Tableware and industrial packaging products produced using pulp molding technology are truly environmentally friendly. They are made from industrial waste paper or plant fibers, and the production and usage processes are free from any pollution. Pulp molded products not only play a positive role in replacing disposable plastic tableware but are also widely used in industrial products, especially the packaging of electronic products. They have gradually become the mainstream material for commodity packaging, surpassing foam plastic products as the optimal alternative. The pulp molding industry is entering a period of vigorous development. In this article, we will explore the development trends of this new environmentally friendly material and investigate the possibilities of emerging technologies in the field of pulp molding.
Gradual Development and Application of Intelligent and Unmanned Production Lines
Currently, advanced direct pressing technology is widely used in pulp molding, which enables the basic realization of intelligent and unmanned operations. This process utilizes roll paper or pulp board as raw materials and goes through various steps, including fiber dispersion and molding, pre-pressing of paper sheets, spraying and composite paper sheet formation, final extrusion, and shaping, ultimately producing high-quality pulp molded products.
With the gradual application of intelligence and unmanned technology in the production process of packaging products, such as in the corrugated box industry and packaging printing industry, the development and innovation of intelligent and unmanned pulp molding production lines are bound to mature and become the mainstream trend in the future of pulp molding production.
Gradual Promotion and Application of High-Precision Pulp Molded Products
With the application of pulp molded packaging in areas such as electronic products and gifts, there is an increasing demand for high-end and exquisite appearance and dimensions of pulp products. The key characteristics can be summarized as follows:
(1) Significant improvement in surface smoothness, approaching or reaching the level of injection-molded products.
(2) By installing computer-controlled automatic pulp adjustment systems in the pulp supply process and incorporating multiple impurity removal devices, product contamination and impurities are reduced. The use of spectrophotometers for real-time monitoring of color deviation allows color differences to be controlled within ΔE ≤ 1.
(3) The demolding angle of traditional pulp molding is typically 3° to 5°, whereas the demolding angle of pulp molding can now reach below 2° and even reach 0° with advanced techniques. Multiple pressing processes are often employed, and some manufacturers have developed corresponding molds, enabling one-step molding processes that greatly reduce costs and improve efficiency.
(4) The straightness tolerance of pulp molded products can reach ≤ 0.5 mm, surface roughness can be ≤ 3 μm, and the edge R angle can reach R0.2.
(5) The thickness of box-type pulp molded products has increased from 0.7 mm to 0.8 mm to over 1.5 mm. Their strength can rival industrial cardboard, significantly expanding the application range of box-type pulp molded products. They can partially replace small to medium-sized paper boxes used for packaging cosmetics, gifts, and other items.
Research on Functional Pulp Molded Products
(1) Pulp molded products with preservation functions. By adding antibacterial and sterilizing agents to the pulp material, the shelf life of fruits and vegetables packaged in pulp can be extended. For example, citrus fruits can be preserved for 3 months, and lychees can be preserved for 30 days.
(2) Edible pulp molded products. These products are made from fruits and vegetables as base materials, with the addition of appropriate plasticizers, thickeners, and waterproof agents. The natural color of the fruits and vegetables is retained in the pulp material, and the pulp molding process is used to produce inner packaging products. This type of packaging not only serves its purpose but is also edible, reducing pollution and providing multiple benefits.
(3) The production technology of high-end and refined pulp molded products also provides possibilities for further developing mechanical components made from pulp molding. For example, pulp molding can be used to produce friction plates for clutches and brakes in the machinery industry, lubricating oil filters, and cushioning components.
(4) The production technology of high-precision pulp molded products can also be applied to create materials for house decoration, handicrafts, cultural and creative products, and more.
Research on Pulp Molded Composite Materials
The development of pulp molded composite materials is also a focal point of attention in the industry. As the market demands for product functionality and quality become increasingly complex, relying solely on improving production processes and adding additives is no longer sufficient to meet market needs. It is important to explore the addition of other materials to modify the raw material formulation and enhance product performance in pulp molded products. For example, incorporating nanomaterials or high-strength fiber materials into the raw materials can produce pulp molded packaging materials with special properties. This direction of research holds great potential for the future of pulp molding.
Utilizing Computer Technology for Testing and Analyzing Product Performance and Parameters
The use of computer technology to determine the performance and parameters of pulp molded products and achieve quantitative calculations in process parameter design is crucial for improving the quality and production capacity of such products. Computer technology serves as the foundation for specific product and process design based on these parameters. By quantifying the parameters and utilizing specialized software for modeling, pulp molded products can undergo simulated analysis. This includes calculating the relationships between product processes, performance, and various parameters. Through this approach, optimization design for pulp molded products and their production processes can be accomplished.
Development of Direct Compression Production Process and Equipment
The traditional wet pulp molding process involves dispersing pulp fibers in water and filtering them through a forming screen to create wet pulp molds. In contrast, the direct compression production process involves loosening and dispersing the raw material pulp board in a disintegrator. During the conveying process, latex resin is sprayed, and after forming a loose fiber network on the forming screen, the material is processed into pulp molded products using hot pressing and cutting equipment. The direct compression production process adopts continuous molding to produce pulp molded products. It represents a significant transformation in the pulp molding production method. Compared to the traditional wet forming method, the direct compression production process greatly reduces the energy consumption involved in the wetting, disintegration, forming, and drying of pulp boards.
The direct compression production process for pulp molding is energy-efficient and environmentally friendly, and has gained widespread attention in the industry. Some manufacturers are dedicated to the research and development of direct compression production processes and equipment for pulp molding.
Conclusion
In conclusion, pulp molding holds promising prospects for showcasing its innovative potential in a wider range of fields in the future. For example, in the construction and decoration industry, pulp molding can be used to manufacture eco-friendly wall panels, ceilings, furniture, and other products, providing aesthetic and environmentally friendly solutions for interior environments. In the automotive industry, pulp molding can be applied to interior decoration, components, and packaging, injecting more eco-friendly elements into the automotive manufacturing sector. Additionally, pulp molding can also play an innovative role in aerospace, medical devices, educational toys, and other fields, meeting the diverse needs and challenges of different industries.