JP2002285428A - Stretchable mixed yarn with yarns having different finenesses - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stretchable mixed yarn with yarns having different finenesses, equipped with an elegant dignity, a highly stretchable property, tenacity, a body, a resilient feeling, a puffy feeling and a soft feeling without having crimps and wrinkles. SOLUTION: This stretchable mixed yarn with yarns having different finenesses consists of at least >=3 kinds of filament yarns, in which whole single yarns constituting the mixed yarn of which at least its high viscosity component is a polytrimethylene terephthalate, are side by side type conjugated yarns; the mixed yarn consists of (A) thin fineness yarns of 0.5-3.0 dtex single yarn fineness, (B) middle fineness yarns of 0.7-5.0 dtex single yarn fineness and (C) thick fineness yarns of 3.0-15.0 dtex single yarn fineness; the number of filaments (Fa) of the thin fineness yarns is 29 fold of that of the thick fineness yarns (Fc) and >=2 fold of that of the middle fineness yarns (Fb); and also the 1.8×10<-3> cN/dtex elongation rate stretched and contracted under a load of the mixed yarn is >=20%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mixed-filament yarn comprising at least three or more filament yarn groups, and more particularly, to a single-filament yarn having a different viscosity. The present invention relates to a high-stretch mixed yarn having at least a high-viscosity component of polytrimethylene terephthalate in which at least 80% by mole of a repeating unit is trimethylene terephthalate. The present invention relates to a mixed-strength yarn of different stretchability which exhibits excellent surface quality and stretch, waist, resilience and softness.

[0002]

2. Description of the Related Art Conventionally, polyesters have various excellent properties including mechanical properties, and thus have been widely used not only for clothing. In addition, various methods have been adopted for imparting stretchability, crimpability, and bulkiness to polyester yarn by a recent stretch boom.

[0003] For example, there is a method in which a polyester yarn is subjected to false twisting to exert a twisting / untwisting torque to impart stretchability. However, there is a problem that when this torque is used for a woven fabric, the surface of the woven fabric is textured, which is likely to be a defect of the woven fabric. On the other hand, various techniques have been proposed for obtaining a crimped yarn by compound spinning polymers having different shrinkage characteristics or melt viscosities into a side-by-side type or an eccentric core-sheath type. For example,
JP-B-44-2504 and JP-A-4-308271.
JP-A-5-295634 discloses a side-by-side composite yarn of polyethylene terephthalate (hereinafter abbreviated as PET) having an intrinsic viscosity difference or an intrinsic viscosity difference, and JP-A-5-295634 discloses a side-by-side of a homo PET and a copolymer PET having a higher shrinkage. Molded composite yarns are described. If such a crimped polyester composite yarn is used, it is possible to obtain a certain degree of stretchability, but the stretchability when used in a woven fabric is insufficient, and it is difficult to obtain a satisfactory stretchable woven fabric. was there. This is because the side-by-side type composite yarn as described above has a low crimp development performance while the fabric is constrained, and is easily crimped.

Japanese Patent Application Laid-Open No. Hei 11-189923 proposes a polyester-based composite yarn comprising PET and polytrimethylene terephthalate (hereinafter abbreviated as PTT) having a lower melt viscosity. However, if PTT is PE
When the viscosity is lower than T, for most of the developed crimping forms, the inside of the crimped coil becomes a PET component, and the outside becomes a PTT component. A well-known technique for obtaining a crimped yarn by side-by-side composite using PET having different intrinsic viscosities and intrinsic viscosities, and the stretchability and the retention of crimp development are also extremely low. There is a problem that it is not changed at all.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned drawbacks and problems of the prior art, to have high stretchability, and to provide a texture when used in a woven or knitted fabric.
It is an object of the present invention to provide a stretchable mixed-fiber mixed yarn from which a product having an excellent surface quality without wrinkles, tension and waist, a swelling feeling, a resilience feeling, and a soft feeling can be obtained.

[0006]

In order to achieve the above object, the present invention provides a mixed yarn of different fineness comprising at least three or more filament yarn groups, wherein all the single yarns constituting the mixed yarn have a viscosity Is a side-by-side type composite yarn composed of two different polyesters, wherein at least the high-viscosity component is polytrimethylene terephthalate in which at least 80 mol% of the repeating units are trimethylene terephthalate, and the mixed fiber group has a single-filament fineness. 0.5-3.0 dtex fineness yarn group (A) and single yarn fineness 0.7-5.0 dte
x medium-fine yarn group (B), a large fine yarn group (C) of 3.0 to 15.0 dtex, and the number of filaments (Fa) of the fine fine yarn group is a filament of the large fine yarn group Number (F
c) 9 times or more, the number of filaments (F
b) or more, and 1.8 × 10 ^{−3 of the} mixed fiber.
It can be achieved by a stretchable mixed fineness mixed fiber, wherein the stretch ratio under cN / dtex load is 20% or more.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
In the present invention, among the two-component polymer constituting all the single yarns of the mixed fiber, at least the high-viscosity component needs to be polytrimethylene terephthalate in which at least 80 mol% of the repeating units are composed of trimethylene terephthalate. It is. In the PTT, the methylene chain of the alkylene glycol moiety in the crystal structure has a Gauche-Gauche structure (the molecular chain is bent at 90 degrees), and the density of constraint points due to the interaction (stacking, parallel) between benzene rings is low. Because of its high flexibility, it has a characteristic stretch property that the molecular chain is easily extended and recovered by the rotation of the methylene group. This is because the stretch property inherent in PTT is sufficiently exhibited even in the composite yarn.
In the present invention, the composite ratio of the two components in all the single yarns constituting the mixed fiber is not particularly limited as long as it is a composite ratio generally used for imparting elasticity by a side-by-side composite. 65: 35-35: 65
And preferably from 60:40 to 40:60.

In the present invention, in all the single yarns constituting the mixed fiber, the low-viscosity component of the two-component polymer may be polyethylene terephthalate or polybutylene terephthalate. Trimethylene terephthalate may be used.

[0009] The mixed fiber yarn of the present invention is composed of at least three or more filament yarn groups of a fine fine yarn group (A), a medium fine yarn group (B) and a large fine yarn group (C). You. The single-fiber fineness of this fine-fiber yarn group (A) is 0.5 to 3.0 dtex.
It is necessary to be.

The fine fiber group (A) has high crimpability, is arranged on the surface of a woven or knitted fabric, forms a texture and appearance, and imparts high stretchability and softness. The single yarn fineness of the fine fiber yarn group (A) is 3.
0 dtex or less, preferably 2.5 dtex or less. On the other hand, if the single-filament fineness is too small, the crimp becomes too fine and the stretchability of the woven or knitted fabric cannot be obtained, so that it is 0.5 dtex or more, preferably 1.0 dtex or more.

The single yarn fineness of the medium fineness yarn group (B) needs to be 0.7 to 5.0 dtex. When the group of fine fine yarns (A), the group of medium fine yarns (B), and the group of thick fine yarns (C) are mixed, the medium fine yarn group (B)
Also mainly forms the surface of the woven or knitted fabric, but is mixed with the fineness yarn group (A) to give sufficient stretchability and natural unevenness, and to prevent the surface from exhibiting grain and wrinkles. The single yarn fineness of the fineness yarn group (B) is 0.7 dtex or more, and preferably 1.5 to 4.0 dtex.
5.0 dtex or less is required to exhibit natural unevenness and softness as a three-component blend.

Further, it is necessary that the single yarn fineness of the thick fine yarn group (C) is 3.0 to 15.0 dtex. The single yarn fineness is 3.0 dtex or more, preferably 5.0, in order to impart sufficient tension, waist, and resilience when woven or knitted.
dtex or more. If the single-fiber fineness is too large, not only does the woven or knitted fabric have a rough and hard texture, but also the crimping property becomes too small to obtain a stretch property, and the high stretch property as a mixed fiber is maintained. 15.0 dtex or less, preferably 12 dtex
It is as follows.

As described above, the high stretch property and the tension and waist,
In order to achieve both a swelling feeling, a resilience feeling and a soft feeling, and to impart a natural unevenness feeling, it is necessary that each yarn group of fine fineness, medium fineness and large fineness has the fineness as described above.

Next, the number of filaments (F
In a), the number of filaments (Fc) of the large fine yarn group is 9 times or more, and the number of filaments of the medium fine yarn group (Fb) is 2 times or more. In a woven or knitted fabric composed of stretchable composite yarns having different crimping properties, the woven or knitted fabric surface is formed, and the softness is lowered not only when the number of filaments in the fineness yarn group mainly exhibiting high stretch performance is small. , Sufficient stretchability cannot be obtained. Further, the different crimping properties between the yarn groups are too conspicuous, so that a natural uneven feeling cannot be obtained, and the surface when used in a woven or knitted fabric is wrinkled or wrinkled. Therefore, in order to improve the stretchability, softness and quality of the woven or knitted fabric, (Fa) is at least 10 times, preferably 15 times or more of (Fc), and simultaneously (Fa) is at least 2 times of (Fb).
Preferably it is three times or more.

[0015] In the present invention, 1.8 combined filament yarn × 10 ^-3
The expansion and contraction rate under cN / dtex load needs to be 20% or more. The measuring method will be described later. 1.8 × 10 ^-3 cN
When the elongation at stretch under the / dtex load is less than 20%, the stretchability when used in a woven or knitted fabric is poor, and the stretchable woven or knitted fabric is not suitable. 1.8 × 10 ^-3 cN / dte
The stretch ratio under x load is preferably 30% or more.

In the present invention, in all the side-by-side composite yarns of the fine fine yarn group and / or the medium fine yarn group and / or the large fine yarn group constituting the mixed fiber,
The two intersections of the straight line X passing through the center of the line segment OP connecting the two contact points O and P between the joining surface of the two components of the single yarn cross section and the yarn outer periphery and being orthogonal to the line segment OP and the composite yarn outer periphery Q and R,
Assuming that two intersections between the straight line Y passing through the center of the line segment QR and orthogonal to the line segment QR and the outer periphery of the yarn are S and T, the length ratio QR / ST of the line segment QR and the line segment ST is 1. It is preferably in the range of 2 to 4.0. The effect of securing the thickness of both polyester components and easily obtaining sufficient stretch performance with respect to the joining surface of the two components of the composite yarn cross section, making it easy to obtain a swelling feeling and resilience when mixed with three fibers. The effect of the present invention is to provide an effect, to suppress the bending and swirling of the discharged yarn during melt spinning, to obtain uniformity in the yarn longitudinal direction and stable yarn production, and to provide a ratio of the length of the line segment QR to the line segment ST. QR / ST is more preferably in the range of 1.5 to 2.0.

The production method of the side-by-side composite spinning in the present invention is not particularly limited, and an ordinary composite spinning machine may be used. May be adopted, without once winding the unspun yarn that has been composite spun,
A direct spin drawing method of heating and drawing may be employed.

In the present invention, there is no particular limitation on the production method of the mixed fiber, and a method in which each yarn group having a different fineness is individually manufactured and then mixed and processed may be used. A direct spinning and mixing method in which each yarn group is spun and drawn from a single die may be used, but it is preferable to use a direct spinning and mixing method in terms of manufacturing cost.

[0019]

The present invention will be described in more detail with reference to the following examples.

Intrinsic viscosity in the text and examples, 1.8 ×
10 ^-3 cN / dtex stretch under load, texture (stretch, stretch / hip, swelling, rebound, softness),
The surface quality (texture / wrinkle, irritability) and overall evaluation are as follows.

A. Intrinsic viscosity: 0.1 mL of the sample polymer in 10 ml of orthochlorophenol (hereinafter abbreviated as OCP).
8 g was melted and the relative viscosity ηr was calculated at 25 ° C. using an Ostwald viscometer by the following equation (IV). ηr = η / η ₀ = (t × q) / (t ₀ × q ₀ ) IV = 0.0242ηr + 0.2634 where η: viscosity of polymer solution, η ₀ : viscosity of OCP,
t: Fall time (second) of the solution, q: density of the solution (g / cm)
³⁾ t _0: OCP drop time (in seconds), q _0: Density of OCP (g / cm ^3).

B. 1.8 × 10 ⁻³ cN / dtex Stretching and elongation ratio: A case with 10 turns wound by a hand-held measuring instrument with a circumference of 1 m, and a load of 1.8 × 10 ⁻³ cN / dtex is applied. Is treated with hot water at 90 ° C. for 20 minutes. After measuring the air-dried original length L1, disconnect the load of 1.8 × 10 ^-3 cN / dtex, to measure the length L2 after two minutes under a load of 88.3 × 10 ^-3 cN / dtex , The value (%) obtained from the following equation. Stretch elongation rate = {(L2-L1) / L1} × 100 Texture (stretchability, tension and waist, swelling feeling, rebound feeling, softness) Using a PET drawn yarn of 56 dtex 18 filaments for the warp, weaving in a plain weave structure using the composite yarn obtained for the weft, And 95 ° C x 40
For 20 minutes, sensory evaluation was performed on the fabric obtained by hot water treatment for 10 minutes and air-dried by pairwise comparison with a reference fabric. The reference fabric is made of PE of 84 decitex and 48 filaments for the weft.
Weaved and processed in the same manner as described above using a T-drawn yarn. The reference fabric was evaluated by the number of persons judged to be excellent, and ○ and Δ were set as acceptance criteria. 18 or more: ○, 14-17: Δ, 13 or less: × Surface quality (texture / wrinkle): Evaluated as follows by the number of texturing / wrinkles in a 50 cm wide × 200 cm long fabric which was subjected to the same weaving, scouring, hot water treatment, and air drying as the fabric used for evaluating the texture. , △ and △ were taken as acceptance criteria. 0 to 1: O, 2 to 4: Δ, 5 or more: X Surface quality (irritability): Sensory evaluation was performed by 20 panelists on the fabric used for evaluation of stretchability. The surface of the fabric was observed under a commercially available 40-watt fluorescent lamp, and evaluated by the number of people who judged that there was no irritability on the surface. 18 or more: ○, 14-17: Δ, 13 or less: × Comprehensive evaluation: In consideration of the above-mentioned respective evaluation items, comprehensive evaluation was performed as follows, and ○ and Δ were regarded as acceptance criteria. △ 3 judgments or less: ○, 4 judgments or more: Δ, × with judgment items: × Example 1: Intrinsic viscosity 1.
47 with PTT of 47 as a high viscosity component
With ET as a low viscosity component, the yarn cross section is a perfect circle and PT
The volume ratio of T to PET is 1: 1 and the single yarn fineness is 0.5d
A heterofilament mixed fiber composite comprising a yarn group A having tex and 36 filaments, a yarn group B having a single yarn fineness of 0.7 dtex and 8 filaments, and a yarn group C having a single yarn fineness of 3.0 dtex and 4 filaments The yarn was melt spun. The stretchability of the obtained yarn is 28%, and the stretchability of the product using this yarn is at a level that does not cause any problem as a stretch fabric, and it has good texture with tightness, waist, swelling feeling, resilience, and softness. Obtained. In addition, the surface quality of the product was excellent without any wrinkles, wrinkles or irritations.

Example 2: Single yarn fineness of 3.0 dtex, yarn group A having 45 filaments, and single yarn fineness of 5.0 dtex
-Yarn group B with 2 filaments, single yarn fineness 15.0 dt
ex. Except for being composed of a yarn group C having 1 filament,
In the same manner as in Example 1, mixed fineness composite yarn was obtained. The stretch ratio of the obtained yarn is 42%, and the product using the yarn has good stretchability and resilience.
A product having no problem in swelling and softness and no problem in product surface quality was obtained.

Example 3: Single yarn fineness of 1.0 dtex, yarn group A having 36 filaments, and single yarn fineness of 2.0 dtex
-Yarn group B having 9 filaments, single yarn fineness 5.0 dte
Except that the yarn group C was composed of x and the number of filaments was 3, the same composite yarn with different fineness was obtained in the same manner as in Example 1. The stretch rate of the obtained yarn is 66%, and the product using it has extremely high stretchability and softness.
There was no problem in waist, swelling, and softness, and the product surface quality was excellent with no grain, wrinkle or irritability.

Example 4: The discharge hole of the yarn group A at the time of melt-spinning is formed in a slit type discharge hole shape, and the yarn cross section is QR /
Except that the slit hole shape (slit width / slit length) was adjusted so that ST = 1.5, a mixed-fiber composite yarn was obtained in the same manner as in Example 3. The stretch rate of the obtained yarn is 56%, and the product using it has very high stretchability, tightness, waistiness and softness, and has no problem in swelling and softness. Grade is grain
An excellent product without wrinkles and irritations was obtained.

Example 5: The yarn cross section of all yarn groups is QR
Except for adjusting the shape of the slit hole (slit width / slit length) so that /ST=1.5, a mixed fineness composite yarn was obtained in the same manner as in Example 4. The stretch ratio of the obtained yarn is 62%, and the product using the yarn has very high stretchability, tightness, waist, swelling and softness, and the surface quality of the product is smooth, wrinkled and irritable. A very good thing without it was obtained.

Example 6: Yarn group A was converted to single yarn fineness of 2.0 dt
ex • filament number 38 • QR / ST = 1.5, yarn group B was changed to single yarn fineness 6.0dtex • filament number 8 •
QR / ST = 1.2, yarn group C is single yarn fineness 10.0 dt
Example 1 except that the shape of the slit hole (slit width / slit length) of the discharge hole of each yarn group was adjusted so that ex / number of filaments 2 / QR / ST = 2.0.
In the same manner as described above, a mixed fineness composite yarn was obtained. The stretch ratio of the obtained yarn is 46%, and the product using this yarn has high stretchability, tightness, waist, swelling feeling and softness, and the surface quality of the product is excellent without any wrinkles, wrinkles or irritations. Was obtained.

Example 7: Intrinsic viscosity of 0.65 for low viscosity component
The yarn group A is QR / ST = 1.5, the yarn group B is QR / ST = 1.2, and the yarn group C is QR / ST =
Except that the slit hole shape of each yarn group was adjusted to be 2.0, a mixed fineness composite yarn was obtained in the same manner as in Example 6. The stretch rate of the obtained yarn is 43%, and the product using this yarn has high stretchability,
An excellent product having a swelling feeling and excellent softness and having no graininess, wrinkles, or irritations in the product surface quality was obtained.

Example 8: Intrinsic viscosity of 0.60 for low viscosity component
Of polybutylene terephthalate (hereinafter abbreviated as PBT), the yarn group A has a QR / ST = 1.5, and the yarn group B
Is QR / ST = 1.2, yarn group C is QR / ST = 2.0
Except for adjusting the shape of the slit hole of each yarn group so as to obtain a mixed fineness composite yarn in the same manner as in Example 6. The stretch rate of the obtained yarn is 55%, and a product using the same has high stretchability and excellent tension and waist.
It has a swelling feeling and softness, and the product surface quality is
An excellent product without wrinkles and irritations was obtained.

Example 9: All yarn groups are QR / ST =
Except that the slit hole shape of each yarn group was adjusted to be 4.0, a composite yarn with a different fineness was obtained in the same manner as in Example 6. The stretch ratio of the obtained yarn was 26%, and the product using this yarn had no problem in stretchability, and obtained a material having excellent tension and waist, swelling feeling, and softness. In addition, a product having no problem in surface quality was obtained.

Comparative Example 1: Single yarn fineness of yarn group A is 0.2 d
A mixed fiber with different fineness was obtained in the same manner as in Example 5, except that the tex was changed to tex. The stretch and elongation percentage of the obtained yarn was as low as 11%, and the product using this yarn could not be said to be a stretch woven fabric.

Comparative Example 2: Single yarn fineness of yarn group B is 6.0 d
A mixed fiber with different fineness was obtained in the same manner as in Example 5, except that the tex was changed to tex. The stretch ratio of the obtained yarn was 27%, and although a product using the yarn had no problem as a stretch fabric, it had a rough and hard feeling and had no softness.
In addition, the surface of the product became noticeably grainy and irritable, and the surface quality of the product was inferior.

Comparative Example 3: Single yarn fineness of yarn group C was 20.0
A mixed fiber with different fineness was obtained in the same manner as in Example 5, except that dtex was used. The stretch rate of the obtained yarn is 14%.
Thus, the product using this was not a stretch woven fabric, and had a rough and hard feeling and lacked softness. In addition, although there was no irritability on the product surface, grain and wrinkles became conspicuous, and the surface quality was poor as a product.

Comparative Example 4: Single yarn fineness of yarn group A is 4.0 d
A mixed fiber with different fineness was obtained in the same manner as in Example 5, except that the tex was changed to tex. The stretch ratio of the obtained yarn was 9%, and the product using this yarn could not be said to be a stretch fabric, and the swelling feeling and the softness were insufficient.

Comparative Example 5: A mixed fiber with different fineness was obtained in the same manner as in Example 6, except that the number of filaments in the yarn group A was changed to 5. The stretch rate of the obtained yarn was 13%, and the product using this yarn could not be said to be a stretch fabric, and also lacked tension, waist, swelling, resilience and softness. Became noticeable in the texture of wrinkles and wrinkles.

Comparative Example 6: Intrinsic viscosity of 0.76 for high viscosity component
The yarn group A is QR / ST = 1.5, the yarn group B is QR / ST = 1.2, and the yarn group C is QR / ST =
Except that the slit hole shape of each yarn group was adjusted to be 2.0, a mixed fineness composite yarn was obtained in the same manner as in Example 6. The stretch ratio of the obtained yarn was 15%, and the product using the yarn had a satisfactory level of tension, waist, swelling and rebound, but lacked softness.
Also, the stretchability was low and it could not be said to be a stretch fabric.

[0037]

[Table 1]

[0038]

[Table 2]

[0039]

As described above, according to the present invention, PTT is used as the high-viscosity component of the side-by-side type composite yarn, and the composite yarn is formed of three or more filament yarn groups. As fine fine yarn group, medium fine yarn group,
Single yarn fineness of a large fineness yarn group, and the number of filaments of each yarn group shall appropriate, 1.8 × 10 ^-3 cN / dtex
By making the expansion and contraction rate under load appropriate, it is elegant and free of wrinkles and wrinkles, high stretchability, tension and waist,
It is possible to obtain a mixed yarn having a different stretchability and a different degree of fineness, which has both resilience, swelling and softness.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a yarn showing an embodiment of the present invention.

[Explanation of symbols]

O: The contact point between the two-component joining surface of the yarn cross section and the yarn outer periphery P: The other contact point between the two-component joining surface of the yarn cross section and the yarn outer periphery X: The line segment AB passes through the center of the line segment AB Q: Intersection between the straight line X and the outer periphery of the yarn R: Intersection between the straight line X and the outer periphery of the yarn Y: A straight line passing through the center of the line segment CD and orthogonal to the line segment CD S: Between the straight line Y and the outer periphery of the yarn Intersection T: Intersection between the straight line Y and the outer periphery of the yarn

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Claims (2)

[Claims] 1. A mixed yarn of different fineness comprising at least three or more filament yarn groups, wherein all single yarns constituting the mixed yarn are side-by-side type composite yarns comprising two-component polyesters having different viscosities. At least 80 mol% of the high-viscosity component of the repeating unit is polytrimethylene terephthalate in which trimethylene terephthalate is composed of trimethylene terephthalate, and the mixed fiber yarn group has a single-filament fineness of 0.5 to 3.0 dtex. ) And single yarn fineness is 0.7 to 5.0 dte
x medium-fine yarn group (B), a large fine yarn group (C) of 3.0 to 15.0 dtex, and the number of filaments (Fa) of the fine fine yarn group is a filament of the large fine yarn group Number (F
c) 9 times or more, the number of filaments (F
b) or more, and 1.8 × 10 ^{−3 of the} mixed fiber.
A stretchable mixed fineness mixed fiber, wherein the stretch ratio under cN / dtex load is 20% or more. 2. The side-by-side composite yarn of each of the fine and fine yarn groups and / or the thick and fine yarn groups constituting each of the mixed fiber yarn groups. A straight line X passing through the center of a line segment OP connecting the two contact points O and P between the joining surface of the two components and the outer periphery of the yarn and orthogonal to the line segment OP
When two intersections of the straight line Y passing through the center of the line segment QR and orthogonal to the line segment QR and two intersections of the yarn outer periphery with S and T, respectively, the line segment QR and The stretchable heterogeneous mixed-yarn according to claim 1, wherein a ratio QR / ST of the length of the line segment ST is 1.2 to 4.0.