The color difference of fabrics has always been a headache for the dyeing factory masters. The formula and process are exactly the same. In the end, they will be revised repeatedly due to differences in vats and batches.
01
In fact, whether it is vat difference or batch difference, it is a long-standing problem in the dyeing and finishing industry. There are many factors that affect color difference and it is quite complex. It is fundamental to overcome vat difference and batch difference. The problem cannot be realized and can only be carefully analyzed and controlled. It is possible to control the color difference within the minimum range.
We all know that good colors not only score products, but also increase customers’ desire to buy. For the fabric industry, the raw materials of the fabrics we commonly see, such as polyester, acrylic, vinylon, spandex, etc., are all fibers. If you want to reduce the color difference of the fabric to the minimum, you need to start controlling the color difference at the source of the fabric. .
Because the purity of the color of the fabric is inseparable from the fiber.
The main components of natural fiber are cellulose fiber, moisture, and natural impurities (ash). These components will vary depending on the natural growth environment. , and at the same time, some debris, such as weaving oil, etc., will also be mixed in during the production process. In different raw yarn origins or fabric production companies, these natural impurities and adulterations not only differ in content, but also have different physical and chemical properties. Sometimes even fabrics with the same batch of yarns as raw materials have different effects during dyeing. There are also some differences in performance. If these differences are not handled well, they will directly affect the color of the finished product, resulting in larger color differences.
The effective solution is to strictly control the quality of the weaving process and establish a complete traceability system based on fabric-related data to facilitate timely adjustments to the process formula.
02
The stability of dye additives and processes will also affect the color of the finished product. , these important links need to be strictly controlled. Another very important point is that the color standards need to be unified. Generally, the operation process of a dyeing factory cannot escape the following key steps: Customers send samples → Laboratory samples → Send customers for confirmation → Customers confirm the color → Plan cylinder arrangement → Dyeing The workshop is put into production. During this process, it is necessary to coordinate the color issues of each link. When producing different batches, when it is found that the production time interval of the customer’s products of the same color is long, the laboratory should promptly replicate the sample (i.e. re-sample) , if any large deviation is found, it must be corrected in time.
In the production process, generally customers will specify the △E color difference range. Try to produce the same type of cloth with the same color in the same type of dyeing machine, which can achieve the best results to a large extent. Reduce the occurrence of color difference, of course, this is subject to the actual production conditions of the dyeing factory.
And if the operators can be fixed, the so-called three fixations (fixed personnel, fixed machines, fixed processes), it will be more conducive to the accumulation of experience of the operators. At the same time, human operating errors will naturally be reduced a lot. Most dyeing factories have a consensus on this. Key personnel in key positions have high professional quality requirements and should have business capabilities that combine theory and practice.
03
It is very necessary to control color difference from the source and in every production process, but the premise for us to solve color difference is that How to evaluate color difference.
Maybe you think there is color difference, but your colleagues think there is not. What is the standard for color difference? How to test? This also needs to be considered. There are generally two methods for identifying color difference on the market.
1. Use an international standard color light box: look at the color difference between two pieces of cloth under a specific light source. But this method has a small flaw: the same color looks the same under a certain light box, but it looks different when the light source is changed. Of course, if the customer has already requested which light box light source can be matched, then there is no need to worry.
There are generally two types of color matching light boxes. One is domestic color matching light boxes, such as Qiantongcai color matching light boxes; the other is imported color matching light boxes, such as PANTONE color matching light boxes, X-Rite QC light source light box, etc.;
2. Use a spectrophotometer to measure the color of the fabric itself. It does not rely on the light source and can simulate many colors by itself. kind of light source. Spectrophotometers are very suitable for complex color analysis. Of course, they are also relatively expensive. However, if the color difference measured by a spectrophotometer is small, the color difference seen under any light source will be very small. Nowadays, spectrophotometers are also It is gradually replacing the color matching light box and becoming a commonly used color matching tool in the printing and dyeing industry.
04
What problems do you generally encounter when using a colorimeter? How to solve it?
1: The colorimeter cannot be turned on when it is powered by a battery. What should I do?
1. If this phenomenon occurs, it means that the battery power is insufficient and the colorimeter needs to be powered.;
2. If it still doesn’t work, you can unplug the power adapter, plug in the power adapter again, and check if it can be turned on, or try unplugging and plugging the power adapter several times;
3. If the above method still does not work, replace the battery and try again;
4. If it still does not work, you can contact the supplier where you purchased the colorimeter. Solve the problem through customer service;
2: What should I do if the colorimeter measurement results are abnormal?
1. This situation is generally caused by black and white correction not being performed or black and white correction being inaccurate. Black and white plate correction needs to be performed first.
2. Dirt entering the measuring port will also cause inaccurate measurement. It is best to check before measuring;
3 . Check whether the battery consumption is too low;
4. Check whether the instrument and the test object are stable during measurement, and whether the measuring port is in close contact with the measuring surface;
5. Check whether the measurement object is too thin and leaks light;
6. Check whether the measurement part is mixed color;
Three: What should we pay attention to when using a colorimeter?
1. The colorimeter is a precision measuring instrument. Drastic changes in the external environment of the instrument should be avoided during measurement. For example, flickering of ambient light in the surrounding environment should be avoided during measurement.
2. Generally speaking, colorimeters are not waterproof and must not be used in high humidity environments or water mist.
3. Keep the instrument clean and tidy, avoid water, dust and other liquids, powders or solid foreign matter from entering the measuring aperture and inside the instrument, and avoid impact or collision on the instrument.
4. If the instrument is not used for a long time, the battery should be removed.
5. After using the colorimeter, it should be returned to the instrument storage box for safekeeping.
6. The instrument should be stored in a dry, cool environment. to avoid damage to the instrument.
In the printing and dyeing process, controlling color difference is a complex process. Simply classifying it as a technical or management factor is not objective enough. How to effectively control color difference depends on each printing and dyeing process. Each factory has its own set of experience methods, and the methods are constantly explored. </p
