An Investigation of the effect of an infrared post-exposure latent image in a 3M dry silver film

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An Investigation of the effect of an infrared

post-exposure latent image in a 3M dry silver film

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AN INVESTIGATION OF THE EFFECT

OF AN INFRARED POST-EXPOSURE ON THE

LATENT IMAGE IN A 3M DRY SILVER™ FILM

by

Thomas J. Cardinali

A thesis submitted in partial fulfillment of the requirements for the degree of Bachelor of Science in the School of Photographic Arts and Sciences in the College of Graphic Arts and Photography of the Rochester Institute of Technology

August, 1982

Thomas J. Cardinali

Signature of the Author. -_ .

Photographic Science and Instrumentation David A. Morgan

Certified by , .

Thesis Advisor Ronald Francis

Accepted by -- .

ROCHESTER INSTITUTE OF TECHNOLOGY

COLLEGE OF GRAPHIC ARTS AND PHOTOGRAPHY

PERMISSION FORM

Title of Thesis AN INVESTIGATION OF THE EFFECT OF AN INFRARED

POST-SXPOSURE ON THE LATENT IMAGE IN A 3M DRY SILVER™ FILM

I Thomas Cardinali prefer to be contacted

each time a request for reproduction of this thesis is made

and to consider each request individually. I can be reached

at the following address.

International Business Machines, Corp.

River Road, Essex Junction, Vermont, 05452

AN INVESTIGATION OF THE EFFECT

OF AN INFRARED POST-EXPOSURE ON THE

LATENT IMAGE IN A 3M DRY SILVERTM _FILM

by

Thomas J. Cardinali

Submitted to the

Photographic Science and Instrumentation Division in partial fulfillment of the requirements

for the Bachelor of Science degree at the Rochester Institute of _Technology

ABSTRACT

An investigation to determine the effect of an

infrared post-exposure on the latent image in blue sensitive

3M _Dry Silver film 7842 was performed. The film was first

given a _step tablet exposure _using the unfiltered output of

a tungsten source at 2856 K. A Wratten #87C filter was used

with the same source to provide the _second, infrared exposure

over one half of the first exposure area. Absolute exposure

and exposure reciprocity were tested. _Processing was _by

immersion into a bath of 3M fluorocarbon FC-43 maintained at

127C/260F.

The original _objective, to cause Herschel effect

bleaching of latent image, was not achieved. All IR exposures

density change. A quanta ratio of 3*106 between the infrared

and actinic exposures was obtained _using an IR exposure time

of 96 hours. The lack of _{any density} decrease due to the

Herschel effect _apparently gives evidence to the _theory that

the Herschel effect is a rehalogenation process as reported

by Farnell and Birch. The presence of halogen acceptors in

the emulsion is believed to prevent the loss of latent image

silver atoms due to rehalogenation. _Further, the emulsion

carrier and _developing agents are IR absorbers and reduce the

ACKNOWLEDGMENTS

I wish to express _my thanks to David Morgan and his

staff at 3M for their _hospitality and assistance with this

project _{during my trip} to St. Paul on 3/16/82. I would like

to _especially thank Doyle _Strong, Roger Shaw and Bob Hawksford

for their _help in _obtaining the _processing fluid and films

required for this project. I would also like to thank _Greg

McCarney for _showing me 3M's _Dry Silver research laboratories

and for suggestions in _establishing and _maintaining process

control with both heated roller and fluid bath _processing

schemes.

I would also like to thank Bill Dahlen and Erich

Florentine of Sperry-Univac _{for allowing} me to spend a _day

consulting with _my advisor _{during my} plant interview in

St. Paul.

I would like to thank the Central Intelligence

Agency for their financial assistance in this project.

TABLE OF CONTENTS

Page

LIST OF TABLES iv

LIST OF FIGURES v

INTRODUCTION 1

I The Herschel Effect 1

II 3M _Dry Silver 4

III Aim of Research 7

EXPERIMENTAL 9

DISCUSSION OF EXPERIMENTAL 12

SUMMARY & CONCLUSIONS 19

LIST OF REFERENCES 22

APPENDIX A 27

APPENDIX B 30

VITA 35

LIST OF TABLES

Page

Table 1. 3M _Dry Silver Films 28

Table 2. _Comparisons of _{Quantum Exposures 29}

LIST OF FIGURES

Page

Figure 1. _Dry Silver Development 5a

Figure la. _Dry Silver _Developing Agents 5a

Figure 2. RLF Sensitometer 10

Figure 3. Refrigeration Test 16

Figure 4. Oven Test 17

Figure 5. _Reciprocity Curve 7842 31

Figure 6. Spectral Sensitivities 32

Figure 7. Spectral Output 33

Figure 8. _{Heat-Developing Dry} Silver 34

INTRODUCTION

I The Herschel Effect

The Herschel effect _generally refers to the

reduction of _density of an exposed silver halide emulsion _by

the destruction of surface-latent image _by a post-exposure to

red or infrared radiation. This was discovered in 1840 _by

Sir John Herschel as he projected a spectrum onto silver

chloride paper which was _{simutaneously} exposed to diffuse

daylight. He observed the printout of photolytic silver in

2

all areas except where the spectrum was "full and _firey red."

Herschel effect is now used to describe the destruction of

3

latent-image silver clusters rather than printout silver.

Two different theories were found to best describe

published experiments. The first involves a redistribution of

4

developable latent images to an undevelopable site. This is

best illustrated _by a special case of the Herschel effect

mechanism, called the Debot effect. This can be shown _by

silver halide crystals which have been given an actinic

exposure to produce both surface and internal latent images.

After exposure the film is treated with a chromic acid solution

and washed. This acid treatment will bleach any surface latent

images, leaving only internal sites. If the film is now

will result. If the acid treated film is exposed to red

radiation _{before processing an increase in density} will be observed as compared to areas which received no red exposure.

This is explained as a redistribution of latent image silver

atoms from undevelopable internal sites to surface sites

where _they can be developed. This redistribution is caused

by the red radiation.

The mechanism is as follows. Upon exposure to

actinic _radiation, the absorbtion spectrum of the film shifts c.

toward longer wavelengths as more and more silver metal

latent-images are formed. Their absorbtion spectrum lies further toward the red end of the spectrum than the silver

halide alone. If a photon is absorbed _by a latent _image,

a silver atom will be lost. Given sufficient _exposure, that

latent image will be destroyed. Though absorbtion of _any

photon _by the latent image will cause the loss of a silver

atom, red and infrared photons are unique in that _they will not contribute to the formation of a latent image should it

strike the crystal _instead; unless of course the crystal was

deliberately sensitized to those wavelengths. This _theory

maintains that the atoms _comprising an exposed latent image

will be involved in the reformation of a latent image at another

location in the crystal. If the crystal has no surface latent

images due to a chromic acid _treatment, upon red exposure some

internal latent images should be redistributed to the _surface,

developer.

This same mechanism operates to cause the Herschel

effect. _{Because the surface region of the crystal is a small}

fraction of the total crystal _volume, when an _exposed,

unbleached crystal is exposed to red _radiation, there is a

greater _probability of surface sites _being moved inside than

for internal sites _being moved to the surface. Upon _develop

ment with a surface _{acting developer,} a _density decrease is

Q

realized. This is true _only if the _trap to which the silver

atom is moved is equivalent to or deeper than the one from

which it originated.

The second _theory proposes the rehalogenation of

9

the Herschel bleached silver latent image. If the halogen

acceptance of the carrier medium is _low, the silver ion

produced when a photon is absorbed _by a latent-image cluster

can recombine with the positive holes _resulting in an image 10

loss. When halogen acceptors are present in the _film, the

recombination is prevented and the latent image remains intact.

The amount of quanta required to achieve the

Herschel effect _bleaching of a latent image has been estimated

to be to 1010 times the number of quanta as it took to

1 1

form it. One interpretation of this value _may be that it

12 represents the ratio of the crystal area to latent image area.

The quanta of each exposure can be calculated from the spectral

output of the source _using suitable a

thus the actual quanta ratio as well.

3a

Many different photographic _imaging effects have

been produced _using the Herschel effect and conventional 1 /

silver-halide films. _{By altering} the exposure _sequence,

it is possible to produce reversal _imaging, and sensitization

II 3M _Dry Silver

3M _Dry Silver is a _{negative-working} silver halide

based film system _{using incorporated chemistry} and thermal

activation of _{development. The} process was developed to

provide a rapid access system which did not require aqueous

processing chemistry. _{Dry Silver was} evolved from _taking

a _thermally induced silver _producing reaction and _making it

16 light sensitive (UV sensitive as well).

Dry Silver consists of a light-sensitive silver

halide in catalytic _proximity to the source of the image

17

forming silver compound which itself is insensitive to light.

The silver halide is used _only to produce latent images in

exposed areas which catalyze the _thermally initiated reaction

between a silver _soap and a _developing agent. The silver

halide is not _{significantly} consumed in the production of the

silver image. The image silver is supplied _by the silver _soap,

18

specifically silver behenate. In most respects this product

19 has characteristics similar to _equivalent, conventional films.

The silver halide emulsion can be precipitated _by

three different methods. The two-coat method forms the silver

halide at the interface between a _coating of silver behenate

20

and a _coating of potassium bromide. The preform method adds

a _separately precipitated silver halide to an emulsion of

9n

used in film manufacture. In this _method, the silver halide

is precipitated _{by the addition} of potassium bromide _directly

7^

to an emulsion _containing an excess of silver behenate.

After development of the _film, the silver halide remains

intact; no conventional fixation is accomplished. This

necessitates the use of _very small silver halide _crystals,

0/

<0.5 \im in _diameter, to maintain a low D-min in the processed

film. The use of such small crystals also limits the sensi

tivity of the film and helps maintain good resolution

25

(-300 lp/mm) . Dry Silver may also be dye sensitized to

9 ft provide desired spectral sensitivities.

The preferred carrier for _Dry Silver emulsions is

polyvinyl butyral. The use of this material helps maintain

27

the dimensional _stability of the image due to softening.

Cellulose acetate is used as a protective overcoat to prevent

the loss of reagents or the diffusion of harmful _substances,

such as _oxygen, into the film. Film treatments which _rely

on the diffusion of aqueous reagents into the emulsion are

also _prevented, such as the conventional fixation of silver

halide and the latent image experiment used to illustrate the

28 Debot effect.

The development of _Dry Silver is represented in

29

Fig. 1. The temperature required for standard development

30

is 127C/260F. Developers are hindered _phenols, weak anti

oxidants composed of double and triple benzene rings (see

5a

*-K _ ,.

+ _R'-OH - Ag + R'=0

N0 Ag+

<Ag>

Figure 1.

Dry Silver Development

Example 1

CH:

I

, OH i

CH-1

tC-1

CH:.

9

CH

Example 2

CH3 OH

OH _CH3

I I

-CHtj^j-C-CH;.

ch3

CH3

OH OH _OH,

CHtC ^N _-CHT ^s _-CHT

^^|

I I | CH3

CH3 CH3 CH3

Figure la.

in order to control the _activity of the developer at the

temperatures encountered _by the film. Hindered phenols

derive their _stability from the great difference between the

temperature of development and normal storage conditions

(dark _{storage, 22C/72F, 50%} RH).31'32

At the temperature

33

of _development, the _developing agents are quite reactive.

The proportions and concentrations of the _developing agents

used _directly affect the _sensitivity and _stability of both

processed and unprocessed material.

Development is accomplished _{by heating} the film

34

using one of several methods. The most common are a

heated roller and high temperature fluid. The heated roller

offers a _dry, simple and convenient means of processing. Its

performance, however, is inadequate for use in a rigorous

sensitometric investigation. Problems encountered with

cross-web _uniformity and frequent destruction of small film

35

strips made it unsuitable for use in this project. The

high-temperature fluid offers the best means of development

and is the method used _by 3M for _{testing Dry} Silver materials

This method requires a fluid which boils at a temperature far

above the desired _processing temperature and does not react

37

with the film's emulsion. The fluid used _by 3M is their

own product, FC-43, an inert fluorocarbon with a sufficiently

low vapor pressure to remain stable at development temperature

38 (actual _boiling point unspecified).

8

It _may be possible to use the Herschel effect to erase latent

images from the silver halides and retain _sensitivity so that

another _{image may be} exposed and developed in the undeveloped

regions of the first image.

A reversal image would be produced _{by prefogging}

a piece of film just to D-max and then _giving a red exposure

in an image-wise fashion. _{By exposing} just to D-max the

maximum tonal range of the film will be utilized. The minimum

exposure required to produce D-max should be used because the

additional, unnecessary latent images produced would require

additional exposure to bleach a given amount of density.

Regions _receiving exposure will decrease in developed _density

due to the destruction of surface latent image sites. Upon

42

EXPERIMENTAL

Dry Silver film 7842 (see Table 1.) was exposed in a modified Kodak 101 Process sensitometer. A Kodak #2 _step

tablet was held in contact with the film emulsion. An exposure

time of 5 sec. at an illuminance of 878 lux at the first film

plane (see Fig. 2.) resulted in an open gate exposure of

4390 lux-sec or LogH = 3.64. _This

exposure in combination

with the #2 _step tablet produced both D-min and D-max on one

film sample over 21 steps.

The film was processed _by immersion into a bath of

3M fluorocarbon FC-43 held at a temperature of 127.0C/260. 6F.

Development time was 30 seconds. The film was handled under

recommended safelights throughout the experimentation.

Densities were measured _using a Macbeth TD-504 _diffuse,

trans-44

mission densitometer.

Herschel effect exposures were accomplished _by

covering half of the sensitometric exposure and _replacing the sample into the sensitometer without the _step tablet. The desired filtration was placed in the sensitometer and the

shutter was held open for the required exposure time. Exposure

reciprocity was tested by locating the film sample at different distances from the source to _vary illuminance and _adjusting the

45

Ill Aim of _Research

Little research has been performed to determine how

Dry Silver materials respond to unusual photographic effects

often observed in conventional silver halide materials.

Research and development has been limited _primarily to the

characterization and perfection of the system for its intended

39

use as a _copying, data _recording and graphic arts material.

Any additional research into this system is desireable and

could have practical application. With this _system, the

Herschel effect could be used to produce some useful latent

image changes. _They include the erasure of _fog, add-on of

an image and the production of a reversal image.

The erasure of _fog would be accomplished _{by treating}

a fogged emulsion with red radiation before the _imaging

exposure. The red exposure would decrease _{fog by breaking}

up small _fog latent image centers. _Fog latent _images, how

ever, may not be directly interchangeable with latent images

caused _by an exposure which results in the same _density after

processing. This is because fog latent images are formed over

a _long period of time and are more stable than those caused

by an actual exposure to radiation.

The add-on of an image requires a material which

does not remove the light-sensitive material after the

10

Figure Z.

11

The output of the RLF sensitometer was calibrated

using an EG&G Photometer-radiometer set _up for both illuminance

and irradiance measurements. This was repeated with the

filters in place to _quantify their spectral transmittances.

A spectrosensitometer was used to determine the spectral

sensitivities of the films investigated. All exposures in

12

DISCUSSION OF EXPERIMENTAL

The actual _{experimentation performed differed}

radically from that _originally planned.47

This was a result

of unanticipated difficulties encountered with both materials

and equipment involved with the project. _Only the blue

sensitive (7842) _Dry Silver film was used for all the exper

imentation. This choice was based on measurements of the

spectral sensitivities of the three available films and the

spectral transmittances of the required filters. All of the

films exhibited residual sensitivities for _building latent

images upon post exposure to the _long wavelengths intended

48

for Herschel effect bleaching. Experimentation was first

performed _using the blue sensitive film because it had the

least _sensitivity to the red exposures and should therefore

exhibit the Herschel effect more _easily than the other films.

The blue sensitive _{film, 7842,} showed no _sensitivity

to wavelengths longer than 620nm under the test _conditions,

as seen from the spectrosensitometer exposures. The green

and panchromatic films, 7859 and 7869 _{respectively,} both

exhibited sensitivities to wavelengths beyond the _long wave

length limit of the spectrosensitometer (>720

-near IR) .

The Wratten filters #16 and #23A both transmit significant

13

respectively and were thus unsuitable for the Herschel effect

exposures with _any of the films.

The Wratten filters #70 and 87C seemed most ;

appropriate for the Herschel effect exposures. _However, most

experimentation used the 87C _filter, as most exposures _using

the 70 filter would result in _density increases.

The RLF sensitometer was used for both actinic _and,

with suitable _filtration, Herschel effect exposures. The

output of the tungsten source is _mostly in the red and infra

red region of the spectrum. With _filtration, it provides a

51 convenient, repeatable infrared source.

The set _up of a suitable process for _Dry Silver film

required the greatest effort. Initial experimentation _using

two different heat shoe/drive roll type _dry processors showed

that development _uniformity was inconsistent. This was

primarily due to variations in the speed of the roller

transport. This _processing method isn't _{wholly unuseable;}

however, the results obtained are less than _satisfactory for 52

use in a rigorous sensitometric investigation.

On recommendation from Morgan of _3M, an effort

was made to set _up a process _utilizing an inert

high-temper-ature fluid. This mode of _processing is used in the _Imaging

Research Laboratories of 3M. One gallon of fluorocarbon FC-43

was originally provided for this project. Unfortunately, the

temperature control bath available required a minimum of two

14

to function properly. Because the FC-43 was quite _expensive,

an effort was made to set _{up using} one gallon or less of the

fluid.

The temperature control bath was filled with

ethylene glycol _{(boiling point 192C) and a beaker of FC-43}

was immersed in the fluid. The FC-43 required circulation to

insure the _{repeatability} and _uniformity of development.

A pneumatic-magnetic stirrer and a propellor stirrer were

tried and required special film _handling procedures. Good

results were obtained with this set-up. _However, it was _very

inconvenient and tedious to use.

At this _point, an additional two gallons of FC-43

were _provided, and the temperature control bath was filled

with this liquid. This allowed the use of a _{simple, easy} to

use film holder and eliminated the noxious fumes of the

ethylene glycol and the _ungainly apparatus required _previously

The actinic exposure was chosen to produce both

D-min and D-max on the same film sample. The Herschel effect

exposures were determined empirically. _Initially, investigation

of the significance of both actinic and IR exposure _reciprocity

showed that longer exposure times produced _apparently better

results at a fixed exposure level. The shorter exposure times

caused the IR exposure to result in a _density increase. As

the exposure time was _increased, at the same _exposure, the

film showed a decrease in the amount of density build-up

after the IR exposure. The exposure time was lengthened until

15

a time was used which did not cause a _density increase.

At this _{point, the IR exposure was increased}

by lengthening

the exposure time at a fixed irradiance. The exposure was

increased in _{two-stop increments, and an exposure time} of

96 hours was used at the project's

termination.56

The design of the experiment yielded test strips

separated _{by many hours, and,} in several _instances, days.

Because of _this, it was impractical to process _immediately

after the termination of an exposure. Frequent operation of

the temperature control bath caused significant losses of

FC-43 due to evaporation. From the _beginning of the experi

ment all unprocessed _films, both exposed and _unexposed, were

stored under refrigeration for _processing together at a later

time. A test was devised to investigate _any latent image

changes which _{may have} resulted from such storage. At the

same time the effect of storage at both room temperature and

elevated temperature on test exposures was determined.

Standard sensitometric exposures were made over 5 consecutive

days and a portion was stored at 4.5 _C, 20 C and 50 C. All of

the strips were then processed in a random order in one

58

session.

The refrigeration test indicated no significant

change in film latent image during 5 days of storage (see

Fig. 3.). The test at 50 C showed a significant decrease in

film speed and an increase in contrast over the same length

16

D E N

S I T

2.8 -r

2.4__

2.0

--1.6

--1.2 -"

0.8

--0.4

--Refrigeration Test

Dry Silver 7842

C - _Control 1-21 hrs II - ₄₅

III - 73

IV - _94.5

4.5C

III

0.80 1.20 1.60 2.00 2.40 2.80

Log exposure _(lux-sec)

3.20 3.60

Figure 3.

17

2.8

->-Oven Test 50C

2.4 -- Dry

Silver 7842

C - _Control 1-21 hrs II - 45 III - ₇₃ IV - _94.5 V - 117

0.80 1.20 1.60 2.00 2.40 2.80

Log exposure (lux-sec)

3.20 3.60

Figure 4.

18

blue sensitive film _indicates normal latent image stability.

The lack of Herschel effect _bleaching could not be attributed

to an _{extraordinary} latent image _stability exhibited _only by

59

this film. These tests were required to provide justifica

tion _{for waiting} until several Herschel effect exposures had

been collected before _operating the high-temperature bath.

This resulted in a minimal loss of FC-43 _during the

. 60,61

experiment.

19

SUMMARY & CONCLUSIONS

The objective of this project was never achieved.

No _detectable Herschel effect _bleaching of latent image was

ever accomplished. On the _contrary, the _only post-exposure

change due to the infrared exposure was a _density increase.

This was a result of the conversion of sub-latent images to

full latent images _by the infrared exposure. A ratio of

3><106, red to actinic _quanta, was achieved in this _experiment,

ft *?

using a 96 hour exposure time ! Significant increases in

this ratio would have required _{prohibitively long} exposure

times and were thus not investigated. _Doubling the ratio

would require a _doubling of the exposure time. All exposures

were made at room temperature. No variation of the film

temperature _during the exposure was investigated.

The Herschel effect does not operate in this silver

halide system. The redistribution _theory of the Herschel

effect as reported by Debot, Falla,, Hautot, '

Eggert and

67

Heimann, was used as the theoretical basis for this project.

According to _them, the redistribution operates within an indi

vidual silver halide crystal and is independent of the emulsion

composition. The incident radiation acts to move a developable

surface latent image to an undevelopable internal site.

20

rehalogenation of the latent image silver as reported _by

6R

Farnell and Birch. This _{theory adequately} accounts for the

imaging effects observed in this project. The presence of

halogen acceptors in the _Dry Silver films would prevent the

rehalogenation from _{occuring, leaving} the latent image intact.

Heating this same emulsion would release the _{holes, promoting}

latent image fade at high temperatures. Both of these obser

vations are consistent with the experimental findings of this

project.

The emulsion composition was looked at to determine

the hole _{trapping ability} of its constituents. The _developing

agents used were found to be _{strong hole} traps. The benzene

ring structure is a _{strong halogen} acceptor and the hindered

71

phenols used as _developing agents include this structure.

The hindered phenols must be included in the emulsion in such

concentrations as to provide _fast, uniform and complete

development of the film. These same concentrations would be

sufficient to absorb significant quantities of photo-released

u 1 72

halogen.

The _long chain hydrocarbons used as emulsion

carriers, though not halogen acceptors, are strong absorbers

73

in the infrared. The hindered phenols are IR absorbers as

well, and, together, they act as an infrared filter, reducing

the number of infrared photons available for latent image

destruction. Together these two factors combine to effect

21

image in _Dry Silver films.

In _{conclusion, the} theoretical basis for this experi

ment was faulty. This film was chosen for its potential to

exhibit the useful effects of _{reversal, add-on,} and _fog

erasure _{simply by altering} the exposure sequence. The compo

sition of the _{film, however,} keeps the Herschel effect from

operating and _preventing the desired film response. Though

the objectives of this project were not _achieved, the results

are consistent with the recent work done in this field by

Farnell and Birch. This experiment adds further evidence

to their _theory of the Herschel effect as a rehalogenation

process the loss of latent image is the result of a

photo-induced _break-up of the latent image and subsequent rehalogen

22

23

LIST OF REFERENCES

1. _{Farnell, C.G., D.C.}

Birch, "The Herschel Effect as a

Rehalogenation Process,"

J. Photo. _{Sci, 27, 145,} (1979).

2. _{Hillson, P.J., "Literature Review of the Herschel} Effect,"

J. Photo. _{Sci, 10, 182, (1962).}

3. _ibid.

4. _{Saunders, V.I.,} R.W. _Tyler, W. _West, "Herschel Effect in Single Crystals of Silver Bromide,"

J. Chem. _Phys,

16, 206, (1966).

5. _{James, T.H.,} The _Theory of the Photographic _Process,

4th _{ed, MacMillan, New York, 1977,}

p 185.

6. _{Hillson, p 182.}

7. _{James, p 185.}

8. _{James, p} 184.

9. _{Farnell, p} 145.

10. ibid.

11. _{Hillson, p} 183.

12. _Francis, R. , Conversation, 5/5/82.

13. _Francis, R. , Lecture in R.I.T. course 0907-421, 9/10/80.

14. _{Hillson, pp} 182-186.

15. _Morgan, D.A. , 3M's Dry Silver Technology, Address to

Photoscientists of _Japan, 3M _Co., St _{Paul, Minnesota, p} 1.

16. ibid.

17. Barry, D.G., Dry Silver _Technology, 3M Microfilm Products

Division, 3M _Co., St _Paul, Minnesota, p 1.

18. Morgan, p 6 .

24

20. _Morgan, D.A. , 3M's Dry Silver _Technology, Presented at

Meeting of the institute of Image Electronics Engineers

of _{Japan, 3M}

Co., St _{Paul, Minnesota, 9/5/80, p} 2.

21. ibid.

22. _{Morgan, D.A., Conversation}

during visit to 3M _Imaging Research _Division, St _{Paul, Minnesota,} 3/16/82.

23. _{Morgan, p} 2.

24. Francis, R. , Lecture in R.I.T. course _0907-532, 12/8/81.

25. 3M Data Sheet for _Dry Silver Product 7842.

26. _{Barry, p} 1.

27. _{Morgan, p} 6.

28. _Mees, C.K.& T.H. _James, The _Theory of the Photographic

Process, 3rd ed, MacMillan, New _{York, 1966,} pp 158-9.

29. _{Barry, p} 2.

30. _{Morgan, p} 6.

31. _{Morgan, D.A.,} Telephone _{conversation,} 2/8/82.

32. 3M Data Sheets for _Dry Silver Products.

33. _{Morgan, telecon,} 2/8/82.

34. 3M Data _{Sheet, "Developing} 3M Brand _Dry Silver Films

and Papers," _January 1978.

35. _Cardinali, T., Laboratory Notebook, 3/20/82, pp 9-10.

36. _Morgan, conversation, 3/16/82.

37. ibid.

38. ibid.

39. Morgan, telecon, 10/2/82.

40. _Mees, p 342.

41. Francis, R. , Lecture in R.I.T. course 0907-531,

9/23/82-9/24/82.

25

43. _{Laboratory Notebook,}

4/16/82, p 31.

44. _{Laboratory Notebook,}

4/12/82, p 26.

45. _Laboratory

Notebook, 4/18/82, p 40.

46. _{Laboratory Notebook, 3/19/82,}

p 7.

47. _{Cardinali, T., "The Herschel Effect}

Bleaching of Latent

Image in 3M _Dry Silver Films,"

Proposal for _Research,

10/19/81, pp 9-14.

~

48. _{Laboratory Notebook, 4/6/82,}

p 20.

49. _{Laboratory Notebook, 3/31/82-4/2/82,}

pp 13-18.

50. _{Laboratory Notebook, 4/19/82, pp 42-45.}

51. _Francis, R. , Conversation, 5/13/82.

52. _{Laboratory Notebook, 3/20/82, pp} 9-10.

53. _{Morgan, Conversation, 3/16/82.}

54. _{Laboratory Notebook, 4/12/82-4/22/82, pp} 25-48.

55. _{Laboratory Notebook, 4/28/82, p} 50.

56. _{Laboratory Notebook,} 5/13/82, p 74.

57. _Laboratory Notebook, 5/4/82, p 57.

58. _Laboratory Notebook, 5/10/82, p 63.

59. _{laboratory Notebook,} 5/11/82, pp 69-70.

60. _{Laboratory Notebook,} 4/7/82, p 23.

61. _Hawksford, R. , Telephone conversation, 4/23/82.

62. Farnell, p 145 .

63. _{Laboratory Notebook,} 5/13/82, p 74.

64. Hillson, p 184 .

65. ibid .

66. ibid .

67. ibid .

26

69. _{Farnell, p 182.}

70. _{Farnell, p} 184.

71. _{Morgan, p} 6 .

72. _{Haist, G.,} Conversation at the 35th S.P.S.E. Convention,

Rochester, New _York, 5/13/82.

73. _{Westbrook, J., Conversation,} 5/17/82.

74. _Hardesty, R. , Telephone conversation, 5/17/82.

27

3M DRY SILVER FILMS

28

Film

(Lot _number)

7842

001x94001-15

7859

C002x43024

7869

31-1425

Spectral

sensitivity blue green pan

D-max 2.6 2.3 3.5

D-min 0.12 0.10 0.20

Gamma 1.7 1.3 3.0

Resolution

cycles/mm

300 250 300

Log E Range

ALogE from(Dmin+.04)

to(90% of Dmax)

1.8 1.6 1.7

Safelight filter 1A or low OC 1A 1A or low OC

Table 1.

29 r^ vo co ll cu X 4J o o to

o 00_o

i-H

H

I-l T-l tH

pj m CO 04 X X ro cO + o cu CO 00 c

O 1 ai

H X 4J

C 3 u

CU CM

H i-H cO

U e J-) _!-i

D o O CM S

CO ^* ctl r^

o co ^D r

CX C <r >

X o u; 4-> M

cu -< _4J r.

o II

o o O .O a

1-1 i-H X! T-t _{X o}

cu a ^ P H

Si X X o i-i U

o CH H

co o O vO CO

^1 00 00 10 o

CU .

CU <r a

X r-

r-CO o

X CO

Vi

CM _{a O 3}

cu E X CU o

Vi o cu CO XI

p ^-.

co CO _E o ^>

o C 3 CN O

a o u co

X " u 2 C

w o o o CTJ

r-t Si tH 3 ₁

u a cr ₁ 1

H X X CO 1

e CU CU CU

I-l m in Si M cu >-l

4-> ro ro 4-1 D u 2

O CO a CO

< CNI CM CW o CO o

O X o a, a X o cu X cu w

O co I-l i-i

is I-l CU o cu

C cu V-i.fi I-l Si

CU -U o CO o c o

acu . _a,co I-l CO O 00 ro E ^ J-l Vj

o cu o CU

+ O X < X

Table 2.

30

31

o

o o_o

co C O O CU co cu E i-i u cu 0 CO o a X cu 00 o pj X 3 cu o CO a H 00 o pj CN

Log exposure (lux-sec)

Figure 5.

32

-- 10.0

8.0

Relative Spectral _{Sensitivities}

of _{Dry Silver films}

360 400 440 480 520 560 600

Wavelength (nm)

640 680 720

Figure

33

3.

00--Spectral Output

RLF Sensitometer

(lamp current .805 amps)

2.

00--Output x 10 2

(watts/cm -nm)

1.00--400 500 600 700 800

Wavelength (nm)

900 1000 1100

Figure 7.

34

aO ^"^"^"^qO

y

/

<?

/ SAME CURVES

.^Oo^

LOG E

Figure 8.

36

VITA

Thomas Cardinali is a U.S. citizen born on _January

22, 1960 in _Fulton, N.Y. to Robert and Virginia. The youngest

son of a Cornell graduate in _chemistry, turned professional

photographer, an _{early intrest in both fields} was fostered.

In _1977, he spent the summer with a _family in _Pasching, Austria

on an American Field Service scholarship. Tom graduated with

honors from the G. _{Ray Bodley} H.S. in June 1978 and entered the

Photographic Science and Instrumentation program at the Roch

ester Institute of _Technology that fall. He felt this would

be an ideal combination of his intrests as well as _preparing

him for a career in the microelectronics industry. There he

chose electives within the Photoscience Division and maintained

a 3.30 G.P.A. In _1982, Tom was chosen to receive the Fuji

Scholarship for academic achievement _by a Photoscience senior.

Tom was employed _by the Photo Cage at R.I.T. and

during the summer of 1981 _by E.I. DuPont in Rochester, N.Y. as

a _Quality Control Technician in the Test Methods Division.

Tom is presently employed _by the International Business Machines

Corporation, in their General Technologies Division in Essex

Junction, Vermont as an engineer in the Mask House.

Tom is an avid motorcyclist and photographer, enjoys