JPH0797776A - New microfiber knit fabric - Google Patents

Abstract

PURPOSE:To provide new microfiber knit fabric having a new, extremely natural and good touch by using thick and thin conjugate fibers each comprising the combination of mutually incompatible polymers. CONSTITUTION:A microfiber knit fabric comprising conjugate fibers each consisting of at least two kinds of mutually incompatible polymer components, the polymer components being alternately disposed in the cross-sectional direction of the fiber, the fiber having thick parts and thin parts in its longitudinal direction, the respective components of the conjugate fiber being opened and fibrillated, and the thick parts of the conjugate fiber being dyed in a deeper color than other parts to give a score-like pattern appearance, and its production method.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microfiber knitting having a novel streak appearance and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, many knitted fabrics using microfibers have been proposed.

For example, JP-A-52-27822 and JP-B-53-3
5633, JP 61-282445, JP 62-8535
Japanese Patent Laid-Open No. 60-215869, Japanese Patent Laid-Open No. 61-34276, and the like propose composite fibers and fine fibers mainly composed of polyester / nylon. However, in the above-mentioned conventionally proposed method, only fibers having a too uniform shape are obtained, and therefore, the knitting has a natural appearance and a natural texture produced from the natural appearance. Couldn't get.

[0004]

The present inventors have arrived at the present invention as a result of earnest research. That is, an object of the present invention is to obtain a microfiber knitted fabric having a novel streak-shaped light and shade portion which has not been achieved conventionally, and another object is to industrially produce a microfiber knitted fabric having a novel streak-shaped light and shade portion which has not been conventionally found. An object is to provide a method of easily and inexpensively manufacturing.

[0005]

The present invention comprises at least two kinds of polymer components which are incompatible with each other and which are alternately arranged in the transverse direction of the fiber, and which has a thick portion (hereinafter T). Part) and a thin portion (hereinafter referred to as t part), which is a knitted fabric, and the composite fiber is opened and fibrillated into each component forming the composite fiber,
Further, it is a microfiber knitted fabric in which the T portion of the composite fiber is dyed darker than other portions and has a streak-like appearance.

The fiber of the present invention is a composite fiber composed of at least two different polymers which are incompatible with each other. The phrase “incompatible with each other” means that when the polymers are mixed in a molten state, they are merely mixed without being dissolved and forming a uniform phase. When the substances which are incompatible with each other are mixed, the mixture generally becomes cloudy. Further, even if the mixture is not clouded, each phase can be confirmed when the mixture is observed with a different phase contrast microscope or an electron microscope. Alternatively, when the mixture is subjected to thermal analysis by differential calorimetry, mutual melting points are observed.

As an example, combinations of polyester with polyamide, polyurethane, polyacrylonitrile, polyethylene, polypropylene etc. are incompatible with each other. Similarly, polyamide is incompatible with polyester, polypropylene, polyethylene, polytetrafluoroethylene, polyacrylonitrile and the like. Alternatively, many other combinations are incompatible with each other. More specifically, for example, as the polyamide component, nylon 4, nylon 6, nylon 7, nylon 11, nylon 1
2. Nylon 66, nylon 610, polymethaxylene adipamide, polyparaxylylene decanamide, polybiscyclohexylmethane decanamide, and copolyamides containing them are well known. As the polyester, polyethylene terephthalate, polytetramethylene terephthalate, polyethyleneoxybenzoate, poly 1,4-dimethylcyclohexane terephthalate,
Polypivalolactone and copolyesters containing them are well known.

The composite fiber is composed of a combination of polymers having poor mutual affinity as proposed in Japanese Patent Publication No. 62-8535, Japanese Patent Publication No. 52-27822, and Japanese Patent Publication No. 61-282445. Although a thing can be used, a thing with other shapes can also be used. One example is shown in FIG. Among them, b, e (radial), f (radial), h (radial) in FIG.
Preferred are k and n (hollow ring). In particular, a combination of polymers in which one component contracts extremely greatly with a specific organic solvent such as benzyl alcohol described in JP-B-53-35633 is preferable. A combination of polyester and polyamide is particularly preferable.

The ratio of the two polymers according to the invention is usually 5 /
1 to 1/5 (weight ratio), preferably 3/1 to 1 /
3 (weight ratio). In a special case, it may be out of this range. For example, in the case of a combination of nylon and polyester, nylon easily contracts during the peeling treatment. Therefore, the ratio of nylon component / polyester component is preferably 2/1 to 1/3, more preferably 1/1 to 1/2.

The conjugate fiber of the present invention can be produced by a usual method for producing a conjugate fiber. The denier of the single yarn before opening and fibrillation is preferably about 1 to 10 denier, more preferably 2 to 5 denier. The denier of each component (after opening and fibrillation) constituting the composite fiber is at most 1 denier, preferably at most 0.5 denier, more preferably 0.2 to 0.05 denier. The denier of each fibril after opening and fibrillating each filament may be the same or different.

If the denier of the fiber before opening and fibrillation is less than 1 denier, there is a problem in terms of operability. On the other hand, if it exceeds 10 denier, the denier after opening of each component becomes large, and there is a possibility that the characteristic performance and texture of the target microfiber may not be obtained.

The T portion & t portion (hereinafter referred to as thick and thin) referred to in the present invention means that the denier is discontinuous in the fiber axis direction. Usually, the ratio of the cross-sectional areas of the T portion and the t portion is at least 1.5, more preferably at least 2, and particularly preferably 2.5 to 10. The length of the T portion is preferably at least 3 mm or more, more preferably at least 5 mm or more, particularly preferably 10 to 50 mm. Moreover, it is natural that the frequency of appearance of the T part varies, but it is usually 30
1 or more per cm, preferably 1 or more per 20 cm,
More preferably, it is 1 or more per 10 cm. The ratio of the T portion to the whole fiber is usually at least 2%, preferably at least 5%, more preferably 10 to 60%. When the T portion is a multifilament, it is preferable that the phases are the same as much as possible. That is, it is preferable for clarifying the color difference and improving the feeling of fluffiness and the touch.

Any method may be used to make sick and thin, but the most common method is to draw an undrawn yarn at a draw ratio lower than the natural draw ratio. The natural draw ratio refers to a draw ratio at which, when a yarn after spinning is applied, the drawing proceeds by necking and the entire yarn becomes a completely drawn yarn. For example, a fiber wound at a spinning speed of 1200 m / min usually has a natural draw ratio of about 3.5 to 4.0. Therefore, if the draw ratio is smaller than that value, the undrawn part remains in the fiber and the thick and thin It becomes a thread. The lower the draw ratio than the natural draw ratio, the easier the thick and thin film appears and the more noticeable the difference between the T and t parts. How to select the stretching conditions (stretch ratio, stretching temperature, set temperature) depends on what polymer was used, what spinning speed was used, and what form of thick and thin was desired. . It is necessary to select the optimum conditions according to the purpose and conditions.

The knitting used in the present invention may be either weft knitting or warp knitting. For example, the wefts include a structure typified by plain knitting, rubber knitting, pearl knitting, and the like, and variations thereof, and the warp knitting includes a structure typified by denby knitting, cord knitting, atlas knitting, and the like.

The yarns of the present invention may be used in 100% knits or alternatively or every few yarns. Naturally, it is necessary to change the ratio to be used depending on the purpose such as how much surface change the product has and what kind of pattern is formed.

[0016] In knitting using microfibers, a patterning which pays attention to the difference in dyeing property due to sick and thin formation of the composite fiber having the solution opening ability as proposed in the present invention has been proposed so far. No, it is extremely large in commercial value. The light and shade of the color of the thick and thin portion may be such that it can be clearly discriminated visually. Moreover, regarding the texture, there is a feel like that of a cloth that has been subjected to a raising treatment without the raising treatment.

The patterning, which pays attention to the difference in the dyeability of these so-called microfiber raw yarns due to thick and thin, has not been proposed so far, and has an extremely large commercial value. The lightness and darkness of the color of the T portion and the t portion may be such that they can be clearly discriminated visually. For example CIE
The ΔL value of the standard color system is about 2 or more. Moreover, regarding the texture, there is a feel like that of a cloth that has been subjected to a raising treatment without the raising treatment.

However, by further raising the fabric of the present invention such as sanding, a peach-skin-like or suede-like texture and surface feeling can be further developed.

That is, the fiber has an unstretched portion (T
Parts) and stretched parts (t parts) are present alternately, and the fiber diameter ratio is at least 1.5 or more, preferably 2 or more, and more preferably 2.5 to 7, so that opening and fibrillation are performed. The shrinkage rate and elongation rate of the subsequent fibers are different, and as a result, a large loop is formed on the fabric surface due to the difference in the yarn length, and the loop just gives a feeling of raising the surface by sanding treatment or the like.

In the method of the present invention, at least two kinds of polymer components which are incompatible with each other are alternately arranged in the cross-sectional direction of the fiber, spun, and drawn at a natural draw ratio or less. A knitted fabric using a composite fiber having 10 parts and a t part is formed, and then each component of the composite fiber is subjected to a process of peeling and fibrillating, and then the T part of the composite fiber is dyed in a darker color than the t part. Characterized by dyeing.

The spinning method is not particularly limited as long as it is a method for producing the above-mentioned composite fiber. For example, composite spinning of nylon component and polyester component at a discharge rate of 1/2,
It is easy to obtain a fiber having a cross section as shown in FIG. The spinning speed is usually 700 m / min or more. When the winding speed is about 700 to 2000 m / min, undrawn yarn having a low orientation state can be obtained. The unstretched yarn is stretched to give the strength and elongation of the yarn that can withstand the normal specifications, but the feature here is that the unstretched part is left in a part of the fiber without being completely stretched. For this purpose, the draw ratio is lower than the natural draw ratio of the undrawn yarn. Usually, the natural stretching ratio is 0.95 times at most, preferably 0.90 times at most, and preferably 0.65 to 0.85 times. If the draw ratio exceeds 0.95 times the natural draw ratio at most, the target thick and thin becomes unclear. The stretching temperature is usually near the glass transition point of the polymer,
Preferably glass transition point −10 ° C. to glass transition point +10
It is carried out at a temperature of ℃, and the phase generated at the T part is made to match as much as possible.

When the spinning speed is more than 2000 m / min, the fibers after spinning form a partially oriented state (POY), and in this POY yarn as well, sick and thin is formed by lowering the draw ratio. I can do things.

By leaving the yarn for a while after spinning, for example, for one day or more, preferably for two days or more (aging), thick and thin can be clearly formed during drawing.

The conjugate fiber obtained after drawing may be used as it is as a raw yarn or may be used as a processed yarn such as false twist.

For knitting, 100% of the composite fiber may be used, or interlace with other yarn may be used. By interlacing with other threads, the size of the Kasuri pattern in the product can be changed relatively freely. Further, a mixed yarn of the composite fiber and another fiber may be used.

After knitting, one of the composite fibers is treated with a chemical for swelling to open and fibrillate each component of the composite fiber. For example, in the case of a composite fiber composed of nylon and polyester, it is more efficient and less expensive to use a chemical that swells nylon. For example,
The knitted fabric is immersed in an emulsified water dispersion liquid of benzyl alcohol, phenylethyl alcohol, phenol or the like, and then washed with warm water. During this treatment, the nylon component of the composite fiber swells and shrinks in the solvent, and the fibers are opened and fibrillated between the polyester components having poor compatibility. As the nylon component shrinks, the polyester component floats up, forming loops on the fabric surface. The expression of this loop further enhances the knitted fabric's fluffiness and wearability. The number of loops is proportional to the amount of the composite fiber used, and the size of the loops can be controlled by the amount of tension applied to the knitted fabric during processing.

For dyeing, both fibers forming the conjugate fiber can be dyed, but it is also possible to dye only one fibril by using a dye having an affinity for one of the components. If dyes of different colors having affinity for both components forming the composite fiber are used, a special deep dyeing effect is exhibited.

After dyeing, it is not a particular problem to add generally hydrophilic treatment, water repellent treatment, antistatic treatment, antifouling treatment and the like.

The present invention will be described in more detail below with reference to examples, but the present invention is not limited thereto.

Example 1 Intrinsic viscosity ([η]) of 0.64 measured at 20 ° C. using a solvent of phenol / tetrachloroethane (6/4)
Nylon 6 having a relative viscosity of 2.85 measured at 25 ° C. at a polymer concentration of 1 g / dl using polyethylene terephthalate and concentrated sulfuric acid solvent was spun at a composite ratio of 1: 2 to obtain the composite fiber shown in FIG. 1f. Obtained. Spinning speed is 900m / min,
The stretching conditions were 65 ° C. and 2.65 times. Thick and thin were clearly expressed in the drawn yarn, and the ratio of denier in the T part to denier in the t part was about 5 times. The length of the T portion was about 5 to 30 mm, and the frequency of expression was about 3 per 10 cm. 100% of this fiber was used and knitted at 40 gauge to make a smooth knitted fabric having a density of wale / course = 52/65 (/ inch).

Then, after immersing in a water emulsion of 20% benzyl alcohol, washing was carried out in warm water at 60 ° C. A knit having a density of wale / course = 83/83 (/ inch) was obtained by shrinking about 30% in the machine direction and about 30% in the machine direction during this process.

Dyeing was carried out using a jet dyeing machine. Disperse dye (CIDisperse Blue 270 5%, CIDisperse Red 828
1%) was dyed at 130 ° C. for 30 minutes, then immersed in an aqueous 4% tannic acid solution at 80 ° C. for 20 minutes, washed and dried to obtain a knit.

In the obtained knitting of the knitting, a light and shade stripe pattern was clearly confirmed. In addition, it had a peach-skin touch, which was a very smooth touch. Each component of the composite fiber was opened and fibrillated, and the difference in yarn length between the fibrils was large, and the fluffiness was excellent.

As a comparative example, the stretching conditions are 65 ° C.,
Samples were taken as 3.95 times. The fiber was stretched uniformly and showed no thick and thin. Knitting was performed and dyeing was performed in the same steps and conditions as above. The fabric did not have a particularly clear streak pattern and had no special texture.

Example 2 Using the same polymer combination as in Example 1, FIG.
A composite fiber having a cross section of b, h, k was obtained. Next, knitting and processing were performed in the same manner as in Example 1 to obtain a knit. The obtained fabric had a streak-like appearance and a peach skin touch texture. The conjugate fiber of FIG. 1k had a remarkable effect of the loop of the ultrafine fibers and had a peach skin touch to suede touch appearance and texture.

[0035]

EFFECTS OF THE INVENTION According to the present invention, the microfiber knitting, which has had only a very artificial and very uniform surface state until now, has a special appearance and state even without relying on a special dyeing method such as printing. Like Further, in the print, only a certain repetitive pattern can be applied, but in the present invention, a completely random non-repeating pattern can be expressed, which gives the cloth a very natural feeling. In addition, it is possible to have a feeling of fluffiness and a special touch without feeling sanding or raising treatment. That is, there is a great industrial advantage that a completely new surface state that has never existed can be obtained very easily and at very low cost.

[Brief description of drawings]

FIG. 1 shows an example of a cross-sectional shape of a composite fiber that can be used in the present invention. The presence or absence of diagonal lines in the figure indicates different polymers that are incompatible with each other.

Claims (8)

[Claims] 1. A composite fiber comprising at least two types of polymer components which are incompatible with each other and which are alternately arranged in the cross-sectional direction of the fiber, and which has a thick portion and a thin portion in the fiber axis direction. In a knitting, the composite fiber is opened and fibrillated into each component forming the composite fiber, and the thick part of the composite fiber is dyed in a darker color than other parts and has a streak-like appearance. knitting. 2. The knitted fabric according to claim 1, wherein the polymer components are alternately arranged in a hollow ring shape. 3. The knitted fabric according to claim 1, wherein the polymer components are arranged in a radial pattern. 4. The knitted fabric according to claim 1, wherein the ratio of the cross-sectional area between the thick portion and the thin portion of the composite fiber is at least twice or more. 5. The knitted fabric according to claim 1, wherein the length of the thick portion of the composite fiber is at least 3 mm or more. 6. The appearance frequency of the thick portion of the composite fiber is 10 cm.
The knitted fabric according to claim 1, wherein the number of knitted fabrics is at least one. 7. A thick portion in the fiber axial direction obtained by spinning at least two types of polymer components which are incompatible with each other and which are alternately arranged in the cross-sectional direction of the fiber, and drawn at a natural draw ratio or less. A knitting using composite fibers having a thin portion is made, then a process of separating and fibrillating each component of the composite fiber is performed, and then, a thick portion of the composite fiber is dyed in a darker color than a thin portion. A method of manufacturing microfiber knitting that is characterized by the facts. 8. The method according to claim 7, wherein at least the thin portion of the composite fiber is divided under the condition that one component swells.