Be the first to like this
In a presentation entitled "Beyond piano black", Tim Wright, R&D director at formable hardcoated film producer MacDermid Autotype, said that although black remains a popular colour, his company is working on "making black even blacker", with "some products already in the marketplace".
He said hard coating originally arose as a solution not only to improve scratch resistance, but also to overcome polycarbonate developing a blue tinge over time due to crystallisation. With regard to current concerns about recycling, Wright pointed out that the hardcoat is not thermoplastic, so it can be filtered out from the PC remelt.
A breakthrough came in 2005, when Autoflex XF (Xtraform) film with high formability and fairly high chemical and abrasion resistance was first used on the Mercedes S Class. The part involved 44 different components and was the first major automotive piano black application.
Wright said: "It was a leap of faith by Daimler, but they recognised the potential compared with paint spray and etching."
Piano black decoration has since reached Audi, Ford, Fiat, VW, and GM/Opel models.
However, Wright continued: "Designers grow tired of the same discussion [of piano black]. They are thinking 5-10 years ahead, as I do. I am not clever enough to think of everything, but I want to hear about what is required and make it happen - with passion and energy."
For example: new textured hardcoats used for the Autoflex S film, with low haze through use of micro-replication technology; or overcoming PC film limits such as its needing a post-cure hardcoat to meet automotive standards, and its short life in switch applications. Here, Wright sees potential for HiForm PE in an oriented PET (OPET) film, as it "has good flex life (ten times that of PC), is surprisingly formable as a pre-cured hard material, and is already used in membrane switches".
HiForm PE has been formed to 7mm depth and can handle sharp corner radii. But as it is limited in thermal soaking performance, MacDermid Autotype has a 2012 R&D programme "to make it work in auto interiors", Wright says. One area for OPET in future could be soft touch surfaces, where other soft touch solutions have inadequate chemical resistance.
Although MacDermid Autotype has been coating PMMA for 10 years, Wright said it is very soft at 100°C and has too low birefringence for displays. But he sees potential for Toray Picasus non-metallic lustre film for badges and chrome replacement. Picasus is a multilayer film with layers of different refractive index, so it looks like sputtered or aluminised film. It is also compatible with hard coats such as Xtraform and is formable.
Wright said MacDermid Autotype had offered textured black film 10 years ago, but it was "not really taken up". Now the time is right, Wright says, for areas of text or ones with, for example, bird and leaf designs.