Colors have different definitions in terms of being tangible and intangible, as well as the place of their appearance, from which we will limit ourselves to two general definitions and we will refer to more detailed definitions in the section of different types of colors.
Definition of physical color
This color is the feeling of the eye against the reflection of light on the object, and in other words, it is the spectral energy distribution of a rhombus that is reflected from a surface.
Definition of material color
Material color is any type of natural or artificial colorant that is used in coloring objects and bodies.
The main physical colors are seven colors, which are red, orange, yellow, green, blue, indigo and violet. White color is a set of said colors. Based on the wave theory of light, it has been proven that different physical colors are lights with different wavelengths; For example, dark red light with a wavelength equal to 0.8 microns has the highest wavelength and violet light with a wavelength of 0.4 microns has the lowest wavelength, and the wavelength of other colors is a wavelength between these two colors. It should be remembered that these colors change in a connected manner so that the demarcation of two colors is not clear (interviewer, first volume, under the combination of words of physical colors).
Material color is any type of natural or artificial colorant that is used in coloring objects and bodies. According to most experts in the dyeing industry, there are only three main colors in nature. These three colors are: Red, blue and yellow colors. Other colors are prepared from the combination of two or three main colors. Black color is a mixture of these three primary colors. By combining two main colors and changing their amount and behavior, many colors are made; For example, from the mixing of red and blue, several thousand pale and rich red and blue colors are created. By mixing red with yellow, several lemon-like and golden colors can be obtained, or by mixing yellow and blue, a wide range of pale or rich green colors can be obtained. It produced many such as olive, brown, etc., which the people involved in the traditional dyeing industry of Iran, including Kashan, have considerable knowledge of most of the mentioned codes.
Material colors are also divided into two categories according to their quality and method of preparation:
The oldest chemical dye was made in 1838 by Sir William Perkin, a famous English chemist, and her colleagues. Most chemical dyes are obtained from the distillation of coal. The chemical dyeing industry has made significant progress until today, and the number and variety of chemical dyes and the techniques and methods used in its production are beyond the scope of this discussion, and addressing it will lead to the main issue of natural color and Dyeing with them is to get away.
2- Natural colors
Many types of these dyes and effective materials in dyeing with them mostly exist in nature. These dyes play a significant role in the traditional dyeing industry of Iran. Roles are divided into three categories by origin:
2-1. Plant or (vegetable) coloring matter
2-1. Plant or (vegetable) coloring matter Plant dyes are more important and reliable compared to other dyes. The most prominent plant dyes known in the dyeing industry are: nil nil, henna hana, joft pair, runas runas, esperak spray, baqam red baqam, mo leaf, kol barqekul leaf, wij barge leaf, cucumber leaf, chrysanthemum leaf, forest raspberry, sumac, barberry, turmeric, saffron, bark Walnut, pomegranate peel, pistachio peel, onion peel, hazelnut peel, marigold, sparrow tongue flower, marshmallow, sunflower flower, pomegranate flower, evening primrose, goleskuti flower, gandal and many other plants.
The pigment part in different plants may be flowers, stems, branches or roots. Today, due to the progress of the dyeing industry and the common use of chemical dyes, most plants are not used; Except for a few that will be explained about each one.
2-2. Animal dyes
These materials, as their name implies; There are materials that are somehow obtained from animals or insects, and the most important one is “red seed”. Due to its important role in the traditional dyeing industry, this material will be explained in a separate topic.
This material is a type of marine mollusk. Its most famous type is pink purple, which is attributed to the city of “Tur” in Lebanon, and it has not been used in dyeing industries for many years.
2-3. Mineral dyes
These materials are extracted from mines in pure or impure form.
Its oldest type is “Gol Okhri” which has been extracted and consumed in Iran since prehistoric times, and the best type of it that is world famous is “Gol Okhri” of Hormuz Island in the Persian Gulf. “Prussian blue” is another mineral color that exists in crystalline and multifaceted form and is used in the preparation of painting and dyeing colors. The chemical name of this color is “ferric and cyanur ferric panasim”.
Color resistance against various chemical factors, abrasion and light is called “color stability” and the amount of this resistance against the mentioned factors; Is different. Among the effective factors in carpet cream color, three factors are more important, which are: “Light”, “washing” and “rubbing”. The best type of carpet in terms of coloring is the resistance of the colors used in it against the three mentioned factors; be more and in other words have a higher degree of stability. The stability of colors against different factors has been graded from 1 to 8 and this is an international agreement. The degree of carpet color stability against light should not be less than 5 and against other factors less than 4; And otherwise, the prepared carpet will not be of the required quality. Also, the sum of color fastness scores of a quality carpet should not be less than 27. For fabric dyeing in the textile industry, the dye used (in terms of stability) is selected according to the type of fabric used. For example, more light-stable color is used for fabrics that are more exposed to light. (such as curtains) and paint with better abrasion resistance are used for fabrics that are exposed to more friction during use. (such as rumbly fabric and…)
Based on ancient works and objects obtained from archaeological excavations, in Iran, from about five to six thousand years ago, painted and colored earthenware was used as means of life, and samples of these vessels are kept in most of the world’s famous museums. Among them, there is an engraved pottery mug from Susa dating from 3,500 years BC in the Louvre Museum in France, or an engraved pottery tallow burner from Silk Kashan dating from the first millennium BC in the Nelson Gallery in Kansas City, USA. The existence of these objects proves the ancient familiarity of the people of this land with color and painting. Among other signs of familiarity of Iranians with color and coloring, the following can be mentioned: The use of metal shavings and its preparation method in the second (copper age), third period (bronze age) and fourth period (iron age) of Iranian history, the use of copper rust in the preparation of turquoise color or flint and lead In the preparation of yellow color and the existence of modifications such as “Iranian red”, “Iranian blue” and “Iranian glaze” which are mentioned in most of the articles and writings related to the art of pottery, some researchers believe that the colors used in The patterns on the dark colored pottery are made entirely of manganese. In addition, there is a certain connection between the ancient pottery samples and the modern pottery of the potters of “Kalpurgan” village (of Saravan districts in Sistan and Baluchistan) and this similarity is due to the presence of manganese which is extracted from the nearby mountains of this village. The oldest dyestuff that still plays a significant role in the dyeing industry (both traditional and new) is “indigo”. The discovery and use of indigo dates back to about four thousand years ago.