The use of anti-seize is not recommended as it can not only get onto the firing end of the plug and cause misfires but the main concern is that it acts as a lubricant during installation and can easily cause the p;ug to be over-tightened even if your seeing the correct torque reading on your torque wrench.
The trivalent zinc-chromate coating that is on each NGK spark plug is all that is needed to prevent corrosion and seizure and anti-seize is NOT applied at the factory. Torque also goes a long way in preventing seizure. Be sure to tighten to finger tight plus an additional 1/2 to 2/3 a turn or to 18-21 lb-ft
Brandon Peeler
Technical Support Representative
Aftermarket Division
NGK Spark Plugs (U.S.A.), INC.
46929 Magellan Dr.
Wixom, MI 48393
Bpeeler@ngksparkplugs.com