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Application of Nano-silver Materials In The Field of Textile Functional Finishing Antibacterial, Antistatic, Anti-electromagnetic Radiation

The application of nano-silver materials to the field of textile functional finishing and the development of multi-functional, high-value-added fabrics will create huge economic and social benefits in the future textile industry. Nano-silver is a new type of nano-material that is under in-depth research and rapid development. It has broad application prospects in the textile industry due to its broad-spectrum and long-lasting anti-bacterial properties/anti-electromagnetic radiation properties/conductivity and absorption of some ultraviolet rays.

 

Application in natural fiber yarn and fabric

The fabrics made of natural fibers have good moisture absorption and are mostly porous fibers, which can provide enough water for the growth of bacteria. At the same time, the surrounding environment can also provide oxygen for the growth of bacteria and promote the reproduction of bacteria. Nano-silver has broad-spectrum and long-lasting antibacterial properties. At present, the antibacterial application of nano-silver in natural fibers is mainly for yarns and fabrics, and the antibacterial function is mainly obtained through finishing.

 

Nano-silver antibacterial finishing of yarn is generally aimed at cotton yarn or wool. For example, on the basis of puffing and pretreatment of cotton yarn with sodium hydroxide, tannic acid-reduced silver ammonia solution is used to load nano-scale silver particles in the micro gaps of the fiber to make The nano-silver particles and fibers are loaded on the yarn through coordination bonds, so that the silver-loaded cotton yarn has good antibacterial and washing resistance.

 

Under acidic conditions, using nano silver sol and acid dyes to dye wool yarns and antibacterial finishing at the same time, not only can improve the dye uptake, color fastness and flexibility of wool yarns, but also make wool yarns have good antibacterial properties.

 

 

According to reports, some scholars now use the reducibility and stability of the fabric itself to reduce the nano-silver particles in situ on the fabric, so that the fabric has good antibacterial and washing resistance. For example, Ma Tingfang uses the reducibility and dispersibility of cellulose macromolecules to reduce the silver nitrate solution in situ to prepare nano silver antibacterial cotton fabric, which has excellent antibacterial effect and washing resistance. After 20 cycles of washing, the antibacterial fabric will affect the large intestine. The inhibitory rates of Bacillus and Staphylococcus aureus are still as high as 98.5% and 94.3%, respectively. Majid Montazer and others also successfully used the reducibility and stability of cellulose to reduce Torrance reagent (silver ammonia solution) to synthesize nano silver. After the fabric treated with nano silver was washed for 30 times, the antibacterial performance was almost unchanged.

 

In addition, some scholars compound nano-silver with other substances, using inorganic-organic compounding method or inorganic-inorganic compounding method, to prepare compound such as nano-silver/polysaccharide quaternary ammonium salt (HACC), nano-silver/titanium dioxide, etc. Compound, and then padding and finishing the fabric to obtain functional textiles with multiple functions. Wang Haiyun prepared silver-loaded nano-TiO2 antibacterial agent in an inorganic-inorganic compounding method and used it for the finishing of cotton fabrics, so that the cotton fabric obtained the dual antibacterial functions of silver ion elution antibacterial and TiO2 photocatalytic antibacterial, and two kinds of antibacterial The effects promote each other, making the antibacterial effect far better than a single antibacterial agent with the same content.

 

Application in synthetic fibers and fabrics

Three types of synthetic fibers such as nylon, acrylic, and polyester are widely used. At present, the application research of nano-silver in synthetic fibers is mainly aimed at these three types of fibers and fabrics. The manufacturing of synthetic fiber functional fabrics mainly includes two methods: spinning functional fibers and finishing, specifically including blending spinning method, dipping (rolling) method and magnetron sputtering method. The direct-spun functional fiber has a long-lasting effect, but the technology is complex and the cost is high; the finishing agent is simple and convenient to use, and is suitable for most fiber textiles. The cost is low, but the washing resistance is relatively low.

 

(1) Blending spinning method

The blending spinning method is to add nano silver particles in the fiber manufacturing process to blend and spin the fiber to make the final fabric have corresponding functions. The blending spinning process has no pollution to the environment and is widely used. Zhang Hua uses ultra-fine hemp rod core powder to prepare nano silver particles and spun them into antibacterial multifunctional nylon. When the powder content is 2%, nylon fiber not only has excellent antibacterial properties, high strength, and good elasticity. , It also has the ability of far-infrared emission and negative oxygen ion release, and the spinnability also meets the requirements.

 

The antibacterial polyester masterbatch is prepared by blending the silver-loaded nano-zinc oxide antibacterial agent treated with T-aminopropyl triethoxysilane and polyester, which is added to the polyester skin layer, and the core-type antibacterial polyester is produced by spinning. This fiber has excellent antibacterial properties, and the sterilization rate of Escherichia coli and Staphylococcus aureus is above 99%.

 

(2) Dipping (rolling) method

Although the blending spinning method is environmentally friendly, it is difficult to prepare a spinnable spinning solution. In contrast, the dipping (rolling) process is relatively simple. Yu Qiaozhen treated the nano-silver particles to polyester fabrics by dipping, and studied its effect on the antistatic properties of the fabrics, and found that nano-silver treatment can effectively improve the antistatic capabilities of polyester fabrics; and different treatment methods have endless effects on the fabrics. Similarly, for example, the effect of the one-bath method in which nano-silver particle treatment and dyeing are performed at the same time is significantly better than the two-step method in which dyeing is followed by finishing.

 

Some researchers have explored a new type of finishing method that allows nano-silver particles to be bonded to the surface of the fiber through chemical bonding, so that the bond between nano-silver and the fiber is stronger. For example, the researchers amidoxim part of the acrylic fiber to make the fiber surface with chelating groups, which can be complexed with silver ions, and then use formaldehyde solution to reduce the silver ions to obtain nano-silver composite acrylic fiber. The killing rate of Staphylococcus aureus and Bacillus subtilis exceeds 99.99%, the antibacterial performance is good, and the original physical properties of the fiber have no obvious changes.

 

(3) Magnetron sputtering method

In order to avoid the waste liquid disposal problem of the dipping (rolling) method, some researchers used the radio frequency magnetron sputtering method to sputter nano-silver film on the surface of the fabric. The magnetron sputtering method is to charge a proper amount of argon in a high vacuum, and apply a DC voltage between the cathode (columnar target or flat target) and the anode (the wall of the coating chamber) to ionize the argon gas, and the argon ions are accelerated and bombarded by the cathode On the surface of the cathode target, the atoms on the surface of the target are sputtered and deposited on the surface of the substrate to form a thin film. This method has the advantages of strong bonding force between the coating layer and the substrate, and the coating layer is dense and uniform.

 

Application in industrial textiles

The application objects of nano-silver in industrial textiles are mainly non-woven fabrics, laminated composite fabrics and composite materials.

 

(1) Application in non-woven fabrics

The use of nano-silver to finish the non-woven fabric can obtain antibacterial properties and anti-electromagnetic radiation properties, which can be widely used in medical, sanitation, automotive interiors, electromagnetic shielding materials and other fields. Similar to synthetic fibers, the nano-silver finishing methods of non-woven fabrics also include blending spinning method, dipping (rolling) method and magnetron sputtering method, the principle of which is the same as described above. Hong Jianhan uses magnetron sputtering at room temperature to deposit nano-silver films on the surface of polyester spunbonded nonwovens to make the fabrics resistant to electromagnetic radiation. As the thickness of the nano-silver films increases, the shielding effect of electromagnetic waves is enhanced. This method expands the application field of nonwoven fabrics, and can be used to develop antistatic materials, conductive materials, electromagnetic shielding materials and fiber sensors.

 

The nano silver antibacterial agent is highly uniformly dispersed and implanted in the spinning solution to blend and spin, so that the fabric can obtain higher stability, antibacterial performance and washing resistance, and then obtain nano silver antibacterial spunlace nonwoven rolls and nano silver Antibacterial needle punched non-woven fabric rolls.

 

Its most extensive application field is the production of medical and sanitary products, such as nano-silver antibacterial masks, antibacterial wipes, medical bed sheets, medical wipes, etc. The latter’s market applications are also very broad, such as automobile compartment/indoor air conditioning antibacterial filter media, clothing linings, etc. , Antibacterial insoles, shoe materials, etc.

 

Application in laminated composite fabric

Laminated composite fabrics are ideal materials for civilian sportswear, cold-proof clothing, field work clothes, military combat uniforms, labor protective clothing and other products. The nano-silver finishing of composite laminated fabrics is mainly achieved by dipping or blending spinning. Researchers at Zhejiang Sci-Tech University used a cross-shaped cross-section polyester fiber material containing nano silver particles as an antibacterial modifier as the outer layer of the fabric, and combed cotton yarn with better moisture absorption as the inner layer of the fabric, using the changes in the fabric structure , Combined with advanced finishing technology, the fabric has multiple functions such as moisture absorption, perspiration, and antibacterial.

 

(3) Application in composite materials

 

The silver/polymer nanocomposite material not only has the excellent characteristics of nano silver and polymer, but also gives the material some new functions, so that it has broad application prospects in many fields such as textiles, electronics, and biomedicine.

 

Conclusion

As a new type of material, nano-silver is used in many fields, especially the textile industry is closely related to people’s lives, which has aroused the interest of many researchers. At present, the application of nano-silver in the textile industry is mainly to obtain antibacterial, antistatic, and anti-electromagnetic radiation functions. As people’s requirements for textile products increase, nano-silver will be increasingly used in functional fabrics, and its application prospects in the textile industry will become broader.

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The Application Of Nano Silver Antibacterial In Clinical Treatment

Nano silver powder is a new type of antibacterial product developed based on nanotechnology. Due to the quantum effect, small size effect and large specific surface area, it has an antibacterial effect that traditional inorganic antibacterial agents can’t match. It has high safety and long-lasting effectiveness. , Is an antibacterial agent with long-lasting and weather resistance.

Regarding the principle of the bactericidal effect of nano-silver, most scholars believe that the specific surface area of ultra-fine silver is very large and presents AG+ in water. Therefore, the bactericidal effect of nano-silver is mainly related to silver ions, which can be related to the -SH in the enzyme protein in the bacteria. It binds quickly to inactivate key metabolic enzymes, making pathogenic bacteria unable to metabolize and die; secondly, nano-silver can bind to DNA bases of pathogenic bacteria and form cross-links to replace hydrogen bonds between adjacent nitrogens in purines and pyrimidines. Which denatures DNA without being able to replicate, leading to inactivation of pathogenic bacteria. The atomic arrangement of nano-silver shows that it is a “medium state” between solid and molecule. This extremely active nano-silver particle has super antibacterial ability and can kill bacteria, fungi, mycoplasma, chlamydia and other pathogenic microorganisms. In addition, nano-silver is a non-antibiotic bactericide, and no bacteria are resistant to nano-silver.

1. Application in burns, scalds, burn skin grafts
The results of skin grafting for dozens of burn patients showed that nano-silver increased the epithelialization rate of reticuloepithelial grafts by 40%, and had a better effect on promoting repair of residual burn wounds. The healing time of the experimental group was significantly shorter than that of the control group. Researchers believe through clinical observations and animal experiments that nano-silver antibacterial medical dressings are a kind of clinical external medicine for burns with strong anti-infective effect, low absorption, small toxic and side effects, and convenient use.

2. Application in dermatology
Nano silver is effective in treating acne vulgaris. The nano-ulcer patch is used to treat I-II bedsores. In comparison with the control, it is found that the active ingredient of the nano-ulcer patch is nano-silver particles, which has super permeability, produces a biothermal effect, improves the microcirculation of the damaged tissue, and eliminates the local area. Edema is conducive to tissue regeneration and wound healing.

3. Application in dentistry
Nano silver antibacterial agent can be used to prevent oral caries and mucosal diseases, and can also solve the problem of easy pollution during the production and use of dental materials.

In summary, due to its quantum effect, small size effect and large specific surface area, nano-silver materials are easily in close contact with pathogenic microorganisms, thereby exerting greater biological effects, so they have high safety, wide antibacterial range, and continuous Advantages such as long sterilization time. However, nano-silver materials are prone to particle aggregation and lose their nano-characteristics under conventional conditions without protective agents, which will affect the antibacterial effect of nano-materials. Therefore, the packaging and storage of nano-silver are also extremely important. For details, please consult Hongwu Nano staff online our website:https://www.hwnanomaterial.com/.

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Nano Silver Used for Conductive Ink

Nano-silver is the main component of conductive ink, its concentration is a very critical issue, because it relates to the ability to achieve good conductivity and whether the smooth printing. If the concentration of silver-containing ink is large, the use of this material for fine inkjet, its high concentration and low viscosity conditions with rapid precipitation trend. In the case of high concentrations and very small particles, the distance between the particles and the particles becomes very small, which makes it difficult to prevent the occurrence of agglomeration. The same weight of particles to form a diameter of 10nm suspended matter than the number of 1μm diameter of the formation of suspended solids to more than 1 million times. Therefore, at higher concentrations, the dispersion and stabilization of nano-silver particles is a key technology to make inkjet conductive ink become a mature product.
The adjustment of the diameter of the silver particles, the surface modification method and the ink formulation can improve the dispersion stability of the silver particles. The nano-silver particles may also be dispersed in ethanol so that it is compatible with diethylene glycol or with the ethylene glycol system to form an alcohol-based dispersion.

In general, silver particles less than 100 nm are called nanosized silver. When the diameter of the silver particles reaches this scale, increasing the relative proportions of the surface atoms with higher energy will cause a sudden change in the properties of the material. This change can be expressed as a change in sintering capacity characteristics or due to a change in the band gap Caused by changes in the electromagnetic properties caused by the electrical properties or optical properties of the huge changes in the screen, such as color and transparency changes. For nano-silver, the critical point of its performance change is related to the diameter of the particles. When the particle diameter is less than 50nm, the sintering performance at low temperature (less than 200 ℃) is obviously enhanced, and the melting point can be reduced to 120 ~ 200 ℃ The Inkjet conductive ink is the use of nano-silver particles low melting point of the characteristics of the development history, which can be plastic substrates, and even paper on the basis of printing and sintering process, excellent performance of the conductive layer. Inkjet conductive inks are mostly made of spherical nano silver.

Due to the presence of tiny particles, the inkjet ink is somewhat similar to the pigment type inkjet ink. Therefore, the solid particles in the ink must meet certain requirements: the maximum diameter of the silver particles should be less than 1/10 of the diameter of the nozzle to avoid bridging and blocking phenomena, taking into account the nozzle shape and the number of operations and other factors Founder, this ratio should actually smaller. At present, many companies inkjet conductive ink silver particle diameter is generally 20 ~ 50nm. This scale of silver particles, both with low melting characteristics, but also to meet the inkjet print on the size of the requirements of solid particles.

Related reading:buy silver nanoparticles   silver nanopowder

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Silver nanopowder for antibacterial

Antibacterial mechanism of nano silver powder

Nano-silver particles can enter inside the micro-organisms, interrupt RNA replication to stop it’s reproduction , meanwhile it attached to the microbial cell wall, the impact of microbial organisms transmission finally cause the cell’s rupture and death.

Advantage of nano silver powder in antibacterial application

1) Disinfection and sterilization effect is good, lasting and have no drug resistance problem.

2) small amount at ppm level nano-silver antimicrobial products means lower cost.

3) without shortcoming of allergies and excessive deposition as traditional silver salt antibacterial agent do.

4) non-toxic to human safety, environmentally friendly.

 

Speak of nano silver powder, it’s like a far away high-technology topic, but speaking of specific, detailed antibacterial applications, we know nano silver particle can be part of our daily life.

 

  1. Food

No doubt people consume food every day, and silver nano particle could take pat in our daily life in the way of antibacterial food container. Since nano silver have an inhibitory effect on the common food contamination bacteria (Gram-positive bacteria, Gram-negative bacteria, yeast, mold, etc.), it is applied to produce antibacterial food containers: nano silver food crisper, nano silver plastic wrap, antibacterial ceramic tableware, antibacterial refrigerator

 

  1. Clothing

Nano silver’s antibacterial works as well as on fabrics, try search nano silver antibacterial socks on your online purchasing platforms, there surly comes out lot of results. In fact, some researchers does experiments and proves that nano silver particle function more than merely antibacterial part, also fabrics’’ anti-static and far infrared performance is also improved by nano silver finishing.

 

  1. Living

Nano silver is also widely used in building materials: Nano silver antibacterial coatings, nano-silver antibacterial paint, etc., they are coated on the surface of the plate can kill the surface attached bacteria, and the antibacterial effect is lasting.

 

  1. Medicine

No doubt that antibacterial work is more critical when it comes to the matter of health. And yes nowadays nano silver particle is maturely applied into medicines. For example: nano silver antibacterial dressings, nano silver antibacterial gel, nano silver antibacterial catheter, nano silver antibacterial equipment, nano silver bone cement, etc. I cannot list them all.

 

Related reading:nano silver antimicrobial   antimicrobial silver nanoparticles

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Application of Nano-silver Antibacterial Agent

Nanotechnology is the 21st century’s most promising emerging technology, widely used in information, biological, pharmaceutical, chemical, aerospace, energy, defense and other fields, which has huge market potential. Nanoparticles are particles in the particle diameter between 1~100nm, also referred to as ultrafine particles. Excellent performance of nanomaterials depends on its unique microstructure. Nanoparticles having a small size effect, surface effect, quantum size effect and macroscopic quantum tunneling effect, which shows a material different from conventional thermal, optical, electrical, magnetic, catalytic and sensitive properties.

Nano-silver material has a very stable chemical and physical properties that has a very excellent performance in many aspects of electrical, optical and catalytic, now widely used in many fields of ceramic materials, environmentally friendly materials and coatings. When silver particles are embedded in the different substrates, the original material exhibits different electrical and optical properties. Nowadays, study on silver nanoparticles is still a hot spot with a wide application. At present, nano-silver antibacterial nonwoven fabric as raw material of a variety of medical, health, household and industrial use antibacterial products have been listed.

On the domestic market, the successful launch of nano-silver wound paste, paste nanosilver burns and has dual protective effect of nano silver antimicrobial masks. In recent years, a seriou of products have developed in market, such as a nano-silver antibacterial sanitary napkins, sanitary pads nano-silver, nano-silver antibacterial diapers etc. The newly developed nano-silver antibacterial deodorant antibacterial socks and various types of air filter media, antibacterial wipes, antibacterial mop, antibacterial wipes and the like. Today because of people’s increasing emphasis on health care, nanosilver has excellent antimicrobial efficacy of its products and more widely. Nano silver can also be applied to antibacterial interior wall paint.

Antibacterial interior wall paint can effectively inhibit and kill harmful bacteria in the environment, reduce environmental microbiological hazards on the human body, thus achieving the purpose of the clean environment, the protection of human health, improve the living environment of great significance. Inorganic antibacterial agent is present advantages in safety, durability, broad-spectrum antimicrobial resistance, heat resistance, etc., to overcome the disadvantages of conventional paint mildew fungicides greater toxicity, a soluble, heat, poor durability, and increasingly draw people’s attention.

Currently there are natural antibacterial materials antibacterial materials, organic materials and inorganic synthetic antibacterial antibacterial materials.

In general, natural antibacterial material has the advantage of high security, but it generally short-lived, poor heat resistance, easy re-processing; synthetic organic antibacterial materials having a wide range antibacterial, sterilization speed, etc., but in general it side effects is relatively large, easy hydrolysis, life is short; nano-silver is an inorganic antibacterial material, from the current situation of people in research and development of nano-silver watch, which has a high safety, good heat resistance, antibacterial wide range continuous sterilization of long shelf life and other advantages.

It is precisely because of the nano silver antimicrobial material having the above characteristics and quantum effects of nanomaterials itself and a small effect size and great specific surface features, it attracts so many researchers to so researches and development.