Latex products are widely used in industrial and agricultural production, medical and health care, military industry, culture and sports, and daily life because of their advantages such as ultra-high elasticity, strong tactile sense, good wearing, good orthopedic function and good biological performance.Relatively common latex products mainly include latex gloves, latex condoms, latex balloons, latex rubber tubes, latex fingers, latex rubber silk, etc., also including some latex products with special functions.With the continuous improvement of people's living standard and the progress of social civilization, the vigorous development of the medical and health undertakings, the demand for latex products also increase gradually, at the same time, with the development of science and technology, the improvement of people's life quality and human health and safety awareness, strengthening latex products of quality, health, performance and more and more attention to the correlation of personal health and safety, especially in direct contact with human skin latex products, such as latex gloves, latex condoms, its use of security more attention.Therefore, the market on the inherent quality of latex products put forward higher, updated technical requirements.In order to improve the quality of latex products, and better meet the needs of the market, foreign scientific research, production and inspection engineers from raw materials, production technology, equipment improvement and testing technology, etc., carried out extensive research and development work, constantly improve the quality of the latex products, and developed many new products, promote technological progress and the development of the whole of the latex industry.
This paper briefly introduces the development and technical progress of foreign latex products.
1.Development of latex products
Latex products most enough natural latex as the main raw material to produce, and many such as contained in natural rubber latex allergic water-soluble protein of rubber ingredients, if exceed certain content of water soluble protein in latex, a small number of users (especially white people) skin can produce the allergic reaction, such as erythema, itching and discomfort.At the same time, as talcum powder is often used as mold release agent in the production process, the surface of latex products is covered with powder, and the residual powder on the surface of the products exceeds a certain amount, which will also lead to some allergic reactions and uncomfortable feelings of users. Medical latex gloves are the most prominent.In recent ten years, in order to improve the intrinsic quality of latex gloves and solve the problem of glove allergy, foreign countries have developed gloves with low protein, little powder, no powder, oil resistance and acid and alkali resistance.Malaysia and Japan have successfully developed new latex gloves with low protein content or de-protein natural latex as the main raw material, which has the advantages of low protein content, good grasping performance and long storage period.
2.Development and application of new technology and new materials
Although natural latex has a prominent feature of water-soluble protein, aging resistance (film crystallization) and poor air tightness, but its outstanding comprehensive performance is difficult to achieve other materials.Practice has proved that it is impractical to completely replace natural latex with synthetic materials, and it is impossible to completely replace synthetic latex at this stage or even in a longer period of time.In view of this, it is the preferred way to develop new materials and processes to remove proteins or deproteinize natural latex from raw materials.
In addition to the natural latex gloves developed a new process, in the production of weather balloons also developed a new molding process, that is, the use of thermosensitive molding process to produce weather balloons.The characteristics of this process are: no glue left in the production process, the production of larger size products, such as sounding balloons, its weight is easy to control, uniform film, balloon quality difference is small, do not use calcium chloride, clay coagulant and a large number of talcum powder isolation agent, is conducive to environmental protection and operator health.
3.Equipment improvement and development
The equipment renewal and transformation is the "hardware" basis to improve the production capacity and product quality.In order to reduce the increasing pressure of production cost, foreign countries have speeded up the transformation or update of equipment in the production line of inspection gloves and condoms, and successfully launched the four-row production line of medical inspection gloves, with the daily output increased from 150,000 to 600,000, greatly improving the production efficiency and equipment utilization rate.The chains and fixtures used in the inspection glove production line are also diversified. The metal mold base and connecting parts are made of nylon and modified long glass resin which is resistant to high temperature and acid and alkali.In addition, the design and development of high-efficiency leaching device in the glove production line have laid a technical foundation for the industry to achieve the leaching method to reduce the protein content of natural latex gloves. The multi-dimensional rotating equipment developed in Japan has also been successfully used in the production of heat-sensitive weather balloons.
4. Progress of detection technology
With the development and application of detection equipment and analysis technology, the detection technology of toxic and harmful substances in latex products has also made certain progress.
4.1.Determination of protein and residual powder on the surface of medical gloves by water extraction
4.2.Determination of nitrosamines in latex products
Latex condoms and gloves have become the leading products in latex products due to the large market demand. Foreign countries have carried out product innovation, technical innovation, standard innovation, management innovation, which has made great progress.All kinds of latex gloves meet the needs of industry and agriculture, medical and health undertakings;As the most effective contraceptive, STD and AIDS prevention tool, condom plays an important role in protecting people's health.There are still some shortcomings, but these products such as protein allergy, cut off the virus, nitrosamines, with the extension of storage period the performance dramatically reduce the problems of how to improve the health of the product technical performance, solve in the process of latex products storage performance, reduce the latex products broken ratio, better meet the needs of the industry development, is suspends in front of scientific research and technical personnel in the industry