A 3D mesh structure having high elasticity, a soft touch, and good quietness, and a method for preparing the same.

Abstract

The present invention relates to a 3D network structure comprising thermoplastic polyurethane, wherein the thermoplastic polyurethane has a hard phase ratio in the range of 10% to 40% by weight, and the thermoplastic polyurethane is 10 3 Pa·s to 10 5 The invention also relates to an article having a viscosity in the range of Pa·s and a processing temperature window.

Description

[Technical Field]

[0001] The present invention relates to a three-dimensional (3D) network structure containing thermoplastic polyurethane, and a method for preparing a 3D network structure.

[0002] Background technology Three-dimensional (3D) mesh has a 3D network structure and is widely applied, for example, in mattresses and chair cushions. Currently, 3D mesh is mainly made of polyethylene (PE), polyolefin elastomer (POE), or thermoplastic polyether ester elastomer (TPEE). However, such 3D mesh has poor tactile properties and noise reduction.

[0003] Thermoplastic polyurethane (TPU) is a type of elastomer with excellent properties such as high strength, high toughness, abrasion resistance, oil resistance, antibacterial properties, and good processability, and is widely used in many fields, including sports, medicine, and food. However, there are very few patents disclosing the application of TPU in 3D mesh.

[0004] U.S. Patent Application Publication No. 2015 / 0087196 discloses an elastic network structure including a three-dimensional random loop joint structure made from a continuous linear structure. This patent generally refers to the thermoplastic resin for forming the network structure as at least one thermoplastic resin selected from the group consisting of flexible polyolefins, polystyrene thermoplastic elastomers, polyester thermoplastic elastomers, polyurethane thermoplastic elastomers, and polyamide thermoplastic elastomers, and provides several specific examples for preparing a network structure using a polyester thermoplastic elastomer. However, this document does not provide any examples for preparing a network structure using a polyurethane thermoplastic elastomer.

[0005] U.S. Patent Application Publication No. 2016 / 0237603 discloses a mesh structure made from a three-dimensional random loop joint structure obtained by forming random loops by curling a continuous linear structure containing at least one thermoplastic elastic resin selected from the group consisting of polyolefin thermoplastic elastomers, ethylene vinyl acetate copolymers, polyurethane thermoplastic elastomers, and polyamide thermoplastic elastomers. This document measures the repeated compression durability and rebound properties of the resulting cushion. However, this document does not address the tactile feel and quietness of the cushion.

[0006] For the application of 3D mesh structures, high elasticity, a soft touch, and good quietness are important; therefore, there remains a need to provide 3D mesh structures that possess high elasticity, a soft touch, and good quietness.

[0007] Summary of the Invention The object of the present invention is to provide a 3D mesh structure that has high elasticity, a soft touch, and good quietness.

[0008] Therefore, the present invention provides a 3D network structure comprising thermoplastic polyurethane, wherein the thermoplastic polyurethane has a hard phase ratio in the range of 10% to 40% by weight, and the thermoplastic polyurethane is 10 3 Pa·s to 10 5 It has a processing temperature window with a viscosity in the range of Pa·s.

[0009] The present invention also provides an article having a 3D mesh structure.

[0010] The 3D mesh structure of the present invention has been found to exhibit high elasticity, a soft touch, and good quietness. [Brief explanation of the drawing]

[0011] [Figure 1] This figure shows the compressive force response of different 3D mesh samples measured by dynamic viscoelasticity measurements.

[0012] Modes for carrying out the invention The present invention will be described in detail below. It should be understood that the present invention can be embodied in many different ways and should not be construed as being limited to the embodiments described herein.

[0013] Unless otherwise defined, all technical and scientific terms used herein have the meanings generally understood by those skilled in the art in which the present invention pertains. Where used herein, the following terms have the meanings described below unless otherwise specified.

[0014] As used herein, the articles "a" and "an" refer to one or more (i.e., at least one) grammatical objects of the article or its constituent component.

[0015] As used herein, terms such as “comprise” and “comprising” are interchangeable with “contain” and “containing,” and should be interpreted in a non-restrictive and open manner. That is, for example, there may be further components or elements. Expressions such as “consists of” or “consists essentially of,” or related expressions, may be encompassed within “comprises” or related expressions.

[0016] Unless otherwise specified, all percentages (%) are "weight percentages".

[0017] Unless otherwise specified, the molecular weight of each component or polymer refers to the number-average molecular weight (Mn).

[0018] In this invention, the molecular weight of each component or polymer was determined using gel permeation chromatography (GPC) in accordance with GB / T21863-2008.

[0019] In the present invention, the OH value of each polyol was determined according to DIN53240.

[0020] In the present invention, the hard phase ratio (wt%) of the TPU is calculated according to the following formula:

Equation

[0025] In this invention, the compression set is measured according to ISO 1856:2018 - Method A, 70°C.

[0026] In this invention, the noise level is measured using the SW6004 digital sound level meter available from Dongguan Wanchuang Electronic Products Co., Ltd., by placing the sound level meter 5 mm away from the 3D mesh sample, repeatedly pressing the 3D mesh sample 20 times, recording the maximum noise level, and then calculating the average of the three measurements to obtain the noise level. A lower noise level indicates better quietness.

[0027] In this invention, the ratio of the stress of a 3D mesh sample at 40% compression to the stress of a 3D mesh sample at 10% compression is defined as a comfort coefficient indicating the comfort level of the 3D mesh sample, and the higher the comfort coefficient, the better the comfort level of the 3D mesh sample.

[0028] In this invention, the soft touch sensation is measured by 10 people (5 women and 5 men aged 20-50) using their hands and classified into a rating range of 1 to 5, where 5 represents the highest (best) soft touch sensation and 1 represents the lowest soft touch sensation.

[0029] Polyol (a) In the present invention, the components for forming thermoplastic polyurethane may include polyols. Polyols can have number-average molecular weights (Mn) in the range of 500 to 5000, preferably 700 to 4000, more preferably 800 to 3000, and most preferably 900 to 1200, such as 600, 900, 1000, 1100, 1200, 1300, 1400, 1500, 2000, 2500, 3000, 3500, 4000, 4500, and 5000.

[0030] The polyol may be a polyol conventionally used in thermoplastic polyurethanes, such as a polyether polyol, a polyester polyol such as a polycaprolactone polyol, a polycarbonate polyol, or a combination thereof, preferably a polyether polyol. Preferably, the polyol may be a polyether diol, a polyester diol, a polycarbonate diol, or a combination thereof.

[0031] The polyols in this invention can be produced by processes known in the art or are commercially available.

[0032] In one embodiment, the polyol may be selected from oxygen-containing heterocyclic compounds containing 2 to 6 carbon atoms, such as 3, 4, 5, or 6 carbon atoms, preferably polyether polyols derived from tetrahydrofuran. Preferably, the polyol is produced by polymerizing tetrahydrofuran as repeating units, preferably with primary hydroxyl groups at the terminals. In a preferred embodiment, polytetrahydrofuran (PTHF) has a functional value of 2, a number-average molecular weight (Mn) of 975 to 1025 g / mol, and an OH value (OHv) of 109.5 to 115.1 mg KOH / g, for example, PTHF1000 from BASF.

[0033] In preferred embodiments, the polyol is selected from polyether polyols derived from epoxides, preferably ethylene oxide, propylene oxide, or mixtures thereof.

[0034] In one embodiment, the polyol may be selected from polyester polyols, for example, those obtained from dicarboxylic acids having 2 to 12 carbon atoms, preferably 4 to 6 carbon atoms, and polyhydric alcohols. Suitable dicarboxylic acids include, for example, aliphatic dicarboxylic acids such as succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, and sebacic acid, or aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, and terephthalic acid. Dicarboxylic acids may be used alone or in mixtures, for example, as a mixture of succinic acid, glutaric acid, and adipic acid. For the preparation of polyester polyols, it is also possible to optionally use corresponding dicarboxylic acid derivatives, such as carboxylic acid diesters, anhydrides, or acid chlorides, having 1 to 4 carbon atoms in the alcohol residue, instead of dicarboxylic acids. Suitable examples of polyhydric alcohols include diols having 2 to 10 carbon atoms, preferably 2 to 6 carbon atoms, such as ethylene glycol, diethylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,10-decanediol, 2,2-dimethyl-1,3-propanediol, 1,3-propanediol, or dipropylene glycol. Depending on the desired properties, polyester polyols can be used alone or in mixtures. Preferred polyester polyols include poly(ethylene glycol adipate), poly(1,4-butanediol adipate), poly(ethylene glycol / 1,4-butanediol adipate), poly(1,6-hexanediol / neopentyl glycol adipate), poly(1,6-hexanediol / 1,4-butanediol adipate), and polycaprolactone, condensation products of ω-hydroxycarboxylic acids, such as ω-hydroxyhexanoic acid, or polymerization products of lactones, such as optionally substituted ω-caprolactone.

[0035] In one embodiment, the polyol may be selected from carbonic acid and diols, particularly polycarbonate polyols derived from diols having 4 to 6 carbon atoms, such as 1,4-butanediol or 1,6-hexanediol.

[0036] The polyol is preferably used in amounts ranging from 45% to 80% by weight, based on the total weight of the thermoplastic polyurethane, such as 45% by weight, 50% by weight, 55% by weight, 60% by weight, 65% by weight, 70% by weight, 75% by weight, and 80% by weight.

[0037] isocyanate (b) In the present invention, components for forming thermoplastic polyurethane may include isocyanates. The isocyanates may include all known isocyanates for producing polyurethane. These isocyanates include tri-, tetra-, penta-, hexa-, hepta- and / or octamethylene diisocyanates, 2-methylpentamethylene 1,5-diisocyanate, 2-ethylbutylene 1,4-diisocyanate, pentamethylene 1,5-diisocyanate, butylene 1,4-diisocyanate, 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane (isophorone diisocyanate, IPDI), 1,4- and / or 1,3-bis(isocyanatomethyl)cyclohexane (HXDI), cyclohexane 1,4-diisocyanate, and 1-methylcyclohexane 2,4- and / or 2,6- The present invention includes aliphatic, alicyclic, aromatic aliphatic and / or aromatic isocyanates, such as diphenylmethane diisocyanate (MDI), polymer MDI, naphthylene 1,5-diisocyanate (NDI), torylene 2,4- and / or 2,6-diisocyanate (TDI), 3,3'-dimethyldiphenyl diisocyanate, 1,2-diphenyltan diisocyanate and / or phenylenedi isocyanate, or mixtures thereof.

[0038] Preferably, the isocyanate includes MDI, particularly 4,4'-diphenylmethane diisocyanate.

[0039] The isocyanate is preferably used in amounts ranging from 15% to 50% by weight, based on the total weight of the thermoplastic polyurethane, such as 15% by weight, 20% by weight, 25% by weight, 30% by weight, 35% by weight, 40% by weight, 45% by weight, and 50% by weight.

[0040] Chain extender (c) In the present invention, the components for forming the thermoplastic polyurethane may include a chain extender.

[0041] The chain extenders that can be used are substances having a molar mass of less than 500 g / mol, more preferably in the range of 60 to 400 g / mol, and the chain extender has two or more (e.g., three) hydrogen atoms that react with the isocyanate. These chain extenders can be used individually or in the form of mixtures. It is preferable to use diols having a molecular weight of less than 500, particularly 60 to 400, specifically 60 to 350. Examples of those that can be used are aliphatic, alicyclic, and / or aromatic aliphatic diols having 2 to 14, preferably 2 to 10 carbon atoms, such as ethylene glycol, 1,3-propanediol, 1,4-butanediol (1,4-BDO), 1,6-hexanediol, 1,10-decanediol, 1,2-, 1,3- and 1,4-dihydroxycyclohexane, diethylene glycol, dipropylene glycol, tripylene glycol, and diethanolamine. Ethylene glycol, 1,3-propanediol, or 1,4-butanediol, particularly 1,4-butanediol, is preferred.

[0042] The chain extender is preferably used in amounts of 1% to 11% by weight, more preferably 3% to 8% by weight, based on the total weight of the thermoplastic polyurethane, such as 1% by weight, 2% by weight, 3% by weight, 4% by weight, 5% by weight, 6% by weight, 7% by weight, 8% by weight, 9% by weight, 10% by weight, and 11% by weight.

[0043] Additives (d) In the present invention, the thermoplastic polyurethane may optionally contain additives.

[0044] Additives that may be used in the present invention include chain modifiers, lubricants, surfactants, preservatives, pigments, colorants, antioxidants, waxes, anti-ultraviolet (UV) additives, stabilizers, thickeners, wetting agents, fillers, and reinforcing agents, or mixtures thereof. When preparing thermoplastic polyurethanes, it is preferable to use one of the above additives or a mixture thereof.

[0045] Additives are generally used in amounts of 0 to 12% by weight, such as 0.1 to 10% by weight, based on the total weight of the thermoplastic polyurethane.

[0046] According to the present invention, preferably, chain modifiers, lubricants, antioxidants, and anti-ultraviolet additives are used. The amount of each of these is preferably 0.1 to 5% by weight, and more preferably 0.1 to 1.5% by weight, based on the total weight of the thermoplastic polyurethane.

[0047] As a chain modifier, it comprises an alkyl alcohol having one hydroxyl group, for example, the number of carbon atoms of the alkyl alcohol may be 2 to 30, preferably 4 to 26, more preferably 10 to 22. An alkyl alcohol having one hydroxyl-terminated group having 10 to 20 carbon atoms, preferably 14 to 18 carbon atoms, particularly 1-tetradecanol is preferred. If present, the amount of chain modifier based on the total weight of the thermoplastic polyurethane is preferably 0.1% to 5% by weight, more preferably 0.1% to 1.0% by weight, such as 0.2% by weight, 0.3% by weight, 0.4% by weight, 0.5% by weight, 0.7% by weight, 0.8% by weight, 0.9% by weight, etc.

[0048] As antioxidants, all compounds commonly used to prepare polyurethanes can be used, such as tea polyphenols (TP), tocopherols, flavonoids, butylhydroxyanisole (BHA), dibutylhydroxytoluene (BHT), and tert-butylhydroquinone (TBHQ). If present, the amount of antioxidant based on the total weight of the thermoplastic polyurethane is preferably 0.2% by weight, 0.3% by weight, 0.4% by weight, 0.5% by weight, 0.7% by weight, 0.8% by weight, 0.9% by weight, 1.0% by weight, 1.2% by weight, 1.3% by weight, 1.4% by weight, etc., ranging from 0.1% to 5% by weight, more preferably 0.1% to 1.5% by weight.

[0049] As a lubricant, all compounds commonly used to prepare polyurethanes can be used. If present, the amount of lubricant based on the total weight of the thermoplastic polyurethane is preferably 0.1% to 5% by weight, more preferably 0.1% to 1.0% by weight, such as 0.2% by weight, 0.3% by weight, 0.4% by weight, 0.5% by weight, 0.7% by weight, 0.8% by weight, 0.9% by weight, etc.

[0050] As an anti-UV additive, all compounds suitable for preparing polyurethanes can be used, such as salicylates, phenyl ketones, benzotriazoles, substituted acrylonitriles, and triazines. If present, the amount of the anti-UV additive based on the total weight of the thermoplastic polyurethane is preferably 0.1% to 5% by weight, more preferably 0.1% to 1% by weight, such as 0.2% by weight, 0.3% by weight, 0.4% by weight, 0.5% by weight, 0.7% by weight, 0.8% by weight, and 0.9% by weight.

[0051] Catalyst (e) In the present invention, the components for forming the thermoplastic polyurethane may optionally include a catalyst (e).

[0052] As catalysts, any compound capable of promoting the reaction between isocyanates and polyols can be used. Such compounds are known and, for example, described in "Kunststoffhandbuch, volume 7, Polyurethane," Carl Hanser Verlag, 1993, 3rd edition, Chapter 3.4.1. These catalysts include amine-based catalysts, organometallic compound-based catalysts, or mixtures thereof.

[0053] As amine catalysts, for example, strongly basic amines such as N,N,N-triethylaminoethoxyethanol, bis(N,N-dimethylaminoethyl) ether, dimethylcyclohexylamine, trimethylhydroxyethylethylenediamine, dimethylbenzylamine, triethylamine, triethylenediamine, pentamethyldipropylenetriamine, dimethylethanolamine, N-methylimidazole, N-ethylimidazole, tetramethylhexamethylenediamine, tris(dimethylaminopropyl)hexahydrotriazine, dimethylaminopropylamine, N-ethylmorpholine, diazabicycloundecene, diazabicyclononene, diazabicyclooctane, preferably triethylenediamine or bis(N,N-dimethylaminoethyl) ether can be used.

[0054] As catalysts based on organometallic compounds, for example, tin(II) salts of organic carboxylic acids, such as tin(II) acetate, tin(II) octanoate, tin(II) ethylhexanoate, and tin(II) laurate, as well as dialkyltin(IV) salts of organic carboxylic acids, such as dibutyltin diacetate, dibutyltin dilaurate, dibutyltin maleate, and dioctyltin diacetate, and furthermore, Zn salts or Bi salts, such as zinc octanoate, bismuth(III) neodecanoate, bismuth 2-ethylhexanoate, and bismuth octanoate, or alkali metal salts of carboxylic acids, such as potassium acetate or potassium formate can be used.

[0055] When used, the catalyst is preferably used in an amount of 0.1 ppm to 500 ppm, more preferably 1 ppm to 100 ppm, based on the total weight of the thermoplastic polyurethane.

[0056] Thermoplastic polyurethane In the present invention, the thermoplastic polyurethane has a hard phase ratio in the range of 10% to 40% by weight, preferably 15% to 40% by weight, and more preferably 20% to 40% by weight, such as 12% by weight, 14% by weight, 15% by weight, 16% by weight, 18% by weight, 20% by weight, 22% by weight, 24% by weight, 26% by weight, 28% by weight, 30% by weight, 32% by weight, 34% by weight, 36% by weight, 38% by weight, and 40% by weight.

[0057] In the present invention, the thermoplastic polyurethane is a thermoplastic polyurethane with a pressure of 2000 Pa·s, 5000 Pa·s, 10000 Pa·s, 15000 Pa·s, 20000 Pa·s, 30000 Pa·s, 40000 Pa·s, 50000 Pa·s, 60000 Pa·s, 70000 Pa·s, 80000 Pa·s, 90000 Pa·s, etc. 3 Pa·s to 10 5 Pa·s, preferably 5 × 10 3 Pa·s to 5×10 4 It has a viscosity range of Pa·s and a processing temperature window.

[0058] In the present invention, the thermoplastic polyurethane has a processing temperature window ranging from 80°C to 260°C, preferably from 120°C to 220°C, and more preferably from 165°C to 190°C, such as 80°C, 100°C, 120°C, 125°C, 130°C, 135°C, 140°C, 145°C, 150°C, 155°C, 160°C, 165°C, 170°C, 175°C, 180°C, 185°C, 190°C, 195°C, 200°C, 205°C, 210°C, 215°C, 220°C, and 230°C. To form a 3D mesh structure, the thermoplastic polyurethane is processed at a temperature within the processing temperature window, preferably at a temperature closer to the lower limit of the processing temperature window.

[0059] In the present invention, the thermoplastic polyurethane has a Shore hardness in the range of 60A to 95A, such as 60A, 65A, 70A, 75A, 80A, 85A, 90A, and 95A, for example, 65A to 95A and 70A to 90A.

[0060] Thermoplastic polyurethanes are generally prepared by reacting a polyol, isocyanate, and chain extender with optional additives and optional catalysts by methods of the art. In one embodiment of the present invention, a TPU resin is prepared by mixing a polyol, isocyanate, and chain extender with additives such as chain modifiers, antioxidants, lubricants, and anti-UV additives. The resulting mixture is pulled onto a conveyor belt and sent to a heating zone having infrared heating elements. After heating, the mixture is shredded / pulverized into pieces / granules and optionally melted by an extruder for further pelletization using an underwater granulation system. Optionally, the resulting granules are further dried through a fluidized bed to further construct their molecular weight and remove absorbed water. Thermoplastic polyurethanes can also be prepared by a reaction extruder process.

[0061] 3D network structure 3D mesh structures are prepared by extruding thermoplastic resin through a die head containing multiple holes to form random 3D structures. Continuous 3D structures are further stacked and joined together to form a continuous 3D mesh. 3D mesh structures can be manufactured by known processes in the art, such as the method described in Taiwan Patent Application Publication No. 201538306, which is incorporated herein by reference.

[0062] In a preferred embodiment, the 3D mesh structure is (1) A step of melting TPU resin granules through a single-screw extruder, (2) A step of converting the molten TPU resin into multiple molten flow paths using a die head, (3) The steps of forming a spiral molten flow and stacking it on the surface of the water bath placed below the die head to form a stacked 3D mesh structure, (4) A step of drawing the stacked 3D mesh structure into a water bath by having two rollers placed on the water surface rotate relative to the water bath for cooling, wherein the distance between the two rollers is set to a target thickness of the 3D mesh structure, (5) The step of removing the formed 3D network structure from the water bath and further drying it to obtain the final product. It is prepared by a blow process that includes [a specific process].

[0063] The 3D mesh structure according to the present invention possesses excellent elasticity, a soft touch, and good quietness. These superior properties make it possible to provide a mesh structure suitable for cushioning materials that can be used in beds, office chairs, furniture, sofas, vehicle seats, floor mats, and the like.

[0064] Embodiment Various embodiments are listed below. It will be understood that the embodiments listed below can be combined with all aspects and other embodiments that fall within the scope of the present invention.

[0065] Embodiment 1. A 3D mesh structure comprising thermoplastic polyurethane, wherein the thermoplastic polyurethane has a hard phase ratio in the range of 10% to 40% by weight, and the thermoplastic polyurethane is 10 3 Pa·s to 10 5 A 3D mesh structure having a processing temperature window with a viscosity in the range of Pa·s.

[0066] Embodiment 2. Components for forming thermoplastic polyurethane are (a) Polyol and (b) Isocyanate and, (c) Chain extender and It includes, preferably, (a) 45% to 80% by weight of polyol, (b) 15% to 50% by weight of isocyanate, (c) 1% to 11% by weight of a chain extender and A 3D network structure according to Embodiment 1, comprising, wherein the weight percentage is based on the sum of the weights of each component.

[0067] Embodiment 3. The 3D network structure according to Embodiment 2, wherein the components for forming the thermoplastic polyurethane further include (d) an additive.

[0068] Embodiment 4. The 3D network structure according to Embodiment 3, wherein the additives include chain modifiers, lubricants, surfactants, preservatives, pigments, colorants, antioxidants, waxes, anti-UV additives, stabilizers, thickeners, wetting agents, fillers, reinforcing agents, or mixtures thereof.

[0069] Embodiment 5. The 3D network structure according to Embodiment 4, wherein the additive is selected from the group consisting of chain regulators, lubricants, antioxidants, anti-ultraviolet additives, or mixtures thereof.

[0070] Embodiment 6. The 3D network structure according to Embodiment 5, wherein the chain modifier is an alkyl monohydric alcohol having 2 to 30 carbon atoms, preferably 4 to 26, and more preferably 10 to 22 carbon atoms.

[0071] Embodiment 7. The thermoplastic polyurethane is 5 × 10 3 Pa·s to 5×10 4 A 3D mesh structure according to any one of embodiments 1 to 6, having a processing temperature window with a viscosity in the range of Pa·s.

[0072] Embodiment 8. A 3D network structure according to any one of Embodiments 1 to 7, wherein the thermoplastic polyurethane has a hard phase ratio in the range of 15% to 40% by weight, preferably 20% to 40% by weight.

[0073] Embodiment 9. A 3D network structure according to any one of Embodiments 1 to 8, wherein the thermoplastic polyurethane is processed at a temperature in the range of 80°C to 260°C, preferably 120°C to 220°C, more preferably 165°C to 190°C, to form a 3D network structure.

[0074] Embodiment 10. A 3D network structure according to any one of Embodiments 1 to 9, wherein the thermoplastic polyurethane has a Shore hardness in the range of 60A to 95A, preferably 65A to 95A, and more preferably 70A to 90A.

[0075] Embodiment 11. A 3D network structure according to any one of Embodiments 2 to 10, wherein the polyol has a number-average molecular weight (Mn) in the range of 500 to 5000, preferably 700 to 4000, more preferably 800 to 3000, and most preferably 900 to 1200.

[0076] Embodiment 12. A 3D network structure according to any one of Embodiments 2 to 11, wherein the polyol is selected from polyether polyols and polyester polyols, preferably, the polyol is selected from an oxygen-containing heterocyclic compound containing 2 to 6 carbon atoms, preferably a polyether polyol derived from tetrahydrofuran, or from an epoxide, preferably a polyether polyol derived from ethylene oxide, propylene oxide, or a mixture thereof.

[0077] Embodiment 13. A 3D network structure according to any one of Embodiments 2 to 12, wherein the polyol has a functional value in the range of 1.5 to 2.5, preferably in the range of 1.8 to 2.1.

[0078] Embodiment 14. A 3D network structure according to any one of Embodiments 2 to 13, wherein the isocyanate comprises an aromatic diisocyanate, preferably diphenylmethane diisocyanate.

[0079] Embodiment 15. A 3D mesh structure according to any one of Embodiments 1 to 14, wherein the 3D mesh structure is a 3D mesh.

[0080] Embodiment 16. An article comprising a 3D mesh structure as described in any one of Embodiments 1 to 15. [Examples]

[0081] Next, the present invention will be described with reference to examples and comparative examples, but these are not intended to limit the present invention.

[0082] raw material PTHF1000 is a polytetrahydrofuran manufactured by BASF.

[0083] MDI (4,4'-diphenylmethane diisocyanate) is an isocyanate manufactured by BASF.

[0084] 1,4-Butanediol (1,4-BDO) is a chain extender.

[0085] 1-Tetradecanol is manufactured by Sasol.

[0086] The polyolefin elastomer (POE) is Toughmer DF940 manufactured by Mitsui Chemicals.

[0087] Preparation of TPU TPU is (1) Optionally, mix an additive (chain modifier) ​​with the polyol to dissolve the additive in the polyol, (2) The step of preheating the mixed polyol and chain extender separately to 80°C and the isocyanate to 50°C, (3) A step of mixing the preheated polyol, chain extender and isocyanate together while stirring vigorously in a container, (4) When the temperature of the mixture reaches 110°C, pour the mixture from the container onto a hot plate set to 135°C for 10 minutes until the mixture solidifies on the TPU plate. (5) Transfer the obtained TPU plate to an oven set to 80°C and anneal it for 12 hours. (6) For further processing to manufacture a 3D mesh, the annealed TPU plate is crushed into granules and Prepared according to a general method including [specific ingredients / methods].

[0088] TPU-A, TPU-B, TPU-C, and TPU-D were prepared by the general method described above, according to the components and quantities shown in Table 1 below. Samples made from TPU-A, TPU-B, and TPU-C are examples according to the present invention, and the sample made from TPU-D is a comparative example. [Table 1]

[0089] The characteristics of the obtained TPU are shown in Table 2 below. [Table 2]

[0090] Table 2 shows that TPU-A, TPU-B, and TPU-C have lower processing temperature windows compared to TPU-D. In particular, TPU-C exhibits the lowest processing temperature window.

[0091] Example 1 - Preparation of 3D mesh samples The 3D mesh sample is (1) A step of melting TPU granules through a single-screw extruder at a specific temperature, (2) A step of converting the molten TPU into multiple molten flow paths using a die head, (3) A step of forming a 3D mesh sample by spiraling the molten material and stacking it on the surface of a water bath located below the die head, wherein the water bath has a temperature of 10°C. (4) A step of drawing the stacked 3D mesh sample into a water bath by having two rollers placed on the water surface rotate relative to the water bath for cooling, wherein the distance between the two rollers is set to the target thickness of the 3D mesh sample, the linear velocity of the two rollers is 1 m / min, and the distance between the two rollers is 5 cm. (5) The step of removing the formed 3D mesh sample from the water bath and further drying it at room temperature (RT) to obtain the final product. Prepared by a general blowing process including [unspecified element].

[0092] 3D Mesh Sample A 3D mesh sample A was prepared by the above general blow process in which TPU-A granules were melted by a single-screw extruder at a temperature of 180°C in step (1).

[0093] 3D Mesh Sample B-1 3D mesh sample B-1 was prepared by the above general blow process in which TPU-B granules were melted by a single-screw extruder at a temperature of 190°C in step (1).

[0094] 3D Mesh Sample B-2 3D mesh sample B-2 was prepared by the above general blow process in which TPU-B granules were melted by a single-screw extruder at a temperature of 180°C in step (1).

[0095] 3D Mesh Sample C-1 3D mesh sample C-1 was prepared by the above general blow process in which TPU-C granules were melted by a single-screw extruder at a temperature of 180°C in step (1).

[0096] 3D Mesh Sample C-2 3D mesh sample C-2 was prepared by the above general blow process in which TPU-C granules were melted by a single-screw extruder at a temperature of 170°C in step (1).

[0097] 3D Mesh Sample D 3D mesh sample D was prepared by the above general blow process in which TPU-D granules were melted by a single-screw extruder at a temperature of 190°C in step (1).

[0098] 3D Mesh Sample E 3D mesh sample E was prepared by the above general blow process, in which POE granules were melted by a single-screw extruder at a temperature of 190°C to 200°C.

[0099] The obtained 3D mesh samples B-1, B-2, C-1, and C-2 were tested according to the industrial standard fatigue test in accordance with DIN EN ISO 2439,B, and the results are shown in Table 3 below. [Table 3]

[0100] As shown in Table 3, all 3D mesh samples exhibited good compressive hardness performance. Furthermore, 3D mesh sample B-2, prepared at a lower temperature, showed a lower rate of change in compressive hardness compared to 3D mesh sample B-1. It also indicated that 3D mesh samples prepared at lower temperatures exhibited more consistent performance throughout their lifespan, with a relatively low rate of change in compressive hardness after fatigue testing. [Table 4]

[0101] As shown in Table 4, all 3D mesh samples exhibited lower thickness change rates and better compression set performance. [Table 5]

[0102] As shown in Table 5, TPU-A has the lowest Shore hardness as shown in Table 2, but 3D mesh sample A formed from TPU-A has the highest compressive hardness under 65% deformation. Furthermore, for 3D mesh samples A and C2, the initial compressive hardness at 25% and 40% is much lower than that of 3D mesh sample E, but the compressive hardness at 65% is at the same level as 3D mesh sample E, which indicates a much softer feel at the start of compression and similar load-bearing capacity at the end of compression compared to 3D mesh sample E. Table 5 also shows that comparative 3D mesh sample D has a softer feel at the start of compression, but less load-bearing capacity at the end of compression due to its lower compressive hardness at 65% compression. [Table 6]

[0103] As shown in Table 6, 3D mesh samples A and C2 of the present invention exhibit lower thickness change rates, compression set, and hysteresis losses after fatigue testing, while comparative 3D mesh sample D exhibits higher thickness change rates, compression set, and hysteresis losses after fatigue testing. Furthermore, the lower hysteresis losses of 3D mesh samples A and C2 indicate better elasticity and rebound ability than 3D mesh samples D and E. [Table 7]

[0104] Figure 1 shows the compressive force response of different 3D mesh samples measured by dynamic viscoelasticity measurement (RSA-G2 from TA). As shown in Figure 1 and Table 7, 3D mesh samples A and C2 of the present invention exhibit higher comfort coefficients, which means a better comfort level. [Table 8]

[0105] The average soft-touch sensitivity ratings (ranging from 1 to 5) collected from 10 people (5 women and 5 men aged 20-50) indicate that the 3D mesh sample of the present invention has a better soft-touch feel compared to 3D mesh sample E and comparative 3D mesh sample D. [Table 9]

[0106] As shown in Table 9, 3D mesh samples A and C2 of the present invention exhibit better quietness compared to 3D mesh sample E.

[0107] It will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the scope and spirit of the invention. Embodiments and examples are intended to be considered merely illustrative. Accordingly, the present invention is intended to encompass modifications and variations that fall within the scope of the appended claims and their equivalents.

Claims

1. A 3D network structure comprising thermoplastic polyurethane, wherein the thermoplastic polyurethane has a hard phase ratio in the range of 10% to 40% by weight, and the thermoplastic polyurethane is 10 ３ 10 from Pa・s ５ A 3D mesh structure having a processing temperature window with a viscosity in the range of Pa·s.

2. The components for forming the aforementioned thermoplastic polyurethane are (a) Polyol and (b) Isocyanates and, (c) Chain extender and It includes, preferably, (a) 45% to 80% by weight of polyol, (b) 15% to 50% by weight of isocyanate, (c) 1% to 11% by weight of a chain extender and The 3D network structure according to claim 1, comprising, wherein the weight percentage is based on the sum of the weights of each component.

3. The 3D network structure according to claim 2, wherein the component for forming the thermoplastic polyurethane further comprises (d) an additive.

4. The 3D network structure according to claim 3, wherein the additive comprises a chain regulator, lubricant, surfactant, preservative, pigment, colorant, antioxidant, wax, anti-UV additive, stabilizer, thickener, wetting agent, filler, reinforcing agent, or a mixture thereof.

5. The 3D network structure according to claim 4, wherein the additive is selected from the group consisting of chain regulators, lubricants, antioxidants, anti-ultraviolet additives, or mixtures thereof.

6. The 3D network structure according to claim 5, wherein the chain modifier is an alkyl monohydric alcohol having 2 to 30 carbon atoms, preferably 4 to 26, and more preferably 10 to 22 carbon atoms.

7. The thermoplastic polyurethane is 5 × 10 ３ Pa・s to 5×10 ４ A 3D mesh structure according to any one of claims 1 to 6, having a processing temperature window with a viscosity in the range of Pa·s.

8. The 3D network structure according to any one of claims 1 to 7, wherein the thermoplastic polyurethane has a hard phase ratio in the range of 15% to 40% by weight, preferably 20% to 40% by weight.

9. The 3D network structure according to any one of claims 1 to 8, wherein the thermoplastic polyurethane is processed at a temperature in the range of 80°C to 260°C, preferably 120°C to 220°C, more preferably 165°C to 190°C, so as to form the 3D network structure.

10. The 3D network structure according to any one of claims 1 to 9, wherein the thermoplastic polyurethane has a Shore hardness in the range of 60A to 95A, preferably 65A to 95A, and more preferably 70A to 90A.

11. The 3D network structure according to any one of claims 2 to 10, wherein the polyol has a number-average molecular weight (Mn) in the range of 500 to 5000, preferably 700 to 4000, more preferably 800 to 3000, and most preferably 900 to 1200.

12. The 3D network structure according to any one of claims 2 to 11, wherein the polyol is selected from polyether polyols and polyester polyols, preferably the polyol is selected from an oxygen-containing heterocyclic compound containing 2 to 6 carbon atoms, preferably a polyether polyol derived from tetrahydrofuran, or from an epoxide, preferably a polyether polyol derived from ethylene oxide, propylene oxide, or a mixture thereof.

13. The 3D network structure according to any one of claims 2 to 12, wherein the polyol has a functional value in the range of 1.5 to 2.5, preferably in the range of 1.8 to 2.

1.

14. The 3D network structure according to any one of claims 2 to 13, wherein the isocyanate comprises an aromatic diisocyanate, preferably diphenylmethane diisocyanate.

15. The 3D mesh structure according to any one of claims 1 to 14, wherein the 3D mesh structure is a 3D mesh.

16. An article comprising a 3D mesh structure according to any one of claims 1 to 15.

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