Browse Prior Art Database

Thermal Transfer Color Post Processor

IP.com Disclosure Number: IPCOM000118022D
Original Publication Date: 1996-Aug-01
Included in the Prior Art Database: 2005-Mar-31
Document File: 2 page(s) / 61K

Publishing Venue

IBM

Related People

Lee, HC: AUTHOR [+2]

Abstract

It is desired to add spot color to the output of high speed (100 PPM and higher) electrophotographic printers.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 52% of the total text.

Thermal Transfer Color Post Processor

      It is desired to add spot color to the output of high speed
(100 PPM and higher) electrophotographic printers.

      However, in order to be able to print, the color technology
must be capable of printing at paper speeds of 30 in/sec, print on
paper used in an E.P. printer, be very reliable and have a low total
cost of printing.  In thermal transfer printing paper speeds of up to
approximately 10-15 in/sec can be achieved, typically a smooth paper
surface is required, and the ribbon must run at a speed much lower
than the paper speed in order to achieve a low total cost of
printing.

      A proper paper velocity profile for an entire sheet of paper
must be maintained as it passes under the thermal print head.  The
paper is first reduced in speed from 30 in/sec to 10 in/sec; the
paper is accelerated to a peak of 60 in/sec; kept at this slew speed,
and finally decelerated to 30 in/sec.  In order to maintain steady
state with the prior E.P. process the areas above and below the 30
in/sec must be equal in order to maintain an overall average speed of
30 in/sec.  For a typical high performance stepper motor the time
required for the acceleration and deceleration phases is
approximately 21 ms.  In order to achieve the variable speeds
mentioned above without  tearing paper a small loop of accumulator
section/length of paper must  be maintained.  This accumulator
section is under no tension and is maintained at the same length
prior to each sheet of paper entering the  loop...