JP3073154B2 - Method for producing modified cellulose acetate fiber - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a modified cellulose acetate fiber. More specifically, a refreshing feeling with a large number of fine crater-shaped recesses on the surface,
The present invention relates to a method for producing a modified cellulose acetate fiber having excellent deep colorability.

[0002]

2. Description of the Related Art In the field of garment textiles, various modifications of various natural fibers and chemical fibers have been made due to diversification and upgrading of consumer needs. For example, in the case of polyester fibers, in order to obtain a dry feeling and deep color, there is a technique of forming fine crater-like irregularities on the fiber surface by reducing the weight of a raw yarn kneaded with silica fine particles by alkali treatment. Are known. In this technique, the fibers around the silica-based fine particles are easily decomposed specifically by alkali, and the fine particles fall off to form fine crater-like irregularities on the fiber surface (Japanese Patent Publication No. 9205/1992). etc).

[0003] Various methods for changing the fiber surface of cellulose acetate fibers have also been proposed. For example, when spinning cellulose acetate fiber, dry spinning is performed in a steam atmosphere to form voids on the fiber surface (Japanese Patent Laid-Open No. 54-6918). A method of forming only irregularities by dissolving only the very surface layer by immersion treatment (Japanese Patent Laid-Open No. 55-93)
814) has been reported, but the obtained fiber has a markedly reduced strength and elongation and large unevenness in treatment and the like, and has a practically difficult surface.

In addition, a method for controlling the fiber forming process at the time of spinning, specifically, setting the discharge linear speed and winding speed of the spinning stock solution at the spinning nozzle to appropriate conditions, and imparting complicated irregularities to the fiber surface. Method (Japanese Patent Publication No. 3-36928)
The cellulose acetate fiber obtained by the method has large irregularities, and it is difficult to obtain fine crater-like irregularities on the fiber surface by such a method.

[0005] Furthermore, a method of subjecting cellulose acetate fiber to biochemical treatment to form irregularities on the fiber surface, more specifically, a method of treating cellulose acetate fiber with alkali to convert the fiber surface layer to cellulose, and then using a cellulose-degrading enzyme. A method for decomposing and removing a cellulosic portion (JP-A-5-2706)
No. 7) and a method of subjecting cellulose acetate fiber to alkali treatment to convert the fiber surface to cellulose, and then decomposing and removing the cellulized portion with a disinfectant (JP-A-6-264364). However, fine irregularities similar to those in the polyester fiber have not been formed yet.

Also, irregularities are formed on the surface by a method in which fine particles of an inorganic material having an average particle size of 0.01 to 0.3 μm are mixed in advance with a cellulose acetate fiber in a spinning solution (Japanese Patent Application Laid-Open No. 7-97713). Although a method is known, in such a method of simply dispersing the fine particle inorganic substance throughout the fiber, in order to form a sufficient unevenness on the surface,
It is necessary to incorporate a very large amount of fine particle inorganic material inside the fiber, and as a result, the fiber strength which is originally lower than that of other fibers is further reduced, and the glossiness unique to cellulose acetate fiber is significantly reduced. In addition, the formed irregularities are projected in a convex shape with respect to the fiber surface.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to form a large number of fine crater-like irregularities on the surface of a cellulose acetate fiber to provide an unprecedented cooling sensation and a deep color, and It is an object of the present invention to provide a method for producing a modified cellulose acetate fiber having a practical and practical fiber strength.

[0008]

The gist of the present invention is that cellulose acetate fibers kneaded with inorganic fine particles alone or composite yarns composed of cellulose acetate fibers kneaded with inorganic fine particles and other fibers are mixed with an alkali compound. By alkali treatment, at least the surface of the cellulose acetate fiber is converted to cellulose, and then treated with a disinfectant to decompose and remove at least a part of the cellulose converted portion, thereby forming a fine crater-shaped concave portion on the surface of the cellulose acetate fiber. A method for producing a modified cellulose acetate fiber, characterized in that it is formed.

The cellulose acetate fiber used in the present invention may be cellulose triacetate having an acetylation degree of 56.2% to 62.5% or cellulose diacetate having an acetylation degree of 48.8% to 56.2%. The shape may be any of filament and staple.

In the cellulose acetate fiber used in the present invention, it is necessary that the fine particle inorganic substance is kneaded and contained in a so-called fiber which is obtained by adding a fine particle inorganic substance to a spinning solution. Examples of such a fine particle inorganic substance include calcium carbonate, silicon dioxide, and titanium oxide. Furthermore, this fine particle inorganic substance is more than cellulose acetate,
If high specific gravity, preferably, the specific gravity of the fine particle inorganic material,
If it is 3.5 or more, improvement in drape property can be expected.
In addition, by using an inorganic substance having a refractive index of 1.3 to 1.9, preferably 1.4 to 1.7 as the fine particle inorganic substance, it is possible to suppress a decrease in glossiness. That is, since the inorganic substance having such a refractive index is close to the refractive index of cellulose acetate, it is possible to suppress a decrease in glossiness, and the refractive index is 1.3 to 1.
When the ratio is outside the range of 9, the glossiness and the good coloring property, which are the characteristics of the cellulose acetate fiber, may be impaired. As an inorganic material satisfying such specific gravity and refractive index, specifically,
For example, barium carbonate (refractive index 1.53, specific gravity 4.
4), barium sulfate (refractive index 1.64, specific gravity 4.1),
Zinc oxide (refractive index 1.9, specific gravity 5.6) and the like. In particular, barium sulfate is very preferable in terms of increasing the specific gravity and glossiness, and further affecting the human body (chemical and physical stability).

Also, the physical properties of the fibers differ depending on the size of the aggregates (aggregates) of the fine particles of inorganic material contained in the cellulose acetate fiber component, which affects the spinnability and the post-process passability. It is preferable that the average particle diameter of the aggregate of the inorganic fine particles to be made is 1.5 μm or less, more preferably, the average particle diameter of the aggregate is 1 μm.
It is as follows. If it is larger than this, the fiber properties are significantly reduced, and the spinnability, the post-process passability, etc. are extremely deteriorated. In order to reduce the average particle size of the aggregate to 1.5 μm or less, the primary particle size (average particle size) of the added inorganic fine particles should be 0.5 μm.
m, more preferably 0.05 or less.
μm. If it is larger than this, the average particle diameter of the aggregates of the inorganic fine particles becomes large, and the physical properties of the fiber are liable to be extremely deteriorated. Further, troubles such as thread breakage in the fiber formation, for example, in a spinning step, occur frequently.

The content of the inorganic fine particles in the cellulose acetate fiber component is 5 to 30% by weight, preferably 5 to 20% by weight.
% By weight, and less than 5% by weight, the cellulose acetate fiber is alkali-treated with an alkali compound to convert at least the surface of the cellulose acetate fiber into cellulose,
Next, by treating with a disinfectant to decompose and remove at least a part of the cellulosic portion, it becomes difficult to form many fine crater-like concave portions on the fiber surface,
It is difficult to obtain a sufficient refreshing feeling and deep color. Also, 30
If the content is more than 10% by weight, the strength and elongation of the fiber may be significantly reduced, which may be a practical problem.

[0013] In the present invention, an alkali metal hydroxide such as sodium hydroxide, potassium hydroxide or the like may be used as an alkali compound to be used when the cellulose acetate fiber is alkali-treated with an alkali compound to convert at least the surface of the cellulose acetate fiber into cellulose. Cellulose acetate fiber kneaded with 1-30% by weight of inorganic fine particles using alkaline earth metal hydroxides such as calcium hydroxide and magnesium hydroxide, conjugate salts of strong alkalis and weak acids such as sodium hydrogen carbonate and sodium carbonate, etc. Is immersed in an aqueous solution of 0.5 to 40% by weight (based on cellulose acetate fiber) of an alkali compound at room temperature to 130 ° C. for 5 to 120 minutes to carry out alkali treatment. Alternatively, it is immersed in a 1 to 45% by weight aqueous solution of an alkali compound at room temperature and then subjected to squeezing with a nip roller such as a mangle, dry heat at room temperature to 180 ° C., or heat treatment such as steaming to carry out alkali treatment. By the alkali treatment, at least the cellulose acetate fiber in which the fiber surface has been converted to cellulose, is treated with a disinfectant to decompose and remove the cellulized layer and to remove the fine particle inorganic substance on the fiber surface layer. A crater-shaped recess is formed.

The desiccant used in the present invention is preferably an acid that carbonizes and hydrolyzes cellulose, inorganic acids such as sulfuric acid and hydrochloric acid, sodium hydrogen sulfate, aluminum sulfate, ferrous sulfate, ferric sulfate, and ammonium sulfate. Sulfates such as zinc sulfate, stannous sulfate, ferrous chloride, ferric chloride, aluminum chloride, magnesium chloride, zinc chloride, cobalt chloride, cuprous chloride, cupric chloride, nickel chloride, chloride 1
Chlorides such as tin and stannic chloride, chlorates such as sodium chlorate, aluminum chlorate, potassium chlorate and sodium chlorite; nitrates such as chromium nitrate, copper nitrate and zinc nitrate; ferrous oxalate; Oxalates such as ferric oxalate and stannous oxalate;
Examples thereof include acetates such as zinc acetate, phosphates such as zinc phosphate, and organic acids such as alkylnaphthalene sulfonic acid.

The disinfectant treatment depends on the kind of the disinfectant and the degree of modification of the cellulose acetate fiber, that is, the degree of texture required, but the alkali-treated cellulose acetate fiber is added in an amount of 0.5 to 20 wt. % Aqueous solution and squeezed with a nip roller such as a mangle, etc.
Dry heat or steaming heat at 0 ° C. is performed for 1 to 60 minutes. By the removal agent, by decomposing and removing at least a part of the cellulosic layer of the cellulose acetate fiber,
Fine crater-shaped concave portions can be formed on the fiber surface. In general, the acid of the disinfectant also erodes the cellulose acetate fiber, but since cellulose is extremely sensitive to the action of the acid, the surface of the cellulose acetate fiber easily formed by alkali treatment by controlling the concentration and temperature of the aqueous solution of the disinfectant. Only the cellulosic layer can be decomposed and removed.

In the modified cellulose acetate fiber of the present invention, the surface layer of the fiber may be cellulosic, that is, a base cellulose acetate fiber, the surface layer of which is a cellulosic layer, and the surface of which has a fine crater-like surface. Although it may be concave, the cellulosic layer is preferably a thin layer in order to maintain the basic performance of the cellulose acetate fiber. The presence of a cellulosic layer also allows dyeing with cellulosic fiber dyes, such as direct dyes. The thus obtained modified cellulose acetate fiber of the present invention has fine crater-like concave portions on the fiber surface and has a crater size of 3 μm.
m or less fine crater-shaped recesses are randomly present on the fiber surface, and give the cellulose acetate fiber a refreshing feeling and deep color, but from the viewpoint of further improving the refreshing feeling and deep color,
30 fine crater-shaped depressions per 1 × 10 ^-2 mm ²
It is preferable to have 0 or more. The modified cellulose acetate fiber of the present invention having fine crater-shaped concave portions on the fiber surface has a very refreshing feeling not found in conventional cellulose acetate fibers due to its surface structure, and has a deep feeling due to irregular reflection of light when dyed. It has color properties.

In the alkali treatment of the present invention, the selection, concentration, temperature, time and the like of the alkali compound are adjusted depending on the degree of modification of the modified cellulose acetate fiber.
In the disinfectant treatment, selection, concentration, temperature, time and the like of the disinfectant are adjusted depending on the amount of the cellulosic portion and the degree of removal of the cellulosic layer.

The cellulose acetate fiber into which the inorganic substance has been kneaded in the present invention can be composited with one or more other fibers to form a composite yarn. And natural fibers such as wool, and synthetic fibers such as nylon fibers, polyester fibers, acrylic fibers, and polyurethane fibers. The shape thereof may be any of filaments and staples. In addition, any known method such as air compounding, compound false twisting, and twisting can be applied to the compounding method.

In order to obtain the modified cellulose acetate fiber composite yarn of the present invention, it can be obtained basically in the same manner as in the case of the above-mentioned modified cellulose acetate fiber, Accordingly, the alkali treatment conditions and the disinfectant treatment conditions are appropriately changed within the above range.

The modified cellulose acetate fiber composite yarn of the present invention has a cooling sensation based on cellulose acetate fibers having fine crater-like concave portions and a deep color, and also has the performance of other fibers.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below.
To obtain the cellulose acetate fiber used in the present invention,
The following method is adopted. The flakes of cellulose triacetate or cellulose diacetate are dissolved in a single solvent such as methylene chloride or acetone or a mixed solvent such as methylene chloride and methanol to obtain a stock solution having a solution concentration of 15 to 30% by weight, preferably 18 to 27% by weight. Prepare.

In order to obtain a cellulose acetate fiber containing fine particles used in the present invention, a dispersion obtained by dispersing a fine particle inorganic material in a predetermined size of an aggregate in a solvent of cellulose acetate at the time of preparing a spinning dope is used. In a solution of cellulose acetate dissolved in an acetate solvent,
Addition, mixing, or directly adding the fine particle inorganic matter to a solution in which cellulose acetate is dissolved in a cellulose acetate soluble solvent, adding and mixing, and adjusting the size of the aggregate of the fine particle inorganic matter by predetermined dispersion conditions, etc. By the method, the inorganic fine particles are dispersed and contained in the spinning dope.

Here, it is important to prepare a spinning solution so that the average particle size of the aggregates does not increase. As a method for adjusting the average particle size of the aggregate, it is preferable to use a disperser. For example, when a horizontal sand mill is used as a dispersing machine, the disk peripheral speed and the bead diameter (0.8 to
1.0 mmφ), the bead filling ratio, the residence time in the vessel, and the like can be appropriately adjusted so that the average particle size of the aggregates does not increase.

The spinning solution containing inorganic particles thus obtained is supplied to a spinning nozzle device and spun by a dry spinning method in which the spinning solution is discharged into a high-temperature atmosphere. In addition, wet spinning may be performed instead of dry spinning.

The cellulose acetate fiber thus obtained is formed into a fabric. In the fiber state, that is, in a plastic bobbin wound state or a skein wound state, the alkali treatment with the following alkali compound and the disinfectant treatment may be performed. Generally, after forming a fabric, it is scoured and dried, and the scoured fabric is put into an aqueous solution of an alkali compound such as sodium hydroxide, and alkali-treated at a high temperature (100 ° C. or higher) to convert the fiber surface of the cellulose acetate fiber into cellulose. . Next, the cloth is immersed in an aqueous solution of a disinfectant such as sodium hydrogen sulfate, impregnated with a nip, steamed, washed and dried.

[0026]

The present invention will be described below in more detail with reference to examples. The evaluation in the examples was based on the following method.

(Crater formation state): Judgment from electron micrograph ◎: good ×: none

(Number of craters): Judgment from electron micrographs Pieces / 1 × 10 ^-2 mm ²

(Weight loss rate of the treatment with the disinfectant): [(weight of fabric before treatment with the disinfectant-weight of fabric after treatment with the disinfectant) /
Weight of the fabric before the treatment with the disinfectant] × 100 (%)

Example 1 Five-sheet satin woven fabric using Bright 80d / 20f made of cellulose triacetate fiber having a degree of acetylation of 61.3% kneaded with 18% by weight of barium sulfate for warp and similarly 100d / 26f Bright for weft. (200 density / inch, weft density 87 density / inch)
It was scoured and dried using a continuous tank scouring machine. This scoured fabric is put into an aqueous solution of 7% by weight of sodium hydroxide (to fabric) having a bath ratio of 1:20, and the temperature is raised from 30 ° C. at a rate of 2 ° C./min.
The fiber surface of the constituent fibers was converted to cellulose by alkali treatment for 0 minutes, and an alkali-treated fabric having an alkali weight loss of 7.2% was obtained. Next, this fabric is used with sodium hydrogen sulfate monohydrate (34-37% as sulfuric acid) as a disinfectant,
It was immersed in the 7% by weight aqueous solution, nipped and impregnated with 93% by weight of the solution, steamed at 130 ° C. for 10 minutes, washed with water, and dried. The obtained woven fabric was evaluated for the formation state and number of crater-like concave portions on the fiber surface of the constituent fibers, and the rate of weight loss of the disinfectant treatment, and the evaluation results are shown in Table 1.

(Comparative Example 1) In Example 1, the scoured fabric was treated in the same manner as in Example 1 without using an alkali treatment, and the fabric was treated in the same manner as in Example 1. The evaluation results are shown in Table 1. .

(Comparative Example 2) In Example 1, the fabric which had been subjected to alkali treatment but not treated with an antidote was evaluated in the same manner as in Example 1, and the evaluation results are shown in Table 1.

[0033]

[Table 1]

Example 2 Air entangled composite yarn of cellulose triacetate fiber Bright 80d / 20f and polyester fiber semi-dal 20d / 12f mixed with 181.3% by weight of barium sulfate and kneaded with 61.3% acetylation degree, used for warp and weft 5 satin woven fabrics (warp density 160 / inch, weft density 70
Book / inch) was scoured and dried in a 6-tank continuous scouring machine. This scoured fabric is put into an aqueous solution of 5.5% by weight of sodium hydroxide (to fabric) having a bath ratio of 1:20, and the temperature is raised from 30 ° C. at a rate of 2 ° C./minute, and alkali-treated at 120 ° C. for 60 minutes to obtain cellulose triacetate. The fiber surface of the fiber was converted to cellulose to obtain an alkali-treated fabric having an alkali weight loss rate of 5.7%. Next, the woven fabric was immersed in a 7% by weight aqueous solution of sodium hydrogen sulfate monohydrate (34 to 37% as sulfuric acid) as a disinfectant, nipped and impregnated with 95% by weight of liquid. And steamed at 130 ° C. for 10 minutes, washed with water and dried. The obtained woven fabric was evaluated for the formation state and number of crater-shaped concave portions on the fiber surface of the constituent fibers, and the rate of weight loss of the disinfectant treatment. The evaluation results are shown in Table 2.

(Comparative Example 3) In Example 2, the scoured fabric was treated in the same manner as in Example 2 without the alkali treatment, and the same fabric was treated in the same manner as in Example 2. The evaluation results are shown in Table 2. .

(Comparative Example 4) In Example 2, the fabric which had been subjected to the alkali treatment but without the treatment of the deodorant was evaluated in the same manner as in Example 2, and the evaluation results are shown in Table 2.

[0037]

[Table 2]

[0038]

According to the present invention, a modified cellulose having fine crater-shaped concave portions on the surface of cellulose acetate fiber is obtained by subjecting cellulose acetate fiber into which fine particles of inorganic material have been kneaded to an alkali treatment and then to a disinfectant treatment. Acetate fibers can be obtained with good controllability. This modified cellulose acetate fiber has a very cool feeling due to the fine crater-like concave portions, and has an improved deep color due to irregular reflection of light. In a similar manner, the composite yarn composed of cellulose acetate fiber kneaded with fine-particle inorganic material and other fibers has the same performance as the cellulose acetate fiber having fine crater-shaped recesses on the surface of the cellulose acetate fiber. The modified cellulose acetate fiber composite yarn can be obtained.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-7-26471 (JP, A) JP-A-7-97713 (JP, A) JP-A-5-311506 (JP, A) JP-A-6-271 264364 (JP, A) JP-A-7-138871 (JP, A) JP-A-64-61568 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) D06M 11/00-11 / 84

Claims (2)

(57) [Claims] At least the surface of cellulose acetate fiber obtained by alkali-treating a cellulose acetate fiber kneaded with a fine particle inorganic substance alone or a composite yarn comprising cellulose acetate fiber kneaded with a fine particle inorganic substance and another fiber with an alkali compound. Cellulose, and then treated with a disinfectant to decompose and remove at least a part of the cellulized portion, thereby forming fine crater-shaped concave portions on the surface of the cellulose acetate fiber. A method for producing acetate fibers. 2. The method for producing a modified cellulose acetate fiber according to claim 1, wherein the other fiber is a polyester fiber.