Thanks for your advises and comment. Some additional information about our use hereunder -----Message d'origine----- De : TechNet [mailto:[log in to unmask]] De la part de Bev Christian Envoyé : vendredi 24 février 2012 12:37 À : [log in to unmask] Objet : Re: [TN] Siliporite molecular sieve Cedric, I had to look up was Siliporite was! Molecular Sieves. So the only reason you would put molecular sieves in an oven is to regenerate them. I would PRESUME - to drive off the water they have collected from whatever process you used them in. Molecular sieves can be used for many different things, but you did use the word "drying". Wikipedia says "Temperatures typically used to regenerate water-adsorbed molecular sieves range from 130 °C to 250 °C.[2]" The reference being: "Sudhir Joshi, James R. Fair (November 1988). "Adsorptive drying of toluene". Ind. Eng. Chem. Res. 27 (11): 2078–2085". -> Actually, we use a 120°C oven temperature. I will double if it is hot enough. So I can see a few potential problems here. If the temperature of your oven is anywhere above the low end of the range needed to dry out the molecular sieves, you are going to grow intermetallic up through thin HASL or immersion tin, potentially drive off organics from OSP or immersion silver and/or oxidize any of the last three coatings. On top of that if there are enough molecular sieves, they are heavily laiden with water and there is poor air flow in the oven you are going to be subjecting your boards to a sauna. You have essentially put them in a humidity chamber. Not a good idea. -> The molecular sieves are regenerated daily, the process do not bring a big amount of water and so do not change the humidity rate a lot inside the oven (monitored). -> The remaining question is that if there is a risk of some volatile material that could contaminate PCB Bev RIM -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Cedric ORAIN Sent: Friday, February 24, 2012 5:21 AM To: [log in to unmask] Subject: [TN] Siliporite molecular sieve Hello all, It is said by some "old school" colleagues that drying siliporite in the same oven than pcb could lead to solderability issue ? Is some of you have knowledge about what could happen having siliporite and PCB in the same oven ? Best regards, Cedric ORAIN www.inovelec-groupe.com ______________________________________________________________________ This email has been scanned by the Symantec Email Security.cloud service. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________ ______________________________________________________________________ This email has been scanned by the Symantec Email Security.cloud service. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________ ______________________________________________________________________ This email has been scanned by the Symantec Email Security.cloud service. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________