JPH06207311A - Acrylic synthetic fiber excellent in ultraviolet permeation-preventing property and its production - Google Patents

Abstract

PURPOSE:To obtain an acrylic synthetic fiber having washing resistance and wide range of fiber processing conditions and excellent in ultraviolet permeation- preventing properties and a method for industrially readily and inexpensively produce the acrylic synthetic fiber. CONSTITUTION:The acrylic synthetic fiber excellent in ultraviolet permeation- preventing properties comprises plate titanium oxide in an acrylic synthetic fiber. In producing the acrylic synthetic fiber by wet spinning, the plate titanium oxide is uniformly dispersed in an organic solvent and then, the dispersion is added to an organic solvent solution of a copolymer containing acrylonitrile and the resultant stock solution is spun.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an acrylic synthetic fiber having excellent ultraviolet ray permeation resistance and a method for producing the same.

[0002]

2. Description of the Related Art Generally, it is well known that ultraviolet rays are electromagnetic waves having a wavelength shorter than visible light and having a wavelength of 200 to 400 nm. C: 200-290n
m), medium wavelength ultraviolet light (UV-B: 290 to 320n)
m), long wavelength ultraviolet light (UV-A: 320 to 400 nm)
It is divided into. Since most of UV-C is absorbed in the atmosphere and does not reach the ground, UV-A and UV-B having a wavelength of 290 nm or more adversely affect the human body. In particular, UV-B causes erythema formation and pigmentation due to acute inflammation, is extremely harmful, and its action on the human body is said to reach 1000 times that of UV-A.

Although acrylic synthetic fibers and the like have an ultraviolet shielding effect, although they are not sufficient, they often transmit ultraviolet rays under direct sunlight and often cause sunburn due to sunlight.

Therefore, as a method for preventing ultraviolet ray transmission, conventionally, microcapsules containing an ultraviolet ray absorbing agent or an ultraviolet ray absorbing agent is applied by coating or the like, or an ultraviolet ray reflecting agent such as granular titanium oxide is directly added to the spinning dope or in advance. A method in which the particles are dispersed in a solvent and then mixed and spun is used.

[0005]

However, the method of simply applying the microcapsules containing the ultraviolet absorber or the ultraviolet absorber has the drawback that the product itself is not durable and the product itself becomes defective, and the ultraviolet reflection The method of adding the agent to the spinning dope has a drawback that the effect cannot be obtained unless the ultraviolet reflector is added in a considerably large amount.

The inventors of the present invention have completed the present invention as a result of earnest research to improve the above-mentioned drawbacks.

An object of the present invention is to provide an acrylic synthetic fiber which has washing resistance and has a wide range of fiber processing conditions and which is excellent in ultraviolet ray permeation preventing property. Still another object is to provide a method for industrially easily and inexpensively producing such an acrylic synthetic fiber having excellent ultraviolet ray transmission preventing properties.

[0008]

The acrylic synthetic fiber of the present invention, which is excellent in ultraviolet ray permeation preventing property, is characterized in that the acrylic synthetic fiber contains plate-shaped titanium oxide.

In the method of the present invention, when the acrylic synthetic fiber is produced by wet spinning, the plate-shaped titanium oxide is uniformly dispersed in an organic solvent and then added to an organic solvent solution of a copolymer containing acrylonitrile. It is characterized by spinning this.

The present invention will be described in detail below.

The copolymer containing acrylonitrile used in the present invention is not particularly limited, but it contains at least 40% by weight of acrylonitrile as a constituent unit, and preferably has a fiber-forming ability. That is, 40% by weight or more of acrylonitrile and other vinyl monomers such as acrylic acid, methacrylic acid, or their alkyl esters, vinyl acetate, vinyl chloride, vinylidene chloride, sodium allyl sulfonate, sodium methallyl sulfonate, vinyl sulfone. 6 with appropriate combination of acid soda, sodium styrene sulfonate, sodium 2-acrylamido-2-methylpropane sulfonate, etc.
Examples thereof include those copolymerized at a ratio of 0% by weight or less. Especially 80 wt% or more of acrylonitrile and 20 wt%
The following copolymers of vinylic monomers and sulfonic acid group-containing monomers, or acrylonitrile of 40% by weight or more and vinylidene chloride and sulfonic acid group-containing monomers of 20 to
A copolymer containing 60% by weight is preferable.

The titanium oxide used in the present invention must be plate-shaped. Although its action is not clear, it is considered that the plate-like titanium oxides are arranged in parallel to the fiber axis direction by stretching after spinning, and excellent ultraviolet ray transmission preventing property can be obtained even in a small amount. The amount of addition is 0.1 to 10.0% by weight, preferably 1.
0 to 5.0% by weight is included. When the content of the plate-shaped titanium oxide is less than 0.1% by weight, the fiber cannot be sufficiently provided with an ultraviolet ray preventing effect, and when it exceeds 10% by weight, the fiber performance is deteriorated and the spinnability and spinnability in spinning are deteriorated. To do.

According to the method of the present invention, the plate-shaped titanium oxide is uniformly finely dispersed in an organic solvent using a disperser, and then added to an organic solvent solution of an acrylonitrile copolymer and spun to form a plate-shaped titanium oxide in the fiber. Is uniformly contained. Examples of the solvent used in the method of the present invention include organic solvents such as dimethylformamide, dimethylacetamide, dimethylsulfoxide, and acetone. Any known wet crusher may be used as the dispersing device, but a flow tube crusher such as a sand grinder, a pearl mill, a gren mill or a dyno mill is suitable for continuously adding the dispersion liquid to the spinning dope.

In the present invention, the dispersion concentration of the plate-shaped titanium oxide in an organic solvent solution is 5 to 40% by weight, preferably 15 to 3%.
It is 0% by weight. If the concentration is less than 5% by weight, the concentration of the spinning dope is lowered, the spinnability is lowered and the fiber properties are lowered, depending on the amount of the plate-shaped titanium oxide added. Again 40
When it exceeds the weight%, a good uniform finely dispersed state cannot be obtained, and it becomes difficult to industrially manufacture.

Spinning may be carried out under the same conditions as for ordinary acrylic synthetic fibers, passing through several stages of baths, followed by sequential drawing, washing with water,
Dry and post-process.

[0016]

EXAMPLES The present invention will be specifically described below with reference to examples. In the examples, "(%)" means "% by weight".

Examples 1 to 3, Comparative Examples 1 to 4 Acrylonitrile (AN) / methyl acrylate (M
A) / 2-acrylamido-2-methylpropanesulfonic acid sodium (SAM) = 91.2 / 8.0 / 0.8, an acrylic polymer dimethylformamide (DM)
F) A solution was prepared. After plate-shaped titanium oxide was dispersed in DMF with a sand grinder, it was added to the above acrylic copolymer solution in an amount shown in Table 1 and sufficiently stirred with a homomixer to prepare a spinning dope.

The above stock solution was spun into a 60% aqueous DMF solution at 20 ° C., and while being desolvated, it was washed with water after stretching and then densified by applying an oil agent. After crimping this fiber,
Wet heat treatment was performed at 120 ° C.

In the comparative examples, those different from the above-mentioned addition amount were added to the acrylonitrile copolymer (Comparative Examples 1 and 2) and granular titanium oxide (particle diameter 0.007 to 0.007).
0.20 μ) was dispersed in DMF and then added to an acrylonitrile-based copolymer (Comparative Examples 3 and 4).

Using the ultraviolet ray preventing fiber thus obtained, a spun yarn of 2/26 count was formed, a knitted fabric having a plain cloth structure was prepared by a circular knitting machine of 1/8 G, and the UV shielding rate was measured. UV blocking rate is Shimadzu's own recording spectrophotometer UV210.
It was evaluated by measuring the transmittance at 360 nm using 0. In addition, the spinning operability was judged by combining the filtration pressure, the single yarn breakage, the roller winding, etc. when manufactured under the conditions described in the examples, and was evaluated as "◎", "○", "△", "x". It was done in stages. The results are shown in Table 1.

[0021]

[Table 1]

Example 4 A DMF solution of an acrylic copolymer consisting of AN / vinylidene chloride (VCl ₂ ) / sodium allyl sulfonate (SAS) = 57/40/3 was prepared. The plate-shaped titanium oxide used in Example 1 was dispersed in DMF with a sand grinder, and then added to the acrylic copolymer solution so that the amount of plate-shaped titanium oxide was 5.0% with respect to the acrylic polymer. Then, the mixture was sufficiently stirred to prepare a spinning dope.

The above spinning solution was spun into an aqueous solution of DMF at 25 ° C. and 55%, washed with water while being drawn with a solvent, added with an oil agent, and dried and densified. After crimping the fibers, they were subjected to a heat treatment at a moist heat of 115 ° C.

The obtained fiber was knitted in the same manner as in Example 1, and the UV shielding rate after 0, 5, 10 and 20 times of home washing was measured. As a result, as shown in Table 2, even after 20 times of washing, It showed a good ultraviolet ray transmission preventing effect.

[0025]

[Table 2]

The washing was carried out under the following conditions. Commercially available small electric machine use neutral detergent 1g / l bath ratio 1: 100 temperature x time 40 ° C x 5 minutes water wash 10 minutes dry 80 ° C x 1 hour

[0027]

EFFECT OF THE INVENTION The acrylic synthetic fiber of the present invention, which has an excellent ability to prevent the passage of ultraviolet rays, has an excellent effect of preventing the passage of ultraviolet rays and has the fiber performance of ordinary acrylic synthetic fibers as it is, and the ultraviolet ray transmission after washing. There is almost no decrease in the prevention effect. Further, the method for producing an acrylic synthetic fiber excellent in ultraviolet ray transmission preventing property of the present invention can industrially easily and inexpensively produce such a fiber under ordinary acrylic synthetic fiber production conditions and equipment.

The fibers obtained by the present invention can be used by mixing with other fibers such as ordinary acrylic synthetic fibers, polyester, nylon, cotton, rayon, wool, etc. Since it can be used for a wide range of purposes such as clothing and socks, it is extremely meaningful in industry.

Claims (2)

[Claims] 1. An acrylic synthetic fiber having an excellent ultraviolet ray permeation preventive property, characterized in that the acrylic synthetic fiber contains plate-shaped titanium oxide. 2. When the acrylic synthetic fiber is produced by wet spinning, the plate-shaped titanium oxide is uniformly dispersed in an organic solvent, and then added to an organic solvent solution of a copolymer containing acrylonitrile, which is then spun. A method for producing an acrylic synthetic fiber which is excellent in ultraviolet ray permeation preventing characteristics.