JPH0433893B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing synthetic fibers for blow molding having down-like feel, drape properties, heat retention properties, and bulk properties. Bird feathers have traditionally been used for various fillings. However, natural feathers have problems such as quantitative limitations, complexity in manufacturing, uneven quality, and high price, making it difficult to use them for a wide range of purposes. There has been an increasing demand for filling materials with the following characteristics. The feathers used for various fillings consist of small feathers obtained from the wing parts of waterfowl and down obtained from the breasts. Products with a higher proportion of down are softer and have better drape, and are bulkier and more expensive. It is treated as. The present invention relates to a method for producing synthetic fibers for blow molding that have downlike flexibility, bulk, and heat retention properties, and are made by blowing the synthetic fibers directly onto the side fabric using an air flow using a blow molding machine used for feathers. The purpose of the present invention is to provide a method for easily producing synthetic fibers. A method for producing feather-like synthetic fibers for blow molding using synthetic fibers has already been proposed. For example, as shown in Japanese Patent Publication Nos. 52-28425 and 57-50308, the method of modifying ordinary fibers by attaching silicone oil to them can certainly improve drapability slightly, but the bulk is insufficient. The texture is completely different from that of feathers, and only those with poor compression recovery properties can be obtained. Furthermore, as shown in Japanese Patent Publication Nos. 48-7955 and 57-29134, the method of making the fiber aggregate state spherical or radial is certainly unique in terms of morphology, but it does not satisfy the characteristics of feathers. It has not become familiar. In addition, as shown in Japanese Patent Application Laid-Open No. 56-141206, staple fibers that are fine denier and have a low coefficient of friction can be used as synthetic fibers to provide a soft texture, excellent heat retention, and excellent drapability. is known to be obtained. Synthetic fibers with a fine denier of 3 deniers or less and a low coefficient of friction provide a downlike feel, heat retention, and drapability. Fragility deteriorates. That is, the synthetic fiber itself has many scallop-shaped unopened fiber portions, resulting in a low bulk. Therefore, if you try to directly blow fine denier synthetic fibers into the side fabric using a blow-molding machine (stuffing machine) for natural feathers, the synthetic fibers may wrap around the blower fan or clog the blower or duct. Packing work cannot proceed smoothly. Even if you manage to proceed with the stuffing process, the synthetic fibers in the side fabric are not sufficiently opened and have a low bulk, and they also form lump-shaped fiber clumps, resulting in unevenness on the surface of the stuffing. This is undesirable because it impairs the quality of the product and the texture when worn, giving a sense of discomfort. Strictly considering the spreadability, there are two definitions. 1. Uniform opening property: There are parts in the fiber aggregate where single fibers form a cluster to form a scallop shape, and parts where single fibers are separated from each other, and when the latter ratio is high, uniform opening is performed. It is said to have good sex. 2. Bulky fiber-spreading properties: Uniform fiber-spreading properties in fiber aggregates are poor, that is, there are relatively many scallop-like collective fibers, but when the scallop-shaped collective fibers and a large number of separated single fibers are randomly dispersed and become bulky, bulky fibers become bulky. It is said to have good opening properties. In addition, if the uniform spreadability is good, the bulky fiber spreadability also tends to be good. In the present invention, the fiber spreading rate is defined by the following equation as a measure of uniform fiber spreading property. Opening rate (%) = total fiber amount (g) - scallop-like collective fiber amount (g) / total fiber amount (g) x 100 As a measure of bulky fiber opening ability, as described in detail below in the present invention, unpacking Adopts rear no-load bulk. From the results of the studies conducted by the present inventors, it has been found that the workability of the blow molding machine is good and the bulkiness of the obtained filling is good when both the uniform spreadability and the bulky spreadability are high. In conventional synthetic fiber production methods, the spun raw yarn is generally combined into a tow of 100,000 to 3,000,000 denier, which is then stretched at an appropriate stretching ratio, and then crimped by applying an oil agent. The crimps are then heat-set and immediately cut into staple fibers, which are packed in bales. It has been found that with such conventional methods for producing synthetic fibers, there is a limit to the ability to obtain synthetic fibers with a single filament fineness of 3 deniers or less that have a high opening rate and are bulky. For example, no matter how much the compressed air pressure is increased in an attempt to open the staple fiber by blowing compressed air strongly with an air nozzle after cutting the tow, the effect is almost ineffective. In addition, even after being made into staple fibers and transported through air ducts until the packaging process, almost no separation occurs.
Not opened. Furthermore, it was found that when increasing the amount of an oil agent that gives flexibility to the tow in order to obtain a softer, down-like texture, the adhesive force of the agent itself causes the single yarns to stick to each other, impairing opening properties. In addition, increasing the crimp performance to an extreme degree in order to improve the bulkiness of the filler also worsens the opening performance. As mentioned above, in conventional synthetic fiber manufacturing methods, when synthetic fibers with a single filament fineness of 3 denier or less and treated with a treatment agent are used, it is difficult to blow with a normal feather blow-molding machine, or even if blowing is possible. Only low bulk fillings were obtained. The purpose of the present invention is to improve the above-mentioned drawbacks, and to provide a synthetic fiber that has excellent blow moldability, is extremely bulky and flexible, has excellent heat retention properties, and has good drapability even when the single fiber fineness is 3 deniers or less and is treated with a softener. An object of the present invention is to provide a method for producing synthetic fibers for blow molding with good properties. In other words, the present invention is directed to ``having one or more protrusions that are continuous in the fiber axis direction, and having a single yarn fineness of 3 denier or less,
Heat-set crimped tow with interfiber friction coefficient of 0.3 or less,
It is characterized by passing through a process of repeating relaxation and tension in at least the length direction of the tow to produce tension fluctuations, then cutting it into fiber lengths of 200 mm or less, and then immediately blowing compressed air to separate and open the fibers. ``Method for producing synthetic fibers for blow molding''. The synthetic fibers used in the present invention may be polyester-based, acrylic-based, polyamide-based, polyolefin-based, etc., but polyester-based synthetic fibers are most preferred from the standpoint of bulkiness. The single yarn fineness is 3 denier or less to approximate the soft texture, drapability, and heat retention of downlike.
Particularly preferred is 1 denier or less. In order to increase the bulkiness and heat retention of the stuffing, we use different denier fibers that are almost uniformly mixed in a ratio of 0.001 to 0.5 denier and 0.5 to 3 denier in a ratio of 20:80 to 80:20, respectively. It is a preferred embodiment to use a mixture. From the point of view of spreadability, the cross-sectional shape of the fibers is one that has one or more protrusions on the side surface of the fibers, so that it is easy to cause misalignment between the fibers when the tow is opened, for example, any cross-sectional shape such as those shown in Figs. 3 to 22 is used. Those with a cross-sectional shape are preferable, and those with a high degree of irregularity are more preferable. Moreover, in order to improve both heat retention and bulkiness, hollow fibers having a non-circular cross-sectional outer periphery with a hollowness ratio of 3 to 45% are more preferable. For example, Figures 4 to 8, 10
22, etc. When the above-mentioned hollow fibers are used, the cross-sectional shape of the fibers is greatly deformed by external force when the tow is opened, making it easier to open the tow. The coefficient of static friction between fibers (hereinafter referred to as μs)
The measurement method is based on JIS L-1074,
The smaller the value, the better the smoothness between the fibers.
In the present invention, when μs is 0.30 or less, the opening property during tow opening is good, and the resulting fiber has a down-like and extremely soft texture. μs
If it exceeds 0.30, the opening properties during tow opening will deteriorate, and at the same time, the texture of the resulting fibers will also be poor, which is undesirable. In order to make μs 0.30 or less, it is preferable to treat with a surface treatment agent mainly composed of silicone resin. Specific examples of silicone resins whose main component is silicone resin include methylhydrodiene polysiloxane, which reacts and cures on the fiber surface to form a film, epoxy group-containing polysiloxane, amino group-containing polysiloxane, and oxyalkylene group-containing polysiloxane. , methylvinylpolysiloxane, alkoxypolysiloxane, and mixtures thereof, and reactive organopolysiloxanes in which these are mixed with a crosslinking agent such as aminosilane are preferred. These can be applied in the form of solutions or emulsions. Generally, silicone resins have poor antistatic properties, so a small amount of cationic or anionic surfactant is added to impart antistatic properties. The amount of the treatment agent containing silicone resin as a main component is preferably 0.1 to 3% based on the dry weight of the fibers. 0.1
If the amount is less than % by weight, downlike flexibility cannot be imparted as described above. Furthermore, even if 3.0% by weight or more is added, the smoothness and flexibility do not improve much. The tow treated by the method of the present invention is a crimped tow that has been crimped and heat-set at 80°C or higher.
The crimp performance of the crimped tow is that the number of crimps is 5 crimps/25mm or more,
It is desirable that the degree of crimp is 5% or more. It is preferable that the number of crimps is 5 crimp/25 mm or more because bulkiness and compression recovery properties are excellent, and the fibers are less likely to come out from the side fabric while wearing the stuffed product.
It is possible and preferable to use a coarse side fabric that has a relatively large amount of ventilation, that is, an inexpensive side fabric. Although the method of the present invention can be used even when the number of crimps is less than 5 crimp/25 mm, the bulkiness and compression recovery properties are slightly reduced due to the small single yarn fineness. If the crimp ratio is less than 5%, bulkiness and compression recovery properties sufficient for filling will not reach a sufficiently satisfactory level. It is preferable that the crimp ratio is 5% or more because good bulkiness and compression recovery properties can be obtained. The crimp form can be a zigzag-like plane crimp using the push-in crimp method, a three-dimensional crimp that imparts anisotropy to the fiber cross section and develops latent crimp using composite spinning or asymmetric cooling spinning, or a mixture of both. But that's fine. Next, it is necessary to repeatedly relax and tension the heat-set crimped tow to produce tension fluctuations.
For example, this relaxation and tension may be applied in the length direction and width direction of the toe, but it is necessary to apply it at least in the length direction. A specific example of this is to provide a pair of rollers that rotate faster than the tow feeding speed between a pair of feed rollers that rotate at approximately the same speed and a pair of take-up rollers, and to rotate at least one of the rollers along the axis. You may also use a method such as using a cut roller to alternately apply tension and relaxation to the tow.
Publication No. 14169). Another specific example is a method in which a pair of feed rollers that rotate at periodically varying speeds and a pair of take-up rollers that rotate at a constant speed are provided, thereby alternately applying tension and relaxation to the tow. etc. may also be used. In this case, if a curved bar is provided between the feed roller and the take-up roller so that the convex part of the bar contacts the tow in the tow width direction, the tow is expanded more widely in the width direction.
It is a preferred embodiment to use such a curved bar in combination. The width of the opened tow is approximately twice the width of the tow before opening, and this is once converged and cut. The method for cutting the tow may be any method such as a circle cutter or a guillotine cutter. The fiber length is preferably 200 mm or less. Especially 20~76mm
is preferred. If it exceeds 200 mm, blow moldability deteriorates, causing troubles such as wrapping around the air blower fan, which is undesirable. When using synthetic fibers with a normal single filament fineness of 4 to 8 deniers, practical blow moldability cannot be obtained unless the fiber length is 35 mm or less, but in the present invention, even fine deniers of 3 deniers or less can be obtained. However, blow molding is possible even if the fiber length is increased to 200 mm. Fibers cut to 200 mm or less are immediately separated and opened by compressed air sprayed from a nozzle. As mentioned above, even if it is attempted to sufficiently open ordinary crimped short fibers having a fineness of 3 deniers or less using only this compressed air, it is impossible. By repeatedly relaxing and tensioning a crimped tow with an interfiber friction coefficient of 0.3 or less in the tow length direction to produce tension fluctuations, sufficient separation and opening, which could not be achieved with conventional methods, becomes possible. It is. Furthermore, in order to randomize the direction of the synthetic fibers that have been opened and cut into tows to create a more bulky filling, it is necessary to separate and open the fibers by blowing compressed air immediately after cutting. Hereinafter, the method of the present invention will be explained based on the drawings. FIG. 1 shows a conventional cotton manufacturing method after the tow crimping step. The crimped tow 1 is heat-set in a heat treatment machine 2 and then cut into staple fibers 4 by a cutter 3. FIG. 2 is a schematic side view showing an outline of one embodiment of the manufacturing apparatus according to the present invention. In FIG. 2, the crimped tow 1 is heat-set in a heat treatment machine 2 and then fed through a guide roller 5 to a series of tow gripping and transferring rollers, 6, 8, with one side between the rollers 6 and 8; A fiber opening body 7 is provided, the other being a cut roller 7' and an ordinary roller 7'' (this pair of rollers will be referred to as fiber opening rollers).
Fibers with irregular cross-sections with a fineness of 3 denier or less, especially those with protrusions on the outer periphery, for example those with the cross-sections shown in Figures 3 to 22, have a small contact area between the fibers, so misalignment easily occurs, so they are relatively difficult to use. The fiber opening property is good, and when a synthetic fiber with such a cross section is used, good fiber opening with a fiber opening rate of 80% or more is possible using the above-mentioned fiber opening body 7 and the gripping and transferring rollers 6 and 8. In addition, those with a hollow cross section are preferred because the cross section easily deforms during expansion and contraction, making it easier to open the fibers. The circumferential speed of the opening body 7 is normally set to be 1.5 to 7 times faster than the tow transport speed, that is, the circumferential speed of the rollers 6 and 8. When the crimped tow is temporarily held between the non-cutting surface of the cutting roller 7' and the ordinary cylindrical roller 7'', the crimped tow between the roller 6 and the opening body 7 becomes in tension and is opened. The fiber is in a relaxed state between the fiber 7 and the roller 8. Also, the crimped tow is temporarily not grasped between the cutting surface of the cutting roller 7' and the ordinary roller 7'', so the crimped tow is not crimped from the roller 6 to the roller 8. The entire toe becomes relaxed. As a result of this repeated action of tension and relaxation, the crimped tow is spread wider and more uniformly in the tow width direction. In FIG. 2, fibers with a circular cross-section yarn having a single filament fineness of 3 denier or less and having no protrusions cannot be sufficiently opened with the configuration of only the above-mentioned opening body 7 and gripping and transferring rollers 6 and 8. Hateful. In order to achieve sufficient separation and opening by the method of the present invention,
The cross section of the heat-set crimped tow fiber is limited to one having one or more protrusions along the fiber axis direction, as illustrated in FIGS. 3 to 22, for example. The tows opened in this manner are bundled through rollers 9, supplied to cutter 3, cut into desired fiber lengths, separated and opened by air nozzle 10 provided near the cutter. When the fibers are opened by the air nozzle 10, the short fibers are easily separated and opened because they have already been opened by the opening body 7. Therefore, the unloaded bulk of the cotton treated by the method of the present invention after unpacking is 35 cm ³ /g or more, which is extremely bulky, and the permeability in the blow molding method is extremely good when a normal blowing machine is used. Yes, the bulk of the filling,
Drapability, heat retention, and texture are also extremely good.
It has characteristics similar to high-quality natural feathers, with less than 20% small feathers and more than 80% down. Incidentally, the synthetic fiber obtained by the method of the present invention can also be used in combination with feathers. In the method of the present invention, before heat-setting the crimped tow or after heat-setting and opening the crimped tow, known moisture absorption, water absorption, flameproofing, antifouling treatment, etc. may be applied. Hereinafter, the present invention will be specifically explained with reference to Examples. Example 1 Polyethylene terephthalate having an intrinsic viscosity (IV) of 0.65 when dissolved in o-chlorophenol and measured at 25°C was made into a yarn having a cross-sectional shape as shown in Fig. 4 and a hollow ratio of 15%.
The fibers are spun from 240 spinnerets at a spinning temperature of 280°C and a spinning speed of 1000 m/min, which gives a drawn yarn denier of approximately 300,000 denier. Using a water drawing bath, draw at a drawing speed of 100 m/min and a draw ratio of 3.2, and apply a mixed solution of dimethylpolysiloxane and methylhydrodiene polysiloxane to the fiber by dry weight.
After applying it to a concentration of 0.3%, it was crimped using a push-in crimper and heat-set at 140°C for 30 minutes. The tow thus obtained was opened using a tow opening apparatus as shown in FIG. The diameter of the opening body 7 in Fig. 2 is 15 cm for both the cut roller 7' and the cylindrical roller 7'', and the cut roller has a cutting part 4.
I used one from several locations. The circumferential speed of the opening body 7 was set to four times the circumferential speed of the tow gripping and transferring rollers 6 and 8. The tow thus opened was re-focused and cut into 38 mm pieces, and immediately separated and opened using compressed air. The physical properties of the obtained fibers are as shown in the Examples column of Table 1. As shown in Table 1, the opening rate was extremely high. This was compressed to a specific volume of 2.5 cm ³ /g and packed into bales. When this product was left unpacked after being left for about 20 days, the unloaded bulk was extremely high at 40 cm ³ /g. When this product was passed through a normal feather blow molding machine, it was able to be blown without any problems. Example 2 Example 2 was carried out in the same manner as in Example 1 except that the fiber length was changed from 38 mm to 192 mm, and the results are shown in Example 2 in Table 1. Blow moldability is good if the fiber length is 200 mm or less. Comparative Examples 1, 2, 3, 4, 5 Comparative Example 1 in Table 1 shows the results of testing in Example 1 with a circular cross section and without tow opening. If tow opening is not performed, the opening rate is low, the unloaded bulk after unpacking is low, and the blow moldability is poor.
The blow molding machine frequently clogged, making it impossible to blow. In Example 1, the cross section was made circular and the test results were shown in Comparative Example 2 in Table 1 without crimping and heat setting. In this case, the silicone resin does not react and the coefficient of friction is high, and even if the crimp is increased during the push-crimping process, the crimp becomes stiff during the tow opening process, and the unloaded bulk after unpacking is low, resulting in poor blow moldability. It was hot. The texture was also rough and not very nice. Comparative Example 3 in Table 1 shows the results of Example 1 in which the cross section was circular and the number of crimps and crimp rate were set to be slightly low when applying indentation crimps. Due to the low number of crimp and low crimp ratio, the unloaded bulk after unpacking was low, making it impossible to blow into the product. The results of changing the fiber length from 38 mm to 228 mm in Example 1 are shown in Comparative Example 4 in Table 1. When the fiber length exceeds 200 mm, blow moldability deteriorates. In Example 1, separation by compressed air immediately after cutting,
The results without fiber opening are shown in Comparative Example 5 in Table 1. The unloaded bulk after unpacking was also insufficient, and the blow moldability was poor. Example 3 The same procedure as in Example 1 was carried out except that the cross section was shaped as shown in FIG. 3. The results are shown in Example 3 in Table 1. As in Example 1, the opening rate and the unloaded bulk after unpacking were high, and the blowing operation could be performed without any problem. Comparative Examples 6 and 7 Comparative Example 6 in Table 1 shows the results of carrying out the same procedure as in Example 3 except that octyl phosphatate potash was used instead of the silicone resin. Due to the high coefficient of friction, the unloaded bulk after unpacking was low and the texture tended to be rough, similar to Comparative Example 2. In Example 3, the single fiber fineness was set to 6 denier, which is outside the range of the present invention, and the tow was cut to 38 mm without being opened, and immediately opened using compressed air. The results are shown in Comparative Example 7 in Table 1. Although opening and blow molding were possible, the texture was very rough and far from down-like. 【table】

[Brief explanation of drawings]

Figure 1 is a diagram of the conventional cotton manufacturing process in which crimped tow is heat-set and then cut; Figure 2 is a diagram of the cotton manufacturing process of the present invention;
FIGS. 3 to 22 are diagrams showing examples of irregular cross sections. 1 is a crimped tow, 2 is a heat treatment machine, 3 is a cutter,
4 is a staple fiber after being cut, 5 is a guide roller, 6, 8, 10 are tow gripping and transferring rollers, 7 is a first opening roller, 7' is a cutting roller, 7'' is an ordinary roller, 9 is a second opening roller. A fiber roller, 9' is a second upper opening roller, 9'' is a second lower opening roller, 11 is a guide roller, and 12 is an air nozzle.

Claims (1)

[Claims] 1. A heat-set crimped tow having one or more protrusions in the fiber axis direction, a single yarn fineness of 3 denier or less, and an interfiber friction coefficient of 0.30 or less, relaxed at least in the longitudinal direction of the tow. A method for producing synthetic fibers for blow molding, characterized in that the fibers are subjected to a step of repeatedly applying tension to cause tension fluctuations, then cut into fibers having a length of 200 mm or less, and then immediately blown with compressed air to separate and open the fibers. 2. The manufacturing method according to claim 1, which is a modified hollow fiber having one or more protrusions in the fiber axis direction and having a hollowness ratio of 3 to 45%. 3. The manufacturing method according to any one of claims 1 to 2, which is a crimped tow in which a surface treatment agent containing silicone resin as a main component is added in an amount of 0.1 to 3.0% by weight based on the weight of the dry fibers. . 4. The manufacturing method according to any one of claims 1 to 3, wherein the fiber is a polyethylene terephthalate fiber.