What is Foil Stamping?
Foil stamping is the application of metallic print and foil on materials such as plastics, paper, and card, using heat and pressure.
It can be used to create a variety of textures such as metallic, matte, glossy, and holographic textures on the medium.
This printing process of stamping is different from pad printing or silk screening, and is ideal for printed products with dark coloured surfaces as it does not involve the use of any ink and is thus not affected by the colour or texture of the medium.
This printing process foil stamping has been around since 19th centures and has been used for creating products like holiday card, baby announcement, scratchoff foil, wedding invitation ideas, save the date cards, business cards, presentation folders, book cover, etc.
How Does Hot Foil Stamping Work?
Foil Stamping involves the use of a specialised multi-layered foil. Typically, the different types of layers in the foil are:
- A polyester carrier layer,
- A release layer,
- Lacquer layers,
- Image layers,
- Metal layers (gold leaf or gold silver leaf or foil color), and
- An outer adhesive layer
During hot foiling, heat and pressure are applied to the foil, which is pressed against the medium supported by a plate or cylinder.
The adhesive layer in the gold foil or silver foil is activated by this heat and pressure, and the release layer melts, attaching the machine hot foil to the medium.
The machine used for this hot foiling process is called a hot foil stamper /hot foil stamping machine. It could either be an independent, stand-alone machine or be connected to a printer or other such equipment.
The dies used in the hot foil stamper are usually made of brass that is etched or engraved manually or through other systems.
What are the Applications of Foil Stamping?
Hot foiling, or hot stamping, is used for the decoration of a wide range of products. It is also used as an anti-counterfeiting method.
It is widely used in the finishing of packaging products such as food, medicine, beverages, as well as high-end luxury products. Foil stamping is also used on currency notes, artwork, as well as for designing greeting cards, wedding invitations, book covers, on paper stock, etc.
What are The Different Types of Hot Foiling Machines and How Do They Work?
Commonly, there are three different types of hot foiling machines, depending on the type of operation.
- Round-flat, and
Flat-flat Foil Stamping Machines:
The foil dies are either attached to a honeycomb-shaped plate for variable positioning, or on a flat metal plate if the positions are fixed. The medium and the foil are brought in between the plate and a counter plate that is fixed under it.
In the case of embossed foiling, the lower plate consists of projections to form the embossed design when the plates are pressed together.
The main advantage of flat foil stamping is that it is easy to set up and the tools and parts for it are easily available in the market.
Round-flat Foil Stamping Machines:
Round-flat foil stamping machines have a rotating cylinder in place of the stationary flat counter plate present in the flat-flat foil stamping machine.
Pressure is applied horizontally across the rotating cylinder and the foil is thus pressed against the medium, transferring the foil design onto it.
The advantage of this type of foil stamping machine is that they are a perfect solution for smaller jobs with few pieces.
Round-round Foil Stamping Machines:
These machines work on a similar principle as printing presses. Both the sides of the machine have rotating cylinders that rotate in opposite directions. The foil, as well as the medium, are brought together between the two cylinders, and the cylinders are pressed together to apply pressure.
This type of foil stamping machine can rotate to very high speeds and can be used for very intricate designs. It is perfect for producing highly complex foiling effects on the medium.
What are The Two Types of Foil Stamping Methods?
The two main types of hot foil stamping methods in use today are the traditional hot stamp method and the digital foil printing method.
Traditional Hot Foiling:
In the traditional foiling process, the design to be stamped is first engraved or etched into a metallic plate (known as a foiling die or die cut).
Using heat and pressure in the foil printing machine, the design is then transferred onto the print surface (the surface that needs to be foiled), from the die.
In case there is more than one coloured design that needs to be foiled, separate metal dies need to be prepared for each colour. The dies are then applied to the medium one by one in order to achieve the final result.
For embossed designs, a special effects foil die needs to be prepared that can produce that sort of effect on the medium.
Digital Hot Foiling:
A digital hot foiling printing machine is similar to a traditional hot foiling machine in their outward appearance. However, the difference between them lies in the way the foil is attached to the surface of the medium.
In digital foil stamping, the graphic design is digitally printed onto the medium using a specialised foil that sticks to the medium. There are no dies that are separately prepared in this method.
Digital foiling is very similar to conventional ink printing methods. It does not require multiple runs of the machine in case there is more than one colour or design that needs to be foiled.
Types of Foils Used in The Foil Stamping Process
In order to achieve various kinds of finishes and designs, different types of custom foil materials are used.
Some commercial foil materials used in the foil stamping process are
- Metallic Foils,
- Pigmented Foils,
- Pearlescent Foils,
- Special Design Foils, and
- Scratch Foils
1. Metallic Foils:
These are the most common types of foils used in the foil stamping process. They give a classic metallic finish to the design and are usually available in gold and silver colours, although other colours are also used.
2. Pigmented Foils:
Pigmented foils produce a matte or glossy non-metallic finish on the design. They are very versatile and can be used on a variety of medium materials from paper to plastic. They can be of any desired colour.
3. Pearlescent Foils:
Pearlescent foils add a beautiful pearly shine to the design. They are mostly used on greeting cards and wedding invitations and are available in both transparent as well as translucent finishes.
4. Special Design Foils:
These foils are of many different types (such as holographic foils) and are used to produce a wide variety of patterns on the medium. They can produce special effects such as holographs, stripes, sparkles, and other patterns for custom printing.
Holographic foils have a three dimensional or rainbow colour design and are especially important. They are used to prevent counterfeiting while producing bank notes, ID cards, credit cards, and other high-security items.
5. Scratch Foils:
These foils are designed to be easily scratched off by means of a coin or fingernail. They are mostly used on items such as lottery tickets and phone recharge cards.
The foil print on the paper or card is not permanent and can be scratched off easily. This is why they are perfect as a temporary cover for highly sensitive information.
A foiling die is prepared for each design depending on the pattern and colour/ types of foil that needs to be used.
There are three different metals that are used to make foiling dies, depending on the cost and application.
1. Magnesium Dies:
They are usually made from magnesium, which is a cheap and soft metal that can be easily manipulated into different patterns. They are light in weight, take less time to etch, and heat up very quickly.
However, they do not last very long and get damaged after a few thousand runs on the foiling machine.
2. Copper Dies:
Copper dies are more expensive than magnesium dies. They take longer to etch and are heavier in weight.
They are more durable than magnesium dies and can produce high-quality designs that last for a longer period of time.
3. Brass Dies:
These are the most expensive, and undoubtedly, the sturdiest of all three metals. They are tough and last for many runs. They are usually prepared through CNC systems, which basically use different sized drill bits to etch the designs on the die.
The dies are prepared using a process called acid etching. Each die can be reused multiple times and stored when not in use.
4. Other Types of Foil Dies:
Apart from the above-mentioned dies, there are also dies made of steel and dies made of rubber. These types of dies are created for specific purposes.
There are three other types of dies that you need to know about:
Single Level Die:
A single level die is usually just referred to as a foiling die, and is the most common die that is used in foiling. The die has one surface that is plain and the other surface that stamps the foil.
This die has a texturized foiling surface.
This die allows you to foil and emboss a pattern in a single run.
These are all the important things that you need to know about foil stamping, the different steps involved, and the components.
We hope we have made the process simple for you to understand. For more information on how you can use foiling in your projects, contact Unipipes Malaysia!