Three-dimensional molded part made of fibrous material and molding tool for producing molded parts made of fibrous material

Abstract

A three-dimensional molded part made of fibrous material and a molding tool for producing molded parts made of fibrous material are described, wherein the three-dimensional molded part is produced in a manufacturing process under pressure and thermal influence, wherein a surface of the molded part has at least one design element and / or functional element, which is formed by at least one area with reduced material thickness, wherein the material thickness of the at least one area decreases with an increasing molded part height in one molding direction.

Description

Technical field

[0001] A three-dimensional molded part made of fibrous material and a molding tool for producing molded parts made of fibrous material are described. background

[0002] Fiber-containing materials are increasingly used to manufacture packaging for food (e.g., trays, capsules, boxes, etc.) and consumer goods (e.g., electronic devices, etc.), as well as beverage containers. These fiber-containing materials can contain natural fibers, which are obtained, for example, from renewable resources or recycled paper. The natural fibers can be mixed with water and, if necessary, other additives such as starch in a pulp and then shaped. Additives can also affect the color, barrier properties, and mechanical properties. A pulp can contain, for example, 0.1 to 10% by weight of natural fibers. The proportion of natural fibers can vary depending on the manufacturing process used for the packaging, etc., and the product properties of the product being manufactured. Fibers such as...Natural fibers can also be introduced into molds in a dry state and processed or shaped within them. Alternatively, such fibers can be processed into raw materials for subsequent shaping. Raw materials for further processing can include, for example, sheets or webs, such as airlaid, fluff pulp, paper, etc., as well as multi-layer arrangements of the aforementioned materials, made from a fiber-containing material, which are then formed in a mold.

[0003] In the production of products or molded parts from fibrous materials, during a so-called wet process, the evaporating water is routinely extracted during pressing at high temperatures and pressures. Even in dry processes, steam extraction can occur during pressing at high temperatures and pressures if the fibrous material has a water content of approximately 20% by weight or more, or if it has been locally moistened. To extract the steam, the mold surfaces of the molding tools have small openings connected to corresponding channels and devices. During pressing, small protrusions form on the surfaces of the molded parts, with the fibrous material being forced into these openings. The extraction process can further facilitate the formation of these protrusions.

[0004] These raised areas result from the extraction process. As the moisture content of the material being compressed increases in the cavities of the molding tools, more and more steam is generated, which must be vented through openings on at least one surface of the mold. The raised areas are visible and perceptible to the touch on a finished molded part.

[0005] However, these raised sections are perceived as disruptive in terms of design specifications and aesthetics, resulting in very low demand for alternative molded parts made from renewable and easily recyclable fiber-containing materials, which can also be compostable. This is a significant disadvantage, especially considering the goal of increasing the use of sustainable products. Furthermore, these raised sections have the drawback that, when used as capsules for coffee machines or lids for drinking cups, they do not sit flush with the contact surfaces (e.g., the brewing chamber of a coffee capsule) or do not fit optimally against the rim of the cup, thus preventing a sufficient seal. Additionally, these raised sections can make drinking from a lid more difficult. Task

[0006] In contrast, the task is to provide a solution that eliminates the disadvantages of the prior art, enables the production of molded parts made of fibrous material, and provides molded parts made of fibrous material that are simple in design, are not subject to functional limitations in the use of molded parts due to protrusions resulting from manufacturing technology, and meet aesthetic requirements. Solution

[0007] The aforementioned problem is solved by a three-dimensional molded part made of fibrous material, which is produced in a manufacturing process under pressure and thermal influence, wherein a surface of the molded part has at least one design element and / or functional element, which is formed by at least one area with reduced material thickness, wherein the material thickness of the at least one area decreases with an increasing molded part height in one molding direction.

[0008] The integration of design and / or functional elements on the surface of molded parts made of fibrous material with decreasing thickness offers the advantage that, for example, raised areas or other decorative or informational elements can be incorporated into these areas, particularly embossed elements, which do not protrude beyond the surface of the molded part, or only minimally, since these elements can extend from an area that is recessed from the surface. This allows for the production of molded parts that have no protruding elements on the surface in the area of ​​the design and / or functional element compared to adjacent surface areas. Furthermore, design and / or functional elements can be integrated into a surface without visually disrupting it.

[0009] The design elements and / or functional elements do not have the same material thickness across their entire length, but the difference is barely perceptible. Recessed areas in molded parts made of fibrous material are generally visually and tactilely noticeable when they exhibit a certain reduction in material thickness. In the presented solution, the reduction in material thickness does not begin abruptly but rather gradually and can, for example, end abruptly at a lower end in the mold direction. To create essentially sharply defined areas despite the continuous reduction in material thickness, a less pronounced reduction in material thickness can initially be implemented in one area of ​​the design element and / or functional element, followed by an area with a more pronounced reduction in material thickness.For optimal presentation of design elements and / or functional elements, a reduction in material thickness can begin before the design element and / or functional element, so that the required reduced material thickness is then achieved in the area of ​​the design element and / or functional element, which is visually and / or haptically perceptible. This means that the "initial area" of the reduction in the direction of the shape does not fall within the area of ​​the design element and / or functional element and is not perceptible haptically and / or visually.

[0010] In further embodiments, the surface can have an orientation inclined relative to a vertical axis of the molded part, so that a cross-sectional area of ​​the molded part increases in the molding direction.

[0011] In further embodiments, the design element and / or the functional element may have at least one raised area formed by fibrous material which, during the manufacture of the molded part, was sucked and / or pressed into a corresponding opening in a mold surface of a molding tool when steam escaping from the fibrous material during compression was removed.

[0012] In further embodiments, the at least one raised area can be arranged in a first surface section, which has a different design compared to an adjacent at least one second surface section, with the at least one raised area being integrated into the design of the first surface section. This also includes areas with reduced material thickness. In particular, this can also include depressions, transitions between edge, side and / or bottom areas, embossing, etc.

[0013] In further embodiments, the surface, the design element, and / or the functional element may have protrusions formed by fibrous material. These protrusions are drawn and / or pressed into corresponding openings in a mold surface of a molding tool during the production of the molded part as steam escaping from the fibrous material during compression is removed. The protrusions form at least one pattern. In further embodiments, the at least one pattern may represent a product feature, a product representation, a product usage instruction, and / or a disposal instruction for the molded part. For example, symbols, letters, numbers, etc., may be formed by indentations, protruding areas, and other surface finishes (e.g., texture, roughness, etc.), with the at least one pattern integrated into such a surface section. Furthermore, a pattern may, for example, form a functional element, which, for example,It serves to snap a first molded part together with a corresponding part. A functional element can, for example, form an undercut, which is provided, for example, in cups and lids to ensure a secure hold.

[0014] The arrangement of raised areas as patterns offers, on the one hand, a visually appealing appearance, which can also serve to display product information, usage and waste instructions, and on the other hand, can take a technical aspect into account, whereby patterns can be formed, for example, in the form of a line that facilitates insertion into a receiving space (e.g., brewing chamber for a coffee capsule) or prevents incorrect insertion (formation of raised areas to provide elements according to the principle of "Poka Joke").

[0015] In further versions, the at least one pattern can be integrated at least section by section into a transition between at least a first surface section and a second surface section of the surface and / or into a design element on the surface.

[0016] When integrating at least one pattern into a first surface section with a different design compared to a second surface section, the at least one pattern can be integrated into a section or area (first surface section) of the molded part's surface that already differs in its design (shape, depth, thickness, etc.) and thus also visually and haptically from the remaining surface area or adjacent areas (second surface section). This ensures that the raised areas of the at least one pattern are not visually disruptive because they are integrated into an area that is already designed differently for aesthetic and / or technical reasons, and also do not interfere with the use of the molded part because, due to their integration into a differently designed area, the raised areas are not, for example, separated from a contact surface.The surface should be level, so that no "resting points", "spacer bumps" or the like are formed.

[0017] For example, raised areas of at least one pattern can be incorporated into regions of a molded part with reduced material thickness, such that no raised areas protrude from the surface to the extent that their protruding ends are essentially flush with the surface contour of the surrounding areas of the second surface section. In other words, raised areas cannot extend beyond a surface plane that spans both the first and second surface sections. Furthermore, raised areas can also be intentionally projected from a surface plane, where they are part of a design feature.

[0018] The design of a first surface section can vary. For example, it can include transitions, general raised areas (i.e., thickened sections), design elements, recesses, decorative features, undercuts, etc. These raised areas can be located on an outer and / or inner surface. They typically extend perpendicularly from the surface and have small dimensions. For example, raised areas can have diameters of 0.5 to 2 mm or corresponding cross-sections. The height of raised areas can range from 0.2 to 1.5 mm. The dimensions can also vary depending on the thickness of the molded part in the area of ​​the material layer associated with the surface, the dimensions of the molded part, the material used, and the intended application.Molded parts can be designed in various ways and, for example, have a round or polygonal cross-section.

[0019] In further versions, the at least one design element, functional element and / or pattern can extend over a wall area, an edge area and / or a floor area of ​​a molded part.

[0020] In further embodiments, the protrusions can be arranged on an outer surface of the molded part and extend away from the outer surface of the molded part.

[0021] In further embodiments, at least one raised element can have a cross-section that is at least partially oval, elongated, polygonal, or round. This raised element can be part of a design element or constitute an essential component thereof. In further embodiments, patterns can contain information and / or represent a functional element, serving, for example, as a spacer, guide, and / or marker. In further embodiments, at least one spacer element can be designed as retaining or spacer ribs (e.g., in containers for hot or cold food / beverages) or as a rough gripping surface with multiple raised elements.

[0022] In further versions, at least one raised area can itself be designed as a design element and / or functional element, wherein the at least one raised area has areas with different material thicknesses.

[0023] In further versions, the fiber-containing material can contain at least 50% by weight of plant fibers and / or cellulose fibers.

[0024] The aforementioned problem is also solved by a molding tool for producing molded parts from fibrous material according to one of the preceding embodiments, wherein the molding tool has at least one molding surface for pressing fibrous material into a three-dimensional molded body, wherein the at least one molding surface surrounds a molding space for pressing the fibrous material, and wherein the at least one molding surface has at least one molding element that increasingly protrudes from the at least one molding surface in the molding direction.

[0025] In this case, the at least one forming element can only project into the mold space to such an extent that it runs parallel to the forming direction, whereby the corresponding mold surface section of the mold surface, in particular in the area for a side wall of a molded part to be produced, is inclined to the forming direction, i.e. the cross-section or diameter of the mold space increases in the forming direction.

[0026] This results in a simple generation of design elements, which have a recess for the formation of design elements and / or functional elements, whereby no undercuts or movable tool components are required in the mold for the formation of the design elements and / or functional elements and areas with less material thickness.

[0027] The molded parts specified above in relation to the molded part also apply accordingly to a molding tool for the production of such molded parts, whereby molded parts can be manufactured using simple means without a complex and vulnerable tool design, which meets the above requirements and solves the task mentioned at the outset.

[0028] Further features, designs and advantages will become apparent from the following presentation of exemplary embodiments with reference to the figures. Brief description of the characters

[0029] The drawings show: Fig. 1: A schematic representation of a molded part made of fibrous material in a perspective view; Fig. 2: A schematic representation of another molded part made of fibrous material in a perspective view; Fig. 3: Schematic representations of the formation of a design element on the surface of a molded part made of fibrous material; Fig. 4: A schematic representation of a sectional view of a molded part made of fibrous material with differently formed raised areas and design elements; Fig. 5: Schematic representations of the formation of raised areas and design elements; Fig. 6 a schematic representation of a mold for the production of molded parts from fibrous material; Fig. 7 a schematic representation of the formation of a design element on the surface of a molded part made of fibrous material in a further embodiment; and Fig. 8 schematic representations of a molded part with functional elements. Detailed description of implementation examples

[0030] The following are exemplary embodiments of the technical teaching described herein, with reference to the figures. The same reference numerals are used in the figure descriptions for identical components, parts, and processes. Components, parts, and processes that are immaterial to the technical teaching disclosed herein or that are obvious to a person skilled in the art are not explicitly shown. Features given in the singular are also included in the plural unless explicitly stated otherwise. This applies in particular to terms such as "a" or "an".

[0031] Fig. 1 Figure 1 shows a schematic representation of a molded part 100 made of fibrous material in a perspective view. The in Fig. 1 The molded part 100 shown is designed as a capsule. In the illustrated embodiment, the capsule is designed as a coffee capsule and serves to hold coffee powder. Before filling and after the production of the Fig. 1 The molded part 100 shown can have an inner receiving chamber or surface coated (laminated, coated, etc.) to provide a barrier. Alternatively or additionally, after filling and sealing, the capsule can have its outer surface coated (laminated, coated, etc.) to achieve a barrier effect. Another alternative or additional way to provide barrier properties for molded part 100 is by incorporating additives into the fiber-containing material.

[0032] The molded part 100 has a base 102 with a support ring 104. The support ring 104 projects from the surface of the base 102. The molded part 100 has an adjoining circumferential side wall 110. The side wall 110 is slightly inclined relative to the base 102, with the diameter of a receiving chamber of the molded part 100 increasing from the base 102 to an edge 150. In the illustrated embodiment, the molded part 100 is essentially rotationally symmetrical. The side wall 110 has a thickened or stepped ring 112. In the region of the ring 112, the material thickness or the thickness of the side wall 110 can be greater than in the remaining region. Alternatively, the cross-section or diameter of the side wall 110 can increase in the region of the ring 112 to provide a substantially constant wall thickness across the entire side wall 110.A second transition 116, which has a radius, is formed between the ring 112 and the side wall 110. A first transition 114 from the ring 112 to an edge 150 also has a radius. In the embodiment shown, protrusions 160 are formed at various locations on the surface 106 of the molded part 100.

[0033] Three design elements 130 are integrated into the side wall 110, which are used when pressing the fiber-containing material in a mold 200 (see e.g. Fig. 6 ) are trained. The design elements 130 are in Fig. 1 designed as coffee beans, since the embodiment represents a capsule for coffee. It is evident that other design elements 130 can also be created by a corresponding shaping and form of the surface 106. The design elements 130 have a region 140 with reduced wall thickness, as shown with reference to Fig. 3a ) and Fig. 7The side wall 110 forms a second surface section 122 on its surface, which here has a curved shape. The sections with the design elements 130 form first surface sections 120.

[0034] In the execution according to Fig. 1 are elevations 160, which occur during a forming process in the hot pressing of fibrous material due to the removal of steam, which escapes from the fibrous material during pressing under high pressure (0.2 to 300 N / mm 2< ) and high temperatures (120 - 300 °C), via corresponding steam bores (openings 234; see e.g. Fig. 6 ) in the form surfaces 232 of a form tool 200, integrated into the design of the first surface sections 120 or design elements 130.

[0035] By integrating the raised areas 160 into the design of the decorative elements 130 ("coffee bean"), these raised areas 160 are barely perceptible and blend seamlessly into the overall design, both visually and haptically. In the exemplary embodiment with the coffee bean, the decorative element 130 has a ridge 132 in the first surface section 120. The ridge 132 protrudes from the adjacent areas 140, which each have a smaller material thickness or wall thickness than the ridge 132 and the second surface section 122. The raised areas 160 on the ridges 132 are thus integrated into the different design of the decorative element 130 compared to the second surface section 122.

[0036] Furthermore, protrusions 160 are integrated into the transitions 114, 116 and a transition area between the base ring 104 and the base 102, or into the base ring 104 itself, so that these protrusions have no significant influence on the use of the molded part 100, i.e., they do not form any protruding elements located on visible surfaces of the surface 106, nor do they interfere with contact with corresponding surfaces of a processing machine (e.g., a coffee machine). The protrusions 160 on the base 102 and on the edge 150 can also be omitted in other embodiments. In the exemplary embodiment, these are shown as an embodiment option on further first surface sections, which differ from the remaining surface 106, in particular the surface 106 of the side wall 110 in the second surface section 122, due to their orientation and arrangement as well as their surface properties. The base 102, for example, has...The surface is offset from the base ring 104, so that the central protrusions 160 do not interfere with the use of the molded part 100 and are also barely perceptible visually. The rim 150 has a rougher surface, so that the protrusions 160 on the rim 150 are barely perceptible both visually and haptically and are also not located on relevant functional surfaces, especially for later use (e.g., coffee machine).

[0037] Fig. 2Figure 1 shows a schematic representation of another molded part 100 made of fibrous material in a perspective view. In the embodiment shown, several protrusions 160 on the surface of the side wall 110 form a pattern 162, as schematically indicated by the dashed line. A pattern 162 can also extend beyond the side wall 110 to the edge 150 and / or the base 102. In further embodiments, the base 102 and / or the edge 150 can also have a pattern 162 consisting of several protrusions 160. A pattern 162 can, instead of a curved shape as shown in Figure 1, be a pattern 162. Fig. 2The pattern shown can also form a letter, a number, a symbol, or a corresponding string of letters, numbers, and / or symbols. In further embodiments, a pattern 162 can also form functional elements, which can be designed as retaining or spacer ribs (e.g., in containers for hot or cold food / beverages) or as a rough gripping surface with a plurality of protrusions 160.

[0038] Fig. 3 Figure 1 shows schematic representations of the formation of a design element 130 on the surface of a molded part 100 made of fibrous material, where the formation on an outer surface 106 is described here. In further embodiments, an analogous design can also be provided on an inner surface 108 if a side wall 110 is inclined accordingly.

[0039] Fig. 3aFigure 1 shows both a design element 130, which is shaped like a coffee bean, and a section through the design element 130. The design element 130 is formed by at least one area 140 with reduced material thickness, wherein the material thickness of the at least one area 140 decreases with an increasing part height FH in a forming direction FD.

[0040] The design element 130 has a region 140 with reduced material thickness, as can be seen particularly in the sectional view. In a first sub-region 142, the side wall 110 has a decreasing material thickness in the region of the design element 130, which continues to decrease until reaching a second sub-region 144, where it reaches its maximum. The material thickness along the web 132 remains unchanged in the exemplary embodiment. In further embodiments, the material thickness of the web 132 can also decrease, with the degree of reduction differing from that of the regions 140 in order to achieve a visually and haptically perceptible difference between the regions 140 and a web 132. This may be necessary, in particular, if, for example, a web 132 has a profile that could abut the mold surface of a molding tool 200 during demolding and be damaged in the process.

[0041] In further embodiments, the formation of a step in the first area 142 relative to the outer surface 106 can be tolerated, for example, to create a boundary between the first area 142 and the surface 106. Such a step can form an undercut in a molded part 100. Up to a certain depth (e.g., 1 mm) or undercut formation, demolding after the molding process can thus be carried out in a mold without moving parts without damaging the molded part 100.

[0042] As in Fig. 3a ) shown, the material thickness decreases with increasing part height FH (see Fig. 4 ), so that demolding can occur without requiring additional movable mold parts on a mold surface of a mold tool part and without, for example, having to move orthogonally to a mold direction FD. The formation of design elements 130 is created here by increasingly thinner areas.

[0043] Fig. 3b Figure 1 shows a further variant for a design element 130 shaped like a coffee bean, in which elevations are formed along the bridge 132. For this purpose, the design element 130 can be implemented analogously to the execution according to Figure 130. Fig. 3a ) Areas 140 with reduced material thickness, with the material thickness additionally as in Fig. 3a ) can decrease with increasing part height FH.

[0044] Additionally, the material or wall thickness of the web 132 can decrease, or a protrusion 160 can be provided in a sub-area 142 or 144 so that the protrusion 160 does not protrude, or only protrudes slightly, from the overall surface or the surface of a second surface section 122, as for example in Fig. 4 shown schematically.

[0045] Fig. 7Figure 1 shows a schematic representation of the formation of a design element 130 on the surface 106 of a molded part 100 made of fibrous material in a further embodiment, wherein an initial region 146 is provided in front of the partial areas 142, 144 with reduced material thickness, which also has a reduced material thickness. In the illustrated embodiment, the initial region 146 is not part of the design element 130 and serves to provide a minimum reduction in material thickness in the area of ​​the design element 130 so that the design element 130 is clearly distinguishable from the surrounding surface 106 of the molded part 100 and thus visually and / or haptically differentiated.Since there is no homogeneous decrease in material thickness between the initial area 146 and the first sub-area 142, as there is in the remaining area 140, an edge 148 is formed, which provides a clear demarcation between the design element 130 and the remaining surface 106. The initial area 146 is barely perceptible and is perceived as part of the surface design in the second surface section 122 and not as part of the first surface section 120 or the design element 130.

[0046] Fig. 4 shows a schematic representation of a cross-sectional view of a molded part 100 made of fibrous material with differently formed elevations 160 and design elements 130.

[0047] The molded part 100 is like the molded parts 100 made of Fig. 1 and 2The part is shown in an orientation advantageous for manufacturing, with the part height FH determined from the base 102. The individual protrusions 160 are shown on both an outer surface 106 and an inner surface 108 to schematically illustrate the possible positions for protrusions 160. Furthermore, the figure shows Fig. 4 the integration of elevations 160 into transitions 114, where the transitions 114 have a radius that is, for example, in the range of 0.2 to 5 mm. As in Fig. 4As shown on the right side of the molded part 100, a circumferential groove or a local depression is formed in the transition 114, in which a protrusion 160 is integrated, so that the protrusion 160 hardly protrudes from the outside and is therefore neither visually nor haptically perceptible and / or does not impair any function or use. In further embodiments, protrusions 160 can be incorporated in depressions (grooves, craters, etc.), whereby the protrusions 160 do not protrude from the surface of the surrounding second surface sections 122 or only protrude slightly.

[0048] On the right side, the side wall 110 of the molded part 100 has two areas 140 with reduced wall thickness, one area having a web 132 or an analogously designed element on which the protrusions 160 are formed and stand out from the design element 130 (lower example), or the protrusions 160 are arranged in, for example, a sub-area 144 with low material thickness, so that the protrusion 160 does not protrude beyond the surface of the surrounding second surface section 122 (upper example).

[0049] Fig. 5Figure 1 shows schematic representations of the formation of raised areas 160 and design elements 130 on surfaces 106, 108 of a molded part 100. Raised areas 160 can be not only circular, but can also have an elongated and / or curved shape. Polygonal cross-sectional shapes are also possible and can be achieved by appropriately forming openings 234 for steam extraction in the mold surfaces of molding tools 200.

[0050] The elevations 160 can be components of a design element 130 and follow a course of elements (e.g. a bridge 132), or can themselves be a design element, e.g. a letter ("L").

[0051] In further versions, character strings or symbols can also be implemented by several appropriately designed elevations 160, which, for example, give a consumer an indication of use or disposal.

[0052] Fig. 8 shows schematic representations of a molded part 100 with elevations 160, which are in the Fig. 8a) and 8b ) are designed as functional elements 180. The functional elements 180 serve to form an undercut. In the figures, the molded parts 100 are designed as lids, which can, for example, be placed on a cup. In order for the lids to have a secure hold on a cup, for example on a beaded rim of a cup or the like, they have an undercut. In Fig. 8a A side wall 170 is already formed with an inwardly tapered side wall section, which forms an undercut. To reinforce the undercut, the projections 160 are located in this side wall section, so that the projections 160 form functional elements 180 that reinforce the undercut, further reducing the inner diameter and thus improving the holding effect at an edge.

[0053] In Fig. 8a The raised areas 160 are located on an inner side 172 of the side wall 172. The functional elements 180 can be designed as webs with a freely selectable width or as a continuous raised area 160, as is the case, for example, in Fig. 8b ) is shown. Fig. 8b ) shows a molded part 100 designed as a lid with a substantially parallel oriented side wall 170, which has a circumferential protrusion 160 as a functional element 180 (undercut) on the inside 172, wherein the undercut is formed only by the protrusion 160.

[0054] The surveys 160 can, for example, be formed by short or longer sections, as in Fig. 8a ) indicated. Alternatively, a functional element 180 can be formed by a closed elevation 160.

[0055] A forming tool has corresponding openings for the formation of such functional elements 180 or protrusions 160, which are, for example, slots or slot-like openings (for the designs of the Fig. 8 ) can be executed. In further embodiments, only the protrusions 160, which form at least one functional element 180, can provide a steam discharge, so that a molded part 100 cannot have any further protrusions 160.

[0056] In further variations, functional elements can also be provided on an outer surface 174. Functional elements 180 can, in addition to providing undercuts, also serve, for example, to provide linear strips or ribs on a surface of a molded part 100, which have a specific function ("cooling fins", retaining strips, etc.).

[0057] Fig. 6shows a schematic representation of a molding tool 200 for the production of molded parts 100 from fibrous material.

[0058] In the illustrated embodiment, the forming tool 200 comprises a first tool part 210 and a second tool part 230. The first tool part 210 and the second tool part 230 are made of a metal (e.g., aluminum) or a metal alloy suitable for compressing fibrous material at temperatures ranging from 120 to 300 °C and pressures of 0.2 to 300 N / mm². The tool parts 210 and 230 each have a forming surface 212 and 232, respectively, for compressing fibrous material. The forming surfaces 212 and 232 may also have a special surface coating or design to prevent damage to the forming surfaces 212 and 232 due to moisture contained in the fibrous material and steam escaping during compression.

[0059] In the illustrated embodiment, the lower mold part 210 has a heating device 220. In further embodiments, the heating device 220 can extend into an upper mold area and / or include additional heating elements. In still further embodiments, the upper mold part 230 can additionally or alternatively have a heating device with at least one heating element. Heating devices can, for example, include heating elements in the form of electrically controlled heating cartridges, etc.

[0060] Fig. 6Figure 1 shows a single pair of two corresponding tool parts 210, 230. In further embodiments, a mold 200 can have several pairs of tool parts 210, 230, each of which can be reversibly connected to a tool table or plate. This allows several mold parts 100 to be produced simultaneously in a single molding step. In further embodiments, at least one tool table or plate can have a heating device that provides at least basic heating. Additional heating devices 230 can be provided for the pairs of tool parts or for one of the tool parts 210, 230 per pair of tool parts 210, 230.

[0061] In the illustrated embodiment, the lower tool part 210 has a substantially smooth forming surface 212. The forming surface 232 has openings 234 through which the moisture that arises during the compression of fibrous material under high pressure and due to the temperature introduced via at least the tool part 210, and which escapes from the fibrous material in the form of vapor, is discharged. For this purpose, channels 236 extend from the openings 234 through the tool part 230. In the illustrated embodiment, the channels 234 open into a common channel, which is connected via a connection to further devices for discharging the vapor. For example, devices for generating a vacuum can be connected to this, so that the generated vapor is actively extracted.

[0062] In further embodiments, several connections can be provided through which the steam can be discharged from a tool part 230 or 210. In further embodiments, a lower tool part 210 can also have openings 234 and channels 236.

[0063] Due to the openings 234, protrusions 160 form on the inner and / or outer surface 108, 106 of a molded part 100, schematically indicated by the dashed lines, as described above. While the extent and dimensions of the protrusions 160 are relatively small and can be influenced by appropriately dimensioning the openings 234, protrusions 160 are visually and haptically perceptible in previously known designs and molded parts. The already described designs of Figs. 1 to 5The proposed solution for integrating elevations 160 into surface sections 120 and design elements 130 offers the advantage that the elevations 160 visually integrate into the shape of a molded part 100 or a design element 130 and are therefore neither visually nor haptically disturbing.

[0064] The mold 200 shown is simply designed for forming such molded parts 200 and has no moving components on the mold surfaces 212, 231 that are required for integrating the protrusions. Thus, the integration of the protrusion 160 can be easily implemented with the presented mold design.

[0065] To form design elements 130 with areas 140, the mold surface 232 has protrusions 238, for example to create an element 130 on the side wall 110 of a molded part 100, as in Fig. 3shown. In addition, a raised area 160 can be integrated into such an area 140, for which a bulge 238 at the selected location has an opening 234 for extracting steam.

[0066] The formation of the bulges 238 on the mold surfaces 232 enables forming in the mold direction FD without additional moving elements, since the mold surfaces 212, 232 do not form an undercut in the area of ​​the bulges 238. The bulges form mold elements of the mold tool part 230 and project into the mold space defined by the mold surface 232. In further embodiments, mold elements or bulges 238 can be designed such that, for example, areas with reduced material thickness can be formed in mold parts 100, as in Fig. 7 shown.

[0067] The openings 234 shown as an example are located in the embodiment at the position of the form surface 232, which serve for the formation of design elements 130 and / or on first surface sections 120.

[0068] The production of molded parts 100 from a fibrous material includes a step of providing the fibrous material, which, for example, has a moisture content between 50 and 70 wt.%. During pressing, steam is generated, which must be dissipated from the cavity of a mold 200 between the mold surfaces 212 and 232. Since the generation of steam during pressing is crucial, the moisture content, and not the type of material, is the determining factor. Thus, steam dissipation may only be required locally. Therefore, either a wet or a dry process can be used.

[0069] In a so-called wet process, preforms made of a fiber-containing material are first prepared and then compressed under thermal influence. The preforms can be prepared by drawing fibers from an aqueous solution (pulp) and forming three-dimensional preforms that essentially already have the shape of the products to be manufactured. Additionally, additives such as starch, chemical additives, wax, etc., can be added to the pulp to influence the properties of the products (e.g., barrier properties) and their processability. The fibers can be, for example, natural fibers such as cellulose fibers or fibers from a fiber-containing source material (e.g., recycled paper).Since a fibrous pulp containing natural fibers can be used as the starting material for the molded parts 100, the manufactured molded parts 100 can themselves serve as a starting material for the production of molded parts 100 or other products after their use, or can be composted, because they can generally be completely decomposed and do not contain any harmful, environmentally hazardous substances.

[0070] The preforms can be further modified and subjected to a pre-pressing step. Subsequently, the preforms are pressed into three-dimensional molded parts 100 in a mold 200 under pressure and heat.

[0071] Furthermore, the molded parts 100 can be formed from a loose cellulose web (airlaid) or paper which has a sufficient moisture content at least locally.

[0072] After forming in the mold 200, the manufactured parts 100 can be ejected and subsequently subjected to post-treatment in a separate unit or in the same unit. Post-treatment can include, for example, laminating, printing, etc. In other configurations, the manufactured parts 100 can be treated in other ways to achieve specific properties.

[0073] The formation of molded parts 100 can vary depending on the desired shape. Reference symbol list

[0074] 100 Molded part 102 Base 104 Stand ring 106 Outer surface 108 Inner surface 110 Side wall 112 Ring 114 First transition 116 Second transition 120 First surface section 122 Second surface section 130 Design element 132 Web 140 Area 142 First sub-area 144 Second sub-area 146 Starting area 148 Edge 150 Rim 160 Raised 162 Pattern 170 Side wall 172 Inside 174 Outside 180 Functional element 200 Molding tool 210 First tool part 212 Molding surface 220 Heating device 230 Second tool part 232 Molding surface 234 Opening 236 Channel 238 Bulge

Claims

1. Three-dimensional molded part made of fibrous material, produced in a manufacturing process under pressure and thermal influence, wherein a surface of the molded part has at least one design element and / or functional element formed by at least one area with reduced material thickness, wherein the material thickness of the at least one area decreases with increasing molded part height in a molding direction.

2. Molded part according to claim 1, wherein the surface has an orientation inclined relative to a vertical axis of the molded part, such that a cross-sectional area of ​​the molded part increases in the molding direction.

3. Molded part according to claim 1 or 2, wherein the design element and / or the functional element has at least one protrusion formed by fibrous material which, during the manufacture of the molded part, was sucked into a corresponding opening in a mold surface of a molding tool when steam escaping from the fibrous material during compression was removed.

4. Molded part according to claim 3, wherein the at least one protrusion is arranged in a first surface section which has a different configuration compared to an adjacent at least one second surface section, wherein the at least one protrusion is integrated into the configuration of the first surface section.

5. Molded part according to one of claims 1 to 4, wherein the surface, the design element and / or the functional element has protrusions formed by fibrous material which, during the manufacture of the molded part, were drawn into corresponding openings in a mold surface of a molding tool by removing steam which escapes from the fibrous material during compression, and wherein the protrusions form at least one pattern.

6. Molded part according to one of claims 3 to 5, wherein the protrusions are arranged on an outer surface of the molded part and extend away from the outer surface of the molded part.

7. Molded part according to one of claims 3 to 6, wherein at least one projection has a cross-section that is at least partially oval, elongated, polygonal, or round.

8. Molded part according to one of claims 3 to 7, wherein at least one raised section is designed as a design element and / or functional element.

9. Molded part according to any one of claims 1 to 8, wherein the fibrous material comprises at least 50 wt.% vegetable fibers and / or cellulose fibers.

10. Molding tool for producing molded parts from fibrous material according to any one of claims 1 to 9, wherein the molding tool has at least one molding surface for pressing fibrous material into a three-dimensional molded body, wherein the at least one molding surface surrounds a molding space for pressing the fibrous material, and wherein the at least one molding surface has at least one molding element that increasingly projects away from the at least one molding surface in the molding direction.

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