Laminated Glass vs. Toughened Glass:
Key Differences and Applications

In recent years, glass has emerged as one of the most essential materials in construction, automotive, chemical, and or applications. From decorative articles and artefacts centuries ago to lab and kitchen equipment, car windshields and window panels today, glass has evolved and is finding extensive use across domains.

Advancements in technology have enabled specialists to create different types of glass, suitable for a variety of applications – float glass, tinted glass, toughened glass, tempered glass, insulated glass, mirrored glass, wired glass, frosted glass, laminated glass and more. 

Among the most widely used types of glass varieties available are toughened glass and laminated glass. Both are specially treated to offer safety for both domestic and commercial applications. Though the common perception is that they are similar, they offer different characteristics and benefits and are suited for different applications.

Toughened glass and laminated glass

Toughened glass is also known as tempered glass and is created by heating regular glass to a high temperature of 650°C and then cooling it quickly. The process makes it tough and up to 400% -500% more resistant to heat and impact when compared with ordinary glass.

The process of toughening enhances the structural durability and thermal strength of the end product and increases its resilience and capacity to withstand heat. One important aspect to note is that the glass cannot be recut once it is toughened and it has to be cut prior to the process of toughening. Once the glass is specially treated, it breaks into small, blunt pieces under impact which makes them safer than the shards of normal glass.

Toughened glass and laminated glass is manufactured from float glass (annealed glass). Float glass is manufactured by allowing molten glass to cool slowly in a monitored environment and once produced, the clear float glass is cut to size as required and then subjected to further processes like tempering.

Laminated glass has a more complex process. Technically this is similar to the strength of regular glass but the difference is in the design. In the case of laminated glass, two panes of 3mm thick regular glass ensconce a plastic interlayer which holds them together. A tough resin, the PVB plastic interlayer holds the glass planes firmly in place and should the glass shatter, the splinters hold on to the plastic layer and do not scatter like it happens in the case of regular glass.

Internationally, it is prescribed that laminated glass has to be developed to EN ISO 12543 specifications and the transparency of the glass must not be altered during the process of lamination. The resin layers between the glass panes are of different materials. These are:

PVB, EVA & SGP laminated glass

PVB laminated glass is when two glass sheets are sandwiched with PVB (PolyVinyl Butyral) film, a thermoplastic resin film produced by PVB resin with additive plasticizers. The processing and storage of PVB interlayer film is more complicated than EVA as the process requires higher temperature and humidity management. PVB has a range of excellent properties including safety, sound insulation, transparency, and UV resistance. The only weakness is its poor water resistance and the product tends to delaminate in a humid environment over a period of time.

EVA laminated glass created by sandwiching an EVA (Ethylene-Vinyl Acetate copolymer) film between two sheets of glass. EVA has better fluidity which means it can be processed into decorative glass with a range of patterns and designs. It also has a lower melting temperature of around 110°C when compared with PVB and SGP. The other distinct character is that it has commendable water resistance while it has poor UV resistance. The glass tends to turn darker after prolonged exposure to sunlight.

SGP laminated glass has an SGP film (an ion polymer film) sandwiched between the two glass sheets. SGP has twice the load-bearing capacity of PVB at the same thickness and five times the tear strength while it has one-fourth the bending deflection. The SGP interlayer is colourless and transparent and displays good UV resistance. It retains its tint even after prolonged exposure to sunlight compared with PVB.

 

Differences between toughened and laminated glass

Both types of glasses can withstand greater impact and temperature variations, which make them the perfect option for high impact or dynamic environments.

Due to the resin layer in between, laminated glass is thicker than toughened glass and offers better insulation and shock resistance. It is also heavier and more expensive compared with toughened glass and the end user has to decide between toughened glass and laminated glass depending on the application with each type of resin displaying a different property.

Benefits: safety, soundproofing, and UV protection

Laminated glass is widely used in display cabinets to showcase valuables such as expensive jewellery and watch showrooms, exotic pet enclosures, aquariums, glass floors etc. Their security properties are useful in locations such as banks, currency exchange centers, museums and art galleries. It is most commonly used in making windshields of vehicles. 

Toughened glass is widely used in building facades, balconies, skylights, balustrades, roof glazing, partitions, etc. The glass is also extensively used in hotels, airport terminals, recording studios and furniture in table tops, light shades etc.

With an increasing focus on harnessing natural light in buildings, laminated glass is just what architects love as it can absorb up to 99% of the damaging UV rays which means excellent protection for interior surfaces and furniture. The other advantage of laminated glass is acoustic insulation which helps in reducing noise levels ensuring people can have peace and privacy in their work spaces.

Him Imperial – a leading name in glass

Him Imperial Auto Glass Works is one of India’s leading manufacturers of glass and a complete glass solutions company. Him Imperial produces several varieties of glass for various applications. Established in 2008 in Kala Amb, Himachal Pradesh, Him Imperial manufactures to exacting internal standards using the finest raw materials and processes. The company is ISO 9001:2015 certified and our products’ quality standards are approved/verified by ARAI (THE AUTOMOTIVE RESEARCH ASSOCIATION OF INDIA), ICAT (INTERNATIONAL CENTRE OF AUTOMOTIVE TECHNOLOGY), BIS (BUREAU OF INDIA STANDARDS) & IATF (TS). We are a European Union (E+ Marking) certified company.

Our manufacturing facilities incorporate modern machinery and a full-fledged testing lab with sophisticated equipment. We have developed a high level of competence in product development that includes in-house tool design. Today we are a widely recognised automotive and building and construction glass solutions company and produce one of the largest spans of laminated glass (2000 * 3000 mm wide) for front windshields of heavy vehicles.

Since inception, we have focused on forging long term relationships with our customers and are driven by the core values of integrity and commitment to quality. We are proud to have some of the best known names in the industry for customers – leading coach builders, state road transport corporations, heavy engineering equipment manufacturers, reputed builders and developers, prestigious manufacturers of buses, cars and trucks among others, who vouch for Him Imperial laminated safety glass.

To learn more about our offerings in toughened glass, laminated glass and our other products, visit us at www.himimperial.in