Coating methods inkjet

The coating can be applied to the microprotrusions using known coating methods. Microprotrusion coating solutions can be applied by various methods, also by using inkjet technology (45). 

For example, a controlled deposition system inkjet-type coating method can be used that applies various substances only to certain targeted portions of a stent. A representative example of such a system has been described (67). A controlled deposition system can be used for the deposition of a substance on stent having a complex geometry. 

The functional layers having a liquid phase can be fabricated by slot-die, inkjet, screen and blade coating methods. However the functional layers not only have different coating characteristics but also have different film thicknesses, and therefore it is necessary to select the appropriate fabrication method for each functional layer. 

Using inkjet special substrate coatings is, most probably, the most widely used method to enhance inkjet printing quality for the SOHO (Small Office Home) markets. However, when dealing with commercial printing, e.g., wide format printers or non-porous substrates, top coats will neither guarantee the performance required by commercial customers, nor meet the cost goal required for most applications. 

A dispersant or a surfactant is preferably employed if inkjet printing is used for deposition. The optimal viscosity of the color coat is determined largely by the method by which the coat is applied to the lens. If the color coat is to be applied by inkjet printing, the viscosity of the ink should be less than 15 cP (93). A preferred composition is summarized in Table 7.13. 

Manufacturing methods are aiming to obtain a film, usually composed of multilayers. Some materials such as Kapton are often sold in a film form. However, for resistive sensors, the polymers need to be applied by using dip coating or spin coating techniques. Weremczuk et al. (2012) have reported the use of an inkjet printer to draw a specific pattern for the electrodes over a layer of Nafion . The printed sensor demonstrated satisfying results but the durability and long-term stability are still an issue. 

Typical processing methods - wet spinning (microfibers), spin coating, inkjet printing ... 

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