JPH09209264A - Fiber structure and production of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a fiber structure consisting of a polyester fiber and a cellulose fiber on which a polymerization process with a hydrophilic vinyl-based monomer is performed, and having excellent shrink proof and moisture absorbing properties. SOLUTION: This fiber structure material is obtained by impregnating an aqueous solution of pH6-12 containing 10-30wt.% concentration of a hydrophilic vinyl-based monomer such as 2-acrylamine-2-methylpropane sulfonic acid (salt) and 1-5wt.% polymerization initiator such as ammonium persulfate based on the monomer to a plain woven fabric consisting of a polyester/a cotton mixed spun yarn, heat-treating at 80-200 deg.C for polymerization processing at 1-20wt.% monomer reaction ratio, then washing and drying. The obtained fabric has a moisture absorbing property in which ΔMR of the difference of a moisture absorption MR2 (%) at temperature of 30 deg.C and at relative humidity of 90%, and the moisture absorption MR1(%) at 20 deg.C and at relative humidity of 65% satisfies the relationship of 0.04(100-x)<ΔMR<=0.14(100-x)[where (x) is a wt.% of the polyester fibers in the fiber structure].

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a fiber structure having excellent shrink resistance and hygroscopicity.

[0002]

2. Description of the Related Art Polyester fibers typified by polyethylene terephthalate fibers are excellent in heat resistance, strength characteristics, workability and shrink resistance, and are used in a wide variety of applications including clothing.

However, polyester fibers are considerably inferior to cellulose fibers such as cotton and hemp in hygroscopicity, which is one of the important properties relating to comfort when used for clothing. On the other hand, polyester fibers are superior to cellulose fibers in shrink resistance and strength.

Therefore, in order to make up for the defects of both the polyester fiber and the cellulose fiber, a method of blending or blending them has been conventionally adopted.

However, the fiber structure obtained by mixed spinning or mixed fiber has lower hygroscopicity than the fiber structure obtained from the cellulose fiber alone, and the shrinkage resistance is lower than that of the polyester fiber alone. It was something that was done.

[0006]

SUMMARY OF THE INVENTION The present invention provides a fiber structure composed of polyester fibers and cellulose fibers,
An object of the present invention is to provide a fiber structure having a higher hygroscopicity than that of a conventional fiber structure, and a method for producing the same, while substantially not impairing the shrink resistance of the polyester fiber.

[0007]

To achieve this object, the fiber structure of the present invention has the following constitution.

That is, a fiber structure comprising a polyester fiber and a cellulose fiber, wherein a hydrophilic vinyl monomer is polymerized in the cellulose fiber.

The method for producing a fiber structure according to the present invention has the following constitution.

That is, a fibrous structure comprising polyester fibers and cellulose fibers is impregnated with an aqueous solution containing a hydrophilic vinyl monomer and a polymerization initiator,
It is a method for producing a fiber structure, which comprises performing heat treatment and then washing.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below.

In the present invention, the polyester fiber includes
A fiber made of a polyester polymer having a fiber-forming property such as polyethylene terephthalate is used. The polyester polymer here includes not only a homopolymer but also a copolymer.

In the present invention, as the cellulose fiber, fibers having a skeleton of cellulose such as cotton, hemp and rayon are used.

The fiber structure of the present invention is a woven fabric, a knitted fabric, a non-woven fabric, or the like obtained by weaving or knitting a yarn in which polyester fibers and cellulose fibers are mixed-spun or mixed-fibered. Monomers are polymerized.

In the present invention, the hydrophilic vinyl-based monomer has a polymerizable vinyl group in its molecular structure, and has an acidic group such as carboxylic acid or sulfonic acid and / or its salt, hydroxyl group, amide group or the like. A monomer having a hydrophilic group.

Concretely, acrylic acid monomers such as acrylic acid, sodium acrylate, aluminum acrylate, zinc acrylate, calcium acrylate and magnesium acrylate, 2-acrylamido-2-methylpropanesulfonic acid, methacrylic acid. , Allyl alcohol, sodium allyl sulfonate, acrylamide, sodium vinyl sulfonate, sodium methallyl sulfonate, sodium styrene sulfonate and the like can be used. These may be used alone, or 2
More than one species may be used in combination.

Among these, 2-acrylamide-2
-A monomer containing sulfonic acid and / or its salt in the molecular structure of methyl propane sulfonic acid and / or its sodium salt, sodium allyl sulfonate, etc.,
It is preferable in terms of excellent reactivity.

The fibrous structure of the present invention is excellent in hygroscopicity because it comprises polyester fibers, but is composed of cellulose fibers polymerized with the above-mentioned hydrophilic vinyl monomers.

Here, "the hydrophilic vinyl-based monomer is polymerized on the cellulose fiber" means that the hydrophilic vinyl-based monomer is graft-polymerized on the cellulose fiber, and that the inside of the void (the hollow portion or the like) of the cellulose fiber is It means that the hydrophilic vinyl-based monomer is radically polymerized or that the hydrophilic vinyl-based monomer is radically polymerized inside the cellulose single fiber. The fact that the hydrophilic vinyl-based monomer is graft-polymerized or radical-polymerized in the voids of the cellulose fibers or inside the cellulose monofilaments makes the hygroscopic durability exceptional and does not hinder the texture of the woven or knitted fabric. preferable. The polymerization of the hydrophilic vinyl-based monomer can be confirmed by, for example, a section staining method. The section staining method is performed as follows. A paraffin-embedded fiber bundle is cut in the direction perpendicular to the fiber axis to prepare a section. This section is deembedded with an organic solvent or the like, then stained with an appropriate dye (for example, a basic dye), and washed with water. The presence of the hydrophilic vinyl polymer can be confirmed by observing this with an optical microscope.

The reaction rate of the hydrophilic vinyl-based monomer with respect to the fiber structure is preferably 1% by weight or more and 20% by weight or less from the viewpoint of obtaining excellent hygroscopicity while maintaining good texture of the fiber structure. . It is more preferably 3% by weight or more and 17% by weight or less, and further preferably 5% by weight or more and 15% by weight or less. The reaction rate as used herein means the proportion (% by weight) of the weight of the fiber structure increased by the polymerization of the hydrophilic vinyl-based monomer.
0 × [(absolute dry weight of fiber structure after polymerization of hydrophilic vinyl monomer)-(absolute dry weight of fiber structure before polymerization of hydrophilic vinyl monomer)] / (hydrophilic vinyl It is calculated from the absolute dry weight of the fiber structure before the polymerization of the system monomer).

The fiber structure of the present invention has a temperature of 30.
Moisture absorption rate MR2 of fiber structure at ℃ and humidity of 90%
ΔMR represented by the value obtained by subtracting the moisture absorption rate MR1 (%) of the fiber structure at a temperature of 20 ° C. and a humidity of 65% from (%)
However, it is preferable that the following formula is satisfied. 0.04x
(100-x) <ΔMR ≦ 0.14 × (100-x) Here, x represents the proportion (% by weight) of the polyester fiber in the fiber structure.

The moisture absorption rate MR1 (%) of the fiber structure at a temperature of 20 ° C. and a humidity of 65% can be considered to be the hygroscopicity of clothes in a standard environment. Moisture absorption rate MR of fiber structure at 90% humidity
2 (%) can be considered to be the hygroscopicity of clothes after light exercise.

The ΔMR of the fiber structure which is substantially composed of the cellulose fibers in which the hydrophilic vinyl monomer is not polymerized is 3.6 to 4.

The fiber structure of the present invention has a shrinkage ratio of 3
% Or less is preferable. It is more preferable that the shrinkage rate is 2% or less.

The fibrous structure of the present invention exhibits high hygroscopicity because the hydrophilic vinyl-based monomer is graft-polymerized on the cellulose fiber, while the hydrophobic polyester fiber itself contains the hydrophilic vinyl-based monomer. Since it does not polymerize, it is possible to retain the shrink resistance, which is a characteristic feature of polyester fibers.

Next, the method for producing the fiber structure of the present invention will be described.

A fibrous structure obtained by weaving or knitting a woven fabric, a knitted fabric, a non-woven fabric or the like using a yarn obtained by blending or blending polyester fibers and cellulose fibers with a hydrophilic vinyl monomer and a polymerization initiator. The fiber structure of the present invention can be obtained by performing an impregnation treatment of an aqueous solution containing a, heat treatment, and then washing.

As a method for impregnating a fiber structure made of polyester fibers and cellulose fibers with an aqueous solution containing a hydrophilic vinyl monomer and a polymerization initiator, for example, a method of dipping for a certain period of time or a method of padding is used. Can be adopted. The impregnation temperature is not particularly limited and may be room temperature.

In the present invention, a polymerization initiator generally used in radical polymerization is preferably used as the polymerization initiator. Specifically, peroxides such as ammonium persulfate and benzoyl peroxide, azo catalysts and cerium catalysts are preferably used.

The concentration of the hydrophilic vinyl-based monomer in the aqueous solution containing the hydrophilic vinyl-based monomer and the polymerization initiator is
Although not particularly limited, a concentration of 10% by weight or more and 30% by weight or less is preferable from the viewpoint of efficiently carrying out the reaction. 13% by weight
It is more preferably at least 27% by weight, and even more preferably at least 15% by weight and at most 25% by weight.

The concentration of the polymerization initiator in the aqueous solution containing the hydrophilic vinyl monomer and the polymerization initiator is not particularly limited, but from the viewpoint of efficiently carrying out the reaction, the concentration is 1 relative to the hydrophilic vinyl monomer. The content is preferably 5% by weight or more and 5% by weight or less, more preferably 2% by weight or more and 4% by weight or less.

From the viewpoint of suppressing the deterioration of strength and physical properties of a fiber structure using polyester fibers and cellulose fibers, and efficiently carrying out the reaction, the pH of an aqueous solution containing a hydrophilic vinyl monomer and a polymerization initiator. Is preferably 6 or more and 12 or less, and more preferably pH 7 or more and 11 or less.

In the method for producing a fiber structure of the present invention, a heat treatment is carried out after the impregnation treatment, and the heat treatment is essential for carrying out the polymerization reaction. The heat treatment may be dry heat treatment, wet heat treatment or the like without particular limitation. The heat treatment temperature for carrying out this polymerization is not particularly limited, but it is preferably carried out at a temperature of 80 ° C. or higher and 200 ° C. or lower from the viewpoint of efficiently carrying out the polymerization reaction. Heat treatment is performed in one step or in two or more steps. The heat treatment time is determined in consideration of the heat treatment temperature in consideration of the target reaction rate, but is preferably 20 seconds or more and 5 minutes or less.

Further, after the heat treatment, it is necessary to wash the fiber structure to remove unreacted monomers and the like. The washing method is not particularly limited and may be washing with water or washing with hot water, but washing with hot water can be preferably used from the viewpoint of washing efficiency.

The fiber structure thus obtained has a higher hygroscopicity than the conventional fiber structure using the polyester fiber and the cellulose fiber, while hardly impairing the high shrinkage resistance of the polyester fiber.

[0036]

EXAMPLES The present invention will be described more specifically below with reference to examples. Each characteristic value in the examples was determined by the following method.

(1) Hygroscopicity The hygroscopicity was determined by allowing the fiber structure to stand in a thermo-hygrostat for 24 hours in an atmosphere of absolutely dry weight and a temperature of 20 ° C. and a humidity of 65% or a temperature of 30 ° C. and a humidity of 90%. From the weight change with the weight of the subsequent fiber structure, it was determined by the following formula.

Moisture absorption rate (%) = 100 × [(weight of fiber structure after standing at constant temperature and humidity)-(absolute dry weight of fiber structure)] / (absolute dry weight of fiber structure) From the moisture absorption rate MR1 under the conditions of temperature 20 ° C. and humidity 65% and the moisture absorption rate MR2 under the conditions of temperature 30 ° C. and humidity 90%, ΔMR was calculated by the following equation.

ΔMR = MR2-MR1 (2) Reaction rate The reaction rate is the absolute dry weight of the fiber structure before the polymerization of the hydrophilic vinyl monomer and the absolute dry weight of the fiber structure after the polymerization. Was calculated from the following formula.

Reaction rate (%) = 100 × [(absolute dry weight of fiber structure after polymerization of hydrophilic vinyl monomer)-
(Absolute dry weight of fiber structure before polymerization of hydrophilic vinyl monomer)] / (Absolute dry weight of fiber structure before polymerization of hydrophilic vinyl monomer) (3) Shrinkage rate JIS L 1042 It was determined by measuring the shrinkage rate (%) after washing as described.

Example 1 Short polyester fibers (single fiber fineness 0.17 tex, cut length 40 mm) and cotton were mixed and spun by a conventional method (mixing ratio:
50% by weight of polyester and 50% by weight of cotton), and a spun yarn of 45 count were obtained. Then, using this spun yarn as warp and weft, a plain woven fabric (warp density 115 yarns / inch, weft density 76 yarns / inch)
inch) was woven.

10 g of this woven fabric was impregnated with 100 g of an aqueous solution containing 20 g of 2-acrylamido-2-methylpropanesulfonic acid and 0.6 g of ammonium persulfate (adjusted to pH 8) and then heat-treated at 160 ° C. for 3 minutes. went. After the heat treatment, it was washed with hot water at 60 ° C.

After drying, the resulting fabric had a reaction rate of 2-acrylamido-2-methylpropanesulfonic acid of 8%,
The ΔMR was 5% and the shrinkage rate was 2%. This woven fabric had an excellent hygroscopic property equivalent to or exceeding 100% of cotton, and also had excellent shrink resistance.

Example 2 Polyester short fibers (single fiber fineness 0.17 tex, cut length 40 mm) and cotton were mixed and spun by a conventional method (mixing ratio:
Polyester 65% by weight, cotton 35% by weight), and a spun yarn of 45 count were obtained. Then, this spun yarn was woven into a half tricot with 36 gauge.

10 g of this knitted fabric was impregnated with 100 g of an aqueous solution containing 20 g of sodium acrylate and 0.4 g of ammonium persulfate (adjusted to pH 7), and then 18
Heat treatment was performed at 0 ° C. for 20 seconds. After the heat treatment, washing was performed with hot water at 80 ° C. The obtained knitted fabric had a sodium acrylate reaction rate of 4%, a ΔMR of 3%, and a shrinkage rate of 2%. This knitted fabric had an excellent hygroscopic property and an excellent shrink-proof property.

Examples 3 to 5 Example 1 was repeated except that the mixing ratio of polyester fiber was changed. The results are shown in Table 1. All had excellent hygroscopicity and shrink resistance.

[0047]

[Table 1] Examples 6 to 9 The same procedure as in Example 1 was carried out except that the kind of hydrophilic vinyl-based monomer was changed. Table 2 shows the results. All had excellent hygroscopicity and shrink resistance.

[0048]

[Table 2] Examples 10 to 13 The same procedure as in Example 1 was carried out except that the pH of the aqueous solution containing the hydrophilic vinyl monomer and the polymerization initiator was changed. The results are shown in Table 3. All had excellent hygroscopicity and shrink resistance.

[0049]

[Table 3] Examples 14 to 17 The procedure of Example 1 was repeated, except that the concentration of the hydrophilic vinyl-based monomer in the aqueous solution was changed. The results are shown in Table 4.
All had excellent hygroscopicity and shrink resistance.

[0050]

[Table 4] Examples 18 to 21 The same procedure as in Example 1 was carried out except that the concentration of the polymerization initiator was changed with respect to the hydrophilic vinyl monomer. Table 5 shows the results
Shown in All had excellent hygroscopicity and shrink resistance.

[0051]

[Table 5] Examples 22 to 25 The same procedure as in Example 1 was performed except that the heat treatment temperature was changed. Table 6 shows the results. All had excellent hygroscopicity and shrink resistance.

[0052]

[Table 6] Comparative Example 1 The procedure of Example 1 was repeated except that methyl methacrylate was used instead of 2-acrylamido-2-methylpropanesulfonic acid. The obtained woven fabric has a reaction rate of 6%, Δ
The MR was 1.5% and the shrinkage was 2.5%. This fabric had poor hygroscopicity.

Comparative Example 2 Example 1 except that 2-acrylamido-2-methylpropanesulfonic acid and ammonium persulfate were not used.
I went the same way. The obtained woven fabric had a ΔMR of 2% and a shrinkage rate of 3%. This fabric had poor hygroscopicity.

Comparative Example 3 Example 1 was repeated except that a plain woven fabric was formed by using spun yarn of 45% count made of 100% cotton. The resulting fabric has a ΔMR
Was 14% and the shrinkage rate was 5.5%. This woven fabric was inferior in shrink resistance.

Comparative Example 4 The same procedure as in Example 1 was carried out except that a plain weave fabric was formed by using a 45-count spun yarn of 100% polyester fiber. The resulting woven fabric had a shrinkage of 0.5% and a ΔMR of 0%. This fabric had very poor hygroscopicity.

[0056]

EFFECTS OF THE INVENTION According to the present invention, since it has excellent hygroscopicity, it has excellent comfort when worn, and it also has excellent shrink resistance, so that it is possible to provide a fibrous structure which can be widely used for clothing.

Claims (10)

[Claims] 1. A fiber structure comprising a polyester fiber and a cellulose fiber, wherein the cellulose fiber is polymerized with a hydrophilic vinyl monomer. 2. A value obtained by subtracting the moisture absorption rate MR1 (%) of the fiber structure at a temperature of 20 ° C. and a humidity of 65% from the moisture absorption rate MR2 (%) of the fiber structure at a temperature of 30 ° C. and a humidity of 90%. The fibrous structure according to claim 1, wherein ΔMR satisfies the following formula. 0.04 × (100−x) <ΔMR ≦ 0.14 × (10
0-x) Here, x represents the ratio (% by weight) of the polyester fiber in the fiber structure. 3. The fiber structure according to claim 1, wherein the reaction rate of the hydrophilic vinyl-based monomer with respect to the fiber structure is 1% by weight or more and 20% by weight or less. 4. The fiber structure according to claim 1, wherein the hydrophilic vinyl-based monomer is a vinyl-based monomer containing sulfonic acid and / or sulfonate. 5. A fibrous structure comprising polyester fibers and cellulose fibers is impregnated with an aqueous solution containing a hydrophilic vinyl monomer and a polymerization initiator, followed by heat treatment and then washing. And a method for manufacturing a fiber structure. 6. The method for producing a fiber structure according to claim 5, wherein the hydrophilic vinyl-based monomer is a vinyl-based monomer containing sulfonic acid and / or sulfonate. 7. The method for producing a fiber structure according to claim 5, wherein the pH of the aqueous solution is 6 or more and 12 or less. 8. The method for producing a fiber structure according to claim 5, wherein the concentration of the hydrophilic vinyl-based monomer in the aqueous solution is 10% by weight or more and 30% by weight or less. 9. The method for producing a fiber structure according to claim 5, wherein the polymerization initiator is contained in an amount of 1% by weight or more and 5% by weight or less with respect to the hydrophilic vinyl-based monomer. 10. The method for producing a fiber structure according to claim 5, wherein the heat treatment temperature is 80 ° C. or higher and 200 ° C. or lower.