Sanoisin että jos pahvi on happovapaa, niin se tarkoittaa että se on sitä kaikilta osin. (Muutenhan siitä erittyisi sitä happoa myös hapottomaan osaan jne.) Kiiltävä pinta lienee siinä enemmän estettisistä syistä. Eli makuasia miten päin haluaa sitä katella. :)
Kyllä ja ei, eli riippuu näemmä täysin valmistajasta: pikaisella googlauksella ainakaan pinnoittamatonta puolta ei kannata käyttää. Kaksipuolisissa "buffered board"(*** pahveissa (E.Gerber tai Bill Cole) ei ole erikseen kiiltävää puolta ja matta-puolta. Toisaalta tämänkin testin tekijä ehdottaa että pahvit kannattaa jättää mieluumin kokonaan pois (paitsi jos Gerber/Cole). Taidanpa nakkailla jatkossa omani metsään, kun ei niistä muutenkaan ole minulle hyötyä.
https://www.cgccomics.com/boards/topic/205695-are-acid-free-backing-boards-truly-acid-free-time-to-ph-test-amp-find-out/Test results:
As was to be expected, of the new boards every single coated backing board (BCW, Ultra-Pro, Miller Hobby and Comic Vision) failed the acid-free test - the coated/shiny side was in every case either pH neutral or pretty close to it, but this was offset by the heavy acidity of the uncoated side.
In contrast, every single buffered board (E Gerber and Bill Cole) passed the acid-free test - on these boards, both sides were pH neutral (or slightly alkaline), and as these boards are buffered throughout (not coated), the entire board can therefore be considered acid-free.
Conclusion:
These boards [siis yhdeltä puolelta pinnoitetut pahvit] are all, at best, "acid-free on one side at time of manufacture" which tells you that at some point some part of this particular board was rendered acid-free, but that the rest of the board will happily contribute to the acidic environment inside your (sealed) comic book bag.
As a matter of fact, it would be safer for your comic book to store them in a bag without a coated backing board.
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(*** Toisaalla netissä selitetään tämä "buffered board"-käsite:
What makes E. Gerber boards better?
Most standard SBS type backer boards - such as BCW, ComiCare, and other leading brands - have the acid-neutralizing alkaline buffer on one side of the board. That's why they're shiny on one side and matte on the other. When used properly those boards are OK for short term use but really should be replaced every 5 years or so as the acid free qualities of the board can change over time.
E. Gerber Premium Backer Boards have the 3% alkaline buffer mixed throughout the board making them retain their acid free, archival state much, much longer.
E. Gerber Boards meet strict US government standards for archival storage.
