JPH0138893B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing a false-twisted, untwisted, alternately twisted yarn to which a specific adhesive is attached and which is excellent for use in shrinkage fabrics. Conventionally, many attempts have been made to produce highly twisted yarn-like fabrics using fused untwisted yarns or untwisted alternating yarns by fusion bonding. First, thermoplastic synthetic fibers made of a single component,
This is a method of false twisting while fusion bonding.
This is shown in Japanese Patent Publication No. 49457, Japanese Patent Publication No. 55-51048, etc. In these, the components that make up the thread, such as polyester itself, are heated to 230°C.
Alternatively, it is subjected to false twisting at a high temperature of 240℃.
Fabrics with excellent silkiness can be obtained. However, since the false twisting is fixed at a very high temperature, the twisting strain is almost completely lost, and the potential torque in the untwisting direction has disappeared. For this reason, the ability to develop grains is extremely poor. There is also a proposal for false twisting using a composite yarn consisting of the main component of the yarn and an adhesive component.
For example, as in Japanese Patent Publication No. 49-40031, melting point
This method uses a composite yarn of copolymerized polyester at 223°C and polyethylene terephthalate (hereinafter abbreviated as PET) with a melting point of 257°C, and false twists the former components while melting them. In this case, too, there is a lack of wrinkle ability due to the high temperature of 210℃ or higher required to fix the false twist, and it is quite difficult to remove the adhesive component at the center of the yarn, resulting in poor drapability, stiffness and wrinkles. It becomes a textile. Furthermore, a method has also been proposed in which the adhesive component is attached to the yarn without spinning, and the yarn is subjected to a post-false twisting process.
This is a method similar to Japanese Patent Publication No. 37-8613, in which the false twist is fixed with a thermosetting urea resin. In this case, although it is possible to obtain an untwisted part with the resin, since the resin is thermosetting, the bonded part is brittle and the bending of the yarn during graining is completely inhibited, so that the grain does not appear. . Also, special public service in 1977-
In the case of fixing the twist with carboxymethyl cellulose as seen in the example of Publication No. 12891, the adhesive becomes very brittle and becomes a white powder after drying, and is not strong enough to fix a strongly twisted structure with a high twist density. It is enough. Therefore, the present inventors conducted intensive studies on fusion-bonded alternately twisted yarns that can produce a flexible wrinkled fabric without losing the latent torque in the untwisting direction necessary for graining, and as a result, they arrived at the present invention. . That is, the present invention provides: ``(2) When false-twisting a multifilament made of thermoplastic synthetic fibers, the following adhesive is applied to the filament in advance, and then 180%
A method for producing yarn for shrinkable textiles, characterized by subjecting the yarn to adhesive twisting and fixed false twisting at a temperature of 0.degree. C. or lower. (However, the above adhesive has a melting point of 180℃ or less,
And the saturated solubility in hot water at 98℃ is 7.0g/
ml or more of a polyester copolymer dissolved in water. )”. The present invention will be described in more detail. In the present invention, thermoplastic synthetic fibers include polyester, polyamide, and the like. The first feature of the present invention is that a water-soluble hot-melt polymer having a lower melting point than thermoplastic synthetic fibers is used, and an aqueous solution of the polymer is attached to the yarn before the false twisting process. . In the known method of composite spinning thermoplastic synthetic fibers and adhesive components, due to the relationship of melt viscosity during melt spinning, it requires advanced technology to simultaneously spin adhesive components that have a large difference in melting point from the thermoplastic synthetic fibers. . For this reason, it is usually necessary to use an adhesive component with a high melting point, and during the fusion false twisting process, it is necessary to fix the twist at a high temperature.
The potential torque in the untwisting direction is extremely reduced. On the other hand, in the method of the present invention, there is no need to consider simultaneous spinnability, and an adhesive component with a very low melting point compared to thermoplastic synthetic fibers can be attached to the yarn, eliminating potential torque. This makes it possible to perform adhesive twisting and fixation at extremely low temperatures. Furthermore, in the method of the present invention, since the hot-melt adhesive is water-soluble, there is no need to bring the adhesive into a hot-melt state.
It is simple in terms of equipment and can be attached to threads very easily. In order for the adhesive to adhere to the yarn being fed, the viscosity of the adhesive must be several thousand centipoise or less, and a lower viscosity is desirable. However, when the viscosity is low, the viscosity cannot be lowered very much, for example, in a process in which the yarn is rotated, such as in a false twisting process. This is because the adhesive scatters to the surroundings considerably, reducing the adhesion efficiency. In this respect, it is more efficient to attach it to the threads that are being fed in a non-twisted state. As mentioned above, it is important that the adhesive is of a heat-melting type. This is because the adhesive attached to the yarn needs to undergo thermoplastic deformation into a strongly twisted state at the same time as the thermoplastic synthetic fibers, which are the main component of the yarn, in the next false twisting process. be.
If a thermosetting adhesive is applied to yarn in advance and false twisting is performed, the adhesive will peel off or the yarn will break, making it impossible to obtain the desired alternately twisted yarn structure. Further, the adhesive used in the present invention must be capable of bonding by low-temperature false twisting. Melting point: 180℃
Temperatures exceeding this temperature are not preferred because good grains cannot be obtained.
Further, the adhesive of the present invention needs to have a saturated solubility in hot water of 98°C of 7.0 g/100 ml or more. This is to obtain substantial adhesive strength.
If the saturated solubility is less than 7.0 g/100 ml, the solution concentration will be too dilute and a good adhesive will not be obtained. The adhesive in the present invention needs to be a polyester copolymer. This is because it has strong adhesive strength with polyester fibers, etc., can be bonded by heat melting, and is easy to remove after forming a fabric.
A preferred adhesive is one copolymerized with a 5-sodium sulfoisophthalic acid component. In addition, it may be copolymerized with a 5-alkali metal sulfoisophthalic acid component such as a 5-lithium sulfoisophthalic acid component and a 5-potassium sulfoisophthalic acid component. Furthermore, when a 5-sodium sulfoisophthalic acid component is copolymerized, it is preferable that the component is copolymerized in an amount of 3 mol % or more, particularly 5 mol % or more. This is because it can be easily removed by hydrolysis with an alkaline aqueous solution. Such polyester copolymer adhesives include, for example, difunctional carboxylic acids such as terephthalic acid, isophthalic acid, naphthalene dicarboxylic acid, adipic acid, sebacic acid, dodecanoic acid, 5-sodium sulfoisophthalic acid, and ester derivatives thereof. and polyoxymethylene glycols such as ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, trimethylene glycol, tetramethylene glycol, polyethylene glycol, polytetramethylene glycol, 1,4-cyclohexanediol, 1,4-cyclohexane Dimethanol, 1,
6-hexanediol, propylene glycol,
Polyester or polyester polymer consisting of a diol compound such as 1,5-pentanediol,
and how to combine these with benzoylbenzoic acid, benzyloxybenzoic acid, methoxypolyethylene glycol, polyoxymethylene glycol, glycerin, pentaerythritol, trimellitic acid, trimesic acid, and their derivatives, such as polyesters or polyester polymers. Good too. The yarn to which the adhesive having the properties described above is attached is fed to the false twisting process and fused and untwisted, but the yarn is processed at a temperature that does not eliminate the potential torque in the untwisting direction. It is very important to. The lower the temperature, the more preferable it is, but due to the thermal properties of polyester, a temperature of 180°C, preferably 150°C or lower, is sufficient to cause the potential torque to cause graining. The step of attaching the adhesive can be arbitrarily selected before the false twisting step. An example of the adhesion process will be explained using figures. In FIG. 1, the yarn spun by a spinneret 1 is cooled and then nipped by nip rolls 10, and then adhesive is applied by an adhesive application device 2. The film is dried by the drying method, passed through the delivery roll 20, and then wound onto the drum 30. The resulting yarn can be semi-drawn, undrawn, or 6000
At a spinning speed of m/min or more, the yarn has a high degree of orientation and crystallinity and is comparable to drawn yarn. In the case of undrawn yarns or semi-drawn yarns, they are subsequently fed to the drawing or drawing and simultaneous false twisting process. In the case of directly spun drawn yarn, it can be supplied as is to the false twisting process.
Figure 2a shows that the spun yarn is Nitzprol 11
This is an example in which the adhesive is attached and dried while being stretched by the delivery roll 21. FIG. The adhesive is applied between the rolls 22 and dried. In these two cases, the yarn obtained is directly fed to the false twisting process. Third
In Figure a, the semi-drawn yarn or undrawn yarn 7 is stretched between the feed roll 14 and the delivery roll 24 while the adhesive is attached and dried. Figure 3b
After being stretched by the feed roll 15 and the first delivery roll 16, an adhesive is applied and dried, and the film is sent out by the second delivery roll 26. The yarns obtained according to these two examples are then fed to false twisting. The example shown in FIG. 4 is a method in which an adhesive is applied on the false twisting machine before being supplied to the false twisting area, and the drawn yarn, undrawn yarn, or undrawn yarn 7 is attached to the roll 17. Between 18
After being coated with adhesive and dried, it is supplied to a false twisting area without being wound up, and after being false twisted by a heater 5 and a false twisting spinner 6, it is passed through a delivery roll 19 to a cheese 31. It is wound up. When applying this adhesive, by applying intermittent adhesion to the feeding yarn, there are areas where the false twist is fixed by the adhesive, and areas where the adhesive is not attached and are opposite to the false twist. with a part in a state of strong twist in the direction,
Alternately twisted structured yarn can be obtained. In this case, it is possible to actively control the length of the bonded portion, and it is suitable for obtaining alternately twisted yarn with a long cycle. As a device for applying the adhesive to the yarn, it is preferable to use a roll coater or a guide-like adhesive gushing device. The bonded alternately twisted strongly twisted yarn obtained by this method has a large potential torque in the untwisting direction, has excellent wrinkle resistance, and is flexible because the adhesive can be easily removed with a hot alkaline aqueous solution. Fabrics without dyeing spots can be obtained. This will be explained below using examples. Example 1 Dimethyl terephthalate and dimethyl isophthalate were copolymerized at a ratio of 6:4, and the mol%
A polyester copolymer polymer consisting of an acid component copolymerized with 5-sodium sulfoisophthalic acid and a glycol component containing 65:35 of ethylene glycol and diethylene glycol was obtained. The melting point was 130°C. Table 1 shows the amount of 5-sodium sulfoisophthalic acid added and the solubility when dissolved in hot water at 98°C for 30 minutes. PET75D-36f was prepared using these aqueous solutions using the process shown in Figure 3b.
I attached it to the thread and wound the thread. At this time, a hollow heater at 180°C was used for drying. The obtained thread,
False twisting was performed at a temperature of 130°C. The processing conditions were: processing speed: 200 m/min feed rate: +12.5% false twisting method: friction false twisting method. The results showed that 5-sodium sulfoisophthalate
The copolymer copolymerized with 5.0 mol % had a saturated dissolution in hot water of 7.1 g/100 ml, and an alternately twisted structure was formed, resulting in a good textured fabric (No. 3). Also 5-sodium sulfoisophthalic acid 7.0
A good alternate twist structure was generated in both the mol% level (No. 4) and the 9.0 mol% level (No. 5), and a good textured fabric was obtained. On the other hand, experiment No. 1
In No. 2, the hot water saturated solubility of each adhesive was low, so good adhesion could not be achieved and the desired alternately twisted yarn could not be obtained.

[Table] Example 2 The polymer containing 7 mol% of 5-sodium sulfoisophthalic acid described in Example 1 was attached.
False twisting was performed using PET75-36f yarn. The false twisting conditions were the same as in Example 1 except for the processing temperature.
The false twisting temperatures at this time are 130℃, 150℃, 178℃
Five levels were selected: ℃, 183℃, and 200℃. The obtained yarn was woven using a 50D-24f, 300T/m lightly twisted yarn as a warp yarn, and subjected to graining treatment. When we measured the width of the fabric that structurally shrinks due to graining, it was 29%, 23%, 20%, and 15%, respectively.
%, 8%, almost no wrinkles appeared at the 200°C level, and wrinkles were observed at the 183°C level. However, the graininess was somewhat insufficient for practical use. The levels of 178℃, 150℃ and 130℃ were well grained. All levels where these grains are well developed are
Immerse in a hot aqueous solution of 50g/sodium hydroxide.
After processing for 30 minutes, they were all very flexible.
A fabric with a real twist and a strong twist texture and less bulkiness was obtained. Furthermore, this fabric was immersed in a cationic dye solution and treated with hot water, but it was not dyed and it was confirmed that the adhesive component had been removed.

[Brief explanation of drawings]

1 to 4 are schematic illustrations of an example of a process for applying the adhesive of the present invention. FIG. 1 shows an example of attachment during high-speed spinning and winding, and FIGS. 2a and 2b show examples of attachment during the direct spinning and drawing process. FIG. 3 shows a stretching process, ie, method (a) in which the film is attached simultaneously with stretching, and method (b) in which the film is attached in a separate zone from the stretching. FIG. 4 shows the method of attachment on a false twisting machine. 2: Adhesive supply device, 3: Drying device, 4: Stretching hot plate, 5: False twisting heater, 6: False twisting spindle.

Claims (1)

[Scope of Claims] 1. When false-twisting a multifilament made of thermoplastic synthetic fibers, the following adhesive is applied to the filament in advance, and then the adhesive twisting and fixed false-twisting process is performed at a temperature of 180°C or less. A method for producing yarn for shrinkable textiles, characterized by: (However, the above adhesive refers to a polyester copolymer with a melting point of 180°C or less and a saturated solubility in hot water of 98°C of 7.0 g/ml or more, and the copolymer is dissolved in water. .) 2. The method for producing a yarn for shrinkable fabrics according to claim 1, characterized in that the adhesive is applied intermittently in the longitudinal direction of the filament.