Laminating problems and solutions MACtac（层压MACtac问题和解决方案）.pdfVIP

TECHNICAL BULLETIN 7.8 - V2-September 2012 Laminating problems and solutions 1.Bubbling issues: Few laminator problems look worse than bubbles under the film. Bubbles are caused by a lot of problems: insufficient tension on the supply roll; feeding the leading edge of the print too quickly into the laminator; too much heat on a wet print, causing outgassing of the ink; the adhesive not bonding properly to the media, and others. Insufficient tension causes bubbles when air gets trapped between the film and image because the film wasnt taut as it entered the nib (caused by lack of supply roll tension). Insufficient tension is obviously fixed by adjusting the tension of the feed spool to the proper specifications for the type of film youre using. Thinner film needs less tension, for instance. Too little supply roll tension will cause bubbles before it will cause wrinkles in the film Feeding too quickly causes bubbles if the item is pushed into the nip faster than the speed of the laminator. The solution to this problem is too obvious to mention. The heat issue like “hot spots is a key problem when laminating inkjet prints. Inkjet printers dump a lot of ink onto the print, and a rushed operator may try to laminate the image before the ink is completely dry. The problem can be exacerbated by the fact that if a laminator is allowed to sit for extended periods of time without the rolls turning, there can be varying degrees of temperature on different parts of the rolls. This creates areas called hot spots. If youre running a laminator at 85°c, the point where the rolls sit together can easily become a hot spot of ±95°c. When a moist inkjet print encounters one of this hot spot, the ink can easily boil, creating bubbles. Among the solutions to heat-related bubbling is not to let your rolls sit idle for extended periods of time, to speed up your laminator so less