Subject: Does a solution of car antifreeze and water cool better then water

I am stuck in bed after back surgery and have this cool pack which use ice to 
create a cool soulution to control back function. I obviously have too much 
time on my hands :). I was wonder if i used a mixture of car antifreeze and 
water and froze that. Would that do a better job of creating or maintaining a 
cool( 5 C) mixture. Can you explain why or why not. I do understand the effect 
of crystalliztion on water. I just am not sure if this mixture would store 
more "cool BTUs" then ice from the same freezer. 

Thank you very much.

PS my girlfriend says I am freak, I told her she already had ample proof of 
that.

Re: Does a solution of car antifreeze and water cool better then water