JPH06192916A - Heat-resistant elastomeric hot-melt fiber - Google Patents

Abstract

PURPOSE:To provide a heat-resistant elastomeric hot-melt fiber capable of easily producing a cushioning material having excellent cushioning property and heat-resistant durability in high production efficiency without polluting the working environment. CONSTITUTION:The heat-resistant elastomeric hot-melt fiber is a conjugate fiber containing a hot-melt component consisting of a thermoplastic elastomer containing 1-10wt.% of a hindered antioxidant based on the soft segment, wherein the amount of the thermoplastic elastomer in the fiber is 10-70wt.% and the elastomer accounts for >=50% of the outer circumference of a cross-section of the fiber.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-resistant elastomer-based heat-bonded composite fiber, which has excellent heat-processability when a cushion material made of the fiber is thermoformed, and the obtained cushion material is excellent. The present invention relates to a heat-resistant elastomer-based heat-bonded composite fiber that provides cushioning properties and durability under normal temperature and heating.

[0002]

2. Description of the Related Art Currently, in the field of cushion materials such as furniture and beds, foamed urethane, polyester fiber stuffed cotton,
Also known are resin cotton and polyester hard cotton to which polyester fibers are adhered.

However, although urethane foam has good durability as a cushion, it has a great feeling of flooring, is poor in moisture permeability and has a heat storage property, and is easily steamed, and since it generates a large amount of heat during combustion, it imparts flame retardancy. Since it requires the addition of halides, it is incinerated due to the problem of poisoning due to the generation of toxic gas during a fire and the difficulty of recycling, but the incinerator is seriously damaged, and the cost of removing toxic gas is high. There is. Further, although it has excellent processability, it also has a problem of pollution of chemicals used during manufacturing. In addition, since the fibers are not fixed to each other in the polyester fiber wadding, the form may collapse during use, the fibers may move, and the crimp may cause the deterioration of bulkiness and elasticity. .

As a resin cotton in which polyester fibers are adhered with an adhesive, for example, a rubber-based adhesive is used, Japanese Patent Application Laid-Open No.
0-11352, JP-A 61-141388, JP-A 61-141391 and the like. Further, as a method using urethane, there is JP-A-61-137732. These cushion materials have poor durability,
In addition, there are problems such as not being able to recycle, complexity of processability and pollution of chemicals used during manufacturing.

Polyester hard cotton, for example, JP-A-58-3
1150, JP-A-2-154050, JP-A-3-220354, etc., but since an amorphous polymer having a brittle adhesive component of the heat-bonding fiber used is used (for example, JP-A-58). -136828, Japanese Patent Application Laid-Open No. 3-
However, there is a problem in that durability is poor such that the bonded portion is brittle and the bonded portion is easily broken during use and the form and elasticity are reduced. As an improved method, a method of entanglement treatment has been proposed in Japanese Patent Laid-Open No. 4-245965, but there is a problem that the brittleness of the bonded portion is not solved and the elasticity is largely reduced. In addition, there is complexity during processing. Further, there is a problem that the bonded portion is hard to be deformed and soft cushioning is hard to be imparted. For this reason, Japanese Patent Laid-Open No. 4-240219 proposes an improved method for a heat-bonded fiber using a polyester elastomer that is soft even at the bonded portion and recovers even when deformed. The polyester elastomer used for this fiber contains 50 to 80 mol% of terephthalic acid in the acid component of the hard segment, and the content of polyalkylene glycol as the soft segment is limited to 30 to 50% by weight. As other acid component composition, for example, isophthalic acid or the like is added to increase the amorphousness to increase the melting point to 18 as in the fiber described in JP-B-60-1404.
It is proposed that the temperature is 0 ° C. or lower, the heat-bonding molding temperature is kept low, the melt viscosity is improved by lowering the molecular weight to improve the fluidity, and the formation of the heat-bonding joint points is improved. Originally, the composition that easily plastically deforms under heating,
There is a problem that the heat resistance and compression resistance are lowered because the molecular weight becomes lower due to deterioration during thermoforming. Therefore, measures necessary for preventing thermal deterioration are disclosed in Japanese Patent Publication No. 60-1404 and Japanese Patent Laid-Open No.
-240219 discloses only that an antioxidant and an ultraviolet absorber may be contained. JP-A-3-220316 described as usable for other heat-bonded fibers
Similarly, no specific measures are described in the publication. This is clear from the fact that nothing is mentioned in the examples. A concrete description is described in JP-A-4-153316 as a polyurethane elastic fiber, as a thermoplastic elastomer fiber containing 0.1 to 3% by weight in total of an antioxidant and an ultraviolet absorber. As a preferable range, it is recommended that the UV absorber / antioxidant is 4/1 to 1/1 and the UV absorber is contained in a large amount. Then, when forming a fiber as a heat-bonding fiber, 260 to 290
Since it is spun at a high temperature of ℃, a considerable amount of toxic UV absorber sublimes, and there is a problem that it pollutes the working environment as fuming gas. When a fiber containing a large amount of an ultraviolet absorber is used as a heat-bonding fiber even after sublimation and smoke generation during melt spinning, the normal thermoforming temperature is maintained at a normal temperature of 180 ° C. or higher and 220 ° C. or lower for a longer time than during spinning, During such melt thermoforming, the toxic ultraviolet absorber sublimes, and becomes a serious problem as a fuming gas that contaminates the working environment significantly.

[0006]

DISCLOSURE OF THE INVENTION The present invention has improved the above-mentioned problems of the prior art by providing a cushioning material having excellent cushioning properties and excellent heat resistance and durability without polluting the working environment.
An object of the present invention is to provide a heat-resistant elastomer-based heat-bonded fiber suitable for easy production with high production efficiency.

[0007]

Means for Solving the Problems As a result of intensive studies for achieving the above object, the present inventors have found that oxidative decomposition of a soft segment that governs rubber elasticity of elastomer without adding an ultraviolet absorber. The present invention has been achieved by finding that the object can be achieved by suppressing the above. That is, the present invention is
A thermoadhesive composite fiber composed of a thermoplastic elastomer and a non-elastomer, and the thermoplastic elastomer component occupies 50% or more of the outer periphery of the cross section when viewed from the cross section of the thermoadhesive composite fiber, and the thermoplastic elastomer content in the fiber Is 10
70% by weight, and the thermoplastic elastomer is 20 to
A heat-resistant elastomeric heat comprising 80% by weight of a soft segment and 80 to 20% by weight of a hard segment, and containing 1 to 10% by weight of a hindered antioxidant with respect to all the soft segments. It is an adhesive fiber.

The heat-adhesive component constituting the heat-adhesive fiber of the present invention is required to be a thermoplastic elastomer having no covalent bond cross-linking point because it needs to be heat-melted and heat-bonded. As the thermoplastic elastomer, a polyester elastomer obtained by block-copolymerizing a polyether segment glycol having a molecular weight of 300 to 5,000 as a soft segment, a polyester glycol, a polycarbonate glycol, or the like,
Examples thereof include polyamide elastomers and polyurethane elastomers. However, from the most preferable use form of the present invention, since polyester fibers are often used for the matrix of the cushion material, it is preferable to use the polyester elastomer having good adhesiveness as the thermoplastic elastomer. As the polyester elastomer, a polyester ether block copolymer having a thermoplastic polyester as a hard segment and a polyalkylenediol as a soft segment, or a polyester ether block copolymer having an aliphatic polyester as a soft segment is used. A polymer can be illustrated. More specific examples of the polyester ether block copolymer include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, naphthalene 2.6 dicarboxylic acid, naphthalene 2.7 dicarboxylic acid, and diphenyl 4.4'dicarboxylic acid. At least one of alicyclic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid, aliphatic dicarboxylic acids such as succinic acid, adipic acid, sebacic acid dimer acid, and dicarboxylic acids selected from ester-forming derivatives thereof Seeds and 1.4 butanedio
, Ethylene glycol, trimethylene glycol, tetremethylene glycol, pentamethylene glycol,
Aliphatic diol such as hexamethylene glycol, 1.1
Cyclohexane dimethanol, at least one diol component selected from alicyclic diols such as 1,4-cyclohexane dimethanol, and ester-forming derivatives thereof, and an average molecular weight of about 300 A ternary block copolymer composed of at least one polyalkylenediol such as polyethylene glycol, polypropylene glycol, polytetramethylene glycol, ethylene oxide-propylene oxide copolymer, etc. is there. The polyester ester block copolymer is a ternary block copolymer composed of at least one of the above dicarboxylic acids, diol, and polyester diol such as polylactone having an average molecular weight of about 300 to 3,000. . Thermal adhesion, hydrolysis resistance, stretchability,
Considering heat resistance and the like, terephthalic acid is used as the dicarboxylic acid, or naphthalene 2.6 dicarboxylic acid, 1.4 butanediol is used as the diole component, and polytetramethylene glycol is used as the polyalkylenediol. The terpolymer block copolymer or the terpolymer block copolymer of polylactone as the polyester diol is particularly preferable.

The thermoplastic elastomer constituting the heat-adhesive component of the heat-adhesive fiber of the present invention has a large elastic recovery limit strain, does not easily undergo plastic deformation even when subjected to large deformation by a large force, and exhibits rubber elasticity. The content of the soft segment is 20 to 80% by weight because the recoverability is good and the heat resistance of the pseudo-crosslinking point due to the formation of the crystal structure is good. When the soft segment content is less than 20% by weight, the rubber elasticity peculiar to the elastomer is not sufficiently expressed, so that the cushioning property when formed into a cushioning material is inferior, which is not preferable. In addition, since the elastic recovery limit strain is small, plastic deformation is likely to occur when subjected to large deformation due to a large force, which is not preferable because the anti-sagging property after being formed into a cushion material is poor. On the other hand, when the content of the soft segment exceeds 80% by weight, the melting point is largely lowered and the recoverability at low temperature is improved, but the content of the hard segment is decreased, and the heat resistance of the pseudo-crosslinking point due to the formation of the crystal structure is reduced. As the cushioning material is deteriorated, the plastic deformation occurs at a relatively low temperature, for example, a temperature exceeding 40 ° C., and the heat resistance and sag resistance of the cushioning material is deteriorated. The preferred soft segment content in the present invention is 30 to 70% by weight, more preferably 40 to 65% by weight. The average molecular weight of the soft segment may be 300 to 5,000, but especially
When the repeating unit is increased in order to improve the heat resistance of the segment, it is preferably 500 to 4000, more preferably 1000 to 3000. A polyester elastomer preferable for the present invention is disclosed in, for example, Japanese Patent Application Laid-Open No.
It can be obtained by a conventional technique such as the publication of 5-120626.

The antioxidant contained in the thermoplastic elastomer constituting the heat-adhesive component of the present invention is a hinder containing a large number of sterically hindered methyl groups capable of trapping generated radicals in order to suppress thermal deterioration of the soft segment. It is necessary to contain an antioxidant. The hindered antioxidant includes hindered phenol type and hindered amine type, and the average molecular weight is preferably 300 to 5,000, more preferably 600 to 4,000. Average molecular weight is 300
Those less than 1 are not preferable because they are easily sublimated and disappear during heating. Further, a polycondensate having a high molecular weight of 8,000 or more tends to cause insufficient random migration in the elastomer, and a devising method is required. As a specific example, in a hindered phenol system, 1,3,5, trimethyl, 2,4,6, tris (3,5, di, t, butyl, 4, hydroxybenzyl) benzene, methylstyrene / pheno In particular, a polycondensation system and the like are preferable. Hinder
In the doamine type, dimethyl succinate with a molecular weight of 1000 or more.1. (2.hydroxyethyl) 4.hydroxy.2.
A 2,6,6-tetramethylpiperidine-based polycondensate and the like are particularly preferable. In the present invention, the antioxidant is contained in an amount of 1 to 10% by weight based on the soft segment content. If the amount is less than 1% by weight, the effect of suppressing thermal deterioration is reduced, and when thermoforming a cushion material, if it is processed in air at a temperature of 200 ° C. or higher for 10 minutes or longer, the elastomer may explode due to thermal deterioration. As the cushion structure itself becomes a deteriorated product, or even before the explosive thermal decomposition occurs, the molecular chain of the soft segment that produces rubber elasticity shortens due to thermal decomposition, or the network The structure is cut and the elasticity decreases, just before explosive thermal decomposition,
Since it becomes a wax-like substance having a low molecular weight and not having elasticity at all, the elastomer composition and processing conditions are extremely limited. In particular, as the soft segment content increases, explosive thermal decomposition occurs at a lower temperature in a shorter time, so the cushioning property as a cushioning material and the elastomer composition and processing conditions that improve durability at room temperature and under heating are optimized. It is not preferable because it becomes extremely difficult to make it. On the other hand, when the content exceeds 10% by weight, the antioxidant easily bleeds out on the fiber surface, and when the mixed fiber is opened for processing into a web to form a cushioning material, the antioxidant that has precipitated out of the heat-bonded fiber. The friction coefficient of the yarn becomes extremely high, resulting in poor spreading, making it difficult to uniformly mix the heat-bonded fibers with the fibers of the matrix, making the properties as a cushioning material non-uniform, and also reducing the average properties. . In an extreme case, there is a problem that the creaking between the yarns becomes large and pre-opening cannot be performed, which is not preferable. In addition, a polymer having a high molecular weight is difficult to bleed out, but it is not general because the cost is significantly increased. The content of the antioxidant per the preferred soft segment content of the present invention is 2 to 6% by weight, more preferably 3 to 5% by weight. Under particularly preferable antioxidant application conditions of the present invention, even in an elastomer having a soft segment content of 60% by weight or more, explosive thermal decomposition does not occur at a temperature of 210 ° C. in air for less than 15 minutes, A wide range of processing conditions can be selected, and since there are few molecular chain breaks in the soft segment, good stretchability can be maintained, so a cushioning material with excellent performance can be prepared. Furthermore, the effect of suppressing thermal decomposition is that the number of repeating units of the hard segment of the elastomer is increased to improve the heat resistance of the pseudo-crosslinking point, and the heat bonding can be performed at a higher processing temperature depending on the proportion of the melting point increasing. Since it is possible to improve the heat resistance at the bonding point of the prepared cushioning material and also maintain a high degree of stretchability, a cushioning material with extremely excellent performance can be prepared. As a means for evaluating the heat resistance of such an elastomer, the heat generation start temperature or heat generation start time is measured while raising the temperature by a differential scanning calorimeter (DSC) or by holding it at a constant temperature. Therefore, the heat resistance of the elastomer can be known. Incidentally, as a preferred method of adding the antioxidant in the present invention, when added in a large amount during the polymerization, it causes sublimation and troubles such as clogging of the polymerization vessel, and the addition effect is drastically reduced.
Preferably, after polymerization, kneading under pressure, uniaxially or 2
It is better to knead with a screw that has a high mixing function such as a dalmage on the shaft. Therefore, the thermoplastic elastomer constituting the heat-bonded fiber of the present invention does not contain an ultraviolet absorber. Therefore, the heat-bonded fiber of the present invention is added to 180 to 220.
Even during the heat-sealing process in which the temperature is kept at ℃ for a long time, no toxic fuming gas consisting of the ultraviolet absorber is generated, so that the working environment is not significantly polluted. When a thermoplastic elastomer having such heat resistance is used to form a sheath-core type structure as a preferred form of the heat-bondable fiber of the present invention, the non-elastomer component of the core component is polybutylene terephthalate. Polyethylene terephthalate (PET), polyethylene naphthalate (PE
N), polycyclohexylene dimethyl terephthalate (PCHDT) and other high melting point highly crystalline polyesters, so plastic deformation is less likely to occur.
The heat resistance and durability when used as a cushion material can also be improved.

The thermoadhesive fiber of the present invention is used for the purpose of forming a cushioning material by melting and flowing a thermoplastic elastomer, which is a thermoadhesive component, at a contact portion with a matrix fiber to form an adhesive point, so that The thermoplastic elastomer occupies at least 50% of the composite fiber surface, preferably the entire fiber surface, so that it can be heat-bonded at all of the contact portions, and the cushioning material is a network with the matrix fiber.
Since the structure is formed through the thermoplastic elastomer having excellent elasticity, the adhesive point with excellent elasticity easily deforms even if a large force or large deformation is applied from any direction,
Even if the individual fibers are slightly deformed, they can be propagated through the entire network structure through the bonding points and absorb the force and strain as a structure, so that the damage received by the individual fibers is significantly reduced. When the deforming force is released next, the rubber elasticity of the thermoplastic elastomer is developed and the thermoplastic elastomer is restored to the original shape, so that the durability is excellent, and this behavior is expressed as an appropriate repulsive force, which is excellent. Shows cushioning properties. If the thermoplastic elastomer is less than 50% of the surface of the composite fiber, the number of the above-mentioned adhesion points is small, so that it becomes difficult for the structure to absorb force and strain, and the damage received by each fiber becomes large, so that the structure becomes large. It is not preferable because the durability and cushioning property of the product will be deteriorated. The fiber structure of the present invention can be formed by a known method, for example, a side-by-side type or sheath-core type composite spinning, and can be obtained by drawing and crimping and then cutting to a desired fiber length.

In the present invention, the content of the thermoplastic elastomer in the heat-bonding fibers forming the elastic bonding points is 10 to 10.
It is 70% by weight. When the amount is less than 10% by weight, the amount of the thermoplastic elastomer forming the adhesive point is insufficient and the adhesive cross-sectional area becomes small, so that the deformation recovery force of the adhesive point decreases and the durability and elasticity as the cushioning material decrease, which is preferable. Absent.
On the other hand, if it exceeds 70% by weight, rubber elasticity is suppressed, and the non-elastic component that holds the dimensional stability of the heat-bonded fiber is reduced, so that it easily deforms in the processing stage such as opening, so the process passability is poor. Therefore, it is not preferable. A preferable thermoplastic elastomer content in the heat-bonded fiber is 30% by weight or more, more preferably 40 to 60% by weight.

The preferred crimped form of the heat-bondable fiber of the present invention is that when a three-dimensional crimp is developed during processing, the elastomer is sticky and the friction of the yarn is high, so that it is opened during card opening. From the viewpoint of processability, mechanical crimping with zigzag crimping is preferable because the fiber becomes defective. Mechanical crimps have 5 to 30 threads /
It can be used as long as the inch and the crimp ratio are in the range of 5 to 30%, but the number of crimps is preferably 10 to 25 threads / inch, and the crimp ratio is 10 to 25%. More preferably, the shape of the mechanical crimp is maintained during passage through the step, and when thermoformed into a cushion material,
It has a latent crimping ability to develop a spiral three-dimensional crimp. As a result, the bonding points can be formed three-dimensionally and a coiled network structure having a spring effect can be formed, so that the cushioning properties and durability are much better than those of the cushioning material having the ordinary ameber-shaped bonding points. Can be given. To form such a fiber structure, a side-by-side type may be used, but it is preferable to use an eccentric sheath-core type or a core-side type, and the core is preferably a side-by-side type or an eccentric sheath-core type. Further, by providing a hollow eccentric sheath core type or core score type that can further improve crimping ability and bending rigidity, the core is a side-by-side type or an eccentric core score type, so that the cushioning property and elasticity are high. Can be one. The stretching conditions for imparting a more preferable crimping ability of the present invention include stretching at a stretching temperature of 70 ° C. or less at a stretching ratio of about 0.8 to 0.9 times the breaking stretching ratio to impart mechanical crimping, and mechanical stretching. It can be obtained by feeding and cutting the cutter with a low tension so that the shrinkage does not extend. When stretched at a high temperature, a three-dimensional crimp is developed after the crimp is applied or in the processing step, which makes it difficult to open the fiber.

The fineness of the heat-bonding fiber of the present invention is not particularly limited, but if the fineness is too large, the number of constituents in the case of forming a fibrous structure decreases, the network structure becomes rough, and it becomes difficult to disperse the force. . On the other hand, when the fibers of the matrix have a large fineness, if the fineness of the heat-adhesive fibers is too small, it becomes difficult to mix fibers, and it becomes difficult to form a uniform network structure.
If the fineness of the heat-bonded fiber is extremely thin, it will be difficult to open the fiber. Therefore, the range of 2 to 15 denier is usually preferable. It is preferable to use an oil agent which is not easily decomposed by heat, for example, a phosphate salt such as potassium lauryl phosphate or potassium cetyl phosphate. In addition, it is particularly preferable to use an oil agent having a low friction coefficient because the openability is improved. The heat-adhesive fiber of the present invention may be made into a fiber aggregate such as a non-woven fabric or a cushioning material alone, but it is a mixture aggregate with other fibers (matrix fiber or matrix) containing 5 wt% or more of the heat-adhesive fiber. You can PE is a preferable mixed base material.
There are fibers made of polyester with high melting point and high crystallinity such as T, PEN, PCHDT and PBT, and also has good adhesiveness, excellent cushioning property, excellent heat resistance and durability, does not easily get damp when worn, and can be recycled. It is possible to easily manufacture a fiber assembly that serves as a polyester cushion material. Incidentally, a fiber assembly containing a particularly preferred heat-bonded fiber of the present invention is compressed to an arbitrary density before thermoforming, and heat-treated to form a entanglement point due to crimp expression, and the entanglement point and the contact point are fused. To be integrated, the melting point of the heat-adhesive component is higher by 10 to 120 ° C., preferably 20 to 100.
Thermoformed at a temperature as high as ℃, you can get a fiber molding of any density and hardness. Then, once it is cooled and solidified, it is heat-treated at a temperature lower than the melting point of the heat-adhesive component by at least 10 ° C., and preferably heat-treated with a strain of 10% or more. Sexuality is greatly improved. Note that this effect is significantly reduced as the acid component of the adhesive component contains more amorphous component.

[0015]

【Example】

 Examples 1 to 4, Comparative Examples 1 to 6, and Reference Example 1

Dimethyl terephthalate (D
MT) and 1,4-butanediol and polytetramethylene glycol (PTMG) as a glycol component are charged together with a small amount of a catalyst and a stabilizer, and after a transesterification reaction by a known method, polycondensation is performed while heating and reducing pressure. To produce a polyester ether block copolymer. The polyester ether block copolymer is dried by heating under vacuum, and 1,3,5, trimethyl, 2,4,6, tris (3
・ 5 ・ di ・ t ・ butyl ・ 4 ・ hydroxybenzyl) benzene (TTtBHB) or methylstyrene / phenol polycondensate (MSP400) having an average molecular weight of 3000 is used in a twin-screw extruder in an amount of 0 to 11 per soft segment. %
The melt-kneaded product was pelletized, and water was sufficiently removed with a heated inert gas to be used as a heat-adhesive component. Table 1 shows the formulation and characteristics of the obtained polyester ether block copolymer. As a UV absorber for reference, 2 ・ (2 '
-Hydroxy-3'-5'-diacylphenyl) benzotriazole (HDFB) 5 per soft segment
It was prepared in the same manner as that in which the composition was melt-kneaded by weight%. The heat generation start temperature of the polymer is measured by keeping it at 210 ° C. in air.

[0017]

[Table 1]

The obtained polyester ether block copolymer is used as a sheath component and PET is used as a core component, and the spinning temperature is 280 ° C. by an ordinary method so that the weight ratio of the sheath / core is eccentric. Was spun to obtain an unstretched yarn. The degree of eccentricity is a value obtained by dividing the value (L + R) obtained by adding the distance L from the center of the fiber to the center of the core and the radius R of the fiber by L ((L +
R) / L) was set to 1.15. Then 50
Stretched 3.4 times in a hot bath at ℃, mechanically crimped with a crimper, and fed to the cutter with a tension that prevents the mechanical crimps from stretching.
It was cut into 1 mm to prepare a 4-denier heat-bonded fiber. For comparison, a side-by-side type (S / S) weight ratio of polyester ether block copolymer / PET of 30 /
70 composite fibers were similarly prepared. The properties of the fibers obtained are shown in Table 2. Assuming that the relative viscosity of the polyester ether block copolymer in the fiber establishes additivity to the solution viscosity, the relative viscosity of the fiber obtained by supplying PET to both components under the same conditions as the spinning conditions of PET. It was determined as a relative viscosity corrected by the viscosity and the composition ratio of the conjugate fiber. The amount of the antioxidant in the fiber was determined by extracting the antioxidant in the fiber with a solvent, separating and removing impurities, and then quantitatively analyzing the additive composition as a comparative blank and correcting the composition ratio. The fiber surface occupation rate of the polyester ether block copolymer was determined from the fiber cross section. To deposit the antioxidant on the yarn surface, sprinkle the fiber and KBr powder, attach the antioxidant on the fiber surface to KBr powder, take an infrared spectrum pattern, and confirm the presence of the antioxidant. The fiber surface was observed for its deposited state with a scanning electron microscope. The adhesive state was judged by the ease with which the fibers were separated when the fibers were opened by hand.

[0019]

[Table 2]

30% of the obtained heat-bonded fiber having mechanical crimp
Outside with a hollow of 13% denier made by the conventional method and weight%
PET short fibers having a three-dimensional crimp in a cross section having three protrusions
Wafer obtained by mixing and opening fiber with 70% by weight of card
The density is 0.03g / cm ³So that it becomes 2
Heat treatment for 5 minutes by forcibly penetrating hot air of 00 to 230 ° C
Then, once cooled, the density is 0.04 g / cm³When
And heat-treat for 30 minutes at 100 ℃,
A plate-shaped cushion material was obtained. If the spread is poor, mix it by hand.
Although it was opened with a squeezing card, nep etc. also occur, and mixed fibers
It will be insufficient. Creation status of the obtained cushion material
Table 3 shows the characteristics and heating test results. In addition, heating test
Is an open-mixed web with a density of 0.03 g / cm³When
Compressed so that the hot air of 210 ℃ is forced to penetrate,
Measure the temperature with a heat sensor in the web,
The time until the temperature rises is shown. Compressive residual strain of 70 ℃
However, the repetitive compression residual strain at room temperature and the impact resilience are JI
According to the method of SK-6401.

[0021]

[Table 3]

In Examples 1 to 4 of the present invention, an appropriate amount of antioxidant is added, and it is possible to obtain a product having excellent heat resistance, excellent moldability of cushion material, and excellent performance of cushion material. In Comparative Example 1 and Comparative Example 5, the amount of soft segment of the elastomer of the heat-bonded fiber of the present invention is deviated. Heat resistance is good because an appropriate amount of antioxidant is added, but
Compared to Examples 1 to 4 of the present invention, Comparative Example 1 has a too large amount of soft segment, a decrease in heat resistance due to a decrease in melting point, an increase in adhesiveness, and poor opening, resulting in poor cushioning properties. Becomes Comparative Example 5 has a small amount of soft segments and thus has a low rubber elasticity function, and is easily plastically deformed.
The characteristics of the cushion material will be inferior. Comparative Examples 2 and 3 have a small amount of antioxidant added. The obtained cushioning material has relatively good characteristics because it has a coil spring-like network structure in which heat-bonding fibers are wound around matrix fibers and heat-bonded, but the amount of antioxidant added is Since the amount is small, the heat resistance is extremely poor. Comparative Example 4 is an example in which the amount of the antioxidant added was too large and bleeds out on the surface of the fiber to significantly reduce the openability. For this reason. Although the heat resistance is good, the characteristics of the cushion material obtained are inferior. Reference Example 1 is an example in which an ultraviolet absorber was added. Smoke generation during spinning is significant and pollutes the environment. Furthermore, during thermoforming, smoke was emitted and the processing machine was soiled. Moreover, the ultraviolet absorber accelerates the thermal decomposition probably because it does not suppress the thermal decomposition, and the workability is poor. Only the performance of the obtained cushioning material is remarkably inferior. In Comparative Example 6, since the proportion of the heat-adhesive component on the surface of the heat-adhesive fiber is less than the present invention,
The resulting cushioning material has fewer bonding points due to heat bonding, and the sag resistance is reduced. The cushion materials obtained from the fibers of the present invention and the comparative example are all heat-bonded and then re-heat-treated to significantly improve the elastic recovery of the elastomer by pseudo-crystallization, and the matrix fibers Since the heat-bonded fiber has a coil spring-like network structure wrapped around it, the characteristics are an example in which the characteristics are further improved as compared with the case where only the heat fusion treatment is performed.

Example 5, Comparative Examples 7-8

The polyester ether block copolymer of Experiment No. A-2 was used as a sheath component, and PET was used as a core component.
An unstretched yarn was obtained by spinning at a spinning temperature of 280 ° C. by a conventional method so that the weight ratio of the core was 5/95 to 80/20.
Note that no eccentricity is applied. Then, in a 50 ° C warm bath,
It was stretched twice, mechanically crimped by a crimper, fed to a cutter with a tension such that the mechanical crimp did not extend, and cut into 51 mm to prepare a 4-denier heat-bonded fiber. The heat-bonded fiber having the mechanical crimp thus obtained was prepared by a conventional method in an amount of 30% by weight.
A hollow web of denier and 70% by weight of PET short fibers having a three-dimensional crimp in the cross section having three protrusions on the outside was mixed and opened with a card to obtain a web having a density of 0.03 g. / Cm ³
And was forced to penetrate with hot air at 200 ° C. and heat-treated for 5 minutes to obtain a flat cushion material. The characteristics of the obtained cushion material are shown in Table 4.

[0025]

[Table 4]

In Comparative Example 7, as compared with Example 5, the heat-adhesive component was remarkably small, and the formation of heat-adhesion points was insufficient, so that the process passability was good, but the durability was poor. In Comparative Example 8, the heat-adhesive component was significantly larger than that in Example 5, and the heat-adhesive fibers were unevenly stretched at the time of opening the fiber, and it was difficult to uniformly mix the fibers by shrinking due to rubber elasticity. The properties of the material will be inferior. Example 5 of the present invention has processability,
Cushion performance is also improved. Incidentally, the performance is generally inferior to that of the above example because it was produced in the same manner as an ordinary cushion material and no special effect was given.

[0027]

EFFECT OF THE INVENTION The heat-resistant elastomer-based heat-bonded fiber of the present invention has good processability when a cushioning material or the like is manufactured by using other fibers as a matrix, and is heat-treated at a high temperature particularly during thermoforming. However, it does not pollute the work environment because it produces almost no toxic gas, and has extremely excellent heat-resistant processability, which allows a wide range of processing conditions to be selected, and because there are few molecular chain breaks in the soft segment, good expansion and contraction. Since it retains its properties, it is possible to create a cushioning material with excellent performance.
Furthermore, the effect of suppressing thermal decomposition is that the number of repeating units of the hard segment of the elastomer is increased to improve the heat resistance of the pseudo-crosslinking point, and the heat bonding can be performed at a higher processing temperature depending on the proportion of the melting point increasing. The cushioning material that has been made has improved heat resistance at the bonding points, and at the same time, it can retain a high degree of elasticity, so it provides a cushioning material with extremely excellent cushioning properties and durability at room temperature and under heating. it can. Particularly, the adhesiveness with polyester fiber is good, the above-mentioned performance can be further improved, and the moisture and water permeability can be maintained, so that a comfortable seat with less stuffiness can be provided. The cushion material obtained by using the heat-resistant elastomer-based heat-adhesive fiber of the present invention is suitable for vehicles, ships, furniture and beds, but is particularly suitable for automobiles and trains. Other uses include non-woven fabric applications that take advantage of elasticity.
For example, sanitary base cloth, shoulder pads and cups, synthetic leather base cloth and base cloth for napped cloths, wading layers and interior materials that have good air permeability and can be bonded, heat insulating materials and shock absorbing materials that do not exceed 70 ° C, and Can be widely applied to stretchable knitted fabrics and the like by spinning.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Internal reference number FI Technical indication location D04H 1/54 B 7199-3B (72) Inventor Mitsuhiro Sakuda 1-1 Nada-cho, Iwakuni-shi, Yamaguchi Prefecture Toyobo Co., Ltd. Iwakuni Factory

Claims (1)

[Claims] 1. A heat-bonding composite fiber composed of a thermoplastic elastomer and a non-elastomer, wherein the thermoplastic elastomer component is 5 at the outer circumference of the cross-section when viewed from the cross-section of the heat-bonding composite fiber.
0% or more, the content of the thermoplastic elastomer in the fiber is 10 to 70% by weight, and the thermoplastic elastomer has 20 to 80% by weight of the soft segment and 80 to 80% by weight.
A heat-resistant elastomeric heat-bonded fiber comprising 20% by weight of a hard segment and containing 1 to 10% by weight of a hindered antioxidant with respect to all soft segments.