JPH08100342A - Spun polyester sewing yarn - Google Patents

Abstract

PURPOSE: To obtain the subject sewing yarn having a combination of good sewability compatible with high-speed sewing process and stitch appearance with no inferiority. CONSTITUTION: Two fleeced fiber bundles in parallel with each other produced via a draft zone are simultaneously twisted in the same direction at a twist multiplier of 3.5-5.0 into a fine-spun single yarn. Plural number of the yarn are then arranged in parallel with one another and bundled and then subjected to ply twisting at a twist multiplief of 4.0-5.3 in the direction opposite to that of the single yarn, and the resultant strand is put to finishing treatment such as dyeing and oiling, thus obtaining the objective sewing yarn which has at 300-600 per 10m of >=1mm fluff index and <=30 per 10m of >=3mm fluff index.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sewing thread made of polyester staple fiber which is excellent in sewability and has very little occurrence of fly cotton during sewing.

[0002]

2. Description of the Related Art Japanese Patent Application No. 2-11 previously proposed by the present applicant
4132 (JP-A-4-11038),
Polyester sewing thread has characteristics such as high tenacity, uniformity of quality, and excellent dyeing fastness. As the products to be sewn have recently been made into polyester, the market share of cotton sewing thread has been increasing instead of cotton sewing thread. is there. The polyester sewing thread is roughly classified into a polyester filament sewing thread made of polyester filament and a polyester spun sewing thread made of polyester short fiber, depending on the form of the raw thread.

The former polyester filament sewing thread is superior to the latter polyester spun sewing thread in terms of the beauty of the seam due to its high uniformity, but when it is used in a sewing machine that rotates at a high speed, the sewing needle has a high temperature. Therefore, there is a problem that the polyester filament yarn is melted and the sewability is deteriorated.

On the other hand, the polyester spun sewing thread has a large surface area because it has fluffs, and since it has a heat dissipation effect due to the fluff, it has excellent heat resistance, but its strength is slightly inferior to the polyester filament sewing thread. Further, there are disadvantages such as Young's modulus, generation of cotton wool, and poor passability of the sewing machine needle due to fluff, and there is a problem that sewing with a sewing machine that rotates at a high speed deteriorates the sewability of the arrow.

[0005]

As a method for solving the above-mentioned problems existing in the conventional polyester filament sewing thread and polyester spun sewing thread, Japanese Patent Laid-Open No. Sho 6-62 has been proposed.
1-97438 discloses a twisting coefficient of undertwisting of 2.00 to 3.10 in a sewing thread made of polyester short fibers.
Discloses an invention in which the twist coefficient of the upper twist is set to 5.40 to 6.80, and the occurrence of fluff is suppressed by giving such a high twist twist to the sewing thread, and JP-A-2-33341, JP-B-6-51935 and the like propose sewing threads in which spun yarn made of polyester short fibers and polyester filament yarns are mixed and twisted so as to complement each other's disadvantages. ing.

However, the former method, that is, setting the twisting coefficient of the upper twist to a high value of 5.40 to 6.80 leads to a decrease in productivity in the twisting process, and gives a high twist to the yarn. In addition, a heat setting step is required to prevent snare in the subsequent step, and as a result, there is a fatal disadvantage that the sewing thread manufacturing cost increases. Also, in the latter method of mixing and twisting short fiber yarns and polyester filament yarns, since the physical property values such as elongation and shrinkage ratio differ between both yarns, short fiber yarns and polyester filament yarns are mixed and twisted. At that time, a special tension control device is required in the twisting process,
It requires extensive remodeling of conventional equipment and complicates production management. There is a problem that a good sewing thread cannot be obtained unless these points are complemented. The present invention is intended to solve the above problems in the conventional polyester spun sewing thread, and provides a new polyester spun sewing thread having good sewability compatible with high-speed sewing and a comparable stitch appearance. It is the one we are trying to provide.

[0007]

In order to achieve the above object, the present invention has the following constitution. That is, it is a sewing thread composed of polyester short fibers, and as a raw thread, two parallel fleece-like fiber bundles obtained via a draft zone are simultaneously and simultaneously provided with a twist coefficient of 3.5 to 5.0. Using a spun single yarn twisted in the same direction, a plurality of original yarns are aligned and combined, and then 4.0 to 4.0 in the direction opposite to the single yarn twisting direction.
In the product state, which is twisted with a twist coefficient of 5.3 and subjected to finishing treatment such as dyeing and oiling, the fluff index of 1 mm or more is 300 to 600 per 10 m, and 3 mm
The gist is that the above-mentioned fluff index is 30 or less per 10 m. In the present invention, the twist coefficient is a value represented by twist coefficient = T / √N (where T is the number of twists per inch (2.54 cm) and N is an English cotton count).

In the above-mentioned constitution, as the polyester constituting the polyester short fiber of the present invention, JP-A-59-
High strength, low elongation and low heat shrinkability as described in Japanese Patent No. 125905 are suitable, and polyethylene terephthalate is the main object, but within a range that does not essentially change its properties (for example, 15 It may be a copolymer of the third component (mol% or less). Examples of such a third component include isophthalic acid, 5-sodium-sulfoisophthalic acid, paraoxybenzoic acid, ciethylene glycol, 1.4-butanediol and the like. The intrinsic viscosity (η) of polyester is preferably 0.60 or more. If it is less than 0.60, it is difficult to obtain a high-strength fiber. These polyesters may contain a small amount of additives such as matting agents, colorants, stabilizers, flame retardants and moisture absorbents.

The polyester short fibers of the present invention are obtained by spinning polyethylene terephthalate as described above by a conventional method to obtain an undrawn yarn tow of about 1.5 million tenier, and then the above-mentioned JP-A-59-125905 or JP-A-59-125905. Sho 59-15
It is a stable fiber having high strength, low elongation, and low heat shrinkability, which is obtained by passing through the drawing process described in JP-A No. 0109 and then cutting it into a predetermined length with a cutter. It is suitable that the single yarn denier of the polyester short fibers is in the range of 0.5 to 1.5 and the fiber length is in the range of 38 to 44 mm.

Next, the raw thread used for the sewing thread of the present invention will be described. The raw yarn is a single spun yarn obtained by twisting two parallel fleece-like fiber bundles obtained through a draft zone of a spinning machine at the same time and in the same direction with a predetermined twist coefficient, that is, a so-called so-called single yarn. It is necessary to be a single spinning yarn obtained by “silospan spinning”. The roving is formed by forming the polyester short-fiber cotton described above into a fiber bundle having a predetermined weight by passing through the respective steps of a blended cotton-cardboard-kneading-rough spinning which is a normal spinning step. The roving is formed into the raw thread for the sewing thread of the present invention by the spinning process described below.

FIG. 1 is a perspective view showing an outline of a spinning machine for producing the raw yarn. In the figure, (1) and (2) are supplied roving yarns manufactured by the above process, and (3) is a roving yarn guide. The two supplied roving yarns (1) and (2) supplied in parallel in the aligned state enter the respective roving yarn running grooves (3A) and (3B) of the roving yarn guide (3), and then a pair of upper and lower bags. A pair of rollers (4), a pair of upper and lower middle rollers (6) having an apron (5), a pair of upper and lower front rollers (7), a back side of the pair of front rollers (7), and a front bottom roller (7A). The collector (8) located above (only its mounting position is shown in FIG. 1), is subjected to a predetermined drafting action by the above draft mechanism (9),
Two fleece-like fiber bundles (10) and (11) that are parallel to each other are formed, and immediately after they leave the nip point of the front roller pair (7), they are twisted by a ring traveler mechanism (not shown) to form a single yarn twist. Twin yarn twist is continuously applied and wound on a bobbin (not shown) in the form of a single spinning yarn.

A spinning method using the apparatus shown in FIG. 1 is what is called a so-called silospan spinning by those skilled in the art.
A characteristic of this spinning process is that the fleece-shaped fiber bundles (10) and (11) immediately after exiting the front roller pair (7) are separated into two threads at a predetermined distance. Unlike the conventional spinning method that gives a real twist, it is a highly efficient production device that can obtain a promptly twisted yarn with a spinning machine, and the obtained yarn quality is almost the same as the twisted twine yarn obtained by the conventional method. A major feature is that it can be manufactured evenly and at dramatically low cost.

The twist coefficient applied to the above-mentioned spun single yarn is 3.
A range of 5 to 5.0 is suitable. If the twisting coefficient is less than 3.5, the occurrence of cotton wool due to slipping due to the fluff of the polyester short fibers is large, and if it exceeds 5.0, the binding force of the fibers is large, and the fluff has a shocking force. When added, the fluff is cut and the fluff is reduced, so that the heat resistance is inferior, which is not preferable.

A plurality of, usually two, spun single yarns of the raw yarn for sewing machine yarns formed as described above are aligned and combined, and then this is twisted by an ordinary twisting machine, preferably a double twister, and further. Preferably, it is twisted in a direction opposite to the twisting direction of the original yarn with a twist coefficient of 4.0 to 5.3 by a double cheese machine of the sun cheese type. If the twisting direction in the twisting process is the same as the twisting (lower twisting) direction of the original yarn, the force to return to the opposite direction of the twisting direction when the upper twist is applied, and the twisting state occurs.
As a result, the sewability deteriorates. Therefore, it is necessary that the upper twist direction is opposite to the lower twist direction. The twist coefficient of the upper twist is as described above, but if it is less than 4.0, the occurrence of fluff is increased due to slipping due to friction of the polyester short fiber fluff, and if it exceeds 5.3. Causes an increase in twisting torque, which causes the yarn to be twisted and deteriorates the sewability. Therefore, the above range is required.

Further, the sewing machine thread after the twisting machine is required to have a fluff index within the specific range described above in a product state after finishing treatment such as dyeing and oiling.
That is, the fluff index of 1 mm or more is 300 to 600 per 10 m.
That is, the fluff index of 3 mm or more is 30 or less per 10 m. The fluff index specified in the present invention is JIS
It is based on the general spun yarn test method specified in L1095, and is a testing machine F-IN manufactured by Shikishima Spinning Co., Ltd.
Measured for 5 samples using DEXTESTER and converted per 10m. Sample speed is 3
0m / min, test length is 20m, predetermined fluff length is 1mm and 3
It is set to 2 mm.

The fluff of the sewing thread is generally evaluated by the number of fluffs per unit length and the length of the fluffs. Originally, the fluff has a heat dissipation effect, prevents the temperature of the sewing thread from rising, and improves the sewability, but if fluff is excessively present, the friction resistance increases and the passing property of the sewing needle deteriorates. However, it may reduce the sewability and cause seams and puckering. The fluff of the sewing thread has the effect of improving the sewability by having an appropriate number of fluffs per unit length.If the ratio of long fluffs increases, the fluff will separate during sewing and the fluff will stick to the sewing needle. Otherwise, fluff may be accumulated under the needle plate or inside the bobbin bobbin box, which may reduce the sewing effect.

Concretely explaining by taking the above matters into consideration,
In the sewing thread according to the present invention, when the fluff index of 1 mm or more is less than 300 per 10 m, the degree of tightness is deteriorated and the heat resistance is deteriorated in high-speed sewing. On the other hand, the fluff index of 1 mm or more is 6 per 10 m
When it exceeds 00, the appearance of the seam deteriorates and the above-mentioned defect due to excessive fluff occurs. Further, when the fluff index of 3 mm or more exceeds 30 per 10 m, the defect due to the above-mentioned long fluff appears. Therefore, the fluff index in the above range is required in the sewing thread of the present invention.

[0018]

According to the polyester spun sewing machine yarn of the present invention having the above-mentioned constitution, since the spun single yarn as the original yarn is obtained by silospan spinning, the performance and the low cost of the spun yarn even though it is a single yarn. Is equipped with. Further, the polyester spun sewing thread of the present invention has a fluff index in a specific range in a finished product state after finishing treatment such as dyeing and oiling. , It has both heat dissipation during sewing and sewability that can support high-speed sewing.

[0019]

The present invention will be described in more detail with reference to the following examples. Polyethylene terephthalate having an intrinsic viscosity of 0.65 was spun by a conventional method at a take-up speed of 1000 m / min to obtain an undrawn yarn tow of about 2.5 million denier. Next, the unstretched tow was passed through the process described in JP-A-59-125905 to obtain polyester short fiber cotton. The short fiber cotton has a fineness of 1.0 d, a fiber length of 42 mm, and a dry strength of 7.8 g /
d, cutting elongation 17.0%, dry heat shrinkage (170 ° C x 15
Min) rate was 1.2%. The above-mentioned short fiber cotton was passed through a normal spinning process to form a roving yarn, and two roving yarns were set in a ring spinning machine shown in FIG. 1 to manufacture a silospan-spun single spinning yarn.

In the manufacturing process of the above-mentioned spun single yarn (sewing yarn raw yarn), various spinning conditions were studied for the purpose of imparting appropriate fluff to the raw yarn, and as a result, the fleece-like fiber bundle (10) ( It turned out that the interval of 11) is extremely important. Table 1 shows the test results.

[0021]

[Table 1]

Basically, if the interval between the two fiber bundles is too wide, the spinnability is reduced and a uniform raw yarn cannot be obtained. Conversely, if it is too narrow, the fluff index of the fine spinning single yarn obtained increases. There is a tendency. The spinning count of the single spinning yarn shown in Table 1 is 56 (English cotton count, the same applies hereinafter) and the twist direction is S twist. Therefore, it is judged that the spacing naturally changes depending on the spinning count, in other words, the roving count, but in the example of the fine spinning single yarn No. 56, it is determined that the fiber bundle spacing is preferably 5 mm.

The example No. 1 shown in Table 1 above was used. The number of spinning single yarn of No. 2 (5 mm roving interval) and the number of spinning single yarn of No. 42 produced in the same manner are double twister No. 363 made by Murakami Machinery Co., Ltd. Twisting was performed to obtain two unprocessed sewing thread. Further, these unprocessed sewing threads are dyed with a cheese dyeing machine using a disperse dye at 130 ° C. for 30 minutes, and then 3% by weight of silicone oil is attached to the processed sewing threads, that is, finishing such as dyeing and oiling. A processed final product was obtained.

The above product according to the present invention and a commercially available product
In order to compare the twisted sewing thread, the polyester short-fiber cotton described above is used to make 84th yarn by the ordinary spinning process.
And unwound sewing thread 84/3 count, 64 with a twisting coefficient of 4.5, upper twisting direction Z, and lower twisting direction S using the above-mentioned twisting machine. / 3rd sewing thread was manufactured. Similar to the example according to the present invention, the 84/3 count and 64/3 count raw sewing threads were dyed with a disperse dye at 130 ° C. for 30 minutes using a cheese dyeing machine, and then 3% by weight of silicone oil was used. A sewing thread that had been attached and processed was obtained.

[0025] 56/2 ^S, 84/3 ^S comparative example of the embodiment of the final product obtained by the process of Example 42 /
2 ^S, Table 2 shows the results of testing the physical data 64/3 ^S of Comparative Examples each opponent's the fluff tester or the like.

[0026]

[Table 2]

Tests A and B in which the total counts are almost equal
In each of the above categories, the material of this example is comparable to the comparative example in basic physical property values such as yarn strength and cutting elongation, and is substantially equivalent, but in terms of the fluff index. It was clear that the improvement was drastic.

Furthermore, polyester spun sewing thread 60 / which is a general commercially available thread of each company purchased between April and June 1994.
3 ^S (5 cases) and sewing thread 42 ^{S of the} embodiment according to the present invention
Table 3 shows a comparative test with 2.

[0029]

[Table 3]

As can be seen from Table 3, the sewing thread of the example according to the present invention has a fluff index of 1 mm or more, which is 1 of the commercially available threads.
It was about / 3 and proved to be extremely excellent.

A first sewing test was carried out using the sewing threads of the example and the comparative example adopted in test B of Table 2. The test conditions are shown below, and the test results are shown in Table 4. Seams: Men's shirt H Bar tack sewing Machine used: JUKI LK-984-193 Fabric used: Polyester / cotton (50% / 50%) 50 ^S broad

[0032]

[Table 4]

Similarly, a second sewing test was carried out using the sewing threads of the example and the comparative example adopted in the test A of Table 2. The test conditions are shown below, and the test results are shown in Table 5. Seams: Neck stitching with symmetrical adhesive interlining Machine used: JUKI-AVP-800 Fabric used: 100% cotton, 100/2 ^S broad

[0034]

[Table 5]

As shown in Tables 4 and 5, the polyester spun sewing machines according to the examples of the present invention exhibit good results in terms of fluff accumulation during sewing, sewing mistakes, and the number of thread breaks.

Further, a third sewing test (seam puckering test) was conducted on the sewing thread of the example adopted in the test A of Table 2. As a comparative example, a twisted yarn (commercially available product) of polyester spun yarn and polyester filament was used. The test conditions are shown below, and the test results are shown in Table 6. Sewing machine used: JUKI DDF-5570 (lock stitch) Material used: 100% cotton, 100/2 ^S broad bobbin thread tension: 10 g ・ Hand movement: 18 needles / 3c
m Press: temperature 170 ° C., time 20 seconds, pressure 50
0g / cm ² Washing: Home washing machine Liquid temperature 60 ℃, Time 5 minutes ×
6 times, synthetic detergent drying: Line drying

[0037]

[Table 6]

[0038]

EFFECT OF THE INVENTION According to the polyester spun sewing thread of the present invention, as shown in the above-mentioned examples, although the basic physical properties such as thread strength and cutting elongation are almost the same as those of the conventional similar sewing thread, In addition, the manufacturing cost can be greatly reduced, and since it has an appropriate amount of fluff, it has excellent sewability and a seam appearance.

[Brief description of drawings]

FIG. 1 is a perspective view showing a main part of a spinning machine for producing a raw thread for a sewing thread according to the present invention.

[Explanation of symbols]

 1, 2 supply roving thread 3 roving thread guide 3A, 3B roving thread running groove 7 front roller pair 8 collector 9 draft mechanism 10, 11 fleece fiber bundle

Claims (1)

[Claims] 1. A sewing thread made of polyester short fibers, which comprises, as a raw thread, two parallel fleece-shaped fiber bundles obtained through a draft zone with a twist coefficient of 3.5 to 5.0. Using a spinning single yarn that is twisted in the same direction at the same time, a plurality of original yarns are aligned and combined, and then twisted in a direction opposite to the single yarn twisting direction of 4.0 to 5.3. When the product is twisted with a coefficient and subjected to finishing treatment such as dyeing and oiling, the fluff index of 1 mm or more is 3 per 10 m.
A polyester spun sewing thread having a fluff index of 0 to 600 and a fluff index of 3 mm or more is 30 or less per 10 m.