JP2022552434A - Side-by-side self-crimping elastic fiber and method for producing the same - Google Patents

Abstract

The present invention relates to a side-by-side self-crimping elastic fiber and a method for making the same, wherein after dispensing melts of compatible or partially compatible first and second fiber-forming polymers (P1 and P2), the same manufactured by extrusion through discharge holes m and n in a spinneret, the melt of P1 and P2 flowing through distribution holes A, B to discharge hole m and through distribution holes C, D to discharge hole n; A, B or C, D are cylindrical holes of the same height, the diameter ratio of A to B is 1.10-1.20:1, and the diameter ratio of C to D is is 1:1.10-1.20, the difference in apparent viscosity between the P1 melt and the P2 melt is no more than 5% at the inlets of A to D, and the fibers produced are A P2/P1 side-by-side composite single yarn having a mass ratio of 3:2 to 2:1 with the consists of The present invention solves the problem of "banding" in side-by-side composite fiber knit fabrics. [Selection drawing] Fig. 1

Description

The present invention belongs to the technical field of polyester fibers, and relates to a side-by-side self-crimping elastic fiber and a method for producing the same.

Crimp is an important index of fibers, affecting the spinning process and final product characteristics and application performance.

Among bicomponent conjugate fibers, side-by-side type bicomponent conjugate fiber is an important type, which utilizes the difference in heat shrinkability of the two components to bend the fiber away from the fiber axis direction, resulting in a permanent It exhibits a three-dimensional helical crimp and obtains a crimp like a wool fiber. Such fiber crimping does not require the deforming process that ordinary thermoplastic fibers undergo to obtain crimps, and avoids thermal damage to chemical fibers. It is also called a three-dimensional crimped fiber, and such crimps are stable and have high elasticity. can be given to Side-by-side bicomponent conjugate fibers with different performances can be obtained by changing the high polymer properties of the components, the cross-sectional shape, the distribution of the components, the proportion of the components, the spinning draft, and the parameters of the heat-setting process. Bicomponent conjugate fibers have the advantages of designable performance and high application value, so they are preferred and valued in the textile manufacturing industry.

Side-by-side bicomponent fibers have been widely applied in machine-woven fabrics, but in order to promote the fibers to be more widely applied in the field of knitting and weaving, the rule when side-by-side bicomponent fibers heat shrink Due to the formation of a helical crimped structure, there is a very difficult problem of random "striping" on the surface of the woven fabric, which is more pronounced in plain weave fabrics. This problem makes the side-by-side bicomponent fiber inapplicable to many kinds of knitted and woven products, such as imitation silk knitted and woven underwear fabrics. It is rated as a low-grade product of unevenness, which severely limits the development and application of side-by-side bicomponent knitted fabrics.

Therefore, it is of great significance to develop a knitted side-by-side bicomponent fiber fabric and a method for producing the same that does not produce random "stripes".

The present invention provides a side-by-side self-crimped elastic fiber and its manufacturing method to solve the problem of random "banding" when applying side-by-side bicomponent fibers in the prior art to knitted fabric products. for the purpose. The present invention provides X (second fiber-forming polymer/first side-by-side composite single yarn of fiber-forming polymer) and Y (second fiber in which the mass ratio of the first fiber-forming polymer and the second fiber-forming polymer is 2:3 to 1:2 By using a method in which the forming polymer/side-by-side composite single yarn of the first fiber-forming polymer) coexist in one fiber bundle, the first fiber-forming polymer and the second fiber-forming polymer are combined. Due to the different shrinkage modes and morphologies of the side-by-side composite fibers of the second fiber-forming polymer/first fiber-forming polymer having different mass ratios of It overcomes the formation of an orderly left and right spiral form of the bundles, and solves the problem of "stripe unevenness" that exists in knitted fabrics produced by a single pure X (or Y) fiber bundle. .

In order to achieve the above object, the technical means used by the present invention are as follows.

In a method for producing side-by-side self-crimping elastic fibers, depending on the particular spinning process, after dispensing the first fiber-forming polymer melt and the second fiber-forming polymer melt, in the same spinneret Extruding from the discharge hole m and the discharge hole n to produce a side-by-side self-crimping elastic fiber,
The distribution means distributing the first fiber-forming polymer melt through the distribution hole A and the second fiber-forming polymer melt through the distribution hole B to the discharge hole m, means to distribute the fiber-forming polymer melt of through the distribution hole C and the second fiber-forming polymer melt through the distribution hole D to the discharge hole n,
The first fiber-forming polymer and the second fiber-forming polymer are compatible or partially compatible (mixing the first fiber-forming polymer and the second fiber-forming polymer then judge the compatibility between the two polymers based on the change in the glass transition temperature of both),
At the inlets of distribution hole A, distribution hole B, distribution hole C, and distribution hole D, the difference in apparent viscosity between the second fiber-forming polymer melt and the first fiber-forming polymer melt is 5. % or less (the apparent viscosity is determined by simulation, specifically obtained by measuring the apparent viscosity of the polymer melt at a specific temperature using a rheometer),
Distribution hole A and distribution hole B are cylindrical holes with the same height, and the diameter ratio of distribution hole A and distribution hole B is 1.10 to 1.20:1. the distribution hole D is a cylindrical hole with the same height, the ratio of the diameters of the distribution hole C and the distribution hole D is 1:1.10-1.20;
Particular spinning processes are the POY, FDY, POY-DTY or POY-DT processes, further subjecting the fibers to a relaxation heat treatment after the POY, FDY and POY-DT processes are finished.

Specifically, the present invention dispenses a first fiber-forming polymer melt through distribution holes A and C and a second fiber-forming polymer melt through distribution holes B and D. and at the inlets of distribution hole A, distribution hole B, distribution hole C, and distribution hole D, the difference in apparent viscosity between the second fiber-forming polymer melt and the first fiber-forming polymer melt is 5% or less, each distribution hole is a cylindrical hole of the same height, and the ratio of the diameters of distribution holes A and B is not equal to the ratio of the diameters of distribution holes C and D By using the method, the mass ratio of the first fiber-forming polymer melt distributed to the discharge hole m and the second fiber-forming polymer melt distributed to the discharge hole n is equal to that of the first fiber-forming polymer melt distributed to the discharge hole n. Unlike the mass ratio of the fiber-forming polymer melt and the second fiber-forming polymer melt, X and Y can coexist in one fiber bundle, ensuring a difference in crimp form, Accordingly, by rationally setting the number and positional relationship of the distribution holes and the guide holes, the distribution is ensured to be performed smoothly. and control the discharge holes in the same circle to be all m or all n, to ensure that some Y can be mixed in the middle of some other X, orderly left, right The present invention does not need to adjust the shape of the discharge hole, just use a general side-by-side composite discharge hole, and the present invention uses a specific spinning process. The use allows the intrinsic viscosity of the first fiber-forming polymer melt and the intrinsic viscosity of the second fiber-forming polymer melt to cooperate with each other to allow the first polymer melt extruded from the discharge hole to It ensures that the apparent viscosities of the fiber-forming polymer component and the second fiber-forming polymer component are close to each other, and not only functions to control the mass ratio of the side-by-side composite single yarn, but also allows smooth spinning. It ensures that the produced fibers have excellent elasticity and high overall performance.

The principle of the invention is as follows.

に基づいて算出し、ここで、ΔＱは、溶融物の流量であり、ｄは、円管の直径であり、μは、円管の入口における溶融物の見かけ粘度であり、ｌは、円管の長さであり、ΔＰは、溶融物が円管を通過した後の圧力降下であり、式から分かるように、ΔＰ、μ、ｌが等しく維持する場合、２つの円管内を流動する流量の比は、円管の直径の４乗の比に近く、
本発明は、特定の紡糸プロセスに応じて、第１の繊維形成性重合体溶融物と第２の繊維形成性重合体溶融物を分配した後、同じ紡糸口金における吐出孔ｍと吐出孔ｎから押出し、サイドバイサイド型自己捲縮弾性繊維を製造し、分配とは、第１の繊維形成性重合体溶融物を分配孔Ａを介して、かつ第２の繊維形成性重合体溶融物を分配孔Ｂを介して吐出孔ｍに分配し、第１の繊維形成性重合体溶融物を分配孔Ｃを介して、かつ第２の繊維形成性重合体溶融物を分配孔Ｄを介して吐出孔ｎに分配することを指し、
分配孔Ａ（又はＣ）を流れる第１の繊維形成性重合体溶融物の流量と分配孔Ｂ（又はＤ）を流れる第２の繊維形成性重合体溶融物の流量との比は、

であり、ここで、ΔＱ１、ｄ１、μ１、ｌ１、ΔＰ１は、分配孔Ａ（又はＣ）に対応し、ΔＱ２、ｄ２、μ２、ｌ２、ΔＰ２は、分配孔Ｂ（或Ｄ）に対応し、分配孔Ａと分配孔Ｂの入口における第２の繊維形成性重合体溶融物と第１の繊維形成性重合体溶融物との見かけ粘度は、ほぼ同じであり（差が５％未満である）、分配孔Ｃと分配孔Ｄの入口における第２の繊維形成性重合体溶融物と第１の繊維形成性重合体溶融物との見かけ粘度は、ほぼ同じである（差が５％未満である）ため、μ１とμ２とは、ほぼ等しく、分配孔Ａ、分配孔Ｂ、分配孔Ｃ、及び分配孔Ｄの入口において、第２の繊維形成性重合体溶融物と第１の繊維形成性重合体溶融物との見かけ粘度の差は、５％以下であり、かつ分配孔Ａ、分配孔Ｂ、分配孔Ｃ、及び分配孔Ｄは、いずれも分配板に設けられ、自体のサイズが小さいため、第１の繊維形成性重合体溶融物が分配孔Ａを通過した後の圧力下降と第２の繊維形成性重合体溶融物が分配孔Ｂを通過した後の圧力下降とは、実質的に同じであり、第１の繊維形成性重合体溶融物が分配孔Ｃを通過した後の圧力下降と第２の繊維形成性重合体溶融物が分配孔Ｄを通過した後の圧力下降とは、実質的に同じであり、したがって、ΔＰ１とΔＰ２とは、ほぼ等しく、分配孔Ａと分配孔Ｂは同じ高さを有し、分配孔Ｃと分配孔Ｄは同じ高さを有するため、ｌ１とｌ２は等しく、
計算から分かるように、ΔＱ１／ΔＱ２とΔｄ１^４／Δｄ２^４は、ほぼ等しく、分配孔Ａと分配孔Ｂとの直径の比は、１．１０～１．２０：１であるため、分配孔Ａを流れる第１の繊維形成性重合体溶融物の流量と分配孔Ｂを流れる第２の繊維形成性重合体溶融物の流量との比は、約３：２～２：１であり、最終的に、吐出孔ｍから押出された単糸における第１の繊維形成性重合体と第２の繊維形成性重合体との質量比は、３：２～２：１であり、同様に、分配孔Ｃと分配孔Ｄとの直径の比は、１：１．１０～１．２０であるため、分配孔Ｃを流れる第１の繊維形成性重合体溶融物と分配孔Ｄを流れる第２の繊維形成性重合体溶融物との流量の比は、約２：３～１：２であり、最終的に、吐出孔ｎから押出された単糸における第１の繊維形成性重合体と第２の繊維形成性重合体との質量比は、２：３～１：２であり、
また、本発明が用いる第１の繊維形成性重合体と第２の繊維形成性重合体とは熱収縮率が異なり、さらに、第１の繊維形成性重合体と第２の繊維形成性重合体とを混合した後、この２種類の熱収縮率が異なる重合体は、相溶性又は部分的相溶性を有するため、相溶性の存在により、重合体は、同じ吐出孔（即ち、２種類の繊維形成性重合体溶融物が両方ともサイドバイサイド複合紡糸の方式で分配された後に押出される）を通過するときに一体に接着することができ、このような接着作用及び異なる熱収縮率の作用によって、同じ吐出孔から押出された２種類の重合体繊維（即ち、第２の繊維形成性重合体／第１の繊維形成性重合体のサイドバイサイド複合単糸）が熱処理された後に自己捲縮形態を形成することができ、それにより弾性を有し、このような自己捲縮形態は、具体的には、熱収縮率が大きい繊維形成性重合体が螺旋状捲縮の内側にあり、熱収縮率が小さい繊維形成性重合体が螺旋状捲縮の外側にあり、
同じ繊維束において、第２の繊維形成性重合体／第１の繊維形成性重合体のサイドバイサイド複合単糸の一部における第１の繊維形成性重合体と第２の繊維形成性重合体との質量比は、３：２～２：１であり、第２の繊維形成性重合体／第１の繊維形成性重合体のサイドバイサイド複合単糸の他の部分における第１の繊維形成性重合体と第２の繊維形成性重合体との質量比は、２：３～１：２であるため、異なる単糸の捲縮形態に一定の差異が存在し、このような差異は、純粋な第２の繊維形成性重合体／第１の繊維形成性重合体のサイドバイサイド複合単糸の整然とした左、右の螺旋形態の形成を打破する作用を果たし、製造されたサイドバイサイド型自己捲縮弾性繊維が弛緩熱処理された後に単糸の捲縮方向がランダムに分布するため、当該自己捲縮弾性繊維で製織された編地の表面にランダムな「縞状のむら」が生じない。 In the spinning process, the spinning melt is continuously flowing, in order to better control the melt flow rate, the melt flow rate formula in the melt circular tube is

where ΔQ is the melt flow rate, d is the diameter of the circular tube, μ is the apparent viscosity of the melt at the inlet of the circular tube, and l is the circular tube is the length and ΔP is the pressure drop after the melt has passed through the tube, and as can be seen from the equation, if ΔP, μ, l are kept equal, the flow rate of The ratio is close to the ratio of the 4th power of the diameter of the circular tube,
According to the particular spinning process, the present invention distributes a first fiber-forming polymer melt and a second fiber-forming polymer melt, and then from outlet holes m and n in the same spinneret. Extrusion to produce side-by-side self-crimping elastic fibers, dispensing includes first fiber-forming polymer melt through distribution hole A and second fiber-forming polymer melt through distribution hole B to discharge holes m, a first fiber-forming polymer melt through distribution holes C, and a second fiber-forming polymer melt through distribution holes D to discharge holes n. means to distribute
The ratio of the flow rate of the first fiber-forming polymer melt through distribution hole A (or C) to the flow rate of the second fiber-forming polymer melt through distribution hole B (or D) is

where ΔQ1, d1, μ1, l1, ΔP1 correspond to distribution hole A (or C), ΔQ2, d2, μ2, l2, ΔP2 correspond to distribution hole B (or D), The apparent viscosities of the second fiber-forming polymer melt and the first fiber-forming polymer melt at the inlets of distribution holes A and B are approximately the same (less than 5% difference). , the apparent viscosities of the second fiber-forming polymer melt and the first fiber-forming polymer melt at the inlets of distribution holes C and D are approximately the same (less than 5% difference ), .mu.1 and .mu.2 are approximately equal, and at the entrances of distribution hole A, distribution hole B, distribution hole C, and distribution hole D, the second fiber-forming polymer melt and the first fiber-forming polymer melt The difference in apparent viscosity from the coalesced melt is 5% or less, and distribution hole A, distribution hole B, distribution hole C, and distribution hole D are all provided in the distribution plate and are small in size. , the pressure drop after the first fiber-forming polymer melt passes through distribution hole A and the pressure drop after the second fiber-forming polymer melt passes through distribution hole B are substantially Equivalently, the pressure drop after the first fiber-forming polymer melt passes through distribution hole C and the pressure drop after the second fiber-forming polymer melt passes through distribution hole D are: are substantially the same, and therefore ΔP1 and ΔP2 are approximately equal, distribution holes A and B have the same height, and distribution holes C and D have the same height, so l1 and l2 are equal,
As can be seen from the calculation, ΔQ1/ΔQ2 and Δd1 ⁴ /Δd2 ⁴ are approximately equal, and the ratio of the diameters of distribution hole A to distribution hole B is 1.10 to 1.20:1, so distribution hole A The ratio of the flow rate of the first fiber-forming polymer melt through the distribution holes B to the flow rate of the second fiber-forming polymer melt through the distribution holes B is about 3:2 to 2:1, and finally Furthermore, the mass ratio of the first fiber-forming polymer to the second fiber-forming polymer in the single yarn extruded from the discharge hole m is 3:2 to 2:1. Since the diameter ratio between C and distribution holes D is 1:1.10-1.20, the first fiber-forming polymer melt flowing through distribution holes C and the second fibers flowing through distribution holes D The ratio of the flow rate to the forming polymer melt is about 2:3 to 1:2, and finally, the first fiber-forming polymer and the second fiber-forming polymer in the single yarn extruded from the discharge hole n. The mass ratio to the fiber-forming polymer is 2:3 to 1:2,
In addition, the first fiber-forming polymer and the second fiber-forming polymer used in the present invention have different thermal shrinkage rates, and furthermore, the first fiber-forming polymer and the second fiber-forming polymer Because the two different heat shrinkage polymers are compatible or partially compatible after mixing, the presence of compatibility allows the Both formable polymer melts are extruded after being distributed in the manner of side-by-side composite spinning), and can be bonded together by such adhesion action and the action of different thermal contraction rates, Two types of polymer fibers (i.e., side-by-side composite single yarns of the second fiber-forming polymer/first fiber-forming polymer) extruded from the same discharge hole form a self-crimped configuration after being heat treated. Specifically, such a self-crimped form has a large heat shrinkage fiber-forming polymer inside the helical crimp and a heat shrinkage of a small fiber-forming polymer is on the outside of the helical crimp,
In the same fiber bundle, the combination of the first fiber-forming polymer and the second fiber-forming polymer in a portion of the second fiber-forming polymer/first fiber-forming polymer side-by-side composite single yarn. The mass ratio is from 3:2 to 2:1, and the second fiber-forming polymer/first fiber-forming polymer in the other part of the side-by-side composite single yarn and the first fiber-forming polymer Since the mass ratio with the second fiber-forming polymer is 2:3 to 1:2, there are certain differences in the crimp configuration of different single yarns, and such differences are pure secondary The fiber-forming polymer/first fiber-forming polymer side-by-side composite single yarn has an orderly left and right spiral configuration, and the produced side-by-side self-crimped elastic fiber relaxes. Since the crimp directions of the single yarns are randomly distributed after the heat treatment, random "striped unevenness" does not occur on the surface of the knitted fabric woven from the self-crimping elastic fibers.

Preferred technical means are as follows.

In the method for producing a side-by-side self-crimping elastic fiber described above, the mass ratio of the second fiber-forming polymer melt and the first fiber-forming polymer melt is 50:50.

In the method for producing a side-by-side self-crimping elastic fiber described above, the ejection hole m or the ejection hole n is a circular, elliptical, or "8"-shaped ejection hole. No special adjustment is required, and a common side-by-side composite discharge hole can be used to meet the requirements.

In the method for producing a side-by-side self-crimping elastic fiber described above, all the ejection holes are distributed concentrically, and the ejection holes in the same circle are all m or all n, whereby Y (or It ensures that X) is mixed in the middle of X (or Y) and acts to break down the formation of an orderly left-right helix.

In the method for producing a side-by-side self-crimping elastic fiber described above, the first fiber-forming polymer and the second fiber-forming polymer are made of the same material and have different viscosities, or The forming polymer and the second fiber-forming polymer are different in material quality, and there is inevitably a difference in thermal shrinkage between the polymers that satisfy these two conditions. can form a self-crimped form, and the material of the first fiber-forming polymer and the second fiber-forming polymer is polyester homopolymer, polyester copolymer, polyester modified product, polyamide It is selected from homopolymers, polyamide copolymers, and polyamide modification products.

In the above-described method for producing a side-by-side self-crimping elastic fiber, the discharge hole m is composed of a guide hole E, a transition hole, and a capillary hole which are connected in order, and the discharge hole n is composed of a guide hole F which is connected in order. , a transition hole, and a capillary hole, the guide hole E is connected to the distribution holes A and B at the same time, the guide hole F is connected to the distribution holes C and D at the same time, and the distribution holes A, Distribution hole B, distribution hole C, and distribution hole D are located in a distribution plate in spin beam III, and the second fiber-forming polymer melt is conveyed by spin beam I to distribution hole B and distribution hole D. and the first fiber-forming polymer melt is conveyed by the spinning beam II to the distribution holes A and C (the present invention uses the intrinsic viscosity of the first fiber-forming polymer melt, the second of the fiber-forming polymer melt, the temperature of spin beam I, the temperature of spin beam II, and the temperature of spin beam III cooperate with each other to form a second fiber at the entrance of distribution holes AD. the apparent viscosities of the liquid polymer melt and the first fiber-forming polymer melt are approximately the same).

In the method for producing a side-by-side self-crimping elastic fiber described above, the relaxation heat treatment temperature is 90 to 120° C. and the time is 20 to 30 minutes.

The present invention further provides a side-by-side self-crimped elastic fiber produced by the method for producing a side-by-side self-crimped elastic fiber according to any one of the above, wherein the side-by-side self-crimped elastic fiber comprises a plurality of Composed of a second fiber-forming polymer/first fiber-forming polymer side-by-side composite single yarn, in the same fiber bundle, the second fiber-forming polymer/first fiber-forming polymer The mass ratio of the first fiber-forming polymer to the second fiber-forming polymer in a portion of the side-by-side composite single yarn is 3:2 to 2:1, and the second fiber-forming polymer / The mass ratio of the first fiber-forming polymer and the second fiber-forming polymer in the other portion of the side-by-side composite single yarn of the first fiber-forming polymer is 2:3 to 1:2. Yes, after the side-by-side self-crimping elastic fiber is heat treated, the crimp direction of the single yarn is randomly distributed, and random distribution is a mathematical concept, that is, the crimp shape of each fiber is the same as that of other fibers. There is no "banding" in fabrics produced thereby.

(1) According to the method for producing a side-by-side self-crimping elastic fiber of the present invention, in the same fiber bundle, part of the side-by-side composite single yarn of the second fiber-forming polymer/first fiber-forming polymer The mass ratio of the first fiber-forming polymer to the second fiber-forming polymer in is 3:2 to 2:1, and the second fiber-forming polymer/first fiber-forming polymer The mass ratio of the first fiber-forming polymer and the second fiber-forming polymer in the other part of the side-by-side composite single yarn is 2:3 to 1:2, and the helical shape of each fiber after the relaxation heat treatment Since the crimped state is random, the crimped form of each fiber can be different from other fibers,
(2) According to the method for producing a side-by-side type self-crimped elastic fiber of the present invention, the side-by-side type self-crimped elastic fiber cannot form a regular arrangement of helical crimps, so that the side-by-side type conjugate fiber is knitted. solves the problem of "striped unevenness" formed in
(3) The side-by-side self-crimped elastic fiber produced by the method for producing a side-by-side self-crimped elastic fiber of the present invention has excellent elasticity, high overall performance, and a wider range of applications.

FIG. 1 is a schematic diagram of the melt distribution of the present invention, where A, B, C, D are independent distribution holes, and E, F are independent guide holes.

The invention will now be further described with reference to specific embodiments. It should be understood that these examples are intended to illustrate the invention and are not intended to limit the scope of the invention. Also, various changes or modifications to the invention may be made by those skilled in the art after reading the teachings of the invention, and the equivalents thereof are likewise limited by the claims of this application. It should be understood that this is included in the scope.

The crimp shrinkage rate and crimp stability of the present invention are obtained by testing the yarn bundle using GB6506-2001 <<Testing method for crimp performance of textured synthetic fiber yarn>>.
Tightening elongation (reflecting the elasticity and degree of crimping of the processed yarn, the fiber is first subjected to a light load and then to a heavy load, and the length difference value under two kinds of load and the crimp length ratio) and the test method for the crimp elastic recovery rate are as follows.

First, cut out two fiber samples with a length of about 50 cm, put them in hot water at 100 ° C. for 30 minutes, take them out and dry them naturally, cut out a sample with a length of about 30 cm, fix one end, A load of 0.0018 cN/dtex is applied to _one end for 30 s, a mark is made at 20 cm to obtain the initial length l1 of the sample, then a load of 0.09 cN/dtex is applied for 30 s, and the position of the mark is Measure to obtain the length l2 of the sample under heavy load, finally remove the heavy load, apply a load of 0.0018 cN/dtex for 30s after shrinking the sample for _2min without load, mark measured the position on the scale to obtain the length of recovery l3 _, the compression elongation (CE) and the crimp elastic recovery (SR) are calculated by the following equations.

In a method for producing side-by-side self-crimping elastic fibers, a PET melt (having an intrinsic viscosity of 0.6 dL/g) and a PA6 melt (having an intrinsic viscosity of 2.0 dL/g) in a weight ratio of 50:50 are used according to the FDY process. 2 dL/g), and then extruded from the discharge hole m (circular) and the discharge hole n (circular) in the same spinneret to produce FDY yarn, followed by relaxation heat treatment to produce side-by-side self-crimped elastic fibers. Get,
The PA6 melt and the PET melt each contain 5 wt% PET-PA6 copolymer melt. After mixing with PA6 at a mass ratio of 1: 1, the temperature is 273 ° C. and the degree of vacuum is 45 Pa for 60 minutes to polycondensate,
The distribution means distributing the PA6 melt through the distribution hole A and the PET melt through the distribution hole B to the discharge hole m, and the PA6 melt through the distribution hole C and the PET melt. Refers to distribution to discharge hole n through distribution hole D. At the entrances of distribution hole A, distribution hole B, distribution hole C, and distribution hole D, the difference in apparent viscosity between the PET melt and the PA6 melt is , 5%, and
Distribution hole A and distribution hole B are cylindrical holes of the same height, the diameter ratio of distribution hole A and distribution hole B is 1.10:1, distribution hole C and distribution hole D are , are cylindrical holes of the same height, and the ratio of the diameters of the distribution holes C and D is 1:1.10,
all the outlet holes are distributed concentrically and the outlet holes in the same circle are either all m or all n;
As shown in FIG. 1, a discharge hole m is composed of a guide hole E, a transition hole and a capillary pore connected in sequence, and a discharge hole n is composed of a guide hole F, a transition hole and a capillary pore connected in sequence. The guide hole E is connected to the distribution hole A and the distribution hole B at the same time, the guide hole F is connected to the distribution hole C and the distribution hole D at the same time, and the distribution hole A, the distribution hole B, the distribution hole C , and distribution holes D are located in the distribution plate in spin beam III, the PET melt is conveyed by spin beam I to distribution holes B and D, and the PA6 melt is conveyed by spin beam II to distribution holes A and conveyed to the distribution hole C,
The temperature of spinning beam I is 285° C., the temperature of spinning beam II is 270° C., the temperature of spinning beam III is 282° C.,
The parameters of the FDY process are: the cooling temperature is 25°C, the network pressure is 0.2 MPa, the speed of the first roller is 1600 m/min, the temperature of the first roller is 80°C, the second The speed of the second roller is 2760 m/min, the temperature of the second roller is 140° C., the winding speed is 2710 m/min, the temperature of the relaxation heat treatment is 104° C., and the time is 30 min.

The finally produced side-by-side self-crimping elastic fiber is composed of a plurality of PA6/PET side-by-side composite single yarns, and the crimp directions of the single yarns in the side-by-side self-crimping elastic fiber are randomly distributed. The type self-crimped elastic fiber has a crimp shrinkage rate of 52%, a crimp stability of 80%, a tightening elongation rate of 88%, a crimp elastic recovery rate of 93%, and a side-by-side type. The self-crimping elastic fibers have a breaking strength of ≧2.5 cN/dtex, a breaking elongation of 50.5% and a total fineness of 100 dtex.

The side-by-side type self-crimping elastic fibers produced above were manufactured into a knitted fabric and tested for striped unevenness. The D-value is 0.57%, which explains the absence of the "stripe" problem in the side-by-side self-crimping elastic fibers made in the present invention.

In a method for producing side-by-side self-crimping elastic fibers, a PET melt (having an intrinsic viscosity of 0.63 dL/g) and a PA6 melt (having an intrinsic viscosity of 2 dL/g) in a weight ratio of 50:50 are used according to the FDY process. g) is distributed, and then extruded from the outlet hole m (oval) and outlet hole n (“8” shape) in the same spinneret to produce FDY yarn, followed by relaxation heat treatment, and side-by-side self-crimping elastic get fiber
The PA6 melt and the PET melt each contained 5 wt% PET-PA6 copolymer melt, and in the process of making the PET-PA6 copolymer, PET with a number average molecular weight of 2500 and PET with a number average molecular weight of 2500 After mixing with PA6 at a mass ratio of 1: 1, the temperature is 275 ° C. and the degree of vacuum is 45 Pa for 55 minutes for polycondensation reaction,
The distribution means distributing the PA6 melt through the distribution hole A and the PET melt through the distribution hole B to the discharge hole m, and the PA6 melt through the distribution hole C and the PET melt. Refers to distribution to discharge hole n through distribution hole D. At the entrances of distribution hole A, distribution hole B, distribution hole C, and distribution hole D, the difference in apparent viscosity between the PET melt and the PA6 melt is , 2.8%, and
Distribution hole A and distribution hole B are cylindrical holes with the same height, the diameter ratio of distribution hole A and distribution hole B is 1.18:1, distribution hole C and distribution hole D are , are cylindrical holes of the same height, and the ratio of the diameters of the distribution holes C and D is 1:1.18,
all the outlet holes are distributed concentrically and the outlet holes in the same circle are either all m or all n;
The discharge hole m is composed of a guide hole E, a transition hole, and a capillary hole connected in order, and the discharge hole n is composed of a guide hole F, a transition hole, and a capillary hole connected in order, and a guide hole E is connected to distribution hole A and distribution hole B at the same time, guide hole F is connected to distribution hole C and distribution hole D at the same time, distribution hole A, distribution hole B, distribution hole C, and distribution hole D are: Located at the distribution plate in spin beam III, the PET melt is conveyed by spin beam I to distribution holes B and D, and the PA6 melt is conveyed to distribution holes A and C by spin beam II. ,
The temperature of spinning beam I is 283° C., the temperature of spinning beam II is 265° C., the temperature of spinning beam III is 282° C.,
The parameters of the FDY process are: cooling temperature is 23°C, network pressure is 0.24MPa, speed of the first roller is 1550m/min, temperature of the first roller is 80°C, second The speed of the second roller is 2800 m/min, the temperature of the second roller is 144° C., the winding speed is 2670 m/min, the temperature of the relaxation heat treatment is 90° C., and the time is 24 min.

The finally produced side-by-side self-crimping elastic fiber is composed of a plurality of PA6/PET side-by-side composite single yarns, and the crimp directions of the single yarns in the side-by-side self-crimping elastic fiber are randomly distributed. The type self-crimped elastic fiber has a crimp shrinkage rate of 51.5%, a crimp stability of 77.3%, a straining elongation rate of 87.9%, and a crimp elastic recovery rate of 92%. 8%, and the side-by-side self-crimping elastic fiber has a breaking strength of ≧2.5 cN/dtex, a breaking elongation of 57%, and a total fineness of 95 dtex.

The side-by-side type self-crimping elastic fibers produced above were manufactured into a knitted fabric and tested for striped unevenness. The D-value is 0.24%, which explains the absence of the "stripe" problem in the side-by-side self-crimping elastic fibers made according to the invention.

In a method for producing side-by-side self-crimping elastic fibers, according to the POY-DT process, a PET melt (having an intrinsic viscosity of 0.55 dL/g) and a PBT melt (having an intrinsic viscosity of 1.1 dL/g), and then extruded from the discharge hole m (circular) and discharge hole n (elliptical) in the same spinneret to produce POY-DT yarn, followed by relaxation heat treatment, side-by-side self obtaining crimped elastic fibers,
The distribution means that the PBT melt is distributed through the distribution hole A, the PET melt is distributed through the distribution hole B to the discharge hole m, the PBT melt is distributed through the distribution hole C, and the PET melt is distributed. Refers to distribution to discharge hole n through distribution hole D. At the entrances of distribution hole A, distribution hole B, distribution hole C, and distribution hole D, the difference in apparent viscosity between the PET melt and the PBT melt is , 4.9%, and
Distribution hole A and distribution hole B are cylindrical holes of the same height, the diameter ratio of distribution hole A and distribution hole B is 1.15:1, distribution hole C and distribution hole D are , are cylindrical holes of the same height, and the ratio of the diameters of the distribution holes C and D is 1:1.15,
all the outlet holes are distributed concentrically and the outlet holes in the same circle are either all m or all n;
The discharge hole m is composed of a guide hole E, a transition hole, and a capillary hole connected in order, and the discharge hole n is composed of a guide hole F, a transition hole, and a capillary hole connected in order, and a guide hole E is connected to distribution hole A and distribution hole B at the same time, guide hole F is connected to distribution hole C and distribution hole D at the same time, distribution hole A, distribution hole B, distribution hole C, and distribution hole D are: Located at the distribution plate in spinning beam III, the PET melt is conveyed by spinning beam I to distribution holes B and D, and the PBT melt is conveyed to distribution holes A and C by spinning beam II. ,
The temperature of spinning beam I is 280° C., the temperature of spinning beam II is 260° C., the temperature of spinning beam III is 276° C.,
The parameters of the POY-DT process are: cooling temperature is 23° C., winding speed is 2800 m/min, setting temperature is 133° C., stretching temperature is 95° C., and stretching ratio is 1.8. ,
The relaxation heat treatment temperature is 90° C. and the time is 30 min.

The finally produced side-by-side self-crimping elastic fiber is composed of a plurality of PBT/PET side-by-side composite single yarns, and the crimp directions of the single yarns in the side-by-side self-crimping elastic fiber are randomly distributed. The type self-crimped elastic fiber has a crimp shrinkage rate of 66%, a crimp stability of 92.3%, a straining elongation rate of 114%, and a crimp elastic recovery rate of 80%. It has a breaking strength of 3.07 cN/dtex, a breaking elongation of 47%, and a total fineness of 80 dtex.

A method for producing a side-by-side self-crimping elastic fiber, the process of which is as follows.

Depending on the POY process, the same A side-by-side type self-crimping elastic fiber is obtained by extruding from an ejection hole m (circular) and an ejection hole n (circular) in a spinneret,
The distribution means that the PBT melt is distributed through the distribution hole A, the PTT melt is distributed through the distribution hole B to the discharge hole m, the PBT melt is distributed through the distribution hole C, and the PTT melt is distributed. Refers to distribution to discharge hole n through distribution hole D, and at the inlets of distribution hole A, distribution hole B, distribution hole C, and distribution hole D, the difference in apparent viscosity between the PTT melt and the PBT melt is , 5%, and
The distribution holes A and B are cylindrical holes with the same height, the diameter ratio of the distribution holes A and B is 1.1:1, and the distribution holes C and D are , are cylindrical holes of the same height, and the ratio of the diameters of the distribution holes C and D is 1:1.1,
The discharge hole m is composed of a guide hole E, a transition hole, and a capillary hole connected in order, and the discharge hole n is composed of a guide hole F, a transition hole, and a capillary hole connected in order, and a guide hole E is connected to distribution hole A and distribution hole B at the same time, guide hole F is connected to distribution hole C and distribution hole D at the same time, distribution hole A, distribution hole B, distribution hole C, and distribution hole D are: Located at the distribution plate in spinning beam III, the PTT melt is conveyed by spinning beam I to distribution holes B and D, and the PBT melt is conveyed to distribution holes A and C by spinning beam II. , the temperature of spinning beam I is 255° C., the temperature of spinning beam II is 266° C., the temperature of spinning beam III is 265° C.,
all the outlet holes are distributed concentrically and the outlet holes in the same circle are either all m or all n;
The POY process parameters are a cooling temperature of 24° C., a winding speed of 2660 m/min,
The produced side-by-side type self-crimping elastic fibers are composed of a plurality of PBT/PTT side-by-side composite single yarns, and the single yarn crimp directions of the DT fibers produced by the side-by-side type self-crimping elastic fibers are randomly distributed. , the crimp shrinkage rate is 70%, the crimp stability is 93.3%, the tightening elongation rate is 113%, the crimp elastic recovery rate is 85%, and the side-by-side self-crimping elastic fiber has a breaking strength of 2.29 cN/dtex, a breaking elongation of 125%, a single yarn fineness of 0.5 dtex, and a total fineness of 110 dtex.

In a method for producing side-by-side self-crimping elastic fibers, according to the POY-DT process, a PET melt (having an intrinsic viscosity of 0.52 dL/g) and a PBT melt (having an intrinsic viscosity of 1.14 dL / g), extruded from the discharge hole m (circular) and the discharge hole n (circular) in the same spinneret to produce POY-DT yarn, followed by relaxation heat treatment, side-by-side self-winding obtaining elastic fibers,
The distribution means that the PBT melt is distributed through the distribution hole A, the PET melt is distributed through the distribution hole B to the discharge hole m, the PBT melt is distributed through the distribution hole C, and the PET melt is distributed. Refers to distribution to discharge hole n through distribution hole D. At the entrances of distribution hole A, distribution hole B, distribution hole C, and distribution hole D, the difference in apparent viscosity between the PET melt and the PBT melt is , 5%, and
Distribution hole A and distribution hole B are cylindrical holes with the same height, the diameter ratio of distribution hole A and distribution hole B is 1.17:1, distribution hole C and distribution hole D are , are cylindrical holes of the same height, and the ratio of the diameters of the distribution holes C and D is 1:1.17,
all the outlet holes are distributed concentrically and the outlet holes in the same circle are either all m or all n;
The discharge hole m is composed of a guide hole E, a transition hole, and a capillary hole connected in order, and the discharge hole n is composed of a guide hole F, a transition hole, and a capillary hole connected in order, and a guide hole E is connected to distribution hole A and distribution hole B at the same time, guide hole F is connected to distribution hole C and distribution hole D at the same time, distribution hole A, distribution hole B, distribution hole C, and distribution hole D are: Located at the distribution plate in spinning beam III, the PET melt is conveyed by spinning beam I to distribution holes B and D, and the PBT melt is conveyed to distribution holes A and C by spinning beam II. ,
The temperature of spinning beam I is 279° C., the temperature of spinning beam II is 261° C., the temperature of spinning beam III is 277° C.,
The parameters of the POY-DT process are: cooling temperature is 25°C, winding speed is 3100m/min, setting temperature is 134°C, stretching temperature is 89°C, and stretching ratio is 1.7. ,
The relaxation heat treatment temperature is 98° C. and the time is 27 min.

The finally produced side-by-side self-crimping elastic fiber is composed of a plurality of PBT/PET side-by-side composite single yarns, and the crimp directions of the single yarns in the side-by-side self-crimping elastic fiber are randomly distributed. The type self-crimped elastic fiber has a crimp shrinkage rate of 67%, a crimp stability of 92.6%, a straining elongation rate of 114%, and a crimp elastic recovery rate of 80%. It has a breaking strength of 3.02 cN/dtex, a breaking elongation of 51%, and a total fineness of 140 dtex.

In a method for producing side-by-side self-crimping elastic fibers, according to the POY-DT process, a PET melt (having an intrinsic viscosity of 0.51 dL/g) and a PBT melt (having an intrinsic viscosity of 1.14 dL / g), extruded from the discharge hole m (circular) and the discharge hole n (circular) in the same spinneret to produce POY-DT yarn, followed by relaxation heat treatment, side-by-side self-winding obtaining elastic fibers,
The distribution means that the PBT melt is distributed through the distribution hole A, the PET melt is distributed through the distribution hole B to the discharge hole m, the PBT melt is distributed through the distribution hole C, and the PET melt is distributed. Refers to distribution to discharge hole n through distribution hole D. At the entrances of distribution hole A, distribution hole B, distribution hole C, and distribution hole D, the difference in apparent viscosity between the PET melt and the PBT melt is , 4.4%, and
Distribution hole A and distribution hole B are cylindrical holes with the same height, the diameter ratio of distribution hole A and distribution hole B is 1.18:1, distribution hole C and distribution hole D are , are cylindrical holes of the same height, and the ratio of the diameters of the distribution holes C and D is 1:1.18,
all the outlet holes are distributed concentrically and the outlet holes in the same circle are either all m or all n;
The discharge hole m is composed of a guide hole E, a transition hole, and a capillary hole connected in order, and the discharge hole n is composed of a guide hole F, a transition hole, and a capillary hole connected in order, and a guide hole E is connected to distribution hole A and distribution hole B at the same time, guide hole F is connected to distribution hole C and distribution hole D at the same time, distribution hole A, distribution hole B, distribution hole C, and distribution hole D are: Located at the distribution plate in spinning beam III, the PET melt is conveyed by spinning beam I to distribution holes B and D, and the PBT melt is conveyed to distribution holes A and C by spinning beam II. ,
The temperature of spinning beam I is 279° C., the temperature of spinning beam II is 260° C., the temperature of spinning beam III is 274° C.,
The parameters of the POY-DT process are: cooling temperature is 25°C, winding speed is 2840m/min, setting temperature is 135°C, stretching temperature is 95°C, and stretching ratio is 1.7. ,
The relaxation heat treatment temperature is 101° C. and the time is 26 min.

The finally produced side-by-side self-crimping elastic fiber is composed of a plurality of PBT/PET side-by-side composite single yarns, and the crimp directions of the single yarns in the side-by-side self-crimping elastic fiber are randomly distributed. The type self-crimped elastic fiber has a crimp shrinkage rate of 68%, a crimp stability of 92.9%, a straining elongation rate of 115%, and a crimp elastic recovery rate of 82%. It has a breaking strength of 3.04 cN/dtex, a breaking elongation of 49%, and a total fineness of 90 dtex.

Claims (8)

Depending on the specific spinning process, the first fiber-forming polymer melt and the second fiber-forming polymer melt are distributed and then extruded through outlet holes m and n in the same spinneret, side-by-side Producing self-crimping elastic fibers,
The distribution means distributing the first fiber-forming polymer melt through the distribution hole A and the second fiber-forming polymer melt through the distribution hole B to the discharge hole m, means to distribute the fiber-forming polymer melt of through the distribution hole C and the second fiber-forming polymer melt through the distribution hole D to the discharge hole n,
the first fiber-forming polymer and the second fiber-forming polymer are compatible or partially compatible,
At the inlets of distribution hole A, distribution hole B, distribution hole C, and distribution hole D, the difference in apparent viscosity between the second fiber-forming polymer melt and the first fiber-forming polymer melt is 5. % or less,
Distribution hole A and distribution hole B are cylindrical holes with the same height, and the diameter ratio of distribution hole A and distribution hole B is 1.10 to 1.20:1. the distribution hole D is a cylindrical hole with the same height, the ratio of the diameters of the distribution hole C and the distribution hole D is 1:1.10-1.20;
Said specific spinning process is POY process, FDY process, POY-DTY process or POY-DT process, and after finishing said POY process, said FDY process and said POY-DT process, the fiber is further subjected to a relaxation heat treatment. characterized by
A method for producing a side-by-side self-crimping elastic fiber. characterized in that the mass ratio of the second fiber-forming polymer melt to the first fiber-forming polymer melt is 50:50,
The method for producing a side-by-side self-crimping elastic fiber according to claim 1. The outlet hole m or the outlet hole n is a circular, elliptical or "8" shaped outlet hole,
The method for producing a side-by-side self-crimping elastic fiber according to claim 1. All the outlet holes are distributed concentrically, and the outlet holes in the same circle are either all m or all n,
The method for producing a side-by-side self-crimping elastic fiber according to claim 1. The first fiber-forming polymer and the second fiber-forming polymer have the same material and different viscosities, or the first fiber-forming polymer and the second fiber-forming polymer have different viscosities. are different in material, and the materials of the first fiber-forming polymer and the second fiber-forming polymer are polyester homopolymer, polyester copolymer, polyester modified product, polyamide homopolymer, polyamide selected from copolymers and polyamide modified products,
The method for producing a side-by-side self-crimping elastic fiber according to claim 1. The discharge hole m is composed of a guide hole E, a transition hole, and a capillary hole connected in order, and the discharge hole n is composed of a guide hole F, a transition hole, and a capillary hole connected in order, and a guide hole E is connected to distribution hole A and distribution hole B at the same time, guide hole F is connected to distribution hole C and distribution hole D at the same time, distribution hole A, distribution hole B, distribution hole C, and distribution hole D are: Located at the distribution plate in spin beam III, the second fiber-forming polymer melt is conveyed by spin beam I to distribution holes B and D, and the first fiber-forming polymer melt is conveyed by the spinning beam II to the distribution holes A and C, characterized in that
The method for producing a side-by-side self-crimping elastic fiber according to claim 1. The temperature of the relaxation heat treatment is 90 to 120 ° C., and the time is 20 to 30 min,
The method for producing a side-by-side self-crimping elastic fiber according to claim 1. A side-by-side self-crimping elastic fiber produced by the method for producing a side-by-side self-crimping elastic fiber according to any one of claims 1 to 7,
Composed of a plurality of side-by-side composite single yarns of the second fiber-forming polymer/first fiber-forming polymer, and in the same fiber bundle, the second fiber-forming polymer/first fiber-forming polymer The mass ratio of the first fiber-forming polymer to the second fiber-forming polymer in a portion of the combined side-by-side composite single yarn is 3:2 to 2:1, and the second fiber-forming polymer is The mass ratio of the first fiber-forming polymer to the second fiber-forming polymer in the other part of the coalescing/first fiber-forming polymer side-by-side composite single yarn is 2:3 to 1:2. characterized by
Side-by-side self-crimping elastic fiber.

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