We use high temperature paper (170F, 20% dark at 6mJ/mm²). It will not turn dark left many days in a truck dashboard in the summer in Texas. I once found a stac

We use high temperature paper (170F, 20% dark at 6mJ/mm²). It will not turn dark left many days in a truck dashboard in the summer in Texas. I once found a stack of 7 year old receipts and they were completely readable.