions regarding the origin of cellulose and thus the origin of microfibrillated cellulose. In principle, the raw material of cellulose microfibrils may be any cellulose-based material, particularly wood, annual plants, cotton, linen, wheat straw, ramie, bagasse (from sugarcane), suitable algae, jute, sugar beet, citrus fruits, waste from the food processing industry or energy crops, or cellulose derived from bacteria or animals, such as cellulose derived from tunicates.

[0078] In a preferred embodiment, a wood-based material of either hardwood or softwood, or both (a mixture), is used as the raw material. More preferably, softwood is used as the raw material, either as a single type or as a mixture of different softwood types. Bacterial microfibrillated cellulose is also preferred due to its relatively high purity.

[0079] Modified (derivatized) and unmodified (non-derivatized) cellulose / MFC In particular, the microfibrillated cellulose according to the present invention may be unmodified with respect to its functional groups, or may be physically modified or chemically modified, or both.

[0080] Chemical modification of the surface of cellulose microfibrils can be achieved by various possible reactions of the surface functional groups of cellulose microfibrils, more specifically hydroxyl functional groups, preferably by oxidation, silylation reaction, etherification reaction, condensation with isocyanates, alkoxylation reaction with alkylene oxides, or condensation or substitution reaction with glycidyl derivatives. The chemical modification may be carried out before or after the defibrillation step.

[0081] Cellulose microfibrils may also be modified, in principle, by a physical route, either by adsorption or spraying or coating or encapsulation on the surface of the microfibrils. Preferred modified microfibrils can be obtained by physical adsorption of at least one compound. MFC may also be modified by association with an amphiphilic compound (surfactant).

[0082] However, in a preferred embodiment, the microfibrillated cellulose is not physically modified.

[0083] In a preferred embodiment of the present invention, the microfibrillated cellulose is prepared by a process comprising at least the following steps: (a) subjecting the cellulose pulp to at least one mechanical pretreatment step; (b) subjecting the mechanically pretreated cellulose pulp from step (a) to a homogenization step, which results in fibrils and fibril bundles having a reduced length and diameter with respect to the cellulose fibers present in the mechanically pretreated cellulose pulp from step (a), and microfibrillated cellulose is obtained; The homogenization step (b) comprises compressing the cellulose pulp from step (a) and subjecting this cellulose pulp to a pressure drop.

[0084] The mechanical pretreatment step is preferably a refining step or includes a refining step. The purpose of the mechanical pretreatment is to "beat" the cellulose pulp in order to improve the accessibility of the cell wall, i.e., to increase the surface area.

[0085] Preferably, the refiner used in the mechanical pretreatment step includes at least one rotating disk. In this case, the cellulose pulp slurry is subjected to a shearing force between the at least one rotating disk and at least one stationary disk.

[0086] Prior to the mechanical pretreatment step, or in addition to the mechanical pretreatment step, enzymatic (pre)treatment of cellulose pulp is an optional additional step that may be preferred for some applications. Regarding enzymatic pretreatment combined with microfibrillation of cellulose, the contents of WO 2007 / 091942 are incorporated herein by reference. Any other type of pretreatment including chemical pretreatment is also within the scope of the present invention.

[0087] In the homogenization step (b) carried out after the (mechanical) pretreatment step, the cellulose pulp slurry from step (a) is passed through a homogenizer one or more times, preferably two or more times, as described in PCT / EP2015 / 001103 (the contents of which are incorporated herein by reference).

Examples

[0088] Example 1: Preparation of microfibrillated cellulose The MFC used in the system / package of the present invention is commercially available and is marketed by Borregaard as "Exilva F01-V" based on cellulose pulp derived from Norwegian spruce (softwood).

[0089] The MFC in step (i) was present as a paste with a solids content of 10%. The solvent was water.

[0090] Example 2: Packaging of microfibrillated cellulose Figure 3 shows a representative process for filling a package with the MFC paste from Example 1.

[0091] In step 1, the MFC paste from the final dehydration step of the process for producing MFC from cellulose pulp is transported by a conveyor. This MFC is then transported to an extruder. The MFC was transported in small portions (as shown in Figure 3).

[0092] In step 2, the MFC is further mixed, homogenized, and extruded through a nozzle into the package at a constant rate. The extruder was a KS pump system (vacuum filler) such as those commercialized by Karl Schnell. Without being bound by theory, the extrusion process, as used in the packaging and according to the present invention, is thought to further stabilize and homogenize the MFC. Thus, when using the package of the present invention, in contrast to other known storage and transport systems, the water retention properties of the MFC are generally maintained.

[0093] In step 3, in a clipping machine, the tubular package (containing MFC as the content) is closed at each end of the tube using two clips.

[0094] A conveyor is used for transportation between different stations [step (4) in Figure 3]. The entire process is fully automated.

[0095] Further devices used in this process are a labeling device (5) for attaching labels such as batch number, product type, manufacturing date, etc. to each tube, a case erector (7) for cardboard or carton boxes for transportation, and a palletizing machine for packing cardboard or carton boxes onto a pallet.

[0096] A robot (6) is used to lift the filled tube and lower it into a cardboard carton and / or to lift a cardboard or carton box.

[0097] Overall, many successful attempts have been made to homogenize the MFC and fill the package with MFC using an extruder.

[0098] Figure 2 shows that the product is completely homogenized after the package has been removed.

Explanation of symbols

[0099] 5 Labeling device 6 Robot 7-Case Ejector

Claims

1. A system comprising: - At least one package containing at least one polymeric material; - Contents of the package completely enclosed by the package, the contents containing at least 90% by weight of microfibrillated cellulose present in at least one solvent, based on the total weight of the contents; The microfibrillated cellulose and the solvent form a suspension of the microfibrillated cellulose in the solvent, The solids content of the microfibrillated cellulose relative to the total weight of the suspension is 3 w / w% to 30 w / w%, and the package, when completely filled with the contents, is essentially round or essentially rectangular or oval, defining the outer perimeter of the entire system, i.e., the packaged microfibrillated cellulose, and The length of the system is at least 1.5 times the maximum width defining the cross-section of the outer perimeter, The term "substantially round" means that the entire perimeter of the system (a package filled with contents until the package reaches its maximum outer dimension without tearing or being otherwise impaired) is described by a circle, where, with respect to the relative difference between the major axis and the minor axis of the perimeter of an ellipse, the deviation from the ideal circle described by (πr ２ ) does not exceed 10%, The term "essentially rectangular" means that the entire perimeter of the system (the package filled with the contents until it reaches its maximum outer dimensions without tearing or being otherwise damaged) is described by a rectangle, where the deviation from an ideal rectangle does not exceed 10% with respect to the curvature of any side of the rectangle and / or with respect to any angle of the rectangle, and The package is completely filled with the contents, System.

2. The system according to claim 1, wherein the solids content of the microfibrillated cellulose relative to the total weight of the suspension is 5 w / w% to 12 w / w%.

3. The system according to claim 1 or 2, wherein the length of the system is at least 3 times the maximum width defining the cross-section of the outer perimeter.

4. The system according to any one of claims 1 to 3, wherein the package is essentially round.

5. The system according to any one of claims 1 to 4, wherein the at least one polymer is not an elastomer.

6. The system according to any one of claims 1 to 5, wherein the package is realized as a film.

7. The system according to claim 6, wherein the film has a thickness of 50 μm to 5 mm.

8. The system according to any one of claims 1 to 7, wherein the tensile strength of the package, when measured in accordance with ASTM standard D882-02 issued in June 2002, is in the range of 5 MPa to 500 MPa.

9. The system according to any one of claims 1 to 8, wherein the package has a tensile strength in the range of 20 MPa to 300 MPa when measured in accordance with ASTM standard D882-02 issued in June 2002.

10. The system according to any one of claims 1 to 9, wherein the at least one polymer of the package is selected from polymers used for food package and non-food package applications, and includes at least one of polyethylene, polypropylene, polycarbonate, PET, and any combination thereof, or any combination with other materials.

11. The system according to any one of claims 1 to 10, wherein the diameter of the system, i.e., the diameter of the package containing the microfibrillated cellulose as the content, is 2 cm to 50 cm.

12. The system according to any one of claims 1 to 11, wherein the diameter of the system, i.e., the diameter of the package containing the microfibrillated cellulose as the content, is 5 cm to 30 cm.

13. The system according to any one of claims 1 to 12, wherein the weight of the system, i.e., the weight of each individual structure holding the microfibrillated cellulose content, is 1 kg to 50 kg per unit.

14. The system according to any one of claims 1 to 13, wherein the solvent contains 90% or more water.

15. The system according to any one of claims 1 to 14, wherein the solvent contains 99% or more water.

16. A process for manufacturing the system according to any one of claims 1 to 15, the process including at least the following steps: - Providing a package that contains at least one polymer material and has an essentially round perimeter or an essentially rectangular or oval perimeter when filled with the content to its intended maximum outer dimensions, and has a length dimension that is essentially orthogonal to the area defined by the perimeter, and the length dimension is at least twice the width; and - Extruding microfibrillated cellulose from an extruder into the package until the package is filled with microfibrillated cellulose throughout and reaches its intended outer dimensions. The term "substantially round perimeter" means that the entire perimeter of the system (a package filled with contents until the package reaches its maximum outer dimensions without rupturing or being otherwise impaired) is described by a circle, where, with respect to the relative difference between the major axis and the minor axis of an elliptical perimeter, the deviation from the ideal circle described by (πr ２ ) does not exceed 10%, and The term "essentially rectangular perimeter" means that the entire perimeter of the system (a package that is filled with the contents until the package reaches its maximum outer dimensions without being torn or otherwise impaired) is described by a rectangle, where the deviation from an ideal rectangle does not exceed 10% with respect to the curvature of any side of the rectangle and / or with respect to any angle of the rectangle. Process. **Claim 17** The process according to claim 16, wherein the process comprises at least the following further steps: - Closing the package at all ends after filling the package with microfibrillated cellulose such that the resulting system achieves dimensional stability such that it not only maintains dimensional stability under typical conditions of transport and / or storage but also retains the contents under said typical conditions of transport and / or storage; - Placing the microfibrillated cellulose suspension into a vacuum filling device in order to further homogenize the suspension (paste) before extruding the microfibrillated cellulose from an extruder. **Claim 18** Use of the system according to any one of claims 1 to 15 for the storage or transport or storage and transport of microfibrillated cellulose. **Claim 19** The process according to claim 16 or 17, wherein the microfibrillated cellulose is prepared by a process comprising at least the following steps: (a) Subjecting cellulose pulp to at least one mechanical pretreatment step; (b) Subjecting the mechanically pretreated cellulose pulp of step (a) to a homogenization step that results in fibrils and fibril bundles of reduced length and diameter relative to the cellulose fibers present in the mechanically pretreated cellulose pulp of step (a), whereby microfibrillated cellulose is obtained; The homogenization step (b) comprises compressing the cellulose pulp from step (a) and subjecting this cellulose pulp to a pressure drop. Process. **Claim 20** The use according to claim 18, wherein the microfibrillated cellulose is prepared by a process comprising at least the following steps: (a) Subjecting cellulose pulp to at least one mechanical pretreatment step; Step (b): A step of subjecting the mechanically pretreated cellulose pulp of step (a) to a homogenization step, which results in fibrils and fibril bundles having a reduced length and diameter with respect to the cellulose fibers present in the mechanically pretreated cellulose pulp of step (a), and microfibrillated cellulose is obtained; The homogenization step (b) includes compressing the cellulose pulp from step (a) and subjecting this cellulose pulp to a pressure drop. Use.

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