Piano Black in acrylic?

[cpretty]

Hi all,

We have been contacted by a client with the request to manufacture a moulded part in piano black (like every product at the moment).

I remembered the discussions in

http://www.eng-tips.com/viewthread.cfm?qid=243108&page=1

so have been looking over those.

The customer is already using PMMA panels in some locations on their product, so I was wondering about acheiving the same effect in acrylic. I assume the same ideas of transparency to gain depth of colour will hold.

The other reason for using acrylic is its supposedly better scratch and temperature resistance. This unit is around boiling water, so the clouding issues with MABS may also be a problem.

Does any one have any experience that could sway the decision between MABS and PMMA given the above issues?

Cheers,
Craig

Craig Pretty
Tru-Design Plastics

 

[Demon3]

PMMA is perfect for achieving a piano black effect because it is transparent (well remembered by the way).

MABS clouds because it contains surfactant left over from making the impact modifier in it (that is made by emulsion polymerization) and the surfactant draws in the water resulting in clouding.

For neat, non impact modified PMMA, the clouding will therefore not be an issue. Go right ahead!

The very best piano black should be that achieved using dye rather than pigment. Dyes are soluble whereas pigments are insoluble particles. Dyes allow the light to penetrate further, thus enhancing that piano black depth effect. If you are worried about the dye leaching out then try to find polymeric (non-diffusing) dyes. For PP I know that Milliken makes polymeric dyes. Perhaps they do for PMMA too.

Chris DeArmitt PhD FRSC CChem

http://www.phantomplastics.com

Consultant to the plastics industry