JP2867582B2 - Composite fiber - Google Patents

Description

The present invention relates to a conjugate fiber. More specifically, the present invention relates to a conjugate fiber which contains a readily hydrolyzable polyester blend as one component and can easily obtain a microfiber or a specially shaped cross-section yarn by alkali hydrolysis.

(Prior art) Conventionally, as a method for producing ultrafine fibers, the direct spinning method is extremely difficult in terms of operability during spinning / drawing, yarn quality of ultrafine yarn, and handling up to a higher processing stage. It is often difficult in terms of nature and cost. For this reason, a means for dissolving and removing one component occupying at least a part of the fiber surface or swelling and splitting is used after forming a composite fiber of a different component (sea-section type, blend type, splittable multilayer type, etc.). I came.

In particular, the ultra-fine fibers of polyamide or polyester obtained by dissolving and removing one component can be ultra-fine in the point of uniform dyeing and after fabricating. It is advantageous from the point. For this reason, when producing ultrafine fibers consisting only of polyamide or polyester, it is necessary to use a polymer having a solubility and a dissolution rate difference from the components left as elution components.

Conventionally, polystyrene or polyethylene, which is soluble in polyamide or polyester, has been used as an elution component as a means for obtaining ultrafine fibers of polyamide or polyester. In some cases, a copolymerized polyester obtained by copolymerizing a second component or a third component with a polyester to make it soluble or easily eluted is used.

(Problems to be Solved by the Invention) When polystyrene or polyethylene is used to obtain ultrafine fibers of polyamide or polyester, a chlorinated solvent such as trichlene or pearlene is required as the solvent, but from the viewpoint of pollution and safety. Significant costs are required for collection and processing equipment.

In addition, when the copolymer polyester is used, when the alkali is eluted, there is no problem when the island component is a polymer insoluble in the alkali elution such as nylon 6, but when the component is eroded by an alkali solution such as polyethylene terephthalate. Since the elution rate difference is insufficient, the elution of the sea component is incomplete, or if the conditions are set to the complete elution, a part of the island component is also eluted, and the purpose cannot be achieved. It is conceivable to increase the copolymerization ratio of the second component to increase the alkali elution rate, but this not only increases the cost but also lowers the heat resistance and deteriorates the spinnability. In addition, there is a proposal to use a copolymerized polyester which can be eluted only with boiling water as a sea component by copolymerizing the third component to increase the dissolution rate. However, there are problems such as difficulty in forming chips during polymerization and an increase in chemical cast.

Means for Solving the Problems In view of the above problems, the present inventors have conducted intensive studies and have arrived at the present invention.

(Means for Solving the Problems) That is, the conjugate fiber of the present invention is a conjugate fiber composed of at least two components, wherein at least one component of the conjugate fiber is a polyester, and the polyester is 80 mol% or more of alkylene terephthalate. It has a repeating unit, and 5 mol% or less of the total acid component is a sulfonic acid metal base-containing carboxylic acid component, and a glycol component represented by the following general formula [I]
Characterized in that it is a readily hydrolyzable copolymerized polyester containing from 1 to 10% by weight of a glycol based on the polymer, and a blend of the polyester containing from 2 to 30% by weight of a polyalkylene glycol. .

HO- in _{(C i H 2i O) m} R-O- (C j H 2j O) n H (I) (wherein, R is a divalent aliphatic hydrocarbon group or an aromatic 4 to 20 carbon atoms carbide Hydrogen groups, i and j are the same or different
The positive integers 4 and m and n are the same or different 0 or positive integers, and 1 ≦ (m + n) ≦ 15. The conjugate fiber in the present invention refers to an ultrafine fiber-generating conjugate fiber obtained by removing one component or a conjugate fiber that forms various deformed cross sections by removing one component.

In the alkali easily hydrolyzable polyester which is one component of the conjugate fiber of the present invention, 5 mol% or less of the total acid component is a sulfonic acid metal base-containing carboxylic acid component, and 1 to 10% by weight of the produced polyester. It is a polyester which is a glycol represented by the following general formula [I], and is a polyester blend in which 2 to 30% by weight of a polyalkylene glycol is blended with the polyester.

HO- in _{(C i H 2i O) m} R-O- (C j H 2j O) n H (I) (wherein, R is a divalent aliphatic hydrocarbon group or an aromatic 4 to 20 carbon atoms carbide Hydrogen groups, i and j are the same or different
The positive integers 4 and m and n are the same or different 0 or positive integers, and 1 ≦ (m + n) ≦ 15. HO-R-OH wherein m and n are both 0 in the general formula [I]
In the case of glycol or a modified glycol mixture in which the average value of m + n is smaller than 1, there is a problem that it distills out during polymerization and the melting point of the obtained polyester is lowered. When m + n exceeds 15, the light resistance is lowered, which is not preferable because it includes a problematic element. When the content of the glycol is less than 1% by weight, the alkali hydrolytic ability is not sufficient, and when it exceeds 10% by weight, the melting point of the polymer is remarkably lowered, which is problematic. The sulfonic acid metal base-containing carboxylic acid component present is preferably 0.5 to 5.0 mol% of the total acid component, particularly 1.0 to 3.5 mol% of the total acid component, and more preferably 1.0 to 2.0 mol%. preferable. 0.5 mol%
If it is less than 5%, the hydrolytic capacity becomes insufficient, and if it exceeds 5 mol%, single yarn breakage and back pressure of the nozzle become large during spinning, and the operability decreases.

In addition, it is necessary to blend 2 to 30% by weight of the polyalkylene glycol to the copolymerized polyester. The polyalkylene glycol referred to here can be, for example, polyethylene glycol, polypropylene glycol, or a random or block copolymer of ethylene oxide and propylene oxide. The polyalkylene glycol is selectively eluted to form micro concaves in the eluted component, resulting in a remarkable increase in the surface area. As a result, the effect of increasing the alkali elution rate is utilized. Although it is not a substance, it has a molecular weight of 10 in terms of heat resistance and measurement in the molten state.
Polyethylene glycol of 000 to 20,000 is preferable, and the blending amount is required to be at least 2% by weight or more to achieve the intended purpose. If the blending amount exceeds 30% by weight, the viscosity of the blend is remarkably reduced, and Performance is impaired.

Preferably 5 to 20% by weight, more preferably 5 to 10% by weight
Just blend.

If desired, various additives such as an oxidation stabilizer, an ultraviolet absorber, a flame retardant, inorganic particles, and an antistatic agent may be added to the copolymerized polyester.

A composite yarn is made using the above polymer. Examples of the polymer to be a composite partner include polyamides such as nylon 4, nylon 6, nylon 7, nylon 11, nylon 12, and nylon 66; polyesters such as polyethylene terephthalate and polybutylene terephthalate; polyethylene;
Polyolefins such as polypropylene, and copolymers and modified products of these can be used as long as they can be melt-spun. Polyester yarns whose alkali dissolution rate after stretching is 100% polyethylene terephthalate and whose intrinsic dissolution viscosity is 0.63 It must be within 3 times the alkali elution rate. In particular, polyethylene terephthalate, nylon 6,
Alternatively, it has an alkylene terephthalate repeating unit of 80 mol% or more, and 0.5 to 1.5 mol% of the total acid component is a sulfonic acid metal base-containing carboxylic acid component, and is represented by the following general formula [I] HO- (C _{i H 2i O) m R-} O- (C j H 2j O) n H (I) (wherein, R is a divalent aliphatic hydrocarbon group or an aromatic hydrocarbon group having 4-20 carbon atoms, i , J are the same or different 2
The positive integers 4 and m and n are the same or different 0 or positive integers, and 1 ≦ (m + n) ≦ 15. A cationically dyeable, hardly decomposable copolymerized polyester containing 3 to 5% by weight of the glycol represented by the formula (1) above the glycol component of the polymer blended with the polyalkylene glycol is preferred. The alkali elution rate is 60 g at 90 ° C with a 30 g / l aqueous solution of sodium hydroxide.
The weight loss rate determined from the fabric weight after drying is 60
Divide by the alkali elution rate (% / min). However, in the case of a substance having a high alkali elution rate such that 100% is eluted under the above conditions, the treatment is performed under the same conditions for only about 50% elution time, and the weight loss rate at that time is divided by the processing time, and the alkali elution rate (% / min) ). The composite form is not particularly limited, and is generally referred to as a sea-island type (polymer array fiber: in this case, a copolymerized polyester blend is used for the sea component:
(Fig. 1), radial type (Fig. 2), multiple bonding type (Fig. 3)
Figure), sunflower type (Figure 4), etc. can be arbitrarily selected.

(Examples) Examples 1 to 4 and Comparative Examples 1 to 4 Four types of polymers [A], [B], [C] and [D] were polymerized under the following conditions.

Polymer [A] dimethyl terephthalate (DMT) 1000 parts, 5-sodium sulfoisophthalic acid dimethyl ester (DSN) 45.8
Part, 700 parts of ethylene glycol (EG) and R in the general formula [I] are 2,2-dimethylpropylene groups and j,
In a transesterification reactor, 45.3 parts of glycol in which j is 2 and the value of m + n is 5 are added to a zinc acetate dihydrate of 0.1 part.
38 parts, 0.50 parts of sodium acetate (0 parts when DSN is not added) and 0.33 parts of antimony trioxide
The transesterification reaction was performed while evaporating by-product methanol while elevating the temperature to 150 to 210 ° C. over 130 minutes. Further, diethyl-2-carbethoxyethylphosphonate 0.8
And held for 10 minutes. 210 ° C.
The system is gradually depressurized while the internal temperature is raised to 210 to 275 ° C in 80 minutes, and then the polycondensation reaction is carried out at 275 ° C and 0.1 mmHg for about 40 minutes to obtain a mixture having a predetermined composition. A polymerized polyester was obtained. The intrinsic viscosity of the obtained polymer (measured in a solvent of phenol / tetrachloroethane = 6/4 at 30 ° C.) is 0.46.
Met.

Polymer [B] Only 1,000 parts of dimethyl terephthalate (DMT), 700 parts of ethylene glycol (EG), and 0.33 part of antimony trioxide are charged into a transesterification reactor, and polymerized in the same manner as in the case of polymer [A]. Thus, a polyester resin was obtained. The intrinsic viscosity of the polymer was 0.63.

Polymer [C] 1000 parts of dimethyl terephthalate (DMT), dimethyl 5-sodium sulfoisophthalate (DSN) 45.8
, 700 parts of ethylene glycol (EG) and 0.33 parts of antimony trioxide, and the ester exchange reaction was performed while evaporating the by-product methanol while elevating the temperature to 150 to 210 ° C over 130 minutes. . Further, 0.8 parts of diethyl-2-carbethoxyethylphosphonate was added and the mixture was kept for 10 minutes. The obtained product was transferred to a 210 ° C. polycondensation canister, and while the internal temperature was being raised to 210 ° C. to 275 ° C. for 80 minutes, the system was gradually reduced in pressure.Then, the polycondensation reaction was performed at 275 ° C. 0.1 mmHg. This was carried out for about 40 minutes to obtain a copolymerized polyester having a predetermined composition. The intrinsic viscosity of the obtained polymer (measured with a phenol / tetrachloroethane = 6/4 solvent at 30 ° C.) was 0.48.

Polymer [D] dimethyl terephthalate (DMT) 1000 parts, 5-sodium sulfoisophthalic acid dimethyl ester (DSN) 19.9
Part, 700 parts of ethylene glycol (EG) and R in the general formula [I] are 2,2-dimethylpropylene groups and i,
60.4 parts of glycol in which j is 2 and m + n value is 5 are placed in a transesterification reactor, and this is added to zinc acetate dihydrate (0.1%).
38 parts, sodium acetate 0.50 parts and antimony trioxide 0.
33 parts were added and transesterification was performed while evaporating methanol as a by-product while elevating the temperature to 150 to 210 ° C. over 130 minutes. Further, 0.8 parts of diethyl-2-carbethoxyethylphosphonate was added and the mixture was kept for 10 minutes. The obtained product was transferred to a polycondensation can at 210 ° C., and the internal temperature was reduced to 210 to 80 minutes.
While raising the temperature to 275 ° C, the system was gradually depressurized, and then 275 ° C at 0.
A polycondensation reaction was performed at 1 mmHg for about 40 minutes to obtain a copolymerized polyester having a predetermined composition. The intrinsic viscosity of the obtained polymer (measured with a solvent of phenol / tetrachloroethane = 6/4 at 30 ° C.) was 0.60.

Polymer [E] 1000 parts of dimethyl terephthalate (DMT), 5-sodium sulfoisophthalic acid dimethyl ester (DSN) 84.2
Part, 700 parts of ethylene glycol (EG) and R in the general formula [I] are 2,2-dimethylpropene groups and i,
In a transesterification reactor, 45.3 parts of glycol in which j is 2 and the value of m + n is 5 are added to a zinc acetate dihydrate of 0.1 part.
38 parts, sodium acetate 0.50 parts and antimony trioxide 0.
33 parts were added and transesterification was performed while evaporating methanol as a by-product while elevating the temperature to 150 to 210 ° C. over 130 minutes. Further, 0.8 parts of diethyl-2-carbethoxyethylphosphonate was added and the mixture was kept for 10 minutes. The obtained product was transferred to a polycondensation can at 210 ° C., and the internal temperature was reduced to 210 to 80 minutes.
While raising the temperature to 275 ° C, the system was gradually depressurized, and then 275 ° C at 0.
A polycondensation reaction was performed at 1 mmHg for about 40 minutes to obtain a copolymerized polyester having a predetermined composition. The intrinsic viscosity of the obtained polymer (measured with a solvent of phenol / tetrachloroethane = 6/4 at 30 ° C.) was 0.60.

(Polyethylene glycol blend) The polyester to be blended is 0.1mmHg, 130 ℃
After cooling for 12 hours or more and cooling at 0.1 mmHg at 25 ° C., a predetermined amount of polyethylene glycol having a molecular weight of 20,000 (hereinafter abbreviated as PEG) is blended and pelletized at 280 ° C. with a kneader having two screws. Used. Hereinafter, the blending amount of PEG is represented by% by weight based on the base polymer.

(Judgment of morphology after elution) After the yarn after elution is embedded in an acrylic resin and solidified, cut with a microtome to obtain a flake, and the resin is eluted with isoamyl acetate. The sample was taken at 5 times at 5,000 times with a scanning electron microscope and judged.

The content of the 5-sodium sulfoisophthalic acid component (GCM) in each of the polymers [A] to [E] and the neopentyl glycol ethylene oxide adduct component (GD
Table 1 shows the content of M). In addition, polymer [A]
Tables 2 to 4 show the results of composite spinning using [E] and elution with alkali.

(Effects of the Invention) According to the present invention, it has become possible to obtain a conjugate fiber that can be easily desealed with almost no elution of island components.

[Brief description of the drawings]

1 to 4 are cross-sectional views of the conjugate fiber according to the present invention. A indicates an eluted component, and B indicates a residual component.

Claims (1)

(57) [Claims] 1. A conjugate fiber comprising at least two components, wherein at least one component of the conjugate fiber is a polyester, the polyester has 80 mol% or more of alkylene terephthalate repeating units, and 5 mol of a total acid component. % Or less is a sulfonic acid metal base-containing carboxylic acid component, and is a readily alkali-hydrolyzable copolymerized polyester containing from 1 to 10% by weight of a glycol represented by the following general formula [I] as a glycol component, and A conjugate fiber comprising a blend of the polyester containing 2 to 30% by weight of polyalkylglycol. HO- in _{(C i H 2i O) m} R-O- (C j H 2j O) n H (I) (wherein, R is a divalent aliphatic hydrocarbon group or an aromatic 4 to 20 carbon atoms carbide Hydrogen groups, i and j are the same or different
The positive integers 4 and m and n are the same or different 0 or positive integers, and 1 ≦ (m + n) ≦ 15. )