Watch Glasses
Watch Glasses
Watch glasses are shallow, circular, and concave, and may be used as beaker or flask covers, weighing, crystallization, and drying. Watch glasses are available in a variety of sizes and materials compatible with virtually all industrial chemicals and solvents. Some models are non-stick and some can withstand temperatures from cryogenic ranges up to 260°C.
Types of Watch Glasses
Watch glasses are normally made from glass (borosilicate glass or soda lime glass) or from plastics such as autoclavable polypropylene or chemical-resistant PTFE. The plastic versions are often single-use and disposable to prevent sample cross-contamination.
• Glass versions may be constructed using shatter-resistant compositions
• Glass versions often have polished, fused, or ground edges for cut-free, safe handling and durability
• Plastic versions may be used at low temperatures and are also lighter in weight
• All versions are available in a range of diameters, thicknesses, and capacities depending upon the intended application
What are Watch Glasses Used for?
• Holding biological samples or specimens for examination, either with the naked eye or under the microscope
• Demonstrations and displays, particularly in educational or classroom settings
• Observation of chemical processes such as precipitation or crystallization
• Weighing of powders, crystals, or liquids
• Gentle heating and/or evaporation of solids and liquids (borosilicate versions)
• Temporary covers for beakers, cylinders, and other containers to reduce evaporation and minimize ingress of dust and other airborne contamination (the curved surface helps prevent sliding and helps return of condensed liquid to the beaker)
Corning™ PYREX™ Ribbed Watch Glass/Beaker Cover
Ribbed design permits reflux of digestate and escape of excess vapor, thus preventing vapor buildup.
DWK Life Sciences DURAN™ Watch Glass Dish with Fused Rim
Watch Glass Dish with Fused Rim
Fisherbrand™ PTFE Watch Glasses
Inert to all materials except molten alkali metals.
Fisherbrand™ PTFE Watch Glasses
Inert to all materials except molten alkali metals.
United Scientific™ Watch Glass
Watch Glasses featuring polished edges for safe use in the laboratory.
United Scientific™ Watch Glass, Economy
Watch Glasses featuring polished edges for safe use in the laboratory.
MCMASTER CARR SUPPLY COMPANY CLR IMP RES PCARB 6X6X1/2INSHT
NC2180679 CLR IMP RES PCARB 6X6X1/2INSHT
Hampton Research HR3-217/22 mm x 0.22 mm Siliconized Square Cover Slides - 10.0 ounce case (approximately 1,000 slides)
HR3-217/22 mm x 0.22 mm Siliconized Square Cover Slides - 10.0 ounce case (approximately 1,000 slides). Please note items from this supplier are non-returnable.