The printing color effect of pigment printing pastes will vary with the composition of raw materials. In order to control the printing process quality, it is necessary to mix the color of the color paste to meet the specific appearance color requirements. This article brings you the deployment method of pigment printing paste. Interested users may wish to have a look!

Composition and function of pigment printing paste:

The pigment printing pastes used in production have simple types, usually only coatings, adhesives and thickeners. Other additives can be added when there are special requirements.

Paint is a paste made by mixing and grinding pigments, wetting agents, diffusing agents, stabilizers and water in proportion. Paint gives the color of printed fabric, determines the brightness of the color of the product, and affects the sun fastness, climate fastness and sublimation fastness of the design. The basic requirements of printing for paint are:

1. High coloring power and hiding power. Coloring power refers to the amount of color given. The paint with value can print the degree of color intensity, which is one of the main technical indicators of paint. Covering power refers to the ability of the coating to completely cover the printed fabric, which is often expressed by the amount of pigment required for the covered area. The hiding power of paint is affected by the amount of pigment, particle size and other factors, which is another important technical index of paint.

2. High light resistance, heat resistance and climate resistance.

3. Good chemical stability, stability to acid, alkali, oxidant, reductant and dry cleaning agent.

4. Proper density and dispersity ensure that pigment particles do not float or precipitate in the dispersion system.

5. Good sublimation fastness and smoke fading fastness.

Adhesives are molding polymer compounds, also known as adhesives, with an average relative molecular weight of about 100000, of which synthetic polymers are widely used. The common commercial adhesive is a lotion of polymer dispersed in water in a fine state, with a solid content of 30% - 40%. The function of adhesive is to form a transparent film with strong adhesion after molding treatment, and fix the coating on the fabric. Therefore, adhesives affect the hand feel of hardened products, as well as the color fastness of soaping, brushing, dry friction, wet friction and so on.

Thickener plays the role of carrier in pigment printing, making the pigment binder and other additives evenly dispersed and transferred to knitted fabrics. The thickeners used include emulsion paste and synthetic thickener. The main problem of synthetic thickener in use is that it is not resistant to electrolytes, which will dilute the printing paste, reduce the viscosity, and infiltrate the printed pattern, affecting the printing effect. Synthetic thickeners can be used in the production of full pigment printing. It should be noted that there are electrolytes in the printing paste of anti discharge paint.

How to prepare pigment printing paste?

Due to the different composition of pigment printing pastes, the color effect of pigment printing will be very different. In order to control the quality of pigment printing pastes, it is necessary to strictly control the mixing process of pastes. At present, the color paste can be prepared manually or through the automatic color paste preparation system. The automatic color paste mixing system is composed of computer, color matching software and color measuring and matching system. Through the application of automatic color paste blending system, the printing color matching can be digitalized, accurate and reliable, and the production efficiency is high, which is the development direction of pigment printing color paste blending.

Mixing method of color paste:

1. Computer color matching

In the computer color measuring and matching system, the basic database of printing process should be established first, that is, small samples of each dye should be printed according to different concentrations, and then the small samples of printing should be tested with a colorimeter, which should be stored in the computer as basic data for providing color matching formulas. The future sample is tested on the colorimeter as a standard sample. The testing and matching system looks for the formula in the database according to the test results, prints and proofs according to this party, and then tests the color difference between the tested sample and the standard sample. If the color difference is not within the allowable range, the testing and matching system will correct and adjust it, proofing and measuring the color difference again until the color difference is within the allowable range. At this time, an appropriate amount of color matching will be provided to the color matching system.

2. Automatic slurry mixing

The paste mixing system is a very important part of the whole automatic paste mixing system. It can be used in combination with the color measuring and matching system or alone. That is, the color paste can be modulated by measuring and matching the color system or inputting the required process formula through the keyboard. The system can be configured with dozens of high-level barrels. Before slurry preparation, the original paste, dye solution and auxiliary solution should be pumped into the corresponding high-level barrel, and compressed air should be introduced to maintain uniformity. After the measurement and color matching system provides an appropriate amount of slurry mixing, the slurry mixing computer can start to work. The electronic scale automatically moves from left to right along the track, adding an appropriate amount of raw paste, dyes, additives and water. All feeding data can be displayed on the display screen of the computer console, and you can also print out an appropriate amount of slurry mixing with a printer. After discharging, the color slurry is obtained by stirring with a mixer.

Article source: Guangdong Printing Materialshttp://www.jmyiben.com