Frequently Asked Questions about COLD FOILS
The following substrates can be cold foiled:
- Clear Label, Wet Label
- Pressure Sensitive Paper/ Paper
- Coated Paper
- Paperboard
- Heat-Sensitive Material
- Plastic
- Shrink Film
- Pressure Sensitive Film/ Film
- IML
- Tube
Cold foil printing works best on non-porous materials.
Cold foils can be run up to maximum press speed, as long as the UV lamps have enough power to cure the cold foil adhesive.
The paper or board has a big impact. The shine and coating of the paper or board influences the degree of brilliance of the applied cold foil. A satin or glossy paper type will yield a shinier foil surface than a matte paper. Varnishes, which yield various surface finishes, are often applied after cold foils. A UV varnish or gloss laminate will provide a brilliant gloss finish, while a matte varnish will mute the shine. Spot applications of varnishes can produce dynamic surface differentiation.
The foil coverage can impact foil cost. Depending on foil layout, printers will sometimes order specially sized rolls of foil in order to minimize waste. A 10" foil roll doubles the foil cost of a 5" roll, so if a design only has a discreet area of foil, then cost can be impacted. Therefore foil layout planning can make a significant difference in big print runs.
While cold foil is not particularly sensitive to scratches, surface damage is more noticeable on foil because of the way light hits the metallic surface. If the finished product will be handled much or will be subject to wear, it is advisable to add a protective layer, such as a UV varnish or laminate.
No, it is not advisable. A good bond with the printed adhesive is critical to cold foil success. The porosity of uncoated paper absorbs adhesive, rendering it ineffective.
Yes. The standard color for cold foil is silver. It is popular because any metallic color, including golds and coppers, are possible through overprinting. Cold foil is also available in golds and various holographic patterns, including "rainbow" and custom options.
Yes, cold foil can be applied as halftones. The first printing tower prints the ‘adhesive ink’, which can be applied as a halftone. The foil only adheres to the printed adhesive, resulting in a halftone foil image. This is technically easier when not overprinting the foil, but with the right foil and a knowledgeable operator, it is certainly doable. See troubleshooting section.
Printing is typically followed by a coating to protect the printed foiled part. When using conventional adhesives, after a drying time of +/- 12hours, the printed sheets can be finished further. The adherence and drying of the print depend partly on the ink density on the foil surface. For example, you can have a maximum 250% CMYK ink density on foil, in addition to the 100% adhesive ink density (for a full-coverage foil).
Examples:
- Full cold foil coverage=100% density adhesive ink. On this silver-foil surface, you have the following print: 100C / 15M / 85Y / 25K for an ink total of 225% (ink density OK)
- Full cold foil coverage=100% density adhesive ink. On this silver-foil surface, you have the following print: 100C / 100M / 90Y / 30K for an ink total of 320% (ink density not OK)