InventWood is a materials science company that develops densified wood products under the trade name Superwood. The company was founded by materials engineer Liangbing Hu,^[1] and grew out of research led by Hu at the University of Maryland, College Park. The company is headquartered in Maryland.^[1] The commercial production of Superwood is scheduled to begin in mid-2025.

In 2018, Hu's laboratory reported that partially removing lignin from natural wood and then compressing the remaining cellulose under heat produced a material roughly three times denser than the original timber and an order of magnitude stronger in bending and tension.^[2] The material was commercially named Superwood.

Superwood is produced in two steps. First, boards undergo "partial removal of lignin and hemicellulose from the natural wood via a boiling process in an aqueous mixture of NaOH and Na2SO3" while leaving the cellulose fibres largely intact.^[3] Second, the softened boards are pressed at moderate temperature and pressure, a stage that collapses cell walls, aligns cellulose nanofibrils and allows residual lignin to flow and re-bond, locking the structure in place.^[2] The hot-press stage is typically carried out at about 65 °C (150 °F) and reduces the board’s thickness by roughly a factor of five, further concentrating the cellulose network and raising the bulk density.^[4] The procedure works with many fast-growing softwoods and even with non-woody species such as bamboo.^[5][6]

Laboratory tests and independent assessments have reported tensile strength up to about 50 percent higher than structural-grade steel on an equal-cross-section basis. Because Superwood is significantly lighter, its strength-to-weight ratio is roughly ten times that of steel.^[1] Charpy impact tests show an order-of-magnitude gain in toughness compared with the parent wood, while compression and bending strengths also rise markedly.^[2] Superwood has attained a Class A fire rating and is resistant to insects, moisture, and rot when impregnated with a polymer.^[1] In longer-term ageing trials, the densified wood has also resisted fungal attack and shows slower aerobic decomposition than untreated wood when exposed to soil microorganisms.^[5]

InventWood raised US$15 million in its Series A round led by climate-focused investors such as Grantham Foundation and Baruch Future Ventures, Builders Vision, and Muus Climate Partners.^[1] The company’s first commercial production line is scheduled to begin operation in mid-2025.^[7] The initial market focus is on cladding and facade panels,^[4] and prototype parts are being evaluated for lightweight vehicle interiors, aircraft cabin components, and furniture.^[6][7]

• Pulp and paper industry in the United States