Color Masterbatch Production Process
Color Masterbatch?Also known as color seed, it is a new type of colorant for polymer materials, also known as pigment preparation. It is composed of three basic elements: pigment or dye, carrier and additive. It is an aggregate obtained by uniformly loading an extraordinary amount of pigment or dye in the resin, which can be called pigment concentrate, so its coloring power is higher than the pigment itself. In short, masterbatch is an aggregate obtained by uniformly loading an extraordinary amount of pigment or dye in the resin.
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Before color matching, you must understand the purpose of the product, whether the material used is PP, PE or PET, ABS, etc., and then start analyzing the color matching based on the color of the plastic product.
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1.?According to the purpose of the plastic product, determine the application environment and requirements of the product, the application environment temperature, and then consider the temperature of the masterbatch during processing and use based on these factors to match the color.
2.?Color matching is based on the resin characteristics of plastic products. Whether the resin is polyethylene or polypropylene, their composition is different. When matching colors, you need to understand the color, gloss,?transparency, heat resistance, aging resistance, strength, etc. of the resin.
3. After completing the first two steps, we can match the color according to the color of the plastic product. In the process of color matching, we must consider the characteristics of the plastic and the requirements for pigments such as safety and environmental protection, and then select the appropriate pigment for color matching according to the requirements.
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In addition, the color matching of masterbatch must adhere to three principles, namely, “small amount”, “similar”?and “complementary color”?principles. “Small amount”?means the less colorant the better; “similar”?means the properties of the selected colorants should be similar, such as heat resistance; preventing the introduction of complementary colors is also called the “complementary color”?principle.
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pigment?is divided into organic pigments and inorganic pigments.
Commonly used organic pigments include: phthalocyanine red, phthalocyanine blue, phthalocyanine green, sun-fast red, macromolecule red, macromolecule yellow, permanent yellow, permanent purple, azo red, etc.
Commonly used inorganic pigments include: cadmium red, cadmium yellow, titanium dioxide, carbon black, red iron oxide, yellow iron oxide, etc.
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1) Brightener is an additive that can enhance gloss and is also a way to increase the brightness of masterbatch. During the production process, a certain amount of brightener can be added to make the surface of the masterbatch smooth and bright, thereby improving the quality of the product. 2) Transparent masterbatch is a colorless, transparent pigment additive that can also improve the transparency and brightness of the masterbatch, and can achieve good results. When using transparent masterbatch, it is necessary to control the addition ratio to avoid affecting the color and quality of the masterbatch.
3) Antioxidants can prevent pigments from oxidizing and deteriorating during processing
4) During the production process of masterbatch, the quality of the environment will also affect the brightness and quality of the masterbatch. Therefore, it is necessary to strengthen process control, ensure the cleanliness and good ventilation of the production environment, and reduce the pollution and impact of impurities.
5) If the masterbatch is used in injection molding products, 2% TiO2 or whitening agent can be added. Titanium dioxide can improve hiding power, weather resistance, anti-fading, etc. When the concentration of titanium dioxide is low, the whiteness of PP increases with the increase of its content. When the concentration exceeds 1.5%, the whiteness no longer increases. From 1%-8%, the whiteness increases by 2.8%. This shows that after exceeding a certain concentration range, increasing the amount of titanium dioxide does not improve the whiteness. In order to further improve the whiteness, fluorescent whitening agent can be used. Only a small amount of fluorescent whitening agent can significantly improve the coloring power of titanium dioxide. In general, the finer the titanium dioxide particles, the higher its coloring power and the stronger its hiding power.
6) Cadmium yellow has strong tinting power, excellent light and weather resistance, no migration and no color bleeding. This product can be used as a yellow colorant for plastics. It has bright colors, excellent light and heat resistance, solvent resistance, water resistance and alkali resistance, but it is not acid-resistant, and its coloring and hiding power are not very high.
7) Ultramarine has the effect of whitening and toning, and it can remove the yellow tint in white products.
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A. Choose four TiO2 formulas
Recipe 1
TiO 2 BA01-01 400G (40%)
Lithopone (zinc barium white) B302 300G (30%)
Brightener KSN 0.2G (0.02%)
Stearic acid YA-Ⅱ-200 type 30G (3%)
Calcium stearate 9.8g (0.98%)
LLDPE2433 Tianjin MI=33 100G (10%)
LDPEQ400(2F4B MI=4) 160G (16%)
*Ratio 3%
Recipe 2
(1) Titanium dioxide BA01-01 690G 69%
(2) Phthalocyanine Blue ICI.Ultranvawine NPB Blue RS-6
0.6G 0.06%
(3) Fluorescent brightener KSN 0.6G 0.06%
(4) Calcium stearoyl 10G 1%
(5) Stearic acid YA-Ⅱ-200 type 30G 3%
(6) 20PE Q400 268.8G/1000G 26.88%
* 4% for film blowing
Recipe 3
(1) Titanium dioxide 200G 70%
(2) Fluorescent brightener KSN 0.2G 0.02%
(3) Brightener EBS~oleic acid amide TAS-2A
25G 2.5%
(4) LLDPE 2433 150G 15%
(5) LDPE Q400 124.8G/1Kg 12.48%
* 4% Blown Film
Recipe 4
TiO 2 62.7%
LDPE(1F7B) 18.4%
LLDPE (7042) 4.6%
PE wax 12%
Oleic acid amide 2.3%
*Twin screw
145℃ 160℃ 170℃ 180℃ 190℃ 200℃ 195℃
Requirements: TiO2 content 63% MIR=7.5
Dispersibility, opening, heat sealing, printing
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B. Universal white masterbatch
PEwax 22%(Rushan)
TiO 2 64% (Pangang 101)
Zinc stearate 10%
CB cadmium red etc. 2%
A small amount of white oil, high stirring and then enter the three-roller single screw
Ratio 1:100
ABS is no problem, PP laundry tub (MI=35) has stripes (white)
Reason: Too much PEwax, which often causes it to melt first and produce streaks; after modification: PEwax is reduced to 15%, and there is no problem with PP. It is better to choose LLDPE, which has greater shear force and is easy to disperse.
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C. Black Masterbatch Formula
1) CB Cabot N234 45%
2) Pewax Beijing University of Chemical Technology 12%
3) LLDPE MI = 20 43%
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White coating film masterbatch
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White coating film masterbatch is mainly used for coating composite films such as instant noodles. Its main reference composition is:
Titanium dioxide (mainly R type) D50%-70%;
Low molecular weight polyethylene wax 2%-5%;
Polyethylene (1C7A) 20%-30%;
Appropriate amount of coupling agent;
CaCO 3 5%;
Other appropriate amounts.
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Polypropylene resin 45-60 parts Color powder 37-49 parts
Dispersant 2-7 parts
Antioxidant 0.5-1.5 parts
0.1-0.5 parts of UV protection agent;
The antioxidant is a mixture of antioxidant 1010 and antioxidant 168 in a weight ratio of 1:1-2; the anti-ultraviolet agent is a mixture of 4-benzoyloxy-2,2,6,6-tetramethylpiperidine and 2-hydroxy-4-n-octyloxybenzophenone in a weight ratio of 1:1.8-2.6
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1. Choose the right type of toner and the right particle size
2. Static Electricity
Many masterbatches do not contain antistatic additives. When customers use masterbatches, they often mix the masterbatches and raw materials together and stir them, which can easily generate static electricity. This causes uneven distribution of the masterbatches and raw materials when they are mixed, resulting in inconsistent colors before and after the product.
3. The melting point of the masterbatch is not suitable
4. In many cases, when selecting a carrier, masterbatch suppliers will choose a resin with a higher melt index as the carrier. However, the higher the melt index, the better. It is necessary to fully consider the physical properties of the final product, the surface requirements and the good processability of the masterbatch. A too low melt index can easily cause poor dispersion of the masterbatch in the product. The melt index of the masterbatch needs to be considered comprehensively with the conditions of the carrier and the powder. Designing a suitable melt index is of great help to the dispersion of the masterbatch.
5. The proportion of masterbatch added is too low
Considering the physical properties of the final product and the total cost of the coloring solution, some masterbatch suppliers will design a lower masterbatch addition amount, resulting in poor dispersion of the masterbatch in the finished product.
6. The dispersion system of the masterbatch is not suitable
7. In order to break up the agglomerated powder in the masterbatch, some dispersants and lubricants are added during the masterbatch processing to assist the dispersion of the powder in the masterbatch. If the dispersant is not selected properly, the masterbatch will inevitably have poor dispersibility.
8. The influence of masterbatch density
Color powders with high density are often added to masterbatches. For example, in order to achieve a strong hiding power of masterbatches, a large amount of titanium dioxide is added. The density of titanium dioxide is about 4.0g/cm3 (3.8g/cm3~4.4g/cm3), which is greater than the density of many resins. Therefore, the density of the masterbatch may be quite different from the density of the resin, and the masterbatch is more likely to settle at the bottom of the mixer during mixing, resulting in inconsistent colors before and after the product.
9. Improper selection of the carrier for the masterbatch
The carrier of the masterbatch is used to carry the color powder and other functional additives. The type, quantity, model, melting index and even form of the carrier will greatly affect the processability and dispersibility of the masterbatch. For example, for the masterbatch used in polyolefin products, whether the carrier is PP, PE or EVA, whether it is a single carrier or a mixture of several carriers, which brand, how much melting index is selected, whether it is powder or granular, etc., will all affect the final performance of the masterbatch.
10. Masterbatch Processing
The processing of masterbatch is a combination of multiple processes. What kind of mixing equipment should be selected? How to design the mixing process? What kind of granulation equipment should be selected? What kind of screw combination should be selected? What kind of granulation process should be selected? Even what kind of cooling process should be selected will affect the final performance of the masterbatch.
11.The impact of technology
The plastic molding process has a certain impact on the dispersion of masterbatch. As far as the injection molding process is concerned, temperature, pressure and holding time will affect the dispersion of masterbatch.
12.Impact of equipment
Plastic molding equipment will also have a certain impact on the dispersion of masterbatches. For example, if the screw is severely worn, the shear force will be greatly reduced, which will weaken the dispersion of the masterbatch.
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1. Formula design to determine the ratio of pigments, resins and additives.
2. Mixing choice: high speed mixer or gravimetric feeder?
Gravimetric feeder: suitable for that no?color changing system. Separate feeder for each kind of materials, it can help raw material more accurate feeding according to the formula. But it need to co-work with the high speed mixer.
High speed mixer: pre-mixing raw material before compounding
3. Pre-treatment: Grind and disperse the polymer into powder to improve dispersibility. Powder & powder mixing is better than granules & powder mixing.
4. High speed mixer mixing process: Add raw materials in batches and layers. For example: polymer 65Kg, pigment 30Kg, TiO2+additive 5Kg. First layer polymer 20kg, second layer pigment 15kg, third layer additive 3kg, fourth layer polymer 20kg, fifth layer pigment 15kg, sixth layer additive 2kg, seventh layer polymer 25kg. Low speed start the mixer and step by step increasing to the high speed with mixing 8-15 minutes until you find that material?can be held into a ball without being loose. You can record the mixing approx. Time and temperature and discharge with the similar time and temperature next batch mixing.
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Summary: recommend to use separate machines for Black/White/Colors masterbatch, because it’s hard to clean the machine when you change colors.
Black masterbatch:
Carbon black < 45%
1. High speed mixer + Twin screw?extruder with L/D 48:1 + Single?screw?extruder with L/D 7:1 or Gear pump + water ring(PE) or Underwater cutting system (PP&PE)
Design purpose: Double-stage?system, twin-screw high-pressure mixing and transmission, no head to avoid high shear and melt pressure overheating, single screw low speed and low shear to avoid overheating contradictions affecting material carbonization
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2. Kneader + single screw extruder with L/D 16:1 + water ring(PE) or Underwater cutting system (PP&PE)
Design purpose: kneader has a better mixing ability then mixer to get a higher performance.
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3. High speed mixer + Triple screw extruder with L/D 48:1 + Single?screw?extruder with L/D 7:1 or Gear pump + water ring(PE) or Underwater cutting system (PP&PE)
Design purpose: Triple screw extruder has a better dispersion ability than twin screw extruder, so it can work with maximum 55% carbon black adding.
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Carbon black > 50%
1. Kneader + Twin screw?extruder with L/D 48:1 + Single?screw?extruder with L/D 7:1 or Gear pump + water ring(PE) or Underwater cutting system (PP&PE)
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White masterbatch:
1. High Speed Mixer + Twin screw?extruder with L/D 48:1 + water ring(PE) or Die face hot cutting system (PP)
2. Kneader + single screw extruder with L/D 16:1 + water ring(PE) or Die face hot cutting system (PP)
3. Kneader + twin screw extruder with L/D 40:1 + water ring(PE) or Die face hot cutting system (PP)
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Color masterbatch:?
Due to the frequently color changing, normally recommend multi sets smaller capacity machine for easy changing different batch colors (normally 1-10 tons/batch). Like KTE-36, KTE-40, KTE-52 series machine.?Similar color?series can share one machine, like dark series color or light series color to reduce color?pollution.
High speed mixer + Twin screw extruder with L/D 40:1/44:1(KTE-36 series) or 44:1/48:1(KTE-52, KTE-65 series) + Water?cooling strand cutting?system.
Design purpose: mixer loaded upon the extruder directly to reduce the difficulty of cleaning. Equip with quick-open filter to easy open and clean the die head and screw.
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More advanced?design: The slide rail design allows easy separation of the barrel and gearbox, making it easier to clean or replace with?new screw to reduce cleaning time.
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1. Resin cleaning, using polyester resin or epoxy resin to clean the machine, is generally used for cleaning new equipment or when the extruder has been used for a period of time. Due to the gelation of some materials remaining on the screw or barrel, the material extrusion speed slows down, and the color difference of the color-changing varieties is large, this method can be used.
2. Disassemble and clean, manually add washing material from the feed port until the color of the extruded material strip is the same as that of the washing material pellets, stop feeding, empty the material, stop the screw of the twin-screw extruder; open the die head of the screw extruder and start cleaning; rotate the screw of the twin-screw extruder and remove the orifice plate, discharge the residual washing material in the barrel, and clean the orifice plate; stop and pull out the screw to observe whether it is cleaned, and manually remove the residual material on the screw. Reinstall the screw; add new material to flush the residual washing material in the barrel, stop the screw; install the orifice plate and die head of the twin-screw extruder, and complete the cleaning operation of the twin-screw extruder.
3. The fire baking method, which uses fire or fire baking to remove the plastic fixed on the screw, is the most common and effective method used by plastic processing units. Use a blowtorch to clean the screw immediately after use. Since the screw carries the heat from the processing experience, the heat distribution of the screw is still uniform.
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l Finished product particle inspection
Mainly inspection equipment: Lab Film blowing / Injection / Double roll tablet press machine
Masterbatch color detection: The same raw materials as the carrier are added in proportion (1% or 2%), and a 2.5mm thick sheet is obtained by injection molding at a temperature of 170°C-190°C (depending on the raw materials). The color is compared with the sample. When comparing, light colors can be tested with a colorimeter, and dark colors can be compared and adjusted under good light conditions based on experience.
Dispersibility:The films were pressed into the same proportions and temperature, and the number of pigment particles was observed.
Ash content and melt index test: Ash content is the proportion of ash after a certain amount of masterbatch is completely burned.
The melt index is the value obtained every 10 minutes at a temperature of 190°C and a temperature of 2-16 kg.
Tinting strength and shade test methods:Weigh 5g of masterbatch and 200g of natural resin and mix them evenly. Roll them into sheets on a two-roll plasticizer. Accurately weigh 10g of plasticized material and put it into a mold with a cavity height of 0.1mm. Use a pressure molding machine to press it into thin sheets and compare it with the original standard of known concentration. The color is similar to the standard, and the tinting strength is ±5% of the standard.
Fineness determination:Weigh 1g of masterbatch and 100g of natural resin and mix them evenly, then roll them into sheets on a two-roll plastic machine and observe the particle size under a microscope (count the number of pigment particles with a diameter of less than 0.5mm, 2nm, 10nm and above 30nm according to product requirements)
Contact Miss Cecelia: WhatsApp+86 13142836239 E-mail: [email protected]
Business specialist mgr. & ESG coordinator & Datamining
2 个月Nice article for color masterbatch field.