(1). Laminating temperature
Temperature is the primary factor for laminating. According to practical experience, coating temperature should be controlled at between 95~130 Celsius degree.
(2). Laminating pressure
The paper surface is not smooth, and only under the appropriate pressure, molten state of hot melt adhesive will completely cover the printing surface. In actual production, adjust the pressure according to the different paper. For example, loose paper, the pressure should be stronger, instead of lighter for tight paper. According to experience, laminating pressure is generally set to appropriate 6 ~ 20MPa.
(3). Laminating speed
The speed of laminating determines the time of pre-coated adhesive on the heating roller and melting time on the film and paper contact time. Domestic facilities speeding rate is generally controlled between 15 ~ 80m/min.
(4). Special printing lamination controlling data
Special print refers to the large area printing, thick ink, deep color, large water content of paper, large size paper printing. To laminate on such printing sheet, the general laminating data is as follows for reference:
Lamination temperature: 95-115 degree Celsius
Lamination pressure: 16-25Mpa
Lamination speed: 5-10m/min
(5) Other factors which affect laminating quality
It is better to use light quick-drying ink for printing on the product if it need to be laminated, but it is not good to put too much catalyst, otherwise the ink will crystallize on the surface. In addition, the ink viscosity, oil content etc. will affect laminating quality as well.
(2). The state of the Adhesive coating
BOPP film’s adhesive layer requires to be uniformity and thin, under the premise of the ensuring strong bond, should try to select the appropriate laminating thermal film with good adhesive; otherwise it will affect the quality after laminating.