JP6716974B2 - Non-woven - Google Patents

Description

INDUSTRIAL APPLICABILITY The present invention provides latent crimps which have excellent latent crimping properties, can be dyed with a disperse dye at a dyeing temperature of less than 100° C., and are capable of suitably obtaining a wrinkle-free, high-quality colored nonwoven fabric having excellent stretchability. The present invention relates to an easily dyeable polyester conjugate fiber and a non-woven fabric made of the same.

BACKGROUND ART Conventionally, stretchable nonwoven fabrics have been used for various purposes. In particular, in the medical field and cosmetics field, due to its excellent elasticity, it is used as a patch base fabric that follows the movement of affected areas such as joints, or as a patch for cosmetics due to the fineness and softness of the surface condition. There is.

In general, a white nonwoven fabric containing no coloring component has been preferred as the nonwoven fabric having elasticity. This is because the patch base fabric for pharmaceuticals or non-pharmaceutical parts is required to comply with various test items including the purity test from the viewpoint of safety, and it is a constraint on coloring. Is large. However, in recent years, from the viewpoint of pursuing high added value in terms of appearance, the demand for a stretchable colored nonwoven fabric is rapidly increasing.

Generally, stretchable colored non-woven fabrics are entangled with latent crimpable polyester fibers by needle punching, spunlacing, etc., and then heat treated to produce fine spiral crimps on the fibers. Then, stretchability is imparted to produce a stretchable nonwoven fabric, which is colored by a beam dyeing method or the like.

Examples of the latently crimpable polyester fibers used for the production of such a colored nonwoven fabric having elasticity include 2,2-bis[4-(2-hydroxyethoxy)phenyl]propane in an amount of 2 to 7 mol %. Latent crimpable polyester composite fiber using a copolyester obtained by copolymerizing 5 to 13 mol% of isophthalic acid (see Patent Document 1) and 3 to 6 mol% of a structural unit having a metal salt sulfonate group. A latent crimpable polyester conjugate fiber using the above-mentioned copolymerized polyester is known (see Patent Document 2).

However, these latent crimpable polyester conjugate fibers, while exhibiting excellent stretchability when made into a nonwoven fabric, on the other hand, it is necessary to dye under high temperature and high pressure in order to be sufficiently colored in the dyeing step after processing the nonwoven fabric, There is a problem that undesired shrinkage occurs due to the heat, and wrinkles and colored spots are generated on the nonwoven fabric, and the texture is hardened.

Further, it is known that fibers having a polyethylene terephthalate structure are difficult to be dyed, and when dyeing, for example, it is difficult to dye unless a dyeing pot is pressurized and the temperature is raised to 130°C. In order to solve the problem, many methods for improving dyeability by modifying a polyester resin have been studied so far.

For example, in order to improve the oxidative degradability of polyethylene glycol by copolymerizing polyethylene glycol having a number average molecular weight of 600 to 4000 or less in an amount of 3% by weight or more and 10% by weight or less, a modification in which a hindered phenol-based antioxidant coexists. A method for producing a modified polyester composition that facilitates dyeing by using a polyester composition has been proposed (see Patent Document 3).

However, in this proposed method, since a large amount of polyethylene glycol is copolymerized, the molecular structure of the molded product is not stable. For example, for the fiberized product, the dry heat shrinkage rate and delayed shrinkage are There is a problem that the rate is large and the product value is inferior. Further, this proposal has a problem that a large amount of polyethylene glycol is copolymerized in order to impart the dyeability under normal pressure dispersion, and when it is used as it is, the strength of the obtained molded product is lowered. In order to suppress this decrease in strength, it is necessary to use a hindered phenolic antioxidant in combination, but the hindered phenolic antioxidant itself undergoes a structural change due to ultraviolet rays, etc., and the molded product turns yellow. There is also a problem of being lost.

JP, 7-54216, A JP-A-62-78214 JP-A-2-38421

Therefore, the object of the present invention is excellent in stretchability in the nonwoven fabric, and in the dyeing step after the nonwoven fabric processing, dyeing with a disperse dye at a dyeing temperature of less than 100° C. is possible, and wrinkles and colored spots do not occur, It is an object of the present invention to provide a latently crimpable, easily dyed polyester conjugate fiber that can obtain a high-quality nonwoven fabric with a soft texture, and a nonwoven fabric made of the same.

The present inventors considered that a latently crimpable easily dyeable polyester conjugate fiber composed of a polyester (A) dyeable with a disperse dye under atmospheric pressure and a polyester (B) is suitable for the above problems. In addition, the present invention has been made by further studying the intrinsic viscosity of the polyester to be used and the composite ratio thereof.

That is, the latently crimpable dyeable polyester composite fiber of the present invention is a polyester whose main repeating component is ethylene terephthalate, and has 5 to 10 diol components having side chains of 3 with respect to all diol components. Mol% and the content of polyethylene glycol is 2 to 4% by mass, and the intrinsic viscosity is 0 than that of the atmospheric pressure disperse dyeable polyethylene terephthalate (A) and the above atmospheric pressure disperse dyeable polyester (A). It is a latently crimpable easily dyeable polyester conjugate fiber composed of a polyester (B) having a low content of 0.02 to 0.25 and having a number of developed crimps of 40 co/25 mm or more during heat treatment without load at a temperature of 180°C.

According to a preferred embodiment of the latently crimpable dyeable polyester conjugate fiber of the present invention, the intrinsic viscosity of the atmospheric pressure dispersible dyeable polyester (A) is 0.52 to 0.80, and the polyester (B ) Has an intrinsic viscosity of 0.50 to 0.75.

According to a preferred embodiment of the latently crimpable dyeable polyester conjugate fiber of the present invention, the composite ratio of the atmospheric pressure dispersible dyeable polyester (A) and the polyester (B) is (A)/mass ratio. (B)=60/40 to 40/60.

In the present invention, a nonwoven fabric can be manufactured using the latently crimpable dyeable polyester conjugate fiber. That is, the non-woven fabric of the present invention is a non-woven fabric containing 70% by mass or more of the latently crimpable easily dyed polyester conjugate fiber and having an elongation rate of 65% or more and an elongation recovery rate of 60% or more. is there.

According to the present invention, it is possible to obtain a high-quality non-woven fabric which is excellent in stretchability of a non-woven fabric, excellent in dyeing property of a disperse dye at a dyeing temperature of less than 100° C., does not cause wrinkles and colored spots, and is uniformly colored. A non-woven fabric made of latently crimpable and easily dyeable polyester conjugate fiber is obtained.

The latently crimpable dyeable polyester conjugate fiber used in the present invention is a polyester whose main repeating component is ethylene terephthalate, and has 5 to 10 diol components having side chains of 3 with respect to all diol components. Mol% and the atmospheric viscosity dispersible dyeable polyethylene terephthalate (A), which has a polyethylene glycol content of 2 to 4 mass %, and the above atmospheric pressure dispersible dyeable polyester (A) have an intrinsic viscosity of 0. It is a latently crimpable and easily dyeable polyester conjugate fiber composed of a polyester (B) having a low content of 02 to 0.25.

The main component of the atmospheric pressure disperse dye dyeable polyester (A) used in the present invention is a polyester obtained after an esterification reaction or a transesterification reaction of dicarboxylic acid or its ester derivative and diol or its ester derivative. Is.

The atmospheric pressure-dispersible dyeable polyester (A) used in the present invention comprises 70 mol% or more of ethylene terephthalate as a main repeating unit, and more preferably 80 mol% or more.

Specifically, in the atmospheric pressure disperse dye dyeable polyester (A) used in the present invention, the diol component having a side chain and having 3 carbon atoms is 5 to 10 mol %, and polyethylene glycol is 2 to 4 mol. It is important to include mass%. This requirement is essential for achieving both the structural stability when formed into fibers and the dyeability of the disperse dye under normal pressure. When either one of the diol component having a side chain of 3 carbon chains or the polyethylene glycol component is out of the above range, the dyeability of the disperse dye at a temperature of less than 100° C. and the fiber structure stability are compatible. You can't let it happen.

The content of the diol component and the polyethylene glycol is preferably 7 to 9 mol% of the diol component having a side chain and having 3 carbon atoms, and the proportion of polyethylene glycol is 2.5 to 3.5% by mass. is there.

The polyethylene glycol contained in the atmospheric pressure disperse dye dyeable polyester (A) used in the present invention has excellent dyeability to a disperse dye at atmospheric pressure when copolymerized in polyester, while it is copolymerized. It also has rubber elasticity afterwards. Therefore, the structure of the molecular chain becomes unstable when formed into a fiber, but by copolymerizing a diol component having a side chain portion and having 3 carbon chains, the side chain portion is a rubber of polyethylene glycol. The elasticity can be suppressed appropriately, the structure when formed into a fiber is stabilized, and the characteristic of easy dyeing property of polyethylene glycol is further improved.

That is, by co-polymerizing both polyethylene glycol and a diol component having a side chain and having 3 carbon atoms, the structural stability in fiberization, which has hitherto not been achieved, and the dispersibility of the disperse dye under normal pressure It is possible to achieve both dyeability.

Examples of the diol component having 3 side chains and having a side chain of the normal pressure disperse dye-dyeable polyester (A) used in the present invention include 2-methyl-1,3-propanediol and 2-ethyl-1,3. -Having side chains such as propanediol, 2-propyl-1,3-propanediol, 2-phenyl-1,3-propanediol, 2-methyl-1,3-propanediol, and ethylene oxide adducts thereof. A diol component having 3 carbon chains is used. Especially, when the steric hindrance of the side chain portion is too large, the effect on the dyeability and the fiber structure stability becomes small, and therefore 2-methyl-1,3-propanediol or 2-methyl having a methyl group at the side chain portion. An ethylene oxide adduct of -1,3-propanediol is preferably used. By using these diol components having a methyl group and having 3 carbon chains, it becomes easier to exert a synergistic effect with polyethylene glycol.

The number average molecular weight of the polyethylene glycol constituting the atmospheric pressure disperse dye dyeable polyester (A) used in the present invention is preferably a polyethylene glycol having a number average molecular weight in the range of 400 to 4000. More preferably, the smaller the molecular weight is, the more stable the fiber structure can be. Therefore, the more preferable number average molecular weight is 600 to 2,000.

The atmospheric pressure disperse dye dyeable polyester (A) used in the present invention contains a cyclic dimer in a proportion of 0.35% by mass or less, and the structure of the cyclic dimer is represented by the following formula (1). When the amount of cyclic dimer is reduced, the structural stability when formed into fibers is excellent. The ratio of cyclic dimers is preferably 0.30% by mass or less.

(Here, R1 and R2 represent a hydrocarbon group having 1 to 6 carbon atoms, a phenyl group, or an aryl group.)
For example, when the diol component having a side chain and having 3 carbon atoms is 2-methyl-1,3-propanediol, the cyclic dimer is represented by the following formula (2).

In the present invention, a polyester (B) having an intrinsic viscosity of 0.02 to 0.25 lower than that of the atmospheric pressure disperse dye dyeable polyester (A) used in the present invention may be compounded in a side-by-side type or an eccentric core-sheath type. It is necessary, and more preferably, the polyester (B) having an intrinsic viscosity of 0.05 to 0.20 lower is compounded. When the above-mentioned difference in intrinsic viscosity is less than 0.02, the difference in intrinsic viscosity from the atmospheric pressure disperse dye-dyeable polyester (A) becomes small, resulting in insufficient crimp expression, resulting in a nonwoven fabric. However, its elongation rate and elongation recovery rate are small and sufficient elasticity cannot be obtained. On the other hand, if the intrinsic viscosity is more than 0.25, the difference in the intrinsic viscosity from the atmospheric pressure disperse dye-dyeable polyester (A) becomes large, and it becomes difficult to produce fibers.

The atmospheric pressure disperse dye dyeable polyester (A) used in the present invention preferably has an intrinsic viscosity (o-chlorophenol, temperature 25° C.) in the range of 0.52 to 0.80, and more preferably It is in the range of 0.55 to 0.75. If the intrinsic viscosity is less than 0.52, the melt viscosity becomes low and it becomes difficult to produce fibers. On the other hand, if the intrinsic viscosity exceeds 0.80, the melt viscosity becomes high and it becomes difficult to produce fibers.

Examples of the polyester (B) used in the present invention include homopolymers such as polyethylene terephthalate, polybutylene terephthalate, polytrimethylene terephthalate, polyethylene naphthalate and polybutylene naphthalate. Is 65% or more, and it is important to obtain stretchability such that the elongation recovery rate is 60% or more, preferably the elongation rate of the nonwoven fabric is 70 to 80%, and the elongation recovery rate is in the range of 65 to 75%. Is.

The intrinsic viscosity (o-chlorophenol, temperature 25° C.) of the polyester (B) used in the present invention is preferably 0.50 to 0.75, more preferably 0.55 to 0.70. If the intrinsic viscosity is less than 0.50, the melt viscosity becomes low and it becomes difficult to produce fibers. On the other hand, when the intrinsic viscosity exceeds 0.75, the melt viscosity becomes high and it becomes difficult to produce fibers.

Further, in the present invention, the composite ratio of the atmospheric pressure disperse dye dyeable polyester (A) and the polyester (B) is preferably (A)/(B)=60/40 to 40/60 in terms of mass ratio. , And more preferably 60/40 to 50/50. When the composite ratio of the normal pressure disperse dye dyeable polyester (A) is less than 40%, the normal pressure disperse dyeability and the crimp development are insufficient, and when the dyed nonwoven fabric is used, the color specification value L is small. In addition, the elongation rate and elongation recovery rate are small, and sufficient dyeability and stretchability cannot be obtained. Further, even when the composite ratio of the atmospheric pressure disperse dye-dyeable polyester (A) exceeds 60%, the crimp expression is insufficient, and when it is made into a nonwoven fabric, its elongation rate and elongation recovery rate are small and sufficient expansion and contraction occur. I can not get sex.

When the composite ratio of the polyester (B) used in the present invention is less than 40%, the crimp developability becomes insufficient, and when it is used as a nonwoven fabric, its elongation rate and elongation recovery rate are small and sufficient elasticity is obtained. Absent. On the other hand, if the composite ratio of the polyester (B) exceeds 60%, the dispersibility under atmospheric pressure and the crimp developability become insufficient, and when the dyed nonwoven fabric is used, its colorimetric value L is small and the elongation ratio is high. And elongation recovery rate is small, and sufficient dyeability and stretchability cannot be obtained.

Further, the single-fiber fineness of the latently crimpable and easily dyeable polyester conjugate fiber used in the present invention is preferably 0.5 to 10.0 dtex, and more preferably 1.0 to 5.0 dtex. If the monofilament fineness is less than 0.5 dtex, the spunability and the card passing property are deteriorated, which may result in a non-woven fabric with poor texture. Further, if the single fiber fineness exceeds 10.0 dtex, a nonwoven fabric having thickness and roughness is obtained, and the fit may be lost.

The fiber length of the latently crimpable dyeable polyester conjugate fiber used in the present invention is preferably 20 to 80 mm. When the fiber length is less than 20 mm, the card passing property is poor, and the texture of the resulting nonwoven fabric tends to be poor. On the other hand, if the fiber length exceeds 80 mm, the entanglement of the fibers becomes too strong, so that the card passing property is poor, and the texture of the resulting nonwoven fabric tends to be poor.

The latently crimpable dyeable polyester conjugate fiber used in the present invention can be produced, for example, by the following yarn making method.

The atmospheric pressure disperse dye dyeable polyester (A) and the polyester (B) are melted and melted using a composite melt spinning device, and melt-spun at a spinning temperature preferably 20 to 40° C. higher than the melting point to give a predetermined mass. In terms of the ratio, through the spinneret for composite spinning having 150 to 700 discharge holes having a pore diameter of 0.3 to 0.6 mm, air spun from the spinneret with air at a temperature of 10 to 25° C. is 40 to 100 m/min. After being sprayed with the flow of No. 3, and then cooled, a spinning oil is applied, and the unstretched yarn tow is obtained by once storing in a can at a take-up speed of 900 to 1500 m/min.

Next, the obtained undrawn yarn tow is drawn at a draw ratio of 2.5 to 4.0 times using a liquid bath at a temperature of 75 to 95°C, and a tension heat treatment is performed at a temperature of 90°C to 180°C. Apply the latent crimping property by applying, mechanical crimping of 12 to 20 threads / 25 mm using a crimper, applying a finishing oil agent by spraying, and drying at a temperature of 60 to 150°C for 15 to 30 minutes, By cutting into a length of 20 to 80 mm, a latently crimpable dyeable polyester conjugate fiber having a single fiber fineness of 0.5 to 10.0 dtex can be produced.

In the present invention, a nonwoven fabric can be produced using the latently crimpable, easily dyed polyester conjugate fiber used in the present invention.

The nonwoven fabric produced in the present invention preferably contains 70% by mass or more of the latently crimpable dyeable polyester conjugate fiber used in the present invention. When the latently crimpable dyeable polyester composite fiber is less than 70% by mass, it is difficult to obtain a nonwoven fabric excellent in stretchability and dyeability under normal pressure disperse dye, which is the object of the present invention.

That is, in the non-woven fabric produced by the present invention, in addition to the latently crimpable easily dyed polyester conjugate fiber used in the present invention, in the range of less than 30% by mass, ordinary polyester fiber, thermal adhesive binder fiber, cotton, wool It is also possible to appropriately mix natural fibers such as hemp and hemp.

The non-woven fabric produced by the present invention includes the latently crimpable easily dyeable polyester conjugate fiber used in the present invention, which may be used alone or as required, in ordinary polyester fiber, heat-bonding binder fiber, cotton, wool and hemp. A cotton web is prepared by blending with natural fibers, and subjected to a carding machine. If necessary, the obtained fiber web is entangled by needle punching or spunlace, and the latent crimp of the present invention described above in a free state. A stretchable non-woven fabric can be obtained by heat-treating at a temperature 20 to 60° C. higher than the temperature of the tension heat treatment applied at the time of forming the easily dyeable polyester conjugate fiber to reveal the latent crimp.

It is important that the elongation rate of the nonwoven fabric produced in the present invention is 65% or more, and preferably in the range of 70 to 80%. If the elongation rate is less than 65%, it is difficult to apply it to applications requiring elasticity.

Further, it is important that the elongation recovery rate of the nonwoven fabric of the present invention is 60% or more, and preferably in the range of 65 to 75%. If the elongation recovery rate is less than 60%, it tends to be deformed by an external force.

The latently crimpable dyeable polyester conjugate fiber used in the present invention can be used as a spun yarn as well as a non-woven fabric, and they are used for applications requiring stretchability and fitability, and among them, for application as a sticking substrate. It can also be suitably used for woven and knitted products such as sports clothing and batting.

Next, the latently crimpable easily dyed polyester conjugate fiber of the present invention and the nonwoven fabric made of the same will be described in detail based on Examples. The method of measuring the characteristic value in the present invention is as follows.

(1) Intrinsic viscosity:
The intrinsic viscosity was measured with an Ubbelohde viscometer at a temperature of 35° C. using orthochlorophenol as a solvent. The intrinsic viscosity was measured three times or more and expressed as an average value.

(2) Positive single fiber fineness:
The single fiber fineness was measured according to JIS L1015 (2010).

(3) Unit weight of non-woven fabric:
The basis weight of the non-woven fabric was measured according to JIS-L1085 (1998).

(4) Nonwoven fabric elongation:
Regarding the elongation rate of the non-woven fabric, one end of the non-woven fabric test piece (5 cm width×about 60 cm length) is fixed with an upper clamp using a tensile tester, and an initial weight of 30 g is applied to the other end. Then mark at 20 cm or 50 cm intervals and gently apply a load of 240 g. The length between the marks after being left for 1 minute was measured, the average value of N=3 or more was calculated using the following formula 2, and the judgment was made according to the following criteria.
-Expansion rate (%)={(L1-L0)/L0}*100... Formula 2.
(Here, L0 represents the length between the original marks (20 cm or 50 cm), and L1 represents the length between the marks after a load of 240 g was applied for 1 minute.)
・Extension rate 65% or more: ○
-Elongation rate less than 65%: x.

(5) Elongation recovery rate of nonwoven fabric:
The elongation recovery rate was 20 cm or 50 cm between the grips under the initial load of 30 g using the same test piece as used for measuring the elongation rate and using a constant speed elongation type tensile tester with a self-recording device. The test piece was attached so that the tensile speed was 100% of the grip interval per minute. The test piece was extended to 80% of the elongation at a load of 240 g, the average value of N=3 or more was calculated by using the following formula 3, and judged according to the following criteria.
Elongation recovery rate (%)={(L10−L11)/L10}×100...Equation 3
(Here, L10 represents the elongation (cm) of 80% of the elongation at a load of 240 g, which was obtained at a 100% pulling rate per gripping interval per minute, and L11 represents the residual elongation after repeated loading five times ( cm).)
・Growth recovery rate 60% or more: ○
-Elongation recovery rate less than 60%: x.

(6) Dyeability of non-woven fabric:
As for the dyeability, the non-woven fabric has a temperature of 95° C. at a bath ratio of 1:15 consisting of Dye Terraseal Navy Blue GRL-C 0.9% owf and a dispersant “Nikka Sunsalt” (registered trademark) #1200 1.0% owf. Was dyed for 60 minutes in a hot aqueous solution, and the colorimetric value L was measured using a color difference meter (SM color computer model SM-3, manufactured by Suga Test Instruments Co., Ltd.), and judged according to the following criteria.
・Color value less than L25.0: ○
-Color value L25.0 or more: ×.

(7) Surface quality of dyed nonwoven fabric:
The surface quality of the non-woven fabric after dyeing was observed and judged according to the following criteria.
・No wrinkles on the surface of the non-woven fabric: ○
-There are wrinkles on the surface of the nonwoven fabric: x.

(Example 1)
A latently crimpable dyeable polyester composite fiber was produced by the following method. The normal pressure disperse dye dyeable polyester having 8 mol% of the diol component having a side chain of 3 and 3% by mass of polyethylene glycol and having an intrinsic viscosity of 0.60 with respect to the total diol component ( A) and polyester (B) having an intrinsic viscosity of 0.55 are mixed at a mass ratio of (A)/(B)=50/50 through a round hole spinneret having 350 discharge holes so as to have a spinning temperature. Melt spinning was performed at 280° C., and an undrawn yarn tow was obtained at a take-up speed of 1200 m/min.

Next, the obtained undrawn yarn tow was subjected to one-stage drawing at a draw ratio of 3.4 times using a liquid bath at a temperature of 90° C., tension heat-treated at a temperature of 140° C., and mechanical crimping with a crimper. It was applied, dried at a temperature of 120° C., and then cut into a length of 51 mm to obtain short fibers having a single fiber fineness of 2.2 dtex.

The short fibers obtained above are opened, a fibrous web is formed using a card, and after needle punching, heat treatment is performed at a temperature of 160° C. to obtain a nonwoven fabric having a basis weight of 100 g/cm ^2, and the nonwoven fabric properties are evaluated. In addition, the dyeability and the appearance of the non-woven fabric were confirmed by dyeing evaluation.

The obtained non-woven fabric was excellent in elasticity and capable of being subjected to disperse dye dyeing at a temperature of 95° C. in the dyeing step after the non-woven fabric was processed, and a high-quality non-woven fabric without wrinkles could be obtained. The results are shown in Table 1.

(Example 2)
A fiber was produced by the same method as in Example 1 except that the intrinsic viscosity of the atmospheric pressure disperse dye-dyeable polyester (A) was 0.75, and a nonwoven fabric was produced. The obtained non-woven fabric was excellent in elasticity and capable of being subjected to disperse dye dyeing at a temperature of 95° C. in the dyeing step after the non-woven fabric was processed, and a high-quality non-woven fabric without wrinkles could be obtained. The results are shown in Table 1.

(Example 3)
Except that the diol component having a side chain of 3 carbon chains is 5 mol% and the content of polyethylene glycol is 2% by mass with respect to the total diol component of the normal pressure disperse dye dyeable polyester (A). A fiber was produced in the same manner as in Example 1 to produce a nonwoven fabric. The obtained non-woven fabric was excellent in elasticity and capable of being subjected to disperse dye dyeing at a temperature of 95° C. in the dyeing step after the non-woven fabric was processed, and a high-quality non-woven fabric without wrinkles could be obtained. The results are shown in Table 1.

(Example 4)
Except that the diol component having a side chain of 3 carbon atoms is 10 mol% and the content of polyethylene glycol is 4% by mass with respect to the total diol component of the normal pressure disperse dye dyeable polyester (A). A fiber was produced in the same manner as in Example 1 to produce a nonwoven fabric. The obtained non-woven fabric was excellent in elasticity and capable of being subjected to disperse dye dyeing at a temperature of 95° C. in the dyeing step after the non-woven fabric was processed, and a high-quality non-woven fabric without wrinkles could be obtained. The results are shown in Table 1.

(Example 5)
A fiber was produced by the same method as in Example 1 except that the mass ratio of the normal pressure disperse dye-dyeable polyester (A) and the polyester (B) was (A)/(B)=60/40. Then, a non-woven fabric was manufactured. The obtained non-woven fabric was excellent in elasticity and capable of being subjected to disperse dye dyeing at a temperature of 95° C. in the dyeing step after the non-woven fabric was processed, and a high-quality non-woven fabric without wrinkles could be obtained. The results are shown in Table 1.

(Comparative Example 1)
Only the normal pressure disperse dye dyeable polyester (A) was melt-spun at a spinning temperature of 280° C. through a round hole spinneret having 350 discharge holes to obtain an undrawn yarn tow at a take-up speed of 1200 m/min. A fiber was produced in the same manner as in Example 1 to produce a nonwoven fabric. The obtained non-woven fabric was evaluated, but no stretchability was obtained. The results are shown in Table 2.

(Comparative example 2)
Except that the diol component having side chains of 3 carbon atoms is 12 mol% and the polyethylene glycol content is 1% by mass, based on the total diol component of the normal pressure disperse dye-dyeable polyester (A). A fiber was produced in the same manner as in Example 1 to produce a nonwoven fabric. The obtained non-woven fabric was evaluated, but sufficient dyeability could not be obtained. The results are shown in Table 2.

(Comparative example 3)
A nonwoven fabric was obtained by producing fibers in the same manner as in Example 1 except that the intrinsic viscosity of the polyester (B) was 0.65. The obtained non-woven fabric was evaluated, but the stretchability was insufficient. The results are shown in Table 2.

Claims (3)

The main repeating component is a polyester composed of ethylene terephthalate, the diol component having 3 side chains and 5 to 10 mol% of the side chains and the polyethylene glycol content of 2 to 4% by mass relative to the total diol component. And an atmospheric pressure disperse dye dyeable polyester (A), which is a polyester (A) having an intrinsic viscosity of 0.02 to 0.25 lower than that of the atmospheric pressure disperse dye dyeable polyester (A) and consisting essentially of ethylene phthalate units ( consists a B), a nonwoven fabric expressing reduced number tendon during the heat treatment under no load is with 40 U / 25mm or more der Ru latent resident crimped easily dyed polyester bicomponent fibers at a temperature of 180 ° C., the A non-woven fabric comprising the latently crimpable dyeable polyester conjugate fiber in an amount of 70% by mass or more, an elongation rate of 65% or more, and an elongation recovery rate of 60% or more . The non-woven fabric according to claim 1, wherein the polyester (A) dyeable with an atmospheric pressure disperse dye has an intrinsic viscosity of 0.52 to 0.80 and the polyester (B) has an intrinsic viscosity of 0.50 to 0.75. The non-woven fabric according to claim 1 or 2, wherein the composite ratio of the atmospheric pressure disperse dye dyeable polyester (A) and the polyester (B) is (A)/(B)=60/40 to 40/60 in terms of mass ratio.