"Film" on vinyl question

From time to time I receive emails with questions about vinyl and/or the value of a particular record. But, I want to share an interesting question and certainly the source where the gentleman got the best answer:

I have a question regarding record cleaning. I have several 1980's 45's that have been well taken care of for many years, kept in picture sleeves, in plastic and stored in good plastic corrugated cartons. They have not been played and have been stored for years. I noticed this morning that some of the records are still shiny and new looking, while some others are now "cloudy" and dull looking on the vinyl. The vinyl in not shiny anymore... I cannot see my reflection in the runoff groove. They seem to have a film haze on them

Any idea why this is? I can't find any info online about this issue.

Thank you,
Dan
Seekonk, MA

My answer was to first rule out "smoke", and Dan said it is from a non-smoking household. Then I thought it may be from sunlight (the ultraviolet rays) sounds like ultraviolet light has caused the discoloration. But, the record had not been exposed to the sun. So, my next reply was that the ink had somehow "bled" through to the vinyl record. But Dan found the answer at www.vinyltourist.com and sent me the reply they sent him:

Hi Dan...

It might be a transfer from the inner sleeve. Is the
paper sleeve lined with plastic? Some of them are.

If not, it's also possible that in a relatively
unventilated environment, like inside the clear, outer
package in the second photo, a chemical reaction can
occur between the plastic packaging and the records.
Does the material that the "U2 Pac" is made of have a
distinct, plastic-like odor? If so, then it's made out
of polyethylene and not archival. If it's odorless,
then it's polypropylene, chemically inert, and not
harmful.

Is the seal on the "Pac" relatively tight? Do any of
your other records, aside from this set, have this
problem? If yes to the former and no to the latter
(and the plastic smells), then the condition was
probably caused by off-gassing from the plastic
package. With no place for the gas on the inside to
go, it caused a chemical reaction. Unfortunately,
there's no way to reverse this process.

As a collectible, you should save the original "Pac,"
remove the records and all inserts, and store them
separately. You may be able to find replacement 45's
that are unblemished (and missing the original
packaging) for a good price. Keep the plastic in a
separate storage envelope, away from light, since
exposure to light will cause it to become yellow over
time. Don't throw the plastic away, because if you
ever want to resell it, then it's important to have
all of the original pieces.

Hope that helps!

Regards,
Joe

I hope this helps educate us on this discoloration issue and I want to thank Joe at www.vinyltourist.com for his excellent explanation. I sure learned something :)