Cork Backing On Coasters Bubbling

r2uzenblot · Post by **r2uzenblot** » 17 May 2023, 11:11

I'm finding that on some of my cork backed coasters the cork bubbles up after pressing. Pressing is 180c for 70 seconds. Should I drop the time down?

pcwizme · Post by **pcwizme** » 17 May 2023, 12:59

I expect alas this is due to the quality of the coaster not the method, Are these from a reputable supplier?

r2uzenblot · Post by **r2uzenblot** » 17 May 2023, 13:46

pcwizme;152491 wrote:I expect alas this is due to the quality of the coaster not the method, Are these from a reputable supplier?

Yes from one of (I think) the leading two suppliers who exhibit at the big trade shows.

Mrteajunkie · Post by **Mrteajunkie** » 17 May 2023, 17:54

Are you pressing the print side up?
obviously heating the cork directly will cause issues.

r2uzenblot · Post by **r2uzenblot** » 17 May 2023, 19:34

Mrteajunkie;152495 wrote:Are you pressing the print side up?
obviously heating the cork directly will cause issues.

Yes print side up

Mrteajunkie · Post by **Mrteajunkie** » 18 May 2023, 06:38

I would certainly give the suppliers a call.

UK Printed Mugs · Post by **UK Printed Mugs** » 19 May 2023, 13:08

It is moisture. You need to pre-press upside down for 30 seconds then press the right way up.

DSF