Key variables affecting quality and consistency in rotary side-seam gumming are addressed in a new, complimentary four-page color brochure from National Adhesives, Bridgewater, N.J. These issues include extreme viscosity changes, which affect gum transfer, application and machining.
The brochure explains how to avoid problems by focusing on the gum’s formulation and viscosity, various factors of the gumming machine and steady supply to the gum box. For the most effective operation, the rotary side-seam gum must retain moisture and minimize foaming, and the brochure identifies the specific formulation that meets these requirements. The gum also must feature an ideal viscosity measurement—defined in the publication, along with suggestions for diluting.
The brochure provides details on gum box condition, roller roundness, gummer setup, metering to prevent gum drying and thickening, advantages and disadvantages of higher speeds and recirculation recommendations. It explains how on-demand feed systems reduce exposure of the seam gum to excessive agitation, which can cause foaming and an increase in viscosity, as well as provides specific guidelines for recirculation for envelope manufacturers who do not have on-demand feeding systems.
For more information, call (800) 797-4992 or visit www.nationalstarch.com.
- Companies:
- National Adhesives
