SPI Supplies Formvar Coated Nylon Grids, Carbon Coated pk25
Nylon grids, 180 mesh
We offer here carbon filmed Nylon grids, actually we are starting out with our carbon coated grids, and picking up thin films or carbon or lacey carbon,etc. just as we do on other grids. These Nylon grids, available only in 180mesh, are offered for those not able to bring beryllium grids into their laboratory. These grids should not be considered "better" or even equivalent to beryllium grids, they certainly are not, the main reason being that unlike beryllium, they are very high in Bremsstrahlung radiation. But they do work and many researchers use them regularly with confidence.
Note: The Nylon monofilament fiber from which the Nylon grids are constructed does contain a low level of titanium dioxide, so users can expect to see some low intensity X-ray lines from Ti.
Also, the Nylon grids are recommended for use at temperatures over 200° C.
An uncoated Nylon grid would be unacceptably non-conductive, therefore, SPI vacuum evaporates a layer of carbon to impart surface conductivity to the grid's surface.
Batch inspection of all coated grids:
Representative samples from each lot are inspected in our own in-house TEM and any batches that do not "pass" are summarily rejected and not sent to customers. Nothing can be more frustrating than to be all geared up to do an expensive experiment (for example, with live animals), only to find out at the last minute that your coated grids are no good and can't be used! We won't say "never", but it is highly unlikely that anyone will receive from SPI Supplies "bad" grids. Our coated grids are produced in-house and we maintain tight control over the coating operation. If you have had problems with coated grids from other sources, find out if they have their own in- house TEM also, or are they letting their customers do their QC for them.