I want to make some insulated bags for groceries (like a grocery tote, but insulated to keep frozen stuff frozen longer). What would you recommend to use as insulation? I'd like to be able to keep groceries in my car on hot days for a couple of hours, so I don't think regular batting will work.
thanks!!!

Would insulbrite work?

whatn about insulbrite, the stuff they use for panholders not sure i spelled it right.

I'm not sure. I've never used that stuff before. Is that what they use in the bags you purchase (like the lunch bags)?

Yup, it will keep the cool or heat in or out, depending on which way you put it in. ;-)

Put a "blue ice" pack in the bottom before you go to the store. The Insulbrite will keep the cold in. (It has a metalic layer between white batting with metallic threads.)
If you want something thinner, check the sporting goods store for a "space blanket" that hikers carry for emergencies.

I would use Insulbright, and don't just make an open tote, make the top fold over, zip or close in some fashion or the cold won't stay 'in'.

my thoughts exactly

If you are talking a hot car and a couple of hours you need to put your insulated bags into a cooler that has cold packs in it. Google food safety and talk to anyone who has truly experienced food poisoning. Not worth the risk!

So true about not taking a chance....We use the empty 2 litter coke bottles, fill with water and freeze. Then we use these in the coolers and they keep frozen oh so much longer than the cold packs. Even smaller size water bottles work well, they just don't keep frozen as long.