JPH0357209B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a manufacturing method for obtaining a bulky spun yarn, and more particularly, to a manufacturing method for a bulky spun yarn that potentially has both a wool-like feel and a silky appearance. In recent years, spun yarns made of fibers blended with polyester fibers have been widely used due to their excellent properties, and spun yarns made of polyester, wool, blends, and polyester-cotton blends are representative examples. Spun yarns made only of polyester fibers are also beginning to be used. However, these spun yarns have poor bulkiness, and their uses are limited to some extent. In order to impart bulkiness, staple fibers of two or more types of polyester fibers with different shrinkage rates are mixed in a cotton blend or carding process, or after the sliver is produced, a method is used in which they are mixed in a drawing machine, gill, etc. It is being However, increasing the types of fibers with different shrinkage rates is difficult in terms of manufacturing process and cost.
It is extremely difficult and practically impossible. On the other hand, the bulkiness of the product becomes better as more types of fibers with different shrinkage rates are blended. Further, at that time, if fibers having different lengths are blended, even better bulkiness can be obtained. The present invention aims to provide a method for producing an ideal bulky spun yarn that achieves these requirements for bulkiness at low cost and through a simple manufacturing process, and has a silky appearance. This is the purpose. In order to achieve this object, the present invention has the following configuration. That is, in the present invention, when passing a polyester continuous fiber bundle through one or more stretch-cutting regions and cutting the stretch-cutting region, at least in one stretch-cutting region,
A bulky spun yarn characterized in that the fiber bundle is tension-cut while being heated to a temperature equal to or higher than the glass transition point of the fibers to form a staple fiber group, and then subjected to a focusing treatment to form a spun yarn. This is the manufacturing method. In the present invention, the polyester fiber used may be any polyester containing 80 mol% or more of ethylene terephthalate units. However, when making a knitted fabric from a spun yarn made only of polyester fibers to exhibit bulkiness, pill generation becomes a problem, so anti-pilling polyester is used, and blends with short fibers such as cotton are recommended. In such cases, it is preferable to use polyester that can be easily dyed and can be dyed levelly at normal pressure and boiling temperature in order not to lose the feel of the natural fiber during dyeing. An example of this polyester fiber is a copolyester containing 80 mol% or more of ethylene terephthalate units, in which 0.5 to 5.0 mol% of the acid component is a 5-metal sulfoisophthalic acid component, and the glycol component is HO-(CiH ₂ iO -)m R-O-(
Examples include fibers containing glycol represented by _CjH2jO- )nH in an amount of 0 to 10% by weight based on the copolyester. When these polyester fibers are cut by a tension cutting device comprising two or more pairs of rollers, a heating element is installed in the tension cutting area, and the continuous polyester fiber bundle is heated and cut by tension. It is more preferable that the heating body is installed in the first tension cutting area. The reason is the first
After the continuous fibers have been tension-cut in the tension-cutting region, the tension-cutting point extends over the entire tension-cutting region due to the action of relaxation heat treatment in the tension-cutting region, that is, the tension-cutting of each fiber is This is because by varying the length and time of the subsequent relaxation heat treatment, it is possible to impart different shrinkage rates to each fiber. In addition to this effect, the fiber length distribution due to tension cutting is constant in the fiber bundle length direction, and only certain fibers
Since it does not have a long fiber length, very random different fiber length effects and different shrinkage effects are imparted. For the purpose of increasing this effect, it is also possible to install a heating body in the tension cutting area after the second tension cutting area. In short, if a heating element is installed in at least one of the one or more tension cutting regions and tension cutting is performed while heating the polyester continuous fiber bundle to a temperature equal to or higher than the glass transition point of the polyester fiber, the present invention can be achieved. The goal will be achieved. Any heating element can be used, such as a non-contact type double-sided heater or a contact type single-sided heater, but it is necessary to have the ability to effectively heat the fiber bundle evenly. The temperature at which the fiber bundle is heated by the heating element is preferably higher than the glass transition point and lower than (melting point -10)C from the viewpoint of the shrinkage treatment effect. When the temperature exceeds (melting point -10)℃, it begins to fuse,
If it is below the glass transition point, the heating effect will be insufficient and it will be difficult to produce a difference in shrinkage rate. The fiber bundle uses a so-called tow (continuous fiber bundle) with very high fiber parallelism as a starting yarn, and is made into staple fiber by directly cutting the tow, so it is different from the conventional card→
Blended batted cotton has much better uniformity than staple fiber bundles that have gone through the carding process. Naturally, the spun yarn produced from the staple fiber bundle has good fiber parallelism. Furthermore, since the relationship between single fiber fineness and fiber length is not limited, it is also possible to produce spun yarn made of staple fibers with fine fineness and long fiber length. This is a major factor in giving the spun yarn of the present invention a silky appearance. Another great effect of the present invention is that when tension cutting is carried out through one or more tension cutting regions, a heating element is installed in at least one of the tension cutting regions, and the continuous fiber bundle is tension cut while being heated. , the average shrinkage level of the cut fiber bundle is reduced. We have described the effect of the synergistic effect of different shrinkage blends and different fiber length blends on spun yarns made of staple fiber bundles, but the shrinkage rate level of fibers with low shrinkage rates also increases.
This is a major factor that determines the texture of the bulky spun yarn. The reason for this is as follows. This is because if the shrinkage level of the low shrinkage fiber is high, when blended with natural fibers, the polyester fibers will enter the yarn inner layer too much, resulting in an excessively bulky state, that is, bulkiness. The staple fiber bundle thus obtained may be bundled by any method such as a real twist method using a ring traveler, an open end method, or a bundling method. As a process for developing bulkiness, if the steps of staple fiber bundle production and bundling treatment are discontinuous,
This can be done either before the binding process, after producing the spun yarn, or after producing the knitted fabric. In the case of continuous production, it may be carried out either after producing a spun yarn or after producing a knitted fabric. An example of the method for producing the bulky spun yarn of the present invention will be explained with reference to the drawings. The tow 2 stored in the tow can 1 is transferred to the creel 12,
It is supplied to the supply roller 3 via the guide 13, is applied with tension in the stretching region A between the supply roller 3 and the roller 4, is supplied to the next first stretch cutting region B, and is cut in tension. A heating element 8 heats the tow in this first tension cutting region B, and the fiber ends after tension cutting are subjected to a relaxing heat treatment. The tension-cut fiber bundle subjected to the relaxation heat treatment passes through the roller 5 and is supplied to the second tension-cutting area C consisting of the rollers 5 and 6, where it undergoes corrected tension-cutting, passes through the delivery roller 7, and is delivered to the klumper 9. The sliver is then crimped and stored in a can 10 as a sliver 11. As described above, according to the present invention, a bulky spun yarn can be easily produced due to the synergistic effect of different fiber lengths and different shrinkage rates, and knitted fabrics using this bulky spun yarn can be dyed and finished, and then processed into wool. It has a similar texture and a silky appearance. Of course, during production of the spun yarn, it is also possible to combine it with a filament yarn to obtain a composite spun yarn. Examples 1 to 2 Using the tension cutting device shown in FIG. 1, a non-contact type heater was installed as a heating element 8 between the rollers 4 and 5 (first tension cutting area B) to cut the tow from above and below. It was set up so that it would heat up. The tow used is made of polyester fiber of 150,000 denier (single fiber fineness 1.0 denier). Further, the heating time of the tow by the non-contact type heater is 1.8 seconds. Other conditions and physical properties of the obtained staple fibers are shown in Table 1.

[Table] The SHD (dry heat shrinkage rate) indicated in *1 in the table is based on JISL1073, and the sample length L (=25 mm) is determined by applying a load of 50 mg/d to the staple fiber, and then hanging it in a dryer at 160°C. Leave it for 30 minutes, then add the original 50mg/d.
L ¹ (mm) was determined by applying a load of , and the average value of 10 values determined by the formula L-L ¹ /L×100 was shown. Also *2
SHD CV (%) is the SHD value 100 CV
(%). The thus obtained slivers (average fiber length 83 mm) were each made into roving yarns using a Super Rover, and then spun yarns of Nm48 ¹ S (meter count) were produced using a ring spinning machine. Using this spun yarn,
A double knit (interlock) was knitted, then dyed, and its physical properties were measured and are shown in Table 2.

[Table] In the table, the basis weight (g/m ² ) is based on JISL1004, and three samples (20cm x 20cm) are taken, and the weight (g) of each sample with the moisture level is measured.
The average value was expressed as weight (g) per 1 m ² . In addition, the thickness (mm) is also based on JISL1004, and the thickness (mm) is measured when a pressure of 240 g/cm ² is applied for 10 seconds using a thickness measuring machine at 5 or more locations on a sample (20 cm x 20 cm). It was expressed as the average value. Furthermore, the compression ratio was also measured in accordance with JISL1004-1972 and is shown in the same table. From the table, the knitted fabrics of Examples 1 and 2 are thicker and therefore bulkier than those of Comparative Examples 1 and 2, and the compression ratio is also twice as large as that of Comparative Examples 1 and 2. It had a wool-like soft texture. Furthermore, the knitted fabrics of Examples 1 and 2 were elegant and had a silky appearance.

[Brief explanation of drawings]

The figure is a side view of the tension cutting device used in the present invention. 1... Tow can, 2... Tow, 8... Heating body, 9
...Crimper, 10...Cans, 11...Sliver, A...Stretching area, B...First tension cutting area, C...
Second tension cutting area.

Claims (1)

[Claims] 1. When passing a polyester continuous fiber bundle through one or more tension cutting regions and tension cutting, the fiber bundle is tension cut while being heated to a temperature equal to or higher than the glass transition point of the fiber in at least one tension cutting region. A method for producing a bulky spun yarn, which comprises forming staple fibers into a group of staple fibers, and then subjecting the fibers to a convergence treatment to form a spun yarn.