一,Plant fiber: a double guarantee of performance and environmental protection
Plant fiber is the main ingredient in molding pulp. Its natural capacity to break down and be replaced makes it a good choice for protecting the environment when packing home appliances. varying plant fibers have very varying physical properties, therefore you should choose the right one based on the structural needs and packaging needs of your home appliances.
1. Sugarcane fiber is the best value for money.
Sugarcane bagasse is a byproduct of the sugar industry. It has a moderate fiber length (0.65–2.17 mm) and is robust, which makes it the most frequent material used to package home appliances. In Guangxi, for instance, the production of bagasse pulp will reach 540,000 tons in 2023, which is 12.7% of the total amount of primary pulp. The packaging for the Huawei Mate 60 Pro phone and the Lenovo ThinkPad X1 Carbon notebook is constructed of sugarcane fiber molding. This is 30% cheaper than plastic and can handle temperatures of up to 95 degrees Celsius for 30 minutes without leaking. Sugarcane fiber is popular because its supply chain is well-developed. Major production locations are Guangxi and Yunnan in China, as well as sugar-producing countries like Thailand and Brazil. This means that raw materials are cheap and the supply is stable.
2. Bamboo fiber is the best choice for high-end packaging.
Bamboo fiber is a medium to long fiber that has qualities that are between those of coniferous wood and broad-leaved wood. It is quite robust, has a very smooth surface, and is great for printing. The Sony BRAVIA XR TV's packaging is composed of bamboo fiber molding, which uses wet pressing technology to achieve an accuracy of 0.2mm. The surface printing clarity is 600dpi, which is what high-end home appliances need for brand display. But bamboo fiber tends to make fluffy fibers, which need to be processed by grinding or blended with sugarcane fiber (typically in a 3:7 ratio) to have the right combination of performance and cost. Jiangxi and Hunan are two of China's bamboo-growing locations. They have created an integrated industrial chain for "bamboo forest planting pulp molding," which cuts the cost of bamboo fiber molding by 25% compared to pure wood pulp.
3. Wheat straw fiber: an example of a circular economy
Wheat straw is agricultural waste that has short fibers, is quite stiff, and is very brittle. To make it tougher, it needs to be blended with long fibers, such sugarcane fibers. Millet ecological chain companies employ wheat straw fiber molding to make air purifier lining. They do this by pressing the material semi-dry to get the moisture content to 35%. This makes the product density 0.6g/cm3 and makes it 15% better at cushioning than EPS foam. Shandong and Henan are two of the primary wheat-growing areas in northern China. They have set up a network for recycling straw. Straw fiber molding costs 10% less than waste paper molding, and burning straw doesn't pollute the air as much.
4. Reed fiber: an inexpensive way to package things for industry
Reed fiber is typically used to cushion the packing of household appliances that don't need to work very well, including brackets for outdoor air conditioning units and trays for washing machine accessories. This is because it has a lot of impurities and doesn't stand up well to water. Haier's low-end refrigerator packaging for the Indian market uses reed fiber molding. This makes the fibers stick together better by treating them with chemical mechanical pulp (CMP), which gives the product a rigidity of 0.8 MPa, which is good for long-distance shipping. Reed fiber is cheaper than sugarcane fiber (20% less) and is easy to get in wetland areas like Jiangsu and Zhejiang in China, where it may be sourced locally.
二, Waste paper fiber: a way to recycle resources
Waste paper fiber is a cheap and plentiful supply of molded pulp, but it needs to be screened and changed to work better.
1. Recycling corrugated paper pulp: the key reason why low-cost cushioning packaging works
Pulping and de-inking treatment can turn corrugated cardboard and cardboard waste into recycled corrugated pulp molds. These molds are used to make low-precision items like egg trays and boxes for household appliances. The packaging for Midea air conditioners is made from recycled corrugated paper pulp molding. The cost of one unit is 0.3 yuan, which is 40% less than plastic packaging. After several cycles, though, the strength of the waste paper fibers goes down, therefore to make them tougher, you need to add 10% to 20% long fibers, like sugarcane fibers.
2. Waste paper pulp: an advantage for printing adaptability
Waste paper pulp is made from pulverized wood pulp and includes short fibers and a lot of imperfections. It is typically used as an inner lining for domestic appliances that don't need to print very well. Gree's electric fan packaging for the Southeast Asian market employs waste paper pulp molding. This makes the surface flatter by treating the pulp with chemicals, which meets export regulations and has a barcode scanning success rate of 99.5%. The best thing about waste paper pulp is that it is very cheap (15% less than recycled corrugated paper pulp) and can break down a lot of old newspapers, which cuts down on pollution in landfills.
三, Composite Materials: The Art of Finding the Right Balance Between Performance and Cost
Molded pulp commonly combines the best features of multiple materials through composite methods to fulfill the different needs of home appliance packaging.
1. Biobased plastic composite made from plant fibers
Huawei employs sugarcane fiber PLA (polylactic acid) composite material to package the Mate 60 Pro. This makes molded pulp more resistant to water. The co-extrusion method makes the PLA coating 50 μm thick, which makes the product three times more water-resistant and meets the moisture-proof standards for high-end electronics. This composite material costs 20% less than pure PLA and can be broken down completely.
2. Composite of plant fiber and inorganic filler
Haier added 20% magnesium hydroxide filler to the refrigerator packaging to make molded pulp more fire-resistant. They then used wet pressing technology to evenly spread the filler throughout the fiber network, which gave the product an oxygen index of 28%, which is the UL94 V-0 flame retardant standard. This composite material costs 15% less than standard bromine-based flame-retardant polymers, and it doesn't release any harmful gasses.
