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Dual web construction is a hybrid product. It consists of two joined materials (i.e. label material and form bond). Dual web construction provides the ability to:

1. Perform multiple tasks at the same time (i.e. print a packing list and the mailing label simultaneously).
   
   
2. Join parts of a set (i.e. a membership form with a plastic membership card).
   
   
3. Assure the matching of data in the two components.
   
   
4. Reduce supplies and processing costs.

Pointil Systems provides continuous fanfold and cut-sheet dual web products of various sizes with both traditional hot melt and cold adhesive options.

WHY USE HOT MELT ADHESIVE:
Hot melt adhesive is used for joining non-paper substrates; tyvek with paper, plastic with tag, plastic with label.

WHY USE COLD ADHESIVE: Cold adhesive is available for joining paper and label substrates. This is particularly important for the use of dual web products used in newer laser printers operating at higher heat levels. These higher heat levels actually soften hot melt adhesives resulting in the disjoining of the paper and label segments! Lexmark only recommends cold adhesive for use in their laser printers. Lexmark has qualified Pointil Systems as an approved manufacturer of dual web products.

DUAL WEB VERSUS INTEGRATED:
Dual web construction has many advantages over integrated construction.

1. Dual web products are preferred over integrated products for laser applications In fact, Lexmark, a leading laser printer manufacturer, recommends dual web construction and does not recommend integrated construction. Again, Pointil is a Lexmark approved manufacturer.
   
   
2. Paper can be joined with a variety of label stocks having different facestocks, adhesives, or liners. With integrated products you must convert a section of the paper to a label or card by adding adhesive and liner to the back of the document. Therefore, your label or card must be made of standard paper. If a special label is required, the entire paper area must be of that special stock.
   
   
3. There are many more adhesive options available with label stock than applied adhesive used in integrated products. Standard label adhesives have a longer shelf life than applied adhesive.
   
   
4. Unlike integrated products, there are no loose edges on the back of the document. The liner patch on the back of integrated products may get hung up in a laser printer causing a jam or worse, actually pre-dispensing in the laser printer, exposing the bare adhesive to the internal path of the laser printer.

CONSTRUCTION RECOMMENDATIONS:

1. In cut sheet products, the leading edge, the first edge entering the printer, needs to be of uniform thickness. As such, the binding seam should not be on the leading edge. Additionally, the leading edge should be the thicker of the two stocks. For example, in a label/form product, the label section should be the leading edge of the document. If it is desired that the label appear at the bottom of the document, reprogram to print toe-to-head. This will enable the leading edge to be the label, but appear at the bottom of the document.
   
   
2. Binding seams: The binding seam, or overlap seam, is usually 1/4" to 3/8" wide. It is highly recommended that the facestock be removed in the overlapping area in order to minimize the thickness of the document. Furthermore, with the facestock removed, no imaging should be done in the overlap area.
   
   
3. Document thickness. Most cut sheet printer manufacturers recommend a maximum thickness of .007". This equates to the thickness of 100# tag. Most label stocks are under this thickness requirement. In addition, it is preferred that the differential in stock thickness of the two substrates be minimized. This allows for better stacking in the printer trays and contributes to better feeding.
   
   
4. Label choice: The primary concern with label stock utilized in dual web laser products is the liner. It is important to use a lay-flat liner. Most of the thinner lay-flat liners are re-moisturized for stability. They perform satisfactorily in laser printer.
   
   
5. Recessed facestock edges. With very few exceptions, adhesives tend to ooze from between the facestock and liner. When the facestock extends to the edge of the liner, the adhesive oozes at the edge of the document, leaving a tacky edge. This tacky edge creates buildup within the printer resulting in several printing problems. Jams, fuser roller damage, and frequent maintenance/cleaning occur in sheet fed printers. In continuous printers, adhesive ooze through the line holes results in feeding problems.
   
   
6. Packaging. Depending on the thickness differential of the two substrates in the dual web construction, it is recommended that cut sheet products be packaged in alternating stacks head to toe. This will provide for a more level stack within the carton and reduce product damage within the carton. Fanfold twinweb should be shimmed within the carton to provide a level-feeding path into the printer.
   
   
7. Perforations on the leading edge. Perforations cut into the leading edge of cut sheet products are not recommended because they may result in the document catching and being torn inside the printer causing jams and/or document damage. If perforations are parallel to the feed direction, they should be tied off at the leading edge.
   
   
8. Quiet zone. All sheet fed printers have a minimum quiet zone (non printable area) extending a 1/4" inward from each edge of the document. As no laser printing can occur in this zone, it can be used for preprinted instructions or for matrix removal.

©Pointil Systems 12807 NE Airport Way Portland, Or 97230 503.257.5097