ELASTOSIL® TC 3807 A/B

RTV-2 Thermally Conductive Encapsulant
ELASTOSIL® TC 3807 A/B is a pourable, 1:1 two-component thermally conductive silicone rubber encapsulant
that vulcanizes at room temperature and accelerates on heat.

Properties
• Two-part system, 1:1 mixing ratio
• Easy to mix and use
• Room temperature curing but accelerates on heat
• Excellent durability

Specific features
• Low viscosity
• Good flowability for fast processing and short cycle times
• Easy deairing to avoid pin holes
• High Shore A hardness (approx. 65)
• Good thermal conductivity (1.0 W/mK)
• Flame retardant, UL 94 V-0 certified
• RoHS certified
• No post curing required
• Excellent reliability over a wide range of temperature
• Aids heat dissipation

Technical data
General Characteristics

Application details
ELASTOSIL® TC 3807 A/B thermally conductive encapsulant is suitable as a potting material for:
• LED drivers
• Power modules
• Adaptors
• Inverters
• Transformers
• Ballasts
• Sensors
• Electronic control units

Processing

Important
Only A & B components with the same batch number may be processed together!

• Application methods
Manual or automated needle dispense

• Mixing and deairing
The product is supplied for 1:1 mix ratio. Prior to use carefully mix the individual components as both of part A & B can
have filler settlement in the bottom. Mixing of individual components has to be carried out till all the settled fillers mixed up
uniformly.

Component A of ELASTOSIL® TC 3807 A/B contains platinum catalyst. Component B the crosslinker hydrogen. Even
traces of platinum catalyst may cause gelling of the component containing the crosslinker. Therefore tools (spatula, stirrers
etc) used for handling the platinum containing component or the catalyzed compound must not come into contact with this
component.

The two components should be thoroughly mixed at a 1 : 1 ratio by weight. To eliminate avoid pin holes in the cured
rubber, the A/B mix can be deaerated by mechanical shaker. For processing ELASTOSIL® TC 3807 A/B in industrial scale,
the use of automatic mixing and dispensing equipment is recommended.

• Surface preparation
In applications requiring adhesion, priming will be required for many of the silicone encapsulants. For best results, the
primer should be applied in a very thin, uniform coating and then wiped off after application. After application, it should be
thoroughly cured prior to application of the silicone elastomer. Additional instructions for primer usage are available in the
information sheets specific to the individual primers.

• Curing
Thoroughly mixed ELASTOSIL® TC 3807 AB may be poured/dispensed directly into the container in which it is to be cured.
Care should be taken to minimize air entrapment. When practical, pouring/dispensing should be done under vacuum,
particularly if the component being potted or encapsulated has many small voids. If this technique cannot be used, the unit
should be evacuated after the silicone encapsulant has been poured/dispensed.

ELASTOSIL® TC 3807 AB, the silicone encapsulants may be either room temperature (25 °C/77 °F) or heat cured. Room
temperature cure encapsulants may also be heat accelerated for faster cure.

The reactivity of ELASTOSIL® TC 3807 AB can be adjusted within wide limits by adding Pt catalyst or inhibitor to suit the
processing requirements of the particular applications. Catalyst increases the reactivity i.e. pot life and curing time are
reduced. Inhibitor is a pot life extender and prolongs pot life and curing time.

• Cleaning
If removal of uncured silicone rubber from machines or dispensing equipment is necessary, white spirit or similar non-polar
solvents are recommended. However, cleaning ideally should take place before the rubber is fully vulcanized. Cured
silicone rubber can be removed by mechanical means, preferably in combination with a swelling agent (solvent).

• Notes
Examples of inhibiting contaminants are sulfur containing materials, plasticizers, urethanes, amine containing materials
and organometallic compounds – especially organotin compounds. If a substrate’s ability to inhibit cure is unknown, a
small-scale test should be run to determine compatibility.

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.
• Packing
Available pack sizes for ELASTOSIL® TC 3807 A/B is as follow:
EL TC 3807 A is available in 25 Kg DRUM PE & 1 Kg TIN ST
EL TC 3807 B is available in 25 Kg DRUM PE & 1 Kg TIN ST

Safety notes
Components A and B of the addition-curing grade ELASTOSIL® TC 3807 A/B contain only constituents that over many
years have proved to be neither toxic nor aggressive. Special handling precautions are therefore not required, i.e., only the
general industrial hygiene regulations apply.
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.