关于颜色_about+color.pdf

Colors, Paints & Pigments
• Color introduction
• Groups of paints and their applications
• Pigments, Preparations, Dyes
• Properties of pigments
• Pigments used in paints
•Value in use
•Paint manufacture
•Further Pigment properties and effects
Literature:
Chapman & Hall : Surface Coating, raw materials and their usage
GPA Turner : Introduction to Paint Chemistry and principles of technology.
A. Wlym : Paint Training Manual
Ciba Specialty Chemicals
BL Coatings
MC Deco
Why color ?
• No light −−> no color
• The three following elements are necessary to perceive color:
• light emitting energy
• object absorb a part of energy and re-emitting the rest as energy
• vision allows us to perceive color
Ciba Specialty Chemicals
BL Coatings
MC Deco
Energy transfromation to Color
Light = Energy = Waves
Light
source
A part of energy is The retina receives the light reflected by the object.
absorbed, the rest is The cones of various sizes collect information's
reflected which are transmitted to the brain by the optic
nerve.
Cones
object Eye brain
Ciba Specialty Chemicals
BL Coatings
MC Deco
What is color ?
• Color is a matter of perception and is a subjective interpretation
• A color expression often means ten different colors to ten different people
• A variety of conditions affect how a color looks
- light source: called illuminant (daylight, tungsten or fluorescent light, etc....)
- observer: the sensitivity of each individual’s eyes are slightly different
- size of the pieces: colors covering a large area tend to appear brighter and
more vivid than colors covering a smaller area.
- background: a paint applied over a white substrate appears brighter than if it
is applied over a black substrate. This is referred to as contrast.
- angle viewing: looking at a car painted in a metallic shade from a different
angle, the color appear brighter or darker. This is called flop
Ciba Specialty Ch