This article examines the flat-glass manufacturing process and explores several decorating methods that you can use to crack into this large market.
By Wim Zoomer
He spent seven years developing the float-glass process, the idea of forming a ribbon of glass by floating the melted sand, soda ash, and limestone at temperatures approaching 3000°F over the surface of melted tin. Today, after the tin bath, the solid ribbon of glass moves roughly 400 ft through the annealing oven, allowing the glass to cool down to approximately 100°F at a steady rate. The annealing process relieves the internal stress of the glass, allowing it to be cleanly cut to the most common jumbo size of 20 x 10.5 ft and processed in a tightly controlled way. The standard size can be adjusted on request and depending on the demand. Nowadays, about 90% of the high-quality flat glass in the world is made according to the float-glass process. Sir Alastair Pilkington was awarded a knighthood in 1970 and died in 1995.
Instead of producing clear float glass, the manufacturer can mix certain chemicals with the standard raw materials prior to melting in order to produce body-tinted glass. The final color of the tinted glass is determined by the additives selected. Tinted glass controls the heat and solar light transmission in buildings. Specific colors are added to reduce the influence of solar radiation in generating heat within buildings. Tinted glass plays an important architectural role, improving the exterior aesthetic appearance of building façades.
Finishing glass in general causes a modification of the glass's surface and its characteristics. Typical finishing techniques are coating, laminating, etching, and sandblasting. These glass-surface-modification techniques produce most required optical or functional characteristics.
Ultra-thin plasma- or CVD-coatings modify the absorption and reflection characteristics of glass by providing clear float glass with a microscopically thin conductive layer. The metal-oxide layers allow light transmission and permit the heat of the sun to pass through the glass into the building.
Laminated glass is manufactured by combining one or more glass panes, using one or more intermediate layers of resilient polyvinyl butyral (PVB), to create high-impact-resistant laminated glass for shop fronts, stair railings, and roof glazing. Acid etching and sandblasting are examples of batch-wise surface treatments. Both techniques create a uniform, matte surface. The surface reflection of the glass approaches that of a perfect diffuser, allowing transmission of light but giving the glass a soft, translucent appearance. Acid-etched glass is a decorative option for doors, shower screens, furniture, and decorative room dividers and separation walls.
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