Cleaning Glue Spreaders

How to maintain glue spreaders for peak performance. May 9, 2001

General Information
Glue mixers and speaders should be thoroughly cleaned at the end of each working day. When mixing and spreading equipment is used for various types of glue, a neutralizing process should be used. This should be followed by a water rinse in all cases.

Three types of neutralizing solutions are commonly used:
Alkaline
One half pound of washing soda or trisodium phosphate dissolved in two gallons of water.

Acid
One cup of vinegar in two gallons of water.

Ammonia
One half cup of household ammonia (approx. strength=5%) in one gallon of cool water.

In all cases, wash spreaders thoroughly with warm water. Tighten doctor roll against rubber roll and fill with neutralizing solution. With glue spreader running, clean grooves with stiff brush. Open doctor rolls and flush with clear water. Remove dams and thoroughly clean. Specific neutralizing solutions: The solutions suggested for the following glue mix changes are:

- Urea resin to casein-Ammonia solution
- Casein to urea resin-Acid solution
- Casein to polyvinyl acetate-Acid solution


- Polyvinyl acetate to casein-Alkaline solution
- Polyvinyl acetate to urea resin (and vice versa)-Alkaline solution
- Phenolic resin to urea resin-Acid solution
- Urea resin to phenolic resin-Alkaline solution
- Polyvinyl acetate to phenolic resin-Alkaline solution
- Phenolic resin to polyvinyl acetate-Acid solution

Caution
The alkaline and acid materials mentioned above may be irritating to skin, eyes, nose and throat. Avoid prolonged or repeated skin contact. Use with adequate ventilation. In case of contact, immediately flush eyes with plenty of water for at least 15 minutes. Get medical attention.

This article was provided by Kent Pitcher of Custom-Pak Adhesives, Inc.