JPH10266019A - Water-sensitive acrylic conjugate fiber having pill resistance and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a conjugate fiber having excellent pill resistance and crimp- developing force by adjusting a viscosity of a spinning dope of a specific high- shrinkage component and a spinning dope of low-shrinkage component to a specific viscosity, respectively, subjecting these solutions to wet conjugate spinning in side by side type and drawing and drying the spun yarn. SOLUTION: A spinning dope of a high-shrinkage component composed of an acrylonitrile-based copolymer containing 2-6 wt.% methyl acrylate or vinyl acetate and 3-5 wt.% hydrophilic comonomer and a spinning dope of a low shrinkage component composed of an acrylonitrile-based copolymer containing 4-9 wt.% methyl acrylate or vinyl acetate and 0-1 wt.% hydrophilic comonomer are prepared so that these viscosities at 50 deg.C are 50-100 poise. Then, these dopes are subjected to wet conjugate spinning in side by side type to form a fiber. The fiber is oriented at a draw ratio of 3.0-5.0 times in hot water and subjected to drying treatment and relax treatment in saturated steam having 1.3-2.0 kg/cm<2> .G saturated steam pressure to provide the objective fiber having 1.8-2.6 (g/d) tensile strength and 20-35 product of knot strength with knot elongation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water-sensitive acrylic side-by-side type conjugate fiber having excellent anti-pill properties and crimping power.

[0002]

2. Description of the Related Art Conventionally, acrylonitrile-based composite fibers have been industrially produced as textile materials for clothing or carpets due to their excellent crimping properties, sublimeness, and coloring. One of the production methods is to use wool by using at least two kinds of acrylic copolymers having different contents of ionizable groups (hydrophilic groups) such as sulfonic acid groups as composite components constituting fibers. It is known that like water-sensitive fibers can be produced (for example, Japanese Patent Publication No. 38-102).
No. 4, JP-B-57-35288). In the present invention, the term "water sensitivity" refers to a property in which elongation due to water swelling and shrinkage due to drying occur repeatedly, and is sometimes referred to as water reversibility.

[0003]

However, when these water-sensitive acrylic composite fibers are composited in a side-by-side type, the fluffs on the product surface are entangled due to the three-dimensional crimping form peculiar to the composite fibers. It is easy to generate pills. It is well known in the field of clothing and the like that the pill significantly impairs the aesthetics or texture of the product, and measures for it are strongly demanded.

[0004] The basic concept of imparting anti-pill properties at the raw cotton stage of the acrylic fiber is (a) selection of conditions for suppressing entanglement of fluff, which is a main cause of pill generation,
(B) There are two directions: a method in which even if fluff is generated, it is dropped before it forms a pill. The former method is generally disadvantageous in that the method is limited by the structure of the knitted fabric or the morphology of the structure, so that it cannot be expected to develop a wide range of products in practical use. In order to provide a practically advantageous anti-pill property, the latter method, that is, a method in which fluff is removed before the fluff forms a pill, is effective.

[0005] As a specific method for this purpose, for example, it has been attempted to give a negative water sensitivity by employing a low draw ratio (for example, USP, 3038240) and to reduce the strength of the fiber. Although practically desirable anti-pill properties have been obtained by these methods, there are not few examples, but on the other hand, the post-processability decreases due to the decrease in fiber strength, that is, the spinning permeability is poor, especially the generation of fly, the yarn There is still a problem to be solved in that the number of groups is increased and the strength of the spun yarn is reduced, and the quality of the fiber is deteriorated and the high-order workability is impaired.

[0006]

Means for Solving the Problems Water-sensitive acrylic composite fibers of the side-by-side type by wet spinning are widely preferred by consumers in the field of spun knits and the like. The present inventors, for these water-sensitive acrylic composite fibers,
As a result of intensive studies to solve the above problems, the present invention has been achieved.

That is, the acrylic composite fiber of the present invention is characterized in that, in a side-by-side type anti-pill acrylic composite fiber, (a) 2 to 6% by weight of methyl acrylate or vinyl acetate and a hydrophilic comonomer are used. Highly shrinkable components (A) and (b) made of acrylonitrile copolymer containing 3 to 5% by weight of methyl acrylate or vinyl acetate.
A low-shrinkage component (B) comprising an acrylonitrile-based copolymer containing 0 to 9% by weight and a hydrophilic comonomer at 0 to 1% by weight;
And a tensile strength of 1.8 to 2.6 (gram / denier), and a product of knot strength (gram / denier) and knot elongation (%) is 20 to 35. .

According to the present invention, it is possible to obtain a side-by-side anti-pill water-sensitive acrylic composite fiber excellent in post-processability and expected to be used in a wide range of products.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail. The acrylic composite fiber of the present invention has a high shrinkage component and a low shrinkage component. Both are acrylonitrile copolymers, and the raw material monomers include acrylonitrile as the first component, neutral monomer as the second component, and hydrophilic monomer as the third component.

[0010] The content of acrylonitrile (first component) is preferably 85% by weight or more in both the high shrinkage component and the low shrinkage component. If the content of acrylonitrile is lower than 85% by weight, the physical properties of the fibers are lowered, and the form stability of products such as clothing is undesirably deteriorated.

In general, the crimping of the side-by-side type composite fiber is caused by a difference in shrinkage based on a difference in copolymerization ratio of a copolymer component. From this viewpoint, in the present invention, as the neutral monomer of the second component, (meth) acrylates such as methyl acrylate and methyl methacrylate, which are copolymerizable with acrylonitrile, vinyl acetate, styrene, acrylamide, etc. Is copolymerized. The copolymerization ratio of the second component is 2 to 6 with respect to the high shrinkage component side.
%, Preferably 3 to 5% by weight of the high shrinkage component, and 4 to 9% by weight based on the low shrinkage component side.

The expression of water sensitivity of the side-by-side type conjugate fiber is due to a difference in swelling based on a difference in the copolymerization ratio of the hydrophilic copolymer component. From this viewpoint, in the present invention, (meth) acrylic acid, (meth)
A hydrophilic monomer such as allylsulfonic acid or styrenesulfonic acid and salts thereof is copolymerized. The copolymerization ratio of these third components is 3 to 5% by weight on the high shrinkage component side and 0 to 1% by weight on the low shrinkage component side.

The hydrophilic comonomer content of the high shrinkage component,
The difference between the low shrinkage component and the hydrophilic comonomer content is preferably 3% by weight or more, more preferably 3 to 5% by weight. By doing so, a swelling difference between the two components occurs, and good water sensitivity can be realized.

Next, the relationship between the properties of the fiber and the bulkiness, anti-pill property, and post-processability will be described. Comparing the performance of the fibers in which DS and DKS × DKE were changed by changing the manufacturing conditions variously, the following results were obtained (Table 1).

The post-processability of spinning and the like is governed by DS and DKS × DKE. When DS is less than 1.8 g / denier or DKS × DKF is less than 20, good post-processability cannot be obtained.

On the other hand, the anti-pill property mainly depends on DKS × DK
It was controlled by E, and the lower the value, the better. If this value exceeds 35, good anti-pill properties could not be obtained. Also, when DS is greater than 2.6 grams / denier,
Sufficient anti-pill properties could not be obtained.

From these experimental facts, to achieve both the above-mentioned post-processability and anti-pill property at a satisfactory level, DKS × D
KE is set to 20 to 35 and DS is set to 1.8 to 2.6 g /
Denier is preferred.

However, in the case of ordinary acrylic composite fibers, it is necessary to set the DS to 1.8 to 2.6 g / denier and to impart a sufficient crimping force to impart appropriate bulkiness after boiling water treatment. DKS x DKE is 60-8
It becomes 0. Therefore, good anti-pill properties cannot be obtained. It should be noted that DKS × DKE can be in the range of 20 to 35 by lowering the saturated steam pressure during the relaxation heat treatment, but when such treatment is performed, the crimp developing power is insufficient.

On the other hand, the acrylic conjugate fiber of the present invention is characterized by the composition of the high shrinkage component and the low shrinkage component and is excellent in crimping property.
S × DKE can be in the range of 20-35. For this reason, even if a pill occurs, it can easily fall off,
It shows very good anti-pill properties. Therefore, an acrylic composite fiber having good bulky properties, anti-pill properties, and good post-processing properties can be realized.

Further, the acrylic composite fiber of the present invention has a tensile strength DS of 1.8 to 2.6 g / denier and has a sufficiently high elongation. Less inconvenience such as generation and excellent in post-processability.

Next, a method for producing the high shrinkage component and the low shrinkage component will be described. These production methods are not particularly limited, and any of ordinary suspension polymerization, solution polymerization, emulsion polymerization and the like can be used. The polymerization degree of the polymer is determined by its specific viscosity (0.5 g of the polymer is dissolved in dimethylformamide 1).
Dissolved in 00 ml and measured at 30 ° C. ) Is 0.12-
It is preferably in the range of 0.21.

The stock solution for spinning a polymer comprises the high shrinkage component (A)
And the low-shrinkage component (B) are each dissolved in a common acrylonitrile polymer solvent, preferably an organic solvent such as dimethylacetamide, dimethylformamide, dimethylsulfoxide, etc., and have a viscosity of 5 when measured at 50 ° C.
It is preferably in the range of 0 to 100 poise,
More preferably, it is 100 poise. In the case of less than 50 poise, DKS × DKE is less than 20, and the pilling property is good, but problems such as generation of fly and decrease in yarn strength during post-processing such as spinning occur. On the other hand, if it exceeds 100 poise, DK may be obtained no matter what stretching ratio or relaxation condition is used.
It is difficult to reduce S × DKE to 35 or less, and sufficient anti-pill property cannot be obtained.

For the side-by-side wet composite spinning, a known method can be used, and the spinning solution (A),
(B) is discharged and coagulated into a solvent-water wet spinning bath into a side-by-side type using a conventional composite spinning circular die,
Then, it is stretched in hot water in a range of 3.0 to 5.0 times. If the draw ratio is high, DS and DKS × DKE tend to be high. If the draw ratio exceeds 5.0, the water-sensitive acrylic composite fiber with good anti-pill properties aimed at by the present invention cannot be obtained. On the other hand, when the draw ratio is reduced, the anti-pill property is improved, but is 3.0.
If the ratio is less than twice, naturally the DS becomes low and post-processing such as spinning becomes difficult, and at the same time, the crimp developing power peculiar to the conjugate fiber is lowered and the bulkiness is insufficient.

The undrawn yarn is washed in hot water simultaneously with the above-mentioned drawing treatment. The amount of residual solvent after washing is usually 0.5% or less. The washed and stretched fiber bundle is then subjected to a drying treatment.
The method of drying is not particularly limited, but a method of drying the fiber bundle after washing and drawing on a heating roll at 110 to 150 ° C under tension is preferable.

The dried fiber bundle is subjected to relaxation treatment in saturated steam having a saturated steam pressure Y of 1.3 to 2.0 kg / cm ² · G. This relaxation gives the fibers a shrinkage of 15-30%, preferably 20-25%. Here, the saturated steam pressure Y is determined by the draw ratio X and 4.5 <
It is preferable to satisfy the relationship of X + Y <6.5. As a result, it becomes possible to develop a three-dimensional crimped form unique to the side-by-side type conjugate fiber and to improve post-processability such as spinning.

[0026]

The contents of the present invention will be described below with reference to examples. In addition, the measurement of anti-pill property was performed according to JIS 1-1076 (193).
Method A (60 rpm) using an ICI tester specified in 7)
m, after 5 hours), and changes according to the appearance change of the knitted fabric.
Classified into Class 5 (hereinafter referred to as ICI anti-pill test).

The raw cotton having good anti-pill property means a cotton having a grade of 4 or higher in the ICI anti-pill test.

The knitted fabric sample used in the test was a worsted spinning of raw cotton to form a No. 36 double yarn, which was weighed by a knitting machine at about 200 g / m2.
The knitted fabric of No. ² was used.

For evaluation of water sensitivity, a sub-tow of about 300 d was prepared, a load of 2 mg was applied, treated in hot water of 90 ° C. or higher for 1 hour, and the length was measured (L _w ). Followed by measuring the air dried length at room temperature overnight (L _D). These wet and dry treatments are repeated three times, and calculated from the average of L _w and L _{D by} the following equation (2). Water sensitivity _{(%) = (L w -L} D) ÷ L W × 100 (2) The water-sensitive, it is preferably in the range of 10-20%.

Example 1 First, the following copolymers (a) and (b) were dissolved in dimethylacetamide (DMAc) by a conventional method so as to have respective predetermined concentrations, followed by filtration and defoaming. To obtain a spinning dope.

(A) AN-MA-MS Copolymer Methyl acrylate (MA) as a second component and sodium methallylsulfonate (MS) as a third component, having a composition of AN
/MA/MS=93.65/5.85/0.5 (% by weight) is an AN-MA-MS copolymer (hereinafter referred to as “AN”).
-MA-MS copolymer ". ). The specific viscosity (0.5 g of the polymer dissolved in 100 ml of dimethylformamide and measured at 30 ° C.) is 0.19.

(B) AN-MA-NaSS copolymer Methyl acrylate (MA) as the second component and sodium styrene sulfonate (hereinafter referred to as "NaSS") as the third component, having a composition of AN / MA / NaSS = 92. .5 /
3.5 / 4.0 (wt%) AN-MA-NaSS copolymer (hereinafter referred to as "AN-MA-NaSS copolymer"). The specific viscosity is 0.18.

The spinning dope has a viscosity at 50 ° C. of 20.
Adjusted within the range of ~ 450 poise.
~ 17 samples. At this time, the solid content concentration in the stock solution was 15 to 24% by weight.

Each of these spinning dopes has a pore size of 0.075 mm.
AN-MA-MS copolymer and AN-M through a side-by-side composite spinning nozzle with φ, 10,000 holes
The A-NaSS copolymer is extruded into a coagulation bath of 30% DMAc and 70% water at 40 ° C. so as to become a side-by-side type, and then stretched and washed with hot water 4.5 times, and a spinning oil is applied. After that, it was dried under tension with a 140 ° C. hot roller. 1.65 kg / cm ² ·
G in saturated steam for 25 minutes, 3 denier /
A fiber bundle having a filament fineness was obtained. afterwards,
After applying 1.1 times steam stretching to remove micro-crimps that cause fly generation in the spinning card process, crimping was performed again to an extent necessary for the spinning process. The DS and DKS × DKE of this fiber were measured, and the fiber was
It was bias cut to 6 to 127 mm to give a spun yarn of 2 / 36th. The spinnability was determined based on the amount of cotton dropped in the carding process. Those with a cotton loss of 0.01% or less were judged as good, and those with less than 0.01% were judged as poor. The spun yarn is further treated with 10% using 2% owf of the dye Katilon Blue CDRLH (manufactured by Hodogaya Chemical).
The mixture was stained with boiling water at 0 ° C. for 60 minutes. The dyed yarn was made into a knitted fabric, and the anti-pill performance was examined by the above-mentioned ICI anti-pill test.

DS, DK of fibers obtained in a series of tests
Table 1 shows the relationship between S × DKE, spinnability, and ICI pit test.
Are shown together.

[0036]

[Table 1] According to this, a fiber that simultaneously satisfies a DS of 1.8 to 2.6 (grams / denier) and a DKS × DKE of 20 to 35 (grams / denier ×%) has good spinnability and good anti-pill properties. Has become.

In the case of Nos. 1, 2, 3, and 7 in which DS was less than 1.8 g / denier or DKS × DKE was less than 20, spinning properties were all poor. DS is 2.6
No. 14, 15, 16, 17 exceeding gram / denier
Although the spinning property was good, the desired anti-pill property could not be obtained. Further, even if DS is in the range of 1.8 to 2.6 g / denier, if DKS × DKE exceeds 35, N
o5, 10, 12, and 13 had poor anti-pill properties and DK
When S × DKE was less than 20, No. 7 was poor in spinnability.

Further, it was confirmed that these properties were greatly affected by the viscosity of the stock solution from the viewpoint of production conditions, and it was found that the viscosity of the stock solution was preferably set to 50 to 100 poise.

Example 2 Two kinds of copolymers as in Example 1 (a) AN-MA-MS copolymer and (b)
The AN-MA-NaSS copolymer was dissolved in DMAc so that the viscosity at 50 ° C. became 80 poise to obtain a spin dope. Next, using the same method as in Example 1, spinning was performed using the stretching range and saturated steam as shown in Table 2 to obtain a fiber bundle having a fineness of 3 denier / filament. This fiber was post-treated in the same manner as in Example 1,
The spinnability, bulkiness and degree by the ICI pit test and sensory test were evaluated. Table 2 shows the results.

[0040]

[Table 2] According to this, the draw ratio X is 3.0 to 5.0 times, the saturated steam treatment pressure Y is 1.3 to 2.0 kg / cm ² · G, and X + Y is 4.5 to 6.5. No. 6, 7, 10,
11, 12, and 15 showed good evaluation results. In Nos. 1, 2, and 3 in which the draw ratio was less than 3.0 times, the anti-pill property was good, but the spinning was poor, and the bulkiness was insufficient. Further, even when the stretching ratio is in the range of 3 to 5 times, the saturated steam treatment pressure is less than 1.30 kg / cm ² · G.
In 4, 9, and 14, spinnability was poor, and bulkiness was also insufficient. N exceeding 2.00 kg / cm ² · G
In o8, 13, and 18, the anti-pill property was insufficient. Further, in No. 5, where X + Y is 4.5 or less even when the stretching ratio X is in the range of 3 to 5 times and the saturated steaming pressure Y is in the range of 1.3 to 2.0 kg / cm ² · G. However, the spinnability was poor and the bulkiness was insufficient. Further, in Nos. 16 and 17 where X + Y was 6.5 or more, the anti-pill property was insufficient. Also,
In Nos. 19, 20, and 21 in which the draw ratio exceeded 5.0 times, spinning properties and bulky properties were good, but anti-pill properties were insufficient.

Example 3 Fibers were prepared from the following copolymers in combinations shown in Table 3 and evaluated. (A) AN-MA-MS copolymer, (b) AN-MA
-NaSS copolymer, (c) AN-VAc-MS copolymer having vinyl acetate (VAc) as a second component, and MS as a third component, (d) AN-VAc copolymer 0.1
9, (b) was 0.18, (c) was 0.19, and (d) was 0.19. 50 of these copolymers
DMAc so that the stock solution viscosity at 80 ° C. becomes 80 poise
And spun in the same manner as in Example 1. At this time, the stretching ratio was 4.0 times and 1.65 kg / cm ² ···
A fiber bundle having a denier of 3 denier / filament was obtained by treatment with saturated steam of G.

These fibers were post-treated in the same manner as in Example 1 to give the fibers water sensitivity and spinnability, ICI anti-pill test,
The bulkiness and texture were evaluated by a sensory test. Table 3 shows the results.

[0043]

[Table 3] According to this, to obtain soft raw cotton which simultaneously satisfies anti-pill property and water sensitivity and has excellent post-processability, No.
It turns out that it is good to manufacture using the raw materials of Nos. 1-4.

[0044]

According to the present invention, it has the advantages of side-by-side water-sensitive acrylic composite fibers, such as bulky properties, soft texture and shape recovery properties, and is excellent in anti-pill properties. In addition, a fiber having a high commercial value and good post-processing properties such as spinning can be obtained.

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Hiroaki Onishi 20-1 Miyukicho, Otake City, Hiroshima Prefecture Inside Mitsubishi Rayon Co., Ltd. Otake Works (72) Inventor Kiyozo Oishi 201-1 Miyukicho, Otake City, Hiroshima Prefecture Mitsubishi Rayon Co., Ltd. Otake Works (72) Inventor Hidetaka Furukawa 20-1 Miyukicho, Otake City, Hiroshima Prefecture Mitsubishi Rayon Co., Ltd. Otake Works

Claims (5)

[Claims] 1. A side-by-side type anti-pill acrylic composite fiber comprising (a) 2 to 6% by weight of methyl acrylate or vinyl acetate and 3 to 3% of a hydrophilic comonomer.
A high-shrink component (A) comprising an acrylonitrile copolymer containing 5% by weight and (b) an acrylonitrile copolymer containing 4 to 9% by weight of methyl acrylate or vinyl acetate and 0 to 1% by weight of a hydrophilic comonomer. And a tensile strength of 1.8 to 2.6 (gram / denier), and a knot strength (gram / denier).
And an elongation of knot (%) of 20 to 35. 2. The method according to claim 1, wherein the difference between the hydrophilic comonomer content of the high shrinkage component (A) and the hydrophilic comonomer content of the low shrinkage component (B) is 3 to 5% by weight. The method for producing the acrylic composite fiber according to the above. 3. The spinning dope of the high shrinkage component (A) and the low shrinkage component (B) has a viscosity at 50 ° C. of 50 to 50.
A step of preparing the fiber so as to have a viscosity of 100 poise; a step of wet-composite spinning the spinning stock solution into a side-by-side type to form a fiber; Stretching at a draw ratio and drying, and relaxing the fiber in saturated steam having a saturated steam pressure of 1.3 to 2.0 kg / cm ² · G. 3. The method for producing an acrylic composite fiber according to 1 or 2. 4. The method for producing an acrylic composite fiber according to claim 3, wherein the fiber is contracted by 15 to 30% by the relaxation treatment in the saturated steam. 5. The method according to claim 3, wherein X and Y satisfy a relationship represented by the following formula (1), where X is the stretching magnification, and Y is the saturated water vapor pressure at the time of performing the relaxation treatment. Or the method for producing an acrylic composite fiber according to 4. 4.5 <X + Y <6.5 (1)