P glycol and BZT

Maine-iac

Member
Joined
Oct 12, 2004
Messages
462
Location
Island Heigh
Format
Med. Format RF
Wayne said:
Is there any reason to choose poly over propy? I can order propylene glycol at the pharmacy for about $10/pint. Does it have a strong smell or other potentially unpleasant qualities I should know about before I order it?

Propylene glycol is sold as "green" or "environmentally friendly" antifreeze in some autoparts stores. I got a gallon for under $12. It works fine in any developer I've tried it with.

Larry
 

Gerald Koch

Member
Joined
Dec 14, 2004
Messages
1,662
Format
Multi Format
The problem with using antifreeze in developers is that it contains other chemicals such as rust inhibitors. One never knows what effect they will have. Even though one brand or batch may not cause problems is no guarantee that the next one will not. I always recommend buying pure propylene glycol. The Chemistry Store sells it for $17.38 plus shipping. Yes it is more expensive than the antifreeze but worth the peace of mind.
 

Ryuji

Member
Joined
Jan 15, 2005
Messages
1,415
Location
Boston, MA
Format
Multi Format
A common cheap corrosion inhibitor is sodium nitrate or something similar. These compounds are readily soluble in water but not so in glycols.

Sure, componds like benzotriazole and its derivatives are also used as anticorrosion agents, and I'm not excluding that possibility...
 

Maine-iac

Member
Joined
Oct 12, 2004
Messages
462
Location
Island Heigh
Format
Med. Format RF

You're probably right. Maybe I just got lucky with the particular brand, but I've experienced no adverse effects from the gallon of antifreeze I got.

Larry
 
Cookies are required to use this site. You must accept them to continue using the site. Learn more…