WO2020262511A1

WO2020262511A1 - Sheath-core composite yarn and fabric

Info

Publication number: WO2020262511A1
Application number: PCT/JP2020/024943
Authority: WO
Inventors: 吉岡大輔; 栗林隆宏; 河野健明
Original assignee: 東レ株式会社
Priority date: 2019-06-28
Filing date: 2020-06-25
Publication date: 2020-12-30
Also published as: JPWO2020262511A1; TW202113176A

Abstract

A sheath-core composite yarn wherein: a sheath part polymer is a polyamide and a core part polymer is a polyether ester amide copolymer; the time to the start of heat generation due to oxidative heat generation is 100 hours or more if subjected to a heat treatment at 150°C; and the change in the degree of yellowing (YI) after a treatment at 70°C for 8 hours is 10 or less.　The present invention provides a moisture-absorbing sheath-core composite yarn which has moisture absorbing/releasing properties, while being free from yellowing. The present invention also provides a moisture-absorbing sheath-core composite yarn which has excellent yellowing resistance, while maintaining a soft texture, good durability and moisture absorbing/releasing properties even after repeated washing and drying.

Description

Core sheath composite yarn and fabric

The present invention relates to a core-sheath composite yarn and a fabric having hygroscopicity.

Synthetic fibers made of thermoplastic resins such as polyamide and polyester are widely used in clothing and industrial applications because of their excellent strength, chemical resistance, and heat resistance. In particular, polyamide fibers have excellent hygroscopicity in addition to their unique softness, high tensile strength, color development during dyeing, and high heat resistance, and are widely used in applications such as innerwear and sportswear. .. However, polyamide fibers do not have sufficient hygroscopicity as compared with natural fibers such as cotton, and have problems such as stuffiness and stickiness, and are inferior to natural fibers in terms of comfort. ..

From such a background, synthetic fibers that show excellent moisture absorption and desorption to prevent stuffiness and stickiness and have comfort close to that of natural fibers are mainly requested for inner applications and sports clothing applications.

Therefore, by making the fiber structure a core-sheath structure, a core-sheath structure with a highly hygroscopic thermoplastic resin as the core and a thermoplastic resin with excellent mechanical properties as the sheath, moisture absorption performance and mechanical properties are achieved. There are many studies to achieve both.

For example, Patent Document 1 describes a core-sheath composite cross-sectional fiber having a thermoplastic polymer as a core and a fiber-forming polyamide as a sheath, and the main component of the thermoplastic polymer forming the core is a polyether ester. A core-sheath composite cross-section fiber which is an amide copolymer and has an excellent moisture absorption / desorption performance, characterized in that the ratio of the core portion is 5 to 50% by weight of the total weight of the composite fiber, is disclosed.

Further, in Patent Document 2, a polyalkylene oxide modified product obtained by reacting a polyalkylene oxide with a polyol and an aliphatic diisocyanate compound is used as a moisture absorbing / releasing component, and the fiber structure component is polyamide, which is a hindered amine type or phosphite. There is a description about woven and knitted fabrics to which a system antioxidant is added to maintain whiteness.

Further, in Patent Document 3, the sheath polymer is a polyamide and the core polymer is a polyether ester amide copolymer, and by suppressing the thermal deterioration of the core polymer, it is soft even if washing and drying are repeated. A core-sheath composite yarn capable of maintaining texture, durability and moisture absorption / desorption performance is disclosed.

Further, in Patent Document 4, the sheath polymer is polyester, the core polymer is polyester and polyoxyethylene-based polyether, and a specific amount of half-hindered phenol compound is used as an antioxidant to reduce the amount of alkali. A polyester core-sheath composite yarn having extremely excellent yellowing resistance, which can maintain the initial whiteness level as it is even after being processed, is disclosed.

Japanese Unexamined Patent Publication No. 06-136618 Japanese Unexamined Patent Publication No. 2000-336560 International Publication No. 2017/098861 JP-A-04-15320

However, although the fibers described in Patent Document 1 have moisture absorption and desorption properties, the core component is thermally deteriorated by continuous use of a household washer / dryer, so that the fibers are hardened and the texture of the fabric is hardened. There is a problem that durability and moisture absorption / desorption performance are deteriorated. In addition, although there is a description of an antioxidant, there is no suggestion about a specific formulation.

Although the fibers described in Patent Document 2 have examples of hindered amines and phosphite-based heat-resistant agents, they can maintain whiteness, but the core component is thermally deteriorated by continuous use of a household washer / dryer. There is a problem that the texture becomes hard and the durability and the moisture absorption / desorption performance are deteriorated.

The fibers described in Patent Document 3 have moisture absorption and desorption properties, and can maintain a soft texture, durability and moisture absorption and desorption performance without heat deterioration due to continuous use of a household washer / dryer, but over time. There was a problem that yellowing progressed, and further improvement was required.

The fiber described in Patent Document 4 has a polyester sheath polymer, and half-hindered phenol is inactivated by washing with water to which a bleaching agent is added. Therefore, the core component is thermally deteriorated by continuous use of a household washer / dryer. However, there is a problem that the texture of the fabric becomes hard and the durability and antistatic performance are lowered.

The present invention has the following configuration in order to solve the above problems.

(1) The sheath polymer is a polyamide and the core polymer is a polyether ester amide copolymer, and when heat-treated at 150 ° C., the time until the start of heat generation due to oxidative heat generation is 100 hours or more, and 70 ° C. A core-sheath composite yarn characterized in that the change in yellowness (YI) (ΔYI) after a dry heat treatment for 8 hours is 10 or less.

(2) The core-sheath composite yarn according to (1), wherein the ΔMR is 5.0% or more, and the ΔMR retention rate after a dry heat treatment at 150 ° C. for 1 hour is 70% or more.

(3) The core-sheath composite yarn according to (1) or (2), wherein the yellowness (YI ₀ ) after dry heat treatment at 70 ° C. for 8 hours is 13 or less.

(4) A fabric having at least a part of the core-sheath composite yarn according to any one of (1) to (3).

According to the present invention, it is possible to provide a hygroscopic core-sheath composite yarn having hygroscopicity and no yellowing. Further, a hygroscopic core-sheath composite yarn having a soft texture, durability and moisture absorption / desorption performance and excellent yellowing resistance can be obtained even after repeated washing and drying.

Schematic diagram of the oxidation heat generation measuring apparatus of the present invention

The core-sheath composite yarn of the present invention uses polyamide for the sheath and a polyether ester amide copolymer for the core.

A polyether ester amide copolymer is a block copolymer having an ether bond, an ester bond and an amide bond in the same molecular chain. More specifically, one or more polyamide components (A) selected from lactam, aminocarboxylic acid, diamine and dicarboxylic acid salts, and a polyether ester component consisting of dicarboxylic acid and poly (alkylene oxide) glycol (. It is a block copolymer polymer obtained by subjecting B) to a polycondensation reaction.

The polyamide component (A) includes lactams such as ε-caprolactam, dodecanolactam, and undecanolactam, ω-aminocarboxylic acids such as aminocaproic acid, 11-aminoundecanoic acid, and 12-aminododecanoic acid, nylon 66, and nylon. There are nylon salts of diamine-dicarboxylic acid which are precursors such as 610 and nylon 612, and a preferable polyamide-forming component is ε-caprolactam.

The polyether ester component (B) is composed of a dicarboxylic acid having 4 to 20 carbon atoms and a poly (alkylene oxide) glycol. Examples of dicarboxylic acids having 4 to 20 carbon atoms include aliphatic dicarboxylic acids such as succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, sebacic acid, and dodecadic acid, terephthalic acid, isophthalic acid, and 2,6-naphthalenedicarboxylic acid. Such as aromatic dicarboxylic acid and alicyclic dicarboxylic acid such as 1,4-cyclohexanedicarboxylic acid can be mentioned, and one kind or a mixture of two or more kinds can be used. Preferred dicarboxylic acids are adipic acid, sebacic acid, dodecadic acid, terephthalic acid and isophthalic acid. Examples of the poly (alkylene oxide) glycol include polyethylene glycol, poly (1,2- and 1,3-propylene oxide) glycol, poly (tetramethylene oxide) glycol, poly (hexamethylene oxide) glycol and the like. Polyethylene glycol having good moisture absorption performance is preferable.

The number average molecular weight of the poly (alkylene oxide) glycol is preferably 300 to 5000, more preferably 500 to 4000. When the molecular weight is 300 or more, it is difficult to scatter to the outside of the system during the polycondensation reaction, and the fiber has stable hygroscopic performance, which is preferable. Further, when it is 5000 or less, poly (alkylene oxide) glycol is uniformly dispersed in the polymer, and good hygroscopic performance can be obtained, which is preferable.

The composition ratio of the polyether ester component (B) in the entire polyether ester amide copolymer is preferably 20 to 80% in terms of molar ratio. When it is 20% or more, good moisture absorption performance can be obtained, which is preferable. Further, when it is 80% or less, it is preferable because good dyeing fastness and washing durability with hygroscopic performance can be obtained.

The composition ratio of polyamide and poly (alkylene oxide) glycol is preferably 20% / 80% to 80% / 20% in terms of molar ratio. When the poly (alkylene oxide) glycol is 20% or more, good hygroscopic performance can be obtained, which is preferable. Further, when the poly (alkylene oxide) glycol is 80% or less, good dyeing fastness and washing durability with hygroscopic performance can be obtained, which is preferable.

As such a polyether ester amide copolymer, "MH1657" and "MV1074" manufactured by Arkema Co., Ltd. are commercially available.

The polyamide of the sheath includes nylon 6, nylon 66, nylon 46, nylon 9, nylon 610, nylon 11, nylon 12, nylon 612, etc., or compounds having amide-forming functional groups thereof, such as laurolactam and sebacic acid. Examples thereof include copolymerized polyamides containing copolymerizing components such as terephthalic acid, isophthalic acid, and 5-sodium sulfoisophthalic acid. Among them, nylon 6 and nylon 11, nylon 12, nylon 610, and nylon 612 have a small difference in melting point from the polyether ester amide copolymer, and can suppress thermal deterioration of the polyether ester amide copolymer during melt spinning. , Preferable from the viewpoint of yarn-making property. Of these, nylon 6 is preferably dyeable.

The core-sheath composite yarn of the present invention has a time of 100 hours or more until the start of heat generation due to oxidative heat generation when heat-treated at 150 ° C. The core component, the polyether ester amide copolymer, generates heat when it starts oxidative decomposition, but by suppressing the oxidative heat generation over the required time, after repeated execution in a household washer / dryer (hereinafter referred to as tumble drying). The core component does not oxidatively decompose or denature, and can maintain a soft texture, durability, and moisture absorption / desorption performance. If it is less than 100 hours, repeated tumble drying will promote thermal deterioration of the polyether ester amide copolymer, hardening and embrittlement of the raw yarn, and deterioration of moisture absorption performance, and the texture will change each time the yarn is washed and dried. It becomes hard and the durability and moisture absorption / desorption performance of the fabric are reduced. It is preferably 150 hours or more.

The core-sheath composite yarn of the present invention has a yellowness (YI) change ΔYI of 10 or less. Since clothing fibers are dyed in various colors, they are desired to be colorless to white. If the fibers are yellowed, the color development after light color dyeing becomes dull, and there may be restrictions such as limited use for dark color dyeing. It is desired that even if the yarn is colorless to white immediately after the production of the raw yarn, it does not yellow over time even during the storage period of the raw yarn and the period from the production of the raw yarn to the dyeing. It can be used as a fiber for use. As an index of yellowing over time, the degree of yellowing (ΔYI) represented by the difference in yellowness before and after 8 hours of treatment in a thermostat at 70 ° C. and 45% RH temperature and humidity is used. The smaller ΔYI is, the more yellowing does not occur with time, and the better the yellowing resistance. It is more preferably 5 or less, and particularly preferably 3 or less.

Further, it is preferable that the yellowness (YI ₀ ) after 8 hours of treatment in a thermostat at 70 ° C. and 45% RH temperature and humidity is 13 or less. Within this range, not only yellowing over time, but also yellowing due to heat history (dyeing of fabric, heat setting, etc.) during higher-order processing processes, and yellowing even after repeated tumble drying, and color tone A fabric that does not change can be obtained.

The core-sheath composite yarn of the present invention has a function of adjusting the humidity inside the garment in order to obtain good comfort when worn. As an index of humidity adjustment, the temperature and humidity inside clothes represented by 30 ° C x 90% RH and the outside air temperature and humidity represented by 20 ° C x 65% RH when performing light to medium work or light to medium exercise. ΔMR represented by the difference in moisture absorption rate is used. The larger the ΔMR, the higher the hygroscopic performance, which corresponds to the good comfort when worn.

The core-sheath composite yarn of the present invention preferably has a ΔMR of 5.0% or more. More preferably, it is 7.0% or more. Within such a range, stuffiness and stickiness at the time of wearing can be suppressed, and it becomes possible to provide clothing having excellent comfort.

The core-sheath composite yarn of the present invention preferably has a ΔMR retention rate of 70% or more and 100% or less after a dry heat treatment at 150 ° C. for 1 hour. Within such a range, it is possible to maintain the moisture absorption / desorption performance even if tumble drying is repeatedly performed, and it is possible to provide clothing having excellent comfort. More preferably, it is 80% or more.

The polyether ester amide copolymer used for the core of the present invention contains poly (alkylene oxide) glycol, and the poly (alkylene oxide) glycol generates radicals from inside the molecule due to heat application and is adjacent to the copolymer. A chain reaction such as the generation of radicals by attacking the atoms is carried out, and the heat of the reaction causes the temperature to exceed 200 ° C. Further, the smaller the molecular weight of the poly (alkylene oxide) glycol, the easier it is to apply heat to the molecular chain, so that radicals are likely to be generated and reaction heat tends to be generated.

Since the number average molecular weight of the poly (alkylene oxide) glycol contained in the polyether ester amide copolymer used in the present invention is relatively small, 300 to 5000, the heat deterioration of the polyether ester amide copolymer is caused by the above mechanism. Is easy to proceed, and it is very easy to cause hardening and brittleness of the raw yarn, deterioration of moisture absorption performance, and the like.

Therefore, an antioxidant that captures radicals is added to the polyether ester amide copolymer in the core. However, with both hindered phenolic stabilizers, which are generally used as antioxidants with a radical-supplementing effect, the thermal history during the spinning process (high temperature applied during polymer melting and heat set after stretching) and higher-order processing Due to the heat history during the process (dyeing of fabric, heat setting, etc.), the thermal deterioration of the polyether ester amide copolymer progresses, and the amount of active component of the antioxidant that captures the radicals remaining at the stage of fabric and clothing is large. Decreases to. Further, in the subsequent actual use, if the tumble drying is repeatedly carried out, the thermal deterioration of the polyether ester amide copolymer progresses, the hardening and embrittlement of the raw yarn, the deterioration of the moisture absorption performance and the like progress. As described in Patent Document 3, in order to suppress a decrease in the amount of the active ingredient of the antioxidant that captures radicals, a method of using a hindered phenol-based stabilizer and a hindered amine-based stabilizer (HALS) in combination was proposed and tumbled. Even after repeated drying, the soft texture, durability and moisture absorption / desorption performance could be maintained. However, in such a method, HALS is denatured into a coloring decomposition product by heat and colored, or because HALS is basic, a dimer of hindered phenol or the like is generated and colored. The fabric turns yellow due to the history. On the other hand, there is a method of adding a large amount of hindered phenol, but coloring by a decomposed product of hindered phenol is unavoidable. In order to suppress radical generation of the polyether ester amide copolymer in the core, suppress reaction heat and thermal deterioration (prevent oxidative heat generation), and suppress yellowing, half-hindered phenol-based oxidation Inhibitors are effective.

Compared with both hindered phenol-based stabilizers, half-hindered phenol-based antioxidants reduce the amount of active component of the antioxidant in the heat history during the spinning process and the heat history during the higher-order processing process. Is very small. Therefore, the reaction heat and thermal deterioration can be suppressed by using the half-hindered phenol-based stabilizer alone without using the hindered amine-based stabilizer (HALS) in combination like both hindered phenol-based stabilizers, and the temperature is 150 ° C. It is possible to set the time until the start of heat generation due to oxidative heat generation to 100 hours or more when the heat treatment is performed in. Further, since the decomposed product of half-hindered phenol is less colored, yellowing can be suppressed and the ΔYI value can be set to 10 or less.

The amount of the half-hindered phenolic stabilizer added during the production of the core-sheath composite yarn of the present invention is 1.0% by weight or more and 5.0% by weight with respect to the weight of the polyether ester amide copolymer in the core portion. The following is preferable. More preferably, it is 2.0% by weight or more. By setting the content to 1.0% by weight or more, the heat of reaction and thermal deterioration can be suppressed, and the time until the start of heat generation due to oxidative heat generation when heat-treated at 150 ° C. can be set to 100 hours or more. Further, even if tumble drying is repeatedly carried out, hardening and embrittlement of the raw yarn can be prevented, and soft texture, durability and moisture absorption / desorption performance can be maintained. When the content is 5.0% by weight or less, the yarn-forming property is improved and the yellowing of the raw yarn can be suppressed, which is preferable.

The half-hindered phenolic antioxidant used in the present invention is, for example, 2,2'-dimethyl-2,2'-(2,4,8,10-tetraoxaspiro [5.5] undecane-3,9. -Diyl) Dipropane-1,1'-Diyl-bis [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propanoart] (Sumitomo Chemical Co., Ltd. "Sumilyzer" (registered trademark) AG80, ADEKA "Adecastab" (registered trademark) AO-80), 1,3,5-tris [[4- (1,1-dimethylethyl) -3-hydroxy-2,6-dimethylphenyl] methyl] -1,3 , 4-Triazine-2,4,6 (1H, 3H, 5H) -trion (“Cyanox” (registered trademark) 1790 manufactured by Solvay).

Among them, 2,2'-dimethyl-2,2'-(2,4,8,10-tetraoxaspiro [5.5] undecane-3,9-diyl) dipropane-1,1'-diyl-bis [3- (3-tert-Butyl-4-hydroxy-5-methylphenyl) propanoate] (Adecastab AO-80) is preferred.

In the present invention, other phosphorus-based and hindered amine-based stabilizers can be used in combination with the core polyether ester amide copolymer. In addition, various other additives such as matting agents, flame retardants, ultraviolet absorbers, infrared absorbers, crystal nucleating agents, fluorescent whitening agents, antistatic agents, hygroscopic polymers, carbon, etc. are all added. The content may be copolymerized or mixed as required in the range of 0.001 to 10% by weight based on the whole fiber.

In the present invention, various additives such as a matting agent, a flame retardant, an ultraviolet absorber, an infrared absorber, a crystal nucleating agent, a bright whitening agent, an antistatic agent, and a hygroscopic polymer are applied to the polyamide of the sheath portion. , Carbon and the like may be copolymerized or mixed as required with a total additive content of 0.001 to 10% by weight based on the total fiber content.

The core-sheath composite yarn of the present invention preferably has an elongation of 35% or more. More preferably, it is 40 to 80%. Within such a range, the process passability in higher-order processes such as weaving, knitting, and false twisting becomes good.

The total fineness and the number of filaments of the core-sheath composite yarn of the present invention are not particularly limited, and the cross-sectional shape can be any shape depending on the application of the fabric. Considering the use as a long fiber material for clothing, the total fineness as a multifilament is preferably 5 decitex or more and 235 decitex or less, and the number of filaments is preferably 1 or more and 144 filaments or less. Further, the cross-sectional shape is not particularly limited to circular, triangular, flat, Y-shaped, and star-shaped, and the composite form is not limited, but the eccentric type and the bonded type are preferable.

The core-sheath composite yarn of the present invention can be obtained by a known method of melt spinning and composite spinning, and examples are as follows.

For example, polyamide (sheath part) and polyether ester amide copolymer (core part) are melted separately, weighed and transported by a gear pump, and a composite flow is formed so as to take a core-sheath structure as it is by a usual method. The yarn is discharged from the spun cap and blown with cooling air by a yarn cooling device such as a chimney to cool the yarn to room temperature, refueled by the lubrication device and focused, entangled by the first fluid entanglement nozzle device, and a take-up roller. , Passing through a stretching roller, at which time stretching is performed according to the ratio of the peripheral speeds of the take-up roller and the stretching roller. Further, the yarn is heat-set by a drawing roller and wound by a winder (winding device).

In the spinning process, the temperature of the molten part of the core polymer is preferably 235 ° C. or higher and 260 ° C. or lower. When the temperature of the molten portion of the core polymer is 235 ° C. or higher, the polyether ester amide copolymer in the core has a melt viscosity suitable for melt spinning, which is preferable. When the temperature is 260 ° C. or lower, thermal decomposition of the polytel ester amide copolymer and decomposition of the half-hindered phenolic antioxidant can be suppressed, and yellowing can be suppressed, which is preferable. More preferably, it is 240 ° C. or lower. The temperature of the melted portion of the sheath polymer is preferably 240 ° C. or higher and 285 ° C. or lower. When the temperature of the molten portion of the sheath polymer is 240 ° C. or higher, the polyamide in the sheath has a melt viscosity suitable for melt spinning, which is preferable. When the temperature is 285 ° C. or lower, thermal decomposition due to an increase in the temperature of the polytel ester amide copolymer in the core portion and decomposition of the half-hindered phenolic antioxidant can be suppressed, and yellowing can be suppressed, which is preferable. More preferably, it is 260 ° C. or lower. The temperature of the molten portion at the confluence is preferably 235 ° C. or higher and 270 ° C. or lower. When the temperature is 235 ° C. or higher, the polyamide and the polyether ester amide copolymer have a melt viscosity suitable for melt spinning, which is preferable. When the temperature is 270 ° C. or lower, thermal decomposition of the polyether ester amide copolymer and decomposition of the half-hindered phenolic antioxidant can be suppressed, and yellowing can be suppressed, which is preferable. More preferably, it is 260 ° C. or lower.

The ratio of the core portion of the core-sheath composite yarn of the present invention is 20% by weight to 80% by weight with respect to the entire composite yarn. More preferably, it is 30% by weight to 70% by weight. Within such a range, it is possible to apply appropriate stretching to the polyamide of the sheath portion. In addition, good dyeing fastness and hygroscopic performance can be obtained. If it is less than 20% by weight, sufficient hygroscopic performance may not be obtained. On the other hand, if it exceeds 80% by weight, not only the fiber surface is liable to be cracked due to swelling in a hot water atmosphere such as dyeing, but also excessive stretching is applied to the polyamide in the sheath portion, which may cause thread breakage or fluff. .. Further, spinning and drawing that generate excessive tension lead to yarn breakage and fluffing, which is not preferable for stable production of the target fiber.

The polyamide chip used for the sheath portion of the present invention preferably has a sulfuric acid relative viscosity of 2.3 or more and 3.3 or less. Within such a range, it is possible to apply appropriate stretching to the polyamide of the sheath portion.

The chip of the polyether ester amide copolymer polymer used for the core portion of the present invention preferably has an orthochlorophenol relative viscosity of 1.2 or more and 2.0 or less. When the relative viscosity of orthochlorophenol is 1.2 or more, an optimum stress is applied to the sheath portion during spinning, crystallization of the polyamide in the sheath portion proceeds, and the strength is increased, which is preferable.

The method of blending the half-hindered phenol-based oxidative spinning agent and the polyether ester amide copolymer is not particularly limited. For example, a method of adding the polyether ester amide copolymer at the start of polymerization and during the polymerization, a dry blend method in which a half-hindered phenol-based antioxidant is attached to the chip of the polyether ester amide copolymer, and two methods in advance. Using a shaft extruder or a single shaft extruder, a master chip containing a high concentration of half-hindered phenolic antioxidant in a polyether ester amide copolymer is produced, and this master chip and poly are used in the spinning process. Examples thereof include a master chip method of blending with an ether ester amide copolymer chip.

In the drawing step, the product of the speed of the yarn taken up by the take-up roller (spinning speed, m / min) and the drawing ratio, which is the value of the peripheral speed ratio of the take-up roller and the drawing roller, is 3300 or more and 4500 or less. It is preferable to set the spinning conditions. More preferably, it is 4000 or less. This numerical value represents the total drawing amount in which the polymer discharged from the mouthpiece is stretched from the mouthpiece discharge line speed to the peripheral speed of the take-up roller, and further from the peripheral speed of the take-up roller to the peripheral speed of the drawing roller. Within such a range, it is possible to apply appropriate stretching to the polyamide of the sheath portion. When it is 3300 or more, the crystallization of the polyamide in the sheath portion proceeds, so that the strength of the yarn is improved and heat resistance is obtained, which is preferable. On the other hand, when it is 4500 or less, crystallization of the polyamide in the sheath portion proceeds moderately, and yarn breakage and fluffing are less likely to occur during silk reeling, which is preferable.

Further, the heat setting temperature by the stretching roller is preferably 110 ° C. or higher and 160 ° C. or lower. When the temperature is 110 ° C. or higher, crystallization of nylon in the sheath portion is promoted, strength is improved, and drum winding is suppressed, which is preferable. Further, the temperature of 160 ° C. or lower is preferable because the thermal decomposition of the hindered phenolic antioxidant is suppressed.

In the refueling process, the spinning oil agent given by the refueling device is preferably a non-hydrous oil agent. Since the polyether ester amide copolymer in the core is a polymer having a ΔMR of 10% or more and has excellent hygroscopicity, when a non-hydrous oil is added, it gradually absorbs moisture in the air, causing swelling. It is preferable because it is difficult and stable winding is possible.

The core-sheath composite yarn of the present invention has excellent hygroscopicity and can be preferably used for clothing. As the fabric form, a woven fabric, a knitted fabric, a non-woven fabric, or the like can be selected according to the purpose. As described above, the larger the ΔMR, the higher the hygroscopic performance, which corresponds to the better comfort when worn. Therefore, the fabric having the core-sheath composite yarn of the present invention at least in a part is excellent in comfort by adjusting the mixing ratio of the core-sheath composite yarn of the present invention so that ΔMR is 5.0% or more. Clothing can be provided. As clothing, various clothing products such as innerwear and sportswear can be used.

Hereinafter, the present invention will be described in more detail with reference to examples. The method for measuring the characteristic value in the examples is as follows.

(1) Relative Sulfuric Acid Viscosity 0.25 g of a sample was dissolved in 100 ml of sulfuric acid having a concentration of 98 wt% so as to be 1 g, and the flow time (T1) at 25 ° C. was measured using an Ostwald viscometer. Subsequently, the flow time (T2) of sulfuric acid alone having a concentration of 98 wt% was measured. The ratio of T1 to T2, that is, T1 / T2, was defined as the relative viscosity of sulfuric acid.

(2) Relative viscosity of orthochlorophenol 0.5 g of a sample was dissolved in 100 ml of orthochlorophenol so as to be 1 g, and the flow time (T1) at 25 ° C. was measured using an Ostwald viscometer. Subsequently, the flow time (T2) of orthochlorophenol alone was measured. The ratio of T1 to T2, that is, T1 / T2, was defined as the relative viscosity of sulfuric acid.

(3) Set the fiber sample in a scale with a total fineness of 1.125 m / circumference, rotate it 200 times to make a loop-shaped skein, and dry it with a hot air dryer (105 ± 2 ° C x 60 minutes). The skein mass was weighed with a balance, and the total fineness was calculated from the value multiplied by the official moisture content. The official moisture content of the core-sheath composite yarn was 4.5%.

(4) Strength / Elongation Fiber samples are subjected to "TENSILON" (registered trademark) manufactured by Orientec Co., Ltd., under the constant speed elongation conditions shown in JIS L1013 (chemical fiber filament yarn test method, 2010) with UCT-100. It was measured. The elongation was determined from the elongation of the point showing the maximum strength in the tensile strength-elongation curve. The strength was defined as the value obtained by dividing the maximum strength by the total fineness. The measurement was performed 10 times, and the average value was taken as the intensity and elongation.

(5) Preparation of tubular knitted fabric The cylinder knitting machine was used to adjust the number of times to 50. If the positive fiber fineness is low, the fibers to be fed to the tubular knitting machine are appropriately combined so that the total fineness is 50 to 100 decitex, and if the total fineness exceeds 100 decitex, the yarn is added to the tubular knitting machine. The yarn was fed by one yarn and adjusted so that the degree was 50 in the same manner as described above.

(6) Start time of heat generation of oxidation The heat generation method of polypropylene fiber specified by the Chemical Fiber Association was followed as follows.
A. Preparation of Samples A cloth having a diameter of 50 mm was collected from the tubular knitted fabric described in (5), and the number of fabrics that could be stacked and filled to the depth (50 mm) of the cylindrical container was collected.
B. Pretreatment The washing carried out by the 103 method of JIS L0217 (1995) "Indication symbols and labeling methods for handling textile products" and tumble drying at about 60 ° C. for 30 minutes were carried out. Washing and drying were set as one set, and this was repeated for 10 sets.
C. Oxidation heat generation test The pretreated sample was placed in the cylindrical container shown in FIG. 1 and maintained at 150 ° C. in a constant temperature dryer. The time and temperature change after the temperature of the central part of the sample reached 150 ° C. was recorded, and the presence or absence of heat generation was confirmed. If no fever was observed in 100 hours, the oxidative fever test was passed.

(7) Moisture absorption and desorption ΔMR
(5) Weigh about 1 to 2 g of the described tubular knitted fabric into a weighing bottle, keep it at 110 ° C. for 2 hours, dry it, and measure the weight (W0). Next, the target substance is set to 20 ° C. and a relative humidity of 65% 24. After holding for a long time, the weight is measured (W65). Then, this is held at 30 ° C. and 90% relative humidity for 24 hours, and then the weight is measured (W90). Then, it was calculated according to the following formula.
MR65 = [(W65-W0) / W0] x 100% ... (1)
MR90 = [(W90-W0) / W0] x 100% ... (2)
ΔMR = MR90-MR65 ... (3).

(8) ΔMR after dry heat treatment
The tubular knitted fabric described in (5) was subjected to dry heat treatment with a hot air dryer (150 ± 2 ° C. × 60 minutes), and then the moisture absorption / desorption property ΔMR described above was measured and calculated.

(9) ΔMR retention rate after dry heat treatment The ΔMR retention rate after dry heat treatment was calculated by the following formula as an index of change in ΔMR before and after dry heat treatment.
(ΔMR after dry heat treatment / ΔMR before dry heat treatment) × 100.

(10) Change in yellowness (YI) (ΔYI)
The tubular knitted fabric described in (5) was measured according to JIS K7373 (Plastic-How to determine yellowness and yellowing, 2006) using a color computer manufactured by Suga Test Instruments Co., Ltd., and its yellowing resistance was evaluated. ..
ΔYI = YI-YI ₀
YI: Yellowness before heat treatment YI ₀ : Yellowness after heat treatment (treatment in a thermostat at 70 ° C. and 45% RH temperature and humidity for 8 hours).

(11) Tumble drying The tubular knitted fabric described in (5) is repeatedly dried at a temperature of 80 ° C. for 1 hour in the A1 type tumble dryer described in Appendix G of JIS L1930 (2014 home washing test method). It was carried out 10 times.

(12) Texture evaluation The texture of the tubular knitted fabric after tumble drying described in (11) was subjected to a relative evaluation by inspectors (5 persons). As a result, the average value of the evaluation points of each inspector was taken and rounded off to the nearest whole number, and the average value was 3 for S, 2 for A, and 1 for C.
S and A were accepted.
S: Very soft texture that is completely the same as before tumble drying A: Soft texture that does not change much compared to before tumble drying C: Texture that hardens and becomes stiff compared to before tumble drying.

(13) Color tone evaluation The color tone of the tubular knitted fabric after tumble drying described in (11) was evaluated in the following three stages. S and A were accepted.
S: ΔYI less than 0.9 A: ΔYI 0.9 or more, less than 5.0 C: ΔYI 5.0 or more.

(14) Moisture absorption performance For the tubular knitted fabric described in (5), the ΔMR described in (7) before and after tumble drying described in (11) was measured, and the retention rate was calculated. S and A were accepted.
S: 80% or more A: 70% or more and less than 80% C: Less than 70%.

[Example 1]
As a polyether ester amide copolymer, a polyether ester amide copolymer (alchema) in which the polyamide component is nylon 6, the polyether component is polyethylene glycol having a molecular weight of 1500, and the molar ratio of nylon 6 to polyethylene glycol is 24%: 76%. Co., Ltd., MH1657, orthochlorophenol relative viscosity: 1.69) A chip was used for the core. In addition, a half-hindered phenol-based antioxidant: 2,2'-dimethyl-2,2'-(2,4,8,10) was added to the polyether ester amide copolymer at a high concentration in advance using a twin-screw extruder. -Tetraoxaspiro [5.5] undecane-3,9-diyl) dipropane-1,1'-diyl-bis [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propanoart] (ADEKA) A master chip containing Adecastab AO-80) manufactured by Adecastab AO-80) and a polyether ester amide copolymer chip were blended and adjusted to be 3.0% by weight based on the weight of the core. As the polyamide, a nylon 6 chip having a relative sulfuric acid viscosity of 2.63 was used for the sheath portion.

The above-mentioned polyether ester amide copolymer is used as a core, nylon 6 is used as a sheath, and the core is melted at a core melt temperature of 235 ° C, a sheath melt temperature of 260 ° C, and a confluence melt temperature of 255 ° C. The core / sheath ratio (% by weight) was spun from the sheath composite mouthpiece so as to be 30/70. At this time, the rotation speed of the gear pump is selected so that the total fineness of the obtained core-sheath composite yarn is 56 decitex, the yarn is cooled and solidified by the yarn cooling device, and the non-hydraulic oil is lubricated by the lubrication device. Entanglement is applied by the first fluid entanglement nozzle device, the peripheral speed of the take-up roller which is the first roll is 2426 m / min, the peripheral speed of the stretching roller which is the second roll is 3590 m / min, and the stretching ratio is 1.48 times. The heat was set by a drawing roller at 150 ° C., and the winding speed was 3500 m / min to obtain a core-sheath composite yarn of 56 decitex 24 filaments.

Table 1 shows the physical characteristics of the obtained fibers. The oxidative heat generation time of the obtained core-sheath composite yarn was 200 hours or more, and ΔYI = 0.5. Moreover, even after tumble drying, the texture, color tone, and moisture absorption performance were excellent.

[Example 2]
A core-sheath composite yarn of 56 decitex 24 filaments was obtained in the same manner as in Example 1 except that the core melted portion temperature was 235 ° C, the sheath melted portion temperature was 240 ° C, and the confluence melted portion temperature was 235 ° C. Table 1 shows the physical characteristics of the obtained fibers.

[Example 3]
A core-sheath composite yarn of 56 decitex 24 filaments was obtained in the same manner as in Example 1 except that the core melted portion temperature was 260 ° C., the sheath portion melted portion temperature was 280 ° C., and the merging portion fused portion temperature was 270 ° C. Table 1 shows the physical characteristics of the obtained fibers.

[Example 4]
Half-hindered phenolic antioxidants, 1,3,5-tris [[4- (1,1-dimethylethyl) -3-hydroxy-2,6-dimethylphenyl] methyl] -1,3,4- A core-sheath composite yarn of 56 decitex 24 filaments was obtained in the same manner as in Example 1 except that triazine-2,4,6 (1H, 3H, 5H) -trion (Cyanox1790 manufactured by Solvay) was used. Table 1 shows the physical characteristics of the obtained fibers.

[Example 5]
A core-sheath composite yarn of 56 decitex 24 filaments was prepared in the same manner as in Example 1 except that the amount of the half-hindered phenolic antioxidant added was adjusted to 1.0% by weight based on the weight of the core. Obtained. Table 1 shows the physical characteristics of the obtained fibers.

[Example 6]
A core-sheath composite yarn of 56 decitex 24 filaments was prepared in the same manner as in Example 1 except that the amount of the half-hindered phenolic antioxidant added was adjusted to 5.0% by weight with respect to the weight of the core. Obtained. Table 1 shows the physical characteristics of the obtained fibers.

[Example 7]
In addition to the addition of the half-hindered phenolic antioxidant (ADEKA ADEKA AO-80), the phosphorus stabilizer (BASF Irgafos 168) was added so as to be 2.0% by weight based on the weight of the core. A core-sheath composite yarn of 56 decitex 24 filaments was obtained in the same manner as in Example 1 except for the adjustment. Table 1 shows the physical characteristics of the obtained fibers.

[Example 8]
A core-sheath composite yarn of 56 decitex 24 filaments was obtained in the same manner as in Example 1 except that the core / sheath ratio (% by weight) was 50/50. Table 1 shows the physical characteristics of the obtained fibers.

[Comparative Example 1]
A core-sheath composite yarn of 56 decitex 24 filaments was obtained in the same manner as in Example 1 except that a half-hindered phenolic antioxidant was not added (no agent was added). Table 2 shows the physical characteristics of the obtained fibers. The obtained core-sheath composite yarn had an oxidative heat generation time of 0 hours, and oxidative heat generation was confirmed. In addition, in repeated tumble drying, the core component was oxidatively decomposed and denatured, and the texture and moisture absorption / desorption performance were deteriorated.

[Comparative Example 2]
Both hindered phenolic stabilizers (BASF's "Irganox" (registered trademark) 1010) are 2.0% by weight based on the weight of the core, and HALS stabilizers (BASF's CHIMASORB2020FDL) are added to the weight of the core. A core-sheath composite yarn of 56 decitex 24 filaments was obtained in the same manner as in Example 1 except that the content was adjusted to 2.0% by weight. Table 2 shows the physical characteristics of the obtained fibers. The obtained core-sheath composite yarn had ΔYI = 11.0, and yellowing was confirmed. In addition, the color tone changed drastically in repeated operations after tumble drying.

[Comparative Example 3]
Adjust the phosphorus-based stabilizer (BASF's Irgafos 168) to 2.0% by weight based on the weight of the core, and the HALS-based stabilizer (BASF's CHIMASORB2020FDL) to be 2.0% by weight based on the weight of the core. A core-sheath composite yarn of 56 decitex 24 filaments was obtained in the same manner as in Example 1 except for the above. Table 2 shows the physical characteristics of the obtained fibers. The oxidative heat generation time of the obtained core-sheath composite yarn was 0.5 hours, and oxidative heat generation was confirmed. In addition, in repeated tumble drying, the core component was oxidatively decomposed and denatured, and the texture and moisture absorption / desorption performance were deteriorated.

[Comparative Example 4]
A core-sheath composite yarn of 56 decitex 24 filaments was prepared in the same manner as in Example 1 except that both hindered phenolic stabilizers (Irganox 1010 manufactured by BASF) were adjusted to be 2.0% by weight based on the weight of the core. Got Table 2 shows the physical characteristics of the obtained fibers. The oxidative heat generation time of the obtained core-sheath composite yarn was 0.2 hours, ΔYI = 10.7, and oxidative heat generation and yellowing were confirmed. In addition, in repeated operations after tumble drying, the core component was oxidatively decomposed and denatured, the texture and moisture absorption / desorption performance deteriorated, and the color tone changed drastically.

[Reference example]
Add 194 parts of dimethyl terephthalic acid, 135 parts of ethylene glycol, 26.6 parts of dimethyl 5-sodium sulfoisophthalate (SSIA), 7.5 parts of trimethyl (TMTM) trimellitic acid and 0.1 part of tetrabutyl titanate, and add 140 to 140. After performing a transesterification reaction while distilling methanol at 230 ° C., 0.08 parts of trimethyl phosphate in an ethylene glycol solution and 328 parts of polyethylene glycol having a molecular weight of 4000, 0.2 parts of silicon as an antifoaming agent, and tetrabutyl titanate. 0.1 part was added, and polymerization was carried out under a reduced pressure of 1.0 mmHg at 250 ° C. for 4 hours to obtain a polyester copolymer. Using the same method as in Example 1, a master chip containing a high concentration of a half-hindered phenolic antioxidant (ADEKA, ADEKA STAB AO-80) and a polyester copolymer chip were prepared from this polyester copolymer. It was blended and adjusted to be 3.0% by weight based on the weight of the core. The copolymerized polyester thus adjusted was used as the core polymer, and the sheath polymer was changed to polyethylene terephthalate having an ultimate viscosity of 0.70. The core melt temperature was 260 ° C, the sheath melt temperature was 285 ° C, and the confluence melt temperature was 270. A core-sheath composite yarn of 56 decitex 24 filaments was obtained in the same manner as in Example 1 except that it was melted at ° C. The physical characteristics of the obtained fiber were strength 2.8 cN / dtex and elongation 47%. The obtained core-sheath composite yarn was obtained from (6) Oxidation heat generation test B. Since half-hindered phenol was inactivated by washing with water to which a bleaching agent was added as a pretreatment, the oxidative heat generation time was 0.2 hours, and oxidative heat generation was confirmed. In addition, B. of (6). The pre-treated fabric was deactivated by half-hindered phenol by washing with water after adding bleach, so the core component was oxidatively decomposed and denatured, and the texture was harder and stiffer than before the treatment, and the color tone was YI. It deteriorated sharply to 18.

1: High temperature dryer 2: Thermocouple 3: Cylindrical container 4: Sample

Claims

The sheath polymer is a polyamide and the core polymer is a polyether ester amide copolymer, and when heat-treated at 150 ° C., it takes 100 hours or more to start heat generation due to oxidative heat generation, and it dries at 70 ° C. for 8 hours. A core-sheath composite yarn characterized in that the change in yellowness (YI) (ΔYI) after heat treatment is 10 or less.
The core-sheath composite yarn according to claim 1, wherein the ΔMR is 5.0% or more, and the ΔMR retention rate after a dry heat treatment at 150 ° C. for 1 hour is 70% or more.
The core-sheath composite yarn according to claim 1 or 2, wherein the yellowness (YI) after dry heat treatment at 70 ° C. for 8 hours is 13 or less.
A fabric having at least a part of the core-sheath composite yarn according to any one of claims 1 to 3.