Laminated glass speaks to what is laminated glass and why use laminated glass.
It is made by inserting a transparent polyvinyl butyral (PVB) layer between sheets of glass and bonding he three layers together under heat and pressure.
Lamination is the technique of manufacturing a material in multiple layers, so that the composite material achieves improved strength, stability, appearance or other properties from the use of differing materials. A laminate is usually permanently assembled by heat, pressure, welding, or adhesives.
Laminated glass is not as strong as annealed glass of the same thickness,, but when laminated glass breaks, the soft interlayer holds the shards of glass in place rather than allowing them to fall out of the frame of the window. This makes this type of glass useful for skylights and overhead glazing, because it reduces the risk of injury to people below in the case of breakage.
The PVB interlayer may be coloured or patterned to produce a wide range of visual effects in the glass. Because it does not create dangerous loose shards of glass, it also qualifies as a safety glazing.
This glass is a better barrier to the transmission of sound than solid glass. It is used to glaze windows of residences, classrooms, hospital rooms and other rooms that must be kept quiet in the midst of a noisy environment. It is especially effective when installed in two or more layers with airspaces between.
In comparison to solid glass the laminated also reduces the transmission of ultraviolet (UV) radiation, a component of sunlight that contributes significantly to fading and degradation of interior finishes, furnishing and fabrics.
Security glass used for drive in banking windows and other facilities that need to be resistant to burglary, is made of multiple layers of glass and PVB, and is available in a range of thicknesses to stop any desired caliber of bullet.
This glass is also used in blast resistant and windborne debris resistant glazing systems, which are of much use in high wind conditions.
There are different lamination processes, depending on the type of materials to be laminated. The materials used in laminates can be the same or different, depending on the processes and the object to be laminated. An example of the type of laminate using different materials would be the application of a layer of plastic film, the "laminate" on either side of a sheet of glass the laminated subject.
For example, vehicle windshields are commonly made by laminating a tough plastic film between two layers of glass. Plywood is a common example of a laminate using the same material in each layer. Glued and laminated dimensioned timber is used in the construction industry to make wooden beams, Glulam, with sizes larger and stronger than can be obtained from single pieces of wood. Another reason to laminate wooden strips into beams is quality control, as with this method each and every strip can be inspected before it becomes part of a highly stressed component such as an aircraft undercarriage.