To solve the UV light oil in the paper surface smoothness is unwell
In daily production process, a variety of reasons require us to dilute the UV light oil, usually the most economical, the most convenient way is directly in the UV light oil A.T industry with a reactive solvent such as ethanol, without changing the UV light oil under the condition of natural ingredients, only change the UV light oil viscosity instantly, improve the liquidity of light oil and the transfer eligibility, make the light oil curing after print to achieve smooth surface. After joining too much but when ethanol, ethanol contains moisture volatilizes not completely, will be produced in the process of curing light heating water mist, and residue in light oil film, the influence of light oil curing film after the transparency, and even lead to curing incomplete, print surface sticky.
Solution: in the process of production should be as much as possible to control the addition amount of non reactive solvent such as ethanol, also should choose the purity higher ethanol. UV light oil coating evenly
UV light oil coating unevenness is also affect the printing surface gloss and brightness is one of the main reasons, and UV light oil coating effect with polish version, printing pressure, anilox roller and ink has a direct relationship.
(1) plate embossed surface height difference will affect the consistency condition of light oil transfer, thus affect the quality of the light oil coating.
(2) the printing pressure unevenness can also affect the light oil to the transfer of the substrates, leading to transfer to the different thickness of the UV light oil on the substrates.
(3) the anilox roll net hole clogging, the anilox roll surface uneven ink storage quantity, which can lead to UV light oil to the surface of the substrates congenitally deficient.
(4) printing ink and UV light oil rejected or interference, and too much ink surface containing viscous materials, can make UV light oil to the surface of substrates to transfer partial obstruction.
Solution: choose version base excellent flexible plate; Pay attention to the effectiveness of the developer and; In the washing quality, to ensure a uniform plate embossed surface height; Printing pressure adjustment, to ensure its moderate stability; Thoroughly clean the anilox roll, ensure no foreign bodies in the mesh point remaining: choose the same manufacturer production of printing ink and UV light oil, avoid to add viscosity in ink additives.
Paper surface smoothness is not appropriate
Paper surface rough, directly affect the UV light oil on the surface of the paper, flow flat performance. When the paper surface too rough, UV light oil on the surface of the paper, the flow speed is slow, transferred to the UV light oil for almost all of the paper surface is rough paper absorption, makes the UV light oil of film-forming substances - infiltration between fiber photosensitive resin, after UV curing printing surface gloss and brightness are not good. In addition, the paper surface rough, can also affect the UV light reflection, diffraction and interference, lead to UV light failure, affect the curing effect.
But the paper surface smoothness is not the higher the better. Because the paper table is too smooth, the absorbent poor, printing ink cannot be effective penetration on the surface, the ink on the surface crystallization, forming the absorbent surface. On the surface of UV glazing, penetration of light oil composition is stranded in the paper surface with photosensitive resin, will make the light oil curing not thorough.
Solution: choose good paper printing eligibility, and can also be printed in the paper surface dilution: in the light of the white ink, to change the surface roughness, delay the absorption rate. In addition, you can use water-based light oil to improve the paper surface printing eligibility render, it also can improve the bending of printed matter.