Additive Manufacturing Technologies

pp 78-119

Photopolymerization Processes

  • Ian GibsonAffiliated withDepartment of Mechanical & Production Engineering, National University of Singapore
  • , David W. RosenAffiliated withThe George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology
  • , Brent StuckerAffiliated withDepartment of Mechanical & Aerospace Engineering, Utah State University


Photopolymerization processes make use of liquid, radiation curable resins, or photopolymers as their primary materials. Most photopolymers react to radiation in the ultraviolet (UV) range of wavelengths, but some visible light systems are used as well. Upon irradiation, these materials undergo a chemical reaction to become solid. This reaction is called photopolymerization, and is typically complex, involving many chemical participants.

Photopolymers were developed in the late 1960s and soon became widely applied in several commercial areas, most notably the coating and printing industry. Many of the glossy coatings on paper and cardboard, for example, are photopolymers. Additionally, photo-curable resins are used in dentistry, such as for sealing the top surfaces of teeth to fill in deep grooves and prevent cavities. In these applications, coatings are cured by radiation that blankets the resin without the need for patterning either the material or the radiation. This changed with the introduction of stereolithography.