"In North America, by volume, the most commonly used liners are made of super calendered kraft (SCK) stock, in calipers of 2.5 mil and 3.2 mil," says Todd Schweigert, director of marketing for Loparex, Willowbrook, IL. "Label converters traditionally use 2.5 caliper.
Liners made from films make up about 15 to 20 percent of the release liners used in the label industry, says Schweigert
, but are growing at a faster rate than papers.
"It's a natural kraft paper with polypropylene extruded on one side," says Schweigert
"It fills a gap in the market between film and paper liners, and it makes up another 15-20 percent of the market for us."
The release capabilities of the liner might be specified by the end user, and the label converter quite often knows what type of liner to use for what application.
Still, opinions vary as to how much a converter should know about release liners.
"A label converter's customer traditionally needs to know very little about release liners other than they work," says Schweigert
, says Schweigert
, segregates its release liner markets in seven ways: label, graphic arts, medical, hygiene, composites, tapes, and industrial.