Research NewsOct. 13,2023
Contact: Tsunehisa Mikitsune-miki@aist.go.jp

AIST Technology Makes It Possible To Mold Wood
AIST, one of the largest public research organizations in Japan, focuses on the creation and practicalrealization of technologies useful to Japanese industry and society, and on “bridging” the gap between
innovative technological seeds and commercialization.
Wood-Based Sustainable Composites Group in AIST have been developing basic technologies forwood-based composites aiming at building and automotive applications that improve the energy
efficiency as well as the comfortability based on materials science and industrial aspects.
■About the world’s first technology “wood flow molding process”
The “wood flow molding process” is a patent technology originally developed by AIST. In this shaping
technique,a solid wood contained with specific chemicals is hot-pressed in a mold, causing

deformability and fluidity of wood to make a shape along the mold.
Since wood resources are renewable and sustainable if properly planned forestation and deforestation
are performed, wood-based materials can contribute to global environmental issues such as carbon
neutrality. Toward achieving the 2050 challenge, requirements of application expansion of wood basedmaterials have been increasing, for example wood can be shaped and use like plastic and metalmaterials respectively.
AIST discovered that a solid wood generated a large deformability and showed fluidity under certain
humidity, temperature and pressure conditions on a study of the basic physical properties of plantmaterials, and has developed the technological seed for "wood flow molding" using this phenomenon.
We have been conducting various studies to improve this technology based on composites approachand have tried to make wood to be an industrial material through wood flow molding.
Research & developments have been carried out on the application of flow-molded wood toautomobile interiors, construction, and daily necessities, taking advantage of the characteristics of its
light weight and strength comparable to reinforced plastics, which far exceeds that of natural wood1

properties.
Fig.1 shows a composite process based on impregnation of a functional matter into wood. In thisprocess, a functional matter such as pre-polymer or oligomer introduced into wood cells withadsorbents in the first step, and then polymerized in wood cells. A solid wood in a swollen stateprocessed like impregnation generates large deformability under hot-pressing as shown in Fig. 2. This
plastic deformation is derived from mutual position changes among wood cells along intercellular slip
bands, while there is little damage on wood fibrous cell.

Fig. 1 A composite process based onFig. 2 Large deformability of solid wood

impregnation of a functional matter

under hot-pressing.

into wood.

Fig. 3 illustrates SMC molding process of wood impregnated with a thermosetting resin. (i)Uncured resin-impregnated wood sheets are set up in a hot mold, and then immediately are pressed bya hot punch (ii). During hot pressing, impregnated wood is flowed in a cavity up to complete filling.
After curing SMC molding of impreg wood, a 3 D wood product can be obtained with improved
properties compared to original wood.
Examples of wood based composite prepared by hot pressing of various types of impreg wood areshown in Fig. 4. Using conventional plastic forming as well as polymer composite techniques, resin
impregnated solid wood with higher wood content around 70 % can be shaped which contributes tostorage carbon dioxide as wood elements in the products.
Furthermore pursuing the multi-material process with other industrial materials based on woodcomposite techniques enable creating feasible and scalable applications.
2Fig.
Fig. 33 SMC
SMC molding
molding ofof resin
resin
impregnatedwood(impregwood).
impregnated wood (impreg wood).

Fig.4
Fig.4Examples
Examplesofofwood-based
wood-basedcomposites
compositespreparedpreparedbyby
variousvarioustype
typeofofimpreg
impregwood.
wood.

Link :
https://unit.aist.go.jp/mmri/en/groups/suscom.html
https://www.aist.go.jp/aist_j/press_release/pr2018/pr20180205/pr20180205.html
https://www.youtube.com/watch?v=iz6rWSKyHKE&t=7s3