The emergence of varied types of molded fiber as a preferred means of packaging and protecting products can be attributed to several factors including improved molding technologies, processes and equipment, and the increasing need for environmentally friendly and sustainable packaging. Molded pulp is remarkably versatile and a superbly formable material providing endless design possibilities.
While molded pulp may be most readily associated with egg packaging and fast-food drink trays, both of which are examples of Type 2 Transfer Molding, there are in fact several types of molded fiber. The type best suited for your specific project will depend on the product to be packaged and protected. For educational and comparison purposes we provide a brief description of all four types of molded fiber.
Keiding designs and manufactures only Type 1 – Heavy Wall Molded Fiber.
Type 1 – Heavy Wall
Heavy-Wall products, also referred to as Thick-Wall, commonly have wall thicknesses of 1/4″ – 5/16″. The finished surface is moderately smooth, the opposite side coarse. Product definition is moderate since only one forming mold is used. Standard volumes range between 20,000 – 2,000,000 parts annually and typical applications include blocking, bracing and support for products over 10 lbs in weight.
Type 2 – Transfer Molded
Transfer Molded products, also referred to as Thin-Wall, usually have wall thicknesses of 1/16″ to 3/16″. Two forming molds are used, the first to form and the second to transfer; therefore both front and back surfaces are relatively smooth, and product accuracy and definition are good. High-speed transfer molding technology assures high-capacity, and typical applications include egg cartons, drink & fruit trays, electronics and other delicate and lighter weight items.”
Type 3 – Thermoformed
Thermoformed molded pulp products originate from “cure-in-the-mold” technology producing strong, well-defined and smooth-surfaced parts. Wall thicknesses typically range between 1/16″ – 1/8″. Once formed the pulp is captured in heated forming molds which press and further densify the molded pulp product. Parts are ejected from the heated molds in their finished state; no oven drying is needed. Uses are for those where high-definition and appearance are essential.
Type 4 – Processed
Processed molded pulp products are those that have undergone a secondary procedure in addition to the core manufacturing process. Secondary processing might include dying, coating, printing, die-cutting, chemical additions, etc.
*Descriptions for molded pulp types published with permission. International Molded Fibre Association. © 1998-2013