The Constantia Flexibles Labels Division of Spear Inc. recently announced that it has found a way to make pressure sensitive labels compatible with recycling methods for bottles molded from PET (polyethylene terephthalate) plastic. This is a breakthrough, says the company, because it offers an affordable and environmentally friendly solution for bring pressure sensitive labeling to the 400 billion PET bottles the world uses annually.

The announcement got us thinking about label terminology in general. As an editorial reference, we compiled the following mini-glossary of label type definitions. Please let us know if it needs polishing or adding to:


After printing on large-format sheetfed or web presses, stacks of label sheets are either diecut into their desired shapes or cut into individual rectangular shapes and stacked (hence the name).

Extended content

Extended content labels provide space for more graphics and copy through the use of multiple pages. Often called booklet labels or expanded text labels, they increase the amount of space available for text and graphics.


In contrast to pre-glued self-adhesive labels, glue-on labels get their adhesive during the label application process. The wet adhesives used are usually starch- -and-water based.


Made from various substrates, in-mold labels are diecut to size or preformed and inserted into the mold prior to injecting resin. The label bonds to the surface of the molded part when a thin layer of the label re-melts and solidifies with the resin of the part.

Pressure sensitive

Because the dry adhesive backing of these labels makes them permanently tacky, they can be applied to surfaces on contact with finger or hand pressure. They need no activation by water, solvent, or heat in order to stick.

RAS (roll applied shrink)

Shrinkable roll-fed film labels are applied to a container using a roll-fed labeler. The labeled container then passes through a temperature controlled shrink system that uses hot air to shrink the label tightly to the surface.

RFID (“smart”)

RFID stands for radio frequency identification. A smart label consists of an adhesive label embedded with an ultra-thin RFID tag inlay. The tag inlay can be encoded with fixed or variable data. The label also can be programmed and reprogrammed while in use.


Shrink sleeve

Heat is used to shrink film labels onto contoured container surfaces that would be difficult for standard adhesive labels to cover. A shrink sleeve label can be applied to just a portion of the package or wrapped for full-body, 360º coverage.

Stretch sleeve

Stretch sleeves are one piece, 360º, closed-loop labels applied with equipment that opens and stretches the sleeve onto the container. The “memory” of the film makes it adhere to the container—no glue is needed.


Inkless direct thermal labels are chemically treated to darken when a thermal printhead applies heat to the surface of the material. Thermal transfer labels get their appearance from an inked ribbon. The thermal printhead melts the ink from the ribbon onto the label surface to create the printed image.

Wrap around

Wrap around labels extend around the entire surface of an object, usually with one end of the label overlapping other end.