JPH0892818A - Polyester composite fiber - Google Patents

Abstract

(57) [Summary] [Structure] Polyester (A) with a melting point of 200 ° C or higher
And a polyether ester block copolymer (B) having a melting point of 160 to 200 ° C.,
(1) The terephthalic acid component and the isophthalic acid component account for 40 to 90 mol% and 10 to 40 mol% of the total acid component of the polyester block portion of the copolymer (B), respectively, and The 4-butadiol component accounts for 80 mol% or more, and the polyether portion of the copolymer (B) is composed of a bisphenol / alkylene oxide adduct component having a number average molecular weight of 1,000 to 4,000. The proportion W in the combined polymer (B) is 40 to 55% by weight, and when the proportion of the isophthalic acid component in the total acid component of the polyester block portion is I _S mol%, the following formula (i) is obtained. 60-W ≦ I _S (i) (3) The intrinsic viscosity of the copolymer (B) is 1.0 dl / g or more, and the oxidative decomposition initiation temperature is 200 ° C. or more. Polyester-based composite fiber. [Effect] A cushion material having excellent cushioning properties, durability and stability, and excellent breathability can be easily manufactured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-adhesive polyester-based conjugate fiber, and more particularly to a conjugate fiber suitable for adhering aromatic polyester-based fibers. More specifically, the present invention relates to a heat-adhesive conjugate fiber which has elastic properties particularly excellent in durability and which can be supplied industrially at low cost when used as a cushioning material such as a non-woven cotton stuffing made of polyester fiber.

[0002]

2. Description of the Related Art The applicant of the present application discloses, as described in JP-A-5-98516, a polyester-based heat-bonding composite fiber having a polyester component having a melting point of 200.degree.
In a composite fiber composed of a polyether ester block copolymer component having a melting point of 200 ° C. or less, the polyether ester block copolymer comprises (A) 40 to 90 mol% of terephthalic acid based on the total acid component, and isophthalic acid. 10
To 40 mol% of an acid component, (B) a glycol component mainly containing 1,4-butanediol, and (C) a poly (alkylene oxide) glycol component having an average molecular weight of 1000 to 4000. The copolymerization amount of the component (C) in the copolymer is 40 to 55% by weight and satisfies the following formula (i), and the intrinsic viscosity (IV) and melting point (Tm of the polyether ester block copolymer are ) And oxidative decomposition initiation temperature (Tdi) is (ii)
Satisfied ~ (iv) equation, (i) 60-Wc ≦ A I (ii) 1.0 ≦ IV (iii) 160 ≦ Tm ≦ 200 (iv) 200 ≦ Tdi [ However, Wc is the component (C) Copolymerization amount (wt%), AI
Represents the copolymerization ratio (mol%) of the isophthalic acid component to the total acid component], and proposes a polyester-based heat-adhesive conjugate fiber in which the polyether ester block copolymer component accounts for 30% or more in the fiber cross-section ratio did.

The polyester-based heat-adhesive conjugate fiber described in this publication further improves the cushioning properties of urethane foam conventionally used as a cushioning material, and is excellent in durability and stability of cushioning properties. It is a heat-bondable composite fiber suitable for manufacturing a cushioning material having high air permeability.

[0004]

DISCLOSURE OF THE INVENTION As a result of further research, the present inventors have found that when heat-bonded to form a cushion material,
Although a novel heat-adhesive conjugate fiber having excellent compression durability was found, the above publication does not disclose or suggest this.

An object of the present invention is to provide a new polyester-based composite fiber having a heat adhesive property. Another object of the present invention is to provide a polyester-based composite fiber, which is capable of giving a cushioning material obtained by heat-bonding, which is superior to conventional polyurethane foams in cushioning durability, stability and breathability. Is to provide. A further object of the present invention is to provide a polyester-based conjugate fiber that can be used to manufacture a cushioning material by a simple process.

[0006]

According to the present invention, a polyester (A) having a melting point of 200 ° C. or higher and a melting point of 160 to
A composite fiber comprising a polyether ester block copolymer (B) at 200 ° C., which comprises (1) a terephthalic acid component and a terephthalic acid component out of all the acid components in the polyester block portion of the polyether ester block copolymer (B). Isophthalic acid component is 40-90 mol% and 10-
40 mol% and 1,4-butanediol component accounts for 70 mol% or more of the total glycol component of the polyester block portion. (2) The polyether portion of the polyether ester block copolymer (B) Is a bisphenol having a number average molecular weight of 1,000 to 4,000.
An alkylene oxide adduct component, the bisphenol / alkylene oxide adduct component occupying 40% to 55% by weight of the block copolymer (B) in the block copolymer (B), and the isophthalic acid component being the polyester block portion. The following formula (i) is satisfied, when the proportion of the total acid component of the above is I _S mol%: 60-W ≦ I _S ··· (i) (3) Polyether ester block copolymer The intrinsic viscosity (o-chlorophenol solvent, measured at 35 ° C.) of (B) is 1.0 dl / g or more, and the oxidative decomposition initiation temperature of the block copolymer (B) is 200 ° C. or more. A characteristic polyester-based composite fiber is provided to achieve the above object of the present invention.

Hereinafter, the present invention will be described in detail, by which other objects, constitutions, advantages and effects of the present invention will be apparent.

As described above, the polyester-based conjugate fiber of the present invention comprises the polyester (A) having a melting point of 200 ° C. or higher and the polyetherester block copolymer (B) having a melting point of 160 to 200 ° C.

The polyester (A) is not particularly limited as long as it has a melting point of 200 ° C. or higher, preferably 210 to 300 ° C. and has a fiber-forming property. Among them, polyethylene terephthalate, polybutylene terephthalate,
Poly (1,4-cyclohexanedimethylene) terephthalate or a small amount thereof, preferably polyester (A)
A copolyester obtained by copolymerizing 30% by weight or less of the third component in the whole is preferable.

The copolymerization component preferably used is, for example, a dicarboxylic acid component such as isophthalic acid, adipic acid, sebacic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, 5-sodium sulfoisophthalic acid, propylene glycol or diethylene glycol. , Neopentylene glycol, polyethylene glycol, p-xylylene glycol, 1,4-cyclohexanedimethanol,
Examples include diol components such as 5-sodium sulforesorcin, polyfunctional carboxylic acid components such as trimellitic acid and pyromellitic acid, and bifunctional monocarboxylic acid components such as p-oxybenzoic acid and p-oxyethoxybenzoic acid. You can

The polyether ester block copolymer (B) which is another component of the conjugate fiber of the present invention is terephthalic acid based on the total acid component of the polyester block portion of the copolymer (B). Those containing 40 to 90 mol% of acid component, preferably 65 to 85 mol%, and 10 to 40 mol% of isophthalic acid component, preferably 15 to 35 mol% are used. The block copolymer (B) may contain 20 mol% or less of an acid component other than terephthalic acid and isophthalic acid. Preferable examples of the acid component that can be contained include phthalic acid, adipic acid, sebacic acid, azelaic acid, dodecanedioic acid, 2,6-naphthalenedicarboxylic acid, 5-sodium sulfoisophthalic acid, and 1,4-cyclohexanedicarboxylic acid. be able to.

The polyester block portion of the polyether ester block copolymer (B) contains 1,4-butanediol as a main glycol component. That is, 70 mol% or more, preferably 80 mol% or more of all glycol components are 1,4-butanediol components, and other glycol components are present within 30 mol% or less, preferably 50 mol% or less. May be. Other glycol components preferably used include ethylene glycol, trimethylene glycol, 1,5-pentanediol, 1,
6-hexanediol, diethylene glycol, 1,4
-Cyclohexanediol, 1,4-cyclohexanedimethanol and the like can be mentioned.

The polyether ester block copolymer (B) contains a bisphenol / alkylene oxide adduct component having an average molecular weight of 1,000 to 4,000, preferably 1,500 to 3,600, and the alkylene When the proportion of the oxide adduct component in the polyether ester block copolymer (B) is W% by weight, the following formula (ii) 40 ≦ W ≦ 55 (ii) Preferably, the following formula (Iii) 45 ≦ W ≦ 55 ... (iii) is satisfied.

The presence of the above-mentioned bisphenol / alkylene oxide adduct component in the polyetherester block copolymer (B) in the above-mentioned amount makes it possible to maintain the elastic recovery performance of the obtained conjugate fiber in a good condition. The mechanical properties, heat resistance, and light resistance of the cushion material obtained by the heat treatment are maintained well.

The above bisphenol / alkylene oxide adduct is represented by the following formula (1)

[0016]

[Chemical 2]

(In the formula, R ₁ , R ₂ , R ₃ and R ₄ are the same or different and each represents an alkylene group having 2 to 5 carbon atoms;
₅ represents a divalent organic group having 1 to ₅ carbon atoms or an oxygen atom, m, n, p and q represent the number of repeating units, provided that m
And the sum of p and q are each 1 or more, and l is 0 or 1.).

The following formula (2) is a specific example of R _{1 to} R _4.

[0019]

[Chemical 3]

The following can be mentioned. R
It is preferable that ₁ and R ₄ are straight chains without a branched chain because the polymerization rate is high at the time of producing the polyetherester block copolymer (B). Further, it is preferable that R _{1 to} R ₄ are all the same.

R _{5 in the} formula (1) is a divalent organic group, —SO ₂ —
And a group represented by the following formula or an oxygen atom, and as a specific preferable example of R ₅ , the following formula (3)

[0022]

[Chemical 4]

The following can be mentioned. In the formula (1), l is 0 or 1, and when l is 0, R ₅ does not exist and the two phenylene groups are directly bonded.

The bisphenol / alkylene oxide adduct component may be present in the polyether ester block copolymer (B) in one kind or in two or more kinds.

The weight ratio W% of the bisphenol / alkylene oxide adduct component in the polyether ester block copolymer (B) and isophthalic acid in the total acid component of the polyester block portion of the block copolymer (B). The proportion I _S mol% of the acid component is represented by the following formula (i) 60−W ≦ I _S ... (i)

Satisfies By satisfying the above formula (i), oxidative deterioration is reduced when the conjugate fiber of the present invention is heat-bonded in air, and the mechanical properties of the resulting nonwoven fabric and cushioning material are retained.

Next, the polyetherester block copolymer (B) used in the conjugate fiber of the present invention is used for the process stability during the production of the conjugate fiber, the thermal adhesiveness of the conjugate fiber, the elastic properties of the adhesive-treated product, etc. In order to ensure the quality of the block copolymer (B), the intrinsic viscosity (IV) of the block copolymer (B) is 1.0 dl /
g or more, preferably 1.1 to 1.5 dl / g, melting point (T
m) is 160 to 200 ° C., preferably 165 to 190
C., and the oxidative decomposition initiation temperature (Tdi) is 200.degree. C. or higher, preferably 210.degree. C. or higher.

Here, IV is measured in a 35 ° C. orthochlorophenol solution, and Tm is a differential scanning calorimeter (DS).
C), and Tdi is a value measured by DSC in an air atmosphere.

When the IV is within the above range, the mechanical properties and elastic performance of the heat-bonded product such as the obtained nonwoven fabric and cushioning material can be maintained well. Further, when the Tm is in the above range, the heat treatment temperature is set to 2 when the composite fiber of the present invention is heat-bonded to produce the heat-bonded product.
The temperature can be set to an appropriate temperature of about 00 ° C, and oxidative decomposition of the polyetherester block copolymer (B) can be prevented.

When Tdi is in the above range, oxidative deterioration of the block copolymer (B) can be prevented during the heat-bonding treatment.

The polyether ester block copolymer (B) described in detail above can be produced according to a conventionally known method for producing a general copolymerized polyester. Specifically, a terephthalic acid component, an isophthalic acid component, and a dicarboxylic acid component other than these, a glycol component mainly containing 1,4-butanediol, and a bisphenol / alkylene oxide adduct are supplied to the reactor, There may be mentioned a method in which a transesterification reaction or an esterification reaction is carried out in the presence or absence of a catalyst, and then a polycondensation reaction is carried out in the presence of a catalyst under high vacuum to raise the polymerization degree to a desired degree. At this time, it is preferable to add an antioxidant such as a hindered phenol compound or a hindered amine compound, if necessary.

Further, since the relationship among the component ratio of each component of the block copolymer (B), the intrinsic viscosity, the melting point and the thermal decomposition starting temperature can be known in advance experimentally, the block satisfying the above-mentioned various conditions can be obtained. The copolymer (B) can be easily produced.

In the present invention, the polyether ester block copolymer (B) includes a matting agent, a pigment (for example, carbon black), an ultraviolet absorber (for example, a benzophenone-based compound), as in ordinary polyesters. , Benzotriazole compounds, salicylate compounds, etc.), crosslinking agents (isocyanate compounds, etc.) and the like.

The polyester-based conjugate fiber of the present invention is a polyester (A) having a melting point of 200 ° C. or higher as described above.
And a polyether ester block copolymer (B) at 200 ° C. or lower are composite-spun. In this case, the composite ratio is not particularly limited, but the ratio of the block copolymer (B) to the entire circumference of the cross section of the composite fiber, that is, the fiber cross sectional area ratio is preferably 30% or more.

The term "fiber cross-sectional area ratio" as used herein means the area of [(polyester (B)) / (area of polyester (A)] obtained by image analysis of the cross-section that appears when the composite fiber is cut perpendicular to the fiber direction. + Area of polyester (B))] ×
It is defined as a value obtained by calculation by 100 (%).

The cross-sectional shape of the polyester-based conjugate fiber of the present invention is preferably a core-sheath type or an eccentric core-sheath type in which it is eccentric. Among them, the core-sheath type composite fiber is preferable because the crimpability can be easily expressed by heat treatment or the like, and thus the passability in the card process is improved.

Further, the polyester-based conjugate fiber of the present invention is preferably a fiber which has been stretched 1.5 times or more, preferably 2 to 6 times. The cushion material formed of the stretched fibers is superior in elasticity to the cushion material made of the non-stretched fibers and is less tired. The reason for this is not clear, but in the process of heat treatment of the stretched fiber in a relaxed state, relaxation of the amorphous part of the polyether ester block copolymer (B) occurs, resulting in a polymer structure with more excellent elastic properties. It is presumed that the structure is maintained even after being molded into a cushion material or the like.

The polyester-based composite fiber of the present invention preferably has a low shrinkage, and is preferably heat-set after stretching. That is, if the shrinkage ratio is high, the shrinkage is significantly contracted during the heat-bonding process, so that the heat-bonding efficiency between the fibers is lowered and the repulsion property of the obtained cushioning material is lowered, and also the cushioning material has an extremely hard texture.

The polyester-based conjugate fiber of the present invention may be a fiber aggregate such as a non-woven fabric or a cushion material alone, but may be a mixture aggregate with other fibers containing 20% by weight or more of the conjugate fiber. Among them, as mixed fibers, polyethylene terephthalate, polybutylene terephthalate,
In the case of combining fibers made of polyester such as poly (cyclohexanedimethylene) terephthalate, not only the composite fibers of the present invention but also the thermal adhesion between the mixed fibers and the composite fibers are good, and the mechanical properties and It is possible to obtain a fiber assembly such as a cushion material having excellent elastic properties.

In order to fuse and integrate the fiber assembly containing the conjugate fiber of the present invention by heat treatment, the melting point of the polyether ester block copolymer (B) is 20-40.
It can be carried out by treating at a temperature that is higher than the melting point of the polyester component constituting the conjugate fiber and the other fiber mixed in the fiber assembly by a temperature higher than the temperature of ℃. By doing so, the molten polymer flows and bonds well to the entangled portion, and the entangled portion of the fibers is heat-sealed and integrated. In addition, the block copolymer (B) is unlikely to be deteriorated by heat.

[0041]

The present invention will be described below in detail with reference to examples. In the examples, all "parts" indicate parts by weight. In addition,
The evaluation in the examples was measured by the following method.

1. Intrinsic viscosity (IV) It measured at 35 degreeC using the ortho chlorofeil solvent.

2. Melting point (Tm) manufactured by Du Pont, using differential scanning calorimeter 1090 type,
Measured at an air flow rate of 90 ml / min and a heating rate of 20 ° C / min,
The melting peak temperature was determined.

3. Oxidative decomposition initiation temperature (Tdi) using a DuPont differential scanning calorimeter 1090 type,
Measured at an air flow rate of 90 ml / min and a heating rate of 20 ° C / min,
The oxidative decomposition start temperature was determined.

4. Measurement of compression elasticity and compression durability of cushion material Density molded into a flat plate 0.035 g / cm ³ , thickness 5c
The cushion material of m was compressed by 1 cm with a cylindrical rod having a flat lower surface with a cross-sectional area of 20 cm ² , and the stress (initial stress) was measured. After the measurement, the sample was compressed with a load of 800 g / cm ² for 10 seconds, then de-loaded and left standing for 5 seconds to repeat compression and standing, and after 24 hours, the compressive stress was measured again. The ratio% of the stress after repeated compression to the initial stress was defined as the compression durability of the cushion material.

(Examples 1 to 3 and Comparative Examples 1 to 6) 117.1 parts of dimethyl terephthalate, the amount of dimethyl isophthalate and 1,4-butanediol shown in Table 1 (1.4 mole times the acid component) A bisphenol A / ethylene oxide adduct represented by the following formula (4):

[0047]

[Chemical 5]

Then, tetrabutyl titanate (0.090 mol% with respect to the acid component) was charged into the reactor, and the internal temperature was set to 190.
The transesterification reaction was carried out at ° C. After about 80% of the theoretical amount of methanol had been distilled, the polycondensation reaction was started by raising the temperature and reducing the pressure. The polycondensation reaction is carried out while gradually reducing the pressure to 1 m.
After reaching a vacuum of mHg or less, the reaction was performed at 240 ° C. for 200 minutes, and then the antioxidant Irganox 1010 was added in an amount of 5% by weight with respect to polytetramethylene glycol to complete the reaction.

After pelletizing the produced polyetherester block copolymer (B), this polyetherester block copolymer (B) is used as a sheath, polyethylene terephthalate (A) is used as a core, and the weight of the core / sheath. 50/5 in comparison
The fiber was spun by a conventional method so that it would be 0. The conjugate fiber is an eccentric core-sheath type conjugate fiber. This fiber was drawn 2.0 times, cut into 64 mm, and then heat treated with warm water at 95 ° C.
After reducing the shrinkage and developing the crimp, and drying, an oil agent was applied. The single yarn fineness of the composite short fibers obtained here is 6 denier.

40% of composite short fibers containing this polyetherester block copolymer (B) and 60% of hollow section polyethylene terephthalate short fibers having a single yarn fineness of 6 denier and a fiber length of 64 mm obtained by a conventional method. To obtain a web (web bulk 120 cm ³ / g). This web is layered, thickness 5 cm, density 0.035
Put in a flat plate mold so that the g / cm ³ becomes 1 at 200 ° C.
Heat treatment was performed for 0 minutes to obtain a flat plate type cushion material. The characteristics of the obtained cushion material are shown in Table 1.

Comparative Example 7 A polymer obtained by polymerizing the phenol A / ethylene oxide adduct in Example 1 by replacing polytetramethylene glycol is used in place of the polyether ester block copolymer (B). Others were the same as Example 1.

[0052]

[Table 1]

[0053]

EFFECT OF THE INVENTION In the fiber assembly comprising the polyester-based heat-adhesive conjugate fiber of the present invention, the fibers are thermally fused by heating. Since this fusion point is formed from the polyether ester block copolymer (B) having a specific performance,
There is no deterioration of properties such as elasticity and mechanical properties in the bonding process, and the strength and elasticity of the fiber assembly (deformation recovery)
Etc. are extremely excellent. In particular, when mixed with ordinary polyester short fibers to form a cushioning material, it has less initial hardness in compression than conventional foamed urethane foam, has a large resilience, and increases in proportion to the amount of compression. As a result, it is possible to obtain a product having excellent properties such as an extremely low feeling of bottom hitting, a low density and good breathability and no fear of getting stuffy. Further, since the adhesiveness between the fibers is also good, it has the characteristics that the bonded part during deformation is less likely to be broken, and it is easily deformed but has good recoverability, and its durability against repeated compression is as described above. 5-985
It is superior to the composite fiber disclosed in JP-A-1.

When producing a fiber assembly from the polyester-based conjugate fiber of the present invention, a uniform product can be easily obtained by a simple and short process of heat treatment after forming a web. Moreover, the hardness can be arbitrarily changed in both the thickness direction and the plane direction by changing the mixing ratio of fibers, the constitution, or the density of the fiber aggregate.

Therefore, the cushioning material using the composite fiber of the present invention is excellent in cushioning property, durability and stability, has high air permeability, is resistant to stuffiness, is less likely to cause unevenness in processing, and has a fiber processing condition and a mixing ratio. It is a cushioning material that can be easily diversified by changing the cushioning property, and its range of use is suitable for various cushioning materials, such as furniture, beds, bedding, and seat cushions.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display area D04H 1/54 A // C08G 63/16 NMD 63/672 NNH

Claims (3)

[Claims] 1. A composite fiber comprising a polyester (A) having a melting point of 200 ° C. or higher and a polyether ester block copolymer (B) having a melting point of 160 to 200 ° C., wherein: (1) the polyether ester Among all the acid components in the polyester block portion of the block copolymer (B), the terephthalic acid component and the isophthalic acid component are 40 to 9 respectively.
0 mol% and 10 to 40 mol% of the total glycol component of the polyester block portion and 1,4-
The butanediol component accounts for 70 mol% or more, (2)
The polyether portion of the polyether ester block copolymer (B) has a number average molecular weight of 1,000 to 4,000.
Of the bisphenol / alkylene oxide adduct component, and the proportion W of the bisphenol / alkylene oxide adduct component in the block copolymer (B).
When the weight% is 40 to 55% by weight and the proportion of the isophthalic acid component in the total acid component of the polyester block portion is I _S mol%, the following formula (i) is satisfied: 60-W ≦ I _S ... (i) (3) The polyether ester block copolymer (B) has an intrinsic viscosity (o-chlorophenol solvent, measured at 35 ° C) of 1.0 dl / g or more, and the block copolymer The polyester-based composite fiber, wherein the oxidative decomposition initiation temperature of the coalescence (B) is 200 ° C. or higher. 2. A bisphenol / alkylene oxide adduct is represented by the following formula (1): (In the formula, R ₁ , R ₂ , R ₃ and R ₄ are the same or different and represent an alkylene group having 2 to ₅ carbon atoms, R ₅ is a divalent organic group having 1 to ₅ carbon atoms, Represents a group represented by SO ₂ — or an oxygen atom, m, n, p and q represent the number of repeating units, provided that the sum of m and n and the sum of p and q are each 1 or more, and l is 0. Or 1), the polyester-based conjugate fiber according to claim 1. 3. The polyether ester block copolymer (B) accounts for 30% or more of the fiber cross-sectional area ratio.
Or the polyester-based conjugate fiber according to 2.