Over the years, technical innovation in the physics of electrophotography has had mixed results in influencing the technology. Four examples familiar to the author will be discussed and their current and potential future influences on the electrophotographic technology will be described. (1) The introduction of the theory of magnetic brush development had only limited influence on the invention of improved variants. However, it had an enormous influence on the perception that electrophotography was a logical and predictable technology that could be understood with common scientific tools. (2) The introduction and implementation of the ideas of the proximity theory of toner adhesion has allowed the design of the smallest size lowest cost color electrophotographic engine which will be commercially available soon. (3) The demonstration that toner charging is due to Kondo's high density theory surprisingly has failed to help toner material scientists redesign toners; in particular, it has failed to help them design a toner with a narrower charge distribution. Such a narrow-charge distribution toner would allow the average toner charge-to-mass ratio to be reduced, which would be useful in many of the electrophotographic subsystems. Combining a narrow-charge distribution toner with the methods of reducing the toner adhesion based on the proximity theory could lead to a new generation of marking engines based on novel marking technologies. Finally, (4) progress has been made recently in identifying the mechanism by which holes move through photoreceptors. The author conjectures that elucidation of the charge transport mechanism will be beneficial to the design of organic photoreceptors for electrophotographic systems as well as other organic electronic devices. Although today's photoreceptors have adequate mobility, increased process speed will require both higher mobility and a reduction in those factors giving rise to carrier range limitations. For organic electronics higher mobility materials are necessary for practical devices.

Toner is a critical material in printing and copying processes. Compared to the conventional pulverized toner, polymerized emulsion aggregation (EA) toner provides more precise control over the shape and surface roughness of particles. Due to its roundness and low surface roughness, the near-spherical EA toner appears to adhere more strongly to flat substrates, which is desirable for efficient toner transfer and development. However, in the cleaning and transport processes, due to enhanced adhesion, it is difficult to remove the residual EA toner from surfaces of the photoreceptor and transport belt. To reduce the adhesion of the EA toner in a controllable manner, the surfaces of the toner particles are coated with silica nanoparticles with a diameter range of 15–32 nm. In the current study, a technique based on the rolling resistance moment of the particle-substrate adhesion bond is utilized for quantifying the effect of nanoparticle surface coating on the adhesion of individual toner particles. With the aid of a custom-made nanomanipulation system, an increasing lateral pushing force was applied to an individual toner particle adhered to a silicon substrate while the pre-rolling and rolling motions of the particle in response to the lateral pushing force were recorded. The work of adhesion between the toner particle and silicon substrate was extracted from the corresponding lateral force-particle displacement curve. The technique was used to characterize the adhesion properties of both uncoated (bare) and nanoparticle-coated model toner particles with a specified surface area coverage of 50%. It is found that the work of adhesion values between the surface-coated experimental toner particles and the silicon substrate are almost an order of magnitude lower than those for the bare ones.

Certain leuco dyestuffs are known to exhibit a brilliant color by reaction with a phenolic developer; 2-[(4-hydro-xyphenyl)sulfonyl]-phenol (BPS) is a well-known developer for black leuco dyes such as 6'-(diethylamino)-3'-methyl-2'-(phenylamino)-spiro[isobenzofuran-1(3H), 9'-[9H]-xanhen]-3-one (ODB) in thermosensitive papers. Although BPS is a small molecule (molecular weight: about 250), it is thermally stable as characterized by a high melting point of about 184°C. Furthermore, the stability of BPS is also extended to the 1:1 "leuco/developer" system. In this connection, structure analysis of BPS has been carried out in order to elucidate the stability of BPS itself as well as its leuco/developer system. Then, we found that one BPS molecule is hydrogen bonded to four different neighboring ones, forming an OH···O two-dimensional hydrogen-bond network. This ensures a high thermal stability of BPS. On the other hand, in the ODB/BPS system, only one of the four hydrogen bonds in BPS is used for the formation of the 1:1 ODB/BPS colorant while the remaining three hydrogen bonds keep the network. As for the tinctorial strength in spin-coated ODB/BPS, the color intensity is found to be limited to about 70% of the maximum available value. This is because there is a fraction of ODB molecules, whose lactone ring is still closed owing to the steric hindrance.

This article is intended to provide significant improvements 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.

Vaterite is a crystal polymorph of calcium carbonate that is widely used in various industries, but rarely occurs in nature. This article presents an effective method for application of vaterite-type calcium carbonate as a coating pigment for ink jet paper instead of silica. Vaterite was prepared by mixing and agitating K₂CO₃ and CaCl₂ solutions with an ultrasonic homogenizer. The vaterite crystal stability was examined to achieve vaterite properties appropriate for ink jet application. A high pH reduced transformation from vaterite to calcite because of the low solubility constant. Experiments revealed a low water contact angle on our vaterite-coated paper, suggesting high ink jet print quality. Furthermore, although our test calcite-coated and silica-coated samples exhibited bleeding, our vaterite-coated samples matched commercial silica-coated samples in quality, probably, because the large hydrophilicity of vaterite promoted quick inward absorption of inks before they could spread laterally on the surface.

Moving object segmentation plays an important role in a complex object tracking system. This system decides whether the current block belongs to the object region or not. In this article, a scheme using background modeling based on runtime-weighted features for robustly adaptive moving object segmentation in infrared (IR) image sequence is proposed. Proposed background modeling for an open hardware (H/W) architecture design decreases the size of the search area to construct a sparse block template of search area in infrared images. The authors also compensate for motion compensation when the image moves in previous and current frames of IR imaging system. The method of separation of background and objects applies to adaptive values through time analysis of pixel intensity. The proposed method uses more feature information such as intensity, deviation, block matching error, and velocity. The weighting values give a higher weight to feature information which has a large difference between the object and the background region. Based on experimental results, the proposed method showed real-time moving object segmentation through background modeling in the proposed embedded system.

In detection and tracking of a small or large moving object in infrared (IR) imaging systems, it is necessary to perform analysis of the object in real time. The authors proposed the facet-based detection scheme for a small moving object with zero-mean Gaussian noise in previous research. However, it is difficult to detect larger moving objects using the facet-based model because the kernel size in the facet-based model is 5×5 pixels. In this article, the authors propose a robust detection scheme using the facet-based model in IR for larger moving objects. A new condition for the object is proposed for the robust facet-based detection of a larger object with zero-mean Gaussian noise. In the proposed algorithm, first, we extract a mean of image intensity from the center of the facet in the region of interest (ROI) of the first frame. Second, we apply the facet-based model to the same positioned pixel in a subsequent frame. The pixels are detected from the maximum extreme condition. The pixels are detected from the maximum extreme condition. The experimental results show that the proposed algorithm is efficient and robust.

The main purpose of using a camouflage pattern is to disrupt the basic shape of an object to hide or camouflage it in a specific environment. Department of Textiles at the Faculty of Natural Sciences and Engineering (University of Ljubljana, Slovenia) collaborated in the objective research project Knowledge for Safety and Peace 2006–2010 funded by the Slovenian Ministry of Defense. The basic goal of the research was to determine the procedure for designing a new camouflage pattern of the Slovenian urban environment and to visually analyze the chosen camouflage patterns in order to meet the visual properties, camouflage, and optical requirements. The experimental part included a selection of representative parts of the urban environment, classification of digital images, composition of a camouflage pattern, industrial pattern printing on textile, and finally, image and visual analysis of a digital pattern. The final camouflage pattern corresponded to all technical, formative, visual, and military requirements.

The body image visible on the Turin Shroud (TS) has not yet been explained by science; this article proposes a hypothesis of image formation based on corona discharge (CD). Even if the environmental hypotheses relative to CD can be refined, many facts detected on the TS body image seem in agreement with the characteristics of an energy connected to CD and related to the human body enveloped in it. After a synthesis of the proposed imaging mechanisms and a presentation of the main characteristics of CD, the results, both at macroscopic and microscopic levels, of some experiments are presented and discussed also in light of some comments coming from scholars of Shroud Science Group. The results support the hypothesized mechanism of image formation and they show no appreciable chemical-physical differences from the image features of the TS. Therefore they confirm that the proposed CD mechanism could have been involved in the TS body image formation.