JP5774820B2 - Variety of different sizes - Google Patents

Description

  The present invention relates to a yarn composed of fibers including a specific component and having a specific structure.

  Conventional sports clothing such as winter clothing, skiing, mountain climbing, etc. often used clothing with a three-layer structure using batting. Such clothing is composed of three layers, surface layer, batting and lining, and the air insulation layer is made by batting to enhance the heat retaining performance, but the clothing composed of three layers is heavy and lacks sportiness was there.

In addition, a heat retaining fabric in which a metal such as aluminum or chromium is coated on a woven or knitted fabric is also known. However, when such a fabric is used as a garment, there is a problem in that the performance of the fabric due to the coating is deteriorated and various performances are deteriorated due to repeated use.
In order to solve such a problem, for example, in Patent Document 1, the core component is polyethylene terephthalate containing 2.5% by mass of zirconium silicide having an average particle diameter of 0.8 μm as the core component and polyethylene terephthalate as the sheath component. A core-sheath type composite fiber having a single yarn fineness of 2.8 dtex by composite melt spinning with / sheath = 6/4 has been proposed.
Further, Patent Document 2 proposes a composite fiber which is also a core-sheath type composite fiber, and the cross-sectional shape of the core part including the infrared fine particles has an irregular cross-sectional shape having 5 to 30 protrusions. .

JP-A-5-9804 JP 2009-41137 A

In the composite fiber described in Patent Document 1, the zirconium silicide contained in the core part absorbs infrared rays, so that the woven or knitted fabric exhibits a heat retaining effect. However, since this conjugate fiber has a concentric core-sheath structure, the surface area of the core portion containing zirconium silicide is small, and as a result, the infrared absorption efficiency is poor, and the woven or knitted fabric using the conjugate fiber is satisfactory. There is a problem that the thermal insulation effect of the level cannot be exhibited.
Furthermore, the woven or knitted fabric has a problem that it is difficult to dye white or light due to the color generated by zirconium silicide, and that the texture is strong and sticky.

  On the other hand, the composite fiber described in Patent Document 2 has a plurality of protrusions in the cross-sectional shape of the core part, and has a large surface area of the core part. . However, in such a composite fiber, it is necessary to increase the cross-sectional area of the nozzle hole during spinning in order to cope with a complicated cross-sectional shape of the core part. If it does so, the discharge distribution of the polymer which comprises a core part will not become uniform, but as a result, when a woven or knitted fabric is dye | stained, there exists a problem that a staining spot tends to generate | occur | produce.

  In terms of texture, the woven or knitted fabric is excellent in gloss and has little sliminess, but in reality the dry feeling that is preferred for sports clothing is scarce.

  The present invention eliminates the above-mentioned drawbacks of the prior art, exhibits an excellent heat retention effect, and at the same time, can be dyed in white and light colors, has few staining spots, and exhibits a good texture such as dry feeling. It is a technical problem to provide a yarn suitable for a woven or knitted fabric.

  As a result of intensive studies to solve the above problems, the present inventors have made the present invention.

  That is, in the present invention, first, the sheath part is composed of the polyester polymer A containing 0.01 to 0.3% by mass of the fluorescent brightening agent, and the core part is 5 to 25 mass of the metal oxide infrared absorber. % Polyester resin B, the mass ratio (A / B) of both polyester polymers is 90/10 to 40/60, and the fiber cross section has 3-5 protrusions on the outer periphery of the fiber and both A polyester polymer joined shape is composed of a composite fiber having a shape along the contour of the outer periphery of the fiber, and includes a group of thick fibers having a single yarn fineness of 3 dtex or more and a group of fine fibers having a single yarn fineness of 2 dtex or less. The composite fiber constituting the thick fiber group has a flat trunk portion and a protrusion, and the flatness (F) and the protrusion degree (T) satisfy a specific relationship, and each fiber Group of fibers Satisfy the ratio specified range of a few, it is an gist profiled cross fineness combined filament yarn elongation of the composite fibers constituting each fiber group satisfies a specific relationship.

  Since the core-sheath composite fiber yarn of the present invention is excellent in the infrared ray absorbing effect, it exhibits excellent heat retaining properties when made into a woven or knitted fabric. Further, the woven or knitted fabric obtained can be dyed in white or light color, has little dyeing spots, and has a good feeling such as dry feeling, and is therefore suitable for clothing use, particularly sports clothing.

It is a cross-sectional schematic diagram which shows one embodiment of the composite fiber which comprises a thick fine fiber group. It is a cross-sectional schematic diagram which shows one embodiment of the composite fiber which comprises a fineness fiber group. It is an example of the cross-sectional schematic diagram which shows the shape of the spinning hole of the spinneret which can be used for this invention.

  Hereinafter, the present invention will be described in detail.

  The blended yarn of the present invention is composed of a composite fiber having a specific composition and structure. Specifically, it is composed of two types of polyester polymers A and B and has a special core-sheath structure.

The polyester composition in A and B is not particularly limited as long as it is a polyester capable of forming a fiber, and for example, polyethylene terephthalate, polybutylene terephthalate, and the like can be employed. Further, if necessary, a predetermined component may be copolymerized therewith to obtain a copolyester. When the copolymerized polyester is employed, examples of the copolymer component to be used include isophthalic acid, 5-alkaliisophthalic acid, aromatic dicarboxylic acids such as 3,3′-diphenyldicarboxylic acid, adipic acid, sebacic acid, and succinic acid. And aliphatic dicarboxylic acids such as diethylene glycol, 1,4 butanediol, 1,4 cyclohexanediol and the like, alicyclic diols, P-hydroxybenzoic acid and the like.
Further, each polymer may contain an additive, a matting agent, an antistatic agent, an antioxidant and the like as long as the effects of the present invention are not impaired.

  In the composite fiber in the present invention, the sheath portion is composed of the polymer A. And in polymer A, it is necessary to contain 0.01-0.3 mass% of fluorescent whitening agents, Preferably 0.05-0.2 mass% is contained. When the content of the fluorescent brightening agent is less than 0.01% by mass, the color development of the fiber due to the metal oxide infrared absorber described later cannot be suppressed, and a sufficient whitening effect is given to the woven or knitted fabric. Can not be. On the other hand, if it exceeds 0.3% by mass, the fiber undergoes a concentration quenching phenomenon, resulting in an increase in yellowness of the fiber, and it is impossible to give a sufficient whitening effect to the woven or knitted fabric. In addition, it is preferable that the fluorescent whitening agent has the maximum fluorescence intensity in a wavelength region of 420 to 460 nm.

  Examples of the optical brightener used in the present invention include 2,5-bis (5′-t-butylbenzooxolyl (2)) thiophene (“Ubitex OB (trade name)” manufactured by Ciba Geigy), 4,4′-bis (2-benzoxazolyl) stilbene (“OB-1 (trade name)” manufactured by Eastman Chemical Co., Ltd.) and the like are mentioned, among which 4,4′-bis (2-benzoxazolyl) stilbene is preferable.

  On the other hand, the core of the composite fiber is made of polymer B. And in the polymer B, it is necessary to contain 5-25 mass% of metal oxide infrared absorbers, Preferably it is contained 7-17 mass%. When the content of the infrared absorber is less than 5% by mass, the fiber does not exhibit a sufficient infrared absorption effect, and a sufficient heat retaining effect cannot be given to the woven or knitted fabric. On the other hand, if it exceeds 25% by mass, the flexibility of the fiber disappears and the fiber becomes brittle, and the spinnability and processability of the yarn are significantly lowered.

Examples of the infrared absorber used in the present invention include antimony-doped tin oxide, tin-doped indium oxide, a mixture of titanium oxide and tin oxide, and the like. Also, the mass ratio of the polymers A and B in the composite fiber (A / B) needs to be 90/10 to 40/60, preferably 80/20 to 50/50. When the ratio of the polymer A exceeds 90% by mass, the ratio of the core portion in the fiber becomes low, and a sufficient infrared absorption effect cannot be obtained in the fiber. On the other hand, when the ratio of the polymer A is less than 40% by mass, a sufficient infrared absorption effect can be obtained, but the polymer B is easily exposed on the fiber surface, and the joining shape of both polymers can be made to conform to the outer periphery of the fiber. As a result, the flexibility of the fiber disappears and the fiber becomes brittle, and the spinnability and workability of the yarn are significantly reduced.

  Furthermore, the composite fiber in the present invention is also characterized in the structure.

  First, in the composite fiber, it is necessary to have a protrusion on the outer periphery of the fiber in the fiber cross section. The number of protrusions needs to be 3 to 5, preferably 3.

  When a predetermined number of protrusions are provided on the outer periphery of the fiber, the gap between the fiber bundles is filled with the protrusions when the fibers are converged, so that a yarn having a high fiber density can be obtained. As a result, since the amount of transmitted infrared rays is reduced when a woven or knitted fabric is obtained, the infrared absorption effect is improved as a whole. This effect is remarkable as compared with the case of the round cross-section fiber.

  On the other hand, when trying to provide more than 5 protrusions on the outer periphery of the fiber, it is necessary to increase the cross-sectional area of the nozzle hole, and as a result, the discharge distribution of the polymer B constituting the fiber core portion becomes non-uniform, Dyeing spots occur in the woven or knitted fabric. In addition, although depending on the shape of the protrusion, the fiber density in the yarn may be lower than in the case of the round cross-section fiber. On the other hand, when the number of protrusions is less than 3, the gaps between the fiber bundles cannot be filled, and the amount of transmitted infrared rays when the woven or knitted fabric is increased increases, so that the infrared absorption effect is also reduced. In the present invention, it is most preferable that the number of protrusions be 3, which makes the effect of preventing the nozzle hole cross-sectional area enlarged, makes the discharge distribution of the polymer B more uniform, and can greatly reduce the staining spots. .

  Moreover, in the composite fiber in this invention, the joining shape of the polymers A and B has comprised the shape along the outline of fiber outer periphery. By adopting such a shape, it is possible to prevent the polymer B from being exposed to the fiber surface. Conventionally, a core-sheath composite fiber having a round cross section in the core and an irregular cross section throughout the fiber has a problem in that the polymer constituting the core is easily exposed on the fiber surface, and the spinnability and workability of the yarn have been problematic. In the present invention, this problem can be solved by adopting such a structure.

  The blended yarn of the present invention is a blended yarn having a different shape and different fineness using the composite fiber as described above, and is composed of a plurality of fiber groups, and each fiber group needs to satisfy a specific requirement. is there.

  The mixed yarn of the present invention has a thick fiber group having a single yarn fineness of 3 dtex or more and a fine fiber group having a single yarn fineness of 2 dtex or less.

In the present invention, the texture of the woven or knitted fabric can be given a firm and dry feeling due to the presence of the thick fine fiber group, and the soft feeling and the swelling feeling can be simultaneously given by the presence of the fine fine fiber group.
When the single yarn fineness of the thick fineness yarn group is less than 3 dtex, the cross-sectional area of the fiber becomes small, so that it becomes impossible to repel the lateral force, bending and twisting applied to the fiber. In this case, the woven or knitted fabric cannot be given a firmness and stiffness, and further, the difference in fineness with the fibers constituting the fine-fineness fiber group is reduced. The single yarn fineness of the thick fineness yarn group is preferably 3.5 to 5 dtex.
Hand, when the fineness of the fine denier yarn group is equal to or greater than 2 dtex, the cross-sectional area of the fiber is increased, the texture of the woven or knitted fabric becomes rigid. However, when the single yarn fineness is less than 1.2 dtex, yarn breakage is likely to occur in the subsequent drawing and false twisting steps, and fluff and loops tend to occur in the mixed yarn. The single yarn fineness of the fine yarn group is particularly preferably 1.2 to 1.7 dtex.

Moreover, in the said thick fine fiber group, while the cross-sectional shape of a composite fiber has a flat trunk | trunk part and a projection part, flatness (F) and protrusion degree (T) are following formula (1), (2). Satisfied.
Flatness (F): L / W ≧ 4.0 (1)
Protrusion degree (T): 0.15 ≦ H / L ≦ 0.55 (2)
L: longest distance of the flat trunk in the fiber cross section (mm)
W: radius of the maximum inscribed circle in the fiber cross section (mm)
H: Vertical distance (mm) from the tip B of the protrusion with respect to the straight line connecting both ends A1 and A2 of the longest distance L of the fiber cross section
The flatness (F) is involved in improving the dry feeling and bulging feeling of the woven or knitted fabric. That is, by increasing the flatness (F), the movement and rolling of the fibers are suppressed due to the presence of the flat trunk portion against the lateral force, bending and twisting applied to the fibers. Even if swirling or impact is applied to the mixed yarn in the preparation step, the convex portions and the concave portions between the fibers are difficult to be bonded to each other, and as a result, the yarn porosity is maintained, and a woven or knitted fabric with a feeling of swelling is obtained.

  Thus, in order to suppress the filling action that the convex portions and the concave portions of the single yarns are bonded to each other and to keep the yarn porosity moderately, it is necessary to set the flatness (F) to 4.0 or more. is there. When it is less than 4.0, the trunk (W) becomes large or the trunk length (L) becomes short, and the cross-sectional shape of the fiber becomes a shape close to a circular deformation, resulting in movement and rolling of the fiber. When swirling or impact is applied to the mixed yarn in the weaving and knitting process and the preparation process, a filling action is generated, and a woven or knitted fabric with a feeling of swelling is formed.

  However, increasing the flatness (F) without limitation inevitably results in a smaller trunk width (W) or a longer trunk length (L). Under these circumstances, when the mixed yarn is twisted or false twisted, the cross-sectional shape of the fiber may be deformed, and a strong filling action may occur. If it does so, since there exists a tendency for a woven or knitted fabric to have a little stickiness and stiffness, the upper limit of flatness (F) is preferably 7. Moreover, as a minimum, 4.5 is preferable.

The degree of protrusion (T) of the fiber is related to the improvement in dry feeling that is achieved by the fingertip being caught when the finger is slid on the surface of the woven or knitted fabric, and the improvement in the porosity in the woven or knitted fabric.
The protrusion degree (T) is a ratio of the height (H) of the protrusion to the length (L) of the trunk, and is set to 0.15 to 0.55. If the degree of protrusion exceeds 0.55 with respect to the length of the trunk (L), the height of the protrusion (H) will inevitably become high, and against the lateral force, bending and twisting on the fiber Executives can not stand. If it does so, the void | porosity of a thread | yarn will become low by the filling effect | action by rolling of a fiber, and as a result, a woven / knitted fabric will generate | occur | produce and will produce the glossiness with a strong glare feeling.
On the other hand, when it is less than 0.15, the protrusion is lower than the trunk, so that the unevenness on the surface of the woven or knitted fabric is reduced, resulting in a woven or knitted fabric with a strong feeling of stickiness and slime.

  Here, the length (L) of the trunk, the height (H) of the protrusion, and the width (W) of the trunk will be described with reference to FIG.

  FIG. 1 is a schematic cross-sectional view showing one embodiment of a composite fiber constituting a thick fiber group.

  The maximum lengths A1 and A2 that connect the two protrusions that are substantially linear are determined, and the distance between the points A1 and A2 is the length (L) of the trunk.

  A perpendicular line is drawn from the tip B of the other protrusion with respect to the straight line connecting the ends A1 and A2 of the trunk, and an intersection point P is obtained, and the distance between B and P is defined as the height (H) of the protrusion.

  In the trunk portion system, an inscribed circle that contacts at least three points is drawn, and the radius of the largest inscribed circle S is defined as the width (W) of the trunk portion.

  In addition, since the composite fiber which comprises the thick fineness fiber group has comprised the cross-sectional shape which satisfies the said requirements, it necessarily has 3-5 protrusion on the fiber outer periphery.

  On the other hand, the composite fiber constituting the fine fiber group only needs to have 3 to 5 protrusions on the outer periphery of the fiber, and does not need to satisfy the above-described requirements for the thick fiber group.

  FIG. 2 is a schematic cross-sectional view showing one embodiment of the composite fiber constituting the fineness fiber group.

  Further, as the composite fibers constituting each fiber group, it is preferable to adopt those having different cross-sectional shapes instead of adopting the same cross-sectional shapes. Generally, each fiber group is preferably composed of fibers having 2 to 7 different cross-sectional shapes, thereby improving the quality of the woven or knitted fabric.

  3A to 3C show the shape of the spinneret of the spinneret, and each is suitable for obtaining a fiber having a cross-sectional shape as shown in FIGS. 2A to 2C. . FIG. 3D also shows the shape of the spinning hole, which is suitable for obtaining the fiber having the cross-sectional shape shown in FIG.

  Moreover, in this invention, it is preferable that the ratio of the number of fibers of a thick fiber group is 5 to 50% with respect to the whole mixed fiber, and it is more preferable that it is 5 to 20%. Thereby, the firmness, stiffness, and dryness of the woven or knitted fabric can be further emphasized.

  The ratio of the number of fibers in the fine fiber group is preferably 20 to 70%, more preferably 40 to 70%, based on the entire mixed yarn. Thereby, the soft feeling of a woven or knitted fabric and a feeling of swelling can be emphasized more.

Combined filament yarn of the present invention may be composed only of a large fineness fiber groups and small fineness fiber group described above, but if necessary, there is fineness fiber group in which the single yarn fineness exceeds 2dtex below 3dtex May be. In this case, the shape of the fiber cross section of the medium fineness fiber group only needs to have 3 to 5 protrusions on the outer periphery of the fiber in the fiber cross section, as in the case of the fine fiber group.
And in the mixed fiber of this invention, the elongation of the composite fiber which comprises each fiber group satisfies the following formula (3)-(5) simultaneously.
M ≦ 130 (%) (3)
N ≧ 80 (%) (4)
MN ≧ 20 (%) (5)
M: Average elongation (%) of the composite fiber constituting the thick fiber group
N: Average elongation (%) of the composite fibers constituting the fineness fiber group
The average elongation M needs to be 130% or less, and is more preferably 100 to 130% in consideration of the equation (5). When M exceeds 130%, when a mixed fiber is obtained, the draw ratio during stretching and false twisting tends to be high, and the fibers constituting the fineness fiber group tend to be partially cut, which is not preferable. . In this case, even if the draw ratio is set in accordance with the fineness fiber group, the residual elongation of the thickness fiber group is newly increased, and as a result, dyeing spots and the like are likely to occur when the woven or knitted fabric is dyed. Therefore, it can be said that it is not preferable anyway.

  Further, the average elongation N needs to be 80% or more, and is preferably 80 to 110% in consideration of the formula (5). When N is less than 80%, the fibers constituting the fine fiber group tend to be partially cut at the time of drawing and false twisting to obtain a mixed yarn, which is not preferable.

  Further, in the woven or knitted fabric, in order to realize a contradictory texture such as dry feeling and soft feeling, the difference between the two average elongations is set to 20% or more, preferably 25% or more. If the difference between the two average elongations is less than 20%, the physical properties of the mixed yarn that has undergone subsequent processes such as drawing and false twisting tend to be uniform, and it becomes difficult to give a soft feeling and a natural feeling to the woven or knitted fabric. Is not preferable.

  In addition, in order to appropriately express the above-mentioned opposite textures in the woven or knitted fabric, the elongation of the fibers having the smallest elongation in the thick fiber group and the fibers having the largest elongation in the fine fiber group. The degree difference is preferably 20% or less, and preferably 15% or less.

  In addition, when a medium-fine fiber group exists in the mixed yarn, from the viewpoint of the elongation range of the thick and fine fiber groups and the suppression of yarn breakage during stretching and false twisting, the fibers constituting the medium-fine fiber group The average elongation is preferably 100 to 120%.

By using the heterogeneous and different fineness mixed yarn of the present invention, a natural, rich and woven fabric with a soft texture can be obtained.
In order to produce the mixed yarn of the present invention, first, polyester polymers A and B are prepared. As a method for preparing the polymers A and B, in the polymerization step of the base polyester polymer, a method of adding a fluorescent brightener to A and an infrared absorber to B, respectively, And an infrared absorber added to B and melt kneaded. However, the addition of the fluorescent whitening agent and the infrared absorber in the polymerization stage may cause the aggregation of the fluorescent whitening agent and the infrared absorber and the deterioration of the spinnability. Therefore, the melt-kneading method is preferable in the subsequent step.
Then, the polymers A and B are spun into a mixed fiber. In this case, for example, a method of spinning from individual spinnerets to obtain each fiber group, combining yarns at the time of taking-up, and then blending the fibers, spinholes having different shapes as shown in FIG. For example, a method of melt spinning using a die having a plurality of fibers and then mixing the fibers later. However, in any case, the spinning speed is preferably 3000 m / min or more, and it is wound in the state of a semi-undrawn yarn, and then drawn, blended and formed into a blended yarn. False twisting may be performed as necessary.

  Here, the woven or knitted fabric using the mixed yarn of the present invention will be described.

  In such a woven or knitted fabric, it is preferable to satisfy an absorption rate of 35% or more in an infrared region having a wavelength of 700 to 2000 nm. Thereby, since the outstanding infrared absorption effect can be show | played, the desired heat retention effect can be anticipated.

  In the woven or knitted fabric, the fluorescent whiteness (WI) is preferably 90 or more. As a result, a woven or knitted fabric having excellent whiteness is obtained, and white and light colors can be used.

  EXAMPLES Next, although an Example demonstrates this invention concretely, this invention is not limited to these Examples. In addition, the measuring method and evaluation method in an Example are as follows.

1. Intrinsic viscosity Measured at a temperature of 20 ° C. using a mixture of equal amounts of phenol and ethane tetrachloride as a solvent.

2. Single yarn fineness After the mixed yarn is cut to a length of about 25 cm, it is split, and “DENIER COMPUTER DC-11 (trade name)” manufactured by Search Corp. is used to obtain the single yarn fineness for all fibers. It was measured. Then, the obtained results were classified into a thick fine fiber group, a fine fine fiber group, and a medium fine fiber group, and the average value of single yarn fineness of all the fibers in the group was calculated.

3. Average elongation of fiber group 2. The fibers were separated by the same means as described above, and the elongation of all the fibers was measured using an Instron type tensile tester under the conditions of a holding interval of 10 cm and a pulling speed of 10 cm / min. And the obtained result is 2. Similarly, it divided into each fineness group and calculated each average elongation.

4). Flatness (F), protrusion degree (T)
2. The fibers were separated and separated in the same manner as described above, and a cross-sectional photograph was taken using an electron microscope for all the fibers in the thick fiber group. And flatness and protrusion degree were calculated | required based on these photographs, and the average value was made into F and T.

5. The obtained mixed fiber was used as a tubular knitted fabric, and the infrared absorption rate was measured. Using a self-recording spectrophotometer “UV-3100 (trade name)” manufactured by Shimadzu Corporation, the absorbance and transmittance of the tubular knitted fabric at a wavelength of 700 to 2000 nm were measured. The wavelength of 1700 nm of the measurement result was read, and the absorptance and transmittance were evaluated by the evaluation method described below.
<Absorption rate evaluation method>
36% or more: ◎
26-35%: ○
16-25%: △
15% or less: ×
<Evaluation method of transmittance>
15% or less: ○
16-20%: △
21% or more: ×

6). Fluorescence whiteness (WI)
The obtained mixed yarn was made into a tubular knitted fabric, and the fluorescent whiteness (WI) was measured. Using a spectrophotometer “CM-3700D (trade name)” manufactured by Konica Minolta, UV was measured under the condition of 99.9% according to the ASTM-E-313 method. By the evaluation method described below, the fluorescent whiteness was evaluated, and ○ was accepted.
<Method for evaluating fluorescent whiteness (WI)>
90 or more: ○
71-89: △
70 or less: ×

7). After using the mixed yarn obtained from the dyed spots to form a tubular knitted fabric, a Bayer dye “Terasil Navy Blue SGL (trade name)” is used at 2.0 ° C. in a bath ratio of 1:50 at 99 ° C. The tube knitted fabric was dyed under the conditions of the lower 60 minutes. After dyeing, the occurrence of stained spots on the tubular knitted fabric was visually evaluated in the following three stages.
○: Staining spots are hardly observed Δ: Staining spots are slightly recognized ×: Staining spots are remarkably recognized

8). Feeling evaluation
For the firmness, firmness, swelling, softness, and dryness, see 7. The cylindrical knitted fabric used in the above and the evaluation reference yarn (triangular cross section yarn: fineness 110 dtex (single yarn fineness 2.5 dtex)) were similarly knitted in the same manner, and the sensory evaluation by tactile sensation 3 Rated by stage.
Better than evaluation standard knitted fabric: ○
Equivalent to knitted fabric of evaluation standard yarn: △
Inferior to the knitted fabric of the evaluation standard yarn: ×

9. The spinnability was evaluated based on the number of cut yarns per spindle when the spinnable mixed yarn was spun continuously for 24 hours.
0 to 1 time: ○
2 to 3 times: △
4 times or more: ×

10. Workability above 9. In the same manner as in the case of continuous spinning for 24 hours, the workability was evaluated by the number of times the machine base stopped due to fluff generation and yarn breakage per machine base.
0-2 times: ○
3-4 times: △
5 times or more: ×

Example 1
Polymer A is obtained by melting and kneading 0.1% by mass of 4,4′-bis (2-benzoxazolyl) stilbene as a fluorescent brightening agent into polyethylene terephthalate having an intrinsic viscosity of 0.68, chipping by a conventional method, and drying. It was. On the other hand, polymer B was obtained by melting and kneading 10% by mass of antimony-doped tin oxide as an infrared absorber in polyethylene terephthalate having an intrinsic viscosity of 0.73, forming chips by a conventional method, and drying. Then, polymers A and B are introduced into a core-sheath composite spinning apparatus having a spinneret having 44 orifices as shown in FIGS. 3 (a) to 3 (d), spinning speed is 3000 m / min, spinning temperature is 290 ° C., discharge amount. The melt spinning was performed under the condition of 33 g / min to obtain a 110 dtex 44f semi-undrawn yarn composed of a composite fiber having a mass ratio (A / B) of both polymers of 80/20.

  Subsequently, the semi-undrawn yarn was false twisted under conditions of a draw ratio of 1.37, a heat treatment temperature of 160 ° C., and a twist number of 3670 T / M, and further mixed to obtain a target mixed yarn.

  When the cross section of the composite fiber constituting the drawn yarn was observed using an electron microscope, it was confirmed that the joint shape of both polymers was a shape along the contour of the fiber outer periphery.

(Examples 2-9, Comparative Examples 1-4, 6-21)
The same procedure as in Example 1 was performed except that each condition was changed as shown in Table 1.

  In Examples 2 to 9 and Comparative Examples 1, 2, and 6 to 21, drawn yarns can be obtained. In the obtained drawn yarns, the joint shape of both polymers is the outer circumference of the fiber as in the composite fiber in Example 1. It was confirmed that the shape was in line with the outline.

(Comparative Example 5)
A drawn yarn was obtained in the same manner as in Example 1 except that titanium oxide was used instead of antimony-doped tin oxide. In the obtained drawn yarn, like the conjugate fiber in Example 1, it was confirmed that the joining shape of both polymers had a shape along the contour of the fiber outer periphery.

The mixed yarns obtained in Examples 1 to 9 are excellent in workability, and the obtained knitted fabric has excellent infrared absorption performance with good infrared absorption rate, low infrared transmission rate, and whiteness. In addition, it was excellent in dyeability, and had a texture that had a good feeling of firmness, stiffness, dryness, softness and swelling.

  On the other hand, since the mixed fiber of Comparative Example 1 has a low content of infrared absorbing inorganic particles, and the mixed fiber of Comparative Example 2 has a small polymer ratio in the core, sufficient infrared absorbing performance can be obtained. There wasn't. Furthermore, the blended yarn of Comparative Example 3 has a high content of infrared absorbing inorganic particles, and the blended yarn of Comparative Example 4 has a high polymer ratio containing the infrared absorbing inorganic particles in the core, so that the spinnability is high. Unfortunately, it was not possible to collect blended yarn.

  The mixed fiber of Comparative Example 5 could not obtain the infrared absorption effect because the fine particles added to the core polymer were not the infrared absorber. Since the blended yarn of Comparative Example 6 has a high content of the fluorescent brightening agent, the yellowness increases, and since the blended yarn of Comparative Example 7 does not contain the fluorescent brightening agent, sufficient whiteness is achieved. Could not get. In the mixed yarn of Comparative Example 8, the fine and medium fineness fiber group contained fibers having a cross-sectional shape with many protrusions, and thus stained spots were generated. In Comparative Example 9, since the single yarn fineness of the thick fineness fiber group was thin, the knitted fabric did not have a firmness or firmness.

  In Comparative Example 10, the flatness (F) in the fibers of the thick fine fiber group was low, so that the knitted fabric had a firm texture with no feeling of swelling. In Comparative Example 11, on the contrary, the flatness (F) was high, so that the obtained knitted fabric had a texture with no firmness and stiffness.

  In Comparative Example 12, since the degree of protrusion (T) was low, unevenness on the surface of the knitted fabric was reduced, and a texture with a feeling of stickiness and slime was obtained. In Comparative Example 13, the degree of protrusion (T) was high, so that the obtained knitted fabric was crushed and glossy gloss was generated.

  In Comparative Example 14, there is no fine fiber group, and in Comparative Example 18, the ratio of the thick fiber group is high. In Comparative Example 19, the ratio of the fine fiber group is low, so that both are obtained. The knitted fabric emphasized the firmness and firmness, resulting in a soft texture.

  In Comparative Example 15, there is no thick fine fiber group, and in Comparative Example 21, since the ratio of the fine fine fiber group is high, the obtained knitted fabric does not have a firmness or firmness, and only the soft feeling is emphasized. It became.

  Furthermore, in Comparative Example 16, since the elongation of the fine fiber group was low, the fibers of the fine fiber group were partially cut during false twisting, and as a result, fluff was generated. In Comparative Example 17, when the elongation of the thick fine fiber group was high and the draw ratio during false twisting was increased to match the thick fine fiber group, fluff was generated on the fine fine fiber group side. For this reason, the quality of the knitted fabric in both was poor.

In Comparative Example 20, since the difference in average elongation between the thick and fine fiber groups was small, the obtained knitted fabric was strong and lacked softness.

a: core protrusion b: sheath protrusion L: trunk length W: trunk width H: protrusion height

Claims (1)

The sheath part is composed of polyester polymer A containing 0.01 to 0.3% by weight of the optical brightener, and the core part is composed of polyester polymer B containing 5 to 25% by weight of the metal oxide infrared absorber, The mass ratio (A / B) of both polyester polymers is 90/10 to 40/60, and the cross section of the fiber has 3 to 5 protrusions on the outer periphery of the fiber, and the joining shape of both polyester polymers is the contour of the outer periphery of the fiber. The fine fiber group includes a thick fiber group having a single yarn fineness of 3 dtex or more and a fine fiber group having a single yarn fineness of 2 dtex or less, and constitutes a thick fiber group. The composite fiber has a flat trunk portion and a protrusion, and the flatness (F) and the protrusion degree (T) satisfy the following formulas (1) and (2), and the fibers of the thick fine fiber group Number ratio is mixed The ratio of the number of fibers in the fine fiber group is 5 to 50% with respect to the entire yarn, and the ratio of the number of fibers in the fine fiber group is also 20 to 70%. A blended yarn with irregular and different sizes, which is characterized by satisfaction.
Flatness (F): 7.0 ≧ L / W ≧ 4.0 (1)
Protrusion degree (T): 0.15 ≦ H / L ≦ 0.55 (2)
L: longest distance of the flat trunk in the fiber cross section (mm)
W: radius of the maximum inscribed circle in the fiber cross section (mm)
H: Vertical distance (mm) from the tip B of the protrusion with respect to the straight line connecting both ends A1 and A2 of the longest distance L of the fiber cross section
M ≦ 130 (%) (3)
N ≧ 80 (%) (4)
MN ≧ 20 (%) (5)
M: Average elongation (%) of the composite fiber constituting the thick fiber group
N: Average elongation (%) of the composite fibers constituting the fineness fiber group

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