Patents narrowing

Once this process has been completed for each of the essential elements, patent claims maybe drafted which cover the invention. These claims will cover, in the broadest sense, only those elements of the invention which are essential. Narrower, more focused claims, however, should also be included within the patent appHcation. These claims may focus on aspects of the invention that the appHcant beHeves are preferred, or may otherwise represent essential aspects of any commercial product that will stem from the invention. Finally, claims should also be drafted to cover alternative forms of the invention. Such alternative forms of the invention may not necessarily be considered to be preferred commercially, but they may present an area where a competitor could attempt to engineer "around" the invention. 

If, upon review of the patent, the patentee discovers that the claims contain a formal error, are too narrow, or are too broad in view of the prior art, the patentee may ask the U.S. PTO to correct this error. There are four administrative vehicles for correcting errors in issued patents. The appHcation of each of these mechanisms is dependent on the nature and severity of the error, as weU as the source of its creation. 

A number of papers and patents describe polymerization processes to poly(tetramethylene ether) glycols having a narrow molecular weight distribution = 1.2—1.4). In principle, this can be achieved by having all chains grow quickly at one time, either by high temperature initiation (33)... 

Polystyrene produced by free-radical polymerisation techniques is part syndio-tactic and part atactic in structure and therefore amorphous. In 1955 Natta and his co-workers reported the preparation of substantially isotactic polystyrene using aluminium alkyl-titanium halide catalyst complexes. Similar systems were also patented by Ziegler at about the same time. The use of n-butyl-lithium as a catalyst has been described. Whereas at room temperature atactic polymers are produced, polymerisation at -30°C leads to isotactic polymer, with a narrow molecular weight distribution. 

The controlled synthesis of polymers, as opposed to their undesired formation, is an area that has not received much academic interest. Most interest to date has been commercial, and focused on a narrow area the use ofchloroaluminate(III) ionic liquids for cationic polymerization reactions. The lack of publications in the area, together with the lack of detailed and useful synthetic information in the patent literature, places hurdles in front of those with limited loiowledge of ionic liquid technology who wish to employ it for polymerization studies. The expanding interest in ionic liquids as solvents for synthesis, most notably for the synthesis of discrete organic molecules, should stimulate interest in their use for polymer science. 

Recently, patented ethoxylation catalysts have become available that can significantly narrow the ethylene oxide distribution of the alcohol ethoxylates used to obtain alcohol ether sulfates. These products are termed peaked alcohol ether sulfates whereas all others are termed conventional alcohol ether sulfates. Peaked alcohol ether sulfate solutions thicken more than those with a conventional ethylene oxide distribution [78]. Peaked alcohol ether sulfate solutions also exhibit behaviors different from those of conventional sulfates [79]. Smith [78] studied the viscosities of 15% sodium dodecyl ether sulfate solutions of both families with NaCl content between 2% and 10% at 25°C using a Brookfield model DVII viscometer at a shear rate of 2 s 1. The results are shown in Fig. 5 where the very different viscosities achieved are clearly observed. 

Figure 17.3 Airway obstruction, (a) Normal, patent airway with radial traction offered to it by surrounding airways. Resistance in this airway is low and air flows through it freely, (b) The airway is obstructed by the presence of excess mucus and airway resistance is increased. Airflow is reduced, (c) Thickening of the airway wall due to inflammation or edema narrows the lumen of the airway. The decrease in airway radius increases airway resistance and decreases airflow, (d) Destruction of surrounding airways results in the loss of interdependence, or radial traction. Without the structural support offered by surrounding airways, the central airway collapses and airflow through it is reduced.

Suggested Best Practices for Chemists 1. Claims in a patent application tend to begin broadly and then narrow down to important individual compounds. Scrutinize application claims to make sure the most important compounds (e.g., clinical candidates and backups) are individually claimed. One important compound = one claim. 

Chapter 31 provided that anyone could request the Patent Office at any time to reexamine an issued patent by citing new references. Written arguments could be submitted, the patentee could narrow his claims, and the Patent Office would reexamine the patent in the light of this new information. If, during litigation, the validity of a patent were attacked because of new references that weren t before the Patent Office, Chapter 31 required that this too go to the Patent Office for reexamination and for an advisory opinion by the examiner. This is based on the statistic that somewhat over 70% of the patents that the courts have held invalid over the past few years were held invalid on the basis of references that were not before the Patent Office, and presumably if the Patent Office had had the references, they would not have issued the patent. Reexamination under Chapter 31 would be limited to published references, and thus there would be no need for discovery or depositions or cross-examination. It would be an inexpensive procedure that would cover almost all of the reasons for invalidity that could arise in a fullblown opposition proceeding. 

The quality of the support is especially critical if the formation of the top layer is mainly determined by capillary action on the support (see Section 2.3.2). Then, besides a narrow pore size distribution the wettability of the support system plays a role (see Equation 2.1). An example of the synthesis of a two-layer support and ultrafUtration membrane is given in the French Patent 2,463,636 (Auriol and Trittcn 1973). In many cases an intermediate layer, whose pore sizes and thickness lie between those of the main support and the top layer (see Figure 2.2), is used. This intermediate layer can be used to improve the quality of the support system. If large capillary pressures are used to form such an intermediate layer, defects (pinholes) in the support will be transferred to this layer. This can be avoided by decreasing the acting capillary pressures or even by eliminating them. This can be done in several ways. 

The preparation of a ferrofluid emulsions is quite similar to that described for double emulsions. The starting material is a ferrofluid oil made of small iron oxide grains (Fe203) of typical size equal to 10 nm, dispersed in oil in the presence of an oil-soluble surfactant. The preparation of ferrofluid oils was initially described in a US patent [169]. Once fabricated, the ferrofluid oil is emulsifled in a water phase containing a hydrophilic surfactant. The viscosity ratio between the dispersed and continuous phases is adjusted to lie in the range in which monodisperse fragmentation occurs (0.01-2). The emulsification leads to direct emulsions with a typical diameter around 200 nm and a very narrow size distribution, as can be observed in Fig. 1.33. 

Also, during examination of a patent application the scope or breadth of the claims often needs to be narrowed because of prior disclosures. Any amendments to the claims must be based on the contents of the application and so, ideally, the patent application contains many layers of fall-back positions which identify useful features or preferred variants of the invention ranging from the full scope of the claimed invention which was initially considered to be justified, down to the specific embodiments described. 

The bulk polymerization of styrene to give a narrow molecular weight distribution has appeared in a U.S. patent [45]. The polydispersity reported was... 

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