ThinkDon is our periodic Question and answer forum with expertise in the world of large format package printing by our VP of Manufacturing, Don Ellis.

ThinkDon - From Huston Patterson Printers

ThinkDon is our periodic Question and answer forum with expertise in the world of large format package printing by our VP of Manufacturing, Don Ellis.

We have been experiencing a lot of cracking when folding our litho laminated boxes. What are some of the possible causes?

There are numerous factors that contribute to excessive cracking of litho laminated boxes. Some of those causes are:
  1. The litho label and corrugation have become too dry causing the fibers to break rather than bend around the fold. The loss of moisture could happen at the time of production or during storage, especially during the dry winter months.
  2. The die may be worn down or not designed properly for the mechanical process being used to die-cut the product. A die maker may be able to suggest a different width, depth or style of score that will facilitate a better fold on a particular piece.
  3. The amount of recycled fiber and the number of times paper stock has been recycled to manufacture corrugation continues to increase. The repeated recycling will continue to shorten the fibers causing them to fracture rather than be long enough to bend around a fold.
  4. The ink film thickness on a score or fold will make cracking more visible. Sometimes, it is possible to either re-design the graphics or change the ink percentages to achieve the same color but with a lower ink film thickness.

I understand that Huston Patterson recently installed a large format digital flatbed UV press. What are its capabilities and how can I utilize it to better serve my clients?

Yes, Huston Patterson has installed a Gandy Pred8tor flatbed UV press. The maximum sheet size of the Pred8tor is 48” x 96” on material up to two inches thick. With a 6 picoliter dot size, the reproduction is very good. Color is managed by GMG software and the Pred8tor is calibrated to G7 standards on a variety of substrates.

We installed the Pred8tor to enhance the services we offer our clients. The digital press can be a lower cost alternative for short run POP displays allowing a manufacturer to test a product in a small number of locations.

Another possible use is to utilize the Pred8tor to reprint small quantities of litho labels or top sheets to fill an order that was short. We offer all substrates we normally print on, as well as a selection of litho labels, SBS and Kalima, pre-mounted to B and E flutes.

Huston Patterson looks forward to meeting your digital print requirements. Please contact your Client Services Manager for samples and further information.

As a G7 Master Printer Certified, what steps were taken to certify your presses?

  1. Linear (no curves applied) plates were made of an approved color test form. The test form includes a G7 press target that contains 275 individual gray of color squares.
  2. Proper ink densities for each color are established on a press that meet the appropriate ISO standards.
  3. Ink and water is balanced across the sheet and 2,000 sheets are run to simulate a normal press run.
  4. Sample sheets are removed from the run.
  5. The G7 press targets are read by the Isis color spectrophotometer.
  6. The spectro readings are then evaluated and curves are established for the individual colors to conform to the G7 standards.
  7. The G7 color test for is then plated with the applicable curves (a curve changes the dot size going to the plate so the printed image meets the G7 standards) applied to each color.
  8. The color test form is put back on press.
  9. Ink and water balance is achieved to the standard ink densities established earlier.
  10. Sample sheets are removed from this run and spectro data is checked to verify it meets the G7 standards.
  11. Sample sheets and the appropriate documentation is sent out for certification approval.

What steps were taken to certify Huston Patterson as a G7 Master Printer and how do you know if your proofs continue to meet G7 standards?

Our pre-press proofing equipment consists of an HPz 6100 color proofer, with in0line spectrophotometer, GM Color Management Software and an Isis Spectrophotometer.

These are the steps taken to become G7 Master Printer certified.
  1. A color test form is proofed. The form contains 1,650 individual color squares.
  2. The color test form is read by the Isis Spectrophotometer.
  3. The readings are sent to the GMG Color Management Software.
  4. The GMG compares the color readings to the G7 standards.
  5. Color adjustments are made to the color profile.
  6. The color test for is then resent to the HPz 6100 with the new color profile.
  7. The color test form is then read by the Isis Spectrophotometer and sent to the GMG.
  8. If the corrected result is within G7 standards the color profile is completed.
To keep producing color proofs that meet G7 standards, our HPx 6100 Color Proofer has an in-line spectrophotometer. Every day a color test is automatically run and read by the spectrophotometer. Any color corrections are automatically made and a new color test strip is ran to verify the proofer is properly calibrated.

A color test strip is added to every proof. The color test strip is automatically read by the in-line spectrophotometer to ensure the color remains with-in a 2.5 delta E. A sticker indicating the color proof meets the G7 standard is attached to the proof.

I know Huston Patterson is G7 Master Printer certified, but what does it mean?

To a print buyer it means:
  1. Huston Patterson has submitted yearly documentation, with supporting proof and print samples, to Ideal Alliance for certification.
  2. The proof received from Huston Patterson will be indicative of the file and each proof is checked with a spectrophotometer to very the color accuracy of the proof.
  3. The printed piece will match the color proof (within the mechanical capabilities of the press).
  4. Each step is repeatable and measurable.
  5. Proofs and printed pieces from various sources that are also G7 Master Printer certified will match, within the limitations of the particular printing method being used.

In our next "Think Don" article, we will present an overview of the process required to become G8 Master Printer certified.

What types of coating does HP offer and what are their characteristics?

Aqueous Coatings
  1. High-Rub Gloss Aqueous Coating – Our everyday gloss coating offers good gloss and consistently 800 rubs on a Southerland Rub Tester. Clients who also test their sheets have reported successful tests at 1,600 rubs.
  2. High Temperature Coating – Targeted for higher than normal temperature environments that may result in normal coating blocking, or sticking together.
  3. Non-Skid Coating – As the name implies the slide angle (the angle at which the label will slide) is greater than the standard coating. Due to the characteristics of the coating, rubs are reduced as the slide angle increases.
  4. Satin/Matte Coating – Used on projects where less gloss is needed. Rubs remain good but, due to the lack of gloss, the coating becomes burnished or marred easier than the conventional gloss coating.
  5. Strike-Thru Aqueous Coating – Used on projects to enhance some area(s) of the graphics. The process results in a slight difference between the gloss & matte areas.
 
UV Coatings
  1. Gloss UV Coating – Excellent gloss, excellent rubs. Applied in-line on most jobs.
  2. Strike-Thru UV Coating – Used on projects to enhance some area(s) of the graphics. The process results in good definition between the gloss and matte areas while continuing to provide very good rubs resistance.

Specialty UV Coatingsavailable thru our partners
  1. Matte UV Coating – Applied off-line.
  2. Raised UV Coating – Applied off-line. Gives a raised feel to specific spot areas.
  3. Textured UV Coating – Applied off line. Gives a raised and textured feel to specific spot areas.

What's grain direction got to do with it?

Grain direction has very important implications for your print job. If it is incorrect, the various components of the corrugated package or display may be incompatible.


There is a wide variety of material manufactured with wood pulp, including sheets for litho lamination, top sheets and corrugation.

The most important rule concerning grain direction, and arguably the only consideration, is for all of the pieces (litho label or top sheet and corrugation) to have the same grain direction. When moisture (adhesive) is applied, the fibers in the stock and corrugation will expand. The fibers must expand in the same direction.

Think of a fiber as a piece of string. If moisture is applied to the string it will swell and become bigger around before the length of the string will change. Therefore, if the grains are not running the same direction, the different pieces will expand and contract in different directions. It is this difference that may cause tunneling, bubbling and excessive curl.

To check the grain direction of a printed or unprinted c1s litho label or top sheet, cut a small section from the corner of the sheet, paying close attention to the orientation of the sample to the sheet. Then, wet the back or uncoated side of the sample. The sample will curl indicating the long direction of the sheet. This is an excellent example of the fibers swelling more around the fiber than the length. The grain direction of corrugation is established by checking the orientation of the flutes. The grain direction is always 90 degrees to the flutes.

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