USPS Smudging Issue on Postcards: Understanding & Preventing Scuffing & Smudging on USPS Mailed Postcards

Mailing postcards is a cost-effective and impactful way to reach out to customers, friends, or family. However, many people encounter an issue where their beautifully designed postcards arrive with smudges, scuff marks, or even slight burn marks. Understanding why this happens and how to prevent it can help ensure your postcards make the best impression upon arrival.

Smudged Barcodes on Postcard. Source: Manhattan Digital Direct

Smudged USPS Postcards. Image Source: PrintPlanet.com

The primary culprit behind smudged or scuffed postcards is the high-speed mail processing equipment used by the United States Postal Service (USPS). Here’s a breakdown of the factors contributing to this issue:

1. High-Speed Sorting Machines

• Friction and Heat: USPS sorting machines process thousands of mail pieces per hour. As postcards travel through these machines, they experience significant friction, which generates heat. This can cause inks, especially those not fully cured or those printed on certain finishes, to smudge or scuff.
• Mechanical Components: Belts, rollers, and other mechanical parts can come into direct contact with the postcard surfaces. This contact can lead to physical scuffing or transfer of ink.

2. Mail Handling and Transportation

• Stacking and Shuffling: Postcards are often stacked tightly with other mail pieces. Movement during transportation can cause abrasion between postcards and other mail, leading to smudges or scuffs.
• Environmental Factors: Exposure to moisture or varying temperatures during transit can affect the ink and paper quality, making them more susceptible to smudging.

3. Ink and Coating Types

• Uncoated or Matte Finishes: Postcards without protective coatings are more prone to damage. The absence of a protective layer means the ink is directly exposed to external elements.
• Heavy Ink Coverage: Designs with large areas of dark or saturated colors are more likely to show smudges or scuffs because any marks contrast more sharply against dark backgrounds.

Here is a video from Quantum Postcards that explains the smudging and scuffing issues on postcards mailed by USPS:

Not Deliverable Mail: Return to Sender. Image Source: Smarty.com

When first-class mail pieces are undeliverable—indicated by a yellow “nixie” sticker from the carrier explaining why they couldn’t be delivered and have been returned—they become especially susceptible to scuffing and marking. This increased vulnerability arises because the USPS takes extra steps to attempt delivery for this class of mail. To confirm that these items are indeed “undeliverable,” the postal pieces are intentionally sent through the Delivery Bar Code Sorters (DBCS) multiple additional times.

The next time your undeliverable first-class postcards are returned to you, take note of how scuffed they may appear. This is due to their repeated passage through the sorting machines, which increases the chances of them getting caught or snagged.

Smudged Postcard. Image Source: Reddit.com

At the top of the sorting bins, a black belt generates enough friction to rub and smear the toner off the paper.

(Top of the sorting bin and black belt)

In the photo to the right, we demonstrate how increasing the pressure of the postcard against the black belt consistently reproduces the smearing effect—every single time!

Preventing smudges and scuffs involves careful consideration of materials and design choices. Here are some effective strategies:

1. Use Protective Coatings

• UV Coating:
  • What It Is: A glossy, liquid-based coating cured under ultraviolet light.
  • Benefits: Provides a hard, protective layer that resists smudging, scuffing, and scratching.
  • Considerations: Not suitable for postcards that need to be written on unless applied only on one side.
• Aqueous Coating:
  • What It Is: A water-based coating that offers a subtle sheen.
  • Benefits: Enhances durability and is environmentally friendly.
  • Considerations: Less glossy than UV coating but still effective in protection.
• Lamination:
  • What It Is: A thin plastic film applied to the postcard surface.
  • Benefits: Offers the highest level of protection against physical damage.
  • Considerations: Increases cost and may affect recyclability.

2. Choose the Right Paper Stock

• Heavier Stock: Thicker paper stocks are more durable and less likely to bend or crease, reducing the risk of scuffing.
• Coated Paper: Glossy or semi-gloss paper stocks have inherent protective qualities compared to uncoated papers.

3. Optimize Design Elements

• Avoid Heavy Ink Coverage: Use lighter backgrounds or incorporate white space to minimize visible smudging.
• Ink Selection: Use inks that are less prone to smudging, such as soy-based or quick-drying inks.

4. Consult with Printing Professionals

• Expert Advice: Professional printers can recommend the best combinations of paper, ink, and coatings based on mailing needs. Our team at PostGrid can help you with the right recommendation and combinations
• Quality Assurance: Reputable printing services often have experience dealing with USPS requirements and can tailor solutions accordingly.

5. Consider Envelopes or Protective Sleeves

• Envelopes: Mailing postcards in envelopes eliminates exposure during transit but may increase mailing costs.
• Protective Sleeves: Clear plastic sleeves can protect the postcard while still displaying the design, though this may not be practical for large mailings.

Understanding USPS Automation Guidelines

Complying with USPS automation guidelines can also reduce the risk of damage:

• Dimensions and Thickness: Ensure postcards meet the standard sizes and thickness to avoid jams or misfeeds in sorting machines.
• Address Placement: Proper placement prevents critical information from being obscured by smudges or scuffs.

While smudging and scuffing of postcards during USPS processing is a common issue due to the nature of high-speed mail handling, it can be mitigated through strategic choices in materials and design. By utilizing protective coatings, selecting appropriate paper stocks, optimizing design elements, and consulting with professional printers, you can significantly enhance the durability of your postcards. Taking these steps ensures that your message arrives in pristine condition, making the intended impact on your audience.