JPH0796729B2 - Speckled yarn and manufacturing method thereof - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a false twisted textured yarn with unevenness in thickness, and more specifically to a polyester textured yarn with large heat shrinkage and small crimp elasticity. It is a thing.

(Prior Art) Conventionally, there are two types of filament yarns that are widely known as false-twisted polyester yarns. One is a so-called triple winding yarn, which is provided with an excessively supplied yarn in the false twisting and twisting process and wound around a core yarn. The other one is to perform false twisting or simultaneous drawing false twisting on a yarn that has been previously provided with thickness unevenness. The present invention belongs to the latter, and hereinafter, the fluff yarn refers to the latter.

The purpose or aim of the present invention will be shown in comparison with conventional fluff yarn. Conventional fluffy yarns are obtained by false-twisting (including simultaneous drawing) of partially drawn yarns or partially-drawn yarns and drawn yarns, and the false twist set temperature used at this time is 190 It is up to 220 ° C and the false twist number (T) is as high as T = (2400 to 2500) (150 / D) ^1/2 (t / m). This is because the conventional fluffy yarn is intended to be substantially thick as well as to be bulky like a normal bulky false twisted yarn. That is, the false twist set temperature is set higher than the crystallization temperature of the polyester to promote crystallization, reduce the shrinkage of the fiber, and strengthen the crimp set. In addition, a high number of false twists is used to achieve high crimping. Numerical example shows that the hot water shrinkage rate at 98 ℃ is about 0.5.
~ 3%, and the crimp elastic modulus is 30% or more. However, these physical properties are not always appropriate as the texture of the woven or knitted fabric. In other words, the crimps are very well repelled in the finishing process of the woven or knitted fabric, especially the hot water relaxation process, to give the woven and knitted fabric a deformation space, but the fibers are confined in the structure of the woven and knitted fabric and the fibers and the yarns and the yarns are pressed against each other violently To talk to each other. Also, the high crystallinity of the fibers makes it difficult for the fibers or yarns to adapt to the bending of the texture of the woven or knitted fabric. In other words, it is supposed to repel tissue bending. These make the texture of the woven and knitted fabric hard and lose the suppleness. Especially, it is not suitable as a yarn in the silk field where softness and flexibility are required.

Further, the conventional fluffy yarn is also subject to defects and great restrictions in terms of manufacturing. That is, an unstretched or semi-stretched portion with insufficient molecular orientation is exposed to the high temperature heater and passes through. At this time, the insufficiently oriented portion causes sticking, softening, or brittleness. The glue is generally a yarn that gives the woven and knitted fabric a feeling of roughness and has some roughness. For softening and brittleness, false twisting process (including drawing and false twisting)
It leads to the cutting of yarn. In particular, when the supplied yarn is composed only of partially stretched yarns and the proportion of unstretched portions (including semi-stretched) is large or the length is long, the source yarn is partially stretched yarns and unstretched yarns. If it is composed of, the tendency is large.

(Problems to be Solved by the Invention) Accordingly, the object of the present invention is to obtain a polyester false twisted yarn that can obtain a soft and supple texture as a texture of a woven or knitted fabric, and a wool as a material. Not only in the field, to obtain a processed yarn that can be applied to the silk field where conventional fluff is not possible, and as the morphology, it is possible to obtain it arbitrarily without restrictions such as the length and amount ratio of the flecks. With regard to (2), there is no sticking of the yarn and a yarn of any spot shape can be obtained without yarn breakage.

(Means for Solving Problems) First, the texture of the woven or knitted fabric made of the fluff yarn of the present invention will be described. The woven or knitted fabric using the fluff yarn of the present invention is soft and supple. The factor that most effectively brings about this feeling is to satisfy both the high shrinkage and the low crimp modulus. Regarding the shrinkage, the hot water shrinkage rate is particularly important, and in the present invention, the hot water shrinkage rate at 98 ° C. needs to be 6% or more for both the thin portion and the thick portion. The crimp modulus is 1 to 15
Set% to an appropriate range.

The hot water behavior of a woven or knitted fabric using the yarn of the present invention in the relax, dyeing process and the like is shown below. The yarn of the present invention originally has a small crimp elastic modulus and a large amount of hot water shrinkage, so that the extreme crimping is suppressed. Further, the yarn of the present invention has a large degree of relaxation of molecular orientation, as represented by the large shrinkage of hot water. These suppress the crimps of the yarns in the structure of the woven or knitted fabric and form a crimped form that fits the structure. In addition, the fact that the hot water shrinkage is large causes the yarns to be involved and to be adapted to the bending of the woven or knit structure. This is the reason why the woven or knitted fabric using the yarn of the present invention is soft and supple, and is a woven or knitted fabric with no distortion. However, when the heat shrinkage is extremely large, it is not preferable that the yarns fit in the structure of the woven or knitted fabric beyond the deformation space of the yarns and the yarns are tightened. Normally 98 ° C hot water shrinkage is 25%
It is important that: In addition, it is preferable that the yarns have a partial difference in the yarn length (there is a difference in length between the yarns constituting the yarn), or the difference in the yarn length difference in the length direction. That is, the difference in yarn length has the effect of enhancing the swelling feeling of the woven or knitted fabric, and unevenness in the yarn length difference such as partial presence or quantitative change is very effective as a visual change of the woven or knitted fabric.

Hereinafter, description will be given while adding a manufacturing method for embodying the yarn of the present invention. FIG. 1 is a schematic view showing a false twisting device used in the present invention. R ₁ is a supply roller, R ₂ is a delivery roller, H is a heater, and S is a false twist unit. Reference numerals 1 and 2 denote supply raw yarns, and in the present invention, one or a plurality of yarns are used. However, at least one is a partially drawn yarn. 3 is a filament. The supplied original yarn is guided to the supply roller R ₁ and passed through a heater H, a false twist unit S, and a delivery roller R ₂ to be false twisted or simultaneously drawn and false twisted to form a fluffy yarn. FIG. 2 is a schematic view showing a partial stretching device. R ₃ is a supply roller, R ₄ is a delivery roller, L is a roller separation, G is a guide, 4 is an undrawn yarn, and 5 is a partially drawn yarn. The partially stretched yarn is usually produced at a (R ₄ / R ₃ ) speed ratio of 1 or more and a natural draw ratio (ND) or less. The thick portion is composed of an unstretched or semi-stretched portion with insufficient molecular orientation, and is referred to as an unstretched portion hereinafter.
The thin portion is mainly composed of a semi-stretched portion in which stretching or molecular orientation has advanced, and is called a stretched portion.

The lengths and thicknesses of the unstretched portion and the stretched portion are important in relation to the subsequent false twisting (stretching simultaneous false twisting) step as well as in relation to the shape and morphology of the generated fluff yarn. First, the length will be described.
In the present invention, the requirement regarding the length of the fluff yarn is that at least the length of the thick portion satisfies 15 to 400 mm. This is a visual requirement for fluff yarn, and is an amount that can sufficiently fulfill the nature and function of fluff yarn. In other words, it should not be too short and lose its value as a fluff, or one that gets stuck in pieces and loses its naturalness. It should not be one that does not function as fluff beyond 1/2). The generation of the thick portion in the present invention may be obtained from the unstretched portion or the stretched portion, as will be described later in detail. These lengths and the length of the thick part of the fluff do not always match (generally tend to be shorter), but it is important to satisfy at least the length of 15 to 400 mm.

Various lengths of the unstretched portion and the stretched portion can be obtained depending on the natural stretching ratio of the unstretched yarn used, the stretching distance (distance between rollers), and the speed ratio. To meet the above length, for the unstretched part Regarding the extension part It is preferable to stretch so that

Regarding the thickness of the unstretched portion and the stretched portion, the greater the difference ratio, the easier it becomes to catch the eye. However, the difference ratio is not so good that it is so large that an extremely large difference ratio is unnatural, and depending on the type of woven or knitted material, a very gentle one may be required. Usually, when the average fineness is D ₀ , it is in the range of (0.4 to 2.5) × D ₀ . In the present invention, when the difference ratio is extremely large, for example, a partially drawn yarn formed by using a low speed spinning winding undrawn yarn significantly impairs the false twisting (including the simultaneous drawing false twisting) processability. Generally, those using a spinning winding speed of 300 m / mm or more are excellent in false twisting workability (0.4 to 2.5) and also satisfy D ₀ .

With respect to this apparatus, it does not matter if the supply roller is heated or a heater is provided between the rollers. However, the most important thing in the present invention is these temperatures (hereinafter referred to as stretching temperature).
Is not too high. This is because the higher the temperature, the smaller the heat shrinkage of the obtained yarn. In order to satisfy the requirement of 98 ° C. hot water shrinkage of 6% or more, which is a requirement of the present invention, at least the partially drawn yarn must also be satisfied. The drawing temperature that satisfies this depends on the polymer constituting the yarn, but is usually 160 ° C. or lower. More specifically, it is 160 ° C or lower for copolyester and 140 ° C or lower for polyethylene terephthalate.

FIG. 3 is a schematic diagram showing a yarn in which two kinds of polyesters having different natural draw ratios are spun from the same spinneret and partially stretched. A is a fiber made of a polymer having a small natural draw ratio,
B indicates a fiber composed of a large amount of polymer. 6 represents an unstretched fiber portion, and 7 represents a stretched fiber portion or a stretched fiber. A portion containing unstretched (including semi-stretched) fibers is called an unstretched portion, and a portion not containing it is called a stretched portion. Fig. 3- (I) is A
It is drawn at a natural draw ratio of the fiber or more and a natural draw ratio of the B fiber or less. In reality, the A fiber may contain some unstretched fiber, but the B fiber mainly constitutes the unstretched portion. Hereinafter referred to as F type. FIG. 3- (II) is drawn at a natural draw ratio of A fiber or less. Both A fiber and B fiber have undrawn fibers, and the amount and length of B fiber are large. This case is called P-type. It is important to satisfy the above conditions even when using the same base. In the case of F type, the stretching distance (distance between rollers) is increased. If the difference in natural stretching ratio is large, a long unstretched portion can be easily obtained. In addition, in applying the above formulas (1) and (2), the fiber (ND) having a large natural draw ratio may be used.

Further, as a method of obtaining a partially stretched yarn other than the above, there is a method of changing the speed of the supply roller or the delivery roller, or providing a guide between the rollers to change the yarn path to temporarily bring the yarn into a stretched state below the natural draw ratio. Even in these cases, the present invention is not an exception, and the obtained yarn has a length of unstretched portion or stretched portion of 15 to 400 mm (0.4 to 2.5) × D _{0 for} fineness unevenness and 160 ° C. for stretching temperature as described above. Anything satisfying the following may be used.

In the present invention, one or a plurality of yarns are used as a raw yarn for supply, and various kinds of fluffy yarns can be obtained. Although its usage is complex and diverse, the main representative examples are as shown in Table 1. However, the object of the present invention is to have a high heat shrinkability, and in order to satisfy the requirements of the present invention, it is necessary that the yarns of any of the supplied raw yarns have a hot water shrinkage ratio of at least 98% at 98 ° C. It's important.

In the false twisting method, false twisting can be carried out when the supplied raw yarn contains drawn yarn or drawn fiber, and false twisting or simultaneous drawing false twisting process can be carried out when it does not contain the drawn yarn or drawn fiber. Further, the draw ratio at this time can be a midway draw ratio because the false twist set temperature used in the present invention is low.

The thick portion of the fluff is often generated mainly from the undrawn portion. The length is complicated depending on the combination of the raw yarns to be supplied and whether or not the false twisting is involved. Generally, it tends to be shorter when stretching is involved. However, with the combination of the raw yarns, the partially drawn yarn 2
In the case of using a book, it becomes long when the unstretched portions are continuous when viewed from the extreme. The thick portion of the fluffy yarn may occur from the stretched portion. This is the case of simultaneous drawing false twist formed by using undrawn yarns and partially drawn yarns belonging to type IV in Table 1. That is, the unstretched overlapped portion is thinned by stretching during false twisting, and the stretched portion and the unstretched overlapped portion form a thick portion without being stretched.
In any case, it is important that the length (average) of the thick portion that has the naturalness and function as the fluff is 15 to 400 mm. In particular, consideration should be given to the case where the raw yarn to be supplied is false twisting accompanied by drawing using only one partially drawn yarn. Originally, the amount of the unstretched portion between the supply roller and the delivery roller changes every moment, and it is not possible to stretch the entire unstretched portion at a constant stretching ratio. But too short (15mm
In the following cases, it is advisable to carry out false twisting using the intermediate draw ratio.

Further, the yarn length difference (difference in length between yarn constituent fibers) occurs during false twisting (including simultaneous false twisting during drawing) if there is a difference in the degree of molecular orientation (elongation) in the supplied raw yarn. Further, the size thereof is larger as the difference in the degree of molecular orientation is larger. In the case of Type I in Table 1, a difference in yarn length is relatively unlikely to occur, but a slight difference in the degree of orientation between the fibers forming the unstretched portion at the time of partial stretching, or the presence of stretched fibers or unstretched fibers It is generated by assembling. In the other type, there is a part where undrawn and drawn are combined in the supplied raw yarn, and a part having a large yarn length difference occurs (a large yarn length difference unevenness occurs). In particular, when a plurality of partially drawn yarns are used as the raw yarns to be supplied, the yarn length difference becomes complicated and diversified in the length direction of the yarn. The type V in Table 1 is a fluffy yarn in which there is a difference in yarn length over the entire yarn and the amount of the yarn is partially large or small. The difference in yarn length also gives the yarn a deformation space in terms of feeling and brings about a swelling feeling. Further, it is more preferable as a fluff yarn by visually changing the shape of the yarn.

Next, the conditions for false twisting (including false twisting simultaneously with drawing) will be described. The false twist set temperature (heater temperature) used in the present invention is usually 160 ° C. or lower to room temperature. This is intended to not compromise heat shrinkage. The heat shrinkage of the yarn becomes smaller as the false twist set temperature becomes higher, and becomes extremely small especially above the crystallization temperature. In order to achieve the hot water shrinkage rate of 6% or more at 98 ° C required by the present invention, 160 ° C or less is preferable. More specifically, depending on the crystallinity of the yarn, the copolyester having poor crystallinity can be applied up to a relatively high temperature. For polyethylene terephthalate, temperatures below about 140 ° C are preferred.

The false twist number generally relates to the degree of crimp, and the higher the false twist number, the higher the crimp and the higher the crimp elasticity. However, the crimp elasticity is not uniquely related to the false twist number, but is greatly related to the false twist set temperature, heat shrinkage, crystallinity and the like. That is, even if the yarn has a large false twist number and is bulky, a yarn having a large heat shrinkage and not having advanced crystallinity exhibits only a small crimp elasticity. This is the purpose of the present invention, and is the reason why a low false twist set temperature is used to prevent a decrease in heat shrinkage of the yarn and to achieve low crystallization. In the field of clothing, there are fields in which crimping and twisting of fibers are required to be extremely small, and fields in which silk is used. It is convenient that they have a low false twist set temperature and a small false twist number. Generally, the number of false twists depends on the false twist set temperature and the heat shrinkage of the supplied raw yarn, and the crimp elastic modulus is 0.5 to 15% and the hot water shrinkage at 98 ° C is 6%.
The false twist number (T) is T = (1200 to 2700) (150 / D) ^1/2 (t / m) in order to achieve the above value. However, D is the average fineness of the fluffy yarn after false twisting (including simultaneous drawing false twisting) processing.

It should be noted that it is permissible to subject the supply raw yarn to the fluid disturbing treatment or the generated irregular yarn to the same treatment prior to the false twisting (including simultaneous drawing false twisting) processing. In particular, when the same drawn part partially drawn yarn having a plurality of supply yarns is used, the handleability of the yarn is made effective.

The crimp elastic modulus and the hot water shrinkage at 98 ° C. are measured as follows. In particular, the present invention requires a hot water shrinkage rate of 6% or more in each part of the fluff yarn and the partial drawing, and is shown together with the method for measuring a uniform yarn.

1) Crimped elastic modulus (K) 0.001g is made by making a 1 meter circumference tape wound 90 times.
Immerse in hot water at 90 ° C for 30 minutes under a load of / d. Remove the load and air dry at room temperature. Then, measure the length l ₁ of the cassette under a load of 0.001 g / d. Continuously, the length of the cassette l ₂ under a load of 0.1 g / d
To measure. The crimp elastic modulus (K) is given by the following equation.

2) 98 ° C hot water shrinkage rate (S) (a) Uniform yarn (drawn yarn, undrawn yarn, etc.) Make a 90-degree wound yarn with a circumference of 1 meter. 0.1 g / d
Measure the length l ₀ of the hank under load. Next, it is immersed in hot water at 98 ° C for 30 minutes under a load of 0.0005 g / d. Remove the load and air dry at room temperature. Then measure the length l ₃ of the skein under a load of 0.1 g / d. The hot water shrinkage rate at 98 ° C is given by the following equation.

(B) Non-uniform yarn (partially drawn yarn irregular yarn) Mark thick and thin parts on the yarn. Measure the lengths l ₀₁ and l ₀₂ under a load of 0.1 g / d. Next 0.0005
Immerse in hot water at 98 ° C for 30 minutes under a load of g / d. Remove the load and air dry at room temperature. Then, under 0.1g / d load, measure the lengths l ₃₁ and l ₃₂ of the thick and thin parts. 50 this
Repeat times. At this time, the hot water shrinkage rate at 98 ° C is given by the following equation.

However, the load is calculated by the following formula.

(Examples) Next, the details of the present invention will be described with reference to Examples and Comparative Examples. Table 2 is a summary of examples and comparative examples. The partial drawing and false twisting devices used were those shown in FIGS. 2 and 1, respectively.

Example 1 was a case where one partially drawn yarn was used, and a woven fabric that was soft and supple in thickness variation was obtained. However, the difference in yarn length between yarns was only slightly visible in the thick part. Comparative Example 1 is Example 1
The same partially stretched yarn was used, but the yarn was broken during false twisting. This was because the unstretched part was exposed to high temperatures.

Example 2 is a case where two partially drawn yarns are used. A yarn length difference was generated at a portion where there was a difference in the degree of molecular orientation between the two yarns, and the yarn length difference varied in the range of 0 to 12% in the length direction of the yarn length. It was a quaint textile with changes in spots and soft and supple swelling.

Example 3 is a case where a partially drawn yarn and a drawn yarn are combined, which is similar to Example 2 but the variation in spots is slightly inferior. In Comparative Example 2, the same raw yarn as in the example was used, and the false twist set temperature was high, and the unstretched portion was stuck.

Example 4 uses a partially stretched yarn (F type) obtained by spinning the same spinneret of two types of polyethylene terephthalate having different intrinsic viscosities. The feature in this case is that a single original yarn is supplied and a yarn having a fineness and a difference in yarn length is obtained. The false twist number used was also small, and a yarn having a low crimp elastic modulus was obtained. The woven fabric had less disorder of fibers due to crimping, and natural spots were obtained in a silky texture. It should be noted that caustic weight reduction may be added to the fabric finishing step of this example.

[Brief description of drawings]

FIG. 1 is a schematic view showing a false twisting device, where R ₁ is a supply roller, R ₂ is a delivery roller, H is a heater, S is a false twist unit, 1 and 2 are supply original yarns, and 3 is a fluffy yarn. FIG. 2 is a schematic view showing a partially drawing device, R ₃ is a supply roller, R ₄ is a delivery roller, L is a distance between rollers, G is a guide, 4 is an undrawn yarn, and 5 is a partially drawn yarn. FIG. 3 is a schematic view showing a partially drawn yarn using a yarn obtained by spinning the same spinneret of two kinds of polyesters having different natural draw ratios, where A is a fiber having a small natural draw ratio and B is a large fiber. 6 represents an unstretched fiber portion, and 7 represents a stretched fiber portion or a stretched fiber. It should be noted that Fig. 1- (I) was drawn at a natural stretching ratio of A fiber or more and B fiber or less, and Fig. 7 (II) was drawn at a natural stretching ratio of A or B or less. It is a schematic diagram which shows a partially drawn yarn.

Claims (4)

[Claims] 1. A false-twisted polyester yarn having a substantial thickness unevenness in the length direction, having an average length of at least 15 to 40.
It has a thick portion of 0 mm, and when the yarn average fineness is D, the yarn fineness unevenness is in the range of (0.4 to 2.5) × D, and the thin portion with 98 ° C hot water average shrinkage is 6% or more in both thick portions. And
And the crimped elastic modulus of the yarn is in the range of 1 to 15%. 2. The fluffy yarn according to claim 1, which has yarn length difference and yarn length difference unevenness in the length direction. 3. The hot water shrinkage rate at 98 ° C. is 6% or more, and the average length of either the unstretched portion or the stretched portion is 15 to 400 mm.
At least one partially drawn yarn in the range is used, and the partially twisted yarn has a false twist set temperature of room temperature to 160 ° C and a false twist number (T) of T = (1200 to 2700) (150 / D) ^1/2 ( T / m) false twisting or simultaneous drawing false twisting. 4. A polyester which is spun as a partially stretched yarn at a speed of 300 m / min or more and then stretched so that the average length of either the unstretched portion or the stretched portion is in the range of 15 to 400 mm. The method for producing fluff yarn according to claim 3, wherein fibers are used.