Method of spun-bonded non-woven fabric is of the fastest growing varieties in non-woven industry, about 40% of the total non-woven fabric production. With polypropylene as raw materials of spun-bonded non-woven products are widely used in medical, health materials, furniture, cloth, carpet base fabric, decorative materials, shielding materials, automobile industry, etc.
 
Polypropylene is a kind of pure linear saturated hydrocarbon polymer, large molecules containing no polar group and reactive group, high chemical stability. Higher crystallinity of polypropylene fiber, dense structure, strong hydrophobicity, these characteristics make polypropylene provides dyeing, dye molecules are unable or difficult to spread to the interior. Therefore, in order to improve the practicality and aesthetics of polypropylene non-woven fabric, in the production of the color masterbatch spun-dyed method is adopted.
 
The composition of masterbatch choose masterbatch is refers to the pigment according to the proportion of 20% ~ 80% by grinding or twin screw extruder evenly dispersed in the resin color is made by particles, with shading effect is good, convenient automatic metering and transport, energy saving, no dust, no pollution, etc. International concentrated masterbatch market in the United States, Western Europe, Japan and so on, our country masterbatch manufacturer main distribution in guangdong, zhejiang, jiangsu, shandong, Beijing, Shanghai and other provinces and cities. In the method of spun-bonded polypropylene production, the composition of masterbatch is mainly from the following several aspects to consider.
 
Pigment:
Pigment is the main component of masterbatch, there are mainly two categories: inorganic pigments and organic pigments.
 
 
Inorganic pigments for metal oxide and sulfide or metal salt, commonly has better light fastness and weather resistance, this for poor light resistance of polypropylene resin is of great significance. The downside is particle size is bigger.
 
Organic pigments have strong tinting strength, good dispersibility, colour and lustre bright-coloured, but its light tends to cause desaturation, easy create shading products fade, suggest to choose suitable inorganic pigment particle size. Paint the heat resistance of mean temperature in the production or use the color of the paint or performance change of temperature, its heat resistance at 250 ℃, the non-ferrous products color small; At the same time, the selected pigment resistance transference to > 5, light fastness level 6 ~ 8, with polypropylene resin has good compatibility, good synergistic effect with other additives, firmly in the process of spinning processing staining. For medical and penetration, cannot contain in pigment with a health hazard of heavy metal elements, such as cadmium, lead, mercury, etc. Pigment particle size directly influence on the performance of the pigment dispersion degree and finished product, if the pigment particle size is too small, specific surface area, surface free energy is bigger, is easy to gather together and cause its poor dispersion in polypropylene resin; If the pigment particle size is big, will be in production blocking filter plate and the nozzle, makes the fiber increase, the broken ends when stretched wool yarn and make even resin or additives due to stay a long time and cause thermal decomposition, affect the physical and mechanical properties of the fiber. General pigment particle average size control between 0.1 m - 0.5/1.
 
The carrier
Carrier is the matrix masterbatch, can make the masterbatch is granular, accounts for 30% ~ 50% of masterbatch, carrier and pigments have good affinity and compatibility, choosing a carrier to consider the compatibility with the resin being shaded and its effect on the performance of shading system other.
 
Because the spinning speed of spun-bonded method is larger, the molecular weight and its distribution of the carrier to the more stringent requirements, recommend choose melt index about 2010 min of metallocene catalyst for synthesis of polypropylene. Using metallocene catalyst for synthesis of polypropylene, the molecular weight distribution coefficient of < 4, can effectively improve the Concorde and dispersion of pigments in masterbatch, finished coloring and firm, enhanced sense of beauty, physical and mechanical properties, can be prepared into pigment content is 80% of the concentrated masterbatch, reduce the production cost.
 
dispersant
Dispersant can package on the pigment particle surface, reduce the surface free energy of pigments, pigment dispersion into fine particles, stable and evenly distributed in the melt, and does not occur in the process together. Usually require dispersant and pigment has a good affinity, and the carrier has better compatibility. Tell from the economical and practical, it is suggested that using polypropylene wax as dispersant, its high softening point, narrow molecular weight distribution, no smell, can significantly improve masterbatch coloring ability, reduce the color difference, reduce the interruption of spinning silk, silk phenomenon. The most commonly used dispersants such as powder, flake. Is bigger than the ordinary wax particles of pigment particles, parcel uneven of pigment particles, powder wax is a suggested alternative. Powder pigment particle size and size close to wax, wax powder particles filled between the pigment particles can make the pigment particle distance and provide wetting effect, can significantly improve the dispersion of pigment.
 
Masterbatch of quantity
The amount of the masterbatch directly affects the dyeing effect of spinning technology and products. Add quantity is little, dyeing depth or uneven dyeing, join the amount is too much, will form the human impurities, increased the difficulty of spinning. At the same time due to the melting point of masterbatch was lower than those of conventional slice, the gray level is high, which makes the melt viscosity changes, spinnability, the tensile properties of strips. Practice shows that when the addition amount was 1.2% ~ 1.2%, dyeing, finished product has good spinnability. 
 
 
Mix one location of masterbatch
Masterbatch, after all, with conventional slice quality index of the differences in order to reduce the thermal decomposition masterbatch, conditional manufacturers, heating molten masterbatch should be separately USES a dedicated small screw, and through the metering device with large screw in the melt direct blend into the melt filter.
 
Other aspects
In order to reduce the color difference of products, in production and pay attention to the following link:
 
(1) to establish each masterbatch under a certain proportion of the standard sample, according to the proportion of mixed into the factory in the sample of masterbatch in sampling inspection, and comparing with standard sample;
 
(2) into the factory with varieties, masterbatch were mixed with batch number, the same variety, different batches of masterbatch to be mixed;
 
(3) in front of the masterbatch to screw, try to remove particles is too big or too small in the masterbatch, to ensure that the molten evenly and completely in the screw;
 
(4) in the production of a color number to try not to change the color masterbatch batch number. 
 
Off color is color spinning viscosity method is a common phenomenon in the polypropylene non-woven fabric production, the reasonable choice and correct the composition of masterbatch process control can be the greatest degree of general color difference control in a reasonable scope, improve the quality of the products.
 
Yancheng ze masterbatch co., LTD mainly non-woven masterbatch, black masterbatch, non-woven masterbatch masterbatch products such as function. If necessary, welcome to contact us!