GLASS

Solar irradiation causes warming environment. To avoid this problem it is possible to install a special glass known as solar control..

ADVANTAGES OF SOLAR CONTROL GLASSES
1. Comfort

• cold environment without air conditioner
• absence of dazzling phenomenon

2. Cutting conditioning spending
3. CO2 emission reduction[/colored_box]

It’s a product with high technological performance realized in order to maintain environment cold and full of light.

Solar control glasses has the property to catch solar light, but by pushing back heat, thanks to invisible layer.

The efficiency of a solar control glass is quantified by g value, that is solar factor. Higher is g value, more is heat contribution, vice versa low is g value, low is heat contribution.

GLASSES AND RAYS OF SUNLIGHT

Solar radiation that arrives on our earth is characterized by ultraviolet rays, infrareds and visible light.

Irradiation that puts a glass is characterized by a part reflected, a part absorbed and a part transmitted. These components determine the reflection factor, absorption factor and transmission factor.

The principal facts to analyze, for determine solar radiation incidence on a glass and for understand glass performances are:

• LT-Light transmission;
• LR-Light reflection (internal/external);
• EA-Energetic absorption (solar energetic flux absorbed by glass that causes heating, expressed in percentage);
• DET-Direct energetic transmission (the quantity of solar irradiation that glass passes expressed in percentage. It represents the fraction of solar energetic flux that is transmitted directly through glass, in which its spectral density changes from 300 to 2150 nanometre);
• G-Solar factor

GREENHOUSE EFFECT

Solar energy, that enters through glasses is absorbed by objects and internal walls and these when they heat, they re-issue a thermal irradiation.
Solar energy that is entered, is trapped within environment that begins to heat. Glasses, even if are transparent, are opaque in comparison to radiations more than 5 μm (micrometre).
Solar energy entered from glass is trapped inside rooms, that begins to heat.
It occurs the greenhouse effect.

FILTERS AND FILTERS

A shutter, roller blind or sunshade are elements that could control solar level, by screening solar rays.

Solar control glasses carry out a filter function, but they have the unique characteristic that allows to not restrict visible area inside house, that is transparency.

Glasses used for windows production, generally would respect several laws about heat insulation, sound insulation, resistance to loading and overladen; they have to pertain to fundamental principles of security according to UNI 7697 regulation.

This regulation expresses principles of glass’s choice that have to be used, inside and outside, in order to guarantee necessary qualifications for people’s safety and thing’s protection.

Security glasses have two functions:

• defend people against casual impact that could cause them hurt;
• defend house life and personal commodities.

There are two security glasses assigned to defend people against hurt: tempered and stratified.

Tempered security glass in case of breakage, it crumbles in little innocuous fragments and so in certain case, it could be considered no hurt glass, and it is classified in Italian regulation into different classes: 1(C)1, 1(C) 2 and 2(C)2 that is the highest.

It is obtained thanks to a heat process, by bringing glass to a temperature of 700° and successively by making an immediate cooling, that is able to create a superficial compression by increasing mechanic and thermal resistance; this treatment makes it more resistant than a normal glass.

Stratified security glass is characterized by two sheets of glass joined by a plastic film.
In case of accidental push, it breaks in fragments and remain linked to plastic films, by avoiding hurts.

It exists a wide range of stratified security glasses, no break-in and no-vandalism glasses that delay breaking and entering and avoid entrance.