1、 Preparation before tinting

1.1 physiological preparation

People's color matching accuracy is much higher when they have a good rest and full of energy than when they are tired; When a color is visually inspected, the accuracy of the first visual inspection is higher than that of repeated visual inspection for a long time. Therefore, in a good mental state, focusing on the results measured in a short time is the physiological premise of efficient color matching.

1.2 dye selection

According to the customer's samples, we should first understand the customer's requirements for color. If the customer requires a variety of light source color matching, it is necessary to use computer color measurement to select dyes, so as to avoid or reduce the phenomenon of the same color and different spectrum between the small sample and the customer sample (hereinafter referred to as the customer sample). Understand the fastness performance of the selected dyes and the fastness requirements of customers; Also understand the ease of operation, stability and safety of the selected dyes. Finally, we need to consider minimizing costs and reducing emissions.

2、 Tinting of primary colors

3、 Primary color matching is a common method, and many customer samples can be dyed with three primary colors. If the properties of the three primary colors used in customer samples are similar or consistent with the dyes used in proofing, the same CHNSpec is very small or there is no same CHNSpec phenomenon. General dye manufacturers will recommend three primary color combinations with different dyeing depths according to the directness, migration, diffusion, promotion, reactivity and other indicators of each dye. For example, Clariant acid dyes have three primary colors: Yellow e2rl or e4rl, red ebnl and blue ebgl; Three primary colors: yellown3rl, red n2rbl and blue nbln; Medium dark economy ternary: Yellow n3rl, rubine n5bl, blue NRL or NRBL. There are generally two ways to get the first prescription after selecting dyes: first, use computers and software to automatically find the close first prescription from the database previously input into the computer; Or according to the color data of different concentrations of each single dye input into the computer (also known as monochrome data), the computer calculates the first prescription. Second, according to the retained historical sample card. Many experienced colorists usually accumulate a lot of historical sample cards. After the guest samples come, they can look for the close historical sample cards and get the first prescription after correction. The following explains the color matching method of three primary colors on the processing mode of continuous pad dyeing.

2.1 depth before hue

Human eyes are very sensitive to the hue of the three elements of color, followed by purity and dullness to lightness. The color light of the same dye will change at different concentrations, especially in darker colors, such as Clariant navynrbl. The darker the blue, the redder the color light. Moreover, the dye reaches saturation after dyeing to a certain depth. Even if the amount of dye is increased, the color yield will not increase. In this way, if the hue is the same and the depth is different, increasing or reducing the dyes in the same proportion often leads to the change of hue and color light. Therefore, if we first adjust the depth on the basis of ensuring that the hue is close, and then adjust the hue, so that the increase or decrease of the dye used in the later adjustment is very small, the human eye can not feel the change of depth, but the change of hue is clearly reflected. Generally speaking, with the increase of the single depth of bright red, the more yellow its color light is; With the increase of single depth of jujube red, the more blue and black its color light is; When the single depth of sapphire blue increases, the more red its color light is; With the increase of black single depth, the more red and yellow the color light is; With the increase of the single depth of coffee color, the bluer the color light is. Mastering the variation law of color light with depth can also adjust the depth and hue together, and the color matching efficiency can be higher.

2.2 percentage addition and subtraction algorithm

Percentage addition and subtraction is the basic algorithm in color matching. For example, when the mass concentration of a dye used for proofing is 1 g / L, it is considered that it should be increased to 1.1 g / L by visual inspection or computer color measurement, and the algorithm should be increased by 10%.

2.3 exchange method

The exchange method is mostly used when the color mixing action is large. For example, when 0.5 g / L of a dye is used for proofing, it is considered to be increased to 1 g / L after the customer sample, that is, it is increased by 100%. At this time, the customer sample can be used in turn to the small sample to see whether it is necessary to subtract 50% from 1 g / L to the color of the small sample. In this way, the accuracy of color matching can be verified and corrected.

2.4 pinch method

The pinch method is to find the location of the guest sample from multiple samples. For example, the dye dosage of sample a is 0.8 g / L and that of sample B is 1.1 g / L. It is found that sample a is shallow and sample B is deep. At this time, the guest sample is placed between sample a and sample B. visually, the distance difference between the guest sample and the color depth of sample a is twice that of sample B. in this way, the amount of dye is about 1 g / L.

2.5 step by step

The step-by-step method is to deduce the position of the customer sample from multiple small samples. For example, the amount of dye used in sample a is 0.7 g / L, and the amount of dye used in sample B is 0.9 g / L, which is not enough for customer samples, a and B. visually, the amount to be increased from sample B to customer sample a is half that of sample a to sample B. at this time, the amount of dye used is: 0.9 g / L + (0.9-0.7) / 2 g / L = 1 g / L.

2.6 absolute law

Absolute method is based on the full understanding and clear memory of monochrome data. It is mostly used when a new dye needs to be added in color matching. This dye has not been used in previous color matching. Of course, the percentage addition and subtraction method cannot be used. If the newly added amount of dye has a large proportion of the main dye, the computer should be used to measure the color and select the dye to prevent the same color from different spectrum. For example, the small sample has poor red light compared with the guest sample. At this time, visually measuring the color depth of a red dye of 0.1 g / l can fill the gap between the small sample and the guest sample, that is, add 0.1g/l of the red dye to the color matching prescription.

2.7 relative method

The relative method is mostly used in color matching. When a new dye needs to be added, the premise is to have sufficient memory and understanding of the color light, force and lifting force of each dye. For example, if the amount of dye a (200% force) in the small sample formula is 10 g / L and the amount of dye B is 1 g / L (100% force), the main dye is dye A. It is necessary to add dye C (100% force) between the small sample and the customer sample by visual inspection, and the amount of dye C is considered to be 2% of the main dye a under the standard force. At this time, the amount of dye C in the prescription is 10 g / L × 2 % ×  （100 %/200 %） =0.1 g/L。 This method is generally used in conjunction with the absolute method to improve the accuracy of toner prescription.

2.8 computer color matching

When the dyeing process conditions are fixed and controllable and the input data system is correct, the computer color matching has high accuracy and stability. However, in practice, especially in workshop production, the effectiveness of computer will be greatly affected by various uncontrollable factors. Therefore, on the one hand, we should constantly strengthen and improve the controllability of production conditions, on the other hand, we should strive to reduce the randomness of human operation, so as to really give full play to the role of computer color matching.

3、 Non trichromatic tinting

Restricted by some conditions for selecting dyes, such as to improve the stability of mass production; Or the color light of a certain dye is close to that of the customer sample, and only a small amount of other dyes need to be added to adjust to achieve the customer sample color; Or customers have high requirements for the same color and different spectrum and cannot do it with three primary colors. At this time, non primary color matching or partial non primary color matching will be selected. Such as bright red + orange + green, Yellow + Green + gray, dark brown + yellow brown + black, etc. According to the subtraction principle of color matching, the color light of non trichromatic dyes can be understood as the combination of multiple trichromatic dyes, and in practice, the color light of non trichromatic dyes can generally be combined by multiple trichromatic dyes. For example, bright red can be combined by about 20% of trichromatic yellow and about 80% of trichromatic red. The trichromatic dye and the trichromatic dye can be used as the basis for the production of the trichromatic dye, because the trichromatic dye and the trichromatic dye can be used to enhance the trichromatic dye's trichromatic dye's trichromatic dye's trichromatic dye's trichromatic dye's trichromatic dye's trichromatic dye and trichromatic dye's trichromatic dye's trichromatic dye's trichromatic dye's trichromatic dye's trichromatic dye's trichromatic dye. After analyzing the color and light components of non trichromatic dyes, you can color them according to the color matching method of trichromatic dyes.