With the improvement of people's living standards, the health of home appliances and daily necessities has become the development trend of today. At present, products including many fields such as home appliances and daily life are using antibacterial materials to make various consumer products that are beneficial to the health of consumers, such as antibacterial refrigerators, antibacterial plastic packaging, and antibacterial textiles. The antimicrobial effect of the antimicrobial material depends on the type and amount of antimicrobial agent added to the material. Antibacterial agents can be divided into organic antibacterial agents and inorganic antibacterial agents according to their different materials. Organic antibacterial agents are traditional antibacterial agents, which are widely used in medical fields and various industrial fields. Inorganic antibacterial agents pass antibacterial ingredients. An ion such as Ag+ or Cu2+ and a compound thereof are combined with an inorganic material. Compared with organic antibacterial agents, inorganic antibacterial agents have high safety, durability, broad spectrum of antibacterial properties, heat resistance, etc., and thus are widely used in various materials.

Antibacterial mechanism of inorganic antibacterial agents

The antibacterial mechanism of inorganic antibacterial agents has two popular explanations. One is the antibacterial mechanism of metal ion elution type, that is, the antibacterial agent slowly releases metal ions during use, and the dissolved metal ions can destroy the cell membrane or cell protoplasm of bacteria. Active enzyme activity, but has an antibacterial effect; Second, the active oxygen antibacterial mechanism, under the action of light, the antibacterial agent and water or air, the active oxygen O-2 and OH??, have a strong redox The effect is to produce a lasting antibacterial effect. 2 ?? Classification of inorganic antibacterial agents Inorganic antibacterial agents are divided into two categories, one is based on inorganic compounds containing antibacterial metal ions as the mainstream, such as silver, copper, zinc and other metal ions, the most antibacterial is Ag+ ion. Such antibacterial agents can be further classified into a zeolite antibacterial agent, a phosphoric acid double salt antibacterial agent, a silica gel antibacterial agent, a bentonite antibacterial agent, a soluble glass antibacterial agent, etc. according to the type of the carrier. Methods for introducing antibacterial components include ion exchange, melting, and adsorption [2]. The second type is a photocatalytic antibacterial agent typified by titanium dioxide. The antibacterial agent is characterized by higher heat resistance than general inorganic antibacterial agents, and must be irradiated with ultraviolet rays and oxygen or water to sterilize. At present, many researchers are working on the development and application of two types of antibacterial agents.

New inorganic antibacterial agent

Silver-loaded glass antibacterial agent WA291 [3] Silver-coated glass antibacterial agent WA291 was first developed by Japan Ishigaki Glass Co., Ltd. and applied for a patent (Ping 1124760), which was soon commercialized. At present, it is widely used in the market of inorganic antibacterial agents in Japan, broad-spectrum antibacterial, and good in safety. It has become one of the widely used antibacterial agents in the plastics industry, and has been used in many refrigerator factories in China. WA291 is a series of antibacterial agents. Its composition can be divided into two major categories: B2O3 series main components are B2O3, SiO2, Na2O and Ag2O; P2O5 series main components are Na2O, P2O5, CaO and Ag2O. Coarse particles are widely used in water treatment, ultrafine particles are used to produce antibacterial fiber products, and finer WA291 products can be used to produce antibacterial transparent PP and PVC products. In addition to being widely used in home appliances, fiber products and water treatment, WA291 can also be used for stationery and toys such as ballpoint pens, paper, computers, etc.; daily necessities such as handrails, dirt cans, cutting boards, etc.; building materials such as paints, mortars, Wallpapers, etc.; ceramics such as artificial glass, sanitary porcelain, etc.

Silver inorganic antibacterial agent HN??300[4]HN??300 is a silver-based inorganic antibacterial agent developed by the Chinese Academy of Sciences Taixing Materials Factory in 1997. It consists of Ag0??16H0??84 Ti2 ( PO4) 3. Its characteristics are: ?? Efficient broad-spectrum antibacterial, can prevent the formation of bacteria, mold and algae in the environment, the amount is only half of other inorganic antibacterial agents. ? ? It has better compatibility with resin than zeolite type and silica gel type antibacterial agent. ? ? High transparency. Due to the special structure of HN?300 and ultrafine particles, it is not affected by transparency when applied to transparent articles. ? ? High temperature resistance. HN??300 can withstand temperatures above 1 300 ??, and

Nature is not affected. ? ? Chemical stability. It is chemically stable over a wide pH range and can withstand multiple washes of anionic surfactants without compromising antimicrobial activity. ? ? Ultra low toxicity, LD50 value is much larger than other inorganic antibacterial agents. HN??300 has a wide range of applications, and has a good application in the fields of plastics, chemical fiber, ceramics, coatings and papermaking. For example, if the polyester containing 0??5% HN??300 is spun into 90 denier fiber, the fiber exhibits excellent antibacterial effect by shake flask shaking method, and the antibacterial rate is more than 80% in 1 h; after 24 h, the antibacterial rate More than 99%. Adding 0?? 2% of this product's PP ultrafiltration membrane does not affect its permeability, but has a good inhibition of algae reproduction. Another example is the use of HN??300 in coatings. The coating per square meter contains 1 g HN??300 for excellent antibacterial and anti-mildew effects.

Inorganic antibacterial agent

It is a new inorganic antibacterial agent introduced by Guangzhou NCM Company. It uses silver and zinc as active substances and ion exchange resin as carrier. It has broad-spectrum antibacterial, antibacterial long-acting effect, low toxicity, excellent compatibility with plastics and fibers, excellent thermal stability and excellent chemical stability. Sexual and excellent weather resistance. Applications for NR antimicrobials include fibers, plastics, coatings and textiles. For example, PP resin containing 1% NR is spun into 90 denier fiber. After testing, the sterilization rate is 99??9%, and the fiber strength is maintained. After washing with anionic detergent for 10 times, the antibacterial effect will not be decline. Then, if the mortar board is immersed in the silane-type hydrophobic emulsion, no NR is added, and the area is more than 1/3 of the hyphae after 20 days; 0??1% NR is added, and no hyphae are found after 20 days.

Silver antibacterial agent

It is a new powder type antibacterial agent AMP introduced by DuPont in the United States, which can meet the antibacterial needs of fibers, plastics, cosmetics and film products. Is AMP using a unique nuclear particle? ? The outer shell structure encloses the core particles with a special antibacterial coating to inhibit microbial growth. The core particles effectively increase the surface area of ​​the active component, thereby reducing the amount of filler, which is not only environmentally friendly but also economical, while lower filler loading also reduces the effect on color and opacity. The protective coating controls the rate of release of the active ingredient to provide an appropriate level of antimicrobial activity and maintain antimicrobial durability. The core particles may be titanium dioxide, barium sulfate or zinc oxide. Titanium dioxide is used in opaque systems, barium sulfate is used in transparent systems, and zinc oxide is used to enhance antifungal activity. The antimicrobial coating can be silver, copper oxide and zinc silicate. Silver is used for antibacterial, copper oxide, zinc silicate for antifungal. Depending on the nuclear particles and the antibacterial coating, AMP can be made into different grades such as AMP?? T558 is coated with silver, copper oxide and zinc silicate on titanium dioxide, and AMP?? B240 is coated with silver and copper oxide on barium sulfate. , AMP?? Z200 is coated with silver on zinc oxide.

Antibacterial agents and related products

It is a commercial code of silver-loaded zeolite, silver-loaded zinc-zeolite, and silver-loaded copper-zeolite inorganic antibacterial agent. The product was first introduced in 1984 by the Shinagawa Fuel Company of Japan and quickly commercialized. The new antibacterial products made of Zeomic antibacterial agents, such as antibacterial home appliances, antibacterial plastic products, antibacterial coatings, antibacterial ceramics, etc., are very popular. Among zeolites such as silver-loaded, zinc-loaded and copper-supported zeolites, silver-loaded zeolites have the strongest killing ability against Gram-negative bacteria and positive bacteria. The new Zeomic products researched and developed at home and abroad, especially by Japanese companies, are numerous. Such as antibacterial rags and mops made of 1% ~ 3% Zeomic 40% ~ 85% cotton, 15% ~ 60% polyester crude fiber; from PET, Zeomic (2%), adipic acid, diethylene glycol Kneading, making felt, toothbrush, towel, curtain and surgical line; using antibiotic sanitary tube and shower tube with Zeomic, waterproof silicone oil and PVC. In short, Zeomic related products are increasing and applications are becoming more widespread.

Nano inorganic antibacterial agent

There are two types of nano-antibacterial agents, one is metal nano-oxide which has antibacterial activity. It is represented by TiO2 and ZnO. They generate active oxygen in water and air under ultraviolet irradiation and have strong chemical activity. Can react with a variety of organic matter, so that most of July 2001 Liao Liling et al: New inorganic antibacterial agent? ? 63?? Pathogens and viruses are killed. Therefore, they can be applied to the production of antibacterial fibers, antibacterial glass, antibacterial ceramics, antibacterial building materials, etc. [8~10]. Experiments have shown that applying a thin layer of TiO2 on the glass for 3 h can achieve the effect of killing coliforms; after 4 h of light, the toxin content can be controlled below 5% [11]. The other type is mainly composed of silver-zinc composite antibacterial body, with ultrafine TiO2 and SiO2 as carriers. Due to the special effect of ultrafine nano-sized powder particles, the overall antibacterial effect is greatly improved, and the temperature resistance and powder are improved. Body fineness, dispersion and functional effects are fully utilized. Whether it is plastic products or textile, construction and other industries have been widely used [12]. For example, the nano-composite silver antibacterial powder MFS350 developed by Zhoushan Mingri Nano Material Co., Ltd. uses nano-SiO2 as the main raw material, and its average particle size is less than 90 nm. It has the characteristics of high efficiency, rapidity, long-lasting and broad antibacterial spectrum. It can be widely used in chemical fiber and plastics. Supplies, coatings, water treatment, cosmetics and other fields. The MOD nano-high-performance inorganic antibacterial agent developed by Zhejiang Lishui Jindiya Nanomaterials Co., Ltd. is a new inorganic antibacterial agent developed by combining photocatalytic antibacterial technology, metal ion antibacterial technology and nano-preparation technology. MOD nano-high-performance inorganic Antibacterial agents have been widely used in building sanitary ceramics, household appliances, fibers, coatings, etc. because of their functions of killing and preventing bacterial growth, preventing the growth of various microorganisms, and the durability and safety of antibacterial effects. MOD has been applied to various materials, and many related products have been made, such as antibacterial ceramic products, antibacterial cloth fibers, antibacterial masterbatch and antibacterial plastic products, antibacterial cement, antibacterial acrylic and the like.

Research and application prospects

In addition to the above inorganic antibacterial agents, there are many inorganic antibacterial agents with excellent properties, such as the silver-based inorganic submicron particle antibacterial agent Novaron from Japan East Asia Synthetic Co., Ltd., and the Panasonic product AmtekurinZ with silver-loaded zinc oxide as the main component. China's Hebei Shuangling Group Co., Ltd. launched a rare earth activated inorganic antibacterial agent. With the deepening of research on inorganic antibacterial agents at home and abroad, the performance of inorganic antibacterial agents will gradually increase, and its application range will become more and more extensive, and its market is also increasing. The Japanese inorganic antibacterial agent market was 100 t (1.4 billion to 1.5 billion yen) in 1994, 250 to 260 t in 1996, and 400 t (3.6 billion yen) in 1997. In 1999, inorganic antibacterial agents reached 6 billion to 18 billion. JPY. Japan has more than 100 manufacturers of inorganic antibacterial agents. The products of IN??AX and TOTO, the two largest porcelain and sanitary porcelain companies in Japan, have now been mostly converted into antibacterial products [13]. However, there are some problems with the application of inorganic antibacterial agents: ?? Antibacterial stability problems, because inorganic antibacterial agents mostly contain silver ions, which are chemically active, easily converted into brown silver oxide or reduced to black by ultraviolet light. Elemental silver, after discoloration, not only reduces the antibacterial properties, but also makes white or light-colored products unusable; ?? The high cost of using silver is high, which restricts the application in a wider range. Therefore, solving the problem of discoloration of inorganic antibacterial agents and reducing costs are two worldwide problems [14]. To this end, researchers in various countries are working on the improvement of silver-loaded antibacterial agents and the development of inorganic antibacterial agents with superior performance, and achieved remarkable results. For example, Nittetsu Mining Company has developed a silver-zinc-titanium dioxide antibacterial agent that has almost no whiteness before and after UV irradiation or heating. For example, the Japan Institute of Seawater Chemistry has developed an antibacterial agent based on Ca(OH) 2, MgO, Al2O3 and loaded with zinc ions, which is lower in cost than the silver-loaded antibacterial agent, and also has antibacterial and antifungal properties. Two effects. Although its antibacterial performance is slightly inferior to silver-loaded antibacterial agents, its antifungal effect is superior to silver-loaded antibacterial agents, and there is almost no discoloration problem, and its development prospects are expected to be attractive [15]. At present, antibacterial products are recognized by the world as cross-century environmental protection and health products. The comprehensive application of antibacterial products can fundamentally eliminate the cross-contagion of bacteria between humans, humans and animals, and between things. To this end, the demand for inorganic antimicrobials has constituted a huge potential market.

[China Antibacterial Fabric Network ]