JP2003027337A - Conjugate fiber having heat-storing and heat-retaining property - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a conjugate fiber excellent in heat-storing and heat- retaining properties and having good dyeing property. SOLUTION: This conjugate fiber is a core-sheath type conjugate fiber in which a conjugate weight ratio of a core component to a sheath component is (10/90) to (50/50). The core part is composed of a polyester-based polymer in which titanium oxide surface-coated with tin oxide is contained in an amount of 4-20 wt.% based on the weight of the core component. The sheath part is composed of a readily dyeable polyester-based polymer in which an aromatic dicarboxylic acid component containing a sulfonate group in polyethylene terephthalate is contained in an amount of 1.0-5.0 mol% and adipic acid and/or polyethylene glycol having <=2,000 molecular weight is contained in an amount of 0.5-8.0 wt.%.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has a heat storage and heat insulation performance suitable for use in clothing and the like, which requires heat insulation.
The present invention relates to a polyester composite fiber which has easy dyeability and good coloring property at the time of dyeing. BACKGROUND OF THE INVENTION [0002] Zirconium carbide fine particles and the like are blended as fibers suitable for cold weather garments that require heat retention and sports garments in the field, especially for swimwear and leisure garments, thereby reducing solar heat. Absorbing heat storage and heat retaining fibers have been developed (Japanese Patent Publication No. 3-9202). This fiber is a core-sheath composite fiber, and zirconium carbide fine particles and the like are blended in the core. However, since the color of the zirconium carbide fine particles and the like disposed on the core is colored on the fiber surface, it is difficult to use the conjugate fiber in applications where the color tone of the fabric is important. To solve this problem, Japanese Patent Laid-Open Publication No.
JP-A-5-51312 discloses zirconium carbide fine particles,
A heat- and heat-retaining fiber having a core-sheath structure using a thermoplastic polymer containing titanium oxide fine particles whose surface is coated with antimony oxide or the like has been proposed. This composite fiber, by using a combination of zirconium carbide fine particles and titanium oxide fine particles surface-coated with tin oxide and antimony oxide, even if the amount of zirconium carbide fine particles is reduced, without lowering the heat storage heat retention. In addition, since the zirconium carbide fine particles are blended in the core, the coloring of the zirconium carbide is concealed by the sheath component, and whiteness can be improved. However, there was a problem that the coloring property at the time of dyeing was not sufficient even with this fiber. JP-A-2-269808 discloses that the core polymer contains fine particles of zirconium carbide and the sheath polymer is a fiber having a core-sheath structure not containing these particles. One in which a number of independent air bubbles are formed in a core portion has been proposed. In this fiber, incident light is irregularly reflected by a large number of independent bubbles in the core, and whiteness is improved. However, since the closed cells of this fiber are formed in the core portion, and one independent bubble is small, incident light is not sufficiently diffusely reflected, and this fiber also has insufficient coloring properties. SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems and provides a fabric which is excellent not only in whiteness but also in coloration at the time of dyeing while being excellent in heat storage and heat retention. It is an object of the present invention to provide a composite fiber that can be used. Means for Solving the Problems The inventors of the present invention have accomplished the present invention as a result of intensive studies for solving the above problems. That is, the present invention relates to a core / sheath composite fiber having a core / sheath composite ratio of 10/90 to 50/50 in mass ratio, wherein the core portion is made of titanium oxide surface-coated with tin oxide. The sheath portion is made of polyethylene terephthalate containing an aromatic dicarboxylic acid component containing a sulfonate group in an amount of 1.0 to 20% by mass.
5.0 mol%, and adipic acid and / or molecular weight 200
A heat storage and heat insulating conjugate fiber comprising a readily dyeable polyester polymer containing 0.5 to 8.0% by mass of polyethylene glycol of 0 or less. Hereinafter, the present invention will be described in detail. The polymer used for the core portion of the core-sheath conjugate fiber of the present invention is formed from a polyester-based polymer having a fiber-forming property. Examples of the polyester-based polymer having a fiber-forming property include aromatic polyester-based polymers. Polymers and aliphatic polyester-based polymers can be used. Examples of the aromatic polyester polymer include, for example, terephthalic acid, isophthalic acid, naphthalene-2,
An aromatic dicarboxylic acid such as 6-dicarboxylic acid or an ester thereof is used as an acid component, and a diol compound such as ethylene glycol, diethylene glycol, 1,4-butanediol, neopentyl glycol, cyclohexane-1,4-dimethanol is used. A homopolyester polymer or a polyester co-condensation polymer as a glycol component can be used. In addition, paraoxybenzoic acid, 5-sodium sulfoisophthalic acid, polyalkylene glycol, pentaerythritol, bisphenol A, and the like may be added or copolymerized to these aromatic polyester polymers. The polyester polymer constituting the core of the core-sheath conjugate fiber of the present invention contains fine particles of titanium oxide surface-coated with tin oxide in an amount of 4 to 20 parts by mass based on the mass of the core component.
% By mass to impart heat storage and heat retaining performance to the resulting fabric. If the content of the titanium oxide fine particles surface-coated with tin oxide is less than 4% by mass, sufficient heat retention property cannot be provided. On the other hand, when the content exceeds 20% by mass, the effect of heat storage and heat retention is saturated, spinnability is deteriorated, fiber strength is reduced, and when processed into a fabric, lightness is poor. . The fine particles of titanium oxide whose surface is coated with tin oxide used in the present invention preferably have an average particle size of 5 μm or less, more preferably 1 μm or less. If the average particle size exceeds 5 μm, clogging of the filter medium easily occurs in the melt spinning step, yarn breakage and the like easily occur, and productivity is impaired, which is not preferable. The polyester polymer used for the core is generally made of polyethylene terephthalate, whose main repeating unit is polyethylene terephthalate. Titanium oxide whose surface is coated with tin oxide is uniformly mixed with polyethylene terephthalate. Alternatively, a polymer mixed at a high concentration with a polyethylene terephthalate polymer may be used as a master chip, mixed with a base polymer and mixed at a predetermined ratio. Next, the polymer forming the sheath portion of the core-sheath conjugate fiber of the present invention contains polyethylene terephthalate as a main repeating unit and contains 1.0 to 5.0 mol% of an aromatic dicarboxylic acid component containing a sulfonate group. ing. Examples of the sulfonate group include 5-sodium sulfoisophthalic acid. The aromatic dicarboxylic acid component containing a sulfonic acid group has a dyeing site that reacts with a cationic dye to form a color, and as this content increases, a larger amount of the dye is fixed in the fiber and expresses good color developability. Things. When the content of the aromatic dicarboxylic acid component containing a sulfonate group is less than 1.0 mol%, the dyeability is impaired. On the other hand, when the content exceeds 5.0 mol%, the spinnability is increased due to excessive acid components. Problems arise, such as hindrance or loss of fiber strength. Further, the polymer forming the sheath portion is a material in which polyethylene terephthalate contains adipic acid, polyethylene glycol (PEG) having a molecular weight of 2000 or less, or both, when used alone or in combination.
0.5 to 8.0 mass%. Adipic acid or PEG increases the amount of dye adsorbed in the fiber by increasing the bulk of the polyester polymer and increasing the diffusivity of the dye, and can further improve the color developability. ,
It exerts its effect at the time of dyeing at normal pressure, and can obtain the same color development as that of normal pressure dyeing. If the content is less than 0.5% by mass, the dyeability is impaired, while if it exceeds 8.0% by mass, the spinnability is impaired or the fiber strength is impaired. PEG must have a molecular weight of 2000 or less. If the molecular weight exceeds 2,000, it is not preferable because it is not completely copolymerized with the polyester but is free in the polymer and has a poor dye diffusion effect. The molecular weight is
More preferably, it is 400 or more. If the molecular weight is less than 400, the melt viscosity of the entire polyester is lowered, and the fiber strength is impaired, and the heat resistance of the fiber is impaired. The polyester polymer forming the core and the sheath may contain a matting agent, a pigment, a flame retardant, a deodorant, a light stabilizer, a heat stabilizer, an antioxidant, if necessary. Various additives such as an agent and a crystallization accelerator may be added within a range that does not impair the purpose of the present invention. The composite ratio (core / sheath) of the core / sheath portion of the core / sheath composite fiber of the present invention is from 10/90 to 50/50 by mass. If the ratio of the polymer in the core is less than this range, the amount of the polyester polymer required to contain the absolute amount of titanium oxide is insufficient, so that sufficient heat storage and heat retention cannot be obtained. On the other hand, if the ratio of the polymer in the core portion exceeds this range, the heat storage and heat retaining property is sufficiently maintained, but the amount of titanium oxide is large, and the clogging of the filter medium and the occurrence of thread breakage during melt spinning occur. , Productivity is impaired. With such a core-sheath composite ratio, the content of titanium fine particles is adjusted so that the titanium oxide covered with tin oxide is uniformly and densely dispersed in the core component. It can be appropriately selected within the range. In particular, composite fibers having a core ratio close to 50% by mass
It has a high heat retention effect and is a material suitable for winter clothing and the like. The conjugate fiber of the present invention can be produced using a conjugate spinning apparatus according to a conventional method for producing a conjugate fiber,
After spinning at a take-up speed of 4500 m / min or less, it can be obtained by stretching. If the take-up speed exceeds 4500 m / min, yarn breakage tends to occur during spinning, and since the draw ratio is low, the strength after drawing is low, and fibers having practical physical properties cannot be obtained. In addition, in order to manufacture with good productivity, the take-off speed is preferably set to 1000 m / min or more. In the stretching, the spun fiber may be once wound up and then supplied to a stretching machine, or, after the spinning, may be directly stretched via a stretching roller and then wound up. The single fiber fineness of the conjugate fiber of the present invention is not particularly limited, but is 1.5 to 8 in the field of clothing.
A range of decitex is preferable, and a range of 2 to 5 decitex is particularly preferable. If the single yarn fineness is less than 1.5 decitex, the fibers are too thin, and the spinning properties in the composite melt spinning method are reduced. If the single-fiber fineness exceeds 8 decitex, the fibers become too thick, and the flexibility of the fibers is impaired, or depending on the content of titanium oxide as a metal component, the fibers become undesirably heavy. However, when the conjugate fiber of the present invention is used for purposes other than apparel, for example, as a sheet for multi-cultivation of plants or a tent base material such as a heat insulating material for various houses, a thick fineness yarn of 8 decitex or more may be used. In a general method for producing long fibers, a spinneret having 10 to 200 holes as spinning holes is used, and the fineness of the long fiber bundle is determined by the above-described single fiber fineness, the number of fibers, and the like. Needless to say, it is determined by Further, the cross-sectional shape of the conjugate fiber of the present invention is not particularly limited. In addition to a normal circular cross-section, a polygonal cross-sectional shape such as a triangular cross-sectional shape, or a portion of the outermost periphery of the cross-section is a protrusion. May have an irregular cross-sectional shape such as The present invention will be described below in detail with reference to examples. The measuring methods of each property used in the examples are as follows. (1) Heat storage heat retention property: Using the obtained fiber as warp and weft, weaving a plain woven fabric with a warp density of 113 threads / 2.54 cm and a weft density of 77 threads / 2.54 cm, in a constant temperature room at 20 ° C and 65% RH. 1.5m
Irradiate light from a 500W white light bulb from a distance of
After a minute, the surface temperature on the opposite side is measured by JEOL infrared sensor:
It was measured by a thermoviewer. Those having a temperature of 26 ° C or more were judged to be excellent in heat storage and heat retention. (2) Relative viscosity: 0.5 g of a sample was dissolved in 100 cc of the solvent using an equal weight mixture of phenol and ethane tetrachloride as a solvent.
The measurement was performed at a temperature of 20 ° C. by a conventional method. (3) Dyeability: A woven fabric was obtained in the same manner as in (1), and the woven fabric was dyed under the following dyeing conditions, and the dyeability was visually evaluated in four steps as shown below. (Dyeing conditions) Cationic dye: Diacryl Black RTL-PF 5% owf Auxiliary agent: CH3C00H (48%) 0.3 cc / L Dyeing time: 100 ° C 30 minutes (Evaluation) ◎ Very good ○ Good △ Normal × Not good [0025] Example 1 A polyethylene terephthalate polymer having a phase viscosity of 1.385 was used as a core component polyester, and titanium oxide fine particles having a particle diameter of 1 μm and surface-coated with tin oxide were contained in an amount of 6% by mass based on the mass of the core component. 2.4 mol% of aromatic dicarboxylic acid component (5-sodium sulfoisophthalic acid) containing sulfonic acid group in polyethylene terephthalate, which is the same as the core component, and 3.8 mass% of adipic acid are copolymerized in the sheath component. A polyester copolymer having a viscosity adjusted to 1.301 was used. Spinning was performed with a core / sheath ratio of 15/85 by mass and a melting temperature of 290 ° C. using a core / sheath composite spinneret. An oil agent is applied to the spun yarn via an oiling roll,
The fiber was pulled by a roller having a surface speed of 1300 m / min. Subsequently, the fiber was wound up by a winding machine having a winding speed of 3800 m / min through a drawing roller, to obtain a long fiber bundle of 56 decitex 24 filaments. Table 1 shows the characteristic values of the obtained core-sheath conjugate fiber and the fabric obtained from the core-sheath conjugate fiber. Examples 2 to 7, Comparative Examples 1 to 9 Composite ratio of core-sheath ratio, amount of titanium oxide, aromatic dicarboxylic acid component containing sulfonate group, adipic acid, PEG
A conjugate fiber was obtained in the same manner as in Example 1 except that the amount of was changed as shown in Tables 1 and 2. Tables 1 and 2 show the characteristic values of the obtained conjugate fiber and fabric. [Table 1] [Table 2] The composite fibers of Examples 1 to 7 have a heat storage property and a heat retention property by solar heat and light rays, and have excellent whiteness due to the presence of titanium oxide whose surface is coated with tin oxide on the core. Furthermore, since the polymer forming the sheath is mainly composed of polyethylene terephthalate and contains sulfonic acid and adipic acid or PEG, it is a composite fiber showing excellent dyeing properties, and is a winter clothing that requires heat storage and heat retention, A useful cloth was obtained in sports clothing in the outdoors, especially in swimwear, leisure and the like. On the other hand, the fiber of Comparative Example 1 was a fiber composed of a single component made of polyethylene terephthalate, and did not not only achieve the heat storage and heat retention intended for the present invention, but also had poor dyeability. The core-sheath conjugate fiber of Comparative Example 2 has poor heat storage and heat retention due to an insufficient amount of titanium oxide, whereas the conjugate fiber of Comparative Example 3 has too much yarn breakage during spinning because the amount of titanium oxide is too large. Occurred and no fibers could be obtained. The fibers of Comparative Examples 4 and 5 each lacked the content of the aromatic dicarboxylic acid component containing a sulfonate group and the content of adipic acid, and the obtained fabrics could not obtain good dyeability. In Comparative Examples 6 and 7, since the content of the aromatic dicarboxylic acid component containing a sulfonate group, adipic acid or PEG was too large, the fiber strength was remarkably reduced, and the number of thread breaks was increased. I couldn't get it.
In the fiber of Comparative Example 8, the ratio of the core component was too low, so that the heat storage / insulation property was insufficient, and the dyeability was also insufficient, because the molecular weight of PEG was too high. In Comparative Example 9, since the ratio of the core component was too high, thread breakage occurred frequently and could not be collected. The core-sheath composite fiber of the present invention is excellent in heat storage and heat retention and whiteness because titanium oxide fine particles surface-coated with tin oxide are blended in the core. In addition, since the polyester polymer forming the sheath uses a polyester polymer to which an aromatic dicarboxylic acid component containing a sulfonate group, adipic acid and / or PEG is added, especially the dyeability by a cationic dye is used. And can be suitably used in fields requiring dyeability.

Claims (1)

Claims: 1. The composite ratio of a core component and a sheath component is 10 /
A core / sheath composite fiber of 90 to 50/50, and the core is made of titanium oxide coated with tin oxide on the surface thereof in an amount of 4 to 20 with respect to the mass of the core component.
The sheath portion is composed of polyethylene terephthalate containing 1.0 to 5.0 mol% of an aromatic dicarboxylic acid component containing a sulfonate group, and adipic acid and / or polyethylene having a molecular weight of 2000 or less. A heat-insulating and heat-retaining conjugate fiber comprising an easily dyeable polyester polymer containing 0.5 to 8.0% by mass of glycol.