Recent Patents on Materials Science - Volume 4, Issue 3, 2011

This article summarizes the state of the art as documented in recent patent applications concerning the production of stitch-bonded multi-plies for usage in fiber-reinforced composites. Stitch-bonded materials have proven to hold great potential and are currently in use for a number of large-scale applications especially in the wind energy industry. Accordingly, technological progress is being documented in the patent literature on all stages of the production process of such fabrics, i. e. the design of the stitch-bonding machines, the production process and the textile fabrics themselves. Applicants for such patents are likewise to be found along the production chain. Most active in patenting their inventions are machine manufacturers, producers of textile preforms, end-users, and research institutions. While some of these inventions relate to minor process improvements or have found no industrial application so far, some of the granted patents were widely discussed, since they have widespread implications on the work of all competitors of the respective patentee.

Thermally sprayed coatings are very effective tools for high-temperature applications in energy and aerospace industries. They are applied on the surface of complex components as those of turbine engines in order to provide enhanced thermal and environmental protection against heat transfer, high-temperature oxidation, hot-corrosion, wear and erosion. Thereby, they are suitable to significantly increase the capability and the durability of these components as well as the efficiency of turbine engines, in accordance with the growing demand for higher performance and lower environmental impact. The recent developments about anti-oxidant coatings, thermal barrier coatings (TBCs), environmental barrier coatings (EBCs), abradable coatings and wear resistant coatings are summarized in this paper. The patents related to these applications are reviewed.

Silicon carbide (SiC) is an attractive material for high-temperature, high-power, high-frequency applications, due to its outstanding electrical, mechanical properties, and chemical inertness. SiC semiconductor technology has been developed widely since the commercialization of 6H-SiC and 4H-SiC bulk SiC wafers in 1990s. This paper reviews the recent patents on SiC semiconductor technology, introduces the achievements both in academy and industry for micromachining technologies, circuits devices. All these developments are driving high-performance SiC devices into harsh environment applications.

Incising is preferred prior to preservative treatment of refractory or difficult-to-treat species. Incising of wood reduces check development, facilitates drying of refractory species, and improves the penetration and retention of preservatives. Thus, it reduces the susceptibility of wood to biological degrading agents, extends the service life, and ensures structural soundness of wood. In spite of these benefits, high density needle/ knife incising significantly reduces wood strength properties. But recently developed laser (CO2 laser) incising of wood has limited impact on the strength reduction of wood. Laser incising also ensures deeper penetration of preservatives than needle/knife incising as cell lumens are free from clogging by dust. Bioincising also offers a good potential for improving the permeability of preservative in wood by making holes in cell wall. Extensive research is recommended on laser incising and bioincising of wood to improve the technical suitability for preservatve treatment. In this paper method of incising, incising density and both the beneficial and detrimental effects of needle/ knife incising, laser incising and bioincising for preservative treatment of wood based on related patents are reviewed.

From the past few decades, tremendous awareness has been laid on the use of natural polymers in drug delivery systems. Chitosan (CS) biomaterials are one of the most versatile used polymers in drug delivery systems due to their unique qualities. CS, obtained by deacetylation of chitin, is a natural, hydrophilic, nontoxic, biocompatible, bioadhesive and biodegradable polysaccharide suitable for applications in pharmaceutical technology. Its role in drug delivery systems was examined by considering the changes in the chemical and biological properties of the polymer. CS can be engineered into different shapes and geometries such as nanoparticles, microspheres, membranes, sponges and rods and has been used for the delivery of drugs through various routes including oral, ocular, intranasal etc. CS has also been found to be used as a support material for gene delivery, cell culture, and tissue engineering. Chemical modification of CS is useful for the association of bioactive molecules to polymer and controlling the drug release profile. This paper reviews the methods of preparation of CS derivatives intended for controlled drug delivery, their properties, degradation mechanisms and most important their biomedical applications in drug delivery. A number of recent patents regarding the role of CS in ocular, gastrointestinal (GI), brain and colon targeting etc have also been disclosed.

The sol-gel technique through the formation of colloidal suspension (sol) and gelation of the sol into the gel enables the incorporation of active substances into the material during the processing. For biotechnology applications, biomolecules (such as proteins, enzymes, antibodies etc.) or bioactive substances (for example drugs) incorporation into the sol-gel matrix has been extensively studied and constituted a challenge for many researchers. This review highlights some discoveries reflected in a series of patents, in the field of sol-gel synthesis applied in biomedicine. These are considered the sol-gel processed carriers for the controlled release of bioactive substances, bioactive coating of biomedical implants by sol-gel technique and encapsulation of biomaterials in matrices prepared via sol-gel process.

The patents annotated in this section have been selected from various patent databases. These recent patents are relevant to the articles published in this journal issue, categorized by materials, biomaterials, biological materials, magnetic materials, medical implant materials, nanomaterials, ceramics, plastics, polymers, semi-conductors, coatings, composites, paper, wood, textile, methods, design and techniques.....