Characteristics of the product
Laminated glass refers to two or more sheets of glass attached to each other by one or more layers of film. It is a high security type of glass as film layers will prevent pieces of glass to fall over when broken. Even though both of glass are broken, the glass will not fall down. This is because fractures of two broken glass will definitely be dissimilar causing the glass to have less chance of falling out compared to other types of glass.
All types of glass can be transformed into laminated glass, no matter what process of glass production is. Plate glass, sheet glass, float glass, any color or level of thickness of glass, reflective glass, mirror, tempered glass and heat-strengthened glass can all be manufactured into laminated glass. Bringing different kinds of glass to be raw materials for producing laminated glass results in the glass with special properties which may not be able to produced with one sheet of glass.
In general, a sort of film applied in the production of laminated glass is called PVB (Polyvinyl Butyral Film). Film producers have been doing research and developing it constantly; thereby, PVB film has diverse properties and different shades of colors to select from. These also include transparency, translucence, and opaqueness such as transparent film, yellow film, blue film, white film, black film, and frosted film. These films can be combined together to form new colors or different levels of opaqueness depending on imagination.
PVB film is highly resistant to UV radiation which generally can prevent UV radiation more than 95%. Numerous PVB films can prevent 99% of UV radiation, some of them can completely obstruct UV radiation. When used together with glass which is partly UV protective, laminated glass can prevent almost 100% of UV radiation. PVB film is a type of polymer, wherefore it allows laminated glass to reduce transmission of sound waves to certain extent. It is noted that the frequency of spoken sounds level will be decreased more than infrasonic sound from machines.
Regardless of how laminated glass with a PVB film in the middle can decelerate thermal transfer, when film’s temperature rises to a certain point, heat will ultimately be delivered into the room.
Besides PVB film, there is also EN film or EVA film (Ethylene Vinyl Acetate Film). This particular film can attach glass along with other types of materials such as paper, cloth, mulberry paper, and different kinds of plastic films. This film does not absorb humidity, laminated glass produced with this film therefore can be manufactured in a normal clean room without the necessity of humidity control.
Sentry Glass Plus (SGP) is a special film with features of attachment and high pressure resistance; using this film will reduce the thickness of laminated glass. Besides, Sentry Glass Plus (SGP) absorb humidity extremely slow. Laminated glass with SGP therefore can be used in humid or splash areas, however it cannot be applied in the area that SGP film will constantly contact with water.
Using special type of resin is the traditional method to manufacture laminated glass before using PVB film. The procedure still exists at the present as it does not require costly investment, yet it wastes time as it is slow to produce and difficult to control its thickness.
- Laminated glass is a high security glass; attaching an interlayer film with glass will prevent glass from falling apart when broken.
- Laminated glass can retard invasion as glass that are attached to each other will break in different direction, an invader accordingly requires more time to attack the glass.
- Laminated glass can resist UV radiation more than 99%.
- With the same thickness, laminated glass can reduce disturbing noise better than ordinary glass.
- Laminated glass can decelerate thermal transmission into the room.
- A combination of various types of glass can form a glass unit with numerous remarkable properties.
- Compared to ordinary glass with the same thickness, laminated glass can receive less force.
- PVB film has a property in absorbing humidity; hence, the film near humidity areas will be ineffective in terms of attachment to the glass. This causes the separation between the glass and the film.
As laminated glass can combine different types of glass which result in a glass unit with diverse properties, it can be applied into almost every place by selecting suitable glass materials for that place. Notwithstanding that this can lead to a higher price, and in some cases, a glass unit will be much thicker than in general which may necessitate stronger structure to handle the weight. Choosing suitable glass is therefore required a comprehensive perspective consideration such as security, appropriateness, and expense in case of using excessive property glass. With the condition that safety is highly important for that particular place, the use of laminated glass is the most appropriate choice. If you want glass to withstand forces in addition to safety, laminated glass produced from heat-strengthened glass or tempered glass should be applied.
According to the law, buildings that higher than 23 meters, large size buildings (1.The area exceeding 2,000 sq. meter 2.Building height exceeding 15 meters and the area exceeding 1,000 sq. meter but not up to 2,000 sq. meters) and extra-large buildings (the area exceeding 10,000 sq. meters) require laminated glass for exterior wall to prevent glass from falling down if there is glass breakage.
* Remarks: Laminated glass that is produced from other glass materials besides float glass tends to have some limitation. Please enquire further information before placing an order.
Caution in use
- Using float glass as a raw material for laminated glass is important to be carefully used due to the breakage causing from heat accumulation of the interior, especially reflective or Low-e float glass. The areas that different part of glass receive unequal heat are risky areas for glass breakage, e.g., glass inside an aluminium frame and glass that leaves or trees blocking sunlight in some parts. It is significant to be aware that an installment of cupboard beside glass will obstruct heat to release. An installment of curtain awning inserted adjacent to glass could also be a factor of increasing the breakage by heat. In these cases, it is highly recommended to select heat-strengthened glass or tempered glass as a raw material.
- In case of using laminated glass for crime prevention, using tempered glass as a raw material should be avoided, whereas it will break into small pieces. Glass accordingly will be crashed and fallen out of the frame easier than float glass or heat-strengthened glass.
- In case of using laminated glass for a roof, there should be a detection on force resistance as well as deflection of the glass to ensure whether it is suitable or not. The roof that requires a large sheet of glass is necessary to use thicker glass as glass will face higher force resistance and tend to deflect more than a smaller sheet. This means that structure of the glass should be sufficiently strong as well, thereby a coordination among an architect, an engineer, and a glass producer to select a suitable type of laminated glass is imperative.
- In areas that require tempered glass as a raw material yet changing glass is inconvenient or costly, tempered heat soaked glass should be used instead.
- Thermal transmission among glass and films could occur due to an interaction between objects. Using laminated glass to prevent heat from the sun is less effective when compared to insulated glass (two or more glass that separated by dry air or inert gas). However, using laminated glass is superior to an ordinary sheet of glass, especially if heat resistant film is applied.
- Low-E glass has Low-E substance coated on surface which helps to reduce heat radiation; hence, this type of glass can radiate heat less than other glass. Majority of Low-E glass cannot withstand atmosphere as the Low-E substance is sensitive to humidity, yet there are some types of Low-E glass that can use outdoors.
- In case of using Low-E glass as a raw material, it is important to not attach the side coated with Low-E to the film, otherwise a special property of Low-E substance which is reducing heat radiation will not work as Low-E substance requires spaces to radiate. Having Low-E substance attached to the film will forbid it from working; thereby, it is important to attached uncoated side of Low-E glass to the film. If the selected Low-E glass is sensitive to humidity, it is then necessary to use as a raw material for insulated glass (vacuum glass). This is because the side covered with substance will interact with dry air or inert gas inside the insulated glass unit, and accordingly reduce thermal radiation. Notwithstanding the humidity sensitive Low-E laminated glass, Low-E laminated glass that is qualified to interact with atmosphere can be used.
Detection whether the glass is laminated glass or not
It is impossible to distinguish laminated glass from ordinary glass unless looking through the side of glass to verify whether there is an interlayer film or not.