JP2006028645A - Ultra fine yarn - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polytrimethylene terephthalate ultra fine yarn which can give high density woven or knitted fabrics having soft touch, fine touch and colorability that have been achieved by conventional techniques, can be produced in excellent productivity, and gives waste liquids giving small environmental loads, after treated with an alkali. <P>SOLUTION: The ultra fine yarn comprising a yarn substantially composed from polytrimethylene terephthalate is characterized in that a dry heat shrinkage rate (TWA) after an alkali reduction and a single fiber fineness (FDT) after an alkali reduction satisfy all of expression (1): 5≤TWA(%)≤20, and expression (2): 0.01≤FDT(dtex)≤1. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an ultrafine yarn having a high shrinkage characteristic, more specifically, excellent in spinning stability, can obtain an unprecedented high-density woven or knitted fabric, and imparts excellent fineness, softness and color development. The present invention relates to an ultrafine yarn that can be used.

  Conventionally, polyester extra fine yarns having a single yarn fineness of 1 dtex or less made of polyethylene terephthalate have been used in peach-woven fabrics and wiping cloths. However, since the shrinkage characteristics of conventional ultrafine yarn are insufficient, the feeling of fluffiness cannot be eliminated when it is made into a woven or knitted fabric, and the feeling of precision is poor. For this reason, extra fine yarns using polytrimethylene terephthalate (polypropylene terephthalate) whose polymer itself has high shrinkage properties are disclosed in Japanese Patent Application Laid-Open No. 11-1000072 (Patent Document 1) and Japanese Patent Application Laid-Open No. 2001-348735 (Patent). It is proposed in the literature 2). Certainly, since the single yarn fineness is thin, a soft woven or knitted fabric can be obtained. However, with these yarns, the density of the woven or knitted fabric cannot be increased, and a smooth woven or knitted fabric with a fine feeling cannot be obtained.

  That is, the former is not an ultra-fine yarn obtained from the sea-island type composite yarn, but is a direct spinning type, so there is a problem of delayed shrinkage in the take-up package and the raw machine, and the yarn must be reduced in the drawing process. .

For the latter, ultrafine yarn is obtained from sea-island type composite yarn, but the polymer used as the alkali elution component is a polyester copolymerized with an organic metal salt, and the alkali elution time is long. There is a problem that the polytrimethylene terephthalate component is prevented from shrinking. Furthermore, since the alkali elution time is long, the productivity is poor, and the polymer melting temperature is higher than that of polytrimethylene terephthalate, so it is necessary to keep the spinning temperature high, which causes the thermal degradation of polytrimethylene terephthalate to progress. There are problems such as poor operability and satisfactory raw yarn strength and texture cannot be obtained.
Japanese Patent Application Laid-Open No. 11-100721 JP 2001-348735 A

  The present invention makes it possible to obtain a high-density woven or knitted fabric excellent in softness, precision, and colorability, which is not achieved with the above-described conventional technology, and is excellent in productivity, and the environmental impact of waste liquid after alkali treatment is small. It is to provide a polytrimethylene terephthalate ultrafine yarn.

  The ultrafine yarn of the present invention that achieves the above-described object has the following configuration.

An ultrafine yarn comprising a yarn substantially composed of polytrimethylene terephthalate, and having a dry heat shrinkage rate (TWA) and a single fiber fineness (FDT) satisfying all of the following formulas.
(1) 5 ≦ TWA (%) ≦ 20
(2) 0.01 ≦ FDT (dtex) ≦ 1
The ultrafine yarn of the present invention is preferably a sea-island type composite yarn in which the island component is composed of polytrimethylene terephthalate and sea component polylactic acid, and the sea component / island component composite ratio is 10/90 to 50/50.

  In the ultrafine yarn of the present invention, preferably, the boiling water shrinkage (SWA) and the dry heat shrinkage (TWA) after alkali weight reduction satisfy TWA (%) / SWA (%) ≧ 1. Is.

  In the ultrathin yarn of the present invention, the sea-island type composite yarn before alkali weight reduction preferably has a raw yarn strength of 3.0 cN / dtex or more.

  Moreover, the high-density fabric of the present invention is characterized by using the above-mentioned ultrafine yarn for warp and / or weft.

  According to the present invention, it is possible to obtain a polytrimethylene terephthalate extra fine yarn that can obtain a high-density woven or knitted fabric excellent in softness, fineness, and color development, is excellent in productivity, and has a low environmental impact due to waste liquid after alkali treatment. Provided. Moreover, even if it is a high-density woven or knitted fabric, stretchability can be imparted to the fabric.

  Furthermore, it is compatible with cellulosic fibers such as cotton, and is suitable for fabrication such as union with cotton.

  The cloth made of the ultrafine yarn of the present invention is used for clothing, particularly women's clothing such as dresses, shirts, blouses, skirts, and sports clothing such as raincoats, athletic wear, ski wear, etc. For clothing materials, it is suitable for handkerchiefs, wiping glasses, face wash towels, light-shielding curtains, and the like.

  Hereinafter, the present invention will be described in more detail.

  The extra fine yarn of the present invention is an extra fine yarn composed of a yarn substantially composed of polytrimethylene terephthalate.

It is important that the ultrafine yarn of the present invention has a dry heat shrinkage rate (TWA) satisfying the following formula (1).
(1) 5 ≦ TWA (%) ≦ 20
When ultrafine yarn is obtained by reducing the alkali, generally, the dry heat shrinkage is generally defined by the dry heat shrinkage before reducing the alkali. Alkali weight loss is used to create a soft and supple texture by melting the fiber surface to create voids at the intersections in the woven or knitted fabric. However, in high-density woven and knitted fabrics, it has been a problem that a feeling of fluffiness is also imparted by performing alkali weight reduction. In the present invention, as a result of intensive studies, it has been found that an ultrafine yarn capable of obtaining a soft and precise high-density woven or knitted fabric can be obtained by imparting shrinkage to the yarn even after alkali weight reduction. That is, when the dry heat shrinkage (TWA) of the yarn constituting the woven fabric after reducing the alkali satisfies 5 ≦ TWA (%) ≦ 20, a soft and precise high-density woven or knitted fabric can be obtained. When TWA (%) <5, it is impossible to impart a fine feeling to the woven fabric, and when TWA (%)> 20, the shrinkage is too strong and the coarseness of the woven fabric becomes strong. More preferably, 8 ≦ TWA (%) ≦ 20.

  In addition, the dry heat shrinkage rate (TWA) in this invention means the value measured with the measuring method mentioned later.

  Moreover, it is preferable that the ratio of the boiling water shrinkage (SWA) and the dry heat shrinkage (TWA) of the ultrafine yarn of the present invention satisfies TWA (%) / SWA (%) ≧ 1. This is because even if the dry heat shrinkage rate (TWA) is a high value, if the boiling water shrinkage rate (SWA) is higher than that, the soft and supple texture is reduced. More preferably, TWA (%) / SWA (%) ≧ 1.5.

  In addition, the boiling shrinkage rate (SWA) in this invention means the value measured with the measuring method mentioned later.

    In the present invention, the preferable range of the boiling water shrinkage (SWA) is 2 ≦ SWA (%) ≦ 15, more preferably 2 ≦ SWA (%) ≦ 10 in consideration of the processability of the dyeing process.

Furthermore, the single fiber fineness (FDT) of the ultrafine yarn of the present invention must satisfy the following formula (2).
(2) 0.01 ≦ FDT (dtex) ≦ 1
By satisfying 0.01 ≦ FDT (dtex) ≦ 1, it is possible to obtain a soft feeling when a woven or knitted fabric is formed. A more preferable range is 0.01 ≦ FDT (dtex) ≦ 0.5. When FDT (dtex)> 1, a soft feeling cannot be imparted to the woven or knitted fabric. On the other hand, if FDT (dtex) <0.01, it is too thin and the color developability deteriorates.

  Further, the cross-sectional shape of the ultrafine yarn may be an irregular cross-section such as a flat shape, a triangular shape, and a hollow shape in addition to a round cross-section.

    By making the extra fine yarn of the present invention into a woven fabric using warp yarn and / or weft yarn, it is possible to obtain a soft, high-density woven or knitted fabric with a fine feeling.

  The ultrafine yarn of the present invention is preferably obtained by alkali-reducing a sea-island type composite yarn in which the island component is composed of polytrimethylene terephthalate and the sea component polylactic acid. Such a sea-island type composite yarn eliminates the problem of processing such as delayed shrinkage in the state of the yarn package or the raw machine. In addition, since the sea component polylactic acid has a high alkali weight loss rate, it is easily dissolved in the alkali weight loss process, and the island component polytrimethylene terephthalate, that is, polytrimethylene terephthalate ultrafine yarn, is more likely to shrink.

  Polylactic acid has a lower melting temperature than polytrimethylene terephthalate or polyethylene terephthalate, so the spinning temperature is higher than when polyethylene terephthalate copolymerized with an organometallic salt whose melting temperature is higher than that of polytrimethylene terephthalate is used as the sea component. Can be kept low, and it is possible to stabilize operations including raw yarns and higher orders and to prevent a decrease in texture due to thermal degradation of polytrimethylene terephthalate. Due to the effects of these polylactic acids, it is possible to obtain a sea-island type composite yarn having a high raw yarn strength, a good yarn forming property, stretchability, good splitting property, excellent texture, and a small environmental load.

  The polylactic acid referred to in the present invention is not particularly limited, but is preferably a polylactic acid composed of L-lactic acid having an average molecular weight of 50,000 to 100,000 and a purity of 95.0% to 99.5%. In addition to being able to maintain strength in the process, moderate biodegradability can be obtained, so that the environmental load of the waste liquid after elution is small and preferable.

  In addition, when the sea component is polyethylene terephthalate, it takes time to completely dissolve with alkali weight reduction alone, and it is usually necessary to perform acid treatment such as maleic acid before weight loss with alkali. Although it could not be combined with fiber, the above problem can be solved by using polylactic acid as the sea component, and fabrication such as union with cotton becomes possible.

  The island component polytrimethylene terephthalate is a polyester obtained using terephthalic acid as the main acid component and 1,3 propanediol as the main glycol component. However, it may contain a copolymer component capable of forming another ester bond at a ratio of 20 mol% or less, preferably 10 mol% or less. Examples of copolymerizable compounds include dicarboxylic acids such as isophthalic acid, cyclohexanedicarboxylic acid, adipic acid, dimer acid, and sebacic acid, while glycol components include, for example, ethylene glycol, diethylene glycol, butanediol, neopentyl glycol, and cyclohexanedimethanol. , Polyethylene glycol, polypropylene glycol and the like can be mentioned, but are not limited thereto. Further, titanium dioxide as a matting agent, silica or alumina fine particles as a lubricant, hindered phenol derivatives, coloring pigments and the like as antioxidants can be added as necessary.

  The ultrafine yarn of the present invention can impart stretchability to a fabric even in a high-density woven or knitted fabric due to the elastic elasticity characteristic unique to polytrimethylene terephthalate in which the main chain of a methylene group expands and contracts.

  In addition, the composite yarn in the present invention can increase the strength of the raw yarn, which is essential for maintaining the raw yarn operability and process passability, by arranging polylactic acid as a sea component. The raw yarn strength is preferably 3.0 cN / dtex or more. If the raw yarn strength is less than 3.0 cN / dtex, the raw yarn strength is too low and the operability of the raw yarn deteriorates. In addition, even in higher-order processes, single yarn breakage, fluff, etc. cause process passability and product quality deterioration. Will occur. In order to further improve the raw yarn operability and process passability, the raw yarn strength is preferably 3.3 cN / dtex or more.

  The sea / island component ratio of the sea-island composite yarn in the present invention is 10/90 to 50/50 (weight ratio) from the viewpoint of stability of the composite form, yarn-making property, and productivity. When the composite ratio of the sea component is less than 10%, a composite abnormality occurs, resulting in poor splitting, or even if the composite form is normal, poor splitting due to poor dissolution of the sea component results in sufficient softness. Can't get. On the other hand, when the composite ratio of the sea components exceeds 50%, the productivity is lowered, and when the woven or knitted fabric is formed, “futsukuki” is generated and the knitted or knitted fabric has no rebound. The sea / island component ratio of the sea-island composite fiber is more preferably 15/85 to 40/60.

  In the composite yarn of the present invention, the fiber surface may be completely covered with the sea component, or the island component may be partially exposed. Further, the cross-sectional shape of the island component after removing the sea component may be a cross-sectional shape such as a flat shape or a triangular shape in addition to the round cross-section.

  Furthermore, the composite yarn in the present invention can avoid the deterioration of the yarn-making property due to composite abnormality or the like by setting the number of island components in the cross section of the single fiber to 3 to 100, and also make the single yarn fineness of the island component appropriate. Therefore, it becomes easy to achieve both the spinning property and the soft feeling. A more preferable island component number is 6-80. The number of island components and the fineness of the composite yarn may be appropriately set so that the fineness (0.01 ≦ FDT (dtex) ≦ 1) of the ultrafine yarn after the alkali weight reduction becomes a desired value.

  The composite yarn in the present invention can be produced using a known apparatus for composite yarn spinning. For example, FIG. 3 of JP-A-57-47938 and FIG. 2 of JP-A-57-82526. Can be manufactured using the device shown in FIG.

  In producing the composite yarn in the present invention, any method such as a method in which spinning and drawing processes are continuously performed, a method in which the yarn is once wound as an undrawn yarn and then drawn, a method in which relaxation heat treatment is performed after drawing, or a high-speed yarn making method is used. It can also be applied to processes.

  Furthermore, yarn processing such as false twisting and air entanglement may be performed as necessary.

  In weaving a high-density fabric with the composite yarn in the present invention, a rapier loom, a water loom, an air jet loom, or the like can be used.

When dyeing, it is preferable to use the softer relaxation or liquid flow relaxation method as a relaxation scouring process in order to increase the density. When reducing the alkali, use an aqueous sodium hydroxide solution to reduce the amount. Can do. It is preferable to reduce the amount by using a sodium hydroxide aqueous solution heated to 80 ° C. or higher because the alkali weight loss time can be shortened. Further, it is more preferable that the high-density fabric of the present invention is made into ultrafine yarn by weaving the composite yarn and then performing alkali weight loss.

  Hereinafter, the present invention will be described in more detail with reference to examples. In addition, each characteristic value in an Example was calculated | required with the following method.

A. Boiling water shrinkage (SWA)
Wrap 10 times on a measuring instrument with a circumference of 0.8 m under a tension of 90 mg / dtex, remove the waste, leave it for 10 minutes, and measure the length (L). Then, this case was wrapped with gauze, hydrothermally treated under no load at 98 ° C. for 20 minutes, suspended on a 2 cm or less rod and allowed to stand for about 12 hours, then the case length (L1) was measured and calculated by the following formula: .
・ Boiling water shrinkage (SWA) = (L−L1) / L × 100
B. Dry heat shrinkage (TWA)
The casserole treated with boiling water by the above method is wrapped with gauze, and only when obtaining ultrafine yarn from the sea-island composite yarn, it is treated under no load until it completely dissolves the sea component with a 3% aqueous sodium hydroxide solution at 98 ° C. After leaving it at room temperature for about 12 hours, it is treated in a dryer at 160 ° C. under no load for 5 minutes. Then, after hanging on a rod of 2 cm or less and allowing to stand for about 12 hours, the length of the case (L2) was measured and calculated by the following formula.
-Dry heat shrinkage (TWA) = (L1-L2) / L2 × 100
C. Single fiber fineness (FDT)
After the casserole was treated with boiling water and alkali reduced by the above method, it was cut to a length of 10 cm with a weight of 0.1 g / dtex, and the single fiber fineness was measured by measuring the weight of the single fiber.

D. Strength Measured according to JIS L1013 (1999) using Tensilon UCT-100 manufactured by Orientec Corporation.

E. Intrinsic viscosity [η]
A sample of 0.10 g was dissolved in 10 ml of orthochlorophenol and measured using an Ostwald viscometer at a temperature of 25 ° C.

  In addition, evaluation in an Example was performed with the following method.

(1) Evaluation of yarn-making property The yarn-making property was evaluated in four stages from the number of yarn breakage at a spinning time of 24 hours.
○○: No thread breakage ○: Thread breakage (1 to 2 times)
Δ: Thread breakage (3-5 times)
×: Many yarn breaks (more than 5 times)
(2) Evaluation of elaborate feeling The sensory evaluation of the fine feeling of the woven fabrics obtained by the methods described in Examples and Comparative Examples was performed based on tactile sensation (fineness of texture) and appearance (cleanness of the surface). Under the present circumstances, the textile of the comparative example 3 which is a conventional product was made into a standard, 4-step evaluation was performed on the following references | standards, and the evaluation result of 10 panelists was averaged and determined.
○○: Extremely sophisticated
○: Somewhat elaborate,
Δ: Texture equivalent to standard fabric,
X: There is no fine feeling (the texture is rough and the surface is not messy).

(3) Evaluation of soft feeling The softness of the woven fabrics obtained by the methods described in Examples and Comparative Examples was sensoryly evaluated by tactile sensation. Under the present circumstances, the textile of the comparative example 3 which is a conventional product was made into a standard, 4-step evaluation was performed on the following references | standards, and the evaluation result of 10 panelists was averaged and determined.
○○: Extremely soft texture,
○: Slightly soft texture,
Δ: Texture equivalent to standard fabric,
X: Hard texture.

(4) Evaluation of color developability The color developability of the fabrics obtained by the methods described in Examples and Comparative Examples was sensory-evaluated by appearance. Under the present circumstances, the textile of the comparative example 3 which is a conventional product was made into a standard, 4-step evaluation was performed on the following references | standards, and the evaluation result of 10 panelists was averaged and determined.
○○: Extremely good color development,
○: Slightly good color development,
Δ: Color development equivalent to standard fabric,
X: Color developability is poor.

Example 1
After transesterification was carried out while distilling methanol at 140 ° C to 230 ° C using tetrabutyl titanate as a catalyst in 19.4 kg of dimethylterephthalic acid and 15.2 kg of 1,3-propanediol, the temperature was kept constant at 250 ° C. Polymerization was conducted for 3.5 hours under the above conditions to obtain polytrimethylene terephthalate having an intrinsic viscosity [η] of 0.96.

  Using polytrimethylene terephthalate obtained by the above production method as an island component, using poly-L-lactic acid with an optical purity of 98.0% as a sea component, at a composite ratio of sea / island = 20/80 (weight ratio), A sea-island type compound base having 70 islands and 12 holes was wound with a compound spinning machine at a spinning temperature of 250 ° C. and a take-up speed of 1500 m / min. Subsequently, the undrawn yarn is drawn using a normal hot roll-hot roll drawing machine at a drawing temperature of 80 ° C. and a heat setting temperature of 120 ° C. so that the drawn yarn has an elongation of 35%. And a 56 dtex-12 fil drawn yarn was obtained. Table 1 shows the yarn physical properties of the obtained drawn yarn.

  The obtained drawn yarn is used for warp and weft to weave a plain fabric having a warp density of 145 (line / inch) and a horizontal density of 95 (line / inch), scouring with hot water at 95 ° C., and then 160 ° C. Then, a dry heat set was performed, and the weight was reduced with a 98% 3% aqueous sodium hydroxide solution until the sea components were completely dissolved. Table 1 shows the results of evaluation of the obtained fabric characteristics. In Example 1, the spinning property was good, and the obtained woven fabric was excellent in fineness, softness, and good color developability.

Example 2
In Example 2, weaving and processing were performed in the same manner as in Example 1 except that a relaxed heat treatment was performed at a heater temperature of 130 ° C. and an overfeed rate of 10% using a drawn yarn in the same manner as in Example 1. Obtained. Table 1 shows the results of evaluating the properties of the drawn yarn and the woven fabric. The fabric obtained in Example 2 was excellent in fineness, softness, and good color development.

Comparative Example 1
In Comparative Example 1, the same polytrimethylene terephthalate as in Example 1 was used, and a winding having a hole number of 250 was used to wind up with a normal spinning machine at a spinning temperature of 250 ° C. and a take-up speed of 1500 m / min. A woven fabric was obtained by weaving and processing the obtained drawn yarn in the same manner as in Example 1 except that the alkali weight loss rate was set to 20%. Table 1 shows the results of evaluating the properties of the drawn yarn and the woven fabric. In Comparative Example 1, the yarn-making property was poor and the yarn breakage occurred frequently. Further, the obtained woven fabric had a rough surface and lacked a sense of precision.

Comparative Example 2
In Comparative Example 2, polytrimethylene terephthalate similar to Example 1 was used as the island component, and polyethylene terephthalate having an intrinsic viscosity [η] of 0.56 copolymerized with 4.5 mol% of 5-sodium sulfoisophthalic acid was used as the sea component. Using the same die and compound spinning machine as in Example 1, the yarn was wound at a spinning temperature of 280 ° C. and a take-up speed of 1500 m / min, and the obtained undrawn yarn was obtained in the same manner as in Example 1. The obtained drawn yarn was woven and processed in the same manner as in Example 1 to obtain a woven fabric. Table 1 shows the results of evaluating the properties of the drawn yarn and the woven fabric. In Comparative Example 2, the yarn-making property was poor and yarn breakage occurred frequently. Further, the obtained woven fabric had a rough texture and lacked a sense of precision.

Comparative Example 3
In Comparative Example 3, polyethylene terephthalate having an intrinsic viscosity [η] of 0.55 was used as the island component, and copolymer polyethylene terephthalate similar to that in Comparative Example 2 was used as the sea component. Got. The obtained drawn yarn was woven and processed in the same manner as in Example 1 to obtain a woven fabric. Table 1 shows the results of evaluating the properties of the drawn yarn and the woven fabric. In Comparative Example 3, the color developability was poor and the texture was bulky.

Examples 3-4, Comparative Example 4
The fineness composition, the sea / island composite ratio, and the number of islands were changed as shown in Table 2, and drawn yarn and woven fabric were obtained in the same manner as in Example 1. Table 2 shows the properties of the obtained drawn yarn and the evaluation of the fabric.

  In Examples 2 and 3, the yarn-making property was good, and the resulting woven fabric was good in fineness, softness and color development.

  On the other hand, in Comparative Example 4, since the sea component composite ratio is as high as 60%, the yarn-making property is slightly inferior, and only a touched fabric is obtained by forming a large gap between the fibers by removing the sea component. It was.

Comparative Example 5
A drawn yarn and a woven fabric were obtained in the same manner as in Example 1 except that the heat setting temperature in the drawing process was 90 ° C. Table 2 shows the properties of the obtained drawn yarn and the evaluation of the fabric. In Comparative Example 5, the shrinkage was too strong and the texture was hard.

Claims (5)

An ultrafine yarn comprising a yarn substantially composed of polytrimethylene terephthalate, and having a dry heat shrinkage rate (TWA) and a single fiber fineness (FDT) satisfying all of the following formulas.
(1) 5 ≦ TWA (%) ≦ 20
(2) 0.01 ≦ FDT (dtex) ≦ 1 The island component is composed of polytrimethylene terephthalate and sea component polylactic acid, and is obtained by alkali reduction of a sea island type composite yarn having a sea component / island component ratio of 10/90 to 50/50. The ultrathin yarn according to claim 1. The ultrafine yarn according to claim 1 or 2, wherein the boiling water shrinkage (SWA) and the dry heat shrinkage (TWA) after alkali reduction satisfy TWA (%) / SWA (%) ≥1. The ultrathin yarn according to claim 2 or 3, wherein the sea-island composite yarn has an original yarn strength of 3.0 cN / dtex or more. A high-density fabric using the ultrafine yarn according to any one of claims 1 to 4 for warp and / or weft.