Precision multi-layer coating consists of many sub-processes, each of which must perform optimally to create and bring a high-quality product to market in the shortest possible time, at the lowest possible cost. To optimize the coating process as a whole, while minimizing cost and development time, it is critical to work with a contract-coating partner that can effectively employ and interpret relevant coating process models.

Modeling the application and drying of coated materials can eliminate significant trial and error in lab, pilot, and production experiments, reducing investment in product development and scale-up. Successful toll coaters use extremely detailed models to predict critical factors in the coating process design, including speed range determination for coating a particular solution or multilayer product, and maximum drying rate.

This information makes it possible to estimate rough pricing for production quantities and feasibility of using the formulation with a particular process. Such methods can also reveal modifications required to make the product more coatable, dryable or able to be run at increased speeds. Modeling data can provide a high degree of confidence in the process setup when a coating trial is planned. In many first trials, modeling will result in production of high-quality material (featuring uniform coating and proper drying) from which the customer can provide prototype samples.

Well-developed, sophisticated models can make predictions for coating and drying of up to 10 layers. This presents a tremendous benefit to customers averse to spending significant time optimizing machine parameters. Sophisticated modeling processes also result in decreased time-to-market because coating partners minimize time in the lab, and time and money on the coating machine.

The models are sophisticated, but customers can easily provide the necessary details to develop a comprehensive model. These parameters include the type of substrate or web that will be coated (including thickness and width), desired layer thickness or laydown, rheology of each layer to be coated, and binder and solids concentrations. (Rheology is the fluid viscosity over a range of shear or flow rates and can be measured using less than one liter of solution.)

While modeling is very powerful, the coating partner’s experience is a critical factor in effective interpretation of results and formulation design. After analyzing the modeling data for a customer’s multilayer product, one of Carestream Contract Manufacturing’s expert engineers identified a productivity opportunity. By adjusting the concentration and rheology of several fluid layers, they increased the coating speed from 750 to 1100 feet per minute for the next production run – without costly trials. Since the final dry product construction was unchanged, very little product validation testing was necessary, and the client was delighted with the manufacturing cost savings realized.

When skillfully applied, modeling simplifies product and process development, shortens time to market, reduces cost and enhances quality.