Abstract— Recent advances in both organic‐ and inorganic‐based electronics processed on flexible substrates offer substantial rewards in terms of being able to develop displays that are thinner, lighter, robust, and conformable, and can be rolled away when not required. In addition, plastic‐based substrates coupled with the recent developments in solution deposition and ink‐jet printing for laying down OLED materials and active‐matrix thin‐film‐transistor (TFT) arrays open up the possibility of cost‐effective processing in high volumes using roll to roll (R2R) processing. To replace glass, however, a plastic substrate needs to be able to offer some or all of the properties of glass, i.e., clarity, dimensional stability, thermal stability, barrier, solvent resistance, and low coefficient of thermal expansion (CTE) coupled with a smooth surface. In addition, a conductive layer may be required. No plastic film offers all these properties so any plastic‐based substrate will almost certainly be a multilayer composite structure. This paper will discuss the issues associated with selecting plastic materials, contrast the various options, and highlight how to gain optimum performance through process control. This will be illustrated with examples of film in use in flexible electronic applications.

Flexible displays and flexible electronics is an area generating considerable interest at present. This article will discuss the requirements of a base substrate for flexible displays and contrast the plastic films that are being developed for this application. The review will cover how the surfaces and properties of the films are being engineered to make them suitable for laying down barrier coatings and for laying down thin film transistor arrays. The barrier technologies that are being developed and the issues facing the development of a ''flexible glass'' will be discussed.

SUMMARY Repetitive genomic regions include tandem sequence repeats and interspersed repeats, such as endogenous retroviruses and LINE-1 elements. Repressive heterochromatin domains silence expression of these sequences through mechanisms that remain poorly understood. Here, we present evidence that the retinoblastoma protein (pRB) utilizes a cell-cycle-independent interaction with E2F1 to recruit enhancer of zeste homolog 2 (EZH2) to diverse repeat sequences. These include simple repeats, satellites, LINEs, and endogenous retroviruses as well as transposon fragments. We generated a mutant mouse strain carrying an F832A mutation in Rb1 that is defective for recruitment to repetitive sequences. Loss of pRB-EZH2 complexes from repeats disperses H3K27me3 from these genomic locations and permits repeat expression. Consistent with maintenance of H3K27me3 at the Hox clusters, these mice are developmentally normal. However, susceptibility to lymphoma suggests that pRB-EZH2 recruitment to repetitive elements may be cancer relevant.

Poly(ethylene terephthalate) (PET) has wide acceptance for use in direct contact with food, can be recycled and can be depolymerized to its monomer constituents. Advances are continually being made to reduce the environmental ‘footprint’ that the polymer leaves. This paper discusses new advances in three specific areas, ie process developments, catalysis and polymer degradation, that address this issue. © 2002 Society of Chemical Industry