Mold unit for drying a wet molded container body and method for drying such a container body

Abstract

The mold unit (1) comprises a mold body (2) having an inner wall section (4) defining a molding cavity (6) for the container body. The molding cavity (6) extends along and about a longitudinal axis (X). The mold body (2) defines primary channels (11) that are distributed about the molding cavity (6), for channeling a fluid alongside the molding cavity (6) to evacuate water and / or steam out of the molding cavity (6) during drying of the container body. The mold body (2) further defines a secondary channel (12) arranged such that a downstream end of the secondary channel (12) is fluidly connected, through a connection pathway (13), with an upstream end of the primary channels (11), such that the fluid can be channeled through the secondary channel (12), through the connection pathway (13), and through the primary channels (11).

Description

[0001] ALPLA Werke Alwin Lehner GmbH & Co KG P62915 / WO

[0002] 1

[0003] MOLD UNIT FOR DRYING A WET MOLDED CONTAINER BODY AND METHOD FOR DRYING SUCH A CONTAINER BODY

[0004] 1. Field of the invention The present invention is directed to a mold unit for drying a container body manufactured by wet molding a material, preferably a fiber-based material. The invention is also directed to a method for drying such a container body.

[0005] 2. Technical background There is a general trend to manufacture containers out of a fiber-based material, for example paper bottles. The fiber-based material can be wet-molded to be compressed into a shape nearing the desired bottle shape. After the wet molding step, the wet-molded product can be received in a molding cavity of a mold unit, to be dried up, and then further shaped into the desired bottle shape. The mold body of the mold unit can usually be made out of polypropylene (PP), which has a maximum service temperature of around too degrees C.

[0006] However, when the mold unit is running continuously for a long time, the mold body tends to heat up over time, as it cannot be cooled down long enough. Eventually, the mold body might deform and its dimensions might change due to repeated thermal expansion. The thermal expansion may deteriorate the geometric fitting between the parts of the mold unit, for example between the mold body and an outer shell holder, which can in turn lead to cracks on the mold body.

[0007] 3. Summary It is an object of the present disclosure to provide a mold unit that contributes to obviating or at least alleviating some or all of the afore-mentioned problems, in particular by enhancing the cooling of the mold body. An aspect of the present disclosure provides a mold unit for drying a container body manufactured by wet molding a material, preferably a fiber-based material, the mold unit comprising a mold body having an inner wall section defining a molding cavity for receiving the container body, the molding cavity extending along and about a longitudinal axis, wherein the mold body defines a plurality of primary channels that are i) distributed about the longitudinal axis and the molding cavity, and ii) configured for channeling a ALPLA Werke Alwin Lehner GmbH & Co KG P62915 / WO

[0008] 2 fluid alongside the molding cavity so as to evacuate water and / or steam that can flow out of the molding cavity during drying of the container body received in the molding cavity, and wherein the mold body further defines at least one secondary channel arranged such that a downstream end of the at least one secondary channel is fluidly connected, through a connection pathway, with an upstream end of at least one of the primary channels, such that the fluid can be channeled through the at least one secondary channel, through the connection pathway, and through some or all of the primary channels.

[0009] Thus, as the hollow primary and secondary channels extend through the mold body, the total mass of the mold body can be reduced, and so can the amount of heat building up in the mold body during manufacturing cycles. Further, as a fluid can flow through the primary and secondary channels, it can contribute to cooling down the mold body. As the mold body can cool down to some extent on every manufacturing cycle, the mold body and the mold unit are capable of running for longer time with only limited deformations by thermal expansion and limited crack formation, especially at the interface between parts having different thermal expansion coefficients.

[0010] The primary channels may be the ones that primarily contribute to cooling down the molding cavity, to which they may stand closer than the secondary channels. A cooling fluid may flow from the upstream-arranged secondary channels to the downstream- arranged primary channels.

[0011] In some embodiments, when the mold unit is in a closed, manufacturing configuration, the molding cavity may have a symmetry of revolution around the longitudinal axis. Thus, the container body, e.g. a bottle body, can have a round and symmetric shape. The container body may have any shape defining a hollow volume, for example the shape of a bottle body, possibly with a neck portion, a shoulder portion, a main portion and a base portion.

[0012] In some embodiments, a distance separating any one of the primary channels and the molding cavity may be smaller than 3.0 mm and larger than 0.5 mm, preferably larger than 1.0 mm. This distance depends on the size and shape desired for the container body. These minimal and maximal distances enable to strike a balance, for containers of common sizes and shapes, between i) a sufficient cooling and draining by the evacuation fluid through the primary channels on the one hand, and ii) the minimum thickness of the mold body walls required to confer a sufficient mechanical strength to the mold body on the other hand. In some embodiments, a gap separating two consecutive primary channels around the longitudinal axis may be comprised between 1 mm and 3 mm. Thus, the evacuating air ALPLA Werke Alwin Lehner GmbH & Co KG P62915 / WO

[0013] 3 flowing through the primary channels can cool the mold unit efficiently and uniformly, which avoids generation of too large thermal stresses in between two consecutive primary channels.

[0014] Optionally, for a given mold unit and an average size of container body, the largest width or diameter of the molding cavity (e.g. in the main region), may be about 120-140 mm, and the smallest width or diameter of the molding cavity (e.g. in the neck region) maybe about 30 mm.

[0015] - According to an embodiment, the mold body may define a plurality of secondary channels that are distributed, preferably evenly distributed, i) about the longitudinal axis and / or ii) about the molding cavity and, preferably also, iii) about the plurality of primary channels.

[0016] Thus, all the hollow secondary channels can contribute to reducing the amount of heat throughout the entire mold body and foster a uniform cooling and drying of the container during manufacturing operations. The distribution of the channels may herein be considered when the mold unit is in a closed configuration.

[0017] Preferably, the number of primary channels may be comprised between 12 and 24 (around the entire molding cavity). Likewise, the number of secondary channels maybe comprised between 10 and 50. The number of primary and / or secondary channels can thus be commensurate to the size and shape of the molding cavity, and it depends on the size and shape desired for the container body. These minimal and maximal numbers of primary or secondary channels enable to strike a balance, for containers of common sizes and shapes, between i) an appropriate flowrate of evacuation fluid through the channels on the one hand, and ii) the minimum thickness of the intermediate ribs in between primary or secondary channels that is required to confer a sufficient mechanical strength to the mold body on the other hand.

[0018] Preferably, all of the primary channels may have substantially the same cross-sectional area when measured in a plane perpendicular to the longitudinal axis. Likewise, all of the secondary channels may have substantially the same cross-sectional area when measured in a plane perpendicular to the longitudinal axis. As each one of the channels has about the same cross-sectional area as any other one of the channels, the flow of the evacuating fluid (air) can be similar or equal from one channel to the other, thus contributing to an efficient evacuation of water and / or steam.

[0019] - According to an embodiment, each of the secondary channels maybe fluidly connected i) to at least one of the primary channels, ii) to exactly one of the primary channels, or iii) to another one of the primary channels. ALPLA Werke Alwin Lehner GmbH & Co KG P62915 / WO

[0020] 4

[0021] Thus, in addition to reducing the mass of the mold body, each one of the secondary channels can contribute to cooling down the mold body when channeling a cooling fluid through the mold body.

[0022] - According to an embodiment, the connection pathway may comprise at least one connection channel and / or at least one connection space and / or at least one connection tube.

[0023] Thus, the connection pathway can allow a cooling fluid to flow between the primary and secondary channels, either in a main direction (connection channel, connection tube), or in many directions (connection space, connection plenum). In the case of a connection space or a connection plenum space, a large flowrate of cooling fluid can flow between the primary and secondary channels.

[0024] - According to an embodiment, the mold unit may further comprise a cover configured to cover a plenum region of the mold body so as to define the connection pathway between the mold body and the cover. Thus, forming the connection pathway can be made quite easily and yet accurately. The region of the mold body that is covered by the cover is a totally or partially hollow region. The cover can seal the plenum region to force the cooling fluid that flows out of the or each secondary channel to flow into the primary channels.

[0025] - According to an embodiment, the or each secondary channel may extend substantially parallel to the longitudinal axis, the or each secondary channel being preferably formed by a rectilinear bore, and / or the or each primary channel may extend substantially parallel to the longitudinal axis, the or each primary channel being preferably formed by a rectilinear bore.

[0026] Thus, the primary and / or secondary channels can minimize the pressure drop in a flow of cooling fluid, which in turn enhances the cooling efficiency in the mold body.

[0027] When the or each secondary channels is formed as a bore, it does not significantly alter the mechanical strength of the mold body, while it prevents from accumulating too much heat in the mold body.

[0028] In some embodiments, each secondary channel among some or, preferably, all of the secondary channels may have a diameter or a width of between 5 mm and 15 mm, preferably between 8 mm and 12 mm.

[0029] - According to an embodiment, the primary channels may be distributed in a circular arrangement about the longitudinal axis, and / or the secondary channels, when there is a plurality thereof, may be distributed in a circular arrangement about the longitudinal axis, the respective distance from the or each ALPLA Werke Alwin Lehner GmbH & Co KG P62915 / WO

[0030] 5 secondary channel to the longitudinal axis being preferably larger than the respective distance from the or each primary channel to the longitudinal axis.

[0031] In other words, the primary channels may occupy a tubular volume with a circular basis in the mold body. Likewise, the secondary channels may occupy a tubular volume with a circular basis in the mold body.

[0032] Thus, such arrangement of the primary and secondary channels can prevent too much heat from building up in the mold body while not significantly altering the mechanical strength of the mold body.

[0033] In the preferred configuration, the secondary channels can surround the primary channels. Thus, while the primary channels can contribute to draining heat out of a central region of the mold body, the or each secondary channel can contribute to draining heat out of a peripheral region of the mold body.

[0034] - According to an embodiment, the molding cavity may extend between a top end and a bottom end along the longitudinal axis, the molding cavity may have, at least in one cross-sectional plane comprising the longitudinal axis, an outer contour configured such that a lateral portion of the outer contour extends between the top end and the bottom end, the lateral portion may be configured such that the distance of the outer contour to the longitudinal axis varies along the longitudinal axis, and in the at least one cross-sectional plane, at least one, preferably some, more preferably all, of the primary channels may extend non-linearly so as to follow at least the lateral portion.

[0035] Thus, the shape of some or all of the primary channels can be conformal to the outer contour, hence to the shape of the container body received in the molding cavity. As a result, the fluid for evacuating water and / or steam can flow within a respective channel with relatively constant velocity, direction, and pressure drop. This can improve resistance to thermo-mechanical stresses.

[0036] Said distance between the longitudinal axis and the outer contour of the molding cavity may be measured in a direction perpendicular to the longitudinal axis. Preferably, the primary channels may extend generally vertically when the mold unit is in a manufacturing configuration in which drying of the container body can be operated. In the manufacturing configuration, the top end of the molding cavity lies above the bottom end of the molding cavity.

[0037] The top end of the molding cavity maybe located near the upstream ends of the primary channels or, alternatively, near the downstream ends of the primary channels. ALPLA Werke Alwin Lehner GmbH & Co KG P62915 / WO

[0038] 6

[0039] Conversely, the bottom end of the molding cavity may be located near the downstream ends of the primary channels or, alternatively, near the upstream ends of the primary channels. The terms “top”, “bottom”, “upper”, “lower” and their derivatives maybe read herein as referring to the manufacturing configuration in which drying of the container body can be operated.

[0040] In some embodiments, the outer contour may define, preferably along the longitudinal axis, a neck region, a base region, and a main region arranged between the neck region and the base region, so as to conform respectively to a neck portion, a base portion, and a main portion of the container body. In some embodiments, each of the primary channels may be angled and / or curved along at least part of its extension axis to extend non-linearly so as to follow at least the lateral portion of the outer contour.

[0041] - According to an embodiment, each of the primary channels may extend through the mold body from a top axial side of the mold body to a bottom axial side of the mold body. Thus, the channels can contribute to efficiently drying up and cooling down the container body all along the mold body.

[0042] In some embodiments, the channels may exit at opposite faces of the mold body. Alternatively, the channels may enter from an upper side of the mold body, then extend vertically to a lower side, where they may exit to an outer side again. - According to an embodiment, each of the primary channels may extend along a respective extension axis, and wherein each of the primaiy channels may be designed such that its cross-sectional area, measured in a plane perpendicular to the extension axis, is substantially constant along most of, preferably along the whole of, its extension axis. Thus, the flow of the fluid for evacuating water and / or steam can be substantially constant along each primary channel, which helps increase the resistance of the dried- up container body.

[0043] For some or all of the primary channels a ratio of the minimum cross-sectional area Amin over the maximum cross-sectional area Amax may be in a range of 1 < Amax(p) / Amin(p) < 1,5. Likewise, for some or all of the secondary channels a ratio of the minimum cross-sectional area Amin over the maximum cross-sectional area Amax may be in a range of 1 < Amax(s) / Amin(s) < 1,5. It follows that the primary and / or the secondary channels can have a constant cross-sectional area along their respective extension axes. Thus, the flow of the fluid for evacuating water and / or steam can be constant or almost constant along each primary and / or secondary channel. ALPLA Werke Alwin Lehner GmbH & Co KG P62915 / WO

[0044] 7

[0045] - According to an embodiment, the mold unit may further comprise a fluid delivering unit configured to deliver a fluid, preferably a gas, for example air, out of the primary channels, so as to support evacuation of steam and / or water out of the mold unit.

[0046] Thus, the fluid delivering unit can make the evacuating fluid circulate through the primary and secondary channels along with water and / or steam to be evacuated out of the mold unit.

[0047] - According to an embodiment, the mold unit may further comprise a heating unit, preferably a microwave heater, for heating the container body received in the molding cavity. Thus, the heating unit can heat part or all of the inner wall section so as to dry up the container body by evaporating water therefrom.

[0048] In some embodiments, the mold unit may further comprise an inflatable core selectively insertable into the molding cavity, particularly inside the container body being received in the molding cavity, wherein the inflatable core is configured to expand towards the inner wall section in order to press the container body against the inner wall section.

[0049] In some embodiments, each of the primary channels is designed such that the cross- sectional areas of two randomly selected primary channels, measured in a plane perpendicular to the respective extension axes, are substantially equal in any plane perpendicular to the longitudinal axis. Thus, each of the channels can have almost the same cross-sectional area as any other one of the channels. The flows of the fluid for evacuating water and / or steam can be substantially equal among the channels, for example where the neck and shoulder portions are formed. This contributes to an efficient evacuation of water and / or steam out of the mold unit. In the present disclosure, two physical quantities may be viewed as being “substantially equal” when their ratio is comprised between 0,80 and 1,25, preferably between 0,95 and 1,05.

[0050] In some embodiments, the cross-sectional areas of said two randomly selected primary channels may have a ratio comprised between 0,75 and 1,25, preferably between 0,85 and 1,15, more preferably between 0,95 and 1,05. Thus, each of the channels has the same cross-sectional area as any other one of the channels. This contributes to a highly efficient evacuation of water and / or steam out of the mold unit.

[0051] Similarly, the cross-sectional areas of two randomly selected secondary channels may have a ratio comprised between 0,75 and 1,25, preferably between 0,85 and 1,15, more preferably between 0,95 and 1,05.

[0052] - According to an embodiment, the mold body may be made partially or totally out of a material selected in the group consisting in: polypropylene (PP), Cyclic Olefin Copolymer

[0053] (COC), and amorphous polyimide (PEI). ALPLA Werke Alwin Lehner GmbH & Co KG P62915 / WO

[0054] 8

[0055] Thus, the mold body can absorb no or only a few microwaves, which can in turn reduce the heat building up in it.

[0056] - According to an embodiment, the mold body may have porous walls configured to drain water and steam out of the molding cavity into the primary channels to help evacuate the water and / or steam from the mold unit, the porous walls being preferably made out of a 3D-printed material.

[0057] Thus, the porous walls allow an efficient evacuation of water and / or steam to dry up and cool down the container body.

[0058] Preferably, the mold body may be composed of a first mold body part and a second mold body part, such that the mold body can be placed:

[0059] - in a closed configuration in which the molding cavity is formed by juxtaposition of the first mold body part and the second mold body part, and

[0060] - in an open configuration in which the mold body is open and the first mold body part is distant, hence disconnected, from the second mold body part. Thus, in the closed configuration, the molding cavity is defined as a union of at least two separable parts. The mold unit may be maneuverable to place the mold body selectively in the open configuration or in the closed configuration. The closed configuration corresponds to the manufacturing configuration.

[0061] - Another aspect of the present disclosure provides a method for drying a container body manufactured by wet molding a material, preferably a fiber-based material, the method comprising:

[0062] - implementing a mold unit according to any one of the preceding claims,

[0063] - placing the container body to be dried in the molding cavity,

[0064] - optionally, placing an inflatable core inside the container body received in the molding cavity, and expanding the inflatable core to press the container body against the wall inner section, such that water flowing out of the molding cavity can be drained out of the mold unit via the primary channels,

[0065] - heating the container body received in the molding cavity, preferably by subjecting it to microwaves, such that steam flowing out of the molding cavity can be drained out of the mold unit via the primary channels,

[0066] - optionally, at least during heating of the container body, delivering a fluid, preferably a gas like air, through the primary channels and, preferably, through the or each secondary channel, through the connection pathway, and through the primary channels, to help evacuate the water and / or steam out of the mold unit via the primary ALPLA Werke Alwin Lehner GmbH & Co KG P62915 / WO

[0067] 9 channels, wherein the fluid is preferably delivered from an upper side to a lower side of the respective primary channel, wherein preferably the fluid is a cooling fluid so as to cool the mold body at least during heating the container body, and

[0068] - taking the dried container body out of the molding cavity. In some embodiments, the fiber-based material may comprise or consist in pulp material, cellulose fibers such as cellulose fibers obtained from wood, and / or non-wood fibers, in particular hemp, straw, bagasse, bamboo and / or other agricultural fibers. In some embodiments, the fiber-based material may comprise a fiber content of at least 60% or at least 70% or at least 80% or at least 90% or at least 95%. Thus, such fiber- based materials can be suitably handled, wetted, deformed, and dried, while having an increased biodegradability and, possibly, recyclability.

[0069] The words “comprise”, “include”, “have” and their derivatives are to be interpreted inclusively rather than exclusively. The term “and / or” used in the context of “X and / or Y” should be interpreted as “X,” or “Y,” or “X and Y.”

[0070] 4. Brief description of drawings

[0071] Further features, details and advantages of the present invention are described hereinafter, in particular in relation to the appended figures, which illustrate, schematically and not on scale, some of the afore-described aspects, embodiments and implementations thereof, and in which:

[0072] Fig. 1 shows a cutaway perspective view of a half of a mold unit according to a first embodiment of the present disclosure;

[0073] Fig. 2 shows a top view along arrow II of Fig. 1;

[0074] Fig. 3 shows a cutaway perspective view of a half of a mold unit according to a second embodiment of the present disclosure;

[0075] Fig. 4 shows a top view along arrow IV of Fig. 1;

[0076] Fig. 5 shows a flowchart of a method according to an embodiment of the present disclosure. 5. Detailed description

[0077] Fig. 1 to 3 illustrate a mold unit 1 for drying a not shown container body that is manufactured by wet molding a fiber-based material, which may comprise cellulose fibers. The wet molding step of the manufacturing process maybe performed previously in another, not shown mold unit, then the semi-finished container body may be ALPLA Werke Alwin Lehner GmbH & Co KG P62915 / WO

[0078] 10 transferred to the mold unit 1, where the drying step of the manufacturing process may be performed.

[0079] The mold unit 1 comprises a mold body 2, which has an inner wall section 4. The inner wall section 4 defines a molding cavity 6 for receiving the container body. The molding cavity 6 extends about a longitudinal axis X. The molding cavity 6 may extend, along the longitudinal axis X, between a top end 6.1 and a bottom end 6.2.

[0080] The mold body 2 maybe composed of a first mold body part 2A and a second mold body part 2B, such that the mold body 2 can be placed:

[0081] - in a closed configuration (Fig. 2) in which the molding cavity 6 is formed by juxtaposition of the first mold body part 2A and the second mold body part 2B, and

[0082] - in a not shown open configuration in which the mold body 2 is open and the first mold body part 2A is distant, hence disconnected, from the second mold body part 2B.

[0083] The mold unit 1 may be maneuverable to place the mold body 2 selectively in the open configuration or in the closed, manufacturing configuration. The mold body 2 may be made out of polypropylene (PP).

[0084] The mold body 2 defines a plurality of primary channels 11, which are distributed about the longitudinal axis X and the molding cavity 6. The primary channels 11 are configured for evacuating water and / or steam that can flow out of the molding cavity 6 during diying of the container body in the molding cavity 6. The primaiy channels 11 are evenly distributed about the longitudinal axis X (closed mold unit 1), thus promoting a uniform cooling of the molding cavity 6 to evenly dry the container body.

[0085] Further, the mold body 2 defines a plurality of secondary channel 12. The primary channels 11 may be arranged closer to the molding cavity 6 than the secondary channels 12. The secondary channels 12 may be evenly distributed (closed mold unit 1) i) about the longitudinal axis X, ii) about the molding cavity 6, and iii) about the plurality of primary channels 11. All the hollow secondary and primary channels 12 and 11 can contribute to reducing the mass of the mold body 2, hence the amount of heat building up throughout the entire mold body 2.

[0086] Each secondary channel 12 may extend substantially parallel to the longitudinal axis X. Each secondary channel 12 may preferably be formed by a rectilinear bore, for example of 10 mm diameter. Likewise, each primary channel 11 may extend generally parallel to the longitudinal axis X, except in the neck region of the molding cavity 6. Each primary channel 1 may preferably be formed by a rectilinear bore, for example of 10 mm diameter.

[0087] Most or all of the primary channels 11 may have substantially the same cross-sectional area when measured in a plane perpendicular to the longitudinal axis X. Likewise, most ALPLA Werke Alwin Lehner GmbH & Co KG P62915 / WO

[0088] 11 or all of the secondary channels 12 may have substantially the same cross-sectional area when measured in a plane perpendicular to the longitudinal axis X.

[0089] The mold unit 1 may further comprise a fluid delivering unit 7, which is configured to deliver a fluid, for example pressurized air, out of the primary channels 11, so as to support evacuation of steam and / or water out of the mold unit 1. The flows of evacuation air are materialized in Fig. 1 by arrows F. The evacuation air, or a cooling fluid F, may flow through primary channels 11.

[0090] The mold unit 1 may further comprise a cover 14, which is relatively small and which may cover a part of the molding cavity 6. The cover may be arranged upstream the primary channels 11. The cover 14 can guide the cooling fluid F into the primary channels 11.

[0091] Also, the mold unit 1 may comprise a heating unit 8, preferably a microwave heater, for heating the container body received in the molding cavity 6. The heating unit 8 can heat the inner wall section 4 to dry up the container body by evaporating water therefrom.

[0092] As derivable from Fig. 1 and 2, there may be about 18 secondary channels 12 defined by the mold body 2. There maybe about 12 to 24 primary channels 11, depending on various parameters, for example the type of material that has to be molded and dried, the size of the container body, the time of drying and / or cooling the molding cavity 6 etc.

[0093] The primary channels 11, the secondary channels 12, and the longitudinal axis X may extend generally vertically when the mold unit 1 is in a manufacturing configuration in which drying of the container body can be operated. Every primary channel 11 may extend all along the mold body 2 from a top axial side 2.1 of the mold body 2 to a bottom axial side 2.2 of the mold body 2. Likewise, every secondary channel 12 may extend all along the mold body 2.

[0094] In the manufacturing configuration, the top end 6.1 of the molding cavity 6 may lie above the bottom end 6.2 of the molding cavity 6. The top end 6.1 of the molding cavity 6 may be located near the upstream ends 11.1 of the primary channels 11 or, alternatively, near the downstream ends of the primary channels. Conversely, the bottom end 6.2 of the molding cavity 6 may be located near the downstream ends 11.2 of the primary channels 11 or, alternatively, near the upstream ends of the primary channels. Every primary channel 11 may have an upstream end 11.1 and a downstream end 11.2, defined by the orientation of the flows through the primary channel 11. The upstream end 11.1 of a respective primary channel 11 may be located near the top end 6.1 of the molding cavity 6. Conversely, the downstream end 11.2 of a respective primary channel 11 may be located near the bottom end 6.2 of the molding cavity 6. Likewise, every ALPLA Werke Alwin Lehner GmbH & Co KG P62915 / WO

[0095] 12 secondary channel 12 may have a downstream end 11.1 and an upstream end 12.2, defined by the orientation of the flows through the secondary channel 12.

[0096] As visible on Fig. 2, the primary channels 11 maybe distributed in a circular arrangement about the longitudinal axis X. The primary channels 11 may occupy a not shown tubular volume with a circular basis in the mold body 2. The secondary channels 12 may be distributed in a circular arrangement about the longitudinal axis X so as to surround the primary channels 11. The secondary channels 12 may occupy a not shown tubular volume with a circular basis in the mold body X. Thus, the respective distance from each secondary channel 12 to the longitudinal axis X can be larger than the respective distance from each primary channel 11 to the longitudinal axis X.

[0097] The molding cavity 6 may have, at least in one cross-sectional plane comprising the longitudinal axis X, an outer contour 6.4 that may be configured such that a lateral portion 6.6 of the outer contour 6.4 extends between the top end 6.1 and the bottom end 6.2, herein not only in the plane of Fig. 2 but also in several other cross-sectional planes comprising the longitudinal axis X. The lateral portion 6.6 of the outer contour 6.4 may be configured such that the distance from the outer contour 6.4 to the longitudinal axis X varies along the longitudinal axis X, when measured in a direction perpendicular to the longitudinal axis X. In other words, the molding cavity may have a curved shape.

[0098] In the example of Fig. 1 and 2, the outer contour 6.4 is designed to manufacture a container body that is in the form of a bottle body. Nevertheless, the container body may have any shape defining a hollow volume. In a cross-sectional plane, e.g. in the plane of Fig. 1, every primary channel 11 may extend non-linearly, with a curved and / or angled outline, to follow the lateral portion 6.6 of the outer contour 6.4.

[0099] The outer contour 6.4 may define a neck region, a shoulder region, a base region, and a main region arranged between the neck region and the base region, so as to conform respectively to a neck portion, a shoulder portion, a base portion, and a main portion of the bottle body, from top end 6.1 to bottom end 6.2 along the longitudinal axis X, a neck portion, a main portion and a base portion. The shoulder portion may be joining the neck portion to the main portion, and the main portion may be joining the shoulder portion and the base portion.

[0100] The container body, e.g. bottle body, can have a round and symmetric shape when the molding cavity 6 has a symmetry of revolution around the longitudinal axis X (closed mold unit 1), as is the case in Fig. 1 and 2. The upstream end 11.1 and the downstream ALPLA Werke Alwin Lehner GmbH & Co KG P62915 / WO

[0101] 13 end 11.2 of a primary channel 11 can be located respectively at the neck portion and at the base portion of the bottle body.

[0102] Every primary channel 11 and / or every secondary channel 12 can have mostly the same cross-sectional area along its extension axis X11 (Fig. 1), to enable a constant flow of evacuating air F therein. Every primary channel 11 can have the same cross-sectional area as any other one of the primary channels 11. Likewise, every secondary channel 12 can have the same cross-sectional area as any other one of the secondary channels 12. The flows F of air for evacuating water and / or steam can be substantially equal among the primary channels 11. The mold body 2 may have porous walls 4.1 surrounding most or all of the inner wall section 4. The porous walls 4.1 maybe configured to drain water and / or steam out of the molding cavity into the primary channels 11 to help evacuate the water and / or steam from the mold unit 6. In other words, the porous walls fluidly connect the molding cavity 6 to the primary channels 11. The porous walls 4.1 may preferably be made out of a 3D- printed material. When the heating unit 8 is heating the inner wall section 4, the porous walls 4.1 allow an efficient evacuation of water and / or steam to flow therethrough, hence out of the molding cavity 6, to dry up and cool down the container body.

[0103] - Fig. 3 and 4 illustrate a mold unit 1 according to a further embodiment of the present disclosure. The mold unit 1 of Fig. 3 and 4 may be similar to the mold unit 1 depicted in relation to Fig.i and 2. The detailed description given above in relation to Fig. 1 and 2 applies to Fig. 3 and 4, apart from the following notable differences.

[0104] Similarly to the mold unit 1 of Fig.i and 2:

[0105] - The mold unit 1 comprises a mold body 2 with an inner wall section 4 that defines a molding cavity 6. - The molding cavity 6 may extend, along and about the longitudinal axis X, between a top end 6.1 and a bottom end 6.2.

[0106] - The mold body 2 defines a plurality of similar primary channels 11, which may extend all along the mold body 2 and which may be evenly distributed in a circular arrangement about the longitudinal axis X and the molding cavity 6. - The mold body 2 defines a plurality of similar secondary channel 12, which extend all along the mold body 2 and which maybe evenly distributed in a circular arrangement ALPLA Werke Alwin Lehner GmbH & Co KG P62915 / WO

[0107] 14 about i) the longitudinal axis X, ii) the molding cavity 6, and iii) the primary channels 11.

[0108] - The mold unit 1 may comprise a fluid delivering unit 7 and a heating unit 8.

[0109] - The molding cavity 6 may have an outer contour 6.4 designed to manufacture a bottle body. Every primary channel 11 may extend non-linearly to follow the lateral portion

[0110] 6.6 of the outer contour 6.4.

[0111] - The mold body 2 may have porous walls 4.1 surrounding the inner wall section 4.

[0112] As notable differences with the mold unit 1 of Fig.1 and 2, a connection pathway 13 fluidly connects the downstream ends 12.2 of the secondary channels 12 with the upstream ends 11.1 of the primary channels 11, in the arrangement of the secondary channels 12 shown in Fig.3 and 4. The connection pathway 13 is thus fluidly connected: i) with a respective downstream end 12.1 of each secondary channel 12 and ii) with a respective upstream end 11.1 of each primary channel 11, such that the fluid can be channeled through each secondary channel 12, through the connection pathway 13, and through the primary channels 11, successively. The cooling fluid F, for example evacuation air moved by the fluid delivering unit 7, may flow from the upstream-arranged secondary channels 12 to the downstream-arranged primary channels 11.

[0113] The mold unit 1 may further comprise a cover 15 configured to cover and, preferably, seal a hollow plenum region of the mold body 2 so as to define all or part of the connection pathway 13 between the mold body 2 and the cover 15. The cover 15 may be arranged upstream the primary channels 11 to force the cooling fluid F that flows out of each secondary channel 12 to flow into the primary channels 11. By contrast, in Fig. 1-2, the cover 14 of mold unit 1 is smaller than the cover 15 of Fig. 3-4, and it guides the evacuation air F from outside the mold body 2 into the primary channels 11 without necessarily flowing through secondary channels 12.

[0114] All secondary channels 12 may be fluidly connected to all primary channels 11 via the plenum covered by cover 15. The cover 15 may be fastened, for example by means of screws, to the mold body 2. The connection pathway 13 may comprise a connection space formed by the plenum located under the cover 15. In Fig. 3-4, the connection pathway 13 can allow the cooling fluid to flow between the secondary and primary channels 12 and 11 in any directions, which can yield a large flowrate of cooling fluid F between the secondary and primary channels 12 and 11.

[0115] Fig. 5 illustrates a method 101 for drying the container body, which maybe manufactured using the mold unit 1 of Fig. ito 2 or of Fig. 3 to 4, by wet molding a fiber-based material. The method 101 comprising: ALPLA Werke Alwin Lehner GmbH & Co KG P62915 / WO

[0116] 15

[0117] - 102) implementing the mold unit 1 of Fig. 1-2 or of Fig. 3-4,

[0118] - 104) placing the container body to be dried in the molding cavity 6,

[0119] - 106) optionally placing a not shown inflatable core inside the container body received in the molding cavity 6, and expanding the inflatable core to press the container body against the inner wall section 4, such that water flowing out of the molding cavity can be drained out of the mold unit 1 via the primary channels,

[0120] - 108) heating the container body received in the molding cavity 6, preferably by subjecting it to microwaves emitted by the heating unit 8, such that steam flowing out of the molding cavity can be drained out of the mold unit 1 via the primary channels 11,

[0121] - 110) optionally, at least during heating of the container body, delivering a fluid, preferably a gas like air, through the primary channels 11 to help evacuate the water and / or steam out of the mold unit 1 via the primary channels 11, wherein the fluid is preferably delivered from an upper side to a lower side of the respective primary channel 11, wherein preferably the fluid is a cooling fluid so as to cool the mold body 2 at least during heating the container body, and

[0122] - 112) taking the dried container body out of the molding cavity 6.

[0123] The steps 106 and 108 may be performed in two consecutive mold units, resp. molding cavities: a not shown first mold unit dedicated to wet molding and pressing water out of the molding cavity, and the mold unit 1 as the second unit dedicated to heating the container body and evacuating steam out of the mold unit 6 via the primary channels 11.

[0124] The invention defined in the appended claims is not limited to the afore-described objects, aspects, embodiments and implementations, most of which maybe combined.

Claims

ALPLA Werke Alwin Lehner GmbH & Co KG P62915 / WO16Claims1. Mold unit (1) for drying a container body manufactured by wet molding a material, preferably a fiber-based material, the mold unit (1) comprising a mold body (2) having an inner wall section (4) defining a molding cavity (6) for receiving the container body, the molding cavity (6) extending along and about a longitudinal axis (X), wherein the mold body (2) defines a plurality of primary channels (11) that are i) distributed about the longitudinal axis (X) and the molding cavity (6), and ii) configured for channeling a fluid alongside the molding cavity (6) so as to evacuate water and / or steam that can flow out of the molding cavity (6) during drying of the container body received in the molding cavity (6), and wherein the mold body (2) further defines at least one secondary channel (12) arranged such that a downstream end (12.2) of the at least one secondary channel (12) is fluidly connected, through a connection pathway (13), with an upstream end (11.1) of at least one of the primary channels (11), such that the fluid can be channeled through the at least one secondaiy channel (12), through the connection pathway (13), and through some or all of the primary channels (11).

2. Mold unit (1) according to claim 1, wherein the mold body (2) defines a plurality of secondary channels (12) that are distributed, preferably evenly distributed, i) about the longitudinal axis (X) and / or ii) about the molding cavity (6) and, preferably also, iii) about the plurality of primary channels (11).

3. Mold unit (1) according to claim 2, wherein each of the secondaiy channels (12) is fluidly connected i) to at least one of the primary channels (11), ii) to exactly one of the primary channels (11), or iii) to another one of the primary channels (11).

4. Mold unit (1) according to any one of the preceding claims, wherein the connection pathway (13) comprises at least one connection channel and / or at least one connection space and / or at least one connection tube.

5. Mold unit (1) according to any one of the preceding claims, further comprising a cover (14; 15) configured to cover a plenum region of the mold body (2) so as toALPLA Werke Alwin Lehner GmbH & Co KG P62915 / WO17 define the connection pathway (13) between the mold body (2) and the cover (14; 15)-6. Mold unit (1) according to any one of the preceding claims, wherein the or each secondary channel (12) extends substantially parallel to the longitudinal axis (X), the or each secondary channel (12) being preferably formed by a rectilinear bore, and / or wherein the or each primary channel (11) extends substantially parallel to the longitudinal axis (X), the or each primary channel (11) being preferably formed by a rectilinear bore.

7. Mold unit (1) according to any one of the preceding claims, wherein the primary channels (11) are distributed in a circular arrangement about the longitudinal axis (X), and / or wherein the secondary channels (12), when there is a plurality thereof, are distributed in a circular arrangement about the longitudinal axis (X), the respective distance from the or each secondary channel (12) to the longitudinal axis (X) being preferably larger than the respective distance from the or each primary channel (11) to the longitudinal axis (X).

8. Mold unit (1) according to any one of the preceding claims, wherein the molding cavity (6) extends between a top end (6.1) and a bottom end (6.2) along the longitudinal axis (X), wherein the molding cavity (6) has, at least in one cross-sectional plane comprising the longitudinal axis (X), an outer contour (6.4) configured such that a lateral portion (6.6) of the outer contour (6.4) extends between the top end (6.1) and the bottom end (6.2), wherein the lateral portion (6.6) is configured such that the distance of the outer contour (6.4) to the longitudinal axis (X) varies along the longitudinal axis (X), and wherein, in the at least one cross-sectional plane, at least one, preferably some, more preferably all, of the primary channels (11) extend(s) non-linearly so as to follow at least the lateral portion (6.6).ALPLA Werke Alwin Lehner GmbH & Co KG P62915 / WO189. Mold unit (1) according to any one of the preceding claims, wherein each of the primaiy channels (11) extends through the mold body (2) from a top axial side (2.1) of the mold body (2) to a bottom axial side (2.2) of the mold body (2).

10. Mold unit (1) according to any one of the preceding claims, wherein each of the primaiy channels (11) extends along a respective extension axis (X11), and wherein each of the primary channels (11) is designed such that its cross-sectional area, measured in a plane perpendicular to the extension axis (X11), is substantially constant along most of, preferably along the whole of, its extension axis (X11).

11. Mold unit (1) according to any one of the preceding claims, further comprising a fluid delivering unit (7) configured to deliver a fluid, preferably a gas, for example air, out of the primaiy channels (11), so as to support evacuation of steam and / or water out of the mold unit (1).

12. Mold unit (1) according to any one of the preceding claims, further comprising a heating unit (8), preferably a microwave heater, for heating the container body received in the molding cavity (6).

13. Mold unit (1) according to any one of the preceding claims, wherein the mold body(2) is made partially or totally out of a material selected in the group consisting in: polypropylene (PP), Cyclic Olefin Copolymer (COC), and amorphous polyimide (PEI).

14. Mold unit (1) according to any one of the preceding claims, wherein the mold body (2) has porous walls (4.1) configured to drain water and steam out of the molding cavity (6) into the primary channels (11) to help evacuate the water and / or steam from the mold unit (1), the porous walls (4.1) being preferably made out of a 3D- printed material.ALPLA Werke Alwin Lehner GmbH & Co KG P62915 / WO1915. Method (101) for drying a container body manufactured by wet molding a material, preferably a fiber-based material, the method comprising:(102) implementing a mold unit (1) according to any one of the preceding claims, - (104) placing the container body to be dried in the molding cavity (6),(106) optionally, placing an inflatable core inside the container body received in the molding cavity (6), and expanding the inflatable core to press the container body against the wall inner section, such that water flowing out of the molding cavity (6) can be drained out of the mold unit (1) via the primary channels (11),(108) heating the container body received in the molding cavity (6), preferably by subjecting it to micro waves, such that steam flowing out of the molding cavity (6) can be drained out of the mold unit (1) via the primary channels (11),(110) optionally, at least during heating of the container body, delivering a fluid, preferably a gas like air, through the or each secondary channel (12), through the connection pathway, and through the primary channels (11) to help evacuate the water and / or steam out of the mold unit (1) via the primary channels (11), wherein the fluid is preferably delivered from an upper side to a lower side of the respective primary channel (11), wherein preferably the fluid is a cooling fluid so as to cool the mold body (2) at least during heating the container body, and(112) taking the dried container body out of the molding cavity (6).

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