Colour Science,Colours in Cosmetics and Colour Cosmetics



Colour wheel : visual representation of colors arranged according to their chromatic relationship

Primary, secondary and tertiary colours

Complementary Colors: Those colors are located opposite t o each other

Analogous Colors: Those colors located close together on a color wheel

Absorption and reflection of different wavelengths of light generates colour. These wavelengths can be measured by spectrophotometer or colorimeter

Principle of spectrophotometer: It measures light energy absorbed or reflected by a material. Multiple sensor receives transmitted or reflected light by the help of microprocessor. If the output is expressed as numerical data linked to absorbance/reflectance of colours they are called colorimeters. The data from colorimeter can be evaluated where in human eye can not differentiate.

Eye response to light stimulus: Light, no matter how complex its composition of wavelengths, is reduced to three color components by the eye.

For each location in the visual field, the three types of cones yield three signals based on the extent to which each is stimulated. These values are sometimes called tristimulus values.

Color expression: Phenomenon of trichromacy - Any color stimulus can be matched by a mixture of three primary stimuli, so long as none of the three can be matched by a mixture of the other two.
Color matching can be expressed as: C (tristimulus value) =RR +GG+BB
Equal stimulus proportions of all three primaries create white:
1 Red+ 1 Blue + 1 Green = 1White
Equal stimulus proportions of two primary colors create a secondary color.

1 Red+1 Blue=Magenta
1 Blue+1 Green=Cyan
1 Green+1 Red=Yellow

Spectral sensitivity of Human eye: There are three types of cones on the basis of wavelength they absorb. Short, Medium & Long.

Sensitivity of eyes: Three white curves indicate responses of three types of cones for color stimulus red (564) blue (437)and green (533). Black curve indicate sensitivity of sensory rods at night.

colour communication system: Lab is based on continuum of color wheel and expression of lightness and darkness on vertical plane. There are several other adaptations of Lab colour matching system like Munsel colour wheel. Other example is Pantone color chart.

Infinite number of colours surround us in our daily life. We Take colour pretty much granted but influence of colours is enormous. It helps to understand taste in food, influence our purchase decisions. It has lasting impression. It distinguishes beauty, helps in Likes & Dislikes. Integrity of colour within environment features unique code and conduct in animals & insects. Species have developed camouflaging colours to improve survival. Some species change colour to different situation and different season. Primitive tribes used Colour makeup has been used to enhance their predator instincts, frighten tribal enemies, attracting and capturing, for match and mate. Cosmetic Science is a science which deals in health and good appearance of Skin and its appendages. Impressions of Beauty are intrinsically linked to colour appearance as Healthy skin/fair skin/Flawless skin, Jet black/Blonde hair, Bold eyes, Blushing cheeks, Luscious lips & elegant nails.

Emotions and colours are strongly linked - Colour must appeal to emotional makeup of customer at the specific moment of purchasing. Predicting colour trends are both art and science. Societal indicators are used for upcoming colour trends. Fashion shows in Europe and USA consist of fabrics, prints, textures, garment design, accessories, hair & nail makeup etc. Artistic directors put together some of the industry’s hottest colour and makeup collection. Colorants has long history. Documented in Egyptian Papyri and found in tombs 5000 year BC. are Henna, Kohl, Carmine, saffron, copper & antimony compounds. Use of colours in foods & wines started as early as 1860.

First synthetic organic color was discovered in 1856. Proliferation of use of colors in foods was recognized as threat. Now we should understand Colour nomenclature. US FDA took up monumental task of assessment of safety of nearly 700 coal tar colors and created three categories of safe colors: FDC colors, D&C colors, and Ext D&C colors. Colours are given numbers like FDC blue 1, D&C red 3 or Ext D&C green 4. In European classification EC nomenclature Number given like E 102. In many countries colours are listed as Colour index numbers. CI numbers are allocated by Society of dyers and colourists UK. Scheme covers colours used in food, personal care products, cosmetics, house hold products and fabric dyeing. Example: Tartarazine CI no 19140 Erythrosine CI No.45430.



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