Which aspects of white masterbatch are worth considering?

1, whiteness

The whiteness of the white masterbatch is mainly manifested by the titanium dioxide in the color masterbatch, and there are many factors affecting the whiteness of the titanium dioxide, including the size, shape and particle size distribution of the titanium dioxide particles, the type and content of the impurities, and the lattice of the titanium dioxide particles. Defects. In general, since the chlorination method has a high purity of the raw material titanium dioxide and less impurities in the preparation process, the whiteness of the chlorinated titanium dioxide is better than that of the sulfuric acid method. In the real white mother market, many white masterbatch producers pretend to be titanium dioxide by adding equal ash content of calcium carbonate, barium sulfate and zinc sulfide. In fact, the whiteness of these inorganic powders is incomparable with titanium dioxide. .

2, hiding power

The hiding power is also a very important indicator of white masterbatch. The good hiding power means that the pigment has strong tinting strength, and the desired effect can be obtained with a small addition amount. The hiding power of the white masterbatch depends on the choice of titanium dioxide. Compared with the processing technology, rutile titanium dioxide has an smaller and tighter unit lattice and a larger refractive index than the anatase titanium dioxide, so the hiding power and ultraviolet light resistance are obviously superior to anatase. For the same type of rutile titanium dioxide white masterbatch, the titanium dioxide has a small particle size and a narrow particle size distribution. The opacity of the dispersion in the masterbatch is significantly wider than that of the titanium dioxide, and the dispersion is poor in the masterbatch. it is good. Similarly, the opacity of common calcium carbonate, barium sulfate, and zinc sulfide is also incomparable with titanium dioxide.

3. Dispersibility

Dispersibility has an important influence on the application of titanium dioxide in plastics. Generally, the finer the titanium dioxide particles, the better the dispersion, the higher the tinting strength, and the better the whiteness of the dispersion when the film needs fine printing. The grain pattern clarity, layering, and vividness are better because the microscopic smoothness of the base film is one of the determinants of the quality of the printed pattern.

4, moisture content

The moisture content in the white masterbatch also plays an important role in the performance of the masterbatch. Generally, the moisture content should be controlled below 1500 ppm, and the strict requirement should be below 600 ppm. In the injection molding process, the raw materials are generally dried before production. In the film production, the customer buys it directly after premixing with the carrier. If the moisture content of the masterbatch is high, it will directly lead to membrane rupture, and some small bubbles will form on the film, "crystal point". The reasons for the high water content of the white masterbatch are affected by the raw materials selected from the masterbatch to the process.

5, smell

Some film manufacturers will smell a strange smell after using the white masterbatch, which is absolutely not allowed in the milk film and the film in contact with food. This is mainly because the titanium dioxide in the masterbatch is organic. During the treatment, the selected coating aid is not appropriate or the amount of addition is too large, or the dispersant used in the production process of the masterbatch has problems, and the white master particle grade can be replaced.

6, hue selection

Rutile titanium dioxide has a low reflectance in the violet region, so the rutile titanium dioxide has a "yellowish" hue, and the "yellow" hue gives the colored product a "sand" feel and makes the fine printed image bright. Degree and layering are degraded, which is unpopular among many white masterbatch users. However, after adding a small amount of fluorescent whitening agent to titanium dioxide, it can absorb ultraviolet light with a wavelength of 300-400 nm and convert it into a wavelength of 400. -500nm blue fluorescence, so that the white masterbatch can be "blue phase", the white masterbatch users are considering according to their own needs.

7. Liquidity

The fluidity of the white masterbatch can be expressed as the melt index (MI), the value is low, the flow is good, the flow is good, the machineability is low, the power consumption is low, and the user chooses the white masterbatch. In addition to the requirement that the masterbatch has good fluidity, it should also be noted that the masterbatch of the masterbatch should be suitable for the carrier resin in the factory product. The general principle is that the MI of the masterbatch is higher than that of the carrier resin.

8, printing heat sealing performance

White film products require printing and heat sealing in most cases. If calcium carbonate is added to the white masterbatch to affect the sharpness and vividness of the printed pattern, the incorrect or excessive dispersing agent added to the masterbatch will also affect the heat sealing and Printing performance.

9, light and weather resistance

white masterbatch generally requires 7-8 grades of light fastness, 4-5 of weather resistance, and 280 degrees of temperature resistance. These requirements mainly depend on the quality of titanium dioxide. To achieve the above conditions, it must be rutile titanium dioxide. .

10. RoHS & FDA

Heavy metal testing and food contact permits are also an important indicator of white masterbatch, as many white films are used in food packaging and are subject to FDA food certification.

Jiangsu Hongmei Masterbatch Co., Ltd. is one of the largest polyolefin masterbatch manufacturers in East China, and its business scale ranks among the top in the domestic industry.

Hongmei products are mainly composed of plastic masterbatch, functional masterbatch and modified materials. The products are widely used in plastic processing enterprises such as injection molding, extrusion, coating, casting, drawing, blow molding and spinning. A good image with many varieties, complete chromatogram and stable quality has been well received by customers.