JPS6140774B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing a false-twisted yarn that exhibits a harmonious neutral color by mixing two types of yarns with different dyeability. It is widely and generally practiced to mix two yarns with different dyeability to form a so-called heathered yarn. For example, two yarns with different dyeability are twisted together, two yarns are false twisted, or two undrawn yarns with different dyeability are stretched simultaneously or subsequently. A method of false twisting is known. It is important for yarns with a heathered effect to appropriately disperse the tone pitch pattern in knitted fabrics obtained using the yarns, but if the manufacturing conditions of the yarns are inappropriate, The biggest problems are uneven color tone, distorted patterns, and defective products. For example, if the length of the different color tones is too long, it will cause discomfort, and if the pitch between the different color tones is too uniform, it will cause a so-called heather flow defect. Furthermore, if the degree of color tone dispersion differs in the length direction, each piece of fabric will have a different pattern. All of these defects are caused by the dispersion of two yarns with different dyeability and unevenness in mixed fibers. The present invention provides a method of completely dispersing and mixing two yarns with different dyeability to produce a yarn that exhibits a harmonious neutral color without the above-mentioned unevenness. In other words, the present invention provides (A) and (B)2 with different stainability.
When the different thermoplastic multifilament undrawn yarns are combined and subjected to stretching and false twisting at the same time, the two yarns are passed through a feed roller in a separated and independent state, and the two types of yarns are passed between the feed roller and the heat fixing device. A doubling control device is installed at a position where the multifilaments are in an undrawn state, and the two types of multifilament undrawn yarns are doubled so that the entry angles of the two types of undrawn yarns toward the false twisting start point are substantially the same. This is a method of friction false twisting while heat setting at a temperature that does not cause the multifilaments to fuse together. The first feature of the present invention is a method of piling two yarns with different dyeability, and the piling is performed for the first time using a piling regulating device provided between a feed roller and a heat fixing device. A method similar to the method of doubling yarns using the doubling regulating device of the present invention has already been proposed. For example, Tokukai Akira
Publication No. 52-110959 discloses that two yarns having different softening points and dyeability are separated by regulating the positional relationship of the two yarns at the time of plying and twisting, and fusing and false twisting the two yarns. This method fixes the positional relationship, produces heathered yarn with uniform tone pitch, and excellent contrast. In addition, in Japanese Patent Application Laid-open No. 49-50259, Figure 1a
As shown in , in order to wrap the other yarn supplied from the other feed roller around one yarn during false twisting, a pin 2 (expressed as a guiding member) etc. is used to define the twisting start point. It is proposed that a In this case, since yarn (B) is wound around yarn (A), the yarn entry angle is θ<θ'. Furthermore, in Japanese Patent Application Laid-open No. 52-1126, out of two types of yarns to be doubled fed from the same feed roller, one yarn is heat treated, and the other yarn is unheated and then doubled. It has been proposed to provide a bar to prevent twisting when false twisting is performed. The method disclosed in JP-A-52-110959 uses the difference in softening point between two yarns to heat set the yarn to such an extent that one yarn is not fused but the other yarn is fused. False twisting is performed at high temperature, and fixing by fusion is an essential requirement in order to fix the mutual positional relationship of the two yarns. Also, JP-A-49-50259
No. 52-1126 or Japanese Unexamined Patent Publication No. 1126/1987 both aim to create a substantial difference in yarn length between the two types of yarn by winding one yarn around the other yarn. This is what I did. Unlike these methods, the present invention makes the twist configurations of the two yarns substantially the same at the twisting start point, and then heats the two yarns substantially equally in the heat setting area of the false twisting step. When the filaments are fixed and then untwisted using a friction false twisting device, the filaments of the two yarns are completely mixed by untwisting them in the same manner. It is something. Therefore, the obtained mixed yarn is a false twisted yarn exhibiting a color tone intermediate between the two original yarns. Naturally, no fusion occurs, and if fusion occurs, it would be impossible to obtain a neutral color, so the heat setting temperature during stretching and false twisting should be such that neither of the two yarns are fused. There is a need. In addition, in the method of winding one of the yarns to create a substantial difference in yarn length between the two types of yarn, in the resulting mixed yarn, component yarns with longer yarn lengths partially As a result, the colored yarns of the component yarns appear as stripes, impairing the uniform neutral color effect. The second feature of the present invention is that a friction false twisting device is used as the false twisting device. For example, a three-axis false-twisting device (external type) having a rotating friction disk, or a false-twisting device (internal type) in which the yarn is false-twisted in contact with the inside of a rotating cylinder can be used.
This is presumed to be because when the false-twisted yarn is untwisted in the false-twisting device, the circumferential direction is rubbed, so that each filament of the two yarns is mixed more completely. If a false twisting device is used, for example, the well-known false twisting pin spindle system, this fiber mixing will be insufficient and the purpose cannot be achieved. The present invention will be explained in further detail. The yarn doubling method according to the present invention uses a yarn doubling regulating device 2 as shown in FIG. The difference in θ′ is
Twisting is started within 10 degrees, preferably within 5 degrees. By employing such a method, the two yarns occupy the same positional relationship in the twisted state and undergo the same thermal history in the subsequent heat treatment, thereby eliminating unevenness in the length direction of the yarn. It shows no stainability. On the other hand, if such a doubling control device is not used, for example, if the two undrawn yarns are pulled together in front of a feed roller, the positional relationship in the twisted state of the two undrawn yarns will be completely random, resulting in uneven heat treatment and the length of the yarns. It is assumed that uneven dyeing occurs in the width direction, and when it is made into a knitted fabric, the dark or light dyed areas with different dyeing properties appear in short stripes, making it impossible to obtain the desired neutral color effect. be done. Furthermore, if such unevenness exists in the twisted yarn state, the condition in which dark and light component yarns should exist in a certain positional relationship in any part is disrupted, so even if sufficient fiber mixing is performed, the Since some parts are dyed darker or lighter than other parts, the effect of presenting a uniform neutral color will be impaired. Furthermore, in addition to the unevenness of heat treatment, such a method seems to have a poor fiber mixing effect. An example of a specific embodiment is shown in FIG. In Figure 2, two types with mutually different staining properties (A),
The undrawn yarn is pulled out from the undrawn yarn packages 11 and 11' in (B) and passed through the feed roller 1,
The yarn is doubled by the yarn doubling regulating device 2, and stretched and false-twisted between the feed roller 1 and the second roller 6 via the heat fixing device 3, the cooling plate 4, and the false twisting device 5, and then the second roller 6 After the heat treatment is performed in the heat treatment device 7 between the roller and the third roller 8 and the secondary setting is performed, the winding device 9
It is something that is wound up. 10 is various thread guides. The yarn doubling regulating device 2 in FIG. 1 is illustrated using a separate pin, but a guide or the like may also be used. For example, a separate pin, guide, or rod whose surface is chromed and sandblasted and has a surface roughness of about 0.5 to 10 seconds, or a separate pin, guide, or rod made of ceramic material and whose surface roughness is about 0.5 to 10 seconds. A material with a low coefficient of friction is preferable.
These doubling regulating devices may be inserted between the two types of undrawn yarns, or may be used to fix the yarn path of each multifilament, but in either case, the device is connected to the heat fixing device 3 and the feed roller 1. It is necessary to install it between Although FIG. 2 shows a form in which a secondary set is performed, the secondary set may be omitted and the invention is not limited to this form. The false twisting device 5 must use a friction false twisting method. The two types of thermoplastic multifilament undrawn yarns (A) and (B) with different dyeability are yarns in which the same color (including shading effect) cannot be obtained when the yarns are dyed with the same dye; For example, there are polyethylene terephthalate fibers dyeable with basic dyes and polyethylene terephthalate dyeable with disperse dyes, or polyethylene terephthalate fibers and polyamide fibers, as well as thermoplastic fibers dyed with different hues and shadings, and ordinary fibers and dyed solution dyed. It also includes combinations of fibers. Generally known conditions can be used for the stretching and simultaneous false-twisting conditions, but it is not preferable to use too high a heat setting temperature because it tends to cause fusion and fuzz. Further, with respect to the friction false twisting device, fuzz is likely to occur if, for example, a three-axis circumscribed type ceramic disk with a rough surface roughness is used. Therefore, it is desirable that the disk be made of a material such as polyurethane rubber. Undrawn yarn refers to normal spinning conditions (for example, 800
undrawn yarn spun at a speed of ~1500 m/min), and pre-orientated yarn (so-called
POY) etc. Moreover, the cross-sectional shape of the multifilament undrawn yarn used in the present invention may be a round cross-section or an irregular cross-section of 3 to 8 lobes. In particular, it is a preferable embodiment to use a yarn with an irregular cross section of 3 to 8 lobes, since it is possible to impart a unique luster and feel to the knitted fabric obtained using the yarn. The ratio of the two types of undrawn yarns (A) and (B) to be combined with respect to the total fineness is not particularly specified.
Although it can be designed to obtain the desired hue effect, it is preferably in the range of 1:3 to 3:1. This will be explained in detail below using examples. Example 1 134.2 denier - 36 filament undrawn polyethylene terephthalate yarn (addition of 0.5% TiO ₂ ) (A) wound at a spinning speed of 3000 m/min and a spinning speed of 3000 m/min.
Polyethylene terephthalate (added with 0.5% TiO ₂ ) (B) copolymerized with 3.5 weight percent of dimethyl-5-sodium sulfoisophthalate (B) of 133.7 denier 24 filament wound at m/min,
Using the apparatus shown in FIG. 2, the material was stretched and simultaneously subjected to false twisting and wound. The main processing conditions are as follows. Heat fixing device 3 Length (m) 1.5 〃 〃 Temperature (℃) 205 Heat treatment device 7 Length (m) 1.2 〃 〃 Temperature (℃) 180 Doubling control device 7mmφ separate pin (surface roughness
7S) False twisting device 3-axis external friction false twisting device Equipped with 8 urethane rubber discs Stretching ratio (times) 1.75 Overfeed of 7 during heat treatment (%) 8.0 Number of false twists (T/m) 2370 2nd roller 6 laps Speed (m/min) 400.0 The obtained yarn was knitted (circular knitted) and then dyed under the following conditions. <Dyeing conditions> Dye: Malachite green 5% Owf Glacial acetic acid 0.5 cc/ Sodium acetic acid 0.15 g/ Bath ratio 1:100 Dyeing temperature (°C) 120 Time (min) 60 The knitted fabric is dark green and white with fine marbling. are mixed,
A product exhibiting a pale green intermediate color was obtained. (Thread
(B) is dyed dark green, while thread (A) remains white with almost no dyeing. ) Example 2 Undrawn yarn (A) of Example 1 and spinning speed of 3000 m/mi
An undrawn polyethylene terephthalate yarn (B) to which 2.5 weight percent of carbon black of 137.0 denier 36 filament was added, which was wound at a speed of 137.0 denier, was subjected to stretching and simultaneous false twisting using the apparatus shown in FIG. 2 under the following conditions. Each of the obtained yarns was knitted (circular knitted) and the color tone of the knitted fabric was examined. Summary of results first
Shown in the table.

[Table] Methods and tests that make Test No. 1 the invention
Nos. 2, 3 and 4 are comparative examples. From Table 1, it can be seen that the mixed fibers of Test No. 1 had an excellent dispersion state and a fine black and white marbling, and the desired neutral color effect was obtained. Test Nos. 2, 3, and 4 are all gray overall, but 1 to 5
Black and white stripes of about mm size were present alternately over the entire surface, indicating that the two component systems were insufficiently dispersed.

[Brief explanation of the drawing]

FIGS. 1A and 1B are explanatory diagrams of a state in which two yarns are combined, and FIG. 2 is a diagram of a drawing false twisting process showing an example of an embodiment of the present invention. 1: Feed roller, 2: Doubling regulation device, 3:
Heat fixing device, 4: cooling plate, 5: friction false twisting device,
6: Second roller, 7: Heat treatment device, 8: Third roller, 9: Winding device, 10: Guide, 11,1
1': Undrawn yarn package (A), (B).

Claims (1)

[Claims] 1. When two types of thermoplastic multifilament undrawn yarns (A) and (B), which have different dyeability, are combined and subjected to stretching and false twisting at the same time, the two yarns are separated and separated using a feed roller. A doubling control device is installed at a position between the feed roller and the heat fixing device where the two types of multifilaments are in an unstretched state, and the two types of multifilament undrawn yarns are controlled toward the starting point of false twisting. 1. A method for producing a mixed fiber yarn, which comprises doubling the yarns so that the yarn entry angles are substantially the same, and performing friction false twisting while heat-setting at a temperature at which the multifilaments do not fuse.