In some industries, in the printing process of uv printers, it is often encountered that the UV ink is not completely cured and the surface is sticky, which results in unsatisfactory printing results. How is this phenomenon caused? How to solve this phenomenon to ensure the quality of the print, here is a small compilation of the information for everyone to simply share.
Uv curing light source power is not enough
UV printer UV light curing has three elements:
1. The spectrum, that is, the light emitted by a light source such as a UV lamp is consistent with the absorption spectrum of the cured product.
2. The intensity, that is, whether the light emitted by the light source is sufficient, can cause photochemical reaction of the cured product, the performance of the internal sensitizer of different cured materials (UV coating ink, glue), the dose is different, the light transmittance of the main agent and the dosage agent The sensation is also different, so the curing strength requirements are different.
3, curing speed, curing speed is too fast to complete the curing, and too slow will have a bad effect on the cured product. If the pattern is cracked, the adhesion is not good. The curing speed varies depending on the cured product.
The fast printing speed of the Uv printer is also responsible for the incomplete curing of the UV ink and the sticky surface. At this time, the printing speed can be reduced or the light source power can be increased.
Uv curing light tube aging
The UV lamp is mainly a lamp that emits ultraviolet light. It is accompanied by high heat when it emits light, because it not only excites ultraviolet light, but also is accompanied by infrared emission. The wavelength of light is concentrated at about 365mm, and the ratio of infrared rays is different. The lamp content is different, the normal domestic UV lamp is about 30% longer, and the imported UV lamp has 40-50% content. At the same time, the calorific value is low, the service life is long, up to 2000 hours, and the domestic UV lamp is only 1000 hours. about.
As the electrode of the lamp is gradually decomposed, the inner wall of the lamp tube is deposited, and the transmittance of transparency and ultraviolet light is gradually weakened. Therefore, the lamp of the uv printer should be periodically detected, and the lamp tube should be replaced in time.
UV ink itself cures slowly
Photocurig refers to a certain photochemical reaction that occurs under the effective irradiation of ultraviolet light, such as UV ink or UV coating, so that the cured product becomes liquid and solidifies to form a pattern. This process can add a photocuring accelerator, reduce the printing speed or find ink. The supplier resolves.