JP2006348411A - Crimped yarn consisting of sheath core conjugate fiber, and woven fabric using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a woven fabric consisting mainly of a biodegradable aliphatic polyester, aiming at the improvement of heat resistance and abrasion resistance, which can not be accomplished by conventional eccentric core type conjugate fibers, and a method for producing the same. <P>SOLUTION: This crimped yarn consisting of a sheath core type conjugate fiber having a core A formed by a thermoplastic polymer of an aliphatic polyester having ≤200°C melting point and a sheath part B formed by a thermoplastic polymer of a crystalline polyester having ≥200°C melting point is characterized in that the thickness eccentricity rate γ of the sheath part satisfies formula (1): γ=(b/a)=1 to 3 [wherein, (b): the maximum width between an outer circle and inner circle; (a): the minimum width between the outer circle and inner circle]. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention is an aliphatic polyester crimped yarn, a woven fabric comprising the same, and a method for producing the same.

  More specifically, the invention relates to a woven fabric composed of a crimped yarn of a core-sheath cross-sectional fiber in which the aliphatic polyester is used as a core, and excellent in heat resistance, wear resistance, stretchability, and wind resistance, and a method for producing the same. is there.

  In recent years, the development of fiber materials that can be decomposed in the natural environment has been eagerly desired. Among them, biodegradable fibers have been developed mainly with aliphatic polyesters such as polylactic acid.

However, when making a woven fabric using aliphatic polyester, particularly polylactic acid, as a general-purpose clothing fiber, there are some disadvantages compared to polyester and nylon fibers. Among these, it is pointed out that heat resistance and wear resistance are low as a large one. In order to compensate for these drawbacks, composite spinning with general-purpose polymers has been proposed. Although the purpose is different, Patent Document 1 describes an eccentric core-sheath type composite fiber of a polytrimethylene terephthalate component and a polylactic acid component. This is an eccentric core-sheath type composite form in which the polylactic acid forming the core is coated with the high melting point polytrimethylene terephthalate forming the sheath, resulting in better heat resistance than the conventional polylactic acid fiber. It has become a thing. However, it is a spiral crimped yarn that uses the difference in shrinkage between the core and sheath components, so it has the disadvantage that wrinkles and wrinkles are likely to occur and the dimensional stability is poor, as well as the part that becomes partially thin due to the eccentric structure Thus, the composite interface is easy to peel off, so that the coating strength is weak and a fabric having sufficient heat resistance and wear resistance cannot be obtained.
JP 2003-82530 A

The present invention provides a fabric having heat resistance and abrasion resistance, stretchability, and bulkiness, which could not be achieved by the above-described eccentric type composite fiber composed of the conventional biodegradable aliphatic polyester. It is a problem to obtain.

The object of the present invention can be achieved by adopting the following configuration. That is,
(1) A core-sheath composite fiber in which the thermoplastic polymer forming the core part A is an aliphatic polyester having a melting point of 200 ° C. or lower, and the thermoplastic polymer forming the sheath part B is a crystalline polyester having a melting point of 200 ° C. or higher. A crimped yarn comprising a sheath portion having an uneven thickness ratio γ satisfying the following formula (I):

(I) γ = b / a = 1-3 (b: maximum width of outer circle and inner circle)
a: Minimum width of outer circle and inner circle)
(2) The crimped yarn according to (1) above, wherein the aliphatic polyester forming the core A is polylactic acid.
(3) The crimped yarn according to (1) or (2) above, wherein the crystalline polyester forming the sheath portion B is polytrimethylene terephthalate.
(4) The crimped yarn according to any one of claims 1 to 3, wherein the expansion / contraction recovery rate (CR2) and the elongation elastic modulus satisfy the following formulas (II) and (III) simultaneously by false twisting: .

(II) 5 ≦ Retraction / retraction rate (CR2) ≦ 20
(III) Tensile modulus at 10% elongation ≧ 80%
(5) The crimped yarn according to any one of claims 1 to 5, wherein the total fineness is 33 to 170 dtex.
(6) A woven fabric using the crimped yarn according to any one of (1) to (4) as a warp yarn and / or a weft yarn.
(7) The total cover factor ratio (C · F) of warp and weft is 1700 to 3000, the stretch rate is 5 to 30%, the fastness to friction is grade 3 or higher (JIS standard), and the ventilation The fabric according to claim 6, wherein the degree is less than 1.0 cc / cm ² · S.
(8) The thermoplastic resin forming the core part A is composed of an aliphatic polyester having a melting point of 200 ° C. or less and the thermoplastic resin forming the sheath part B is made of a crystalline polyester having a melting point of 200 ° C. or more. The core-sheath composite fiber in which γ satisfies the following formula I is false twisted to obtain a crimped yarn whose stretch recovery rate (CR2) and elongation elastic modulus satisfy the following formulas II and III simultaneously. A method for producing a woven fabric, wherein the yarn is woven using warp and / or weft.

(I) γ = b / a = 1-3 (b: maximum width of outer circle and inner circle)
a: Minimum width of outer circle and inner circle)
(II) 5 ≦ Retraction / retraction rate (CR2) ≦ 20
(III) Tensile modulus at 10% elongation ≧ 80%

According to the present invention, by improving the heat resistance and wear resistance of the crimped yarn, it is possible to give excellent heat resistance, wear resistance and bulkiness to a product, and further, warping, weaving It is excellent in process passability in fabric making such as, and even a high-density woven fabric can impart stretch properties to the fabric.

Hereinafter, the best mode for carrying out the crimped yarn and the fabric of the present invention will be described in detail.
In the present invention, the crimped yarn is a core-sheath type composite fiber in which an aliphatic polyester having a melting point of 200 ° C. or lower forms a core A, and a sheath B is covered with a crystalline polyester having a melting point of 200 ° C. or higher. It is important to be.

The cross-sectional shape of the core-sheath type composite fiber may be a round cross section or any irregular cross section, and among them, the round, elliptical, and triangular cross sections shown in FIGS. 2 (a) to (c) are preferable. More preferably. In addition, the cross-sectional shape of the core is preferably a round shape such as a circle or an ellipse, and is most preferably a circle because the core is not easily exposed. In the core-sheath type crimped yarn of the present invention, the thickness ratio γ of the sheath portion based on the measurement method described later is a measured value representing the coating state of the core yarn, and the thickness ratio γ is expressed by the following formula (1). It is important to meet.
(1) γ = b / a = 1-3 (b: maximum width of outer circle and inner circle)
a: Minimum width of outer circle and inner circle)
Here, as shown in FIG. 2, the outer circle is an outline of the core-sheath type composite fiber, and the inner circle is a boundary line between the core portion and the sheath portion. The maximum width b of the outer circle and inner circle is the thickness of the thickest portion (thick skin) of the sheath, and the minimum width a of the outer circle and inner circle is the thinnest portion of the sheath (thin skin). In other words, it can also be referred to as the thickness. That is, the thickness ratio γ is 1 when the core and the sheath are completely circular with the same center.

  As described in the background art, the eccentric type composite fiber described in Patent Document 1 is superior in heat resistance and wear resistance to 100% polylactic acid, but the sheath part is partially thin due to the eccentric structure. And the part which becomes a thick skin has come out, Therefore, when false twisting, a partial non-uniform crimp will express. And when it is made into a fabric, there exists a fault that wrinkles and a wrinkle are easy to come out and dimensional stability is bad. Or, due to the eccentric structure, the film strength of the thin skin part is weak, and when receiving friction, the sheath part is torn, the undyed core part comes out, and the whitening phenomenon that the fabric is seen white also occurs Therefore, a fabric having sufficient heat resistance and wear resistance cannot be obtained, and it can be said that the practicality is poor.

  In the core-sheath type composite fiber in the present invention, the thickness deviation rate γ needs to be 1 to 3. Within this range, there is a sufficient film around the core yarn, the above-mentioned defects such as wrinkles and wrinkles can be improved, and the whitening phenomenon caused by the peeling of the core portion and the sheath portion can also be suppressed. And the high heat resistance and abrasion resistance which are applied to practical use are obtained. More preferably, higher heat resistance and wear resistance can be obtained as the uneven thickness ratio γ approaches 1, that is, when the thickness becomes concentric. On the other hand, if the uneven thickness ratio γ exceeds 3, a partially thick film (sheath part) cannot be obtained, and the resulting woven product has the desired high heat resistance and wear resistance. Not practical. The more preferable thickness ratio of the core-sheath type composite fiber is 1-2.

  The aliphatic polyester having a melting point of 200 ° C. or lower that forms the core A of the core-sheath type composite fiber refers to a thermoplastic polymer having an aliphatic alkyl chain linked by an ester bond and having a melting point of 200 ° C. or lower. Examples thereof include polylactic acid, polyhydroxybutyrate, polybutylene succinate, polyglycolic acid, polycaprolactone and the like. Among these, as described above, polylactic acid is preferable from the viewpoints of heat resistance, wear resistance, and production cost.

Moreover, components other than the main component may be copolymerized as long as the properties of the aliphatic polyester are not impaired. When using polylactic acid, it is preferable that the lactic acid monomer ratio in polylactic acid shall be 50 weight% or more from a viewpoint of biomass utilization and biodegradability. The lactic acid monomer is preferably 75% by weight or more, more preferably 96% by weight or more. Also, a thermoplastic polymer other than polylactic acid may be blended.
The aliphatic polyester may further contain additives such as particles, flame retardants, antistatic agents, antioxidants and ultraviolet absorbers as modifiers. The molecular weight should be sufficient to form a fiber. For example, in the case of polylactic acid, if the molecular weight is 50,000 to 350,000 in terms of weight average molecular weight, the balance between mechanical properties and moldability is preferable. It is more preferable that it is 100,000-250,000.

The manufacturing method of polylactic acid used for this invention can use a well-known method, and is not specifically limited. Specifically, the method disclosed in JP-A-6-65360 is exemplified. That is, a direct dehydration condensation method in which lactic acid is dehydrated and condensed as it is in the presence of an organic solvent and a catalyst. Further, it is a method of copolymerizing and transesterifying at least two kinds of homopolymers disclosed in JP-A-7-173266 in the presence of a polymerization catalyst. Furthermore, there is a method disclosed in US Pat. No. 2,703,316. That is, an indirect polymerization method in which lactic acid is once dehydrated to form a cyclic dimer and then subjected to ring-opening polymerization.
Since the melting point of polylactic acid is low as described in JP-A-6-65360, temperature limitations with irons and fusion during fabric processing are regarded as problems as fiber materials. However, other than that, due to the poor heat resistance of polylactic acid fiber, for example, the dimensional change when used in a temperature environment of Tg or higher, the fabric stretches in the sizing process, etc. However, it was a big problem that softening started early.

  In addition, polylactic acid has poor wear resistance and has a problem that it can be easily scraped by friction with a friction body. For this reason, there are restrictions on the business development for clothing and materials that presuppose friction. A fabric made of 100% polylactic acid has a very low friction fastness to dyeing (Gakushin-type friction test) of 1st grade, which is in comparison with general-purpose synthetic fibers such as PET and nylon (4th grade and above). It can be said that the level is so low that it does not become.

  In order to improve such heat resistance and wear resistance, the present invention has a configuration in which polylactic acid is used as a core portion and is covered with a sheath portion of crystalline polyester.

  The thermoplastic polymer that forms the sheath portion B of the core-sheath composite fiber needs to be a crystalline polyester having a melting point of 200 ° C. or higher. The crystalline polyester is, for example, a polyester composed of a dicarboxylic acid component and a glycol component, and an aromatic dicarboxylic acid component such as terephthalic acid, isophthalic acid, or phthalic acid can be used as the dicarboxylic acid component. As the glycol component, for example, ethylene glycol, 1,3-propylene glycol, 1,2-propylene glycol and the like can be used. These glycol components may be used alone or in combination of two or more. However, as described above, the melting point of the crystalline polyester is essential to be 200 ° C. or higher, and the melting point is preferably 205 to 260 ° C. in order to facilitate complex spinning with the core component. More preferably, it is 210-240 degreeC. Further, in order to improve wear resistance as well as heat resistance, polyethylene terephthalate (hereinafter referred to as PET), polytrimethylene terephthalate (hereinafter referred to as PTT), polybutylene terephthalate (hereinafter referred to as PET) among crystalline polyesters. It is preferable to use PBT). Among them, it is most preferable to use PTT because it is difficult to cause interface peeling with the aliphatic polyester forming the core and is excellent in durability against repeated bending. PTT has a property that it is difficult to store strain energy at the composite interface because it has excellent flexibility and elongation recovery in the longitudinal direction of the fiber. Furthermore, it is easy to impart high stretchability and bulkiness by false twisting, and since it can be dyed at low temperature, it has the advantage that it can be dyed without damaging aliphatic polyester that is generally easily hydrolyzed. .

  The crystalline polyester may be a homopolymer, but it is also preferable to blend an elastomer or a copolymerized polymer in order to impart flexibility to the polymer. Furthermore, you may contain additives, such as particle | grains, a flame retardant, an antistatic agent, an antioxidant, and an ultraviolet absorber.

The core-sheath type composite fiber in the present invention has high heat resistance when the core part A is 80% or less in the core-sheath composite ratio (weight ratio). There is a clear correlation between the ratio of the aliphatic polyester in the core and the heat resistance. If the ratio is small, the heat resistance is improved. On the other hand, the lower limit of the core part A is not particularly limited, but 50% or more is preferable in that the characteristics of the aliphatic polyester are not impaired.
The crimped yarn of the present invention is preferably a multifilament having a total fineness of 33 to 170 dtex. When the total fineness is less than 33 dtex, quality problems such as generation of fluff are liable to occur when the woven fabric is used. On the other hand, when the total fineness exceeds 170 dtex, the desired soft woven fabric cannot be obtained. A more preferable total fineness is 60 to 120 dtex.

  The crimped yarn of the present invention is preferably a multifilament having a single fiber fineness of 1 to 5 dtex. If the single fiber fineness is less than 1 dtex, the accuracy of each single fiber is lowered, so that a quality problem is likely to occur. On the other hand, if the single fiber fineness is larger than 5, a desired woven fabric with a soft feeling cannot be obtained. A more preferable total fineness is 2 to 4 dtex.

  Further, the core-sheath type composite fiber in the present invention is preferably subjected to yarn processing such as false twist. For false twisting, a known false twisting method can be used, and among them, a belt nip type friction false twist tool can be preferably used.

  Next, a preferred false twisting method will be described with reference to FIG. Various guides, tension control devices, fluid processing devices, oil supply devices, and the like may be arranged in the device of FIG. 1 as necessary.

  It is preferable that the temperature of the 1st heater 4 is the range of 90-150 degreeC. When the temperature of the first heater is 90 ° C. or higher, the obtained crimped yarn can be heat-set, and the following formula (2) crimp characteristics (CR2) and (3) excellent in both elastic modulus can get. On the other hand, when the temperature is set to 150 ° C. or lower, a crimped yarn having good mechanical characteristics and quality can be obtained without causing softening of the yarn on the first heater or reduction in strength. The temperature of the first heater 4 is more preferably 100 to 145 ° C for the above reasons, and even more preferably 110 to 140 ° C.

  Further, it is more preferable that the first heater 4 is a non-contact type because yarn breakage due to scratch resistance can be suppressed. When a non-contact heater is used for the first heater 4, the heater temperature is preferably 150 to 350 ° C. By setting the temperature of the first heater 4 to 150 ° C. or higher, the crimp characteristics (CR2) and the elongation elastic modulus of the crimped yarn of the present invention can be satisfied at the same time. On the other hand, by setting it to 350 ° C. or lower, false twisting can be performed stably without breaking the yarn. Therefore, in the case of the non-contact type, the heater temperature is more preferably 160 to 330 ° C, and further preferably 170 to 300 ° C.

  Moreover, it is preferable that the speed ratio of the supply roller 2 and the drawing roller 7 in the false twisting process, that is, the processing magnification is 1.1 to 1.8 times. When the processing magnification is 1.1 times or more, the twisting tension (T1) in false twisting is increased, and a high twist number is given to the yarn in the first heater 4, so that the crimping property (CR2) is excellent. It becomes a crimped yarn. Further, by setting the processing magnification to 1.8 times or less, stable false twisting can be performed, and a crimped yarn excellent in quality with less fluff can be obtained. The processing magnification is more preferably 1.15 to 1.7 times, still more preferably 1.2 to 1.6 times.

  Further, in applications where a low heat shrinkage rate (SW) is required in a high-order process, it is necessary to provide the second heater 8 as described above. At this time, it is preferable that the temperature of the 2nd heater 8 is 80-140 degreeC.

  The boiling water shrinkage (SW) of the crimped yarn can be controlled by setting the temperature of the second heater 8 and an overfeed rate (hereinafter referred to as OF rate 2) described later. Is less than 80 ° C., the effect is small. Moreover, by making it 140 degrees C or less, it can process stably without a thread break. At the same time, the residual torque can be kept low by optimizing the temperature of the second heater and the OF ratio 2. The temperature of the second heater is more preferably 90 to 130 ° C, and further preferably 95 to 120 ° C.

  Further, the OF ratio 2 obtained from the following formula is preferably 10 to 30%.

OF ratio 2 (%) = (V2-V3) / V2 × 100
V2: peripheral speed of the feed roller 7 V3: peripheral speed of the take-up roller 9 If the OF ratio 2 is 10% or more, the thermal shrinkage rate (SW) of the crimped yarn obtained is reduced and the dimensional stability is improved. In addition, the residual torque can be reduced, and the delayed recovery rate of the wound crimped yarn can be reduced. On the other hand, if the OF ratio 2 is 30% or less, yarn breakage and fusion between single fibers due to contact with the heater can be prevented, and the running stability of the yarn can be improved. The OF ratio 2 is more preferably 12 to 25%, and further preferably 15 to 20%.

  The ratio of the peripheral speed (D) of the twisted body 6 and the speed (Y) of the feed roller 7 (hereinafter referred to as D / Y) is preferably in the range of 1.1 to 2.0. By setting D / Y to 1.1 or more, the twisting tension and the untwisting tension are well balanced, and false twisting without fuzz and yarn breakage can be performed. Further, by setting D / Y to 2.0 or less, the surface wear of the twisted body 6 is suppressed, and there is no unevenness in the longitudinal direction of the yarn even in continuous operation for several hundred hours. Untwisted false twisting is possible. D / Y is more preferably 1.15 to 1.8, and still more preferably 1.2 to 1.7.

  In the method for producing a crimped yarn of the present invention, the overfeed rate (hereinafter referred to as OF rate 2) of the delivery roller 7 needs to be appropriately optimized by setting the OF rate 1. When the second heater is not used and the relaxation heat treatment is not performed, the OF ratio 2 needs to be set high, and is preferably approximately 10 to 35%. Further, when the relaxation heat treatment is performed using the second heater, the OF ratio 2 is preferably 0 to 25%. The OF ratio of 2 is sufficient if the yarn can be wound stably without loosening between the delivery roller 26 and the cheese 29 so that the yarn tension is 0.02 to 0.10 cN / dtex. By winding, the delayed recovery rate of the wound yarn can be reduced, and the difference between the inner and outer layers of the physical properties of the fiber due to tightening can be reduced. In addition, the saddle and bulge are suppressed, and a package with a good winding shape can be obtained.

  The crimped yarn obtained by the above-described method is used for process passage in a higher order process, for example, when used for weaving and knitting, in order to suppress rubbing between fibers and yarn path guides, knitting needles, etc. Preferably it is done. As the oil to be applied, it is preferable to use an oil containing a smoothing agent having a high effect of reducing the coefficient of friction between the fibers and the metal. For example, fatty acid ester, polyhydric alcohol ester, ether ester, silicone, mineral oil and the like are preferable.

The crimped yarn obtained by the above-described method is a crimped yarn in which the expansion / contraction recovery rate (CR2) and the elongation elastic modulus satisfy the following expressions (2) and (3) at the same time.
(2) 5 ≦ Retraction / retraction rate (CR2) ≦ 20
(3) Tensile modulus at 10% elongation ≧ 80%
PTT is preferably used for the sheath portion of the core-sheath type composite fiber in the present invention, but PTT has the property that the main chain of the methylene group expands and contracts, and therefore has excellent stretch recovery properties in the fiber longitudinal direction. Since conventional PET crimped yarns are tightly constrained when made into a woven fabric, the original stretchability cannot be expressed. A method of measuring the stretchability of the crimped yarn in the restrained state is the stretch recovery rate (CR2) taken up in the present invention.

  The crimped yarn of the present invention preferably has an expansion / contraction recovery rate (CR2) of 5 to 20% based on a measurement method described later. By using a false twisted yarn having an expansion / contraction restoration rate (CR2) of 5% or more, a product having high bulkiness and stretchability when made into a woven fabric can be obtained. On the other hand, if the expansion / contraction recovery rate (CR2) exceeds 20%, the texture is coarsely cured and the surface quality tends to deteriorate when it is made into a woven fabric. Therefore, in order to impart bulkiness and stretchability as a processed yarn while giving a high-quality fabric surface when made into a woven fabric, the stretch / restore rate (CR2) is preferably 10 to 15%. In addition, the expansion-contraction recovery rate (CR2) in this invention says the value measured with the measuring method mentioned later.

  Further, in the present invention, the elongation elastic modulus at 10% elongation was taken up in order to evaluate the excellent stretch recovery property of the crimped yarn. The elongation modulus based on the measurement method described later is preferably 80% or more when stretched at 10%, and more than 70% when stretched at 20%, or stretch elasticity when stretched at 30%. The rate is preferably 60% or more. By setting it as this range, when making it into a woven fabric, even if yarns are closely restrained, the highly practical stretch property can be provided. In addition, the expansion | extension elastic modulus in this invention means the value measured with the measuring method mentioned later.

  Next, a fabric using the crimped yarn of the present invention will be described.

  The woven fabric of the present invention is a woven fabric using the crimped yarn of the present invention as warp yarn and / or weft yarn. A flat woven fabric (1/1 flat or piece mat, etc.) having a large force is desirable. In addition, by adopting the crimped yarn of the present invention, when it is made into a woven fabric, the effect of reducing the gap generated between the crossing point of the woven fabric where the warp yarn and the horizontal yarn intersect and the adjacent crossing point is improved, Windproof and water repellency is improved.

Next, in the woven fabric of the present invention, in order to obtain a woven fabric excellent in windproof property, the total coverage of the warp yarn and the weft yarn constituting the woven fabric is 1700 or more and 3000 or less, and the ventilation of the fabric. The degree is preferably less than 1.0 cc / cm ² · s. The total coverage and air permeability can be achieved by setting the yarn density of the woven fabric, for example, the warp density to 120 to 180 / 2.54 cm and the transverse density to 100 to 160 / 2.54 cm.

The total coverage of warp and weft is a factor that represents the fineness of the warp and weft that make up the fabric. If the total coverage is less than 1700, windproof and water repellency will not be sufficient. A woven fabric having a total coverage exceeding 3000 is not preferable because it is a region that cannot be stably obtained in industrial production. A more preferable range of the total coverage is 2000 or more and 3000 or less. The total coverage referred to here is calculated by the following equation.
Total cover rate = Warp yarn cover rate + Weft yarn cover rate Warp yarn cover rate = Warp yarn density (line / 2.54cm) x (Wait yarn fineness (dtex)) ^1/2
Cover rate of weft yarn = weft yarn density (main / 2.54cm) x (weft yarn fineness (dtex)) ^1/2
The air permeability is a measured value representing the windproof and water repellency performances of the present invention, and the air permeability of the fabric of the present invention is preferably less than 1.0 cc / cm ² · s, more preferably Is less than 0.8 cc / cm ² · s. Such air permeability is a characteristic necessary for exerting functionality when a high-density fabric is used as clothing. This air permeability can be obtained relatively easily by applying a high-temperature and high-pressure press, which is usually called “calendar” processing, when producing a fabric. Further, a method of thinly coating the surface of the fabric with a polyurethane resin can be employed as a means for reducing the air permeability.

  The air permeability here represents windproof and water-repellent performance, but the secondary performance is that the fabric is dense, so the pollen can be applied as it is or with a light water-repellent finish. Therefore, it can be used for antiallergic clothing such as hay fever.

  The woven fabric made of the crimped yarn of the present invention is high in fabric even if it is a high-density woven fabric due to the elastic properties of PTT that the main chain of the methylene group expands and contracts when PTT is used for the crimped yarn. Stretch properties can be imparted. That is, the conventional PET crimped yarn can also have the above-described expansion / contraction elongation ratio, but when it is made into a woven fabric, if it is tightly restrained, the original stretchability cannot be expressed. By making the crimped yarn having such a core-sheath structure into a woven fabric, it is possible to have a high stretch property that is difficult to obtain normally. In addition, the stretch property of the fabric in the present invention refers to a value measured by a measurement method described later.

  In addition, the woven fabric made of the crimped yarn of the present invention can satisfy a practical level in various dyeing fastness tests determined by JIS. For example, when the woven fabric is used for general clothing, the dyeing fastness to washing (JIS-L0844) and the fastness to dyeing with respect to ultraviolet carbon arc lamp (JIS-L0842) are required to be higher than the third grade. These values are satisfied.

  As for the wear resistance which is the object of the present invention, it is preferable that both dryness and wetness are grade 3 or higher in the friction tester type II (Gakushin type) of the dyeing fastness test for friction (JIS-L0849). It is more preferable that both the dryness and the wetness are quaternary or higher, but the woven fabric of the present invention satisfies these values. In addition, when the dyeing fastness test is carried out on a fabric made of 100% polylactic acid, the dyeing fastness to rubbing against the friction is very bad at the first grade for both dryness and wetness, although it passes the third grade in the washing and light resistance test.

  Moreover, also about the high temperature mechanical characteristic which is a problem with polylactic acid, since the PTT was provided to the sheath part, the crimped yarn of the present invention has excellent strength characteristics even under heating. In the present invention, the strength under heating at 90 ° C. is preferably 0.8 cN / dtex or more, and more preferably 1 cN / dtex. By the way, the strength of the fiber using 100% polylactic acid when heated at 90 ° C. is 0.3 cN / dtex at most.

Furthermore, when finishing the fabric, a calendering process is indispensable, and the required temperature is 140 ° C. or higher. In a 100% polylactic acid woven fabric, the heat resistance is at most about 120 ° C., and beyond that, the fibers soften and flatten, and glossy spots called “around” are generated. Further, when the temperature is set to 140 ° C., a hole is formed due to partial melting, or a cloth having a strong feeling of coarseness is obtained, which is no longer practical. For this reason, a practically woven fabric cannot be obtained by using 100% polylactic acid fiber. On the other hand, the woven fabric made of the crimped yarn of the present invention has a heat resistance of 160 ° C. or higher, and the fiber is not softened or deformed even in the calendering process.
Next, the manufacturing method of the textile fabric of the present invention will be described.
In order to manufacture the core-sheath type composite fiber used in the fabric of the present invention, it can be basically manufactured using a known melt composite spinning apparatus.

  First, an aliphatic polyester having a melting point of 200 ° C. or lower that forms the core A and a crystalline polyester having a melting point of 200 ° C. or higher that forms the sheath B are selected from the polymers described above. For example, poly-L lactic acid (melting point: 170 ° C.) having an optical purity of 97% is used for the core part A, and PTT (melting point: 228 ° C.) is used for the sheath part B. These polymers are individually melted and weighed, and the fibers are spun from an apparatus of a composite spinneret in which aliphatic polyester B is disposed on the fiber surface. After cooling, the oil is applied and wound. The eccentricity γ is appropriately set according to the shape of the composite spinneret so that the eccentricity γ is 1 to 3.

The melt spinning described above is capable of low speed spinning at a winding speed of 1000 to 2000 m / min, high speed spinning at a winding speed of 2000 to 5000 m / min, and ultra-high speed spinning at a winding speed of 5000 m / min or more. A so-called spin draw method in which stretching is continuously performed can also be preferably applied.
When the thickness ratio γ is high in the obtained core-sheath type composite fiber, due to the difference in thermal contraction rate between the core polymer and the sheath polymer, the thick part of the sheath part is reduced when heat treatment is performed. It has a crimped form that is inside.

When weaving a woven fabric with the crimped yarn of the present invention thus produced, it can be woven by a known weaving method using a known weaving machine such as a rapier loom, a water loom, an air jet loom or the like.
The crimped yarn of the present invention thus produced is also applied to knitting. As for the knitted fabric, the effect of the crimped yarn can be exerted in either a normal round knitting or warp knitting.

  In dyeing, it is preferable to use a softer relaxation or a liquid flow relaxation method as a relaxation scouring process in order to increase the density.

  The woven fabric of the present invention has heat resistance and abrasion resistance excellent in practicality, and also sportswear and casual wear that make use of windproof and water repellency, and outer or lining materials such as down jackets and batting jackets that make use of high density It was used suitably for etc.

  Hereinafter, the present invention will be described in detail with reference to examples. In addition, each characteristic value in an Example was calculated | required with the following method.

A. Uneven thickness ratio γ
γ = b / a = 1-3 (b: maximum width of outer circle and inner circle)
a: Minimum width of outer circle and inner circle)
The crimped yarn is fixed with an embedding material, the section is cut out, and after the de-embedding, the cross-section is enlarged with an optical microscope and photographed, and the monofilament cross-section as shown in FIG. The distance between b and a is measured, and one γ ₁ is obtained. Similarly, the measurement is performed 10 times at random, and the average value γ is obtained. Γ was obtained up to one decimal place.

B. Expansion / contraction recovery rate (CR2)
The crimped yarn was scraped, applied with an initial load of 0.0018 cN / dtex (2 mgf / d), treated in 90 ° C. water for 20 minutes, and air-dried for 24 hours. Next, an initial load of the same weight was applied in water at room temperature (25 ° C.), and the length L1 after 2 minutes was measured. Next, in room temperature water (25 ° C.), except the initial load of 0.0018 cN / dtex, replace with a load equivalent to 0.09 cN / dtex (0.1 gf / d), and measure the skein length L0 after 2 minutes. did. And CR2 value was calculated by the following formula.

CR2 (%) = [(L0−L1) / L0] × 100 (%)
C. Elastic modulus of elasticity Measured according to JIS L1018 (Method A).

D. Expansion / contraction recovery rate (CR)
CR (%) = [(L2-L3) / L2] × 100 (%)
L3: The length of the casserole in a load-free state in 90 ° C. water for 20 minutes, air-dried for 24 hours, and then in water under an initial load of 0.0018 cN / dtex.

  L2: A casserole length measured after 2 minutes after replacing the initial load of 0.0018 cN / dtex in water with a load equivalent to 0.09 cN / dtex (0.1 gf / d).

E. Boiling water shrinkage (SW)
Boiling water shrinkage rate (%) = [(L4-L5) / L4] × 100 (%)
L4: Original length measured with an initial load of 0.09 cN / dtex after removing the sample.

  L5: Case length under load 0.09 cN / dtex after treating L4 measured in boiling water in boiling water for 20 minutes and air drying for 24 hours.

F. Stretch elongation rate In accordance with JIS L1090 synthetic fiber filament bulk processing thread test method (1998), Section 5.7 C method (simple method), the stretch elongation rate and the stretch elastic modulus were defined by the following formulas.

Expansion and contraction rate (%) = [(L7−L6) / L6] × 100%
Elastic modulus of elasticity (%) = [(L7−L8) / (L7−L6)] × 100%
L6: Length of casket after hot water treatment at 90 ° C. for 20 minutes with a 0.0018 cN / dtex load suspended from a fiber casserole, and air-drying for one day.

  L7: Lase length after 30 seconds after removing L6 measurement load and hanging 0.09 cN / dtex load after L06 measurement.

  L8: Lase length after 30 seconds after removing L7 measurement load and leaving it to stand for 2 minutes after hanging L7 load again with 0.0018 cN / dtex load.

G. Residual torque The upper ends of both ends are 0.059 cN / dtex so that the crimped yarn is bent into a V shape with a ceramic rod guide as a fulcrum so that no untwisting and untwisting occur. Fix under load of. A fine load of 0.003 cN / dtex is applied to the sample portion of the rod guide, the sample is removed from the rod guide, and the sample is rotated in a suspended state. When the turning stopped, the twisting was carried out with a twisting machine and the number of turns was measured. The residual torque per 1 m of sample was calculated | required by making the frequency | count of a test 5 times and doubling the average value.

H. Dyeing fastness test The obtained dyed fabric was subjected to class judgment according to dyeing fastness to washing JIS L0844 (1998) and dyeing fastness test to carbon arc lamp JIS L0842 (1998).

I. Dye fastness test against friction The dyed fabric obtained is treated using a friction tester type II (Gakushin type) in accordance with JIS L0849 (1998), and the grade is determined in five stages for each of the dry test and the wet test. went.

J. Iron heat resistance test A sample of approximately 84 dtex was woven as a warp and weft into a plain woven fabric at a weaving density of 110 × 90 pieces / 2.54 cm, set in a living machine with a 140 ° C. tenter, and then scoured to obtain a woven fabric. After dyeing this fabric at 110 ° C. × 60 minutes with 1% owf concentration of the disperse dye DianixBlack BG-FS200, Granup INA-5 (manufactured by Sanyo Kasei) and 80 ° C. × 20 at a concentration of 0.5 g / liter sodium carbonate A part soaping process was performed, and a finishing set was performed at 130 ° C.

About the obtained dyed cloth, using a steam iron A-1F manufactured by Sanyo Electric Co., Ltd., when the iron surface temperature reaches a predetermined temperature, the cloth is pressed with the iron's own weight (surface pressure of about 8 g / cm ² ) for 10 seconds. The appearance change after pressing was evaluated.

  “No change” is “XX”, “Slightly attrition” is “O”, “Clear atariment” is “△”, “Partial fusion between fibers” is “X”, “ “Perforation by melting” was defined as “XX”.

K. Air permeability Measured according to JIS L1096 (Method A).

L. Strength and elongation Measured according to the chemical fiber filament yarn test method (1998) of JIS L1013. Note that a load-elongation curve was obtained with a gripping interval of 200 mm and a tensile speed of 200 mm / min. Next, the load value at the time of breaking was divided by the initial fineness, which was taken as the strength, the elongation at the time of breaking was divided by the initial sample length, and the strength and elongation were obtained as the elongation. The measurement was carried out at room temperature (25 ° C.).

M. Stretchability Measured according to JIS L1096 (Method A).
In addition, the evaluation in an Example was performed with the following method.

N. Wrinkle / Wrinkle Defect Judgment The wrinkle / wrinkle defects of the fabrics obtained by the methods described in Examples and Comparative Examples were subjected to sensory evaluation by appearance. At this time, with the defect and texture of the woven fabric of Comparative Example 2 as the standard (the following x mark), a four-step evaluation was performed based on the following criteria, and the evaluation results of the 10 panelists were averaged for determination.
○○: Wrinkles and wrinkles are not completely observed.
○: Some wrinkles and wrinkles are observed, but the texture is not affected.
Δ: Wrinkles and wrinkles are observed, and the texture is slightly affected.
X: Wrinkles and wrinkles are observed, and the surface of the fabric is disturbed.

O. Whitening Phenomenon Determination The whitening phenomenon of the fabrics obtained by the methods described in Examples and Comparative Examples was sensory-evaluated by appearance. At this time, with the woven fabric phenomenon and texture of Comparative Example 2 as the standard (the following x mark), a three-stage evaluation was performed according to the following criteria, and the evaluation results of the 10 panelists were averaged and determined.
○: The whitening phenomenon is not completely observed.
Δ: Some whitening phenomenon is observed, but the texture is not affected.
X: A whitening phenomenon is observed and the texture is affected.

Example 1
A polycarbodiimide "carbodilite" HMV-8CA manufactured by Nisshinbo Co., Ltd. as a compatibilizer in poly L lactic acid (optical purity 97% L lactic acid) having a weight average molecular weight of 16,000, a melting point of 170 ° C. and a residual lactide amount of 0.085% by weight. 1% by weight of PTT (melting point 228 ° C.) having an intrinsic viscosity [η] of 0.92 containing 0.3% by weight of titanium oxide having an average secondary particle size of 0.4 μm. As the sheath, a core-sheath composite ratio (weight ratio) of 70/30 is used in a composite composite machine using a concentric core-sheath composite base having a spinning temperature of 250 ° C. and a spout hole diameter of 0.25 mm / hole depth of 0.75 mm. And was further wound up at a take-up speed of 3000 m / min to obtain an undrawn yarn having a core-sheath composite structure of 105 dtex-36f.

  Further, the undrawn yarn was drawn simultaneously using a false false twisting machine provided at the belt nip shown in FIG. 1, the processing speed was 400 m / min, the processing magnification was 1.4 times, the first heater temperature was 120 ° C., and the D / Y ratio was 1. .3, followed by a relaxation heat treatment at a second heater temperature of 110 ° C. and a reset rate of 24%, and wound up 84 decitex, 36 filament crimped yarn with an OF rate of 15% at the delivery roller exit. . The yarn threading property and process passability were good, and yarn breakage did not occur.

  Table 1 shows the results of evaluating the properties of the obtained crimped yarn. The elastic recovery rate (CR2) showing the crimping property is 15%, the elongation elastic modulus showing the elongation recovery property is 90% (at 10% elongation), and the false twisted yarn with good mechanical properties and crimp properties (捲(Reduced yarn) was obtained. The cross-sectional shape of the obtained yarn is the circular shape shown in FIG. 2, and the uneven thickness ratio γ is 1.1.

  The false twisted yarn has a strength of 2.5 cN / dtex, an expansion / contraction recovery ratio (CR) of 30%, an expansion / contraction elongation ratio of 50%, and a residual torque of 75 T / m. It had high bulkiness, elasticity, and form stability.

Further, using the false twisted yarn for warp and weft, weaving a plain woven fabric having a warp density of 120 (lines / 2.54 cm) and a weft density of 89 (lines / 2.54 cm), followed by 98 ° C. Relaxed with warm water, intermediate set at 140 ° C., dyed at 110 ° C. wet heat, and finished set at 140 ° C. dry heat. The resulting woven fabric has a warp yarn density of 135 (lines / 2.54 cm), a weft yarn density of 94 (lines / 2.54 cm), and has a high windproof property of 1.0 cc / cm ² · s, and Iron heat resistance has no surface change even at 200 ° C., shows extremely good heat resistance, and has 4 grades for both dryness and wetness in the dyeing fastness test against friction, and extremely excellent heat resistance and wear resistance. I had it. At this time, the cover rate of the warp yarn was 1237, the cover rate of the weft yarn was 861, and the total cover rate was 2100. Table 1 shows the results of evaluation of the obtained fabric characteristics.

  As described above, Example 1 shows the mechanical properties of the crimped yarn and the heat resistance and wear resistance of the fabric sufficiently with practical use, and this is also shown in the sensory evaluation of wrinkles, wrinkles and whitening phenomenon. In addition, since the improvement of the defects that occurred in the prior art was confirmed, it was found that it can be suitably used for clothing.

Example 2
Evaluation was made in the same manner as in Example 1 except that the core-sheath composite ratio was 80/20 and the thickness ratio γ was 1.2. In Example 2 in which the composite ratio of the sheath is 20%, the iron heat resistance does not change up to 180 ° C., and the fastness to dyeing with respect to friction is dry grade 3 and wet grade 4 with sufficient heat resistance and wear resistance to withstand practical use. Indicated. However, the stretch recovery rate (CR2) indicating the crimp characteristics of the yarn is 11%, the stretch elastic modulus exhibiting the stretch recovery property is 83% (when stretched by 10%), which is slightly less than that of Example 1, and therefore the fabric. When stretched, the stretchability is 20%, which is less than Example 1, but it can also be said to be a good stretchability.

Example 3
Evaluation was made in the same manner as in Example 1 except that the die was made into an eccentric core-sheath type (both core and sheath had a round cross section) and the thickness ratio γ was set to 2.0. The expansion / contraction recovery rate (CR2) showing the crimping property of the yarn and the extension elastic modulus showing the extension recovery property are almost the same as in Example 2. Further, even in the case of the fabric, the iron heat resistance and the fastness to dyeing with respect to friction were the same as those in Example 2, and exhibited high heat resistance and wear resistance sufficiently suitable for practical use.

Example 4
In Example 4, the same polylactic acid as in Example 1 was used as the core component, and polyethylene terephthalate having a limiting viscosity [η] of 0.56 copolymerized with 4.5 mol% of 5-sodiumsulfoisophthalate was used as the sheath component. Core-sheath composite ratio (weight ratio) 70 / in a composite composite machine using a concentric core-sheath composite base with a spout temperature of 250 ° C. similar to 1 and an outlet hole diameter of 0.25 mm / hole depth of 0.75 mm. 30, and further wound up at a take-up speed of 3000 m / min to obtain an undrawn yarn having a core-sheath composite structure of 105 dtex-36f. The obtained drawn yarn was woven and processed in the same manner as in Example 1. A woven fabric was obtained. Table 1 shows the evaluation results of physical properties and fabrics. It showed high heat resistance and wear resistance suitable for practical use, but the elastic recovery (CR2), which shows the crimp characteristics of the yarn, was 4%, and the elastic modulus, which shows the elongation recovery, was also 50% (at 10% elongation) ), The stretchability when made into a woven fabric was 9%, and the stretchability was inferior compared to Examples 1-3.

Comparative Example 1
Evaluation was made in the same manner as in Example 1 except that the die was an eccentric type (both core and sheath had a round cross section) and the thickness ratio γ was 4.0. In Comparative Example 1, both spinnability and stretchability are good, and the strength is also good, but the crimp property is almost the same as in Example 1, so that the stretchability when made into a woven fabric reaches 20%. Yes. However, it was confirmed that the iron heat resistance did not change up to 160 ° C., and partial fusion occurred at 180 ° C., resulting in a strong texture. The dyeing fastness to friction is dry grade 3 and wet grade 3, and sensory evaluation of wrinkles, wrinkles and whitening phenomenon has confirmed these disadvantages, and it proved to be slightly impractical. did.

Comparative Example 2
Evaluation was made in the same manner as in Example 1 except that the die was an eccentric type (both core and sheath had a round cross section) and the thickness ratio γ was 6.0. The cross-sectional shape of the obtained yarn is the shape shown in FIG. In Comparative Example 2, the strength and the like were good, but in the iron heat resistance test, a partial fusion occurred at 160 ° C., giving a strong texture, and at 180 ° C., it melted and opened a hole. The dyeing fastness to friction was grade 2 for both dry and wet, and was impractical.

It is the schematic diagram which showed one embodiment of the extending | stretching simultaneous false twisting machine used by this invention. (A)-(c) is a figure which shows the cross-sectional shape of one embodiment of the core-sheath conjugate fiber of this invention.

Explanation of symbols

1: Undrawn yarn package 2: Feed roller 3: Yarn guide 4: First heater 5: Cooling plate 6: Friction false twist belt unit 7: Feed roller 8: Second heater 9: Delivery roller 10: Winding roller 11: drawn false twisted yarn package 12: sheath component 13: core component

Claims (8)

The thermoplastic polymer that forms the core part A is an aliphatic polyester having a melting point of 200 ° C. or lower, and the thermoplastic polymer that forms the sheath part B is a core-sheath composite fiber that is a crystalline polyester having a melting point of 200 ° C. or higher. A crimped yarn, characterized in that the thickness ratio γ of the sheath satisfies the following formula (1).
(1) γ = b / a = 1-3 (b: maximum width of outer circle and inner circle)
a: Minimum width of outer circle and inner circle) 2. The crimped yarn according to claim 1, wherein the aliphatic polyester forming the core A is polylactic acid. The crimped yarn according to claim 1 or 2, wherein the crystalline polyester forming the sheath portion B is polytrimethylene terephthalate. The crimped yarn according to any one of claims 1 to 3, wherein the expansion / contraction recovery rate (CR2) and the elongation elastic modulus satisfy the following formulas (2) and (3) simultaneously by false twisting.
(2) 5 ≦ Retraction / retraction rate (CR2) ≦ 20
(3) Tensile modulus at 10% elongation ≧ 80% The crimped yarn according to any one of claims 1 to 4, wherein the total fineness is 33 to 170 dtex. A woven fabric using the crimped yarn according to any one of claims 1 to 5 for warp and / or weft. The total cover factor ratio (C · F) of warp and weft is 1700 to 3000, the stretch rate is 5 to 30%, the fastness to friction is 3 or more (JIS standard), and the air permeability is 1 The woven fabric according to claim 6, which is less than 0.0 cc / cm ² · S. The thermoplastic resin forming the core part A is made of an aliphatic polyester having a melting point of 200 ° C. or less and the thermoplastic resin forming the sheath part B is made of a crystalline polyester having a melting point of 200 ° C. or more. The core-sheath composite fiber satisfying the formula (1) is false twisted to obtain a crimped yarn whose expansion / contraction recovery rate (CR2) and elongation elastic modulus satisfy the following formulas (2) and (3) simultaneously: A method for producing a woven fabric, wherein the crimped yarn is woven using warp yarn and / or weft yarn.
(1) γ = b / a = 1-3 (b: maximum width of outer circle and inner circle)
a: Minimum width of outer circle and inner circle)
(2) 5 ≦ Retraction / retraction rate (CR2) ≦ 20
(3) Tensile modulus at 10% elongation ≧ 80%

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