JPS6262183B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for manufacturing polyester fiber structures. Conventionally, polyester fiber structures manufactured by ordinary drawing methods and having a uniform structure along the longitudinal direction of the yarn have been widely reduced in weight using strong alkalis such as caustic soda in order to improve the texture. ing. However, yarn A using raw silk, which is a polyester fiber that has substantially random unstretched parts and stretched parts in the same yarn, has a special texture due to its thick and thin non-uniform structure, and dark and light marbling when dyed. Although it is a material with features such as the appearance of patterns, it deteriorates extremely strongly during weight reduction processing.
A fatal problem was that it could not be applied to the field of thin fabrics where weight reduction processing is essential. Regarding weight loss processing methods, there are generally dipping methods such as hanging kneading, pad steaming methods, and cold batch methods, and each method has a different weight loss effect, but the fabric made of yarn A can be processed by any of the methods. When the weight loss rate is about 10%, the yarn strength becomes less than 1 g/d, which is not suitable for practical use. The reason why the fabric made of yarn A deteriorates extremely strongly due to weight loss processing is due to the difference in weight loss rate based on the difference in physical properties between the unstretched part and the stretched part.
It is presumed that this is due to intensive hydrolysis of the unstretched area, and the above results indicate that changing the alkali treatment method or conditions to avoid this phenomenon will have little effect. shows. Since the cause of deterioration is the easy weight loss of the unstretched part,
As a means to improve this, it is possible to increase the orientation and crystallinity of the undrawn part, but such treatment at the spinning stage involves a significant change in the fiber properties, which is a characteristic of yarn A. This is not preferable because it results in the loss of the pattern of appearance of the shaded color difference and the loss of the special texture. In order to solve these problems, the inventors of the present invention have conducted intensive research and have found that the above-mentioned drawbacks can be improved by using a mixture of polyester fibers having a specific alkali weight loss rate, and have thus arrived at the present invention. That is, the present invention provides a polyester yarn A having randomly unstretched portions and stretched portions in the same yarn.
and an alkaline hydrolysis rate that is 1.0 to 5.0 times higher than the alkaline hydrolysis rate of an undrawn polyester yarn that has a substantially uniform structure along the longitudinal direction of the yarn and has a birefringence that is approximately equal to that of the undrawn portion of the yarn A. The present invention relates to a method for producing a polyester fiber structure, which is characterized by subjecting a fabric-like article containing a polyester yarn B having a high velocity to a weight reduction treatment. The polyester fiber yarn A as used in the method of the present invention is a filament yarn obtained from polyethylene terephthalate or a copolyester having ethylene terephthalate as a main constituent unit,
This is a yarn in which unstretched areas that are potentially easily dyed and stretched areas that are difficult to dye exist alternately and randomly in the same yarn. Usually, the unstretched part is thick in the fiber axis direction, and the stretched part is thin.The ratio of the diameters of the thickest part and the thinnest part of a single fiber is not particularly limited, but is approximately 1.2 to 1.65. Yes, preferably 1.2~
1.5, and although it is not particularly limited, the birefringence of the thick part is usually 15×10 ^-3 to 80×
10 ^-3 , preferably 25 x 10 ^-3 to 80 x 10 ^-3 , and a thin part having a birefringence of 90 x 10 ^-3 to 200 x 10 ^-3 is generally used. The length of the thick portion is preferably 100 mm or less, and the overall abundance ratio of the thick portion is preferably in the range of 1:1 to 1:1.5, and most preferably 1:1.3. The first requirement for the yarn B applied to the present invention is that it has a uniform structure with almost no difference in alkali hydrolyzability along the longitudinal direction of the yarn, and in addition, the unstretched yarn A It is necessary that the alkaline hydrolysis rate is 1.0 to 5.0 times faster than the hydrolysis rate of an undrawn polyester yarn having a birefringence approximately equal to 100%. However, an undrawn polyester yarn having a birefringence almost equal to that of the undrawn part of yarn A means that the birefringence of which the alkali hydrolysis rate hardly changes is A±10 ^-3 (where A is the undrawn part of yarn A). It is preferable to use yarns made of polymers having the same composition within the range of 100% birefringence). In addition, the alkaline hydrolysis rate in the present invention refers to undrawn polyester yarn having the same fineness structure as the average fineness of yarn A and having a birefringence A±10×10 ^-3 at 30 g of solid caustic soda at 98°C. The relative comparison is made assuming that the weight loss rate when treated for 60 minutes is 1.0. Since there is usually a positive correlation between the alkaline hydrolysis rate and the degree of modification of polyester, it is recommended to use polyester with a higher degree of modification than yarn A as yarn B that can satisfy these requirements. It will be done.
Specifically, a part of the dicarboxylic acid component of a polyester containing terephthalic acid or its ester derivative as the dicarboxylic acid component and a glycol selected from ethylene glycol and 1,4-butanediol or its ester-forming derivative as the glycol component. , for example, monoalkali metal salts of 5-sulfoisophthalic acid, dicarboxylic acids such as isophthalic acid, diphenyldicarboxylic acid, naphthalene dicarboxylic acid, adipic acid, sebacic acid, dodecanedioic acid, or their esters, p-oxybenzoic acid, p-
It may be substituted with oxycarboxylic acid such as β-oxyethoxybenzoic acid or its ester,
In addition, some of the aliphatic or alicyclic glycols may be replaced with alkylene glycols having 2 to 10 carbon atoms, 1,
It may be replaced with a glycol other than the main glycol component, such as 4-cyclohexanedimethanol, 1,4-bis(β-oxyethoxy)benzene, bisglycol ether of bisphenol A, or polyalkylene glycol. Furthermore, it is also possible to use a small proportion of a chain branching agent such as pentaerythritol, trimethylolpropane, tomelitic acid, trimesic acid, etc., or a polymerization terminator such as monohydric polyalkylene oxide, phenylacetic acid, etc. In addition to modified polymers, examples of materials with a high alkaline hydrolysis rate include ultrafine threads and high-temperature heat-treated threads. It is thought that hydrolysis of polyester by alkali normally proceeds sequentially from the fiber surface layer, and if the same material is used, the smaller the single fiber fineness and the larger the surface area, the faster the hydrolysis rate. The relationship between single fiber fineness and surface area can be roughly expressed by the formula (), and since there is a direct proportional relationship between surface area and hydrolysis rate, for example, if the birefringence is 15 × 10 ^-3 to 80 × 10 ^-3
With the same filament fiber index d ₁ as a specific undrawn polyester yarn in the range of 1.0 to 5.0, the alkaline decomposition rate is
Even for yarn B that is outside the range of , it is possible to roughly estimate the appropriate single yarn fineness d ₂ from the relationship in equation ( ). A ₁ : Surface area of d ₁ fineness A ₂ : Surface area of d ₂ fineness Furthermore, regarding the thermal history, the same material can be heated to 180℃,
Compared to the hydrolysis rate of the one treated with dry heat for 60 seconds, the hydrolysis rate of the one treated with dry heat at 220℃ for 60 seconds is about twice, so it can be applied to Yarn B as appropriate in combination with the difference in single yarn fineness. can. To explain in more detail the structural requirements of the yarn B, the reason why the yarn must have a uniform structure along the longitudinal direction is as follows.
If a strong/weak part exists, the weak part (undrawn part) of yarn A
This is to avoid the fact that if the weak parts of yarn A and yarn B overlap, the strength will be extremely lower than the average strength of each of yarn A and yarn B, and this is to avoid this. The need for an alkaline hydrolysis rate in the range of 1.0 to 5.0 times that of an undrawn polyester yarn with equal birefringence can be illustrated by the following experimental example. Experimental example: Made of ordinary polyethylene terephthalate, with random unstretched parts and stretched parts in the longitudinal direction.
For yarn A of 75D-24F, the polymer used for yarn A is polyethylene glycol (molecular weight 1000).
75D modified by adding 3 to 6% by weight of
After air-mixing 8 types of 24F yarns B ₁ to _{B 8} at a ratio of 1:1, a level of two yarns A pulled together was added, and a double twister was used to create S, Z, and
After twisting at 2000t/m to make a hard-twisted yarn, weaving it into a jersey using the usual method, raising the grain, and intermediate setting, the yarn was weight-reduced to 30g of caustic soda at a temperature of 98°C so that the weight loss rate was approximately 15%. Table 1 shows the results of measuring each yarn strength. In addition, there are also undrawn polyester yarns (hereinafter referred to as yarn C) with a birefringence of 40±10×10 ^-3 that is approximately equal to the birefringence of the undrawn portion of yarn A.
Each individual yarn of B ₁ to _{B 8} is knitted into a tube, and the fabric is opened and
After the intermediate setting, the yarns were subjected to weight loss treatment for 60 minutes under the same conditions as above, and the weight loss rate ratios of yarns B ₁ to B ₈ to yarn C were determined, and the results are also shown in Table 1.

【table】

[Table] As can be seen from Table 1, when the weight loss speed ratio to yarn C is up to 1.91 (yarn B ₁ to yarn B ₅ ), the yarn strength increases as the speed ratio _increases ; yarn
_B8 ), on the other hand, tends to be lower than this. Therefore, the optimum speed ratio is considered to be between 1.91 and 2.72, but based on experience, if the minimum strength that can withstand practical use as a polyester product is 2.5 g/d or more, Therefore, a speed ratio of 1.0 to 5.0 is an acceptable range. Yarn A
Because it is difficult to separate and sample the unstretched and stretched parts, it is not possible to clearly measure the weight loss rate for each, but from the results in Table 1, it is clear that yarns with a weight loss rate ratio of 5 times or more compared to yarn C It is presumed that in the yarn B, the yarn B itself loses weight more than the undrawn portion of the yarn A, making it difficult to maintain strength. In the above experimental example, the fineness of yarn A is
50D - 50D which is the fineness of yarn A' and yarn B of 24F
Eight -24F yarns B' were air mixed at various mixing ratios, and then treated as in the above experimental example. The results are shown in Table 2 below.

【table】

[Table] As can be seen from Table 2, the mixture of yarn A and yarn B of the present invention can be applied within the mixing ratio range of 25/75 to 75/25, as in the case of ordinary blended yarns and mixed yarns. can. The fabric used in the above experimental example was tested by the pad steam method and the cold batch method in addition to the weight loss processing by hanging kneading (experimental example), and the results were similar to those of the hanging kneading method. Therefore, the method of the present invention specifically limits the weight loss processing method. There's no need. In addition, "containing yarn A and yarn B" means that the fabric is formed from yarn A and yarn B or other yarns (fibers) as necessary.
For example, yarn A and yarn B, and other yarns as necessary, may be mixed together to form a fabric by methods such as pulling, blending, twisting, or interlacing, but the examples are limited thereto. It's not a thing. The mixing effect of yarn A and yarn B, such as blending and intertwisting, according to the method of the present invention, is that the mixing of yarn B alleviates the easy weight loss property of the easy weight loss part of yarn A, and improves the resistance to weight loss processability. Instead, a yarn different from yarn A is mixed in, making it possible to create a wider range of expressions in terms of shading and texture. The present invention will be explained in more detail with reference to Examples below, but the present invention is not limited thereto. Example Yarn A of 75D-18F is a polyester yarn whose main constituent unit is polyethylene terephthalate, and has unstretched parts and stretched parts irregularly in the longitudinal direction.
A yarn (a yarn made by aligning two 75D-36F yarns B made by adding 3.8% by weight of ethylene 5-sodium sulfoisophthalate to a polyester whose main constituent unit is polyethylene terephthalate) is spun and drawn. Inventive method) and two yarns A (comparative method) were each twisted at 2400T/2 by an Italian twisting machine.
After twisting M yarn (S/Z twist), 80℃, 45
It was set with steam treatment for 1 minute to prevent it from twisting. This yarn was woven in a conventional manner to obtain 5 pieces each of pear-skinned jersey gray fabrics. Furthermore, each of these 5 squares of greige was embossed under normal conditions, an intermediate setting was performed, and each 1 square was prepared into andon rolls to reduce the weight. Weight loss treatment was performed to achieve a weight loss rate of approximately 5%, 10%, 15%, 20%, and 25%. After successively washing with hot water, unraveling, tying, and drying, yarn A2
The fabrics in this collection (comparison products) are: Dianix Navy Blue ER-FS (disperse dye manufactured by Mitsubishi Kasei) 0.1% owf Dianix Yellow AC-E (dispersed dye manufactured by Mitsubishi Kasei) 0.5% owf IP carrier N-20 ( Dyeing was carried out at 115°C for 60 minutes using a jet dyeing machine (circular type) with a bath composition of 3.0% owf (swelling agent for polyester manufactured by Ichiba Co., Ltd.). In addition, the fabric (product of the present invention) in which yarn A and yarn B are aligned is prepared by adding Estrol Red N-GSL (cationic dye manufactured by Sumitomo Chemical Co., Ltd.) and Ospin KB-30F (dispersion dye manufactured by Tokai Oil Co., Ltd.) to the bath composition described above. Similar to fabrics with 2 yarns A drawn in a bath composition with 1% OWF added, dyeing was carried out using a circular dyeing machine at 115℃ and 60℃.
Staining was performed for minutes. Furthermore, both the comparison product and the product of the present invention were finished under the same conditions to produce products, and the yarn strength of each decomposed yarn was measured using a Tensilon type tensile tester. Table 3 shows the results. Both the 5-level comparative product and the 5-level inventive product produced fabrics with a unique color effect, but while the comparative product only had a shading effect, the inventive product had 3 unique colors, with a more vivid unique color. showed that. Furthermore, as can be seen from the results in Table 3, the thread tenacity of the comparative product is less than 2.5 g/d even with a weight loss rate of about 5%, whereas the yarn strength of the product of the present invention surprisingly has a weight loss rate of 25 g/d.
Even with a % weight loss of 2.5 g/d, the product has become a product that can withstand practical use. The alkali decomposition rate of the yarn B used was measured and the result was 1.5.

【table】

【table】

Claims (1)

[Claims] 1 A polyester yarn A having unstretched parts and stretched parts randomly in the same yarn, and a nearly uniform structure along the longitudinal direction of the yarn, and a birefringence that is almost equal to the unstretched part of the yarn A. A polyester fiber structure characterized in that a fabric-like material comprising a polyester yarn B having an alkali hydrolysis rate 1.0 to 5.0 times higher than the alkali hydrolysis rate of an undrawn polyester yarn having the above is subjected to a weight reduction treatment with an alkali. How things are manufactured.