Swissray International Inc. has received a $12 million investment from international venture capital company 3i Group.

3i, which has an office in Waltham, Mass., joins current Swissray investors Commonwealth Capital Ventures, of Wellesley, Mass., and Audax Group, of Boston.

Swissray plans to use the additional investment to expand customer service as well as R&D to accelerate new product development. Swissray designs, manufactures and markets its direct digital Radiography (ddR) technology.