A blister package consists of a formed piece of PVC plastic attached to either a adhesive coated paperboard or foil(go to foil/pharm). The paperboard is manufactured specifically for blister packaging, and printed with special wax-free inks. Both ingredients are essential to blister packaging, and without both, the blister will not adhere to the paper.
The cards are printed in one of 2 ways. In cases of very large quantities or where specific color matches are very important, a dedicated run of cards is used. For lowest cost and fastest turnaround, cards can be printed on a "gang" or "combination" run. Because of it's low cost, the Gang run is often the preferred type.
A blister package consists of a formed piece of PVC plastic attached to either a adhesive coated paperboard or foil (go to foil/pharm). The paperboard is manufactured specifically for blister packaging, and printed with special wax-free inks. Both ingredients are essential to blister packaging, and without both, the blister will not adhere to the paper.
The paper and plastic are joined together in a blister sealer, which is essentially a hot plate which presses down on to a tool which has been custom made for the blister and card combo. The tooling is made with a cavity to fit the outline of the plastic piece, and a raised felt or rubber gasket is on the face of the tool, shaped to match the outline of the cavity. The blister flange (the part that seals to the card) will lie on the gasket when inserted into the tray cavity up. After the product is inserted, the card is put on top face down. Spring loaded disappearing pins outline the card area, to locate the card properly.
After the blister, product and card are loaded, the tray is indexed into the heating station, where a hot plate(appox. 300F) is pressed down upon the tool. The combination of heat pressure is enough to active the adhesive on the face of the card and creat a bond between plastic and paper, and a finished product
After the cards are printed, a clear adhesive is applied to the face of the cards. This adhesive will later be used to affix the plasic blister to the card. There are two types of blister adhesive, water based and solvent based. Water based is much more widely used because solvent based requires expensive equipment in order to process.
However, in our opinion, solvent coating provides a much superior seal. it not only seals stronger, but it seals faster, at a lower temperature. These two factors are very important. Obviously, a faster seal means faster production. The seal time can be cut from an average time of 3 seconds at 325F down to 1.5 seconds at 250F. The temperature aspect is very important because when cards are heated to high temperatures, they tend to curl as they cool down. The lower the temperature, the less curl.
Another factor that is very important when sealing is the temperature range. To high a temperature can be almost as bad as too little. Solvent coating has a much wider window of sealability. This range is important if you have a smaller or older machine. In these machines, the heating elements can be either inconsistant across the sealing head or fluctuate. The wider range afforded by solvent coating provides a greater margin for error.
