cgc-mylars on ebay. False Advertising. NOT Mylar **Updated with sample test**

[Tony S]

I too have bought a few packs of these bags from cgc-mylars. Forget about the text of the listing; how about changing their name??

 

Really glad to have stumbled on this thread & thanks to the OP. For those of you recommending eGerber products, isn't it a complete waste of money to protect CGC slabs with real Mylar? cgc-"mylar"'s bags seem like the perfect product (clearer than poly, cheaper than Mylar), albeit at the wrong price.

 

I don't replace CGC's supplied polyethylene bags for better protection. I do it because CGC's bags are just plain nappy looking. They sag, tear, scuff up and fit poorly. Really, it's the only "cheap" looking part of CGC's product and it has always suprised me they don't use something nicer looking.

 

When I'm feeling cheap, I use a standard polypropylene magazine bag, which has much greater clarity, fits better and doesn't tear so easily.

 

But mylar just looks and feels the best.

[Arkham]

I also use Mylar. 914's. M2.

 

I live in a tropical climate where humidity and mold are a constant issue. So, for me it's worth the slightly extra coin to go Mylar... and as Tony says, nothing beats the look and feel.

[Tony S]

I also use Mylar. 914's. M2.

 

I live in a tropical climate where humidity and mold are a constant issue. So, for me it's worth the slightly extra coin to go Mylar... and as Tony says, nothing beats the look and feel.

 

I wanna live in a tropical climate. Sunshine Coast, Australia. Sounds wonderul

[comeaux]

Are CGC slabs 100% airtight?

 

I was under the impression that CGC slabs are not 100% airtight and that they do breathe to allow airflow through the slab, if this is the case then it seems that Mylar would be the best for archival preservation of CGC graded books.

 

If CGC slabs are 100% airtight then I guess Mylar is really not needed but as others have said, I like the look of Mylar for the price.

 

[joecgcmaniac]

Are CGC slabs 100% airtight?

 

I was under the impression that CGC slabs are not 100% airtight and that they do breathe to allow airflow through the slab, if this is the case then it seems that Mylar would be the best for archival preservation of CGC graded books.

 

If CGC slabs are 100% airtight then I guess Mylar is really not needed but as others have said, I like the look of Mylar for the price.

 

No, the slabs are not 100% airtight.

[comeaux]

Are CGC slabs 100% airtight?

 

I was under the impression that CGC slabs are not 100% airtight and that they do breathe to allow airflow through the slab, if this is the case then it seems that Mylar would be the best for archival preservation of CGC graded books.

 

If CGC slabs are 100% airtight then I guess Mylar is really not needed but as others have said, I like the look of Mylar for the price.

 

No, the slabs are not 100% airtight.

 

Thanks Joe and since that’s the case in which the slabs are not 100% airtight then it seems that using Mylar bags for CGC slabs is a good way to go for long term protection.

[mschmidt]

Are CGC slabs 100% airtight?

 

I was under the impression that CGC slabs are not 100% airtight and that they do breathe to allow airflow through the slab, if this is the case then it seems that Mylar would be the best for archival preservation of CGC graded books.

 

If CGC slabs are 100% airtight then I guess Mylar is really not needed but as others have said, I like the look of Mylar for the price.

 

No, the slabs are not 100% airtight.

 

Thanks Joe and since that’s the case in which the slabs are not 100% airtight then it seems that using Mylar bags for CGC slabs is a good way to go for long term protection.

 

No, in general you don't want to store paper in a completely airtight environment.

[comeaux]

Yes that is what I understand and was alluding to the fact that since the CGC slabs are not 100% airtight then it a good practice to use Mylar instead of polypropylene bags for storage.

 

I'm not an expert in this area but it seems that using polypropylene or any other type of bag other than Mylar can be detrimental in the long term storage of comics ... correct ?

 

[newshane]

Yes that is what I understand and was alluding to the fact that since the CGC slabs are not 100% airtight then it a good practice to use Mylar instead of polypropylene bags for storage.

 

I'm not an expert in this area but it seems that using polypropylene or any other type of bag other than Mylar can be detrimental in the long term storage of comics ... correct ?

 

I've seen modern comics sit in polybags for over 20 years. They come back 9.8 with white pages.

 

 

[Jaws1965]

Gotcha on all, guys, thanks for the info. I'm relieved somewhat, but like many of you, the dishonest sales really stick in my craw, if for no other reason than learning the degree of massive profit this guy made on all those dishonest sales.

 

I'm not sure I'm going to tilt at this windmill as I'm super busy at work, but I am tempted if only because I now know how cheap I COULD have bought the BOPP bags -- when not going thru an unscrupulous middle man misrepresenting them as mylars.

 

I'll let you know if I decide to do something...

[Heronext]

Are CGC slabs 100% airtight?

 

I was under the impression that CGC slabs are not 100% airtight and that they do breathe to allow airflow through the slab, if this is the case then it seems that Mylar would be the best for archival preservation of CGC graded books.

 

If CGC slabs are 100% airtight then I guess Mylar is really not needed but as others have said, I like the look of Mylar for the price.

 

No, the slabs are not 100% airtight.

 

I would guess (someone here might be able to confirm) that the plastic outer hard case ("the slab") is of poorer archival quality than any mylar bag one might place it in...

 

 

[Arkham]

I wanna live in a tropical climate. Sunshine Coast, Australia. Sounds wonderul

 

It's a tough gig mate, but someone has to do it!

[Tony S]

Are CGC slabs 100% airtight?

 

I was under the impression that CGC slabs are not 100% airtight and that they do breathe to allow airflow through the slab, if this is the case then it seems that Mylar would be the best for archival preservation of CGC graded books.

 

If CGC slabs are 100% airtight then I guess Mylar is really not needed but as others have said, I like the look of Mylar for the price.

 

No, the slabs are not 100% airtight.

 

I would guess (someone here might be able to confirm) that the plastic outer hard case ("the slab") is of poorer archival quality than any mylar bag one might place it in...

 

 

The inner holder CGC says is Barex. A good choice. Not as archival as Mylar - but it is used/approved for packaging food and medicince. More important for CGC is that it's easier to heat seal (300 degrees) than mylar (almost 500 degrees) Temps are Fahrenheit which us Americans still cling too...

 

CGC has never said what the outer holder is. I believe it is some type of acylic. I also suspect that the reason CGC doesn't say what they use is because there are several choices that would look much the same and work just as well or even better (polycarbonate for instance). They probably want to be able to use whatever is least expensive.

 

Technically - and you'll find lots of people saying so here on the boards - a quality buffered backing board and a mylar bag are more archival than CGC's encapsulation. CGC themselves suggests reholdering books every 7-10 years, where mylar is so inert that you are protected for 100 years.

 

But - the hard outer shell of the CGC holder provides much greater protection to books that are handled. So if you want to show your books to friends, encapsulation is great. And of course the primary reason for slabbing more expensive books is to establish a grade that is much less likely to be debated when/if you go to sell.

 

[comeaux]

Are CGC slabs 100% airtight?

 

I was under the impression that CGC slabs are not 100% airtight and that they do breathe to allow airflow through the slab, if this is the case then it seems that Mylar would be the best for archival preservation of CGC graded books.

 

If CGC slabs are 100% airtight then I guess Mylar is really not needed but as others have said, I like the look of Mylar for the price.

 

No, the slabs are not 100% airtight.

 

I would guess (someone here might be able to confirm) that the plastic outer hard case ("the slab") is of poorer archival quality than any mylar bag one might place it in...

 

 

The inner holder CGC says is Barex. A good choice. Not as archival as Mylar - but it is used/approved for packaging food and medicince. More important for CGC is that it's easier to heat seal (300 degrees) than mylar (almost 500 degrees) Temps are Fahrenheit which us Americans still cling too...

 

CGC has never said what the outer holder is. I believe it is some type of acylic. I also suspect that the reason CGC doesn't say what they use is because there are several choices that would look much the same and work just as well or even better (polycarbonate for instance). They probably want to be able to use whatever is least expensive.

 

Technically - and you'll find lots of people saying so here on the boards - a quality buffered backing board and a mylar bag are more archival than CGC's encapsulation. CGC themselves suggests reholdering books every 7-10 years, where mylar is so inert that you are protected for 100 years.

 

But - the hard outer shell of the CGC holder provides much greater protection to books that are handled. So if you want to show your books to friends, encapsulation is great. And of course the primary reason for slabbing more expensive books is to establish a grade that is much less likely to be debated when/if you go to sell.

 

Thanks ! (thumbs u

[InvstmntComcSuply]

Just wanted to update this thread.

 

I received some bags from the suspected manufacturer and can confirm that they are identical to the bag cgc-mylars is marketing as Mylar. However, these bags are made of BOPP polypropylene.

 

Just to be clear, I think the bags are great. They are far clearer than standard polypro bags and at the $13.50 per hundred price direct from the manufacturer, they are also a great deal. As opposed to the $47 per hundred that cgc-mylars is charging.

 

However, cgc-mylars continues to FALSELY advertise these bags as Mylar in all of their auctions. Apparently ebay will do nothing about it without multiple Reported Item notifications, negative feedback or chargebacks on the seller.

 

Any other suggestions?

[newshane]

I don't know but count me in.

 

I am !

[AlexanderM]

What is the difference between Mylar and Polypropylene bags? Both are acid-free.

 

(in the context of preserving raw comics)

[youmechooz]

What is the difference between Mylar and Polypropylene bags? Both are acid-free.

 

(in the context of preserving raw comics)

I do know that if you have a book in mylar for 7 years the bag is still as good as new. the polybag after 7 years looks and feels like mess.

[InvstmntComcSuply]

 

I enumerated many of the physical differences that you can "see" a few posts up. However, it is the differences you do not see, that make Mylar a far and away better material for the preservation of paper collectibles than polypropylene or polyethylene.

 

Key Mylar points:

 

*Mylar is an exceptionally strong transparent film, 10 times stronger than polypropylene or polyethylene bags

*Mylar will not discolor

*Mylar contains no volatile chemicals which will migrate to the surface of the paper and cause damage

*Conservators in museums around the world use Mylar for storing their most valuable documents

 

One of the most telling points about polypropylene bags is that BCW (one of the largest suppliers to the comic industry) specifically recommends that you change their polypropylene bags every 3-5 years. You NEVER have to change Mylar bags, as they protect for over 100 years.

 

I should add that

*Mylar does not wrinkle or shrink like PP or PE and

*Mylar has a very low gas transmission rate which means less oxidation (browning of paper and dulling of inks).

There are probably more I am missing, just like I didn't think of these at the time.

[sakaridis]

What is the difference between Mylar and Polypropylene bags? Both are acid-free.

 

(in the context of preserving raw comics)

I do know that if you have a book in mylar for 7 years the bag is still as good as new. the polybag after 7 years looks and feels like mess.

Depending on climate and storage conditions, even 3-4 years might be more than enough for some of the cheap polybags to break down.