View Full Version : Drying agents in linseed oil
labr@
1st February 2016, 06:51 PM
Went to buy some boiled linseed oil for finishing a work bench and found the only choice at that particular outlet was pale boiled with drying agents.
What effect will the drying agents have? Will this make it more like a varnish or change the final feel? Or will it just dry faster?
BobL
1st February 2016, 07:06 PM
Went to buy some boiled linseed oil for finishing a work bench and found the only choice at that particular outlet was pale boiled with drying agents.
What effect will the drying agents have? Will this make it more like a varnish or change the final feel? Or will it just dry faster?
The drying agents in PBLO are metal Naphthenates and usually some white spirit - on one MSDS these represented <4% of the total volume.
The metal Naphthenates are catalysts that increased the rate of polymerization or hardening of the LO,
The net effect is it will dry faster.
These metal naphthenates may interfere with other materials used in finishes but if you are just going to use an oil finish they should be OK.
Big Shed
1st February 2016, 07:07 PM
All "boiled" linseed oil contains drying agents - the term boiled is a carry over from old times when raw linseed oil was heated to partially polymerise it to turn it in to a drying oil.
Raw linseed oil does not contain drying agents and will take a long time to dry or polymerise (ie react with oxygen).
labr@
1st February 2016, 07:38 PM
Thanks Bob and Fred, you've sorted me out.:)