Piano Information Blog

Polyester is the most recent material to be used on pianos. It is a product of modern chemical technology that provides the highest degree of beauty and protection available. Polyester is a very stable product and weather changes have no effect on its size. Therefore, applying a stable finish to a constantly changing surface invites trouble. When the wood changes in response to humidity, the polyester can crack or lose adhesion with the wood. Yamaha utilizes a special resin and wood pulp formula to create a sheet of material that provides a stable surface for the polyester application.
This resin sheet is applied directly to the wood and makes the wood under the finish virtually impervious to atmospheric changes. The integrity of the polyester finish is not subjected to changes that could otherwise take place in the wood beneath the finish. Virtually indestructible, polyester protects against sun, heat, spilled liquids and most other substances that tend to destroy a piano’s finish. It is about ten times thicker and up to seven times harder than lacquer. The extra thickness and strength of polyester not only beautifies and protects the wood from scratches, but also seals the wood to protect it from humidity fluctuation.