Is it normal for Kem Cards to cup like this? (3 Viewers)

[maxim_666666]

But why are they sometimes straight and then bend later? There are only two answers to this:
1) you were lucky and got cards from flat sheets! They will remain that way permanently.
2) Humidity affected your bent cards, making them temporarily flat.
I just conducted a simple experiment with a wet wipe and a card made of cellulose acetate (blue Modiano Platinum and PVC ( Modiano Cristallo).
Start

4 hour later.
The acetate card became flatter, while the PVC card bent like a banana.

After 12 hours, both cards returned to their original state.

 

[maxim_666666]

However, I must note that I do not consider this a drawback.
Acetate cards are very good and definitely better and more pleasant than PVC (not always, but very often). And if the price is reasonable, I would choose acetate cards without hesitation.
For example, with high-quality paper cards, no one is bothered by a slight bend, and overall, I like that it makes it easier to pick cards up from the table. On the contrary, it irritates me when I struggle to lift a flat PVC card from a flat table using my nail or another card.

 

[maxim_666666]

And I also contacted a major Modiano card dealer in Italy and he promised to check with the factory to see what was going on with the cards. He was surprised that people thought they were bent. Obviously, it's on Kem, but it's exactly the same situation.