Traditional Japanese Paper
Washi paper and the advanced technologies.
A rare combination. An extraordinary fusion
Eco-Drive is a CITIZEN proprietary technology that powers a watch using light the sole energy source. Because all Eco-Drive watches are equipped with a solar cell that sits beneath the dial, CITIZEN has conducted extensive R&D into different materials for dials. Our research finally led us to traditional Japanese washi paper. For hundreds of years, washi paper has been used as a light diffuser in paper sliding doors, floor lanterns and hanging lanterns.
We opted to use the washi paper noted for its long fibres and its combination of great thinness with great durability. At the same time as admitting the light needed to power Eco-Drive through the gaps between the fibres, the paper itself changes appearance depending on the angle at which it catches the light. To maximise the visual impact of the washi paper, we devised a double-layered structure with a transparent top plate, printing on that rather than directly on the paper itself. As well as making the product more robust, this two-layered structure enabled us to introduce a characterful sunray pattern for the whole dial, achieve excellent print quality and apply metal indexes.