Plastic Color Fading Outdoors

[stony99]

Hello,

Wonder if any of you has an idea on how this could be resolved. We produced color for Polyrpopylene Chairs that were injection molded for outdoor use.

The formula has orange and yellow colorants, but the orange is fading within 2 months and the color is changing.The yellow pigments are very stable and will last for 3 years outdoors but the orange fades.

How can something like this be re-solved?
John

 

[patprimmer]

Choose light fast colours.

Use UV stabilisers to prevent surface degradation of the polymer.

Regards
Pat
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[stony99]

Pat,

Thanks for the response. We used .5% UV additive and that is protecting the polymer, but one of the pigments is fading quickly.

So the color is changing from an orange shade yellow to a greenish shade of yellow.

The yellow pigments that were used are very stable and resist fading. Unfortunately, we did not know that the orange pigment would fade so quickly outdoors.

The chairs are installed outdoors and the change in color is noticable.

Not sure if any one has ideas on how something like this could be resolved.

Thank you for any thoughts.

John

 

[patprimmer]

It cannot be resolved in existing mouldings.

Discussions with your colour supplier should be frank and to the point about your existing problem and your future expectations. It is up to them to formulte the colour.

Regards
Pat
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[Pud]

Oh, those were the days - when cadmium based pigments were available!

As Pat wrote, I would suggest you talk to your colour supplier and tell them what you need. Iirc, these days reds are tricky (expensive) to get good UV resistance.

H

http://www.tynevalleyplastics.co.uk

 

[stony99]

Thanks H & Pat,

It was my company's fault since we should have known not to use this particular Orange pigment for an outdoor application.

What would we have to do, arrange to have the 10,000 chairs un-installed, and then supply new resin re-matched with a new Orange that won't fade? The only good thing is that they Yellow pigments used in this will easily last 3-5 years outdoors. So once the orange fades out, the color will remain stable. Its just that the difference when the orange fades is very noticable.

Any ideas or thoughts are appreciated.

Thank you,
JP

 

[MacGyverS2000]

Stick them all out in your parking lot for a few months until they fade to a stable color, then sell them?

Dan - Owner

http://www.Hi-TecDesigns.com