Over the years, many products across many industries have had one or more images or text printed on them. Manufacturers used various printing processes, such as screen printing and pad printing, to transfer these logos and texts onto products.
This article provides a detailed guide to the screen printing process, including a step-by-step analysis of the process. You will also learn about the different types of screen printing, their applications and a comparison between screen printing and digital printing.
What is screen printing?
Screen printing is a traditional post-processing technique in which ink is pressed through a stencil fabric onto the surface of a substrate to obtain printed designs. It is also called screen printing or screen printing. This process is now widely used in various industries because it is compatible with different materials, can be repeated indefinitely and the designs have high color brilliance.
Additionally, screen printing produces a thicker ink print than most printing methods. Although manufacturers typically use screen printing on plastic and fabrics, you can also print on other materials such as plastic, ceramics, glass, etc. using special inks.
Screen Printing Process: A Step-by-Step Guide
Here's a breakdown of the screen printing steps:
Step 1: Draft creation
The first thing you need in the screen printing process is the original image or text from which the printer will make copies of the design. Prints of the selected design or pattern are then printed onto a clear acetate film.
Step 2: Select and prepare the mesh screen
The next step is to choose a screen for screen printing. However, it would help if you chose a screen based on the material or fabric type for printing and design intricacies. Then cover the screen with a layer of light-sensitive emulsion.
Step 3: Expose the emulsion paint to a light source
Place the acetate film with the motif on the mesh screen and expose both to strong light. This helps harden the emulsion paint. If your design contains multiple colors, you will need to use a different mesh screen for each paint color.
Step 4: Prepare the stencil
The area of the screen not covered by the printed design will harden over time, while any pieces of emulsion that have not been hardened by the concentrated light will be removed. This creates an excellent impression of the desired design on the mesh screen. The screen is thoroughly dried after washing while the stencil is prepared for later use.
Step 5: Prepare for screen printing
Align the mesh with the design using screws in the press. Typically, manufacturers use manual and automatic presses. Therefore, an automatic printing machine is the best option if your project requires multi-color printing. The fabric or any other material to be printed is placed on a printing plate under the screen.
Step 6: Print the drawing
Lower the canvas to get closer to the fabric while pouring the paint onto the canvas. Gently press the screen paint onto the object using a squeegee. The ink forms the impressions of the design on the fabric as it passes under the screen on the material. If you are printing multiple objects, you will need to place a new object or substrate under the screen and repeat the process.
Step 7: Heat Curing and Finishing the Print
The paint transferred to the piece dries completely with a hairdryer. After drying, it is necessary to wash the final product and check for residue before sending it to the market. You also need to wash the sieve with chemicals and prepare it for further use.
Typical screen printing equipment
Now that you know how screen printing works, let's look at the typical equipment used in this process.
1. Printers and films
A printer that can produce designs on the stencils is first on the list of things you need for custom screen printing. The printer prints the desired designs on transparent films, so-called acetate films. You will need to use a different acetate sheet for each color and later create the stencils.
2. Mesh Screen
It is the next most important material in screen printing. You need to put the transparent film on the screen to print the stencil. Screens were originally made from silk threads, and today many options are made from polyester fabric. Furthermore, the thread count, thickness and texture of the canvas determine the quality of the final print.
3. The paints
The inks or pigments used in screen printing play a crucial role in the different options. There are special inks for fine screen printing that achieve brilliant effects in the final products. Printers often use textured inks, puff inks, or glossy inks to give their prints a unique look.
4. Extractor
Squeegees are simple rubber blades attached to a plastic or wooden handle. These blades push the ink across the screen until it reaches the printed object. The squeegees used in screen printing are available in a variety of designs. In general, the screen frame often determines what type of squeegee is used.
5. Press
The printer is an essential tool that keeps the screen in place between prints. Allows you to change the objects printed under the screen.
6. Belt dryer
The ribbon dryer helps heat the ink to a temperature that ensures the longevity of the print and protects it from fading or cracking.
Types of screen printing process
There are different screen printing processes that produce different surface results. Therefore, it is best to know the different procedures to find the best solution for your product. Here are common screen printing techniques.
Grayscale printing
This type of screen printing is an impressive technique for printing colorful images as solid halftones or grayscale. However, prints appear very detailed when there are more dots in the halftone. This process is different from a black and white process. Extracts only grayscale CMY or RGB color scales. Grayscale printing is a low-cost screen printing process generally used to print black and white designs on fabrics.
Special color printing
Spot color screen printing is the most commonly used technique by product manufacturers and designers. The primary colors of the ink are used by printing them onto the screen stencil. The spot color technique is simpler than most screen printing techniques and produces a solid, bright spot of color. It's a perfect option for printing on hoodies, jackets and t-shirts.
CMYK (4-color printing)
CMYK or 4-color printing is the most complicated type of screen printing. Four basic colors are generally used: black, magenta, cyan and yellow. The combination of these colors creates the desired tones. Although you can mix colors manually, it is recommended that you mix them automatically for best results.
Duplex printing
Duotone printing combines two halftones to print the same image in two colors. The first black halftone is printed with black ink, while the second halftone uses colored ink. This printing process is identical to sepia photo printing. Provides an artistic and elegant effect.
Halftone printing
In halftone printing, individual colors are printed in gradients. The entire process uses a single color of ink, usually halftone, so when viewed from a distance, the print results in a different shade. This technique is suitable for multi-color printing results without the need to print multiple colors.
Simulated process pressure
This technique combines spot color printing and four-color printing. Because the mock printing process is ideal for both darker and lighter tones, it is versatile and well-known among manufacturers and designers who need to create photorealistic print details.
Advantages and disadvantages of screen printing
Advantages of screen printing
Screen printing is an efficient process with enormous benefits in several sectors. Here are some of the main benefits of the screen printing process:
Simplified process
The printing process, whether manual or automatic, is relatively simple. Most importantly, the tools needed to print are neither complicated nor too expensive to replace.
Multifunctional/versatile method
The screen printing process is compatible with different products regardless of shape, size and material. This process allows you to print flat and form objects with irregular or complex shapes, such as spherical surfaces. This process also allows the use of multiple colors in printing.
Long-lasting projects
This process uses high ink density to achieve a clean, colorful design, ensuring the longevity and quality of the printed design. The ink melts into the fabric ensuring it does not crack or fade quickly.
Most importantly, the application of certain coatings and additives makes the paint resistant to moisture, UV rays, chemicals and scratches. This makes components produced by the screen printing process suitable for outdoor use and in aggressive environments, without sacrificing quality.
Efficiency and speed
Unlike other printing techniques, screen printing is fast and efficient as long as the screen printing is completed. It is the ideal option for projects where the design needs to be repeated.
Disadvantages of screen printing
Although screen printing is a versatile technique with many advantages, the process also has disadvantages. Here are some of them:
High setup costs
The initial cost of setting up screen printing technology is high. Therefore, it is best to outsource products that require screen printing to a specialized supplier.
More color variations, more costs
Screen printing can only produce one color at a time, making the process relatively slow and difficult with multicolor printing. The process costs more because you have to create a new screen for each color. Furthermore, screen printing is highly prone to color registration defects, resulting in higher costs and product wastage rates.
Screen printing applications
Screen printing technology is versatile and delivers impressive results across multiple industries. Here are typical screen printing applications.
Electronic printing
The electronics industry benefits from screen printing technology as demand for electronic devices increases. This printing process is efficient and reliable due to the best printing methods, materials and equipment.
Textile printing
Screen printing is a well-known technique in the textile industry. This industry benefits from this technique in t-shirt printing and various image designs. Most importantly, custom screen printing is available in a variety of print configurations, allowing for greater flexibility when printing on fabric.
Glass and ceramics
Screen printing technology is of great help in the production of glass and ceramic items with printed images and texts for consumer and industrial applications. This printing technique is unique as it helps this industry overcome several significant challenges in glass decoration.
Stickers and displays for shop windows
Screen printing is ideal for branding and displaying information and window stickers. The bright colors of screen printing make this print a selling point in most businesses and workspaces.
Screen printing versus digital printing: the basic differences
Screen printing is relatively primitive compared to digital printing. Digital printing is an automated (computer-controlled) technique in which images and text are printed on desired surfaces using printing machines. This process involves creating a design or artwork on a computer and converting digital images into prints on any material. Digital printing does not involve all the mechanical steps of conventional printing.
This section explains the basics of screen printing versus digital printing so you can easily choose the best technique for your printing project. Here are the main differences:
Setup time and costs
The screen printing process requires you to create and configure each screen before printing. You will also need stencils and other tools for the process. These screens are normally discarded after each design is printed. Therefore, unlike digital printing, screen printing involves high setup costs and screening fees.
Color rendering
If color is a priority in printing, screen printing is the perfect choice. This is because ink uses spot colors, whereas digital printing machines use a four-color CMYK technique, resulting in a limited color palette. As a result, digital printing machines cannot achieve some of the vibrant colors that screen printing offers, including greens, reds, grays and oranges.
Crowd
Screen printing is ideal if you are spreading setup costs across multiple products. Screen printing allows you to complete more prints per hour faster than digital printing machines. Therefore, large print runs become cheaper, regardless of setup costs. At the same time, short-run printing with digital printers is more economical due to low or no setup costs.
Paint adhesion and durability
It is known that the inks used in screen printing adhere to various surfaces (e.g. glass, wood, plastic, metal, etc.). Digital inks have been around for a while and are available in different series that can adhere to different substrates. However, these digital inks are more expensive than the ink used in screen printing.
Additionally, screen printing on metal is more weather resistant and durable than digital printing. You can also apply a UV-resistant clear varnish to the substrate using screen printing to further protect the printed image. Unfortunately, there is no clear digital finish available for digital printing.
Concluding
Screen printing is a reliable technique for printing images and text on your products made from various materials. Consider using this technique as it is flexible and straightforward. However, it would be helpful to understand the basics of the process and its types to know how well it fits into your next project.
Common questions
Can screen printing crack?
Screen prints may fade, crack, or disappear completely. However, you can cure your screen printing products to ensure ink adhesion and durability.
Can I remove the screen print?
You can remove screen prints on products with nail polish remover or acetone. Acetone is a chemical ingredient often found in nail polish remover. It loosens and removes old and cracked screen printing patterns efficiently.
Which fabric material is best for screen printing?
Cotton and cotton blends are the ideal fabric choice for screen printing. Cotton thread has excellent multifilament properties, which means it can absorb dye better than synthetic fabrics.
