Lowicryl resins are highly cross-linked acrylate-based embedding resins, designed for use over a wide range of embedding conditions. These resins provide low viscosity at low temperatures.
The K4M kit is usable to -35°C and is a polar (hydrophilic) medium, while the HM20 kit can be used down to -70°C and is nonpolar (hydrophobic).
Lowicryl's K11M and HM23 have properties similar to K4M and HM20, but can be used at temperatures 20 degrees lower than others: K11M at -60°C, HM23 at least -80°C. All of these resins are photopolymerized by long wavelength (360nm) ultraviolet light. Since the initiation of the polymerization is largely independent of temperatures, blocks may be polymerized at the same temperatures used for infiltration. The resin may also be chemically polymerized at 60°C.
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