The raw material of the paper tray is a three-dimensional paper material formed by molding using waste paper, pulp, sugarcane pulp and other fibers. The raw material of the paper tray has good environmental protection characteristics. Because paper trays have good performance and environmental protection, they are currently widely used. Paper tray technology and the first product first appeared in Denmark, and in the 1960s it was possible to form automated assembly line production, but at that time It has not yet been widely used.
With the maturity of the production process, paper trays can now be produced in large quantities and widely, but in the production process of paper trays, drying is a very important process among them, and it occupies a large production cost. How can the production process improve the drying efficiency of paper trays? ?
The raw material of the paper tray is only about 1% of the pulp of paper fiber. After the wet paper is formed, the moisture content of the wet paper must be reduced to 55% by the mechanical pressing method, and the moisture 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 development of my country’s paper tray industry started relatively slowly, and it has only been around for more than 20 years. However, in the process, the paper tray industry has been developing very rapidly, and the number of paper tray manufacturers on the market has been A lot of increase. And with the advancement of technology, paper trays have gradually developed from low-end products such as simple eggs, fruits, and beer bottles to the direction of lined packaging of products!
