HT-208 NBR primer-free Nitrile rubber coatings for Cylinder Head Gasket
HT209 NBR rubber coatings material for engine steel gasket,silk screen partial coating on gasket surface.
HT-208 NBR primer-free Nitrile rubber coatings for Gasket
Features:
l Thixotropic properties ensure proper screen printing thickness
l High temperature resistant, fuel resistant, resistant to various chemical media
l No primer, adhesion can reach more than level 1
Typical Applications:
Screen printing materials on all metal gaskets for automobiles and motorcycles.
Specifications：
Item | Data | ||||
Before vulcanization | 208A | 208B | 208C | ||
Appearance | Black paste | Black paste | Light yellow liquid | ||
Viscosity | mPa.s | 400～1800 | 400～1800 | ≥100 | |
Mixing ratio | 209A：209B：209C=50：50：20～23 | ||||
After vulcanization | Operating temperature | ℃ | -30~200 | ||
Adhesion | level | 0-1 | |||
Impact resistance | kg/cm | 50 | |||
Flexibility | mm | 1 | |||
Method of use：
1、Before coating, he metal substrate should be deoiled, rusted, sandblasted, passivated or oxidized, washed and dried.
2、The nitrile rubber coatings HT-208A and HT-208B are mixed at a ratio of (50:50), and then 20 to 23% of the curing agent HT-208C is added to stir and filter the screen printing operation. When required, ethyl acetate or butyl acetate may be added in an appropriate amount as a diluent, and the amount must be controlled within 20% of the mixture.
3、The screen-printed material was naturally dried (surface dry) and transferred to an oven for curing. Curing conditions: 165°C×(30-35) min.
Caution:
1、The order of feeding must be strictly followed by the above steps, otherwise it will affect the bonding strength of nitrile rubber and metal.
2、The mixture of curing agent even at a lower temperature, the viscosity of the coating will gradually increase, so it is best to use all the mixture every time.
3、Silk-screened nitrile rubber must be dry completely before it is moved to the oven, otherwise the screen printing tape will foam and deform.