01 Dye strength
Dye strength (strength) is based on a certain concentration of dye. , the standard dye strength is 100%. If the dye is twice as strong as the standard dye. Then its intensity is 200%, and so on, so the intensity of a dye is usually a relative number.
Dye strength, also called dye strength (Strength), is a semi-quantitative index that refers to the relative coloring intensity of the sample dye compared with the dyeing depth of the standard dye. It is an indicator of the dye product. An important indicator of coloring ability. For a specific dye, the dye factory selects a specified dye sample as the standard; dyes each batch of dye products under certain conditions and compares it with the color depth of the standard dye; based on the amount required to dye the same color depth, calculate The strength of each batch of dye product. Generally, printing and dyeing factories must also inspect the strength of each batch of purchased dyes themselves.
02 Dye compatibility
During the dyeing process, the dye The consistency of fiber dyeing rate is called dye compatibility.
The dyeing rate of each dye in the combination on the fiber is the same or similar, so that the hue of the yarn and the concentration ratio of the various dyes in the dye liquor remain unchanged. This behavior is called The compatibility is good, and vice versa.
High-temperature disperse dyes usually cannot be matched with low-temperature disperse dyes, while medium-temperature disperse dyes can be matched with both high-temperature and low-temperature disperse dyes.
03 How to determine dye compatibility
1. Multiple tests Method
Make the three dyes to be selected into 4 to 6 dye baths of the same concentration according to a certain concentration ratio, and carry out dyeing according to the determined process. Samples were taken out at different fixation times, and each sample was post-processed in the same way.
This method is based on the view that if the combined dyes have the same dyeing performance, the color light of dyeing at different times should be the same or similar, that is, the color light of each sample should not change too much with time. Variety.
Judgment method: Compare the color difference between samples. If there is only a difference in shade between before and after and no color change, it can be considered to have good compatibility; if the color light within a certain period of time has The difference can be considered as the compatibility is good if the process conditions are well controlled; if the difference between before and after is large, or the color and light change has no certain trend, the compatibility is considered to be poor.
The comparison of compatibility between different combinations of dyes depends on the comparison of the color differences between the two sets of samples.
The advantage is: the biggest advantage is that it directly reflects the color change during the dyeing process, and the experimental process can be completely based on the production process. Simple and easy. At the same time, this method can also be used in the production process.
The disadvantage is: the design of the experiment and the evaluation of the results require a certain amount of experience.
2. Two-sample step-by-step staining method
Will be selected The three dyes are mixed into a dye bath according to a certain concentration ratio. Take two pieces of fabric A and B of the same weight and add electrolyte to the dye bath. Add A first, and then add B 15 minutes later. After dyeing for about 35 minutes, add alkali to fix the color. Use the same method for post-processing.
This method is based on the understanding that the migration properties of the three dyes play a large role in color matching. If the dye migration properties are good or the dye migration properties of the three dyes are similar, they generally have good compatibility. Therefore, the compatibility of dyes can be inferred from the comparison of dye migration properties.
Judgment method:
If the color light and depth of A and B are exactly the same, the combined dye has excellent dye migration properties and its compatibility is particularly good;
If A and B have the same color light but different depths, it means that the dye combination has similar dye migration properties, but the dye migration rate is poor.
The greater the difference between the shades of A and B, the worse the dye migration and the poorer the compatibility of the dyes.
If A and B have different shades and different shades, it means that the dye combination has poor and inconsistent dye transfer properties, and the compatibility of the dyes is also very poor.
If you need to evaluate two groups of dye combinations, you only need to compare the differences between the two groups A and B. That is, the one with the smallest difference has good compatibility.
04 Laboratory suction material
1. Dye dosage calculation formula
Dye dosage (ml) = dye formula x yarn weight x dye concentration/100
For example:
Dye formula: 0.2% (on fabric weight o.w.f)
Yarn weight: 5 grams
Dye Concentration: 1/100
Rule: dye dosage=0.2x5x100/100=1ml
2. Calculation of auxiliary dosage
Auxiliary dosage (solid g) = auxiliary formula x yarn weight x water ratio/1000
Auxiliary dosage (water agent ml) = auxiliary formula x yarn weight x water ratio x auxiliary concentration/1000
For example: auxiliary formula: 40g/l
Yarn weight: 5g
Water ratio: 1/10
Auxiliary concentration: 1/10
Rule: Additive dosage (solid g) = 40x5x10/1000=2g
Additive dosage (water ml) = 40x5x10x10/1000= 20ml
Water amount calculation formula: water amount = yarn weight x water ratio x dye amount – auxiliary amount (water agent)
05 Calculations related to color mixing and dyeing production
1. Calculations related to dyeing and proofing prescriptions
Calculation formula
(1) Calculation of dye liquor volume requirement during dip dyeing: V=m×f
Formula Medium: V—-The volume of dye solution required for dyeing, mL or L
m—-The mass of the dyeing sample, g or kg;
f—–Dyeing bath ratio.
2. Calculation of dye mother liquor volume requirement
V=m×C/C. ×10³
In the formula: V—-So�Volume of dye mother liquor, mL;
m — mass of dyeing sample, g;
C. —-Dye mother liquor concentration, g/L;
(3) Calculation of additive requirements;
V=C ×V×10³
In the formula: m—the mass of the required additives, g;
C— -Auxiliary concentration, g/L
V—Dye liquor volume, mL
Example
Example 1: 2g of fabric, liquor ratio is 1:50, dye concentration is 0.5% (owf), dye-accelerating salt sodium sulfate concentration is 5g/L.
Question: (1) How many mL of 2g/L dye stock solution should be absorbed?
(2) How many grams of sodium sulfate are weighed?
(3) How many mL of water should be added?
Solution:
According to the liquor ratio, the total volume of the prepared dye solution is: 50×2=100mL
(1) Suppose the volume of dye mother liquor absorbed is V, then:
Fabric mass (g) × 0.5% = dye mother liquor concentration (g/ L) × V (mL) × 10﹣³
V=2×0.5%/2×10³=5 (mL)
(2) Weigh the mass of sodium sulfate:
Concentration of dye-promoting salt × total volume of dye liquor = 5×100×10﹣³=0.5
(3) The volume of water required to prepare the dye solution is: 100-5=95mL
Example 2: Absorb 10mL of 2g/L dye stock solution and dye 2g Fabric, liquor ratio is 1:50, what is the concentration of dye at this time?
Solution:
Dye concentration = dye mother liquor concentration × V × 10-³/fabric quality × 100%
2×10×10﹣³/2×100%=1%
06 Addition and subtraction in color mixing
Addition and subtraction are color mixing terms in printing and dyeing production. In the production of dyeing proofing, when comparing the dyeing sample with the original sample to reflect the difference in color shades between the two, it is usually expressed by how many percent darker or lighter. When adjusting colors, if the dyed sample is darker than the original, you need to adjust the color by reducing the dye concentration; conversely, if the dyed sample is lighter than the original, you need to increase the dye concentration and increase the amount of dye. For example, if the dyed sample is 20% darker than the original, the color adjustment will be reduced by 20%; conversely, the corresponding percentage needs to be increased. One becomes 10%, two becomes 20%, and so on.
1. Calculation formula
(1) If you need to increase the concentration: concentration after deepening = original prescription concentration × (1 + percent )
(2) If the concentration needs to be reduced: reduced concentration = original prescription concentration × (1 – fraction)
2 , Example
Example 1: During dip dyeing, a dyed sample was dyed using reactive red 3BS with a concentration of 1.2%. Comparing the dyed sample with the original sample, it was found that it was 30% darker than the original sample. Calculate the adjusted activity What should be the concentration of Red 3BS?
Calculation: Adjusted active red 3BS concentration = 1.2% × (1-30%) = 0.84%
Example 2: During dip dyeing, the concentration of reactive yellow 3RS used in a dyeing sample was 1.2%. Comparing the dyed sample with the original sample, it was found that it was 40% lighter than the original sample. Calculate what the concentration of reactive yellow 3RS should be after adjustment?
Calculation: Adjusted reactive red 3RS concentration = 1.2% × (1 + 40%) = 1.68%
3. Dyeing production in progress Basic calculation
Example 1: 1000 meters of fabric, mass per meter is 80g, liquor ratio is 1:20, dye A concentration is 1%, dye B concentration is 0.2%, salt The concentration is 30g/L. Question: What is the weight of the fabric, the amount of dye liquor, weigh the dye and salt, and the amount of water added?
Solution:
The weight of the fabric is: 80×1000×10﹣³=80kg
The total volume of the dye solution is: 20×80=1600L
Weigh dye A: 80×1%=0.8gk
Weigh dye B: 80×0.2%=0.16kg
Weigh salt: 30×1600×10﹣³=48kg
Add water: 1600L</p
