Glue on wet bottle
When labeling, the bottle is wet from the water sprayed over the bottle to wash down foam. On some bottles the glue flow down beneath the label on the glas screen. The bottle looks bad and it have a tendence to get glued in the bottom of the carrier/carton.
Is the solution to try to dry the bottle prior to labeling with a fan (The beer is cold and some condence might occur anyway)
Is there good and bad brands of glue?
Ideally, a bottle exits the rinse station which is immediately after the crowner and hopefully you have left enough space prior to the labeler to accommodate an air knife.
The purpose of an air knife is to gently push surface water down the bottle without vapourizing it as compressed air will do. Compressed air is high energy and creates a cloud of water which is carried along with the bottle and is significantly more expensive to run than a blower.
A cheap version of an air knife is an industrial vacuum on blow instead of suck going into a manifold made with 2" PVC pipe. It can be very effective. A proper 5-7 hp blower fan with piping to a knife manifold is a multi thousand $ proposition and creates a high flow of low energy air through an adjustable 1/8" gap that pushes water down and off the bottle.
Keep in mind, the bottle is still cold and damp or wet (depending on plant temperature and humidity). An air knife only improves your chance of getting a label on properly. You should never have adhesive running down the bottle. My guess is you are applying too much adhesive but I can't verify that from here. A properly set-up labeler applies a vapor thin layer of adhesive (casein or starch resin adhesive) onto a label which sets up within seconds of being applied to the bottle and leaving the labeler. Check with a reputable adhesive supplier on your adhesive. I have found that micro's do better with casein adhesives (milk based) that allow for less build up on the machinery and easier clean up.
I have encountered some adhesive companies or suppliers that don't work in the beverage industry and really don't have a clue what their doing so beware! Check with other brewers in your area. I'm sure someone can recommend a good supplier. Any effort to remove surface water from the bottle helps protect your package in storage (condensation damage) and improves the overall appearance of your bottle so I would highly recommend you look into it.
Thanks Rob for a fast answer and help. I have disuccessed with my glue supplier and I think that the final answer is that I had a too low temp of the glue (12 deg C) instead of 28-35 deg C that is recommended, which resulted in too much glue on the label so the glue wetted through the label and when I placed bottles together in the cartons they where glued together.
I would also recommend using casien glue in a wet bottle/humid environment application. Our bottles would sweat from the extreme humidity and we found that casien glue would set faster on wet bottles and minimize sliding body labels and flagged neck labels.