The application of laser marking machines is increasing year by year. The common ones are date laser marking, product information laser marking, two-dimensional code laser marking, bar code laser marking, etc. The anti-counterfeiting of packaging for all high-end daily consumer products is inseparable from laser marking machines. Due to the influence of material, appearance and other factors, customers will always encounter various problems in the marking application of laser marking machines. Today, MRJ-laser summarizes the common problems and related solutions of laser marking machines in the packaging industry as follows
Laser marking machine marking pattern is partially unclear
Causes: The thickness of the moulded plate is uneven, the moulding pressure is too small, the heating temperature is too low or the machine precision is not high.
Solution: Check whether the thickness of the moulded plate is uniform, whether the moulding pressure is too small, whether the temperature is too low, and whether the machine precision is reduced.
Key points of process control: the thickness error of the moulded plate should be controlled within 0.001mm, and the hardness should be kept at 230-280N/mm. Because the hologram is embossed with interference fringes by applying a certain pressure to the embossing roller, if the hardness of the embossed plate is not enough, the internal stress will deform or damage the embossed plate during the embossing process.
Laser marking machine marking pattern dull
Cause: Generally related to heating temperature and moulding pressure.
Solution: Check whether the heating temperature is too low. Whether the moulding pressure is decreasing.
Process control points: The setting of the moulding pressure should take into account the moulding temperature, the type of holographic material or the softening point of the coating layer, the condition of the moulding plate, etc. The pressure is too high and the moulded version is easily damaged or the holographic material is bad; the pressure is too low and the moulded image is not clear and incomplete for the initial pressure of the pressure rollers on both sides of the round pressing method is generally around 0.08MPa after the moulding starts. Slowly and evenly increase the pressure roller pressure to 0.30 ~ 0.50MPa. moulding speed can be adjusted according to the embossing quality machine performance.
Laser marking machine marking pattern white
Solution: Check if the moulding speed is too slow and the moulding temperature is too high.
Laser marking machine marking the film sticky plate
Cause: The hot pressing temperature is higher than the degradation temperature, and the viscosity of the coating increases, which will cause the sticky plate and make the film wind up on the holographic embossing roller.
Solution: Reduce the hot pressing temperature.
The marking pattern of the laser marking machine is clear and for someplace and blurred for someplace
Cause: Uneven temperature distribution of the hot pressing device or uneven moulding plate.
Solution: Check whether the temperature distribution of the hot pressing device is uniform and whether the moulded plate is deformed or worn.
Laser marking machine marking film with wrinkles in the horizontal (vertical) direction
Cause: Improper tension control of unwinding or winding.
Solution: Properly adjust the unwinding tension or rewinding tension until the wrinkles are eliminated.
Laser marking machine marking warped mark
Causes: The base of laser holographic marking is aluminium film, which has a certain degree of hardness; the viscosity of the adhesive is not enough. This phenomenon is easy to occur in the sealing and labelling of medicine boxes or wine boxes.
Solution: Properly reduce the thickness of the aluminium film, thicken the adhesive layer or improve the viscosity of the adhesive.
Process control points: the thickness of the adhesive should be mastered, especially in the summer when the temperature is relatively high, the adhesive will melt and overflow due to high temperature, resulting in printed matter rubbing dirty.
The above is about laser marking machine equipment in the packaging industry laser engraving common problems and solutions, the laser marking process of marking equipment selection not only affects the marking speed but also directly affects the marking quality.
