Pulp molding wet processing
Wet processing refers to the process of injecting the pulp into the forming mold through a pipeline after the pulp is crushed, and the excess water is absorbed by vacuum to form a wet tray and then immediately transferred to the hot pressing forming mold for rapid extrusion and drying.
Advantages: The wet processing has high production efficiency for environmentally friendly tableware, which is transferred and shaped immediately after forming, and the production speed is fast; the wet processing has a moisture content of about 65-75%, a high moisture content, and a longer vacuum adsorption time; The surface of the degradable tableware products produced by the wet processing is smooth and delicate, beautiful; the disposable lunch boxes produced by the wet processing have thinner walls, higher density, and save space.
Disadvantages: it is not easy to draw or demold the disposable lunch box products with a small slope; the product with a small R angle or a small slope has a higher rate of breaking the net; it consumes more heat energy.
Application of wet processing
1. High-quality work package, also called high-end paper-plastic work package, are mainly molded products with smooth and beautiful outside formed by wet processing。These products are mostly suitable for high-end electronic lining boxes, high-end razor packaging boxes, and high-end clothes. Packaging boxes, glasses cases, etc., such products require extremely high precision, beautiful appearance, and higher added value than other ordinary wet-pressed products.
In order to be more beautiful and increase the added value of the packaged products, this type of product can also be printed in color to better display the packaging effect.
2. Food packaging containers, which are what we often call disposable degradable tableware, generally refer to wet-press molded products containing food such as plates, bowls, boxes, cake dishes, etc., generally made of plant fibers such as wheat straw, sugar cane, etc. Add food grade water and oil repellent dosage.
It can be used in daily catering, hotel dine-in, food delivery, etc. Such products require microorganisms and heavy metals to meet food-grade requirements. They are produced in dust-free workshops and have a clean and beautiful appearance.
3. Medical trays, mainly wet-pressed products, are mostly used for the stacking of registered equipment and drugs. They are required to be produced in a dust-free workshop. The microorganisms must be controlled in accordance with medical standards and dust-free and vacuum-sealed.
4. Entertainment toys refer to masks, painted toys, etc., which can be produced by two processes of semi-dry processing and wet processing. They require good smoothness on the outside and can retain the applied dyes, making the hand feel more delicate and smooth.
Pulp molding dry processing
The dry processing refers to the process of injecting the pulp into the forming mold through a pipe after pulping. After the excess water is absorbed by vacuum to form a wet tray, the moisture of the wet tray is reduced to about 40% by natural drying or through a special drying channel. This method is mostly used to produce low-grade pulp egg trays, pulp work packages and other products.
Advantages: low thermal energy consumption, reducing energy consumption; mostly pulp products, recyclable waste paper, low cost and low price; thicker product thickness, good shock and pressure resistance; packaging electronic products can prevent static electricity.
Disadvantages: dry processing products (including semi-dry process) have rough surface and poor aesthetics; the wall thickness is thicker and take more space.
Application of dry processing
1. Ordinary work package generally refers to the lining of low-end electronic products, egg tray, and fruit tray. The product is rough, and its main function is shock resistance and pressure resistance, and does not require high aesthetics.
2. Agricultural packaging mainly refers to flower pots, seedling cups, egg trays, etc. Most of these products are produced using the dry processing of yellow pulp and newspaper pulp. Such products have low hygiene requirements and low product stiffness requirements , But requires better waterproof performance.
3. Medical packaging, dry processing is mainly used in places with lower requirements such as bedpans, urinals, and kidney-shaped discs.