Screen printing is a highly effective and durable method for customising blank apparel. At Done Print Co, we specialise in small to medium-scale screen printing runs, offering high-quality prints on a range of garments. In this article, we break down the entire process, from colour separations to the final finishing touches.
Colour Separations, Artwork Preparation and Film Positives
Before any screen printing begins, the artwork must be prepared for the screen set-up process. These two steps are the foundations of the process. If there are errors at these two stages the final print will likely turn out looking rubbish. We use a mixture of Adobe Photoshop and Illustrator to create colour separations. Colour separation is the term given to the different colour layers in a design. During this process each colour is isolated into individual layers. These separations are then printed out onto acetate films, which are called film positives. These films behave in the same way as negatives in analog photography. However, in screen printing, artwork is printed in the positive as opposed to photography which is all done in a negative format. Hence the name film positive or possi for short.
Things to note:
When preparing digital artwork, the design has to be set at a 1:1 scale with a minimum resolution of 300dpi.
Differences between Vector & Raster Artwork: Vector artwork (created in Illustrator) is ideal for sharp lines, solid spot colours and scalability, while raster artwork (Photoshop) is used for designs with gradients, textures or photographic elements. That said there are always exceptions to the rule and over the years there has been a lot of development in these programs which allow for a lot of cross over use.
Halftones and Simulated Process Printing: For photographic, textured and tonal images, halftones (small dots varying in size) are used to replicate shading and depth. We primarily use Photoshop to create halftone patterns making sure the dot size, or frequency, is matched to the screen mesh size, usually 77T or 90T meshes are used. As a rule of thumb, the smaller the dot the higher the mesh count.
Under-base Application: On darker garments, a white under-base is printed first and the colours are then printed very precisely on top. This is to ensure colour vibrancy of the colours. This layer counts as a colour separation and needs to be created along with the other separations.
Film Positives: It is very important to have a very opaque ink deposit when printing off the acetates. We use an Epson Eco-Tank inkjet printer which allows us to use a special black-out ink that has a very opaque finish, perfect for exposing the screens with.
Screen Set-up and Choosing the Right Mesh Count
Once the artwork is prepared, individual screens are coated with a light-sensitive emulsion. One will be use for each colour layer or separation. The choice of mesh count is critical to achieve a desired print quality or effect:
Low Mesh Counts (24-43T): Used for specialty inks like puff ink or glitter, allowing for a heavier deposit.
Medium Mesh Counts (55-64T): Ideal for standard plastisol and water-based ink applications, these are the most commonly used screen mesh counts for garment printing.
High Mesh Counts (77-90): Best for fine-detail prints and halftone images.
Once the screens are coated with the light-sensitive emulsion, they are left to dry in a light safe environment. Once dry, the film positive is attached to the underside of the screen mesh and placed on an exposure unit, which uses a UV light source to activate the light-sensitive emulsion on the screen mesh. After the screen has had sufficient exposure to the UV light, it is then placed in a washout booth and soaked with water. The area of the mesh where he film possi sat will not have been activated by the light and is broken down by the water. It eventually washes out to reveal the design. Hey presto and we have a screen with a design on.
Blank Garments
The type of blank garment greatly affects the final print. Key considerations include:
Fabric Composition: 100% cotton is best for plastisol and water-based inks, while polyester blends require a special blocker ink printed as an under-base to prevent dye migration.
Garment Fit and Weight: Different brands offer varying fits (classic, oversized, slim) and fabric weights (lightweight, midweight, heavyweight).
Sustainability Options: Organic cotton and recycled polyester garments are available for eco-conscious printing.
There are many options available in todays market. You can learn more about the different blanks we use by clicking this link.
Ink Selection: Plastisol, Water-Based, Discharge and Additives
Choosing the right ink is crucial for achieving the best results and is often determined by the fabric type and or design specifications:
Plastisol Ink: The most common ink type, known for its durability and vibrant colours. It sits on top of the fabric, providing a slightly raised feel.
Water-Based Ink: Ideal for a soft-hand feel, water-based inks penetrate the fabric, creating a more breathable print.
Discharge Ink: A type of water-based ink that removes the garment’s dye and replaces it with a coloured pigment, offering a soft and vintage look on dark fabrics.
Additives: Additives such as puff, suede and soft-hand can be added to the inks to change the inks structure, look and feel. They add a different dimension to the final print aesthetic.
Pantone Matching: Getting the right colour can make or break a design. A mixing system is essential for any professional studio. It'll allow you to pick from thousands of colours and mix them with only a few.
Speciality Inks: such as metallics, glitter, reflective and glow in the dark are really cool inks to use if a unique effect is required.
Curing the Ink
After printing, the ink must be cured at specific temperatures to ensure it sets properly. If the right temperature and dwell time isn't achieved, the ink will break down when the garments are washed.
Plastisol Inks: Require temperatures around 160-170°C, with exposure times between 1-2 minutes for a full cure.
Water-Based Inks: Typically water-based inks cure at 160-170°C, however they often require a longer exposure to the heat to ensure all the water is evaporated from the ink, usually between 2-3 minutes.
Flash Drying Between Layers: For multi-colour designs, each layer is flash dried before applying the next colour, unless printing wet-on-wet. The flash cure temperature is between 150-160°C, with short exposure times between 5-10 seconds. It is important not to fully cure the ink when flash drying.
Manual & Automatic Printing Presses
The actual printing is carried out using either a manual or automatic press, also known as a carousel:
Manual Screen Printing: Ideal for small runs and sample printing, a lot of skill and experience is required to operate a manual press with efficiency and high quality output.
Automatic Screen Printing: Best for higher volume orders where speed and precision are required. Automatic presses can be operated at a much faster speed than a manual press and often require more than one person to operate them.
For both press types, the set up and printing process is the same: each screen is aligned into the presses print heads, ink is applied to the screen, and a squeegee is used to push the ink through the screen onto the fabric. With multi coloured designs, it is essential to register each screen precisely to one-another to ensure all the layers align correctly when printed. The order in which the layers are printed is important too. The white under-base is applied first, followed by the layers that have the least amount of print area first and finishing with the layer that has the outline, or keyline. The keyline is the layer that holds the design together and gives it it's structure.
There are always exceptions to the rules, which is why screen printing is not always straight forward and it takes a tremendous amount of practice and skill to consistently achieve good results.
Finishing Touches: Relabelling, Folding & Bagging, Product Shots
To complete the production process, additional finishing touches can be done to enhance the final product’s presentation:
Relabelling: Custom neck tags (screen-printed or woven) replace the standard manufacturer's labels for a fully custom look.
Folding & Bagging: Garments can be neatly folded and individually bagged into retail-ready packaging.
Hang Tags: Branded card tags attached to the garment with brand and garment information complete a premium and professional look.
Product Shots: These are essential if the product is going to be sold online. They need to be clean and detailed to appeal to customers.
Conclusion
Screen printing is a meticulous process requiring technical expertise at every stage, from artwork preparation and screen set-up, to ink selection, press set up, printing and finishing touches. To ensure a high quality end product, each step of the process is as important as the next. At Done Print Co. we make it our mission to focus on the details at every stage to print garments that meet the highest quality standards. Whether you’re a clothing brand, music artist, or a business looking for branded apparel or workwear, our team is here to bring your ideas to life with care and precision.
For more information or to start your screen printing project, get in touch with us today!
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