彩涂板出现针孔的原因是什么

该小孔由基板于膜层表面，形成腐蚀通道。 彩涂板涂层表面周化后出现类似用针刺成的细孔，或像皮革毛孔那样，较大的称为麻点，是由于彩涂板涂层中能人T空气海和产生的其但气渔股裂，且在涂圆化前不能通过施平去推

产生原因:
(1) 彩涂板施工环境湿度过高，钢带表面上残留有水、油或其他不纯物，清除得不干净:(2)涂料的黏度过高，涂料本身紧密度不好和遮盖力较差;(3)涂料生产时本身夹带了空气和水分，或储存温度过低;
(4) 彩涂板涂料长时间被激烈搅拌，在涂料中混入空气，生成无数气泡;
(5)辊涂机涂敷辊速度过快，涂层过厚，溶剂被包裹在涂层中难以挥发;
(6) 彩涂板涂层在溶剂挥发初期的固化温度过高，由于溶剂挥发过快，使膜层本身来不及补足空当，形成一系列小穴，即针孔。
排除方法:
(1)涂料进仓后应在适当的温度下储存，防止低温引起析出、结皮、凝胶等弊病产生，在使用前需经过滤，除去杂质和碎屑;
(2)黏度要调配当，上机涂料搅拌时间避免过长;

(2)确保辊涂室的相对湿度不大于85%，确保钢带表面干净无油、水和被污染;(3)按工艺要求控制好辊涂速度，一次涂层不能太厚，湿膜厚度最好不超过 40pm;(4)固化炉的温度应从人口至出口方向由低温至高温设置，让溶剂能充分挥发。

The hole is formed by the substrate on the surface of the film to form a corrosion channel. The appearance of pinprick like pores on the surface of the coating, or larger pores like leather pores, is called pockmarks. It is due to the air and sea in the hu'ao coating, but the air and fish cracks, and can not be pushed by leveling before rounding
The causes are as follows
(1) The humidity of the construction environment is too high, and there are water, oil or other impure substances left on the surface of the steel strip, which are not cleaned up. (2) the viscosity of the coating is too high, and the tightness and covering power of the coating itself are poor（ 3) When the coating is produced, it carries air and moisture, or the storage temperature is too low;
(4) The coating is stirred intensely for a long time, and air is mixed into the coating to generate numerous bubbles;
(5) The coating speed of roller coating machine is too fast, the coating is too thick, and the solvent is wrapped in the coating and difficult to volatilize;

(6) The curing temperature of the coating at the initial stage of solvent volatilization is too high. Because the solvent volatilizes too fast, the film itself has no time to make up for the holes, forming a series of small holes, namely pinholes.

Exclusion method:

(1) the paint should be stored at suitable temperature after entering the warehouse, so as to prevent the occurrence of defects such as precipitation, crusts and gels caused by low temperature.

(2) The viscosity should be adjusted properly, and the mixing time should be avoided too long;

(2) Ensure that the relative humidity of the roller coating chamber is not more than 85%, and ensure that the surface of the steel strip is clean and free from oil, water and contamination（ 3) The roller coating speed should be controlled according to the process requirements, the first coating should not be too thick, and the wet film thickness should not exceed 40 pm（ 4) The temperature of curing furnace should be set from low temperature to high temperature in the direction of population to outlet, so that the solvent can be fully volatilized.