Materials

Encapsulation bags

Comic Book Bags- There is a debate about rather maylor or polypropylene is the best material. The library of Congress uses maylar to preserve paper with so maylor is is the most expensive of the three options below.

Polyethylene: Ok for short term usage ( a few months to a few years) It prohibits a great amount of light penetration. It also protects the comic from dust and dirt and other foreign elements and is more flexible than polypropylene

Polypropylene : Though better for long term storage than polyethylene this material has some drawbacks. It is rigid and can tear easily at the seems if not handled carefully.

Maylor: Resistance to diffusion of gasses like oxygen-carbon dioxide sulfur dioxide. Has a greater resistance to moisture, insect fungus mold and mildew acid oils and grease. ( called the Cadillac of storage bags)

Bag Thickness

Depending on the comic ( what value one places on it) you can get from 1mil to 4mil thick bags copied form – blog

7″ (aka Current) – I do not like using this width. Frequently I find that a thicker annual or giant size comic just won’t fit, or even some indie comics that have slightly wider trims.

7 1/4″ (sometimes called Standard, sometimes Bronze) – A good overall width for comics from the 1970s onward. In fact, most Marvel Comics from the 1960s that are normal thickness (e.g., not giant-size annuals) fit just fine in these bags.

7 3/8″ (This is Bill Cole’s “standard” width) – Fits most comics from the mid to late 1960s onward. A nice overall width that fits almost any book after the true “Golden Age”, and still able to be fit into a long box or drawer box.

7 3/4″ to 7 5/8″ (Silver/Gold) – Good for the 1950s onward. These present a challenge on storage because they are too wide to fit in a long normal box or drawer box, unless stored sideways.

8″ to 8 1/4″ (Super Golden) – Used for comics from the 1940s to early 1950s.