Contract coaters, also called toll coaters, are companies that provide web-coating services for companies, research centers, academics, and other functions which may not have the overall coating-process capabilities and the technology that need to completely develop and manufacture web-coated products. They can be used for the complete coating process: prepare solutions, coat, dry wet film, and convert roll stock to usable sizes. Or they can be used for only specific functions that are needed, such as coating and drying.
Contract coater capabilities
Contract coaters have extensive process and analytical capability to coat and dry products from solution preparation to final size reduction. However, the specific capabilities are unique to each contract coater, and their capability must be analyzed to determine if the contract coater can meet product requirements. Many toll coaters have methods to coat a wide range of coatweights using both aqueous and solvent-based formulations. Facilities include pilot and manufacturing coaters, solution-preparation operations, and quality and analytical testing. These various services are available on a fee basis.
The following summaries the general coating-process functions typically available:
- Prepare solutions
- Can use aqueous and solvent-based materials
- Handle a range of substrate types and thicknesses
- Treat, clean and laminate substrates
- Perform a variety of coating methods in single and multiple layers
- Offer several drying types: impingement, non-contact floatation, infrared, microwave
- Have available complete laboratory-testing capabilities and on-line inspection
- Use various process analytics
- Offer both pilot-line and full-production coaters
Contract coaters also typically have all types of coating methods at the ready. These include slot-die, reverse-roll, forward-roll, reverse-gravure, direct-gravure, Mayer-rod, knife-over-roll, polishing-bar, multilayer, slide and curtain coating.