Printing basics

Introduction

Printing basics

This is the usual pattern for a P640i Printer ribbon. Y, M and C are the three “dye sub” process colors. The K panel is for infrared- readable bar codes and other data, usually on the back of the card. A second K panel (YMCKK) is sometimes provided to allow black resin printing on both sides of the card.

As the ID card is driven through the print

Print

head

station, the color ribbon is metered out from

 

the supply roll at the same speed. Each color

 

reqires a separate “pass” of the card. The black

 

dots at the bottom edge of the print head depict

 

the heating elements - in practice, at 300 to the

 

inch, they are too small to be seen with the

Card

 

naked eye.

 

Color migrates from the dye ribbon onto the ID card, the spread of the dye depending on the amount of heat applied by the print head element. Each time it comes to a dye panel boundary, the print head lifts to allow the card to back up, then lowers again to print the next

color.Card

The K (black) panel is a resin that “mass transfers” onto the surface of the card, instead of migrating into it. With mass transfer the printer has little control over a pixel’s size or density - it’s either there or it isn’t. K printing is used for bar codes because it is machine

readable, whereas YMC dyes are not.

Card

 

What makes the P640i a different kind of printer

C

Cyan

Dye M

Magen-

ta Dye

Print head

Print head

Y

Yellow

Dye

K

Black

Resin

Color ribbon

The print station in the P640i has no pinch rollers that need cleaning to maintain accuracy

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P640i Card Printer User Guide

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