Types Of Auto Windshield Adhesives

Windshields are held in their place firmly with the help of adhesive materials that are mainly put between the frame and laminated glass. It is crucial to use the best quality of adhesives that can withstand extreme temperatures and maintain elasticity. The main feature of any adhesive is the strength with which it holds the windshield in a crash, keeping the occupants safe from any glass damage. There are several types of windshield adhesives and sealants available in the market, namely: Silicone, Polyurethane, Modified Silicone, Butyl, and Acrylic. The choice of adhesives and sealants depends on the size of the vehicle (car, bus, construction or agricultural machinery, etc.) and should be made by a professional auto glass expert.

The purpose of an adhesive is to bind two different bodies together while the aim of a sealant, on the other hand, is to block the entry of water, and it is very important to differentiate between these two. In the beginning, sealants like silicone and other variants of it were used for the windshields along with Acrylic. As technology progressed, improved adhesives like Polyurethane (commonly known as Urethane) started replacing other traditional ones. Let us briefly look at salient features of different types of materials used during windshield installations :

Silicone expands in the heat and contracts in the cold, so it can only be used as a sealant to repair leaks in the windshields. It is much cheaper than polyurethane adhesive, but it cannot be used as an adhesive in windshields, as its properties are not suitable for that purpose.

Butyl tape is sometimes employed as a cost-effective alternative adhesive for the windshields, but this needs to be kept in mind that Butyl is an effective sealant and not an ideal adhesive. It has excellent resistance to moisture, but if used as an adhesive while installing a windshield, it won’t form a hard bond with the glass, thus compromising safety.

Polyurethane is the most abundantly used adhesive in the auto glass industry for installing windshields because it is 90 times stronger than any silicon material. It is the only approved adhesive material for windshields, has better elongation, and is not affected by extreme temperature changes. It becomes hard instantly as it is applied and forms a strong bond between the frame and the windshield.

Silane /Silyl Modified Polymers (SMPs)
These are the latest addition to the auto glass adhesives scene, and the main advantage of using them is that no primer is required, therefore reducing the cost and time of application. They have mighty strength and flexibility with all qualities of silicone, Butyl, and Urethane combined in one.

Any professional and sincere auto glass replacement expert would never compromise on the quality of adhesive while installing or repairing your windshield. Still, some workshops try to save some dollars by using silicone or Butyl instead of Urethane or any other approved adhesives. Therefore, it is important to ask or notice the type of adhesives an expert is using, as this is most crucial for the safety, integrity, and long life of your windshield.

Lawrence Tomlinson @ www.alpharettaautoglass.com