When manufacturing silicone-based additives, the current state of technology involves the retention of certain cyclic siloxanes (D4, D5, D6) in the end product.
A re-evaluation of the hazard potential of these substances at EU level dated June 27, 2018 means that some silicone additives now require additional labeling.
The labeling requirements are to be found in Chapter 15 of the EU Safety Data Sheet, which includes details regarding content of Substances of Very High Concern (SVHC). An SVHC warning notice is obligatory if the cyclic siloxane content is 0.1% or greater.
This not only affects accompanying documentation, but it can also entail stricter occupational health and safety requirements wherever such substances are used in paints and coatings, plastics, printing inks or adhesives, and in the various end uses.
Up to June 26, 2018
Since June 27, 2018
PBT: Persistent, bioaccumulative and toxic; vPvB: Very persistent and very bioaccumulative; SVHC: Substance of very high concern; CMR: Cancerogenic, mutagenic and reprotoxic
It is important to note that the permissible threshold of 0.1% applies to each single component and not to the total of all components:
D4 < 0.1%
D5 < 0.1% ⇒ no SVHC labeling
D6 < 0.1%
In order to facilitate the safe use of the silicone additives affected, BYK has purified established standard additives, and variants with low cyclic siloxanes content are now available.
At an additional stage of production, these additives undergo a purification process in which BYK utilizes its own process expertise, such as is also applied in the manufacturing of VOC-free defoamers.
By way of example, the chart below compares the standard additive BYK-306 with its purified alternative BYK-3761 in a 2-pack acrylate clear coat for general industrial coating applications. The result: The surface tension and surface slip are identical; the removal of the cyclic siloxanes has no effect on the product properties.
Standard additives with a cyclic siloxanescontent of 0.1% or greater | Product group | Alternatives with a cyclic siloxanes content of < 0.1% |
|---|---|---|
Defoamer | ||
Defoamer | ||
Surface additive | ||
Surface additive | ||
Surface additive | ||
Surface additive | ||
Surface additive | ||
Surface additive | ||
Surface additive | ||
Surface additive | ||
Surface additive | ||
Surface additive | ||
Surface additive | ||
Surface additive |
Should you wish to have further information on BYK silicone additives with low cyclic siloxanes content, please do not hesitate to talk to your local BYK partner or contact us directly using the contact form.
