Paper Profile: OCC

How OCC is Used— Net Exports: 12%, Recycled Paperboard: 18%, Containerboard: 66%, Tissue: <1%, all other: <4%

Corrugated containers are the most popular material for shipping goods, with more than 90 percent of U.S. products shipped in corrugated boxes, according to the Corrugated Packaging Council.
   The word “corrugate” means “to form or shape into wrinkles or folds or into alternating ridges and grooves.” As such, corrugated containerboard is identified by the wavy, fluted layer of paper (called medium) that’s sandwiched between smooth sheets (called liner or linerboard).
   The most common corrugated has one layer of fluting between two smooth liner sheets. Some containers, however, have two, three, four, or more corrugated and linerboard layers for added strength. The fluting itself comes in varied depths and widths, designated by the letters A, B, C, E, and F as well as the term “Jumbo.” Corrugated is commonly differentiated by its caliper thickness, which can range from 0.045 to 1.135 inches, says the Corrugated Packaging Council. Liner, meanwhile, can come in weights from 26 to 90 pounds per thousand square feet.

The Paper Recycling King
In the paper recycling world, old corrugated containers (OCC) are at the top of the heap.
   For starters, OCC accounts for almost 50 percent by tonnage of all paper recovered in the United States. In 2000, 23.5 million tons of OCC was recovered in the United States, or about 48 percent of the overall 49.4 million tons of paper reclaimed that year, according to the American Forest & Paper Association (AFPA). OCC’s total was more than 21/2 times the tonnage of ONP, the next-closest competing grade. 
   OCC can also lay claim to the highest recovery rate, which reached a record 75 percent in 2000—3 percentage points higher than the next-highest grade.
   Plus, more OCC is exported than any other grade, with U.S. exports of OCC
totaling 2.7 million tons in 2000, more than 11/2 times the tonnage of ONP exported that year, AFPA reports.
   In terms of usage, the vast majority of OCC—84 percent—goes into the production of new containerboard (as medium or liner) or recycled paperboard. Only a small amount goes into the production of tissue/brown paper towels and other products such as kraft wrapping paper (see pie chart for details).

Specifications
There are three main specifications related to corrugated grades in ISRI’s Scrap Specifications Circular 2001:

(11) Corrugated Containers
Consists of baled corrugated containers having liners of either test liner, jute, or kraft.
Prohibitive materials may not exceed 1%.
Total outthrows may not exceed 5%.

(12) Double-Sorted Corrugated
Consists of baled, double-sorted corrugated containers generated from supermarkets and/or industrial or commercial facilities, having liners of either test liner, jute, or kraft. Material has been specially sorted to be free of boxboard, off-shore corrugated, plastic, and wax.
Prohibitive materials may not exceed 1/2 of 1%.
Total outthrows may not exceed 2%.

(13) New Double-Lined Kraft 
Corrugated Cuttings
Consists of baled new corrugated cuttings having liners of either test liner, jute, or kraft. Treated medium or liners, insoluble adhesives, butt rolls, and slabbed or hogged medium are not acceptable in this grade.
Prohibitive materials—None permitted.
Total outthrows may not exceed 2%.

   The ReMA specifications also include three specialty corrugated grades denoted as (11-S) Waxed Corrugated Cuttings, (12-S) Wet-Strength Corrugated Cuttings, and(13-S) Asphalt-Laminated Corrugated Cuttings. No specifics are provided for these grades. Instead, it is up to the buyer and seller to determine the specifications for each grade, and it is recommended that purchases be made based on sample. “These are unusual grades that are difficult to work with and move unless you have a specialty mill that can use them,” says John Ockenfels of City Carton Co. Inc. (Iowa City, Iowa) and chair of the standards and practices committee of ISRI’s Paper Stock Industries Chapter. 

Trends & Challenges
According to Ockenfels, the biggest challenge for OCC recycling can be summed up in one word—wax.
   Wax coatings, which help corrugated containers resist moisture, can gum up papermaking machines, form spots in new paper, and create problems during printing.
   Some mills consider wax-coated containers to be outthrows under current ReMA specifications, while others view them as prohibitives. “Some mills can use some waxed containers, other mills can’t use any at all,” Ockenfels points out. ISRI’s Paper Stock Industries Chapter tried to reach consensus on this issue but finally decided that “wax would be left up to each individual mill,” he says. “You just have to work with your consumer because it’s a technological issue.”
   Mills and packers agree, however, on the need to continue to educate OCC suppliers about wax-coated containers, with the goal of removing more of such containers from the OCC stream.