FIAT/IFTA World Conference 2015 Vienna

1. Permanent Refreshment of Acetate Media -
A story about passion on innovation.
CREATING
ARCHIVE
INNOVATIONS
Nadja Wallaszkovits,
n.wallaszkovits@noa-archive.com

2. 1936 Wolfgang Sichardt, Switzerland Magnetophon K2
1939 Leandro Mazzoni, Albania Magnetophon K6
1939-40 Armando Leça, Portugal Magnetophon K4 (Ser.Nr. 1260)
1940-43 Alfred Quellmalz, Southern Tyrol Magnetophon K4 (Ser.Nr. 1297)

7. Welcome to the new NOA Research
Department!

9. The vinegar syndrome is a quite complex of interactions:
hydrolytic de-esterification of the cellulose acetate that produces acetic
acid – autocatalytic
chain scission of the cellulose acetate polymer – most dreaded, can lead
to total material breakdown
Both reactions are theoretically reversible hydrolytic processes, but the
reaction to revert would need very high temperature as a trigger
(melting of the material at a melting point of 140°C).
Introduction

10. So therefore, concerning audio-visual materials, the vinegar syndrome
cannot be reverted, but slowed down. Various storage efforts are based
on this knowledge.
A third reaction involved has been monitored already very early in history,
but seems to be an underestimated factor in recent a/v media related
research activities:
loss of plasticiser (and other volatile substances)
relevant for the elasticity and playability of aged a/v media
Introduction

11. Internal Plasticisers
chemically reacted with the polymer
long pendant groups are attached to the polymer chains
(copolymerisation, side chain grafting)
more flexibility of the material can be reached
internal plasticizers are inherently part of the plastic and remain part of
the product – usually not affected by plasticiser loss

12. External Plasticisers
Interact physically, not chemically reacted with the polymer
basically polymer mixtures
most important in commercial applications
Graphics by http://www.greener-industry.org.uk/pages/pvc/1_pvc_AP.htm

13. small size
low molecular weight
= plasticiser molecule
high vapour pressure
high rate of diffusion
high plasticiser efficiency
high volatility
polarity
low hydrogene bonding
= polymer
Graphics:
http://www.naturagart.co.uk

14. big size
high molecular weight
= plasticiser molecule
low vapour pressure
low rate of diffusion
lower plasticiser efficiency
low volatility
polarity
strong hydrogene bonding
= polymer
Graphics:
http://www.naturagart.co.uk

15. Diffusion of plasticiser is depending on
• size of the surface exposed to the atmosphere
• thickness of the diffusion zone
• diffusion coefficient – raises with plasticiser concentration
• saturation concentration & vapour pressure of the plasticiser
• plasticiser concentration & vapour pressure of the atmosphere
• temperature
• atmospheric pressure (vacuum accelerates)
the higher/bigger, the faster

16. Typical example for diffusion of plasticiser
depending on the size of the surface exposed to the atmosphere
Inner parts – tighter pack – less exposed
Outer parts – less tight pack – comparatively big regions exposed to atmosphere

17. Which materials can be affected?
• Basically: all data carriers produced from plastics containing
plasticisers and/or other volatile components
In particular:
cellulose acetate (CA)
cellulose mixed esters
polyvinyl chloride (PVC)
To less extent eventually:
polyethyleneterephthalate (PET)
biaxial oriented polyethyleneterephthalate (boPET, Mylar)
polyethylennaphthalate (PEN)
→ detailed production process often unknown
→ use and characteristics of plasticisers unknown

18. Examples for affected A/V materials
• Instantaneous „wax“ cylinders, as volatile components may be in the
mixture (usually metallic soap with added wax and inorganic
stabilizers)
• Shellac discs: contain camphor, castor oil, ethylphathalate,
triphenylphosphate, tricresylphosphate and other volatile components
and plasticisers
• Photographic/cinematographic film materials on nitrocellulose base
• Photographic/cinematographic film/ magnetic tape materials on
cellulose-acetate base
• Instantaneous discs on PVC base (e.g “Decelith”)

19. substrate magnetic coating
• shrinks to a lower degree
or stays inherently stable
Theoretically: maximal shrinkage of ~ 15-20%!
In practice typically ~ 5-10%
Evaporation of plasticisers
Plasticiser and other volatile
components
• evaporate from the substrate
• result: brittleness, deformation,
shrinking, loss of elasticity,
loss of tensile strength
→ worst case: unplayable

20. magnetic layer
substrate

24. Wypych, George:
Handbook of Plasticizers,
Second Edition, 2012
Chapter 11
Plasticizers Use and Selection
for Specific Polymers
List of polymers
containing plasticiser(s)

25. Problem solving approaches

26. Vinegar syndrome:
• First detected 1948
• First problem solving approach: 1923!
Inventor:
Johann Jacob Friedrich Stock
Munich

27. „Method for the conservation and regeneration of celluloid and objects thereof“
e.g. collar stiffeners…

29. • Phonogrammarchiv in cooperation with the OFI (Austrian Research
Institute for Chemistry and Technology in Vienna) has developed a
method to permanently refresh the elasticity of the material, so that the
playability is given or regained for long time.
• During this chemical treatment it is possible to increase the
concentration of plasticiser in the material. As a quite positive side
effect, the treatment is able to significantly slow down the vinegar
syndrome or – depending on the degradation degree of the individual
tape – even stop it
• Diffusion process in the liquid phase, chemical equilibrium is re-
established or approximated

30. • The reconditioning fluid comprises one or more liquids selected in
such a way that it is substantially inert compared to the data carrier
• This means, that the fluid does not form any chemical bond with the
data carrier, and does not diffuse into or swell the data carrier
• The reconditioning fluid comprises a non-volatile plasticiser or a
mixture thereof
• The concentration of the plasticiser in the reconditioning fluid is
selected such that the gradient of the change in volume of the data
carrier owing to the replacement of plasticiser with the reconditioning
fluid is positive
• With such a fluid, the data carrier can remain in contact with the
conditioning liquid for a long time, the plasticiser being able to
penetrate into the data carrier without problem

31. Decades…

32. Refreshed in 2012, today still the same flexibility

33. before after

36. Aim in the cooperation with NOA:
Provide a substantial preservation treatment that offers the archives
- more time for preservation and prioritisation decisions
- more quality in transfers and
- less resource intensive climate control
Challenge:
From an academic patent to the market:
A hell of a work.

37. Introducing methods to control the process – from destructive chemical
analysis methods to non-destructive verification and quality control
• Optical quality control
• Mechanical quality control
• Chemical verification
• Introduction of environmentally beneficial chemicals, unproblematic in
handling (REACH conform)
…non toxic
…non flammable
…applicable without risk!

38. Optical control setup

41. IT8 Target

44. original
after treatment
before treatment

45. Mechanical control setup

50. Mechanical reference values indicated by
SMPTE:
3N for 16mm
5N for 35mm
minimum: 1N (35mm)
maximum: 7N (16mm and 35mm)

52. Chemical verification

53. Gravimetric verification
of plasticiser diffusion
by laboratory scale

56. Chemical verification of treatment success (quantification) by
Gaschromatographic (GC) analysis:
1 0 . 0 0 1 2 . 0 0 1 4 . 0 0 1 6 . 0 0 1 8 . 0 0 2 0 . 0 0 2 2 . 0 0 2 4 . 0 0 2 6 . 0 0 2 8 . 0 0
0
5 0 0 0 0 0
1 0 0 0 0 0 0
1 5 0 0 0 0 0
2 0 0 0 0 0 0
2 5 0 0 0 0 0
3 0 0 0 0 0 0
3 5 0 0 0 0 0
4 0 0 0 0 0 0
4 5 0 0 0 0 0
5 0 0 0 0 0 0
5 5 0 0 0 0 0
6 0 0 0 0 0 0
6 5 0 0 0 0 0
7 0 0 0 0 0 0
7 5 0 0 0 0 0
8 0 0 0 0 0 0
8 5 0 0 0 0 0
9 0 0 0 0 0 0
9 5 0 0 0 0 0
T im e - - >
A b u n d a n c e
T I C : F O L I E 4 . D d a t a . m s
1 0 . 0 0 1 2 . 0 0 1 4 . 0 0 1 6 . 0 0 1 8 . 0 0 2 0 . 0 0 2 2 . 0 0 2 4 . 0 0 2 6 . 0 0 2 8 . 0 0
0
5 0 0 0 0 0
1 0 0 0 0 0 0
1 5 0 0 0 0 0
2 0 0 0 0 0 0
2 5 0 0 0 0 0
3 0 0 0 0 0 0
3 5 0 0 0 0 0
4 0 0 0 0 0 0
4 5 0 0 0 0 0
5 0 0 0 0 0 0
5 5 0 0 0 0 0
6 0 0 0 0 0 0
6 5 0 0 0 0 0
7 0 0 0 0 0 0
7 5 0 0 0 0 0
8 0 0 0 0 0 0
8 5 0 0 0 0 0
9 0 0 0 0 0 0
9 5 0 0 0 0 0
T im e - - >
A b u n d a n c e
T I C : F O L I E 5 . D d a t a . m s
Before treatment After treatment

57. Based on the destructive GC tests:
Creating a reference curve to verify the treatment success by
means of non destructive methods:
Attenuated Total Reflectance – Fourier Transform Infrared
Spectroscopy (ATR-FTIR)

58. Chemical verification of
de-acidification process

60. Chemical verification of deacidification by refractive methods

61. Many thanks also to the project consultants:
Dr. Peter Liepert
Dr. Lidija Spoljaric-Lukacic
Univ. Prof. Dr. Erich Schmid
Dr. Josef Bailer
Dr. Wolfgang Werther

62. For more information about the refreshment and the resulting
product, please contact
CREATING
ARCHIVE
INNOVATIONS
Jean-Christophe Kummer
c.kummer@noa-archive.com

63. Thank you for your attention!
Nadja Wallaszkovits,
n.wallaszkovits@noa-archive.com
Jean-Christophe Kummer
c.kummer@noa-archive.com