JPH0244921B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a fiber having continuous layered cavities in the longitudinal direction of the fiber and a method for producing the same. More specifically, the present invention relates to a fiber having a layered cavity structure with good water absorption, flexibility and heat retention, and a method for producing the same. [Conventional technology] Synthetic fibers generally have high strength properties and good abrasion resistance and bending resistance, so they are excellent in durability, but they have the disadvantage of poor functionality such as water absorption and heat retention. be. Therefore, the current situation is that applications are restricted in fields that require these functions. For this reason, various improvements have been attempted up to now in order to overcome these drawbacks of synthetic fibers. A typical example is one in which the fiber itself has a capillary structure. For example, there is a method in which hollow fibers are made using a high molecular weight polymer having fiber-forming ability to which fine particles soluble in water or an organic solvent are added, and then the fine particles are eluted to make hollow fibers with fine pores. However, this method involves adding fine particles to a high molecular weight polymer and performing mixed spinning, so there are restrictions on the fine particles or the amount of the added amount from the viewpoint of spinning stability. There are disadvantages in that the continuity with the fiber surface is insufficient and the water absorption function of the fiber is also insufficient. On the other hand, in recent years, ultrafine fibers with a single filament fineness of 0.1d or less have become easily produced, and even if they are not hollow fibers, they can maintain a certain degree of water absorption through the capillary action of ultrafine fiber bundles or aggregates. Ta. However, on the other hand, ultrafine fibers have fatal drawbacks, especially when used for clothing, in that they do not have sufficient water absorption and are poor in colorability. [Problems to be Solved by the Invention] The purpose of the present invention is to solve one of the conventional problems of synthetic fibers, which is the lack of water absorption. The object of the present invention is to provide a fiber having a structure that is flexible and has a high heat retention property by increasing the air content inside the fiber, and furthermore to provide the above-mentioned fiber by a method with excellent spinning stability. [Means for Solving the Problems] The present inventors have conducted extensive research on fibers that have good water absorption, flexibility, and a structure with excellent heat retention properties, and as a result, they have gradually arrived at the present invention. . The gist of the present invention is as follows. That is, (1) layered portions 2 in which elongated cavities 1 that are continuous mainly in the longitudinal direction of the fibers exist in a layered manner, and constitute partition walls between the elongated layered cavities 1 and adjacent layered cavities 1; A fiber characterized by comprising the layered portion 2 and a skin portion 3 that thinly covers most of the outer periphery of the layered cavity 1. (2) When manufacturing a layered fiber in which A and B polymers are mutually arranged, a plurality of fluid channel forming pipe structures are arranged in series to allow the mutually arranged flows of A and B to flow out, and then , the A and B polymer mutually arranged fibers are passed through a lattice-shaped dividing funnel, most of the outer peripheral surface of which is covered with the A component, and then spun, and then a non-solvent or a weak solvent is used for the A component. However, a method for producing fibers having layered cavities, characterized in that component B is removed using a solvent capable of dissolving component B. (3) When manufacturing a layered fiber in which A and B polymers are mutually arranged, a plurality of fluid channel forming conduit structures are arranged in series to allow the mutually arranged flows of A and B to flow out, and then , A component covers the outer periphery of the mutually arranged flow of A and B, so that most of the outer periphery surface is A.
The A and B polymers are spun as fibers coated with the A and B polymers, and are then spun in a non-solvent or weak solvent for the A component but a solvent capable of dissolving the B component. This is a method for producing fibers having layered cavities, characterized by removing component B. In the present invention, the term "layered cavity" means that at least two elongated cavities exist in the cross section of the fiber, and the major axis of each cavity is at least one-third or more of the fiber cross-sectional width in the extension where the cavity is located. The length of the fiber is such that the cavity has continuity in the longitudinal direction of the fiber. In addition, a large number of concave and convex streaks that are continuous in the longitudinal direction on the outer peripheral surface of the fiber means that the difference in concavity and convexity is 0.2 μ or more, and if you focus on the convex part, there are four or more streaks, which is the result of normal fiber processing. This is different from friction scratches that occur during the process.
The fiber having layered cavities of the present invention, as shown in the partially cross-sectional perspective view of the fiber in FIG. Most of the outer periphery of the layered cavity 1 is made up of a thin skin part 3. Further, the outer circumferential surface of the fiber having layered cavities of the present invention includes a fiber having a large number of concavo-convex lines 4 extending in the longitudinal direction of the fiber. These uneven streaks are based on the above-mentioned layered fibers, and if the number of layered parts 2 is N, for example, when focusing on a convex part, approximately 2XN streaks are generated. At the outer periphery of the fiber, the part close to the cavity is mainly in the form of an extremely thin film of 2μ or less, and cracks or depressions 5 are formed in some parts, as shown in the cross-sectional view of the fiber in FIG. , these cracks or depressions 5 have an open structure that leads substantially to the cavity inside the fiber. Therefore, the layered cavities that extend in the longitudinal direction of the fibers, the openings or thin films caused by cracks and depressions on the surface that are the contact points between the cavities and the outer circumferential surface of the fibers, and the large number of uneven streaks act as capillaries. ,
The structure as a whole is convenient for absorbing water and releasing absorbed water. Further, since the fiber of the present invention is composed of a layered portion and a hollow portion inside, it is flexible because it easily deforms freely in response to external stress.
Furthermore, since the fiber itself contains a large amount of air, it has an effective structure for heat retention. The fiber having layered cavities as described above can be obtained, for example, as follows. That is, the pipe structure for forming a fluid flow path shown in Japanese Patent Publication No. 1048/1988 is made by using A and B polymers having fiber-forming ability, so as not to cause significant rotation of the fluid. The fibers obtained by spinning the fibers of the A and B polymeric mutual arrays having a skin, which are the intermediates of the present invention, in spinning devices arranged in series, and then removing one component of the polymeric mutual arrays. It will be done. By arranging the fluid channel forming pipe structures in series, it is possible to obtain, for example, a fluid laminate in which the polymers A and B are laminated separately in the machine layer. When N stages of forming conduit structures are used, 2×N layers of A and B polymers can be formed. The fluid channel forming pipe structure has the function of sequentially and alternately arranging fluid in layers in this way. FIG. 3 is a cross-sectional view of a polymer mutual array fiber having a skin, which is an intermediate of the present invention, and shows A component 6 and B component 6.
Components 7 are arranged alternately in layers, and the outer periphery is surrounded by a thin skin (epidermis) 8 of component A. The A component 6 used here is a polymer effective as a practical fiber, and the B component 7 has a solubility in a solvent different from that of the A component, and is used as an intermediate to obtain a polymer interlayer array fiber with a skin. It is a high molecular weight polymer that plays a critical role and is removed in a subsequent process. Polymer interlayer fibers having a skin as shown in FIG. 3 can be obtained by providing special equipment in the spinning pack as follows. One of these is the installation of a lattice-shaped separator that crosses and cuts the laminar flow of A and B mutually arranged flows flowing out from a group of pipe structures for forming fluid flow paths in the spinning pack. , and the other, as shown in the schematic cross-sectional view of the spinning pack in FIG. Until then,
A from the coating discharge port 11 of another polymer array flow so as to cover the outer periphery of the mutually array flow 9 of the A and B components.
This is a method of extruding ingredients. The former method, i.e., the separator downstream of the group of conduit structures for forming fluid flow paths, is achieved by arranging a lattice-like dividing funnel with sharp corners at the top of the octopus branch pipe leading to the porous mouthpiece. be done.
The method of discharging the A and B mutually aligned flows using this octopus branch is as follows:
Although the number of layers consisting of A and B is reduced, this method is preferable from the viewpoint of economy and productivity, and is also preferable from the viewpoint of imparting unevenness to the outer peripheral surface of the fiber according to the present invention. Furthermore, it is particularly preferable that the A and B polymers are selected in this method so that the melt viscosity at the spinning temperature is in the relationship A>B or the weight ratio of the A and B components is in the relationship A>B. This relationship is based on A and B where the outer peripheral surface of the fiber is covered with the A component.
These conditions make it easy to obtain fibers with mutually arranged polymers. On the other hand, from the coating discharge port 11 of the polymer array flow shown in the latter FIG.
The extrusion amount of the components is 3 to 30 parts by weight per 100 parts of the laminar A and B component mutually arranged flow,
Preferably it is 7 to 20 parts. If the amount of extrusion is too large, not only will the skin become thick and it will be difficult to remove component B, but also the continuity between the layered cavities and the fiber surface will be weakened, which is not preferable. On the other hand, if the amount is too small, the fiber of the present invention cannot be obtained due to the inability to form a skin, so it is necessary to adjust the amount of extrusion as appropriate. The ratio of the A component and the B component of the A and B component mutual array, so-called A and B alternating layered portion is 85:15 by weight.
It can range from 25:75 to 25:75, but spinning stability,
From the formation of layered cavities after component removal, A and B are
A preferred range is 70:30 to 40:60. From the ratio of the A and B components in the layered portion, the area occupied by the layered cavity in the cross section of the fiber according to the present invention should be approximately equal to the area occupied by the B component in the layered portion. Usually it is 5 to 50%. The polymers of component A used in the present invention include polyethylene terephthalate (hereinafter referred to as PET) and its copolymer, polybutylene terephthalate (hereinafter referred to as PBT), nylon 6, nylon 66,
It is a high molecular weight polymer such as polyethylene or polypropylene, and one or more types thereof are used. The polymer of component B is polystyrene (hereinafter referred to as
PST), 2-ethylhexyl acrylate copolymer PST, 5-sodium sulfoisophthalate copolymer PET, nylon 6, nylon 66,
It is a high molecular weight polymer such as polyvinyl alcohol, and one or more types thereof are used. If component A and component B have fiber-forming ability,
Although not limited to the above, PET, PBT, nylon 6, and nylon 66 are preferable as component A from the viewpoint of practical performance, and among them, PET is a particularly preferable polymer because of its ability to form layered cavities. Further, as component B, PST, 2-ethylhexyl acrylate copolymer PST, and 5-sodium sulfoisophthalate copolymer PET are particularly preferred polymers from the viewpoint of processability. The B component can be removed from the A and B polymer mutual array fibers having a skin by performing dry heat stretching, wet heat stretching, or liquid bath stretching using a conventionally known method. Any fibrous structures such as knitted fabrics, woven fabrics, nonwoven fabrics, and strings can be used. From the viewpoint of handling and efficiency, it is particularly preferable to remove the fiber structure. In this case, it goes without saying that the fiber structure may contain fibers other than those of the present invention. The removing agent for component B must be selected appropriately within a range that does not affect the performance of component A as a fiber. For example, when component B is PST and its copolymer, trichlorethylene, perchlorethylene, Solvents of chlorinated organic compounds such as carbon tetrachloride are generally used, and in the case of 5-sodium sulfoisophthalate copolymerized PET, treatment with an alkaline solution, so-called alkali reduction processing, is performed. Further, although the device for removing component B varies depending on the form of the treated yarn, a mangle, a vibrowasher, a dyeing machine, etc. can be used, and the device may be selected as appropriate. Thus, the fiber obtained by removing component B is
As shown in FIGS. 1 and 2, layered cavities are formed in the cross-sectional view of the fibers, or the outer circumferential surface of the fibers has uneven streaks that are continuous in the longitudinal direction of the fibers. The structure is suitable for flexibility and heat retention. If the product from which the above B component has been removed remains in a yarn state, it can be processed into fiber structures such as knitted fabrics, woven fabrics, non-woven fabrics, and strings depending on the purpose, and dyed or otherwise finished as necessary. By processing, it is possible to provide a fiber structure with excellent functionality including water absorption. In addition, the fibers having layered cavities of the present invention can be stretched, knitted fabrics, nonwoven fabrics, processed into strings, etc., raised,
The layered cavities are likely to be partially crushed due to physical external forces during dyeing and other finishing processes or merging during spinning, but if the fibers are mainly the fibers of the present invention, their effectiveness is limited. There is almost no impact. [Examples] Next, the present invention will be specifically explained with reference to Examples, but the present invention is not limited to these. Example 1 A spinning pack was used, which was equipped with 6 pipe structures for forming fluid flow channels arranged in series, a lattice-like dividing funnel and branch pipes divided into 6 x 3 at the bottom, and an 18-hole spinneret. , PET with a melt viscosity of 3000 poise at a spinning temperature of 285°C and 2-ethylhexyl acrylate copolymer PST with a melt viscosity of 450 poise at a weight ratio of 50:50 from the upper part of the fluid channel forming pipe structure. The fibers of the polymer mutual array were spun. Next, dry heat drawing was performed at 85°C to obtain a drawn yarn with a single yarn fineness of 3d. Subsequently, this drawn yarn was made into a skein shape, and the 2-ethylhexyl acrylate copolymer PST was sufficiently dissolved and removed by repeatedly immersing the yarn in trichlorethylene at room temperature and squeezing it with a mangle. When the treated fibers were observed at several locations in the longitudinal direction of the fibers using a scanning electron microscope,
An epidermis was formed on the outer peripheral surface. In addition, 2 to 10 elongated cavities were formed in the cross section of the fiber, forming layered cavities. Furthermore, on the outer peripheral surface of the fiber, a large number of continuous unevenness lines with a difference of 0.2 to 1.5μ are formed in the longitudinal direction of the fiber, and there are also cracks or depressions that partially communicate with the layered cavity. was recognized. Example 2 Instead of providing a lattice-shaped split funnel downstream of the six fluid channel forming pipe structures arranged in series, a one-hole mouthpiece discharge hole as shown in FIG. A spinning pack provided with a circular slit outlet was used so as to cover the outer periphery of the mutually arranged polymer flow flowing out from the flow path forming pipe structure. From the upper part of the fluid flow path forming pipe structure, the spinning temperature is
Same as PET with melt viscosity of 3000 poise at 285℃
450 poise 2-ethylhexyl acrylate copolymerized PST and 3000 poise PET from the coating outlet of the polymer mutually aligned flow are fed in a weight ratio of 50:50:15, respectively. The reciprocal array fibers were spun. Next, dry heat stretching was carried out at 85℃, and the single yarn fineness was
A drawn yarn of 3.1 d was obtained. Subsequently, this drawn yarn was made into a skein, and the 2-ethylhexyl acrylate copolymer PST was sufficiently dissolved and removed by repeatedly immersing the yarn in trichlorethylene at room temperature and squeezing it with a mangle. When the fibers treated in this manner were observed using a scanning electron microscope, it was found that, as in Example 1, the outer periphery of the layered fibers was bonded in a thin skin-like manner, and layered cavities were formed in the cross section of the fibers. Furthermore, although the outer peripheral surface of this fiber is slightly shallower overall than that of Example 1, there are many continuous uneven lines in the longitudinal direction of the fiber, and cracks or depressions that partially lead to layered cavities. was formed. Comparative Example 1 PET and 2-ethylhexyl acrylate copolymer PST of Example 1 were mixed in weight ratio without providing a lattice-like dividing funnel downstream of the six fluid channel forming pipe structures arranged in series. The fluid flowed out from the conduit structure for forming a fluid flow path at a ratio of 50:50, and was then spun using a one-hole spinneret, as described in Example 1 below.
In the fibers processed in the same manner as above, no layered cavities were formed. Example 3 The undrawn yarn spun in Example 1 was tow-stretched in a solution at 80°C and crimped, resulting in a yarn with a cut length of 51 mm, a single yarn fineness of 3.2 d, and a number of crimps of 13 threads/inch. Created raw cotton. Next, a web was prepared through a carding and cross-wrapping process, and 2000 pieces/cm ² of needle punching was performed to obtain a non-woven fabric made of polymer interlayer array fibers with a basis weight of 510 g/m ² . Next, this nonwoven fabric was shrink-treated with hot water at 85°C and dried, and then repeatedly soaked in trichlorethylene and squeezed with a mangle to remove the 2-ethylhexyl acrylate copolymerized PST in the fibers constituting the nonwoven fabric. Sufficiently removed. When the cross section of the nonwoven fabric treated in this way was observed using a scanning electron microscope, it was found that the fibers were partially deformed, but the fiber cross section and outer peripheral surface were
The structure was almost the same as that of Example 1. Next, cut this non-woven fabric to 2 cm wide and 15 cm long, and place one end of the non-woven fabric 5 cm long into a beaker filled with water.
The other end of the nonwoven fabric was immersed in the beaker, and the other end was allowed to hang outside the beaker, and the weight of water dripping in 2 minutes from the hanging nonwoven fabric was measured. These results are shown in Table 1 together with the results of Comparative Examples 2 and 3 of other PET fibers prepared by needle punching in the same manner. As is clear from the results in Table 1, the nonwoven fabric using the fibers of the present invention exhibited significantly better water absorption than that of the comparative example. Regarding the texture of the nonwoven fabric, the nonwoven fabric made of the fibers of the present invention had a good feel and a soft texture compared to the nonwoven fabric of Comparative Example 2, which had a similar fineness.

〔Effect of the invention〕

As mentioned above, the fibers of the present invention have a special cross-sectional structure and an associated special surface structure, so they are particularly suitable for the field of clothing, which requires water absorption, flexibility, heat retention, etc. It can be used as a highly functional material. On the other hand, in the manufacturing method of fibers having capillary tubes which are effective for water absorption, etc., the method using the conduit structure for forming a fluid flow path according to the present invention has extremely stable spinnability and has layered cavities having the above functions. can be provided extremely effectively.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing a partial cross section of the fiber of the present invention, Fig. 2 is a sectional view taken along line X-X' in Fig. 1, and Fig. 3 is a polymer having a skin, which is an intermediate of the present invention. Cross-sectional view of inter-arrayed fibers. FIG. 4 is a schematic cross-sectional view of a spun pack of polymeric inter-arrayed fibers. 1: layered cavity, 2: layered part, 3, 8: epidermal part,
4: Uneven lines, 5: Cracks or depressions, 6: A component, 7: B component, 9: Polymer mutual alignment flow, 10:
Mouth discharge hole, 11: discharge port for coating of polymer array flow.

Claims (1)

[Scope of Claims] 1 A layered portion 2 in which elongated cavities 1 that are continuous mainly in the longitudinal direction of the fibers exist in a layered manner, and constitute partition walls between the elongated layered cavities 1 and adjacent layered cavities 1. , and a skin part 3 that thinly covers most of the outer periphery of the layered cavity 1 and the layered part 2. 2. Claim 1, in which the outer peripheral surface of the fiber has a large number of concave and convex lines that are continuous in the longitudinal direction of the fiber.
A fiber having layered cavities as described in Section 1. 3. When producing a layered fiber in which the polymers A and B are mutually arranged, a plurality of fluid channel forming conduit structures are arranged in series to allow the mutually arranged flows of A and B to flow out, and then a lattice is formed. A, in which most of the outer peripheral surface is coated with the A component by passing through a shaped dividing funnel;
B The polymer interlayer array fibers are spun, and then A
Although it is a non-solvent or weak solvent for the component, B
A method for producing fibers having layered cavities, characterized in that component B is removed using a solvent capable of dissolving the components. 4. The method for producing a fiber having layered cavities according to claim 3, wherein the melt viscosities of the polymers A and B at the filament temperature satisfy the relationship A>B. 5. When producing a layered fiber in which the polymers A and B are mutually arranged, a plurality of fluid channel forming pipe structures are arranged in series to allow the mutually arranged flow of A and B to flow out, and then The outer periphery of the mutually arranged stream of A and B is coated with the component, and the A and B polymer mutually arranged fibers with most of the outer circumferential surface covered with the A component are spun, and then the A component is A method for producing fibers having layered cavities, characterized in that the B component is removed using a non-solvent or weak solvent for the B component, but a solvent capable of dissolving the B component.