Hemp, a trending material?

Hemp is one of the oldest crop plants in the world. The fibres of the stalk were made into ropes, the seeds produced culinary oil, and the leaves and flowers yielded essential oil. Even 2,000 years ago, hemp fibres were used to make paper, before they were replaced by cheaper wood fibres. Today, hemp is back: as paper for packaging and labels, but also as sustainable pulp moulded pallets or naturally grown mycelium packaging.

For a long time, cannabis, which is the scientific name, was only mentioned in connection with its intoxicating effects. These are caused by the component tetrahydrocannabinol (THC). Today, over 50 varieties of hemp are certified by the EU for use as cultivated crops, and these only contain a very small amount of THC, however, they feature an impressive amount of fibres, ranging from 30 to 40 percent.

Hemp was already being used to produce paper 2,000 years ago. The Gutenberg bible, which was published in 1455, was made of hemp paper. After having been forgotten for a long period, hemp is now a crop plant that is being cultivated in many parts of Europe once more and is used by the paper industry, among others. However, hemp paper is still a niche product. Only a few paper manufacturers have started using the fibres again, among them the Gmund paper factory in Upper Bavaria. Recently, the paper manufacturer from Lake Tegernsee has even added a paper made from 100 % pure European hemp fibres to their product portfolio. The paper is part of the company's Bio Cycle collection, which already features a hemp paper with up to 50 percent cannabis cellulose farmed in Europe, to which cellulose from fresh fibres or recycled paper fibres is added. Hemp paper is produced without any dye, the fibres are naturally very light in colour and only need a little bleaching. They are also five times longer than wood fibres, and therefore have a higher tensile, tear and wet strength. These features are to improve the circular economy of paper, as hemp fibres can be recycled many more times than normal paper. Gmund believes that the future belongs to hemp paper. Their hemp paper can be used for offset printing or screen printing, enhanced with blind embossing or hot foil embossing, or stamped.

VPF, a specialist for adhesive material from Sprockhövel has worked with Gmund Papier to develop the first self-adhesive label material made 100 % from hemp. With a grammage of 120 g/m2, it is made of pure European hemp fibre, is soft to the touch and is well suited for printing. The label printer Etiket Schiller also uses hemp paper from VPF for their self-adhesive labels. The composition and the use of raw plant material leads to inclusions, which cause slight variations in the colour and look of the paper, but which only emphasise the natural quality of the material, says a spokesperson. The self-adhesive hemp paper labels are intended for use for high quality cosmetics, spirits, wine and organic food.

Cannabis fibres are not only useful for making materials for labels. They're also already being used for insulation, cooling food and medicines during transport. Schaumaplast, a specialist for polystyrene, has just marketed an insulating box line made from natural fibres that uses hemp in addition to grass and wood fibres. The new product line, Thermocon Nature, is made of almost 100 % sustainable raw materials, and the company takes care to avoid using of any edible raw plant materials. A minimal amount of polymer binding fibres is added to the natural fibres, which partially consist of recycled material.

The sustainable packaging by the Dutch company Grown.bio is made by growing mycelial networks. The mycelium grows, among other things, between shives of hemp (or other locally sourced agricultural waste), and becomes a stable packaging item. Hemp shives, the pounded soft wood from the inner core of the hemp stalk, are used as a compostable filler product. During production, the growth is said to be achieved with minimal consumption of energy; all in all the carbon balance is negative, says the company. Using only natural components means that products and packaging are 100 % compostable at home, and decompose at the end of their life cycle. The process uses mycelia binding technology, which was developed and patented in the USA by Ecovative Design. The finished product acts as a shock absorber and protects any product inside it. The material acts as insulation against both heat and cold, is lightweight and water resistant, and it can be produced in almost any design.

Today, even one-way pallets can be produced using industrial hemp as an ingredient. For example, the packaging manufacturer Wiederstein Verpackungen produces lightweight one-way pallets made from pulp moulding. The material consists of waste paper, fresh fibres, or natural fibres like crop hemp. A pulp-moulded pallet looks a bit like an egg carton, can be recycled like paper and doesn't produce any disposal fees. In spite of their light weight, they can carry up to 400 kilograms. They could replace heavier one-way pallets, particularly in air freight. During transport, they are very resistant to impact and sturdy, thus providing optimum protection for any goods stored on them. The pulp-moulded pallet can also be used by packing machines. Wiederstein is among the first manufacturers of packaging in Germany to be able to deliver this product.