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WATERBASED REMOISTENABLE ADHESIVES
These products were developed because of varied needs on the part of the pressroom for water remoistenable adhesives.
Description
These products are made to run cleanly on all types of pattern gluing and extrusion equipment to
yield a smooth and consistently remoistenable adhesive film.
They are available at various viscosities. This allows the printer to select the product that runs best on his equipment. They are normally supplied to dry either clear or tinted. They can also be flavored in mint or wintergreen.
These products provide lay-flat and non-blocking properties with a minimum of misting at high web speeds. They can be applied as spot or overall stamp applications.
The remoistenable properties, even at relatively low coating weights, provide faster drying and higher web speeds. They work well on both coated and uncoated papers.
Usage
Adhesive viscosity is important for proper application. To maintain the proper viscosity, it is best to circulate the adhesive (from the applicator to the holding container). Dilute slightly with water should the viscosity build up. Chill the container should the adhesive get warm.
Be sure that the applicator rollers are clean and check adhesive metering equipment to assure proper operation. Do not allow applicator to hit pad with excessive pressure.
When applying by a pattern gluer, circulate the adhesive between the drum and the applicator pan. Always maintain an adequate amount in the pan. Do not generate foam.
Maintain proper viscosity by routinely using a #4 or #5 Zahn cup. Add water only when necessary to thin. Do not over dilute.
A smooth application is required. Avoid high spots or ridges. Too heavy an application can cause build-up on chill rollers as well as create offsetting due to inadequate drying.
Insufficient drying may not always be apparent to the touch. It may feel dry but still contain moisture.
Cleanup of equipment is easier when adhesive has not dried out. Hot water is recommended.
Adhesives should not be coated onto (or be made to adhere to) heavily inked areas. Remoistenable adhesives do not adhere to offset inks.
Adhesive testing should be done right off press for quality control purposes. Allow the glued area to dry fully first.
Storage
Store at room temperature. Avoid excessively high or low temperature. Do not contaminate unused adhesives with foamy or dust laden used adhesives. Do not modify adhesive without consulting your supplier.
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