Table of Contents
Why is purple PCB popular?
The world of PCB fabrication is constantly evolving, allowing users to create modernized electronic products that are packed in small enclosures. While these electronic devices are getting smarter and getting an appealing look, developers are trying to make their PCB boards of such electronic devices look more aesthetically appealing. That is where Purple PCB comes into play.
Aesthetics is not the only reason electronics manufacturers are using this colored solder mask. There is a lot more. Come with ELEPCB! Let’s move forward and discuss this solder mask type.
What is Purple PCB?
To give you an overview, solder masks are used on PCB and have a dedicated role such as.
- Solder masks prevent oxidation and mitigate short circuits.
- Solder masks serve as insulators between components that have closed traces.
- Solder masks bind with the substrate and give mechanical strength.
- Solder masks only allow solder paste to get into the right areas.
All colored solder masks have the same features , so what is a Purple PCB?
Well, Purple PCB is a type of board that contains a purple solder mask layer rather than a traditional color such as green, red, black, or white.
What are the Specification Ranges of the Solder Mask Layer of Purple PCBs?
The PCB solder mask has various specifications. For example, the dynamic resolution range is controlled by multiple parameters, including components, traces, the thickness and material of the involved layers, etc. The thickness of the mask layer is between 0.2mil-1.6mil. The solder barrier, which is crucial for the green mask, is set at 4mil. A 5mil solder dam is recommended for solder mask layers of other colors. The diameter of the solder mask hole plug lies between 10-25mil.
Table 1 Details of Solder Mask Specifications
| Solder Mask Specifications | Details |
| Factors Controlling Dynamic Resolution Range | Components, Traces, Thickness and Material of Involved Layers |
| Thickness of Mask Layer | 0.2mil – 1.6mil |
| Solder Barrier for Green Mask | 4mil |
| Recommended Solder Dam for Other Colors | 5mil |
Regarding purple PCB masks, the specification ranges depend on a variety of factors, including the type of PCB manufacturer and the components/materials that are being used. However, here are the general specifications for this colored PCB mask.
- The wet film thickness for this material before curing shall be 20–30 mm, with a dry film thickness after curing of 9–11 mm.
- Talking about color consistency, since this color is not that common, it can be difficult to produce PCBs that have the same color across batches. It all depends on the curing process and manufacturing steps.
- Talking about adhesion, the mask should be able to withstand pressure during the manufacturing process by strongly adhering to the copper face. Adhesion strength should lie between 2B to 3B on the D3359 test.
- For purple PCB, it is important that the tolerance for pads and traces is optimum. To effectively get the right Purple PCB, the tolerance for registration should be around 50 mm.
- In order to effectively qualify for purple PCB, it should be able to withstand scratches and wear-tear. The hardness of purple PCB should be greater than 6H on the scale of the D3363 test.
- Purple solder masks should be able to handle extreme soldering temperatures of up to 290 degrees for more than 20 seconds.
- To prevent short circuits, the Di-electric strength of purple PCB should be 600-1000V/mil.
Additional Parts of Purple PCB Compared to Other PCB Color Types
Compared to traditional colored PCBs, purple PCB has the same amount of parts. But, we can say that purple PCB has more enhancements than additional parts.
Here are the additional enhancements that are done when choosing purple PCB.
- The first part of purple PCBs is that these PCBs are created using specific color agents to keep the same color consistency. Moreover, additional layers of UV protection are also used because purple is more sensitive than other colors such as green or red.
- To improve the color enhancements, purple PCBs are equipped with premium silk screen colors such as silver or golden so that assemblers can easily read the PCB. Moreover, purple PCBs are used for limited-edition projects that contain additional artwork, logos, and custom designs.
- Purple PCBs contain high-end materials such as substrates with high tg, ENIG gold-pated pads, and MCPCBs for improved results.
- Lastly, to ensure that purple PCB meets the required functionality and aesthetic appeal, additional QA tests such as color uniformity tests and improved registration process.
Factors that Make Purple PCB
a Perfect Choice in PCB Manufacturing
There are a lot of reasons why you should use Purple PCB instead of colors such as green or red. Let’s cover the details of why Purple PCB will be a perfect choice for your electronic product.
1.Aesthetics and Brand
Purple is a rare color in the PCB manufacturing process. Since, it is rare, using it in your product will improve the aesthetic appeal, and give a premium look. This will also help in creating brand awareness among your user base.
2. Optimization of EMI/EMC Shielding
Purple color PCBs are perfect for applications that involve radio signals. Due to color absorption, the purple PCB helps in optimizing EMI/EMC shielding, making it suitable for applications that involve IoT and 5G technologies.
3. Improved Thermal Performance
Dark colors PCBs such as purple allow for better thermal performance due to the fact that they are better at absorbing and dissipating heat.
4. Follow Environmental Restrictions
Purple PCBs can withstand greater temperatures such as temperature rise when soldering components. Since these PCBs can handle extreme temperatures, that makes them compatible with lead-free soldering, making them halogen/lead-free.
Major Differences Between Purple PCB and Green PCB
Table 2 Major Differences Between Purple PCB and Green PCB Board
| Purple PCB | Green PCB | |
| Layout |
Purple PCBs are chosen for aesthetics and unique appeal. The contrast of purple PCB is lower and this makes it difficult for troubleshooting. Are used in electronics that are premium. |
Green PCBs are used for bulk production. Green PCBs are common in the industry and have the capability of offering contrast for debugging and component placement. Green color provides a clear view of solder joints, assisting in system design. |
| Assembly |
Purple PCBs require manual processing due to lower visibility. Can lead to higher costs because assemblers have to do additional settings. Are not easily available, leading to delays in projects. |
Green PCB are used in automating manufacturing processes. Perfect for the soldering type that includes reflow and wave. Green PCB faults are easily traceable in the assembly line because the equipment is calibrated for green masks. |
| Recycling |
Purple PCBs are difficult to recycle because of additional dyes and colors. These PCBs have additional layers, which makes it difficult to recover materials like metal and gold. |
Green PCBs are more common, hence their materials are designed to be more environmentally friendly. These materials can reduce the cost of recycling and provide easy ways. |
Purple Electronics
-The Electronic Component Side of Purple PCB vs Others
Electronic components across all PCB colors are the same and have the same functionality. There are slight differences between electronic components that depend on factors such as aesthetics, design parameters, and manufacturing steps. Let’s talk about these differences.
Branding Components
- With other colors, standard industry-common components are used without worrying about the color. The housings and LEDs are also of standard color, such as green, white, and red.
- Purple PCBs are used in areas where it is important to show that the product is distinct and custom-made. So, to match the color of the PCB, components like connectors, terminals, and headers are sourced in purple color. Moreover, purple color LEDs are used to further enhance the appearance.
Optical and Thermal Components
- The color is not related, but PCB colors like black have the capability of causing more heat retention than purple PCBs. This can affect heat-sensitive components.
- Moreover, if there are optical components, purple can help in offering more distinctive as they reflect and have the capability of less light absorption.
Components that are Brand-orientated
- Like in the branding section, ICs and controllers can be purple color and can contain custom-made housings to improve the look of the board.
- Moreover, Purple PCBs are paired with silver and gold layers, compared to green PCBs that have black or blue components.
Cost and Availability of Such Components
- Components that are compatible with standard colors are easily sourceable and have lower costs.
- Sourcing components for Purple PCBs can become expensive due to lower demand and are not easily available.
Conclusion
Purple PCBs are greatly being adopted in industries due to the fact that they look eye-catching. Not only that, these colored PCBs provide heat insulation, EMI/EMC optimization, and environmental advantages compared to other colored PCBs. Also, purple pcb color could do well in pcb board design and allows the board design to distinguish the components or signal paths, which can be used for marking high-speed signal lines, identifying particular components like resistors or capacitors, etc.
To better understand the role and impact of Purple PCBs, come with ELE on this journey and contact our sales team for more information.
FAQs
A2: There are two ways through which purple-colored solder masks are manufactured.
- Using purple pigments and adding them to liquid solder mask material
- Using base color (e.g. white) and then using the printer and purple legend ink to print on the base mask.
A3: A wide variety of industries are adopting purple-colored PCBs.
- Medical industries
- Consumer electronics
- Automobile electronics
- Defense and aerospace industry
CONTACT US
English 
Italian 
Hungarian