Thermal bonding composite fiber, non-woven fabric containing same, mattress containing same and top cushion

Abstract

The present invention relates to a non-woven fabric, and a mattress and a top pad comprising the same, and more particularly, to a non-woven fabric having a significantly low permanent compression set rate and exhibiting excellent restoring force, and a mattress and a top pad comprising the non-woven fabric.

Description

Technical Field

[0001] The present invention relates to nonwoven fabrics, mattresses and top covers comprising the same, and more specifically, to a nonwoven fabric with a significantly low permanent compression set and exhibiting excellent resilience, and mattresses and top covers comprising the nonwoven fabric. Background Technology

[0002] Generally speaking, polyurethane foam is a foam material manufactured by mixing isocyanates and polyols with blowing agents, catalysts, etc., and simultaneously carrying out foaming and polymerization reactions. This type of polyurethane foam is lightweight and possesses excellent thermal insulation, electrical insulation, chemical resistance, resilience, and durability, thus it is widely used as an elastic material in the field of cushioning materials. However, polyurethane foam also suffers from problems such as yellowing and odor, affecting user comfort, causing environmental hazards, and degrading physical properties.

[0003] On the other hand, besides polyurethane foam, fiber assemblies bonded with environmentally friendly, harmless thermally melt-bonded fibers are also used as elastic materials. Elastomers used as fiber assembly materials are applied in various uses such as packaging containers, automotive interior materials, and elastic fibers due to their unique elasticity.

[0004] Furthermore, unlike non-recyclable rubber materials, the demand for this elastomer has increased significantly due to its ease of recycling. In particular, thermoplastic polyester copolymers are used as fibrous aggregate materials due to their excellent elasticity.

[0005] Thermoplastic elastomers (TPEs) are polymers that simultaneously possess two distinct properties: thermoplasticity, allowing them to be reshaped upon heating, and elasticity, characteristic of rubber-like polymers. TPEs are block copolymers, typically composed of hard segments exhibiting thermoplastic characteristics and soft segments exhibiting elasticity, thus simultaneously displaying two different properties.

[0006] This type of thermoplastic elastomer is manufactured by copolymerizing acidic components such as terephthalic acid, dimethyl terephthalate, isophthalic acid, and dimethyl isophthalate with glycol components such as poly(tetramethylene ether) glycol, butanediol, polyethylene glycol, and ethylene glycol. However, the manufacture of low-melting-point thermoplastic elastomers using this polymerization method presents challenges, including the need for equipment for storing and handling butanediol, and equipment for recovering byproducts such as tetrahydrofuran. In particular, tetrahydrofuran is a highly hazardous substance with toxicity and explosiveness, posing significant difficulties in its safety management.

[0007] In addition, although there is a strong demand trend for this thermoplastic elastomer, the market size is relatively small, and the production of polymers through polymerization methods has the disadvantage of increased fixed costs, which leads to higher overall costs.

[0008] [Prior Technology Documents]

[0009] [Patent Literature]

[0010] Korean Patent Application Publication No. 10-2016-0014627 (Publication Date: February 11, 2016) Summary of the Invention

[0011] The technical problem that the invention aims to solve

[0012] The present invention is proposed to solve the above-mentioned problems, and aims to provide a nonwoven fabric that not only has excellent mechanical strength and resilience, but also exhibits excellent recovery force with a significantly low permanent compression set, as well as mattresses and top covers containing the same.

[0013] Means for solving technical problems

[0014] To address the aforementioned problems, the thermally bondable composite fiber of the present invention may contain TPEE (Thermoplastic Polyether-ester Elastomer).

[0015] In a preferred embodiment of the present invention, the thermally bonded composite fiber of the present invention, based on the component analysis results of nuclear magnetic resonance (NMR) spectroscopy, may contain acid components and glycol components. The acid components, relative to the total mol% of the acid components, may contain 27-33 mol% isophthalic acid, and the glycol components, relative to the total mol% of the glycol components, may contain 6-9 mol% diethylene glycol, 20-23 mol% 1,4-butanediol, and 6-9 mol% poly(tetramethylene glycol).

[0016] In a preferred embodiment of the present invention, the weight average molecular weight of poly(tetramethylene glycol) can be 900 to 1100.

[0017] In a preferred embodiment of the present invention, the melting point of TPEE can be 130-140°C.

[0018] In a preferred embodiment of the present invention, the MI (melt index) of TPEE can be 30 to 70 g / min.

[0019] In a preferred embodiment of the present invention, the crystallization temperature of TPEE can be 45–55°C.

[0020] In a preferred embodiment of the present invention, the TPEE can simultaneously satisfy the following conditions (1) and (2):

[0021] (1) 2.0 ≤ A / B ≤ 2.4

[0022] In condition (1), A represents the weight-average molecular weight (Mw) of TPEE, and B represents the number-average molecular weight (Mn) of TPEE.

[0023] (2) 1.5 ≤ C / A ≤ 1.8

[0024] In condition (2), A represents the weight-average molecular weight (Mw) of TPEE, and C represents the Z-average molecular weight (Mz) of TPEE.

[0025] In a preferred embodiment of the present invention, the weight average molecular weight (Mw) of TPEE can be 70,000 to 75,000.

[0026] In a preferred embodiment of the present invention, the number average molecular weight (Mn) of TPEE can be 30,000 to 35,000.

[0027] In a preferred embodiment of the present invention, the Z-average molecular weight (Mz) of TPEE can be 100,000 to 130,000.

[0028] On the other hand, the thermo-adhesive composite fiber of the present invention is manufactured by composite spinning of a first component and a second component. The first component includes a first polyester resin, and the second component includes a second polyester resin and TPEE (Thermoplastic Polyether-ester Elastomer). According to the component analysis results of nuclear magnetic resonance (NMR) spectroscopy, the thermo-adhesive composite fiber of the present invention contains acid components and glycol components. The acid component, relative to the total mole percentage of the acid component, contains 27 to 33 mol% of isophthalic acid. The glycol component, relative to the total mole percentage of the glycol component, may contain 6 to 9 mol% of diethylene glycol, 20 to 23 mol% of 1,4-butanediol, and 6 to 9 mol% of poly(tetramethylene glycol).

[0029] In a preferred embodiment of the present invention, the second component may comprise 45 to 65% by weight of a second polyester resin and 35 to 55% by weight of TPEE relative to the total weight.

[0030] In a preferred embodiment of the present invention, the first polyester resin may be a PET (polyethylene terephthalate) resin with an intrinsic viscosity (IV) of 0.55 to 0.75 dL / g.

[0031] In a preferred embodiment of the present invention, the second polyester resin may be a copolyester resin with an intrinsic viscosity (IV) of 0.51 to 0.71 dL / g.

[0032] In a preferred embodiment of the present invention, the copolyester resin is manufactured by polycondensation reaction of a copolyester resin composition, the copolyester resin composition comprising: an ester compound manufactured by esterification reaction of an acid component comprising terephthalic acid and isophthalic acid with a diol component comprising ethylene glycol and diethylene glycol; and poly(tetramethylene glycol), which may comprise 1 to 10 parts by weight of poly(tetramethylene glycol) relative to 100 parts by weight of the ester compound.

[0033] In a preferred embodiment of the present invention, the cross-sectional shape of the thermally bonded composite fiber of the present invention can be core-sheath shaped, peanut-shaped side by side, or circular side by side.

[0034] Furthermore, the thermally bondable core-sheath composite fiber of the present invention may include a core comprising a first polyester resin; and a sheath configured to surround the core and comprising a second polyester resin and TPEE (Thermoplastic Polyether-ester Elastomer).

[0035] In a preferred embodiment of the present invention, the thermally bonded core-sheath composite fiber of the present invention, based on the component analysis results of nuclear magnetic resonance (NMR) spectroscopy, contains acid components and glycol components. The acid components, relative to the total mol% of the acid components, contain 27-33 mol% isophthalic acid. The glycol components, relative to the total mol% of the glycol components, may contain 6-9 mol% diethylene glycol, 20-23 mol% 1,4-butanediol, and 6-9 mol% poly(tetramethylene glycol).

[0036] In a preferred embodiment of the present invention, the cross-sectional area ratio of the core and the sheath can be 1 to 2:1.

[0037] In a preferred embodiment of the present invention, the fineness of the thermally bonded core-sheath composite fiber of the present invention can be 2.0 to 10.0 denier, and the fiber length can be 44 to 84 mm.

[0038] On the other hand, the nonwoven fabric of the present invention can be the thermally bonded composite fiber of the present invention, or a nonwoven fiber web containing the thermally bonded composite fiber of the present invention, which is manufactured by heat treatment at a temperature of 150 to 180°C.

[0039] In a preferred embodiment of the present invention, the nonwoven fabric of the present invention may be formed with a TPEE matrix.

[0040] In a preferred embodiment of the present invention, the permanent compression set of the nonwoven fabric of the present invention, measured by the ASTM D3574 TEST D method, can be 22-33%.

[0041] In a preferred embodiment of the present invention, the resilience of the nonwoven fabric of the present invention, measured by the ASTM D3574 TEST H method, can be 40-65%.

[0042] In a preferred embodiment of the present invention, the nonwoven fabric of the present invention may have a basis weight of 850-1250 gsm and a thickness of 30-70 mm.

[0043] Furthermore, the mattress of the present invention comprises the nonwoven fabric of the present invention.

[0044] On the other hand, the top pad of the present invention comprises the nonwoven fabric of the present invention.

[0045] The terminology used in this invention will be explained below.

[0046] In this invention, the term "fiber" as used refers to "yarn" or "thread," and refers to various conventional types of yarn and fiber.

[0047] In this invention, the term "composite fiber" as used refers to the filament itself produced by composite spinning, or to fibers that have been stretched and / or partially stretched.

[0048] Invention Effects

[0049] The thermally bonded composite fiber, the nonwoven fabric containing it, the mattress and top cover containing it of the present invention not only have excellent resilience, but also excellent mechanical strength.

[0050] In particular, the thermally bonded composite fiber of the present invention, the nonwoven fabric containing it, the mattress and the top cover containing it exhibit excellent resilience due to their significantly low compression set. Attached Figure Description

[0051] Figure 1 A diagram illustrating the TPEE matrix formed in the nonwoven fabric of the present invention according to a preferred embodiment.

[0052] Figure 2 To obtain SEM images of the thermally bonded core-sheath composite fibers manufactured in Example 1 using a scanning electron microscope. Detailed Implementation

[0053] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, so that those skilled in the art can readily implement the invention. The present invention may be embodied in different forms and is not limited to the embodiments set forth herein. In the drawings, parts unrelated to the description have been omitted for clarity, and throughout the specification, the same or similar structural elements are given the same reference numerals.

[0054] The invented thermo-adhesive composite fiber may contain TPEE (Thermoplastic Polyether-ester Elastomer).

[0055] Specifically, TPEE can have a melting point of 130 to 140°C, preferably 131 to 139°C, and more preferably 132 to 136°C. If the melting point is below 130°C, there may be problems with poor spinning when manufacturing thermally bonded composite fibers. If the melting point exceeds 140°C, it may be impossible to manufacture the target nonwoven fabric.

[0056] Furthermore, the melt index (MI) of TPEE can be 30-70 g / min, preferably 31-50 g / min, and more preferably 35-45 g / min. If the MI is lower than 30 g / min, there may be a problem that the TPEE matrix cannot be formed when using the thermally bondable composite fiber of the present invention to manufacture nonwoven fabric. If the MI exceeds 50 g / min, there may be a problem that the physical properties of the nonwoven fabric are reduced.

[0057] In addition, the crystallization temperature of TPEE can be 45 to 55°C, preferably 46 to 54°C, and more preferably 48 to 52°C. If the crystallization temperature is lower than 45°C, fiber bonding may occur at room temperature (about 25°C). If it exceeds 55°C, elasticity may be reduced.

[0058] In addition, TPEE can satisfy both of the following conditions (1) and (2).

[0059] (1) 2.0≤A / B≤2.4, preferably 2.05≤A / B≤2.35, and more preferably 2.2≤A / B≤2.3.

[0060] (2) 1.5≤C / A≤1.8, preferably 1.55≤C / A≤1.75, and more preferably 1.55≤C / A≤1.65.

[0061] In conditions (1) and (2), A represents the weight-average molecular weight (Mw) of TPEE, B represents the number-average molecular weight (Mn) of TPEE, and C represents the Z-average molecular weight (Mz) of TPEE.

[0062] In condition (1), if A / B is less than 2.0, there may be a problem of reduced elasticity; if it exceeds 2.4, there may be a problem of poor spinnability when manufacturing the thermally bonded composite fiber of the present invention.

[0063] Furthermore, in condition (2), if C / A is less than 1.5, there may be a problem of reduced elasticity; if it exceeds 1.8, there may be a problem of poor spinnability when manufacturing the thermally bonded composite fiber of the present invention.

[0064] Furthermore, the weight-average molecular weight (Mw) of TPEE can be 70,000 to 75,000, preferably 70,500 to 74,500, and more preferably 71,500 to 73,500. If the weight-average molecular weight (Mw) is lower than 70,000, there may be a problem that the spinning of the thermo-bonded composite fiber of the present invention cannot be carried out due to the low viscosity. If it exceeds 75,000, there may be a problem of poor spinnability when manufacturing the thermo-bonded composite fiber of the present invention.

[0065] Furthermore, the number average molecular weight (Mn) of TPEE can be 30,000 to 35,000, preferably 30,500 to 34,500, and more preferably 31,500 to 33,500. If the number average molecular weight (Mn) is lower than 30,000, there may be a problem that the spinning of the thermo-bonded composite fiber of the present invention cannot be carried out due to the low viscosity. If it exceeds 35,000, there may be a problem of poor spinnability when manufacturing the thermo-bonded composite fiber of the present invention.

[0066] Furthermore, the Z-average molecular weight (Mz) of TPEE can be between 100,000 and 130,000, preferably between 110,000 and 125,000, and more preferably between 113,000 and 120,000. If the Z-average molecular weight (Mz) is lower than 100,000, there may be a problem that the spinning of the thermo-bonded composite fiber of the present invention cannot be carried out due to the low viscosity. If it exceeds 130,000, there may be a problem of poor spinnability when manufacturing the thermo-bonded composite fiber of the present invention.

[0067] On the other hand, the thermally bonded composite fiber of the present invention, based on the component analysis results of nuclear magnetic resonance (NMR) spectroscopy, can contain acid components and glycol components. Specifically, the acid component, relative to the total mole percentage of the acid components, can contain 27-33 mol% isophthalic acid, preferably 28-32 mol%, more preferably 29-31 mol%. Furthermore, the acid component, relative to the total mole percentage of the acid components, can contain 67-73 mol% terephthalic acid, preferably 68-72 mol%, more preferably 69-71 mol%. Furthermore, the glycol component, relative to the total mole percentage of the glycol components, can contain 6-9 mol% diethylene glycol, preferably 7-8.9 mol%, more preferably 8.0-8.8 mol%. Furthermore, the glycol component, relative to the total mole percentage of the glycol components, can contain 20-23 mol% 1,4-butanediol, preferably 20.5-22 mol%, more preferably 20.8-21.5 mol%. Furthermore, the glycol component, relative to the total mol% of the glycol component, may contain 6 to 9 mol% of poly(tetramethylene glycol), preferably 6 to 8 mol%, more preferably 6 to 7 mol%. Additionally, the glycol component, relative to the total mol% of the glycol component, may contain 54 to 74 mol% ethylene glycol, preferably 59 to 69 mol%, more preferably 62 to 66 mol%.

[0068] In addition, the weight average molecular weight of poly(tetramethylene glycol) can be 900 to 1100, preferably 950 to 1050. If the weight average molecular weight is lower than 900, there may be problems with the degree of polymerization and hardness. If it exceeds 1100, not only may there be problems with the degree of polymerization, but there may also be problems with reduced economic efficiency.

[0069] Furthermore, the thermally adhesive composite fiber of the present invention can be manufactured by composite spinning of the first component and the second component.

[0070] At this point, the first component may contain a first polyester resin, and the second component may contain a second polyester resin and TPEE (Thermoplastic Polyether-ester Elastomer), wherein the TPEE is as described above.

[0071] In addition, the first polyester resin can be a PET (polyethylene terephthalate) resin with an intrinsic viscosity (IV) of 0.55 to 0.75 dL / g, preferably 0.60 to 0.70 dL / g.

[0072] In addition, the second polyester resin can be a copolyester resin with an intrinsic viscosity (IV) of 0.51 to 0.71 dL / g, preferably 0.56 to 0.66 dL / g.

[0073] On the other hand, the copolyester resin can be manufactured by polycondensation reaction of the copolyester resin composition. Specifically, the polyester resin composition may contain an ester compound and poly(tetramethylene glycol), and relative to 100 parts by weight of the ester compound, it may contain 1 to 10 parts by weight of poly(tetramethylene glycol) with a weight average molecular weight of 900 to 1100, preferably 950 to 1050, preferably 3 to 7 parts by weight. Furthermore, the ester compound can be manufactured by esterification reaction of an acid component containing terephthalic acid and isophthalic acid with a diol component containing ethylene glycol and diethylene glycol. Specifically, the acid component relative to the total mol% of the acid component may include 65-85 mol% of terephthalic acid, preferably 70-80 mol%, and 25-45 mol% of isophthalic acid, preferably 30-40 mol%. The glycol component relative to the total mol% of the glycol component may include 85-95 mol% of ethylene glycol, preferably 88-92 mol%, and 5-15 mol% of diethylene glycol, preferably 8-12 mol%.

[0074] Furthermore, the second component, relative to the total weight%, may contain 45-65% by weight of a second polyester resin, preferably 50-60% by weight, and 35-55% by weight of TPEE, preferably 40-50% by weight. If the TPEE content is less than 35% by weight, there may be a problem that the adhesiveness of the thermally bondable composite fiber of the present invention is low, thus making it impossible to manufacture the target nonwoven fabric. If it exceeds 55% by weight, there may be an economic problem.

[0075] On the other hand, the cross-sectional shape of the thermally adhesive composite fiber of the present invention can be core-sheath shaped, peanut-shaped side by side, or circular side by side.

[0076] Furthermore, the thermally bondable core-sheath composite fiber of the present invention may comprise a core comprising a first polyester resin, and a sheath configured to surround the core and comprising a second polyester resin and TPEE (Thermoplastic Polyether-ester Elastomer). In this case, the first polyester resin, the second polyester resin, and the TPEE are as described above. Additionally, the sheath may comprise 45–65% by weight of the second polyester resin, preferably 50–60% by weight, and 35–55% by weight of TPEE, preferably 40–50% by weight, relative to the total weight percentage.

[0077] Furthermore, based on the component analysis results obtained by nuclear magnetic resonance (NMR) spectroscopy, the thermally bonded core-sheath composite fiber of the present invention may contain acid components and glycol components. Specifically, the acid component, relative to the total mol% of the acid components, may contain 27-33 mol% isophthalic acid, preferably 28-32 mol%, more preferably 29-31 mol%. Furthermore, the acid component, relative to the total mol% of the acid components, may contain 67-73 mol% terephthalic acid, preferably 68-72 mol%, more preferably 69-71 mol%. Furthermore, the glycol component, relative to the total mol% of the glycol components, may contain 6-9 mol% diethylene glycol, preferably 7-8.9 mol%, more preferably 8.0-8.8 mol%. Furthermore, the glycol component, relative to the total mol% of the glycol components, may contain 20-23 mol% 1,4-butanediol, preferably 20.5-22 mol%, more preferably 20.8-21.5 mol%. Furthermore, the glycol component, relative to the total mole percentage of the glycol component, may contain 6 to 9 mol% poly(tetramethylene glycol), preferably 6 to 8 mol%, more preferably 6 to 7 mol%. Additionally, the glycol component, relative to the total mole percentage of the glycol component, may contain 54 to 74 mol% ethylene glycol, preferably 59 to 69 mol%, more preferably 62 to 66 mol%. Furthermore, the weight average molecular weight of the poly(tetramethylene glycol) may be 900 to 1100, preferably 950 to 1050. If the weight average molecular weight is below 900, there may be problems with the degree of polymerization and hardness; if it exceeds 1100, not only may there be problems with the degree of polymerization, but there may also be problems with reduced economic efficiency.

[0078] Furthermore, the cross-sectional area ratio of the core to the sheath of the thermally bonded core-sheath composite fiber of the present invention can be 1 to 2:1, preferably 1.3 to 1.7:1. If it is lower than 1:1, there may be elasticity problems; if it exceeds 2:1, there may be problems in manufacturing the fiber.

[0079] Furthermore, the fineness of the thermally bonded core-sheath composite fiber of the present invention can be 2.0 to 10.0 denier, preferably 4.0 to 8.0 denier.

[0080] Furthermore, the fiber length of the thermally adhesive core-sheath composite fiber of the present invention can be 44 to 84 mm, preferably 54 to 74 mm.

[0081] On the other hand, the thermally bonded core-sheath composite fiber of the present invention can be manufactured by melt spinning.

[0082] Specifically, the method for manufacturing the thermally adhesive core-sheath composite fiber of the present invention may include steps one through five.

[0083] First, as the first step of the method for manufacturing thermally bonded core-sheath composite fibers of the present invention, core-forming resin and sheath-forming resin can be fed into a composite spinneret and composite spinning can be performed to manufacture unstretched sub-tows.

[0084] At this point, composite spinning can be carried out using spinnerets of various shapes. Depending on the shape of the spinneret, the resulting bundle is preferably a core-sheath monofilament produced by a core-sheath monofilament produced by a core-sheath monofilament. In this case, the core of the core-sheath monofilament may contain a core-forming resin, and the sheath may contain a sheath-forming resin. Furthermore, the core-forming resin may contain a first polyester resin, and the sheath-forming resin may contain a second polyester resin and TPEE (Thermoplastic Polyether-ester Elastomer).

[0085] Next, as a second step in the method for manufacturing thermally bonded core-sheath composite fibers of the present invention, the unstretched sub-tow can be stretched, dried, and heat-set.

[0086] At this point, the stretching can be performed on the unstretched sub-tow at a temperature of 20–90°C at a stretch ratio of 2.0–6.0 times, preferably 3.0–5.0 times c. If the stretch ratio is less than 2.0 times, the increased elongation may lead to a decrease in the physical properties of the product utilizing the thermally bonded core-sheath composite fiber of this invention. If the stretch ratio exceeds 6.0 times, fiber breakage may occur.

[0087] Furthermore, drying and heat setting can be carried out at a temperature of 50–120°C, preferably at a temperature of 70–115°C. The drying and heat setting time can be 1–60 minutes, preferably 3–50 minutes, and various curled shapes can be achieved through heat setting.

[0088] Next, as a third step in the method for manufacturing thermally bonded core-sheath composite fibers of the present invention, the stretched and dried sub-tows can be impregnated in a hydrophilic emulsion to coat their surfaces.

[0089] At this time, any hydrophilic emulsion can be used as long as it is a hydrophilic emulsion that is commonly used in this technical field, and preferably it may contain one or more selected from ionic surfactants, nonionic surfactants, anionic surfactants and amphoteric surfactants.

[0090] Next, as a fourth step in the method for manufacturing the thermally bondable core-sheath composite fiber of the present invention, a crimp can be imparted to the sub-bundles coated on their surface. The crimp can be performed using general crimping methods available in the art.

[0091] Finally, as the fifth step in the method for manufacturing the thermally bonded core-sheath composite fiber of the present invention, the coiled sub-bundle can be cut to manufacture the thermally bonded composite fiber.

[0092] At this point, cutting is a process of cutting the heat-set sub-bundles of the thermally bonded core-sheath composite fiber of the present invention to obtain an appropriate fiber length, based on the processed product to which the thermally bonded core-sheath composite fiber of the present invention is intended to be used. It can be performed using general cutting methods that are available in the art.

[0093] On the other hand, the nonwoven fabric of the present invention can be a nonwoven fiber web comprising the thermally bondable composite fiber of the present invention or the thermally bondable core-sheath composite fiber of the present invention, manufactured by heat treatment at a temperature of 150-180°C, preferably 160-170°C, and more preferably 160-165°C. If the heat treatment temperature is below 150°C, the adhesiveness of the nonwoven fiber web may decrease, resulting in the inability to manufacture the target nonwoven fabric. If the temperature exceeds 180°C, the physical properties of the manufactured nonwoven fabric may decrease.

[0094] Furthermore, the nonwoven fiber web can be manufactured by carding the thermally bonded composite fiber of the present invention or the thermally bonded core-sheath composite fiber of the present invention.

[0095] Furthermore, the nonwoven fabric of the present invention can be formed with a TPEE matrix. Specifically, see [link to documentation]. Figure 1 The nonwoven fabric of the present invention is composed of a mixture of polyester resin 10 and TPEE 20. When the two materials with different components are mixed, one component has a domain morphology, and the other component has a matrix morphology. The nonwoven fabric of the present invention has a structure in which polyester resin 10 forms the domain and TPEE 20 forms the matrix. As described above, since a TPEE matrix is ​​formed in the nonwoven fabric of the present invention, the nonwoven fabric of the present invention has properties close to those of TPEE.

[0096] Furthermore, the Shore D hardness of the nonwoven fabric of the present invention can be below 55HS, preferably 30 to 70HS, and more preferably 31 to 60HS.

[0097] Furthermore, the nonwoven fabric of the present invention has a compression stiffness of 2.1 to 3.3 N, preferably 2.7 to 3.1 N, as measured by the ASTM D3574 TEST D method. If the compression stiffness is lower than 2.1 N, there may be a lack of elasticity; if it exceeds 3.3 N, there may be a problem of hardening.

[0098] Furthermore, the permanent compression set of the nonwoven fabric of the present invention, measured by the ASTM D3574 TEST D method, can be 22-33%, preferably 24-32%, and more preferably 27-31%. If the permanent compression set is less than 22%, there may be a problem that the nonwoven fabric feels stiff due to its good elasticity; if it exceeds 33%, there may be a problem that the nonwoven fabric collapses due to insufficient elasticity.

[0099] Furthermore, the resilience of the nonwoven fabric of the present invention, measured by the ASTM D3574 TEST H method, can be 40-65%, preferably 50-60%. If the resilience is less than 40%, the nonwoven fabric may be too soft; if it exceeds 65%, the nonwoven fabric may become stiff.

[0100] Furthermore, the basis weight of the nonwoven fabric of the present invention can be 850-1250 gsm, preferably 950-1150 gsm.

[0101] Furthermore, the thickness of the nonwoven fabric of the present invention can be 30-70 mm, preferably 40-60 mm.

[0102] On the other hand, the nonwoven fabric of the present invention can be manufactured by air-through bonding or calendering of the thermally bonded composite fiber or the thermally bonded core-sheath composite fiber of the present invention.

[0103] As an example, the method for manufacturing the nonwoven fabric of the present invention includes: a first step of carding the thermally bonded composite fiber or the thermally bonded core-sheath composite fiber of the present invention to manufacture a nonwoven fiber web; and a second step of heat-treating the nonwoven fiber web to manufacture a nonwoven fabric.

[0104] At this point, heat treatment can be carried out using a hot air blower. The heat treatment can be performed at a temperature of 150–180°C, preferably 160–170°C, more preferably 160–165°C, for 1 second to 10 minutes, and more preferably 2 seconds to 5 minutes. If the heat treatment temperature is below 150°C, the physical properties of the nonwoven fabric may decrease; if the heat treatment temperature exceeds 180°C, the bonding of the nonwoven fabric may become difficult.

[0105] On the other hand, the mattress of the present invention may include the nonwoven fabric of the present invention.

[0106] Furthermore, the top pad of the present invention may comprise the nonwoven fabric of the present invention.

[0107] The present invention has been described above with reference to embodiments, but these are merely examples and do not limit the embodiments of the present invention. Those skilled in the art should understand that various modifications and applications not illustrated above can be made without departing from the essential characteristics of the present invention. For example, the constituent elements specifically shown in the embodiments of the present invention can be implemented in variations. Furthermore, these differences related to such modifications and applications should be interpreted as being included within the scope of the present invention as defined in the appended claims.

[0108] Preparation Example 1: Preparation of TPEE (Thermoplastic Polyether Elastomer) Chips

[0109] A TPEE chip with the physical properties described in Table 1 below was prepared.

[0110] [Table 1]

[0111]

[0112] Preparation Example 2: Manufacturing of Copolyester Resin Chips

[0113] (1) The acid component and the diol component were added at a molar ratio of 1:1.6, and the mixture was mixed and esterified at a temperature of 250°C and a pressure of 1140 torr to prepare an ester compound with a preparation rate of 97.5%.

[0114] At this point, as the acid component, 75 mol% of terephthalic acid and 35 mol% of isophthalic acid were used relative to the total mole percentage of the acid component, and as the glycol component, 90 mol% of ethylene glycol and 10 mol% of diethylene glycol were used relative to the total mole percentage of the glycol component.

[0115] (2) For 100 parts by weight of the prepared ester compound, 5 parts by weight of poly(tetramethylene glycol) with a weight average molecular weight of 1000 and 0.03 parts by weight of antimony trioxide (condensation catalyst) were added. While the final pressure was slowly reduced to 0.5 torr, the temperature was raised to 280°C to carry out the mixing and condensation reaction, and a copolyester resin with an intrinsic viscosity (IV) of 0.61 dL / g was prepared. The copolyester resin was then sliced ​​to prepare copolyester resin chips.

[0116] Preparation Example 3: Preparation of TPEE Mixed Resin

[0117] The TPEE chips prepared in Preparation Example 1 and the copolyester resin chips prepared in Preparation Example 2 were melt-mixed at 180°C to prepare a molten mixture. A compatibilizer was then mixed into the molten mixture to prepare a TPEE blend resin. Alternatively, 45% by weight of the TPEE chips prepared in Preparation Example 1 and 55% by weight of the copolyester resin chips prepared in Preparation Example 2 were mixed to prepare a molten mixture. Then, 95% by weight of the molten mixture and 5% by weight of the compatibilizer were mixed to prepare a TPEE blend resin. An epoxy-based compatibilizer was used as the compatibilizer.

[0118] Example 1: Preparation of thermo-bonded core-sheath composite fibers

[0119] (1) As the core forming resin, PET (polyethylene terephthalate) resin with an intrinsic viscosity (IV) of 0.65 dL / g was used. As the sheath forming resin, TPEE mixed resin prepared in Preparation Example 3 was used. The resin was fed into the core-sheath composite spinneret for composite spinning to prepare a core-sheath unstretched sub-bundle with a circular cross-section of the core and sheath.

[0120] (2) The prepared core-sheath unstretched sub-bundle was stretched by 4.0 times at 80°C and then dried and heat-set at 90°C for 10 minutes.

[0121] (3) The stretched and dried sub-bundles are immersed in a hydrophilic emulsion to coat their surfaces.

[0122] (4) Use a crimper to crimp the coated sub-bundles.

[0123] (5) The curled sub-bundles are cut to prepare a heat-bonded core-sheath composite fiber with a fineness of 6.0 denier and a fiber length of 64 mm. At this time, the cross-sectional area ratio of the core to the sheath is 3:2. The core is made of PET resin and the sheath is made of the TPEE mixed resin prepared in Preparation Example 3.

[0124] Comparative Example 1: Preparation of Thermo-Adhesive Core-Sheath Composite Fibers

[0125] The thermally bonded core-sheath composite fiber was prepared using the same method as in Example 1. However, unlike Example 1, the copolyester resin prepared in Preparation Example 2 was used for sheath formation instead of the TPEE mixed resin prepared in Preparation Example 3, and the thermally bonded core-sheath composite fiber was finally prepared.

[0126] Experimental Example 1: Composition Analysis

[0127] Nuclear magnetic resonance (NMR) spectroscopy was performed on the thermally bonded core-sheath composite fibers prepared in Example 1 and Comparative Example 1 to analyze the composition and content of each thermally bonded core-sheath composite fiber prepared in Example 1 and Comparative Example 1. The results are shown in Table 2 below.

[0128] [Table 2]

[0129]

[0130]

[0131] Experimental Example 2: Determination of Thermal Adhesion Strength

[0132] In a polytetrafluoroethylene-coated frame measuring 30cm × 30cm × 1cm, the thermally bonded core-sheath composite fibers prepared in Example 1 and Comparative Example 1 were placed into the frame, respectively. The fibers were then carded to form nonwoven webs, which were then heat-treated at 160°C for 10 minutes. The heat-treated nonwoven webs were cut into 10cm × 2cm lengths. The thermal bonding strength of the cut nonwoven webs was measured using an INSTRON universal testing machine, and the results are shown in Table 3 below.

[0133] [Table 3]

[0134] distinguish Example 1 Comparative Example 1 Thermal bond strength (N) 125 125

[0135] As shown in Table 3, it can be confirmed that the thermally bonded core-sheath composite fiber prepared in Example 1 exhibits a comparable level of thermal bonding strength to the thermally bonded core-sheath composite fiber prepared in Comparative Example 1.

[0136] Experiment Example 3: SEM Photography

[0137] The thermally bonded core-sheath composite fiber prepared in Example 1 was photographed using a scanning electron microscope, and its SEM image is shown below. Figure 2 In the middle. For example Figure 2 As shown, it can be confirmed that the TPEE mixed resin forming the sheath in Preparation Example 3 forms a TPEE matrix.

[0138] Preparation Example 1 and Comparative Preparation Example 1: Preparation of Nonwoven Fabrics

[0139] The thermally bonded core-sheath composite fibers prepared in Example 1 and Comparative Example 1 were carded to prepare nonwoven fiber webs. The prepared nonwoven fiber webs were heat-treated at 160°C for 20 seconds using a circulating hot air blower to produce a nonwoven fabric with a basis weight of 1050 gsm and a thickness of 50 mm.

[0140] Experiment Example 4: Compression Hardness Measurement

[0141] The compression hardness of the nonwoven fabrics prepared in Preparation Example 1 and Comparative Preparation Example 1 was determined using the KS M ISO 3386-1 method, and the results are shown in Table 4 below.

[0142] Experimental Example 5: Determination of Long-Term Compression Deformation Rate

[0143] The permanent compression set of the nonwoven fabrics prepared in Preparation Example 1 and Comparative Preparation Example 1 was determined using the ASTM D3574 (Flexible Cellular Materials - Slab, Bonded, and Molded Unrethane Foams) TEST D method. The results are shown in Table 4 below. Permanent compression set refers to the rate of deformation that cannot be recovered over time. A higher permanent compression set indicates a worse recovery force.

[0144] Experimental Example 6: Resilience Measurement

[0145] The resilience of the nonwoven fabrics prepared in Preparation Example 1 and Comparative Preparation Example 1 was determined using the ASTM D3574 (Flexible cellular Materials - Slab, Bonded, and Molded Unrethane Foams) TEST H method, and the results are shown in Table 4 below.

[0146] Experimental Example 7: Shore D Hardness Measurement

[0147] The Shore D hardness of each nonwoven fabric prepared in Preparation Example 1 and Comparative Preparation Example 1 was determined using a Shore hardness tester, and the results are shown in Table 4 below.

[0148] [Table 4]

[0149]

[0150]

[0151] As shown in Table 4, it can be confirmed that the nonwoven fabric prepared in Preparation Example 1 has the same resilience as the nonwoven fabric prepared in Comparative Preparation Example 1, and the mechanical strength (compression hardness, Shore D hardness, etc.) is at the same level, but the permanent compression deformation rate is significantly lower, showing excellent recovery force.

[0152] Simple variations or modifications of the present invention can be readily implemented by those skilled in the art, and such variations or modifications can be considered to be included within the scope of the present invention.

Claims

1. A thermo-adhesive composite fiber comprising TPEE, characterized in that, The thermally bonded composite fiber, based on component analysis using nuclear magnetic resonance spectroscopy, contains acidic and diol components. The acid component, relative to the total mol% of the acid components, comprises 27–33 mol% isophthalic acid. The diol component, relative to the total molar percentage of the diol component, comprises 6-9 mol% diethylene glycol, 20-23 mol% 1,4-butanediol, and 6-9 mol% polytetramethylene glycol.

2. The thermo-adhesive composite fiber according to claim 1, characterized in that, The polytetramethylene glycol has a weight average molecular weight of 900 to 1100.

3. The thermo-adhesive composite fiber according to claim 1, characterized in that, The melting point of the TPEE is 130–140°C.

4. The thermo-adhesive composite fiber according to claim 1, characterized in that, The melt flow index of the TPEE is 30–70 g / min.

5. The thermo-adhesive composite fiber according to claim 1, characterized in that, The crystallization temperature of the TPEE is 45–55°C.

6. The thermo-adhesive composite fiber according to claim 1, characterized in that, The TPEE simultaneously satisfies the following conditions (1) and (2): (1) 2.0 ≤ A / B ≤ 2.4, (2) 1.5 ≤ C / A ≤ 1.8; In the conditions (1) and (2), A represents the weight average molecular weight Mw of TPEE, B represents the number average molecular weight Mn of TPEE, and C represents the Z-average molecular weight Mz of TPEE.

7. The thermo-adhesive composite fiber according to claim 6, characterized in that, The weight-average molecular weight (Mw) of the TPEE is 70,000 to 75,000. The number-average molecular weight (Mn) of the TPEE is 30,000 to 35,000. The Z-average molecular weight Mz of the TPEE is 100,000 to 130,000.

8. A thermo-adhesive composite fiber manufactured by composite spinning of a first component and a second component, characterized in that, The first component comprises a first polyester resin. The second component comprises a second polyester resin and TPEE. The thermally bonded composite fiber, based on component analysis using nuclear magnetic resonance spectroscopy, contains acidic and diol components. The acid component, relative to the total mol% of the acid components, comprises 27–33 mol% isophthalic acid. The diol component, relative to the total molar percentage of the diol component, comprises 6-9 mol% diethylene glycol, 20-23 mol% 1,4-butanediol, and 6-9 mol% polytetramethylene glycol.

9. The thermo-adhesive composite fiber according to claim 8, characterized in that, The second component, relative to the total weight%, comprises 45-65% by weight of a second polyester resin and 35-55% by weight of TPEE.

10. The thermo-adhesive composite fiber according to claim 8, characterized in that, The first polyester resin is a PET resin with an intrinsic viscosity of 0.55–0.75 dL / g. The second polyester resin is a copolyester resin with an inherent viscosity of 0.51 to 0.71 dL / g.

11. The thermo-adhesive composite fiber according to claim 10, characterized in that, The copolyester resin is manufactured by polycondensation reaction of a copolyester resin composition. The copolyester resin composition comprises: an ester compound prepared by esterification of an acid component containing terephthalic acid and isophthalic acid with a diol component containing ethylene glycol and diethylene glycol; and polytetramethylene glycol. The ester compound comprises 1 to 10 parts by weight of polytetramethylene glycol, relative to 100 parts by weight.

12. The thermo-adhesive composite fiber according to claim 8, characterized in that, The cross-sectional shape of the thermally bonded composite fibers is core-sheath shaped, peanut-shaped side by side, or circular side by side.

13. A thermo-adhesive core-sheath composite fiber, characterized in that, include: The core comprises a first polyester resin; as well as A sheath portion, configured to surround the core portion, and comprising a second polyester resin and TPEE; The thermally bonded core-sheath composite fiber, according to the compositional analysis results of nuclear magnetic resonance spectroscopy, contains acidic and diol components. The acid component, relative to the total mol% of the acid components, comprises 27–33 mol% isophthalic acid. The diol component, relative to the total molar percentage of the diol component, comprises 6-9 mol% diethylene glycol, 20-23 mol% 1,4-butanediol, and 6-9 mol% polytetramethylene glycol.

14. The thermo-adhesive core-sheath composite fiber according to claim 13, characterized in that, The cross-sectional area ratio of the core and the sheath is 1 to 2:

1.

15. The thermo-adhesive core-sheath composite fiber according to claim 13, characterized in that, The thermally bonded core-sheath composite fiber has a fineness of 2.0 to 10.0 denier and a fiber length of 44 to 84 mm.

16. A nonwoven fabric, characterized in that, Nonwoven fabrics manufactured by heat-treating nonwoven fiber webs containing the thermally bondable composite fibers according to claim 1, claim 8, or claim 13 at a temperature of 150–180°C. The nonwoven fabric is formed with a TPEE matrix.

17. The nonwoven fabric according to claim 16, characterized in that, The permanent compressive strain rate, measured using ASTM D3574 TEST D method, is 22–33%. The resilience measured using the ASTM D3574 TEST H method is 40–65%.

18. The nonwoven fabric according to claim 16, characterized in that, The nonwoven fabric has a basis weight of 850–1250 gsm and a thickness of 30–70 mm.

19. A mattress, characterized in that, It includes the nonwoven fabric according to claim 16.

20. A top pad, characterized in that, It includes the nonwoven fabric according to claim 16.

Images