GE Lexan 943A Resin & HP92W Film _ Anti-static solution(s)!

[jcm61]

I need a to locate a spray or coating that can be used on both GE Lexan 943A-116 [use: Inj-molded plastic cover that features an LCD viewing window for an industrial control] & GE HP92W 7mm thick film [use: top {external} material layer of domed membrane keypad]. The product is intended for use in a Class I, hazardous location, indoor or outdoor, where washdown solvents, harsh environmental conditions (e.g., UV light, petroleum based products, salt spray, etc..)are common. It must be a clear, permanent (i.e., abrasion resistant), relatively low cost, anti-static coating. The measured insulation resistance on both the injection-molded Lexan cover & domed membrane Lexan film keypad must not exceed 1 Giga ohm at 23_+/-2 degree C at 50_+/-5% relative humidity.

I have considered choosing a more conductive grade of Lexan (e.g., carbon or steel filled) for the molded plastic cover. However, there appear to be some significant property and molding trade-offs. Specifically, the clarity and impact strength of the Lexan and increased wear on mold/gating. I want to avoid changing the mold, cycle time, etc.., since we are very late into the project.

I have a list of ~50+ anti static coatings sent to me by GE Plastics {Pittsfield, MA} as possible solutions but am overwhelmed by the volume of this information. I need some direction/feedback from people who perhaps may know of a product or process or have had some experience using something that can meet the above criteria.

Thank You,
John.

 

[chaving]

Have you considered vacuum metalising the product? or in-mould painting or evan in-mould films.

These techniques will allow you to maintain the original mechanical properties of your base plastic material.

 

[EricBoughner]

Hi John - If you are still searching for a solution, I think I have what you are looking for. Please let me know. Eric8@andrew.cmu.edu Also, I'd be interested to find out how you solved, if you've already done so.

Thanks,
Eric

 

[patprimmer]

John
I must say that you are a braver man than me if you use Polycarbonate in a hazardous environment when possibly exposed to solvents containing even small amounts of aromatic hydrocarbons
Polycarbonate is really quite sensitive to solvent stress cracking in the presence of many solvents, especially aromatic hydrocarbons.
Compounds containing small quantities of stainless fibre can have very good permanant antistatic properties. Some of these compounds are rated for use in underground mineing.

Contact DSM or LNP for more details