I have been chasing what I would call the "holy grail" for audiophiles....designing a crystal clear inner sleeve.
Why a clear inner sleeve? Well, if you are using a dual pocket sleeve, do you really want to look at a frosted or paper inner sleeve and hide all of that coloured vinyl coming out nowadays? Also picture discs have had a bad time of it due to most of them shipping with a PVC sleeve and I think everyone understands that PVC shouldn't be used to store records.
For sometime now I have had many discussions, laboratory testing and experimental films in development. Well, I'm happy to say that I have almost finally settled on a film that has all of the properties of HDPE (including anti-static additive) but is crystal clear. The picture shows the visual difference between an HDPE inner sleeve and the clear inner sleeve. This film is proprietary and only available to me.
I plan on offering this inner sleeve in 4 mil thickness to minimize crumpling when sliding the sleeve into the album, in three styles for all record formats. The three styles will be the traditional square open at one end sleeve with a 1/8" lead-in, my proprietary integrated flap and with a tuckable flap.
Clear inner sleeve in a dual pocket tuckable outer sleeve.
Frosted 3 mil inner sleeve on the left, crystal clear 4 mil inner sleeve on the right.