Glass is a material with exceptional characteristics, especially when we consider that it is made up of entirely natural substances and that it has multiple uses in dozens of different sectors.
Processing glass is more than just an industrial operation; in many cases, it is a veritable art form, combining design, technology and innovation. The characteristics of glass are known to everyone: transparency, compactness, structural homogeneity and total chemical and biological inertia, as well as countless other properties that make it a material suitable for many uses.
For us at Isoclima, glass is an essential resource for our production. Although we do not produce sheets of float glass directly, we buy them from highly qualified, trusted manufacturers. Our strength is the “transformation” we achieve with these sheets, which allows us to experiment with different, safe, robust glass solutions.
Composition of glass
Before we talk about the main stages of glass processing, it is interesting to understand its composition. There is actually no single chemical composition of glass. Generally speaking, glass is made from 70/74% pure silica, followed by sodium carbonate, calcium oxide, magnesium oxide, aluminium oxide, boron oxide and glass fragments.
Indeed, one of the most interesting elements is the formula, as different formulas influence the mechanical, electrical, chemical, optical and thermal properties of the glass produced.
Various stages of glass processing
Let us turn to the more technical part of this article, which concerns the processing of glass, by which we mean the most common operations under the ISO standard.
- Cutting: as you can easily imagine, this is the first phase that makes all the others possible. The glass arrives in the company in certain predetermined sizes, and once placed in storage it is cut using high-precision machines to achieve the desired shape.
- Shaping: this operation makes use of numerically controlled machines which grind and shape the glass in the most varied and sophisticated sizes.
- Screen printing: with this operation, inherited from typography, a low-temperature melting glass is printed on one or more sides.
Thus, any pattern may be etched into the glass, whether a simple logo or a colourful, decorative design. Screen-printed glass is perfect for both indoor and outdoor use due to its strength, and can be applied on doors, windows, balustrades, furniture and so on.
- HTM, or vitrification. This is done by seamlessly blending a low-temperature melting paste with glass.
- Painting: this can be done by airbrushing or printing, in various colours and finishes. The operation consists in applying a controlled amount of paint to the selected surface. When required, we can supply painted and screen printed glass, achieved using organic paints.
- Chemical strengthening/thermal tempering: these are two different processes with a single purpose, namely to make the glass more resistant to external stress. Thermal tempering uses heat, while chemical strengthening acts on the chemical composition of glass, making it more elastic by replacing sodium ions with potassium ions.
- Curving: this process achieves glass curved to the desired shape. We perform curving in both static and dynamic furnaces. With a static furnace, we place the glass inside the chamber, and the furnace performs the heating, maintenance and cooling cycle all in one place. With a dynamic furnace, the glass enters a heating chamber at an initial temperature, then enters subsequent chambers for curving, cooling and re-baking.
- 5-axis grinding: this phase follows on from the curving process and involves adapting the size of the glass. As grinding may be coarse, polished or with different profiles, it may be customised to suit the customer's requirements. The glass is ground on the final curved shape.
- Lamination: process obtained by means of an autoclave to bind and fuse plastic materials to achieve a single block. We also laminate using polycarbonate.
- Measurement room: this includes an anthropomorphic arm that compares the geometry of the glass with its nominal geometry using mathematical procedures.
- Additional processing: we offer a dual sputtering service, i.e. the metallic deposit of a coating for IR filtering or heating purposes. Assembly, aesthetic, technical and optical testing of the glass base, sealing/gluing of accessories and packaging.