Multilayer laminated composite profile fiber

Abstract

The present invention provides a multilayer laminated composite fiber having a barrier property, sweat stain inhibition, UV cut-off property, soft hand feeling, inhibition of fluff generation, and excellent high-order passing property. The present invention relates to a multilayer laminated profile composite fiber which is a multilayer structure in which at least two or more components are laminated in parallel with the fiber surface in a fiber profile perpendicular to the fiber axis, 3 layers to 15 layers, the thickness of the outermost layer is 10 mass% to 40 mass% of inorganic particles relative to the entire fiber, and the single yarn fineness is 0.7 dtex to 3.5 dtex.

Description

TECHNICAL FIELD

[0001] The present application relates to a composite profile fiber in which at least two or more polymers are stacked in multiple layers in parallel with the surface of a fiber. BACKGROUND

[0002] Synthetic fibers containing polyester or polyamide, etc. have excellent mechanical properties or dimensional stability, and thus are widely used for clothing uses or industrial uses, etc. However, in recent years, people's lives have diversified, and more comfortable lives are pursued, and in many uses including clothing, fibers having superior functions that are not found in existing synthetic fibers are required. In particular, with global warming in recent years, in spring and summer clothing, clothing having excellent Ultra Violet cut and heat shielding properties, clothing in which sweat stains are not obvious even if sweating, and clothing that is not transparent even if thin are required.

[0003] As a method of imparting functions to synthetic fibers, sometimes a plurality of polymers having different compositions or properties are stacked in multiple layers. For example, in Patent Literature 1, a composite fiber having a light halo prevention effect and a scum suppression effect is described, in which a polymer containing a pigment having a low light reflectance is applied to an intermediate layer, and a polymer containing 0.3 wt% to 0.6 wt% of titanium oxide is applied to the outermost layer. In Patent Literature 2, a composite fiber having a luster or color development, ultraviolet / infrared reflection, etc. is described, in which an alternating stack structure of two or more polymers having different refractive indices is used to utilize the reflection of light between the layers or the interference of the reflected light. In Patent Literature 3, an electrically conductive fiber is described, in which the fiber profile is provided with a three-layer structure, and carbon black is contained in the intermediate layer to provide long-term excellent electrical properties.

[0004] PRIOR ART DOCUMENTS

[0005] PATENT LITERATURE

[0006] Patent Literature 1: Japanese Patent Laid-Open No. 2007-332504

[0007] Patent Literature 2: Japanese Patent Laid-Open No. 2017-115254

[0008] Patent Literature 3: Japanese Patent Laid-Open No. 2014-133950 SUMMARY

[0009] PROBLEMS TO BE SOLVED BY THE INVENTION

[0010] However, the three-layer structure fiber described in Patent Literature 1 has an effect of suppressing light halo in the screen gauze application, but in the case of being developed in the clothing application, the inorganic particle addition amount of the entire fiber or the inorganic particle addition amount of the polymer layer inside the outermost layer is small, and high penetration resistance is not exhibited. Therefore, sweat stain suppression, UV cutoff property, and thermal insulation property cannot be satisfied. In addition, in the case of being developed in the clothing application with a thick single yarn fineness, a soft hand feeling cannot be obtained. Furthermore, there is a problem that the viscosity of the pigment-containing polymer of the middle layer is higher than the viscosity of the polymer of the adjacent outermost layer, and thus the polymer flow stagnation in the composite die is easily caused by the aggregation of the inorganic particles, and the composite profile becomes abnormal. The multi-layer laminated composite fiber described in Patent Literature 2 has high aesthetic property and mechanical properties such as wear resistance, but the inorganic particle addition amount of the entire fiber or the inorganic particle addition amount of the polymer layer inside the outermost layer is small, and high penetration resistance is not exhibited. Therefore, sweat stain suppression, UV cutoff property, and thermal insulation property cannot be satisfied. The three-layer structure fiber described in Patent Literature 3 has a large amount of pigment in the middle layer, but the pigment is carbon black, and thus in the case of being developed in the clothing application, the penetration resistance, sweat stain suppression, and UV cutoff property are good, but are limited to black or dark gray, and there is a problem in thermal insulation property. In addition, in the case of being developed in the clothing application with a thick single yarn fineness, a soft hand feeling cannot be obtained.

[0011] The present application solves the existing problems, and provides a multi-layer laminated composite profile fiber having high penetration resistance and sweat stain suppression functionality. Furthermore, a multi-layer laminated composite profile fiber having sweat stain suppression, high penetration resistance, UV cutoff property, thermal insulation property, and soft hand feeling most suitable for spring and summer clothing applications is provided.

[0012] Technical means for solving the problem

[0013] The present application is achieved by the following means. That is,

[0014] (1) A multi-layer laminated composite profile fiber is a multi-layer structure in which at least two or more polymer components are laminated in 3 to 15 layers in parallel with the fiber surface in a fiber profile perpendicular to the fiber axis, the thickness of the outermost layer of the multi-layer structure is 0.1 to 1.0 μm, contains 5 to 40 mass% of inorganic particles with respect to the entire fiber, and the single yarn fineness is 0.7 to 3.5 dtex.

[0015] (2) The multi-layer laminated composite profile fiber according to the above (1), wherein 30 to 70 mass% of the inorganic particles are contained in at least one layer inside the fiber center side from the outermost layer.

[0016] ​(3) The multilayer laminated profiled fiber according to (1) or (2), wherein both of the two or more polymer components constituting the multilayer structure are polyesters or both are polyamides.

[0017] (4) The multilayer laminated profiled fiber according to (1) or (2), wherein the coefficient of variation (CV) % of the fiber profile area in the fiber profile perpendicular to the fiber axis is 10% or less.

[0018] Effects of the Invention

[0019] The multilayer laminated profiled fiber of the present invention can provide a cloth most suitable for spring and summer clothing use, having sweat stain suppression, high permeation resistance, UV cutoff, heat insulation, and a soft hand feeling. BRIEF DESCRIPTION OF DRAWINGS

[0020] [ Figure 1 ] is a schematic view of a composite die for explaining the production of the multilayer laminated profiled fiber of the present invention.

[0021] [ Figure 2 ] is a schematic view of a fiber profile for explaining the multilayer structure of the present invention. DETAILED DESCRIPTION

[0022] Hereinafter, embodiments of the present invention are described in detail.

[0023] Further, in the present specification, "mass %" is synonymous with "weight %".

[0024] The multilayer laminated profiled fiber of the present invention is a multilayer structure in which at least two or more polymer components are laminated in parallel with the fiber surface in 3 to 15 layers in the fiber profile perpendicular to the fiber axis, the thickness of the outermost layer of the multilayer structure is 0.1 to 1.0 μm, contains 5 to 40 mass % of inorganic particles with respect to the entire fiber, and the single yarn fineness is 0.7 to 3.5 dtex.

[0025] The multilayer structure laminated in the multilayer laminated profiled fiber of the present invention refers to a fiber having a multilayer structure from the fiber surface to the fiber center in the fiber profile perpendicular to the fiber axis, in which at least two or more polymer components are laminated in parallel in 3 or more layers to form a multilayer structure.

[0026] ​The number of layers of the multilayer laminated composite profile fiber of the present application is 3 to 15 layers. The more the number of layers of the multilayer structure, the higher the barrier property, but the effect saturates. From the viewpoint of yarn production, if the number of layers exceeds 15, abnormalities occur in profile formation, causing quality abnormalities. Therefore, from the viewpoint of the barrier property, UV cutoff property, heat shielding property, i.e., shielding performance, and basic performance and quality of the fiber, as the object of the present application, 3 to 9 layers are preferred, and further 3 to 5 layers are preferred.

[0027] The so-called sweat stain is a phenomenon in which a garment appears dark in color due to sweat, appearing like a stain. That is, if a cloth is wetted with water, surface reflection of sunlight decreases and transmission of light increases, causing a phenomenon in which the color appears dark. Sweat stains are significantly exhibited in light colors that are preferably developed in spring and summer garments, and therefore the demand for spring and summer garments in which sweat stains are not apparent is high. The present inventors and others have focused on the outermost layer of the multilayer structure, and found that by providing a thin layer at the outermost layer, it is possible to satisfy both sweat stain suppression and the barrier property, UV cutoff property, heat shielding property, i.e., shielding performance. Further, by focusing on at least one layer of the multilayer structure that is closer to the center of the fiber than the outermost layer, it is found that by forming a layer that has a high effect of absorbing and diffusely reflecting sunlight inside the outermost layer, it is possible to obtain a structure in which both sweat stain suppression and shielding performance are more excellent.

[0028] In the multilayer laminated composite profile fiber of the present application, the thickness of the outermost layer of the multilayer structure is By being in the range, excellent sweat stain suppression and the barrier property, UV cutoff property, heat shielding property, i.e., shielding performance are obtained. By reducing the thickness of the outermost layer, sweat stain suppression and the barrier property are improved, but if it is less than from the viewpoint of yarn production, abnormalities occur in profile formation, causing quality abnormalities. If the thickness of the outermost layer is more than , the sweat stain suppression effect is not exhibited. The preferred thickness of the outermost layer is .

[0029] Sunlight contains visible light, infrared rays, and ultraviolet rays, and it is desirable for spring and summer garments to have a function of not transmitting these and suppressing the temperature rise inside the garment (heat shielding property). Inorganic particles have an effect of absorbing and diffusely reflecting the sunlight, and by being kneaded into the fiber, it is possible to improve the barrier property, UV cutoff property (ultraviolet shielding), heat shielding property, i.e., shielding performance.

[0030] As the inorganic particles contained in the multilayer laminated composite profile fiber of the present application, inorganic particles having a substance refractive index of 2.0 or more are preferable. The higher the substance refractive index of the inorganic particles, the more excellent the effect of absorbing and diffusely reflecting sunlight. Preferred inorganic particles are titanium oxide (rutile type: 2.72), titanium oxide (anatase type: 2.52), zirconium oxide (2.20), and zinc oxide (2.01). The values in parentheses are substance refractive indices.

[0031] Among these, titanium oxide is more preferable in terms of the shielding property against sunlight and the ease of handling. The shielding property against sunlight refers to UV cutoff property that absorbs and shields ultraviolet rays harmful to the skin, heat shielding property that reflects visible and near-infrared regions of sunlight efficiently and suppresses the absorption of solar energy to suppress the temperature rise in clothes, and light blocking property that does not easily transmit light.

[0032] In the multilayer laminated composite profile fiber of the present application, 5 to 40 mass% of inorganic particles are contained with respect to the entire fiber. By setting to the range, excellent sweat stain suppression and light blocking, UV cutoff, and heat shielding properties, that is, shielding properties are obtained. If the content of inorganic particles is more than 40 mass%, the sweat stain suppression and light blocking, UV cutoff, and heat shielding properties, that is, the shielding properties are improved, but the effect is saturated, and the basic properties of the fiber such as strength are reduced. If the content of inorganic particles is less than 5 mass%, the sweat stain suppression and light blocking, UV cutoff, and heat shielding properties, that is, the shielding properties cannot be obtained. The content of inorganic particles is preferably 10 to 30 mass%.

[0033] In the multilayer laminated composite profile fiber of the present application, a thin layer is disposed in the outermost layer, and a layer having a high effect of absorbing and diffusely reflecting sunlight is disposed inside the outermost layer in at least one layer closer to the center of the fiber than the outermost layer. In at least one layer of the multilayer structure closer to the center of the fiber than the outermost layer, the content of inorganic particles is preferably 30 to 70 mass%. From the viewpoint of light blocking, UV cutoff, heat shielding, that is, shielding properties, or sweat stain suppression, it is preferable to be 30 mass% or more, and further preferably 40 mass% or more.

[0034] In addition, in the multilayer laminated composite profile fiber of the present application, the content of inorganic particles in the outermost layer of the multilayer structure is preferably 0.1 to 3.0 mass%. By setting the content of inorganic particles in the outermost layer to 0.1 mass% or more, from the viewpoint of yarn production and high-order processing, the friction with a fiber guide is reduced, and a pile suppressing effect is expected, which is preferable from the viewpoint of quality. Further, the content of inorganic particles in the outermost layer is preferably 2.0 mass% or less.

[0035] The single yarn fineness of the multilayer laminated complex profile fiber of the present application is 0.7 dtex to 3.5 dtex. In the case of clothing use, the hand is valued. In order to obtain the soft hand required for clothing use, the single yarn fineness is 3.5 dtex or less. For underwear, or shirt fabric, or down jacket lining, which directly contact the skin, the preferred single yarn fineness is 2.0 dtex or less. The smaller the single yarn fineness, the softer the hand, but if the single yarn fineness is less than 0.7 dtex, the profile formation of the layer containing inorganic particles becomes difficult.

[0036] The multilayer laminated complex profile fiber of the present application is preferably a long fiber, constituting a multifilament (a processed yarn contained therein). The preferred number of filaments in clothing use is 12 to 144, and the total fineness is 10 dtex to 200 dtex.

[0037] The finer the single yarn fineness, the more the number of filaments and the softer the hand that can be obtained. On the other hand, the finer the single yarn fineness, the lower the profile formation, and the larger the fiber profile deviation. Even if the profile formation is lowered, the barrier property, the UV cut-off property, the heat shielding property, that is, the shielding performance, which are the targets of the present application, can be obtained, but the basic performance, the quality of the fiber is lowered. Therefore, in the fiber profile perpendicular to the fiber axis direction, the fiber profile area CV% is preferably 10% or less.

[0038] Regarding the strength of the multifilament containing the multilayer laminated complex profile fiber of the present application, if it is an extended yarn (draw twist (DT)), it is 2.0 cN / dtex or more, if it is a semi-extended yarn (partially oriented yarn (POY)), it is 1.3 cN / dtex or more, and if it is a false twist processed yarn (draw textured yarn (DTY)), it is 2.0 cN / dtex or more.

[0039] Hereinafter, the manufacturing method of the multilayer laminated complex profile fiber of the present application will be described.

[0040] The two or more polymer components constituting the multilayer laminated complex profile fiber of the present application are not particularly limited as long as they are fiber-forming thermoplastic polymers. From the viewpoint of the inhibition of interlayer peeling in the multilayer structure of the fiber, and the formation of the complex profile, and the spinnability, it is preferred to use the same polymer. In the combination of the same polymer, as long as there are different compositions, for example, different viscosities, different contents of inorganic particles, etc. From the viewpoint of the processability, the two or more polymer components constituting the multilayer structure are preferably both polyester, or both polyamide. In addition, the sweat stain is a phenomenon exhibited when wetted with water, and therefore, it is preferred that the polymer type is one having a standard moisture regain of 5% or less, and more preferably, polyester.

[0041] Furthermore, given the significant environmental concerns, in this invention, from the viewpoint of reducing environmental impact, it is preferable to use plant-derived biopolymers or reusable polymers. The polymers used in this invention can be reusable polymers that have been recycled through any one of chemical recycling, material recycling, and thermal recycling.

[0042] As the polyester, polyethylene terephthalate (PET) with 80 mol% or more of the repeating units being polyethylene terephthalate, polybutylene terephthalate (PBT) with 80 mol% or more of the repeating units being butylene terephthalate, and polytrimethylene terephthalate (PTT) with 80 mol% or more of the repeating units being propylene glycol terephthalate are preferred. Furthermore, aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, naphthalene-2,6-dicarboxylic acid, phthalic acid, and sodium isophthalate 5-sulfonate, as well as aliphatic dicarboxylic acids such as adipic acid and sebacic acid, can be copolymerized as a third component to the extent that the fiber-forming properties of the homopolymer are impaired.

[0043] The polyamide can be any polyamide formed by repeated condensation of amide bonds, such as nylon 6, nylon 66, nylon 12, nylon 610, etc., or it can be a polyamide containing a small amount of a third component.

[0044] For preferred application in clothing, the multilayer laminated composite profile fiber of the present invention is preferably of fine single yarn fineness. To achieve finer single yarn fineness, it is necessary to reduce the amount of material ejected from each orifice during melt spinning, resulting in a lower shear rate within the orifice. Therefore, the distribution of the polymer into each orifice is at a low shear rate. However, in the case of polymers containing 30% or more of inorganic particles, the shear rate is significantly reduced within 25 s. -1 Even at the following low shear rates, the melt shear viscosity increases several times. The main reason for this is that when inorganic particles are present in a high concentration in the polymer, the shear stress increases due to the interaction between these particles, leading to an increase in melt shear viscosity. As a result, viscosity differences arise due to slight variations in shear rate within each pore, causing differences in distribution and making the profile formation of the composite profile unstable. Therefore, the inventors focused on the melt viscosity of the polymer as the matrix and discovered that by setting the degree of polymerization (intrinsic viscosity, relative viscosity, etc.) of the base polymer containing a high concentration of inorganic particles that determine melt viscosity below a certain value, and by defining the range of melt viscosity differences in the combined polymers, they suppressed the increase in melt shear viscosity, resulting in uniform distribution of the polymer to each pore of the die orifice, thereby suppressing the fiber profile CV% to below 10%.

[0045] In the melt spinning of the multilayer laminated composite profile fiber of the present application, the difference in the melt viscosity of the polymers used in the present application is also important from the viewpoint of improving the stable jetting property and the profile formation property. In order to make the pressure loss of the two polymers forming the composite flow uniform at the contraction, the cross-sectional area of the two polymers in the profile perpendicular to the flow direction of the polymers is changed, as a result, the flow rate difference occurs, and the center of gravity of each component is jetted with deviation, and thus the bending of the jetted polymer flow occurs. That is, the polymer having a high melt viscosity has a slow flow rate due to the large cross-sectional area, and on the contrary, the polymer having a low melt viscosity has a fast flow rate due to the small cross-sectional area. Therefore, by reducing the difference in the melt viscosity of the polymers used, the flow rate difference between the polymers is moderated, and the bending of the jetted polymer flow can be suppressed. If the above viewpoint is considered, it is preferable that the difference in the melt viscosity of the combined polymers is smaller. In addition, if the profile formation property is considered, it is preferable that the difference in the melt viscosity of the combined polymers is smaller. In view of the above, the difference in the melt viscosity of the combined polymers is particularly preferably in the range of 1000 poise or less.

[0046] As described above, the polymer containing inorganic particles at a high concentration has an increased melt viscosity due to the interaction of the inorganic particles, and thus in order to form a Figure 2 In order to uniformly arrange each layer in the profile form shown in FIG. 1, it is preferable that the polymer containing inorganic particles at a high concentration has a lower polymerization degree than the polymer of the outermost layer of the combined polymers.

[0047] In the case of the polyester, the intrinsic viscosity (hereinafter referred to as IV) is preferably in the range of 0.51 to 0.80. If the IV is 0.51 or more, the polymerization degree is not excessively low, and the composite fiber can have a strength sufficient to withstand practical use, and thus it is preferable. On the other hand, if the IV is 0.80 or less, the melt fracture does not occur, and a uniform multilayer laminated composite profile fiber can be obtained, and the strength does not decrease, and thus it is preferable. In the case where the polymer containing inorganic particles at a high concentration has a low polymerization degree, the profile formation property is excellent, and thus it is preferable that the IV is in the range of 0.51 to 0.65, and particularly preferably in the range of 0.51 to 0.60.

[0048] In the case of the polyester, the intrinsic viscosity (hereinafter referred to as IV) is preferably in the range of 0.51 to 0.80. If the IV is 0.51 or more, the polymerization degree is not excessively low, and the composite fiber can have a strength sufficient to withstand practical use, and thus it is preferable. On the other hand, if the IV is 0.80 or less, the melt fracture does not occur, and a uniform multilayer laminated composite profile fiber can be obtained, and the strength does not decrease, and thus it is preferable. In the case where the polymer containing inorganic particles at a high concentration has a low polymerization degree, the profile formation property is excellent, and thus it is preferable that the IV is in the range of 0.51 to 0.65, and particularly preferably in the range of 0.51 to 0.60.

[0049] As described above, in the multilayer laminated composite profile fiber of the present application, it is preferable that a thin layer is provided in the outermost layer, and a polymer layer containing inorganic particles at a high concentration is provided in at least one layer on the side closer to the center of the fiber than the outermost layer. The preferable inorganic particle content of the polymer layer containing inorganic particles at a high concentration is 30 to 70 mass%, and the preferable inorganic particle content of the outermost layer is 0.1 to 3.0 mass%. Furthermore, the inorganic particle content of the outermost layer is preferably 3.0 mass% or less, and in the case where the inorganic particle content greatly differs between adjacent layers, the polymer flowability at the time of melting greatly differs, and therefore, in order to uniformly form a thin layer in the outermost layer, the polymer component of the outermost layer preferably has a higher polymerization degree than the polymer components of the adjacent layers.

[0050] The multilayer laminated composite profile fiber of the present application is manufactured by a composite spinning machine that can melt two or more polymer components separately. It is preferable to be manufactured by a two-component composite spinning machine or a three-component composite spinning machine. At the time of melting the fiber-forming thermoplastic polymer, a pressure melting machine method or an extruder method can be exemplified, but there is no particular limitation. The melting temperature can be appropriately determined in consideration of the melting point of the fiber-forming thermoplastic polymer, and as a preferable melting temperature, the two or more polymer components are melted separately at a temperature that is 20 to 60°C higher than the melting point. The spinning temperature is the same as the melting temperature, and can be appropriately determined in consideration of the melting point of the fiber-forming thermoplastic polymer. Furthermore, the spinning temperature referred to here is the so-called heat retention temperature (spin block temperature) at which the polymer piping, the metering pump, the spinning die, and the like are heat retained.

[0051] The fiber-forming thermoplastic polymers that are melted separately are metered and supplied to the composite spinning die separately. Here, the two or more fiber-forming thermoplastic polymers are combined and formed into a multilayer laminated composite profile and are ejected from the die.

[0052] As the composite die used in the multilayer laminated composite profile fiber of the present application, it is preferable to use the composite die described in Japanese Patent Laid-Open No. 2011-208313. Figure 1 The composite die illustrated is assembled in a spinning pack in a state in which the metering plate 1, the distribution plate 2, and the ejection plate 3, which are roughly three kinds of members, are stacked from the top, and is used for spinning. Incidentally, Figure 1 is an example in which two kinds of polymers, an A polymer and a B polymer, are used, and if necessary, spinning can be performed using three or more kinds of polymers. In the existing composite die, it is difficult to composite three or more kinds of polymers, and it is still preferable to use a composite die such as Figure 1 the composite die that utilizes a fine flow path as exemplified in the drawing.

[0053] The yarns thus spun are cooled and solidified by a yarn cooling device, and are then given a spinning oil by an oil supply device, and are drawn out to produce drawn yarns by a two-step method in which the yarns are temporarily wound on a drum, or by a one-step method in which the yarns are not temporarily wound and are continuously drawn out. Alternatively, the yarns are not temporarily wound and are drawn out by appropriate spinning draft to produce semi-drawn yarns. These production methods will be described in detail.

[0054] In the production of semi-drawn yarns, the yarns are preferably drawn by appropriate spinning draft, and the spinning speed is preferably 3,000 m / min to 5,000 m / min.

[0055] If the ease of fiber structure formation in drawn yarns, i.e., the control of the tension from spinning to winding, is taken into consideration, a direct spinning and drawing method of the one-step method is preferred. The spinning speed is preferably 500 m / min to 6,000 m / min. The preheating temperature is preferably appropriately set based on the temperature at which the polymer can be softened, such as the glass transition temperature. As the upper limit of the preheating temperature, a temperature is preferably set at which yarns do not become disordered due to spontaneous elongation of the fibers during the preheating process. For example, in the case of PET in which the glass transition temperature is present near 70°C, the preheating temperature is usually set to about 80°C to 95°C. In the case of polyamide in which the glass transition point temperature decreases to room temperature due to moisture absorption, the preheating temperature need not be set, or is set to 25°C to 70°C.

[0056] In order to further impart functionality, the multi-layer laminated composite profile fiber of the present application can also be subjected to known yarn processing such as false twist processing, taslan processing, etc.

[0057] As for the false twist processing, it can be obtained by a known false twist processing method, and is preferably performed using an extension friction false twist processing device. If exemplified, it is as follows. For example, the semi-drawn yarns supplied to the extension friction false twist processing device are transported to a supply roller via a desired yarn path guide or a fluid treatment device. Then, they are guided to a drawing roller by a heated heater, a cooling plate, and a twisting body that performs extension friction false twist, and are wound as false twist processed yarns. As the extension friction false twist, it can be processing in which the yarns are subjected to friction false twist after being supplied to the supply roller of the extension friction false twist processing device and being drawn by a hot bar or a heated plate, or it can be processing in which the yarns are subjected to friction false twist while being drawn between the supply roller and the drawing roller.

[0058] The twisting body is not limited to a pin type or a friction type, a belt clamping type, etc. The pin type is preferred when crimping is to be enhanced, and the friction type or the belt clamping type is preferred when the processing speed is to be increased to reduce production costs.

[0059] As the heating method of the heater, a high-temperature contact-type heater or a high-temperature non-contact-type heater, etc. can be listed, and is not limited, but in order to obtain high crimping performance, it is necessary to actually add heat to the sliver by a high-temperature contact-type heater, to relax the strain by rearranging the molecules within the fiber. Therefore, a high-temperature contact-type heater is preferred, and the processing temperature, (heater set temperature in the contact-type hot plate) is preferably 170 to 200°C.

[0060] Examples

[0061] Hereinafter, the present application will be described more specifically by citing examples. Further, the measuring method of the characteristic values in the examples, etc. are as described below.

[0062] (1) Viscosity

[0063] A. Inherent viscosity (IV)

[0064] A 0.8 g polyester chip sample is dissolved in 10 mL of o-chlorophenol having a purity of 98% or more at a temperature of 25°C, and the relative viscosity ηr is calculated using an Ostwald viscometer at a temperature of 25°C using the following formula. Using the relative viscosity ηr, the inherent viscosity (IV) is calculated using the following formula.

[0065]

[0066]

[0067] Here,

[0068] η: viscosity of the polymer solution,

[0069] η0: viscosity of the o-chlorophenol,

[0070] t: falling time of the solution (sec),

[0071] d: density of the solution (g / cm 3 ),

[0072] t0: falling time of the o-chlorophenol (sec),

[0073] d0: density of the o-chlorophenol (g / cm 3 ).

[0074] B. Sulfuric acid relative viscosity (ηr)

[0075] A 0.25 g polyamide chip sample is dissolved to 1 g with respect to 100 ml of sulfuric acid having a concentration of 98% by weight, and the flow time T1 at 25°C is measured using an Ostwald-type viscometer. Then, the flow time T2 of only the sulfuric acid having a concentration of 98% by weight is measured. The ratio of T1 to T2, i.e., T1 / T2 is set as the 98% sulfuric acid relative viscosity.

[0076] (2) Total fineness, single yarn fineness

[0077] A measuring machine with a frame circumference of 1.0 m was used to make a 100 m skein, and the fineness was determined according to the following formula.

[0078] Total fineness (dtex) = 100 m skein weight (g) x 100

[0079] Single yarn fineness (dtex) = Total fineness (dtex) / number of filaments (roots).

[0080] (3) Strength, elongation

[0081] Determination was performed according to Japanese Industrial Standards (JIS) L1013 (2010, Test method for chemical fiber filament yarn).

[0082] (4) Composite profile (number of layers and outermost layer thickness)

[0083] The semi-drawn yarn and drawn yarn were cut at an arbitrary position in the fiber axis direction, and the fiber profile was observed using a microscope manufactured by KEYENCE at a magnification of 6000x, and the number of layers and the outermost layer thickness were determined.

[0084] The number of layers referred to here means the total number of layers in the multi-layer structure of each polymer component on a straight line (segment AB) drawn from an arbitrary point (A) on the outer circumference of the fiber profile of one fiber to the fiber center (B). Figure 2 Figure 2 The number of layers referred to here means the total number of layers in the multi-layer structure of each polymer component on a straight line (segment AB) drawn from an arbitrary point (A) on the outer circumference of the fiber profile of one fiber to the fiber center (B). Figure 2

[0085] In addition, the radius of the circle circumscribed to the cut surface of the fiber profile of one fiber was determined as the fiber radius X (segment AB) of the semi-drawn yarn or drawn yarn. Figure 2 Figure 2 Figure 2 Figure 2 Figure 2

[0086] In the case of false twist processed yarn, the theoretical fiber radius of the circle was calculated from the fineness of the false twist processed yarn, and was set as the fiber radius Z, because the profile shape was changed due to processing.

[0087] The outermost layer thickness of the false twist processed yarn was calculated using​​​​​​​

[0088] Outermost layer thickness of semi-drawn yarn (fiber radius X - fiber radius Y) x (fiber radius Z / fiber radius X of semi-drawn yarn)

[0089] Calculated.

[0090] Further, the specific gravity of the polyethylene terephthalate was set to 1.31, and the specific gravity of the polyamide was set to 1.13.

[0091] (5) Content of inorganic particles

[0092] A 7 g fiber sample was melted at 320°C, pressed at a maximum pressure of 100 kN, and the obtained product was used as a measurement sample, and the content of inorganic particles (g) was quantified using a wavelength dispersion type fluorescence X-ray analysis device ZSX Primus IV manufactured by RIGAKU Corporation.

[0093] The content of inorganic particles (mass%) of the entire fiber was calculated in the following manner.

[0094] Content of inorganic particles (mass%) = content of inorganic particles (g) / 7 (sample weight g) x 100

[0095] The content of inorganic particles (mass%) of one layer was calculated in the following manner.

[0096] A fiber sample (semi-drawn yarn, drawn yarn, false twist processed yarn) was cut at an arbitrary position in the fiber axial direction, and the fiber cross section was observed at a magnification of 6000 times using a microscope manufactured by KEYENCE, and in one fiber, a layer (black) in which the shade was darker than the outermost layer was selected, and the cross-sectional area ratio was measured. Five fibers were measured, and the average value was obtained.

[0097] In the case where the selected layer is one

[0098] Content of inorganic particles (mass%) of one layer = content of inorganic particles (mass%) of the entire fiber / cross-sectional area ratio

[0099] In the case where the selected layer is multiple

[0100] Content of inorganic particles (mass%) of one layer = content of inorganic particles (mass%) of the entire fiber / cross-sectional area ratio / number of selected layers.

[0101] (6) Sweat

[0102] According to necessity, the yarns are combined (2 in the case of 44 dtex) to make the extension yarn and the false twist processed yarn close to 88 dtex in total fineness, and a tubular knitted fabric is produced using a tubular knitting machine at a knitting density of 50 (number / 2.54 cm).

[0103] Then, the tubular knitted fabric is dyed light blue (brightness 45-50) by a blue dye, a water drop is dropped on the knitted fabric, and the color change degree is judged in 3 stages based on the following criteria by visual inspection by an inspector (5 people). As a result, the average value of the evaluation score of each inspector is taken, rounded off to the fourth decimal place, the average value of 3 points is set to, 2 points is set to, and 1 point is set to. 3 points and 2 points are set as qualified.

[0104] (3 points): No color change at all.

[0105] (2 points): The water drop dropping part looks slightly darker.

[0106] (1 point): The water drop dropping part looks significantly darker.

[0107] (7) Penetration resistance

[0108] A tubular knitted fabric is produced, a 1 cm x 5 cm black backing paper is attached to a white board, and the appearance of black is judged in 3 stages based on the following criteria by visual inspection by an inspector (5 people). As a result, the average value of the evaluation score of each inspector is taken, rounded off to the fourth decimal place, the average value of 3 points is set to, 2 points is set to, and 1 point is set to. 3 points and 2 points are set as qualified.

[0109] (3 points): Black is completely invisible.

[0110] (2 points): Black is slightly visible.

[0111] (1 point): Black is clearly visible.

[0112] (8) Hand feeling (softness)

[0113] A tubular knitted fabric is produced, and the hand feeling (softness) is judged in 3 stages based on the following criteria by the sense of touch of an inspector (5 people). As a result, the average value of the evaluation score of each inspector is taken, rounded off to the fourth decimal place, the average value of 3 points is set to, 2 points is set to, and 1 point is set to. 3 points and 2 points are set as qualified.

[0114] (3 points): Softness is strongly felt, and the hand feeling is good.

[0115] (2 points): Softness is felt.

[0116] (1 point): Hardness is felt, and the hand feeling is poor.

[0117] (9) UV cut-off property

[0118] A fabric was produced, and measurement was performed in accordance with JIS L1925 (2019, Evaluation method for ultraviolet shielding of fiber products). A value of 45 or more of the Ultraviolet Protection Factor (UPF) conversion value was set as having a UV cut-off property.

[0119] (10) Heat shielding property

[0120] A fabric was produced, and measurement was performed using a reflection lamp as a light source.

[0121] A thermocouple temperature sensor was disposed on the back of the sample in a non-contact manner so that the thermocouple temperature sensor absorbed heat (radiant heat) of sunlight transmitted through the sample. The rising temperatures of the thermocouple temperature sensor on which the sample was mounted and the heat ray light receiver of a control sample were measured, respectively, after irradiation of light for 15 minutes. A temperature difference of 2°C or more compared to a full dull type product (a single component fiber containing 1.5 mass% to 2 mass% of titanium oxide) was set as having a heat shielding property.

[0122] (11) Fiber cross-sectional area CV%, cross-sectional formation property

[0123] A fiber sample (semi-drawing yarn, drawing yarn, false twist processing yarn) was cut at an arbitrary position in the fiber axial direction, and a microscope manufactured by KEYENCE was used to observe the fiber cross section at a magnification of 6000 times, the fiber cross-sectional areas of all filaments were measured, and the CV% was calculated by the following formula.

[0124] Fiber cross-sectional area CV% = (standard deviation) / (average value) x 100

[0125] A case where the CV% was 10% or less was set as having a good cross-sectional formation property.

[0126] (12) Melt viscosity

[0127] The moisture regain of a sliced polymer was made 200 ppm or less by a vacuum drier, and the melt viscosity was measured by a CAPILOGRAPH IB manufactured by TOYO SEIKI KOGAKU K.K. by changing the strain speed in stages. In addition, the measurement temperature was the same as the spinning temperature, and the melt viscosity of 24.32 s -1 was recorded. Incidentally, the sample was put into a heating furnace for 5 minutes from the start of measurement, and the measurement was performed under a nitrogen atmosphere.

[0128] Example 1

[0129] A polyester (PET-A) containing 50 mass% of titanium oxide of rutile type in polyethylene terephthalate having an inherent viscosity of 0.56 was set as the intermediate layer. Polyethylene terephthalate (PET-B) having an inherent viscosity of 0.64 and containing 0.3 mass% of titanium oxide was set as the outermost layer and the inner layer. Further, the melt viscosity (290°C) was 670 poise (PET-A) and 1300 poise (PET-B).

[0130] Using a two-component composite spinning machine, for each component polymer, an individual extruder, polymer pipe, and metering pump were used to adjust the discharge amount in a manner that the composite ratio (weight ratio) of each layer becomes 21% for the outermost layer, 24% for the intermediate layer, and 55% for the inner layer (the composite ratio of PET-A:PET-B is 24:76), using a spinning temperature of 290°C, a composite nozzle temperature of 290°C, and a composite nozzle pressure of 20 MPa. Figure 1 The composite nozzle exemplified using a fine flow path discharges Figure 2 The three-layer concentrically laminated composite profile exemplified above.

[0131] The sliver discharged from the composite nozzle is cooled and solidified by passing through a sliver cooling device, is given a spinning oil agent by an oil supply device, and is then drawn at a draw roller speed (spinning speed) of 3000 m / min to obtain a 140 dtex-72 filament semi-drawn yarn (POY).

[0132] The obtained POY is drawn at a yarn speed of 450 m / min, a draw ratio of 1.7 times, and a heat treatment of 170°C (contact type hot plate heater set temperature) while implementing false twist processing (friction processing) to obtain an 84 dtex-72 filament (single yarn fineness 1.2 dtex) false twist processed yarn (DTY).

[0133] The outermost layer thickness of the DTY is . In addition, the inorganic particle content in the fiber was 12 mass%. The obtained circular knitted fabric was excellent in sweat stain suppression effect and permeation resistance, and a soft hand feeling was obtained. The results are shown in Table 1.

[0134] In addition, the obtained false twist processed yarn was used as weft yarn, and a plain fabric (warp: 188 / 2.54 cm, weft: 131 / 2.54 cm) was made using a 84 dtex-72 filament full-dull variety (polyethylene terephthalate drawn yarn containing 1.6 mass% of titanium oxide) in the warp. As a comparative product for the shielding property (UV cutoff property, heat shielding property) against sunlight, a fabric of the same design was used in which a 84 dtex-72 filament full-dull variety was used as weft yarn. The results of measuring the shielding property are shown in Table 4.

[0135] Examples 2, 3, Comparative Example 1

[0136] The ratio of the discharge amounts of the outermost layer and the inner layer was changed, and the thickness of the outermost layer was set to 0.5 μm (Example 2), (Example 3), (Comparative Example 1), and POY was obtained by spinning in the same manner as in Example 1 except that DTY was obtained. The results are shown in Table 1.

[0137] Comparative Example 2

[0138] A polyester (PET-C) containing 40 mass% of titanium oxide of rutile type in polyethylene terephthalate having an intrinsic viscosity of 0.56 was used as the core component, and PET-B was used as the sheath component. Further, the melt viscosity (290°C) of PET-C was 560 poise.

[0139] A two-component composite spinning machine was used, and for each component polymer, a separate extruder, polymer pipe, and metering pump were used, and the discharge amounts were adjusted so that the core component (PET-C) was 70% by weight and the sheath component (PET-B) was 30% by weight, a concentric core-sheath composite profile was formed using a composite die, and spinning was performed in the same manner as in Example 1 except that POY was obtained, and thus DTY was obtained. The results are shown in Table 1.

[0140] The thickness of the outermost layer of DTY was 0.5 μm . Further, the inorganic particle content in the fiber was 28 mass%. The results are shown in Table 1.

[0141] Example 4

[0142] A composite die of polyethylene terephthalate was arranged in the outermost layer (PET-B), the middle 2nd to 7th layers (PET-A, PET-B alternately stacked), and the innermost layer (PET-A), and a concentric eight-layer stacked composite profile was formed by changing the discharge ratio of the middle 2nd to 7th layers and the innermost layer (the composite ratio of PET-A:PET-B was 24:76) while maintaining the discharge ratio of the outermost layer at 21% by weight, and POY was obtained by spinning in the same manner as in Example 1 except that DTY was obtained. Further, the fiber profile of POY was observed by a microscope, and the results of the measurement were that there were 4 layers with deep shadows, and the sectional area ratio was 24%. The results are shown in Table 1.

[0143] Example 5

[0144] A composite die was configured with polyethylene terephthalate in the outermost layer (PET-B), the middle 2nd to 14th layers (alternately layered with PET-A and PET-B), and the innermost layer (PET-B), and POY was obtained by spinning under the same conditions as in Example 1 except that the concentric fifteen-layered composite profile was formed by changing the discharge ratio of the middle 2nd to 14th layers (the composite ratio of PET-A:PET-B was 24:76) while maintaining the discharge ratio of the outermost layer at 21%. The fiber profile of the POY was observed under a microscope, and the results of the measurement were that there were 7 layers with deep shading, and the area ratio of the profile was 24%. The results are shown in Table 1.

[0145] [Table 1]

[0146]

[0147] Examples 6 to 9, Comparative Example 3

[0148] The composition and discharge ratio of the middle layer were changed as shown in Table 2, and POY was obtained by spinning under the same conditions as in Example 1, and DTY was obtained. The results are shown in Table 2.

[0149] In addition, the melt viscosity (290°C) was 420 poise (PET-D) and 2400 poise (PET-E).

[0150] Example 10

[0151] A polyester (PET-I) containing 50 mass% of rutile-type titanium oxide in polyethylene terephthalate having an intrinsic viscosity of 0.70 was used as the middle layer, and POY was obtained by spinning under the same conditions as in Example 1, and DTY was obtained. The results are shown in Table 2.

[0152] The melt viscosity (290°C) of PET-I was 2800 poise, and the area CV% of the obtained DTY was 8%, which was a higher result than in Example 1.

[0153] Example 11

[0154] A recycled polyethylene terephthalate (PET-Re) having an intrinsic viscosity of 0.64, containing 0.3 mass% of titanium oxide, and prepared using recycled PET bottle chips as a raw material was used as the outermost layer and the inner layer, and POY was obtained by spinning under the same conditions as in Example 1, and DTY was obtained. The results are shown in Table 2.

[0155] The melt viscosity (290°C) of PET-Re was 1280 poise, which was a result comparable to that of Example 1.

[0156] [Table 2]

[0157]

[0158] Examples 12, 13, Comparative Example 4

[0159] The number of filaments, the ejection amount of the outermost layer, and the inner layer were changed as shown in Table 3, and otherwise, POY was obtained by spinning in the same manner as in Example 1, to thereby obtain DTY. The results are shown in Table 3.

[0160] [Table 3]

[0161]

[0162] Example 14

[0163] A polyamide (PA-F) containing 50 mass% of titanium oxide of rutile type in nylon 6 having a sulfuric acid relative viscosity of 2.20 and containing 0.02 mass% of titanium oxide was set as the intermediate layer. Nylon 6 (PA-G) having a sulfuric acid relative viscosity of 2.60 and containing 1.85 mass% of titanium oxide was set as the outermost layer and the inner layer. Further, the melt viscosity (280°C) was 1450 poise (PA-F) and 2250 poise (PA-G).

[0164] Using a two-component composite spinning machine, for each component polymer, an individual extruder, polymer pipe, and metering pump were used, and the ejection amount was adjusted in such a manner that the composite ratio (weight ratio) of each layer became 21% for the outermost layer, 24% for the intermediate layer, and 55% for the inner layer (the composite ratio of PA-F:PA-G was 24:76), and the yarn was spun at a spinning temperature of 280°C, a Figure 1 The composite die orifice using a fine flow path exemplified herein ejects Figure 2 The concentric three-layer laminated composite profile exemplified herein.

[0165] The yarn strand ejected from the composite die orifice was cooled and solidified by passing through a yarn strand cooling device, and then was given a spinning oil agent by a oil supply device, and thereafter was drawn at a draw roller speed (spinning speed) of 3000 m / minute, and was elongated at 1.3 times according to the peripheral speed ratio between the elongation rollers, and was heat set at 155°C, and was wound at a winding speed of 3900 m / minute, to thereby obtain an elongated yarn of 44 dtex-34 filaments (single yarn fineness 1.3 dtex). The outermost layer thickness of the elongated yarn was . Further, the inorganic particle content in the fiber was 12 mass%.

[0166] The obtained drawn yarn was made into a plain fabric of 165 ends / 2.54 cm, weft: 135 ends / 2.54 cm. Two pieces of the plain fabric were overlapped to measure the shielding property. The results are shown in Table 4. As a comparative sample of the shielding property, a plain fabric of the same design using a full-dull variety (nylon 6 drawn yarn containing 1.85 mass% titanium oxide) of 44 dtex-34 filament was used. The results of the measurement of the shielding property are shown in Table 4.

[0167] Example 15

[0168] A polyamide (PA-H) containing 1.5 mass% titanium oxide in nylon 610 of a sulfuric acid relative viscosity of 2.70 was set as the outermost layer and the inner layer, and otherwise, spinning was performed in the same manner as in Example 14 to obtain a drawn yarn. The results are shown in Table 4. Further, the melt viscosity (280°C) was 1100 poise (PA-H).

[0169] [Table 4]

[0170]

[0171] Example 16

[0172] A polyamide (PA-J) containing 50 mass% titanium oxide of rutile type in nylon 6 of a sulfuric acid relative viscosity of 2.60 containing 0.02 mass% titanium oxide was set as the intermediate layer, and otherwise, spinning was performed in the same manner as in Example 14 to obtain a drawn yarn. The results are shown in Table 5.

[0173] Further, the melt viscosity (280°C) was 7500 poise (PA-J), and the fiber profile CV% was 9%, and the profile formability was slightly inferior to that of Example 14.

[0174] Example 17

[0175] Nylon 6 (PA-K) of a sulfuric acid relative viscosity of 2.60 containing 0.20 mass% titanium oxide was set as the outermost layer and the inner layer, and otherwise, spinning was performed in the same manner as in Example 14 to obtain a drawn yarn. The results are shown in Table 5. Further, the melt viscosity (280°C) was 2200 poise (PA-K).

[0176] Example 18

[0177] In the same manner as in Example 14, the yarns discharged from the composite die were cooled and solidified by the yarn cooling device, and then, the spinning oil was applied by the oil supply device, and thereafter, drawing was performed at a drawing roll speed (spinning speed) of 3500 m / minute, and drawing was performed at 1.2 times according to the peripheral speed ratio between the drawing roll and the extension roll, and then, winding was performed at a winding speed of 4200 m / minute to obtain a semi-drawn yarn (POY) of 52 dtex-34 filament.

[0178] Using the extension friction false twist processing device, the obtained POY was extended at a yarn speed of 650 m / min, an extension ratio of 1.5 times, and a heat treatment of 160°C (contact type hot plate heater set temperature), while false twist processing (friction processing) was performed, to obtain a false twist processed yarn (DTY) of 44 dtex-34 filament (single yarn fineness of 1.3 dtex). The results are shown in Table 5.

[0179] Examples 19, 20

[0180] The ejection amount of the outermost layer and the inner layer was changed as shown in Table 5, and the outermost layer thickness was set to 2.5 dtex. (Example 19), (Example 20), and otherwise, spinning was performed in the same manner as in Example 14 to obtain an extended yarn. The results are shown in Table 5.

[0181] Examples 21, 22

[0182] The number of filaments was changed as shown in Table 6, and otherwise, spinning was performed in the same manner as in Example 14 to obtain an extended yarn. The results are shown in Table 6.

[0183] Example 23

[0184] The ejection amount was adjusted so that the composite ratio (weight ratio) of each layer would be 21% for the outermost layer, 10% for the intermediate layer, and 69% for the inner layer (the composite ratio of PA-F:PA-G was 10:90), and otherwise, spinning was performed in the same manner as in Example 14 to obtain an extended yarn. The results are shown in Table 6.

[0185] Example 24

[0186] A polyamide (PA-L) containing 60% by mass of titanium oxide of the rutile type in nylon 6 containing 0.02% by mass of titanium oxide with a sulfuric acid relative viscosity of 2.20 was set as the intermediate layer, and the ejection amount was adjusted so that it would be 21% for the outermost layer, 50% for the intermediate layer, and 29% for the inner layer (the composite ratio of PA-L:PA-G was 50:50), and otherwise, spinning was performed in the same manner as in Example 14 to obtain an extended yarn. The results are shown in Table 6. Furthermore, the melt viscosity (280°C) was 3300 poise (PA-L).

[0187] Example 25

[0188] A recycled polyamide (PA-Re) of a material that was remelted using nylon 6 chips (fiber chips that were abnormal in terms of weight or were unqualified in terms of product screening) containing 1.85% by mass of titanium oxide with a sulfuric acid relative viscosity of 2.60 was set as the outermost layer and the inner layer, and otherwise, spinning was performed in the same manner as in Example 14 to obtain an extended yarn. The results are shown in Table 6.

[0189] The melt viscosity (280°C) of PA-Re was 2220 poise, which was not inferior to the result of Example 14.

[0190] [Table 5]

[0191]

[0192] [Table 6]

[0193]

[0194] Industrial Applicability

[0195] By the multilayer laminated profile fiber of the present application, a cloth having sweat stain suppression, high permeation resistance, UV cut-off, heat insulation, soft hand feeling, which is most suitable for spring and summer clothing use, can be provided.

[0196] The present application has been described in detail with reference to specific embodiments, but it is apparent to those skilled in the art that various changes or modifications can be applied without departing from the spirit and scope of the present application.

[0197] This application is based on Japanese Patent Application (Japanese Patent Application No. 2023-43721) filed on March 20, 2023, the content of which is incorporated herein by reference in its entirety.

[0198] Explanation of Reference Signs

[0199] 1: Measuring plate

[0200] 2: Distributing plate

[0201] 3: Discharge plate

[0202] A: Arbitrary point of the outer periphery of the fiber profile

[0203] B: Fiber center

[0204] C: Polymer layer present further inside than the circle circumscribing the cross section of the fiber profile

[0205] D: Arbitrary point on the circumscribed circle of the polymer layer present further inside than the circle circumscribing the cross section of the fiber profile

Claims

1. A multilayer composite profile fiber, comprising at least two polymer components stacked parallel to the fiber surface in 3 to 15 layers in a fiber profile perpendicular to the fiber axis, wherein the outermost layer of the multilayer structure has a thickness of [missing information]. It contains 5% to 40% by mass of inorganic particles relative to the fiber as a whole, and the single yarn fineness is 0.7 dtex to 3.5 dtex.

2. The multilayer laminated composite cross-sectional fiber according to claim 1, wherein, The inorganic particles are contained in at least one layer that is closer to the fiber center than the outermost layer.

3. The multilayer laminated composite profile fiber according to claim 1 or 2, wherein, The two or more polymer components constituting the multilayer structure are either polyesters or polyamides.

4. The multilayer laminated composite profile fiber according to claim 1 or 2, wherein, In a fiber cross-section perpendicular to the fiber axis, the fiber cross-sectional area variation coefficient is less than 10%.

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