UV light oil of common problems and solutions are introduced
A, luster, brightness is not enough
The main reason:
1. The UV light oil viscosity is too small, coating is too thin.
2. The reactive solvent such as ethanol diluted too much.
3. UV oil coating uneven.
4. The paper absorbency is too strong.
5. Anilox roll is too thin, oil shortage.
Solution: according to the different situation of paper increasing UV light oil viscosity and the amount of coating. The permeation absorbent strong paper, coated a layer of base oil can go ahead.
B , dry, light curing incomplete, surface sticky
The main reason:
1. The uv light intensity is not enough.
2. Uv lamp aging, strength weakened.
3. The UV light oil storage time is too long.
4. Don't participate in the reaction diluent to join too.
5. The machine too fast.
Solution: the curing speed requirements under the condition of less than 0.5 s, must guarantee the high pressure mercury lamp power is generally not less than 120 w/cm, to update the tubes, don't wait for the bad change again. When it is necessary to join a certain amount of UV light oil curing catalyst, accelerate drying.
C, printing surface UV light oil coating, hair flower
The main reason:
1. The UV light oil viscosity is small, the coating is too thin.
2. Printing ink contained too much ink oil or dry oil.
3. The surface of the ink has crystallization.
4. The printing ink adhesion on the surface of materials (such as silicone oil, powder).
5. Plastic net roller is too thin.
Solution: require UV glazing products printing must take corresponding measures to create conditions and thicker about 1/8-inch-thick appropriately when the UV light oil, when necessary, through the bottom oil or replace special light oil to solve the problem.
D, UV glazing coating with white spots and pinhole
The main reason:
1. The coating is too thin.
2. The anilox roll is too thin.
3. The reactive diluent (such as ethanol) join the amount too much.
4. Print surface dust, etc.
Solution: and print surface shall be kept clean production environment, increase the coating thickness. Also can add a small amount of smoothing agent. Had better use the to participate in the reaction of reactive diluent dilution.
E, the surface coating unevenness, stripes and orange peel phenomenon
The main reason:
1. The UV light oil viscosity is too high.
2. The applicator roll is too thick not smooth.
3. The pressure is not uniform.
4. Large amount of coating.
5. Poor flowing property of UV light oil. Solution: reduce the UV light oil viscosity, reduce the amount of coating. Uniform pressure adjustment. Applicator roll should be fine grinding and polishing. Light energy flow ping agent can be added.
F, UN light oil, adhesion is not good
The main reason:
1. Print ink surface crystallization.
2. The auxiliary material in the printing ink is not appropriate.
3. The UV light oil itself insufficient adhesion force.
4. Light curing conditions are not appropriate.
Solution: printing process to consider polishing conditions in advance. Have printed products need coated with enhanced adhesion at the bottom of the oil.
G, UV light oil thickens, gel phenomenon
The main reason:
1. The UV light oil storage time is too long.
2. Light failed to completely avoid light oil storage.
3. The storage temperature on the high side.
Solution: pay attention to the UV light oil could effectively and strictly avoid light storage. Storage temperature for 5 ℃ ~ 25 ℃ advisable.
H, residual smells great
The main reason:
1. Dry curing not thorough.
2. The uv light source is insufficient or lamp aging.
3. The UV light oil antioxidant interference ability is poor.
4. UV light oil china-africa reactive diluents add too much.