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Major strains of bacteria in nature
Item | Classify | Strains of fungus |
germs | Gram-positive bacteria | Staphylococcus aureus, Bacillus megaterium, Bacillus subtilis |
Gram-negative bacteria | Escherichia coli, Pseudomonas fluorescens | |
fungi | / | Aspergillus niger, Aspergillus flavus, Aspergillus metamorphosis, Penicillium oryzae, Green wood mold, Chlamydomonas globulus, Candida albicans, Microsporidium ferruginosa, Sporotrichomonas sporangia |
Staphylococcus aureus is the most resistant pathogenic bacterium among the germ-free bacteria and be regard as a representative of Gram-positive bacteria. Escherichia coli is very widely distributed and is a typical representative of gram-negative bacteria.
Candida albicans is a common pathogenic fungus of human skin mucosa, sensitive to drugs, with the characteristics of fungi, colonies resemble bacteria rather than bacteria, but is different from mold, with colonies resemble bacteria, easy to count and observe, often as a representative of the fungus. Aspergillus flavus, Aspergillus niger, Trichoderma globosum is often used as a representative of mold for mold performance testing. Most of the current standard select Staphylococcus aureus, Escherichia coli and Candida albicans as the typical testing for gram-positive bacteria, gram-negative bacteria and fungi.
Methods for evaluating the antimicrobial properties of textiles are mainly divided into two categories: qualitative and quantitative.
The qualitative methods mainly include halo method (agar plate method, agar flat dish diffusion method), parallel scribing method and so on. The quantitative methods mainly include quinine method, absorption method, shake flask method, transfer method, transfer printing method, and so on.
The methods used for the different standards, the nature of the methods, and the antimicrobial effects are mainly listed in below table.
The halo method is the most common qualitative test method, which is adopted by AA TCC90, JIS L 1902 and GB/T20944 .1, etc. The principle is to inoculate the test strain on agar medium and then adhere to the specimen, incubate it for a certain period of time, observe the reproduction of the bacteria and the size of the halo in the sterile area around the specimen, and compare it with the standard control specimen.
Standard number | Method name | Nature of methodology | Effectiveness evaluation |
AATCC 90 | hoopla | Qualitative | Width of inhibition ring |
AATCC 100 | absorption method | Quantitative | Rate of bacteriostatic and bactericidal |
AATCC 147 | parallel delineation | Qualitative | Width of antibacterial tape |
JIS L1902 | hoopla | Qualitative | Width of inhibition ring |
absorption method | Quantitative | Antibacterial value, Sterilization value | |
transference (printing) | Quantitative | Bacteria reduction value (inhibition value) | |
ISO 20743 | absorption method | Quantitative | antimicrobial value |
the law of transference | Quantitative | antimicrobial value | |
transference (printing) | Quantitative | antimicrobial value | |
GB/T 20944.1 | Agar Petri dish diffusion method (inhibition loop method) | Qualitative | Width of inhibition ring |
GB/T 20944.2 | absorption method | Quantitative | Inhibition value, inhibition rate |
GB/T 20944.3 | oscillation | Quantitative | bacteriostatic rate |
FZ/ T 73023 | hoopla | Qualitative | Width of inhibition ring |
Improved quinine law | Quantitative | bacteriostatic rate | |
absorption method | Quantitative | bacteriostatic rate | |
oscillation | Quantitative | bacteriostatic rate |
AA TCC 147 is a relatively quick and convenient qualitative test of the antimicrobial effectiveness of textiles by parallel scribing. Appendix D.6 of FZ/ T73023-2006 is based on the Quinn method of the US and with certain modified. It is a relatively simple and fast test method for bacterial and some fungal tests. It is suitable for soluble or non-soluble antimicrobial textiles with good water absorption and light color.
The bacterial liquid absorption method is suitable for soluble antimicrobial fabrics, or non-soluble antimicrobial fabrics that are more absorbent and require less frequent washing. Typical examples of this method are AATCC100, JIS L1902, FZ/T73023 Appendix D7, GB/T20944.2 and ISO 20743 Method A.
Shake flask method is an evaluation method of antimicrobial performance of non-soluble antimicrobial products. It is to put the sample and control sample into the triangular flask with certain concentration of bacterial liquid, oscillate for a certain time at the specified temperature, determine the concentration of bacteria in the flask before and after oscillation for a certain time, calculate the inhibition rate, and evaluate the antimicrobial effect of the sample. The representative methods include: FZ/ T 73023 -2006 Appendix D8, GB/ T 20944 .3.
The transfer method is a kind of filtering the test bacteria and nutrient broth through the filter membrane together, then put the wetted test sample on the filter membrane with test bacteria, put a weight on the sample to exert a certain pressure, transfer the test bacteria to the sample, and elute immediately and after incubation respectively, so as to evaluate the antimicrobial performance of the fabric. The method is applicable to test the antimicrobial properties of antimicrobial processed textiles that are in the dry state during consumption.
There are two main ways to express the antimicrobial effect: percentage and logarithm.
AATCC100, FZ/T73023 and GB/T20944.3 use percentage for antimicrobial activity, JIS L 1902 and ISO20743 use logarithmic value for antimicrobial activity, and GB/T20944.2 uses percentage and logarithmic value for antimicrobial activity. FZ/ T 73023 – 2006 classifies antimicrobial knitwear into three antimicrobial grades: Grade A, Grade AA and Grade AAA according to the number of washes and the corresponding antimicrobial performance (inhibition rate).
2.2 Testing of antiviral effects:
On August 19, 2014, ISO officially released the “Textile Anti-Virus Testing Standard” (ISO 18184-2014) This standard specifies the test methods for the anti-viral properties of textiles (including woven and knitted fabrics, fibers, yarns, etc.).
In this standard, viruses include.
(i) An enveloped virus,the influenza virus, which can cause respiratory illness in humans.
(ii) A non-enveloped virus, catomavirus, which can cause gastrointestinal illness in humans. It is important to emphasize that the results of a test for one virus cannot be transferred to other viruses due to individual sensitivity.
The methods used to characterize the viral infection values are the viral spot method and the TCID50 method.
ISO18184 uses antiviral activity rate and antiviral activity value to characterize the effect of antiviral, specific operation methods are: antiviral processing samples and control samples without antiviral processing quantitatively absorb a certain amount of virus suspension, 0 contact time immediate elution, and in the specified temperature and humidity conditions after a period of time to elute, the eluate for virus plate counting, calculation of residual in the Number of viruses on samples.
Finally, the rate of antiviral activity of the antiviral fabric was calculated by comparing the number of viruses on the sample at zero contact time with the number of viruses remaining on the antiviral processed fabric after a period of contact time.
The antiviral activity rate or activity value of an antiviral fabric is calculated by comparing the number of viruses on the control fabric without antimicrobial processing after a contact time and the number of viruses remaining on the antiviral processed fabric after a contact time.ISO18184 classifies the antiviral effect, and the antiviral activity value Mv≥3.0 indicates excellent antiviral effect; 3.0>antiviral activity value Mv ≥2.0, indicating an effective antiviral.
Standard number | Method name | Effectiveness evaluation |
ISO18184-2014 | Determination of anti-viral activity of textiles | Antiviral activity value, antiviral activity rate |
The Japanese Committee for Industrial Standards also published a test standard for textile antiviral activity in 2017, JIS L1922-2016 Textiles. Determination of antiviral activity of textiles. The test is similar to ISO 18184-2014 in terms of methodology and testing for antiviral effect.
3.Antibacterial and antiviral applications on textiles
The research and development team of Dymatic Chemical has achieved a series of breakthroughs in 2019 both in cooperation with relevant scientific institutions, including the evaluation of the clinical application effects of antiviral agents, additives emulsification technology, textile application process, and finished product wash-durability.
In February 2020, Dymatic Chemical launched Bacmatic DM-3015N, an antibacterial and anti-viral finishing agent, which was quickly recognized by the market. In the field of textile hygiene finishing, including antibacterial and anti-odor, mite, mildew, mosquito prevention, etc., Dymatic Chemical has formed a series of targeted products to meet the individual needs of different customers.
Including antibacterial hygiene finishing agent Bacmatic DM-3012, anti-mite antibacterial finishing agent Bacmatic DM-3013D, anti-mildew agent Bacmatic DM-3030N, anti-mosquito finishing agent Bacmatic DM-3031N, silver ion antibacterial agent Bacmatic DM-3011N, natural antibacterial agent Bacmatic DM-3015T and so on.
3.1 Antibacterial and antiviral principle of Bacmatic DM-3015N:
Antibacterial and anti-viral finishing agent Bacmatic DM-3015N is a complex of quaternary ammonium salt and other antibacterial components, is a durable antimicrobial agent, can be used in cotton, polyester, nylon fabrics and non-wovens for antibacterial treatment.
Bacmatic DM-3015N has broad-spectrum antibacterial function, and its antibacterial mechanism is to bind with the negatively charged acidic phosphatidylglycerol (PG) on the surface of bacterial cell membrane through the super strong cationic active group, leading to the change of membrane permeability and thus dissociation. At the same time the polymer’s suitable molecular chain length and the high match of the bridging length of the polar negatively charged groups on the cell membrane surface can further enhance its anchoring and destruction effect, which ultimately leads to the dissolution and death of the bacterial contents.
Attacking the spine proteins NA (neuraminidase) and HA (hemagglutinin) on the coronavirus envelope denatures them, while destroying the negatively charged lipid envelope, exposing the RNA and accelerating its degradation, ultimately resulting in rapid virus inactivation.
3.2 Application:
Bacmatic DM-3015N is cationic, can not be used with anionic adhesives, OBAs in the same bath, for polyurethane, resin and other chemicals needs to be used in the same bath, should test the compatibility before production, Bacmatic DM-3015N can be used with cationic silicone softener, water repellent agent in the same bath, does not affect the hand feel, but high dosage of silicone softener may affect the durability, it slightly affect the water-repellent effect. The amount of water-repellent agent should be adjusted before use to meet the requirements.
Functions | Examples of categories | Dosage (owf.) |
Anti-bacterial and anti-odor finish for fabrics | Towels, clothing | 2 ~ 4% |
Antibacterial finishing of home textiles | Table sets, tablecloths, bath towels, shower curtains | 2 ~ 3% |
Antibacterial and antiviral protection | Mask, gloves, protective clothing | 4 ~ 8% |
fungal protection | Underwear, socks | 3 ~ 4% |
The dosage of Bacmatic DM-3015N is 2-8% (owf.), and the temperature is adjusted according to the cloth species and process, generally 120-160°C for heat-setting. The recommended dosage of Bacmatic DM-3015N for different applications is listed above.
3.3 Application performance:
Antibacterial textiles should not be worn to destroy the micro-ecological environment of the human skin mucosa as a premise, if long-term use of textiles dissolved in a large number of antibacterial drugs, a variety of microorganisms on the skin have been killed, the micro-ecological balance of the skin will be destroyed, it will pose a threat to human health and safety. Therefore, people wear daily antibacterial textiles for a long time, should not be confused with medical antibacterial fabric products, one-sided emphasis on the sterilization (or antimicrobial) effect.
Third-party test results show that the DM-3015N finishing of cotton fabric, inhibition loop width of 2.5mm, in full compliance with safety requirements. (National standard GB/T31713 requirements of sterilization ring width <5 mm).
Fabric treated with Bacmatic DM-3015N has good safety, complies with GB/T31713 antibacterial textile safety and health requirement, the acute oral toxicity of SPF level KM mouse LD50 value is higher than 5000mg/kg.BW, is non-toxic, harmless to humans. The results of the acute skin irritation test on New Zealand rabbits were as No irritation.
Treat fabric with 30g/L of Bacmatic DM-3015N, and test the antibacterial effect, after 50 washes, the antimicrobial effect is in line with FZ/T 73023-2006 standard AAA requirements, and the actual test inhibition rate is more than 98%, much higher than the standard requirements.
strains of fungus | Tested inhibitionrate% | Standard Required inhibition rate% |
Staphylococcus aureus ATCC6538 | 98 | ≥ 80 |
Candida albicans ATCC10231 | 99 | ≥ 60 |
Escherichia coli 8099 | 98 | ≥ 70 |
item | Anti-viral activity value | Antiviral activity rate/per cent |
antiviral effect | 3.03 | 99.91 |
Padding 60g/L Bacmatic DM-3015N, test in accordance with ISO 18184-2014 textile antiviral activity of the determination of standards to test the anti-virus effect of finished fabric, test results are shown in above table, anti-virus activity value of 3.03, indicating that the anti-virus effect of the fabric is very good.
四、Conclusion
Bacmatic DM-3015N has excellent antibacterial anti-virus effect, broad-spectrum antibacterial anti-virus, high safety, no stimulation to skin, there are more than 99% of the influenza A H1N1, H3N2 virus killed within 2 hours, after 50 washing, gram-positive bacteria, gram-negative bacteria, fungi still have 95% of the above bacteriostatic rate.