Mailing Study

The use of digital color printing for short run or personalized marketing pieces is increasing rapidly. A significant percentage of those pieces end up as self-mailers (no envelope) in the mail stream. Letter-sized postcards are particularly popular because they are less expensive and recipients cannot easily ignore the messages.

As self-mailers pass through the postal stream they are subjected to different machines that are prone to create marks and scuffs on the images. There is the belief by many that coating gives them a protective shield. To help quantify this damage to digitally-produced postcards Printing Industries of America undertook a study.

The test piece for this study was a direct mail full color card containing heavy color coverage on one side and lighter coverage on the back where half of the area was left for the addressing information. The heavy ink coverage on the cards was designed to highlight damage. The front and back of the card are shown to the right. As can be seen the cards were sent as Standard Mail (AADC rates) using the POSTNET™ barcode.

The cards were produced at the Printing Industries of America in Sewickley, PA using a Konica-Minolta bizhub C8000 press with standard toners on 10-point card stock. The study required 2,200 cards printed on two sides. The front sides of half of the cards were coated offline with Techwet UV coating. None of the back sides of the cards were coated.

The printed samples were inspected and divided into eleven groups—each group consisting of 100 coated and 100 uncoated cards. Each set was carefully shrink-wrapped, boxed and sent to participating affiliates who unpackaged the cards and mailed them back to the Printing Industries of America headquarters in Sewickley, PA. The eleven participating mail sources were located in: Amherst, NY, Orlando, FL, Chicago, IL, Portland, OR, St Paul, MN, Los Angeles, CA, Milwaukee, WI, Dallas, TX, Nashville, TN, Phoenix, AZ, and Pittsburgh PA.

Upon arrival at our research center the cards were evaluated for the severity of damage. The cards were sorted into 22 groups according to their points of origin and whether they were coated or uncoated. Initially. All of the cards were delivered from nine of the eleven Post Offices from which the cards were mailed. Of the 200 cards mailed from Florida, four were not delivered, a 2% loss rate. Additionally, one card was lost from the shipment originating in Minnesota, a 0.5% loss rate. This finding was consistent from the previous iterations of this study where a small percentage of the cards were not delivered by the Postal Service.

Of the cards that were received, 50 cards were randomly selected from each group to be subjected to detailed analysis. Examination of multiple examples of the test piece led to the categorization of defect types. The defect categories were determined on the basis of type of damage and its general location. The defect types are listed below. After examining multiple samples, it was clear that a given type of damage to the cards tended to be clustered in specific areas. The data categories, therefore, reflect both a type of damage and its location.

The team recognized that the defect categories were not equally detrimental to the value of the cards as marketing pieces. For example, a tear in the card was considered to be far more detrimental than a dent along the left edge of the card. Therefore, weighting factors were applied to the defect categories so that the total defect scores would be more representative of the loss of value due to the damage sustained in postal transit.

Defects were divided into 11 discrete groups for the front side of the cards. They are presented here together with their weighting factors:

• Scuffs on the red bar (weighting 2)
• Damage to the left Printing Industries of America logo (weighting 2)
• Damage at the left edge of the card (weighting 0.33)
• Damage to the text on the left side of the card (weighting 1)
• Scratches along the bottom portion of the card (weighting 1.5)
• Rips or surface tears that remove fibers from the card (weighting 3)
• Damage to the right edge of the card (weighting 1)
• Damage to the right Printing Industries of America logo (weighting 1)
• Damage to the text on the right side of the card (weighting 1)
• A machine mark denting the left edge of the card (weighting 1)
• Other damage (weighting 1)

Similarly, six categories of defects were identified for the back side.

• Horizontal mark across the card (weighting 2)
• Damage to the left edge of the card (weighting 1)
• Red ink transfer (weighting 1)
• Damage to the right edge (weighting 1)
• Rips or surface tears that remove fibers from the card (weighting 3)
• Other damage (weighting 1)

The results from the analysis showed that the biggest predictor of damage to the postcards was the mailing location. The performance of the mailing centers can be related to the maintenance of the equipment in the facility and the set-up of those devices. The best performance on the front (coated and uncoated) and the back of the card was from the Pittsburgh facility, probably in large part because the short journey required less mail handling and processing.

The magnitude of the differences based on mailing location is more apparent with the uncoated that with the coated samples. Whether a piece was coated or not also correlated to the extent of damage, but to a much smaller extent compared to the mailing location. There was no correlation between the overall damage on the uncoated address side of the card and whether the front was coated or not, though the type of damage did vary. Therefore, the results from the back of the postcard for the coated and uncoated fronts have been combined.

The results for the different locations are listed below from the lowest to the most severe damage. Where multiple locations are listed together there is little statistical difference between the results.

Front coated postcards

• PA
• NY, IL, OR, TX, AZ, FL, MN
• CA
• TN, WI

Front Uncoated Postcards

• PA
• IL
• TX, MN, CA, OR
• NY, FL
• WI
• TN, AZ

Back of the postcard

• PA
• IL
• TX
• MN
• OR, CA
• FL, NY, AZ, TN
• WI

There will be a Research Technology Report and a TAGA paper published on this that will go into significantly more detail on these results. For more information, contact Dr. Mark Bohan at mbohan@printing.org.