Making washi (和紙) by hand is one of Japan’s most demanding crafts. The process involves harvesting plant fibers, cooking and beating them into a pulp, and floating sheets one by one on a bamboo screen — all in cold water, typically in winter, when the fibers behave best and the cold slows bacterial growth in the process water.
Step 1: Preparing the Fibers
The primary fiber for most washi is kozo (paper mulberry, Broussonetia kazinoki). The process begins in autumn and winter when the plants are harvested — long, straight-growing stems are cut and the bark steamed to soften it for stripping. The outer dark bark is removed; the white inner bark (shiro-kawa) is what will become the paper.
The white bark is boiled for one to two hours in an alkaline solution (traditionally wood ash lye, now often soda ash) to break down the pectin and lignin bonding the fibers together. After boiling, the material is rinsed thoroughly in running water. The craftsman then sits at a low table and picks out impurities by hand — knots, dark specks, and incompletely separated fibers — a process called chiri-tori (塵取り, impurity removal). This step is entirely manual and takes hours for a batch that will produce only a few dozen sheets.
The cleaned fiber is then beaten to separate and slightly shorten the individual fiber strands, maximizing the surface area available for hydrogen bonding during sheet formation. Traditional beating used wooden mallets; modern production uses stamping or hollander beaters. The beating time and intensity significantly affect the paper’s final character — more beaten fiber creates a denser, smoother paper; less beaten fiber creates a more textured, “toothy” surface.
Step 2: Forming the Sheet
The beaten fiber is suspended in a large vat of cold water, typically at a ratio of 1:100 to 1:200 fiber to water. To this suspension, the papermaker adds neri — a mucilaginous liquid made from tororo-aoi (hibiscus root, Abelmoschus manihot), which slows the drainage of water through the screen and allows the craftsman time to build up an even layer of fiber. Without neri, the water would drain too quickly for control.
The traditional Japanese sheet-forming technique is nagashi-zuki (流し漉き, “flowing formation”) — the craftsman holds a bamboo screen (sugeta) mounted in a wooden frame (keta) and scoops up the fiber suspension, then rocks the screen forward and back, side to side, in a specific motion that aligns the fibers in multiple directions simultaneously. This is the defining gesture of Japanese papermaking, requiring years to master. The rocking motion layers fibers from multiple directions, creating the characteristic strength and isotropy of washi. The thickness of the sheet is controlled by how much suspension is scooped and how long the rocking motion continues.
By contrast, the Chinese technique (tame-zuki, 溜め漉き) used in most Western papermaking simply scoops up the suspension, allows it to drain uniformly without rocking, and produces a paper with fibers oriented primarily in one direction — stronger in one direction, weaker in another. The nagashi-zuki technique creates isotropic paper (equal strength in all directions), which is why washi resists tearing so well.
Step 3: Drying
Freshly formed sheets are stacked in a pile and pressed overnight to remove most of the water. The sheets are then carefully separated — wet washi adheres to itself, and peeling sheets apart requires skilled hands and patience; tearing at this stage wastes hours of preparation. Each sheet is brushed with a wide soft brush onto a smooth wooden drying board (typically cryptomeria cedar), smoothing out any wrinkles, and the boards are left in sunlight or placed in a drying room.
When dry, the sheet peels cleanly from the board. The surface texture of the dried paper reflects the quality of the screen, the brushing technique, and the drying conditions. Very fine washi (for calligraphy or conservation use) may be dried on heated boards for a smoother finish.
Why Winter Production?
Cold water is essential for quality washi production. Bacterial growth that would cloud and weaken the neri suspension is suppressed below 10°C. The fiber suspension remains clear and controllable. Some washi villages — notably in Fukui, Gifu, and Nara Prefectures — still maintain the tradition of producing paper only from November through March, when river water is cold enough for ideal conditions. This seasonal rhythm means that the finest washi represents not just skilled craft but the convergence of season, climate, and material in a specific place and time.