Microscope slides manufactured by KNITTEL in accordance with the international standard ISO 8037/I, are made from a special improved soda lime float glass in the standard dimensions:
- (26 x 76) mm
- (3“ x 1“) inch
- (25 x 75) mm
and normally in the thickness of about 1 mm.
Specials in different dimensions, thicknesses and glass types are available on request.
For many years, KNITTEL has obtained the special thin floatglass from the world’s leading glass company, exclusively produced for microscope slides using the most economic and modern production-technology for sheet glass today.
Floatglass is chemically a soda-lime glass. Compared to the machine-drawn glass most competitors are using, the Floatglass has superior flatness tolerances which makes it the best choice for all automated equipment. Knittel uses European quality Floatglass for its microscope slides.
For a few applications, e.g. special fluorescence-microscopy (transmission mode), KNITTEL offers also an ultra white (low iron) glass slide (Microcrown). Microcrown is a highly transparent optical crownglass developed for use as optical glasses.
Sand is the most important glass material at the production process. About 50% of the earth’s crust is silicon-dioxide (SiO²-), the main component of sand. Almost all sand-pits are more or less contaminated by, for example, coloured oxides, especially iron oxide. Even a content of 0,14% Fe²O³ limits the usage of this “sand”, so that it cannot be used for sophisticated applications, like manufacturing mirrorglass, due to the fact that at higher glass thicknesses it shows a green colouration. On the other hand, there are sand-pits with an iron-content of 0,1% -0,03% Fe²O³, which are often used for manufacturing special thin glass for rare technical applications, but these are seldom found. Therefore, in many sand-pits additional refining processes are common. Naturally all other raw-materials (e.g. dolomite, feldspar, etc.) for manufacturing special-glass have to have a low iron content, as well.