JPH04222241A - Production of processed yarn having double-layer structure and composed of ultra-fine fiber - Google Patents

Abstract

PURPOSE:To provide a false-twisted processed yarn having double-layer structure, soft feeling, high drapeability and excellent stiffness and body suitable for women's wear and children's wear. CONSTITUTION:The objective false-twisted processed yarn having double-layer structure is produced by using an undrawn filament A having a birefringence DELTAnA of <=60X10<-3> and an undrawn filament B having a birefringence DELTAnB of 10X10<-3> to 70X10<-3> as raw materials and carrying out the drawing and false- twisting of the filaments under a condition to prevent the agglutination or fusion of both filaments and to get a filament A fineness of <=1.5de and a filament B fineness of >=2.0de after false-twisting.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a two-layer textured yarn made of ultrafine yarn.

0002

[Prior Art] As a prior art, the difference in [η] of polymers,
Spinning speed difference, fiber denier difference, feeding speed difference (tension difference),
Covering yarns that have a two-layer structure of a core and sheath by twisting, false twisting, air entanglement, etc. by utilizing heat shrinkage difference are known. In particular, as a method for producing a two-layer textured yarn by false twisting that is related to the present invention, two or more types of undrawn yarns having a difference in elongation at break of 100% or more are simultaneously false-twisted, for example, as disclosed in Japanese Patent Publication No. 53-44577. Method for obtaining processed yarn with uneven thickness, JP-A-49-
A method of drawing and false twisting two or more types of undrawn yarns having a Δn difference of around 5×10-3 such as No. 102915 at a specific stretching ratio;
A method of simultaneously drawing and false twisting undrawn yarns with a difference of 30×10 −3 or less, and furthermore, JP-A-50-13652, JP-A-52
There is a method of false twisting an undrawn yarn having a Δn of 20×10 −3 or more, such as -27823, and a drawn yarn. However, in all of these methods, the single yarn denier after false twisting is thick, such as 1.5 dr or more, or fusion occurs between filaments, resulting in uneven thickness (thread lines), so the resulting fabric is tends to become rough and hard. In addition, when the difference in Δn is large, there is a problem that the yarn length difference between the core yarn and the covering yarn is large under normal false twisting conditions, and the passability of processes such as additional twisting, weaving, knitting and weaving is likely to be poor. There has been no method for obtaining a double-layered false twisted yarn with good process passability in which the thick drier core yarn is almost uniformly covered. On the other hand, Japanese Patent Publication No. 48-23968 and Japanese Patent Publication No. 52-189
As seen in 68, the single yarn has a fine dr of 1.0 dr or less and 1
．． False twisted fibers with a thick dr of 0 dr or more are also known, but these do not have a two-layer structure due to no or small difference in Δn, resulting in a problem of loss of flexibility. Furthermore, false twisting of only ultra-fine yarns tends to cause single yarn breakage, and the resulting fabric is flexible, but does not have tension or stiffness, and is made by combining and twisting fine dred false twisted yarns and thick dredged false twisted yarns to create a two-layered yarn. In this case, the high cost and color difference cause patter and irritation.

[0003] Based on the above background, the present inventors have carried out intensive research in an effort to obtain a double-layered false-twisted yarn with the aim of producing wool-like fabrics that have a soft, slimy feel, appropriate tension, elasticity, and bulkiness. Patent Application No. 159702 (1982)
57730) proposed a two-layer textured yarn. However, since this yarn has a core yarn twist of 100T/M or more, it is suitable for men's clothing that requires a firm waist, but it is still insufficiently flexible to be applied to women's and children's clothing. Was. The present invention has discovered a method for producing a two-layer textured yarn suitable for women's wear and children's wear that requires soft drapability by setting the first twist of the core yarn to 80 T/M or less.

0004

Problems to be Solved by the Invention The present invention has a single yarn fineness of 2.
A double-layered false-twisted structure that does not contain any glued or fused parts, with a multifilament of 0 denier (hereinafter abbreviated as dr) or more serving as the core yarn, and an extra-fine multifilament with a single yarn fineness of 1.5dr or less covering the outside. The present invention provides a method for producing yarn, and attempts to use the processed yarn to obtain fabrics with unprecedented high added value that have ultra-fine, flexible surface touch, appropriate tension, elasticity (resilience), and bulkiness. It is something.

[0005]

[Means for Solving the Problems] That is, the present invention provides a two-layered false twisted yarn made of thermoplastic synthetic fibers,
Multifilament A consisting of filaments with a single yarn fineness of 1.5 denier or less has a mixing ratio of 30 to 80% by weight and is substantially untwisted or has a first twist of 80 T/M or less and has a single yarn fineness of 2.0 denier or more The present invention relates to a process for producing a two-layer structured processed yarn made of ultrafine yarns, which covers multifilament B consisting of filaments of 7 to 30% with a yarn length difference of 7 to 30%, and which does not contain any glued or fused portions.

The manufacturing method is such that the difference in birefringence ΔnB - ΔnA between filaments A and B is 8×10 −3 to 40×10
-2 or more undrawn filaments of 3 are drawn and false twisted under the following specific conditions to prevent filament B from being pre-twisted at 80T/M or less, or to avoid pulling them together and causing agglutination or fusion. It is something to do.

[0007]

[Math 2]

Furthermore, in these manufacturing methods, it is desirable to twist the filaments A and B together at 80 T/M or less and then false twist them. Furthermore, in the processed yarn of the present invention and its manufacturing method, the single yarn fineness of filaments A and B after false twisting is preferably 1.0 dr or less and 3.0 dr or more, respectively.
Polyester is suitable as the fiber.

The present invention will be explained in detail below. The thermoplastic synthetic fibers referred to in the present invention refer to polyester-based, polyamide-based, polyacrylonitrile-based, polyvinyl-based, and polyurethane-based fibers, including those copolymerized with modifying components, matting agents, heat stabilizers, and pigments. , antistatic property improvers, flame retardant property improvers, etc. are also included. In particular, polyester in which 80% or more of the repeating units are polyethylene terephthalate is preferred from the viewpoint of product properties, and the filaments A and B may be composed of the same type of polymer or two or more types of polymers.

[0010] The ultrafine multifilament A having a single filament fineness of 1.5 dr or less used in the present invention includes fibers with a circular or irregular cross section obtained by ordinary spinning techniques, and in order to obtain a soft touch, preferably 1. It is 0 dr or less, particularly preferably 0.3 to 0.8 dr. On the other hand, in order to impart appropriate repulsion and bulkiness to the fabric, filament B, which is a core yarn, has a single yarn fineness of 2.0 dr or more, preferably 3 after false twisting.
~8 dr, and the mixing ratio of filament B is ~30
It should be 80% by weight, preferably 50-70% by weight. Here, if the mixing ratio of filament B is less than 30% by weight, the repellency of the fabric will decrease, and if it exceeds 80% by weight, the fabric will have a strong rough and hard feel, both of which will reduce the commercial value.

Furthermore, in the present invention, it is preferable to first twist the filament B at 80 T/M or less in order to improve processability and repulsion. If the filament B is pre-twisted at more than 80 T/M, the difference in yarn length is too large, causing slack in the side yarns, resulting in poor process passability and an increase in cost, which is undesirable. Also, filaments A and B are 80T/
M or less may be used, but if it exceeds 80 T/M, the covering properties of the filament A will deteriorate and the cost will increase, which is not preferable.

[0012] In order to obtain an ultrafine covering yarn having no adhesive or fused portions and having good processability in the present invention, one or more filaments A and B have different birefringence ΔnA and ΔnB. Moreover, simultaneous false twisting is required under limited conditions. That is, ΔnA must be 60×10 −3 or less, ΔnB must be 10×10 −3 to 70×10 −3 , and 8×10 −3 ≦ΔnB − ΔnA ≦40×10 −3 . However, ΔnA or ΔnB means the average birefringence when filament A or B is composed of one type, and Δn when it is composed of two or more types.
nA means the average birefringence of the lowest group in filament A, and ΔnB means the average birefringence of the highest group in filament B. ΔnA is 60×10-3
If it exceeds 1.5dr, it means high-speed spinning of 1.5 dr or less of single yarn, which makes spinning difficult and tends to cause winding of single yarn. Preferably Δn
A is 5×10 −3 to 30×10 −3 .

On the other hand, when ΔnB is less than 10×10−3, Δ
Since the value of nB - ΔnA is small and the difference in elongation between filaments A and B is small, the difference in yarn length between filaments B and A decreases, resulting in a decrease in the covering property of filament A, and as a result, the core yarn appears on the fabric surface. Impairs soft touch. In addition, when ΔnB exceeds 70×10-3, it means ultra-high speed spinning, which makes spinning difficult and increases cost.
Furthermore, the value of ΔnB - ΔnA increases, the yarn length difference increases, and the filament A becomes more slack (looped), resulting in poor additional twisting and process passability of the knitting machine. Preferably ΔnB is 15×10 −3 to 40×10 −3 . Due to the above yarn length difference, the value of ΔnB - ΔnA is 8×10
-3 to 40 x 10-3 preferably 10 x 10-3 to 25
×10-3. Here, the birefringence Δn is the interference fringe (n) due to the degree of orientation of the polymer molecular chains, the retardation (r) determined by Berek's compensator for orientation that does not result in interference fringes, the fiber diameter (d), and the light source. From the wavelength of the sodium D line (λ=589 mμ), Δn=(n・λ+r
)/d, but it is usually 5 x 10-3 between the same samples.
In this invention, the number of measurements is limited to 10 to prevent variations in the front and back.
The average value was used for more than 10 times.

Furthermore, in the first manufacturing method, it is necessary to perform the false twisting under the above-mentioned false twisting conditions [A] to [C]. False twist number S(T
/M), total yarn denier Dr, drawing ratio DR, and yarn length difference (ΔnB - ΔnA)/ΔnB, which is expressed in the range of formula [A], and outside this range S
If S is large, yarn breakage occurs and false twisting is difficult, and if S is small, the tension before false twisting is high and untwisting causes sticking, which tends to result in a coarse and hard fabric with poor bulk. The stretching ratio DR is expressed by the formula [B] and must be within the shaded range in FIG. Filament B, which has a high birefringence ΔnB, has low elongation, and above the DR range, filament B tends to break, making false twisting difficult. Below this range, the false-twisting tension fluctuates greatly and untwisting occurs, resulting in a coarse and hard false-twisted yarn with uneven thickness. In addition, in the present invention, the false twisting temperature is set to [C
] By regulating as shown in the formula, it is possible to obtain an ultra-fine covered yarn that does not cause fusion or stuck portions in the filaments and has good crimp fastness.

In the present invention, the yarn may be further passed through a heater after false twisting to be used as a two-stage heater-set yarn, or additional twisting may be applied after false twisting to improve process passability and fiber blending.

FIGS. 2 and 3 show an example of the cross section and side surface of the ultrafine fiber covering yarn obtained according to the present invention.
Single yarn 1.
The filament A of 5 dr or less covers almost uniformly without adhesion or fusion, and has a bulky thread form as a whole. In addition, adhesion or fusion as used in the present invention means a state in which the single fibers cannot be easily separated by hand without cutting them, and if pseudo-adhesion or thick drizzle appears partially on the outside, it is difficult to separate the single fibers. Included in invention. Then, if necessary, the covering yarn of the ultrafine fibers is additionally twisted or combined with other fibers to form a fabric such as a knitted fabric, a woven fabric, or a nonwoven fabric using a conventional method. Although some other fibers may be used when constructing the fabric, it is more preferable that the false twisted yarn according to the present invention covers the surface of the fabric. The fabric of the false twisted yarn obtained by the present invention is as follows:1.
The ultra-fine threads with 5 dr or less appear on the surface and have a soft, slimy feel, and the thick dr with 2.0 dr or more improves repulsion and bulk, making it a high value-added product never seen before.

[0017]

[Examples] The present invention will be specifically explained below with reference to Examples. Example 1 and Comparative Examples 1 and 2 [η] = 0.65 dl/g (Intrinsic viscosity measured using an Upperohde viscometer in a constant temperature bath at 30°C using a mixed solvent of equal amounts of phenol and tetrachloroethane is 0. 65dl/
The polyethylene terephthalate g) was spun using a conventional method to obtain filament A (120 dr/72f) with an average birefringence ΔnA of 13×10−3 and ΔnB of 25×10−3.
An undrawn yarn of filament B (218 dr/32 f) was obtained. Next, both undrawn filaments were aligned and drawn and false twisted under the conditions shown in Table 1. Also, as Comparative Example 1, ΔnB=1
Undrawn yarn of 240 dr/32f of 8×10-3, 165 dr/32f of ΔnB=59×10-3 as comparative example 2
The undrawn yarns were aligned with the 120 dr/72 f filament A and drawn and false twisted under the conditions shown in Table 1. The mixing ratio of filament B was 58.1% in Example 1 and Comparative Example 1.
was 64.3%, and Comparative Example 2 was 47.2%. Next, two of each of the three types of false twisted yarns were twisted at 300T/M.
After additional twisting, use 1/1 for warp and weft yarns.
I created a flat textile. Table 1 also lists the yarn physical properties, process passability, and fabric texture results of the three types of false twisted yarns.

[0018]

[Table 1]

Yarn length difference: After separating the outer filament A of filament B with a yarn length of 20 cm under an initial load of 0.2 g/dr, the following formula is obtained from the yarn length LA of filament A under a load of 0.2 g/dr. Calculated as (LA-20)/20 x 100 (%) The difference in birefringence ΔnB - ΔnA of the birefringence between filaments A and B for the false twisted yarn obtained in Example 1 was 12 x 10 -3 under the false twisting conditions in Table 1. The yarn length difference was 14.5%, the yarn had a complete two-layer structure as shown in FIGS. 2 and 3, and there was no sticking. In addition, the additional twisting and weaving processes were trouble-free, and the resulting fabric had a single outer thread d
It combines the soft sliminess of r0.80 with the bulkiness and repulsion of single core yarn dr3.4, making it an unprecedented high-quality wool fabric.

On the other hand, in Comparative Example 1, ΔnB−ΔnA=5×1
Since the yarn length was 0-3, the yarn length difference was as small as 5.0%, and the covering property of the ultrafine yarn was decreased, the yarn became coarse and hard, and the bulkiness was also slightly decreased. On the other hand, in Comparative Example 2, ΔnB - ΔnA = 46 × 10 -3, which is too large, the yarn length difference was 31.7%, and the side yarns became slack during additional twisting, resulting in poor passability in some places. There were threads (slabs) in the fabric, which degraded the appearance of the resulting fabric. In Example 1, where the draw ratio was increased to 2.8 times, single yarn breakage occurred, and at 1.5 times, the false twisting tension was low and untwisting occurred, resulting in hard false twisted yarns with partial sticking.

Example 2 As filament A, ΔnA=15×10-3 and 50d
Using undrawn thread of r/36f nylon 6, filament B is 110dr/16f with ΔnB=48×10−3.
Using undrawn polyester yarn, both filaments were doubled together and first twisted at 80T/M in the Z direction, and then simultaneously false twisted under the following conditions. Stretching ratio: 1.6 times, heater temperature: 1
45℃, number of false twists: 2,500T/M, winding speed: 200
m/min. The obtained false twisted yarn had a yarn length difference of 11% at 115 dr/52 f, the ultrafine nylon 6 yarn almost completely covered the thick polyester dr yarn, and there was no sticking. A single tricot knit of 28G with a 1/3 satin structure was constructed by using the false twisted yarn as the front yarn and high shrinkage polyester filament 50dr/24f with a hot water shrinkage rate of 25% as the back yarn. Thereafter, the fabric was relaxed (hot water treated) and dyed with an acid dye and a disperse dye to sufficiently shrink the back yarn and make the front yarn stand out on the surface of the knitted fabric. The resulting tricot knit has a soft surface touch, repellency, and drapability, and has become a reversible, high-value-added product with different hues on the front and back sides.

[Brief explanation of the drawing]

[Fig. 1] Fig. 1 shows the relationship between the birefringence ΔnB of undrawn filament B (core yarn) and the draw ratio DR during false twisting in the above-mentioned manufacturing method of the present invention. Indicate the scope of the invention. However, when there are two or more types of filaments B, ΔnB represents the average birefringence of the highest group.

FIG. 2 shows a cross-sectional view of the ultrafine fiber covering yarn obtained by the present invention, and the one with a large cross-sectional area or the thick line in the figure means filament B with a single yarn of 2.0 dr or more, It means a filament A with a small cross-sectional area or a single filament of 1.5 dr or less. However, in the present invention, the ultrafine fibers do not completely cover the thick dr.
This also includes the case where r is present on the outside and the case where the single fibers are stuck to each other but are pseudo-sticky and can be easily separated by hand.

FIG. 3 is a side view of the ultrafine covering yarn obtained according to the present invention.

Claims (4)

[Claims] 1. Undrawn filaments A having a birefringence ΔnA of 60×10 −3 or less and undrawn filaments having a birefringence ΔnB of 10×10 −3 to 70×10 −3 which are thermoplastic synthetic fibers. B is 8×10-3≦ΔnB−Δn
A≦40×10-3, and filament B has a single yarn fineness of 1.5 denier or less and filament B 2.0 denier or more after false twisting, and filament B is 80T/M. (twists/meter) with or without prior twisting, and align the filaments so that the mixing ratio of filament B is 30 to 80% by weight, and under the following conditions, make sure that there are no stuck or fused parts. A method for producing a processed yarn with a two-layer structure made of ultra-fine yarn, which is characterized by carrying out stretching and false twisting. [Math 1] 2. The method for producing a two-layer textured yarn of ultrafine yarn according to claim 1, characterized in that filaments A and B are twisted together at 80 T/M or less and then false twisted. 3. The method according to claim 1 or 2, wherein the filaments A and B after false twisting have a single yarn fineness of 1.0 denier or less and 3.0 denier or more, respectively. A method for manufacturing ultra-fine two-layer processed yarn. 4. The method for producing a two-layer textured yarn made of ultrafine yarn according to any one of claims 1 to 3, wherein the fiber is polyester.