JPS6160182B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a woven or knitted fabric having excellent stretchability made of a multifilament bulky textured yarn having a single filament denier of 0.3 dr or more and less than 5 dr, consisting essentially of a polytetramethylene terephthalate polymer, and a method for producing the same. In recent years, there has been a strong demand for stretchable woven and knitted fabrics, which has expanded from active sports to casual wear and practical clothing. the current,
As materials for stretchable woven or knitted fabrics, polyurethane fibers (spandex) wrapped with other threads, nylon bulky yarns, and polyester, particularly polyethylene terephthalate bulky yarns, are used. Although woven and knitted fabrics using spandex have good elasticity, they are expensive and have poor chlorine resistance (a problem when used in a pool as a swimsuit). Woven and knitted fabrics made of yarn have poor elastic recovery when wet and poor dye fastness to chlorine, so it is necessary to select dyes with good fastness, resulting in only fabrics that tend to show steps or streaks. Furthermore, polyethylene terephthalate-based bulky yarns are expensive,
Although there are no problems with chlorine resistance and water resistance, the elastic properties are insufficient, and currently no woven or knitted fabric with high elasticity has been obtained. The present invention solves these drawbacks and provides excellent dyeing properties.
The present invention relates to a woven or knitted fabric made of a polytetramethylene terephthalate bulky yarn having preferably high elasticity. Although polytetramethylene terephthalate is widely known as a resin, there is relatively little research into its use as a fiber, especially in terms of stretchable woven and knitted fabrics, and only a few have been studied in JP-A-49-55919.
No. 49-55920 merely describes a method for producing bulky processed yarn. Even if the crimp rate (corresponding to the crimp elongation rate K ₁ in the present invention), which is the effect described in these publications, is very good,
45 to 56%, and it is not possible to obtain a good elastic woven or knitted fabric as described in the present invention from such fibers. That is, the present invention has an area elongation recovery rate R10 of ₈₀ in dry and wet conditions.
% or more and a single yarn denier of 0.3 _dr or more and less than 5 dr. Shrinkage fastness K ₃ /K ₁
It is necessary to use polytetramethylene-based bulky textured yarn with a polytetramethylene content of 80% or more. The present inventors have extensively studied the manufacturing conditions and processing conditions of polytetramethylene terephthalate fibers and the elasticity of the resulting woven and knitted materials.
The _K1 value obtained by spinning, drawing, and false twisting under specific conditions is 60% or more, and the _K3 / _K1 value is 80% or more.
By making a woven or knitted fabric from a multifilament having a drastic value of 0.3 dr or more and less than 5 dr, the woven or knitted fabric of the present invention with _R10 of 80% or more and good elasticity has been achieved. Crimp elongation rate K ₁ and crimp fastness K ₃ /
K ₁ is determined as follows. The crimped yarn was placed in a skein with a circumference of 1 m, made into a bundle of 5000 dr (2500 dr on each side), treated in hot water at 90°C for 30 minutes with a load of 5 g applied, and after air-drying without a load, a load of 5 g was applied for 5 minutes. Later, measure the length of the skein and call it l ₁ . Next, 500g
Apply a load of and measure l ₂ after 30 seconds. Next, 3.5Kg
Apply a load of 5g for 30 seconds, remove the weight, and then apply a load of 5g for 5 minutes.
l Measure ₄ . Crimp elongation rate K (%) = l ₂ - _{l 1} /l ₂ ×100 Crimp fastness K ₃ (%) = l ₂ - l ₄ /l ₂ ×100 Crimp fastness K ₃ /K ₁ = l ₂ −l ₄ /l ₂ −l ₁ The area elongation recovery rate R _x referred to in the present invention means the length 20
cm, width 5 cm fabric (warp direction is subscript a, weft direction is b), apply an initial load of 10 g and make length l ₀ . Next, apply a load of 1.5 kg for 1 hour and let the length at that time be l ₁ . Next, when the length when a load of 10 g is applied after weight removal is _l2 , it is expressed by the following formula. R _x (%)=l _2a ×l _2b -l _1a ×l _1b /l _2
a +l _2b -l _0a ×l _0b ×100 (x represents the recovery rate after x minutes after weight removal) Intrinsic viscosity when measured with an Utsperohde viscometer in a temperature bath. In addition, polymers consisting essentially of polytetramethylene terephthalate, in which 85 mol% or more is composed of tetramethylene terephthalate units, include terephthalic acid, isophthalic acid, adipic acid, sepacic acid, diethylene glycol, pentyl glycol,
Polyalkylene glycol, bisphenol A,
Copolymerized with sulfoisophthalic acid, etc., or additives of up to 10% by weight, such as matting agents, heat stabilizers, pigments, carbon, silica, or antistatic improvers.

【formula】

[Formula] The polyethylene glycol decyl benzene sulfonic acid having a group may also contain a compound containing P or Br as a flame retardant. In the method of the present invention, a substantially polytetramethylene terephthalate polymer in which 85 mol% or more of the repeating units are tetramethylene terephthalate units is heated to a temperature higher than (melting point + 30°C) of the polymer (melting point + 60°C). ℃) or less, the intrinsic viscosity [η] is 0.7 to 1.1 dl/g, and the birefringence is 80×
10 ^-3 or more and a density of 1.315 g/cc or less is stretched 1.2 to 5 times at a temperature of 100° C. or higher (melting point -10° C.) and then 150 to 210° C.
The single yarn denier after false twisting is 0.3 dr or more.
The present invention relates to a woven or knitted fabric with good elasticity using multifilament bulky yarn with a drastic length of less than 5 dr, and a method for producing the same. In the present invention, tetramethylene
If the terephthalate unit content is less than 85 mol%, the effects of the present invention cannot be exhibited. Usually, the melt spinning temperature is higher than the melting point of the polymer (melting point + 20
It is desirable to perform spinning in a temperature range below 30°F (°C), but polytetramethylene terephthalate polymers have an extremely fast crystallization rate, so the temperature of melt spinning is an important factor, and in order to achieve the effects of the present invention. needs to be spun at a temperature above (melting point +30°C) and below (melting point +60°C). In addition, in order to exhibit high-performance stretchability as in the present invention, the undrawn yarn must have an intrinsic viscosity [η] of 0.7 to 1.1 dl/g, which means that the length of the molecules is elastic. This is because it affects the character. Further, the birefringence index of the undrawn yarn must be 80×10 ^-3 or more; if it is less than that, spontaneous elongation will occur and the problem of bobbin slippage will occur. Further, the density must be 1.315 g/cc or less, and the features of the present invention cannot be exhibited with undrawn yarns having a density exceeding 1.315 g/cc obtained when spinning at a high speed of 6000 m/min or more. In addition, what is important in the present invention is that the stretching temperature is 100°C or higher.
(melting point -10℃) or less, and from the viewpoint of the performance of the target yarn and stable production, 1.2~
5 times is appropriate. Here, if the stretching temperature is less than 100°C, a good product with a K ₁ value exceeding 60% cannot be obtained. Also, the false twisting temperature is
150-210℃ is required, more preferably 170-200℃
It is ℃. In addition, the single yarn denier of undrawn yarn is 5 dr.
The above materials have a poor elongation recovery rate, and the woven or knitted fabric of the present invention cannot be obtained. The woven or knitted fabric of the present invention is suitable for swimwear, leotards, golf pants, ski pants, etc., and exhibits unprecedented elasticity and durability. The features of the present invention will be shown below in Examples, but the scope of the present invention is not limited thereby. Example 1 Chips made of polytetramethylene terephthalate (melting point 221°C) were melt-spun at 270°C and at a speed of 1200 m/min to give a birefringence index (hereinafter referred to as Δn) of 120×.
10 ^-3 , density (hereinafter referred to as ρ) 1.302 g/cc, [η]
An undrawn yarn of 165 dr/24 fil with =0.92 was obtained. Then, the yarn was heated to a roller temperature of 78℃ and a plate temperature of 78℃.
It was stretched 2.2 times at 140°C to 75 dr/24 fil. Next, the false twisting temperature was 190℃ and the number of false twists was 3380T/m.
We carried out bulk processing. The _K1 value of such processed yarn is
It showed a high crimp length ratio of 73%, which has never been achieved before, and the K ₃ value was 63%, so K ₃ /K ₁ = 86
% and crimp fastness were also good. Next, when a 32 gauge smooth knit was knitted using this bulky processed yarn, the area elongation recovery rate _R10 was 94 in dry condition.
%, and 87% in wet condition. Examples 2 to 5 and Comparative Examples 1 to 9 Polytetramethylene terephthalate chips (melting point 221°C) with [η] = 1.17 and 0.83 were spun and stretched to 50 dr/24 fil under various conditions, and then false twisted. The crimpability was evaluated. The results are shown in Table 1.

[Table] 〓〓〓〓

[Table] As is clear from this table, in Comparative Example 1 where the spinning temperature was 240°C, Δn was relatively small, even with high-temperature false twisting.
The _K1 value was 53%, which was comparable to that of ordinary false twisted yarn. In Comparative Example 2, the K ₁ was only 4% because the stretching temperature was low. On the other hand, in Example 2 where the drawing temperature was 120° C., the K ₁ value was 70% and the K ₃ /K ₁ value was 88%, resulting in an unprecedented high bulk fiber. In Comparative Example 3, a good K ₁ value could not be obtained due to low [η], and in Comparative Example 4, the K ₁ value was 60% due to the same reason as Comparative Example 2.
It couldn't have gone any further. Example 3 of the present invention is K ₁
Although the K ₃ /K ₁ value of Comparative Examples 5 and 6 is 71% and 87%, the K ₁ value of Comparative Examples 5 and 6 is low due to the low false-twisting temperature.
No samples with K ₃ /K ₁ values of 60% or more and 80% or more were obtained. Example 4 has a _K1 value of 77
% and K ₃ /K ₁ value of 90%, which shows an amazing crimp performance. In Comparative Example 7, spontaneous elongation occurred due to the small Δn, and the film could not be taken up stably and could not be passed through the post-stretching process. In Comparative Example 8, the K ₁ value was 55% because the specific gravity of the undrawn yarn was as large as 1.316 g/cc, but the K ₃ /K ₁ value was only 73%. Example 5 also showed unprecedented high crimp performance. In Comparative Example 9, despite using a chip with [η] = 1.17, it decreased to 0.63,
Satisfactory results were not obtained in terms of productivity and crimpability. Examples 6 to 8 and Comparative Examples 10 to 13 Bulky processed yarns obtained in Examples 2, 4, and 5 (referred to as G-2, G-4, and G-5, respectively) and Comparative Examples 2, 6, and 8 The obtained bulky processed yarn (respectively S-
2, S-6, and S-8) to make 32 gauge smooth knits and evaluate them. The results are shown in Table 2.

[Table] Comparative Example 13 is an example of a commonly used bulky processed nylon yarn. Comparative Examples 10 to 12 showed almost the same performance as nylon in terms of dry area elongation recovery rate.
Wet ones are better than nylon. On the other hand, in the embodiment of the present invention, it is more than 90% dry,
It can be seen that even in wet conditions, it shows extremely excellent elastic recovery performance of 83-88%. 〓〓〓〓

Claims (1)

[Scope of Claims] 1. A polytetramethylene terephthalate polymer in which 85 mol% or more of the repeating units are composed of tetramethylene terephthalate units, and a crimp extension ratio K ₁ of 60% or more; Crimp fastness K ₃ /
A stretchable woven or knitted fabric using a multifilament bulky textured yarn with a K ₁ of 80% or more (K ₃ is crimp fastness) and a single yarn denier of 0.3 dr or more and less than 5 dr as the main weaving or knitting yarn. 2 Melt-spinning a substantially polytetramethylene terephthalate polymer in which 85% or more of the repeating units are composed of tetramethylene terephthalate units at a temperature of (melting point + 30°C) or more and (melting point + 60°C) or less of the polymer. The intrinsic viscosity [η] is 0.7 to 1.1
dl/g, birefringence Δn is 80×10 ^-3 or more, density ρ is
Undrawn yarn with a weight of 1.315 g/cc or less is heated at 100°C or higher,
(melting point -10℃) or less after stretching 1.2 to 5 times and then 150
Crimp elongation rate K ₁ 60 obtained by false twisting at ~210℃
% or more, crimp fastness K ₃ / K ₁ 80% or more, single yarn denier 0.3 dr or more but less than 5 dr, multifilament bulky textured yarn is used as the main yarn to produce a stretchable woven or knitted product. Method.