Rapid Prototyping involved creating a working model of various parts of the system at a very early stage, after a relatively short investigation. The method used in building it is usually quite informal, the most important factor being the speed with which the model is provided.
There are water-and solvent-based -- also called oil-based -- polyurethane varnishes. Water-based polyurethanes are more environmentally friendly and safer to use than solvent-based, but they are not as resistant to wear and tear as solvent-based products.
1 Urethane is the black adhesive which bonds the windshield to the vehicle. 2  In case of an accident, the windshield could pop out if it has not met the safe drive away time period. 3  Every urethane auto glass manufacture has different brands with different safe drive away times.