What is silk screen printing? Read this guide to find the answer.
Applying printed labels, drawings or writings on materials can be purely decorational.
But in other cases, it might be necessary for certain products like PCBs to indicate critical information.
So you can use the printing technique on different substrate materials and vary the inking processes to achieve unique effects.
Look at the silk screen printing process, its types, and its benefits below.
What Is Silk Screen Printing?
Silk screen printing transfers stencil designs to flat, plain materials like sheets of paper, garments, plastic, etc.
The process involves using squeegees, ink, and mesh screens to paste the designs.
Silk Screen Printing Process
The process involves these steps.
Begin by printing the design on a transparent acetate film. This printed design will help form the screen or stencil later.
An acetate film for photography
Printing screens come in different types to match various fabric designs and textures.
Once selected, coat it with a layer of light-reactive emulsion to harden when developed under bright light.
Place the acetate sheet (with the design) on the emulsion-coated mesh screen. Next, place the two under a bright light to develop and harden the emulsion.
The areas covered by the film design will remain liquid while the other sections turn solid.
After emulsion hardening, carefully rinse the mesh screen to wash away the uncovered liquid emulsion.
The process will leave an imprint or negative image that allows the ink to pass through and form the original image.
Multiple silk screen frames
This remaining part is a stencil you can use in the printing press. The printer should handle any required touch-ups or corrections to make the stencil as precise as possible.
Prepare the material to print on by laying it on a flat surface. Place the stencil on the printing press right above the material.
Printing (Inking and Squeegee)
Lower the stencil screen to the printing board above the material. Next, apply the ink with the required color above the stencil.
Use a squeegee to spread the ink across the entire screen length to push it through any openings.
Since the screen openings match the design, the ink will imprint a pattern that matches it.
A worker using a squeegee to spread ink on a silkscreen
You can use this stencil design to create multiple printed designs. And if you no longer need it, use a washing fluid to remove the hardened emulsion.
This cleaning will leave the mesh ready for reuse to create a new stencil.
If the design is multicolored, use separate stencils for each color. And you’ll have to align each screen precisely to ensure the final printed design matches the original.
Drying, Quality Checks, and Finishing
The last step is to place the printed material or fabric in a dryer to cure the layers of ink and leave a smooth print.
This finished print should undergo inspection for quality checks and washing to eliminate emulsion traces.
Types of Screen Printing Processes
You can use any one of these six screen printing techniques to produce different results.
Spot Color Screen Printing
This technique uses the ink’s stock color to print the design through the stencil. It creates a solid color spot that is deep and vibrant.
The printing process is more straightforward than the other types. So it is the most popular technique in the commercial screen printing industry.
For instance, it is ideal for fabric printing (hoodie, jacket, and t-shirt printing).
Although this process uses a single ink color, it prints the color in gradients.
This halftoning creates a different color shade that is noticeable from a distance.
So you can define halftone printing as an affordable way to achieve multi-color printing without using multiple colors.
A halftone image print
This printing method is ideal for printing full-color images in shades of gray from black to white or halftones.
And it is a cost-effective printing method for creating white and black designs on fabrics.
Plus, the image can appear more detailed if you print a halftone with multiple dots.
Duotone printing combines two halftones to print a single image using two ink colors.
But they appear as four colors in the final print. The first halftone uses blank ink, while the second is colored ink.
The combination creates an artistic effect that resembles sepia toning in photography.
Since it uses four base colors, CMYK printing is the most complex technique.
CMYK refers to the four base colors: cyan, magenta, yellow, and key (black).
You can use different combinations of these four to create any color.
Screen printing inks
Simulated Process Printing
Simulated printing combines CMYK with spot color printing to create light and dark shades.
The result is photorealistic prints that have high attention to detail. So the process is ideal for artistic applications.
Benefits of Screen Printing
Designers prefer this printing method because of the following benefits.
Creating multicolored screen prints is challenging; the resulting designs have vibrant colors.
This phenomenon is due to the thick layer of ink applied via the stencil, which creates more intense colors than other printing methods.
In addition to being vibrant, the prints created by silk screens have a textured surface because the thick ink rises above the material.
You can screen print materials like wood, glass, plastic, fabric, metal, etc.
Ideal for Reuse
One stencil can print as many designs as possible on the printing press. So you can use this process for high-volume production.
And when you’re done with the stencil design, wash off the hardened emulsion and create a new stencil on the mesh.
Silk screen prints are durable because the thick ink does not come off quickly.
Plus, you can mix the ink with some additives or coatings that make it resistant to:
- Ultraviolet light rays
A silk screen print applied on a work table
Whether done manually or automatically, screen printing is a relatively straightforward process. Plus, the required tools are easy and cheap to find.
Setting up the silk screen printing process is expensive at first.
But the operational costs afterward are relatively low. So you’ll get your money back quickly in the long run.
Silk Screen Printing Equipment
By now, you have encountered terms like squeegees, ink, and printing press. But these are not all you need.
Here’s a detailed look at all the equipment you need for this printing process.
Printers create stencil designs on transparent acetate films to create custom film-positive designs to print on your project.
Transparent acetate films hold the designs to transfer them to the mesh screen to leave the image’s negative stencil.
Mesh screens are the most critical components to use in silkscreen printing. Initially, these screens only had silk thread mesh fabrics.
Multiple mesh screens in a workshop
But modern mesh screens have polyester fabrics. It is vital to note that the mesh screen’s thickness, thread count, and texture determine the final print quality.
Silkscreen inks can be puffy, glittery, or textured to create different effects on the final print.
Other options include glue beads, discharge inks (for dark fabrics), glossy ink, plastisol, and metallic ink.
Squeegees are rubber blades that resemble those used to wipe a car’s windscreen.
They have a plastic or wooden frame to hold the rubber blade, and they spread ink above the stencil to push it through to the material underneath.
Squeegees come in different types. And the mesh screen printing frame usually determines the type of squeegee to use.
Silk Screen Printer (Printing Press)
A printing press is a tool that holds the mesh screen (stencil) firmly above the item you are working on.
It allows you to change the material below the stencil to print several pieces continuously.
Dryers cure the ink on the printed surface to prevent peeling. Also, they create smooth surfaces that don’t fade on the finished product.
A screen-printed t-shirt going into a dryer
Applications of Screen Printing
Silkscreens are ideal for printing the following items.
- Textiles (garment printing)
- Window stickers
- Medical devices
- Product labels
- Sports equipment
Silk Screen Printing vs. Digital Printing
Here’s how this other popular printing method compares to silk screen printing.
|Silk Screen Printing||Digital Printing|
|Manual process (done by hand from start to finish)||Computerized process (designs done on computers and materialized using printers)|
|Ideal for bulk orders to be cost-effective||Suitable for small and large orders|
|Produces vibrant and textured design colors||Colors might appear slightly washed out|
|Difficult to reproduce detailed images||Easy to print intricate designs|
|Can use different types of ink (requires separate screens)||Only uses ink compatible with the printer|
Silk screen printing is a versatile and reusable technique with high design qualities.
And different screen printing methods vary based on the ink used.
Although a manual process, the results are better than digital printing and ideal for high-volume production.
We hope this article has been insightful. Contact us if you need further information.