Problem with 60# High Bulk Dye Sublimation

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Problem

Company is encountering intermittent dirt or "trash" in both the printing areas and non printing areas. Most of the problem occurs on the first printing unit with less material showing up on the 2nd unit and so on down the line.

They are running 4 color process on a 4 color Heidelberg Speedmaster sheet fed press.

Discussion

Our discussion indicated that the dirt problem was less than they have seen on earlier batches of paper but is still enough to cause them considerable problems. We went out to the pressroom where I talked at length to the pressman. He confirmed that the problem was worse on the first print unit and showed up less on the 2nd unit and so on. The dirt would show up in both printing and non printing areas and agreed that this was not consistent with the "normal" hickies a pressman would expect to see. Usually a hickie will adhere to the printing areas because of ink tack. In the non printing areas the hickie has nothing to stick to.

The Heidelberg 4 color Speedmaster was running a live job and some of the dirt problem was able to be observed as it was happening. Indeed, the material attached itself to the blanket and then after a while attached itself to the plate. The fact that the dirt was not limited to sticking to the print areas indicates that it must be embedding itself into the relatively soft surface of the aluminum printing plate and not dependant on ink tack to hold it in place as would the usual ink or fiber hickie. The material seems to be a hard crystal like substance that is picked up from the surface of the sheet. There is no way to be sure if this material came as a result of the sheeting process or not.

The tape pulls I saw looked like ink hickies. This was proven not to be the case as the material was seen migrating up from the blanket to the plate rather than down from the ink train. The material also cannot be paper fiber since it is taking on and transferring ink similar to an ink hickie. A paper fiber would take on water and not transfer any ink. Both ink and paper fiber hickies would always be found in the printing areas and not the non- printing areas because both are smooth or soft and need ink tack to hold them in place. In this case we see small hard particles with tiny sharp points allowing them to embed themselves into the printing plate surface at any point they make contact. Being hard material, they take on and transfer ink, printing an image on the finished print job.

Dye Sublimation Printing Process

• Ink - Conventional Kohl Madden print varnish used as a vehicle with dye sub pigment mixed in house. The specific print varnish was chosen for its solvent flash off rate which is critical in the sublimation process. The resulting ink is almost identical to conventional offset printing ink with the only real difference being that the grind of the solids are slightly coarser. Average ink tack is 16.
• Fountain Solution - Rycoline fountain concentrate. Same fountain solution used in conventional offset printing. pH of 4.0.
• Plates - Conventional Fuji CTP post baked aluminum printing plates. Press runs the same as with conventional offset printing. Ink can be interchanged with no fountain solution or plate process changes.

Next Step

Five skids of Boise paper aerated to clean any loose material from the sheets and sent to Holt for testing.

Past Problem

Company was encountering intermittent dirt or "trash" in both the printing areas and non printing areas. Most of the problem occurs on the first printing unit with less material showing up on the 2nd unit and so on down the line.

Dye Sublimation Printing Process

Problem

Company is encountering intermittent dirt or "trash" in both the printing areas and non printing areas. Most of the problem occurs on the first printing unit with less material showing up on the 2nd unit and so on down the line.

They are running 4 color process on a 4 color Heidelberg Speedmaster sheet fed press.

Discussion

Our discussion indicated that the dirt problem was less than they have seen on earlier batches of paper but is still enough to cause them considerable problems. We went out to the pressroom where I talked at length to the pressman. He confirmed that the problem was worse on the first print unit and showed up less on the 2nd unit and so on. The dirt would show up in both printing and non printing areas and agreed that this was not consistent with the "normal" hickies a pressman would expect to see. Usually a hickie will adhere to the printing areas because of ink tack. In the non printing areas the hickie has nothing to stick to.

The Heidelberg 4 color Speedmaster was running a live job and some of the dirt problem was able to be observed as it was happening. Indeed, the material attached itself to the blanket and then after a while attached itself to the plate. The fact that the dirt was not limited to sticking to the print areas indicates that it must be embedding itself into the relatively soft surface of the aluminum printing plate and not dependant on ink tack to hold it in place as would the usual ink or fiber hickie. The material seems to be a hard crystal like substance that is picked up from the surface of the sheet. There is no way to be sure if this material came as a result of the sheeting process or not.

The tape pulls I saw looked like ink hickies. This was proven not to be the case as the material was seen migrating up from the blanket to the plate rather than down from the ink train. The material also cannot be paper fiber since it is taking on and transferring ink similar to an ink hickie. A paper fiber would take on water and not transfer any ink. Both ink and paper fiber hickies would always be found in the printing areas and not the non- printing areas because both are smooth or soft and need ink tack to hold them in place. In this case we see small hard particles with tiny sharp points allowing them to embed themselves into the printing plate surface at any point they make contact. Being hard material, they take on and transfer ink, printing an image on the finished print job.

Dye Sublimation Printing Process

• Ink - Conventional Kohl Madden print varnish used as a vehicle with dye sub pigment mixed in house. The specific print varnish was chosen for its solvent flash off rate which is critical in the sublimation process. The resulting ink is almost identical to conventional offset printing ink with the only real difference being that the grind of the solids are slightly coarser. Average ink tack is 16.
• Fountain Solution - Rycoline fountain concentrate. Same fountain solution used in conventional offset printing. pH of 4.0.
• Plates - Conventional Fuji CTP post baked aluminum printing plates. Press runs the same as with conventional offset printing. Ink can be interchanged with no fountain solution or plate process changes.

Next Step

Five skids of Boise paper aerated to clean any loose material from the sheets and sent to Holt for testing.

Past Problem

Company was encountering intermittent dirt or "trash" in both the printing areas and non printing areas. Most of the problem occurs on the first printing unit with less material showing up on the 2nd unit and so on down the line.

Dye Sublimation Printing Process

• Ink - Conventional Kohl Madden print varnish used as a vehicle with dye sub pigment mixed in house. The specific print varnish was chosen for its solvent flash off rate which is critical in the sublimation process. The resulting ink is almost identical to conventional offset printing ink with the only real difference being that the grind of the solids are slightly coarser. Average ink tack is 16.
• Fountain Solution - Rycoline fountain concentrate. Same fountain solution used in conventional offset printing. pH of 4.0.
• Plates - Conventional Fuji CTP post baked aluminum printing plates. Press runs the same as with conventional offset printing. Ink can be interchanged with no fountain solution or plate process changes.

Discussion

Aeration of sheeted 60# Dye Sublimation High Bulk paper was successful in eliminating the debris that was causing all of their problems on press. This is seen as only a temporary solution and allows them to run existing inventory. A permanent solution was trialed in two new coating formulations with an emphasis on making the coating more flexible and not prone to fracturing and flaking off during the sheeting process.

Trial Run

ME-23 - 28 x 40 60# Dye Sublimation High Bulk

Mill no. 68263-001

Skid no. OH0110A

The press was loaded with 1500 sheets of the ME-23 condition paper during a live press run consisting of 4 PMS special colors. Blankets were washed and the press run at a speed of 8,000 IPH (their normal run speed) with no feed, registration, print or delivery problems. After the 1500 sheets were run, all 4 of the unit's blankets and plates were inspected for debris. All plates and blankets were clean and free of any of the crystallized debris experienced in previous batches of 60# Dye Sublimation paper. Only a slight amount of edge dusting was seen on the first print unit blanket which is well within normal expectations for offset paper.

ME-24 - 28 x 40 60# Dye Sublimation High Bulk

Mill no. 68263-002

Skid no. OH011A

After running condition ME-23, all blankets were washed and 1500 sheets of condition ME-24 were loaded into the press. The press run was consistent and identical to the ME-23 condition paper. Inspection of all 4 print unit blankets and plates was also consistent and identical with the ME-23 condition paper.

Consultant Conclusion

The new coating formulation on both conditions is seen as a successful solution to the debris problem that Holt had been experiencing for quite some time. The press crew was confident that Boise had solved the past problem of loose crystallized debris embedding into the print plates. They will continue to run the balance of the ME-23 and ME-24 condition paper to re-confirm that the problem is gone.

Ink - Conventional Kohl Madden print varnish used as a vehicle with dye sub pigment mixed in house. The specific print varnish was chosen for its solvent flash off rate which is critical in the sublimation process. The resulting ink is almost identical to conventional offset printing ink with the only real difference being that the grind of the solids are slightly coarser. Average ink tack is 16.

• Fountain Solution - Rycoline fountain concentrate. Same fountain solution used in conventional offset printing. pH of 4.0.
• Plates - Conventional Fuji CTP post baked aluminum printing plates. Press runs the same as with conventional offset printing. Ink can be interchanged with no fountain solution or plate process changes

Discussion

Aeration of sheeted 60# Dye Sublimation High Bulk paper was successful in eliminating the debris that was causing all of their problems on press. This is seen as only a temporary solution and allows them to run existing inventory. A permanent solution was trialed in two new coating formulations with an emphasis on making the coating more flexible and not prone to fracturing and flaking off during the sheeting process.

Trial Run

ME-23 - 28 x 40 60# Dye Sublimation High Bulk

Mill no. 68263-001

Skid no. OH0110A

The press was loaded with 1500 sheets of the ME-23 condition paper during a live press run consisting of 4 PMS special colors. Blankets were washed and the press run at a speed of 8,000 IPH (their normal run speed) with no feed, registration, print or delivery problems. After the 1500 sheets were run, all 4 of the unit's blankets and plates were inspected for debris. All plates and blankets were clean and free of any of the crystallized debris experienced in previous batches of 60# Dye Sublimation paper. Only a slight amount of edge dusting was seen on the first print unit blanket which is well within normal expectations for offset paper.

ME-24 - 28 x 40 60# Dye Sublimation High Bulk

Mill no. 68263-002

Skid no. OH011A

After running condition ME-23, all blankets were washed and 1500 sheets of condition ME-24 were loaded into the press. The press run was consistent and identical to the ME-23 condition paper. Inspection of all 4 print unit blankets and plates was also consistent and identical with the ME-23 condition paper.

Consultant Conclusion

The new coating formulation on both conditions is seen as a successful solution to the debris problem that Holt had been experiencing for quite some time. The press crew was confident that Boise had solved the past problem of loose crystallized debris embedding into the print plates. They will continue to run the balance of the ME-23 and ME-24 condition paper to re-confirm that the problem is gone.

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