Mechanical? - 'Scuffing' inside case of 20 slabs!? 2 2

[Picture*Books]

I've submitted about 500 books this year, a mix of Golden, Silver, and Moderns. I recently received back two Silver Age submissions and nearly all of the 25 books in each have a vertical white streak along the left spine edge. Some have a similar white streak along the right edge. None of my other slabs have this defect. Is this a mechanical or something gone wrong with the slab sealing process?

In the attached you can see the white streak running nearly the entire length of the left edge of the comic's spine.

[Lightning55]

If you're referring to the white steak about 1/4" left of the comic's spine, that is the encapsulation sonic seal of the inner well.  It's on the right side, too.  I don't see any other type of scuffing.  Maybe I am missing it.

[Picture*Books]

On 6/25/2023 at 12:13 PM, Lightning55 said:

If you're referring to the white steak about 1/4" left of the comic's spine, that is the encapsulation sonic seal of the inner well.  It's on the right side, too.  I don't see any other type of scuffing.  Maybe I am missing it.

So on all of the slabs I have received this sonic seal is transparent. On these two orders of Silver Age books the sonic seal is white. Is this a manufacturing defect?

[Lightning55]

On 6/25/2023 at 5:31 PM, Picture*Books said:

So on all of the slabs I have received this sonic seal is transparent. On these two orders of Silver Age books the sonic seal is white. Is this a manufacturing defect?

Not in my opinion, but who counts that?  Even on the sides of the case itself, there can be white areas where the plastic joins.  It's a weld. 

If it has been transparent in the past, just lucky.  Amazing you can sonically weld 2 pieces of plastic together without a milky look.  The plastic has to melt to join.