Metal finishing Q&As since 1989

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Powder paint won't charge properly

2003

Sir,

We are the manufacturer of thermosetting powder(paint). We are facing charging problem in our structure powder.

we have checked for,
1)particle size.
2)silica addition.
3)blending process

There is no problem in all this factors.

Sir for this structure batch we had used GT6084 (EPOXY RESIN) WITH HIGHER VISCOSITY,can the problem arise if viscosity increses/decreses or there is some other reason for this problem.

Wating for reply,

Sachithanand you Pednekar
- India

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Sachithanand,

Poor charging on the powder could be caused due to too much extender being used in the formulation. Too much calcium carbonate or Barium sulphate in a powder will reduce the "chargeability". It is common in structured powder to add too much extender to reduce the cost of the formulation or even to achieve the structure required. If you work to the simple formulating ratio of 2:1:0.5, where 2=Resin, 1=Extender and 0.5=Pigment, you should solve the problem of charging.

Hope this helps,

Drew Devlin
- Lincolnshire
2003

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Dear sir,
We manufacture micronized muscovite mica in 20 microns with lustre .
We would like to know if it can be used as a filler to replace TiO2 in THERMOSETTING POWDERS.
has anyone tried it.

P Salecha
- Pune, Maharashtra, India
2005