Paper molds are three-dimensional paper materials that use waste paper, pulp, sugarcane pulp and other fibers as raw materials, and are molded into three-dimensional paper materials. Due to their good performance and environmental protection, they are currently widely used. With the maturity of the production process, the paper support is currently It can be produced in large quantities and extensively, but in the paper tray production process, drying is a very important process, and it occupies a relatively large production cost. How can the production process improve the drying efficiency of the paper tray?
The raw material of the paper tray is only about 1% paper fiber slurry. After the wet paper is formed, the wet paper must be pressed to reduce the moisture content of the wet paper to 55%, while the water content of the paper tray is as high as 65%-75% after forming. It is difficult to use mechanical methods to reduce the moisture content. In the production process of paper trays, about 3.5-4.5KG of water should be removed from each kilogram of finished paper trays through the drying process, whether it is to reduce production costs or improve the quality of paper trays. , It is of great significance to improve the drying efficiency!
The wet paper mold with paper fiber as the main component is a porous object with capillary structure inside, and moisture exists between the surface of the fiber and the pores of the fiber capillary. The paper support products used for the inner packaging of products generally require good dynamic cushioning properties, and the moisture in them cannot be completely removed by mechanical pressing, but needs to be removed by drying. Therefore, compared with the conventional paper drying process, the drying strength of pulp molded products is very high.
On the one hand, hot air acts as a heat source to provide energy for removing moisture, and on the other hand, it acts as a moisture carrier to take away the moisture that is constantly evaporating. The moisture in the wet paper tray depends on the internal and external diffusion of water. The so-called internal diffusion refers to the migration process of water in the wet paper tray from the inside to the outer surface, and the external diffusion refers to the evaporation of water from its surface. The process of taking away. The dryness rate of the paper support depends on the speed of the internal and external diffusion of the moisture and the balance and coordination between the two. Reasonable process conditions should be established around the above two aspects and the dry physical properties of the paper support product!
The use of paper molds is also becoming wider and wider. Paper mold technology and the first product first appeared in Denmark, and in the 1960s, automated assembly line production could be formed, but at that time it had not yet formed a wide range of use. Until plastic packaging caused a lot of white pollution in daily production and life, when a new type of environmentally friendly packaging material was urgently needed on the market, paper mold packaging received attention. At present, many developed countries such as Europe and the United States have successively developed and promoted this technology. The development of the paper tray packaging industry.
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