JPH0424219A - Insect-proof acrylic synthetic fiber - Google Patents

Abstract

PURPOSE:To provide the title fiber good in resistance to washing, dry cleaning and moist heat, containing a specified amount of dehydroacetic acid, with the extraction rate with an alcohol-benzene mixture not higher than a specified value. CONSTITUTION:The objective fiber containing 0.05-3 (pref. 0.1-2)wt.% of dehydroacetic acid with the 60min-extraction rate by immersion with an alcohol- benzene mixture accounting for <=40 (pref. <=30)wt.% of the dehydroacetic acid content.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application J] The present invention relates to insect-repellent acrylic synthetic fibers that have good washing resistance, dry cleaning resistance, and moist heat resistance.

[Problems to be solved by the prior art and the invention J Acrylic synthetic fibers are widely used in the clothing, bedding, and interior decoration fields. BACKGROUND ART In recent years, as lifestyles have become more Westernized, carpets, curtains, blankets, etc. are widely used in airtight, hot and humid rooms. It is easy for dirt and dust to adhere between the fibers of carpets, curtains, blankets, sheets, and futons, and they also become habitats for ticks, bedbugs, etc.
It is said to be a breeding ground for dust mites. In particular, when mites breed, their carcasses are scattered into the air and become a major social problem, as they are said to cause childhood illnesses. For this reason, there has been a desire to develop insect repellent fibers that do not breed insect pests such as mites and are safe for the human body.

Conventional methods for controlling pests on carpets, curtains, and blankets include exposing them to sunlight, spraying them with insecticidal chemicals, or treating them with smoke. These processes have the drawbacks of being complicated and having a short shelf life.

There is also a method of imparting insect repellent properties by spraying or impregnating fibers with insect repellents and insecticides, but these methods have limited effectiveness and are said to lose their insect repellent properties when washed. There are drawbacks.

Also, JP-A-59-. Publication No. 163426 and Japanese Unexamined Patent Publication No. 1983
As in Japanese Patent No. 59117, there is a method in which a swollen gel of acrylic synthetic fibers is impregnated with an insect repellent or a machine-based insecticide and then dried and densified. However, with these methods, the insect repellent effect is significantly reduced due to heat treatment such as steaming during fiber processing, perhaps due to the lack of affinity between acrylic synthetic fibers and chemicals, or because many chemicals are used in combination. This has the disadvantage that post-processing conditions are limited.

The present inventors completed the present invention as a result of intensive research in order to improve these drawbacks.

An object of the present invention is to provide an acrylic synthetic fiber that has excellent insect repellency, washing resistance, dry cleaning resistance, and moist heat resistance.

[Means to solve the problem]

The insect repellent acrylic synthetic fiber of the present invention contains 0.05 to 3% by weight of dehydroacetic acid based on the fiber weight of the acrylic synthetic fiber, and contains 30% by weight of dehydroacetic acid in an alcohol-benzene mixture.
It is characterized in that the extraction rate by immersion at °C for 60 minutes is 40% by weight or less of the content of dehydroacetic acid.

The acrylic polymer used in the present invention contains at least 40% by weight of acrylonitrile, and any polymer can be used as long as it has 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 allylsulfonate, sodium methallylsulfonate, and vinylsulfonic acid. Examples include those obtained by copolymerizing a suitable combination of soda, sodium styrene sulfonate, sodium acrylamide-2-methylpropanesulfonate, etc. in a proportion of 60% by weight or less. In particular, a copolymer of 80% by weight or more of acrylonitrile and 20% by weight or less of a vinyl monomer and a sulfonic acid group-containing monomer,
Alternatively, a copolymer containing 20 to 60% by weight of vinyl chloride and/or vinylidene chloride and a sulfonic acid-containing monomer is preferable.

Furthermore, the acrylic polymer may contain a resin that is incompatible with the acrylic polymer, such as cellulose acetate, polystyrene, acrylonitrile-styrene copolymer, polyvinyl acetate copolymer, and polyvinyl butyral. Particularly preferred is the acrylic polymer containing 2 to 30% by weight of cellulose acetate.

In the present invention, the content of dehydroacetic acid is 0.05 to 3
The weight percent is preferably 0.1 to 2 weight percent.

If the content of dehydroacetic acid is less than 0.05% by weight, its insect repellent effect will be insufficient, and if it exceeds 3% by weight, the insect repellent effect will be saturated, and the extraction rate of dehydroacetic acid extracted with a solvent will increase. Washing resistance, dry cleaning resistance, and heat and humidity resistance are also reduced, and the spinnability of the fiber is also reduced.

In the present invention, the extraction solvent alcohol/benzene mixture is a solvent with an alcohol/benzene volume ratio of 1:2 as defined in JTS L-1015.

To measure the extraction rate, accurately weigh 3 g of a chopped fiber sample, place it in a 300 mA Erlenmeyer flask with a stopper, and add alcohol and alcohol.
Add 100g of benzene extract and seal. Control the temperature in a constant temperature water bath at 30°C for 60 minutes.

Take out the Erlenmeyer flask, shake it well, and then concentrate the extract if necessary. This liquid is analyzed by gas chromatography or liquid chromatography to quantitatively analyze the concentration in the extract based on the peak area of dehydroacetic acid, and the amount A of dehydroacetic acid extracted per 1 g of the initial sample is determined.

On the other hand, accurately weigh 2 g of the same cut sample,
Place it in a 00mj+ stainless steel pressurized cell and add alcohol.
Add 50g of benzene extract and seal. This pressurized cell was temperature-controlled for 60 minutes in a 120°C oil bath, cooled, shaken and stirred, then opened, and the extraction solvent inside was analyzed by gas chromatography or liquid chromatography in the same manner as above to quantify dehydroacetic acid. Analyze and determine the dehydroacetic acid content B in the Ig sample.

The extraction rate (%) of dehydroacetic acid from fibers is determined by the following formula.

Extraction rate (%) = A/BX 100 In the present invention, the solvent alcohol/benzene mixture (7
) The extraction rate of the dehydroacetic acid after immersion at 30°C for 60 minutes was 4.
0% by weight or less, preferably 30% by weight or less. If the extracted dehydroacetic acid content exceeds 40% by weight, the insect repellent effect, washing resistance, dry cleaning resistance, etc. will be greatly reduced, and Dehydroacetic acid is largely removed by heating.

In the present invention, dehydroacetic acid may be used alone or in a mixture with other insect repellents, insect repellents, insecticides, synergists, antibacterial agents, or abrasive agents, emulsifiers, oil agents, and the like. However, it is necessary to adjust the conditions so that the extraction rate of dehydroacetic acid does not exceed 40% by weight due to other mixed agents.

In the case of manufacturing the insect repellent acrylic synthetic fiber of the present invention, it is also possible to manufacture it by resin processing the acrylic synthetic fiber, but since the processing conditions are limited by texture hardening and adjustment of the alcohol/benzene extraction rate, in particular the following It is preferable to manufacture by the following method.

In the present invention, by applying dehydroacetic acid to the wet-spun gel-swollen fibers, and then drying and densifying the fibers,
Dehydroacetic acid is contained inside the fiber and allowed to bleed out onto the surface of the fiber.

The solvent for the acrylic polymer used in the wet spinning of the present invention includes organic and inorganic solvents such as dimethylformamide, dimethylcetamide, dimethyl sulfoxide, acetone, zinc chloride aqueous solution, Rodan salt aqueous solvent, and concentrated nitric acid. A v1-containing solvent that tends to produce multiple voids during spinning is preferred.

The method of applying dehydroacetic acid of the present invention is not particularly limited, but it is preferable to apply it in an emulsion state or a fine particle dispersion state in combination with as little as possible of a nonionic, anionic or cationic surfactant. The fine particle dispersion is prepared using a surfactant and a colloid mill or sand grinder (for example, Igarashi Kikai Elf, Willy A Bachof).
By combined use of mechanical dispersion such as 1. It is made into a fine particle state of c+m or less.

If the particle size exceeds 1 μm, the proportion of dehydroacetic acid contained inside the fiber will be small (and the resulting fiber will have poor washing resistance.The ratio of dehydroacetic acid and the combined surfactant is 1 part by weight of dehydroacetic acid). 0.1 to 3 parts by weight, preferably 0.2 to 2 parts by weight of surfactant, particularly preferably 0.3 parts by weight
~1.5 parts by weight. When the ratio of surfactant increases, the extraction rate of dehydroacetic acid with alcohol/benzene mixed solvent increases, and the insect repellent effect, washing resistance and dry cleaning resistance, decreases significantly, and benzoic acid and/or Or, the amount of salicylic acid will be significantly reduced.

In this case, insect repellents and other insect repellents, insecticides, synergists,
Antibacterial agents, solvents, etc., and dehydroacetic acid, alcohol, etc.
It is also possible to use the benzene mixed solvent in a range where the extraction rate does not exceed 40% by weight.

In the present invention, the drying and densification conditions are as follows: In a roller dryer, the surface temperature is 120 to 160°C, preferably ]30
~150°C1 Dry heat 120-180°C in hot air dryer
2 preferably from 13o to 160'c. The drying time is preferably 1 to 7 minutes.

If the temperature is below the above, drying and densification will be insufficient, resulting in significant deterioration of fiber physical properties such as whitening of the fibers, poor dyed color, and decreased strength and elongation. Furthermore, since the fibers are not sufficiently densified, the extraction rate due to the alcohol/benzene mixed melt increases.

Moreover, if the temperature exceeds the above, loss due to scattering of dehydroacetic acid increases.

In the present invention, heat treatment is usually carried out after drying and densification, and the heat treatment temperature is preferably 180'C or lower and/or 125C or lower.

[Effect 1 of the Invention The insect-repellent acrylic synthetic fiber of the present invention has low toxicity and has the same fiber performance and feel as ordinary acrylic synthetic fiber. In addition, it has good resistance to washing and dry cleaning, as well as good moisture and heat resistance against steaming, etc., so the insect repellent is less likely to fall off during product processing such as printing, and post-processing can be done easily.

The insect-repellent acrylic synthetic fiber of the present invention can be used in combination with fibers such as cotton, rayon, wool, regular acrylic, polyester, nylon, etc., to create blankets, sheets, cloaks, etc. that have insect-repellent properties. It is extremely meaningful industrially because it can be used for a wide range of purposes such as carpets, curtains, and futon cotton.

EXAMPLES The present invention will be specifically explained below with reference to Examples.

In the Examples, (%) means "% by weight".

[Example] Insect repellent effect test method> A specimen was spread on the bottom of a glass Petri dish with an inner diameter of 6 cm, and then the test mites were evenly planted together with a medium so that 300 to 500 mites per specimen were placed, and the temperature was kept at 25°C and 175% RH. After 48 hours, the mites are taken out, and the total number of mites in one field of view is directly counted under a 20x stereomicroscope using the visual field method, and then whether or not they are alive or dead is determined. Change the field of view, repeat six times, and calculate the mortality rate using the average.

[Examples 1 to 7, Comparative Example 11 Acrylonitrile (AN)/Methyl acrylate (MA)
/ Sodium methallylsulfonate (SMAS) = 90
．． A dimethylformamide (DMF) solution with an acrylic polymer concentration of 2211% (4/9.0/0.6) was spun into a 160% DMF aqueous solution at 20°C.

After the normal stretching and water washing process, the fibers are in a gel-swollen state.
Dynomil (
Willy A Bachofen).
An emulsion composition in which nonionic and anionic fiber oils were mixed and the concentration of dehydroacetic acid was varied was applied, and dried and densified using a roller dryer at 135"C. Next, mechanical crimping was applied and recuperative heat was applied. Crimp setting was carried out at 110°C.The obtained fibers shown in Table 1 were cut and spun to make knitted fabrics.These knitted fabrics were immersed in an alcohol-benzene mixture at 30°C for 60 minutes to measure the extraction rate and insect repellent effect. Table-1 Examples 8 to 12, Comparative Example 2

Claims (1)

[Claims] Contains 0.05 to 3% by weight of dehydroacetic acid based on the fiber weight of the acrylic synthetic fiber, and has an extraction rate of immersion in an alcohol/benzene mixture for 60 minutes at 30°C of 40% by weight or less of the above dehydroacetic acid content. An insect-repellent acrylic synthetic fiber characterized by: