JP2570319B2 - Acrylic fiber with a new feel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an acrylic fiber having a novel feeling, particularly two or more acrylic polymers having different copolymer compositions (hereinafter referred to as acrylic polymer). The present invention relates to an acrylic fiber having a hemp-like dry touch feeling based on micro crimps having a multilayer structure.

[Prior Art] Conventionally, micro crimped acrylic fibers are known. For example, Japanese Patent Application Laid-Open No. Sho 54-68417 discloses a single fiber fineness obtained by compound spinning two or more types of acrylic polymers having different heat shrinkage ratios as an acrylic fiber having a hemp-like dry touch feeling. Acrylic fibers having a micro-crimp in the range of 1.5 to 0.5 denier and 40 to 150 per 25 mm of fiber length are known.

However, as shown in FIG. 3, this kind of micro-crimp fiber could only obtain a crimp having a very low degree of crimp with respect to the number of crimps, and the micro-crimp itself was very easy to be crimped. The product had a drawback that the texture of the hemp-like dry touch disappeared in a short time.

[Problems to be Solved by the Invention] The micro-crimp characteristics, which are problems in improving the feeling by the micro-crimping of the acrylic fiber, particularly, the crimp degree of the micro-crimp fiber is low and the micro-crimp itself is poor. The above problem can be solved at once by applying the multi-layered composite technology of acrylic fiber (Japanese Patent Application No. 62-170742) proposed by the present inventors to solve the problem of very easy setting. The inventors have found that the present invention can be performed, and have reached the present invention.

That is, the object of the present invention is to improve the hand feeling by micro-crimping the acrylic fiber, which is a problem of micro-crimp characteristics, especially the crimping degree of the micro-crimp is low and the micro-crimp itself is very easy to settle. To improve the durability of hemp-like dry touch feeling.

[Means for Solving the Problems] An object of the present invention is to provide one component of two kinds of acrylic polymers having different copolymer compositions and a difference in the amount of copolymer components of 2 to 10 mol%. The polymer has a multi-layer composite structure in which the number of layers is joined asymmetrically along the fiber axis direction so as to form a part of the fiber surface in another component polymer so as to form a part of the fiber surface, and It can be achieved by a novel textured acrylic fiber having an expressed number of crimps of 40 or more fibers / inch, an expressed degree of crimp of 35% or more, and a crimp onset retention of 50% or more.

That is, the multilayer structure in the fiber of the present invention is the first structure.
As shown in the cross-sectional view of the micro-crimp fiber shown in the figure, of the two or more types of component polymers constituting the micro-crimp fiber, one component polymer is distributed in one or more layers in another component polymer, and this distribution is performed. This means that the polymer forms a part of the fiber surface and has a continuous structure along the fiber axis direction.

Such a multilayer composite structure is extremely effective in increasing the degree of crimp of latent or actual micro-crimp and the retention of crimp development when adopting a crimp development treatment and a re-stretching treatment as described later. It is.

That is, the micro-crimp fiber of the present invention is composed of two or more types of component polymers, is formed by laminating one component polymer and another component polymer, and the number of layers exceeds two layers, preferably 4 to 15 layers,
More preferably, a structure in which the component polymers are continuous along the fiber axis direction is formed so as to have 8 to 12 layers.

Further, the micro-crimp fiber of the present invention has an expressed crimp count of the fiber of 40 peaks / inch or more, preferably 45 to 70 peaks / inch,
It is necessary to maintain a well-balanced crimp development degree of 35% or more, preferably 40 to 60%, and a crimp expression retention of 50% or more, preferably 60% or more. The reason is that the number of expressed crimps of the fiber is smaller than 40 peaks / inch,
When the expressed degree of crimp is smaller than 35%, hemp-like dry touch feeling is not sufficiently imparted to the textile product, which is a fatal defect for textile materials for spring and summer.

Further, the micro-crimp fiber of the present invention has a
If it is less than 50%, for example, in bulking in the dyeing step, the degree of crimp development changes according to the binding force in the spun yarn, and especially, even if the number of crimps to be developed increases, the degree of crimping is expected. Since the shrinkage does not increase and the crimping force fluctuates, the hemp-like feeling effect is hard to be realized, which does not meet the purpose of the present invention.

The number of expressed crimps, the degree of expressed crimps, and the retention of crimp expression are defined as follows.

Number of expressed crimps: According to JIS-L1015.

A predetermined load (2 mg / d) was hung on each of 40 samples collected from the test fiber bundle that had been subjected to boiling water treatment, and the single fiber length was 50 m.
Fix the length of m on the slide glass. Create an enlarged projection with a photo magnifier and count the number of crimps per 25mm.

Expression crimp degree: Measure with a crimp measuring machine according to JIS-L1015.

Crimp onset retention: 0.2 mg / d (0.4 g) for 2,000 denier subtows of length A
, A boiling water treatment (98 ° C. × 20 minutes), cooling, drying (65 ° C. × 60 minutes), measuring the length (the length at this time is B), and shrinkage according to the formula (I). (ΔS1) is calculated.

ΔS1 (%) = {(AB) / A} × 100 (I) A: length of original sample B: length after treatment On the other hand, 1.5 mg / d for 2,000 denier subtow of length A
Apply a load of (3 g), perform boiling water treatment (98 ° C x 20 minutes), cool, dry (65 ° C x 60 minutes), measure the length (the length at this time is C), and formula (II) Is calculated according to the following equation.

ΔS2 (%) = {(AC) / A} × 100 (II) A: Length of original sample C: Length after treatment From the thus obtained ΔS1 and ΔS2, crimp according to the following formula The expression retention is calculated.

Next, a production example of the fiber of the present invention will be described.

That is, for the fiber of the present invention, for example, a spinning solution of two or more acrylic polymers having different copolymer compositions is led to a multi-layering apparatus, and the number of theoretical layers in a single yarn defined by the following formula is set to be about 6 or more. After splitting, it is introduced into a coagulation bath from a spinneret to form a coagulated yarn. Next, after the coagulated yarn is dried and densified, a micro-crimp expression treatment and a re-drawing treatment are performed, whereby desired micro-crimp fibers can be obtained.

In the above equation, K is a constant determined by the outer shape of the spinneret. The value of K is 1 for a square die, and the value of K is 1.1 for a circular die.

As the acrylic polymer in this case, a known acrylic polymer having a fiber-forming property, that is, a modacrylic polymer containing 30% by mole or more of acrylonitrile (hereinafter, abbreviated as AN) or 80% by mole or more of AN is used. As long as it is an acrylic polymer and a copolymer thereof to be contained, it is not particularly limited, but when two or more polymers are selected from the aspect of microcrimp characteristics as a composite component polymer in microcrimp fibers, the It is desirable that the difference in the amount of the copolymer components is about 2 to 10 mol%, preferably 3 to 7 mol%. If the difference in the copolymerization amount is less than 2 mol%, the crimp development performance is insufficient, while if it exceeds 10 mol%, the hand of the micro-crimp fiber becomes coarse and hard, and spots are easily generated. Tend.

In addition, copolymer components of the acrylic polymer include, for example, vinyl acids such as acrylic acid, methacrylic acid and their lower alkyl esters, itaconic acid, acrylamide, methacrylamide, vinyl acetate, vinyl chloride, styrene, and vinylidene chloride. In addition to the compounds, the same or different kinds of acidic monomers such as unsaturated sulfonic acids such as vinyl sulfonic acid, allyl sulfonic acid, methallyl sulfonic acid, p-styrene sulfonic acid and salts thereof can be used.

The acrylic polymer is dimethylformamide, dimethylacetamide, dimethylsulfoxide (hereinafter referred to as DM
SO, abbreviations, etc., rhodan lithium, rhodan potassium,
It is appropriately dissolved in an organic solvent or an inorganic solvent such as a rhodan salt of an alkali metal such as rhodan sodium, rhodan ammonium, zinc chloride, or a perchlorate to obtain a spinning dope having a polymer concentration of about 10 to 25% by weight.

The spinning solution of the composite component polymer is supplied to a multi-layering device, where it is divided into layers, where the layer is divided into a predetermined number of theoretical layers in a single yarn, and then discharged from a spinneret into a coagulation bath, or a wet spinning method. Once discharged from the die into air or an inert atmosphere, the fibers are formed into fibers by a dry-wet spinning method or the like introduced into a coagulation bath.

FIG. 4 is a flow sheet for making it easier to understand the process requirements of the fiber production stage of the fiber of the present invention. In the figure, A and B are spinning solutions of the composite component polymer, 1 is a guide device for individually flowing the spinning solution of the composite component polymer, 2 is a multilayering device,
3 is a filter, 4 is a spinneret, 5 is a micro-crimp developing step of the fiber yarn, and 6 is a re-drawing step for once removing the micro-crimp developed in the micro-crimp developing step 5.

What should be particularly noted at the stage of producing the fiber of the present invention is as follows.
First, the spinning solution of the composite component polymers A and B is sufficiently and stably divided into layers by the multi-layering device 2, and the multi-layered state once formed is stably maintained until the spinneret 4.

That is, in order to achieve sufficient multilayering in the multilayering apparatus 2, the number of theoretical layers in a single yarn is divided into about 6 or more, preferably 6 to 20, more preferably 7 to 12, and then the single spinning is performed. That is to introduce into the base 4.

The theoretical number of layers in a single yarn is appropriately determined according to the structure in the multilayering device 2, that is, the number and arrangement of the stacking layers of the multilayering element 2 ′, the twist angle of the torsion blade, the number of passage tubes, the number of holes in the spinneret 4, and the like. What is necessary is to control.

In order to stably multiply such a multicomponent spinning solution in a multilayering apparatus, the viscosity difference between the spinning solutions is reduced by 60%.
The temperature should be 50 poise or less at 60 ° C, preferably 30 poise or less at 60 ° C. By setting the viscosity difference to 50 poises or less, streamlines are less likely to be disturbed in the multi-layering device 2, and the multi-layer state divided into layers is more stabilized.

Also, when supplying the spinning solutions A and B to the multilayering device, the spinning solutions A and B are not mixed with each other, instead of once being combined with the spinning solution of the composite component polymer and then supplied to the multilayering device. As shown in FIG. 4, it is desirable that the spinning dope A and B are individually flowed in by the undiluted solution guiding device 1 provided at the inlet of the multilayering device. Such a spinning solution inflow means makes the multilayering in the multilayering apparatus more reliable and stable.

Further, as shown in FIG. 5, the multi-layering device 2 sets the pitch (L / D) of the multi-layering element 2 'to 0.8 to 2.5, especially 1.4 to 2.0.
It is desirable to be within the range. When the pitch deviates from 0.8 to 2.5, the multilayered spinning solution A,
The streamlines of B are easily disturbed and mixed, and the multi-layered state becomes unstable, which is likely to result.

The multilayering device 2 used here includes, for example, Toray Industries, Inc.
"Hi-Mixer" manufactured by Noritake Co., Ltd., "Skeya Mixer" manufactured by Sakura Seisakusho Co., Ltd., and "Ros ISG Mixer" manufactured by Tokushu Kikoki Co., Ltd.

Among these multi-layering apparatuses, the constituent elements are not complicated, the flow resistance of the spinning dope is relatively small, and the change in the effective area in the flow path of the spinning dope is small. In other words, the abnormal retention of the spinning dope in the apparatus. A "static mixer" and a "skewer mixer", which are less likely to cause cracks, are preferably used.

The spinning stock solutions A and B divided into layers in a predetermined range by the multilayering device 2 are guided to a normal spinneret 4.
The opening between the multilayering device 2 and the spinneret 4 is 10 μm.
As described above, it is desirable to interpose a filter of preferably 20 to 50 μm. That is, as the opening of the filter 3 becomes smaller, the filter effect or spinnability of the spinning stock solution is improved, but on the other hand, the spinning stock solution is divided into layers by the above-mentioned multilayering device due to the mixing or disturbing effect of the filter. Is no longer possible.

The filter medium of the filter 3 is suitably made of a gauze fabric such as polyester or polyamide, or a lattice-like material such as a stainless steel wire mesh.

The spinning solution passed through the filter 3 is discharged from the spinneret 4 into a coagulation bath using an aqueous solution of the organic solvent or the inorganic solvent as a coagulant to form coagulated yarn (not shown). At this time, the polymer solution discharged from the spinneret 4 may be directly introduced into the coagulation bath (wet spinning method), or the spinneret 4 may be used.
Is provided at a position of about 2 to 20 mm above the liquid surface of the coagulation bath, and the polymer solution discharged from the spinneret is caused to travel in a minute space between the spinneret hole and the coagulation liquid surface. A so-called dry-wet spinning method may be employed. Of course, the fiber of the present invention can also be obtained by a dry spinning method.

The coagulated yarn derived from the coagulation bath is stretched at the same time as washing or washing with water, stretched, washed with water, or stretched after washing, and then dried and densified. The micro-crimp developing process and the re-stretching process in the crimp developing process 5 and the re-stretching process 6 are indispensable.

That is, the micro-crimp development treatment is performed in a relaxed state under steaming, and the steaming heat treatment temperature at that time is desirably 110 ° C. or more, particularly preferably 115 to 130 ° C. By the steaming heat treatment in the relaxed state, as shown in FIG. 2, the latent micro-crimp of the fiber yarn can be sufficiently developed.

In addition, the re-stretching process makes the crimp developed in the previous micro-crimp development process latent again, thereby smoothly spinning and commercializing the micro-crimp fiber and, at the same time, realizing the micro-crimp during the commercialization. Although it is carried out to further accelerate the stretching, it is preferable that the stretching is performed at a temperature lower than the heat treatment temperature at the time of the micro-crimp development treatment, and the stretching is usually performed under a wet heat or steaming temperature of 80 to 115 ° C. Magnification is in the range of 1.05 to 1.50.

Thus, in the present invention, the number of theoretical layers in a single yarn is about 6
With respect to the above-described multilayered coagulated yarn, the fibers obtained, in particular, the single fiber fineness is about 5 denier or less, preferably 3.5 to 3.5 denier, by integrally combining the micro-crimp development treatment and the redrawing treatment under predetermined conditions. Depending on the intended micro-crimp and its crimp properties, 1.2 denier fibers will have a particularly durable hemp-like dry touch feel.

Hereinafter, the present invention will be described more specifically with reference to examples.

 In this example, the hand and the degree of leveling were determined as follows.

Hand: A 4th spun roving was prepared from the test fibers. This roving was bulked in steam (100 ° C. × 10 minutes), and after drying, the bulkiness and the dry touch feeling were evaluated. This was used as a measure of the bulkiness of the spun yarn after dyeing (the appearance of crimping under constraint) and the dry touch feeling.

◎; Very good ○; Good △; Slightly good ×; Poor XX; Very poor Level of dyeing: Three kinds of dyeing speeds differing from the standard test and the test fiber using a package dyeing machine as shown below. Dye in the same bath with dye at 100 ° C for 60 minutes.

Staining conditions: Astrazon Golden Yellow GL 1.0% owf Maxilon Red 0.5% owf Malachite Green 0.22% owf Katiogen L 0.5% owf Sodium acetate 0.5% owf pH = 4 2 g of each of the obtained fiber bundles after dyeing was collected and 10 g
After cutting to 2 mm, the color tone difference and density difference of the opened raw cotton are visually judged at intervals of 0.2 under daylight, and the dye difference between the maximum value and the minimum value of the color tone and density is evaluated as the level of uniform dyeing. The one without dyeing difference is the best, and when it is 2.0 or more, uneven dyeing in the fiber bundle is clearly seen.

Here, the standard fiber is a fiber obtained by mixing a spinning solution obtained by almost completely mixing composite polymers having different copolymerization compositions into a single polymer under the same spinning conditions as the fiber of the present invention. .

Example 1 96.6 mol% of AN, 4.0 mol% of methyl acrylate, and 0.4 mol% of sodium methallylsulfonate were solution-polymerized in DMSO, and a spinning stock solution (A) having a solution viscosity of 140 poise / 60 ° C and a concentration of 22.3 wt% was used. Was prepared.

On the other hand, 91.2 mol% of AN, 8.5 mol% of methyl acrylate and 0.3 mol% of sodium methallylsulfonate were similarly solution-polymerized to give a spinning solution (B) having a solution viscosity of 135 poise / 60 ° C and a polymer concentration of 22.2% by weight. Was prepared.

(A) and (B) Equivalent amounts of the two kinds of spinning dope were measured using a "static mixer" (pitch diameter L / D 1.5 of a multilayer element) equipped with a stock solution inlet guide device 1 as shown in FIG.
Through a filter made of polyester gauze woven fabric (opening: approx. 30μ) provided in the immediate vicinity of the spinneret, from a square single spinneret with a hole diameter of 0.065mmφ to 55% by weight, 30 ° C DMSO. Discharged into coagulation bath using aqueous solution as coagulation liquid
It was a coagulated yarn. At this time, the number of layers of the multilayer element and the number of holes in the spinneret were controlled to obtain the theoretical number of layers in a single yarn as shown in Table 1.

The coagulated yarn was drawn 6.5 times in hot water at 98 ° C., and the drawn yarn was sufficiently washed with warm water and then dried and densified at 165 ° C.

The dried and densified yarn was subsequently subjected to a micro-crimp development treatment in a relaxed state during steaming at 120 ° C.

Next, the yarn after the micro-crimp development treatment was stretched again at a steaming temperature of 102 ° C. at a magnification of 1.18 times to eliminate the micro-crimp, and was further machined by an indentation type crimping machine to about 10 ridges / 25 mm. Apply crimp and dry with hot air at 65 ° C.
A denier micro crimp fiber was obtained.

The resulting fibers were examined for the number of expressed crimps, the degree of expressed crimp, the retention of crimp expression, the degree of uniform dyeing and the feeling, and the results are shown in Table 1.

As shown by the results, the fiber of the present invention has a multilayer structure in which the component polymer has more than two layers along the fiber axis direction, so that there is no uneven dyeing, and a very dry touch due to a large number of micro-crimps having a high degree of crimp. It can be seen that it has a new texture rich in bulkiness.

Example 2 In Example 1, the conditions of the micro-crimp development treatment for the dried and densified yarn were changed as shown in Table 2. Otherwise, a micro-crimp fiber was obtained in the same manner as in Example 1 (however, the number of theoretical layers in a single yarn in this case was 9.3).

Table 2 shows the number of expressed crimps, the degree of expressed crimp, the degree of retention of crimp development, the level of uniform dyeing, and the feeling of the obtained fibers.

Example 3 In Example 1, the redrawing conditions after the micro-crimp development treatment for the dry densified yarn were changed as shown in Table 3. Otherwise, in the same manner as in Example 1, the fineness of single fiber
2.5 denier micro crimp fiber was obtained (however, the theoretical number of layers in a single yarn in this case was 9.3).

Table 3 shows the number of expressed crimps, the degree of expressed crimp, the degree of retention of crimp expression, the level of uniform dyeing, and the feeling of the obtained fibers.

[Effects of the Invention] According to the acrylic micro-crimp fiber of the present invention as described above, the micro-crimp characteristic which is a problem in improving the hand by micro-crimping the conventional acrylic fiber, particularly, the degree of crimp developed The point of low crimp and very easy crimping has been eliminated, and therefore a hemp-like dry touch and a crisp feeling are required. For example, in the field of spring and summer clothing such as sweaters and sports socks. It has a remarkable effect.

[Brief description of the drawings]

FIG. 1 is a cross-sectional photograph of a micro-crimp fiber according to the present invention, FIG. 2 is a schematic view showing a crimp state of the micro-crimp fiber according to the present invention, and FIG. 3 is a schematic view showing a crimp state of a conventional micro-crimp fiber. FIG. 4 is a flow sheet in the stage of spinning the fiber of the present invention, and FIG. 5 is a schematic view of a multilayer element in the multilayer apparatus shown in FIG. A, B: Composite component polymer spinning solution 1: Composite component polymer guide device 2: Multilayer device, 2 ': Multilayer element 3: Filter 4: Spinneret 5: Micro-crimp development process of fiber yarn 6: Micro Redrawing process of crimp-expressing fiber D: Diameter of multilayer element L: Length of one multilayer element

Claims (1)

(57) [Claims] 1. A two-component acrylic polymer having a different copolymerization composition and a difference in the amount of copolymerized components of 2 to 10 mol% is incorporated into another component polymer, and the fiber surface The number of layers is asymmetrical along the fiber axis direction to form a part and the number of layers is two.
Novel having a multi-layer composite structure joined beyond the layers and having an expressed fiber crimp count of 40 ridges / inch or more, an expressed crimp degree of 35% or more, and a crimp onset retention of 50% or more Acrylic fiber with a good texture.