ELASTOSIL® RT 685 A/B
Room Temperature Curing Silicone Rubber (RTV-2)
ELASTOSIL® RT 685 A/B is a free-flowing, additioncuring silicone rubber. After mixing of the components, it yields a ready
to-use product which cures rapidly at high temperatues.
Properties
• solvent-free
• processing viscosity suitable for silk-screen printing
• long-term flexibility over a temperature range from -50 °C to +200 °C
• good resistance to water and mineral oil
• long pot life of ready-to-use mixture
• can be colored with 3 – 5 % Pigment Paste FL
Specific features
• Adhesion promoting primer
• General purpose
• Solvent-based
Technical data
Applications
• Cured-In-Place-Gaskets (Dry Type)
• Fiber Gaskets
• Screen Printing
• Transportation
Application details
ELASTOSIL® RT 685 A/B may be used for applications which require a high and low temperature-resistant flexible coating.
A typical application in the automotive industry is silkscreen printing on selected areas of cylinder head gaskets
Processing
Some fillers may settle during transport and storage. To ensure a uniform
mix, the component A should be stirred thoroughly prior to use.
To prepare ready-to-use mixtures, the components should mixed well.
Small amounts can be mixed by hand or mechanically (e. g. power tool
fitted with mixing blade) for at least 30 seconds.
Colours may be obtained by addition of 3-5 % Pigment Paste FL if
desired. After addition the material has to be mixed carefully.
Note:
Certain substances can inhibit the curing process to a greater or lesser extent. The most notable include:
• Sulphur and sulphur-containing materials (e. g. vulcanizing agents in natural and synthetic rubbers)
• Amines, urethanes and amine-containing materials (e. g. amine cured epoxy resins)
• Unsaturated hydrocarbons (e. g. certain plasticizers)
• Organo-metallic compounds, particularly organo-tin compounds and materials containing such substances (e. g. curing agents and condensation-cured RTV-2 silicone rubbers).
If in doubt carry out preliminary tests to ascertain the compatibility of all materials in contact with the catalysed mix. Liquid product or sticky surfaces indicate cure inhibition. Our technical service will be glad to give you information on how to prevent such problems.
Packaging and storage
Storage
The ‘Best use before end’ date of each batch is shown on the product label.
Storage beyond the date specified on the label does not necessarily mean that the product is no longer usable. In this case
however, the properties required for the intended use must be checked for quality assurance reasons.
Safety notes
Comprehensive instructions are given in the corresponding Material Safety Data Sheets. They are available on request from
WACKER subsidiaries or may be printed via WACKER web site http://www.wacker.com.