JP2007056411A - Heat-storage hydrophilic fiber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a heat-storage hydrophilic fiber that has sufficient hydrophilicity derived from a hydroxy group in spite of being a synthetic fiber, stores heat obtained by sunshine, etc., to raise the surface temperature of fiber and has both heat storage property and hydrophilicity. <P>SOLUTION: The heat-storage hydrophilic fiber is a fiber composed of a thermoplastic resin comprising ceramic fine particles having light absorption and heat exchange function and a modified polyvinyl alcohol resin in which the content of the ceramic fine particles having light absorption and heat exchange function is 0.1-20 mass% based on the fiber mass and the content of the modified polyvinyl alcohol resin is 3-40 mass% based on the fiber mass. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a heat storage hydrophilic fiber having a hydrophilic property and a heat storage property, which is a fiber made of a thermoplastic resin containing ceramic fine particles having an absorption heat conversion function and a modified polyvinyl alcohol resin.

  2. Description of the Related Art Conventionally, various fibers have been proposed in the field of clothing, daily life materials, and industrial materials as synthetic fibers with hydrophilic properties such as hygroscopicity and moisture release properties.

  For example, Patent Document 1 proposes a polyamide fiber in which polyvinyl pyrrolidone or polyether ester amide is contained in polyamide to exhibit moisture absorption / release properties (having moisture absorption and moisture release properties). Further, Patent Document 2 proposes a fiber in which a thermoplastic water-absorbing resin composed of a crosslinked product of polyethylene oxide is contained in polyamide or polyester to exhibit moisture absorption and desorption.

  However, since the hygroscopic component contained in these fibers does not have a hydroxyl group, these fibers do not have a hydrophilic or hygroscopic property derived from a hydroxyl group such as natural fibers. Depending on the intended use, water absorption and moisture absorption / release performance may be insufficient.

  On the other hand, Patent Document 3 proposes a fiber that exhibits water absorption and moisture absorption and desorption by blending a modified polyvinyl alcohol resin with a thermoplastic resin. Since this modified polyvinyl alcohol resin has hydroxyl groups like natural fibers, it has been reported that sufficient water absorption and moisture absorption and desorption can be obtained. The use for various uses, such as material use and marine products, is shown.

In the clothing and industrial materials fields, they are often used in cold regions, but when these fibers are used at low temperatures, the physical properties are likely to deteriorate, especially in civil engineering construction materials and fishery materials. There was a problem that it was difficult to maintain. In addition, when used in aquaculture nets such as seaweed among marine materials, higher fiber temperature is preferred for germination and growth of seaweed spores adhering to the fibers, and fibers with excellent heat storage properties are required. It was.
JP-A-7-150414 JP-A-8-260244 JP 2005-120529 A

  The present invention solves the above-mentioned problems, has both hydrophilicity and heat storage properties, is less likely to deteriorate even when used in cold regions, and is suitably used for various uses in clothing and industrial materials In particular, when used for marine materials such as seaweed aquaculture nets such as seaweed, it provides thermal storage hydrophilic fibers that can exert excellent effects on germination and growth of seaweed spores attached to the fibers This is a technical challenge.

  The inventors of the present invention have arrived at the present invention as a result of studies to solve the above problems.

  That is, the present invention is a fiber composed of a thermoplastic resin containing ceramic fine particles having an absorption heat conversion function and a modified polyvinyl alcohol resin, and the content of the ceramic fine particles having an absorption heat conversion function is 0.1 to the fiber mass. The heat-retaining hydrophilic fiber is characterized in that it is ˜20 mass%, and the content of the modified polyvinyl alcohol resin is 3 to 40 mass% with respect to the fiber mass.

  Since the heat storage hydrophilic fiber of the present invention contains a modified polyvinyl alcohol having a hydroxyl group as a water-absorbing substance, it can be a hydrophilic fiber having excellent water absorption performance and improved hydrophilicity. Furthermore, because it contains ceramic fine particles having an absorption heat conversion function, it is possible to store heat obtained by sunlight, etc., to increase the surface temperature of the fiber, and to store heat-storing hydrophilic fibers that combine heat storage and hydrophilicity. It can be. For this reason, it is suitable for various uses such as apparel use such as inner, socks and ski wear, civil engineering construction materials such as ropes, nets and vegetation materials, seaweed cultivation nets such as laver and marine materials such as artificial algae fields. Can be used.

  Hereinafter, the present invention will be described in detail.

  As the thermoplastic resin constituting the fiber of the present invention, polyamide, polyester, polyolefin and the like are preferable.

  Polyamides include polyimino-1-oxotetramethylene (nylon 4), polytetramethylene adipamide (nylon 46), polycoupleramide (nylon 6), polyhexamethylene adipamide (nylon 66), polyundecanamide (nylon) 11), polylaurolactamide (nylon 12), polymetaxylene adipamide, polyparaxylylene decanamide, polybiscyclohexylmethane decanamide and the like. And these copolymers and blends may be sufficient. Of these, nylon 6 is preferable because it is inexpensive and has excellent strength and durability.

  Examples of the polyolefin include aliphatic α-monoolefins having 2 to 18 carbon atoms, such as ethylene, propylene, butene-1, pentene-1,3-methylbutene-1, hexene-1, octene-1, dodecene-1, and octadecene. -1 is a homopolyolefin. Aliphatic α-monoolefins are polyolefins that are copolymerized with other ethylenically unsaturated monomers, for example similar ethylenically unsaturated monomers such as butadiene, isoprene, 1,3-pentadiene, styrene, α-methylstyrene. There may be. In the case of polyethylene, it may be one in which propylene, butene-1, hexene-1, octene-1 or similar higher α-olefin is copolymerized to 10% by mass or less with respect to ethylene. In the case, 10% by mass or less of ethylene or a similar higher α-olefin may be copolymerized with propylene.

  Polyesters include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, naphthalene-2,6-dicarboxylic acid, aliphatic dicarboxylic acids such as adipic acid and sebacic acid, or esters thereof, and ethylene glycol, diethylene glycol. 1, 4-butanediol, neopentyl glycol, cyclohexane-1,4-dimethanol, and the like, and homopolyesters or copolymers or blends thereof. Further, it may be polylactic acid obtained by polymerizing lactic acid mainly composed of D-lactic acid and / or L-lactic acid. These polyesters may be added or copolymerized with paraoxybenzoic acid, 5-sodium sulfoisophthalic acid, polyalkylene glycol, pentaerythritol, bisphenol A, or the like.

  In the present invention, the thermoplastic resin having the above-described fiber-forming property may be various inorganic particles such as titanium oxide, silicon oxide, calcium carbonate, silicon nitride, clay, talc, and the like, if necessary. In addition to particles such as polymer particles and various metal particles, conventionally known antioxidants, antioxidants, anti-coloring agents, light-proofing agents, inclusion compounds, anti-static agents, various coloring agents, various surfactants, various reinforcing agents Various additives such as fibers may be added within a range not impairing the effects of the present invention.

  The fiber of the present invention contains a modified polyvinyl alcohol resin in the thermoplastic resin as described above. Content of modified polyvinyl alcohol is 3-40 mass% with respect to fiber mass, More preferably, it is 5-30 mass%. If it is less than 3% by mass, it does not have sufficient water absorption performance, and it becomes difficult to obtain a hydrophilic fiber. On the other hand, if it exceeds 40% by mass, it is not preferable because the spinning property is deteriorated and the physical properties such as the strength and elongation are likely to be lowered.

  The modified polyvinyl alcohol resin is preferably blended (mixed) in the thermoplastic resin. That is, it is preferable that the modified polyvinyl alcohol resin does not exist as a separate layer in the thermoplastic resin, but the modified polyvinyl alcohol resin is preferably uniformly blended in the thermoplastic resin. It is preferable that the blend is spun into a fiber. Thereby, it can prevent that a modified polyvinyl alcohol resin peels off and elutes from a fiber, and durability of water absorption performance improves.

  Next, the modified polyvinyl alcohol resin contained in the fiber of the present invention is preferably an oxyalkylene group-containing polyvinyl alcohol. Specifically, oxyalkylene group-containing polyvinyl alcohol is a copolymer of vinyl acetate and polyoxyalkylene (meth) allyl ether such as polyoxyethylene (meth) allyl ether, polyoxypropylene (meth) allyl ether, It is then obtained by saponification. In this case, the copolymerization ratio (content) of the polyoxyalkylene (meth) allyl ether is preferably 0.1 to 20 mol%, more preferably 0.1 to 5 mol%. The degree of condensation of the polyoxyalkylene is 1 to 300, preferably 3 to 50, and the proportion of oxyalkylene units in the entire oxyalkylene group-containing polyvinyl alcohol is preferably 3 to 40% by mass. This indicates that there is an optimum range for the degree of localization-delocalization of oxyalkylene units and the length of oxyalkylene units in the copolymer.

  The saponification degree of vinyl acetate units in the oxyalkylene group-containing polyvinyl alcohol is preferably 50 to 100 mol%, more preferably 70 to 99 mol%, and the average polymerization degree of polyvinyl alcohol is preferably 150 to 1500, and more preferably 200 to 1000. In addition, components other than polyoxyalkylene (meth) allyl ether may be contained as a copolymerization component as long as the object of the present invention is not impaired. For example, α-olefin (ethylene, propylene, long chain α-olefin, etc.) , Ethylenically unsaturated carboxylic acid monomers (acrylate, methacrylate, acrylonitrile, methacrylonitrile, vinyl chloride, vinyl ether, etc.) may be contained as long as they are about 30 mol% or less.

  As the polymerization method for obtaining the oxyalkylene group-containing polyvinyl alcohol, a solution polymerization method is usually employed, and in some cases, a suspension polymerization method, an emulsion polymerization method, or the like can also be employed. As the saponification reaction, an alkali saponification method, an acid saponification method or the like is employed.

  In addition to the above, polyvinyl alcohol containing oxyalkylene group includes vinyl acetate, polyoxyethylene (meth) acrylate, polyoxypropylene (meth) acrylate, polyoxyethylene (meth) acrylamide, polyoxypropylene (meth) acrylamide, polyoxyethylene (1- (meth) acrylamide-1,1-dimethylpropyl) ester, polyoxyethylene vinyl ether, polyoxypropylene vinyl ether, polyoxyethylene allylamide, polyoxypropylene allylamide, polyoxyethylene vinylamide, polyoxypropylene vinylamide Etc. can be obtained by copolymerization and then saponification.

  In addition, the oxyalkylene group-containing polyvinyl alcohol can also be obtained by reaction of alkylene oxide with polyvinyl alcohol, or polymerization of vinyl acetate with polyoxyalkylene glycol and subsequent saponification.

  The oxyalkylene group-containing polyvinyl alcohol thus obtained is further one of (1) a phenol compound having a melting point of 50 to 250 ° C., (2) a thioether compound, and (3) a phosphite compound. The above is preferably added in an amount of 0.01 to 5.0 mass%, particularly 0.1 to 0.5 mass% with respect to the oxyalkylene group-containing polyvinyl alcohol. Thereby, thermal stability can be improved. If the amount added is less than 0.01% by mass, improvement in thermal stability cannot be expected, and if it exceeds 5.0% by mass, the hydrophilicity tends to decrease.

  (1) Phenol compounds having a melting point of 50 to 250 ° C. include 2,5-di-t-butylhydroquinone, 2,6-di-t-butyl-p-cresol, 4,4′-thiobis- (6 -T-butylphenol), 2,2'-methylene-bis (4-methyl-6-t-butylphenol), tetrakis- [methylene-3- (3 ', 5'-di-t-butyl-4'-hydroxy Phenylpropionate] methane, octadecyl-3- (3 ′, 5′-di-tert-butyl-4′-hydroxyphenyl) propionate, 4,4′-thiobis- (6-tert-butylphenol), N, N ′ Hexamethylene-bis (3,5-di-t-butyl-4'-hydroxy-hydrocinnamamide), 1,3,5-trimethyl-2,4,6-tris (3,5-di-t -Butyl-4-hydro Cibenzyl) benzene, pentaerythryl-tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 1,1,3-tris (2-methyl-4-hydroxy-5-t) -Butylphenyl) butane and the like.

  (2) As thioether compounds, pentaerythritol-tetrakis- (β-laurylthiopropionate), tetrakis [methylene-3- (dodecylthio) propionate] methane, bis [2-methyl-4- {3-n- Alkylthiopropionyloxy} -5-t-butylphenyl] sulfide and the like.

  (3) Phosphite compounds include triphenyl phosphite, tris (p-nonylphenyl) phosphite, tris (2,4-di-t-butylphenyl) phosphite, diphenylisooctyl phosphite, diphenylisodecyl Phosphite, phenyl diisooctyl phosphite, phenyl diisodecyl phosphite, triisooctyl phosphite, tristearyl phosphite, other tetrakis (2,4-di-t-butylphenyl) -4,4'-biphenylenephosphonite And di (2,4-di-t-butylphenyl) pentaerythritol diphosphite.

  Furthermore, in the oxyalkylene group-containing polyvinyl alcohol in the present invention, (4) at least one of a fatty acid having 10 or more carbon atoms or a salt thereof, a fatty acid amide compound, or a fatty acid ester compound is added to the oxyalkylene group-containing polyvinyl alcohol. On the other hand, it is preferably added in an amount of 0.01 to 3.0% by mass, more preferably 0.1 to 0.5% by mass, which further improves the thermal stability.

  (4) Fatty acids having 10 or more carbon atoms or salts thereof are higher fatty acids such as lauric acid, palmitic acid, stearic acid, oleic acid, ricinoleic acid, arachidinic acid, behenic acid, erucic acid, hydroxystearic acid, hydroxyricinol Examples thereof include hydroxy fatty acids such as acids, and metal salts such as magnesium, calcium, strontium, barium, and zinc, among which stearic acid, magnesium stearate, calcium stearate, and magnesium behenate are practical. The fatty acid amide compound (4) is a fatty acid amide such as stearic acid amide, palmitic acid amide, oleic acid amide, behenic acid amide, erucic acid amide, methylene bis stearic acid amide, ethylene bis stearic acid amide or the like. An alkylene bis fatty acid amide is mentioned. Furthermore, fatty acid ester compounds include fatty acid esters of monohydric alcohols such as butyl stearate and butyl palmitate, and fatty acid esters of polyhydric alcohols such as ethylene glycol monostearate.

  As a method of adding the compounds (1) to (4) to the oxyalkylene group-containing polyvinyl alcohol, a conventional method, that is, a melt can with a stirrer, an extruder, a roll kneader, etc. is melt-mixed and pelletized. It is preferable to do. The melt mixing temperature is preferably 160 to 250 ° C, more preferably 180 to 230 ° C.

  As described above, when adding and mixing the modified polyvinyl alcohol resin into the thermoplastic resin, after preparing pellets containing various components in the modified polyvinyl alcohol, adding the mixture into the thermoplastic resin, and melt mixing However, the components (1) to (4) may not be pellets previously melt-blended in modified polyvinyl alcohol, modified polyvinyl alcohol resin, (1) to (4) components, thermoplasticity Each resin may be added and directly melt mixed.

  In addition, other polymers can be blended in the modified polyvinyl alcohol resin as long as the effects of the invention are not impaired, and various additives such as plasticizers, fillers, colorants, and stabilizers are blended. You can also

  Furthermore, the fiber of this invention contains the ceramic microparticles | fine-particles which have an absorption heat conversion function in the above thermoplastic resins.

  The light absorption heat conversion function refers to a function of absorbing light such as sunlight and electric light and converting it into heat energy. Examples of ceramics having such an absorption heat conversion function include carbides of group IV transition metals such as titanium, zirconium and hafnium, carbides such as silicon, boron and tantalum, titanium, silicon, chromium and zirconium. And oxides such as iron and copper, crystals such as mica and calcite, and carbon black. Particularly preferred is a carbide of a transition metal of Group IV of the periodic table having a high absorption heat conversion function.

  These ceramic fine particles having an absorption heat conversion function are preferably fine particles having a particle size of 10 μm or less, particularly 1 μm or less. If the particles are too large, problems such as clogging of the filter medium in the spinning process and a decrease in spinnability due to yarn breakage occur when it is contained in the fiber. Further, even if spinning can be performed, yarn breakage is likely to occur in the drawing process.

  The content of the ceramic fine particles having an absorption heat conversion function is 0.1 to 20% by mass, more preferably 1 to 10% by mass with respect to the fiber mass. If it is less than 0.1% by mass, the intended heat storage and heat retaining property cannot be obtained, and if it exceeds 20% by mass, the operability is deteriorated and the strength of the resulting fiber tends to be lowered.

  As a method of incorporating ceramic fine particles having an absorption heat conversion function into a thermoplastic resin, a method in which ceramic fine particles and a thermoplastic resin are directly mixed and melt-spun at the time of spinning, a thermoplastic resin and an absorption heat conversion function in advance are provided. There is a method of melt spinning ceramic fine particles mixed with a kneader such as a kneader or a mixer.

  The fiber of the present invention may be a single type composed of only one type of thermoplastic resin containing ceramic fine particles having an absorption heat conversion function and a modified polyvinyl alcohol resin, or two or more types of thermoplastic resins. A composite type resin may be used.

  When the fiber of the present invention is a composite fiber (composite fiber), examples of the composite shape include those of a bonded type such as a core-sheath type and a side-by-side type, and a shape of a sea-island type. Of these, a core-sheath type composite fiber is preferable.

  Even when the fiber of the present invention is a composite fiber as described above, the content of the modified polyvinyl alcohol is 3 to 40% by mass with respect to the fiber mass, and the content of the ceramic fine particles having a light absorption heat conversion function is the fiber mass. The content is 0.1 to 20% by mass.

  When making the fiber of this invention into a core-sheath type composite fiber, it is preferable that the modified polyvinyl alcohol resin is contained in the thermoplastic resin which comprises a sheath part at least. That is, in order to impart hydrophilicity such as water absorption to the fiber, it is more effective that the modified polyvinyl alcohol resin is present on the surface of the fiber.

  When the fiber of the present invention is a core-sheath type composite fiber, it is preferable that at least the core contains ceramic fine particles having an absorption heat conversion function. That is, when ceramic fine particles having an absorption heat conversion function are contained in the core, the heat storage effect is enhanced because the core is heated from the inside by the converted thermal energy.

  Furthermore, when the fiber of the present invention is a core / sheath type composite fiber, the core / sheath composite ratio (mass ratio) is set to 80/20 to 20/80, particularly 40/60 to 60/40. Is preferred. When the core / sheath composite ratio is out of the above range, it is not preferable because the yarn-making property is inferior or the physical properties such as the strength and elongation are likely to be lowered.

  The fiber of the present invention may be either a multifilament or a monofilament, and the cross-sectional shape of the single fiber constituting the fiber may be any, for example, a circle, an ellipse, a triangle, a multileaf shape, a square, a rectangle, a rhombus, a saddle type , Horseshoe type and the like can be mentioned, and these shapes may be partially changed. These various cross-sectional fibers can be used in appropriate combination.

  When the fiber of the present invention is a multifilament, the fineness of the single yarn constituting the multifilament is preferably 3.3 to 22 dtex, and the total fineness of the multifilament is preferably 55 to 2200 dtex.

  When the fiber of the present invention is a monofilament, the monofilament fineness of the monofilament is preferably 55 to 1100 dtex, more preferably 220 to 670 dtex from the viewpoints of bundling property, durability, weaving property, etc. It is preferable that

  Next, the manufacturing method of the fiber of this invention is demonstrated using an example.

  When the core-sheath type composite fiber is used as the fiber of the present invention, a conventional composite spinning apparatus is prepared by using a thermoplastic resin containing a modified polyvinyl alcohol resin and a thermoplastic resin containing ceramic fine particles having a function of absorbing heat. Use melt spinning.

  In the case of a multifilament, first, melt spinning is performed from a spinning device, the spun yarn is cooled by a cooling device, a spinning oil is applied, and the undrawn yarn is taken up by a take-up roller. The temperature and air volume of the cooling air, the speed of the take-up roller, etc. are not particularly limited and are appropriately selected. A two-step method in which the unstretched yarn is once wound and then stretched, a method of obtaining a highly oriented unstretched yarn by winding at a high speed without stretching the yarn, and a direct spinning stretch method in which the yarn is continuously stretched without being scraped. To obtain the desired fiber. When extending | stretching, multistage extending | stretching of 1 step | paragraph or 2 steps | paragraphs or more is performed. A stretching method, a stretching temperature, a stretching ratio, and the like are appropriately selected in consideration of the type of polymer constituting the fiber, desired strength and elongation characteristics, and the like. The stretched yarn is wound after being subjected to heat treatment or relaxation treatment as necessary.

  In the case of a monofilament, melt spinning is performed from a spinning device, the spun monofilament is cooled with a liquid or the like, and then the cooled and solidified monofilament is once wound or stretched without being wound. Stretching is performed by one or two or more stages, and after stretching, a relaxation heat treatment is performed in a gas and the film is wound.

Hereinafter, the present invention will be described specifically by way of examples. Various characteristic values in the examples were measured and evaluated as follows.
A. Relative viscosity of polyamide:
Measurement was performed at a concentration of 1 g / dl and a temperature of 25 ° C. using 96% sulfuric acid as a solvent.
B. Polyester relative viscosity:
The measurement was carried out by a conventional method under the conditions of a concentration of 0.5 g / 100 cc and a temperature of 20 ° C. using an equal mass mixed solution of phenol and tetrachloroethane as a solvent.
C. Water absorption (cm):
Using a 33 "28G circular knitting machine (LPJ-H type, manufactured by Fukuhara Seiki Co., Ltd.), the obtained fiber was knitted into a woven fabric having a basis weight of 150 g / m ² with an interlock structure. After adjusting the humidity for 2 hours under the conditions of 60 ° C. and relative humidity, the water uptake height after 10 minutes was measured according to the birec method described in JIS L-1907 (Textile Absorption Test Method). .
D. Thermal storage heat retention:
The resulting plain fabric (weft density 113 / 2.54cm, warp density 77 / 2.54cm) and PET fiber (84dtex / 36f) plain fabric (weft density 113 / 2.54cm, warp density 77 / 2.54) cm) on a metal plate, warmed from room temperature, held at 60 ° C for 30 minutes, naturally cooled, held at 15 ° C, irradiated with a 100W white light source for photography, and infrared image of the surface temperature of the fabric Observation was made with a device (JEOL Thermoview JTG-IB / IBT type), and the surface temperature difference between the two fabrics was measured.

Reference example <Method for producing modified polyvinyl alcohol resin>
After polyoxyethylene (meth) allyl ether having an average degree of condensation of oxyalkylene of 20 and vinyl acetate are copolymerized in methanol in the presence of azobisisobutyronitrile, and then the residual monomer is driven out, sodium hydroxide is added. Was saponified by adding a methanol solution. The copolymer is separated from the slurry produced by the saponification reaction, washed with methanol three times, and then added with 1.5 mol of acetic acid per mol of sodium acetate, and then washed again with methanol twice. The sodium acetate content was adjusted to 0.07% by mass and 0.026% by mass acetic acid (0.5 mol with respect to 1 mol of sodium acetate), and then dried to obtain an oxyalkylene group-containing polyvinyl alcohol resin (hereinafter referred to as “polyvinyl alcohol resin”). Abbreviated as EO-PVA).
The average degree of polymerization of this polymer is 270, the copolymerization ratio of the polyoxyethylene (meth) allyl ether unit is 1.0 mol%, the ratio of the oxyalkylene unit in the whole polymer is 16.1% by mass, the vinyl acetate component The degree of conversion was 96 mol%, the sodium acetate content was 0.07 mass%, and the acetic acid content was 0.026 mass%.
0.3 mass% of pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] having a melting point of 120 ° C. is added to the EO-PVA obtained above as a phenol compound. Then, it was supplied to a twin screw extruder equipped with a round die and extruded at a temperature of 210 ° C. to obtain a pellet-like modified polyvinyl alcohol resin.

Example 1
The modified polyvinyl alcohol obtained in the above reference example is added to a nylon 6 chip having a relative viscosity of 2.6 so that the content is 5% by mass of the whole fiber, and is uniformly melt-mixed. Zirconium carbide fine particles (ZrC) having a particle size of 0.7 μm were used as the ceramic fine particles having a particle size, and the mixture was uniformly melt-mixed so that the content was 5% by mass of the entire fiber to obtain a mixed composition. This mixed composition was continuously supplied to a single-screw extruder, melted at 245 ° C., and melt spinning was performed at a spinning temperature of 260 ° C. using a melt spinning apparatus on which a spinneret having 24 spinning holes was placed. went. The spinning yarn is cooled by blowing air at 15 ° C. from a cooling device, and an oil agent is applied. Then, the yarn is wound at a speed of 4000 m / min, the fineness is 78 dtex, the number of filaments is 24, and the multifilament having a round cross section (high Oriented undrawn yarn) was obtained.

Examples 2-3 and Comparative Examples 1-4
A multifilament was obtained in the same manner as in Example 1 except that the addition amounts of the modified polyvinyl alcohol and the zirconium carbide fine particles were changed and various changes were made so that the content in the fibers became the values shown in Table 1.

Example 4
A multifilament was prepared in the same manner as in Example 1 except that iron oxide (Fe ₂ O ₃ ) was used as the ceramic fine particles having the function of absorbing heat and converted, and the content in the fibers was as shown in Table 1. Obtained.

Example 5
Add the modified polyvinyl alcohol obtained in the above reference example to a nylon 6 chip having a relative viscosity of 2.6 so that the content is 10% by mass of the whole fiber, and melt and mix uniformly to obtain a hydrophilic resin composition. Obtained. Similarly, a nylon 6 chip having a relative viscosity of 2.6 is uniformly melt-mixed with zirconium carbide fine particles (ZrC) having a particle diameter of 0.7 μm so that the content becomes 3% by mass of the entire fiber. A mixed composition was obtained. Using this hydrophilic resin composition as the sheath component and the ceramic mixed composition as the core component, melt spinning was carried out using an ordinary composite spinning apparatus so that the mass ratio of the core component to the sheath component was 1: 1. . At this time, a melt spinning apparatus was used in which the spinning temperature was 260 ° C. and a spinneret having 24 spinning holes was placed. The spinning yarn was cooled by blowing air at 15 ° C. with a cooling device, and an oil agent was applied. Then, the yarn was wound at a speed of 4000 m / min, the fineness was 78 dtex, the number of filaments was 24, and the multifilament having a round cross section ( A highly oriented undrawn yarn) was obtained.

Example 6
Using PET having a relative viscosity of 1.41, the modified polyvinyl alcohol obtained in the above reference example was added so that the content was 20% by mass of the whole fiber, and was uniformly melt-mixed. Zirconium carbide fine particles (ZrC) were uniformly melt-mixed so that the content was 5% by mass of the entire fiber to obtain a mixed composition. This mixed composition was continuously supplied to a single-screw extruder, and melt spinning was carried out at a spinning temperature of 290 ° C. using a melt spinning apparatus equipped with a spinneret having 36 spinning holes. The spinning yarn is cooled by blowing air at 15 ° C. with a cooling device, and an oil agent is applied. Then, the spinning yarn is taken up by a take-up roller having a temperature of 90 ° C. at a speed of 1400 m / min, and subsequently applied to a final drawing roller having a temperature of 130 ° C. The yarn was wound 3.0 times and wound at a speed of 4200 m / min, and a multifilament (highly oriented undrawn yarn) having a round cross section with a fineness of 84 dtex and a filament count of 36 was obtained.

Comparative Example 5
A multifilament was obtained in the same manner as in Example 6 except that zirconium carbide fine particles (ZrC) were not added to PET having a relative viscosity of 1.41.

As is apparent from Table 1, the fibers of Examples 1 to 6 were able to be obtained with good operability, and both water absorption (hydrophilicity) and heat storage and heat retention were excellent.
On the other hand, since the fiber of Comparative Example 1 has a low content of modified polyvinyl alcohol, the water absorption is low and the hydrophilicity is not sufficient. Further, since the fiber of Comparative Example 2 contained too much modified polyvinyl alcohol, yarn breakage occurred frequently during spinning and drawing, and the fiber could not be collected. Moreover, since the fibers of Comparative Examples 3 and 5 did not contain ceramic fine particles, they were inferior in heat storage and heat retention. Since the fiber of Comparative Example 4 contained too much ceramic fine particles, yarn breakage occurred frequently during spinning and drawing, and the fiber could not be collected.

Claims (2)

  A fiber comprising a ceramic fine particle having an absorption heat conversion function and a thermoplastic resin containing a modified polyvinyl alcohol resin, wherein the content of the ceramic fine particle having an absorption heat conversion function is 0.1 to 20% by mass with respect to the fiber mass. The heat storage hydrophilic fiber, wherein the content of the modified polyvinyl alcohol resin is 3 to 40% by mass with respect to the fiber mass. The heat storage hydrophilic fiber according to claim 1, wherein the fiber made of a thermoplastic resin containing ceramic fine particles having an absorption heat conversion function and a modified polyvinyl alcohol resin is a core-sheath type composite fiber.