Rio’s most popular anti-mosquito tool

At this year’s Rio Olympics, in addition to the competition for gold and silver, there is another “Made in China” item that is popular. This is the anti-mosquito weapon that helps Chinese athletes block the Zika virus and is called a “national magic weapon” by foreign media: mosquito nets. Mosquito nets were invented by the Chinese as early as the Spring and Autumn Period. What are the things worth paying attention to in modern times? The editor will tell you one by one.

Overview of mosquito net mesh

Mosquito nets are a simple, convenient, economical and practical means of preventing vector-borne infectious diseases. The World Health Organization (WHO) and the Food and Agriculture Organization (GMP) have regarded mosquito nets as one of the three most effective basic methods to prevent malaria, and have distributed mosquito nets free of charge to 88 countries in the world.

At present, the production of mosquito nets and mosquito net mesh is mainly concentrated in Asian countries such as China, Bangladesh, India, and Vietnam, as well as some American countries. my country’s mosquito net mesh industry bases are mainly distributed in strong textile provinces such as Zhejiang, Jiangsu, Fujian, and Guangdong. Product exports and domestic sales are strong. Among them, mosquito repellent nets are mainly exported to various African countries.

Mosquito net mesh fabrics can generally be classified according to style, material, mesh shape, organizational structure, etc. Polyester raw materials are widely available, the technology is mature, the cost is appropriate, and the weaving efficiency is high. It is a commonly used raw material for mosquito net fabrics. Common structures include diamond mesh, hexagonal mesh, square mesh, etc. Some high-end mosquito nets use jacquard weave.

Production methods and equipment of mosquito net mesh

Mosquito net mesh is mostly a warp-knitted mesh fabric, which is a knitted fabric with a warp-knitted structure and a mesh-like appearance on the surface. It is made of knitted warp knitting. Through different yarn laying methods, adjacent longitudinal rows lose contact in certain rows to form a mesh, and the size of the mesh is related to the number of disconnected rows of coils.

Warp-knitted mosquito nets are usually knitted on a single-needle bed warp knitting machine with a small number of combs, usually 2 to 3 combs. KARL MAYER’s HKS 3-M three-comb high-speed tricot machine with gauge number E32 can be specially used to produce elastic/non-elastic plain or small jacquard mesh fabrics. The speed of HKS 3-M can reach 2 000 ~ 2 500 r/min, the working width is 210 inches, and the efficiency of producing low-density base fabrics is higher than that of ordinary Raschel warp knitting machines. The equipment uses a carbon fiber composite needle bed, LEO® (low energy consumption) technology and the KAMCOS® control system.

HKS 3-M Trico Warp Knitting Machine

This machine has a high degree of flexibility. By using the reverse yarn laying method to connect two adjacent braided chain wales, it solves the jacquard limitations of high-speed tricot machines when producing mesh, and the length of the mesh is no longer limited. With this technology, HKS 3-M can produce elastic hexagonal mesh structures, symmetrical mesh structures, mesh structures of different sizes and their combinations.

Domestic and foreign standards related to mosquito net fabrics

There are many factors that affect the quality and performance of mosquito net mesh, including the type of yarn, the strength of the yarn, the surface density of the mesh, the density of the mesh, and the organizational structure. During the production of mosquito net mesh products, yarn types and specifications, weaving density, and organizational structure are selected to ensure that they meet the relevant requirements of domestic and foreign markets and avoid trade risks.

At present, the relevant quality requirements standard for mosquito net products in my country is FZ/T 62014-2009 “Mosquito Nets”. The product performance requirements for mosquito net mesh fabrics are divided into intrinsic quality and appearance quality. Intrinsic quality includes mesh density, fiber content deviation, bursting strength, seam strength, washing dimensional change rate, color fastness, etc.; appearance quality includes specification size deviation rate, color difference, appearance defects, sewing quality, etc. The quality requirements put forward by WHO for long-lasting anti-mosquito net fabrics include mesh density, bursting strength, seam strength, washable dimensional stability and storage resistance. Comparing the two, there are certain differences, as shown in the figure below.

Note 1: Domestic and foreign test methods for various test indicators are different.

Comparison of the intrinsic quality requirements of mosquito net fabrics at home and abroad