The printing industry has undergone rapid change in the past decade. Digital technology is revolutionizing the printing process and pushing the boundaries of conventional printing. In such an exciting time for the future of the industry, it’s important to know where it started and just how far we’ve come!
Did you know these important dates in the history of printing?
A Brief History Of Printing
Johannes Gutenberg’s improvised a movable type press with an alloy of lead, tin, antimony, copper, and bismuth. His innovation led to the famed printing press that spread throughout Europe during the Renaissance. It is still considered one of the most critical changes in history.
Different Types Of Printing Techniques
Since Gutenberg brought the movable type press to Europe, different types of printing techniques have evolved over the centuries. Digital printing is a large corner of the market!
Q: What is Digital Printing?
A: Digital printing is the process by which digital images are transferred onto mediums (paper, fabric, plastic, etc.)
Digital printing doesn’t require plates or stencils like conventional printing. That makes for a lower cost overall, as clients are free to order smaller volumes or even varying the design for less.
Another interesting characteristic of digital printing is that ink deposits in a layer on top of the medium instead of being absorbed. That is why most digital printing is with toners!
Inkjet printers are the most common today, especially when printing books, posters, and signage. This type of printer is also the best option when low volumes of printing are needed and often found in businesses and individual homes!
The printer works by spraying ink droplets through a nozzle onto the medium in one of two ways. In continuous inkjet (CIJ) printers, the ink is pushed through the nozzle continuously onto the medium or collected into a reservoir for future use. In contrast, drop-on-demand (DOD) printers only release ink when it’s needed.
Large format inkjet printers are in professional print shops and industrial locations. Large format and industrial inkjet printers are now being used for product marking, packaging, tiles, and even electronics!
Latex Inkjet Printing
Latex ink is one of the latest developments as printing gears towards eco-friendliness. It involves ink pigments that use latex as a carrier with water remaining a significant component. As it does not cause harm to both health and environment, latex inkjet printing is ideal for printing indoor signage, banners and other materials.
Aqueous Inkjet Printing
Aqueous Inkjet printing is a great eco-friendly printing option for indoor projects. It relies on color pigments that are dissolved in water and then pushed through a nozzle onto the medium. These printers are ideal for office spaces as there aren’t any odors. That makes them incredibly popular and probably explains why 78% of industrial printers sold in 2012 were aqueous inkjet printers.
The only downside to this printing type is that a special coating is needed for the ink to bond to the medium.
Solvent printing is the go-to choice for outdoor materials, particularly signage. The printing process involves mixing color pigment with a solvent. When the ink transfers onto the medium, the solvent dries off and leaves the ink behind. This printing method is highly durable, which makes it the favorite for outdoor purpose.
One major drawback is that traditional solvent inks are not environmentally friendly, and the odor that is produced makes it a lousy choice for indoor projects.
Technological advancement has also addressed the issues found in traditional solvent printing! Eco-solvent printing is the same process as a traditional solvent. However, the solvent is eco-friendly and completely biodegradable! In addition:
It is odorless
No harmful chemicals
No toxic fumes
Laser printing first came about in the 1970s and uses an electrostatically charged cylinder with a laser beam. The cylinder is exposed to the laser at specific areas that make up the image, which charges the coating and attracts toner particles.
Super cool sciencey stuff, right? It doesn’t stop there!
Next, the toner particles that form the image are directly transferred onto the paper and heat fuses the image permanently. Voila! A printed image.
Laser printers used to be quite expensive, but the cost has decreased over the years. Both black and white and color printers are available on the market and are usually used commercially for mass volume printing. A great example is utility bills, court documents and transaction records.
UV Flatbed Printing
UV Flatbed printers are another of the latest digital advancements in printing — the flatbed printer prints on large, flat surfaces with a special ink that dries instantly in UV light. This printing method is also eco-friendly, as it doesn’t use any solvents.
Another exciting perk of UV flatbed printing is that because of the instant drying of the ink; the printing is incredibly vibrant. That is because the ink doesn’t have time to saturate. Additionally, it allows for the ability to print multiple layers, including clear! That means contour effects can be printed directly onto the material.
Because of the quick drying and ability to accommodate large, flat objects, UV flatbed printing is often on fabric, wood, acrylic and even metal.
Thermal printing uses no ink. Instead, this technique uses thermochromic paper that changes color in high temperature. Electric current heats the thermal printer head and the paper underneath turns black.
Thermal printers are usually used in kiosk and retail applications. They are portable, energy efficient and require minimal maintenance. However, thermal papers may be sensitive to intense heat, and printed text could fade if continuously exposed to light.
Dot Matrix Printing
Dot matrix printing uses impact printing technology. The printer head strikes on an inked-ribbon onto the paper, making closely spaced dots. These dots then create characters.
Dot matrix printers were popular in the ’90s because of durability and low cost. The printer can print in continuous sheets, which is perfect for invoices. Also, carbon copies can also be created with the printer.
Dye Sublimation Printing
Dye sublimation printing efficiently produces photo-quality results. Users print images on polyester fabrics, glass, ceramics, metals, and other materials. Instead of printing directly on the materials, dye sublimation tech prints the pictures on a special transfer paper with special aqueous or solvent ink.
A heat press is then used to transfer the images on the paper into the final material by placing the transfer paper on top and then applying heat. At high temps, the inks vaporize and bond with the medium, which does not fade even after washing.
Although dye sublimation is a relatively new technology, it is a preferred printing technique thanks to its quality and durability. However, dye sublimation inks only bond with synthetic or polyester material, limiting its range of printable materials.
Flexography printing evolved from printing press technology in the 1890s. This type of printing revolutionized printing at the time, as it allowed for the ability to print on a wide range of mediums. Everything from paper and plastic to fabric and cardboard can be printed .
Some quick facts about flexography printing:
Is ideal for mass printing because of quick-drying ink
Supports a broad range of inks, from water-based, solvent, EB curing inks, UV and more.
Low maintenance and operates at high speed
Perfect for long printing runs.
So how does it work?
The printer has a fountain roller which picks up ink from the ink tray and transfers to a set of plates. The plates are secured on the plate cylinder and then transfer the image over to the medium. The medium is fed through the plate cylinder and the impression cylinder, which maintains a constant pressure to make sure the image transfers well.
As flexography printers can operate with minimal interruptions, it is highly used in printing packaging materials such as labels, corrugated boxes, shopping bags, and beverage cartons. Manufacturers often save time in production as high-end flexography printers can print up to 2,000 feet per minute.
After falling out of popularity in the ’70s, letterpress printing has seen a revival. This method evolved from movable type printing that was created in the 15th century.
Here’s how it works:
Multiple pieces of movable types are assembled to form the text
This type is turned into a form that is fitted on the press
The press is manually inked, and paper is fed through
Modern letterpress printing has evolved slightly and incorporates digital images transferred onto photopolymer plates. These plates are then fixed into a press machine and ink is applied manually.
The ink is transferred onto the page with a deep impression, creating a look that is unique to letterpress.
Letterpress is perfect for specialty items with a hint of elegance, such as gift boxes and wedding cards. Because letterpress printing is time-consuming, primarily when it uses multiple colors, it is often a specialty method of printing.
Offset Lithography Printing
Offset printing, a type of printing method for physical publications, is also known as offset lithography printing. The term ‘offset’ implies that the image is not directly transferred from a printing plate to the substrate. Only flat-surfaced material can be in offset printing.
An offset printer consists of three main components, the plate cylinder, offset cylinder and the impression cylinder. The printing process takes advantage of the fact that water and oil do not mix. That enables both image and non-image area to exist on the same plane in offset printing.
The plate cylinder, often made of aluminum, is inked by the ink rollers before the water roller dampens the non-image area. The inked image area on the plate cylinder transfers onto the rubber offset cylinder, before being impressed onto the substrate. The substrate is heated at a high temperature to prevent smudging from the wet ink. The substrate is then passed through a series of chill rollers to be cooling down for the inks to set in.
Offset printers are also available in different setups, depending on the publishing requirements. Some installations replace the impression cylinder with a blanket or offset cylinder. This setup allows both sides of the substrate to print on simultaneously.
Besides the different setups, offset printers are also differentiated by sheet-fed and web-feed offset. Sheet-fed offset printers require a single sheet of paper to be fed to the press at a time while web-feed printers can print on a continuous roll of paper. Printing speed is also a key advantage of offset printers, with modern presses capable of printing up to 18,000 sheets in an hour.
Rotogravure or gravure printing found new life in the packaging industry after experiencing a decline in the 1960s. It is a type of intaglio printing, where images are incised into the surface of the image carrier. This form of printing is widely used for creating wallpapers, gift pouches, and packaging in high volume.
The mechanism of rotogravure printing consists of two primary components; an impression cylinder and the engraved roller. The first step in preparing for rotogravure printing involves etching the metal roller with acid in according to the images. As a result, the engraved roller will have cells of varying depths on the surface, which will be holding the inks during the printing process.
Rotogravure is a CMYK printing process, where each roller only prints in a single color. The depth of the cell ultimately affects the intensity of the color, which made precision a crucial factor when the metal cylinder is being engraved.
During the printing process, the engraved cylinder will rotate, and the cells picked up the ink. A blade is used to scrape off inks from non-image area. The inked cells are then transferred to the substrate which passes through between the engraved cylinder and the impression roller.
As the engraved cylinder is capable of printing millions of images before it wears off, rotogravure has become a preferred option for long runs of printing. Due to its high setup cost, rotogravure is not suitable for small volume printing. In such cases, photogravure, a variant where etched copper plates to a cylinder may be more suitable.
Gravure printing is preferable when a broad density range of a particular ink is required. It is a popular printing method for fine art and photography reproduction. The disadvantage of rotogravure is that the printed images are a combination of dots which may be visible under close inspection.
7. Screen Printing
Screen printing uses a mesh to transfer an image to a substrate. The primitive form of screen printing was first recorded in the Song Dynasty, China before spreading to Asian countries like Japan and evolved. It was also known as serigraphy and where silk meshes are used, silkscreen printing.
Modern screen printing involves using a mesh that is made of synthetic polymers such as nylon. The mesh is spread over aluminum or wooden frame to create a screen. A photosensitive material is then coated over the mesh, and the image area is masked before the screen is exposed to ultraviolet light.
Areas that are exposed to UV light are hardened, and those that are masked are washed off by water, creating openings where inks would eventually pass through. The screen is then placed on top of the material to be printed, and a layer of ink is applied over the mesh.
A squeegee is then used to press the mesh against the object than the ink on the opening will rub against the material. When the squeegee is released, the ink will transfer from the mesh to the material.
Screen printing can be applied to a broad range of materials, such as glass, metal, paper, and fabric. It does not require the printed material to have flat surfaces, and various inks can be used for different substrates. Screen printing is a type of printing method commonly used to screen-print T-shirts and glasses. It is also used extensively in printing protective resists area on electronics printed circuit boards
8. Pad Printing
Pad printing is an effective printing method to transfer a 2D image into a 3D object. This type of printing technique has become famous after World War II after it was used to print on curved watch surfaces. Today, pad printing is used to print difficult items in industries like medical, electronics and cosmetics.
A relatively modern process, pad printing uses a silicone pad to transfer the inks onto the surface of an item. A pad printing machine will secure both the silicone pad and the object to print. It then moves the silicone pad into the ink plate, which is engraved to the desired image to be printed.
The silicone pad would be pressed to the ink plate to be inked. Then, the silicone pad will be lifted and pressed against the surface of the item, which often is in three dimensional. As the silicone pad wraps around the item, the ink will be firmly transferred to the surface.
Pad printing is a versatile printing technique as it could be used on items of various materials and shape. Delicate items which can’t be printed with conventional methods will have no problems with pad printing. Solvent-based inks are used in printing, and they are usually quick-drying.
Some of the factors that pad printing is being favored for in-house operations is its relatively low cost and ease of setting up. It can produce high-resolution print when compared to other print methods.
Modern Revolutionary Printing Technologies
Digital technologies continue to make breakthroughs in recent years and have caused new printing technologies to emerge. The use of intelligent electronics and new materials have blurred the boundaries of conventional printing. Here are some different types of printing technologies that will redefine the industry.
1. 3D Printing
3D printing is a type of modern printing process that turns a digital model of an object into a three-dimensional prototype through an additive manufacturing process. While 3D printing was already available in the 1980s, it wasn’t until recent years that the innovation in 3D printers has made it more affordable, precise and accessible.
A 3D object can be printed from a CAD file or through data generated from a 3D scanner. 3D printers use materials like plastic filaments to create thin layers to construct the object. The filaments are melted with heat at the print nozzle before being printed on the printing base. Although plastic filaments are commonly used in 3D printing, materials like metal, ceramic, and nylon have also been used in specific applications.
The commercialization of 3D printing has positively impacted various industries. It has drastically lowered the cost of rapid prototyping for product-oriented companies. 3D printing has also been applied in aerospace, automotive and aviation industries, highlighting the precision and quality that can be delivered by industrial 3D printers.
2. Printed Electronics
Printed electronics define the process of producing electronics via the printing process. In other words, both conductive and dielectric materials are printed onto various substrates by an inkjet printer. That allows greater flexibility on the type and thickness of the materials, making it an ideal technique for creating electronics circuit on flexible film and paper.
As the demand for slimmer electronics gadgets like smart wearables, and IoT, printed electronics is increasingly popular thanks to its low-cost and flexible approach. One of the challenges faced by printed electronics is the need for better conductive inks, as they have a relatively lower conductivity compared to the conventional PCB manufacturing process.
We hope this in-depth guide to the different types of printing techniques has provided you an insight to the industry and the emerging trends to look out for in the future.