by Katy Ibsen, editor, PostPress, and Chris Van Pelt, THERM-O-TYPE

THERM-O-TYPE Corp., Nokomis, Florida, introduced the Glue-Tech model SA-1420 sheet-to-sheet gluing machine at PRINT 18 last fall. Glue-Tech provides a unique alternative for printers producing thick printed products with cohesive papers or manual gluing.

Most digital printers can only print on sheets up to 18pt thick. This makes production of products thicker than 18pt – such as premium business cards, announcements or reinforced end sheets – impossible using a single sheet. In addition, some products require multiple layers, not necessarily to increase product thickness, but to encase RFID chips/antennas or to enhance the product by inserting a colored layer between exterior sheets.

Traditionally, options have included cohesive paper or manual gluing; however, both come with limitations. Cohesive papers are effective, but expensive – often costing four to five times the price of non-cohesive sheets – and are only available in very limited sheet sizes, thicknesses, colors and finishes. Manual gluing uses relatively inexpensive equipment and materials while offering flexibility regarding sheet sizes, thicknesses, colors and finishes, but is a very slow and labor-intensive process during operation and clean up.

Using affordable, water-soluble, cold glues, Glue-Tech can bond a wide range of materials including papers, chipboard, magnetic sheets, micro flute board and some synthetics at speeds up to 1,500 glued sheets per hour using a single operator.

Glue-Tech uses an offset press-style suction feeder, with double sheet detect/interrupt, to feed bottom sheets onto an alignment table. After sheets are accurately aligned to an adjustable side guide, they are fed into a pair of pinch rollers that advance the bottom sheet through the glue application section of the machine. A sensor-activated pump automatically maintains the glue reservoir level and the quantity of glue applied to the bottom sheet can be accurately adjusted and controlled.

After glue has been applied to the top surface of the bottom sheet, the sheet is advanced to a headstop. The operator hand feeds the top sheets into a feed tray, with each sheet aligned to the headstop and side guide.

When sensors confirm the correct top and bottom sheet positions, the sheets are gripped and advanced through a pair of squeeze rollers to remove any air pockets and to evenly distribute the glue between the sheets. If the top and bottom sheets are not positioned correctly, the Glue-Tech will automatically stop and an error message will be displayed.

If the product requires three sheet thicknesses, two sheets would be glued together and then the two glued sheets would be bonded to the third sheet in a second pass. A large, full-color touch-screen, interfaced through a Windows computer core, is used by the operator to adjust and control the Glue-Tech.

Functionally, the Glue-Tech provides advantages and flexibility of manual gluing but with increased productivity, glue application control and sheet-to-sheet alignment consistency.

The Glue-Tech has been designed for quick and easy clean up. Glue in the feed tubing can be pumped back into the glue supply container, the glue feed tubing can be flushed automatically and a suction clean up system is provided to speed and simplify removing glue from the glue metering/application section of the machine.

Sheet-to-sheet gluing applications are diverse, growing and profitable. New technology, such as the Glue-Tech SA-1420, allows printers an effective method of producing thick printed products while minimizing material and labor costs.

Technical details:

Glue-Tech features include a touchscreen computer control, 14″ x 20″ maximum sheet size, 13.5″ capacity offset press-style air feeder and full-length registration table for the bottom sheets. Top sheets are handfed into a loading tray. The system offers precise glue application, accurate registration between the top and bottom sheets, top and bottom sheet position sensors, glue level sensor and pump, vacuum clean up system and throughput speed of up to 1,500 glued sets per hour.