There are CD-R and DVD-R made for archival. MAM-A/Mitsui has tested their Gold reflective layer CD-Rs with their Mitsui dye, to withstand the full spec

There are CD-R and DVD-R made for archival. MAM-A/Mitsui has tested their Gold reflective layer CD-Rs with their Mitsui dye, to withstand the full spectrum of light, same as the sun, for 100 continuous hours without damage. Using data from tests like these, industry standard guidelines predict that MAM Gold CD-R will last greater than 100 years! (In fact, if you extend the data, MAM-A predicts a lifetime of up to 300 years before failing at the Orange Book limit of 220 CPS)