3d shaped packaging product from air-laid blank

Abstract

A 3D-shaped packaging product (20) for cushioning and / or thermal insulation of packaged goods, the 3D-shaped packaging product (20) being formed by hot-pressing an air-laid blank (10) at an average pressure equal to or lower than 200 kPa, the air-laid blank (10) comprising natural fibers at a concentration of at least 70 wt.% of the air-laid blank (10) and a thermoplastic polymer binder at a concentration selected within an interval of 4 wt.% up to 30 wt.% of the air-laid blank (10). The density of the 3D-shaped packaging product (20) is less than four times the density of the air-laid blank (10), and the density of the 3D-shaped packaging product (20) is selected within an interval of 15 kg / m 3 up to 240 kg / m 3 . The 3D-shaped packaging product (20) maintains at least a substantial part of the porosity of the air-laid blank (10) even after hot-pressing, and thus provides excellent impact absorption and damping properties as well as thermal insulation characteristics.

Description

Technical Field

[0001] This embodiment generally relates to products for three-dimensional (3D) packaging, and particularly to such 3D packaging products suitable for cushioning and / or insulation of packaged goods, and methods for producing such 3D packaging products. Background Technology

[0002] With growing awareness of the environment and human-caused climate change, the use of single-use plastic products and containers is increasingly being questioned. However, despite these concerns, their use has grown significantly over the past decade due to new lifestyle and consumption trends. One reason is the increasing global transport of goods requiring protection against shock and / or extreme temperatures. A common way to protect goods is to include cushioning and / or insulating elements or products, such as inserts of suitable form, in the packaging. These can be made from various materials, but are often made from expanded polystyrene (EPS), the cheapest and most common. In some cases, the entire package can be made of EPS. One example is shipping boxes for food that must be kept within a specified temperature range, such as cold foods (e.g., fish) or hot foods (e.g., ready-to-eat meals). However, EPS is one of the most questioned plastic materials, and many brand owners are looking for more sustainable solutions for these packaging applications. The increasing pressure to find alternatives is also fueled by legislation in many countries targeting single-use plastic products and containers.

[0003] More sustainable polymer product alternatives exist, such as inserts manufactured using a process called pulp molding, in which a fiber suspension is vacuum-adhered to a wire mesh mold. Another technique for forming such inserts is described in U.S. Patent Application No. 2010 / 0190020, European Patent No. 1 446 286, and International Application No. 2014 / 142714, which involve hot-pressing porous fiber mats, produced by a process called air-laying, into a 3D structure using a matching rigid mold or through film molding.

[0004] However, the methods described above provide limited impact protection and insulation. Therefore, there is a market demand for 3D-shaped packaging products that can be manufactured using materials more environmentally friendly than EPS for cushioning and / or insulation of packaged goods. Summary of the Invention

[0005] The object of the present invention is to provide 3D-shaped packaging products for cushioning and / or heat insulation of packaged goods, and a method for producing such 3D-shaped packaging products.

[0006] The specific purpose is to provide this 3D-shaped packaging product that can be made from natural fibers.

[0007] The embodiments of the present invention satisfy these and other objectives.

[0008] This invention is defined in the independent claims. Further embodiments of this invention are defined in the dependent claims.

[0009] One aspect of the invention relates to a 3D-shaped packaging product for cushioning and / or insulation of packaged goods. The 3D-shaped packaging product is formed by hot-pressing an air-laid blank at an average pressure equal to or below 200 kPa. The air-laid blank comprises at least 70% by weight of natural fibers and a thermoplastic polymer binder selected from 4% to 30% by weight of the air-laid blank. The density of the 3D-shaped packaging product is less than four times the density of the air-laid blank, and the density of the 3D-shaped packaging product is 15 kg / m³. 3 Up to 240kg / m 3 Choose within the specified range.

[0010] Another aspect of the invention relates to a method of manufacturing a 3D-shaped packaging product for cushioning and / or insulating packaged goods. The method includes hot-pressing a male tool into an air-laid preform at an average pressure equal to or less than 200 kPa to form a 3D-shaped packaging product having a 3D shape at least partially defined by the male tool. The air-laid preform comprises at least 70% by weight of natural fibers and a thermoplastic polymer binder selected from the range of 4% to 30% by weight of the air-laid preform. The density of the 3D-shaped packaging product is less than four times the density of the air-laid preform, and the density of the 3D-shaped packaging product is 15 kg / m³. 3 Up to 240kg / m 3 Choose within the specified range.

[0011] This invention relates to 3D-shaped packaging products that retain at least a majority of the porosity of the air-laid preform even after hot pressing. This means that the 3D-shaped packaging products are highly suitable for cushioning packaged goods, providing excellent shock absorbing and damping properties. The porosity of these 3D-shaped packaging products also imparts thermal insulation properties, and therefore they can be used for storing and / or transporting tempered (e.g., cold or hot) goods, such as supplies and food. The 3D-shaped packaging products suitable for cushioning and / or thermal protection are also made from environmentally friendly natural fibers, in stark contrast to prior art foam inserts made of polystyrene and other polymers. Attached Figure Description

[0012] The embodiments and their further objects and advantages can be best understood by referring to the following description in conjunction with the accompanying drawings, wherein:

[0013] Figure 1 This is an illustrative embodiment of the cross-section of a 3D-shaped packaged product;

[0014] Figure 2 schematically shown Figure 1 The 3D-shaped packaging product in which different parts of the 3D packaging product have different densities;

[0015] Figure 3 This schematically illustrates the hot pressing of the airflow to lay the blank to form Figure 1 The 3D-shaped packaging product shown is before the punch is joined with the airflow layup blank to create a cavity;

[0016] Figure 4 This schematically illustrates the hot pressing of the airflow to lay the blank to form Figure 1 The 3D-shaped packaging product shown is in the process of joining the punch with the air-laid blank;

[0017] Figure 5 A punch and a die are schematically shown configured for hot-pressed airflow to lay up a blank to form a 3D-shaped packaged product according to one embodiment.

[0018] Figure 6 These are illustrations and close-ups of punches that can be used for hot pressing and cutting airflow-layout blanks to form 3D-shaped packaged products;

[0019] Figure 7 This is a flowchart illustrating a method for manufacturing a 3D-shaped packaging product for cushioning and / or insulating goods according to one embodiment; and

[0020] Figure 8 It shows Figure 7A flowchart of additional optional steps in the method shown. Detailed Implementation

[0021] This embodiment generally relates to three-dimensional (3D) packaging products, and more specifically to such 3D packaging products suitable for cushioning and / or insulation of packaged goods, and methods for producing such 3D packaging products.

[0022] The 3D-shaped packaging product of this embodiment can be used as a more environmentally friendly alternative to corresponding 3D-shaped packaging products made of foamed polymers (e.g., expanded polystyrene (EPS)). More sustainable alternatives to polymer products have been proposed in U.S. Patent Application No. 2010 / 0190020, European Patent No. 1446 286, and International Application No. 2014 / 142714. These patents involve hot-pressing porous fiber mats (pads) produced by a process called airflow layup into 3D structures using a matching rigid mold or by film molding. However, the 3D-shaped packaging products produced in the aforementioned documents are dense, have a thin cross-section, and therefore have limited shock absorption or damping capabilities and relatively poor thermal insulation.

[0023] The 3D-shaped packaging product of this embodiment is formed by hot-pressing an air-laid preform containing natural fibers and a binder. An air-laid preform, sometimes also called a dry-laid preform, air-laid mat, dry-laid web, or dry-laid web, is formed by a process called air-laying, in which natural fibers and a binder are mixed with air to form a porous fiber mixture deposited onto a carrier and solidified or bonded by heating or thermoforming. This air-laid preform is characterized by being porous, having the characteristics of open-cell foam, and being produced by a so-called dry-forming method, i.e., typically without the addition of water. The air-laid process was originally described in U.S. Patent No. 3,575,749. An air-laid preform may be in the form produced in the air-laid process. Alternatively, the air-laid preform may be in a form that is at least partially processed, for example, by cutting into a given shape before hot pressing.

[0024] Unlike U.S. Patent Application No. 2010 / 0190020, European Patent No. 1 446 286, and International Application No. 2014 / 142714, the 3D-shaped packaging product of this embodiment, formed from an air-laid preform, retains the characteristics of the air-laid preform even after hot pressing, and therefore exhibits excellent shock absorption and thermal insulation properties. Thus, the 3D packaging product can be manufactured with a geometry suitable for protecting goods during transport and / or storage, i.e., a 3D shape. Maintaining the porous nature of the air-laid preform raw material means that this 3D-shaped packaging product can be used not only to protect consumer goods and products, but also to protect heavy equipment from impacts. Furthermore, compared to compact and dense 3D-shaped packaging products with thin cross-sections, the porous 3D-shaped packaging product of this embodiment has improved thermal insulation properties. This means that the 3D-shaped packaging product can also, or alternatively, be used for storing and / or transporting goods that need to be kept refrigerated (e.g., cold provision, refrigerated food) or goods that need to be kept hot or warm (e.g., ready-to-eat meals).

[0025] One aspect of the invention relates to a 3D-shaped packaging product 20 for cushioning and / or insulating packaged goods, see [link to product description]. Figure 1 The 3D-shaped packaging product 20 is formed by hot-pressing the preform 10 under an average pressure equal to or below 200 kPa. See [reference needed]. Figure 3 and Figure 4 The air-laid preform 10 comprises at least 70% by weight of natural fibers and a thermoplastic polymer binder with a concentration ranging from 4% by weight to a maximum of 30% by weight of the air-laid preform 10. The density of the 3D packaged product 20 is less than four times the density of the air-laid preform 10, and the density of the 3D packaged product 20 is 15 kg / m³. 3 Up to 240kg / m 3 Choose within the specified range.

[0026] The 3D packaging product 20 of this embodiment is formed from an air-laid preform 10 in a hot-pressing process that retains at least some porosity of the air-laid preform 10. Therefore, the density of the 3D packaging product 20 is less than four times the density of the air-laid preform 10. Existing hot-pressing processes for producing dense 3D packaging products with thin cross-sections typically increase the density of the 3D packaging product by tens of times (e.g., 10 to 50 times) the density of the air-laid preform. This significant increase in density in existing 3D packaging products means a significant loss of porosity in the air-laid preform, resulting in a dense and compact fibrous structure. In stark contrast, the density increase according to the invention is relatively low, and the porous structure of the air-laid preform 10 is also maintained in the formed 3D packaging product 20.

[0027] The 3D-shaped products disclosed in the aforementioned U.S., European, and international applications are produced by subjecting an air-laid preform to high pressure: at least 1 MPa, for example, from 1 MPa to 200 MPa, preferably exceeding 20 MPa, as disclosed in International Application No. 2014 / 142714. The high pressure used in the prior art forcefully compresses the air-laid preform, thereby obtaining a pressure of 500 kg / m³. 3 Up to 1000 kg / m 3 Especially 800kg / m 3 The above describes relatively high-density 3D-shaped products. This high density makes existing 3D-shaped products unsuitable for cushioning packaged goods and for storage, and also unsuitable for transporting formulated goods.

[0028] In this implementation, the average pressure is defined as the force applied during hot pressing divided by the area of ​​the airflow-laid blank 10.

[0029] As used herein, the density of the 3D-shaped packaging product 20 is the average or mean density of the 3D-shaped packaging product 20. This means that the 3D-shaped packaging product 20 may contain portions 25A, 25B, 25C, 25D, 25E ​​with different porosities and thus different densities, see [reference]. Figure 2 This is because the shape of the punch 30 used in the hot pressing process results in different portions of the blank 10 being laid with varying degrees or amounts of hot press airflow, see [link to relevant documentation]. Figure 3 and 4 The different densities in different portions (25A, 25B, 25C, 25D, 25E) of the 3D packaged product 20 Figure 2 The diagram is schematically illustrated using different grayscale patterns. For example, the portion of the air-laid preform 10 aligned with the protruding structure 32 of the punch 30 will be pressed and compressed more forcefully compared to other portions of the air-laid preform 10. Therefore, portions 25C and 25E of the 3D packaged product 20 aligned with the protruding structure 32 of the punch 30 will have a higher density compared to other portions 25A, 25B, and 25D of the 3D packaged product. However, the density of the 3D packaged product 20 is an average or intermediate density, not the density of its different portions, and represents the total mass of the 3D packaged product 20 divided by the volume of the 3D packaged product 20 (excluding any cavities 26 formed by the punch 30 (possibly combined with the die 50) during hot pressing), see [link to relevant documentation]. Figure 5 .

[0030] As used herein, hot pressing refers to the process whereby the air-laid preform 10 is exposed to pressure applied by pressing a punch 30 or a combination of a punch 30 and a die 50 into the air-laid preform 10 while it is being heated or exposed to heat. Therefore, hot pressing implies pressing at a temperature above room temperature, preferably at a temperature at which the thermoplastic polymer adhesive or at least a portion thereof is malleable. In this context, hot pressing is used in conjunction with... Figure 7 and Figure 8 Hot pressing of blank 10 using heated tools 30, 50 and / or heated airflow is further described.

[0031] In one embodiment, the density of the 3D-shaped packaging product 20 is equal to or less than three times the density of the air-laid preform 10. In a particular embodiment, the density of the 3D-shaped packaging product 20 is equal to or less than twice the density of the air-laid preform 10.

[0032] Therefore, according to the present invention, the hot pressing of the air-laid preform 10 results in an increase in the density of the 3D packaged product 20 by no more than 300%, preferably no more than 250%, more preferably no more than 200%, 150%, or most preferably no more than 100% compared to the density of the air-laid preform 10.

[0033] However, since the punch 30 or both the punch 30 and the die 50 are hot-pressed into the air-laid preform 10, the hot pressing preferably results in an increase in the density of the 3D packaged product 20 compared to the density of the air-laid preform 10. The increase in density caused by hot pressing is preferably at least 10%, for example at least 12.5%, at least 15%, at least 17.5%, at least 20%, at least 22.5%, at least 25%, or even higher, for example at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, or at least 100%.

[0034] In each embodiment, the increase in density caused by hot pressing is at least 12.5% ​​but not more than 300%, for example at least 15% but not more than 275%, at least 17.5% but not more than 250%, at least 20% but not more than 225%, for example at least 22.5% but not more than 200%.

[0035] In a particular embodiment, no part of the 3D-shaped packaging product 20 formed by hot-pressed airflow layup of the preform 10 has a high density. Therefore, cushioning and / or thermal insulation properties are preferably achieved for all parts of the 3D-shaped packaging product 20. In this embodiment, the density of any part of the 3D-shaped packaging product 20 does not exceed ten times the average density of the airflow-laid preform 10, preferably not more than nine times, for example not more than eight, seven, six, or five times, more preferably not more than four times, for example not more than three or two times.

[0036] In this embodiment, the density of the air-laid blank 10 is 10 kg / m³. 3 Up to 60kg / m 3 Choose within the specified range.

[0037] According to the present invention, the density of the 3D-shaped packaged product 20 is 15 kg / m³. 3 Up to 240kg / m 3 The density of the 3D-shaped packaged product 20 is selected within the specified range. In a preferred embodiment, the density of the 3D-shaped packaged product 20 is 15 kg / m³. 3 Up to 200kg / m 3 Within the specified range, 15 kg / m³ is preferred. 3 Up to 150kg / m 3 Within the range, it is more preferable to be within 15 kg / m 3 Up to 100kg / m 3 The density is selected within the specified range. In a particular embodiment, the density of the 3D-shaped packaged product 20 is 20 kg / m³. 3 Up to 75kg / m 3 Within the specified range, the preferred value is 25 kg / m³. 3 Up to 70kg / m 3 Within the range, it is more preferable to be within 25 kg / m 3 Up to 65kg / m 3 Choose within the specified range.

[0038] In one embodiment, the natural fiber is a lignocellulose fiber. In a particular embodiment, the natural fiber is a cellulose and / or lignocellulose fiber. Thus, in one embodiment, the natural fiber contains cellulose, for example in the form of cellulose and / or lignocellulose (i.e., a mixture of cellulose and lignin). The natural fiber may also contain lignin, for example in the form of lignocellulose. The natural fiber may also contain hemicellulose. In a particular embodiment, the natural fiber is a cellulose and / or lignocellulose pulp fiber produced by chemical, mechanical, and / or chemimechanical pulping of softwood and / or hardwood. For example, the cellulose and / or lignocellulose pulp fiber is selected from the following forms: sulfate pulp, sulfite pulp, thermomechanical pulp (TMP), high-temperature thermomechanical pulp (HTMP), mechanical fiber (MDF-fiber) intended for use in medium-density fiberboard, chemimechanical pulp (CTMP), high-temperature chemimechanical pulp (HTCTMP), and combinations thereof.

[0039] This natural fiber can also be produced by other pulping methods and / or from other cellulose or lignocellulose raw materials (e.g., flax, jute, hemp, kenaf, bagasse, cotton, bamboo, straw, or rice husk).

[0040] The air-laid preform 10 comprises natural fibers at a concentration of at least 70% by weight of the preform 10. In a preferred embodiment, the air-laid preform 10 comprises natural fibers at a concentration of at least 72.5% by weight, more preferably at least 75% by weight, such as at least 77.5% by weight, at least 80% by weight, at least 82.5% by weight, or at least 85% by weight of the preform 10. In some applications, even higher concentrations of natural fibers may be used, such as at least 87.5% by weight, or at least 90% by weight, at least 92.5% by weight, at least 95% by weight, or at least 96% by weight of the preform 10.

[0041] A thermoplastic polymer binder is included in the air-laid preform 10 as an adhesive to bond the air-laid preform 10 together and protect its form and structure during use, handling, and storage. The thermoplastic polymer binder also helps to form a foam-like structure of the air-laid preform 10. The thermoplastic polymer binder is mixed with natural fibers during the air-laying process to form a fiber mixture. The thermoplastic polymer binder can be added in powder form, but more often it is added in the form of fibers mixed with natural fibers during the air-laying process. Alternatively or otherwise, the thermoplastic polymer binder can be added to and onto the air-laid preform 10 as a solution, emulsion, or dispersion during the air-laying process. The latter technique is best suited for thin air-laid preforms 10.

[0042] In a particular embodiment, the thermoplastic polymer binder is selected from thermoplastic polymer powder, thermoplastic polymer fiber, and combinations thereof.

[0043] In this embodiment, the softening point of the thermoplastic polymer adhesive or at least a portion thereof does not exceed the degradation temperature of the natural fibers. Therefore, the thermoplastic polymer adhesive or at least a portion thereof softens at a processing temperature during hot pressing that does not exceed the degradation temperature of the natural fibers. This means that at least a portion of the thermoplastic polymer adhesive becomes stretchable but preferably non-melting, enabling hot pressing while at least partially maintaining the porous structure of the air-laid preform 10 in the 3D packaged product 20, and wherein the hot pressing is performed at a temperature that does not degrade the natural fibers in the air-laid preform 10.

[0044] In embodiments, the thermoplastic polymer binder is or comprises thermoplastic polymer fibers cut to a fixed length, commonly referred to as short fibers. It is generally preferred for the performance of the air-laid preform 10 formed by mixing the thermoplastic polymer fibers with or longer than the natural fibers during the air-layout process. The lengths of the thermoplastic polymer fibers and natural fibers referred to herein are length-weighted average fiber lengths. The length-weighted average fiber length is calculated by dividing the sum of the squares of the individual fiber lengths by the sum of the individual fiber lengths.

[0045] In one embodiment, the thermoplastic polymer adhesive is or comprises thermoplastic polymer fibers whose length-weighted average fiber length is selected within the range of 100% to 600% of the length-weighted average fiber length of the natural fiber, preferably 125% to 500%, and more preferably 150% to 450%. In a particular embodiment, the thermoplastic polymer adhesive is or comprises thermoplastic polymer fibers whose length-weighted average fiber length is selected within the range of 200% to 400% of the length-weighted average fiber length of the natural fiber, preferably within the range of 250% to 350%. In a particular embodiment, the length-weighted average fiber length of the thermoplastic polymer fibers is in the range of 1 mm to 12 mm, for example, in the range of 1 mm to 10 mm, preferably in the range of 2 mm to 8 mm, and more preferably in the range of 2 mm to 6 mm.

[0046] The length-weighted average fiber length of natural fibers depends on the source of the natural fibers (e.g., the tree species from which they originate) and the pulping process. The typical range of length-weighted average fiber length for wood pulp fibers is about 0.8 mm, with a maximum of about 5 mm.

[0047] In embodiments, the thermoplastic polymer adhesive is or comprises single-component and / or bicomponent thermoplastic polymer fibers. Bicomponent thermoplastic polymer fibers (also known as bico fibers) comprise a core structure and a sheath structure, wherein the core is made of a first polymer, copolymer, and / or polymer mixture, and the sheath is made of a different second polymer, copolymer, and / or polymer mixture.

[0048] In embodiments, the thermoplastic polymer binder is or comprises, such as, a bicomponent polymer fiber comprising a core component made of a material having a melt temperature higher than the temperature at which the air-laid preform 10 is heated during hot pressing. The bicomponent polymer fiber also comprises a sheath component made of a material having a melt temperature lower than the temperature at which the air-laid preform 10 is heated during hot pressing.

[0049] In this embodiment, the melt temperature of the core component of the bicomponent polymer fiber is higher than the melt temperature of the sheath component. Furthermore, the melt temperature of the core component is higher than the processing temperature at which the air-laid preform is heated during hot pressing, while the melt temperature of the sheath component is lower. This means that the core component will not melt during hot pressing but will advantageously become stretchable, while the sheath component will melt or at least significantly thicken. Thus, the sheath component will adhere to the natural fibers, while the unmelted but stretchable core component provides structural support. This bicomponent polymer fiber achieves good adhesion to natural fibers while maintaining the porous structure of the air-laid preform even during hot pressing.

[0050] In an embodiment, the thermoplastic polymer adhesive is or comprises the following, such as being composed of the following: a single-component thermoplastic polymer fiber made of the following materials: i) selected from polyethylene (PE), ethylene acrylate copolymer (EAA), ethylene-vinyl acetate (EVA), polypropylene (PP), polystyrene (PS), polybutylene terephthalate (PBAT), polybutylene succinate (PBS), polylactic acid (PLA), polyethylene terephthalate (PET), polycaprolactone (PCL), copolymers thereof, and mixtures thereof, and ii) optionally one or more additives.

[0051] Therefore, in one embodiment, the thermoplastic polymer fiber is made of materials selected from the group above. In another embodiment, the thermoplastic polymer fiber is made of materials selected from the group above, plus one or more additives.

[0052] In another embodiment, the thermoplastic polymer adhesive is or comprises the following, such as being composed of: a bicomponent thermoplastic polymer fiber having a core and / or sheath made of: i) one or more materials selected from PE, EAA, EVA, PP, PS, PBAT, PBS, PLA, PET, PCL, copolymers thereof, and mixtures thereof, and ii) optionally one or more additives. In another embodiment, the thermoplastic polymer adhesive is or comprises, such as being composed of: a combination or mixture of a single-component thermoplastic polymer fiber and a two-component thermoplastic polymer fiber, wherein the single-component thermoplastic polymer fiber is made of: i) a material selected from PE, EAA, EVA, PP, PS, PBAT, PBS, PLA, PET, PCL, copolymers thereof and mixtures thereof, and ii) optionally one or more additives, wherein the two-component thermoplastic polymer fiber has a core and / or sheath made of: i) one or more materials selected from PE, EAA, EVA, PP, PS, PBAT, PBS, PLA, PET, PCL, copolymers thereof and mixtures thereof, and ii) optionally one or more additives.

[0053] The thermoplastic polymer adhesive can be made from a single type of thermoplastic polymer fiber, i.e., from the same material (in the case of single-component thermoplastic polymer fibers), or from one or more of the same materials (in the case of two-component thermoplastic polymer fibers). However, it is also possible to use a thermoplastic polymer adhesive made from one or more (i.e., two or more) different single-component thermoplastic polymer fibers made from different materials and / or one or more different two-component thermoplastic polymer fibers made from different materials.

[0054] In embodiments, the thermoplastic polymer binder is or comprises a thermoplastic polymer powder made of: i) a material selected from PE, EAA, EVA, PP, PS, PBAT, PBS, PLA, PET, PCL, copolymers thereof, and mixtures thereof, and ii) optionally one or more additives.

[0055] As mentioned above, thermoplastic polymer adhesives, which are combinations of thermoplastic polymer fibers and thermoplastic polymer powders, can also be used.

[0056] According to this embodiment, specific examples of materials that can be used for thermoplastic polymer adhesives include PBAT, PBS, PLA, PCL, copolymers thereof, and mixtures thereof. In this case, thermoplastic polymer adhesives made from these materials are suitable for use as compost under industrial conditions.

[0057] Typically, air-laid preforms and 3D-shaped packaging products made from them can be recycled if they can disintegrate in an opener for this specific purpose and can be passed through the air-laid process again, possibly with the addition of additional adhesives. In practice, this only applies to edge trimmings and other process waste recycled internally within the production facility. This is not an option for consumers and other end-users, as the air-laid process is not present in existing recycling schemes. A better option would be if products produced by air-laid, or products made from air-laid, could be sorted into one of the existing recycling fractions in an existing, operating collection and recycling system. Since most of the material is made from wood fibers that can enter the paper or paperboard manufacturing process, these materials would be a naturally occurring fraction for collecting air-laid preforms and 3D-shaped packaging products. Paperboard fractions are generally a better option where printing paper is sensitive to impurities that can cause defects in the printing process or a darkening of the paper. Recycled paperboard is often used as the middle layer of boxboard with several layers, or as the groove in corrugated cardboard. These are less sensitive to impurities (even those that reduce the strength of recycled materials).

[0058] A prerequisite for a material to be recycled as board material is that it is repulpable, meaning that when sheared with water in a repulping process, most of it will break down into individual fibers, thus yielding a usable pulp with good yields after subsequent screening. Conventional thermoplastic binders used for air-laid preforms adhere too well to cellulose and / or lignocellulose fibers. Therefore, these thermoplastic polymer binders hinder disintegration to the extent that the yield of the repulping process is too low to be economically viable.

[0059] Thermoplastic polymers with high viscosity and low melting points, typically used for sheaths of monocomponent and bicomponent fibers, present additional problems in paperboard recycling. These materials become sticky, rendering them unsuitable for recycling in repulping processes. One approach to addressing these issues is to use adhesives that are water-soluble in the repulping process—that is, water-soluble at repulping temperatures. Simultaneously, the adhesive needs to be thermoplastic, with a melting point not exceeding the degradation temperature of the natural fibers, and should maintain excellent adhesion to natural fibers after reheating and cooling. Furthermore, the adhesive should not have harmful effects on the paperboard manufacturing process. It is also advantageous if their use in food contact applications is safe.

[0060] In paper or paperboard processes, "repulpability" and "recyclability" are most widely tested using the PTS method PTS-RH 021 / 97 from the German Papiertechnische Stiftung. For paperboard products, the PTS method tests recyclability in two steps, the first of which is a repulpability test. In the repulpability test, 50g of material is disintegrated in a standard disintegrator under the conditions specified in PTS method PTS-RH 021 / 97 for 20 minutes. Undispersed residue is screened out and its weight is determined. If the weight of the undispersed residue corresponds to less than 20% of the original weight (50g), the material is classified as "recyclable." If the weight of the undispersed residue is 20-50% of the original weight, the material is classified as "recyclable but worthy of product design improvement." Part II of PTS Method PTS-RH 021 / 97 for paperboard products tests for impurities, particularly substances that become extremely sticky when heated to 130°C during the test. In paperboard manufacturing, such sticky or viscous substances can adhere to machine fabrics and other essential components of the board-making machine, causing operational problems and requiring lengthy and costly downtime for cleaning. In the paper and paperboard industry, this type of impurity is commonly referred to as "adhesive." The presence of such adhesive in an unscreened, disintegrated sample classifies the material as "non-recyclable due to adhesive." The presence of other impurities limits the availability of recycled pulp from the material but is not considered entirely harmful.

[0061] Therefore, in embodiments, the thermoplastic polymer adhesive, or at least a portion thereof, is water-soluble at the repulping temperature selected for the repulping of the 3D packaging product 20. In this case, the 3D packaging product 20 can be recycled in the repulping process described above. Water solubility as used herein means that the thermoplastic polymer adhesive can be dissolved or dispersed in water during the repulping process. For example, the thermoplastic polymer adhesive can be dissolved or dispersed in water at the repulping temperature of the repulping process, i.e., forming a solution or colloidal dispersion, wherein the thermoplastic polymer adhesive exists as a monomolecule and / or forms colloidal aggregates. In embodiments, water solubility as used herein means a solubility greater than 0.5 g thermoplastic polymer adhesive / 100 ml water, preferably at least 1 g thermoplastic polymer adhesive / 100 ml water, more preferably at least 5 g thermoplastic polymer adhesive / 100 ml water, for example at least 10 g thermoplastic polymer adhesive / 100 ml water. Therefore, in embodiments, at least a portion of the water-soluble thermoplastic polymer adhesive preferably has water solubility according to the above description.

[0062] Examples of such water-soluble thermoplastic polymer adhesives are made from single-component and / or two-component thermoplastic polymer fibers: i) materials selected from polyvinyl alcohol (PVA), polyethylene glycol (PEG), poly(2-ethyl-2-oxazoline) (PEOX), polyvinyl ether (PVE), polyvinylpyrrolidone (PVP), polyacrylic acid (PAA), polymethacrylic acid (PMAA), copolymers thereof, and mixtures thereof, and ii) optionally one or more additives.

[0063] In one embodiment, the thermoplastic polymer adhesive is or comprises, for example, a single-component thermoplastic polymer fiber made of: i) a material selected from PVA, PEG, PEOX, PVE, PVP, PAA, PMAA, copolymers thereof, and mixtures thereof, and ii) optionally one or more additives. In another embodiment, the thermoplastic polymer adhesive is or comprises, for example, a two-component thermoplastic polymer fiber having a sheath or sheath and core made of: i) a material selected from PVA, PEG, PEOX, PVE, PVP, PAA, PMAA, copolymers thereof, and mixtures thereof, and ii) optionally one or more additives. In a particular embodiment, at least the sheath of the two-component thermoplastic polymer fiber is made of: i) a material selected from PVA, PEG, PEOX, PVE, PVP, PAA, PMAA, copolymers thereof, and mixtures thereof, and ii) optionally one or more additives. In such a particular embodiment, the material of the core of the two-component thermoplastic polymer fiber may also be selected from this group. However, if the core of the bicomponent thermoplastic polymer fiber does not soften during hot pressing and becomes sticky and adheres to the natural fiber, then the core can actually be made of a material that does not need to be water-soluble at the repulping temperature. This means that the core can be made of the aforementioned thermoplastic polymer material. Therefore, in this particular embodiment, the bicomponent thermoplastic polymer fiber comprises a core component and a sheath component, the core component being made of: i) a material selected from polyethylene (PE), EAA, EVA, PP, PS, PBAT, PBS, PLA, PET, PCL, copolymers thereof, and mixtures thereof, and ii) optionally one or more additives, and the sheath component being made of: i) a material selected from PVA, PEG, PEOX, PVE, PVP, PAA, PMAA, copolymers thereof, and mixtures thereof, and ii) optionally one or more additives. In another embodiment, the thermoplastic polymer adhesive is or comprises, such as a combination of a single-component thermoplastic polymer fiber and a two-component thermoplastic polymer fiber, wherein the single-component thermoplastic polymer fiber is made of: i) a material selected from PVA, PEG, PEOX, PVE, PVP, PAA, PMAA, copolymers thereof and mixtures thereof, and ii) optionally one or more additives, and the two-component thermoplastic polymer fiber has a core and / or sheath made of: i) one or more materials selected from PVA, PEG, PEOX, PVE, PVP, PAA, PMAA, copolymers thereof and mixtures thereof, and ii) optionally one or more additives.

[0064] In embodiments, the thermoplastic polymer binder is or comprises a thermoplastic polymer powder made from: i) a material selected from PVA, PEG, PEOX, PVE, PVP, PAA, PMAA, copolymers thereof, and mixtures thereof, and ii) optionally one or more additives.

[0065] In a particular embodiment, the air-laid preform 10 and preferably the 3D packaged product 20 are repulped or recyclable, preferably as defined by the PTS method PTS-RH 021 / 97 from the German Papiertechnische Stiftung. Therefore, in a particular embodiment, after disintegrating 50g of the air-laid preform 10 or the 3D packaged product 20 in a standard disintegrator for 20 minutes under the conditions specified in the PTS method PTS-RH 021 / 97, the air-laid preform 10 and preferably the 3D packaged product 20 produce less than 50% (w / w), preferably less than 20% (w / w) of undispersed residue.

[0066] The repulping temperature used in the repulping process is typically in the range of 20°C to 100°C, for example, in the range of 30°C to 90°C, and generally in the range of 30°C to 70°C. Therefore, in embodiments, at least a portion of the thermoplastic polymer adhesive is water-soluble at a temperature selected within the range of 20°C to 100°C, preferably within the range of 30°C to 90°C, and more preferably within the range of 30°C to 70°C. In a particular embodiment, according to the PTS method PTS-RH 021 / 97, the temperature of the water used in the repulping process is approximately 40°C. Therefore, in embodiments, at least a portion of the thermoplastic polymer adhesive is water-soluble at 40°C.

[0067] More specifically, the PTS method, PTS-RH 021 / 97, involves disintegrating the sample according to DIN EN ISO 5263-1:2004-12, but using tap water at 40°C. Diluent is poured onto the sample material, which is then placed in a disintegrator (the standard disintegrator according to DIN EN ISO 5263-1:2004-12) without pre-swelling. The sample material is disintegrated to a consistency of 2.5% od, equivalent to a weighing of 50 og.d. and a slurry volume of 2 l. The disintegration time is 20 minutes (60,000 rpm). After disintegration, the slurry (total raw material) is completely transferred to a standard distributor (the standard distributor in ZELLCHEMING Technical Information Sheet ZM V / 6 / 61) and diluted with tap water to a total volume of 10 l, corresponding to a consistency of 0.5%. According to ZELLCHEMING Technical Information Sheet ZM V / 18 / 62, a porous plate with a pore size of 0.7 mm was used for screening. The test equipment was set to "low stroke" mode. A test portion corresponding to 2 g od (400 ml) of slurry was removed from the dispenser and diluted to a total volume of 1000 ml. This was then filled into the classifier within 30 seconds and screened for 5 minutes at a wash water pressure of 0.3 bar. After 5 minutes, the water supply and membrane displacement motor were shut off. The valve on the retaining ring was opened to drain the water that had accumulated below the test chamber. The locking screw was loosened, and the test chamber was tilted upwards. One hand was placed over the rear nozzle to prevent water droplets from falling onto the unprotected porous plate with residue on it. The residue from the porous plate was washed into a 2 L tank and dewatered through a filter (membrane) inserted into a Buchner funnel. The filter was folded once and placed in a desiccator to dry at 105°C to a maximum weight constant. If the disintegration residue does not exceed 20% of the input amount, the product is rated as "recyclable"; if the disintegration residue is between 20% and 50% of the input amount, the product is rated as "recyclable but worthy of product design improvement".

[0068] In one embodiment, the air-laid preform 10 comprises a thermoplastic polymer binder at a concentration ranging from 10% by weight to 30% by weight of the air-laid preform 10, for example, selected from 15% by weight to 30% by weight. In a particular embodiment, the air-laid preform 10 comprises more than 15% by weight but not more than 30% by weight of the thermoplastic polymer binder. For example, the air-laid preform 10 comprises a thermoplastic polymer binder at a concentration ranging from 15% by weight or 17.5% by weight to 30% by weight of the air-laid preform 10. In a particular embodiment, the air-laid preform 10 comprises a thermoplastic polymer binder at a concentration ranging from 15% by weight or 17.5% by weight to 25% by weight of the air-laid preform 10, for example, selected from 20% by weight to 25% by weight.

[0069] In some applications, a relatively high concentration of thermoplastic polymer binder can be advantageous, for example, greater than 15% by weight of the air-laid preform 10, so as to maintain the integrity and foam structure of the air-laid preform 10 even when hot-pressing the air-laid preform 10 at lower pressures to obtain a porous 3D package product 20. Therefore, if too low a concentration of thermoplastic polymer binder is included, i.e., less than 4% by weight of the air-laid preform 10, the resulting 3D package product 20 may unintentionally disintegrate or collapse, because the combination of such a low concentration of thermoplastic polymer binder with the “soft” hot pressing of the air-laid preform 10 is insufficient to maintain the structure of the 3D package product 20.

[0070] In some embodiments, the air-laid preform 10 comprises a thermoplastic polymer binder at a concentration ranging from 4% to 15% by weight of the air-laid preform 10, preferably from 5% to 15% by weight, or from 7.5% to 15% by weight, more preferably from 10% to 15% by weight. These embodiments are particularly suitable for use with thermoplastic polymer binders that are water-soluble at the repulping temperature selected for the repulped 3D packaging product, for example, suitable for use with thermoplastic polymer fibers made from: i) one or more materials selected from PVA, PEG, PEOX, PVE, PVP, PAA, PMAA and their copolymer mixtures, and ii) optionally one or more additives.

[0071] In this embodiment, the thickness of the air-laid preform 10 is at least 20 mm, preferably at least 30 mm, more preferably at least 40 mm, or even thicker, such as at least 50 mm, at least 60 mm, at least 70 mm, at least 80 mm, or at least 90 mm. In a particular embodiment, the thickness of the air-laid preform 10 is at least 100 mm, such as at least 150 mm, at least 200 mm, or at least 250 mm. Very thick air-laid preforms 10, with a thickness of at least 300 mm, are also possible. Therefore, this embodiment preferably uses a relatively thick air-laid preform 10 to produce 3D-shaped packaging products 20 that are suitable for cushioning and / or insulation even after hot pressing. The thickness of the air-laid preform 10 can be selected based on the specific application of the resulting 3D-shaped packaging product 20, such as based on the cushioning and / or insulation requirements of the 3D-shaped packaging product 20, and / or based on the geometry of the packaged goods to be protected by the 3D-shaped packaging product 20.

[0072] Accordingly, the thickness of the 3D packaged product 20 may be at least 10 mm, preferably at least 15 mm, for example at least 20 mm or at least 25 mm, more preferably at least 30 mm, for example at least 35 mm, or at least 40 mm, or even thicker, for example at least 45 mm or at least 50 mm. According to the invention, when the air-laid preform 10 is hot-pressed into the 3D packaged product 20, a low average pressure is used, i.e., a pressure equal to or less than 200 kPa. This low average pressure maintains most of the thickness of the air-laid preform 10. As further described herein, the hot pressing of the air-laid preform 10 can compress different portions of the air-laid preform 10 with different forces. Therefore, some portions of the 3D packaged product 20 may have a thickness substantially the same as or only slightly less than the thickness of the air-laid preform 10. In a particular embodiment, at least those portions of the 3D packaged product 20 that will come into contact with the goods to be protected preferably have the aforementioned thickness.

[0073] In one embodiment, the 3D-shaped packaged product 20 is configured to protect the packaged goods from electrostatic discharge (ESD). In such an embodiment, the air-laid preform 10 is conductive or semi-conductive. For example, the air-laid preform 10 may contain a conductive polymer or conductive fibers, such that the air-laid preform 10, and thus the 3D-shaped packaged product 20 manufactured by hot-pressing the air-laid preform 10, is conductive or semi-conductive. In this case, the air-laid preform 10 preferably contains a conductive polymer or fibers at a concentration not exceeding 10% by weight of the air-laid preform material 10, and more preferably not exceeding 5% by weight of the air-laid preform 10. In one embodiment, a portion of the natural fibers may be replaced with a conductive polymer or fibers. In another embodiment, the adhesive is made of or contains a conductive polymer. In a further embodiment, these two embodiments are combined. In a particular embodiment, the conductive polymer or fibers are carbon fibers. Instead of having conductive polymers or fibers, or as a supplement to having conductive polymers or fibers, the air-laid preform 10 may contain conductive or semi-conductive fillers, such as carbon black, which may be in the form of an additive, for example, an adhesive.

[0074] Therefore, in addition to natural fibers and thermoplastic polymer binders, the air-laid preform 10 may also contain one or more additives. These additives may be added to the thermoplastic polymer binder, and / or added during the production of the thermoplastic polymer binder. Alternatively or additionally, one or more additives may be added to the natural fibers. Alternatively or additionally, one or more additives may be added to the natural fibers and thermoplastic polymer binder, for example, during the air-laid process.

[0075] Illustrative but non-limiting examples of these additives include: conductive or semi-conductive fillers, coupling agents, flame retardants, dyes, impact modifiers, etc.

[0076] In some applications, it may be desirable to seal some or all of the surfaces of the 3D-shaped packaged product 20, for example, by heating, to prevent linting from the surfaces onto the packaged goods. The surfaces treated with heat during the hot-pressing process will be sealed, and no additional (heat) sealing is required. The at least one surface to be sealed may be sealed, for example, by heating, before or after the hot-pressing operation. Thus, in an embodiment, the 3D-shaped packaged product 20 includes at least one surface 21, 23 that is heat-sealed to prevent linting from the at least one surface 21, 23. Figure 1A 3D-shaped packaged product 20 is shown, having an upper surface 22, a bottom surface 24, and two end surfaces 21, 23. During hot pressing, a 3D-shaped cavity 26 is formed in the upper surface 22, thus giving the 3D shape of the packaged product 20. The end surfaces 21, 23 may then be fabricated without being processed by the air-laid preform 10, or they may be manufactured by sawing, cutting, or punching the air-laid preform 10. In this case, these surfaces 21, 23 may preferably be heat-sealed to prevent or at least suppress napping. The upper surface 22, or at least a portion thereof, has already been hot-pressed, and therefore typically does not require heat sealing. The heat sealing of the bottom surface 24 may be applied depending on whether the bottom surface of the air-laid preform 10 has been exposed to any heat during hot pressing.

[0077] In some applications, the 3D-shaped packaging product 20, or at least a portion thereof, may be laminated with a surface layer (e.g., a thermoplastic polymer film or nonwoven fabric). This prevents pilling and adds other functionalities to the surface, such as moisture barrier, tactile properties, color, and design. The film or nonwoven fabric can be made of any common thermoplastic polymer. Examples include the aforementioned thermoplastic polymer materials used as thermoplastic polymer adhesives. This layer may be heat-laminated or extruded onto the air-laid preform 10, and / or directly laminated onto the 3D-shaped packaging product 20. In embodiments, the film laminated to at least one surface or a portion thereof of the 3D-shaped packaging product 20 is conductive or semi-conductive to provide ESD protection for the packaged goods.

[0078] Therefore, in an embodiment, the 3D-shaped packaging product 20 includes at least one surface coated with a surface layer selected from a napping-inhibiting layer, a moisture-barrier layer, a tactile layer, and a coloring layer.

[0079] Films, fabrics, or surface layers can be attached to the air-laid preform 10 or the 3D packaged product 20 by means of a thin layer of hot melt adhesive, by an additional adhesive film, or by themselves becoming semi-molten and tacky during the hot lamination process. This operation can be performed before, after, or simultaneously with the hot pressing operation. If lamination is performed on at least one surface of the air-laid preform 10 (which will subsequently be processed by hot pressing), the softening point of the surface laminate should not exceed the degradation temperature of the natural fibers of the air-laid preform 10.

[0080] In a further embodiment, the surface layer can be applied by spraying it onto one or more surfaces of the 3D-shaped packaging product 20 or the air-laid preform 10. This layer can then contain any substance prepared as a solution, emulsion, or dispersion, such as thermoplastic polymers; natural polymers such as starch, agar, guar gum, or locust bean gum; microfibrils or nanofibrils of cellulose or lignocellulose; or mixtures thereof. Furthermore, the surface layer may also contain other substances, such as emulsifiers, stabilizers, conductive agents, etc., which provide additional functionality to the surface layer and the 3D-shaped packaging product 20.

[0081] Any hot pressing operation performed after the surface layer is provided should preferably be carried out at a temperature when the surface layer is in a semi-molten or malleable state but not in a molten state. If hot pressing is carried out at excessively high temperatures when the surface layer is in a molten stage, the surface layer may delaminate from the surface, and furthermore, if the temperature exceeds the degradation temperature of the natural fibers, the natural fibers may begin to degrade.

[0082] Another aspect of the invention relates to a method of manufacturing a 3D-shaped packaging product 20 for cushioning and / or insulating packaged goods, see [link to relevant documentation]. Figures 3 to 8 The method includes, in step S1, hot-pressing a punch 30 into an air-laid preform 10 under an average pressure equal to or less than 200 kPa to form a 3D-shaped packaging product 20 having a 3D shape at least partially defined by the punch 30. The air-laid preform 10 comprises at least 70% by weight of natural fibers and a thermoplastic polymer binder selected within a concentration range of 4% by weight to 30% by weight of the air-laid preform 10. The density of the 3D-shaped packaging product 20 is less than four times the density of the air-laid preform 10, and the density of the 3D-shaped packaging product 20 is 15 kg / m³. 3 Up to 240kg / m 3 Choose within the specified range.

[0083] The above discussion, especially regarding the density of the 3D packaged product 20 and the air-laid preform 10, and the thickness of the 3D packaged product 20 and the air-laid preform 10, also applies to the method of manufacturing the 3D packaged product 20.

[0084] Figure 7 Step S1, as shown, involves hot-pressing the punch 30 into the air-laid preform 10 at an average pressure equal to or less than 200 kPa. In a particular embodiment, the punch 30 is hot-pressed into the air-laid preform 10 at a pressure equal to or less than 175 kPa, more preferably equal to or less than 150 kPa. In this embodiment, the average pressure is defined as the force applied during hot pressing divided by the area of ​​the air-laid preform 10.

[0085] In the implementation, Figure 7 Step S1 includes hot-pressing a heated punch 30 into the air-laid preform 10. In this embodiment, the heated punch 30 is preferably heated to a temperature selected within the range of 120°C up to 210°C, and more preferably within the range of 120°C up to 190°C. Therefore, in this embodiment, heating of the air-laid preform 10 is achieved by using a heated punch 30. The punch 30 may then include a heating element 38, which is preferably a controllable heating element 38, to heat the punch 30 to the desired temperature for hot pressing. The temperature of the punch 30 generally depends on the type of natural fibers and thermoplastic polymer binder in the air-laid preform 10, as well as the hot pressing cycle time in step S1. However, the ranges presented above apply to most combinations of natural fibers, thermoplastic polymer binders, and cycle times.

[0086] In the embodiment, the air-laid blank 10 is located as follows: Figure 3 and Figure 4 On the base plate 40 shown. In an embodiment, Figure 7 Step S1 includes hot pressing a heated punch 30 onto an air-laid blank 10 located on a base plate 40 at a temperature equal to or lower than the ambient temperature.

[0087] In these embodiments, heating of the air-laid preform 10 is achieved via the punch 30, while the base plate 40 is at ambient temperature, typically room temperature, or may even be cooled. Keeping the base plate 40 at ambient temperature or even cooled reduces the risk of overheating the air-laid preform 10 during hot pressing in step S1, which could otherwise lead to the degradation of natural fibers, melting of the thermoplastic polymer binder, and damage to the porous structure of the air-laid preform 10 and the resulting 3D packaged product 20.

[0088] However, during the hot pressing process in step S1, the air-laid blank 10 can be positioned on the heated base plate 40, or even combined with the heated punch 30. In this case, the underside of the air-laid blank 10 facing the heated base plate 40 will also be heat-sealed during hot pressing.

[0089] In another embodiment, see Figure 5 Step S1 includes hot-pressing a heated punch 30 and a heated die 50 into an air-laid blank 10 located between the heated punch 30 and the heated die 50 to form a 3D-shaped packaged product 20 having a 3D shape at least partially defined by the punch 30 and the die 50. In this embodiment, the punch 30 forms a 3D-shaped cavity 26 in the formed 3D-shaped packaged product 20, while the die 50 includes a 3D-shaped cavity 52 defining the external geometry and 3D shape of the 3D-shaped packaged product 20.

[0090] In one embodiment, both the punch 30 and the die 50 are heated, preferably to a temperature selected within the range of 120°C to 210°C, and more preferably within the range of 120°C to 190°C. The punch 30 and the die 50 may be heated to the same temperature or different temperatures. In another embodiment, one of the punch 30 and the die 50 is heated while the other is at ambient temperature.

[0091] In the embodiments presented above, at least one of the molds 30 and 50 used in step S1 of the hot pressing process is heated. In another embodiment, the method includes, as described above... Figure 8 The additional step S10 is shown. Step S10 includes hot pressing the punch 30 into the air-laid blank 10 (in Figure 7 Before step S1 shown, at least a portion of the airflow-layout blank 10 is heated.

[0092] Therefore, the air-laid preform 10 is heated (preferably before the hot pressing operation), rather than the punch 30 and / or any die 50. The air-laid preform 10 is then preferably heated to a temperature at which the thermoplastic polymer adhesive or at least a portion thereof is in a stretchable but unmelted state. For most thermoplastic polymer adhesives, this temperature is in the range of 80°C to 180°C, for example, in the range of 100°C to 180°C or 120°C to 160°C. Therefore, in this embodiment, it is preferable to heat the air-laid preform 10 to a temperature in the range of 80°C to 180°C.

[0093] In this embodiment, the punch 30 and the base plate 40 or the die 50 may be independently exposed to ambient temperature (e.g., room temperature) or cooled.

[0094] Alternatively, Figure 8 The embodiment shown, namely the heating of the air-laid blank 10, can be combined with the use of a heated punch 30 or a heated punch 30 and / or a heated die 50.

[0095] In embodiments particularly suitable for producing deep cavities or steep walls, step S1 includes hot-pressing a punch 30, including at least one cavity-defining structure 32 with a cutting edge 34, into an air-laid blank 10. See [link to previous section] Figure 6In this embodiment, at least one cavity defining or protruding edge of the punch 30 includes a cutting edge 34. This means that when the punch 30 is pressed into the air-laid preform 10 in step S1, the at least one cutting edge 34 cuts into the air-laid preform 10. Thus, simultaneous cutting and pressing operations are achieved. The at least one cutting edge 34 of the at least one cavity defining structure 32 helps to form a well-defined 3D cavity 26 in the formed 3D packaged product 20, and wherein the cavity 26 is shaped into a desired shape, for example, so that the packaged goods can be fitted into the cavity 26.

[0096] The hot pressing in step S1 results in the 3D packaged product 20 having a considerable degree of porosity to suit cushioning and / or insulation. Therefore, the punch 30 cannot be pressed too forcefully into the air-laid preform 10, otherwise this would result in the 3D packaged product 20 being too compact and dense. If the punch 30 not only presses into the air-laid preform 10 but also performs a cutting action during hot pressing, the shape of the cavity 26 in the 3D packaged product 20 can be more precisely defined.

[0097] The cutting edge 34 can be achieved by making a cavity defining structure 32 act like the sharp edge of a knife or blade, while the main surface 36 of at least one cavity defining structure 32 is pressed into the air-laid blank 10.

[0098] In the embodiment, each edge 34 of all cavity defining structures 32 of the punch 30 is a cutting edge 34 or at least a portion thereof.

[0099] In one embodiment, the overall 3D shape of the 3D package 20 is defined at least partially by a punch 30 and optionally a die 50, the punch 30 forming at least one cavity 26 within the 3D package 20, and the die 50 defining at least partially the external shape of the 3D package 20. The 3D shape and geometry of the 3D package 20 are selected at least in part based on the shape of the packaged goods to be protected by the 3D package 20 or according to the intended use of the 3D package 20 (e.g., in the form of a food container).

[0100] The method may also include the additional step of cutting the air-laid preform 10 and / or the 3D packaged product 20 into the desired shape, for example by sawing, cutting, or stamping die. This cutting operation may be performed before, during, and / or after hot pressing.

[0101] In the implementation, Figure 7Step S1 shown is performed without water. Therefore, no water is added during the hot pressing operation. The air-laid preform 10 is preferably at an ambient equilibrium moisture content.

[0102] The above-described and Figure 7 and Figure 8 The method shown is suitable for forming a 3D-shaped packaged product 20 according to the present invention.

[0103] The above embodiments should be understood as several illustrative examples of the present invention. Those skilled in the art will understand that various modifications, combinations, and changes can be made to the embodiments without departing from the scope of the invention. In particular, where technically possible, different parts of different embodiments can be combined in other configurations.

Claims

1. A three-dimensional (3D) packaging product (20) for cushioning and / or insulating packaged goods, wherein, The three-dimensional (3D) packaged product (20) is formed by hot-pressing an air-laid preform (10) at an average pressure equal to or below 200 kPa. The air-laid preform (10) comprises at least 70% by weight of natural fibers and a thermoplastic polymer binder selected from the air-laid preform (10) at a concentration ranging from 4% to 30% by weight. The density of the three-dimensional (3D) packaged product (20) is less than four times the density of the air-laid preform (10), and the density of the three-dimensional (3D) packaged product (20) is 15 kg / m³. 3 Up to 240 kg / m 3 Choose within the specified range.

2. The three-dimensional (3D) packaged product (20) according to claim 1, wherein, The natural fiber is wood fiber.

3. The three-dimensional (3D) packaged product (20) according to claim 2, wherein, The natural fiber is cellulose and / or lignocellulose fiber.

4. The three-dimensional (3D) packaged product (20) according to claim 2, wherein, The natural fibers are cellulose and / or lignocellulose pulp fibers produced by chemical, mechanical and / or chemomechanical pulping of softwood and / or hardwood.

5. The three-dimensional (3D) packaged product (20) according to claim 2, wherein, The natural fiber is cellulose and / or lignocellulose pulp fiber, in the form of sulfate pulp, sulfite pulp, thermomechanical pulp (TMP), high-temperature thermomechanical pulp (HTMP), mechanical fiber for medium density fiberboard (MDF-fiber), chemithermomechanical pulp (CTMP), high-temperature chemithermomechanical pulp (HTCTMP), and combinations thereof.

6. The three-dimensional (3D) packaged product (20) according to any one of claims 1 to 5, wherein, The density of the three-dimensional (3D) packaged product (20) is equal to or less than three times the density of the air-laid preform (10).

7. The three-dimensional (3D) packaged product (20) according to claim 6, wherein, The density of the three-dimensional (3D) packaged product (20) is equal to or less than twice the density of the air-laid blank (10).

8. The three-dimensional (3D) packaged product (20) according to any one of claims 1 to 5, wherein, The density of the three-dimensional (3D) packaged product (20) is 15 kg / m³. 3 Up to 200 kg / m 3 Choose within the specified range.

9. The three-dimensional (3D) packaged product (20) according to claim 8, wherein, The density of the three-dimensional (3D) packaged product (20) is 15 kg / m³. 3 Up to 150 kg / m 3 Choose within the specified range.

10. The three-dimensional (3D) packaged product (20) according to claim 9, wherein, The density of the three-dimensional (3D) packaged product (20) is 15 kg / m³. 3 Up to 100 kg / m 3 Choose within the specified range.

11. The three-dimensional (3D) packaged product (20) according to claim 8, wherein, The density of the three-dimensional (3D) packaged product (20) is 20 kg / m³. 3 Up to 75 kg / m 3 Choose within the specified range.

12. The three-dimensional (3D) packaged product (20) according to claim 11, wherein, The density of the three-dimensional (3D) packaged product (20) is 25 kg / m³. 3 Up to 70 kg / m 3 Choose within the specified range.

13. The three-dimensional (3D) packaged product (20) according to claim 12, wherein, The density of the three-dimensional (3D) packaged product (20) is 25 kg / m³. 3 Up to 65 kg / m 3 Choose within the specified range.

14. The three-dimensional (3D) packaged product (20) according to any one of claims 1 to 5, wherein, The density of the air-laid preform (10) is 10 kg / m³. 3 Up to 60 kg / m 3 Choose within the specified range.

15. The three-dimensional (3D) packaged product (20) according to any one of claims 1 to 5, wherein, The air-laid preform (10) contains a thermoplastic polymer binder, the concentration of which is selected in the range of 15% by weight to 30% by weight of the air-laid preform (10).

16. The three-dimensional (3D) packaged product (20) according to claim 15, wherein, The air-laid preform (10) contains a thermoplastic polymer binder, the concentration of which is selected in the range of 17.5% by weight to 30% by weight of the air-laid preform (10).

17. The three-dimensional (3D) packaged product (20) according to claim 16, wherein, The air-laid preform (10) contains a thermoplastic polymer binder, the concentration of which is selected in the range of 17.5% by weight to 25% by weight of the air-laid preform (10).

18. The three-dimensional (3D) packaged product (20) according to any one of claims 1 to 5, wherein, The softening point of the thermoplastic polymer adhesive or at least a portion thereof does not exceed the degradation temperature of the natural fiber.

19. The three-dimensional (3D) packaged product (20) according to any one of claims 1 to 5, wherein, The thermoplastic polymer adhesive is or comprises a one-component thermoplastic polymer fiber made from: i) a material selected from polyethylene (PE), ethylene-acrylic acid copolymer (EAA), ethylene-vinyl acetate (EVA), polypropylene (PP), polystyrene (PS), polybutylene terephthalate (PBAT), polybutylene succinate (PBS), polylactic acid (PLA), polyethylene terephthalate (PET), polycaprolactone (PCL), copolymers thereof, and mixtures thereof, and ii) optionally one or more additives.

20. The three-dimensional (3D) packaged product (20) according to any one of claims 1 to 5, wherein, The thermoplastic polymer adhesive is or comprises a two-component thermoplastic polymer fiber having a core component and / or sheath component made of: i) one or more materials selected from polyethylene (PE), ethylene-acrylic acid copolymer (EAA), ethylene-vinyl acetate (EVA), polypropylene (PP), polystyrene (PS), polybutylene terephthalate (PBAT), polybutylene succinate (PBS), polylactic acid (PLA), polyethylene terephthalate (PET), polycaprolactone (PCL), copolymers thereof, and mixtures thereof, and ii) optionally one or more additives.

21. The three-dimensional (3D) packaged product (20) according to any one of claims 1 to 5, wherein, At least a portion of the thermoplastic polymer adhesive is water-soluble at the re-sizing temperature selected for re-sizing the three-dimensional (3D) packaged product (20).

22. The three-dimensional (3D) packaged product (20) according to any one of claims 1 to 5, wherein, The thermoplastic polymer adhesive is or comprises a single-component thermoplastic polymer fiber made of: i) a material selected from polyvinyl alcohol (PVA), polyethylene glycol (PEG), poly(2-ethyl-2-oxazoline) (PEOX), polyvinyl ether (PVE), polyvinylpyrrolidone (PVP), polyacrylic acid (PAA), polymethacrylic acid (PMAA), copolymers thereof, and mixtures thereof, and ii) optionally one or more additives.

23. The three-dimensional (3D) packaged product (20) according to any one of claims 1 to 5, wherein, The thermoplastic polymer adhesive is or comprises a two-component thermoplastic polymer fiber having a core component and / or sheath component made of: i) one or more materials selected from polyvinyl alcohol (PVA), polyethylene glycol (PEG), poly(2-ethyl-2-oxazoline) (PEOX), polyvinyl ether (PVE), polyvinylpyrrolidone (PVP), polyacrylic acid (PAA), polymethacrylic acid (PMAA), copolymers thereof, and mixtures thereof, and ii) optionally one or more additives.

24. The three-dimensional (3D) packaged product (20) according to any one of claims 1 to 5, wherein, The thermoplastic polymer adhesive is or comprises a two-component thermoplastic polymer fiber including the following: The core component is made from: i) a material selected from polyethylene (PE), ethylene-acrylic acid copolymer (EAA), ethylene-vinyl acetate (EVA), polypropylene (PP), polystyrene (PS), polybutylene terephthalate (PBAT), polybutylene succinate (PBS), polylactic acid (PLA), polyethylene terephthalate (PET), polycaprolactone (PCL), copolymers thereof, and mixtures thereof; and ii) optionally one or more additives; and The sheath component is made from: i) materials selected from polyvinyl alcohol (PVA), polyethylene glycol (PEG), poly(2-ethyl-2-oxazoline) (PEOX), polyvinyl ether (PVE), polyvinylpyrrolidone (PVP), polyacrylic acid (PAA), polymethacrylic acid (PMAA), copolymers thereof, and mixtures thereof, and ii) optionally one or more additives.

25. The three-dimensional (3D) packaged product (20) according to any one of claims 1 to 5, wherein, The thermoplastic polymer adhesive is or comprises thermoplastic polymer fibers whose length-weighted average fiber length is selected within a range of 100% to 600% of the length-weighted average fiber length of the natural fibers.

26. The three-dimensional (3D) packaged product (20) according to claim 25, wherein, The length-weighted average fiber length of the thermoplastic polymer fiber is selected within a range of 150% to 450% of the length-weighted average fiber length of the natural fiber.

27. The three-dimensional (3D) packaged product (20) according to claim 26, wherein, The length-weighted average fiber length of the thermoplastic polymer fiber is selected within a range of 200% to 400% of the length-weighted average fiber length of the natural fiber.

28. The three-dimensional (3D) packaged product (20) according to claim 27, wherein, The length-weighted average fiber length of the thermoplastic polymer fiber is selected within a range of 250% to 350% of the length-weighted average fiber length of the natural fiber.

29. The three-dimensional (3D) packaged product (20) according to any one of claims 1 to 5, wherein, The thermoplastic polymer adhesive is or comprises thermoplastic polymer fibers whose length-weighted average fiber length is selected in the range of 1 mm to 12 mm.

30. The three-dimensional (3D) packaged product (20) according to claim 29, wherein, The length-weighted average fiber length of the thermoplastic polymer fiber is selected within a range of 1 mm to 10 mm.

31. The three-dimensional (3D) packaged product (20) according to claim 30, wherein, The length-weighted average fiber length of the thermoplastic polymer fiber is selected within the range of 2 mm to 8 mm.

32. The three-dimensional (3D) packaged product (20) according to claim 31, wherein, The length-weighted average fiber length of the thermoplastic polymer fiber is selected within a range of 2 mm to 6 mm.

33. The three-dimensional (3D) packaged product (20) according to any one of claims 1 to 5, wherein, The thickness of the air-laid blank (10) is at least 20 mm.

34. The three-dimensional (3D) packaged product (20) according to claim 33, wherein, The thickness of the air-laid blank (10) is at least 30 mm.

35. The three-dimensional (3D) packaged product (20) according to claim 34, wherein, The thickness of the air-laid blank (10) is at least 40 mm.

36. The three-dimensional (3D) packaged product (20) according to any one of claims 1 to 5, wherein, The three-dimensional (3D) packaged product (20) includes at least one surface (21, 23) that is heat-sealed to suppress napping from the at least one surface (21, 23).

37. The three-dimensional (3D) packaged product (20) according to any one of claims 1 to 5, wherein, The three-dimensional (3D) packaged product (20) includes at least one surface coated with a surface layer selected from a napping-inhibiting layer, a moisture-barrier layer, a tactile layer, and a coloring layer.

38. The three-dimensional (3D) packaged product (20) according to claim 37, wherein, The surface layer is adhered to at least one surface of the three-dimensional (3D) packaged product (20) by hot melt adhesive and / or by adhesive film.

39. A method for manufacturing a three-dimensional (3D) shaped packaging product (20) for cushioning and / or insulation of packaged goods, said method comprising: Under an average pressure equal to or less than 200 kPa, a punch (30) is hot-pressed (S1) into an air-laid preform (10) to form a three-dimensional (3D) packaged product (20) having a 3D shape at least partially defined by the punch (30), the air-laid preform (10) comprising at least 70% by weight of natural fibers and a thermoplastic polymer binder selected from 4% by weight to 30% by weight of the air-laid preform (10), wherein the density of the three-dimensional (3D) packaged product (20) is less than four times the density of the air-laid preform (10), and the density of the three-dimensional (3D) packaged product (20) is 15 kg / m³. 3 Up to 240 kg / m 3 Choose within the specified range.

40. The method according to claim 39, wherein, The hot pressing (S1) of the punch (30) includes hot pressing (S1) the heated punch (30) into the air-laid blank (10).

41. The method according to claim 40, wherein, The heated punch (30) is heated to a temperature selected in the range of 120°C to 210°C.

42. The method of claim 40, wherein, The hot pressing (S1) of the heated punch (30) includes pressing (S1) the heated punch (30) into an air-laid blank (10) located on a base plate (40) at a temperature equal to or lower than the ambient temperature.

43. The method according to claim 39, wherein, The hot pressing (S1) of the punch (30) includes hot pressing (S1) the punch (30) and the die (50) into an airflow-laid blank (10) located between the punch (30) and the die (50) to form a three-dimensional (3D) packaged product (20) having a 3D shape at least partially defined by the punch (30) and the die (50), wherein at least one of the punch (30) and the die (50) is heated.

44. The method according to claim 43, wherein, At least one of the punch (30) and the die (50) is heated to a temperature selected in the range of 120°C to a maximum of 210°C.

45. The method according to any one of claims 39 to 44, further comprising heating (S10) at least a portion of the air-laid blank (10) before hot pressing (S1) the punch (30) into the air-laid blank (10).

46. ​​The method of claim 45, wherein the air-laid blank (10) is heated to a temperature selected in the range of 80°C up to 180°C.

47. The method according to any one of claims 39 to 44, wherein, The hot pressing (S1) of the punch (30) includes hot pressing (S1) of the punch (30) including at least one cavity defining structure (32) having a cutting edge (34) into the air-laid blank (10).

48. The method according to any one of claims 39 to 44, wherein, The hot pressing (S1) of the punch (30) includes pressing the punch (30) into the air-laid blank (10) at an average pressure equal to or less than 175 kPa.

49. The method according to claim 48, wherein, The hot pressing (S1) of the punch (30) includes pressing the punch (30) into the air-laid blank (10) at an average pressure equal to or less than 150 kPa.

50. The method according to any one of claims 39 to 44, wherein, The hot pressing (S1) of the punch (30) includes hot pressing (S1) the punch (30) into the air-laid blank (10) to form a three-dimensional (3D) packaged product (20) as claimed in any one of claims 1 to 38.

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