When coating fails to impress

摘要

Although the act of depositing a smooth and uniform coating of a prescribed thickness onto a substrate using an appropriate coating technology may go well-it doesn't always pan out that way.Thin substrates for instance can create unexpected manufacturing problems such as tearing,wrinkling,creasing,stretching and much more,all of which impact on yield,product quality and product viability.A relatively recent trend is the move towards ever thinner coatings; coatings deposited on ever thinner substrates and often,for very thin end products,such as OLEDs(Organic Light Emitting Diode)displays; batteries; catalyst layer electrodes; climate control components(such as solar reflective films); photo masks and electronic communicative packaging devices,etc.These thinner layers need to be deposited with precision in order to ensure end product performance is not compromised.Many types of defects can arise including pinholes; localised areas of a substrate that remain uncoated.Sometimes this is attributable to a coating flow that lacks uniformity and/or an inappropriate coating applicator selection but not always.Occasionally the problem is more to do with bubbles in the coating liquid as a result of air entrapment.