Polyurethane remover?

JBJohnson

unread,

Dec 20, 2002, 12:35:01 AM12/20/02

to

This summer I was spraying some
clear gloss polyurethane finish
onto a project and I must have been a little downwind.
My eyeglasses have overspray dots all over them.
They are plastic lenses (polycarbonate?). I don't
remember if they have a coating of any kind
on them. Is there a
solvent I can use to remove the overspray without
affecting the lenses? Are there any solvents I should
definitely avoid trying? Thanks for any suggestions.
Jeff

Michael Erwerle

unread,

Dec 20, 2002, 11:42:29 AM12/20/02

to

"JBJohnson" <jbj...@yahooNOT.com> wrote in message news:<fTxM9.22946$K5.7431@fe01>...

Hello Jeff,

I am not an Expert in PU coatings or finish´s
but I have sometimes Equal problems with TPU...

to clean metal parts there is an special PU cleaner
on the european market some ester with an high molecular weight..
but you need high temperatures (about 400°F) and this method sucks...

I had successfully cleand some optical parts with hot vinegar
(boiling) and process times of about 8 hours.
this will cause problems with the non optic parts of your glases...

but I Think the best way will be to destroy the PU using an acid.

try vinegar or lemonjuice with ooderate temperatures of let say 100 to
130°F over night. and then cleaning the glasses the normal way...

Michael

Michael Erwerle

unread,

Dec 20, 2002, 3:17:19 PM12/20/02

to

Hello Jeff,

i forgott:

Coffee is one of the worst media for PU...
put your glases in a pott for a day or so...

Michael
I am not a bug I am a undocumented feature

alan

unread,

Dec 20, 2002, 5:39:27 PM12/20/02

to

"JBJohnson" <jbj...@yahooNOT.com> wrote in message
news:fTxM9.22946$K5.7431@fe01...

> PU is the most difficult coating to strip. Anything that attacks it will
go for the plastic lenses too.

alan

William DiMenna

unread,

Dec 20, 2002, 7:17:44 PM12/20/02

to

The poly urethane coating is most likely a crosslinked system. This means
that it is not soluble in ANY solvents. Many solvents will attack
polycarbonate. Your only chance to get the coating off is if the adhesion to
the lens is poor, this is unlikely.
Sometime you have to learn the hard way...with your wallet.
BILL D

"JBJohnson" <jbj...@yahooNOT.com> wrote in message
news:fTxM9.22946$K5.7431@fe01...

JBJohnson

unread,

Dec 21, 2002, 9:13:55 AM12/21/02

to

> The poly urethane coating is most likely a crosslinked system. This means
> that it is not soluble in ANY solvents. Many solvents will attack

> They are plastic lenses (polycarbonate?). I don't

> > solvent I can use to remove the overspray without

Thanks for the inputs. I had some partial success with a
warm vinegar soak (no visible effect) followed by
an ice water ultrasonic bath (bigger dots gone).
This polymer newsgroup has some interesting stuff
in it. I will be looking in regularly.
Jeff

JBJohnson

unread,

Dec 27, 2002, 10:15:30 AM12/27/02

to

> The poly urethane coating is most likely a crosslinked system. This means
> > that it is not soluble in ANY solvents. Many solvents will attack
> > They are plastic lenses (polycarbonate?). I don't
> > > solvent I can use to remove the overspray without
>
> Thanks for the inputs. I had some partial success with a
> warm vinegar soak (no visible effect) followed by
> an ice water ultrasonic bath (bigger dots gone).
>

At the suggestion of someone who paints upon
plastics, I soaked the glasses overnite in isopropyl
alcohol (50% is what I found at the store) and
next morning they cleaned up like magic. Guess it
loosened up the attachment just enuf.
Thanks!
Jeff

motherof...@gmail.com

unread,

Apr 26, 2020, 9:32:30 AM4/26/20

to

I splattered my plastic lens glasses with polyurethane varnish and a couple of days later soaked them overnight in regular over the counter undiluted isopropyl alcohol (70%) and they cleaned off beautifully the next morning. Thank you so much!