JPH04245943A - Polyester fiber sliver, production of the same sliver and spun yarn using the same sliver - Google Patents

Abstract

PURPOSE:To provide a sliver eliminated in group cutting, concentration cutting, no-draft, etc., improved in productivity and stabilized in quality when tow consisting of a fiber having fine fineness is subjected to draft cutting. CONSTITUTION:A tow consisting of polyester fiber containing 3-15wt.% barium sulfate having <=0.4mum, primary particle diameter and <=3 denier fiber denier and 12-30% single fiber elongation is used and treated to provide the sliver.

Description

Description: [0001] The present invention relates to a method for directly producing a sliver from a tow made of polyester fibers by a tension cutting method, and to a spun yarn using the sliver. BACKGROUND OF THE INVENTION In recent years, research and development have been conducted on a method of forming a spun yarn using one or more false twisting nozzles using 100% polyester fiber. The spun yarn produced by this method is called bound spun yarn, and is being used for clothing, but it has a harder texture than real twisted yarn, and does not meet consumer needs. As it is, it is difficult to develop it into clothing. In addition, the tow-cut sliver method, which produces sliver all at once, was reviewed to save labor, simplify, and abbreviate the spinning process, and research and development of this method using polyester fiber, which is the most commonly used material for clothing, was conducted. is being carried out. [0003] However, polyester fibers generally have high strength and elongation and poor splitting properties, which causes concentrated cutting, mass cutting, or no draft during stretch cutting, resulting in poor stretch cutting properties and low productivity. This tendency is particularly noticeable in round cross-section fibers with a single fiber denier of 1 denier or less, or polyester fibers with irregular cross-sections such as T-shaped, polygonal, and multilobal shapes that cause surface contact between fibers. [0004] As a method to improve such problems,
Several methods have been proposed so far. For example, in Japanese Patent Publication No. 46-4090, the fiber group constituting the continuous fiber bundle is made to have no uneven thickness in terms of morphology and density,
Although a method for preventing concentrated cutting during tension cutting has been shown, it is not possible to completely eliminate concentrated cutting, much less to improve tension cutting performance such as collective cutting and no draft. [0005] Furthermore, Japanese Patent Publication No. 47-27806, Japanese Patent Publication No. 55-1378, and Japanese Patent Application Laid-open No. 53-49127 disclose that the cutting elongation of single fibers is changed so as to partially deviate greatly from the average value. It has been shown that concentrated cutting and group cutting can be prevented by making the fibers have a strength variation in the longitudinal direction of the fibers, or by varying the fineness and strength within a specified range. Because the physical properties of single fibers such as elongation, strength, and fineness differ due to tension cutting using these methods,
The cutting points will be widely dispersed throughout the tension cut area, and the frequency of concentrated cuts or group cuts will be much lower. In this respect, the fibers obtained by these methods are superior to commercially available polyester fiber tows. However, the sliver obtained by tension cutting these fiber bundle tows has an abnormally large fiber length distribution due to differences in the time required for tension cutting due to differences in the characteristics of individual single fibers, and the original elongation and
Since there are large variations in strength, fineness, etc., the single fibers that make up the sliver also have large variations in these properties. Therefore, the uniformity of the spun yarn obtained using this sliver is poor, and not only is it difficult to obtain a high-quality spun yarn, but there are various problems such as the occurrence of fluff and yarn breakage during spinning. It comes out. On the other hand, Japanese Patent Application Laid-Open No. 53-98414 discloses that the elongation at break of single fibers is reduced to about 25 to 40%, or that inert fine particles such as titanium dioxide, talc, or calcium carbide are added to the fibers. A method for cutting a tow of polyester fiber containing 0.1 to 1% by weight, and further disclosed in JP-A No. 5
3-31816 discloses a method for cutting the tow of polyester fiber containing 0.1 to 1% by weight of china clay or calcium carbonate fine particles inside the fiber, and JP-A-58-98420 discloses , the total average value of the breaking elongation of single fibers is 25% or less, the standard deviation value of the variation characteristics of the cutting elongation is 4.5% or less, and the single fiber denier is 0.3
~3 denier (examples are 1.2~1.5 dr, 2.9 d
r) A method of cutting off tow containing 0 to 1% by weight of inert fine particles such as titanium dioxide or calcium carbide, and furthermore, Japanese Patent Publication No. 56-34650 describes a method of cutting tow that corresponds to the above tow at 160°C or higher. JP-A-1-33216 discloses a method for producing a sliver, which is hot-stretched at a draft rate of elongation at break x (0.60 to 0.95) at a temperature below the generation temperature, and then tension cut. Methods for tension cutting polyester fiber tow containing ~10% by weight of silicon dioxide have been proposed, but these conventional techniques still result in concentrated cutting and collective cutting, and it is difficult to improve tension cutting properties. Not yet reached. In particular, with conventional techniques, tows made of fibers of 1.0 denier or less, and even 0.4 denier or less, have poor stretch cutting properties, and it is currently impossible to obtain a satisfactory sliver. SUMMARY OF THE INVENTION An object of the present invention is to provide a method for producing a sliver by cutting a continuous tow made of polyester fibers with a round or irregular cross section. Furthermore, when manufacturing sliver by cutting tow made of fibers with a fineness of 0.4 denier or less, group cutting, concentrated cutting, no-draft, etc. are eliminated, greatly improving productivity and improving quality. Another object of the present invention is to provide a stable sliver and a spun yarn using the sliver. [Means for Solving the Problems] That is, the present invention provides fibers with a primary particle size (center particle size) of 0.4 μm or less, a refractive index of 2.0 or less, and a true specific gravity of 2.9 or more. A sliver made of polyester fiber containing 3 to 15% by weight of fine particles, a single fiber denier of 3 denier or less, an average fiber length of 80 mm or more, and a single fiber elongation of 12 to 30%, or a tow made of polyester fiber in one or more stages. When producing a sliver by tension cutting in the tension cutting region of A method for producing a polyester fiber sliver characterized by using polyester fiber containing 3 to 15% by weight of fine particles, a single fiber denier of 3 denier or less, and a single fiber elongation of 12 to 30%, and a method for producing a polyester fiber sliver, and a method for producing a polyester fiber sliver, which is characterized by using a polyester fiber containing 3 to 15% by weight of fine particles, and a primary particle size in the fiber. Contains 3 to 15% by weight of fine particles with a (center particle size) of 0.4 μm or less, a refractive index of 2.0 or less, and a true specific gravity of 2.9 or more, a single fiber denier of 3 deniers or less, and an average fiber length of 80 to 110 mm. , is a spun yarn made of polyester fibers with a single fiber elongation of 12 to 30%, and in the present invention, in particular, a tow made of fibers with a fineness of 1 denier or less, further 0.4 denier or less, is used to make a sliver. It is characterized by its ability to achieve excellent tension cutting properties when manufacturing. [0009] In the present invention, the central particle size refers to the median diameter determined by centrifugal sedimentation. The polyester fiber used in the present invention has a primary particle size (center particle size) of 0.4 μm or less and a refractive index of 2.0.
Hereinafter, it is important to contain 3 to 15% by weight of fine particles having a true specific gravity of 2.9 or more, preferably 3.5 or more, more preferably 4.0 or more. [0011] Examples of such fine particles include barium sulfate, alumina, calcium carbonate, magnesium oxide, calcium phosphate, etc. Barium sulfate is particularly preferred since it can effectively achieve the object of the present invention. If particles with a refractive index exceeding 2.0 are used, the final dyed product will be whitish and only a pastel tone will be obtained, so it is preferable to avoid this. In addition, materials with low true specific gravity tend to have poor drape properties when knitted or woven. [0013] The fine particles may be mixed directly into the esterification tank or into a slurry, and preferably added after being dispersed in water, ethylene glycol, lower alcohol, or a mixture thereof. This seems to be because dispersing in a solvent with weak ionizability and strong polarity is effective in suppressing the association of fine particles. Addition after completion of polycondensation requires removal of the solvent and mixing, and in such a case it is not preferable because it tends to result in huge particles. In this case, the particle size of the added fine particles is 0.4
If it exceeds .mu.m, the system is likely to cause aggregation due to heat shock, etc., and once aggregation occurs, it is impossible to redisperse it. Therefore, in order to uniformly disperse the particles, it is desirable that the primary particle size (center particle size) of the fine particles be 0.4 μm or less, preferably 0.3 μm or less. The amount of fine particles added is preferably in the range of 3 to 15% by weight, preferably 5 to 10% by weight. If it is less than 3% by weight, concentrated cutting and collective cutting tend to occur in Parlock stretch cutting, making stable stretch cutting impossible, resulting in a decrease in productivity. On the other hand, if the content exceeds 15% by weight, spinning becomes extremely difficult and the fiber becomes brittle, which poses a problem. The polyester constituting the polyester fiber of the present invention may be a polymer of terephthalic acid or its ester-forming derivative, ethylene glycol, or 1,4-butanediol, that is, polyethylene terephthalate or polybutylene terephthalate, or a polymer mainly composed of them. Copolymers are preferably used. Copolymerized acid components include isophthalic acid, sulfoisophthalic acid, 5-sodium sulfoisophthalic acid, diphenyldicarboxylic acid,
Aromatic dicarboxylic acids such as naphthalene dicarboxylic acid, aliphatic dicarboxylic acids such as adipic acid, sebacic acid, and todecanedioic acid, and oxycarboxylic acids such as p-oxybenzoic acid and p-β-oxyethoxybenzoic acid are used as diol components. Examples include aliphatic diols such as 1,3-propanediol and 1,6-hexanediol, 1,4-bis(β-oxyethoxy)benzene, polyethylene glycol, and polybutylene glycol. [0017] The fine particle-containing polyester is 0.35 dl/
It is desirable to have an intrinsic viscosity of 1.5 g or more. If the intrinsic viscosity is less than 0.35 dl/g, the spinnability during spinning tends to deteriorate, which is not preferable. Here, the intrinsic viscosity is measured at 30° C. in a mixed solution of equal amounts of phenol/tetrachloroethane. It is necessary that the single fiber elongation of the polyester fiber used in the present invention is 12 to 30%, but fibers having such an elongation can be obtained by the commonly employed melt spinning method.
It can be obtained by appropriately selecting conditions such as the pore area of the spinneret, the single-hole discharge rate, the winding speed, the draw ratio, and the tension heat treatment in the winding-drawing heat treatment process. When the elongation exceeds 30%, the stretch cutting properties tend to deteriorate, and by setting the elongation within this range, it becomes possible to cut particularly high-strength, fine-denier tows. The fine particle-containing polyester fiber crimped tow thus obtained is subjected to Parlock tension cutting, and the thickness of the tow varies depending on the thickness of the sliver to be produced, but the total denier is in the range of 10,000 to 1 million deniers. It is appropriate that the The tension cutting may be performed in one stage or in multiple stages, and the tension cutting conditions may be the same as those generally employed, thereby producing a sliver with stable tension cutting properties and good quality. FIG. 1 shows an embodiment of the present invention. In the figure, the fine particle-containing polyester fiber tow (2) pulled out from the carton box (1) is placed in the tension guide (4) by the guides (3a) and (3b).
Guided by this process, tension is applied to remove the sag and tension in the fiber tow, and the tow is adjusted. In the tow that has entered the tension cutting area, the single fibers may partially sag, twitch, or sag, such as loops.
If tension occurs, it will cause concentrated cutting or collective cutting in the stretch cutting area, so it is desirable to remove the sagging and tension. [0021] As mentioned above, the total denier of tow can reach up to 1 million deniers, and in order to make tow with such a large denier, multiple tows stored in a carton box are collected in advance. In order to remove the sagging and tension of the collected tow, it is preferable to divide the tow into multiple stages and sufficiently adjust the tow. [0022] The adjusted tow subsequently enters a first tension cutting area consisting of a nip roller (5) and a tension cutting roller (6a). In this first stretch cutting area, the yarn length is usually 4.5
It is drafted and cut by at least 7 times, preferably 7 times or more. After undergoing the first stage tension cutting, in the figure, the subsequent tension cutting rollers (6b) and (6c) undergo second and third stage tension cutting to obtain a parlock sliver with a desired fiber length. Store it in the storage can (7). [0023] The manufacturing method of the present invention does not cause concentrated cutting, collective cutting, or no draft, and exhibits good tension cutting properties, which not only increases productivity but also provides uniformity in terms of fineness, strength, elongation, etc. A sliver is obtained. Therefore, a very homogeneous and flexible spun yarn can be obtained from the obtained sliver. Regarding the method for producing spun yarn, the above-mentioned sliver may be directly introduced into a spinning machine, or a continuous spinning machine,
It may also be used as a spun yarn through a roving frame or a spinning frame. 00
24 [Examples] The present invention will be specifically explained below with reference to Examples, but the present invention is not limited thereto in any way. In addition, in the physical properties of the obtained spun yarn, U%, IP
I is manufactured by Keizoku Kogyo Co., Ltd. (Model KET-80
B) U% Evenness tester was used. The smaller this value is, the better the uniformity is. Further, the number of fuzz was measured using an F-index tester manufactured by Toray model DT-104. Example 1 Intrinsic viscosity is 0.60 dl/g, central particle size is 0.30 μm
Polyethylene terephthalate to which 5% by weight of barium sulfate (refractive index 1.64, true specific gravity 4.49) was added was spun at a take-up speed of 1050 m/min using a triangular cross-section spinneret.
Wind it up and draw it 3.15 times by a conventional method, and the cross-sectional shape of the fiber is triangular as shown in Figure 2 (2-1), and the single fiber fineness is 0.
．． 4dr, strength 5.9g/d, elongation 19%, number of crimp 12
．． Fibers with a crimp rate of 7.0% and a crimp rate of 5 pieces/inch were obtained, and a tow with a toe denier of 690,000 dr was obtained. [0026] The tow is tensioned and aligned in the process shown in FIG. .72 times the draft, and a draft rate of 1.52 times in the second draft area, and a draft rate of 1 in the third draft area.
．． A parlock sliver was obtained at a rate of 94 times and a total draft rate of 22.7 times. The tension cutting property was very good. The characteristics of the obtained sliver were that the sliver U% was 2.8% as determined by Evenes tester, and the average fiber length was 105 mm. By using the sliver of the present invention, it is possible to
．． It was possible to obtain a spun yarn with a unique silk-like texture that is not found in spun yarns obtained from 3dr x 38 mm triangular cross-section staples. Example 2 Intrinsic viscosity is 0.62 dl/g, central particle size is 0.25 μm
Polyethylene terephthalate to which 10% by weight of barium sulfate (refractive index 1.64, true specific gravity 4.49) was added was spun and wound at a take-up speed of 1050 m/min using a T-type spinneret.
Stretched 3.1 times by conventional method, single fiber fineness 0.5 dr,
Strength 5.4g/dr, elongation 23%, number of crimps 11.8/
A T-shaped fiber with a crimp rate of 6.3% and a cross-sectional shape as shown in FIG. 2 (1-1) was obtained, and a tow with a tow denier of 480,000 denier was obtained. [0028] The tow thus obtained is tensioned in the process shown in FIG. The draft rate was 7.20x, and the draft rate was 1.45x in the second drafting area, the draft rate was 1.67x in the third drafting area, and the overall draft rate was 1.74x. The parlock slivers were obtained by cutting. The tension cutting property was very good. The characteristics of the obtained sliver were that the sliver U% was 3.1% and the average fiber length was 98 mm. Example 3 Intrinsic viscosity is 0.61 dl/g, central particle diameter is 0.27 μm
Polyethylene terephthalate to which 7 wt. Stretched 3.3 times, single fiber fineness 0
．． 4 dr, strength 5.4 g/dr, elongation 23%, crimp number 1
A fiber with a crimp rate of 6.3% and a crimp ratio of 2.1 strands/inch was obtained, and the toe denier was 630,000 dr. [0030] The tow thus obtained is tensioned in the process shown in FIG. Purlock slivers were obtained by cutting at a magnification of 4 to 10 times. The tension cutting property was very good. The obtained sliver had a sliver U% of 2% and an average fiber length of 82 mm. This sliver was directly spun using a spinning machine to obtain a 20'S spun yarn. Table 1 shows the physical properties of spun yarn.
It was shown to. Example 4 Intrinsic viscosity is 0.60 dl/g, central particle size is 0.27 μm
Polyethylene terephthalate to which 5% by weight of barium sulfate (refractive index 1.64, true specific gravity 4.49) was added was spun at a take-up speed of 1300 m/min using a round spinneret (round cross section), wound, and spun by a conventional method. Stretched 3.1 times, single fiber fineness 0
．． A tow with a tow denier of 510,000 dr. [0032] The tow thus obtained is tensioned and aligned in a process as shown in Fig. 1 to form a straight tow, and then guided to an area consisting of a nip roller and a tension cutting roller to achieve a total draft ratio of 4. Parlock slivers were obtained by cutting at ~8x. The tension cutting property was very good. The obtained sliver had a sliver U% of 2% and an average fiber length of 98 mm. This sliver was directly spun using a spinning machine to obtain a 20'S spun yarn. Table 1 shows the physical properties of the spun yarn. [Table 1] Comparative Example 1 The intrinsic viscosity (30°C, in ethanol-tetrachloroethane) was 0.60 dl/g, and barium sulfate was 1.0% by weight.
The polyethylene terephthalate contained therein was produced under the same spinning and stretching conditions as in Example 3 to obtain a polyester fiber crimped tow with a tow denier of 58 dr. Although the tow was stretched under the same conditions as in Example 3, concentrated cuts occurred frequently and the tension cutting performance was poor. [0035] According to the manufacturing method of the present invention, when a tow made of fibers with a fineness of 3 denier or less, particularly 1 denier or less, and even 0.4 denier or less is made into a sliver by the tension cutting method. In addition, there is no concentrated cutting, collective cutting, no draft, etc., and a sliver with good productivity and stable quality can be obtained, and the spun yarn obtained using the sliver has a refreshing and flexible texture. be.

[Brief explanation of the drawing]

FIG. 1 is an example of a process diagram for cutting tow used in the manufacturing method of the present invention.

FIG. 2 is a specific example of a cross-sectional view of polyester fibers used in the manufacturing method of the present invention.

[Explanation of symbols]

1 Carton box 2 Polyester fiber tow 3a, 3b Guide 4 Tension guide 5 Nip roller 6
a, 6b, 6c tension roller

Claims (6)

[Claims] [Claim 1] The fiber has a primary particle size (center particle size) of 0.
．． Contains 3 to 15% by weight of fine particles with a diameter of 4 μm or less, a refractive index of 2.0 or less, a true specific gravity of 2.9 or more, and a single fiber denier of 3.
A sliver made of polyester fibers having a denier or less, an average fiber length of 80 mm or more, and a single fiber elongation of 12 to 30%. [Claim 2]Claim 1 wherein the fine particles are barium sulfate.
The sliver described in. 3. When manufacturing a sliver by cutting a tow made of polyester fibers in one or multiple stages of tension cutting, the polyester fibers have a primary particle diameter (center particle diameter) of 0.4 μm or less in the fibers. Contains 3 to 15% by weight of fine particles with a refractive index of 2.0 or less, a true specific gravity of 2.9 or more, a single fiber denier of 3 denier or less, and a single fiber elongation of 12 to 30.
% of polyester fibers. [Claim 4]Claim 3 wherein the fine particles are barium sulfate.
The manufacturing method described in. [Claim 5] The fiber has a primary particle size (center particle size) of 0.
．． Contains 3 to 15% by weight of fine particles with a diameter of 4 μm or less, a refractive index of 2.0 or less, and a true specific gravity of 2.9 or more, a single fiber denier of 3 denier or less, an average fiber length of 80 to 110 mm, and a single fiber elongation of 12 to 110 mm. Spun yarn made of 30% polyester fiber. [Claim 6]Claim 5 wherein the fine particles are barium sulfate.
The spun yarn described in .