It’s important to understand that when planning a commercial foil stamping and or embossing project that, in most cases, it is not a “same-day” process. It can take a number of days for a Brass embossing die to be made. Magnesium dies can be manufactured on the same day by your die maker or die department but that is depending on what time the die is ordered. However this is not always possible and or could be very costly. In most cases Magnesium dies are a one or two day service. Special grades of polymer plates are available for hot foil printing and if an in-plant photopolymer platemaker is available, then you would be able to make suitable plates within 30 minutes of your artwork being created. Hot foil printing grades of photopolymer plates are only suitable for low speed low volume print runs.
For projects that require sophisticated dies and processes it is always recommended that the designers discuss the project with the die makers and the printers. Sometimes a little thought and discussion could result in a slight alteration in project design, which could greatly simplify, and drastically reduce make-ready times on foil stamping and embossing projects. Where possible involve your print finisher early in the project planning process to see if alterations can be made to reduce cost and or turnaround times for your project.
Selecting the right stock for your project can be the difference between a high quality print and or embossing finish or an average quality or even a poor quality finish. Weight, finish and coatings all play an important role in the visual appeal and overall quality of the finished project.
As a rule of thumb, medium-weight uncoated stocks are the ideal choice for most embossing applications; however this does depend on the depth of the image on the die and the thickness of the substrate. If the embossing die or the embossing element of the die (multi-level die) is not designed to be used with the substrate of your choice, the embossing may not reveal all of the intricate detail present on the die. In addition, if using textured stock, the embossing may “iron out” as the substrate is stretched during the embossing process. The resulting effect may or may not be what you are looking for.
When foil stamping, substrates that are very porous may cause the foil to push too deeply into the substrate. The result may be colour that appears washed out, or metallic foils with an uneven surface finish. Deep embossing into a foiled substrate may cause the substrate to split, however this is very dependent on the size and depth of the image. An important consideration if planning to use heavily-coated substrates is that they have a tendency to crack on deep, multi-level embossing or debossing applications. Before a project is printed and or embossed, let your print finisher help you select a suitable substrate that will yield the best stamping and embossing results.
Another point to consider when selecting paper and inks is the temperature of the stamping and or embossing die. During the embossing process, metal dies are heated to temperatures in access of 120°C /250°F. These temperatures can cause heavily-coated stocks and or thick ink impressions to stick or even burn when the die makes contact with the substrate. If the project is already printed (offset, letterpress, flexo etc.), a polyester sheet may be placed between the substrate and the die. If your project calls for heavy ink coverage or coatings check with your print finisher for advice.
For embossing or hot foil stamping, plan your project layouts very carefully, as consideration must be given to a number of factors. For example, when hot foil printing, metal dies will expand when heated. Although the exact amount of expansion depends on the surface area of the die and the amount of heat applied, large dies can expand by as much as 1.5mm (1/16”). Images that are to be placed in close registration should be planned to account for this amount of expansion. Whenever possible, position areas of tight registration as close as possible toward the gripper and side guide of your foil printing machines. This will help maintain consistency throughout the production process, especially on intricate multiple-up projects.
Paper shrinks when hot foil printed or embossed. The exact amount of shrinkage is dependent on the shape and depth of the die and the characteristics of the paper or card. The shrinkage can noticeably alter the dimensions of the sheet and prevent sheets from lining up properly. An experienced print finisher can advise you on the changes of the paper dimension on both registered and blind embossing projects.
Good communication between the printer and the print finisher is crucial in most successful project. Involving the print finisher during the project’s planning stage is perhaps more important for stamping and embossing applications than any other finishing process. The complexity and detail involved in die creation makes it a necessity to gather as much information as possible from the customer.
Hot Foil printing and embossing can be difficult to visualize, especially when the project calls for both. It can be very expensive and time consuming to modify a design once the die and its matching counterforce has been created. Examples of previously created work, line drawings and other visual aids, allow the customer, printer and the print finisher to understand the client’s requirement.
Foil stamping and or embossing are a fantastic method of making any project more elegant and striking. Although the processes can be complex and detailed, early and good communication between the printer and print finisher from the project design phase will minimize problems and help keep production cost lower and on schedule.
Hot Stamping and Embossing
The terms “Hot Foiling or Foil Stamping” are universally used to describe the transfer of a colour coating from a carrier foil using heat and pressure, to a substrate. Gold, silver and other metallic colours are the most common, but are by no means the only options available in foil printing. Other colour options include gloss and matt clear foils, tints, gloss and matte pigments, pearls and special effect foils like holographic, wood grains and if the volumes are sufficient, specials. Designers can add detail, shape and form producing unbeatable quality and visual appearance by combining foiling with other finishing techniques like embossing, refractive etching, die cutting and so forth.
Blind Emboss – This example was produced with a sculptured die. This type of die produces images with extremely intricate detail.
Tint Foil – This technique adds a light tinted foil on to the embossed area.
Gloss Foil – This foil applies a bright, shiny surface on the embossed image.
Multi-Colour Foil – This image uses two foil colours to bring out a high level of detail in the embossed image.