According to this article black and white is back in fashion this year. Hopefully one day soon brown and beige will be back and I will once more be a fashionable gent about town!
In 2009 I blogged about a row in Derby about the yellow colour of taxis. But times change. Things move on, Today I am reading about a problem in Durham – for those who don’t know, Durham is in the north-east of England – about white taxis!! Apparently, this week ten drivers stormed out of a meeting with councillors over a proposal to adopt a policy for all-white colour taxis in the county of Durham. The argument for white taxis is that it would make them stand out and ensure that customers knew which taxis were legitimate. Sounds pretty sensible to me. It would work because white is a very unpopular colour for cars in the UK. I have heard that second-hand car salesmen refer to white as six-week white because it takes 6 weeks longer to sell a white car than other coloured cars. Whereas in other parts of the world, I have noticed in my travels that white cars are quite popular. Perhaps there is a business opportunity here – to export the unpopular white cars to places where they may sell for a premium.
It’s often thought that black, white and grey are mature and sophisticated colours and that saturated reds and yellows are childish colours. Part of the reason for this is that the Romans and Greeks didn’t use colour. All those classic statues we see in museums are achromatic. However. this may be all based on a misunderstanding. At a CREATE conference in Italy last year I first came across the idea that the Romans and Greeks used colour quite extensively but that over the centuries the colour faded. Today I saw this story in the popular press.
An exhibition of work – Gods In Colour: Painted Sculpture of Classical Antiquity – recoloured as it is believed to have originally been features more than 20 full-size colour reconstructions of Greek and Roman works. Currently on show at the Pergamon Museum in Berlin, Germany.
I was reading on a web page that white is the usual response if you ask people their favourite colour – http://www.pressdistribution.net/14735/apple-iphone-4-white-show-true-colour
I don’t think its true. Most studies show that people’s favourite colour is blue. I have never heard of a study that found white to be the favourite colour. The article was about the iPod though and we all know that the use of white was an inspired choice by Apple. The white earphone leads have become iconic and are part of the brand that consumers buy into by the millions. In fact, I think this is a very interesting phenomenon – there is a lot of research that shows that people prefer one colour to another. But what use is it? Over the last few years my research has focussed on the context of colour preference; that is, which colours would be most effective when used for a particular product (and by extension, for a particular market).
Does wearing a white T-shirt really help you keep cool in the summer?
Absolutely. White objects tend to reflect most of the light that falls upon them no matter what the wavelength in the visible spectrum. Objects are often coloured because they selectively absorb certain wavelengths of light preferentially compared with other wavelenghs that are then reflected. But what happens to the light that is absorbed? Well, in most cases dye or pigment molecules absorb the energy and go to a higher energy state. But as every physicist knows, energy must be preserved. Eventually, the energy is released, usually in the form of heat. Now an object which is black is a very strong absorber and often absorbs much of the light at all wavelengths in the visible spectrum. Therefore a black T-shirt will heat up when exposed to the sun when compared with a white T-shirt.
This idea has been taken further by a team of MIT graduates who have developed roof tiles that change colour based on the temperature. The tiles become white when it’s hot, allowing them to reflect away most of the sun’s heat. When it’s cold they turn black and absorb heat when it’s needed.
In their white state the tiles reflect about 80% of the sunlight falling on them, while black they reflect about 30%. That means in their white state, they could save as much as 20% of present cooling costs, according to recent studies.
The tiles use a common commercial polymer in a water solution. That solution is encapsulated — between layers of glass and plastic in their original prototype, and between flexible plastic layers in their latest version — with a dark layer at the back.
When the temperature is below a certain level the polymer stays dissolved and the black backing shows through, absorbing the sun’s heat. When the temperature climbs, the polymer condenses to form tiny droplets, whose small sizes scatter light and thus produce a white surface, reflecting the sun’s heat.
The team was one of the competitors in this year’s Making and Designing Materials Engineering Contest (MADMEC) a competition for teams of MIT students.
For further information see http://thermeleon.com/