Phosphate fiber patents

Table 8.1. The Patent Estate of Phosphate Fiber Patents had been granted or were pending in each of the following nations Argentina, Australia, Austria, Belgium, Brazil, Canada, France, Great Britain, West Germany, Holland, Italy, Japan, Luxembourg, Mexico, Sweden, Spain, Switzerland, and United States...

Almost every week several callers the world over inquire as to sources of phosphate fibers. They ask, Are you manufacturing this product Is anyone, anywhere, manufacturing this product Regretfully, I must tell them that I know of no commercial source of the fibers. Response to this product has been very rewarding to me, as an inventor. Monsanto s management made a decision not to manufacture the product and to allow their patent estate to lapse, rather than pay annual fees required to keep the estate active. The problems with potential lawsuits are ever present. 

A list of patents that were active or were pending when the Phosphate Fibers Project was dropped is shown in Table 8.1. The two original composition of matter patents that were granted to me, before yearly fees were required to maintain patents rights in the United States, are still active, as relics of the past. A much publicized reason given for abandoning the new phosphate fiber product was a potential for... 

The future of phosphate fibers should be very bright when the patents on the composition expire in 1999. In the author s mind there has never been a safety issue with phosphate fibers or any other inorganic phosphate that does not contain a toxic cationic or anionic function. Phosphates such as sodium, potassium, calcium, magnesium, ammonium, and hydrogen have never caused a problem of any type with perhaps the exception of renal stones. In this case it may be more of a condition than the cause of a condition. Urine is known to be saturated with respect to calcium phosphates. Some threshold agent or other mechanism that is poorly understood keeps kidneys from becoming completely calcified even in the healthiest of persons. 

Several patents were applied for dealing with phosphate fibers and bone implants " while others dealt with frictional materials for brakes, clutches, and sheets.There was very little that was novel in these patents when compared to... 

Hughes Aircraft [243] patented a graphite fiber reinforced sihca matrix composite, comprising of carbon fibers bonded together in a matrix of sihca, boron phosphate and p-spodumene modified with a minor amount of an alkahne earth metal oxide. The extremely low (nearly zero) coefficient of thermal expansion coupled with the moderate thermal conductivity and low density of the composite make the composite particularly suitable as a substrate material for high energy laser mirrors. 

A film of. colloidal silica on the surface of fibers, as in carpets, greatly reduces the pickup of dirt and leaves a cleaner appearance after vacuuming. It has been postulated that the silica forms a smooth adherent film to which soil particles do not cling, especially because it fills crevices in the fiber surface that would otherwise be filled with dark particles of dirt. Similar effects are reported on painted surfaces, plastic fabrics, window shades, and wallpaper (575). This type of use for colloidal silica was patented by Cogovan and Frederic (576). The advantage of using two hydrous colloidal metal oxides together is claimed by Florio and Rainard (577). Soluble aluminum phosphate is claimed to improve the adhesion of the silica to the fiber (578). 

In an attempt to remove the problems associated with the acetone coagulation bath, fibers were air-gap spun into aqueous salt solutions, eg up to 25% of diammonium hydrogen phosphate or potassium phosphate or 5% zinc sulphate (109). This patent also makes it clear that the corrosive nature of the solution is an issue in spinneret design. 

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