| 1st Surface Printing |
Process of printing on the side of the label, typically the side opposite of the resin or not in contact with the resin. The graphics will be less durable unless a coating is applied. |
| 2nd Surface Printing |
Process of printing on the side of the label that will be in contact with the resin. The graphics will be more durable because the consumer will not contact the inks or graphics. Care must be taken when printing so that enough unprinted film is exposed to allow a bond or use inks that will bond with the resin and form a strong bond with the substrate. |
| Angel Hair |
Small hairs that are remaining after the die cutting process. |
| Blocking |
The tendency of two or more (potentially an entire stack) of labels to stick together in a stack or roll, especially under heat and/or pressure. |
| Bond Strength |
The force required to separate two surfaces which have been laminated or heat sealed together. |
| BOPP |
Biaxially oriented polypropylene. Film is stretched in both the machine direction and cross-machine direction to increase its strength. |
| Bubbling |
Label defect similar in shape to a blister where label is not firmly adhered to container. |
| Caliper |
Substrate thickness expressed in mils or points (1 mil = 0.001 inch) or microns (1 mil = 25.4 microns). Film thickness is sometimes referred to in gauge sizes. (1 gauge = 0.01 mil or 0.254 micron) |
| Cast Film |
Polyolefin film, usually polypropylene, which is not oriented after it is extruded. |
| Cavitated Film |
A co-extruded film consisting of a partially foamed or "cavitated" inner core layer and thin solid outer layers. This sandwich is much stronger, has better stiffness and has a higher yield than a solid mono-layer film of the same caliper. |
| Cling |
A very mild form of blocking where the plies can be easily separated without visible damage to either surface. |
| COF |
Coefficient of friction is the ratio of the frictional force to the force acting perpendicular to the direction of motion. |
| Static COF: The ratio of the force needed to start the motion between two surfaces in contact to the the force acting perpendicular to the direction of motion. |
| Kinetic COF: The ratio of the force needed to sustain the motion between two surfaces in contact to the force acting perpendicular to the direction of motion. |
| Curl |
A label edge or corner that does not lay flat on a plane surface. |
| Delamination |
When the label does not adhere to the plastic substrate to any degree. |
| Die Cut Labels |
Labels cut from printed sheets or web using one or more die cutting processes (rotary, high die, counter pressure, steel rule) |
| Discoloration |
Color shifts on the printing or decoration on the label. |
| Double Picking |
Two or more labels which are stuck together when fed from a magazine stack. |
| B-IML |
Blow mold in-mold labeling. |
| Edge Welding |
Labels whose edges are fused together during die cutting. |
| EVOH |
Ethylene vinyl alcohol, a polymer used for gas barrier in laminations. |
| Feathering |
Uneven trim edge where the ink protrudes as feathers. This is caused, in part, by dull dies or dies that are not properly matched or set. |
| Flagging |
Label defect where, at molding, the edges are lifted from container. |
| Gate |
The orifice through which resin flows from the runner to the part. Gates are different sizes and configuration depending on the resin and geometry of the part. |
| Gravure |
Printing method which transfers ink or coating to a substrate from tiny cells etched in a metal cylinder. |
| HDPE |
High density polyethylene |
| Heat Seal Coating |
Adhesive coating which is non-tacky at room temperature but becomes sticky when heated. |
| High Die Cutting |
Off-line process for punching out labels from a stack of 500 to 1,000 label sheets in a single stroke using a hollow cutting tool. |
| IMD |
In-mold decorating. |
| I-IML |
Injection mold in-mold labeling. |
| IML |
In-mold labeling. |
| IML Foot |
The ledge that is located such that the resin will contact the back of the label prior to the edge. |
| Ink Wash |
An area on an label where the color appears faded or washed after molding. Typically caused by heat shear or concentration. |
| Lenticular Lens |
Is an array of magnifying lenses, designed so that when viewed from slightly different angles, different images are magnified. |
| Lenticular Printing |
Is a printing technology in which a lenticular lens is used to produce images with an illusion of depth, or the ability to change or move as the image is viewed from different angles. |
| Match Metal Die |
A more expensive die used for cutting 3-D appliqués. This die is constructed from hardened tool steel and the punch and die are precision matched to form the cutting edge. This type of die is useful where the cut is not on a planer surface or where you need to cut on the side of a 3-D appliqué. |
| Offset Lithography |
Printing method in which a grease-like ink is transferred or "offset" from the image to a rubber "blanket" cylinder and then to the substrate. |
| OPP |
Oriented polypropylene. |
| Orange Peel |
Textured or micro-pitted label surface appearance resembling the surface of an orange. |
| Over-coating |
A clear varnish or coating applied over a printed surface to protect it. |
| PCR |
Post consumer resin. |
| PET |
Polyethylene terephthalate (polyester). |
| PP |
Polypropylene. |
| Pick and Place |
Articulated robotic device which picks up a label from the magazine stack and positions it in the open mold. |
| Rotary DieCutting |
Process of punching out individual labels from the surrounding matrix using a tool mounted on a cylinder. |
| Set-off Powder |
Starch-based powder used at end of sheet fed offset press to prevent face-to-back transfer of wet ink in stacked sheets. |
| Sink Marks |
Depressions on the surface of a molded part caused by a low pressure situation in the injection molding process. This can be caused by under-packing of the part due to process or by achieving gate seal prior to a thick section being solidified. |
| Slip |
A high slip normally refers to low COF and a low slip refers to high COF. |
| Spot |
Dot shaped mark on the label caused by ink or foreign material during the printing process. |
| Sprue |
The part of the runner formed by the resin flowing through the sprue bushing, a feature of the mold that interfaces with the injection machine nozzle. |
| Sprue Gate |
Where the part is filled directly from the sprue bushing of the injection mold. This leaves a large "carrot" looking gate remnant that must be trimmed. |
| Steel Rule Die |
A less expensive die used for cutting the label. This die is manufactured by bending a steel rule cutting blade around a form such as wood. The cutting action is performed between the sharp edge of the steel rule and a flat surface of wood, plastic or metal. This die is good for simple and flat cuts. |
| Stress Mark |
A typically white colored mark that appears on the label when it is formed, bent or creased. |
| T-IML |
Method where die cut label is placed in a mold, a plastic sheet is indexed over the mold then heated and forced into the mold forming the container. |
| UV Flexo |
Same as flexo except it uses 100% reactive inks cured by UV radiation. |
| Vacuum Port |
Small openings in mold which hold labels in place during molding. |
| Valve Gate |
A heated gate used in injection molding to produce a remnant free part. The only thing visible is a circular impression similar to an ejector pin mark. The straight or tapered pin valve is actuated by hydraulics or pneumatics on a timer. This gate can be useful to direct the plastic flow behind the IMD appliqué and to reduce shear and ink wash on the appliqué near the gate. |
| Viscosity |
Resistance of a coating or ink to flow under applied force. |
