Liquid Crystal Formulations

Thermochromic Liquid Crystals are highly temperature sensitive, changing through many colors. As temperature is increased, Liquid Crystals go through color changes from red to green to blue. Liquid Crystals are reversible and can be used repeatedly.

Liquid Crystal technology reacts to fluctuations in temperature. They can be formulated to react to temperatures between -30°C (-22°F) and 120°C (248°F) and react to changes in temperature as small as 0.1°C (0.2°F). They are also accurate up to +/- 1°C, and if stored and used correctly, they can remain functional for several years.

• Protective Film – Polyester or Polycarbonate
• Graphics – Printing Ink
• Temperature Window – Liquid Crystal Ink
• Black Backing – Printing Ink
• Adhesive & Carrier – Modified Acrylic with Polyester Carrier
• Shelf Life: 12 months from invoice date
  when stored in a cool dark environment between
  18°C – 22°C and 64°F – 72°F at 50% relative humidity

Custom Products

Due to the nature of construction, we can produce these in any design or shape. A full custom manufacturing service is available meet customers’ precise requirements. Please contact us for details.

1. Standard Red, Green, Blue Type

These are the original TLC Mixtures which have been used in producing Thermometer Labels since the late 1970s. Normally printed onto a black background, they initially show in a black state below their temperature rating. Next, they pass through the colors of a rainbow as light is reflected at different wavelengths as they pass through their “liquid crystalline” state. Finally, they show as black again once the temperature is outside of the range and are fully liquid in their isotropic state. Accurate to +/-0.5°C, these TLCs can be used to produce thermometers with a resolution as low as 0.5°C for use in hospitals.

Here you can see this type of TLC used in an example of a thermometer. Three colors can be seen as each window is a different liquid crystal phase. You should read the green window as the temperature, so in this case the temperature is 15°C. If there is no green showing, then the temperature is between the red and blue windows. Temperatures between -30 and 120°C can be produced.

2. Easy Read Single Color Below Type

These were initially developed by LCR Hallcrest in the late 90’s in response for a need of a simple fridge thermometer that would be easily understood. From this a new generation of temperature indicators, using these materials, which sharply changes color going from a colored state below their rating to black when above it, were developed. While still accurate to +/-0.5°C, the resolution is only possible at 2°C in multi event products.

Due to the single-color change, these products are easier to read than the traditional RGB ones. They are manufactured in the same way as the RGB products. However, since they must be coated around 50% thicker than the RGB type in order to show bright colors, this means a third print is needed. These SCB TLCs can be produced in green, blue and red. The brightest of which is green.

3. Easy Read Single Color Above Type

These were developed to allow and new range of products to be used due to requests from customers to be alerted when temperatures exceed a temperature rather than fall below them. These materials sharply change color going from black below their rating, to a colored state when above. Accurate to +/-1°C with a recommended resolution of 2°C in multi event products.