How To Perform Paper Curl Correction

Paper Curl Correction:

• Paper Curl Overview
  

• Paper Curl Correction Options
  

• Run Paper Curl Correction
  

Paper Curl Overview

This option allows you to select the appropriate paper curl setting in order to prevent your output from curling. This section provides an overview of paper curl, the causes, and why adjustments may be required in order to obtain optimum print output.

When paper is exposed to heat, the paper loses moisture and curls toward the heat source. High dry ink/toner coverage jobs tend to curl more due to the dryink/toner plastification effect on the paper surface. The system tries to reduce this by using mechanical devices within the paper path called decurlers.

Paper curl is caused by many variables, including:

• The weight of the paper and whether it is coated or uncoated.

• The amount of dry ink/toner and the area being covered on a sheet;the heavier the coverage, the greater the tendency to curl.

• How the paper is loaded in the tray. Make sure you load the paper as instructed on the ream wrapper.

• The atmospheric conditions of the room where the paper is stored, especially those related to humidity and temperature.

• The heat generated during the fusing processes.

Your system is designed with an automated setting to control curl. When using the system Default, the press automatically sends paper through the proper decurler. The system Default automatically determines the amount of pressure needed at the different decurlers in order to reduce the output curl of the paper.

With some print jobs, the output prints still may be curled more than is necessary even after using the system default. In those cases, use the Paper Curl Correction option in the Advanced Stock Setup window to compensate for paper curl in your prints. Paper Curl Correction settings are based on the job type and image density ratio.

Note: It is important to remember that a successful paper curl correction setting used today may not be the same setting that you would use on another day. This is especially relevant if the room in which the press is located experiences changes in temperature and humidity.

The Paper Curl Correction options from the Advanced Stock Setup window include:

• Adjust 1 Sided-Face Up: This option allows you to set specific paper curl information for one-sided only printed output that exit the press in the face-up position.

• Adjust 1 Sided-Face Down: This option allows you to set specific paper curl information for one-sided only printed output that exit the press in the face-down position.

• Adjust 2 Sided - Side 1: This option allows you to set specific paper curl information for two-sided printed output when jams or curling occur along the return paper path after Side 1 prints.

• Adjust 2 Sided - Side 2: This option allows you to set specific paper curl information for two-sided printed output when jams or curling occur along the return paper path after Side 2 prints.

• Correcting the Paper Curl: Use this procedure when selecting or setting paper curl correction options for a stock entry (either a new permanent stock or a modification to an existing stock).

1-Sided-Face Up Option:

Select the Edit Settings button and then the appropriate settings for one-sided only print jobs that will exit the press in the face-up position.

• 1-Sided-Face Up Curl Correction: Select either Default or from the Custom menu, select the setting that best describes the curl issues on your output.

• Front Print Density: Enter the appropriate print (dry ink/toner) density amount; amounts range from zero to seventy percent. If your output is a high dry ink/toner coverage area on the output, you can enter a higher print density amount. The system default value is 10%.

Tip: You may need to run several test prints, evaluate the output, and re-adjust the values before achieving the appropriate output.

Select the Edit Settings button and the appropriate settings for one-sided only print jobs that will exit the press in the face-down position.

• 1-Sided Face Down Curl Correction: Select either Default or from Custom the pull-down menu, select the setting that best describes the curl issues on your output.

• Front Print Density: Enter the required print (dry ink/toner) density amount; amounts range from zero to seventy percent. If your output is a high dry ink/toner coverage area on the output, you can enter a higher print density amount. The system default value is 10%.

Tip: You may need to run several test prints, evaluate the output, and re-adjust the values before achieving the appropriate output.

Select the Edit Settings button and the appropriate settings for two-sided only print jobs.

• 2-Sided Curl Correction: Select either Default or from the Custom pull-down menu, select the setting that best describes the curl issues on your 2-sided output.

• Front Print Density: Enter the appropriate print (dry ink/toner) density amount; amounts range from zero to seventy percent. If your output is a high dry ink/toner coverage area on the output, you can enter a higher print density amount. The system default value is 10%.

• Back Print Density: Enter the appropriate print (dry ink/toner) density amount; amounts range from zero to seventy percent. If your output is a high dry ink/toner coverage area on the output, you can enter a higher print density amount. The system default value is 10%.

Tip: You may need to run several test prints, evaluate the output, and re-adjust the values before achieving the required output.

Use this procedure when selecting or setting paper curl correction options for a stock entry (either a new permanent stock or a modification to an existing stock).

1. From the Advanced Stock Setup window, select the appropriate Paper Curl Correction option from the menu.

   • Severe Upward

   • Medium Upward

   • Moderate Upward

   • Slight Upward

   • No Curl

   • Medium Downward

   • Severe Downward

2. Select the Test Print button.

3. Select the appropriate print density setting.

4. Select the tray where the stock is loaded and the appropriate output quantity to be printed.

5. Select the Print Test button.

6. To close the Advanced Stock Setup window, select OK.

7. To save the changes to the stock and close the Stock Properties window, select OK.

8. To exit the Manage Stock Library, select Close.