Experimental Results

The DP3 Project is still in its experimental phase examining the effects of various environmental and use stresses on the different digital print types. As each set of experiments is completed and published, its results will be posted here. When all of the experimental work is completed, the results will then be converted to “best practices” for the care of these materials. Until then, users of this site can access the published data to date, through the following technical papers. Click on the link below to read the abstract or summary for each paper. The full text can then be accessed from the abstract.

General

Environmental Deterioration

Physical Stability

Enclosures

Disaster Response

Mixed Collections

Other Articles (No PDF available - see original source)

 

Beyond Lightfastness: Some Neglected Issues in Permanence of Digital Hardcopy

Daniel Burge, Andrea Venosa, Gene Salesin, Peter Adelstein, and James Reilly

This paper addresses physical print permanence issues beyond lightfastness and gas fastness for digital image hardcopy. Most image-life claims are based on time to unacceptable fade during high intensity exposure extrapolated to time under assumed display conditions in homes, offices, and other public areas. This neglects the potential for images to decay by other mechanisms (chemical or physical) which may, during actual use, be manifested before significant light-induced decay. Therefore, current practices of advertising image longevity by display-life have been woefully inadequate and potentially seriously misleading. The experimental work shows that inkjet prints can be sensitive to abrasion, surface cracking, and adherence to plastic page protectors in albums and glass in frames. Download the full paper in PDF format.

 

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Summary of the DP3 Project Survey of Digital Print Experience within Libraries, Archives, and Museums

Daniel Burge and Douglas Nishimura

In order to quantify the experience cultural heritage institutions have had or are having with digitally printed materials in or entering their collections, the Image Permanence Institute (IPI) conducted an online survey. The survey gathered data relevant to the collecting of digitally printed materials, deterioration of those materials, preservation policies regarding the care of those materials, and the use of digital printers in- house. The results indicate that most institutions are receiving digitally printed materials but that their staffs do not possess the necessary information and skills to identify or develop policies for the care and handling of these materials in their institutions. Unfortunately, the data also indicates that digitally printed materials in many institutions are already decaying and doing so by a variety of mechanisms. In addition to collecting digitally printed materials from outside sources, institutions are relying on digital printers to produce their own institutional publications, work copies, exhibition signage, etc. While some of this material is intended for short-term use, others, such as conservation documentation, may be needed for extended periods of time. Download the full paper in PDF format.

 

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What Do You Mean When You Say "Digital Print"?

Daniel Burge, Douglas Nishimura, and Mirasol Estrada

How would you define the term digital print? Would you say “all items generated from a digital printer”? Or “any print that was ‘born digital’”? Or “items printed on light sensitive photographic papers exposed using a digital photo printer”? If you answered “yes” to any or all of the above, you would not be off base. In fact, according to preliminary results of a recent survey, such varied answers appear to be creating a barrier to crafting a common definition for such materials, which has implications for the archives profession. In June 2008 the Image Permanence Institute (IPI) at the Rochester Institute of Technology (RIT) sent solicitations for an online questionnaire to a variety of cultural heritage institutions, private conservators, and related consultants to quantify field experiences related to caring for modern digitally printed materials. The results of the full survey will be published at a later date on IPI’s DP3 Project website. However, the responses to the questions regarding how to best define the term digital print were compelling enough to address here in the interim. Download the full paper in PDF format.

 

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Investigations into Potential Reactivity between Silver-Halide and Digitally Printed Photographic Images in Long-Term Storage

Daniel Burge and Lindsey Rima

The purpose of this project was to investigate the possibility that digital prints, i.e., electrophotographic, inkjet, and dye sublimation, stored in direct contact with silver-halide prints in mixed collections will cause accelerated degradation of the silver- halide prints. It cannot be assumed that these prints will be chemically compatible during long-term keeping. Since consumer collections of printed images may contain mixtures of both digital and traditional photographs, it is important that they do not adversely interact with one another. The method outlined in ISO 18916 Imaging Materials—Processed Imaging Materials— Photographic Activity Test for Enclosure Materials was used to predict potentially harmful interactions between these print types. Some digital prints were reactive with silver-halide prints while others were not. The fact that some digital print materials could degrade adjacent materials also suggests that their own chemical compositions are unstable in ways not previously identified; thus, results from this project should be useful for manufacturers looking to improve the formulations of their products. Download the full paper in PDF format.

 

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Selecting Suitable Enclosures for Digitally Printed Materials

Daniel Burge and Lindsey Rima

It cannot be assumed that storage enclosures considered safe for traditionally printed images and documents are suitable for modern, digitally printed materials. In this project, a large variety of digital print types were tested using a modified version of the ISO 18916 Imaging materials—Processed imaging materials—Photographic activity test for enclosure materials standard to assess the risk to digital prints by paper enclosures known to be inert or reactive with traditional photographic prints. The types of enclosures tested included buffered and non-buffered cotton papers, and groundwood paper. In addition, qualitative filter paper that had been wetted and dried with either an acidic or basic solution was also tested to determine the effects of enclosure pH on digitally printed materials. It was determined that, in general, digital prints tended to be less reactive with various enclosure types than traditional prints. Digital prints were most sensitive to paper that contained groundwood. The enclosure reactivity test results were then integrated with previous published work on the tendencies of various enclosure types to abrade, ferrotype, or block to digital prints in order to create a comprehensive set of recommendations for digital print storage enclosures. Download the full paper in PDF format.

 

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Tendency of Digitally Printed Materials to Ferrotype or Block

 

Lindsey Rima and Daniel Burge

This study was undertaken to quantify the tendency of modern, digitally printed photographs and documents to adhere to each other or adjacent surfaces in storage. It has long been known that the gelatin binder used in traditional photographic prints can stick to glass in framing packages as well as to many types of plastic sheeting used in storage enclosures. This has typically been attributed to exposure of the materials to high humidity such as found in tropical climates. In this test, a variety of digital print types were incubated at 30°C and 90% RH for seven days and then visually assessed for adherence to polyester, polypropylene, and polyvinyl chloride films; envelope paper; typical framing glass; and both the face and reverse sides of prints of the same type. All digital prints tested were less likely to block or ferrotype than traditional color photographic prints. Download the full paper in PDF format.

 

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Abrasion of Digital Reflection Prints

Eugene Salesin, Jessica Scott, Douglas Nishimura, Peter Adelstein, James Reilly, and Daniel Burge

An increasing number of color prints are now obtained from digital information with the hard copy being produced by ink jet, thermal dye transfer, and electrophotographic technologies. The permanence of these materials is of paramount concern. While there has been considerable investigation on the image stability of these materials, as it is affected by heat, humidity, light, and pollutants, there has been relatively little on their physical integrity. A physical property of primary interest is abrasion resistance. Damage to prints can occur when they are pulled from a stack or when they are accidentally subjected to rubbing action by other materials such as storage enclosures. This study was primarily concerned with the suitability of standard test methods for these materials. Abrasion resistance was evaluated using two standard abrasion tests; the Ugra Rub Test and the Sutherland® Rub Test. Experiments were made on ink jet prints on both swellable and microporous paper as well as on electrophotographic prints. The back side of one sheet of paper was rubbed against the image side of another, simulating a real-life situation. Additional abrading surfaces were a standard envelope paper, a smooth polyester sheet, and a relatively smooth abrasive cloth. Abrasion damage was determined by density change, by gloss change of a 1.0 density patch, by average grey levels, by delta E, and by the degree of smudging of colorants onto an adjacent Dmin area. These quantitative tests were compared to visual ratings. Both the Ugra and Sutherland tests produced similar abrasion actions, although the latter was more severe. Download the full paper in PDF format.

 

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Abrasion of Digital Reflection Prints: The Abrasiveness of Common Surfaces and the Vulnerability of Print Processes

Douglas Nishimura, Eugene Salesin, Peter Adelstein, and Daniel Burge

Very little is currently known about the care and handling of digitally printed materials. Even within the industry the man- ufacturers know very little about the care of the very things that they produce and sell. As a result, Image Permanence Institute (IPI) undertook its Digital Print Preservation Portal Project (DP3). The purpose of this paper is to describe two aspects of the abrasion studies done as part of the DP3 project and their impact on storage recommendations for digital print collections. Download the full paper in PDF format.

 

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The Scratch Sensitivity of Digital Reflection Prints

Eugene Salesin and Daniel Burge

An increasing number of prints produced by inkjet, dye sublimation and electrophotographic technologies are now being collected by museums, libraries and archives. While there has been considerable investigation on the image stability of these materials, there has been relatively little on their physical integrity. The research reported here is focused on their scratch sensitivity and a comparison to a previous study on their sensitivity to abrasion. The apparatus and methodology described in ISO 18922 was used to scratch prints produced by the wide variety of digital print technologies in use today. However, the evaluation technique described in the ISO document was found not to be useful for these materials. Image analysis equipment and software was found to be effective in quantifying scratch sensitivity and results from this analysis are presented. These provide data which show that the abrasion sensitivity of digital prints cannot be used to predict their sensitivity to scratches. Previous work showed that pigment prints were particularly sensitive to abrasion but other types were generally not. This investigation indicates that pigment prints as well as other types of digital prints are subject to scratch damage because of loss of image colorant. Download the full paper in PDF format.

 

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Brittleness of Digital Reflection Prints

Eugene Salesin, Daniel Burge, Peter Adelstein, and James Reilly

Although cracking of image layers and/or buckling of papers is a potential problem for some digital prints under adverse handling conditions, there has been little investigation of this behavior. This study reports the results of using the ISO standard Wedge Brittleness Test, originally developed for traditional photographic films and papers, to explore the relative sensitivities of a variety of digital print types at 23°C/15% RH and 50% RH. The quantitative measurement in this test is the largest diameter in a wedge at which cracking or buckling first occurs. This method proved to be suitable for digital prints and allowed the examination of specimens for cracks and buckling. Some prints required very close examination after being subjected to the applied stress because many of the resulting defects were microscopic. The relative severity of the resulting damage is also discussed. Results are reported for over two dozen unprinted papers as well as mid-density prints produced by ink jet, dye diffusion thermal transfer, offset lithography and electrophotographic printing methods as well as by the traditional wet chemical process. There were wide differences in behavior between materials. In general, as might be expected, damage was more severe with some papers at the lower humidity condition. Download the full paper in PDF format.

 

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The Cracking of Inkjet Colorant Receiver Layers on Exposure to Light

Eugene Salesin and Daniel Burge

The purpose of this investigation was to determine whether exposure to light or ozone increases the sensitivity of some inkjet printed images to surface cracking during handling. In previous studies, several inkjet print examples showed a potential for significant cracking and flaking of the image area when handled after exposure to light or ozone. In these new experiments, both printed and unprinted samples of inkjet papers were exposed in separate experiments to high intensity fluorescent, xenon light, or ozone. Both papers increased in cracking sensitivity due to light and ozone, but at different rates. Download the full paper in PDF format.

 

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The Determination of the Minimum Force to Initiate Abrasion Damage of Digitally Printed Documents and Photographs

Eugene Salesin and Daniel Burge

IPI has previously published studies ranking the relative sensitivities of various digital print types to abrasion. The purpose of these new experiments was to determine the exact minimum levels of force and number of abrasion cycles necessary to first induce damage to documents and photographs printed with digital technologies. The results are intended to help cultural heritage institutions that collect these materials develop policies for use and care to prevent damage to their collections. They may also benefit commercial services that offer prints made with these processes, manufacturers of the printers and media used to produce these materials, as well as artists and photographers. Download the full paper in PDF format.

 

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Light-induced cracking and abrasion of inkjet prints: Damage and mitigation

Andrea Venosa, Daniel Burge, Eugene Salesin

This study is part of a larger research project at the Image Permanence Institute dedicated to digital print preservation issues – the Digital Print Preservation Portal (DP3). Previous DP3 studies determined that certain digital print types are prone to cracking and/or abrasion, and that factors such as low relative humidity, pollutants, and light increase the brittleness of the ink-receiving layer of some inkjet papers. The purpose of this investigation was to explore if light also increases the propensity of inkjet prints to abrade, and to examine the potential of framing glazings to mitigate light-induced physical damage (cracking and abrasion) by attenuating some portion of the UV spectrum. Inkjet papers and prints were subjected to xenon lighting (to simulate daylight through window glass) without glazing, or in sealed framing packages with plain framing glass (soda-lime) or UV filtering glass. Before and after light exposure, brittleness, and abrasion resistance were evaluated independently using two tests: ISO 18907 (Imaging materials – Photographic films and papers – Wedge test for brittleness) and a rub test utilizing a Sutherland® Rub Tester. In this study, exposure to light increased the cracking and/or abrasion tendency of some specimens. The use of UV filtering glass reduced this light-induced propensity in all cases. Plain glass protected all samples from at least one of these two types of surface damage, but was less effective than UV glass. Light-induced brittleness and sensitivity to abrasion were mostly, though not exclusively, caused by UV radiation. It was also seen that some prints may become brittle and/or prone to abrasion in the absence of image fade. Budgeting the amount of light these objects can be exposed to, protecting them from UV radiation, and handling prints with caution especially after exhibition, is essential in order to limit physical damage. Download the full paper in PDF format.

 

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Short-Term High Humidity Bleed in Digital Reflection Prints

Eugene Salesin, Daniel Burge, Douglas Nishimura, and Nino Gordeladze

Exposure of some digital print types to high humidity can cause image colorant migration resulting in image density changes, color shift, blurring and loss of detail. The purpose of this study was to quantify the potential for colorant bleed during short-term exposures to high humidity conditions in order to develop care and use guidelines for museums, libraries and archives that may collect large numbers of these materials including many of high monetary value. Most previous work has focused on image effects, but this project also includes tests for damage to text-based documents. The potential for bleed both parallel and perpendicular to the printer paper feed direction was examined. A variety of digitally printed materials, including inkjet, electrophotographic, and dye sublimation were exposed to high humidity conditions for two and four weeks. Results are reported as Delta E for a checkerboard target, change in width for lines both parallel and perpendicular to the paper feed direction, as well as text readability which was assessed visually. The relative sensitivities of the materials are ranked and compared to the sensitivities of traditionally printed offset lithography and chromogenic photo materials.. Download the full paper in PDF format.

 

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Effects of Ozone on the Various Digital Print Technologies: Photographs and Documents

Daniel Burge, Nino Gordeladze, Jean-Louis Bigourdan, and Douglas Nishimura

The harmful effects of ozone on inkjet photographs have been well documented. This project expands on that research by performing ozone tests on a greater variety of digital prints including colour electrophotographic and dye sublimation. The sensitivities of these materials are compared to traditionally printed materials (black-and-white electrophotographic, colour photographic and offset lithographic) to determine if the digital prints require special care practices. In general, the digital prints were more sensitive to ozone than traditional prints. Dye inkjet prints were more sensitive to fade than pigment inkjet, though pigment was not immune. The dye sublimation, colour electrophotographic (dry and liquid toner), and traditional print systems were relatively resistant to ozone. Text-based documents were evaluated in addition to photographic images, since little work has been done to determine if the type of object (image or text) has an impact on its sensitivity to ozone. The results showed that documents can be more resistant to ozone than photographs even when created using the same printer and inks. It is recommended that cultural heritage institutions not expose their porous-coated, dye-based inkjet photos to open air for extended periods of time. Other inkjet prints should be monitored for early signs of change. Download the full paper in PDF format.

 

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Effects of Nitrogen Dioxide on the Various Digital Print Technologies: Photographs and Documents

Daniel Burge, Nino Gordeladze, Jean-Louis Bigourdan, and Douglas Nishimura

The purpose of this study was to survey the most common types of digital print materials to determine their resistance to fade or yellowing by nitrogen dioxide (NO2), a pollutant commonly found in indoor environments to different degrees. For this experiment, various types of inkjet, dye sublimation, and electrophotographic prints (including digital press) were exposed to 5 ppm NO2 for four weeks. The sensitivities of the digital prints were then compared to those of traditionally printed materials (black-and-white electrophotographic, color photographic, and offset lithographic). Inkjet dye inks and the color dyes in traditional photographic prints were the most prone to fade by NO2. Traditional photographic, digital press, and offset lithographic papers were the most prone to yellowing by NO2. Black colorants were fairly robust indicating that most text-only documents should be very resistant to NO2 induced fade, though the papers may still yellow. Additionally, some inkjet dyes bled slightly to severely, depending on the printer and paper combination, causing the prints to appear discolored and blurred. This could result in loss of detail in images or a reduction in the readability of text in documents. This effect has not been reported with ozone exposures. Download the full paper in PDF format.

 

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Further Studies Toward Assessing the Risk of Damage to Digital Prints During Flood Events

Daniel Burge and Jessica Scott

This article is intended to provide significant improve- ments to the existing ISO standardized test method for evaluating the flood resistance of digital prints. The current method, 18935– 2005 Imaging materials: Colour images on paper prints: Determination of indoor water resistance of printed colour images, is useful for the evaluation of consumer products but is inadequate for the needs of cultural heritage institutions and the preservation of their collections. These collections contain both pictorial images and documents that are saved for their information content or aesthetic value (or both). Several digital print types were tested with variation in soak time, measurement types, and assessment criteria. The final result of this project is a new test method with expanded evaluation criteria. Download the full paper in PDF format.

 

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Core Concepts in Disaster Preparedness, Response, and Recovery for Inkjet-Printed Photographs and Fine Art

Daniel Burge

Large numbers of inkjet prints are already in collections. Unfortunately, many are considerably more sensitive to water damage than traditional prints, and some may even harm adjacent materials during water emergencies. Existing research suggests that inkjet prints immersed in water are prone to bleed, cracking, delamination, blocking, etc. Each damage type is highly dependent on the colorants used as well as the chemical and physical nature of the papers. While preliminary work has ranked the sensitivities of various inkjet types and evaluated potential methods for drying, a full understanding of how the materials will behave from small spills to prolonged immersions, in dirty or salt waters, as well as during exposure to extreme relative humidities, has yet to be performed (Burge & Scott, 2010 ; Jürgens & Schempp, 2010 ). Research at IPI over the last three years on the effects of water  xposure and techniques for recovery has led to the following core concepts for the salvage of inkjet prints during water emergencies. Download the full paper in PDF format. Download the Poster.

 

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The Effects of Various Adhesives on Dye and Pigment-based Inkjet and Dye Sublimation Prints

Nino Gordeladze, Daniel Burge, and Andrea Venosa

This study explored the reactivity of various adhesives on dye and pigment inkjet and dye sublimation prints. Consumers have reported adverse experiences including colorant bleed and yellowing in areas that were in contact with mounting adhesives. An accelerated test was conducted to study chemical interactions that might result in colorant fade, colorant bleed, yellowing, adhesive transfer or physical distortions of the digital prints. Fourteen different adhesives were applied to fine art, polymer and microporous photo papers, inkjet-sized and plain document papers, and dye sublimation paper. Images were printed on the photo and document papers using various inkjet printers and on the dye sublimation paper using a dye sublimation printer. The types of adhesives tested included water-based liquids, pressure sensitive tapes, laminating films, self-sticking notes and spray photo-mounting adhesives. The test combinations included prints without adhesives, prints with adhesives kept at room conditions (21°C and 50% RH) and prints with adhesives incubated at 70°C and 50% RH for 84 days as specified by ISO 18932 Imaging materials—Adhesive mounting systems—Specifications. This study provides a better understanding of the vulnerability of inkjet and dye sublimation materials to certain types of adhesives. The results showed colorant bleed, yellowing, adhesive transfer and physical distortions of the digitally printed materials can be caused by some of the adhesives tested in this study. Download the full paper in PDF format.

 

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Mitigation of Pollution-induced Deterioration of Digital Prints through the Use of Enclosures

Daniel Burge and Andrew Lerwill

The potential for common enclosures to reduce or prevent pollutant-induced deterioration of inkjet materials was investigated, with the specific research question being: Can any of the various commonly-used enclosure designs and materials (envelopes/boxes, paper/plastics) be used to effectively reduce or prevent the damage to digital prints caused by Ozone or Nitrogen Dioxide air pollution? The results indicate clear guidelines how to best proceed to mitigate pollutant gas damage. Polyester sleeves show by far the greatest potential for both pollutants over all tests conducted, which indicates this benefit may extend to the parts-per-billion range. Increasing ppm values and equally reducing exposure times to create the same ppm-days exposure did not always result in the same color change to the prints inside or outside enclosures. This importantly indicates extended time periods and lower concentrations could mean an enclosure’s effectiveness in preventing damage from pollution could be in fact much lower than that observed in highly accelerated testing (as seen in this work and elsewhere). This raises questions regarding the suitability of such techniques to appraise the efficacy of enclosures employed to deter pollution damage caused over longer periods (decades) at real world environmental pollution levels. Download the full paper in PDF format.

 

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Review of Research at RIT Comparing the Print Value and Permanence of Digital Prints vs. Offset Lithography and Silver-Halide Prints

Daniel Burge, Susan Farnand and Franziska Frey

Both print value and permanence are critical to consumer satisfaction of printed images. Over the last four years, the Printing Industry Center and Image Permanence Institute at the Rochester Institute of Technology have published a variety of studies evaluating the print value and permanence of inkjet and electrophotographic prints and compared their performance to the traditional printing technologies of offset lithography and color silver-halide photography. This paper reviews the published work to date. Download the full paper in PDF format.

 

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Effect of Light on Modern Digital Prints: Photographs and Documents

Andrea Venosa, Daniel Burge, and Douglas Nishimura

This project examines the light fastness of prints created with the most commonly used digital technologies (inkjet, color electrophotography, dye sublimation and digital press) along with prints created using traditional technologies (color photography, black-and-white (B&W) electrophotography and offset lithography). The inclusion of traditional prints provides benchmarks for collection care professionals to better gauge the significance of the results. In this study, prints were subjected to two types of lighting used independently to simulate daylight through window glass and artificial indoor illumination. Five aspects of light damage were assessed: fade in the mid-tone neutral, fade in the darkest neutral tone, paper yellowing, changes in paper gloss and text readability. In general digital prints were less sensitive to light than traditional prints; but each digital printing technology produced at least one sample that performed worse than its traditional benchmark in at least one of the aspects of light damage studied. Therefore, it is recommended that cultural heritage institutions strive to provide the most benign environment possible, taking display practices currently in use for traditional prints as a minimum starting point for the care of digital prints. Close monitoring for signs of change is also recommended. Download the full paper in PDF format.

 

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The Light Induced Deterioration Of Inkjet Media in Frames

Eugene Salesin and Daniel Burge

Previous research has indicated that airborne pollutants can cause physical damage to inkjet print media. This study was initiated to determine if inkjet media enclosed in sealed windowglass-covered frames could generate volatile reducing or oxidizing agents (redox agents) when exposed to light which could potentially cause such damage. An additional objective was to determine if the attenuation of UV energy by window glass in frames could mitigate previously observed damage of ink-receiver layers (IRL) and whether glass-covered sealed and unsealed frames would produce different results. Because of the dual objectives, this was a study in two parts. Results of the first part of this investigation indicated that a resin-coated (RC) black-and-white silver-gelatin photographic print, included as a control, produced the largest change in a redox detector. One of the two inkjet photo papers included in this study also produced a noticeable change, but to a lesser degree. The detectors with the other inkjet photo paper and the polyester film control showed no noticeable change. In the second study, the same two unprinted inkjet papers were exposed to 50 kilolux xenon light for twelve weeks, each in three separate framing configurations. One frame was sealed with its glass cover identical to the frames in the first experiment but without the redox detector film. Another had a glass cover like the first configuration, but the glass was spaced slightly above the papers and was open on all four sides to allow for ingress of ambient air. The third configuration did not have a glass cover. Results of the second investigation indicated that glass reduced physical damage caused by light for both inkjet photo papers. However, the open frame produced the greatest reduction in cracking in the inkjet paper that showed a noticeable change in the redox detector in the first investigation; much more than the closed frame. This might have been because the volatile redox agents generated during exposure to light escaped from the open frame. The other paper buckled in the tightest wedge setting of the brittleness apparatus (near complete fold). This failure occurred in the paper support and was not the result of exposure to light because unexposed paper showed the same result. However, the IRL in this paper completely disintegrated after exposure to light in the frame that did not include a glass cover. A larger study should be done to include a wider variety of inkjet papers to determine if the generation of redox agents in closed frames is a widespread phenomenon or whether it is limited to only a few. This additional investigation
should include the frame variations used in this study. Download the full paper in PDF format.

 

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Further Observations of Ozone and Nitrogen Dioxide Pre-Dosed Digital Prints Over Time

Nino Gordeladze, Daniel Burge, and Brian M. Gamm

There have been numerous reports on the effects of atmospheric pollutants on digitally printed materials that describe fading of colorants, yellowing of substrates, colorant bleed, and delamination of the ink-receiving layer on some digital prints. In 2010, the Image Permanence Institute published the results of an experiment on the effects of ozone and nitrogen dioxide on various digital print types. While it was not the intent of that experiment to determine the long-term effects of pre-exposure to pollutants, it was discovered after publishing the research that some of the samples dramatically yellowed while in storage. This research studied how those same digital prints stored at controlled room conditions changed after being exposed to ozone or nitrogen dioxide prior to storage. The yellowing of papers exposed to ozone before storage was previously documented in studies directed toward the development of test methods for accelerated aging. This paper documents real-time observation of digital prints after several hundred days in storage and addresses the potential damage to digital prints over time after exposure to ozone or nitrogen dioxide. The test samples included inkjet, color and black-and-white electrophotography, dye sublimation, digital press, chromogenic, and offset lithography prints. Paper yellowing, colorant change, further colorant bleed, and additional disintegration of the colorant layer of some prints were observed. Porous-coated materials exposed to ozone yellowed more dramatically in storage than when under direct exposure. This illustrates that initial results of change in these materials do not describe the whole story. Download the full paper in PDF format.

 

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Mitigation of Pollution-Induced Deterioration of Digital Prints through Low-Temperature Storage

Daniel Burge, Nino Gordeladze, Douglas Nishimura, and Jean-Louis Bigourdan

Results of an IPI survey showed that most museums, libraries and archives already have digital prints in their collections and that they are concerned about increasing influxes of these materials. The survey also showed that objectionable deterioration has already occurred to at least some of their prints including fading, yellowing, color bleed, surface cracking, and delamination. In total, 71% of institutions have already experienced deterioration in their digital print collections. Previous experimental research, both by IPI and others, has been able to establish a clear connection between ozone and nitrogen dioxide exposure and each of those forms of decay. Therefore, development of effective methods to mitigate such damage will be critical to the survival of these objects for future generations. This study was aimed specifically at determining the efficacy of one particular approach, which is mitigating pollutant damage to digital prints through lowered-temperature storage. Since deterioration due to pollutants occurs through chemical reactions, it may be possible to slow decay through cool or cold storage. Download the full paper in PDF format.

 

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The Determination of Humidity Limits to Prevent Colorant Bleed in Inkjet Prints

Eugene Salesin and Daniel Burge

The purpose of the project was to determine the absolute ceiling limits for temperature, humidity, and time combinations to prevent noticeable colorant bleed in photographs and documents printed with inkjet digital technologies. The research focused on a variety of dye printers and papers because it was known from previous work that these printer/paper combinations produced prints sensitive to humidity. The results of this work are intended to help cultural heritage institutions that collect these materials develop policies for use and care to prevent damage to their collections. The results may also benefit commercial services that offer prints made with these processes, as well as artists and photographers and the general public. Download the full paper in PDF format.

 

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Colorant Fade and Page Yellowing of Bound and Unbound Materials Printed Using Digital Presses and Offset Lithography when Exposed to O3 or NO2

Nino Gordeladze and Daniel Burge

The printing industry has seen growth in the number of bound digitally-printed materials since the introduction of commercial digital presses. Many short-run publications, such as research monographs, periodicals, and books have already entered the collections of cultural heritage institutions. It is vital that information be made available regarding the care of these materials. There is no known previous research on the effects of pollutants, such as O3 (ozone) or NO2 (nitrogen dioxide), on bound digitally-printed materials. This study was undertaken to specifically investigate the susceptibility of digital press and offset printed bound materials to page yellowing and colorant change when exposed to O3 and NO2 independently. The research findings demonstrated that bound digitally-printed materials are at risk to damage by these airborne pollutants. Cultural heritage institutions that have these materials within their collections should take precautions to mitigate deterioration through the use of air filtration, reduced temperature storage, or low permeability enclosures. The method chosen should match the use and size of the collection and the resources of the institution. Download the full paper in PDF format.

 

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The Determination of the Minimum Force to Initiate Abrasion Damage of Digital Press Prints

Eugene Salesin and Daniel Burge

The purpose of the project was to determine the minimum levels of force and abrasion cycles necessary to produce a just noticeable difference (JND) in objects printed with modern digital presses (documents, book pages, etc.). The results of this work are intended to help cultural heritage institutions that collect these materials develop policies for use and care to prevent damage to their collections. A variety of digital press technologies (dry- and liquid-toner electrophotography and inkjet) and papers (uncoated and glossy) were studied. These were compared to prints made using offset lithography. Specimens were abraded with both ¼-lb and 2-lb loads. The lighter weight was an attempt to replicate physical handling of materials such as page turning in books or sorting sheets in stacks of documents. The use of the heavier weight was an attempt to emulate unbound prints being pulled from large stacks as well as prints in stacks during transport. The abrading surfaces included unprinted and printed sheets to replicate single-sided prints in stacks or double-sided prints in stacks or books. A series of abrasion cycles (1 to 1000) were performed for each of the materials to determine when JND would be observed. The assessment included measuring colorant smear from a black printed area to an adjacent white area, loss of colorant from the black area, change in gloss from the black area and transfer of colorant to an adjacent sheet. Results from the ¼ lb. weight indicated that page turning for books or sorting of loose sheets in stacks should not be a problem for dry- and liquid toner electrophotographic printed materials as no noticeable damage was observed by either measurement or visual assessment even after many hundreds of abrasion cycles. The 2 lb. weight results showed differentiation between the different printer technology/paper combinations indicating a greater concern for objects that may be inadvertently subjected to higher forces, especially with digital press inkjet technology. Download the full paper in PDF format.

 

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Lessons in Digital Print Preservation: The DP3 Project

Douglas Nishimura

The Digital Print Preservation Portal (DP3) project was a three-year effort funded by both the Andrew W. Mellon Foundation and the Institute for Museum and Library Services. The project consisted of two parts: the portal and the research. The portal is a web-based information resource where information about the care and handling of digitally printed materials has been organized and made available to the public. Research papers coming out of the DP3 project as well as announcements of future DP3-related talks are also posted to the site. In addition, related information is available such as tools to aid in the identification of digital print processes. The portal can be found at http://www.dp3project.org. The research part of DP3 is an experimental program, based on work already done by industry and presented at ISO standards meetings, and designed to explore beyond what is currently known. The primary driver of this research was the practical information required by institutions in order to care for their digitally printed collection materials. Unlike the work of ISO TC42/WG5/TG3, the DP3 included graphic documents in the form of text targets in addition to photograph-like images. It was not necessarily expected that final answers would come out of this research, but at the very least, a better understanding of where to concentrate efforts and resources for future initiatives would be determined.

Douglas Nishimura in Topics in Photograph Conservation, Photographic Materials Group, the America Institute or Conservation of Artistic and Historic Works Volume Fourteen 2011

 

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Resistance of Digitally and Traditionally Printed Materials to Bleed, Delamination, Gloss Change, and Planar Distortion during Flood

Daniel Burge and Jessica Scott

It is imperative that cultural heritage institutions with digitally printed materials in their collections understand the sensitivities of these objects to water exposure during flood. Anecdotal evidence from institutions and the general public suggest that some digital print processes are extremely sensitive to water exposure. Understanding this vulnerability will be critical for institutions in modernizing their disaster response plans to include digital prints; inappropriate response could lead to loss of material due to its inherent sensitivity to water or due to contamination of adjacent collection materials through bleeding of the image-forming colorants. A variety of digital print types were immersed in water for 24 hours and then evaluated by measuring changes in color and gloss, and inspecting text readability, delamination, and or planar distortion. As expected, most prints experienced at least slight planar distortion; some, however, suffered extreme forms of damage including colorant bleed or complete delamination or dissolution of the image/text layer. Because the digital prints were often more sensitive than traditional prints to flood damage, results indicate that new flood response strategies should be developed for collections that contain these materials.

Daniel Burge and Jessica Scott in the Journal of the America Institute or Conservation of Artistic and Historic Works, Vol. 51, No. 2 Fall/Winter 2012

 

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Imaging Methods and Quantitative Measurements for the Characterization of Digitally Printed Materials

Daniel Burge, Nino Gordeladze, Kristin Smith, Jordan Briscoe, Ryan Boatright and James Reilly

Over the last five years, researchers at the Image Permanence Institute at the Rochester Institute of Technology have been developing an imaging strategy and a set of quantitative measurements that can be used to characterize modern digital print materials (both images and documents). While the goal of the project has ultimately been to enable personnel in cultural heritage institutions to identify their collection materials, the approaches should also be helpful to the field of forensic document examination. The imaging methods include varying the angle of lighting as well as the level of magnification. Structures such as surface gloss and texture as well as dot morphology and pattern can be assessed and compared to known print types. Additional, unique traits such as colorant bronzing, differential gloss, anti-block layers, etc. can also be used to narrow down the identification of particular print examples. This paper will describe the main approaches used for both imaging and quantitative measurement of print samples along with descriptions of where support tools can be found online.

Daniel Burge, Nino Gordeladze, Kristin Smith, Jordan Briscoe, Ryan Boatright and James Reilly in the Journal of the American Society of Questioned Document Examiners, Vol. 16 No. 1 June 2013

 

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Mitigation of light-induced damage on modern digital prints: Photographs and documents

Andrea Venose, Daniel Burge, Douglas Nishimura

This study is part of a larger research project dedicated to digital print preservation issues – the Digital Print Preservation Portal (DP3). This work quantifies the potential of glazing materials to mitigate different types of light-induced damage – colorant fade, paper yellowing, changes in paper gloss, and loss of optical brightening agent (OBA) function – that occur to digitally printed photographs and documents when on display. Prints were subjected to xenon lighting to simulate daylight through window glass in a series of arrangements: without glazing, with plain framing glass (soda-lime) in a sealed or unsealed package and with UV blocking glass in a sealed or unsealed package. Sealed packages served the purpose of isolating the samples from atmospheric pollutants, known to contribute to the deterioration of certain print types. In this study, the use of UV-filtering glass protected prints from colorant fade, paper yellowing, and paper gloss change to a significant extent. Protection conveyed by plain glass was less comprehensive and less effective than UV glass. Neither type of glazing was able to keep the OBAs functional by the end of the light exposure. It was also seen that light-induced damage to digital prints is due not only to UV radiation, but also to visible light, and that different digital prints may be more vulnerable to one or the other. Protecting sensitive prints from UV radiation and budgeting the amount of light they may be exposed to should be essential to any print display policy in order to ensure longevity.

Andrea Venose, Daniel Burge, and Douglas Nishimura in Studies in Conservation: Received May 2014; revised paper accepted November 2014. Download the full paper in PDF format.

 

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Safety of Freezing Inkjet Prints for Long Term Storage

Ivey Barker and Daniel Burge

Through the history of inkjet printing, a wide variety of colorants, coatings, and supports have been used to create fine art and professional photographs collected by museums and other cultural institutions. These materials have shown, through anecdotal experience as well as scientific study, a high degree of variability with respect to decay under room condition storage. Theory, as well as experimentation, has indicated that progressively lower storage temperatures should result in progressively longer lifespans. However, there is concern that crossing the threshold into freezing conditions could have adverse effects on the image quality of prints or the physical integrity of coatings and supports as has been found with other fine art and photographic materials through history. The experiments in this project investigated whether freezing and thawing would significantly alter the physical integrity or visual appearance of inkjet prints. Printed targets and non-printed sheets were tested for a variety of common deterioration forms including ink bleed, paper yellowing, change in gloss, coating embrittlement, and increase in abrasion sensitivity. Non-frozen controls and samples that had been frozen at -12° Celsius for one week and then thawed were tested and compared for the above types of decay. The freezing and thawing was shown to have no adverse effects on the prints. Freezing conditions can therefore be used as a storage option to maximize life expectancy for these materials. Validation of the use of below freezing temperature storage conditions for these materials is a critical addition to the literature on the subject of inkjet print care.

IS&T’s International Symposium on Technologies for Digital Photo Fulfillment, September 15-16, 2016 Manchester, UK. Download the full paper in PDF format.

 

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A Guide for the Assessment and Mitigation of Bleed, Gloss Change, and Mold in Inkjet Prints During High-Humidity Conditions

Jennifer Burger and Daniel Burge

The purpose of this project was to define the absolute ceiling limits for time and relative humidity (RH) combinations at room temperature to prevent damage to inkjet printed materials in museums, libraries, and archives when they are inadvertently exposed to short-term high-humidity conditions (under 28 days). Unintentional elevated humidity exposure can occur during HVAC malfunctions, transport, following water emergencies, and in uncontrolled storage or exhibition areas. Previous research has shown that colorant bleed, gloss change, and mold germination are the three most common forms of inkjet deterioration during high-humidity conditions. In order to provide collections care professionals with the necessary information to mitigate all three deterioration types, time limits for each needed to be compiled into a single, concise guide. Data on ink bleed and mold germination limits were collected from previous research, while the gloss change data required further experimental investigation. Gloss change experiments were performed with dye on polymer-coated RC paper, as previous studies have shown this ink/paper combination to be particularly sensitive to gloss change during exposure to elevated humidity. During the tests, samples were exposed to a series of time and RH variations. The results showed that while prints can be sensitive to gloss change at elevated humidities, inkjet prints are even more sensitive to colorant bleed, which is therefore the limiting factor. A guide for RH deterioration mitigation was developed and can now be used to predict how prints have or will respond to elevated humidity exposure for times less than 28 days. While all inkjet print types should be safe at humidities at or below 65% for up to 28 days, relative humidity exposures above 80% should be avoided at all costs as the most sensitive print types will likely be damaged within 24 hours. The guide provides predictive times to damage for RH values between 65% and 80% that can be interpolated to determine risk at these intermediate conditions.

IS&T’s International Symposium on Technologies for Digital Photo Fulfillment, September 15-16, 2016 Manchester, UK. Download the full paper in PDF format.

 

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