Paper trays from paper tray packaging manufacturers usually refer to paper trays in a broad sense, that is, dry-pressed paper trays. It is a processing method in which paper pulp is used as raw material, and a stainless steel filter mold is used under pressure (negative pressure or positive pressure) to dehydrate the pulp and shape the fibers to produce the required products. Paper tray production mainly includes pulp preparation, forming, hot pressing, molds and other processes. Mold forming includes vacuum forming method and extrusion forming method. Since most of the pulp used in pulp molding uses waste paper as raw materials, it conforms to the environmental protection requirements and the development direction of green packaging. So how can paper tray packaging manufacturers improve the drying rate?
How can paper tray packaging manufacturers improve the drying rate:
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 the paper tray manufacturers, about 3.5-4.5KG of water should be removed per kilogram of the finished paper tray through the drying process, whether it is from reducing the production cost or improving the quality of the paper tray. Said that 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 from the inside to the outside surface in the wet paper tray, and the external diffusion refers to the evaporation of water from its surface. The process of taking away.
