This provides an in-depth analysis of the product development process for "Sanuki Udon Bath Salts," a unique bath soak designed to make the user feel like a noodle in a bowl of udon. It focuses on how this unusual product, which intentionally lacks traditional therapeutic benefits, successfully captured public interest by strictly adhering to the five stages of Design Thinking.

This framework includes 1) Empathizing with user needs, 2) Defining the core problem as a lack of "experience value," 3) Ideating the concept of "becoming an udon," 4) Prototyping the product accurately with a manufacturer, and 5) Testing/Validating the product through consumer feedback to guide subsequent iterations.

It uses this successful case study from Kagawa Prefecture to illustrate the practical application and cyclical nature of Design Thinking in creating disruptive market products.