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Types of Glass & Quality Facts

Types of Glass available through Qorpak

Type I Borosilicate Glass provides excellent protection against chemical attack. Borosilicate glass has a higher softening point for greater heat resistance. It is more resistant to thermal shock and when broken, borosilicate glass tends to crack into large pieces rather than shattering. All of Qorpak's vials, beakers, graduated cylinders, glass media bottles and glass flasks are borosilicate glass.

Type III Soda Lime Glass is chemically inert and recyclable. The surface of the glass is non-porous and smooth which makes it ideal for cleaning processes. Qorpak's bottles and jars are Type III Soda Lime Glass.

Safety Coated Type III Soda Lime Glass can help to prevent lab mishaps. Bottles are slip resistant — which gives technicians improved handling stability. The impact-resistant coating means fewer broken bottles in the lab, or in transit. If a bottle should break, the clear plastisol coating contains the acids, solvents, alcohols, surfactants, esters, ethers, and glass particles long enough to allow proper disposal. Helps ensure compliance with OSHA, D.O.T., and UPS requirements and reduces product liability. Safety Coated Glass is inert and provides complete protection against gas and product permeation.

Water White Glass is chemical resistant and provides excellent clarity. Our microscope slides and cover glass are made from water white glass.

Glass Quality Facts

When glass containers are formed, the surface of the glass is enriched in alkali. The annealing process further enhances this effect. This phenomenon usually of no practical consequence and goes unnoticed. However, in certain circumstances it interferes with further processing of the container.

As glass is exposed to the atmosphere, a complex reaction occurs on the surface between the alkali on the glass and gasses in the air. These reactions are commonly known as weathering. The reaction produces salts, which can absorb water from the air. Weathering salts are composed of a mixture of various hydrates of sodium carbonate and sulfate along with minor amounts of similar calcium salts.

Weathering is a normal condition and such salts are always found on glass surfaces as they are exposed to the atmosphere. The quantity and crystal appearance will vary upon time, humidity, and temperatures of storage. Such salts are easily removed by water rinsing.

All glasses weather, but some are more resistant than others. Borosilicate glasses are the most resistant, followed by soda lime.

The surface treatments used to remove weathering salts or remove the alkali which causes weathering are somewhat limited. Since the salts are water soluble, a simple wipe with a wet cloth or washing prior to decoration or pressure sensitive labeling is effective in most cases.

Heat and humidity cycling or storing glass in a confined space promotes weathering. Keeping the glass under constant low humidity is effective in slowing weathering as it keeps the surface dry and reduces the salt build-up.

Weathering can appear as an oily residue, a general cloudy appearance to a container, or actual crystals which appear on the glass.