Kelly Paper



Digital Media Education Video - Workbook

Objectives:

← To learn about digital printing

← What papers are appropriate for digital printing

← Learn to be more effective when selling digital media

What is the difference between digital paper and regular offset paper? Isn’t all paper the same?

Just as there is a big difference between a film camera and a digital camera; there is a big difference in the traditional analog printing process and the digital printing process.

The film camera takes great pictures, but there are many more steps involved in getting the captured image onto a piece of photo paper than a digital a digital camera. The digital process allows for faster processing of printed images. It is also a more cost effective method of reproduction.

The Digital Printing Process

There are typically 7 steps that occur in digital laser and color copy printing:

1. RIP – Raster Image Processing

← A digital file is sent to the digital printer as a file. The RIP creates a bit map image of the file which the raster memory renders, and sends it to the paper as a stream of dots.

2. Charging – A primary charge roller projects an electrostatic charge onto a revolving photo receptor, (a photo sensitive drum or belt).

3. Writing – The laser sweeps across the photo receptor while the stream of rasterized data tells the laser to turn on and off to form the dots. This produces an electrostatic negative which determines how the photo receptor picks up the toner.

4. Developing – The latent image picks up the toner, which is particles of dry plastic powder, and applies it to the photo receptor where the laser wrote the latent image.

5. Transfer – The photo receptor is then rolled (or pressed if a belt is used), over the paper, transferring the image.

6. Fusing – The paper passes through rollers and the fuser where heat and pressure bond the melted toner to the paper.

7. Cleaning – Once the printing job is completed a soft blade wipes away any excess toner from the photo receptor.

Why Is Digital Paper Needed?

The Basics of Digital Media

1. Toner Adhesion – Toner produces the printed image by bonding to the paper during the digital printing process

2. Calendaring – The paper surface is calendared through high pressured rollers to create a uniformly smooth surface.

3. The Digital Image Surface Must Be Prepared

← Digital Media = Uniform Smoothness

← Offset Media = Peaks and Valleys

The elimination of peaks and valleys accomplishes three things in the digital printing process:

1. Less toner is required to produce the printed image resulting in reduced cost.

2. Using the appropriate media substrate results in greater equipment life-span, again saving long-term cost.

3. Chemical treatment produces more efficient tonner adhesion.

Moisture content is an important factor in the digital printing process.

The moisture content of digital media is 4% to 4.5%

Low moisture allows digital paper to withstand the high temperature of digital printing equipment.

The moisture content of offset paper is 5% to 5.5%. This higher moisture causes offset media to curl, wrinkle and jam in digital equipment. The results of using the wrong paper in the digital process are lost time and material, and possible damage to the equipment.

Packaging

The packaging of digital paper is different than the packaging of other printing paper products. The purpose of this is to maintain the moisture content of the digital media until the product is sold.

Paper that is not sealed and packaged properly will jam and cause delays in production. It will also result in more service calls and down time.

Precision Cutting

Digital media is cut precisely to the requirements of digital equipment. Precision cutting refers also to the lint free qualities of the paper.

When paper is cut, fibers and lint fall from the paper and will cause problems if not removed. Digital media is cut in a vacuumed environment eliminating lint and fiber residue. This residue would otherwise causes build up on the photo receptor and cause image inconsistency on print jobs.

Grain Direction

Due to the path that the paper travels through the digital equipment, a short grain sheet is needed. Long grain paper will fight against the path of the turns and loops of the printing path.

Another reason the grain direction is important is that digital toner will crack when scored against the grain.

GSM – Grams per Square Meter

GSM is the term meaning the physical weight of digital media. Most digital equipment is manufactured outside of the United States and therefore digital paper is measured using the metric system. Most digital papers include both the U.S. Standard Unit of Measure and the GSM measurement.

General Rule of Thumb

GSM under 220 – Load in the equipment paper tray

GSM over 220 – Must go through the stack bypass. This bypass method allows heavier media to pass through the machine without going through the all of the loops in the path.

To learn more about specific brands of paper that we carry that are suitable for digital printing applications, review the Kelly Paper Digital Medial Guide.

Digital Media Education Video – Quiz

Return to Kelly Paper Online Training to take the quiz online.

Based on this module, circle the correct answer.

1. There are more steps in the traditional analog printing process than in the digital printing process:

a. True

b. False

2. Digital printing is a more cost effective method of reproduction:

a. True

b. False

3. RIP stands for:

a. Radio Inscription Printing

b. Raster Image Processing

c. Rest In Peace

4. How many steps were covered in the digital printing process:

a. 5

b. 8

c. 7

d. 10

5. What are the basics of digital printing:

Chose all that apply:

a. Toner Adhesion

b. Ink absorption

c. Calendaring

d. The Digital Image Surface Must Be Prepared

6. Moisture content is not an important factor in the digital printing process.

a. True

b. False

7. Paper that is not sealed and packaged properly

a. will jam and cause delays in production

b. Is no big deal

c. Is the standard in the U.S.

8. Digital media is cut in a vacuumed environment eliminating lint and fiber residue:

a. True

b. False

9. Due to the path that the paper travels through the digital equipment, a short grain sheet is needed

a. True

b. False

10. GSM stand for, gross size and mass

a. True

b. False

................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download