| Ways to faster cure |
|
Faster adhesives | |
|
Accelerated cure by heated rooms | |
|
Limitations of conventional UV curing adhesives | |
|
Accelerated cure by Curex masterbatches | |
| Tag Heuer Monaco Replica |
|
Faster adhesives | |
| Disadvantages: | ||
| Shorter pot life of adhesive. | ||
| Compromise between different adhesive properties. | ||
| May reduce slitting time but still 8-10 days needed for full cure. | ||
| [back] |
|
Accelerated cure by heated rooms | |
| Disadvantages: | ||
| Heating a reel from outside may take up to 2 days before the reel is in heat- balance. | ||
| Higher risk of piping, curling and higher waste. | ||
| Heating of laminates with solvent free adhesives invites to telescoping. | ||
| Excess heat during curing may change final properties of adhesive. | ||
| Future CO2 legislation may forbid use of energy for this type of purpose. | ||
| [back] |
|
Accelerated cure by Curex masterbatches | |
| Advantages: | ||
| Very fast curing. Converting after a few hours. | ||
| In combination with some adhesives faster than UV curing adhesives. | ||
| Shipping in 24-48 hours possible. | ||
| Pot life of adhesives unchanged. | ||
| May offer higher final bond values for some adhesives. | ||
| More flexibility in adhesive formulations. | ||
| Faster reach of migration limits of uncured adhesives. | ||
| Use of aliphatic solvent free adhesives now realistic. | ||
| Cost reduction. | ||
| No change of equipment. | ||
| Disadvantages: | ||
| None known after 12 month in full production | ||
| Difficult to accept that adding the cost of Curex is in fact reducing the costs of converting. | ||
| [back] |
| |
Film Considerations When UV Laminating |
|
|
One of the substrates must be at least 20% transparent to UV
light |
||
| Polypropylene blocks 5-10% of UV light transmission |
||
| Polyethylene blocks 10-18% of UV light transmission |
||
| Polyester
blocks 30-50% of UV light transmission |
||
| Correct
Surface energy is critical for proper wetting out of substrate |
||
|
Preferred
dyne level of film for laminating is 42-46 |
||
|
Dyne
levels of 38 and below usually result in poor adhesion and
inconsistent performance |
||
|
|
||
| [back] |