7212
Conventional 3D-printers based on vat photopolymerization are curing resins with low viscosity at or slightly above room temperature .
 vat photopolymerization, curing, viscosity, temperature
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: manufacturing standard, machanical property, manufacturing process, material, engineering feature, process parameter, machine or equipment, application, process characterization, enabling technology, biomedical, concept or principle 
Text: {0} 
Answer:
 vat photopolymerization, curing, viscosity, temperature