JP5026041B2 - Polyester composite fiber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an antistatic agent causing no crack in the polyester as sheath component due to a post-processing such as alkali reduction even in case of being continuously charged in a long striated manner in polyester fibers, thus capable of exerting sufficient antistatic performance. <P>SOLUTION: A polyester composition with a relative viscosity of 2.8 or higher is provided, being such that 50-85 wt.% of a polyalkylene glycol 10,000 or higher in weight-average molecular weight and 10-40 wt.% of an organic metal sulfonate compound of the chemical formula 1 are compounded with each other so as to meet the relationship 1 the below, and the rest of the component consists of a polyester component. The chemical formula 1 is as follows: RSO<SB>3</SB>M (wherein, R is a &ge;6C alkyl, aryl or alkylaryl; and M is an alkali metal or alkaline earth metal atom). The relationship 1 is as follows: 80(wt.%)&le;(A+B)&le;95(wt.%) (wherein, A denotes the amount of a polyalkylene glycol component; and B denotes the amount of an organic metal sulfonate compound component). <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  Polyester fibers are widely used from the apparel to industrial materials due to their excellent properties. However, polyester fibers have a problem that they are easily charged with static electricity because of their high electrical resistance. In the clothing field, this causes discomfort such as a discharge phenomenon during attachment and detachment and clinging to the body, especially in winter. In order to improve the disadvantage that is easily charged with static electricity, modification of polyester fibers has been proposed with various antistatic agents.

  For example, as disclosed in JP-A-3-206120 and the like, a technique in which a polyester composition comprising a high molecular weight polyethylene glycol and an electrolyte is used as an antistatic agent for polyester fibers is well known. The electrolyte is an inorganic electrolyte such as an alkali metal or alkaline earth metal halogen compound, an alkali metal salt compound such as alkyl sulfonic acid, benzene sulfonic acid, alkyl benzene sulfonic acid, or 5-sulfoisophthalic acid, or an alkaline earth metal salt compound. However, organic electrolytes are generally used for reasons such as thread breakage due to foreign matters in the electrolyte.

  The antistatic agent as described above is continuously added in a long streak shape while being highly oriented in the fiber axis direction so that the polyester fiber exhibits excellent antistatic performance. For example, a core-sheath type composite polyester fiber having polyester as a sheath component and an antistatic agent as a core component is known. However, such a core-sheath type composite polyester fiber has a problem of causing a decrease in antistatic performance when post-processing such as alkali weight reduction is performed.

  According to JP 56-79717, fiber forming polymers such as polyethylene terephthalate and the antistatic composition as described above are different in tensile properties when solidified and oriented from the melted state during spinning, respectively. It is stated that the sheath component and the core component are distorted and are liable to crack.

  Furthermore, polyalkylene glycols typified by polyethylene glycol have extremely good compatibility with polyester polymers, so when bonded in a molten state at high temperature during spinning, the sheath component side is at the interface between the core component and the sheath component. Easy to move distributed. Even when solidified and oriented in such a portion, the physical properties of the fiber are lowered, and partial cracks are likely to occur.

  Such cracks are likely to occur particularly after severe processing steps such as alkali weight loss, and there arises a problem that the antistatic performance is lowered due to the dissolution of the antistatic component simultaneously with the cracks.

Japanese Patent Laid-Open No. 3-206120 Japanese Unexamined Patent Publication No. 56-79717

It is an object of the present invention to obtain a polyester composite fiber capable of exhibiting sufficient antistatic performance without cracking in the polyester of the sheath component by post-processing such as alkali weight loss even when continuously fed into the polyester fiber in a long streak shape And

  In view of the above problems, the present inventor has intensively studied the appropriate selection of polyalkylene glycol and the blending ratio of the organic sulfonic acid metal salt and the viscosity of the antistatic agent itself. The present invention has been completed by finding an antistatic agent that is difficult and does not crack even when the amount of alkali is reduced.

That is, the present invention includes a range of 50 to 85% by weight of a polyalkylene glycol having a weight average molecular weight of 16000 or more and 10 to 40% by weight of an organic sulfonic acid metal salt compound represented by the following chemical formula 1 in the total weight of the composition. The polyester composite fiber, which is blended so as to satisfy the following formula 1 and the remaining component is a polyester component and the relative viscosity of which is 2.8 or more, is arranged after the core weight loss, etc. It is characterized by stable and good antistatic performance even after processing.
RSO ₃ M (Chemical formula 1)
[R represents an alkyl group having 6 or more carbon atoms, an aryl group, or an alkylaryl group, and M represents an alkali metal or an alkaline earth metal]
80 ≦ (A + B) ≦ 95 (Formula 1)
[A is a polyalkylene glycol component, B is an organic sulfonic acid metal compound component, and all units are by weight (composition)]

  The polyester fiber containing the composition of the present invention as a core component exhibits good antistatic performance and does not crack even when alkali weight reduction is performed. Therefore, the antistatic performance does not deteriorate, and good performance can be stably exhibited.

Specific examples of the polyalkylene glycol used in the present invention include polyethylene glycol, polymethylene glycol, and polypropylene glycol. Although the weight-average molecular weight is not particularly limited as long as 1 6 000 or more, it is preferable to use a polyethylene glycol due to its flexibility.

Polyalkylene glycols used in the present invention, a weight average molecular weight of 1 6 000 or more. If the weight average molecular weight is less than 1 6 000, when added to polyester fiber as the antistatic agent by melting the polyester composition, easily dispersed into the polyester fibers, cracks are likely to occur. The weight average molecular weight is particularly preferably 18000 or more.

  Moreover, it is necessary to mix | blend this polyalkylene glycol so that it may become 50 to 85 weight% with respect to 100 weight% of compositions. In the case of less than 50% by weight, in order to obtain sufficient antistatic performance, it is necessary to add more than 40% by weight of the organic sulfonic acid metal salt compound described later. When more is blended, the composition cannot be polymerized to a relative viscosity of 2.8 or more.

  Further, when the blending amount is more than 85% by weight, the composition ratio of the polyester component is less than 5% by weight, so that the composition cannot be polymerized to a relative viscosity of 2.8 or more. A preferable addition rate is 60 to 80%, and 60 to 75% is particularly preferable.

  As the organic sulfonic acid metal salt compound in the present invention, an alkylsulfonic acid, an alkylarylsulfonic acid, or an alkali metal salt or alkaline earth metal salt of an arylsulfonic acid can be used. Has 6 or more carbon atoms. In the present invention, among organic sulfonic acid metal compounds satisfying the above conditions, sodium dodecylbenzenesulfonate (DBS) is preferably used because of its versatility.

  The organic sulfonic acid metal salt compound needs to be blended so as to be 10 to 40% by weight with respect to 100% by weight of the polyester composition, preferably 15 to 30%, and particularly preferably 15 to 25%. If it is less than 10% by weight, sufficient antistatic performance cannot be obtained.

  The total amount of the polyalkylene glycol and the organic sulfonic acid metal salt compound must be 80% by weight to 95% by weight with respect to 100% by weight of the polyester composition. When the amount is less than 80% by weight, sufficient antistatic performance cannot be obtained, and when it is more than 95% by weight, the composition cannot be polymerized to a relative viscosity of 2.8 or more.

  The polyester component used in the present invention can be obtained by polymerizing an aromatic dicarboxylic acid component and a glycol component by a conventional method. Most preferred is polyethylene terephthalate.

  The relative viscosity of the polyester composition of the present invention needs to be 2.8 or more, preferably 3.0 or more, and particularly preferably 3.2 or more. When the relative viscosity is less than 2.8, the strain increases between the core component as the antistatic agent and the polyester fiber as the sheath component, and cracks are likely to occur.

  In the present invention, various known additives may be appropriately added. For example, silicon dioxide or the like may be added for the purpose of improving production efficiency. Further, for the purpose of improving the thermal stability, an antioxidant or the like may be added and blended.

  The production method of the polyester composition of the present invention will be described with an example. Polyethylene glycol having a predetermined molecular weight range as polyalkylene glycol, sodium dodecylbenzenesulfonate (65% by weight aqueous solution) as organic sulfonic acid metal salt compound, bis-α-hydroxyethyl terephthalate (hereinafter referred to as BHET) as a polyester component, polymerization reaction The raw material is niantimony trioxide as a catalyst. These specified amounts are put into a reaction vessel and heated to 235 ° C. while removing the distilled water, and stirred for about 1 hour after complete dissolution. After confirming that the specified amount of water has been removed, the internal pressure is reduced to 133 Pa or less with a vacuum pump, and a polymerization reaction is carried out at 250 ° C. to obtain the desired polyester composition.

  A method for producing antistatic fibers using the polyester composition of the present invention will be described with an example. The composition obtained above is quantitatively fed by a gear pump in a molten state at 180 ° C., appropriately filtered, and then fed to a composite spinneret. The composite spinneret is not particularly limited as long as the flow path is designed so that two kinds of polymers have a core-sheath structure. The filaments are spun so that the molten composition is placed on the core at a mixing ratio of 1-2% by weight in the fiber.

  The polyester composition of the present invention is optimal for use as a raw material for antistatic fibers by such a method. As the material of the antistatic fiber, any material that can be melt-spun such as polyester, polyamide, and polyolefin can be used. However, the polyester composition of the present invention exerts its effect remarkably in a composite fiber with polyester, particularly polyethylene terephthalate.

  The antistatic fiber obtained as described above has antistatic performance without causing cracks even when alkali weight reduction processing is performed, and without impairing the quality of the fabric. In particular, it can be suitably used for clothing linings that require high quality as a fabric in thin fabrics.

Hereinafter, the present invention will be described in detail with reference to examples.
Each characteristic value in the examples was determined according to the following method.
[Relative Viscosity] 0.5 g of the polyester composition was dissolved in 50 ml of a phenol / tetrachloroethane = 6/4 (mass ratio) mixture and measured at 20 ° C. using an Ostwald viscometer.
[Intrinsic viscosity] The intrinsic viscosity was calculated from the calculated relative viscosity according to the following formula.
[Intrinsic viscosity] = (√ (1 + 1.48 × [relative viscosity]) − 1) /0.74
[Antistatic performance] After weaving the taffeta under the following conditions and performing alkali weight reduction processing, the charged voltage (kV) was measured according to the triboelectric discharge curve measurement method which is a reference method of JIS L1094 (1988), and after 60 seconds The voltage (kV) was described as the friction band voltage. The time (seconds) until the charged voltage was halved was evaluated as the half-life.
[Alkali Weight Loss Resistance] Using the same sample as that for measuring the antistatic performance, the presence or absence of cracks in the sheath component was confirmed by observation with an electron microscope. In the table, a case where a crack was observed was indicated as “crack”, and a case where a crack was not observed was indicated as “◯”.

Example 1
Polyethylene glycol having a weight average of 18000, a 65% aqueous solution of sodium dodecylbenzenesulfonate, BHET, niantimony trioxide and Irganox 1010 as a polymerization catalyst were added, and a polymerization reaction was performed in a 1 L flask to obtain a polyester composition. The composition and relative viscosity of the obtained polyester composition are shown in Table 1.

  Using the polyester composition as a core component, polyethylene terephthalate having an intrinsic viscosity of 0.63 as a sheath component, using a core-sheath composite spinneret, melt spinning is performed at 290 ° C. to obtain a 56 dtex / 36 filament (f) polyester filament. Obtained. The core-sheath ratio of this polyester filament is as having shown in the table | surface as fiber press-fit amount (weight% / fiber).

  The polyester filament was used as a warp, and a normal polyester yarn of 84 dtex / 36f was used as a weft to be woven. The polyester taffeta obtained was subjected to a weight reduction process of 98 ° C. × 40 minutes with a 4% aqueous sodium hydroxide solution, and then the frictional voltage was measured. In addition, the durability and resistance to alkali weight loss processing were confirmed by observing the surface and cross section of the yarn with an electron microscope. The results are shown in Table 1.

(Example 2)
Polymerization and spinning were carried out in the same manner as in Example 1 except that the composition amounts of polyethylene glycol having a weight average molecular weight of 18000, 65% aqueous solution of sodium dodecylbenzenesulfonate and BHET were changed, and polyester filaments were evaluated. The results are shown in Table 1.

(Comparative Example 1)
Polymerization and spinning were carried out with the same composition as in Example 2 except that the weight average molecular weight of polyethylene glycol was 6000, and polyester filaments were evaluated. The results are shown in Table 1.

(Comparative Example 2)
Polymerization and spinning were carried out in the same manner as in Example 1 except that the composition amount of polyethylene glycol having an average molecular weight of 18000 was 30% by weight, and the composition amount of BHET was changed accordingly, and polyester filaments were evaluated. The results are shown in Table 1.

(Comparative Example 3)
Polymerization was carried out with the same composition as in Example 1, but the polymerization reaction time was adjusted to obtain a polyester composition having a relative viscosity of 2.0. Using this, spinning was carried out in the same manner as in Example 1, and polyester filaments were evaluated.

The polyester composition of the present invention can be used in various applications as an antistatic agent. In particular, an antistatic yarn excellent in processing durability can be obtained by using it as an antistatic component of a composite polyester filament.

Claims (4)

In the total weight of the composition, the polyalkylene glycol having a weight average molecular weight of 16000 or more satisfies 50 to 85% by weight, and the organic sulfonic acid metal salt compound represented by the following chemical formula 1 satisfies 10 to 40% by weight. A polyester composite fiber in which a polyester composition having a relative viscosity of 2.8 or more, in which the remaining components are composed of a polyester component, is disposed as a core .
RSO ₃ M (Chemical formula 1)
[R represents an alkyl group having 6 or more carbon atoms, an aryl group, or an alkylaryl group, and M represents an alkali metal or an alkaline earth metal]
80 ≦ (A + B) ≦ 95 (Formula 1)
[A is a polyalkylene glycol component, B is an organic sulfonic acid metal compound component, and all units are by weight (composition)] The polyester composite fiber according to claim 1, wherein the polyalkylene glycol is polyethylene glycol. The polyester composite fiber according to claim 1, wherein the organic sulfonic acid metal salt compound represented by Chemical Formula 1 is sodium dodecylbenzenesulfonate. The polyester composite fiber according to claim 1 , wherein the polyester component of the polyester composition is polyethylene terephthalate.