cost-effective photochromic dip coating machine, reports Simon Jones
Since photochromic lenses came to market in the 1960s, they have been controlled by handful of major corporations. Production has remained costly, which has been passed on to opticians and their patients.
Shropshire firm Shyre is hoping to challenge the corporate hegemony with a new dip coating machine, designed for ophthalmic labs and larger optical chains, that can produce photochromic lenses and coatings at a fraction of the cost.
Umbra has been in development since 2013 and company directors, Lee Gough and Dan Hancu, first began experimenting with the idea of a dip-based photochromic coating in a garage.
‘The concept of a dip coat photochromic was a real, “what if?” moment for us. You had world leading experts in dip coating automation and photochromic dye production and it seemed like a logical step.
‘The results of the first experiment wouldn’t lead you to believe it was possible,’ says Gough jokingly.
‘We got a workshop and gave up our jobs to work full time on the project at the end of 2013. We then spent 12 months developing the process and designing the machine prior to producing a prototype in 2015. The same year, we won young business and technology, enterprise and innovation awards.’
Expertise
Gough’s background lies in engineering and automation, with a wealth of experience in producing dip coating machines. Hancu brings expertise from within the photochromic lens production sector, with a particular focus on in-mass production.
Both were ‘dragged’ into optics by their fathers. Gough’s father, David, has worked in lens cleaning and coating for over 25 years, while Andrei Hancu, like his son, has been working in photochromic dye production.
Gough says their knowledge of the photochromic market highlighted two inhibiting factors, which ultimately led to the development of Umbra. The existing branded lens of the time was very good, but it was expensive and the cheaper product category from the Far East often was not of high enough quality, he says.
‘Whichever route an ophthalmic lens lab went down, it required vast amounts of stock, in all the different photochromic colours, lens materials and finishes – it has to be hundreds of thousands of pounds worth,’ says Gough. Hancu recalls that a lab in Brazil kept more than $1m of branded photochromic lens stock.
Umbra-lievable
With their new machine, Gough and Hancu say they have found a middle ground. Labs can produce photochromic lenses in a more cost-effective manner and avoid the financial burden of stock holding.
The company needed not only to produce a bespoke machine, but the coatings themselves. The result is a photochromic coating that can be applied to almost any type of ophthalmic lens, not limited by material or index. In-house accelerated time testing has found that the photochromic lifetime is comparable to other brands. Activation and fade back times are said to compare very favourably to branded lenses. The knock-on effect of the time spent developing a photochromic coating suitable for a dip coat, is that the company has used its expertise to develop its own processes for anti-scratch and anti-fog coatings. Shyre is also an official UK distributor for PPG products.
The process
Finished lenses, either stock or post surfacing, are loaded in batches onto a conveyor belt that leads into the machine prior to five stages of chemical cleaning and drying. When this is complete, the next stop is coating dip tanks, where the photochromic and anti-scratch coatings can be applied. Lenses can then be edged.
The entire coating process is controlled by bespoke software created in-house, implemented by Beckhoff components. Gough says it was important to make the software as easy as possible to use, allowing lab technicians to benefit from a gentle learning curve. Batch data can be logged, along with machine data to identify problems and refer back to coating properties. Features like tint strength and graduations are controlled in the software by very accurately regulating the dipping speed. Gough says parameters for this can be accessed and changed easily. Shyre will also provide full software and hardware support.
Labs can make their own photochromic coatings in an almost limitless colour palette. Dye tanks can be changed on site with relative ease, something which Gough says he paid special attention to when building and designing Umbra.
Until recently, photochromic colours from mass-producers were limited to grey and brown. The recent addition of green has not moved the game on as many would have hoped, thanks to its graphite appearance. Colours and gradients should be of high importance to labs, as anything that can broaden the appeal of photochromic lenses to a younger patient base needs to be embraced. In addition, the cost-effectiveness of Umbra’s lenses should open up what has been a relatively costly option, to a new cost-focused younger market.
Shyre is a company full of ideas, with Gough and Hancu often having to force themselves to stick to one concept stream at a time. That focus has resulted in the Umbra machine, but the company’s future plans are exciting. Experimentation with monomers, tints and frame materials has yielded encouraging results. It will not be too long before Shyre is back in Optician.