JPH05230716A - Inorganic particle-containing conjugate fiber - Google Patents

Abstract

PURPOSE:To obtain the subject fiber having a fineness lower than the general fineness and excellent in spinnability and fiber performance by forming the fiber of a specified polymer layer component containing a large amount of inorganic fine particles and a protecting fiber-forming thermoplastic polymer layer component. CONSTITUTION:The objective composite fiber is composed of (A) a fiberforming thermoplastic protecting polymer layer component and (B) a polymer layer component containing 5 to 85wt.% inorganic fine particles and >=60wt.% of the perimeter of the fiber cross-section is composed of the component (A). The single yarn fineness is <=8 denier and the polymer constituting the component (B) is a block copolymer having 30000 to 250000 number-average molecular weight, composed of a polyaromatic vinyl block (Number-average molecular weight of one block is 4000 to 50000) and a polyconjugated diene block (Number- average molecular weight of one block is 10000 to 150000 and >=30% of conjugated diene-derived double bonds is hydrogenated) and containing >=0.1wt.% hydroxy-t-butylphenyl-based compound having the hydroxyl group at the ortho position to the butyl group.

Description

Detailed Description of the Invention

[0001]

INDUSTRIAL APPLICABILITY The present invention contains a large amount of inorganic fine particles such as UV-shielding fibers and white conductive fibers, and, despite containing a large amount of inorganic fine particles,
The spinnability is good and the fineness of the fiber is 8
For fibers that are less than or equal to denier.

[0002]

2. Description of the Related Art In recent years, in order to impart various properties to fibers, a method has been used in which inorganic fine particles are selected according to the properties to be imparted, and the inorganic fine particles are kneaded into a fiber constituent polymer and spun. For example, white conductive metal oxide is selected as the inorganic fine particles, and kneaded into a fiber-constituting polymer and spun to obtain white conductive fibers. Also, as the inorganic fine particles, UV-shielding inorganic fine particles are selected, and the fiber-constituting polymer is selected. An ultraviolet-shielding fiber is obtained by kneading and spinning it. Further, by selecting a specific pigment as the inorganic fine particles, kneading this into a fiber constituent polymer, and spinning it, a dyed fiber having a specific color tone can be obtained.

However, in such an inorganic fine particle-containing fiber, it is necessary to increase the addition amount of the inorganic fine particles in order to sufficiently exert the effect of adding the inorganic fine particles. For example, in the case of white conductive fibers, if the amount of white conductive metal oxide added is less than or equal to a predetermined amount, the added metal oxide will not be linked and the conductive performance will not be obtained. Similarly, in the case of UV-shielding fibers, if the amount of UV-shielding inorganic fine particles added is small, a satisfactory UV-shielding effect cannot be obtained. Therefore, there is a demand for a technique of adding a large amount of inorganic fine particles to fibers.

Generally, when a large amount of inorganic fine particles are added to a fiber constituent polymer, the spinnability of the polymer is rapidly deteriorated.
Furthermore, when a large amount of inorganic fine particles are present on the fiber surface, the surfaces of guides, rollers, stretching plates and travelers during the fiber manufacturing process will be scraped by the inorganic fine particles exposed on the fiber surface, making these devices unusable. It becomes possible, and further, when the production of fibers is continued by using such a device whose surface is worn out, many yarn breakages and fluffs occur. Therefore, in the case of adding a large amount of inorganic fine particles to the fiber, it is necessary to prevent the inorganic fine particles from existing on the fiber surface. As a specific method therefor, the fiber is a core-sheath type composite fiber. A method of adding the inorganic fine particles to the polymer constituting the core is conceivable. However,
In order to obtain a sufficient addition effect simply by adding inorganic fine particles to the polymer that constitutes the core, a larger amount of inorganic fine particles must be added to the core component polymer, which contains an increasing amount of inorganic fine particles. The spinnability and spinnability of the core component polymer are required.

In order to improve the spinnability of the core component polymer containing a large amount of inorganic fine particles in the core-sheath type composite fiber,
A technique of using a thermoplastic elastomer as such a polymer has been proposed (JP-A-2-289118). That is, using conductive metal oxide particles as the inorganic fine particles, as the core component polymer, polystyrene-polyisoprene-polystyrene block copolymer, polystyrene-polybutadiene-polystyrene block copolymer, polystyrene-polyisoprene block copolymer,
Also, by using these hydrogenated products, the spinnability of the core component polymer is good even when a large amount of inorganic fine particles are added. Certainly, when the technique described in this publication is used, thick fibers having a denier of 10 denier or more can be produced without problems, but for fibers having a fineness of 8 denier or less, which is generally used for clothing, A higher spinnability is required, and it is difficult for the technique described in the above publication to stably produce a fiber having such a fineness in a high yield, and the quality of the obtained fiber is not satisfactory. Further, when a large amount of inorganic fine particles are contained in the fiber, even if such a fiber is dyed, the color tone is deep and there is no vividness, and a product having a high-grade color tone cannot be obtained.

[0006]

The object of the present invention is a fiber having a fineness of 8 denier or less, which is suitable for use in general clothing, and is spun despite containing a large amount of inorganic fine particles. It is to provide a fiber having excellent properties and excellent fiber performance. Another object of the present invention is to provide a fiber which can be dyed to give a product having a clear color tone.

[0007]

[Means for Solving the Problems] An important problem in containing a high concentration of inorganic fine particles in a fiber having a fineness of 8 denier or less is a problem due to clogging of the filtering material or yarn breakage in the spinning process. For example, the spinning property is deteriorated. Further, even if the fiber can be spun, there are many occurrences of yarn breakage in the drawing process. Further, there is a problem in post-processability when producing a fabric such as a woven fabric and a knitted fabric, and in particular, there is a problem that a guide or the like is worn. Even if fibers are obtained, there are problems in fiber performance such as homogeneity. In the present invention, these problems have been solved by using a specific block copolymer containing a specific compound as a base polymer containing a high concentration of inorganic fine particles.

That is, the present invention comprises a protective polymer layer component (A) made of a fiber-forming thermoplastic polymer and a polymer layer component (B) containing inorganic fine particles and having a single yarn fineness of 8 denier or less and A fiber in which 60% or more of the circumference of the fiber cross section is the component (A),
The amount of the inorganic fine particles in the component (B) is 5 to 85% by weight, and the hydroxy group in which the hydroxyl group is in the ortho position with respect to the butyl group in the component (B) is used.
The tert-butylphenyl compound is added in an amount of 0.1% by weight or more based on the polymer constituting the component (B), (II
I) The polymer constituting the component (B) is a polyaromatic vinyl block in which one block has a number average molecular weight of 4,000 to 50,000 and one block has a number average molecular weight of 1
A block copolymer composed of 000 to 150,000 polyconjugated diene blocks, wherein 30% or more of double bonds based on the conjugated diene of the polyconjugated diene block are hydrogenated, and the number average molecular weight is 30,000 to 2,500.
00 is a composite fiber.

As the compound forming the polyaromatic vinyl block which is the first constituent of the block copolymer used in the present invention, an anion-polymerizable aromatic vinyl monomer such as styrene, 1-vinylnaphthalene or 2-vinyl is used. Naphthalene, 3-methylstyrene, 4-propylstyrene, 4-cyclohexylstyrene, 4-dodecylstyrene, 2-ethyl-4-benzylstyrene, 4- (phenylbutyl) styrene and the like can be mentioned, and these are one kind or two kinds. The above is used.

Examples of the compound forming the polyconjugated diene block which is the second component include isoprene, butadiene, piperine and the like, and one or more of these are used.

The block copolymer used in the present invention is mainly composed of a polyaromatic vinyl block and a polyconjugated diene block, and the functional group such as a carboxyl group, a hydroxyl group or an acid anhydride is present in the molecular chain or at the terminal of the molecule. It may have a group. Specific examples of the block copolymer used in the present invention include, for example, a hydrogenated product of a polystyrene-polybutadiene-polystyrene block copolymer (hereinafter abbreviated as SBS) and a polystyrene-polyisoprene-polystyrene block copolymer. (Hereinafter abbreviated as SIS) hydrogenated product, polystyrene-polyisoprene block copolymer (hereinafter abbreviated as SI) hydrogenated product, poly α-methylstyrene-polyisoprene-poly α
Hydrogenated block copolymer of methylstyrene, hydrogenated block copolymer of poly α-methylstyrene-polybutadiene-poly α-methylstyrene, poly α-
Examples thereof include hydrogenated products of block copolymers of methylstyrene-polyisoprene, and hydrogenated products of triblock copolymers having polyaromatic vinyl blocks as both end blocks are particularly preferable. Among them, hydrogen of the above SIS is preferable. Additives are preferred.

The block copolymer used in the present invention is
It is necessary that 30% or more of the double bonds based on the conjugated diene of the polyconjugated diene block be hydrogenated. If the hydrogenation rate is less than 30%, the block copolymer is thermally decomposed during melt spinning.
In addition, the hydrogenation rate referred to here is a carbon-carbon which is a double bond based on the conjugated diene contained in the block copolymer.
Means the proportion of carbon unsaturated double bonds that are hydrogenated,
Obtain the iodine value before hydrogenation and the iodine value after hydrogenation,
It is calculated by calculating the percentage of the latter with respect to the former. More preferably, the hydrogenation rate is 50% or more.

The number average molecular weight of the block copolymer used in the present invention must be in the range of 30,000 to 250,000. When the number average molecular weight is less than 30,000, the melt viscosity of the polymer during spinning becomes too low, the single yarn breakage and the yarn breakage frequently occur during spinning, and the uniformity of the fiber deteriorates. In particular, when a high melting point polymer such as polyester is used as the protective polymer component to obtain a composite fiber, it becomes a serious problem. On the other hand, when the number average molecular weight exceeds 250,000, the melt flowability of the polymer is insufficient and the spinnability deteriorates. From this point, the number average molecular weight of the block copolymer is preferably in the range of 40,000 to 200,000.

The number average molecular weight of one block of the polyaromatic vinyl block constituting the block copolymer is 400.
The number average molecular weight is 4000.
If it is less than the above range, the cohesive force of the polymer is lowered, the rubber-like stretchability becomes insufficient, and it becomes difficult to form the target fiber. On the other hand, when the number average molecular weight exceeds 50,000, the melt viscosity of the block copolymer becomes too high and the thermoplasticity is impaired,
Melt fluidity decreases and spinning becomes difficult. Further, the number average molecular weight of one block of the polyconjugated diene block constituting the block copolymer is in the range of 10,000 to 150,000, and when the number average molecular weight is less than 10,000, the elasticity as a polymer becomes insufficient, and the purpose It becomes difficult to form fibers. On the other hand, if the number average molecular weight exceeds 150,000, the melt flowability of the polymer is lowered and spinning becomes difficult. From these points, the number average molecular weight of one block of the polyaromatic vinyl block is preferably in the range of 5,000 to 40,000, and the number average molecular weight of one block of the polyconjugated diene block is preferably in the range of 15,000 to 130000.
The number average molecular weight is determined by the conventional GPC method (Gel Parmea).
ition Chromatography).

The proportion in the polyaromatic vinyl block copolymer is preferably in the range of 5 to 80% by weight. If the proportion of the polyaromatic vinyl block in the block copolymer is less than 5% by weight, the cohesiveness of the polymer is reduced, the stretchability of the polymer is deteriorated, and the handleability is also reduced, which makes fiber formation difficult. .. On the other hand, when it exceeds 80% by weight, the viscosity of the polymer is remarkably increased, so that spinning tends to be difficult.

Further, the block copolymer used in the present invention has an MFR (Melt Flow Rate) value of 5 g /
It preferably has a melt flowability characteristic of 10 minutes or more. When the MFR value is less than 5 g / 10 minutes, the melt fluidity deteriorates when the inorganic fine particles are added at a high concentration, and it tends to be difficult to obtain a composite fiber having a denier of 8 or less. The upper limit of the MFR value is not particularly limited, but from the viewpoint of spinnability, productivity, etc., it is preferably 100 g / 10 minutes or less, and particularly preferably 5 to 80 g / 10 minutes. The MFR value here is ASTM D-
It is a value measured by the measuring method of 1238 under the condition of 200 ° C. and a load of 10 kg. The MFR value specified in the present invention is the value of the block copolymer in the fiber after spinning. Therefore, even if the MFR value before spinning is lower than the above value, it can be said to be suitable for the present invention as long as it satisfies the above value during the spinning process. The MFR value of the block copolymer is
It is determined by the molecular weight of the block copolymer, the weight ratio of polyaromatic vinyl block / polyconjugated diene block, the molecular chain length of each block, and the like. Therefore, the block copolymer used in the present invention has such a molecular weight, a weight ratio of blocks, a molecular chain length of each block, etc.
It is preferable that the MFR value is within the above range.

The block copolymer used in the present invention can be obtained by the following various known methods. A compound that forms a polyaromatic vinyl block using an alkyllithium compound as an initiator, a method of sequentially polymerizing a compound that forms a polyconjugated diene block, a compound that forms a polyaromatic vinyl block, and a compound that forms a polyconjugated diene block Method of polymerizing and coupling with a coupling agent, using a dilithium compound as an initiator,
Examples thereof include a method of sequentially polymerizing a compound forming a polyaromatic vinyl block and a compound forming a polyconjugated diene block.

Furthermore, in the present invention, the block copolymer is a compound which is a hydroxy-tert-butylphenyl compound and the hydroxy group is located in the ortho position with respect to the butyl group (hereinafter referred to as phenol compound. It is necessary to add 0.1% by weight or more to the block copolymer. The phenolic compound is generally used as an antioxidant, and many kinds of antioxidants are known in addition to the phenolic compound. However, the phenolic compound is used in spinning the block copolymer. It has a remarkable effect on stability. In general, when inorganic fine particles are added, the thermal decomposability of the block copolymer is promoted, but the phenolic compound also has an unexpected effect of greatly suppressing this promoting effect. It is considered that this action of the phenolic compound brings about excellent spinnability even though the inorganic fine particles are contained in a large amount. When the amount of the phenolic compound added is less than 0.1% by weight, the above-mentioned excellent effects cannot be obtained. The upper limit is not particularly limited, but is preferably 10% by weight or less, and particularly preferably 0.2 to 5% by weight.

The phenolic compound preferably used in the present invention is a compound represented by the following chemical formula 1.

[Chemical 1] In the above formula, M represents an organic group, R represents an alkyl group, and n represents an integer of 1 to 3. However, when n is 2 or more, R may be the same or different. Specific compounds include the following compounds.

[Chemical 2]

[Chemical 3]

[Chemical 4]

[Chemical 5]

[Chemical 6]

[Chemical 7]

[Chemical 8]

[Chemical 9]

[Chemical 10]

[Chemical 11]

[Chemical 12] Among them, the compound suitable for the present invention is the compound represented by the above chemical formula 2.

The phenolic compound may be added to the block copolymer at any time, and during the production of the block copolymer,
It can be added and kneaded after the production or simultaneously with the inorganic fine particles. When the composite fiber of the present invention is spun, the block copolymer, the phenolic compound and the inorganic fine particles may be uniformly kneaded, and the addition timing is not particularly limited.

In the composite fiber of the present invention, inorganic fine particles are added to the block copolymer as described above. The amount of the inorganic fine particles added varies depending on the intended fiber, but the present invention is intended to solve the problem in the case of adding a large amount of the inorganic fine particles to the fiber, and thus the inorganic fine particles are included. It must be added in an amount of 5% by weight or more based on the block copolymer composition. 5
If it is less than wt%, there is no problem to be solved by the present invention. The upper limit of the amount added is not particularly limited, but about 85% by weight or less is still preferable from the viewpoint of spinnability. More preferably, it is in the range of 10 to 70% by weight.

The type of the inorganic fine particles to be added varies depending on the intended fiber. For example, when the objective is to obtain an ultraviolet ray-shielding fiber, fine particles that reflect or absorb ultraviolet rays, that is, substantially do not transmit ultraviolet rays. Fine particles are used. Representative examples thereof include inorganic compounds such as titanium dioxide, zinc oxide, magnesium oxide, alumina, silicon dioxide, barium sulfate, calcium carbonate, sodium carbonate, talc and kaolin, and various treated fine particles of the inorganic compound. One kind or a mixture of two or more kinds can be used. More preferably,
Titanium dioxide, zinc oxide and alumina. Particularly preferred is titanium dioxide. The amount added is preferably in the range described above from the viewpoint of ultraviolet shielding property. In addition to this, for the purpose of obtaining brightly colored fibers, for example, an inorganic pigment is used as the inorganic fine particles. Further, when it is intended to obtain a conductive fiber, a conductive metal oxide or a metal powder is used as the inorganic fine particles, and when the purpose is to obtain a magnetic fiber, iron, cobalt,
Metals such as nickel and magnetic powders of these oxides or ferrites are used as the inorganic fine particles.

The average particle size of the inorganic fine particles is preferably 5 μm or less, more preferably 1 μm or less. If the particle size is too large, problems such as clogging of the filter during spinning and yarn breakage occur, and further yarn breakage occurs during drawing. The average particle diameter referred to here is a particle size distribution measuring device (CAPA-50 manufactured by Horiba, Ltd.).
It is a value measured using 0). Furthermore, in the present invention, in order to enhance the spinnability, it is preferable to add a metal salt of stearic acid or a titanium-based coupling agent to the block copolymer containing inorganic fine particles, and particularly magnesium salt of stearic acid or calcium. Salts, zinc salts and the like are preferable, and magnesium stearate is preferable particularly when the inorganic fine particles are titanium oxide or those containing titanium oxide. The addition amount of these compounds is preferably in the range of 1 to 10% by weight with respect to the inorganic fine particles.

Various methods can be used for incorporating the inorganic fine particles into the block copolymer. For example, the block copolymer polymer and the inorganic fine particles are kneaded and molded by a twin-screw kneading extruder or the like. , A method of producing a high-concentration masterbatch, diluting the masterbatch with the block copolymer so that the concentration becomes a predetermined concentration at the time of spinning, and then spinning. Further, when the block copolymer and the inorganic fine particles are kneaded, it is preferable to add various dispersion aids because the dispersibility becomes good.

The composite fiber of the present invention comprises, as one component, a block copolymer containing inorganic fine particles and a phenolic compound as described above (hereinafter referred to as component B), and a fiber-forming thermoplastic polymer (hereinafter referred to as component A). It is obtained by carrying out a composite spinning using (as referred to) as another component. The composite cross-sectional shape at that time is preferably such that the component A occupies 60% or more of the fiber surface circumference. If it is less than 60%, the proportion of the component B exposed on the fiber surface increases, and the component B contains a large amount of inorganic fine particles, so that a guide or roller is used during the fiberizing step during yarn making or during post-processing such as weaving. It becomes unfavorable because it causes severe friction and causes troubles such as yarn breakage.

Various composite forms of the component A and the component B can be cited, and typical examples are those shown in FIGS. 1 to 8. 1 core,
2 is a three-core, FIG. 3 is a four-core core-sheath structure fiber, FIG. 4 is a three-layer concentric circle, FIGS. 5 and 6 are partially exposed core-sheath structures, and FIGS. 7 and 8 are split-type composite structures. Is. Depending on the combination of component A and component B, the structure of FIGS.
Peeling may occur at the interface between the components, and the structures of FIGS. 5 and 6 cannot sufficiently eliminate friction of guides, rollers, and the like. From the point that it is possible to further prevent friction and thread breakage of guides and rollers, and to prevent peeling between polymers, a core like that shown in FIGS. 1 to 4 in which the core polymer is completely covered by the sheath polymer. A sheath structure is preferred. In these figures, the hatched portion is the component B, and the non-hatched portion is the component A.

The composite weight ratio of component A and component B is preferably 20:80 to 80:20, more preferably 30: 7.
0 to 76:24. If the ratio of component A is too small,
It is not preferable because the fiber strength is reduced. Also component A
If the ratio of B is too large, component B containing inorganic fine particles
This is not preferable because the effect of 1 cannot be fully exhibited.

Component A, the other composite component of the present invention
As for nylon 6, nylon 66, nylon 61
0, nylon 12, nylon 11, nylon 4, nylon 46 and other polyamides, polyethylene terephthalate, polybutylene terephthalate, polyhexamethylene terephthalate and other polyesters, polyethylene,
It is selected from polyolefins such as polypropylene and the like, but in terms of practical performance as a fiber, particularly a polyester polymer having polyethylene terephthalate or polybutylene terephthalate as a main component, or a polyamide polymer having nylon 6 or nylon 66 as a main component is preferable. Also,
Those obtained by copolymerizing a small amount of the third component with these polymers can also be used. Examples of polyesters include terephthalic acid, isophthalic acid, naphthalene-2,5-dicarboxylic acid, α, β- (4-carboxyphenoxy) ethane, 4,4′-dicarboxydiphenyl, alkylene oxide adduct of bisphenol A, and adipic acid. , Azelaic acid, sebacic acid, ethylene glycol, diethylene glycol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, cyclohexane-1,4-dimethanol, polyethylene glycol,
A fiber-forming polyester polymer synthesized from an aromatic, aliphatic, or alicyclic dicarboxylic acid such as polytetramethylene glycol; a diol; an oxycarboxylic acid such as hydroxybenzoic acid; 80 mol% or more of constitutional units A polyester polymer having 90 mol% or more of ethylene terephthalate units or butylene terephthalate units is particularly preferable. Further, these polymers may contain additives such as an optical brightener and a stabilizer.

In order to improve the dyeability of a fiber product made of fibers containing a large amount of inorganic fine particles and to impart vividness to the color tone to obtain a high-grade color tone, an aromatic group as Component A is used. It is preferable to use a polyester obtained by copolymerizing a bifunctional monomer having a —SO ↓ 3M group (wherein M is a hydrogen atom, a metal atom, or an alkylphosphonium group) bonded to. Even if this difunctional monomer is a dicarboxylic acid (or its derivative) compound,
It may be a diol compound or an oxycarboxylic acid compound.

Examples of the aromatic group to which the —SO ↓ 3M group is bonded include a benzenetriyl group, a naphthalenetriyl group, an anthracentriyl group, a diphenyltriyl group, an oxydiphenyltriyl group, a sulfodiphenyltriyl group,
Examples thereof include a methylenediphenyltriyl group. When M is a metal atom, specific metal atoms include sodium, potassium, magnesium, calcium, copper, iron and the like. When M is an alkylphosphonium group, specific groups include a tetrabutylphosphonium group, an ethyltributylphosphonium group, a benzyltributylphosphonium group, a tetraphenylphosphonium group, a phenyltributylphosphonium group and a benzyltriphenylphosphonium group. Be done.

The copolymerization amount of the above-mentioned bifunctional monomer having a —SO ↓ 3M group is such that when the bifunctional monomer is a dicarboxylic acid (or its derivative) compound, the total amount constituting the polyester is It is preferably 1.0 mol% or more, particularly preferably 1.5 mol% or more based on the carboxylic acid compound. Similarly, when the difunctional monomer is a diol compound, it is based on all the diol compounds constituting the polyester. When the bifunctional monomer is an oxycarboxylic acid compound, 1.0 mol% or more, particularly 1.5 mol%, relative to either one of all dicarboxylic acid compounds and all diol compounds constituting the polyester. % Or more is preferable. When it is less than 1.0 mol%, a clear color tone cannot be sufficiently obtained.

By using a polyester obtained by copolymerizing a bifunctional monomer having a —SO ↓ 3M group as the component A, a vivid and high-quality color tone can be obtained when dyed with a KAOTIN dye. However, -S ↓ 3M
If the copolymerization amount of the group-containing monomer exceeds 5.5 mol%, the physical properties of the fiber, especially the fiber strength will be deteriorated.
It is preferably 5.5 mol% or less. Of course, in the present invention, a method of mixing a polyester having a high copolymerization amount and a polyester having a low copolymerization amount to obtain a predetermined copolymerization amount may be used.

As a method for obtaining the conjugate fiber of the present invention, the component A and the component B are heated and melted in separate melting systems, respectively fed to a spinneret by an ordinary extrusion spinning device, and immediately before the spinneret. It can be obtained by combining the components according to the above-described composite shape and extruding the yarn obtained by winding or once storing it in a can and then further stretching and heat treating. Further, a method of extruding from the spinneret and immediately stretching without winding or accumulating in a can, or a method of extruding from the spinneret and winding at high speed to obtain a product as it is can be used.
Of course, post-processing such as crimping or false twisting can be applied.

The present invention solves a problem that occurs when a fiber having a fineness of 8 denier or less is obtained from a polymer containing a large amount of inorganic fine particles, that is, a deterioration in spinnability. Therefore, when trying to obtain a fiber having a fineness of more than 8 denier, there is no problem to be solved by the present invention. The present invention exerts a very remarkable effect especially when it is intended to obtain fibers having a fineness of 5 denier or less.

The conjugate fiber obtained in the present invention exhibits the effect of the present invention not only in the long fiber but also in the short fiber.
In addition, the composite fiber obtained in the present invention has a fiber cross-section formed into a shape similar to a polygon such as a pentagon or hexagon by a higher-order processing such as false twist crimping, or a modified cross-section nozzle at the time of spinning. It may have a polygonal shape such as a three-lobed shape, a T-shaped, a four-lobed shape, an eight-lobed shape, or any other irregular cross-sectional shape. Further, in the core-sheath structure fibers shown in FIGS. 1 to 6, the component B may have an irregular cross-sectional shape other than the round cross-section. In short, the fibers of the present invention satisfying the requirements described above can achieve the object of the present invention. The present invention exerts a particularly excellent effect when fine particles that absorb or reflect ultraviolet rays are used as the inorganic fine particles. Because, in order to obtain a fiber having a sufficient ultraviolet shielding effect, it is necessary to add a large amount of the fine particles, and in order to use this fiber for clothing,
It is preferable that the fiber has the same thinness as that of a usual fiber for clothing, for example, 3 denier or less, and the fiber of the present invention is very suitable as such a fiber.

The composite fiber of the present invention can be used in a wide variety of applications as a woven fabric, a knitted fabric, a non-woven fabric, etc., alone or in combination with other fibers. When mixed with other fibers, it is possible to use mixed fibers, compound yarns, compound twists, mixed wovens, mixed knits, and all other means, and the obtained fabrics may be dyed, resin-processed, etc., if necessary. It can be processed and provided for various purposes. Of course, it is also possible to dye in the form of fiber, yarn or fiber product.

When the conjugate fiber obtained in the present invention is a fiber which shields ultraviolet rays, suitable applications thereof include staples for clothes, dry non-woven fabrics and wet non-woven fabrics for short fibers, and woven fabrics for long fibers. , Knitting, etc. More specifically, field sportswear such as soccer and golf, T-shirts, polo shirts, marathon, beachwear, swimwear and other outdoor sportswear, hats, blouses, veil, stockings, gloves, hoods, curtain,
Examples thereof include blind slats, parasols, tents, light-shielding materials for agriculture, and dyes thereof.

[0038]

The present invention will be described below with reference to examples. Regarding the ultraviolet ray shielding property in the examples, the samples were evaluated by the following evaluation methods. First, the obtained fiber is 75
A denier multifilament was prepared, and a plain weave was prepared from the multifilament at a weaving density of warp density of 95 filaments / inch and weft density of 60 filaments / inch. The measurement was performed by using an ultraviolet intensity integrator manufactured by Toray Techno Co., Ltd. and measuring the ultraviolet transmittance of the woven fabric. That is, install a measurement sample in the center of the ultraviolet intensity integrator, prepare an ultraviolet intensity integrator that does not have a sample at the same time, irradiate each with ultraviolet light, measure the amount, and use the following formula The transmittance was calculated. Ultraviolet transmittance (%) = 100 X (U / Uo) U = UV amount on sample side Uo = UV amount on no sample side The lower the UV transmittance, the better the shielding performance.

In the examples, the fiberizing processability is
It is indicated by the A rating in the stretching process. The A rating was calculated by the following formula. A rating = 100X (number of bobbins without fluff / thread breakage) / (total number of bobbins) Therefore, the higher the A rating, the better the processability. However, in the above formula, the total number of bobbins is the number of bobbins obtained after two hours of continuous operation for one week, and during winding (that is, less than two hours from the beginning of winding).
If the yarn breakage occurred at that time, the bobbin was switched to a new one at that point and winding was started.

Reference Example A dry, nitrogen-substituted autoclave was used in which cyclohexane was used as a solvent, n-butyllithium was used as a polymerization catalyst, and N, N, N'N'-tetramethylethylenediamine was used as a vinylating agent. A styrene monomer and isoprene were used. A monomer or a butadiene monomer and a styrene monomer were added in this order and polymerized. The obtained triblock copolymer was subjected to hydrogenation reaction in cyclohexane at a hydrogen pressure of 20 kg / cm ↑ 2 using Pd-C as a hydrogenation catalyst to obtain a block copolymer having the molecular characteristics shown in Table 1. Obtained.

Example 1 38 parts by weight of a block copolymer (a) containing 0.3% by weight of a hydroxy-tert-butylphenyl compound represented by the following formula 13 was added to 38 parts by weight of a dioxide having an average particle diameter of 0.4 μm. Strand extruded by adding 60 parts by weight of titanium (manufactured by Titanium Industry Co., Ltd .: UV performance: UV transmittance almost 0) and 2 parts by weight of magnesium stearate and kneading with a biaxial kneader at a temperature of 230 ° C. Was cut to obtain pellets.

[0042]

[Chemical 13]

Component B was obtained by melt-mixing the obtained titanium dioxide-containing block copolymer (a) pellets and the block copolymer (a) pellets containing no titanium dioxide at a weight ratio of 1: 1. Was supplied to the extruder. On the other hand, as the component A, polyethylene terephthalate containing 0.05% by weight of titanium dioxide (intrinsic viscosity [η] = 0.65) was melt extruded by another extruder,
At a spinning temperature of 295 ° C., component A is combined as a sheath component and component B as a core component at a nozzle portion, and a composite weight ratio A: B is 2: 2.
1 and the cross-section as shown in FIG.
It was wound up at 00 m / min. The obtained spun yarn is hot roller 75 ° C. The plate was drawn under the conditions of 140 ° C. and a draw ratio of 3.4 times to obtain a multifilament of 75 denier / 24 filament. When the core polymer constituting the multifilament fiber was extracted with toluene and the molecular weight distribution was checked, it was almost the same as the raw material, which confirmed that the MFR value did not change. When the cross-sectional shape of this multifilament yarn was observed with a microscope, the core-sheath ratio was almost constant in both fibers and in the length direction, and the core component was completely covered by the sheath component, and It was excellent in uniformity and had no fluff.

Using the thus obtained drawn yarn, a plain woven fabric was prepared at a weaving density of warp density of 95 yarns / inch and weft density of 60 yarns / inch and subjected to refining finishing to obtain a measurement sample. In the above manufacturing process, the A rating in the spinning step was 98%, and the A rating in the drawing step was 93%, which was extremely good. Furthermore, the processability in producing the woven fabric and the subsequent processability were both good. When the ultraviolet shielding property was measured, it was found that the ultraviolet shielding property was extremely good.

Comparative Example 1 Fiberizing was performed under the same polymer and under the same conditions as in Example 1 except that the component B did not contain any hydroxy-tert-butylphenyl compound. However, the component B polymer is thermally decomposed in the spin pack, and bubbles are generated in the fiber due to the decomposition gas, and as a result,
Single yarn breakage occurred during spinning, and good spinning base yarn could not be obtained in good yield.

Examples 2 to 8 The same procedure as in Example 1 was carried out except that the conditions shown in Table 2 were changed. The processability was good, the cross-sectional shape and homogeneity of the fiber were good, and the UV shielding property was at a good level.

Examples 9 to 13 In Example 9, polybutylene terephthalate was used as the component A, in Example 10, nylon 6 was used as the component A, and in Example 11, a hydroxy-tertiary butylphenyl compound represented by the following chemical formula 14 was used. Example 12 was used as a hydroxy-tert-butylphenyl compound, and the compound of Example 13 was used as a hydroxy-tert-butylphenyl compound. The same procedure as in Example 1 was carried out except that a drawn yarn of 75 denier / 24 filament was obtained by a method of continuously drawing without winding. When the cross-sectional shape of the obtained multifilament yarn was observed with a microscope, all the fibers had the same core-sheath ratio as those of the multifilament yarn in the same manner as in Example 1, and were extremely excellent in uniformity. There was no fluff.

[0048]

[Chemical 14]

[Chemical 15]

[Chemical 16]

Comparative Example 2 Fibring was carried out under the same conditions as in Example 1 except that titanium dioxide was not added to the component B, and 75
A multifilament of denier / 24 filament was obtained. Then, a plain woven fabric was prepared in the same manner as in Example 1, and the ultraviolet transmittance was examined. The ultraviolet shielding property was at a level considerably lower than that of Example 1. Subsequently, a long-sleeved shirt using the woven fabric of Example 1 and the woven fabric of Comparative Example 2 for each of the left and right halves was produced, and only the long-sleeved shirt was actually worn by five people on the upper half of the body under the sunlight. A 50-hour wearing test was conducted. The results are shown in Table 3.

Further, the woven fabric of Example 1 and the woven fabric of Comparative Example 2 were used to fabricate parasols as umbrella fabrics. When the transmittance of ultraviolet rays of the obtained parasol was examined, the values shown in Table 2 were almost the same. Further, the woven fabric of Example 1 and the woven fabric of Comparative Example 2 were used to produce hats having the same specifications. Compared with the thing of the comparative example 2, the thing of the example 1 had less stuffiness of the head even if it was worn for a long time in direct sunlight, and was comfortable.

Examples 14 to 18 The same procedures as in Example 1 were carried out except that the inorganic fine particles shown in Table 2 were used as the component B. In Example 14, 15% by weight of titanium dioxide having an average particle size of 0.4 μm (UV performance: not transmitted at all) and 15% by weight of zinc oxide having an average particle size of 0.5 μm (UV performance: not transmitted at all). This is an example of addition. Example 15 is an example using 20% by weight of the above zinc oxide, and Example 16 is an example using 15% by weight of the above titanium dioxide and 15% by weight of barium sulfate having an average particle size of 0.5 μm (ultraviolet performance: hardly transmitted). Example 17 is an example using 15% by weight of the above titanium dioxide and 15% by weight of silicon dioxide having an average particle size of 0.1 μm (ultraviolet performance: hardly transmitted), and Example 18 is 0%. This is an example in which 15 wt% of 0.5 μm alumina (ultraviolet ray performance: hardly transmitted) and 15 wt% of the above titanium oxide are used. The results are shown in Table 2.

Examples 19 to 20 In Example 19, the block copolymer (b) was used as the component B polymer, and in Example 20, except that the block copolymer (c) was used as the component B polymer. Spinning and drawing were carried out in the same manner as in 1 to obtain 75 denier / 24 filament multifilaments. When the cross-sectional shape of the obtained multifilament yarn was observed with a microscope, all the fibers in the multifilament yarn had almost the same core-sheath ratio as in Example 1 and were extremely uniform, and the fluff There was no.

Comparative Examples 3 to 4 Comparative Example 3 was the same as Example 1 except that the block copolymer (d) was used as the component B polymer, and Comparative Example 4 was used except that the block copolymer (e) was used as the component B polymer. Spinning was carried out in the same manner. In both cases, the component B polymer was severely decomposed during spinning, and fiberization was impossible.

Example 21 Example 1 was repeated except that polyethylene terephthalate obtained by copolymerizing 5-sodium sulfoisophthalic acid containing 0.05% by weight of titanium dioxide in an amount of 1.7 mol% with respect to all acid components was used as the component A. 75 denier / 24 in the same manner as
A multifilament of filaments was obtained. When the core polymer constituting the multifilament fiber was extracted with toluene and the molecular weight distribution was checked, it was almost the same as the raw material, which confirmed that the MFR value did not change. When the cross-sectional shape of this multifilament yarn was observed with a microscope, the core-sheath ratio was almost constant in both fibers and in the length direction, and the core component was completely covered by the sheath component, and Excellent homogeneity and no fluff.

Using the thus obtained drawn yarn, a plain woven fabric was produced with a weaving density of 95 warps / inch and weft density of 60 yarns / inch, subjected to refining and finishing, and used as a sample for measurement. In the above manufacturing process, the spinnability, the stretchability, the processability in the production of the fabric, and the subsequent processability were all good. When the ultraviolet shielding property was measured, it was found that the ultraviolet shielding property was extremely good. Further, the obtained plain woven fabric was dyed with a chaostin dye under the following conditions. Cathilon Brill Red 4GH 2% owf Na ↓ 2SO ↓ 4 2g / l Acetic acid (glacial acetic acid) 1% owf Sodium acetate 0.5% owf Bath ratio 50: 1 120 ° C x 1 hour Dyeing with disperse dye in Comparative Example 5 described later Compared with the dyed fabric, Comparative Example 5 was inferior in vividness, but Example 19 had vivid and extremely good color development.

Comparative Example 5 A woven fabric was produced under the same conditions as in Example 21 except that polyethylene terephthalate containing 0.05% by weight of titanium dioxide was used as the component A. The plain fabric obtained was dyed with a disperse dye under the following conditions. Sumikaron Red SE-RPD 2% owf dispersant Nikkasan salt # 7000 0.5% / l pH adjuster ammonium sulfate 1 g / l acetic acid (48%) 1 cc / l bath ratio 50: 1 130 ° C. × 1 hour Example 21 and In comparison, the coloring property represented by the sharpness was poor.

Comparative Example 6 Fiberizing was carried out under the same polymer and under the same conditions as in Example 21 except that the component B contained no hydroxy-tert-butylphenyl compound.
However, the component B polymer is thermally decomposed in the spinning pack, and bubbles are generated in the fiber due to the decomposition gas. As a result, single yarn breakage occurs during spinning, and a good spinning raw yarn can be obtained in good yield. I could not do it.

Examples 22 to 28 The same procedure as in Example 21 was carried out except that the conditions shown in Table 5 were changed. The processability was good, the cross-sectional shape and homogeneity of the fiber were good, and the UV shielding property was at a good level. Moreover, the dyed product was also very excellent in sharpness.

Examples 29 to 33 In Example 29, polyethylene terephthalate copolymerized with 2.5 mol% of 5-sodium sulfoisophthalic acid was used as the component A polymer, and in Example 30, 5-sodium sulfoisophthalic acid was used as the component A polymer. 4.5 mol%
Copolymerized polyethylene terephthalate was used, Example 31 uses the compound of the following formula 14 as the hydroxy-tert-butylphenyl compound, and Example 32 uses the hydroxy-tertiary-butylphenyl compound.
The following 15 compounds were used as tert-butylphenyl compounds, and Example 33 was prepared by using the following 16 compounds as hydroxy-tert-butylphenyl compounds, each of which was spun and continuously stretched without winding. The procedure of Example 21 was repeated, except that a drawn yarn of 75 denier / 24 filament was obtained. When the cross-sectional shape of the obtained multifilament yarn was observed with a microscope, all the yarns had the same core-sheath ratio as those of the multifilament yarn in the same manner as in Example 21, and were extremely uniform. There was no fluff. Further, it was also extremely excellent in the sharpness of color after dyeing.

Comparative Example 7 Fiberizing was carried out under the same conditions as in Example 21 except that titanium dioxide was not added to the component B,
A multifilament of 75 denier / 24 filament was obtained. Then, a plain weave fabric was prepared in the same manner as in Example 21, and the ultraviolet ray transmittance was examined. The ultraviolet shielding property was at a level considerably lower than that of Example 21. Further, when dyeing was performed in the same manner as in Example 21, the sharpness was excellent.

Examples 34 to 38 The procedure of Example 21 was repeated, except that the inorganic fine particles shown in Table 5 were used as the component B. In Example 34, 15% by weight of titanium dioxide having an average particle size of 0.4 μm (UV performance: not transmitting at all) and 15% by weight of zinc oxide having an average particle size of 0.5 μm (UV performance: not transmitting at all). This is an example of addition. Example 35 is an example using 20% by weight of the above zinc oxide, and Example 36 is an example using 15% by weight of the above titanium dioxide and 15% by weight of barium sulphate having an average particle size of 0.5 μm (ultraviolet ray performance: not transmitted at all). Example 37 is an example using 15% by weight of the above titanium dioxide and 15% by weight of silicon dioxide having an average particle size of 0.1 μm (ultraviolet ray performance: hardly transmitted), and Example 38 is 0.5 μm. 15% by weight of alumina (UV performance: hardly transmitted) and 15% by weight of the above titanium oxide are used. The results are shown in Table 5.

Comparative Example 8 The procedure of Example 21 was repeated except that the block copolymer (e) was used as the component B polymer, but the component B polymer was severely decomposed during spinning, and fiberization was impossible. ..

[0063]

[Table 1]

[0064]

[Table 2]

[0065]

[Table 3]

[0066]

[Table 4]

[0067]

[Table 5]

[Brief description of drawings]

FIG. 1 is a diagram showing an example of a cross-sectional shape of a conjugate fiber of the present invention.

FIG. 2 is a diagram showing another example of the cross-sectional shape of the conjugate fiber of the present invention.

FIG. 3 is a diagram showing another example of the cross-sectional shape of the conjugate fiber of the present invention.

FIG. 4 is a diagram showing another example of the cross-sectional shape of the conjugate fiber of the present invention.

FIG. 5 is a diagram showing another example of the cross-sectional shape of the conjugate fiber of the present invention.

FIG. 6 is a diagram showing another example of the cross-sectional shape of the conjugate fiber of the present invention.

FIG. 7 is a diagram showing another example of the cross-sectional shape of the conjugate fiber of the present invention.

FIG. 8 is a diagram showing another example of the cross-sectional shape of the conjugate fiber of the present invention.

[Explanation of symbols]

Protective polymer layer component composed of A fiber-forming thermoplastic polymer B block copolymer layer component

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Eiichiro Nakamura 1-1239 Umeda, Kita-ku, Osaka Kuraray Co., Ltd.

Claims (3)

[Claims] 1. A single yarn fineness of 8 comprising a protective polymer layer component (A) made of a fiber-forming thermoplastic polymer and a polymer layer component (B) containing inorganic fine particles.
A fiber in which the component (A) accounts for less than or equal to denier and 60% or more of the fiber cross-sectional perimeter is (I) the amount of the inorganic fine particles in the component (B) is 5 to 85% by weight, and (II)
In the component (B), 0.1% by weight or more of a hydroxy-tert-butylphenyl compound having a hydroxyl group in the ortho position to the butyl group is added to the polymer constituting the component (B). (III) The polymer constituting the component (B) is composed of a polyaromatic vinyl block having a number average molecular weight of 4000 to 50,000 in one block and a number average molecular weight of 10,000 to 1 in one block.
A block copolymer consisting of 50,000 polyconjugated diene blocks, wherein 30% or more of the conjugated diene-based double bonds of the conjugated diene block are hydrogenated.
A composite fiber having a number average molecular weight of 30,000 to 250,000. 2. A bifunctional monomer in which the protective polymer layer component (A) has an aromatically bonded --SO.sup.3M group (where M is a hydrogen atom, a metal atom or an alkylphosphonium group). The composite fiber according to claim 1, wherein the body is a copolymerized polyester. 3. The composite fiber according to claim 1, which is a core-sheath type composite fiber having a sheath of the protective polymer layer component (A) and a core of the polymer layer component (B) containing inorganic fine particles. ..