WO2008011748A1

WO2008011748A1 - A process for obtaining high valence silver-containing textiles and the products thereof

Info

Publication number: WO2008011748A1
Application number: PCT/CN2006/001441
Authority: WO
Inventors: Rongyu Zheng; Huade Jiang; Xiaoming Luo; Yong Sun; Dongzhao Qiu; Yiduan Zheng
Original assignee: Shenzhen Yuanxing Bio-Pharm Science & Technology Co., Ltd.
Priority date: 2006-06-26
Filing date: 2006-06-26
Publication date: 2008-01-31

Abstract

A process for obtaining high valence silver-containing textile with antibacterial properties is presented. The process includes: 1) preparing H4Ag2O6 solution; 2) impregnating a textile in the solution derived from step 1 for 10 sec. to 30 min.; 3) rolling the textile derived from step 2 by the nip manner with the nip gap in the range of 0.01 - 2.0 mm for controlling the amount of silver carried by the textile; 4) pre-drying the textile derived from step 3 in a pre-drying section at 50 - 120 ºC for 1 - 5 min., and then baking in a main baking section at 100-190 ºC for 5 - 10 min. The products produced by said process are also presented.

Description

High-priced silver antibacterial textile and preparation method thereof

The present invention relates to an antibacterial textile and a preparation method thereof, and more particularly to a high-priced silver antibacterial textile and a preparation method thereof. Background technique

The bactericidal action of silver and silver ions has long been recognized. In the past decade, its application has expanded to various fields of life. There have been many patent reports on the use of fabrics, such as

CN1034090, CN1395828. US3300336 US6436420, JP2000248463, CN1241662 and the like. In the prior art, the antibacterial fabric is directly used with a strong alkali and a strong oxidant in the production process, and silver nitrate is directly used as a raw material. Some of them are made by directly depositing Ag ₄ 0 ₄ produced by the reaction on the fabric, and the uniformity and color of the silver distribution are relatively poor. The silver-containing fabric prepared by CN1241662 is characterized in that ultrafine silver adheres to the fibers of the fabric, so the firmness is poor, and the folding or kneading causes the silver particles to fall off, affecting the antibacterial effect, and at the same time forming uneven color. The preparation of the antibacterial fabric is carried out simultaneously in the preparation of the finishing agent (the solution containing the silver particles), so that the strong alkali, the strong oxidizing agent and the salt produced in the reaction are present in the finishing agent, so that the fabric has more impurities, and the preparation process is more complex.

The bactericidal effects of silver ions of different valence states are different. The bactericidal ability of high-valent silver ions is stronger than that of low-priced silver ions, and is stronger than that of simple silver. U.S. Patent No. 6,436,420 discloses a method for preparing a fabric containing high-priced silver, but the fabric is The preparation is deposited on the fabric in the presence of a strong base and a strong oxidant, so the process is complicated, the content is difficult to control, and the uniformity is also poor.

The Chinese patent application CN1214867, which has been assigned to the present applicant, discloses a preparation method of a silver-containing bactericide, which comprises the following steps: 1) taking an oxide of silver and adding distilled water; 2) after stirring for 15 to 60 minutes, was added dropwise concentrated acid to make a pH of 2-3.5; 3) clarification of at least 2 hours, the supernatant was decanted; 4) was added to the supernatant liquid hydrogen peroxide sterilant is obtained containing H ₄ Ag ₂ 0 ₆ in. The method is characterized by the use of silver oxides, such as silver oxide or silver peroxide, rather than the commonly used silver nitrate, thus avoiding the step of reducing silver ions to elemental silver.

The applicant's Chinese patent application CN1605676 discloses a method which is prepared as described above. H ₄ Ag ₂ 0 ₆ fungicide applied on the fabric method, comprising the steps of: 1) ^ solution containing Preparation 11 _§2 0 _6; 2) was impregnated with the resultant ¾Ag _{_206,} rinsed injection Or coating the textile; then 3) drying the wet textile. Summary of the invention

In order to stably, uniformly and efficiently apply a high-valent silver-containing antibacterial agent to a textile to produce a textile having a highly effective antibacterial effect and uniform color, the present invention proposes a method for producing a high-priced silver antibacterial textile comprising the following steps:

(1) preparing a 3⁄4Ag ₂ ₆ solution;

(2) soaking the target textile in the solution described in the step (1) for 10 seconds to 30 minutes;

(3) controlling the silver content of the textile by using a rolling method, rolling the textile obtained in the step (2), and adjusting the roller pitch to 0.01-2.0 mm;

(4) The textile of step (3) is baked in a pre-drying room at 50-120 ° C for 1-5 minutes, and then baked in a main baking oven at a temperature of 100 to 190 ° C for 5-10 minutes.

Wherein, the present invention utilizes a high-valent silver (H ₄ Ag ₂ 0 ₆ ) solution prepared by the method disclosed in Chinese Patent Application No. CN1214867, soaks various fabrics, and obtains the fabric by a specific condition such as silver content control and color reaction. A silver compound that is higher in valence than divalent silver. The silver Ag3d5 in the fabric obtained by the present invention was determined by the XPS method to be 367·ν (Kumar Kaushik V., J. Electron. Spectrosc. Relat. Phenom. 1991, 56, 273; the metal form of Ag was 368·ν, Ag in Ag ₂ 0 is 367* ⁷ ev, Ag is 367* ³ ev in Ag ₂ 0 ₂ . The concentration of the H ₄ Ag ₂ 0 ₆ solution used in the present invention is 0.002-1.0 w/v%, more preferably 0.01-0.6 w/v%, as needed. Further, in the step (2) of the present invention, the soaking time is more preferably from 10 seconds to 5 minutes. By rolling 1-3 times, the silver content in the fabric can be controlled between 20 ppm and 6 w/w%, and its bactericidal ability is measured by AATCC Test Method 100-1999, which is 99.999% at 24 hours. The pre-drying chamber temperature described in the step (4) is more preferably from 70 to 120 ° C, and the main drying chamber temperature is more preferably from 130 to 190 °C.

The fabric of the present invention may be a natural textile, a synthetic textile, or a mixture thereof. The natural textile which can be used in the present invention may be cotton, wool, hemp, silk, chitosan, or a mixture thereof, preferably cotton, such as gauze, yarn, cotton nonwoven fabric, chitosan nonwoven fabric or the like. Synthetic textiles which can be used in the present invention are synthetic fibers, that is, a rayon fiber, including but not limited to polyester, nylon, polyethylene, and acetate fibers, etc. One of them can be used alone, and a mixed textile of the above products can also be used. The fabric of the present invention may be in the form of a knitted fabric, a woven fabric, a nonwoven fabric, a yarn or a perforated film.

The invention can be made into different silver-containing fabrics according to different uses, and has good stability and strong bactericidal ability, no strong alkali in the production process, no nitrate ions, and no strong oxidant. More specifically, the high-priced silver antibacterial textile prepared according to the method of the present invention has the following characteristics:

1. Good stability and neutral fabric;

2. The uniformity of silver content distribution is good;

3. High antibacterial efficiency;

4. Even color;

5. The silver content of the fabric can be selected according to the requirements of the application. detailed description

First, the stability of the high-priced silver antibacterial textile of the present invention was evaluated by the following method. The cotton non-woven fabric was immersed in a silver (H ₄ Ag ₂ 0 ₆ ) solution having a concentration of 0.40 ± 0.01 w/v% for 1 minute, and then the drum was controlled to have a gap of 1.0 mm and the rotation speed of the drum was 4 m/sec. The non-woven fabric is run at a constant speed in the immersion liquid, and the liquid absorption amount is kept consistent, and the fresh liquid is continuously replenished to ensure that the adsorbed amount and concentration of the silver solution remain unchanged. It was then baked in a pre-drying oven at 80 ° C for 5 minutes and then in a main oven at a temperature of 180 ° for 5 minutes. After the cotton nonwoven fabric thus prepared was stirred in water for 72 hours, the silver content was detected to be 47%, and the sterilization rate was still 99.99% by the AATCC test method 100-1999; the fabric was boiled 10 times in water, each time 10 Minutes (each time changing water), the silver content is still 49.7%, and the sterilization rate is still 99.96%. The fabric prepared by the method of the present invention is irradiated by ultraviolet light for 30 hours and X-ray (25 GY), and sunlight for 25 hours, and its color is stable and the sterilization rate is unchanged. The fabric is boiled or stirred with water, and the pH of the solution is 6-7, which is neutral.

In order to test the uniformity of the silver content distribution in the fabric of the present invention, the results were compared with the applicant's prior application CN1605676. In the preparation process, the present invention adds the step of rolling. By adjusting the pressure at both ends of the rolling, adjusting the gap of the roller with the pad, and adjusting the concentration of the high-valent silver (Ag ₂ 0 ₆ ) solution, it is possible to control the silver content in the silver-containing fabric and ensure uniformity. In the invention, the rotation speed of the drum is strictly controlled, the original cloth is operated at a constant speed during the immersion process, the liquid absorption amount is kept consistent, and the fresh liquid is continuously replenished to ensure the silver. The adsorbed amount and concentration of the solution remain unchanged. The silver content in the all-cotton nonwoven fabric prepared according to the above method of the present invention at different pressures is listed in Tables 1 and 2. Table 1. Test conditions: Roller gap 1.0 mm, pressure equalization 2 times, pressure 0.3 mpa, passing speed 0.3 m/min

Note: Each plate is 0.5 mm thick. Table 2. Test conditions: Roller gap 1.0 mm, pressure equalization 2 times, pressure 0.38 mpa, passing speed 0.3 m/min

_£ above tests proved added steel sheet between two rollers each of the first fixed place into three 4.5 mm thick steel plate, by adjusting the roller gap (actually change the pressure on the fabric) may control fabric Note: The amount of silver.

In addition, under the selected drum pressure and clearance, and constant oven temperature conditions, ensure that each time the silver solution is a stable solution of silver and pH, it can be guaranteed Silver fabrics have a stable silver content.

Table 3 below shows the effect of the concentration of the original solution on the silver content of the fabric under other conditions (roller gap 1.0 mm, pressure equalization 2 times, pressure 0.3 mpa speed 0.3 m/min).

table 3

It is apparent from Table 3 that the silver content in the fabric is closely related to the concentration of the original silver solution.

In the following, a plurality of points are randomly selected on the high-priced silver antibacterial fabric cotton non-woven fabric prepared by the above method of the present invention and the high-priced silver antibacterial fabric cotton non-woven fabric prepared by the impregnation method described in CN1605676, and the points are measured multiple times. The silver content, the results are shown in Tables 4 and 5, respectively, and the concentration of the silver (3⁄4 Ag ₂ 0 ₆ ) solution used in the test was 0.40 ± 0.01 w/v%.

Table 4

table 5

From the data in Tables 4 and 5, the average relative deviations of the silver content on the high-priced silver antibacterial fabric prepared by the method of the present invention and the high-priced silver antibacterial fabric prepared by the impregnation method described in CN1605676, respectively, were 6.23%. And 14.2%. From this it can be seen that the method of the present invention provides a more uniform distribution of silver content in the fabric under conditions of selected drum pressure and clearance and silver solution concentration as compared to the method of the prior application CN1605676.

Using the same batch of cotton non-woven fabric, the inventors also compared the antibacterial properties of the silver-containing non-woven fabrics prepared by different methods, using USP27 to measure the silver content, and the bactericidal ability of the fabric antibacterial property test method FZ/ The sterilization rate was measured by T01021-92, and the results are shown in Table 6 below:

Table 6

Method of the invention CN1605676 CN1241662 US6436420 Preparation of silver-containing method Preparation of method Preparation of non-woven fabric Silver-containing non-woven fabric Silver-containing non-woven fabric Silver-containing non-woven fabric

Ag content

0.16 0.32 0.83 0.24 ( g/mm ² )

Antibacterial rate 99.9 94.8 98.7 91.8 As can be seen from the above table, the silver-containing textile prepared by the method of the present invention can achieve a very good bactericidal effect at a low silver content.

Further, the inventors have further compared the bactericidal effect of the present invention with the different silver content of the fabric prepared in the prior application CN1605676 for 1 hour.

The silver-containing nonwoven fabric of Table 7 was prepared by the following method:

(1) Preparation of H4Ag ₂ 0 ₆ solution; formulated into a 20 ppm, 50 ppm, 200 ppm, 600 ppm series of silver solutions.

(2) soaking the cotton non-woven fabric in the solution described in the step (1) for 30 seconds;

(3) controlling the silver content of the textile by using a rolling method to adjust the drum pitch to 1.0 mm;

(4) The textile of the step (3) was baked in a 100-inch pre-drying oven for 5 minutes, and then baked in a main baking oven at a temperature of 170 ° C for 5 minutes.

The silver-containing nonwoven fabric of Table 8 was prepared by the method of the prior application CN1605676:

(1) A solution containing Ag ₂ 0 ₆ was prepared; and a silver solution of 20 ppm, 50 ppm, 200 ppm, 600 ppm series concentration was prepared.

(2) ¾Ag _₂₀₆ obtained nonwoven fabric was impregnated cotton; and

(3) Dry the textile at 100 °C.

The inhibition rate was evaluated in accordance with AATCC Test Method 100-1999. The bacteria used for detection are Staphylococcus aureus. The calculation method of the inhibition rate is as follows:

Inhibition rate =[(C-A)/C] X 100%

Wherein A represents the number of bacteria after 1 hour of inoculation of the drug-containing sample; C represents the number of viable cells of the blank sample after "0" contact time.

The results are shown in Tables 7 and 8 below. Table 7: Antibacterial effects of silver-containing fabrics prepared by the method of the invention

The number of live bacteria per sample of sample lh inhibition rate cotton blank "0" contact (C) 6.16X10 ⁶

Cotton with silver 500 ppm 3.44X 10 ⁶ 44.16% cotton with silver 1000 ppm 2.32xl0 ⁶ 62.34% cotton with silver 2000 ppm 1 .20X 10 ⁶ 80.52% cotton with silver 4000 ppm 4.0X 10 ² 99.994% Table 8: Antibacterial effect of silver-containing fabrics prepared by CN1605676 method

The antibacterial effect of the silver-containing fabric prepared by the method of the invention is significantly better than the prior application

The bacteriostatic effect of the silver-containing fabric prepared by the method of CN1605676.

In the step (4) of the method of the present invention, the textile is subjected to high temperature treatment in order to prevent recoloration. The invention has strict and uniform temperature control in production, adopts oil conduction heating, multi-point temperature measuring device, and is controlled within a range of ±2 °C of the selected temperature.

The temperature of the main oven (second bake) is selected to be constant, and the time of the selected fabric staying in the main oven is closely related to the uniformity of the color of the silver-containing fabric, the maintenance of the silver valence state and the stability of the physical properties. , but does not affect the amount of silver in the fabric.

Under the conditions of the original high-priced silver (3⁄4Ag ₂ 0 ₆ ) solution concentration of 0.4 ± 0.01 w/v% and the padding pressure of 0.38 mpa., the experimental results are shown in Table 9 below. Table 9

As can be seen from the above Table 9, when the temperature is constant, changing the residence time of the cotton non-woven fabric prepared according to the present invention in the drying room has no effect on the silver content of the fabric, but their color is different; When the residence time is constant, the lower the temperature in the pre-drying room, the lighter the color of the silver-containing fabric. Hereinafter, the preparation method, characteristics and effects of the high-priced silver antibacterial textile of the present invention will be described in more detail by way of examples. It is to be understood that the following examples are merely illustrative of the invention and are not to be considered as limiting. Example 1

Prepare a high-valent silver (Ag ₂ 0 ₆ ) solution according to the method of CM214867 to prepare a silver-containing 0.4 w/v ° / ^ solution; soak the fabric in this solution for 10 seconds - 5 minutes; then, the fabric is required according to the fabric The rolling device with silver content adjusted, the drum spacing is 0.01 mm; then enter the drying room (temperature set at 120 ° C), and after 1-5 minutes, enter the main drying room at 190 Ό for 2-10 minutes. Example 2

The silver ion concentration was formulated to be 1000 ppm. Soak the cotton non-woven fabric in this solution for 5 minutes, adjust the roller spacing of the rolling device to 0.5 mm, roll, and then enter the drying room (temperature set at 50 ° C). After 1 minute, enter the main temperature of 100 Ό. Drying room for 5 minutes. The silver content on the cotton nonwoven fabric was measured to be 36.5 g/cm ² . Example 3

The silver ion concentration was formulated to be 3000 ppm. The chitosan non-woven fabric was immersed in this solution for 25 minutes, the roller spacing of the roller unit was adjusted to 2.0 mm, rolled, and then entered into the drying room (temperature set at 80 ° C). After 1 minute, the temperature was 150 ° C. The main drying room is 10 minutes. Chitosan non-woven fabric was measured on a silver content of 75.8 g / _C m ^2. Example 4

The silver ion concentration was formulated to be 4000 ppm. The woven polyester cloth was immersed in this solution for 4 minutes, the roller spacing of the rolling device was adjusted to 1.5 mm, rolled, and then entered into the drying room (temperature set at 50 ° C), and after 1 minute, the temperature was 175 ° C. The main drying room is 3 minutes. The silver content of the woven polyester cloth was measured to be 86.8 g/cm ² . Example 5

The silver ion concentration was formulated to be 500 ppm. Soak the leech viscose non-woven fabric in this solution 5 Minutes, the roller spacing of the rolling mill was adjusted to 1.2 mm, rolled, and then entered the drying room (temperature set at 100 ° C), and after 1 minute, the main drying room was heated to 150 ° C for 4 minutes. The silver content of the leech viscose nonwoven fabric was measured to be 16.7 g/cm ² . Example 6

The silver ion concentration was prepared to be 20 ppm. Nylon cloth was immersed in this solution for 5 minutes, the roller spacing of the rolling equipment was adjusted to 0.5 mm, rolled, and then entered into the drying room (temperature set at 50 °C). After 1 minute, the main drying room was introduced at a temperature of 120 °C. 2 minutes. The nylon cloth was found to have a silver content of 3.0 g/cm ² . Experimental example

The bacteriostatic rate experiment was carried out using the samples of Examples 2-6 in accordance with AATCC Test Method 100-1999. The bacteria used for detection were Staphylococcus aureus. The calculation method of the inhibition rate is as follows:

Inhibition rate =[(c a Aye] 1 oo%

Among them, A indicates the number of bacteria after 24 hours of inoculation of the drug-containing sample; C indicates the number of viable cells in the blank sample after "0" contact time.

Viable cell count 24 hours after inoculation of cotton blank sample 4.5X10 ^8, and the number of viable cells seeded "0", the contact time is in 6.8X 10 ⁷ th, the former is 6.6 times. The results are shown in Table 10.

Table 10 Solution concentration

Sample number of live bacteria per sample 24 hours Antibacterial rate ppm Cotton blank "0" contact -- 6.8xl0 ⁷ cotton blank culture 24 hours - 4.5xl0 ⁸ Example 2 1000 36000 99.95% Example 3 3000 8000 99.99% Example 4 4000 4000 99.99% Example 5 500 22000 99.84% Example 6 20 346000 99.47% It can be seen from the experimental results that the silver-containing antibacterial fabric produced by the method of the present invention has good antibacterial properties.

In summary, by using the method of the present invention, it is possible to produce high-priced silver antibacterial which has good stability, good uniformity of silver content distribution, high antibacterial efficiency, uniform color, and the silver content in the fabric can be changed according to the requirements of the application. textile. It will be understood by those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. The scope of the invention as defined by the appended claims is defined by the appended claims.

Claims

Claim

A method of making a high-priced silver antibacterial textile, the method comprising:

(1) preparing a H ₄ Ag ₂ 0 ₆ solution;

(3) controlling the silver content of the textile by using a rolling method, rolling the textile obtained in the step (2), and adjusting the pitch of the drum to be 0.01-2.0 mm;

(4) The textile of the step (3) is baked in a pre-drying room at 50-120 ° C for 1-5 minutes, and then baked in a main baking oven at a temperature of 100 to 190 ° C for 5-10 minutes.

2. The method according to claim 1, characterized in that the concentration step H (1) ₄ Ag ₂ 0 ₆ solution is 0.002-1.0 w / v%.

The method according to claim 2, wherein the step (1) the concentration of Ag ₂ 0 ₆ solution is 0.01-0.6 w / v%.

4. The method of claim 1 wherein the soaking time in step (2) is from 10 seconds to 5 minutes.

The method according to claim 1, wherein the rolling in the step (3) is 1-3 times.

6. The method according to claim 1, wherein the pre-baking temperature in the step (4) is 70-120 ° C, and the main drying room temperature is 130-190 ° C.

7. The method of claim 1 wherein the textile is a knit fabric, a woven fabric, a crepe-free fabric, a yarn or a perforated film.

8. The method of claim 1 wherein the textile is a natural textile, a synthetic textile, or a mixture thereof.

9. The method of claim 8 wherein said natural textile comprises cotton, Wool, hemp, silk, chitosan, or a blend thereof; the synthetic textiles include polyester, nylon, polyethylene, acetate, or a blend thereof.

10. The method of claim 1 wherein said textile is a cotton nonwoven fabric

11. The method of claim 1 wherein the textile is gauze.

12. A silver-containing antimicrobial textile manufactured by the method of any of claims 1-11.