JPH0299609A - Production method for novel acrylic synthetic fiber - Google Patents

Abstract

PURPOSE:To obtain the title fiber having high moisture absorbability and linen- like touch with dry and crisp feel by wet-spinning the dope of a mixture of cellulose acetate and an acrylonitrile copolymer with a common solvent in a specific composition. CONSTITUTION:10 to 50wt.%, preferably 20 to 40wt.% of cellulose acetate and 90 to 50wt.%, preferably 80 to 60wt.% of an acrylonitrile copolymer (preferably of 30,000 to 80,000 molecular weight) are mixed with a common solvent, preferably DMF, dimethyl sulfoxide, or dimethylacetamide to prepare a spinning dope. Then, the dope is subjected to wet spinning to give the objective fibers.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for producing a novel acrylic synthetic fiber having a dry linen-like texture.

<Conventional technology> Conventional synthetic fibers have a unique luster and sliminess derived from the smoothness of their surfaces, and while they have many other characteristics, these two points in particular are the major differences between them and natural fibers. This is a difference, and various efforts are being made to improve this point.

For example, efforts are being made to make the cross section of the fibers irregular, such as triangular or hexagonal, to eliminate the luster characteristic of synthetic fibers and to create a silk-like luster. Furthermore, as shown in Japanese Patent Application Laid-Open No. 58-191216, a method has been devised in which fibers obtained from a mixture of a polyamide polymer and an acrylonitrile (IJv) polymer are bonded by dry heat treatment to create a V-shaped feel. However, at present, the results have not been sufficiently satisfactory.

<Problems to be Solved by the Invention> The present inventors have arrived at the present invention as a result of intensive research to eliminate the luster and sliminess characteristic of such synthetic fibers. The main purpose of the present invention is to eliminate the slimy texture characteristic of synthetic fibers and create a dry-touch texture, while at the same time diffusely reflecting light due to the deep wrinkle structure on the fiber surface. The goal is to obtain synthetic fibers. Another object of the present invention is to obtain fibers having characteristics such as whiteness and water absorption that cannot be achieved by cellulose acetate fibers or synthetic acrylic fibers alone.

Means for Solving the Problems> The present invention resides in a novel method for producing acrylic synthetic fibers, characterized in that cellulose acetate is 10 to 50 weight #4.

In the present invention, especially cellulose acetate is 20 to 40% by weight.
The amount of the acrylonitrile copolymer is preferably 80 to 60% by weight, and if the amount of cellulose acetate is less than 10% by weight, the dry touch and linen-like texture that is the object of the present invention cannot be obtained.

On the other hand, if the weight exceeds 50, the fibrillation of the resulting fibers becomes significant, which is not desirable in terms of quality.

(If it exceeds 70% by weight, spinnability will decrease significantly.

Mixed condition! ! The objective K of the present invention can be achieved if the surface area is non-uniform.

The mixing may be carried out not only by mixing one of each of the two types of polymers, but also by mixing two or more types of polymers for only one or both of them.

Furthermore, in addition to the acrylonitrile copolymer and cellulose acetate, plastic substances, white skin improvers, heat stabilizers, titanium oxide, etc. are added for the purpose of improving spinnability, drawability, and yarn properties.
- Of course you can get it.

Cellulose acetate used in the present invention is cellulose diacetate, cellulose triacetate, and an acrylonitrile copolymer containing at least 80 g of acrylonitrile, which is copolymerized with other acrylonitriles. It is a copolymer consisting of possible ethylenically unsaturated monomers.

Examples of the ethylenically unsaturated monomers include acrylic acid, acrylic esters, methacrylic acid, methacrylic esters, acrylamides, methacrylamides, vinyl acetate, vinyl chloride, vinylidene chloride, vinylpyridine, and styrene. , itaconic acid, itaconic esters, ethylene sulfonic acid, allyl sulfonic acid, methallyl sulfonic acid, styrene sulfonic acid, and salts thereof.

The acrylonitrile copolymer may be obtained by a known polymerization method, and its preferred molecular weight range is 300.
00-80000.

Common solvents used in the present invention include organic solvents such as dimethylformamide, dimethylacetamide, etc., as well as inorganic solvents such as concentrated nitric acid, zinc chloride aqueous solution, rhodan soda aqueous solution, etc., and are not particularly limited.

In addition, in the spinning dope, even if water is added within a range where the spinning dope becomes a gel, it will not be possible to prevent the spinning dope from becoming a gel.In wet spinning, an aqueous solution of the above-mentioned organic solvent or an organic solvent such as isopropyl alcohol, methyl alcohol, kerosene, etc. is used as a coagulation bath. Although the above-mentioned inorganic solvents can also be used, an aqueous solution of the solvent used in the spinning dope is particularly preferred because it is economical from the viewpoint of solvent recovery. From the viewpoint of economical solvent recovery and ease of handling, organic solvents such as dimethylformamide, dimethyl V sulfoxide, and dimethylacetamide are particularly preferred.

Wet spinning can be carried out under the same conditions as for ordinary acrylic synthetic fibers. That is, it is sequentially stretched through several stages of bathtubs,
After washing with water, prevent sticking in the next drying process.
An oil agent is applied as necessary to prevent static electricity problems, etc., followed by normal drying and heat treatment.

Other major features of the fibers obtained according to the present invention are whiteness and water absorption. It is known that fibers yellow and lose their whiteness when exposed to heat during the melting process, fiber drying process, etc. However, it is worth mentioning that mixing cellulose acetate can improve whiteness. It is the right thing to do.

Regarding water absorption, if the acrylonitrile copolymer cellulose toacetate is mixed with dimethylformamide, for example, the acrylonitrile copolymer becomes the sea and the cellulose acetate forms the islands, so-called seabirds. A porous acrylic synthetic fiber in which cellulose acetate is dispersed in a striped manner along the fiber axis is obtained.

According to the present invention, *, a has a water absorbency that is not observed in a single fiber of an acrylonitrile copolymer,
It also has a Hikone texture, making it a suitable material for summer clothing.

<Examples> The present invention will be explained below using examples. Note that in the examples, ``chi'' means weight.

The effect of whiteness was confirmed by the following evaluation method. The opened fibers are measured with a Tokyo Denshoku TO-5D colorimeter, and the value of 1) (L: The closer to 100, the whiter it is;
OK, the closer it is, the blacker it is, b... Substitute it into + to calculate 1.1) [. The smaller the bb value, the higher the whiteness.

Examples Acrylonitrile 92.7fi, vinyl acetate vy, a and sodium methallylsulfonate α! An acrylonitrile copolymer containing 1% of the acrylonitrile copolymer was dissolved in dimethylacetamide, and an acetic acid settvo-X was dissolved in dimethylacetamide. A spinning stock solution was prepared by adjusting the concentration to 896. The spinning stock solution was prepared such that the polymer concentration in the spinning stock solution was 23 in total, including the acrylonitrile copolymer and V-rose on acetic acid. This spinning stock solution was extruded and coagulated at 40°C through a spinning nozzle V with a hole diameter of 08 mφ and a number of holes of 400 into a 50% dimethylacetamide aqueous solution, and then the undrawn yarn was stretched 5.0 times in hot water at 95°C. After washing and applying a spinning oil, it was dried with a heated roller at 140°C.

This fiber was subjected to mild sterilization in saturated steam at 2.5 u/2 to obtain a fiber having a fineness of 3 denier/filament. Table 1 shows the results of comparing the textures of the obtained fibers. The product containing 10 to 4 al of cellulose acetate had a Hikone texture with a dry touch.

No. table Table 2 Table 2 also shows the results of measuring the whiteness of the obtained fibers.

The fibers obtained according to the present invention were found to have excellent whiteness.

In addition, the results of measuring the moisture content remaining in the fibers after immersing the obtained fibers in water &C for 10 minutes and then dehydrating them in a centrifugal dehydrator at 5000 rpm for 10 minutes are shown in the third table.
Shown in the table. As can be seen from Table 3, the fibers according to the present invention were also found to have high water absorption.

Table 1 <Effects of the Invention> The acrylic synthetic fiber according to the present invention has an excellent crisp linen-like texture and is suitable for use as a material for summer clothing.Furthermore, it has high water absorbency and is therefore suitable for the indoor clothing field.

Claims (1)

[Claims] A novel method for producing acrylic synthetic fibers, which comprises wet spinning a spinning solution prepared by mixing 10 to 50% by weight of cellulose acetate and 90 to 50% by weight of an acrylonitrile copolymer in a common solvent.