mysterious "sublimination" plastic

[Kevin Groenke]

I just grabbed what I thought was an .010" thick acetate transparency or mylar sheet to laser a test sample.

This materials reacted in a way that I have never previously witnessed. Rastered and vectored artwork turned into a deep orange color. The edges are crisp and clear and the color is consistent and persistent (I can scratch some it off with a fingernail, but it's pretty tough). The effect on the back side of the material is rather stunning.

This material has been sitting in a random scrap bin for years, I have no idea what it is or where it came from. I do not know if this material is designed/intended to do this or if it is just a circumstantial property of the material.

Is this just a commercial material that I haven't heard of? is it available in other colors.Anybody seen this happen "accidentally" before?

-kg

[Rodne Gold]

Probably polycarbonate or thin lexan?

[Kevin Groenke]

I don't think so Rodney, there was none of the black smoke that we usually see when polycarb inadvertently gets into the laser. The effect is so consistent that it's hard for me to believe that the material isn't designed to do this.

I've never seen this effect other times that polycarb has been cut.

-kg

[Dee Gallo]

Boy I'd love to know what that is! It's a nice change from frost/color fill.

[Richard Rumancik]

Wow, that is a pretty bright orange.

I'd say it is PVC. When you laser PVC, it tends to turn orangish but I would not have expected the intensity that you achieved.

Of course, we all know that you have to be careful with PVC due to acidic and toxic fumes.

If you want to be convinced see this site on marking PVC pipe (scroll down a bit):
http://www.macsa.asia/index.php?tpid=0112

Here's another application - marking PVC IV bags
http://www.synrad.com/newsletter/0303/0303.htm

[Andrea Weissenseel]

I don't think it's mylar. I cut and engrave a lot of mylar (not the clear one though) and it never changes colors. You can easily test if it's PVC or not, look here http://www.sawmillcreek.org/showthread.php?t=114701

Andrea

[Kevin Groenke]

I went to Blick and bought a bunch of clear plastics to try to determine what this stuff is.

Hit it on the 3rd sample, and Richard is the winner.

Grafix CLEAR-LAY plastic film (http://www.grafixplastics.com/clearlay.asp).

Unfortunately this stuff is PVC, so lasering it is producing chlorine gas and hydrochloric acid: no wonder I've had a splitting headache and have been bleeding from multiple orifices since I cut it.

I guess it was too good to be true.

-kg

[Dee Gallo]

What a bummer. Ah well, it was fun to think about while it lasted.

[Robert Walters]

For future reference...

Simple way to test if material contains PVC
http://www.sawmillcreek.org/showpost.php?p=1526588&postcount=2

[Gary Hair]

For future reference...

Simple way to test if material contains PVC
http://www.sawmillcreek.org/showpost.php?p=1526588&postcount=2


but the bleeding orifice and splitting headache will work just as well...