Factors Affecting Powder Coating Gloss and Its Measurement
In the current market, powder coating is a widely used material. In addition to energy saving and environmental protection, the price of powder coatings is also relatively low with good use effect. But we believe that you will often encounter issues such as gloss, ingredients and how to classify these products. The following focuses on answering everyone.
Let's talk about the distinction of gloss first. If it is classified according to the different powder coatings gloss, there are high-gloss, flat-gloss, matt gloss. The gloss of high-gloss powder coatings is generally greater than 75GU, while the flat-gloss type is between 45GU and 75GU. The gloss between 10GU and 45GU is matte. The gloss of matte powder coating is below 10GU. In addition, the powder pigments used in different environments are also different. For example, high-gloss powder pigments are mainly used outdoors and are relatively temperature-resistant. Most of them are used in air conditioners or street lamps.
1. Factors affecting powder coatings gloss
(1) Effect of acid value and polyester dosage on gloss of coating film
As far as powder coatings are concerned, the choice of raw materials also directly affects various properties of the coating film, including the coating film gloss. Therefore, before producing powder coatings, we must be specific about what kind of polyester is used to produce coatings.
(2) Effect of filler on powder coating film gloss
The filler has a matting effect on the coating. The principle is that the filler covers the coating film entire surface, destroying the flatness of the coating film and causing a rough surface. However, it is not possible to rely solely on fillers to dull the coating. Only when the amount of filler reaches a critical volume concentration will the best matting effect be achieved.
(3) Effect of mixed powder method on coating film gloss
The so-called mixed powder method refers to the use similar materials which have different reactivity. At least two kinds of powders are first prepared and then mixed together to achieve the purpose of extinction by this means.
(4)The effect of the matting curing agent on coating film gloss
The purpose of using the matting curing agent is mainly to adjust the coating film gloss, so it is easy to produce a misunderstanding: as long as the amount of the matting curing agent is adjusted, different gloss coating films can be obtained.
In addition, there are other factors that also affect the powder coatings gloss, as follows:
① Mixed curing agent, that is, several curing agents with different activities are added during the manufacturing process of powder coatings. The difference in chemical reaction activity and the curing speed are different, resulting in uneven shrinkage and matting effect;
② matting wax; ③ baking temperature; ④ curing time; ⑤ resin structure.
The coating film surface gloss is selected according to the requirements of the user. In general, noble, beautiful, luxurious decoration requires high gloss; Quiet, comfortable and elegant environments require lower gloss. Generally, high-gloss is required for machinery, car shells, highway guardrails, etc. used outdoors; Low-gloss is required for the cabs, instrument rooms and office equipment of cars and boats used indoors.
2. How to measure the powder coatings gloss?
The specific powder coatings gloss cannot be measured and evaluated by the naked eye. If you want to measure the powder coatings gloss, you need to use the Linshang LS192 gloss meter. Linshang LS192 gloss meter can be used to test the surface gloss of coatings, paints, plastics, paper, tiles, stone, metal and electroplated products. The measurement range can reach 1000GU. The test data can be comparable to the German BYK gloss meter.
In addition, the LS192 gloss meter measures in real time, that is, the measurement is performed immediately without pressing the button. The measurement data is displayed in real time. At the same time, the gloss meter has intelligent statistics function and the number of measurements, maximum value, minimum value, average value and standard deviation are directly displayed on the display interface. What's more important is that the LS192 gloss meter has the function of ambient temperature compensation and the value is stable, allowing long-term calibration. The LS192 gloss meter also supports USB transmission and comes with operating software, which can be operated online with the computer and complete the test report. It can easily help us accurately detect the specific powder coatings gloss.