Rudolf Weinberger Holding, the parent company of Austrian roll foundry Eisenwerk Sulzau-Werfen R. & E. Weinberger (ESW), has acquired a 100 percent stake in Polish manufacturer DONAKO from Central and Eastern Europe-focused private equity firm Innova Capital and Germany-based investment company Zeleznik Industrie Consulting. DONAKO produces high precision laminates and tools for electric generators and large motors. Financial details of the transaction were not disclosed.