Technology - thermochromic pigments to graphene

thermochromic materials

change colour at specific temps. change in temp causes the liquid crystals to re-orientate which brings about the change in colour

2 materials used to create thermochromic effects

liquid crystals, leucodyes

what products are liquid crystals used in

mood rings, strip thermometers, LCD displays in calculators

what products are leucodyes used in

novelty tshirts, coffee cups and paper receipts

photochromic materials

undergo colour changes induced by exposure to different lighting conditions

products that use photochromic materials

nail polish, sun blinds, jewellery, uv radiation indicators

phosphorescent pigments

absorb energy and release it slowly in the form of light

advantages of phosphorescent pigments

after absorbing light they can glow in the dark for up to 12 hours, material is stable, non-toxic, no radioactive additives, good weatherability

applications of phosphorescent pigments

clothing and shoes, escape route signs, watches, toys, sporting goods

what is a reflective film

a material used to imrpove energy efficiency by lowering the amount of heat entering a building as a result of sunlight

benefits of reflective films

increasing privacy, shatter resistance, lowering amount of heat entering a building, reduce the amount of ultraviolet light that can damage furnishings and fabrics

what is a hologram

a flat surface that under proper illumination appears to contain a 3d image.

what are the 3 types of holograms

reflection, transmission, embossed

what is a reflection hologram

illuminated by a white light source on the viewing side of the hologram. the light is reflected from the hologram to show the image

what is a transmission hologram

viewed by illuminating from the rear with a laser. very sharp detailed and image can have greater depth

what is an embossed hologram

embedded on a thin plastic film backed with reflective aluminium. The aluminium reflects incident light back through the hologram activating it. commonly found on consumer goods and credit cards

liquid crystal display

an electronic device that operates by applying a varying electric voltage to a layer of liquid crystal, thereby inducing changes in its optical properties.