ISO/IEC 8441-1:1991

INTERNATIONAL
STANDARD 84414
First edition
1991-05-15
Information technology - High density digital
recording (HDDR) -
Part 1:
Unrecorded magnetic tape for (HDDR)
applications
Technologies de i’informa tion - Enregistrement numkrique 5 haute
densite (HDDR) -
Partie 1: Bande magnetique vierge pour les applications HDDR
--
---
--
--
= Z
--
-
-z
=
= =
=
z
;
I
- -
L
z
g
= Reference number
E
=
z
Z
z
G?T G
--____I_ ISO/IEC 8441-1:1991(E)
~__-----
ISOAEC 8441=1:1991(E)
Contents
Paqe
.
. . . . . . . . . . . . . . . . . . . . . . . . . . . . .*.
1 Scope .
.................................. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2 Normative references
................................. 1
3 Definitions
... ..............................
4 General . . .
4.1 Materials . .
.....................................................................................
4.2 Tape reels
4.3 Tape wind . .
4.4 Packaging .
rj
5 Test conditions .
5.1 General . .
..................................................................................
5.2 Conditioning
.............................................. ............................
5.3 Test environment
6 Dimensions .
........ 3
6.1 Tape width . .
6.2 Tape length .
..............................................................................
6.3 Tape thickness
.........................................................................
7 Physical properties
7.1 Yield strength . .
7.2 Elongation under stress .
....................................................................................
8 Performance
8.1 Reference test system .
......................................................................................
8.2 Sensitivity
............................ 5
8.3 Wavelength response .
............................................ 6
8.4 Output level uniformity (long term)
....................................
8.5 Instantaneous nonuniformity (dropouts)
0 ISO/lEC 1991
All rights reserved. No part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, Including photocopylng and microfilm, without
permission in writing from the publisher.
lSO/lEC Copyright Office l Case Postale 56 l CH-1211 Genkve 20 l Switzerland
Printed in Switzerland
ii
EC 8441=1:1991(E)
..s.............*........... 6
8.6 Signal-to-noise ratio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
............................................. ............................... 8
8.7 Ease of erasure
....... ................................ ................ 7
8.8 Electrical surface resistance
........................................................ 9
8.9 Environmental performance
8.10 Durability . 9
Abrasivity .
8.11
Annexes
.......... IO
A Glass- and metal-flanged tape reels .
B Wear of recording heads .
C Environmental conditions . . .
Cl General .
......... 12
C.2 Normal operating conditions .
................................................. 12
C.3 Extended operating conditions
.................................................. 12
C.4 Severe operating conditions3)
C.5 Shipping and short-term storage . . 12
............................ 12
C.6 Extended shipping and short-term storage
C.7 Recommended long-term storage .
C.8 Deterioration of tape arising from exposure to adverse
......................................................... 12
environmental conditions
..................... .................................. 14
D Severe operating conditions
D.1 Application .
......... .................................................................... ..... 14
0.2 Conditions
0.3 Environmental performance tests for limited duration recording
under severe conditions . . 14
.............................................. 14
0.3.1 Definition of severe conditions
0.3.2 Requirement .
........................................................................ 14
D,3,3 Test procedure
E Surface electrical resistance testing .
........................................ 16
E.1 Scope .
......................................... .............. 16
E.2 Test specimens .
E.3 Apparatus .
E.3.1 Electrodes for testing insulation resistance .
.
. . .
III
ISO/IEC 8441=1:1991(E)
........ 16
E.3.2 Electrodes for testing volume and surface resistance
E.3.3 Electrode materials .
potential . 16
E.3.4 Direct-current
E.3.5 Measuring equipment . 17
.............................. 17
E.3.6 Switches and keys .
................................... 17
E.4 Procedure .
..................................................... 17
E.4.1 Conditioning of specimens
..................................... 17
E-4.2 Precautions in mounting specimens
resistance . 17
E.4.3 Method of measuring
...................................... 19
E.4.4 Insulation resistance determination
.................... 19
E.4.5 Volume and surface resistance determination
.......................................... 20
E.4.6 Surface resistance determination
................................ 21
E.5 Report .
.................................... 26
F Tape abrasivity testing .
..................... 26
F.1 Scope .
...................................................................................... 26
F.2 Principle
Apparatus .
F.3
Sensor . .
F.3.1
F.3.2 Dummy head assembly . .
F.3.3 Tape abrasivity meters) .
F.3.4 Reference tapes) .
........................... 26
F.4 Procedure .
........................................................ 26
F.4.1 Cleaning and measuring
........................................ 27
F.4.2 Requirement . .
.......................... 28
G Bibliography .
iv
ISO/IEC 8441=1:1991(E)
Foreword
IS0 (the International Organization for Standardization) and IEC (the
International Electrotechnical Commission) form the specialized system
for worldwide standardization. National bodies that are members of IS0
or IEC participate in the development of International Standards through
technical committees established by the respective organization to deal
with particular fields of technical activity. IS0 and IEC technical com-
mittees collaborate in fields of mutual interest. Other international or-
ganizations, governmental and non-governmental, in liaison with IS0
and IEC, also take part in the work.
In the field of information technology, IS0 and IEC have established a
joint technical committee, ISO/IEC JTC 1. Draft International Standards
adopted by the joint technical committee are circulated to national bod-
ies for voting. Publication as an International Standard requires ap-
proval by at least 75 % of the national bodies casting a vote.
International Standard lSO/IEC 8441-1 was prepared by Joint Technical
Committee ISO/IEC JTC 1, Wormafion technology.
ISO/IEC 8441 consists of the following parts, under the general title In-
formation technology - High density digital recording (HDDR):
- Part 1: Unrecorded magnetic tape for (HDDR) applications
c
- Part 2: Guide for interchange practice
Annexes A, B, C, D, E, F and G of this part of ISO/IEC 8441 are for infor-
mation only.
Introduction
This part of ISOAEC 8441 gives guidance on the performance levels of
unrecorded tape suitable for high density digital recording for inter- 5
change purposes. It should be noted that the performance levels speci-
fied may differ from those attained at the time of purchase of the tape.

ISOllEC 8441-1:1991(E)
INTERNATIONAL STANDARD
Information technology - High density digital recording
(HDDR) -
Part 1:
Unrecorded magnetic tape for (HDDR) applications
3 Various tests and procedures herein refer to recording
1 Scope
with a.c. HF bias. In practice, certain HDDR systems do
not use bias. The use of bias in this part of ISO/IEC 8441
does not imply that the tape so tested is in any way un-
suitable for a biasless system.
This part of ISO/IEC 8441 specifies requirements for
unrecorded magnetic tape designed for high density
digital recording (HDDR) having the following
2 Normative references
characteristics:
The following standards contain provisions which,
a) nominal thickness 25,4 urn (0,001 in);
through reference in this text, constitute provisions
of this part of ISO/IEC 8441. At the time of publica-
b) longitudinal magnetic orientation;
tion, the editions indicated were valid. All standards
are subject to revision, and parties to agreements
c) coercivity 72 kA/m (900 Oe) max.
based on this part of ISO/IEC 8441 are encouraged
to investigate the possibility of applying the most
These tapes are suitable for interchange in accord-
recent editions of the standards indicated below.
ance with ISO/IEC 8441-2.
Members of IEC and IS0 maintain registers of cur-
rently valid International Standards.
Requirements for packaging are also included.
IS0 1184:1983, Plastics - Determination of tensile
NOTE 1 Tapes of coercivity above 32 kA/m (400 Oe) are
properties of films.
usually classified as high energy tapes and users should
establish compatibility with equipment used for driving
them.
IS0 1860:1986, Information processing - Precision
reels for magnetic tape used in interchange instru-
Annex A gives guidance on glass and metal-flanged
mentation applications.
reels. Annex B gives information on the wear of re-
cording heads. Different categories of environmental
conditions and their effects on tape are dealt with in
annex C. Severe operating conditions are con- 3 Definitions
sidered in annex D. Surface electrical resistance
testing is dealt with in annex E. A tape abrasivity
For the purpose of this part of ISO/IEC 8441, the fol-
testing technique is described in annex F. A list of
lowing definitions apply.
bibliographical references is given in annex G.
NOTE 4 Tape speed is taken to be 3048 m/s (120 in/s),
NOTES
unless otherwise stated.
2 It is recognized that archival interchange tapes, or
3.1 abrasivity: The propensity of a magnetic tape to
those produced by systems in use prior to the publication
cause wear of a recording head, by the passage of
of this part of ISO/lEC 8441, may not comply with the re-
quirements and/or recommendations herein. the tape over the head.

ISOAEC 844%1:1991 (E)
NOTES duration, in microseconds, for a tape speed of 3048 m/s
(120 in/s) (for a general definition, see ISO/IEC 8441-2).
5 It may be expressed as micrometres of head wear per
metre of tape passed (microinches per inch), or as a value
3.8 operating bias current: That bias current
relative to a given reference tape.
through the recording head which gives a 2 dB fall-
off (overbias peak) of the peak output from the ref-
6 The actual wear produced in the recording head will
erence tape when a 2,0 MHz signal is recorded at
also depend on the tape speed and tension (see
reference level (see 3.13), at a tape speed of
annex B).
3048 m/s (120 in/s).
3.2 durability: The ability of a tape to maintain its
3.9 output level uniformity (long term): The differ-
output uniformity and dropout characteristics after
ence between the maximum and minimum peak
a given number of passes on the reference test re-
output levels, the peak value in either case being the
corder.
value that contains 95 % of the peaks (see figure 1
and 8.4).
3.3 ease of erasure: The ability of a specified eras-
ing field to effect a specified reduction in the level
of a signal recorded on a tape.
95 % probability band Envelope of peak amplitudes
r /
3.4 ele
...