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Air bubbles problem

2006

I'm working Plastic dip coating on porous substrate .
but air bubbles are trapped by plastic coater while coating and these bubbles make trouble when substrate dried.

Could you someone tell me if is there any simple method to remove air compressed inside porous substrate before coating?

And contact angle between plastic gel and substrate, can it be active factor in trapping air ?

the_muzi
Altay Tecnical textile - Germany

Are you using a primer?

James Watts
- Navarre, Florida
2006

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First of two simultaneous responses --

I can't understand what you're meaning of using primer.
we use polymer dispersion onto coating flexible substrate by dipping. while dipping,as normal,air are trapped by polymer. we're looking for solution to remove this trapped air.

The_muzi
Altay Tecnical textile - Germany
2006

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Second of two simultaneous responses --

If possible after confering with coating company, heat the items that are to be coated and then coat as they cool. Coating will be sucked in vs. air coming out.
Regards,

Jim Wood
- Concord, California, USA
2007

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2007

Primer was a precoat that is used as a first coat in hot dip plastisol coating. Results are poor if you do not use it.
If you are using a cold vinyl dip (the part is cold) then you should contact tech services of the firm that manufactures your vinyl. They should know the answer with little thought as it will have been asked before. If they can not give a rational answer, strongly consider switching to another source vendor that does have good tech service.
If you want a quality product, you normally have to pay a little bit more for the material, but good service and help when you need it is really worth it. Conside the cost of scrap or rework when you select a vendor and are comparing costs.

James Watts
- Navarre, Florida

Try using some additives such as air release agents.

S Nagendra
- Pune, India
2007