The hinges on our Fujitsu laptop screen appear to be 'all' plastic and they
get very 'difficult to move' making the screen difficult to fold up and
down.

We have have tried 'WD-40', but that seems effective for only a very short
time.

We are afraid to use ordinary oil as we thought it might effect the plastic.
We were thinking of using olive oil, but somebody has told us that olive oil
'degrades' and goes sticky, over time.

We have got some Camellia oil that was given to us, and it's made from
Camellias and it comes from Japan and is suppose not to 'degrade'. Still
it's an unknown quantity to us.

Does anyone know what would be a suitable and safe lubricant in this case?
Since we dont want to cause any problems with the plastic on this lap top.
Grateful for any suggestions, thanks.