COLOR PROPERTIES
Color is a very complex function.
The white color is a combination of many individual colors or wave length
of electromagnetic radiation. The distribution of intensity of these wave-length
is known as specter and varies significantly - the sunlight, fluorescent
light and many other sources of light.
Any color visualized by someone, depends on the individual vision or on
the atmosphere in which the color is observed.
Visual Color Comparison
There are many aspects which should be avoided when comparing samples
visually such as:
1-Dicroism
It's an apparent alteration of color when the visual direction is changed.
It occurs more in woven than in threads, but it may affect the color approval
of the thread.
2-Matamerism
It's a color alteration that happens when light conditions are changed.
For example, if we observe a green object during daylight, a certain quantity
of light is reflected as green. If we observe the same object under a
fluorescent light, rich in red and blue, but deficient in wave-length
of green and yellow, then there is less available light to be reflected
so the object will appear to have a different color and will show a lack
of color continuity.
This is a great problem when comparing two samples by daylight which may
not alter their color gradually under artificial light. This is because
some color mixtures have different absorption characteristics and we call
"Metamerism do iluminante".
When two independent observes don't see a color in the same way we call
it "observer metamerism".
When a color seems different according to the different vision angle we
call it "geometric metamorism".
When we produce a color in Valfios, a color mixture is examined carefully
to the diminish the metamorism.
3-Conditions of the Visual Analysis
A color sample may be analyzed on different surfaces and so the observer
can be see alterations on the color of the sample, this effect is called
simultaneous contrast.
The visual comparison of the colors must be done in standard conditions
that is under a standard light of comparison in a standard cabin of visual
analysis (light box).
4-Variations according to the Standard
Thread surface characteristics can influence the visual comparison and
it can produce disagreements between the annalists debates.
Anyway the color selection done by the human eye is not always stable
(age and sex of the observer we variable aspects. For better criticism
the selected colors can be analyzed when sewed to the cloth.
When the thread goes through the sewing machine, it's tone can be affected,
because it's surface is altered as well as it's distorted balance. The
sewing in parts of different densities can cause tone differences. The
lubrification can also affect the tone.
5-Color Measure
All the color commercialized by Valfios, are approved by the photo meter
specter color reading compared with the pattern sample.
The medium photo specter measures and registers automatically the color
specter of a sample comparing with the pattern.
Besides, this reading all colors are visually compared in a light box,
and all this work is realized to guarantee the color continuity.
6-Steadiness Towards Cleaning and Color Alteration
After choosing one of the sewing line suitable to the material that's
going to be sewn or to use as contrast, it's important that the thread
color stays firm during the useful life of the material.
That's why tests of washing steadiness of the sewing line must be controlled
(color alterations and stains).
There is a catastrophe whenever a piece of clothes stains, owed to embroidery
or of a white cloth sewed with a dark thread of bad steadiness.
A sewing thread must remain with the same cloth color after a simple wash
or a dry cleaning.
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