Bags for CGC books. 2 2

[newshane]

On 11/21/2018 at 9:56 PM, Karl Liebl said:

...mylar just seems more brittle and less shock resistant.

I really don't understand all the comments about Mylar being prone to splitting. I have hundreds of (TRUE) Mylar bags and none of them have ever split. 

However, upon research, it seems like Mylar is susceptible to puncture:

The major benefit of using Mylar in applications is its exceptional strength. In fact, the strength of a sheet of Mylar is often compared with steel sheets of the same thickness. Another pro in using Mylar is its resistance to high temperatures, so this means that is can be used in electrical components that tend to generate high amounts of heat. Also, Mylar is chemically stable, so there is less chance of a dangerous reaction when using other substances along with Mylar.

The main detractor of Mylar is that being very smooth and glossy; it tends to collect dust and other microscopic particles. In applications where light is coming through the Mylar, this debris can be particularly noticeable. And while Mylar has a very high tensile strength, it is susceptible to puncture and becomes a concern when it is used as a wrapper for items with sharp corners. To counter this, manufacturers of Mylar food wrappers often add a layer of polyethylene to reduce the chance of puncture. - quora.com

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The part below is from E. Gerber's website, but it is easily verifiable information:

Resistance to diffusion of gases like oxygen, Carbon Dioxide, Sulfur Dioxide, etc. is 350 times greater than polyethylene.

Permanence. There is no noticeable change in storage-100 years when compared to 2 to 5 years for others.

Resistance to moisture, insect attack, fungus, mold, mildew, acid, oils, grease, and solvents is "excellent" compared to "fair" for others.

Strength and creep resistance is 10 times that of polyethylene, one-third the strength of steel.

Volatile Additions--Mylar® contains no dangerous plasticizers, slip additives, surface coatings, antioxidants, acid-hydrolysis compared to other commonly used plastics.

Below is a link to a more scientific article:

CLICK HERE

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I will always stick with Mylar. TRUE Mylar. 

I encourage people to BE CAREFUL of claims by certain sellers that their goods are genuine Mylar. It should be a crime to engage in this sort of false-advertising, but apparently it's not. 

I am not a Gerber shill, just a regular customer. I benefit in no way, shape, or form by providing this information. Buy the bags you want, but personally I'm willing to go the extra mile. 

[newshane]

I'll just say this, you will NEVER see a rat chew through a Mylar bag. 

[the blob]

1 hour ago, shadroch said:

You've passed on a slabbed book because the exterior, unconnected, outer bag didn't meet your approval? Or bought a book only because it's shiny outer bag made it more attractive? 

I have bought hundreds of raw books only because they were in Mylar, but never passed on a book because it wasn't. I can't imagine a books temporary outer bag influencing my decision.

No, I was writing about raw books. That should be clear. I have never even bought a slab in person. And yes, for raw, some books have popped nicely and I tend to think if they were in a dingy bag I might have passed, as they were "on the fence" books. We're talking about $1-3 box stuff where I didn't want to be bothered taking a book out of a dingy poly to look it over carefully. And the nice mylar is of some value when you're talking about really cheap $1 or less stuff because I figure I may just switch the book with one more deserving of mylar and save myself some money because I don't normally buy mylars.

 

Edited December 18, 2018 by the blob