shelf life

[ratbag]

Hi Folks
Can anyone tell me the shelf life of antifoul?
I have a couple of cans of hemple tiger extra with a date stamp of 03-23
tia

 

[vyv_cox]

Hi Folks
Can anyone tell me the shelf life of antifoul?
I have a couple of cans of hemple tiger extra with a date stamp of 03-23
tia

I bought a 2.5 litre can that was more than 10 years old. Was definitely no worse than a new one and there is every chance it could have been better thanks to a general reduction in toxicity.

 

[thinwater]

I spoke with a number of manufacturers (Petit and International) about this.

Two years is the official line, for un-opened tins. That said, I have used paint up to 10 years old and could not tell the difference in life span. Of course, it needs to be very well sealed, well re-blended, and some solvent addition is generally needed (xylene works well--not mineral spirits).

As for reduction in effectiveness, I just did a panel test for Practical Sailor Mag (30 paints, 3 years), including some old formulas as controls, and no, there really was no overall trend in reduced effectiveness, although of course, some paints are better than others. The best were just as good as ever. They refomulated. The best paints are those that can release the anti-fouling agents evenly over a very long period, not the most toxic. At least that was the case in the Chesapeake.

Unfortunately, Hemple paints were not in the test.

 

[ratbag]

thanks guys, I'm assuming the date stamp is the manufacture date,
I haven't used my boat for a couple of years due to health issues so its time to get out to sea, I think Ill take a chance on the paint

 

[ducked]

Weell, you either assume its OK (perhaps with makeup solvent) or you have to be prepared to dispose of unopened 2-year old paint.

IF you are prepared to consider the second option, you are in a different physical and economic reference frame to me and my opinions on the matter would have no releveence to you.

 

[ChromeDome]

If unopened and stored as per the instructions (cool, dry, and tightly sealed storage, periodic checks for can integrity and consideration of the paint type (solvent- vs. water-based) it is close to unlimited.

"Best before" is a requirement, that also help sales because some are hysterical about it.