Clevertex - Grado Zero Espace Srl

The American company Color Change Corporation145 sells Thermochromic Leuco Dye. The LD
materials are coloured in their cool state and translucent in their warm state. For LD clearing points
below 34°C, it takes 2-4°C to change to clear. These dyes are micro-encapsulated with an average
particle size of 5 microns.
A research group at XS Labs succeeded to create an information pattern in a dynamic textile by using
the embroidery technique. The embroidered stitching material was a heat conducting material, which
was placed beneath a thermochromic textile. So, they presented an apron for a PDA to express
wearing and tearing. The apron has two separated fabric layers, one at the bottom with heating
threads and one above with the thermochromic fabric. The two fabric layers contact each other
depending on the movements of the wearer.
Other chromic material
Recently, the firm Procter & Gamble announced their intention to launch an intelligent slip on the
market. The aim is to notify the female wearer when ovulation is coming or when she will start to
menstruate.
To determine the ovulation, a layer of silicones is used covered with a thin plastic film. The silicones
react to hormonal changes that are characteristic for the ovulation period and expand a little. The
small thickening modifies the refraction of the light, resulting in a violet dot on a golden background.
To determine the menstruation period, two indicators are necessary. In the first place, a resin is used
which turns blue at the presence of the smallest trace of blood. The second product is an acid which
turns red at a pH between 4 and 7. These two indicators together give a purple colour, approximately
four hours before the start of the menstruation.
The U.S. Army Soldier Center in Natrick is doing research work on camouflage clothing by examining
two different concepts. Under one concept, soldiers would choose from a database of existing
patterns, such as South American Jungle, that would be replicated on the garment. Other camouflage
researchers at the Tokyo University are examining ways to create clothes with the ability to take digital
images of the surrounding environment and duplicate them then on the clothes. This is referred to as
“Predator” effect [144].
2.2.3.2 Patents published
In US patent 20050074639 the company Unilever patents a method producing a hair covering which
comprises a woven or non woven substrate comprising synthetic or natural materials, which are
impregnated, or coated, or both, with a thermochromic dye. The hair covering of the invention may
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