JPH05331754A - Heat-absorbing and releasing nonwoven fabric of conjugate fiber - Google Patents

Abstract

PURPOSE:To provide a nonwoven fabric of conjugate fiber capable of absorbing or releasing heat according to the change in the body heat and the ambient temperature even in the absence of solar radiation, usable without restriction by color and suitable as a material for winter wear, sports wear, etc. CONSTITUTION:The heat-absorbing and releasing conjugate fiber nonwoven fabric is composed of a conjugate fiber consisting of a thermoplastic polymer component A having a melting point of 15-50 deg.C, a heat of fusion of >=10mJ/mg, a cooling crystallization temperature of <=40 deg.C and a crystallization heat of >=10mJ/mg and a thermoplastic polymer component B having a melting point or softening point of >=110 deg.C, wherein the polymer component B is present in a state to cover the fiber surface.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-woven fabric which has heat absorbing properties and is suitable as a material for winter clothes, sports clothes and the like.

[0002]

2. Description of the Related Art Conventionally, a three-layer structure cloth in which a batting material is inserted between a front material and a lining has been used as a material for winter clothes and sports clothes for the purpose of improving heat retention. This three-layer structure cloth is intended to improve the heat retaining property by the thickness of the air layer in the batting material.
However, when such a three-layered fabric is used as a material for winter clothing and sports clothing that requires particularly easy movement, the clothing is heavy and bulky when worn, and free movement is hindered. Had a problem. In recent years, in order to solve the above problems, it has been proposed to employ a non-woven fabric having a metal such as aluminum or titanium deposited on its surface as a batting material. However, such non-woven fabrics
Since the heat retention is improved only by absorbing the sun rays, there is a problem that the heat retention is not sufficiently improved when the irradiation of the sun rays is weak. However, there is a problem in that the use is limited.

[0003]

DISCLOSURE OF THE INVENTION The present invention solves the above problems and absorbs heat or generates heat in response to changes in body temperature or outside air temperature even without the irradiation of sunlight, thus limiting the application in terms of color tone. The present invention is intended to provide a non-woven fabric which is suitable as a material for cold weather clothing, sports clothing, etc.

[0004]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have included a thermoplastic polymer having a melting point and a crystallization temperature close to the body temperature or the outside temperature in the inside of the fiber. It was found that when a non-woven fabric composed of composite fibers is adopted as a batting material, a non-woven fabric having heat absorption and exothermic properties while maintaining practically sufficient performance as a batting material can be obtained.
The present invention has been reached. That is, the present invention relates to a thermoplastic polymer component A having a melting point of 15 to 50 ° C, a heat of fusion of 10 mJ / mg or more, a cooling crystallization temperature of 40 ° C or less, and a heat of crystallization of 10 mJ / mg or more, and a melting point or softening. Point temperature is 11
A heat-absorbing composite fiber nonwoven fabric comprising a thermoplastic polymer component B having a temperature of 0 ° C. or higher, and the polymer component B being composed of a composite fiber coating the fiber surface. is there.

Next, the composite fiber constituting the nonwoven fabric of the present invention will be described. The thermoplastic polymer component A in the present invention needs to have a melting point of 15 to 50 ° C, preferably 20 to 45 ° C, more preferably 3
It preferably has a melting point of 0 to 40 ° C. If the melting point is too low, it will be in a molten state at room temperature, and if it is too high, it will not melt at the outside air temperature, and neither of them can achieve the above object of the present invention. Further, the polymer component A needs to have a temperature falling crystallization temperature of 40 ° C. or lower, preferably 35 ° C. or lower, more preferably 30 ° C. or lower. As a matter of course, crystallization occurs at a temperature lower than the melting point, and it is necessary for the constituent fibers of the nonwoven fabric to generate heat when the temperature of the outside air moves from a high temperature to a low temperature. It must be. Further, the polymer component A needs to have a heat of fusion and a heat of crystallization of 10 mJ / mg or more, preferably 30 mJ / mg or more, more preferably 50 mJ / mg or more. When the heat of fusion and the heat of crystallization are less than 10 mJ / mg, the endothermic property is not sufficiently developed, and the above object of the present invention cannot be achieved. Such a polymer component A is obtained from a linear aliphatic dicarboxylic acid component and a linear aliphatic diol component, and examples of the linear aliphatic dicarboxylic acid include glutaric acid and adipic acid. , Pimelic acid or their ester-forming derivatives are examples of linear aliphatic diol components such as ethylene glycol, propanediol, 1,4-butanediol, 1,5-pentanediol or 1,6-hexane. Examples include diol and the like. The linear aliphatic dicarboxylic acid and linear aliphatic diol components may be used alone or in combination of two or more. Further, terephthalic acid, isophthalic acid, 5-sodium sulfoisophthalic acid, succinic acid, trimellitic acid, oxybenzoic acid, decane-1,10-dicarboxylic acid, octadecane-1 within the range that does not impair the endothermic and exothermic properties in the present invention. , 18-dicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, diethylene glycol, 1,4-cyclohexanedimethanol and the like may be used together as a copolymerization component. Further, if necessary, additives such as a matting agent, a stabilizer or a coloring agent may be added. Such polymer component A can be easily produced by a conventional method. That is, it can be produced by subjecting a linear aliphatic dicarboxylic acid component and a linear aliphatic diol component to an esterification reaction or a transesterification reaction and then a polycondensation reaction. The temperature-lowering crystallization temperature of the polymer component A can be adjusted by incorporating a crystal nucleating agent into the polymer. Examples of the crystal nucleating agent include talc, silica, chopped glass strands, and dioxide. Fine particles of inorganic compounds such as titanium, calcium silicate and antimony trioxide, fine particles of organic acid salts such as magnesium stearate and sodium benzoate, ethylene oxide adducts of disodium sulfobisphenol A, fluororesins, organic silicon, polyacrylic acid Examples thereof include crosslinked products, polystyrene crosslinked products, and fine particles of organic compounds such as polyarylate. These crystal nucleating agents may be used alone or in combination of two or more kinds. When the polymer nucleating agent is contained in the polymer component A, the content is 0.01 to the polymer.
It is preferably 3.0% by weight. If this content is less than 0.01% by weight, the effect as a crystal nucleating agent will be poor, while if it exceeds 3.0% by weight, the composite fiber will be easily cut during melt spinning or drawing, and spinning will also occur. It is not preferable because it causes problems such as accumulation on the filter in the spinneret pack and shortening of the life of the spinneret pack. When the polymer component A contains the crystal nucleating agent as described above, it may be added after the esterification reaction between the linear aliphatic dicarboxylic acid component and the linear aliphatic diol component or after the transesterification reaction. It may be added during the polycondensation reaction.

The thermoplastic polymer component B in the present invention is
It is necessary that its melting point or softening point temperature is 110 ° C. or higher, preferably 170 ° C. or higher, more preferably 210 ° C. or higher. If the melting point or softening point temperature is less than 110 ° C, the obtained nonwoven fabric cannot withstand hot water and ironing becomes difficult, which is not preferable. Examples of the polymer component B include polymers such as polyesters, polyamides, and polyolefins, and polyethylene terephthalate, polybutylene terephthalate, and polyesters containing these as a main component are particularly preferable.

The composite fiber constituting the nonwoven fabric of the present invention is composed of the above-mentioned polymer components A and B, and has a composite form in which the polymer component B covers the fiber surface.
The composite form is a concentric or eccentric core-sheath type in which the polymer component A is the core portion and the polymer component B is the sheath portion, and a sea-island type in which the polymer component A is the island portion and the polymer component B is the sea portion, the polymer component Examples of B include a multi-layer type in which the polymer component A is arranged in layers, and a core-sheath type is particularly preferable in terms of the effect of the present invention. The cross-sectional shape of the composite fiber is not particularly limited to a circular cross section, and may be a triangular shape, a quadrangular shape, or the like.
The composite ratio, that is, the weight ratio (B / A) of the polymer component B and the polymer component A is preferably 1/4 to 4/1. If the composite ratio of the polymer component B is low, the spinnability during melt spinning will be reduced, and the polymer component A will be exposed on the fiber surface, making it difficult to obtain a uniform nonwoven fabric. It is not preferable because it decreases. On the other hand, if the compounding ratio of the polymer component B is too high, the compounding ratio of the polymer component A will be too low, and the heat absorption and exothermic properties will not be sufficiently exhibited, and the above object of the present invention cannot be achieved.

Next, the nonwoven fabric of the present invention will be described. As described above, the nonwoven fabric of the present invention has a melting point of 15 to
50 ° C, thermoplastic polymer component A having a heat of fusion of 10 mJ / mg or more, a crystallization temperature of 40 ° C or less, a heat of crystallization of 10 mJ / mg or more, and a thermoplastic polymer having a melting point or softening point temperature of 110 ° C or more. The polymer component B is composed of a composite component B, and the polymer component B is composed of a composite fiber coating the fiber surface. This non-woven fabric preferably has a basis weight of 10 to 200 g / m ² . If the basis weight is less than 10 g / m ² , the thickness of the non-woven fabric is insufficient, so that heat absorption and exothermic properties are not sufficiently developed, and the above object of the present invention cannot be achieved.
On the other hand, if it exceeds 200 g / m ² , the non-woven fabric becomes heavy and bulky and unsuitable as a non-woven fabric for clothing.
Not preferable. The nonwoven fabric of the present invention can be used as it is, but may be used after being subjected to dyeing processing or resin processing, if necessary.

Next, regarding the method for producing the nonwoven fabric of the present invention,
explain. The nonwoven fabric of the present invention is produced by a method in which the polymer component A and the polymer component B are used as a composite component and melt-composite spinning is performed using a usual melt-composite spinning device, and the spun fiber is opened and then formed into a web. can do. That is, the polymer component A and the polymer component B are melt-composite-spun by using a normal melt-composite spinning device, and the spun-out composite fiber is drawn while being drawn by using a take-up means such as an air sucker, and an opening device is provided. The non-woven fabric of the present invention is obtained by opening the fiber by using the above-mentioned method, depositing it on a continuously moving mesh body to form a web, and subjecting the obtained web to an adhesive treatment to bond the constituent fibers. In this adhesion treatment, the web is impregnated with the adhesive, the heat-sealing fibers are mixed with the web and heat-treated to bond the heat-sealing fibers to the composite fibers, and the composite fibers are pushed by needle punching. Use a method of entanglement, a method of entanglement between composite fibers by high-pressure water flow treatment, a method of partially adhering between composite fibers through a web between a heated engraving roller and a roller with a smooth surface. However, a method using needle punching treatment or high-pressure water flow treatment is particularly preferable in that the inside of the composite fiber is not crushed. In addition,
The obtained non-woven fabric may be subjected to dyeing processing or resin processing, if necessary.

[0010]

The non-woven fabric of the present invention is composed of the above-mentioned composite fiber, and exhibits the endothermic property due to the heat of fusion absorbed when the thermoplastic polymer component A constituting the composite fiber is melted, and also has a crystal structure. The polymer component B having an endothermic exothermic property is not exposed on the fiber surface, and the fiber surface has a high melting point or a high softening point temperature. Since it is coated with the thermoplastic polymer component B having the above-mentioned properties, it exhibits exothermicity while maintaining the properties required for a nonwoven fabric for clothing.

[0011]

EXAMPLES Next, the present invention will be specifically described based on Examples. The intrinsic viscosity, melting point, cooling crystallization temperature, crystallization heat, softening point temperature and endothermic exothermicity in the examples were evaluated by the following methods. Intrinsic viscosity: Measured at a temperature of 20 ° C. using an equal weight mixture of phenol and ethane tetrachloride as a solvent. Melting point Tm and falling crystallization temperature Tc: Measured under the following conditions using a differential scanning calorimeter DSC-2 type manufactured by Perkin Elmer. That is, in a nitrogen stream, the temperature was raised from -30 ° C to a temperature of 280 ° C at a temperature rising rate of 10 ° C / min and held for 5 minutes, and then the temperature was lowered to -30 ° C at a temperature lowering rate of 10 ° C / min and held for 3 minutes. Then, the temperature rise rate is 10 ° C / min and the temperature is 28
The temperature was raised again to 0 ° C. and the measurement was performed. The peak value of the melting peak temperature curve when the temperature was raised again was taken as the melting point Tm, and the peak temperature of the crystallization peak temperature curve when the temperature was lowered was taken as the crystallization temperature Tc. Heat of fusion ΔHf and heat of crystallization ΔHc: Measured under the following conditions using a differential scanning calorimeter DSC-2 type manufactured by Perkin Elmer. That is, the melting peak area at the time of reheating was taken as the heat of melting ΔHf, and the crystallization peak area was taken as the heat of crystallization ΔHc. Softening point temperature: Automatic softening point measuring device AMP- manufactured by Yanagimoto Seisakusho
The temperature was measured at 30 ° C. at a temperature rising rate of 10 ° C./min using the 1st type. Endothermicity: One in which the non-woven fabric sample piece of the present invention and the non-woven fabric sample piece of polyethylene terephthalate fiber were attached to a metal plate and held in air at a temperature of 40 ° C. from room temperature to 60 ° C. from room temperature. The temperature of the sample was raised and kept for 30 minutes, then naturally cooled to 5 ° C. and kept, and the surface temperature of both sample pieces was observed by using an infrared imager Thermoviewer JTG-IB / IBT manufactured by JEOL Ltd. The endothermic and exothermic properties were evaluated based on the obtained difference in surface temperature.

Example 1 Glutaric acid (GA) and 1.6 times mol of 1,6-hexanediol (HD) with respect to glutaric acid were subjected to an esterification reaction by a conventional method, and the reaction product was added to 1 mol of GA. 3x
10 ⁻⁴ mol of tetrabutyl titanate was added as a catalyst and a polycondensation reaction was carried out at a temperature of 270 ° C. and 1 Torr for 3 hours to obtain a polyester polymer A. The obtained polyester polymer A has an intrinsic viscosity of 0.62 and a melting point Tm of 3
1 ° C, falling crystallization temperature Tc is 4 ° C, heat of fusion ΔHf is 53
mJ / mg, heat of crystallization ΔHc was 55 mJ / mg. Next, using polyester polymer A as a core component and polyethylene terephthalate polymer B having an intrinsic viscosity of 0.68 as a sheath component, a composite ratio (B /
A) is 1/1 and melt-spun, and the spun composite fiber is drawn and drawn by using an air sacker to obtain filament fiber having a single yarn fineness of 3 denier, which is opened and moved using an opening device. A web was formed by depositing on the mesh. Then, the obtained web was subjected to needle punching treatment to prepare a nonwoven fabric having a basis weight of 15 g / m ² . Table 1 shows various properties of the obtained nonwoven fabric.

Examples 2-6 and Comparative Examples 1-6 Intrinsic viscosity, melting point Tm, and falling crystallization temperature T of polymer component A
A nonwoven fabric was prepared in the same manner as in Example 1 except that c, heat of fusion ΔHf, and heat of crystallization ΔHc were changed as shown in Table 1. Table 1 shows various properties of the obtained nonwoven fabric.

Comparative Example 7 The polymer component A in Comparative Example 1 was used as a sheath component, and Table 1
A nonwoven fabric was prepared in the same manner as in Example 1 except that the polymer component shown in 1 was used as the core component. Table 1 shows various properties of the obtained nonwoven fabric. In this comparative example, melt spinnability was deteriorated and a uniform nonwoven fabric could not be obtained.

[0015]

[Table 1]

[0016]

EFFECT OF THE INVENTION The nonwoven fabric of the present invention is composed of the above-mentioned composite fibers, and when the thermoplastic polymer component A constituting the composite fibers melts, it exhibits endothermic properties by the heat of fusion absorbed and when it is crystallized. The polymer component B, which exhibits exothermicity due to the heat of crystallization that is exothermic, does not expose to the fiber surface, and the fiber surface has a high melting point or a high softening point temperature. Since it is covered with B, it retains the properties required as a non-woven fabric for clothing and exhibits heat absorption and exothermic properties. Therefore, it absorbs or generates heat in response to changes in body temperature or outside temperature even without irradiation of sunlight, and there are no restrictions on the use in terms of color tone, and it is suitable for use as a material for winter clothing, sports clothing, etc. You can

Claims (3)

[Claims] 1. A melting point of 15 to 50 ° C. and a heat of fusion of 10 mJ.
/ Mg or more, the temperature-lowering crystallization temperature is 40 ° C. or less, the heat of crystallization is 10 mJ / mg or more, and a thermoplastic polymer component B having a melting point or softening point temperature of 110 ° C. or more, An endothermic and exothermic composite fiber non-woven fabric characterized in that the polymer component B is composed of composite fibers covering the fiber surface. 2. The thermoplastic polymer component A has a melting point of 30-4.
A polyester having a temperature of 0 ° C., a heat of fusion of 50 mJ / mg or more, a crystallization temperature of 30 ° C. or less, and a heat of crystallization of 50 mJ / mg or more, and the thermoplastic polymer component B is polyethylene terephthalate, polybutylene terephthalate, or mainly these. The endothermic and exothermic composite fiber nonwoven fabric according to claim 1, which is a polyester. 3. The endothermic composite fiber nonwoven fabric according to claim 1 or 2, wherein the thermoplastic polymer component A is a linear aliphatic polyester.