Fibers and filaments for three-dimensional printing

Abstract

The present invention relates to a fiber made from a mixture comprising an aliphatic polyester, an aliphatic-aromatic polyester and a polyhydroxyalkanoate, and to a method for producing such a fiber. The invention also relates to a filament suitable for three-dimensional printing, said filament being made from a mixture comprising an aliphatic polyester, an aliphatic-aromatic polyester and a polyhydroxyalkanoate, and to a method for producing such a filament.

Description

[0001] Cross-references to related applications

[0002] This application claims the benefit of priority to European Patent Application 23162116.0, filed on March 15, 2023, the contents of which are incorporated herein by reference in their entirety for all purposes. Technical Field

[0003] This invention relates to a fiber comprising aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, a method for preparing such a fiber, and the use of such a fiber in yarn or textiles. The invention also relates to a filament suitable for 3D printing, comprising aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, a method for preparing such a filament, and the use of such a filament for 3D printing. Background Technology

[0004] Sustainable textiles should be based on ecological, economic, and social sustainability. Sustainable products should take into account factors from raw materials to processing, finishing, sales, and recycling.

[0005] Fibers currently used in sustainable textiles include, for example, natural fibers such as cotton, wool, linen, and SeaCell. TM (Cellulose fibers obtained from algae, produced by SmartFiber AG), recycled fibers, such as recycled polyester (e.g., from polyethylene terephthalate (PET) bottles), Econyl ® (Regenerated nylon fiber) or regenerated fiber (a general term for fibers produced from natural materials such as wood through chemical methods), such as Lyocell (e.g., under the trade name Tencel). TM (Originally from Lenzing) or Modal.

[0006] However, despite their use in sustainable textiles, these fibers still have various drawbacks. For example, the production of cotton and wool requires high water consumption and is associated with high land consumption. Obtaining recycled fibers, such as recycled PET, typically requires significant amounts of energy, water, and chemicals.

[0007] Further, it is desired that sustainable textiles and fibers be suitable for use under the concept of a circular economy. In particular, it is hoped that textiles and fibers can be used in biological cycles by exhibiting suitable biodegradability and thus avoiding non-degradable waste, for example, under cradle-to-cradle design. The beneficial entry of fibers or textiles into the biological cycle is achieved when textile products are recycled and fed into industrial composting after the end of their life cycle. This produces biomass and biogas (CH4, CO2, water), which can be directly fed into the biological cycle.

[0008] Therefore, there is a continuous demand for fibers, especially fibers that meet ecological requirements. Therefore, the object of this invention is to provide such fibers.

[0009] Similar considerations apply to filaments suitable for 3D printing and 3D printed articles. Therefore, there is a need for filaments suitable for 3D printing, especially filaments that meet ecological requirements. Similarly, there is a need for 3D printed articles that particularly meet ecological requirements. Therefore, another object of the present invention is to provide such filaments suitable for 3D printing. Furthermore, an object of the present invention is to provide such 3D printed articles. Summary of the Invention

[0010] This objective is achieved by fibers, yarns, garments, and methods having the features of the independent claims.

[0011] In a first aspect, the present invention relates to a fiber made from a mixture comprising aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate.

[0012] Secondly, the present invention relates to a yarn comprising the fibers of the present invention.

[0013] Thirdly, the present invention relates to a textile comprising the fiber or yarn of the present invention.

[0014] Fourthly, the present invention relates to a method for preparing fibers according to the present invention, comprising:

[0015] - A melt containing aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate is spun through a spinning nozzle to obtain precursor fibers; and

[0016] - Cool the precursor fiber to obtain the fiber.

[0017] Fifthly, the present invention relates to the use of melts comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates for the preparation of fibers, wherein the fibers are as defined herein.

[0018] In a sixth aspect, the present invention relates to the use of melts comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates for the preparation of fibers.

[0019] In a seventh aspect, the present invention relates to the use of mixtures comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates for the preparation of fibers, wherein the fibers are as defined herein.

[0020] Eighthly, the present invention relates to the use of mixtures comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates in the preparation of fibers.

[0021] The object of the present invention is also achieved by a filament suitable for three-dimensional printing, a roller comprising the filament, a barrel suitable for a three-dimensional printer, a three-dimensional printed article, and a method having the features of the independent claims.

[0022] Ninthly, the present invention relates to a filament suitable for three-dimensional printing, said filament being made of a mixture comprising aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate.

[0023] Tenthly, the present invention relates to a roller comprising a filament suitable for three-dimensional printing according to the present invention. Eleventhly, the present invention relates to a barrel suitable for a three-dimensional printer, the barrel comprising a filament suitable for three-dimensional printing according to the present invention.

[0024] In a twelfth aspect, the present invention relates to a three-dimensional printed article which can be obtained by subjecting the filament of the present invention suitable for three-dimensional printing to three-dimensional printing or obtained therefrom.

[0025] In a thirteenth aspect, the present invention relates to a method for preparing filaments suitable for three-dimensional printing according to the invention, the method comprising extruding a melt comprising an aliphatic polyester, an aliphatic-aromatic polyester and a polyhydroxyalkanoate into filament form.

[0026] In a fourteenth aspect, the present invention relates to the use of melts comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates for preparing filaments suitable for three-dimensional printing, wherein the filaments are as defined herein.

[0027] In a fifteenth aspect, the present invention relates to the use of melts comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates for preparing filaments suitable for three-dimensional printing.

[0028] In a fourteenth aspect, the present invention relates to the use of mixtures comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates for preparing filaments suitable for three-dimensional printing, wherein the filaments are as defined herein.

[0029] In a fifteenth aspect, the present invention relates to the use of mixtures comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates for the preparation of filaments suitable for three-dimensional printing.

[0030] Brief description of the attached figures

[0031] The invention will be better understood by referring to the detailed description taken in conjunction with non-limiting embodiments and the accompanying drawings, in which: Figure 1 A schematic diagram of a melt spinning apparatus for preparing fibers according to an embodiment of the present invention is shown.

[0032] Figure 2A schematic diagram showing the fiber production process according to an embodiment of the present invention is provided, the production process including further processing of the fiber on a fiber post-processing line.

[0033] Figure 3 The images show granules that can be used to prepare mixtures of fibers or filaments suitable for injection molding according to the invention, fibers according to embodiments of the invention, yarns made from said fibers, and shirts made using fibers according to embodiments of the invention (particularly yarns made from said fibers). Figure 3 Also shown is a filament suitable for 3D printing according to an embodiment of the invention.

[0034] Figure 4 The photograph shows other views of the shirt, which is made using fibers according to embodiments of the invention, particularly yarns made from said fibers. Detailed Implementation

[0035] fiber

[0036] As described above, in a first aspect, the present invention relates to fibers made from a mixture comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates.

[0037] It has been found that mixtures comprising aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates are highly suitable for fiber preparation. In particular, fibers comprising aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates can be obtained by melt spinning a mixture comprising these compounds. In this respect, mixtures comprising aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates have been found to exhibit good spinnability, which is useful for melt spinning. Fibers comprising aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates have also been shown to exhibit good properties for use as textile fibers, such as good mechanical strength, elongation, flexibility, elasticity, and abrasion resistance. As a further advantage, the fiber preparation requires significantly less water and land consumption than cotton (see Example 3). As yet another advantage, fiber production can be carried out without toxic substances such as antimony (see Example 2). Furthermore, by using aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates, biodegradable fibers can be obtained, even meeting the harmonized European standard EN 13432, and therefore can be processed in industrial composting plants. The fibers of this invention can be used as textile fibers, for example, for producing clothing such as shirts (see Example 4 and...). Figure 3 and 4It has been found that this garment is so biodegradable that a single garment completely degrades / decomposes within just a few weeks of being placed in organic waste. It should be noted that various products, such as sheets, foils, and fibers, contain one or more of aliphatic polyesters, aliphatic-aromatic polyesters, and / or polyhydroxyalkanoates, as described, for example, in EP3626767, WO 2010 / 034689, WO 2010 / 034711, WO 2015 / 169660, EP1966419, EP2984138, CN 103668540, CN103668541, WO 2014 / 173055, and CN 104120502.

[0038] As used herein, the term "aliphatic polyester" generally refers to polyesters typically synthesized via the polycondensation reaction of aliphatic diols with aliphatic dicarboxylic acids or their anhydrides. As an illustrative example, the aliphatic polyester used herein may contain aliphatic C2-C... 20 Dicarboxylic acids and aliphatic C2-C 12 Diols. Preferably, the aliphatic diol is an aliphatic C2-C8 diol. More preferably, the aliphatic diol is an aliphatic C2-C6 diol. Even more preferably, the aliphatic diol is an aliphatic C3 or aliphatic C4 diol. As an illustrative example, aliphatic diols used in aliphatic polyesters may include ethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, and 1,6-hexanediol. Preferably, the aliphatic diol is 1,3-propanediol or 1,4-butanediol. More preferably, the aliphatic diol is 1,4-butanediol. Preferably, the aliphatic dicarboxylic acid is an aliphatic C2-C6 diol. 12 Dicarboxylic acid. More preferably, the aliphatic dicarboxylic acid is an aliphatic C2-C8 dicarboxylic acid, and even more preferably an aliphatic C4 dicarboxylic acid. As an illustrative example, the aliphatic dicarboxylic acid used in the aliphatic polyester may include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, etc. Preferably, the aliphatic dicarboxylic acid is malonic acid or succinic acid. More preferably, the aliphatic dicarboxylic acid is succinic acid. Optionally, when the dicarboxylic acid is an aliphatic C2-C8 dicarboxylic acid... 12 When dicarboxylic acid is used, the aliphatic polyester may further contain components different from C2-C. 12 Other aliphatic C6-C dicarboxylic acids 20 Dicarboxylic acids. As an illustrative example, optional aliphatic C6-C... 12 Dicarboxylic acids may include adipic acid, octanoic acid, azelaic acid, sebacic acid, brassic acid, and arachidonic acid. Preferably, optionally, aliphatic C6-C... 12 Dicarboxylic acids can include adipic acid, octanoic acid, azelaic acid, sebacic acid, and brassic acid. Optional aliphatic C2-C... 12Dicarboxylic acids may be present in the aliphatic polyester at a ratio of 0-10 mol% based on 100 mol% of the total aliphatic dicarboxylic acid in the aliphatic polyester. Optionally, the aliphatic polyester may further comprise chain extenders and / or branching agents. Optional chain extenders and / or branching agents may include, as illustrative examples, polyfunctional isocyanates, isocyanurates, oxazolines, carboxylic anhydrides such as maleic anhydride, epoxides (particularly epoxy-containing poly(meth)acrylates), at least triols, and at least tricarboxylic acids. Optional chain extenders and / or branching agents may be present in the aliphatic polyester at a ratio of 0 to 1 mol% based on 100 wt% of the total aliphatic dicarboxylic acid and aliphatic diol. The term "aliphatic polyester" may also include mixtures of two or more different aliphatic polyesters. The number-average molecular weight (Mn) of the aliphatic polyester can be from 2,500 to 150,000 g / mol, preferably from 5,000 to 100,000 g / mol, more preferably from 7,500 to 75,000 g / mol, even more preferably from 10,000 to 65,000 g / mol, and even more preferably from 12,000 to 60,000 g / mol. The weight-average molecular weight (Mw) of the aliphatic polyester can be from 5,000 to 300,000 g / mol, preferably from 10,000 to 250,000 g / mol, more preferably from 20,000 to 220,000 g / mol, even more preferably from 50,000 to 200,000 g / mol, and even more preferably from 60,000 to 190,000 g / mol. The polydispersity index (i.e., the ratio of weight-average molecular weight to number-average molecular weight (Mw / Mn)) of the aliphatic polyester can be 1 to 6, preferably 1 to 4, more preferably 1.0 to 3.0, even more preferably 1.2 to 2.0, and even more preferably 1.4 to 1.8.

[0039] Illustrative examples of aliphatic polyesters that can be used in this invention may include aliphatic polyesters selected from the following: polybutylene succinate (PBS), polyethylene oxalate, polyethylene malonate, polyethylene succinate, polypropylene oxalate, polypropylene malonate, polypropylene oxalate, polybutylene malonate, polybutylene oxalate, polybutylene malonate, polybutylene co-adipate (PBSA), polybutylene co-azelate (PBSAz), polybutylene co-brassilicate (PBSBr), and any combination thereof. The aliphatic polyester may preferably be selected from: polybutylene succinate (PBS), polybutylene co-adipate (PBSA), polybutylene co-azelate (PBSAz), polybutylene co-brassilicate (PBSBr), and any combination thereof. In a preferred embodiment, the aliphatic polyester is polybutylene succinate. The term "polybutylene succinate" as used herein specifically refers to the condensation product of aliphatic dicarboxylic acid succinic acid and aliphatic diol 1,4-butanediol. The aliphatic polyesters polybutylene succinate (PBS) and polybutylene co-succinate (PBSA) are commercially available, for example, from Showa Highpolymer under the brand name Blanche. ® Obtained, and from Mitsubishi via GSPIa ® The aliphatic polyester, particularly polybutylene succinate (PBS), can be obtained from renewable or fossil resources. Preferably, an aliphatic polyester from a renewable resource is used. More preferably, bio-based polybutylene succinate (PBS) produced from bio-based succinic acid and 1,4-butanediol can be used, for example, under the trade name BioPBS. TMFZ71 is commercially available from Mitsubishi Chemicals. Preferably, the aliphatic polyester is biodegradable. In particular, polybutylene succinate (PBS) is a biodegradable aliphatic polyester. Preferably, the fiber contains 30 to 70% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, based on a total of 100% by weight. More preferably, the fiber contains 35 to 65% by weight of aliphatic polyester, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. Even more preferably, the fiber contains 40 to 60% by weight or 42 to 62% by weight of aliphatic polyester, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. Even more preferably, the fiber contains 45 to 55% by weight of aliphatic polyester, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. Specifically, these ranges can be applied when the aliphatic polyester is polybutylene succinate. In a preferred embodiment, the fiber contains 52% polybutylene succinate, based on a total amount of 100% by weight of polybutylene succinate, aliphatic aromatic polyester, and polyhydroxyalkanoate.

[0040] As used herein, the term "aliphatic-aromatic polyester" generally refers to a polyester typically synthesized from aliphatic diols, aliphatic dicarboxylic acids, and aromatic dicarboxylic acids. As an illustrative example, the aliphatic-aromatic polyester may contain aliphatic C2-C... 20 Dicarboxylic acids, aromatic dicarboxylic acids, and aliphatic C2-C 12 Diols. Preferably, the aliphatic diol is an aliphatic C2-C8 diol. More preferably, the aliphatic diol is an aliphatic C2-C6 diol. Even more preferably, the aliphatic diol is an aliphatic C3 or aliphatic C4 diol. As an illustrative example, aliphatic diols used in aliphatic-aromatic polyesters may include ethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, and 1,6-hexanediol. Preferably, the aliphatic diol is 1,3-propanediol or 1,4-butanediol. More preferably, the aliphatic diol is 1,4-butanediol. Preferably, the aliphatic dicarboxylic acid is an aliphatic C2-C6 diol. 12 Dicarboxylic acids. More preferably, the aliphatic dicarboxylic acid is an aliphatic C4-C... 10Dicarboxylic acids, and even more preferably aliphatic C6 dicarboxylic acids. As an illustrative example, the aliphatic dicarboxylic acid used in aliphatic-aromatic polyesters may include glutaric acid, adipic acid, pimelic acid, azelaic acid, sebacic acid, brassic acid, octanoic acid, and itaconic acid. Preferably, the aliphatic dicarboxylic acid is adipic acid, azelaic acid, or sebacic acid. More preferably, the aliphatic dicarboxylic acid is adipic acid. Preferably, the aromatic dicarboxylic acid is terephthalic acid. The aromatic dicarboxylic acid, particularly terephthalic acid, may be present in the aliphatic-aromatic polyester in an amount, for example, 30-70 mol%, preferably 40-60 mol%, more preferably 40-55 mol%, based on a total aliphatic and aromatic dicarboxylic acids of 100 mol%. Optionally, the aliphatic polyester may further comprise chain extenders and / or branching agents. Optional chain extenders may include, as an illustrative example, di- or polyfunctional isocyanates, preferably hexamethylene diisocyanate. Optional branching agents may include, as illustrative examples, trimethylolpropane, pentaerythritol, and preferably glycerol. Optional chain extenders and / or branching agents may be present in the aliphatic polyester in a proportion of 0 to 1% by weight, based on a total of 100% by weight of aliphatic dicarboxylic acids, aromatic dicarboxylic acids, and aliphatic diols. The term "aliphatic-aromatic polyester" may also include mixtures of two or more different aliphatic-aromatic polyesters. The number-average molecular weight (Mn) of the aliphatic-aromatic polyester may be from 1,000 to 500,000 g / mol, preferably from 5,000 to 300,000 g / mol, more preferably from 5,000 to 100,000 g / mol, even more preferably from 10,000 to 75,000 g / mol, and even more preferably from 15,000 to 50,000 g / mol. The weight-average molecular weight (Mw) of the aliphatic-aromatic polyester can be from 10,000 to 500,000 g / mol, preferably from 20,000 to 400,000 g / mol, more preferably from 30,000 to 300,000 g / mol, and even more preferably from 60,000 to 200,000 g / mol. The polydispersity index (i.e., the ratio of weight-average molecular weight to number-average molecular weight (Mw / Mn)) of the aliphatic-aromatic polyester can be from 1 to 6, preferably from 2 to 4, more preferably from 1.0 to 3.0, even more preferably from 1.2 to 2.0, and even more preferably from 1.4 to 1.8.

[0041] The aliphatic-aromatic polyesters that can be used in this invention may include, but are not limited to, polybutylene terephthalate (PBAT), polybutylene terephthalate succinate (PBST), polybutylene terephthalate sebacic acid (PBSeT), and any combination thereof. In a preferred embodiment, the aliphatic-aromatic polyester is polybutylene terephthalate (PBAT). The term "polybutylene terephthalate" as used herein refers to an aliphatic-aromatic polyester comprising aliphatic dicarboxylic acid adipic acid, aromatic dicarboxylic acid terephthalic acid, and aliphatic diol 1,4-butanediol. The aliphatic-aromatic polyester, particularly polybutylene terephthalate (PBAT), can be obtained from renewable or fossil resources. Preferably, aliphatic-aromatic polyesters from renewable resources are used. Polybutylene terephthalate (PBAT) is, for example, produced by BASF using Ecoflex. ® Sales, such as Ecoflex ® F Blend C1200 or Ecoflex ® FBX 7011, or by ShowaDenko with Bionolle ® For sale. Preferably, the aliphatic-aromatic polyester is biodegradable. In particular, polybutylene terephthalate (PBAT) is a biodegradable aliphatic-aromatic polyester.

[0042] Preferably, the fiber comprises 10 to 60% by weight of aliphatic-aromatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, based on a total of 100% by weight. More preferably, the fiber comprises 20 to 50% by weight of aliphatic-aromatic polyester, based on a total of 100% by weight of aliphatic-aromatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. Even more preferably, the fiber comprises 25 to 40% by weight or 26 to 46% by weight of aliphatic-aromatic polyester, based on a total of 100% by weight of aliphatic-aromatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. Even more preferably, the fiber comprises 30 to 40% by weight of aliphatic-aromatic polyester, based on a total of 100% by weight of aliphatic-aromatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. In particular, these ranges can be applied when the aliphatic-aromatic polyester is polybutylene terephthalate (PBAT). In a preferred embodiment, the fiber comprises 36% by weight of polybutylene adipate terephthalate (PBAT), based on a total amount of 100% by weight of aliphatic polyester, polybutylene adipate terephthalate (PBAT), and polyhydroxyalkanoate. As used herein, the term "polyhydroxyalkanoate" generally refers to a polyester derived from a hydroxyalkanoic acid monomer. Polyhydroxyalkanoates can be produced by a variety of microorganisms, including bacterial fermentation of sugars or lipids. Preferably, the hydroxyalkanoic acid is C4-C. 18Hydroxyalkylcarboxylic acids, preferably hydroxyalkylcarboxylic acids, contain 4-18 carbon atoms. More preferably, polyhydroxyalkyl esters contain monomer units having the following formula (I):

[0043] (I),

[0044] Where R is a variable with the formula C n H 2n +1 The alkyl group, and n, are integers from 1 to 15, preferably from 1 to 6. In some preferred embodiments, the polyhydroxyalkanoate is a homopolymer. In some preferred embodiments, the polyhydroxyalkanoate is a copolymer. When the polyhydroxyalkanoate is a copolymer, the copolymer may contain two different monomer units of formula (I). The term "polyhydroxyalkanoate" may also include a mixture of two or more different polyhydroxyalkanoates. The weight-average molecular weight (Mw) of the polyhydroxyalkanoate may be in the range of 70,000 to 1,000,000 g / mol, preferably in the range of 100,000 to 1,000,000 g / mol, more preferably in the range of 300,000 to 600,000 g / mol.

[0045] Illustrative examples of polyhydroxyalkanoates that can be used in this disclosure may include those selected from polyhydroxybutyrate, polyhydroxyvalerate, polyhydroxybutyrate-co-hydroxyhexanoate, and any combination thereof. Preferably, the polyhydroxyalkanoate is selected from poly-3-hydroxybutyrate (P3HB), poly-4-hydroxybutyrate (P4HB), poly-3-hydroxyvalerate (PHV), poly(3-hydroxybutyrate-co-4-hydroxybutyrate), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), and any combination thereof. More preferably, the polyhydroxyalkanoate is selected from poly-3-hydroxybutyrate (PHB).

[0046] ,

[0047] Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV)

[0048] ,and

[0049] Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH)

[0050] ,and

[0051] Any combination thereof. Even more preferably, the polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate. In a very preferred embodiment, the polyalkoxyalkanoate is poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). Preferably, the molar ratio m:n in the aforementioned structural formula is 95:5 to 85:15, more preferably 90:10 to 88:12. Preferably, the molar ratio of 3-hydroxyhexanoate used is 5-15 mol%, preferably 7-13 mol%, more preferably 10-13 mol% of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), each based on a total monomer content of 100 mol% in poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) is sold, for example, by P&G or Kaneka. The polyhydroxyalkanoate, particularly poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), can be obtained from renewable or fossil resources. Preferably, the polyhydroxyalkanoate is from a renewable resource. More preferably, a bio-based poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) can be used, which, for example, is available from Kaneka under the trade name AONILEX151A. Preferably, the polyhydroxyalkanoate is biodegradable. In particular, poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) is a biodegradable polyhydroxyalkanoate.

[0052] Preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the fiber contains 1 to 25% by weight of polyhydroxyalkanoate. More preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the fiber contains 2 to 22% by weight of polyhydroxyalkanoate. Even more preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the fiber contains 3 to 20% by weight of polyhydroxyalkanoate. Even more preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the fiber contains 3 to 18% by weight of polyhydroxyalkanoate. Even more preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the fiber contains 5 to 15% by weight of polyhydroxyalkanoate. Specifically, these ranges can be applied when the polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). Preferably, when the polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), the fiber contains 20% by weight or less, more preferably 18% by weight or less, of polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), based on aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), which is 100% by weight. If the proportion of polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) exceeds 18% by weight, it may become difficult to meet the biodegradability standard of EN 13432 without pre-composting or industrial composting, and this becomes even more difficult when it exceeds 20% by weight. In a preferred embodiment, the fiber contains 12% by weight of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), based on a total amount of 100% by weight of polybutylene succinate, butylene terephthalate adipate, and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). In a highly preferred embodiment, the aliphatic polyester is polybutylene succinate (PBS), the aliphatic-aromatic polyester is polybutylene terephthalate adipate (PBAT), and the polyalkoxyalkylene ester is poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). Therefore, in a highly preferred embodiment, the fibers comprise polybutylene succinate (PBS), polybutylene adipate terephthalate (PBAT), and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

[0053] The ranges of amounts of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate can also be combined with each other. Thus, as an illustrative example, the fiber may contain 42 to 62% by weight, preferably 45 to 55% by weight, of aliphatic polyester; the fiber may contain 26 to 46% by weight, preferably 30 to 40% by weight, of aliphatic-aromatic polyester; and the fiber may contain 2 to 22% by weight, preferably 3 to 20% by weight, more preferably 3 to 18% by weight, of polyhydroxyalkanoate, each based on 100% by weight of the total amount of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. Those skilled in the art will readily select suitable amounts of one or more polymers within the range provided herein, such that they do not exceed 100% by weight of the total amount of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. Specifically, these ranges can be applied when the aliphatic polyester is polybutylene succinate, the aliphatic aromatic polyester is polybutylene adipate terephthalate, and the polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). In a highly preferred embodiment, the fiber comprises 52% by weight of polybutylene succinate, 36% by weight of polybutylene adipate terephthalate, and 12% by weight of polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), each based on a total amount of 100% by weight of the polybutylene succinate, the polybutylene adipate terephthalate, and the polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

[0054] In some embodiments, polyhydroxyalkanoates may be partially or completely replaced by polylactide (PLA, also known as polylactic acid or poly(lactic acid)). Therefore, in some embodiments, when polyhydroxyalkanoates are partially replaced by polylactide, the fiber comprises aliphatic polyesters, aliphatic-aromatic polyesters, polyhydroxyalkanoates, and polylactide. In some embodiments, when polyhydroxyalkanoates are completely replaced by polylactide, the fiber comprises aliphatic polyesters, aliphatic-aromatic polyesters, and polylactide. However, in embodiments where polyhydroxyalkanoates are completely replaced by polylactide, the fiber does not contain polyhydroxyalkanoates.

[0055] Preferably, the fiber is a textile fiber. As used herein, the term "textile fiber" generally refers to a fiber suitable for the production of textiles. As an exemplary and non-limiting example, textile fibers may be suitable for preparing yarns, textiles, or textile surfaces.

[0056] Optionally, the fiber may further comprise at least one additive (or one or more additives). For example, the fiber may comprise at least one additive (or one or more additives) commonly known for use in textile fibers. Optional additives may include, but are not limited to, additives such as flame retardants, matting agents, markers for identification (e.g., fluorescent markers), antimicrobial agents, colorants, plasticizers, fillers, and any combination thereof.

[0057] Preferably, the fiber also contains a flame retardant, such as a phosphate. As used herein, the term "phosphate" refers to a substance containing a component selected from [H₂PO₄]. - [HPO4] 2- and [PO4] 3- A salt of an anion. Preferably, the cation is ammonium [NH4]. + Therefore, in a preferred embodiment, the flame retardant is selected from ammonium dihydrogen phosphate ([NH4][H2PO4]), diammonium hydrogen phosphate ([NH4]2[HPO4]), triammonium phosphate ([NH4]3[PO4]), and any combination thereof. More preferably, the flame retardant is selected from ammonium dihydrogen phosphate ([NH4][H2PO4]), diammonium hydrogen phosphate ([NH4]2[HPO4]), and any combination thereof. More preferably, the flame retardant is ammonium dihydrogen phosphate ([NH4][H2PO4]) or diammonium hydrogen phosphate ([NH4]2[HPO4]). More preferably, the flame retardant is diammonium hydrogen phosphate ([NH4]2[HPO4]). Alternatively, or additionally, the flame retardant may be a polyphosphate. A "polyphosphate" is a salt or ester of a polymeric oxyanion formed by tetrahedral PO4 (phosphate) structural units linked together by shared oxygen atoms. Preferably, when the flame retardant is a polyphosphate, the flame retardant is ammonium polyphosphate.

[0058] Based on a total fiber weight of 100% by weight, the fiber may contain 0.01 to 5% by weight of flame retardant. Preferably, based on a total fiber weight of 100% by weight, the fiber contains 0.1 to 4% by weight of flame retardant. More preferably, based on a total fiber weight of 100% by weight, the fiber contains 0.2 to 3% by weight of flame retardant. Even more preferably, based on a total fiber weight of 100% by weight, the fiber contains 0.3 to 3% by weight of flame retardant. Even more preferably, based on a total fiber weight of 100% by weight, the fiber contains 0.3 to 2% by weight of flame retardant. In particular, the above ranges can be applied when the flame retardant is a phosphate or polyphosphate, preferably when the flame retardant is diammonium hydrogen phosphate ([NH4]2[HPO4]).

[0059] Optionally, the fiber may (also) contain a matting agent. Any matting agent known to those skilled in the art can be used, such as typical matting agents used in fibers. As an illustrative example, the matting agent may be zinc sulfide.

[0060] Optionally, the fiber may also contain a marker suitable for identification. As an illustrative, non-limiting example, the marker suitable for identification may be a fluorescent marker. The fluorescence of the fiber can then be detected by a suitable device and used to identify the fiber. For example, fluorescent markers available from Polysecure, Freiburg im Breisegau, Germany can be used. The marker suitable for identification is typically used only in small amounts and generally does not alter the properties of the fiber. Typically, the amount of the marker suitable for identification in the fiber is in the range of ppb (parts per billion).

[0061] Optionally, the fiber may (also) include an antimicrobial agent. Any antimicrobial agent known to those skilled in the art and suitable for fibers may be used. As an illustrative, non-limiting example, the antimicrobial agent may be zinc encapsulated in polyethylene terephthalate. Such an antimicrobial agent, for example, may be commercially available from SmartPolymer GmbH of Rudolstadt, Germany, under the trade name SMARTZINC 213 PET hot melt.

[0062] Optionally, the fiber may (also) include a plasticizer. Any plasticizer known to those skilled in the art and suitable for use in fibers may be used. As an illustrative example, the plasticizer may be polycaprolactone. In particular, polycaprolactone is biodegradable. In some embodiments, based on 100% by weight of the total fiber weight, the fiber may contain 1% by weight or less of polycaprolactone. Fibers containing 1% by weight or less of polycaprolactone have been shown to exhibit satisfactory softness and flexibility. However, it should be noted that fibers according to the invention comprising aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates generally exhibit satisfactory softness and flexibility without the addition of polycaprolactone or other plasticizers.

[0063] Optionally, the fiber may (and may also) include a colorant. Any colorant suitable for the fiber that provides the desired color can be used. As an illustrative example, the colorant may be an inorganic or organic pigment.

[0064] Optionally, the fibers may (and may also) include fillers. Any filler known to those skilled in the art suitable for use with fibers can be used, preferably a biodegradable filler. As an illustrative example, the (biodegradable) filler may be lignin or may include lignin. Preferably, the lignin is oxygen-bleached lignin. Oxygen bleaching of lignin is an environmentally friendly method compared to conventional chlorine bleaching.

[0065] Those skilled in the art will readily select the appropriate amount of additives to be included in the fiber. As an illustrative example, the fiber may contain 15% by weight or less of the total additives based on 100% by weight of the total fiber weight. The fiber may contain 10% by weight or less of the total additives based on 100% by weight of the total fiber weight. Preferably, the fiber contains 7% by weight or less of the total additives based on 100% by weight of the total fiber weight. More preferably, the fiber contains 5% by weight or less of the total additives based on 100% by weight of the total fiber weight. Even more preferably, the fiber contains a total of 4% by weight or less of the additives based on 100% by weight of the total fiber weight. Even more preferably, the fiber contains 3 to 4% by weight of the total additives based on 100% by weight of the total fiber weight. Preferably, the fiber contains a total of 7% by weight or less, more preferably 3 to 4% by weight of the additives, each based on 100% by weight of the total fiber weight, in order to achieve a fiber stiffness suitable for use in textile fibers. There are no particular limitations on the fiber fineness. For example, any fiber fineness commonly used in the textile industry can be applied. As an illustrative example, the fiber fineness can be from 0.5 to 8 denier. Preferably, the fiber fineness is from 0.8 to 6 denier. More preferably, the fiber fineness is from 0.9 to 3 denier. Even more preferably, the fiber fineness is from 1.0 to 2 denier. Still more preferably, the fiber fineness is from 1.0 to 1.5 denier. Even more preferably, the fiber fineness is from 1.1 to 1.2 denier.

[0066] The fiber can be a short fiber. As used herein, the term "short fiber" generally refers to a fiber of discrete length. There is no particular limitation on the length of the short fiber. For example, any short fiber length commonly used in the textile industry can be used. Thus, as an illustrative example, the fiber may have a short fiber length of 2 to 80 mm. Preferably, the fiber has a short fiber length of 5 to 70 mm. More preferably, the fiber has a short fiber length of 10 to 60 mm. Even more preferably, the fiber has a short fiber length of 15 to 50 mm. Even more preferably, the fiber has a short fiber length of 20 to 40 mm. Even more preferably, the fiber has a short fiber length of 22 to 35 mm. Even more preferably, the fiber has a short fiber length of 25 to 32 mm. The term "short fiber length" generally refers to the average length of the fibers in the sample.

[0067] Fibers can be filaments. The terms "filament" or "filament fiber" generally refer to fibers that are virtually of unlimited length. Therefore, the terms "filament" or "filament fiber" generally refer to continuous fibers.

[0068] Preferably, the fiber is biodegradable. More preferably, the fiber is biodegradable according to EN 13432. Therefore, a fiber can be considered biodegradable according to EN 13432 when it has a biodegradation percentage equal to at least 90% of DIN EN 13432 after a specified period of time. A general effect of biodegradability is that the fiber decomposes within an appropriate and verifiable time interval. Degradation can be achieved by enzymatic, hydrolytic, oxidative, and / or by the action of electromagnetic radiation such as UV radiation, and can be primarily due to the action of microorganisms such as bacteria, yeast, fungi, and algae. For example, biodegradability can be quantified by mixing the fiber with compost and storing it for a certain period of time. For example, during composting, CO2-free air can flow through the maturing compost, and the maturing compost undergoes a defined temperature program. Biodegradability can be defined, for example, as the percentage degree of biodegradation by the ratio of the net CO2 released by the sample (after deducting the CO2 released by compost without the sample) to the maximum amount of CO2 that the sample can release (calculated from the carbon content of the sample). Biodegradable fibers typically show clear signs of degradation, such as fungal growth, cracking, and pore formation, just days after composting. Other methods for determining biodegradability are described, for example, in ASTM D 5338 and ASTM D 6400.

[0069] Preferably, the fiber is a crimped fiber.

[0070] Optionally, any fiber described herein may be post-processed, for example using a fiber post-processing production line. Post-processing may include steps typically used to process fibers, such as reeding, introducing a structure, impregnation, drafting, stretching, steaming, recovery, crimping, drying, and / or short fiber cutting.

[0071] In some embodiments, the fiber is not a hollow fiber. As used herein and known in the art, the term "hollow fiber" generally refers to any fiber having one or more cavities in its cross-section. As used herein, the term "cavity" generally refers to a hollow space present within the cross-section of the fiber. The cavity may be filled with a gas, such as air. As an exemplary example, the cross-section of a hollow fiber may have a single continuous cavity. However, a hollow fiber may also include more than one cavity (e.g., 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, or even more cavities). In addition to one or more cavities, a hollow fiber may also include one or more portions having a dense structure. As used herein, the term "dense structure" may also be referred to as "compact structure," generally indicating that the fibrous material exists in a substantially dense or compact form, particularly when compared to the cavities of a hollow fiber. The terms "dense structure" or "compact structure" may also include structures containing pores, however, these pores are typically significantly smaller than the cavities of the hollow fiber. Hollow fibers that include both cavities and dense (or compact) structures may also be referred to as segmented fibers or segmented hollow fibers. As an exemplary example, a hollow fiber may include cavities and dense structures arranged in an alternating pattern along the longitudinal direction of the fiber.

[0072] Specifically, in some embodiments, the fiber is not the fiber described in International Patent Application PCT / EP2022 / 075084. The fiber described in PCT / EP2022 / 075084 is also described below. Therefore, in some embodiments, the fiber is not:

[0073] Fibers obtained by a method including the following steps or by a method including the following steps:

[0074] - The melts of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates are spun through hollow fiber spinning nozzles to obtain precursor fibers; and

[0075] - The precursor fiber is obtained by cooling it under a temperature gradient.

[0076] The fiber that can be obtained or acquired by this method comprises two parts, one being a thicker portion and the other a thinner portion, and has the structure described below. Therefore, in some embodiments, the fiber is not:

[0077] - Fibers made from a mixture of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates.

[0078] The fiber comprises two parts in the longitudinal direction: a thicker part and a thinner part. The thicker part and the thinner part extend in the vertical direction relative to the longitudinal direction of the fiber, and the extension of the thicker part in the vertical direction is greater than that of the thinner part in the vertical direction.

[0079] In this embodiment, at least a portion of the thicker portion has a cavity, and at least a portion of the thinner portion has a compact structure. In some embodiments, the fiber is not:

[0080] Hollow fibers made from a mixture comprising aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates. In some embodiments, the fibers are not segmented fibers or segmented hollow fibers.

[0081] In some embodiments, the fiber is a solid fiber. In some embodiments, the fiber is a non-hollow fiber. As used herein and known in the art, the term "solid fiber" or also referred to as "non-hollow fiber" generally refers to any fiber in which the fibrous material exists in a substantially dense or compact form and does not have cavities, as described herein with respect to hollow fibers. However, the terms "solid fiber" or "non-hollow fiber" do not preclude the fiber from containing a few pores; however, these pores are generally significantly smaller than the cavities of hollow fibers.

[0082] This invention also relates to yarns comprising the fibers described herein. Any type of yarn can be contemplated. By way of non-illustrative example, the yarn can be a fine yarn, carded or combed yarn, knitted yarn, air-jet yarn, fancy yarn, filament yarn, or textured yarn. The yarn can be prepared from the fibers described herein by any method suitable for yarn preparation. Methods for yarn preparation are generally known and readily chosen by those skilled in the art.

[0083] The present invention also relates to textile surfaces comprising the fibers described herein. The present invention also relates to textile surfaces comprising yarns comprising the fibers as described herein. As an illustrative, non-limiting example, the textile surface may be selected from woven fabrics, knitted fabrics, and nonwoven fabrics. Fibers or yarns comprising fibers may also be used to produce wool. The present invention also relates to textiles comprising the fibers as described herein. The present invention also relates to textiles comprising yarns comprising the fibers described herein. The textile may be clothing. As an illustrative, non-limiting example, clothing may be selected from shirts, polo shirts, trousers, jackets, underwear, socks, coats, shoes, and shoelaces. In particular, the clothing may be shirts or polo shirts, preferably shirts. The textile may be home textiles. As an illustrative, non-limiting example, home textiles may be selected from curtains, carpets, blankets, sheets, comforters, duvet covers, mattresses, mattress protectors, and towels.

[0084] The present invention also relates to a method for preparing fibers according to the present invention, comprising:

[0085] - By spinning melts of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates through a spinning nozzle, precursor fibers are obtained; and

[0086] - Cool the precursor fibers to obtain the fibers. The fibers may be further defined as described herein for any fiber.

[0087] As used herein, the term "precursor fiber" generally refers to the fiber that appears as an intermediate during the manufacturing process of this invention, after exiting the spinning nozzle and during cooling. The (final) fiber of this invention, obtained by this method or obtained by this method, especially after cooling, is generally referred to simply as "fiber".

[0088] The melt for spinning fibers can be produced using any method known to those skilled in the art for producing melts of spun fibers. As an illustrative example, aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates can be mixed in a non-molten state, for example, by mixing polymer particles, optionally with one or more other additives. Optionally, the polymer and (if present) additives can be dried before mixing and preparing the melt. Then, to prepare the melt, the mixture can be heated to the melting point of the polymer or above. As an illustrative example, mixing and heating can be carried out in an extruder. In some embodiments, the temperature of the melt, particularly before spinning through a spinning nozzle, can be 200°C-260°C, preferably 220°C-250°C, more preferably 230°C-250°C, and even more preferably 230°C-240°C. As an illustrative example, the melt can be heated to a temperature of 235°C and then passed through a spinning nozzle. As an illustrative example, an extruder can be used to pass the melt through a hollow fiber spinning nozzle. Any spinning nozzle commonly known in the art can be used. A hot precursor fiber is obtained by spinning a melt containing aliphatic polyester, aliphatic aromatic polyester, and polyhydroxyalkanoate through a spinning nozzle. The hot precursor fiber obtained by spinning the melt through the spinning nozzle is then cooled to obtain the fiber.

[0089] Cooling of the precursor fibers can be achieved by using any suitable cooling device / equipment. Those skilled in the art can readily select a suitable device / equipment for cooling. For example, one or more temperature control elements can be used for cooling. As an illustrative example, the temperature control element may be arranged and / or operated within or near the spinning apparatus. Equipment for melt spinning is generally known to those skilled in the art. The temperature control element may be a heating and / or cooling element that can actively or passively provide a heating or cooling effect to the precursor fibers. An exemplary, and not limiting, example of a temperature control element as a cooling element is an air cooling aggregate that provides an airflow onto the precursor fibers. For example, the air cooling aggregate may be arranged on the side of the precursor fibers, which provides an airflow in a direction substantially perpendicular to the longitudinal direction of the precursor fibers; see, for example, […]. Figure 1 The precursor fiber 3 and airflow 7, by arranging cooling aggregates on both sides of the precursor fiber, allow cooling of the precursor fiber to occur with a substantially uniform temperature distribution within the fiber. The air used for air cooling can have an ambient temperature, preferably room temperature, more preferably +20°C + / -5°C. However, although air cooling using cooling aggregates is shown... Figure 1 However, air cooling can also be achieved by simply exposing the precursor fibers to ambient air, i.e., without providing airflow from the cooling aggregate to the precursor fibers. Any other suitable cooling device, such as water cooling, can also be used.

[0090] In some implementations, cooling is achieved through air cooling.

[0091] Preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the melt contains 30 to 70% by weight of aliphatic polyester. More preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the melt contains 35 to 65% by weight of aliphatic polyester. Even more preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the melt contains 40 to 60% by weight or 42 to 62% by weight of aliphatic polyester. Even more preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the melt contains 45 to 55% by weight of aliphatic polyester. In particular, these ranges can be applied when the aliphatic polyester is polybutylene succinate. In a preferred embodiment, based on a total amount of 100% by weight of polybutylene succinate, aliphatic aromatic polyester and polyhydroxyalkanoate, the melt contains 52% by weight of polybutylene succinate.

[0092] Preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the melt contains 10 to 60% by weight of aliphatic-aromatic polyester. More preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the melt contains 20 to 50% by weight of aliphatic-aromatic polyester. Even more preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the melt contains 25 to 40% by weight or 26 to 46% by weight of aliphatic-aromatic polyester. Even more preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the melt contains 30 to 40% by weight of aliphatic-aromatic polyester. In particular, these ranges can be applied when the aliphatic-aromatic polyester is polybutylene terephthalate (PBAT). In a preferred embodiment, based on a total amount of 100% by weight of aliphatic polyester, polybutylene terephthalate (PBAT), and polyhydroxyalkanoate, the melt contains 36% by weight of polybutylene terephthalate (PBAT).

[0093] Preferably, based on a 100% by weight total amount of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the melt contains 1 to 25% by weight of polyhydroxyalkanoate. More preferably, based on a 100% by weight total amount of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the melt contains 2 to 22% by weight of polyhydroxyalkanoate. Even more preferably, based on a 100% by weight total amount of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the melt contains 3 to 20% by weight of polyhydroxyalkanoate. Even more preferably, based on a 100% by weight total amount of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the melt contains 3 to 18% by weight of polyhydroxyalkanoate. Even more preferably, based on a 100% by weight total amount of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the melt contains 5 to 15% by weight of polyhydroxyalkanoate. Specifically, these ranges can be applied when the polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). Preferably, when the polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), the total amount of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) is 100% by weight, and the melt contains 20% by weight or less, more preferably 18% by weight or less of polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

[0094] The ranges of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates can also be combined with each other. Thus, as an illustrative example, the melt may contain 42 to 62% by weight, preferably 45 to 55% by weight, of aliphatic polyester; the melt may contain 26 to 46% by weight, preferably 30 to 40% by weight, of aliphatic-aromatic polyester; and the melt may contain 2 to 22% by weight, preferably 3 to 20% by weight, more preferably 3 to 18% by weight, of polyhydroxyalkanoates, each based on a total amount of 100% by weight of the aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoates. Those skilled in the art will readily select suitable amounts of one or more polymers within the ranges provided herein, such that they do not exceed 100% by weight of the total amount of the aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoates. Specifically, these ranges can be applied when the aliphatic polyester is polybutylene succinate, the aliphatic aromatic polyester is polybutylene adipate terephthalate, and the polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). In a very preferred embodiment, the melt comprises 52 wt% polybutylene succinate, 36 wt% polybutylene adipate terephthalate, and 12 wt% polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), each based on a total of 100 wt% polybutylene succinate, polybutylene adipate terephthalate, and polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

[0095] In some embodiments, polyhydroxyalkanoates may be partially or completely replaced by polylactide (PLA, also known as polylactic acid or poly(lactic acid)). Therefore, in some embodiments, when polyhydroxyalkanoates are partially replaced by polylactide, the melt comprises aliphatic polyesters, aliphatic-aromatic polyesters, polyhydroxyalkanoates, and polylactide. In some embodiments, when polyhydroxyalkanoates are completely replaced by polylactide, the melt comprises aliphatic polyesters, aliphatic-aromatic polyesters, and polylactide. However, in embodiments where polyhydroxyalkanoates are completely replaced by polylactide, the melt does not contain polyhydroxyalkanoates.

[0096] Optionally, the melt may further comprise at least one additive. For example, the melt may comprise at least one additive commonly known for use in textile fibers. Optional additives may include, but are not limited to, additives selected from flame retardants, matting agents, identification markers (e.g., fluorescent markers), antimicrobial agents, plasticizers, colorants, fillers, and any combination thereof.

[0097] Preferably, the melt further comprises a flame retardant. More preferably, the flame retardant is a phosphate. In a preferred embodiment, the flame retardant is selected from ammonium dihydrogen phosphate ([NH4][H2PO4]), diammonium hydrogen phosphate ([NH4]2[HPO4]), triammonium phosphate ([NH4]3[PO4]), and any combination thereof. More preferably, the flame retardant is selected from ammonium dihydrogen phosphate ([NH4][H2PO4]), diammonium hydrogen phosphate ([NH4]2[HPO4]), and any combination thereof. More preferably, the flame retardant is ammonium dihydrogen phosphate ([NH4][H2PO4]) or diammonium hydrogen phosphate ([NH4]2[HPO4]). More preferably, the flame retardant is diammonium hydrogen phosphate ([NH4]2[HPO4]). Alternatively or additionally, the flame retardant may be a polyphosphate. Preferably, when the flame retardant is a polyphosphate, the flame retardant is ammonium polyphosphate.

[0098] The melt may contain 0.01 to 5% by weight of flame retardant, based on 100% by weight of the total weight of the melt. Preferably, the melt contains 0.1 to 4% by weight of flame retardant, based on 100% by weight of the total weight of the melt. More preferably, the melt contains 0.2% to 3% by weight of flame retardant, based on 100% by weight of the total weight of the melt. Even more preferably, the melt contains 0.3% to 3% by weight of flame retardant, based on 100% by weight of the total weight of the melt. Even more preferably, the melt contains 0.3% to 2% by weight of flame retardant, based on 100% by weight of the total weight of the melt. In particular, the above ranges can be applied when the flame retardant is a phosphate or polyphosphate, preferably when the flame retardant is diammonium hydrogen phosphate ([NH4]2[HPO4]).

[0099] Those skilled in the art will readily select the appropriate amount of additives contained in the melt. As an illustrative example, based on a total melt weight of 100% by weight, the melt may contain a total of 15% by weight or less of additives. Based on a total melt weight of 100% by weight, the melt may contain a total of 10% by weight or less of additives. Preferably, based on a total melt weight of 100% by weight, the melt contains a total of 7% by weight or less of additives. More preferably, based on a total melt weight of 100% by weight, the melt contains a total of 5% by weight or less of additives. Even more preferably, based on a total melt weight of 100% by weight, the melt contains a total of 4% by weight or less of additives. Even more preferably, based on a total melt weight of 100% by weight, the melt contains a total of 3 to 4% by weight of additives. Preferably, the melt contains a total of 7% by weight or less, more preferably 3-4% by weight of additives, each based on a total melt weight of 100% by weight, to obtain stiffness suitable for use in textile fibers.

[0100] The fiber can be prepared as a short fiber.

[0101] The fiber can be prepared into a filament.

[0102] In some embodiments, the spinning nozzle is not a hollow fiber spinning nozzle. As used herein, the term "hollow fiber spinning nozzle" refers to any hollow fiber spinning nozzle commonly known in the art. Illustrative examples of hollow fiber spinning nozzles are described, for example, in EP 2 112 256, the entire contents of which are incorporated herein by reference.

[0103] In some embodiments, the method is not the method for preparing fibers as described in International Patent Application PCT / EP2022 / 075084. Specifically, in some embodiments, the method is not:

[0104] A method for preparing fibers, comprising:

[0105] - Melts of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates are spun through hollow fiber spinning nozzles to obtain precursor fibers; and

[0106] - The precursor fiber is obtained by cooling it under a temperature gradient.

[0107] The present invention also relates to fibers that can be obtained or obtained by a method for preparing fibers according to the present invention.

[0108] The present invention also relates to the use of melts comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates for the preparation of fibers, wherein the fibers are as defined herein.

[0109] The present invention also relates to the use of melts comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates for the preparation of fibers.

[0110] Filaments suitable for 3D printing

[0111] The present invention also relates to a filament suitable for 3D printing, said filament being made of a mixture comprising aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate.

[0112] It has been found that mixtures comprising aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates are highly suitable for preparing filaments that can be used for 3D printing. In particular, filaments comprising aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates can be obtained by extruding a melt containing aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates into a filament shape, or by extruding the melt into a filament shape. In this respect, mixtures comprising aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates have been found to exhibit good extrudability, particularly good performance in extruding into filaments. As another advantage, as shown with respect to the fibers of the present invention (see Example 2), filaments suitable for 3D printing can be produced without toxic substances (e.g., antimony). Furthermore, by using aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates, filaments suitable for 3D printing can be obtained that are biodegradable, even meeting the harmonized European standard EN 13432, and therefore can be disposed of in industrial composting plants. It has also been demonstrated that the filaments of the present invention, comprising aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates, are highly suitable for producing 3D printed articles using conventional 3D printers, such as those operating under material extrusion technology. Therefore, 3D printed articles that are also biodegradable and even meet the harmonized European standard EN 13432 can be prepared from the filaments suitable for 3D printing according to the present invention. It should be noted that various products, such as sheets and foils, and fibers comprising one or more of aliphatic polyesters, aliphatic-aromatic polyesters, and / or polyhydroxyalkanoates, are described in, for example, EP3626767, WO 2010 / 034689, WO 2010 / 034711, WO 2015 / 169660, EP1966419, EP2984138, CN103668540, CN 103668541, WO 2014 / 173055, and CN 104120502.

[0113] As used in this field, 3D printing, also known as “3D printing” or “additive manufacturing,” generally refers to constructing three-dimensional objects, for example, from CAD models or digital 3D models. It can be accomplished in various processes where materials are deposited, bonded, or cured under computer control, typically added together layer by layer (e.g., plastics, liquids, or powder particles are melted). Currently, various additive manufacturing technologies (e.g., binder jetting, material extrusion, and photopolymerization) are available on the market for 3D printers (hereinafter sometimes referred to as “3D printers”). Among these, 3D printer systems based on material extrusion technology (e.g., systems manufactured by Stratasys) are used to construct three-dimensional objects layer by layer from computer-aided design (CAD) models by extruding flowable raw materials from nozzle components located at the extrusion head. This system is an illustrative example of a simple system in which a filament comprising a raw material made of thermoplastic resin is inserted into an extruder head and continuously extruded from a nozzle portion disposed on the extruder head into an XY-plane platform within a chamber while being heated and melted. The extruded resin deposits on and fuses with a pre-formed resin deposit, and solidifies to become integral with the resin deposit as the extruded resin cools. In material extrusion methods, the extrusion step is typically repeated as the nozzle rises relative to the platform in the Z-axis direction perpendicular to the XY plane, thereby constructing a three-dimensional object similar to a CAD model. The filament suitable for 3D printing according to the invention can be used to prepare 3D printed articles using, for example, material extrusion techniques.

[0114] The filaments suitable for 3D printing of the present invention may be further defined as described herein with respect to any fiber of the present invention.

[0115] As used herein, the term "aliphatic polyester" generally refers to polyesters typically synthesized via the polycondensation reaction of aliphatic diols with aliphatic dicarboxylic acids or their anhydrides. As an illustrative example, the aliphatic polyester used herein may contain aliphatic C2-C... 20 Dicarboxylic acids and aliphatic C2-C 12 Diol. Preferably, the aliphatic diol is an aliphatic C2-C8 diol. More preferably, the aliphatic diol is an aliphatic C2-C6 diol. Even more preferably, the aliphatic diol is an aliphatic C3 or aliphatic C4 diol. As an illustrative example, the aliphatic diol used in aliphatic polyesters may include ethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, and 1,6-hexanediol. Preferably, the aliphatic diol is 1,3-propanediol or 1,4-butanediol. More preferably, the aliphatic diol is 1,4-butanediol. Preferably, the aliphatic dicarboxylic acid is an aliphatic C2-C6 diol. 12Dicarboxylic acid. More preferably, the aliphatic dicarboxylic acid is an aliphatic C2-C8 dicarboxylic acid, and even more preferably an aliphatic C4 dicarboxylic acid. As an illustrative example, the aliphatic dicarboxylic acid used in the aliphatic polyester may include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, etc. Preferably, the aliphatic dicarboxylic acid is malonic acid or succinic acid. More preferably, the aliphatic dicarboxylic acid is succinic acid. Optionally, when the dicarboxylic acid is an aliphatic C2-C8 dicarboxylic acid... 12 When dicarboxylic acids are used, aliphatic polyesters may further contain components different from C2-C. 12 Other aliphatic C6-C dicarboxylic acids 20 Dicarboxylic acid. Optional aliphatic C6-C 12 Dicarboxylic acids may include, as illustrative examples, adipic acid, octanoic acid, azelaic acid, sebacic acid, brassic acid, and arachidonic acid. Preferably, optionally, aliphatic C6-C... 12 Dicarboxylic acids may include adipic acid, octanoic acid, azelaic acid, sebacic acid, and brassic acid. Based on the total amount of aliphatic dicarboxylic acids in the aliphatic polyester being 100 mol%, optionally aliphatic C2-C... 12 Dicarboxylic acids may be present in the aliphatic polyester at a ratio of 0-10 mol%. Optionally, the aliphatic polyester may further comprise chain extenders and / or branching agents. As illustrative examples, optional chain extenders and / or branching agents may include polyfunctional isocyanates, isocyanurates, oxazolines, carboxylic anhydrides such as maleic anhydride, epoxides (particularly epoxy-containing poly(meth)acrylates), at least ternary alcohols, and at least ternary carboxylic acids. Optional chain extenders and / or branching agents may be present in the aliphatic polyester at a ratio of 0 to 1 wt% based on a total aliphatic dicarboxylic acid and aliphatic diol of 100 wt%. The term "aliphatic polyester" may also include mixtures of two or more different aliphatic polyesters. The number-average molecular weight (Mn) of the aliphatic polyester can be from 2,500 to 150,000 g / mol, preferably from 5,000 to 100,000 g / mol, more preferably from 7,500 to 75,000 g / mol, even more preferably from 10,000 to 65,000 g / mol, and even more preferably from 12,000 to 60,000 g / mol. The weight-average molecular weight (Mw) of the aliphatic polyester can be from 5,000 to 300,000 g / mol, preferably from 10,000 to 250,000 g / mol, more preferably from 20,000 to 220,000 g / mol, even more preferably from 50,000 to 200,000 g / mol, and even more preferably from 60,000 to 190,000 g / mol. The polydispersity index (i.e., the ratio of weight-average molecular weight to number-average molecular weight (Mw / Mn)) of the aliphatic polyester can be 1 to 6, preferably 1 to 4, more preferably 1.0 to 3.0, even more preferably 1.2 to 2.0, and even more preferably 1.4 to 1.8.

[0116] Illustrative examples of aliphatic polyesters that can be used in this invention may include aliphatic polyesters selected from the following: polybutylene succinate (PBS), polyethylene oxalate, polyethylene malonate, polyethylene succinate, polypropylene oxalate, polypropylene malonate, polypropylene oxalate, polybutylene malonate, polybutylene malonate, polybutylene-co-adipate (PBSA), polybutylene-co-azelate (PBSAz), polybutylene-co-brasinate (PBSBr), and any combination thereof. The aliphatic polyester may preferably be selected from polybutylene succinate (PBS), polybutylene-co-adipate (PBSA), polybutylene-co-azelate (PBSAz), polybutylene-co-brasinate (PBSBr), and any combination thereof. In a preferred embodiment, the aliphatic polyester is polybutylene succinate. As used herein, the term "polybutylene succinate" specifically refers to the condensation product of aliphatic dicarboxylic acid succinic acid and aliphatic diol 1,4-butanediol. Aliphatic polyesters polybutylene succinate (PBS) and polybutylene co-succinate (PBSA) are commercially available, for example, from Showa Highpolymer under the brand name Blanche. ® Obtained by Mitsubishi with GSPIa ® The aliphatic polyester, particularly polybutylene succinate (PBS), can be obtained from renewable or fossil resources. Preferably, an aliphatic polyester from a renewable resource is used. More preferably, a bio-based polybutylene succinate (PBS) produced from bio-based succinic acid and 1,4-butanediol can be used, which is, for example, commercially available under the trade name BioPBSTM FZ71 from Mitsubishi Chemicals. Preferably, the aliphatic polyester is biodegradable. In particular, polybutylene succinate (PBS) is a biodegradable aliphatic polyester.

[0117] Preferably, the filament suitable for 3D printing comprises 30 to 70% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, based on a total amount of 100% by weight. More preferably, the filament comprises 35 to 65% by weight of aliphatic polyester, based on a total amount of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. Even more preferably, the filament comprises 40 to 60% by weight or 42 to 62% by weight of aliphatic polyester, based on a total amount of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. Even more preferably, the filament comprises 45 to 55% by weight of aliphatic polyester, based on a total amount of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. In particular, these ranges can be applied when the aliphatic polyester is polybutylene succinate. In a preferred embodiment, the filament comprises 52% by weight of polybutylene succinate, aliphatic aromatic polyester and polyhydroxyalkanoate, based on a total amount of 100% by weight.

[0118] As used herein, the term "aliphatic-aromatic polyester" generally refers to polyesters typically synthesized from aliphatic diols, aliphatic dicarboxylic acids, and aromatic dicarboxylic acids. As an illustrative example, aliphatic-aromatic polyesters may contain aliphatic C2-C... 20 Dicarboxylic acids, aromatic dicarboxylic acids, and aliphatic C2-C 12 Alcohols. Preferably, the aliphatic diol is an aliphatic C2-C8 diol. More preferably, the aliphatic diol is an aliphatic C2-C6 diol. Even more preferably, the aliphatic diol is an aliphatic C3 or aliphatic C4 diol. As an illustrative example, the aliphatic diol used in aliphatic-aromatic polyesters may include ethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, and 1,6-hexanediol. Preferably, the aliphatic diol is 1,3-propanediol or 1,4-butanediol. More preferably, the aliphatic diol is 1,4-butanediol. Preferably, the aliphatic dicarboxylic acid is an aliphatic C2-C6 diol. 12 Dicarboxylic acids. More preferably, aliphatic dicarboxylic acids are aliphatic C4-C. 10Dicarboxylic acids, and even more preferably aliphatic C6 dicarboxylic acids. As illustrative examples, aliphatic dicarboxylic acids used in aliphatic-aromatic polyesters may include glutaric acid, adipic acid, pimelic acid, azelaic acid, sebacic acid, brassic acid, octanoic acid, and itaconic acid. Preferably, the aliphatic dicarboxylic acid is adipic acid, azelaic acid, or sebacic acid. More preferably, the aliphatic dicarboxylic acid is adipic acid. Preferably, the aromatic dicarboxylic acid is terephthalic acid. Aromatic dicarboxylic acids, particularly terephthalic acid, may be present in the aliphatic-aromatic polyester in amounts, for example, 30-70 mol%, preferably 40-60 mol%, more preferably 40-55 mol%, each based on 100 mol% of the total amount of aliphatic and aromatic dicarboxylic acids. Optionally, the aliphatic polyester may further comprise chain extenders and / or branching agents. Optional chain extenders may include, as illustrative examples, di- or polyfunctional isocyanates, preferably hexamethylene diisocyanate. Optional branching agents may include, as illustrative examples, trimethylolpropane, pentaerythritol, and preferably glycerol. Optional chain extenders and / or branching agents may be present in the aliphatic polyester at a ratio of 0 to 1% by weight, based on a total amount of aliphatic dicarboxylic acids, aromatic dicarboxylic acids, and aliphatic diols of 100% by weight. The term "aliphatic-aromatic polyester" may also include mixtures of two or more different aliphatic-aromatic polyesters. The number-average molecular weight (Mn) of the aliphatic-aromatic polyester may be from 1,000 to 500,000 g / mol, preferably from 5,000 to 300,000 g / mol, more preferably from 5,000 to 100,000 g / mol, even more preferably from 10,000 to 75,000 g / mol, and even more preferably from 15,000 to 50,000 g / mol. The weight-average molecular weight (Mw) of the aliphatic-aromatic polyester can be from 10,000 to 500,000 g / mol, preferably from 20,000 to 400,000 g / mol, more preferably from 30,000 to 300,000 g / mol, and even more preferably from 60,000 to 200,000 g / mol. The polydispersity index (i.e., the ratio of weight-average molecular weight to number-average molecular weight (Mw / Mn)) of the aliphatic-aromatic polyester can be from 1 to 6, preferably from 2 to 4, more preferably from 1.0 to 3.0, even more preferably from 1.2 to 2.0, and even more preferably from 1.4 to 1.8.

[0119] The aliphatic-aromatic polyesters that can be used in this invention may include, but are not limited to, aliphatic-aromatic polyesters selected from the following: polybutylene terephthalate adipate (PBAT), polybutylene terephthalate succinate (PBST), polybutylene terephthalate sebacic acid (PBSeT), and any combination thereof. In a preferred embodiment, the aliphatic-aromatic polyester is polybutylene terephthalate adipate (PBAT). The term "polybutylene terephthalate adipate" as used herein refers to an aliphatic-aromatic polyester comprising aliphatic dicarboxylic acid adipic acid, aromatic dicarboxylic acid terephthalic acid, and aliphatic diol 1,4-butanediol. Aliphatic-aromatic polyesters, particularly polybutylene terephthalate adipate (PBAT), can be obtained from renewable or fossil resources. Preferably, aliphatic-aromatic polyesters from renewable resources are used. Polybutylene terephthalate adipate (PBAT) is, for example, produced by BASF using Ecoflex. ® Sales, such as Ecoflex ® F Blend C1200 or Ecoflex ® FBX7011, or by Showa Denko with Bionolle ® For sale. Preferably, the aliphatic-aromatic polyester is biodegradable. In particular, polybutylene terephthalate (PBAT) is a biodegradable aliphatic-aromatic polyester.

[0120] Preferably, based on a total amount of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the filament suitable for 3D printing contains 10 to 60% by weight of aliphatic-aromatic polyester. More preferably, based on a total amount of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the filament contains 20 to 50% by weight of aliphatic-aromatic polyester. Even more preferably, based on a total amount of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the filament contains 25 to 40% by weight or 26 to 46% by weight of aliphatic-aromatic polyester. Even more preferably, based on a total amount of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the filament contains 30 to 40% by weight of aliphatic-aromatic polyester. In particular, these ranges can be applied when the aliphatic-aromatic polyester is polybutylene terephthalate (PBAT). In a preferred embodiment, based on a total of 100% by weight of aliphatic polyester, polybutylene terephthalate (PBAT), and polyhydroxyalkanoate, the filament comprises 36% by weight of polybutylene terephthalate (PBAT). As used herein, the term "polyhydroxyalkanoate" generally refers to a polyester derived from a hydroxyalkanoic acid monomer. Polyhydroxyalkanoates can be produced by a variety of microorganisms, including bacterial fermentation of sugars or lipids. Preferably, the hydroxyalkanoic acid is C4-C. 18Hydroxyalkylcarboxylic acids, preferably hydroxyalkylcarboxylic acids, contain 4-18 carbon atoms. More preferably, polyhydroxyalkyl esters contain monomer units having the following formula (I):

[0121] (I),

[0122] Where R is a variable with the formula C n H 2n +1 The alkyl group and n are integers of 1-15, preferably 1-6. In some embodiments, the polyhydroxyalkanoate is a homopolymer. In some preferred embodiments, the polyhydroxyalkanoate is a copolymer. When the polyhydroxyalkanoate is a copolymer, the copolymer may contain two different monomer units of formula (I). The term "polyhydroxyalkanoate" may also include a mixture of two or more different polyhydroxyalkanoates. The weight-average molecular weight (Mw) of the polyhydroxyalkanoate may be in the range of 70,000 to 1,000,000 g / mol, preferably in the range of 100,000 to 1,000,000 g / mol, more preferably in the range of 300,000 to 600,000 g / mol.

[0123] Illustrative examples of polyhydroxyalkanoates that can be used in this disclosure may include polyhydroxyalkanoates selected from: polyhydroxybutyrate, polyhydroxyvalerate, polyhydroxybutyrate-co-hydroxyhexanoate, and any combination thereof. Preferably, the polyhydroxyalkanoate is selected from poly-3-hydroxybutyrate (P3HB), poly-4-hydroxybutyrate (P4HB), poly-3-hydroxyvalerate (PHV), poly(3-hydroxybutyrate-co-4-hydroxybutyrate), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), and any combination thereof. More preferably, the polyhydroxyalkanoate is selected from poly-3-hydroxybutyrate (PHB).

[0124] ,

[0125] Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV)

[0126] ,and

[0127] Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH)

[0128] ,and

[0129] Any combination thereof. Even more preferably, the polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate. In a very preferred embodiment, the polyalkoxyalkanoate is poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). Preferably, the molar ratio m:n in the aforementioned structural formula is 95:5 to 85:15, more preferably 90:10 to 88:12. Preferably, the molar ratio of 3-hydroxyhexanoate used is 5-15 mol%, preferably 7-13 mol%, more preferably 10-13 mol% of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), each based on a total monomer content of 100 mol% in poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) is sold, for example, by P&G or Kaneka. Polyhydroxyalkanoates, especially poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), can be obtained from renewable or fossil resources. Preferably, polyhydroxyalkanoates from renewable resources are used. More preferably, bio-based poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) can be used, which, for example, can be purchased from Kaneka under the trade name AONILEX151A. Preferably, the polyhydroxyalkanoate is biodegradable. In particular, poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) is a biodegradable polyhydroxyalkanoate.

[0130] Preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the filament suitable for 3D printing contains 1 to 25% by weight of polyhydroxyalkanoate. More preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the filament contains 2 to 22% by weight of polyhydroxyalkanoate. Still more preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the filament contains 3 to 20% by weight of polyhydroxyalkanoate. Even more preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the filament contains 3 to 18% by weight of polyhydroxyalkanoate. Even more preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the filament contains 5 to 15% by weight of polyhydroxyalkanoate. In particular, these ranges can be applied when the polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). Preferably, when the polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), the total amount of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) based on aliphatic polyester, aliphatic-aromatic polyester and polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) is 100% by weight, and the filament contains 20% by weight or less, more preferably 18% by weight or less of polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). If the proportion of poly(hydroxybutyrate-co-hydroxyhexanoate), preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), exceeds 18% by weight, it may become difficult to meet the biodegradability standard of EN13432 without pre-composting or industrial composting, and this becomes even more difficult when it exceeds 20% by weight. In a preferred embodiment, based on a total amount of 100% by weight of polybutylene succinate, butylene adipic acid terephthalate, and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), the filament comprises 12% by weight of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

[0131] In a highly preferred embodiment, the aliphatic polyester is polybutylene succinate (PBS), the aliphatic-aromatic polyester is polybutylene adipate terephthalate (PBAT), and the polyalkoxyalkylene ester is poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). Therefore, in a highly preferred embodiment, the filament suitable for 3D printing comprises polybutylene succinate (PBS), polybutylene adipate terephthalate (PBAT), and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

[0132] The ranges of amounts of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate can also be combined with each other. Thus, as an exemplary example, a filament suitable for 3D printing may contain 42 to 62% by weight, preferably 45 to 55% by weight, of aliphatic polyester; 26 to 46% by weight, preferably 30 to 40% by weight, of aliphatic-aromatic polyester; and 2 to 22% by weight, preferably 3 to 20% by weight, more preferably 3 to 18% by weight, of polyhydroxyalkanoate, each based on 100% by weight of the total amount of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate. Those skilled in the art will readily select suitable amounts of one or more polymers within the scope provided herein, such that the total amount of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate does not exceed 100% by weight. Specifically, these ranges can be applied when the aliphatic polyester is polybutylene succinate, the aliphatic aromatic polyester is polybutylene adipate terephthalate, and the polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). In a very preferred embodiment, the filament comprises 52% by weight of polybutylene succinate, 36% by weight of polybutylene adipate terephthalate, and 12% by weight of polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), each based on a total amount of 100% by weight of polybutylene succinate, polybutylene adipate terephthalate, and polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

[0133] In some embodiments, polyhydroxyalkanoates may be partially or completely replaced by polylactide (PLA, or also polylactic acid or poly(lactic acid)). Therefore, in some embodiments, when polyhydroxyalkanoates are partially replaced by polylactide, the filaments suitable for 3D printing comprise aliphatic polyesters, aliphatic-aromatic polyesters, polyhydroxyalkanoates, and polylactide. In some embodiments, when polyhydroxyalkanoates are completely replaced by polylactide, the filaments comprise aliphatic polyesters, aliphatic-aromatic polyesters, and polylactide. However, in embodiments where polyhydroxyalkanoates are completely replaced by polylactide, the filaments do not contain polyhydroxyalkanoates.

[0134] Optionally, the filament suitable for 3D printing may also contain at least one additive (or one or more additives). For example, the filament may contain at least one additive (or one or more additives) commonly known for use in 3D printing filaments. Optional additives may include, but are not limited to, additives such as flame retardants, matting agents, markers for identification (e.g., fluorescent markers), antimicrobial agents, colorants, plasticizers, fillers, and any combination thereof.

[0135] Preferably, the filaments suitable for 3D printing also include flame retardants, such as phosphates. As used herein, the term "phosphate" refers to filaments containing elements selected from [H₂PO₄]. – [HPO4] 2– and [PO4] 3– A salt of an anion. Preferably, the cation is ammonium [NH4]. + Therefore, in a preferred embodiment, the flame retardant is selected from ammonium dihydrogen phosphate ([NH4][H2PO4]), diammonium hydrogen phosphate ([NH4]2[HPO4]), triammonium phosphate ([NH4]3[PO4]), and any combination thereof. More preferably, the flame retardant is selected from ammonium dihydrogen phosphate ([NH4][H2PO4]), diammonium hydrogen phosphate ([NH4]2[HPO4]), and any combination thereof. More preferably, the flame retardant is ammonium dihydrogen phosphate ([NH4][H2PO4]) or diammonium hydrogen phosphate ([NH4]2[HPO4]). More preferably, the flame retardant is diammonium hydrogen phosphate ([NH4]2[HPO4]). Alternatively, or additionally, the flame retardant may be a polyphosphate. A "polyphosphate" is a salt or ester of a polymeric oxyanion formed by tetrahedral PO4 (phosphate) structural units linked together by shared oxygen atoms. Preferably, when the flame retardant is a polyphosphate, the flame retardant is ammonium polyphosphate.

[0136] Based on a total filament weight of 100% by weight, filaments suitable for 3D printing may contain 0.01 to 5% by weight of flame retardant. Preferably, based on a total filament weight of 100% by weight, the filament contains 0.1 to 4% by weight of flame retardant. More preferably, based on a total filament weight of 100% by weight, the filament contains 0.2 to 3% by weight of flame retardant. Still more preferably, based on a total filament weight of 100% by weight, the filament contains 0.3 to 3% by weight of flame retardant. Even more preferably, based on a total filament weight of 100% by weight, the filament contains 0.3 to 2% by weight of flame retardant. In particular, when the flame retardant is a phosphate or polyphosphate, preferably when the flame retardant is diammonium hydrogen phosphate ([NH4]2[HPO4]), the above range can be applied.

[0137] Optionally, the filaments suitable for 3D printing may (also) contain a matting agent. Any matting agent known to those skilled in the art can be used, such as typical matting agents used in filaments suitable for 3D printing. As an illustrative example, the matting agent may be zinc sulfide.

[0138] Optionally, the filament used for 3D printing may also include a marker suitable for identification. As an illustrative, non-limiting example, the marker suitable for identification could be a fluorescent marker. The fluorescence of the filament and the 3D printed article made from the filament can then be detected and identified using a suitable device. For example, a fluorescent marker available from Polysecure in Freiburg, Germany, can be used. The marker suitable for identification is typically used only in small amounts and generally does not alter the properties of the filament. Typically, the amount of the marker suitable for identification in the filament is in the range of ppb (parts per billion).

[0139] Optionally, the filament suitable for 3D printing may (also) contain an antimicrobial agent. Any antimicrobial agent known to those skilled in the art as suitable for 3D printing can be used. As an illustrative, non-limiting example, the antimicrobial agent may be zinc encapsulated in polyethylene terephthalate. Such an antimicrobial agent, for example, may be commercially available from SmartPolymer GmbH of Rudolstadt, Germany, under the trade name SMARTZINC 213 PET hot melt.

[0140] Optionally, the filament for 3D printing may (also) contain a plasticizer. Any plasticizer known to those skilled in the art and suitable for 3D printing filaments can be used. As an illustrative example, the plasticizer may be polycaprolactone. In particular, polycaprolactone is biodegradable. In some embodiments, based on 100% by weight of the total weight of the filament, the filament may contain 1% by weight or less of polycaprolactone. It has been found that filaments containing 1% by weight or less of polycaprolactone exhibit satisfactory softness and flexibility. However, it should be noted that filaments suitable for 3D printing according to the invention, comprising aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates, generally exhibit satisfactory softness and flexibility without the addition of polycaprolactone or other plasticizers.

[0141] Optionally, the filament may (also) contain a colorant. Any colorant suitable for 3D printing and providing the desired color can be used. As an illustrative example, the colorant may be an inorganic or organic pigment. Optionally, the printing filament may (also) contain a filler. Any filler known to those skilled in the art and suitable for 3D printing filaments can be used, preferably a biodegradable filler. As an illustrative example, the (biodegradable) filler may be lignin or may include lignin. Preferably, the lignin is oxygen-bleached lignin. Oxygen bleaching of lignin is an environmentally friendly method compared to conventional chlorine bleaching.

[0142] Those skilled in the art will readily select the appropriate amount of additive to be included in the filament. As an illustrative example, a filament suitable for 3D printing may contain 15% by weight or less of the total additive based on 100% by weight of the total filament weight. A filament may contain 10% by weight or less of the total additive based on 100% by weight of the total filament weight. Preferably, the filament contains 7% by weight or less of the total additive based on 100% by weight of the total filament weight. More preferably, the filament contains 5% by weight or less of the total additive based on 100% by weight of the total filament weight. Even more preferably, the filament contains 4% by weight or less of the total additive based on 100% by weight of the total filament weight. Even more preferably, the filament contains 3 to 4% by weight of the total additive based on 100% by weight of the total filament weight. Preferably, the filament contains 7% by weight or less, more preferably 3 to 4% by weight of the total additive based on 100% by weight of the total filament weight, to achieve filament stiffness useful for 3D printing.

[0143] The filament can have any diameter suitable for use in a 3D printer. Therefore, the diameter of a filament suitable for 3D printing can be 1.0 mm or greater. Preferably, the diameter of the filament can be 1.5 mm or greater. More preferably, the diameter of the filament can be 1.6 mm or greater. Even more preferably, the diameter of the filament can be 1.7 mm or greater. Alternatively, the diameter of a filament suitable for 3D printing can be 5.0 mm or less. Preferably, the diameter of the filament can be 4.0 mm or less. More preferably, the diameter of the filament can be 3.5 mm or less. Even more preferably, the diameter of the filament can be 3.0 mm or less. In some embodiments, the diameter of the filament suitable for 3D printing can be in the range of 1.70 mm to 1.80 mm. In some embodiments, the diameter of the filament suitable for 3D printing can be in the range of 2.80 mm to 3.05 mm.

[0144] Preferably, the filament suitable for 3D printing is biodegradable. More preferably, the filament is biodegradable according to EN 13432. Therefore, a filament can be considered biodegradable according to EN 13432 when, after a specified period of time, it has a biodegradation percentage equal to at least 90% of the DIN EN 13432 percentage. A general effect of biodegradability is that the filament decomposes within an appropriate and verifiable time interval. Degradation can be achieved by enzymatic, hydrolytic, oxidative, and / or electromagnetic radiation such as UV radiation, and can be primarily due to the action of microorganisms such as bacteria, yeast, fungi, and algae. For example, biodegradability can be quantified by mixing the filament with compost and storing it for a certain period of time. For example, during composting, CO2-free air can flow through the maturing compost, and the maturing compost undergoes a defined temperature program. Biodegradability can be defined, for example, as the percentage degree of biodegradation by the ratio of the net CO2 released by the sample (after deducting the CO2 released from compost without the sample) to the maximum amount of CO2 that the sample can release (calculated from the carbon content of the sample). Biodegradable filaments typically show obvious signs of degradation, such as fungal growth, cracking, and pore formation, just a few days after composting. Other methods for determining biodegradability are described, for example, in ASTM D 5338 and ASTM D 6400. Preferably, the 3D printed articles obtained by or derived therefrom using filaments suitable for 3D printing according to the invention are biodegradable. More preferably, the 3D printed articles are biodegradable according to EN 13432.

[0145] In some implementations, the filaments suitable for 3D printing are not hollow fibers or hollow filaments. The term "hollow fiber," as used herein and known in the art, generally refers to any fiber having one or more cavities in its cross-section. As used herein, the term "cavity" generally refers to a hollow space present within the cross-section of the fiber. The cavity may be filled with a gas, such as air. As an exemplary example, the cross-section of a hollow fiber may have a single continuous cavity. However, a hollow fiber may also include more than one cavity (e.g., 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, or even more cavities). In addition to one or more cavities, a hollow fiber may also include one or more portions having a dense structure. As used herein, the term "dense structure" may also be referred to as "compact structure," generally indicating that the fibrous material exists in a substantially dense or compact form, particularly when compared to the cavities of a hollow fiber. The terms "dense structure" or "compact structure" may also include structures containing pores, however, these pores are typically significantly smaller than the cavities of the hollow fiber. Hollow fibers that include both cavities and dense (or compact) structures may also be referred to as segmented fibers or segmented hollow fibers. As an exemplary example, a hollow fiber may include cavities and compact structures arranged in an alternating pattern along the longitudinal direction of the fiber. All the above definitions of "hollow fiber" also apply to "hollow filament".

[0146] Specifically, in some embodiments, the filaments suitable for 3D printing are not the fibers described in International Patent Application PCT / EP2022 / 075084. The fibers described in PCT / EP2022 / 075084 are also described below. Therefore, in some embodiments, the filaments suitable for 3D printing are not:

[0147] Fibers obtained by a method including the following steps or by a method including the following steps:

[0148] - A melt containing aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate is spun through a hollow fiber spinning nozzle to obtain precursor fibers; and

[0149] - The precursor fiber is obtained by cooling it under a temperature gradient.

[0150] The fibers obtained or acquired by this method comprise two parts, one thicker and the other thinner, and have the structure described below. Therefore, in some embodiments, the filaments suitable for 3D printing are not:

[0151] Fibers made from a mixture of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates.

[0152] The fiber comprises two parts in the longitudinal direction, one part being a thicker part and the other part being a thinner part, wherein the thicker part and the thinner part extend in a direction perpendicular to the longitudinal direction of the fiber, and wherein the extension of the thicker part in the vertical direction is greater than the extension of the thinner part in the vertical direction.

[0153] In this configuration, at least a portion of the thicker portion has a cavity, and at least a portion of the thinner portion has a compact structure. In some embodiments, the filament suitable for 3D printing is not:

[0154] Hollow fibers made from a mixture comprising aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates. In some embodiments, the filaments suitable for 3D printing are not segmented fibers or segmented hollow fibers.

[0155] In some embodiments, the filaments suitable for 3D printing are solid filaments. In some embodiments, the filaments suitable for 3D printing are non-hollow filaments. As used herein and known in the art, the term "solid filament" or also referred to as "non-hollow filament" generally refers to any filament in which the material of the filament exists in a substantially dense or compact form and does not have cavities, as described herein with respect to hollow filaments or hollow fibers. However, the terms "solid filament" or "non-hollow filament" do not preclude the filament from containing a few pores; however, these pores are generally significantly smaller than the cavities of hollow filaments or hollow fibers.

[0156] It is desirable to stably store and supply filaments for 3D printing to a 3D printer. Therefore, from the viewpoints of long-term preservation, stable filament drawing, protection from environmental factors including ultraviolet radiation, and prevention of twisting, it is preferable to package the filaments of the present invention as a roller obtained by winding the filaments onto a spool, or to house the roller in a housing. Therefore, the present invention also relates to a roller comprising filaments suitable for 3D printing according to the present invention. The present invention also relates to a housing suitable for a 3D printer, comprising filaments suitable for 3D printing according to the present invention. Examples of housings include: not only housing a roller for winding the filaments onto a spool, but also using a vapor-proof material or desiccant internally, and sealing at least the portion other than the opening for filament extraction. Typically, a roller obtained by winding filaments for 3D printing onto a spool, or a housing comprising a roller, is mounted in or around the 3D printer, and the filaments are continuously introduced from the housing into the 3D printer during the 3D printing process.

[0157] This invention also relates to a three-dimensional printed article, which can be obtained by subjecting or through a 3D printing process using a filament suitable for 3D printing according to the invention. The invention also relates to three-dimensional printed articles comprising aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates. Three-dimensional printed articles can be obtained by forming them using a 3D printer with a filament suitable for 3D printing. Generally, conventional 3D printers known in the art can be used. Examples of forming methods used with a 3D printer include material extrusion (ME), powder sintering, inkjet printing, photopolymerization (SLA), etc. Preferably, the filament of the invention is used in material extrusion. The three-dimensional printed article is not particularly limited. Generally, any article having the desired shape can be prepared from the filament in a 3D printing process. Illustrative examples of three-dimensional printed articles obtainable from or obtained from the filament according to the invention may include products for fixing; toys; casings for mobile phones, smartphones, etc.; parts, such as handles; school textbooks; household appliances; parts for automobiles, motorcycles, bicycles, etc.; electrical / electronic equipment; agricultural materials; horticultural materials; fishery materials; materials for civil engineering / construction; and medical supplies. In some implementations, the 3D printed article can be a plastic card, such as a plastic card in the form of a credit card.

[0158] The present invention also relates to a method for preparing filaments suitable for 3D printing according to the invention, the method comprising extruding a melt comprising an aliphatic polyester, an aliphatic-aromatic polyester, and a polyhydroxyalkanoate into filament form to obtain the filament. As described herein, the filament may be further defined as any filament suitable for 3D printing. The melt used to prepare the filament may be prepared using any method known to those skilled in the art for preparing a melt. As an illustrative example, the aliphatic polyester, the aliphatic-aromatic polyester, and the polyhydroxyalkanoate may be mixed in a non-molten state, for example by mixing polymer particles, optionally with one or more other additives. Optionally, the polymer and, if present, the additives may be dried prior to mixing and preparing the melt. The mixture may then be heated to the melting point of the polymer or above in order to prepare the melt. As an illustrative example, mixing and heating may be carried out in an extruder. In some embodiments, particularly prior to extrusion, the melt may have a temperature of 200°C to 260°C, preferably 220°C to 250°C, more preferably 230°C to 250°C, and even more preferably 230°C to 240°C. As an illustrative example, the melt can be heated to a temperature of 235°C and then extruded into a filament shape. To obtain the filament, the melt can be extruded through a nozzle or any other orifice with a suitable shape, particularly a circular shape. Optionally, the filament can be cooled after extrusion, for example by air cooling or water cooling. Suitable cooling devices / equipment for cooling are generally known and readily selected by those skilled in the art. Preferably, based on a total amount of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the melt contains 30 to 70% by weight of aliphatic polyester. More preferably, based on a total amount of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the melt contains 35 to 65% by weight of aliphatic polyester. Even more preferably, based on a total amount of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the melt contains 40 to 60% by weight or 42 to 62% by weight of aliphatic polyester. Even more preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the melt contains 45 to 55% by weight of aliphatic polyester. In particular, these ranges can be applied when the aliphatic polyester is polybutylene succinate. In a preferred embodiment, based on a total of 100% by weight of polybutylene succinate, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the melt contains 52% by weight of polybutylene succinate.

[0159] Preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the melt contains 10 to 60% by weight of aliphatic-aromatic polyester. More preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the melt contains 20 to 50% by weight of aliphatic-aromatic polyester. Even more preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the melt contains 25 to 40% by weight or 26 to 46% by weight of aliphatic-aromatic polyester. Even more preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the melt contains 30 to 40% by weight of aliphatic-aromatic polyester. In particular, these ranges can be applied when the aliphatic-aromatic polyester is polybutylene terephthalate (PBAT). In a preferred embodiment, the melt contains 36% by weight of polybutylene terephthalate (PBAT) based on a total amount of 100% by weight of aliphatic polyester, polybutylene terephthalate (PBAT) and polyhydroxyalkanoate.

[0160] Preferably, based on a 100% by weight total amount of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the melt contains 1 to 25% by weight of polyhydroxyalkanoate. More preferably, based on a 100% by weight total amount of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the melt contains 2 to 22% by weight of polyhydroxyalkanoate. Even more preferably, based on a 100% by weight total amount of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the melt contains 3 to 20% by weight of polyhydroxyalkanoate. Even more preferably, based on a 100% by weight total amount of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the melt contains 3 to 18% by weight of polyhydroxyalkanoate. Even more preferably, based on a 100% by weight total amount of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the melt contains 5 to 15% by weight of polyhydroxyalkanoate. In particular, these ranges can be applied when the polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). Preferably, when the polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), the total amount of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) is 100% by weight, and the melt contains 20% by weight or less, more preferably 18% by weight or less of polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

[0161] The ranges of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates can also be combined with each other. Thus, as an illustrative example, the melt may contain 42 to 62% by weight, preferably 45 to 55% by weight, of aliphatic polyester; the melt may contain 26 to 46% by weight, preferably 30 to 40% by weight, of aliphatic-aromatic polyester; and the melt may contain 2 to 22% by weight, preferably 3 to 20% by weight, more preferably 3 to 18% by weight, of polyhydroxybutyrate, each based on a total amount of 100% by weight of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates. Those skilled in the art will readily select suitable amounts of one or more polymers within the range provided herein, such that the total amount of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates does not exceed 100% by weight. Specifically, these ranges can be applied when the aliphatic polyester is polybutylene succinate, the aliphatic aromatic polyester is polybutylene adipate terephthalate, and the polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). In a very preferred embodiment, the melt comprises 52% by weight of polybutylene succinate, 36% by weight of polybutylene adipate terephthalate, and 12% by weight of polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), each based on a total amount of 100% by weight of polybutylene succinate, polybutylene adipate terephthalate, and polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

[0162] In some embodiments, polyhydroxyalkanoates may be partially or completely replaced by polylactide (PLA, also known as polylactic acid or poly(lactic acid)). Therefore, in some embodiments, when polyhydroxyalkanoates are partially replaced by polylactide, the melt comprises aliphatic polyesters, aliphatic-aromatic polyesters, polyhydroxyalkanoates, and polylactide. In some embodiments, when polyhydroxyalkanoates are completely replaced by polylactide, the melt comprises aliphatic polyesters, aliphatic-aromatic polyesters, and polylactide. However, in embodiments where polyhydroxyalkanoates are completely replaced by polylactide, the melt does not contain polyhydroxyalkanoates.

[0163] Optionally, the melt may further comprise at least one additive. For example, the melt may comprise at least one additive commonly known for use in filaments suitable for 3D printing. Optional additives may include, but are not limited to, additives selected from flame retardants, matting agents, identification markers (e.g., fluorescent markers), antimicrobial agents, plasticizers, colorants, fillers, and any combination thereof.

[0164] Preferably, the melt further comprises a flame retardant. More preferably, the flame retardant is a phosphate. In a preferred embodiment, the flame retardant is selected from ammonium dihydrogen phosphate ([NH4][H2PO4]), diammonium hydrogen phosphate ([NH4]2[HPO4]), triammonium phosphate ([NH4]3[PO4]), and any combination thereof. More preferably, the flame retardant is selected from ammonium dihydrogen phosphate ([NH4][H2PO4]), diammonium hydrogen phosphate ([NH4]2[HPO4]), and any combination thereof. More preferably, the flame retardant is ammonium dihydrogen phosphate ([NH4][H2PO4]) or diammonium hydrogen phosphate ([NH4]2[HPO4]). More preferably, the flame retardant is diammonium hydrogen phosphate ([NH4]2[HPO4]). Alternatively, or additionally, the flame retardant may be a polyphosphate. Preferably, when the flame retardant is a polyphosphate, the flame retardant is ammonium polyphosphate.

[0165] Based on a total melt weight of 100% by weight, the melt may contain 0.01 to 5% by weight of flame retardant. Preferably, based on a total melt weight of 100% by weight, the melt contains 0.1 to 4% by weight of flame retardant. More preferably, based on a total melt weight of 100% by weight, the melt contains 0.2 to 3% by weight of flame retardant. Even more preferably, based on a total melt weight of 100% by weight, the melt contains 0.3 to 3% by weight of flame retardant. Even more preferably, based on a total melt weight of 100% by weight, the melt contains 0.3 to 2% by weight of flame retardant. In particular, when the flame retardant is a phosphate or polyphosphate, preferably when the flame retardant is diammonium hydrogen phosphate ([NH4]2[HPO4]), the above ranges can be applied.

[0166] Those skilled in the art will readily select the appropriate amount of additives contained in the melt. As an illustrative example, based on a total melt weight of 100% by weight, the melt may contain a total of 15% by weight or less of additives. Based on a total melt weight of 100% by weight, the total amount of additives in the melt may be 10% by weight or less. Preferably, based on a total melt weight of 100% by weight, the melt contains a total of 7% by weight or less of additives. More preferably, based on a total melt weight of 100% by weight, the melt contains a total of 5% by weight or less of additives. Even more preferably, based on a total melt weight of 100% by weight, the melt contains a total of 4% by weight or less of additives. Even more preferably, based on a total melt weight of 100% by weight, the melt contains a total of 3 to 4% by weight of additives. Preferably, the melt contains a total of 7% by weight or less, more preferably 3 to 4% by weight of additives, each based on a total melt weight of 100% by weight, to achieve filament stiffness suitable for 3D printing.

[0167] In some implementations, the melt is not extruded through a hollow fiber spinning nozzle to form filaments suitable for 3D printing. As used herein, the term "hollow fiber spinning nozzle" refers to any hollow fiber spinning nozzle commonly known in the art. Illustrative examples of hollow fiber spinning nozzles are described, for example, in EP 2112256, the entire contents of which are incorporated herein by reference.

[0168] In some embodiments, the method for preparing filaments suitable for 3D printing is not the fiber preparation method described in International Patent Application PCT / EP2022 / 075084. Specifically, in some embodiments, the method for preparing filaments suitable for 3D printing is not:

[0169] A method for preparing fibers, comprising:

[0170] - The melts of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates are spun through hollow fiber spinning nozzles to obtain precursor fibers; and

[0171] - The precursor fiber is obtained by cooling it under a temperature gradient.

[0172] The present invention also relates to a filament suitable for three-dimensional printing, which can be obtained by or through a method for preparing filaments for three-dimensional printing according to the present invention.

[0173] The present invention also relates to the use of melts comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates for the preparation of filaments suitable for three-dimensional printing, wherein the filaments are as defined herein.

[0174] The present invention also relates to the use of melts comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates for the preparation of filaments suitable for three-dimensional printing.

[0175] A mixture comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates

[0176] The present invention also relates to mixtures comprising aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates. Such mixtures can be used, for example, to prepare fibers or filaments suitable for three-dimensional printing according to the present invention.

[0177] The aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate contained in the mixture may be further defined as described herein, particularly for any fiber or filament suitable for 3D printing. In a highly preferred embodiment, the aliphatic polyester is polybutylene succinate (PBS), the aliphatic-aromatic polyester is polybutylene adipate terephthalate (PBAT), and the polyhydroxyalkanoate is poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). Therefore, the invention also relates to a mixture comprising polybutylene succinate (PBS), polybutylene adipate terephthalate (PBAT), and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). In some embodiments, the mixture consists essentially of an aliphatic polyester, an aliphatic-aromatic polyester, and a polyhydroxyalkanoate. In some embodiments, the mixture is substantially composed of polybutylene succinate (PBS), polybutylene adipate terephthalate (PBAT), and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). In some embodiments, the mixture is composed of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates. In some embodiments, the mixture is composed of polybutylene succinate (PBS), polybutylene adipate terephthalate (PBAT), and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

[0178] In the mixture, aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates may be present in particulate form. Illustrative examples of particles that can be used in the mixture may be selected from granules, pellets, extrudates, beads, spheres, and any combination thereof. Preferably, the aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates are in particulate form. In a very preferred embodiment, the mixture comprises polybutylene succinate (PBS), polybutylene adipate terephthalate (PBAT), and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) in particulate form. The invention also relates to particles comprising polybutylene succinate (PBS), polybutylene adipate terephthalate (PBAT), and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). To prepare fibers or filaments suitable for 3D printing, the mixture containing polymer particles may be heated above the melting point of the polymer. In some embodiments, the mixture may therefore be present in melt form. As described in this article, the melt can be spun into fibers or extruded into filaments suitable for 3D printing.

[0179] Preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the mixture comprises 30 to 70% by weight of aliphatic polyester. More preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the mixture comprises 35 to 65% by weight of aliphatic polyester. Even more preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the mixture comprises 40 to 60% by weight or 42 to 62% by weight of aliphatic polyester. Even more preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the mixture comprises 45 to 55% by weight of aliphatic polyester. In particular, these ranges can be applied when the aliphatic polyester is polybutylene succinate. In a preferred embodiment, based on a total amount of 100% by weight of polybutylene succinate, aliphatic aromatic polyester and polyhydroxyalkanoate, the mixture contains 52% by weight of polybutylene succinate.

[0180] Preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the mixture contains 10 to 60% by weight of aliphatic-aromatic polyester. More preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the mixture contains 20 to 50% by weight of aliphatic-aromatic polyester. Even more preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the mixture contains 25 to 40% by weight or 26 to 46% by weight of aliphatic-aromatic polyester. Even more preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the mixture contains 30 to 40% by weight of aliphatic-aromatic polyester. In particular, these ranges can be applied when the aliphatic-aromatic polyester is polybutylene terephthalate (PBAT). In a preferred embodiment, based on a total amount of aliphatic polyester, polybutylene terephthalate (PBAT), and polyhydroxyalkanoate of 100% by weight, the mixture contains 36% by weight of polybutylene terephthalate (PBAT).

[0181] Preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the mixture contains 1 to 25% by weight of polyhydroxyalkanoate. More preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the mixture contains 2 to 22% by weight of polyhydroxyalkanoate. Even more preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the mixture contains 3 to 20% by weight of polyhydroxyalkanoate. Even more preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the mixture contains 3 to 18% by weight of polyhydroxyalkanoate. Even more preferably, based on a total of 100% by weight of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the mixture contains 5 to 15% by weight of polyhydroxyalkanoate. In particular, these ranges can be applied when the polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). Preferably, when the polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), the total amount of aliphatic polyester, aliphatic-aromatic polyester and polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) is 100% by weight, and the mixture contains 20% by weight or less, more preferably 18% by weight or less of polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

[0182] The ranges of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates can also be combined with each other. Thus, as an illustrative example, based on a total amount of 100% by weight for each of the aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, the mixture may contain 42 to 62% by weight, preferably 45 to 55% by weight, of aliphatic polyester; the mixture may contain 26 to 46% by weight, preferably 30 to 40% by weight, of aliphatic-aromatic polyester; and the mixture may contain 2 to 22% by weight, preferably 3 to 20% by weight, more preferably 3 to 18% by weight, of polyhydroxybutyrate. Those skilled in the art will readily select suitable amounts of one or more polymers within the range provided herein, such that the total amount of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate does not exceed 100% by weight. Specifically, these ranges can be applied when the aliphatic polyester is polybutylene succinate, the aliphatic aromatic polyester is polybutylene adipate terephthalate, and the polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). In a very preferred embodiment, the total amount of each of polybutylene succinate, polybutylene adipate terephthalate, and polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH) is 100% by weight, and the mixture comprises 52% by weight of polybutylene succinate, 36% by weight of polybutylene adipate terephthalate, and 12% by weight of polyhydroxybutyrate-co-hydroxyhexanoate, preferably poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

[0183] Optionally, the mixture may further comprise at least one additive. For example, the mixture may comprise at least one additive commonly known for use in textile fibers or filaments suitable for 3D printing. Optional additives may include, but are not limited to, additives selected from flame retardants, matting agents, identification markers (e.g., fluorescent markers), antimicrobial agents, plasticizers, colorants, fillers, and any combination thereof.

[0184] Preferably, the mixture further comprises a flame retardant. More preferably, the flame retardant is a phosphate. In a preferred embodiment, the flame retardant is selected from ammonium dihydrogen phosphate ([NH4][H2PO4]), diammonium hydrogen phosphate ([NH4]2[HPO4]), triammonium phosphate ([NH4]3[PO4]), and any combination thereof. More preferably, the flame retardant is selected from ammonium dihydrogen phosphate ([NH4][H2PO4]), diammonium hydrogen phosphate ([NH4]2[HPO4]), and any combination thereof. More preferably, the flame retardant is ammonium dihydrogen phosphate ([NH4][H2PO4]) or diammonium hydrogen phosphate ([NH4]2[HPO4]). More preferably, the flame retardant is diammonium hydrogen phosphate ([NH4]2[HPO4]). Alternatively or additionally, the flame retardant may be a polyphosphate. Preferably, when the flame retardant is a polyphosphate, the flame retardant is ammonium polyphosphate.

[0185] Based on a total weight of 100 wt%, the mixture may contain 0.01 to 5 wt% of flame retardant. Preferably, based on a total weight of 100 wt%, the mixture contains 0.1 to 4 wt% of flame retardant. More preferably, based on a total weight of 100 wt%, the mixture contains 0.2 to 3 wt% of flame retardant. Even more preferably, based on a total weight of 100 wt%, the mixture contains 0.3 to 3 wt% of flame retardant. Even more preferably, based on a total weight of 100 wt%, the mixture contains 0.3 to 2 wt% of flame retardant. In particular, the above ranges can be applied when the flame retardant is a phosphate or polyphosphate, preferably when the flame retardant is diammonium hydrogen phosphate ([NH4]2[HPO4]).

[0186] Those skilled in the art will readily select the appropriate amount of additives to be included in the mixture. As an illustrative example, based on a total weight of 100% by weight, the mixture may contain 15% by weight or less of additives. Based on a total weight of 100% by weight, the mixture may contain 10% by weight or less of additives. Preferably, based on a total weight of 100% by weight, the mixture contains 7% by weight or less of additives. More preferably, based on a total weight of 100% by weight, the mixture contains 5% by weight or less of additives. Even more preferably, based on a total weight of 100% by weight, the mixture contains 4% by weight or less of additives. Even more preferably, based on a total weight of 100% by weight, the mixture contains 3 to 4% by weight of additives. Preferably, each additive contains 7% by weight or less, more preferably 3 to 4% by weight, based on a total weight of 100% by weight, in order to obtain stiffness suitable for use in textile fibers or filaments suitable for 3D printing.

[0187] The present invention also relates to the use of mixtures comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates in the preparation of fibers, wherein the fibers are as defined herein.

[0188] The present invention also relates to the use of mixtures comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates in the preparation of fibers.

[0189] The present invention also relates to the use of mixtures comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates for the preparation of filaments suitable for three-dimensional printing, wherein the filaments are as defined herein.

[0190] The present invention also relates to the use of mixtures comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates for the preparation of filaments suitable for three-dimensional printing.

[0191] It should be noted that, as used herein, the singular forms “an,” “a,” and “the” include plural references unless the context clearly indicates otherwise. Thus, for example, reference to “a reagent” includes one or more such different reagents, and reference to “the method” includes reference to equivalent steps and methods known to those skilled in the art, which may be modified or substituted for the methods described herein.

[0192] Unless otherwise stated, the term "at least" preceding a series of elements should be understood to refer to each element in the series. Those skilled in the art will recognize or be able to determine many equivalent embodiments of the invention described herein using no more than conventional experiments. These equivalents are also included in this invention.

[0193] Wherever the term “and / or” is used in this document, it includes the meaning of “and,” “or,” and “all or any other combination of the elements connected by the term.”

[0194] The terms “less than” or “greater than” do not include specific numbers. For example, “less than 20” means less than the indicated number. Similarly, “greater than” means greater than the indicated number; for example, “greater than 80%” means greater than 80% of the indicated number.

[0195] Throughout this specification and the following claims, unless the context otherwise requires, the word “comprising” and its variations such as “including” and “containing” shall be construed as implying the inclusion of the stated whole or step or group of whole or steps, but not excluding any other whole or step or group of whole or steps. When used herein, the term “comprising” may be replaced by the terms “containing” or “including”, or sometimes by the term “having” when used herein.

[0196] When used herein, “composed of” excludes any element, step or component not specified in the elements of the claim, and when used herein, “consistently composed of” does not exclude material or steps that do not substantially affect the essential and novel features of the claim. In each case herein, any one of the terms “comprising,” “consistently composed of,” and “composed of” may be replaced by any of the other two terms.

[0197] The term "including" means "including but not limited to". "Including" and "including but not limited to" are used interchangeably.

[0198] When used herein, the term “about” should be understood to mean that a variation may exist within the corresponding value or range (such as pH, concentration, percentage, molar concentration, time, etc.), which may be up to 5% or up to 10% of a given value. For example, if a formulation contains about 5 mg / ml of a compound, this is understood to mean that the formulation may have a concentration of 4.5 to 5.5 mg / ml.

[0199] It should be understood that the present invention is not limited to the specific methods, schemes, materials, reagents, and substances described herein, and therefore variations are possible. The terminology used herein is for the purpose of describing specific embodiments only and is not intended to limit the scope of the invention, which is defined only by the claims.

[0200] All publications (including all patents, patent applications, scientific publications, specifications, etc.) cited throughout this specification are incorporated herein by reference in their entirety, whether above or below. Nothing herein is to be construed as an admission that the invention is not entitled to any prior art based on such disclosures. To the extent that any material incorporated by reference contradicts or is inconsistent with this specification, this specification supersedes any such material.

[0201] All references and patent documents cited herein are incorporated herein by reference in their entirety.

[0202] The invention is further characterized by the following items:

[0203] 1. A fiber made from a mixture comprising aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate.

[0204] 2. The fiber according to Item 1, wherein the aliphatic polyester comprises aliphatic C2-C... 20 Dicarboxylic acids and aliphatic C2-C 12 Diol.

[0205] 3. The fiber according to item 1 or 2, wherein the aliphatic polyester is selected from polybutylene succinate (PBS), polyethylene oxalate, polyethylene malonate, polyethylene succinate, polypropylene oxalate, polypropylene malonate, polypropylene succinate, polybutylene oxalate, polybutylene malonate, polybutylene succinate-co-butylene adipate (PBSA), polybutylene succinate-co-butylene azelaate (PBSAz), polybutylene succinate-co-butylene brassinate (PBSBr), and any combination thereof.

[0206] 4. The fiber according to any one of the preceding items, wherein the aliphatic polyester is selected from polybutylene succinate (PBS), polybutylene-adipate succinate (PBSA), polybutylene-azelate succinate (PBSAz), polybutylene-brasinate succinate (PBSBr), and any combination thereof.

[0207] 5. The fiber according to any one of the preceding items, wherein the aliphatic polyester is polybutylene succinate (PBS).

[0208] 6. The fiber according to any one of the preceding items, wherein, based on a total amount of 100% by weight of the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate, the fiber comprises 30% to 70% by weight of the aliphatic polyester.

[0209] 7. The fiber according to any one of the foregoing items, wherein the aliphatic-aromatic polyester comprises C2-C 12 Aliphatic dicarboxylic acids, aromatic dicarboxylic acids and aliphatic C2-C 12 Diol.

[0210] 8. The fiber according to any one of the preceding items, wherein the aliphatic-aromatic polyester is selected from polybutylene adipate terephthalate (PBAT), polybutylene terephthalate succinate (PBST), polybutylene sebacate terephthalate (PBSeT), and any combination thereof.

[0211] 9. The fiber according to any one of the preceding items, wherein the aliphatic-aromatic polyester is polybutylene adipate terephthalate (PBAT).

[0212] 10. The fiber according to any one of the preceding items, wherein the fiber contains 10% to 60% by weight of the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate, based on a total weight of 100% by weight.

[0213] 11. The fiber according to any one of the preceding items, wherein the polyhydroxyalkanoate comprises C3-C18 Hydroxyalkylcarboxylic acids.

[0214] 12. The fiber according to any one of the preceding items, wherein the polyhydroxyalkanoate is selected from polyhydroxybutyrate-co-hydroxyhexanoate, polyhydroxybutyrate, polyhydroxyvalerate, polyhydroxybutyrate-co-hydroxyvalerate, and any combination thereof.

[0215] 13. The fiber according to any one of the preceding items, wherein the polyhydroxyalkanoate is selected from poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), poly-3-hydroxybutyrate (P3HB), poly-4-hydroxybutyrate (P4HB), poly-3-hydroxyvalerate (PHV), poly(3-hydroxybutyrate-co-4-hydroxybutyrate), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), and any combination thereof.

[0216] 14. The fiber according to any one of the preceding items, wherein the polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate.

[0217] 15. The fiber according to any one of the preceding items, wherein the polyhydroxyalkanoate is poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

[0218] 16. The fiber according to any one of the preceding items, wherein, based on a total amount of the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate of 100% by weight, the fiber contains 1 to 25% by weight of the polyhydroxyalkanoate.

[0219] 17. The fiber according to any one of the preceding items, wherein, based on a total amount of 100% by weight of the aliphatic polyester, the aromatic-aliphatic polyester and the polyhydroxyalkanoate, the fiber comprises 42% to 62% by weight of the aliphatic polyester, 26% to 46% by weight of the aromatic-aliphatic polyester and 2% to 22% by weight of the polyhydroxyalkanoate.

[0220] 18. The fiber according to any one of the preceding items, wherein the aliphatic polyester is polybutylene succinate (PBS), the aliphatic-aromatic polyester is polybutylene adipate terephthalate (PBAT), and the polyhydroxyalkanoate is poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

[0221] 19. The fiber according to any one of the preceding items, wherein the polyhydroxyalkanoate is partially or completely replaced by polylactide.

[0222] 20. The fiber according to any one of the preceding items, wherein the fiber is a textile fiber.

[0223] 21. The fiber according to any one of the preceding items, wherein the fiber further comprises at least one additive.

[0224] 22. The fiber according to item 21, wherein the at least one additive is selected from flame retardants, matting agents, fluorescent markers, antimicrobial agents, plasticizers, fillers, and any combination thereof.

[0225] 23. The fiber according to item 22, wherein the additive is a flame retardant.

[0226] 24. The fiber according to item 23, wherein the flame retardant is a phosphate selected from ammonium dihydrogen phosphate ([NH4][H2PO4]), diammonium hydrogen phosphate ([NH4]2[HPO4]), triammonium phosphate ([NH4]3[PO4]), ammonium polyphosphate, and any combination thereof.

[0227] 25. The fiber according to item 24, wherein the phosphate is diammonium hydrogen phosphate ([NH4]2[HPO4]).

[0228] 26. The fiber according to any one of items 22 to 25, wherein, based on a total fiber weight of 100% by weight, the fiber contains 0.01 to 5% by weight, preferably 0.1 to 4% by weight, more preferably 0.2 to 3% by weight, and even more preferably 0.3 to 2% by weight of a flame retardant.

[0229] 27. The fiber according to item 22, wherein the additive is a matting agent.

[0230] 28. The fiber according to item 27, wherein the matting agent is zinc sulfide.

[0231] 29. The fiber according to item 22, wherein the additive is a fluorescent marker.

[0232] 30. The fiber according to item 22, wherein the additive is an antimicrobial agent.

[0233] 31. The fiber according to item 30, wherein the antimicrobial agent is zinc encapsulated in polyethylene terephthalate.

[0234] 32. The fiber according to item 31, wherein the additive is a filler.

[0235] 33. The fiber according to item 32, wherein the filler is lignin or contains lignin.

[0236] 34. The fiber according to any one of items 21 to 33, wherein, based on a total fiber weight of 100% by weight, the fiber contains a total of 15% by weight or less, preferably 10% by weight or less, more preferably 7% by weight or less, even more preferably 5% by weight or less, even more preferably 4% by weight or less, even more preferably 3 to 4% by weight.

[0237] 35. The fiber according to any one of the preceding items, wherein the fiber has a fineness of 0.5 to 8 denier, preferably 0.8 to 6 denier, more preferably 0.9 to 3 denier, even more preferably 1.0 to 2 denier, even more preferably 1.0 to 1.5 denier, even more preferably 1.1 to 1.2 denier.

[0238] 36. The fiber according to any one of the preceding items, wherein the fiber is a short fiber.

[0239] 37. The fiber according to item 36, wherein the fiber has a short fiber length of 2 to 80 mm, preferably 5 to 70 mm, more preferably 10 to 60 mm, even more preferably 15 to 50 mm, even more preferably 20 to 40 mm, even more preferably 22 to 35 mm, even more preferably 25 to 32 mm.

[0240] 38. The fiber according to any one of items 1 to 35, wherein the fiber is a filament.

[0241] 39. The fiber according to any one of the preceding items, wherein the fiber is biodegradable according to EN 13432.

[0242] 40. The fiber according to any one of the preceding items, wherein said fiber is not:

[0243] Fibers obtained by a method including the following steps or by a method including the following steps:

[0244] - The melts of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates are spun through hollow fiber spinning nozzles to obtain precursor fibers; and

[0245] - The precursor fiber is obtained by cooling it under a temperature gradient.

[0246] 41. The fiber according to any one of the preceding items, wherein said fiber is not:

[0247] Fibers made from a mixture of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates.

[0248] The fiber comprises two parts in the longitudinal direction, one part being a thicker part and the other part being a thinner part, wherein the thicker part and the thinner part extend in a direction perpendicular to the longitudinal direction of the fiber, and wherein the extension of the thicker part in the vertical direction is greater than the extension of the thinner part in the vertical direction.

[0249] At least a portion of the thicker portion has a cavity, and at least a portion of the thinner portion has a dense structure.

[0250] 42. The fiber according to any one of the preceding items, wherein said fiber is not:

[0251] A hollow fiber made from a mixture comprising aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate.

[0252] 43. The fiber according to any one of the preceding items, wherein the fiber is not a segmented fiber or a segmented hollow fiber.

[0253] 44. A yarn comprising fibers according to any one of items 1 to 43.

[0254] 45. A textile comprising fibers according to any one of items 1 to 43 or yarns according to item 44.

[0255] 46. ​​The textiles according to item 45, wherein the textiles are clothing or home textiles.

[0256] 47. The textiles according to item 46, wherein the garment is selected from shirts, polo shirts, trousers, jackets, underwear, socks, coats, shoes and shoelaces.

[0257] 48. The textiles according to item 47, wherein the home textiles are selected from curtains, carpets, blankets, sheets, duvet covers, mattress covers and towels.

[0258] 49. A method for preparing fibers according to any one of items 1 to 43, comprising:

[0259] - By spinning melts of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates through a spinning nozzle, precursor fibers are obtained; and

[0260] - Cool the precursor fibers to obtain the fibers.

[0261] 49a. The method according to item 49, wherein the temperature of the melt is in the range of 200°C to 260°C, preferably in the range of 220°C to 250°C, more preferably in the range of 230°C to 250°C, and even more preferably in the range of 230°C to 240°C.

[0262] 50. The method according to item 49, wherein the cooling is achieved by air cooling.

[0263] 51. The method according to item 49 or 50, wherein the melt contains 30% to 70% by weight of aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate, based on a total amount of 100% by weight.

[0264] 52. The method according to any one of items 49 to 51, wherein the total amount of aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate is 100% by weight, and the melt contains 10% to 60% by weight of the aliphatic-aromatic compound.

[0265] 53. The method according to any one of items 49 to 52, wherein the melt contains 1 to 25% by weight of polyhydroxyalkanoate based on aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate totaling 100% by weight.

[0266] 54. The method according to any one of items 49 to 53, wherein the melt comprises 42 to 62% by weight of aliphatic polyester, 26 to 46% by weight of aromatic-aliphatic polyester and 2 to 22% by weight of polyhydroxyalkanoate, based on a total amount of 100% by weight of aliphatic polyester, aromatic-aliphatic polyester and polyhydroxyalkanoate.

[0267] 55. The method according to any one of items 49 to 54, wherein the polyhydroxyalkanoate is partially or completely replaced by polylactide.

[0268] 56. The method according to any one of items 49 to 55, wherein the melt further comprises at least one additive.

[0269] 57. The method according to item 56, wherein the at least one additive is selected from flame retardants, matting agents, fluorescent markers, antimicrobial agents, plasticizers, fillers, and any combination thereof.

[0270] 58. The method according to item 57, wherein the additive is a flame retardant.

[0271] 59. The method according to item 58, wherein, based on the total weight of the melt being 100% by weight, the melt contains 0.01 to 5% by weight, preferably 0.1 to 4% by weight, more preferably 0.2 to 3% by weight, and even more preferably 0.3 to 2% by weight of a flame retardant.

[0272] 60. The method according to any one of items 56 to 59, wherein the total amount of the additive is 15% by weight or less, preferably 10% by weight or less, more preferably 7% by weight or less, even more preferably 5% by weight or less, even more preferably 4% by weight or less, even more preferably 3 to 4% by weight, based on a total melt weight of 100% by weight.

[0273] 61. The method according to any one of items 49 to 60, wherein the fiber is prepared as a short fiber.

[0274] 62. The method according to any one of items 49 to 60, wherein the fiber is prepared into a filament.

[0275] 63. The method according to any one of items 49 to 62, wherein the spinning nozzle is not a hollow fiber spinning nozzle.

[0276] 64. The method according to any one of items 49 to 63, wherein the method is not:

[0277] A method for preparing fibers, comprising:

[0278] - The melts of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates are spun through hollow fiber spinning nozzles to obtain precursor fibers; and

[0279] - The precursor fiber is obtained by cooling it under a temperature gradient.

[0280] 65. A fiber which can be obtained by or through any one of items 49 to 64.

[0281] 66. Use of a melt comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates for the preparation of fibers, wherein the fibers are as defined in any one of items 1 to 43.

[0282] 67. Use of melts comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates for the preparation of fibers.

[0283] 68. Use of mixtures comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates in the preparation of fibers, wherein the fibers are as defined in any one of items 1 to 43.

[0284] 69. Use of mixtures comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates in the preparation of fibers.

[0285] 70. A filament suitable for 3D printing, said filament being made of a mixture comprising an aliphatic polyester, an aliphatic-aromatic polyester, and a polyhydroxyalkanoate.

[0286] 71. The filament according to item 70, wherein the aliphatic polyester comprises aliphatic C2-C 20 Dicarboxylic acids and aliphatic C2-C 12 Diol.

[0287] 72. The filament according to item 70 or 71, wherein the aliphatic polyester is selected from polybutylene succinate (PBS), polyethylene oxalate, polyethylene malonate, polyethylene succinate, polypropylene oxalate, polypropylene malonate, polypropylene oxalate, polybutylene oxalate, polybutylene malonate, polybutylene malonate, polybutylene-co-adipate (PBSA), polybutylene-co-azelate (PBSAz), polybutylene-co-brasinate (PBSBr), and any combination thereof.

[0288] 73. The filament according to any one of items 70 to 72, wherein the aliphatic polyester is selected from polybutylene succinate (PBS), polybutylene-adipate-polysuccinate (PBSA), polybutylene-azelate-polysuccinate (PBSAz), polybutylene-brasuccinate-polysuccinate (PBSBr), and any combination thereof.

[0289] 74. The filament according to any one of items 70 to 73, wherein the aliphatic polyester is polybutylene succinate (PBS).

[0290] 75. The filament according to any one of items 70 to 74, wherein the filament comprises 30% to 70% by weight of the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate, based on a total amount of 100%.

[0291] 76. The filament according to any one of items 70 to 75, wherein the aliphatic-aromatic polyester comprises C2-C 12 Aliphatic dicarboxylic acids, aromatic dicarboxylic acids and aliphatic C2-C 12 Diol.

[0292] 77. The filament according to any one of items 70 to 76, wherein the aliphatic-aromatic polyester is selected from polybutylene adipate terephthalate (PBAT), polybutylene terephthalate succinate (PBST), polybutylene sebacate terephthalate (PBSeT), and any combination thereof.

[0293] 78. The filament according to any one of items 70 to 77, wherein the aliphatic-aromatic polyester is polybutylene adipate terephthalate (PBAT).

[0294] 79. The filament according to any one of items 70 to 78, wherein the total amount of aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate is 100% by weight, and the filament contains 10% to 60% by weight of the aliphatic-aromatic compound.

[0295] 80. The filament according to any one of items 70 to 79, wherein the polyhydroxyalkanoate comprises C3-C 18 Hydroxyalkyl carboxylic acid.

[0296] 81. The filament according to any one of items 70 to 80, wherein the polyhydroxyalkanoate is selected from polyhydroxybutyrate-co-hydroxyhexanoate, polyhydroxybutyrate, polyhydroxyvalerate, polyhydroxybutyrate-co-hydroxyvalerate, and any combination thereof.

[0297] 82. The filament according to any one of items 70 to 81, wherein the polyhydroxyalkanoate is selected from poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), poly-3-hydroxybutyrate (P3HB), poly-4-hydroxybutyrate (P4HB), poly-3-hydroxyvalerate (PHV), poly(3-hydroxybutyrate-co-4-hydroxybutyrate), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), and any combination thereof.

[0298] 83. The filament according to any one of items 70 to 82, wherein the polyhydroxyalkanoate is polyhydroxybutyrate-co-hydroxyhexanoate.

[0299] 84. The filament according to any one of items 70 to 83, wherein the polyhydroxyalkanoate is poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

[0300] 85. The filament according to any one of items 70 to 84, wherein the filament comprises, based on a total amount of the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate of 100% by weight, the polyhydroxyalkanoate in an amount of 1% to 25% by weight.

[0301] 86. The filament according to any one of items 70 to 85, wherein, based on a total amount of 100% by weight of the aliphatic polyester, the aromatic-aliphatic polyester, and the polyhydroxyalkanoate, the filament comprises 42% to 62% by weight of the aliphatic polyester, 26% to 46% by weight of the aromatic-aliphatic polyester, and 2% to 22% by weight of the polyhydroxyalkanoate.

[0302] 87. The filament according to any one of items 70 to 86, wherein the aliphatic polyester is polybutylene succinate (PBS), the aliphatic-aromatic polyester is polybutylene terephthalate adipate (PBAT), and the polyhydroxyalkanoate is poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

[0303] 88. The filament according to any one of items 70 to 87, wherein the polyhydroxyalkanoate is partially or wholly replaced by polylactide.

[0304] 89. The filament according to any one of items 70 to 88, wherein the fiber further comprises at least one additive.

[0305] 90. The filament according to item 89, wherein the at least one additive is selected from flame retardants, matting agents, fluorescent markers, antimicrobial agents, plasticizers, fillers, and any combination thereof.

[0306] 91. The filament according to item 90, wherein the additive is a flame retardant.

[0307] 92. The filament according to item 91, wherein the flame retardant is a phosphate selected from: ammonium dihydrogen phosphate ([NH4][H2PO4]), diammonium hydrogen phosphate ([NH4]2[HPO4]), triammonium phosphate ([NH4]3[PO4]), and ammonium polyphosphate and any combination thereof.

[0308] 93. The filament according to item 92, wherein the phosphate is diammonium hydrogen phosphate ([NH4]2[HPO4]).

[0309] 94. The filament according to any one of items 90 to 93, wherein, based on a total weight of 100% by weight of the filament, the fiber contains 0.01 to 5% by weight, preferably 0.1 to 4% by weight, more preferably 0.2 to 3% by weight, and even more preferably 0.3 to 2% by weight of a flame retardant.

[0310] 95. The filament according to item 90, wherein the additive is a matting agent.

[0311] 96. The filament according to item 95, wherein the matting agent is zinc sulfide.

[0312] 97. The filament according to item 90, wherein the additive is a fluorescent marker.

[0313] 98. The filament according to item 90, wherein the additive is an antimicrobial agent.

[0314] 99. The filament according to item 98, wherein the antimicrobial agent is zinc encapsulated in polyethylene terephthalate.

[0315] 100. The filament according to item 90, wherein the additive is a filler.

[0316] 101. The filament according to item 100, wherein the filler is or comprises lignin.

[0317] 102. The filament according to any one of items 89 to 101, wherein, based on a total weight of 100% by weight, the filament contains 15% by weight or less, preferably 10% by weight or less, more preferably 7% by weight or less, even more preferably 5% by weight or less, even more preferably 4% by weight or less, even more preferably 3 to 4% by weight.

[0318] 103. The filament according to any one of items 70 to 102, wherein the diameter of the filament is 1.0 mm or greater, preferably 1.5 mm or greater, more preferably 1.6 mm or greater, and even more preferably 1.7 mm or greater; and

[0319] The diameter of the filament is 5.0 mm or less, preferably 4.0 mm or less, more preferably 3.5 mm or less, and even more preferably 3.0 mm or less.

[0320] 104. The filament according to item 103, wherein the diameter of the filament is in the range of 1.70 mm to 1.80 mm.

[0321] 105. The filament according to item 103, wherein the diameter of the filament is in the range of 2.80 mm to 3.05 mm.

[0322] 106. The filament according to any one of items 70 to 105, wherein the filament is biodegradable according to EN 13432.

[0323] 107. The filament according to any one of items 70 to 106, wherein said filament is not:

[0324] Fibers obtained by a method including the following steps or by a method including the following steps:

[0325] - The melts of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates are spun through hollow fiber spinning nozzles to obtain precursor fibers; and

[0326] - The precursor fiber is obtained by cooling it under a temperature gradient.

[0327] 108. The filament according to any one of items 70 to 107, wherein said filament is not:

[0328] Fibers made from a mixture of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates.

[0329] The fiber comprises two parts in the longitudinal direction, wherein one part is a thicker part and the other part is a thinner part, wherein the thicker part and the thinner part extend in a direction perpendicular to the longitudinal direction of the fiber, and wherein the extension of the thicker part in the vertical direction is greater than the extension of the thinner part in the vertical direction.

[0330] The thicker portion has at least a cavity, and the thinner portion has at least a dense structure.

[0331] 109. The filament according to any one of items 70 to 108, wherein said filament is not:

[0332] Hollow fibers made from a mixture of aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates.

[0333] 110. The filament according to any one of items 70 to 109, wherein the filament is not a segmented fiber or a segmented hollow fiber.

[0334] 111. A roller comprising a filament suitable for 3D printing according to any one of items 70 to 110.

[0335] 112. A cartridge for a 3D printer, comprising a filament suitable for 3D printing according to any one of claims 70 to 110.

[0336] 113. A three-dimensional printed article which can be obtained by or through three-dimensional printing of a filament suitable for three-dimensional printing according to any one of items 70 to 110.

[0337] 114. A method for preparing a filament suitable for three-dimensional printing according to any one of items 70 to 110, comprising extruding a melt comprising an aliphatic polyester, an aliphatic-aromatic polyester and a polyhydroxyalkanoate into a filament form.

[0338] 114a. The method according to item 114, wherein the temperature of the melt is in the range of 200°C to 260°C, preferably in the range of 220°C to 250°C, more preferably in the range of 230°C to 250°C, and even more preferably in the range of 230°C to 240°C.

[0339] 115. The method according to item 114, wherein the melt contains 30% to 70% by weight of the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate, based on a total amount of 100% by weight.

[0340] 116. The method according to item 114 or 115, wherein the melt comprises 10% to 60% by weight of the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate, based on a total amount of 100% by weight.

[0341] 117. The method according to any one of items 114 to 116, wherein the melt contains 1% to 25% by weight of polyhydroxyalkanoate based on a total amount of 100% by weight of the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate.

[0342] 118. The method according to any one of items 114 to 117, wherein the melt comprises 42% to 62% by weight of aliphatic polyester, 26% to 46% by weight of aromatic-aliphatic polyester and 2% to 22% by weight of polyhydroxyalkanoate, based on a total amount of 100% by weight of aliphatic polyester, aromatic-aliphatic polyester and polyhydroxyalkanoate.

[0343] 119. The method according to any one of items 114 to 118, wherein the polyhydroxyalkanoate is partially or completely replaced by polylactide.

[0344] 120. The method according to any one of items 114 to 119, wherein the melt further comprises at least one additive.

[0345] 121. The method according to item 120, wherein the at least one additive is selected from flame retardants, matting agents, fluorescent markers, antimicrobial agents, plasticizers, fillers, and any combination thereof.

[0346] 122. The method according to item 121, wherein the additive is a flame retardant.

[0347] 123. The method according to item 122, wherein, based on the total weight of the melt being 100% by weight, the melt contains 0.01 to 5% by weight, preferably 0.1 to 4% by weight, more preferably 0.2 to 3% by weight, and even more preferably 0.3 to 2% by weight of a flame retardant.

[0348] 124. The method according to any one of items 120 to 123, wherein the total amount of the additive is 15% by weight or less, preferably 10% by weight or less, more preferably 7% by weight or less, even more preferably 5% by weight or less, even more preferably 4% by weight or less, even more preferably 3 to 4% by weight.

[0349] 125. The method according to any one of items 114 to 124, wherein the method is not:

[0350] A method for preparing fibers, comprising:

[0351] - The melts of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates are spun through hollow fiber spinning nozzles to obtain precursor fibers; and

[0352] - The precursor fiber is obtained by cooling it under a temperature gradient.

[0353] 126. A filament which can be obtained by or through any one of items 114 to 125.

[0354] 127. Use of a melt comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates for the preparation of filaments suitable for three-dimensional printing, wherein the filaments are as defined in any of items 70 to 110.

[0355] 128. Use of melts comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates for the preparation of filaments suitable for 3D printing.

[0356] 129. Use of mixtures comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates for the preparation of filaments suitable for three-dimensional printing, wherein the filaments are as defined in any of items 70 to 110.

[0357] 130. Use of mixtures comprising aliphatic polyesters, aliphatic-aromatic polyesters and polyhydroxyalkanoates for the preparation of filaments suitable for 3D printing.

[0358] The following examples will provide a better understanding of the invention and its advantages; these examples are provided for illustrative purposes only. These examples do not limit the scope of the invention in any way.

[0359] Example

[0360] Example 1: Preparation of fibers according to an embodiment of the present invention

[0361] According to an embodiment of the present invention, fibers are prepared using the following components (a masterbatch of polymer I, polymer II, polymer III, and additives):

[0362] Polymer I Polybutylene succinate (PBS, Mitsubishi Chemical BioPBS FZ71, bio-based)

[0363] Polymer II Polybutylene adipate terephthalate (PBAT, BASF ECOFLEX PBAT)

[0364] Polymer III Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PBHB, KANEKA AONILEX151A, bio-based)

[0365] Masterbatch The masterbatch includes the amount of additives shown in Table 1 below.

[0366] Table 1

[0367] 10% by weight Zinc sulfide (Kremer Zinksulfid 46350, Kremer Pigments GmbH, Eichstein, Germany) Fiber matting, increasing melting point 22% by weight <![CDATA[Ammonium dibasic phosphate ((NH4)2HPO4) (EMSURE®, Sigma Aldrich product number 1.01207, Millipore)]]> Flame retardant 50 PPB Fluorescent particles (oligomers from Polysecure GmbH, Freiburg, Germany) Tokens used for authentication 13% by weight SMARTZINC 213 PET hot melt adhesive (zinc encapsulated in polyethylene terephthalate, Smartpolymer GmbH, Rudolstadt, Germany) Antibacterial agents 55% by weight Filler (Wood-Plastic Composite (WPC)) High-Purity Lignin Free of Copper Arsenic Chromate (CCA) GRAANUL Biotech (Switzerwoods), Tallinn, Estonia filler 100% by weight (total)

[0368] Fibers according to embodiments of the invention were prepared using a Fourné pilot melt spinning test machine (constructed in 2013, Fournémachinenbau GmbH, Alfter-Impekweat, Germany), the melt spinning test machine having a module for side-flow feeding of masterbatch additives, spinning nozzles (any spinning nozzle suitable for melt spinning of fibers can be used; in this example, the nozzle has a circular orifice and is not a hollow fiber spinning nozzle) and a fiber finishing line. Further external treatment was performed on the fiber finishing line using the following steps: reed, inlet structure, immersion bath, drafting system I, stretching bath, drafting system II, steaming, drafting system III, regeneration roller, crimping, drying, and short fiber cutter.

[0369] Polymer I (15,600 g, polybutylene succinate (PBS)), polymer II (10,800 g, polybutylene adipate terephthalate (PBAT)), and polymer III (3,600 g, poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH)) were added in granular form to the melt spinning machine. Additionally, 1,650 kg of powdered masterbatch (additive) was added to the side-flow feed module via a simple screw feeder. The moisture content was approximately 0.1% by weight. Polymers I, II, and III, as well as the masterbatch (additive), were dried in a vacuum drying oven at 60°C for 24 hours prior to addition.

[0370] Use the following process parameters:

[0371] Flow rate: 2.5 kg / h to 5.12 m / min of filament bundle;

[0372] Processing temperature: 230 to 250°C (e.g., 235°C);

[0373] Distance between spinning nozzle and guide roller: 200 cm;

[0374] Guide wire spool: 85℃, 800m / min;

[0375] Guide roller 1: 80℃, 980m / min;

[0376] Guide roller 2: 80℃, 1350m / min;

[0377] Air cooling is used to provide airflow to the precursor fibers from both sides.

[0378] Figure 1 The melt spinning equipment and methods for preparing fibers are illustrated schematically. Figure 1 The melt spinning apparatus includes a spinning nozzle 1 with circular spinnerets. Using an extruder, a melt containing three polymers (processed at 250°C in this embodiment) is spun through the spinning nozzle 1 (not a hollow fiber spinning nozzle in this embodiment) to obtain hot precursor fibers 3. Airflow 7 is provided from both sides onto the precursor fibers 3 to cool them; the airflow 7 may be provided by air-cooled aggregates, schematically represented by snowflakes. In this embodiment, the air used for the airflow 7 has an ambient temperature (approximately 20°C). Air cooling produces fibers 11, which are then wound through guide rollers 13.

[0379] Figure 2 This illustrates an extended scheme for preparing fibers according to an embodiment of the invention and for further processing the fibers through post-treatment. For example... Figure 2 As shown, fibers can be processed, cut, and compressed into packages.

[0380] Example 2: Antimony Content Test

[0381] The antimony content of the fibers obtained, for example in Example 1, was tested in the laboratory of Dr. Matt Schaan Liechtenstein. In principle, the toxic element antimony can exist as a residue of the catalyst used in the polymer production process.

[0382] The antimony content was tested as follows:

[0383] The fibers of Example 1 were inserted into water and (a) heated to the boiling point of the water; (b) stored in water for 8 weeks; and (c) further stored in a glass containing water and air for 4 weeks (sealed, 1 / 3 air, 2 / 3 water).

[0384] Antimony was not detected in the fibers and water (antimony S6 < 0.1 mg / kg ICP-MS). Therefore, this test demonstrates that fibers can be prepared without the use of toxic antimony.

[0385] Example 3: Other characteristics of fibers according to embodiments of the present invention

[0386] Other properties of the fibers according to embodiments of the present invention (obtained as described in Example 1) compared to known commercially available fibers used in the production of textiles are listed in Table 2 below.

[0387] Table 2

[0388] Main products Flame retardant (B1) hydrophilic Antimony-free Biodegradable EN13432 antifouling anti-wrinkle It may contain a certain proportion of renewable raw materials. Water consumption / kg Land consumption per ton (1000 kg) of fiber Fibers according to embodiments of the present invention* X X X X X X X 0.4% 0.19 Diolen X X 0.5% 0.002 Trevira CS X X X 0.5% 0.002 Tencel X X X X 1.5% 0.24 Viscose (Lenzing) X X X X 2.6% 0.69 cotton X X X X 50% 0.82 wool X X X X X X X 100% 170

[0389] Fibers obtained, for example, as described in Example 1.

[0390] “X” indicates that the corresponding characteristic is met.

[0391] As can be seen from Table 2, the fibers according to embodiments of the present invention can be prepared to possess flame retardancy, hydrophilicity, antimony-free properties, biodegradability conforming to EN 13432 standards, stain resistance, wrinkle resistance, and can contain a certain proportion of renewable raw materials. The preparation of fibers according to embodiments of the present invention requires significantly less water consumption than cotton. Furthermore, the land area required to prepare 1 ton (1000 kg) of fiber according to one embodiment of the present invention is also far less than that required for cotton. Therefore, from an ecological point of view, the fibers according to embodiments of the present invention are advantageous compared to cotton.

[0392] Example 4: Garment comprising fibers according to the embodiments of the present invention

[0393] Fibers according to embodiments of the invention (such as those obtained in Example 1), particularly yarns made from such fibers, have been used in the production of shirts.

[0394] Figure 3 The photograph shows a mixture of particles 15 suitable for injection molding of fibers or filaments according to the present invention. Figure 3 Also depicted are fibers 17 (obtained as described, for example, in Example 1) according to embodiments of the invention and yarns 19 made from the fibers and wound on a spool. Figure 3 Also shown is a shirt 21 made of the said fiber, particularly a shirt made of yarn made of the said fiber, the fiber comprising about 40% fiber according to an embodiment of the invention and about 60% cotton. Figure 4 Photographs showing other views of shirt 21.

[0395] Example 5: Preparation of filaments for 3D printing according to an embodiment of the present invention

[0396] The filaments for 3D printing according to embodiments of the present invention were prepared using the same components as described in Example 1 (polymer I, polymer II, polymer III and masterbatch of additives according to Table 1).

[0397] Polymer I (15,600 g, polybutylene succinate (PBS)), polymer II (10,800 g, polybutylene adipate terephthalate (PBAT)), and polymer III (3,600 g, poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH)) were mixed with 1.650 kg of masterbatch (additive). The moisture content was approximately 0.1% by weight. Polymers I, II, and III, as well as the masterbatch (additive), were dried in a vacuum oven at 60°C for 24 hours prior to addition.

[0398] The melt was prepared and extruded from a nozzle with a diameter of 2.5 mm at a melt temperature of 230-250°C (e.g., 235°C) using a uniaxial melt kneading extruder, and then cooled in water at 40°C to obtain filaments with a diameter of 1.75 mm.

[0399] Figure 3 The text describes a filament 23 suitable for 3D printing according to an embodiment of the invention, which can be prepared as, for example, as described in Example 5.

[0400] Using a material extrusion method, this filament is used to produce plastic cards in the form of credit cards on a conventional 3D printer.

Claims

1. A fiber made from a mixture comprising an aliphatic polyester, an aliphatic-aromatic polyester, and a polyhydroxyalkanoate, wherein the aliphatic polyester comprises aliphatic C2-C... 20 Dicarboxylic acids and aliphatic C2-C 12 Diol.

2. The fiber according to claim 1, wherein the fiber is not a hollow fiber.

3. The fiber according to claim 1 or 2, wherein the aliphatic polyester is selected from polybutylene succinate (PBS), polyethylene oxalate, polyethylene malonate, polyethylene succinate, polypropylene oxalate, polypropylene malonate, polypropylene oxalate, polybutylene oxalate, polybutylene malonate, poly(succinic acid-co-adipate)butylene glycol (PBSA), poly(succinic acid-co-azelate)butylene glycol (PBSAz), poly(succinic acid-co-brasic acid)butylene glycol (PBSBr), and any combination thereof. The aliphatic polyester is preferably selected from polybutylene succinate (PBS), poly(succinic acid-co-adipic acid)butylene glycol (PBSA), poly(succinic acid-co-azelanoic acid)butylene glycol (PBSAz), poly(succinic acid-co-brasic acid)butylene glycol (PBSBr), and any combination thereof. The aliphatic polyester is more preferably polybutylene succinate (PBS). The fiber preferably contains 30 to 70% by weight of the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate, based on a total amount of 100% by weight.

4. The fiber according to any one of the preceding claims, wherein the aliphatic-aromatic polyester comprises C2-C 12 Aliphatic dicarboxylic acids, aromatic dicarboxylic acids and aliphatic C2-C 12 Diol, The aliphatic-aromatic polyester is preferably selected from polybutylene adipate terephthalate (PBAT), polybutylene terephthalate succinate (PBST), polybutylene sebacic acid terephthalate (PBSeT), and any combination thereof. The aliphatic-aromatic polyester is more preferably polybutylene adipate terephthalate (PBAT). The fiber preferably contains 10 to 60% by weight of the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate, based on a total weight of 100% by weight.

5. The fiber according to any one of the preceding claims, wherein the polyhydroxyalkanoate comprises C3-C 18 Hydroxyalkyl carboxylic acid, The polyhydroxyalkanoate mentioned therein is preferably selected from poly(hydroxybutyrate-co-hydroxyhexanoate), polyhydroxybutyrate, polyhydroxyvalerate, poly(hydroxybutyrate-co-hydroxyvalerate), and any combination thereof. The polyhydroxyalkanoate wherein the polyhydroxyalkanoate is more preferably selected from poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), poly-3-hydroxybutyrate (P3HB), poly-4-hydroxybutyrate (P4HB), poly-3-hydroxyvalerate (PHV), poly(3-hydroxybutyrate-co-4-hydroxybutyrate), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), and any combination thereof. The polyhydroxyalkanoate is most preferably poly(hydroxybutyrate-co-hydroxyhexanoate). The preferred polyhydroxyalkanoate is still poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). The fiber preferably contains 1 to 25% by weight of the polyhydroxyalkanoate, based on a total amount of 100% by weight of the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate.

6. The fiber according to any one of the preceding claims, wherein, based on a total amount of 100% by weight of the aliphatic polyester, the aromatic-aliphatic polyester, and the polyhydroxyalkanoate, the fiber comprises 42 to 62% by weight of the aliphatic polyester, 26 to 46% by weight of the aromatic-aliphatic polyester, and 2 to 22% by weight of the polyhydroxyalkanoate.

7. The fiber according to any one of the preceding claims, wherein the aliphatic polyester is polybutylene succinate (PBS), the aliphatic-aromatic polyester is polybutylene adipate terephthalate (PBAT), and the polyhydroxyalkanoate is poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

8. The fiber according to any one of the preceding claims, wherein the polyhydroxyalkanoate is partially or completely replaced by polylactide.

9. The fiber according to any one of the preceding claims, wherein the fiber is a textile fiber.

10. The fiber according to any one of the preceding claims, wherein the fiber further comprises at least one additive, wherein the fiber preferably comprises 15% or less, more preferably 10% or less, more preferably 7% or less, even more preferably 5% or less, even more preferably 4% or less, even more preferably 3 to 4% by weight, based on a total weight of 100% of the fiber.

11. The fiber according to claim 10, wherein the at least one additive is preferably selected from flame retardants, matting agents, fluorescent markers, antimicrobial agents, plasticizers, colorants, fillers, and any combination thereof. The additive may optionally be the flame retardant. The flame retardant is more preferably selected from ammonium dihydrogen phosphate ([NH4][H2PO4]), diammonium hydrogen phosphate ([NH4]2[HPO4]), triammonium phosphate ([NH4]3[PO4]), ammonium polyphosphate, and phosphates of any combination thereof. The phosphate is more preferably diammonium hydrogen phosphate ([NH4]2[HPO4]), or The fibers, based on a total fiber weight of 100% by weight, more preferably contain 0.01 to 5% by weight, more preferably 0.1 to 4% by weight, more preferably 0.2 to 3% by weight, and even more preferably 0.3 to 2% by weight of a flame retardant, and / or The additive is optionally a matting agent, wherein the matting agent is preferably zinc sulfide, and / or the additive is optionally a fluorescent marker, and / or the additive is optionally an antimicrobial agent, wherein the antimicrobial agent is preferably zinc encapsulated in polyethylene terephthalate, and / or the additive is optionally a filler, wherein the filler is preferably lignin or contains lignin.

12. The fiber according to any one of the preceding claims, wherein the fiber fineness is 0.5 to 8 denier, preferably 0.8 to 6 denier, more preferably 0.9 to 3 denier, even more preferably 1.0 to 2 denier, even more preferably 1.0 to 1.5 denier, even more preferably 1.1 to 1.2 denier.

13. The fiber according to any one of the preceding claims, wherein the fiber is a short fiber. The fibers preferably have a short fiber length of 2 to 80 mm, more preferably 5 to 70 mm, more preferably 10 to 60 mm, even more preferably 15 to 50 mm, even more preferably 20 to 40 mm, even more preferably 22 to 35 mm, even more preferably 25 to 32 mm.

14. The fiber according to any one of claims 1 to 12, wherein the fiber is a filament.

15. The fiber according to any one of the preceding claims, wherein the fiber is biodegradable according to EN 13432.

16. The fiber according to any one of the preceding claims, wherein the fiber is not: Fibers obtained by a method including the following steps or by a method including the following steps: - A melt containing aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate is spun through a hollow fiber spinning nozzle to obtain precursor fibers; and - Cooling the precursor fibers under a temperature gradient to obtain fibers and / or The fibers described therein are not: Fibers made from a mixture of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates. in, The fiber comprises two parts in the longitudinal direction, wherein one part is a thicker part and the other part is a thinner part, wherein the thicker part and the thinner part extend in a direction perpendicular to the longitudinal direction of the fiber, and wherein the extension of the thicker part in the vertical direction is greater than the extension of the thinner part in the vertical direction. At least a portion of the thicker portion has a cavity, and at least a portion of the thinner portion has a dense structure and / or The fiber is not a hollow fiber made of a mixture comprising aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate, and / or The fiber is not segmented fiber or segmented hollow fiber.

17. A yarn comprising the fibers of any one of claims 1 to 16.

18. A textile comprising the fiber of any one of claims 1 to 16 or the yarn of claim 17. The textiles mentioned therein are preferably clothing or home textiles. The clothing mentioned therein is preferably selected from shirts, polo shirts, trousers, jackets, underwear, socks, outerwear, shoes, and shoelaces. The home textiles mentioned therein are preferably selected from curtains, carpets, blankets, sheets, comforters, comforter covers, mattress covers and towels.

19. A method for preparing fibers according to any one of claims 1 to 16, comprising: - A melt containing aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate is spun through a spinning nozzle to obtain precursor fibers; as well as - Cooling the precursor fibers to obtain the fibers. Preferably, the temperature of the melt is in the range of 200°C to 260°C, more preferably in the range of 220°C to 250°C, even more preferably in the range of 230°C to 250°C, and still more preferably in the range of 230°C to 240°C, and / or The cooling is preferably achieved by air cooling. The lipid polyester comprises aliphatic C2-C 20 Dicarboxylic acids and aliphatic C2-C 12 Diol.

20. The method of claim 19, wherein, based on a total amount of 100% by weight of the aliphatic polyester, the aliphatic-aromatic polyester, and the polyhydroxyalkanoate, the melt comprises 30 to 70% by weight of the aliphatic polyester, and / or The melt contains 10 to 60% by weight of the aliphatic polyester, the aliphatic-aromatic polyester, and the polyhydroxyalkanoate, based on a total amount of 100% by weight. in, Based on a total weight of 100% by weight of the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate, the melt contains 1% to 25% by weight of the polyhydroxyalkanoate.

21. The method according to any one of claims 19 or 20, wherein, Based on a total weight of 100% by weight of the aliphatic polyester, the aromatic-aliphatic polyester, and the polyhydroxyalkanoate, the melt contains 42 to 62% by weight of the aliphatic polyester, 26 to 46% by weight of the aromatic-aliphatic polyester, and 2 to 22% by weight of the polyhydroxyalkanoate.

22. The method according to any one of claims 19 to 21, wherein, The polyhydroxyalkanoate is partially or completely replaced by polylactide.

23. The method according to any one of claims 19 to 22, wherein, The melt also contains at least one additive. Wherein, based on a total melt weight of 100% by weight, the total amount of the additive is preferably 15% by weight or less, more preferably 10% by weight or less, more preferably 7% by weight or less, even more preferably 5% by weight or less, even more preferably 4% by weight or less, even more preferably 3 to 4% by weight. The at least one additive is preferably selected from flame retardants, matting agents, fluorescent markers, antimicrobial agents, plasticizers, fillers, and any combination thereof. The additive is optionally a flame retardant, and preferably, the melt contains 0.01 to 5% by weight, more preferably 0.1 to 4% by weight, more preferably 0.2 to 3% by weight, and even more preferably 0.3 to 2% by weight, based on a total weight of 100% of the melt.

24. The method according to any one of claims 19 to 23, wherein the fiber is prepared as a short fiber, or wherein the fiber is prepared as a filament.

25. The method according to any one of claims 19 to 24, wherein the spinning nozzle is not a hollow fiber spinning nozzle, and / or wherein the method is not: Methods for preparing fibers include: - A melt containing aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate is spun through a hollow fiber spinning nozzle to obtain precursor fibers; as well as - The precursor fiber is cooled under a temperature gradient to obtain the fiber.

26. A fiber that can be obtained by or through the method of any one of claims 19 to 25, wherein preferably the fiber is not a hollow fiber.

27. Use of a melt comprising an aliphatic polyester, an aliphatic-aromatic polyester, and a polyhydroxyalkanoate for the preparation of fibers, wherein the aliphatic polyester comprises aliphatic C2-C... 20 Dicarboxylic acids and aliphatic C2-C 12 Diol, wherein the fiber is preferably defined as in any one of claims 1 to 16.

28. Use of a mixture comprising aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate for the preparation of fibers, wherein the aliphatic polyester comprises aliphatic C2-C 20 Dicarboxylic acids and aliphatic C2-C 12 Diol, wherein the fiber is preferably defined as in any one of claims 1 to 16.

29. A filament suitable for 3D printing, comprising a mixture of aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate, wherein the aliphatic polyester comprises aliphatic C2-C... 20 Dicarboxylic acids and aliphatic C2-C 12 Diol.

30. The filament according to claim 29, wherein the aliphatic polyester is selected from polybutylene succinate (PBS), polyethylene oxalate, polyethylene malonate, polyethylene succinate, polypropylene oxalate, polypropylene malonate, polypropylene oxalate, polybutylene oxalate, polybutylene malonate, poly(succinic acid-co-adipate)butylene glycol (PBSA), poly(succinic acid-co-azelate)butylene glycol (PBSAz), poly(succinic acid-co-brasic acid)butylene glycol (PBSBr), and any combination thereof. The aliphatic polyester is preferably selected from polybutylene succinate (PBS), poly(succinic acid-co-adipate)butylene glycol (PBSA), poly(succinic acid-co-azelate)butylene glycol (PBSAz), poly(succinic acid-co-brasic acid)butylene glycol (PBSBr), and any combination thereof. The aliphatic polyester is more preferably polybutylene succinate (PBS). The filament preferably comprises 30% to 70% by weight of aliphatic polyester, based on a total amount of 100% of the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate.

31. The filament according to any one of claims 29 or 30, wherein the aliphatic-aromatic polyester comprises C2-C 12 Aliphatic dicarboxylic acids, aromatic dicarboxylic acids, and aliphatic C2-C 12 Diol, The aliphatic-aromatic polyester is preferably selected from polybutylene adipate terephthalate (PBAT), polybutylene terephthalate succinate (PBST), polybutylene sebacic acid terephthalate (PBSeT), and any combination thereof. The aliphatic-aromatic polyester is more preferably polybutylene adipate terephthalate (PBAT). The filament preferably comprises 10% to 60% by weight of the aliphatic-aromatic polyester, based on a total amount of 100% by weight of the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate.

32. The filament according to any one of claims 29 to 31, wherein the polyhydroxyalkanoate comprises C3-C 18 Hydroxyalkyl carboxylic acid, The polyhydroxyalkanoate mentioned therein is preferably selected from polyhydroxybutyrate-co-hydroxyhexanoate, polyhydroxybutyrate, polyhydroxyvalerate, polyhydroxybutyrate-co-hydroxyvalerate, and any combination thereof. The polyhydroxyalkanoate wherein the polyhydroxyalkanoate is more preferably selected from poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), poly-3-hydroxybutyrate (P3HB), poly-4-hydroxybutyrate (P4HB), poly-3-hydroxyvalerate (PHV), poly(3-hydroxybutyrate-co-4-hydroxybutyrate), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), and any combination thereof. The polyhydroxyalkanoate is more preferably polyhydroxybutyrate-co-hydroxyhexanoate. The most preferred polyhydroxyalkanoate is poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH). The filament preferably comprises 1 to 25% by weight of polyhydroxyalkanoate based on a total weight of 100% by weight of the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate.

33. The filament according to any one of claims 29 to 32, wherein, based on a total weight of 100% by weight of the aliphatic polyester, the aliphatic-aromatic polyester, and the polyhydroxyalkanoate, the filament comprises 42% to 62% by weight of the aliphatic polyester, 26% to 46% by weight of the aromatic-aliphatic polyester, and 2% to 22% by weight of the polyhydroxyalkanoate.

34. The filament according to any one of claims 29 to 33, wherein the aliphatic polyester is polybutylene succinate (PBS), the aliphatic-aromatic polyester is polybutylene terephthalate adipate (PBAT), and the polyhydroxyalkanoate is poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH).

35. The filament according to any one of claims 29 to 34, wherein the polyhydroxyalkanoate is partially or wholly replaced by polylactide.

36. The filament according to any one of claims 29 to 35, wherein the fiber further comprises at least one additive, wherein the filament preferably comprises 15% by weight or less, preferably 10% by weight or less, more preferably 7% by weight or less, even more preferably 5% by weight or less, even more preferably 4% by weight or less, even more preferably 3 to 4% by weight, based on 100% by weight of the total weight of the filament.

37. The filament according to claim 36, wherein the at least one additive is preferably selected from flame retardants, matting agents, fluorescent markers, antimicrobial agents, plasticizers, fillers, and any combination thereof. The additives mentioned therein are optionally flame retardants, and The flame retardant is preferably selected from diammonium dihydrogen phosphate ([NH4][H2PO4]), diammonium hydrogen phosphate ([NH4]2[HPO4]), triammonium phosphate ([NH4]3[PO4]), ammonium polyphosphate, and phosphates of any combination thereof, and the phosphate is more preferably diammonium hydrogen phosphate ([NH4]2[HPO4]). Based on 100% by weight of the total weight of the filaments, the fibers more preferably contain 0.01 to 5% by weight, preferably 0.1 to 4% by weight, more preferably 0.2 to 3% by weight, and even more preferably 0.3 to 2% by weight of a flame retardant, and / or The additive is optionally a matting agent, preferably zinc sulfide, and / or the additive is optionally a fluorescent marker, and / or the additive is optionally an antimicrobial agent, preferably zinc encapsulated in polyethylene terephthalate, and / or the additive is optionally a filler, preferably lignin or containing lignin.

38. The filament according to any one of claims 29 to 37, wherein the diameter of the filament is 1.0 mm or greater, preferably 1.5 mm or greater, more preferably 1.6 mm or greater, and even more preferably 1.7 mm or greater; and / or The diameter of the filament is 5.0 mm or less, preferably 4.0 mm or less, more preferably 3.5 mm or less, and even more preferably 3.0 mm or less, and / or The diameter of the filament is preferably in the range of 1.70 mm to 1.80 mm, and / or The diameter of the filament is preferably in the range of 2.80 to 3.05 mm.

39. The filament according to any one of claims 29 to 38, wherein the filament is biodegradable according to EN 13432.

40. The filament according to any one of claims 29 to 39, wherein the filament is not: Fibers obtained by a method including the following steps or by a method including the following steps: - A melt containing aliphatic polyester, aliphatic-aromatic polyester, and polyhydroxyalkanoate is spun through a hollow fiber spinning nozzle to obtain precursor fibers; and - Cooling the precursor fibers under a temperature gradient to obtain fibers and / or The filaments mentioned therein are not: Fibers made from a mixture of aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates. in, The fiber comprises two portions in the longitudinal direction, wherein one portion is a thicker portion and the other portion is a thinner portion, wherein the thicker portion and the thinner portion extend in a direction perpendicular to the longitudinal direction of the fiber, and wherein the extension of the thicker portion in the vertical direction is greater than the extension of the thinner portion in the vertical direction. At least a portion of the thicker portion has a cavity, and at least a portion of the thinner portion has a dense structure and / or The filaments mentioned therein are not: Hollow fibers made from a mixture comprising aliphatic polyesters, aliphatic-aromatic polyesters, and polyhydroxyalkanoates; and / or The filaments therein are not segmented fibers or segmented hollow fibers.

41. A roller comprising the filament suitable for three-dimensional printing as claimed in any one of claims 29 to 40.

42. A hopper for a 3D printer, comprising a filament suitable for 3D printing according to any one of claims 29 to 40.

43. A three-dimensional printed article, which can be obtained or obtained therefrom by subjecting a filament suitable for three-dimensional printing according to any one of claims 29 to 40 to three-dimensional printing.

44. A method for preparing a filament suitable for three-dimensional printing according to any one of claims 29 to 40, comprising extruding a melt comprising an aliphatic polyester, an aliphatic-aromatic polyester, and a polyhydroxyalkanoate into a filament form. Preferably, the temperature of the melt is in the range of 200°C to 260°C, more preferably in the range of 220°C to 250°C, even more preferably in the range of 230°C to 250°C, and still more preferably in the range of 230°C to 240°C. The aliphatic polyester comprises aliphatic C2-C 20 Dicarboxylic acids and aliphatic C2-C 12 Diol.

45. The method of claim 44, wherein the melt comprises 30 to 70% by weight of the aliphatic polyester based on a total weight of 100% by weight of the aliphatic polyester, the aliphatic-aromatic polyester, and the polyhydroxyalkanoate, and / or The melt contains 10 to 60% by weight of the aliphatic-aromatic compound based on a total weight of 100% by weight of the aliphatic polyester, the aliphatic-aromatic polyester, and the polyhydroxyalkanoate, and / or in, The melt comprises 1% to 25% by weight of the polyhydroxyalkanoate based on a total weight of 100% by weight of the aliphatic polyester, the aliphatic-aromatic polyester and the polyhydroxyalkanoate.

46. ​​The method according to any one of claims 44 or 45, wherein, The melt comprises 42 to 62% by weight of the aliphatic polyester, 26 to 46% by weight of the aromatic-aliphatic polyester, and 2 to 22% by weight of the polyhydroxyalkanoate, based on a total weight of 100% of the aliphatic polyester, the aliphatic-aromatic polyester, and the polyhydroxyalkanoate.

47. The method according to any one of claims 44 to 46, wherein the polyhydroxyalkanoate is partially or wholly replaced by polylactide.

48. The method according to any one of claims 44 to 47, wherein the melt further comprises at least one additive. Preferably, the total amount of the additive is 15% by weight or less based on 100% by weight of the total melt weight, more preferably 10% by weight or less, more preferably 7% by weight or less, even more preferably 5% by weight or less, even more preferably 4% by weight or less, even more preferably 3-4% by weight. The at least one additive is preferably selected from flame retardants, matting agents, fluorescent markers, antimicrobial agents, plasticizers, fillers, and any combination thereof. The additive is more preferably a flame retardant. in, Based on a total melt weight of 100% by weight, the melt preferably contains 0.01 to 5% by weight, more preferably 0.1 to 4% by weight, more preferably 0.2 to 3% by weight, and even more preferably 0.3 to 2% by weight of flame retardant.

49. The method according to any one of claims 44 to 48, wherein the method is not: Methods for preparing fibers include: - A melt containing aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate is spun through a hollow fiber spinning nozzle to obtain precursor fibers; as well as - The precursor fiber is obtained by cooling it under a temperature gradient.

50. A filament, said filament being obtainable by or through any one of claims 44 to 49.

51. Use of a melt comprising an aliphatic polyester, an aliphatic-aromatic polyester, and a polyhydroxyalkanoate for preparing filaments suitable for three-dimensional printing, wherein the aliphatic polyester comprises aliphatic C2-C... 20 Dicarboxylic acids and aliphatic C2-C 12 Diol, wherein the filament is preferably defined as in any one of claims 29 to 40.

52. Use of a mixture comprising aliphatic polyester, aliphatic-aromatic polyester and polyhydroxyalkanoate for the preparation of filaments suitable for 3D printing, wherein the aliphatic polyester comprises aliphatic C2-C 20 Dicarboxylic acids and aliphatic C2-C 12 Diol, wherein the filament is preferably defined as in any one of claims 29 to 40.

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