Automotive Glass 101: An Introduction and History
Think back to your first car. It may not have been brand new, but it was new to you. You might have picked it for its color, make or model. Chances are you immediately washed it, waxed it and made it showroom clean.
More importantly, you probably shined your windows and windshield to sheer perfection so everyone you knew could see you clearly in your new ride.
The basic functions of auto glass are apparent; structure, protection and design. There’s much more to it, however. Auto glass comes in different types. It also has quite a complex construction. The construction of the glass functions in such a way that it protects occupants from the inside out.
Types of Automotive Glass
All auto glass is made of safety glass. Safety glass is constructed to shatter in the event of incident in order to protect the occupants in the vehicle and protect the integrity of the vehicle’s structure. There are two primary types of safety glass found on an automobile.
The windshield of the vehicle is made with laminated glass. Laminated glass has multiple layers. A layer of vinyl laminate is sealed between two layers of composite glass.
The seal created between these layers makes a bond so strong that the windshield can withstand the 2,000 pound force of an airbag; it can deflect 95 percent of the sun’s ultraviolet rays and absorb the secondary force suffered in an automobile accident.
Laminated glass contributes vastly to the integrity and structure of a vehicle. The glass, together with other safety features and intentional crush zones has rendered vehicles much safer than they were decades ago.
For example, the windshield is significant in reducing the chance of occupant ejection in rollover accidents. It also helps to maintain the vehicle structure and prevent the roof from crushing in on the occupants.
The remaining windows of the vehicle are made of tempered glass. Tempered glass is glass created by the fluctuation of temperature. First the glass is heated then rapidly cooled.
This process not only makes the glass 5 to 10 times stronger than its original state. It also causes the glass to shatter in small, crumbled pieces. These crumbled pieces are dull and much safer than the large shards of glass that come from broken mirrors or other standard glass.
Tempered glass is much safer for the occupants in the vehicle and it withstands the minor bumps experienced in everyday driving. It can even withstand most minor to moderate vehicle impacts. This extra security allows drivers and manufacturers to concentrate on more critical safety features.
How it all started
The automotive glass industry has coming a long way in just the last few decades. When looking back to its origination, we have to venture back to the innovation of French chemist Edouard Benedictus. He discovered the shatter-resistance of glass coated with film when he mistakenly dropped one of his glass flasks.
An assistant of Benedictus had failed to properly clean the flask after it had been used to hold a cellulose nitrate solution. The solution dried leaving a thin layer of plastic inside the flask. When Benedictus dropped it, he noticed the broken glass stayed adhered to the coating, maintaining its original structure. From this discovery, Benedictus went on to invent safety glass and bullet proof glass.
By the 1920’s, laminated glass was implemented into vehicles. It was a clumsy start with weak versions of what is used today. Tempered glass was then introduced in the late 1930’s. It took several decades to perfect what automakers really wanted to do; protect passengers, make more reliable vehicles and increase vehicle sales.
The National Highway Traffic Safety Administration was formed in 1970 as a result of the realization of the dangers that many vehicles were causing to consumers. The NHTSA began monitoring manufacturers, testing products and setting government safety standards. Since its formation, the NHTSA has been vital in the area of vehicle safety and progression.
The NHTSA conducts special crash investigations to review how auto glass responds to such things as different levels of motor vehicle impacts, occupant ejections, and object penetration. In the event that defects are found, the administration implements necessary recalls and ensures manufacturers and dealers contact vehicle owners for immediate correction.
Automotive Glass Continues to Evolve
The auto glass industry remains steadfast in the products that work. We can expect for laminated and tempered glass to remain the primary source of vehicle safety glass for many years to come. However, many considerations are being taken to make those reliable products better.
Generally, laminated glass is only used on the windshield of the vehicle because it takes the brunt of most impacts to include flying objects and debris. Some car manufacturers have attempted to use laminated glass throughout the vehicle instead of using tempered glass. While this sounds like an ideal option, it poses some concerns when taking into account an emergent need to get into or out of the vehicle.
Consider the parent that locks their newborn in the car with the keys. A chilling thought, but it happens. When lockout service just isn’t quick enough, emergency personnel may consider breaking a window. The strength of laminated glass could make this a difficult feat.
Smart glass is an evolving advanced type of safety glass that is being touted with many light and temperature transmission properties. It has already been introduction is some business and residential structures and is currently being tested for automotive use. Manufacturers like Mercedes have already begun using a form of this high tech glass in their sunroof glass.
Smart glass has the ability to tint itself, which is much like the transition lenses that have been used for many years in optical lenses. It can even heat itself, reduce glare and repair itself. Smart Glass is expected to be the optimized future of auto glass with a $3.5 billion dollar affect on the industry.
Auto makers are experimenting with different options to give added security for theft and adding a sleeker look to vehicles while still maintaining its safety for consumers.