Abstract: The invention relates to an improved method and apparatus for particle blasting utilizing crystalline ice. A theory of impact erosion is presented, as opposed to conventional abrasive techniques, which allows for the development of ice blast conditions to achieve a maximum efficiency for surface cleaning and coating removal applications. By impacting a surface with ice particles which have been treated to bring their temperature near the melting point of ice, erosion is effected by a rupture process caused by the well known reaction-force. It has been found that warming of the ice particles can be realized by simply utilizing unconditioned blast air taken directly form a high pressure compressor.

Abstract: Polymers and articles made therefrom having biocidal surfaces are disclosed wherein the biocidal agent is permanently bonded to the polymer surface. The polymers can be employed to inhibit microbial growth in the adjacent area of the polymer and as disinfectant for fluids such as water. Utility as a contact disinfectant is disclosed.