JP2925628B2 - Manufacturing method of antibacterial fiber - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial application field) The present invention processes a so-called cationic dye dyeable polyester fiber (hereinafter abbreviated as CDPET) having a sulfonic acid group and / or a sulfonate group in a structure, and is used for antibacterial treatment. It relates to a method for imparting properties.

Antimicrobial materials are widely used and used today in every corner of life. On the industrial side, it is becoming indispensable in the food industry such as meat factories, medical sites and the like, and the manufacturing industry of pharmaceuticals and the like. It is believed that its importance will continue to increase with the aging of society in the future.

(Prior art) Polyester fiber (hereinafter abbreviated as PET) is a highly versatile material and is widely used in various industrial fields as well as clothing. However, for PET, there is no effective method of imparting antibacterial properties to the material by surface treatment after molding, and development of such a technique has been awaited for many years.

The idea of treating textiles and plastics with metallic silver or silver compounds to impart antimicrobial properties to them has long been known. However, there have been no examples in which the reactivity of silver ions has been studied in detail, and studies have been carried out even to quantitative studies. As a result, antibacterial materials using silver have been limited to fibers into which ion exchange groups can be introduced in a relatively large amount, fibers into which ion exchange groups can be introduced by processing, and plastics that can be plated. In such a case, it is said that the amount of silver used is required to exceed the economically acceptable range. For example, according to Japanese Patent Laid-Open No. 52-92000, the effective concentration range of silver is 0.1 meq / g fiber or more, and in the examples, 0.69 meq / g fiber of silver is used. This means that a large amount of silver was used, 1% and 7% by weight per fiber, respectively. This has a practical problem in terms of economy.

[Problems to be solved by the invention]

PET has no chemically active groups in its structure. However, for the purpose of improving the dyeability, the sulfonic acid group and / or
Alternatively, there is CDPET into which a sulfonate group has been introduced. However, the amount of sulfonic acid groups and / or sulfonate groups that can be introduced without impairing the performance of the fiber is very small. Therefore, surface treatment of fibers with silver ions or silver with conventional technology is not considered as a practical method, and there are many limited methods of imparting antibacterial properties by injecting antibacterial compounds into PET. Previously employed.

As described above, some PETs have a small amount of sulfonic acid group and / or sulfonate group in the fiber in order to improve the dyeability, and silver ion and metallic silver are added to them by a conventional method. CDPET treated to attach or bind
Has weak antibacterial activity and little sustained effect. The present inventors have further studied the use of CDPET, and as a result, in the conventional technology, most of the silver used does not adhere to the fiber, and even if it adheres slightly to the fiber or the resin, silver and silver are used. It was found that the state of ion attachment was non-uniform, the silver surface area was small, and the aggregated silver ions and silver were easily detached by physical treatment such as washing.

(Means for Solving the Problems) The present inventors have conducted intensive studies on a method for uniformly attaching or bonding silver on CDPET while avoiding silver aggregates, and as a result, the present invention has been completed. .

(1) An antibacterial property characterized in that when a water-soluble silver compound is reacted in water with a polyester fiber having a sulfonic acid group and / or a sulfonate group in the structure, the reaction is performed at a temperature equal to or higher than the glass transition temperature of the polyester. A method for producing a polyester fiber, (2) reacting a water-soluble silver compound in water with a polyester fiber having a sulfonic acid group and / or a sulfonate group in a structure at a temperature equal to or higher than the glass transition temperature of the polyester;
Next, a method for producing an antibacterial polyester fiber characterized by treating with a reducing agent. (3) When reacting a water-soluble silver compound with water in the polyester fiber, the pH of the aqueous solution is adjusted to 5 or less. The present invention relates to the production method according to the above (1) or (2).

CDPET used in the present invention (a sulfonic acid group and / or
Or a polyester fiber having a sulfonate group), it is possible to use a fiber or a resin in which the amount of sulfonic acid groups and / or sulfonate groups is particularly increased. Polyester fabrics and yarns (CDPET) and their yarns are blended can be used.

CDPET is generally a polyester fiber obtained mainly by a dehydration polycondensation reaction between terephthalic acid and / or phthalic acid (derivative) and a polyhydric alcohol and has a sulfonic acid group and / or a sulfonate group in the structure. When the processing of (1), (2) or (3) is performed,
Any CDPET having an amount of sulfonic acid group and / or an amount of sulfonate group capable of adhering or binding 1000 ppm or more of silver can be used. As phthalic acid (derivative), phthalic acid, isophthalic acid, paraoxybenzoic acid, 2-sulfoterephthalic acid and the like are used. As polyhydric alcohols, ethylene glycol, pentaerythritol, oligoethylene glycol and the like are used. I have.

As the water-soluble silver compound used in the present invention, silver nitrate is generally preferable, but silver fluoride, silver perchlorate, silver sulfate, silver lactate, silver tetrafluoroborate, silver acetate, and the like may also be used. it can.

The glass transition temperature of commercially available CDPET varies depending on the type of CDPET, but is generally 70 to 90 ° C. Therefore, usually, if the reaction temperature (treatment bath temperature) is 90 ° C or higher, CDPE
It is higher than the glass transition temperature of T. At normal pressure, the reaction may be carried out while boiling the treatment bath. Also, under pressure 10
The reaction may be performed at a temperature of 0 ° C. or higher. The reaction temperature is not particularly limited as long as it is equal to or higher than the glass transition temperature of CDPET, but in order not to impair the properties of CDPET, 200 ° C.
The temperature is preferably as follows, and particularly preferably 90 to 140 ° C. In order to carry out the method of the present invention, CDPET is generally added to an aqueous solution of a water-soluble silver compound, and the mixture is heated with stirring.
The reaction is performed at a temperature equal to or higher than the glass transition temperature of the added CDPET. In addition, an aqueous solution of a silver compound is heated in advance, and CDPE
After the temperature is equal to or higher than the glass transition temperature of T, CDPET may be added and reacted.

Bath ratio (CDPET: silver compound aqueous solution) is 1: 10-40 (weight ratio)
Is appropriate. The heat treatment time is not particularly limited, but usually 10 to 60 minutes is sufficient.

The amount of the water-soluble silver compound used depends on the amount of silver to be attached or bound to CDPET, the type of CDPET, and the reaction conditions. In the case of a commercially available CDPET, a water-soluble silver compound may be used in such an amount that the amount of silver becomes 1 to 5 times the amount of silver to be attached or bound to the CDPET.

By the above method, the desired antibacterial CDPET having a silver sulfonate group (hereinafter sometimes referred to as the CDPET of the present invention) can be obtained.

The antibacterial CDPET having a silver sulfonate group obtained according to the present invention has little coloring, has little discoloration by sunlight, is hardly reduced by a detergent, and the like, and is very advantageous in considering applications in the field of living hygiene. When coloring is a problem, such as a white cloth, it is preferable to adjust the pH and react in an acidic aqueous solution. The pH can be adjusted using a buffer solution, an acid or the like, but it is not preferable to use a compound such as hydrochloric acid which reacts with silver to cause precipitation. Usually, the pH is adjusted using acetic acid, lactic acid or an acetate buffer solution. The preferred pH range is 1-5.

If the acid is used alone, the acid concentration is defined by the pH. Although the concentration of the buffer solution is not particularly limited, it is usually 0.01
mol / (acetic acid) is sufficient. The antibacterial CDPET thus obtained can be further subjected to a reduction treatment, if necessary, to obtain an antibacterial CDPET to which silver fine particles have adhered. When performing a reduction treatment, a reducing agent having a relatively strong reducing power is preferable. For example, hydroxylamine, hydrazine, sugar-caustic, sodium borohydride and the like can be used. Preferably 0.1 of the reducing agent.
An aqueous solution of 1 to 5% by weight is preferably used in an amount of 2 to 30 times by weight of the antibacterial CDPET having a silver sulfonate group, and the reduction treatment can be carried out by heating at 95 to 100 ° C for 10 minutes or more. . The antibacterial CDPET having a silver sulfonate group to which silver is attached in this way and the antibacterial CDPET to which silver fine particles are adhered show a sufficient antibacterial effect even at a silver content of 1 to 1000 ppm, preferably as low as 10 to 1000 ppm. . As described above, in the conventional method, in order to impart antibacterial properties to the fiber, it was necessary to incorporate silver into the fiber at an extremely high concentration of 1% or 7%. On the contrary,
According to the present invention, surprisingly, a strong antibacterial effect is exhibited despite the low silver concentration of 1 to 1000 ppm, and the washing fastness is also extremely excellent. This is the antibacterial CDPE of the present invention.
In T, silver is uniformly adhered or bonded to the fiber or resin, and silver is not aggregated, and silver is present in a state of very fine particles.

What has been reduced according to the method of the present invention to be metallic silver fine particles is pale yellow, and from this aspect, the fibers and the resin obtained by the method of the present invention can be compared with the prior art product exhibiting brown to dark brown. Is advantageous.

Antibacterial CDPET having silver sulfonate group obtained by the present invention and pale yellow antibacterial CDPET to which silver fine particles are attached
Can be dyed with a cationic dye in an arbitrary color tone by an ordinary method. Alternatively, CDPET may be first stained with a cationic dye by a conventional method, and then imparted with antibacterial properties by the method of the present invention. Furthermore, antibacterial properties can be imparted simultaneously with dyeing according to the method of the present invention by using a cationic dye from which a halogen atom contained carefully is excluded.

Since the antibacterial CDPET of the present invention exhibits a high antibacterial effect even though the concentration of silver is extremely low, it is sufficient to use a small amount of silver, and therefore has no effect on the human body.

The antibacterial CDPET of the present invention can be used as an antibacterial material in any place where there is a possibility of contamination by harmful microorganisms. For example, surgical lab coats, hospital curtains, hospital-equipped beds, sofas, pillowcases, slipper backings,
Alternatively, it can be used for diaper covers, sanitary tampons, and the like.

The antimicrobial CDPET of the present invention may be used alone as it is, or may be used without mixing with a fabric, a knit product, or a nonwoven fabric as a blended or interwoven fabric with other fibers.

(Examples) Next, the present invention will be described with specific examples. However, the present invention is not limited to these examples.
In addition, the test of the antibacterial activity was performed by using St.
aphylococus aureus (K. aureus) or Klebsiella pneumoniae (Klebsiella pneumonia) was allowed to adhere to the test piece, kept at 37 ° C for 18 hours, and then the number of bacteria attached to the test piece was measured. The washing test was carried out by measuring the antibacterial effect of a test piece obtained by repeating the method specified in JIS L 0217 103 30 times, and measuring the amount of residual silver by an atomic absorption method.

Example 1 100 parts by weight of a cationic dyeable polyester cloth having a sulfonate group (standard dyeing temperature: 120 ° C.) was immersed in 3,000 parts by weight of boiling water containing 0.18 parts by weight of silver nitrate, and this state was changed to 30 parts.
Keep for a minute. After cooling, the treated cloth was taken out, washed well, and dried to obtain a polyester cloth having silver sulfonate groups. When the silver content of this cationic dyeable polyester fabric was measured by an atomic absorption method, 840 ppm of silver was recognized.

Evaluation of antibacterial property Take 0.2 g of the treated cloth obtained by the above method and use Staphloco
Normal broth suspension of cas aureus ATCC6583P (Bacteria count 8 ×
10 ⁵ / ml) 0.2 ml is applied.
This was kept at 37 ° C. for 18 hours and extracted with 20 ml of buffered saline containing phosphate. This extract was inoculated on a standard agar medium and the number of bacteria was measured. As a result, 120 bacteria / milliliter were detected in the extract from the treated cloth according to the present invention. On the other hand, the untreated control cloth extract containing no silver contained 6
× contained 10 ⁸ cells / ml bacteria.

Examples 2 to 4 In the same manner as in Example 1, except that the amount of silver nitrate in the reaction solution was changed to 0.09 parts by weight, 0.045 parts by weight, and 0.01 parts by weight instead of 0.18 parts by weight. A treated cloth containing silver in a concentration was obtained. They were evaluated in the same manner as in Example 1. Table 1 shows the results.

Examples 5 to 8 100 parts by weight of the cloth containing silver ions obtained in Examples 1 to 4 are immersed in 500 parts by weight of a 0.5% aqueous solution of hydroxylamine, and boiled for 30 minutes. Thereafter, the cloth was washed with water and dried to obtain a treated cloth in which silver ions were reduced and adhered as metallic silver. Each was evaluated in the same manner as in Example 1.
Table 2 shows the results.

Examples 9 to 12 The test pieces obtained in Examples 1, 3, 5, and 7 were subjected to JIS.
The washing was repeated 30 times according to the method of L 0217 103.
The samples thus obtained were measured for silver content and evaluated for antibacterial activity in the same manner as in Example 1. Table 3 shows the results
Shown in

Examples 13 to 16 Staphylo was added to the treated cloths obtained in Examples 1, 3, 5, and 7.
Klebsiella pueumoniae ATCC4352 instead of cocas aureus
The antimicrobial performance was tested in the same manner as in Example 1 except that 0.2 ml of the ordinary broth suspension (9 × 10 ⁵ cells / ml) was adhered. The extract of the untreated control cloth without silver contained 8 × 10 ⁸ bacteria / ml. Table 4 shows the results.

Example 17 A test piece was obtained and subjected to an antibacterial test in the same manner as in Example 1 except that 0.17 parts by weight of silver lactate was used instead of silver nitrate. The results were almost the same as in Example 1.

Examples 18 to 19 In Example 5, 500 parts by weight of a 0.5% aqueous solution of hydrazine or sodium borohydride was used in place of hydroxylamine.
A test piece was obtained in the same manner as in Example 5 except that 500 parts by weight of the 0.5% suspension was used, and an antibacterial test was performed in the same manner as in Example 1. The results were almost the same as in Example 5 in each case.

Example 20 100 parts by weight of a normal pressure dyeable cationic dyeable polyester cloth having a sulfonate group (standard dyeing temperature of 105 ° C) was mixed with silver nitrate.
It is immersed in 2500 parts by weight of water containing 0.05 part and heated to boiling while stirring. After further stirring for 20 minutes, the mixture was cooled, and the treated cloth was washed with water and dried to obtain a polyester cloth having silver sulfonate groups. When the silver content of this polyester cloth was measured by the atomic absorption method, 301 ppm of silver was recognized. After washing the polyester cloth 30 times in the same manner as in Example 9, the silver content in the polyester cloth was 290 ppm. The anti-bacterial properties of the unwashed polyester cloth and the polyester cloth washed 30 times were evaluated in the same manner as in Example 1. As a result, 135 extracts / ml, 3
In the extract of the polyester cloth after washing 0 times, 118 bacteria / ml were detected. On the other hand, 7 × 10 ⁸ bacteria / ml were detected from the extract of the untreated control cloth containing no silver.

Example 21 Cationic dyeable polyester cloth (standard dyeing temperature: 120
C) 100 parts by weight, containing 0.063 parts by weight of silver nitrate
It was immersed in 1500 parts by weight of a 0 ppm acetic acid aqueous solution (pH = 3.8) and heated to 120 ° C. under pressure while stirring. After stirring at 120 ° C. for 1 hour, the mixture was cooled, sufficiently washed with water, and dried to obtain a polyester cloth having a silver sulfonate group. The silver content of this polyester cloth was 344 ppm.

Example 22 As in Example 21, silver nitrate 0.06 was used instead of 1500 parts by weight of a 100 ppm acetic acid aqueous solution containing 0.063 parts by weight of silver nitrate.
The treatment was carried out using 1500 parts by weight of water (pH = 6.5) containing 3 parts by weight to obtain a polyester cloth having silver sulfonate groups. The silver content in this polyester cloth was 354 ppm.

Each of the polyester cloths obtained in Example 21 and Example 22 exhibited the same antibacterial effect as in Example 20.

Example 23 The color difference between the polyester cloths obtained in Example 21 and Example 22 and the untreated polyester cloth was measured using a color difference meter. Table 5 shows the results.

In Table 5 above, ΔL, Δa, and Δb represent a difference in lightness, a difference in hue, and a difference in chroma from the untreated polyester cloth, respectively.

As is clear from the results shown in Table 5, the polyester cloth obtained in Example 21 is almost the same in color tone as the untreated polyester cloth, but the polyester cloth obtained in Example 22 is lighter than the untreated polyester cloth. Have decreased, and both △ a and △ b have large values. An increase in the value of Δa indicates reddishness, and an increase in the value of Δb indicates yellowishness. The difference between the results in Examples 21 and 22 is due to the pH in the treatment solution.
In the case where coloring is a problem, such as a white polyester cloth, an antibacterial polyester cloth having no color change can be obtained by adjusting the pH and performing a reaction with an acidic aqueous solution.

Example 24 120 parts of a cationic dyeable polyester jersey having a sulfonate group was firstly treated with a cationic dye Kayacryl Red G
Dye red at 120 ° C using 0.3 parts of L. The bath ratio is 1:30
It is.

Next, the cloth dyed red is immersed in 1200 parts of water containing 0.2 parts of silver nitrate, gradually heated, and kept at the boiling point for 30 minutes. Thereafter, after sufficiently washing with hot water and drying, a polyester having a silver-sulfonate group was obtained.

Polyesters treated in this way are also available in Staphylo
It had strong antibacterial activity against cocas aureus and Klebsiella pneumoniae.

Example 25 35 parts of the cationically dyeable polyester cloth to which the silver fine particles are adhered obtained in Example 5 are placed in 400 parts of water in which 0.07 part of the cationic dye Kayacryl Light Blue 4GSL is dissolved.
The temperature was raised to 120 ° C. in a pressure vessel and kept for 40 minutes for dyeing. After cooling, the dyed cloth was taken out and washed sufficiently with water to obtain a blue-dyed polyester cloth, and the antibacterial property was maintained.

Example 26 The procedure of Example 1 was repeated, except that polyester resin particles having a sulfonate group were used instead of the cation-dyeable polyester cloth. The obtained particulate polyester resin exhibited the same antibacterial effect as in Example 1.

(Effects of the Invention) The antibacterial CDPET of the present invention exhibits a strong antibacterial effect and has excellent washing fastness, despite the fact that the amount of silver attached or bound is much smaller than conventional ones. Further, the antibacterial CDPET of the present invention has high safety and does not generate harmful substances due to the imparting of antibacterial property even when incinerated. Furthermore, the antimicrobial CSPET of the present invention has very little irritation to the skin and can be suitably used in applications such as clothing that come into contact with the skin.

Further, according to the present invention, a so-called cationic dyeable polyester fiber having a sulfonic acid group, or a fiber obtained by blending them or mixing and weaving them, can easily and economically impart antibacterial properties to silver. There is almost no problem of fiber coloring due to adhesion or bonding.

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-52-92000 (JP, A) JP-A-59-30963 (JP, A) JP-A-58-120873 (JP, A) 30963 (JP, A) JP-A-56-148965 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) D06M 11/00-11/84

Claims (3)

(57) [Claims] The present invention is characterized in that when a water-soluble silver compound is reacted in water with a polyester fiber having a sulfonic acid group and / or a sulfonate group in the structure, the reaction is carried out at a temperature higher than the glass transition temperature of the polyester. Manufacturing method of antibacterial polyester fiber. 2. A polyester fiber having a sulfonic acid group and / or a sulfonate group in its structure is reacted with a water-soluble silver compound in water at a temperature higher than the glass transition temperature of the polyester, and then treated with a reducing agent. A method for producing an antibacterial polyester fiber. 3. The method according to claim 1, wherein when the water-soluble silver compound is reacted with the polyester fiber in water, the pH of the aqueous solution is adjusted to 5 or less.