1. Hanging
A. Causes of sagging: The viscosity of the coating is too thick.
The reason for spraying too thick: the distance between the Spray Gun and the workpiece is too close for multiple sprays, and the spraying is too thick once, such as the Spray Gun moves too slowly then stops.
B. Solution:
In wet-to-wet construction, there should be sufficient flash-off time for secondary spraying. For thin coating, the flash-off time is 3-5min. With the increase of spraying times, the flash-off time increases to 5-8min.
C. Ensure that the vertical distance between the Spray Gun and the workpiece is constant.
D. The moving speed of the Spray Gun should be uniform to avoid direct shooting and turning back on the workpiece.
E. If the viscosity of the paint is too low, it should be diluted strictly according to the ratio of diluent.
F. The solvent volatilizes too slowly. Use a special thinner to increase the temperature of the construction environment and strengthen ventilation.
G. Poor wettability on smooth old coatings. Sand it beforehand.
2. Orange pattern
A. If the solvent evaporates too fast, the viscosity will increase sharply and the leveling will be difficult. According to the seasonal ambient temperature, select a suitable thinner to reduce the temperature to below 40 degrees.
B. The amount of paint sprayed is too small, the distance is too far, and the paint film on the surface is too thin. Difficult to level.
C. The poor atomization particles of the Spray Gun are too large and difficult to level. Reduce paint output and increase compressed air output.
D. The fluctuation caused by the Spray Gun being too close to the air causes orange streaks on it. Keep the Spray Gun away from the workpiece.
E: The substrate is uneven or the thinner evaporates too quickly. The substrate is uneven or the thinner evaporates too quickly.
3. Out of the bottom
reason:
The hiding power of the paint is reduced due to the addition of too much thinner
Some pigments in the paint are precipitated and the precipitated pigments are not fully stirred during use.
The thickness of the coating film is too thin or there are some missing coatings
Insufficient surface treatment of the substrate will result in inconsistent wetting of the paint to the surface during painting, resulting in uneven coating film and partial exposure of the bottom.
Solution
Control the amount of diluent used within a reasonable range
Stir well before use
When painting wood substrates, pay attention to surface treatment and perform proper sealing coating
Careful coating to prevent less coating and missed coating and strive for uniformity
For the exposed Mike, according to the situation, make spot repairs on individual parts or sand the whole with sandpaper and then repaint .
4. Pinhole
Cause of symptoms:
1. Add too much dilution water.
2. Too much paint is too thick each time, and the respraying time is not appropriate.
3. The surface of the object is uneven, unclean, complex in shape and contains oil and water.
4. The nozzle is too large The distance between the nozzle and the object surface is too close.
5. The spraying speed is uneven and the interval between layers is not enough.
Solutions to symptoms
1. Add diluent in proportion.
2. It should be sprayed twice, with an interval of ten minutes each time, and each coat should not be too thick.
3. Handle the sprayed surface without water and oil.
4. Correct selection of Spray Gun caliber. It is advisable to keep a distance of 20cm-25cm between the Spray Gun and the object. 5. Adjust the viscosity of spraying and brushing to master the speed of coating and spraying.
5. Bleeding
After the topcoat is applied to the topcoat, the color of the bottomcoat penetrates into the surface due to the action of the topcoat solvent. This condition is called "bleeding". Most topcoat colors are light and the primer color is deep.
1. The primer contains oil-soluble pigments or dyes
For example, when a painter sprays A04-9 red amino paint, in order to save money, he often pours the red thinner for washing the spray into F06-1 red
In gray phenolic primers or other red primers that are considered red anyway this often ends up showing up when spraying light colored topcoats
flushing phenomenon.
2. Spray paint containing strong solvents such as nitro paint on the wet primer.
Common faults and treatment methods of paint coatings - biting the bottom
It means that the solvent in the topcoat can easily soften the paint film of the primer and even affect the adhesion between the primer and the surface.
The phenomenon of biting the primer after painting is called "biting". Slight biting is very similar to wrinkling of the paint film.
1. Paint the top coat before the primer is dry
For example, H06-2 Iron Red Epoxy Ester Primer F53-31 Hongdan Antirust Paint has excellent performance at high temperature in summer, but as the temperature drops, especially in winter, it will wrinkle and bite the bottom of the topcoat on them. There are more and more complaints, mainly because the drying speed of these two paints has a great relationship with the temperature. Take iron red epoxy as an example. When the temperature is high in summer, it usually takes a day dry and spray the top coat containing strong solvents. It will bite the bottom and wrinkle, and its self-drying time winter Dry for 1 hour at Celsius. If there is no drying equipment, it is recommended to extend the drying time or choose other quick-drying primers.
2. The primer and topcoat are not matched
If the primer itself is a paint that is not resistant to strong solvents, such as red phenolic antirust paint or iron red phenolic antirust paint, and the topcoat contains strong polar solvents such as nitraldehyde paint, polyurethane paint, even after the primer is dry, it will still produce bite. Bottom phenomenon.
3、双组份漆固化剂漏气造成一定程度的树脂胶化或油漆配制进间过长后进行涂刷使油漆的最终成膜质量下降抗面漆溶剂的渗透溶胀能力下降从而引起咬底。
4、底层使用了抗强溶剂性能差的挥发性腻子或油漆而高层使用聚酯与聚氨酯类热固化性树脂漆这种咬底往往在上第一层面漆时不会产生咬底而即使第一层面漆充分干透后再上第二层面漆时即出现咬底现象主要原因是由于第二层面漆强溶剂渗透过第一层面漆引起挥发性腻子发胀从而产生咬底。
6.脱落
原因：
施工时加入过量水稀释造成漆膜太薄;
墙面基底碱性(PH值大于710)过高漆膜被破坏。通常发生于未干透的新墙;
墙面基底及环境湿度过高重涂时间短通风差;
施工时墙面基底温度过低
墙面基底(如打底的腻子)太疏松;
涂刷时未完全成膜一般施工后7天才能完全成膜;
将内墙漆用于户外。
解决方法：
铲除粉化层;
重新选用良好的油漆如多乐士墙面漆系列;
遵循施工规范切勿用水过度稀释;
必要时需选用合适的底漆对墙面基底进行封固处理提高面漆附着力。建议使用多乐士底漆系列;
保证施工环境符合施工要求。
7.遮盖力不良
现象：虽然施涂数道涂料但却未能达到希望的色泽仍然露出底材的颜色。
成因对策
涂料底、面涂色泽配合不当底色用浅色或接近面涂颜色涂料调合、混合稀释不当充分搅拌、不可过度稀释涂膜厚度不足施涂适当厚度的涂膜被涂物边角形状影响针对各种形状给予适当的涂装未干底层漆上做上层涂装待底层漆干透再做上层涂装基层太湿不易涂刷基层干燥后涂刷局部地方漏涂顺次涂刷避免漏涂
8.开裂
1)油漆本身耐候性差不易在户外使用。
2) Thick coating and pouring floor paint use thick coating and pouring during use to greatly increase the possibility of cracking of the paint . Generally speaking, when the total amount of paint used per square meter does not exceed 0.8 kg. big.
3) The ratio of the curing agent is too high or the hardness of the paint itself is too high and the toughness is insufficient.
4) The bottom layer itself is loose and cracked, causing the upper paint film to fall off and crack.
9. Bite the bottom
It means that the solvent in the topcoat can easily soften the primer film and even affect the adhesion between the primer and the surface. This phenomenon of biting the primer after the topcoat is applied is called "biting". Paint film wrinkling is very similar.
1) Paint the top coat before the primer is dry
For example, H06-2 iron red epoxy ester primer and red lead antirust paint have excellent performance at high temperature in summer, but as the temperature drops, especially in winter, the complaints about wrinkling and biting of the top coat on them become more and more serious. More and more mainly because the drying speed of these two paints has a great relationship with the temperature. Take iron red epoxy as an example. In summer, when the temperature is high, it usually takes a day to dry. In winter, when the temperature is low, its self-drying time will take 5 days or longer. The next day's application of the topcoat will easily cause the problem of bottoming. We suggest that iron red epoxy primer should be dried at 120 degrees Celsius for 1 hour in winter. If there is no For drying equipment, it is recommended to extend the drying time or choose other quick-drying primers.
2) The primer and topcoat are not matched
If the primer itself is a paint that is not resistant to strong solvents, such as red phenolic antirust paint or iron red phenolic antirust paint, and the topcoat contains strong polar solvents such as nitraldehyde paint, polyurethane paint, even after the primer is dry, it will still produce bite. Bottom phenomenon.
3) Leakage of the two-component paint curing agent causes a certain degree of resin gelation or the paint is prepared for too long before painting, so that the final film-forming quality of the paint is lower
