Flex Printing: The Ultimate Guide

//

Oakley Mae

Home » Blog » Flexible PCB » Flex Printing: The Ultimate Guide

Modern technology has improved every aspect of circuit design and development thanks to the application of technologies like flex printing.

Gone are the days when you would design your circuit board and outsource manufacturing from an outside company.

Unfortunately, such over-reliance on outside companies leads to unexpected delays. 

Nowadays, we have modern circuit board printers to help you design and print a PCB without involving a third party.

For this reason, we have prepared this article to guide you through the flex printing process. Keep reading to learn more. 

Table of Contents

What’s A Flexible PCB?

A flexible PCB inside a membrane

(A flexible PCB inside a membrane)

They are circuit boards that can bend or twist.

Generally, these circuit boards undergo a different design, fabrication, and functionality than rigid ones.

In most cases, it has metallic trace layers that consist of copper bonded to polyimide. 

Moreover, you use an adhesive to bond the metal to a substrate. However, you can still use other bonding methods, like vapor deposition.

And since copper usually oxidizes, we cover it with a protective layer. Therefore, solder and gold are the common protective layers we use, thanks to their environmental durability and better conductivity. 

Furthermore, for non-contact areas, we use a dielectric material to protect the circuitry from electrical shorting or oxidation.

Finally, you can use flexible circuit boards in tight spaces and develop compact electronic devices. 

What Is Flex Printing?

An inkjet printer

(An inkjet printer)

Flex printing is an approach where you capture and convert original images into different colors for various industries and applications.

Fortunately, there are modern printing machines to do this work effortlessly. Although the printers are designed to operate like inkjet printers, they only accept flexible materials. 

However, don’t confuse flex printing with vinyl printing. We’ll explore their differences below:

Differences Between Vinyl and Flex Printing

As highlighted, flex printing helps you capture and convert original images into different colors for various applications.

However, flex printing is only applicable to flexible materials.

After printing on the flex material, you can apply it to jackets, sweaters, t-shirts, or flexible boards.

Specifically, you attach flex materials to the above end products by applying heat to ensure the material is bonded to the surface. 

On the other hand, vinyl printing is the most common signature and banner printing in use today.

When using this printing approach, you send the sign maker an outline or pattern with the colors you want to use.

Afterward, they load the vinyl into a special machine to cut it into the desired pattern. 

After cutting the vinyl, you can apply it to your intended surface.

Unlike flex printing, where you attach the material to your medium using heat, vinyl printing requires an adhesive to stick to your banner or sign.

Unfortunately, vinyl is prone to wrinkling, which affects the outcome. 

Printed Circuit Board Printer

A detailed PCB

(A detailed PCB)

The traditional approach was outsourcing circuit board prototyping to your supplier.

Nowadays, we have printed circuit board printers that allow companies to develop prototypes by themselves. 

Surprisingly, these circuit board printers can make PCBs without engraving. This happens by squirting a conductive ink or a hard and flat surface.

Consequently, printing a simple 4-bit microcontroller on your cardboard is possible. Generally, the goal is to manage intelligent packaging and create smart clothes. 

PCB 3D Printer

Circuit board printers use dielectric and conductive ink to create circuit boards from scratch.

Moreover, some of them apply the application components and solder paste.

Therefore, PCB printers are an excellent asset for hassle-free prototyping. 

Surprisingly, we have seen a rapid rise in the application of 3D printers, thus accelerating endless possibilities for home production and rapid prototyping.

This means you can easily develop different models using a 3D program and later print your design in 3D. 

However, even to date, not very few people understand that they can print 3D electronics.

Some still stick to the old approach of using a soldering iron to design and develop a PCB. 

Creating Models in Your Home

A 3D printer makes it possible to create models using 3D modeling software and later print them from home.

However, 3D printing electronics are out of reach nowadays. This explains why only a few companies or individuals manufacture them. 

Diode Lasers

Many don’t know that installing high-quality diode lasers on any 3D printer is possible.

This can happen as an addition or in place of your printer’s extruder.

However, diode lasers are small and compact and have a lower power output compared to some CO2 lasers. 

Generally, 3D printing has been around for sometimes with hobbyists and professionals being the main users.

It’s only recently that we have the technology finding application in electronics like printed circuit boards. 

How Circuit Board 3D Printers Help

Generally, 3D circuit board printers combine sophisticated software, advanced nanochemistry, and precision inkjet deposition printers to guarantee rapid prototyping.

Additionally, it reduces the time you spend on prototyping from weeks to a few hours.

Surprisingly, this happens even for the most complex circuit boards. 

3D printing technology lets engineers or professional designers create and test partial boards and, where possible, change the designs.

We tried using the technology, and we guarantee that it helps save time and money.

Furthermore, it increases the overall product quality. 

Finally, apart from 3D circuit board printers offering fewer errors, they also provide high speed, resolutions, and conductivity. 

PCB Laser Printer

The best and most lasting approach to making a circuit board involves using a photoresist.

During this process, you expose a circuit board covered with photoresist paint via a mask to ultraviolet light.

Afterward, you etch the uncovered copper and slowly wash away the exposed paint. 

You then use a circuit board laser printer to import your circuit board design.

Generally, you introduce it as a bit-map image and print it out in a way resembling a paper laser printer. It can cover the whole circuit board surface, and the process will proceed line by line. 

The laser will turn on and off to make a precise image pattern. Therefore, ensure the laser passes over your circuit board faster.

Consequently, you’ll get a shorter printing time and a decent resolution. However, we noticed that circuit board laser printers lack speed. 

PCB Stencil Printer

With stencil printers, you deposit solder paste on your printed wiring boards to create electrical connections. After you’re done with printing, you proceed to component placement. 

The equipment and materials you’ll use here are a printer, stencil, and solder paste. In this case, the solder paste contains metal and solder flux.

Surprisingly, you can use circuit board stencil printers to handle large-volume production. 

PCB Printer Machine

An engineer inspecting a PCB

(An engineer inspecting a PCB)

PCB printer machines eliminate the possibility of interacting with dangerous chemicals and the inconvenience of waiting long before you get your PCB.

Surprisingly, the machines enable you to create prototypes from a workbench by allowing files in Gerber format and letting FR4 out. 

Therefore, the machine will develop insulating ink and traces as a mask between the various layers.

PCB printer machines help you to efficiently and quickly test your ideas. 

FAQ

How much will it cost you to print a flex circuit board?

Most circuit boards will cost you between 50 cents to $500. Surprisingly, a flexible circuit board will cost more than a rigid PCB.

However, additional factors determine the cost of printing a circuit board, including the size and thickness. 

Is it easy to print a flex PCB?

The truth is that printing a flexible circuit board is a complex process that requires some electronic knowledge and experience. However, this is something that you can learn and perfect over time. 

What is the flexible material for PCB?

Most flexible circuit boards use a polyimide film as the substrate. Also, you use adhesives to attach the different layers.

Finally, you can cover and protect your flex circuit board using coverlay

Conclusion

With better technology nowadays, you don’t have to outsource any printed circuit board manufacturing aspect. You can buy a reliable flex printer and do everything from home.

However, flex printers vary in size and price and could go as high as $100,000.

Fortunately, you can get lower specification models for as low as $5,000. For more information on solutions specific to your needs, contact us.