Before we learn the method of paint color matching, we should first know some common sense about color. The colors of objects in nature are ever-changing. The reason why people can see the color of an object is because the light of the luminous body shines on the object, the light radiates on the object, and the radiant energy of the light acts on the eyes. The color of a non-luminous object only appears when it is illuminated by light, and the color of the object is determined by the reflection and absorption of light on the object. An object appears green in sunlight because it mainly reflects the wavelengths in the green range of white light, while other parts of the spectrum are absorbed by it. If you look at this object under a sodium lamp, you can't see that it is green because there is no green component in the sodium lamp that can be reflected by it. Here, we can see that the visible color of the object changes with the composition of the illumination spectrum. If an object completely reflects the incident light, it looks white to us, and if it completely absorbs the light projected on it, it looks black.
Colors can be divided into achromatic colors and colored colors. Achromatic means that there are different shadows between black, white and gray. Achromatic reflectance of black and white series represents the lightness of the object. The higher the reflectivity, the closer to white, and the lower the reflectivity, the closer to black. Color system refers to all colors except white and black series. Different wavelengths of the spectrum are visually represented as tones of various colors, such as red, orange, yellow, green, cyan and purple. To explain a certain color clearly, we must consider three basic attributes of color, namely hue, saturation and lightness, which form a unified overall effect visually. Tone refers to which wavelength is dominant in the light reflected by an object. Different wavelengths produce different color feelings, and hue is the basic feature that determines the nature of color. The saturation of color refers to the brightness of color. Hue, lightness and saturation are the three basic attributes of color, while achromatic color only has the difference of lightness, but not hue and saturation.
Mixed colors of paints, pigments, dyes, etc. Follow the principle of subtraction and mixing. The three primary colors are yellow, cyan and purple, and their complementary colors are blue, red and green. The so-called complementary color means that two colors of light are mixed in a certain proportion to get white light. The complementary color of red is cyan, the complementary color of yellow is blue, and the complementary color of green is purple. The results of subtraction mixing are summarized as follows:
Yellow = white and blue
Purple = white green
Cyan = white-red
Yellow+purple = white-blue-green = red
Yellow+cyan = white-blue-red = green
Purple+cyan = white-green-red = blue.
Yellow+purple+cyan = white-blue-green-red = black.
These relationships show that the brightness of the color obtained after mixing decreases when the pigments are added in turn.
Paint color matching technology mainly includes solid paint color matching, transparent paint color matching, metallic paint color matching and so on. Usually, before drawing up the color matching formula, we should analyze it according to the color template or the color of an object. First of all, we should understand the hue range, which is composed of several colors, which is the main color and which is the auxiliary color, what is the relationship between colors and how much each color accounts for. Then, according to our experience, we preliminarily draw up the color matching formula, and then debug the samples. When mixing colors, the main color should be added first. Then the color with strong coloring power is added slowly and intermittently, and the mixture is continuously stirred. Observe the color change at any time, sample, wipe, brush, spray or stick it on a clean sample, and compare it with the original sample after the color is stable. In the whole process of color matching, we must master the principle of "from shallow to deep". It can be seen from the principle of subtractive method that if the sample is compared with the standard board, red can be subtractive method or cyan method, green can be green method, and blue can be purple method, and vice versa, because yellow, cyan, purple and blue, red and green are complementary colors, but the mixing of these pigments will lead to the decrease of brightness, and the brightness of mixed colors can be adjusted by black and white.
At present, paint manufacturers generally have black, white, red, green, blue, yellow, cyan, purple and other color pastes or masterbatch for color matching. In the process of color matching of solid paint, the color matching method of adding 5% high concentration color paste to white base in light color area and strengthening quantitative color paste with varnish in dark color area is adopted. However, some transparent pigment paste or dye solution is selected for the color matching of transparent color, and the color change of transparent color is also affected by the thickness of coating and substrate, so the actual color matching should be compared with the specified thickness and substrate. The color matching of metallic paint should not only follow the basic principles of pigment blending, but also consider the influence of self-luminous metallic pigments on color, which is relatively complicated. Understand the basic knowledge of paint color matching, study hard and practice more at work, and you will soon master this technology.
Master the theory and then connect with practice. The key thing you need to understand is that the characteristics of a brand masterbatch are different. First align the imported paint color. Nowadays, the color of automobile paint is becoming more and more difficult to adjust, and the formula given by the manufacturer needs fine tuning. Individual stores can only adjust it quite simply, some of them change color and have a big contrast before and after, so they have to install the formula given by the manufacturer. Of course, we also need to calibrate it. The most important thing is to master the characteristics of masterbatch, such as PP.