Analysis of two kinds of cold stamping technology
The first type of wet test cold stamping
The wet cold stamping method is to apply an image of the UV adhesive to the substrate, and then apply the cold foil to the substrate with a pressure roller, and dry the UV glue on the substrate with a UV lamp to make the image sticky. Remove excess foil. The main process steps are as follows:
1. Printing free radical UV adhesive on the roll substrate.
2. Fit the cold stamping foil on the substrate.
3. Curing the free radical UV adhesive. Since the adhesive is sandwiched between the cold stamping foil and the printing village, the UV light must pass through the hot stamping
foil to reach the adhesive layer.
4. Strip the hot stamping
foil from the substrate and form a hot stamp on the substrate. Since the wet cold stamping process replaces the traditional cationic UV adhesive with a free radical UV adhesive; the UV adhesive has a strong initial tack and can be tacky after curing; and the metallization of the hot stamping
foil The layer should have a certain light transmission to ensure that UV light can pass through and initiate the curing reaction of the UV adhesive. Wet cold stamping technology can be used on the press.
The second type of dry cold stamping
The early cold stamping technology adopts the dry cold stamping method. The dry cold stamping technology processes the image on the substrate, and uses UV lamps to dry and cure the UV glue on the coated substrate to make the image sticky. Use a pressure roller to turn the foil onto the attached image and remove the excess foil. The main process steps are as follows:
1. Printing cationic UV adhesive on the roll substrate
2. Curing the UV adhesive.
3. The cold stamping foil is combined with the printing material by means of a pressure roller.
4. Strip the excess hot stamping foil from the substrate and leave only the desired hot stamping on the adhesive.
When dry cold stamping is used, the curing of the UV adhesive is carried out quickly, but it cannot be completely cured. It is guaranteed to have a certain viscosity after curing, so that it can be well bonded with the hot stamping foil.